Saturday, September 28, 2019

Iris Publishers-|Iris Publishers-Open access Journal of Civil & Structural Engineering | Italians’ Public Opinion on the Road Roundabouts SafetyErodibility Potential of a Sand Dredging Site in Rivers State, Nigeria



Authored by Nwankwoala HO


This study aims at determining sand erodibility potential using sand properties of the wetland, comprising different soil groups or types. Mathematical formation, tables and charts were used for the evaluation. Investigated soil properties included Sand Organic Matter (SOM), granulometry of sand, soil structure and permeability. The determined erodibility factors, hence soil erodibility potentials were significantly high. Percentage of soil organic matter was significantly low. Percentage of sand was generally high (99.33 on sieve number 4) and (95.44 on sieve number 8) using the MIT/British standard classification. However, the study provided baseline information on wetland erodibility for the reduction of soil susceptibility to erosion when considering any appropriate wetland development projects. To dredge sand and other materials for use in construction industry, principally for use in concrete, it is recommended that dredging activity may be carried out on the site.
Keywords: Erodibility; Soil susceptibility; Permeability; Wetland; Dredging; Soil properties

Introduction

Dredging operations entail the removal of bed materials and associated vegetation from a river channel. It is an underwater excavation to re-establish a channel so as to improve navigation or for commercial activities [1]. The dredged materials may be deposited in uniform layers over wet land vegetation or open bay bottom [2]. In Nigeria, manual dredging by natives has been in operation since the early part of the 19th century. This according to Aroh [3] was to get sharp sand (for construction purposes) and prevent sinking of boats. Sand erosion is a gradual change that is difficult to determine from environmental agents e.g. rainfall, runoff, streams and wind solely but coupled with dredging activity, sand erosion is determinable. Sand erosion is generally a three-step process of sand particles detachment, particles transportation or particles displacement and finally deposition at a different or new location [4]. Sand itself is a material with lesser degree of cohesion and therefore is vulnerable. The susceptibility of sand surface to the vagaries of erosion defines sand erodibility.
Sand physical properties, namely particle size distribution (soil texture), structure, organic matter content and permeability govern erodibility [5]. Texture is the mix proportion of sand, silt and clay. Erodibility is high for sandy soil. Sandy soils with small amounts of fine, medium or coarse particles (2.00mm and 0.02mm) are found to have high erodibility. Sand structure is the aggregation of identifiable shape and bad aggregation which enables the sand to be eroded by the detachment force of a dredger. Also, sand organic matter (SOM) being highly discouraged due to heat in sand does not bind sand particles together into sticker aggregates, thereby offering no resistance to erosion. Permeability is the measure of the rate at which water percolates through sand under a head of water and is a function of sand structure, texture and bulk density, hence a function of sand particles [4]. Because of the high percolation feature of a sandy soil, erodibility is high hence erodibility can be defined by soil partcles size distribution. Particles size distribution is very important in soil conservation, engineering and management of such inherent properties of the sand can influence its erodibility. This study therefore is aimed at evaluating and determining sand properties as well as erodibility potentials for dredging in the area.

The Study Location

The brackish water habitat chosen for the study is the River between Aka Village in Rumuolumeni and the Eagle Island all in Obio-Akpo Local Government Area of Rivers State (Niger Delta) in Nigeria. It is about 1 km to the confluence of the Bonny and Rumuolumeni Rivers. This area is under severe dredging for land reclamation by Master Energy Oil and Gas Company Limited hence removing a lot of Mangrove forest [6]. The Rumuolumeni River, a tributary of Bonny River is a brackish water habitat bothering the upper reaches of the Bonny and New Calabar Rivers which interferes with municipal development. The Bonny River has a maximum width of 2km and maximum depth of 15 meters and has the largest tidal volume compared to other Niger Delta Rivers [7]. This zone is a semi hot equatorial climate with a mean annual rainfall of 2405 mm [8]. The transition zone of the Niger Delta according to Fubara [9] coincides with the mangrove brackish water zone with its numerous inter-tidal flats and mangrove vegetation [10] to which the study location belongs. Towns around this Bonny River and transition zone are Bakana, Buguma and Abonnema all in Rivers State of Nigeria. Port Harcourt features a tropical monsoon climate with lengthy and heavy rainy season and very short dry season in the year [8]. It is only the months of December and January that truly qualify as dry season months in Port Harcourt metropolis. The Land area covers 924,000km2; ground level ranges from 7.2 to 16.9m above Mean Sea Level, MSL [11] (Figure 1).


Methods of Study

The study involved site visits and collection of sand samples at failure zones. Samples were taken and examined by three (3) borings and for each boring, 0.5m depth and 5m length apart, using the hand auger from all sand horizons distinquished in the profile pits. The samples were properly labeled in plastic bags to avoid natural moisture content lost. The samples were examined, identified and roughly classified in the field and later taken to the laboratory for tests. Laboratory analyses of sand samples included: Grain size analysis, density/unit weight, specific gravity, organic matter content and direct shear strength tests. These series of tests and classification were carried out on the samples in strict compliance with relevant geotechnical engineering standards including British standards (BS 1377) and [12-17]. Simple analytical methods were used to analyze and determine sand erodibility using the sand properties.

Results and Discussion

The moisture content of the soil is the physical state of the soil with respect to moisture content present at a particular time [18,19]. The moisture content of the three samples of the soil was low, due to their low water holding capacity. The bulk density of the sandy soil is high compared to clayey and silty soil. The structure of the soil is sandy and could promote a network of cracks and large pores that could accommodate infiltration that result in increased erosion due to decreased runoff. From the observed high values of sand percentage, sand as a non-binder to the coarse particles accommodated high infiltration of water and it does not resist erodibility. The organic matter content of the sand is comparatively low due to heat and the particles are not bonded, hence are further precursors to erodibility. The shear resistance of a soil arises from friction and inter-locking of particles. Interlocking of the soil grains give rise to the expansion or contraction in volume of the particulate material that make up the entire soil mass as they are subjected to shear strains. Expansion of soil volume is accompanied by a decrease of soil density, which resulted to a decrease in strength of the soil. Sieve analysis test results for samples are shown in Figures 2, 3 and 4, respectively (Tables 1-7) (Figure 2-4).


Conclusion

The erodibility potential of a sand dredging site is comparatively high. The erodibility factor (erosion susceptibility of the site comprising many different sand series using granulometry and other inherent properties, inherent sand particles (percentage of sand), soil organic matter content as well as profile permeability class and soil structure were determined and evaluated. The identification of the erodibility classes of these inland wetlands with respect to their component soils series would benefit our knowledge of the inherent soil properties which have key roles in the prospect and ability of water erosion of their soils where the soil series are mono-dominant or mixed; also, the identified erodibility gave baseline data of the catchment wetlands thereby exposing such soils (with their vulnerable soil series) to be managed under suitable project developments that will reduce the level of soil erodibility and the prospects of wetland soil erosion. This study is also of benefit to collection of baseline data on soil erodibility of sand and providing information on erodibility to assist in reducing soil susceptibility to erosion under appropriate project development in the wetland. It is recommended that, for navigation on the waterways and to dredge sand/other materials for use in the construction industry, principally for use in concrete, dredging activity may be carried out on the site.

Acknowledgment

None.

Conflict of Interest

No conflict of interest.

To read more about this article....Open access Journal of Civil & Structural Engineering

Please follow the URL to access more information about this article
https://irispublishers.com/ctcse/fulltext/erodibility-potential-of-a-sand-dredging-site-in-rivers-state-nigeria.ID.000522.php

To know more about our Journals....Iris Publishers

To know about Open Access Publishers

Iris Publishers-Open access Journal of Civil & Structural Engineering | Italians’ Public Opinion on the Road Roundabouts Safety



Authored by Natalia Distefano


Abstract

Roundabouts have been shown to provide significant safety and operational benefits, but a better understanding of public perceptions of roundabouts is critical in order to assess the contribution of the driving behavior of the users on their safety. Therefore, research on user behavior and preferences is a helpful tool in improving road safety and accident prevention. The aim of this study was to increase knowledge about user perception of risk in roundabouts. Risk perception in specific situations, factors influencing perceived risk, and attitude towards suggested safety improvements were studied as well as knowledge about traffic rules regulating the interaction between road users was studied. The instrument used is a web nationwide survey, which resulted in a total of 1728 responses throughout Italy. These results provide a macroscopic view of road user perceptions of roundabouts at a statewide level. This study also showed that web-based surveys provide an efficient means of collecting detailed public opinion data. The overall opinion that the respondents expressed against roundabouts is positive. However, the survey results have shown that the judgment suffers significant variability in relation to some specific components of the people. It is different the degree of safety of roundabouts towards the different types of users (for example, are considered less safe against cyclists). There are no substantial differences between the judgment of male drivers and that of females.

Introduction

Risk perception being a very common psychological phenomenon can affect road safety attitude directly as well indirectly. From a theoretical perspective, risk perception is considered a crucial factor in understanding the process of behavioural change. It refers to the subjective interpretation involved in different traffic situations [1]. Brown & Groeger [2] suggested that this perception is determined by information regarding the potential hazards in the traffic environment and information on the ability of the actor to prevent those potential hazards from being transformed into actual accidents. Perception of risk of road accidents by drivers can make them to adopt the behavior that helps in preventing road accidents. Risk perception affects drivers’ attitude regarding traffic rules, non-driving activities and driving responsibility [3]. Risk perception can modify human behavior. Risk perception affects drivers’ attitude regarding traffic rules, non-driving activities and driving responsibility.
Persons who possess high level of risk perception are more likely to be cautious and careful in their behavior. Risk perception helps in adoption of protective behavior. Risk perception is determined by the information of the potential hazards in traffic environment, and on the ability of driver to perceive the potential hazards resulting into actual accidents. There is a significant relationship between risk perception and road accidents [4]. Risk perception significantly indirectly affects the risky driving behavior [5]. Risk perception depends upon driving training, driving experience, age of drivers, etc. Driving training increases risk perception of drivers [6]. The age of driver influences risk perception and risktaking behavior [7]. Ulleberg & Rundmo [8] have shown that risk perception is significantly related to risky driving behavior and risk-taking attitudes. There is a positive correlation between risktaking attitude and risky driving behavior [9]. Risk taking attitude predicts risky driving behavior. Risk taking attitude comprises rule violations, speeding, careless driving, and drinking and driving. A study explains that risk perception and perception of driving tasks significantly affect drivers’ road safety attitude which comprises attitude regarding traffic rules, driving responsibility, non-driving activities, carelessness and aggressive behavior [3]. Higher drivers’ perception of risk and driving tasks more will be the improvement in their road safety attitude.
The aim of this study is to understand how the road roundabouts are perceived by people from the point of view of safety. It is known as the roundabouts represent the type of intersection that, from the point of view of the level of safety offered and the guaranteed operational performance, enjoys the highest consensus by the technicians of the sector. The goal is to understand whether the “technical agreement” corresponds to a similar level of support from the public. Numerous studies conducted internationally have allowed to quantify within a range between 10% and 40% decrease in the accident rate due to the construction of roundabouts in place of other types of intersections. The most obvious effects will have in cases where the takeover roundabouts at stop-controlled intersections. Smaller, but significant, are the benefits of the road roundabout in the redevelopment of signalized intersections. Distefano et al. [10] have quantified the extent of the relationship between the safety perception of the typical roundabout maneuvers and the following aspects: a) maneuver type, b) geometric characteristics of the roundabouts design elements. Brilon & Stuwe [11] have documented that the average diameter roundabouts (up to 40 m) are safer intersections signal regulated, while those of larger dimensions, while presenting accident rates often higher than those of signalized intersections, however, are zones of accidents less serious. Persaud et al. [12] have also shown as the accidents of greater severity (fatal or serious injury), are reduced, in the case of roundabouts, according very high percentage (70% - 90%).

Data Collection

In order to assess public perception of roundabouts for Italian people, the tool used was a web-survey. The questionnaire was designed by the authors of this paper and includes both general questions (age, gender, education, means of transport used most frequently), which targeted questions to capture information on the opinion of the interviewee on the safety level that he personally perceives roundabout. The first set of questions will be used to characterize the user in relation to the answers relating to the perception. The survey was conducted via web through the DISS website (Road Safety Centre). A total of 1728 survey responses were received during the implementation period from May to July of 2016. Details of the characteristic of survey respondents are presented in Table 1.
Table 2 shows the answers of respondents to questions designed to understand the level of knowledge of the rules of behavior in the roundabout. Most drivers believe that a roundabout need to be travelled while maintaining a constant speed (in entry maneuver, in circle on the circulatory roadway and in exit maneuver). It is true that it has the knowledge that in entry maneuver should decrease the speed, but it is not, however, aware that it is necessary to increase the speed on circulatory roadway and also at the exit in order to quickly dispose of the vehicle flow. Almost 20% of respondents believe that on circulatory roadway should take place at a lower speed than the entry maneuver (Table 2).



Analytical Method

In order to obtain a better understanding of road user perceptions of roundabouts, as well as to identify factors affecting these perceptions, a multivariate analysis is necessary. Particularly, discrete choice models provide an appropriate framework for conducting such an analysis. Furthermore, each of the response categories can be represented by a natural ordering structure (e.g., very favorable, favorable, unfavorable, very unfavorable). Ordered probability models are a form of discrete outcome models that relate dependent variables on an ordered discrete scale to a series of predictor variables. Ordered probability models are derived by defining a latent variable z as a basis for modeling ordinal ranking data.
z = βX + ε
where X is a vector of variables determining the discrete ordering for observation n,ε is a vector of estimable parameters, and β is a random disturbance. For this study, XLSTAT was used to estimate separate ordered probit models in order to examine public perceptions of roundabout. The judgments on roundabouts are assessed on a four-point scale. Table 3 presents the parameters of the ordered probit model developed (Table 3).
Table 3: Ordered Probit Model (normalized coefficients).


Result and Discussion

Following tables present the results of the ordered probit models that were used to examine public perceptions of roundabout related to the gender (Table 4), the age (Table 5), the age for gender (Tables 6 and 7), the occupation (Table 8), the travel mode (Table 9), and regular roundabout user or not (Table 10). (Tables 4-10)

The results of statistical analysis on the responses to the web-surveys show that:
1. The positive judgment (very favorable + favorable) is almost equal between men and women; However, it should be noted that the percentage of people who said they were very favorable is higher among men (Table 4).
2. Young people between 18 and 25 years perceive the roundabouts less favorably than other age groups (Table 5).
3. The user’s category of users more favorable at roundabouts (very favorable) is constituted by men between 51 and 70 years (39.52%) (Table 6).
4. The category of users more unfavorable at roundabouts is represented by younger women (2.53%) and older ones (2.59%) (Table 7).
5. The social context, defined by the occupation, does not appear be a parameter that influences the public perception of the roundabouts (Table 8).
6. Among the categories of drivers, depending on the mode of transport, the motorcycle riders are the ones who, more than anyone, have a positive perception of the roundabouts (although it represents only 3.70% of respondents); the less favorable users are the cyclists (Table 9).
7. The users who travel at least on a roundabout for their daily movements, perceive the roundabouts in a similar way to infrequent users (Table 10).

Conclusion

The research literature has shown roundabouts to provide for improved safety and traffic operations in comparison to signalized and stop-controlled intersections. Even the engineers and traffic planners agree that the roundabouts, if well designed, are the best solution to optimize operational performance and the level of safety for users. Consistent with prior research, the results of this survey showed that public opinion is strongly in favor of the roundabouts with an average percentage of 90% (sum of all those who have expressed a judgment “very favorable” and those who said they were “favorable”). The statistical treatment of data by multivariate logistic analysis was done so on a representative sample of respondents from all regions of Italy. The results of this study thus provide the public perception of roundabouts as an expression of the entire Italian’s people. Therefore, these results provide a macroscopic view of road user perceptions of roundabouts at a statewide level. In this way, they have exceeded the limits associated with surveys carried out only in local areas. This study finally showed that web-based surveys provide an effective and efficient means of collecting detailed public opinion data.

Acknowledgment

We thank the DISS (Italian Center Road Safety) which allowed to publish the online survey. With support of the DISS has been possible to reach all University of Italy and many public and private administrations.

Conflict of Interest

No conflict of interest.



To read more about this article....Open access Journal of Civil & Structural Engineering

Please follow the URL to access more information about this article
https://irispublishers.com/ctcse/fulltext/italians-public-opinion-on-the-road-roundabouts-safety.ID.000521.php

To know more about our Journals....Iris Publishers

To know about Open Access Publishers

Friday, September 27, 2019

Iris Publishers-Open access journal of Clinical Case Studies | Isoprenoid Quinone Composition of the Genus Microbacterium and Related Strains






Authored by Moh’d Nizar Battikhi

Abstract

The aim of this study is to compare pattern of Isoprenoid quinine of unspecified bacterial isolates from dairy product to reference strains type species of the genus Microbacterium.
Method: Twenty-eight strains of coryneform and related bacteria were studied for isoprenoid quinine content. Extraction of 100 mg of freezedried cells by chloroform: methanol (2:1v/v), extract was then run onto analytical TLC plates coated with o.5 mm Merck Silica Gel HF245.
Results: Out of the twenty-eight reference and unspecified strains M. lacticum and M. flavum are quite distinct and that the predominant of MK-8 in BL77/18. BL77/19 and BL77/20 support that these strains are related to M. flavum.


Introduction

Coryneform bacteria classification in Bergy’s Manual of Bacteriology [1] accommodate different genera as Cellumonas, Arthrobacter, Corynebacterium and Microbacterium described as incertea sedis. Other motile plant pathogens were added to coryneform group [2,3]. Numerical phonetic studies improved classification of coryneform [4,5]. Other markers were used to improve taxonomic position of coryneform bacteria such as DNA base composition determination [4,6-10], wall analysis [11-15] and mycolic acid analysis [2,15,16]. The use of additional marker (isoprenoid quinone) was recommended by [16,17] to improve classification of coryneform and related taxa. The analysis of the isoprenoid quinone of coryneform bacteria has been a useful aid to establish the taxonomic relatedness of bacterial strains [2, 3,17-20]. These quinines can be divided into menaquinones and ubiquinones abbreviation of their data is given in (Figure1a). Substantial investigation amongst coryneform have been carried out on the distribution of quinines bearing isoprenoid side chain. Bacterial quinones of this type can be sub-divided into menaquinones (2 methyl-3-polyisoprenyl 1-1,44 naphthoquinones and ubiquinones (co-enzyme Q; 12,3-dimethoxy-5-methyl-1-6- polyprenyl-1-1,4 benzoquinone (Figure1b). The menaquinones (related to vitamin K) show structural variation at C-2 and ,more especially, at C-3.Variation at C-3 include the length and degree of un-saturation of the polyprenyl side-chain [22] and the presence of hydroxyl [21] and epoxide groups [22]. Similarly, ubiquinones show variation principally in the structure of polyprenyl sidechain [23]. Therefore, the structure of these compound might be of great value in classification of coryneform and related bacteria [23]. Other studies demonstrated that organisms can be clustered based on the isoprenoid side chain of the menaquinones [2,3,20,24,25]. From their analysis Minnikin et al [22] concluded that MK_8(H2) was the major menaquinones of the animal associate corynebacterium. Microbacterium flavum, with consistently shows affinities with the animal associated corynebacteria in numerical phonetic studies, also contains MK-8(H2). They also reported that Micro bacterium ammoniaphilum contained MK-9(H2). Isoprenoid quinines are membrane-bound compounds (lipid molecules) found in nearly all living organisms. It marked structural variation depending upon the microbial taxon [27-30]. Therefore, organisms can be clustered based on isoprenoid side chain of their menaquinones. and hence differentiation between various taxa could be improved [3,17,18,27].


Method

Twenty-eight strains of coryneform and related bacteria were collected for the study. These were obtained from public and private culture collections (Table 1). Each strain was given number for ease handling. Several strains representing different taxa defined in study [4,5] where numerical phonetic surveys of coryneform and related bacteria were included as references. The unidentified strains were received from the National Institute of Research in Dairying, Sheffield, Reading and food Research institute, Norwich. All strains were originally obtained in freeze dried cultures.


General Growth Media

Strains were routinely subculture at three weeks intervals onto nutrient agar (Difco) plates and stored at 4C. After 2-3 days incubation at 37 °C. For broth culture Nutrient broth Media (Oxoid) media was and culture were stored at lyophilized aliquots in glass vials for future used were they resuscitated by transfer small amount of nutrient onto nutrient agar plates and incubated for 7 days. Nutrient agar (Difco) and nutrient broth (Oxoid) were used for growing all isolates. All media were sterilized by autoclaving at 121 °C for 15min. Culture were incubated for 24-48 H at 37 °C. Cultures were harvested by centrifugation at 8,000 rpm for 20min, in an MSE high speed M-18 centrifuge, washed in distilled water and re-harvested Organism were lyophilized and stored anhydrously as a fine powder until required and freeze dried for future used. Isoprenoid quinone analysis done by extraction of 100mg potions freeze dried organisms by a method described by Collins et al. [17] that proved to be satisfactory for the analysis of lipids. At the preparation phase ,components with chromatograph with vitamin K were the only isoprenoid quinines which were detected. Ultraviolet spectroscopy of the eluted quinines showed absorption maxima at 242,248,260,270 and 326nm (Figure 2), feature which are in accordance with the published data for menaquinones [28] where 100mg of freeze dried cells were mixed with 20ml chloroform: methanol (2:1v/v) in a 50ml conical flask and the suspension stirred for16-18h in the dark (isoprenoid quinine are susceptible to strong light). Organisms were removed by filtration and the extracts were evaporated to dryness under reduced pressure and teem below 37 °C. Components were detected by observing chromatograms under short-wave (254nm) ultra-violet light. The dried extracts were prepared as described in above then were re-suspended in small volume of chloroform: ethanol (2:1 v/v) and spotted onto analytical TLC plates coated with 0.5mm Merck Silica Gel HF245 (prepared by coating plates with slurry contains 40g gel HF245 per 100ml distilled water and drying overnight at 65 °C).
Plates were developed in petroleum ether (BP 60-80): diethyl ether (85:15 v/v). In this solvent system, the menaquinones migrate further (Rf 0.7) than ubiquinones (Rf 0.4). Vitamin K (sigma) an Ubiquinone’s -50 (BDH) were included as standard. The isoprenoid quinines were also isolated by eluting with chloroform from preparative TLC plates (1 mm, Merck silica Gel HF245) using the same solvent system. The quinines were detected by brief irradiation with ultraviolet light (245nm) when they appeared as dark brown spots on a bright green fluorescent background. Eluted samples were evaporated to dryness by a method based on Collins et al [17] proved to be satisfactory for analysis of lipids at the preparation phase, components with chromatographed with vitamin K were the only isoprenoid quinines which were detected. Ultraviolet spectroscopy of the eluted quinones showed maxima at 242, 248, 269, 270 and 326nm (Figure 2) feature which are in accordance with the published data from menaquinones [28]. The isoprenoid quinine was separated by reverse phase partition chromatography using appropriate standards. Components were detected by observing chromatogram under ultraviolet light (254nm).
In describing the menaquinones of strains, the following nomenclature was adopted. The symbol MK denoting menaquinone is followed by a number (e.g. 8, 9 or 10) denoting the number of isoprene units attached as a side chain (Table 2). A wide range of manaquinones with varying numbers of isoprene units were characterized within the group of the menaquinones although only one type predominated of Corynebacterium, oortii (strain C617 and C618) was MK9, a result in agreement with other study [20]). Likewise, the major quinine of Microbacterium flavum (C90) was MK8, again in agreement with published data [17,29]. In this study the menaquinones of 28 reference strains of Micro bacterium, Corynebacterium and unknown isolates were examined. The five strains of M. lacticum (C88,C,89,C787,C788.C789) tested were all contain eleven and twelve isoprene units as the predominant side chain of their menaquinone in contrast M. flavum (C90) was shown to contain MK-8 as the predominant menaquinones which is in agreement with other study by [2]. These observations agree with conclusion that M. lacticum and M. flavum are quite distinct, likewise the major menaquinone (MK-7) of Brochothrix thermosphacta (Microbacterium thermosphactum) support the other evidence that this species is quite distinct from both M. lacticum and M. flavum. The presence of MK-11 and MK12 in Corynebacterium laevaniformans (C626) agrees with other study [20]. Strains JP2/1/6 and strain JP2/1/5 were both contain MK-11 and MK12, which is similar to M. lacticum that showed resemblances. M. liquefaciens (C770, C771), Corynebacterium mediolanum (C69) and Brevibacterium imperial (C25) all shown to contain MK-11 and MK-12 a feature consistent with earlier study [19]. The unnamed strains used in this study showed that the predominant of MK-8 in BL77/18. BL77/19 and BL77/20 support that these strains are related to M. flavum. The similar menaquinones profiles of strains JP2/1/1 and`JP2/1/21which contain MK-11 and MK-12 supports their taxonomic relatedness but suggest that they may not closely related to M.flavum. The predominant of MK-8 in strains.


Discussion

The analysis of isoprenoid quinines of coryneform bacteria has been a useful aid to establishing the taxonomic relatedness of strains [2,18-21,26] These quinines can be divided into menaquinones and ubiquinones. By far the majority of coryneform contains menaquinones although different groups produce menaquinones with different numbers of isoprene units and may also differ in their degree of saturation. These differences appear to be taxonomically significant [26]. Thus, organism regarded as closely related on other evidence (numerical taxonomic data, cell-wall composition,) often have similar menaquinones while unrelated organisms frequently contain different components.
In this study the menaquinones of 28 strains were examined. The five strains of M. lacticum (C88, C89, C787, C788, C789) used all contained eleven and twelve isoprene units as the predominant side chain of their menaquinones. In contrast M. flavum (C90) was shown to contain MK-8 as the predominant menaquinone which agrees with other study [26]. These observations agree with the conclusion that M. lacticum and M. flavum are quite distinct. Likewise, the major menaquinone (ML-7) of Brochothrix thermosphata (Microbacterium thermosphactum) supports the other evidence that this species is quite distinct from both M. lacticum and M. flavum. The presence of MK-11 and MK-12 in Corynebacterium lave K-11 and MK-12 which showed their relatedness to each other and similar to M. lacticum. The significant of manaquinone in taxonomy was reported by Collins et al [18].

They showed that, amongst other criteria, the curtobacteria can be divided into two groups based on their menaquinones. The significant of menaquinone marker in taxonomy was clearly appeared by showing relatedness of unknown isolates as BL77/18, BL77/19. BL77/20 to each other and to M. flavum since they showed MK-8. Likewise, the similar menaquinones profiles of strain JP2/1/1 and JP2/1/21 which contain MK-12 supports their similar taxonomic position but they are closely related to M. flavum. Likewise, our result in this study showed the presence of MK-9 in strains JP2/1/11, JP2/1/20, JP2/1/15 and JP2/1/3 which suggest resemblance of these strains.

Conclusion

This study showed the significant of isoprenoid quinine as marker of clustering different strains according to their menaquinone content which may lay base line for future taxonomy. However, other markers may be need for further support.

Acknowledgement

None.

Conflict of Interest

No conflict of interest.

To read more about this article....Open access journal of Clinical Case Studies

Please follow the URL to access more information about this article
https://irispublishers.com/accs/fulltext/isoprenoid-quinone-composition-of-the-genus-microbacterium-and-related-strains.ID.000518.php

To know more about our Journals....Iris Publishers
To know about Open Access Publishers

Iris Publishers- Open access Journal of Clinical & Medical Sciences | If Medical Science could provide a Solution to One Healthcare Issue which would you choose?

 

 

Authored by Jack Ray Gallagher

Editorial

Ischemic heart disease and stroke have remained leading causes of death globally since the turn of this century, accounting for 15.2 million deaths in 2016 [1]. Alzheimer’s disease and related dementias became the fifth leading cause of death in 2016 but were not in the top 10 in 2000, [1] and a study published this month in The Lancet notes that while cardiovascular disease is still the No. 1 cause of death worldwide, cancer has surpassed it in wealthier nations [2]. Would you pick a cure for one of these deadly diseases as the most pressing healthcare issue to solve, or would you give higher priority to development of a spectacular technological advancement such as artificial neural networks with the broad potential to resolve a number of fatal diseases? Before deciding on the healthcare issue most in need of an immediate solution, consider these lines from English poet Samuel Taylor’s “The Rime of the Ancient Mariner” [3]:

Water, water everywhere, / Nor any drop to drink. To be relevant to today’s healthcare issues, this line could be rephrased as: Data, data everywhere, / Nor any know to think.
Like the sailor stranded on a ship surrounded by saltwater that he cannot drink, we are surrounded by inconsistent or spotty realworld data that we cannot use to help find cures and solutions to our most serious diseases and healthcare issues. Our collective task is to determine how to “desalinate” our oceans of real-world data to generate the useful and actionable real-world evidence needed to help resolve critical healthcare issues. The relatively recent emergence of big data in healthcare is an organized attempt to accomplish this onerous task.

Big data analytics potentially offer great benefits to all spectrums of medical and clinical care including improved efficiency and effectiveness of medical treatments, accelerated drug discovery, and enhanced personalization of patient care [4]. Big data in healthcare are derived from such sources as electronic health records (EHRs), claims and other payor records, public records, research studies, government agencies, web and social media, specialized commercial databases (e.g., medical imaging, genomic sequencing), smart phones, and wearable devices. Big data are distinguished from traditional data used in healthcare decision making by their high levels of the “3 Vs”-velocity, volume, and variability-and are far too large to manage with traditional software and/or hardware [5]. Artificial intelligence, machine learning, and natural language processing are among tools that have evolved to help accommodate big-data demands. Compared with other industries, healthcare has been slow to adopt and leverage these and other new analytical technologies, possibly due in part to the special data challenges in healthcare including issues of privacy, security, and standardization [6].
I maintain that curing our big-data woes is as important as curing even the most prevalent deadly disease and could provide the tools to cure or ameliorate many diseases. I also believe scientific journals have a responsibility to highlight the shortcomings of existing big data and to share solutions. Current Trends in Clinical & Medical Sciences is committed to this task.

Acknowledgment

None.

Conflict of Interest

The author has no conflict of interest.
To read more about this article....Open access Journal of Clinical & Medical Sciences

Please follow the URL to access more information about this article
https://irispublishers.com/ctcms/fulltext/if-medical-science-could-provide-a-solution-to-one-healthcare-issue-which-would-you-choose.ID.000513.php

To know more about our Journals....Iris Publishers
To know about Open Access Publishers

Tuesday, September 24, 2019

Iris Publishers-Open access Journal of Cardiovascular Research | Cross-Cultural Confirmation of the Type D Personality Construct




Authored by Les Rodriguez



The Type D personality construct is characterized by negative affectivity and social inhibition and is a predictor of poor outcomes in cardiovascular health [1]. Patients with coronary artery disease and Type D personality have a higher rate of mortality and nonfatal myocardial infarction [2]. They also have a four to six times higher risk for anxiety and depression [3], five times higher risk for poor mental health [4] and four times higher risk of recurrent cardiac episodes [5] compared to individuals who are not Type D personality. They are at a significantly higher risk of myocardial infarction, a poorer prognosis following a myocardial infarction [6], and more cardiovascular-related health problems compared to individuals who are not Type D personality [7].
Type D personality is a known risk factor for premature, cardiac-related death [8]. The Type D personality construct has been linked to a number of cardiovascular conditions that strain, weaken and debilitate and ultimately damage the heart muscle as well as serious cardiac outcomes; heart arrhythmias [9], chronic heart failure [10], coronary artery disease [11], hypertension [12], myocardial infarction [4], and peripheral arterial disease [13].
The cross-cultural confirmation of the Type D personality construct is well documented in research literature. The Type D personality construct has been researched and generalized in a number of different cross cultural contexts and populations and its relationship with a number of health conditions examined; Dutch military personnel deployed to Afghanistan [14], Dutch military personnel awaiting deployment [15], domestic violence victims [16], patients with chronic heart failure and peripheral artery disease [17], healthy patients [5], Chinese patients with heart disease [18], Danish patients with heart disease [3], Scottish patients with heart disease [4], work-related problems [6], development of posttraumatic stress disorder [14], irritable bowel syndrome [19], development of stress cardiomyopathy [20], and poor medication adherence [21] among many others.
Some researchers argue that the Type D personality construct does not generalize across all cultures because studies have had limited coverage in countries in Africa, Asia and South America, therefore, generalization of the Type D personality construct to these countries cannot be made [10]. In contrast, Kupper, Pedersen, Hofer, Saner, Oldridge & Denollet (2013), concluded that their study’s ability to establish cross-cultural equivalence in a large sample size, a strength of their study through the HeartQoL project, was a promising outcome because it included many different cultures, countries and languages [10].

The study from the International HeartQoL project conducted a cross-cultural analysis of 6,222 patients with ischemic heart disease from 22 countries to examine the prevalence and validity of the Type D personality construct and demonstrated cross-cultural equivalence [10]. The study included countries from Western Europe (Netherlands, Belgium, Austria, Germany, Switzerland, and France), Southern Europe (Italy, Spain, and Portugal), Northern Europe (Denmark, Sweden, and Norway), Eastern Europe (Ukraine, Poland, Hungary, and Russia), as well as English speaking countries (Australia, Canada, Ireland, United Kingdom, United States [10]. The Type D personality construct has been the subject of research at a global level with studies conducted in many countries such as: Belgium, Iceland, Norway, Ukarine, Korea [22], Canada [23], China [24], Denmark [25], England [26], Germany [27], India [28], Israel [29], Hungary [30], Italy [31], Netherlands [12], Poland [32], Sweden [33], Turkey [34], and Greece [35].

The results of the study from the International HearQoL project of the Type D personality construct showed consistency between countries in Western Europe, Southern Europe, Eastern Europe, Northern Europe, and the United States thus demonstrating that the cross-cultural validity and reliability of the Type D personality construct.

Author contributions

The author confirms being the sole contributor of this work and approved it for publication.

Acknowledgement

None.

Conflict of Interest Statement

The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.




To read more about this article....Open access Journal of Cardiovascular Research

Please follow the URL to access more information about this article

https://irispublishers.com/ojcr/fulltext/cross-cultural-confirmation-of-the-type-d-personality-construct.ID.000526.php

To know more about our Journals....Iris Publishers

To know about Open Access Publishers

Iris Publishers-Open access Journal of Cardiovascular Research | The Role of 4DCT in the Evaluation of Patients with Bio-Prosthetic Valve Thrombosis





Authored by Parivash Badar

Valvular heart disease affects >100 million patients worldwide out of which 200,000 cases of aortic valve replacements are performed annually and the numbers are predicted to rise further due to the aging population and a subsequent increase in degenerative valve disease. Based on an analysis of the Society of Thoracic Surgeons National Database; between 1997 and 2006, Bioprosthetic tissue valve replacement gained prominence causing a massive shift from mechanical to bioprosthetic valve replacements. The use of mechanical valves decreased to 20.5%, whereas the use of bioprosthetic valves increased to 78.4% [1, 2] The transition from mechanical to bioprosthetic valve was partially attributed to the fact that, younger individuals refuse long-term anticoagulation and elderly patients are at a higher bleeding risk [1].

Historically, it was regarded that chronic anti-coagulation and monitoring could be deferred in patients receiving bioprosthetic tissue valves. However, recent data shows bioprosthetic tissue valves could also develop thrombosis, particularly since the utilization of 4D CT angiography (4DCT) in practice. Most cases of valve thrombosis were diagnosed at a median of 6 months post-procedure, with patients presenting with Heart-Failure like symptoms i.e.; progressive dyspnea with exertion, low left ventricular ejection fractions, orthopnea, paroxysmal nocturnal dyspnea, and patients demonstrating an increased requirement of diuretics [3-6] Figure 1. Other likely predictors of valve thrombosis include paroxysmal atrial fibrillation, sub-therapeutic INR in patient who were anticoagulated with vitamin K antagonists, increased body mass index and lack of anti-coagulation [1,7]. Valve thrombosis may be associated with smaller valves <23 mm or valve in valve procedures [3,4].

Echocardiographic findings of significant increase in transvalvular gradient [5] in addition to leaflet thickening and abnormal cusp mobility serves as independent predictors of valve thrombosis. 4DCT, with its superior spatial resolution, is superior to echocardiography in analyzing surgical aortic valve replacement (SAVR)/Trans-catheter Aortic Valve Replacement (TAVR) leaflets’ morphology and excursion [3-6,7,8,9] (Figure 2A&2B).

There has been a colossal change in the T2DM treatment options in the last decade with several new classes of drugs emerging including dipeptidyl peptidase-4 inhibitors, glucagon-like peptide 1 agonists and sodium glucose cotransporter-2 inhibitors (SGLT-2i). Further to United States Food & Drug Administration (US FDA) recommendations, all the new drugs now need to go through cardiovascular (CV) safety studies and prove non-inferiority. Surprisingly, SGLT-2i not only demonstrated CV safety but in fact were shown to reduce heart failure admissions and improve major adverse cardiac event (MACE) outcomes in patients with established cardiovascular disease. This mini-review is focussed on summarising the cardiovascular benefits of this exciting class of new drugs.

The latest generation CT scanners with their superior temporal and spatial resolution are now being increasingly utilized to further analyze valve replacements in an accurate manner. They are also able to identify degenerative disease of the bioprosthetic valve replacements by picking up leaflet calcification as well. 4DCT was thus is considered not only superior in terms of its imaging capabilities but it’s also considered a sensitive marker for early calcification suggestive of bioprosthesic stenosis in the making and hence has a lower threshold for identifying such cases [3,4,7,10- 13]. In our clinical practice we treat symptomatic patients with Warfarin when indicated and follow up and monitor them with echocardiography and 4DCT. Patients who receive prompt anticoagulation and monitoring are often resolved of further symptoms and see better outcomes.

Conclusion

4DCT with its advanced temporal and spatial imaging capability is an imaging modality that has helped shape clinical practice in patients with bioprosthetic valve thrombosis and is effective in clinical decision making for anti-coagulation therapy [3,4,7,10- 13]. An increased awareness of symptoms and echocardiographic parameters is necessary when managing such patients. We look forward to more studies in the future that will put light on this topic [14-18].


Acknowledgement

None.

Conflict of Interest

No conflict of interest.

To read more about this article....Open access Journal of Cardiovascular Research

Please follow the URL to access more information about this article

To know more about our Journals....Iris Publishers

To know about Open Access Publishers

Monday, September 23, 2019

Iris Publishers-Open access Journal of Animal Husbandry & Dairy Science | Eating Characteristics of Wieners Produced with Gari




Authored by Akwetey WY

Abstract

Texture and sensory profiles of wieners produced with either 0% or 3% gari, with 20%, 25% and 30% water respectively were studied. Using gari did not significantly (p>0.05) influence cooking yield, odour and flavour in wieners. Consumer acceptability of texture attributes of wieners were significantly higher (p<0.05) in gari-treated wieners compared to the control because instrumental analysis of texture showed significant reductions (p<0.05) in hardness, springiness, gumminess, chewiness and cohesiveness when higher levels of water were incorporated. Adhesiveness was not influenced significantly (p>0.05) by treatment. The cost of producing wieners reduced by 8%, 35% and 41% respectively at 3% gari with 20%, 25% and 30% levels of using water. It was concluded that wieners could be manufactured with 3% gari and 25% water in order to save 41% of production costs and obtain desirable eating characteristics.
Keywords:Wieners; Gari; Texture and sensory profile; Consumer acceptability
Food texture and sensory characteristics are very important aspects of consumer acceptability and several instrumental testing methods have been developed for texture profile analysis (TPA) of various foods [1,2]. These tests depend on measurements of resistance of a food sample to force deformation such as puncture, cutting, shear and tensile strength. According to [1] TPA’s have the advantage of simplicity and the textural parameters obtained can be correlated with food texture sensory analysis. In recent times the most commonly used instrumental method is probably the compression method of texture profile analysis of foods because [3] had earlier suggested that this method mimicked the conditions to which food was subjected throughout a mastication process. Hence the compression parameters obtained with TPA have been employed by many researchers in their evaluations of meat products, including beef burgers and sausages, as a reliable scientific tool for determining the quality of a finished product and also, to select the best functional ingredients in order to optimize available resource inputs in the meat industry [4-8]. For example an instrumental measure of hardness as a component of the texture profile, offers information about the peak force at the first bite of a food product during mastication. So that ingredients which may offer some reduction in hardness and overall consumer acceptability could be beneficial in the search for softer and more ‘tender-bite’ processed meats such as wieners. Sensory evaluation was defined as a scientific principle used to evoke, measure, analyze and interpret those reactions to characteristics of food materials as perceived through the senses of sight, smell, taste, touch and hearing [9]. Human subjects are used as “instruments of measure” in the assessment of the complex sensations that result from the interactions of various food attributes and human senses in order to evaluate food quality in programmes such as quality control and new product development. When data generated from such sensory testing panels are statistically analyzed, the results may serve as an assay for the evaluation of, for example, the extent of flavor and odor desirability, especially when a new ingredient is being introduced into product manufacture for the first time. The sensory evaluation normally may be done by either a small number of people or by several hundreds of people depending on the types of information required. According to [10] most sensory characteristics of food can be seen to be measured well, meaningfully and completely only by human subjects. In using humans as instruments of measure, it is important to control all testing procedures and conditions including lighting, temperature, serving size, odours, and labelling of food samples to assure that errors due to psychological factors could be eliminated to the barest minimum, if not completely. Information in the scientific literature concerning texture profile and sensory attributes of meat products using gari as an ingredient in their formulations is very scanty. Gari is a cassava product that is relatively less expensive compared to other carbohydrate sources that can be used in meat formulations. It has characteristics that can be useful to meat texture and sensory improvement. In [8] reported that using 10% hydrated gari in beef burgers reduced hardness significantly without any compromise on overall burger acceptability by consumers. The objective of this study was to evaluate the eating characteristics of wieners produced with gari as non-meat ingredient in partial replacement of beef. Specifically, the costs of production, instrumental texture profiling and consumer acceptability of wiener attributes were determined.
Raw materials and wiener production
Frozen beef trimmings and all spices were obtained from the Meat Laboratory of the Ohio State University. Gari was obtained from Ghana through the Berekum Market (Columbus, OH, USA), and used to replace beef (w/w) in four wiener treatments, comprising of control (0% gari with 20% water), and 3% gari formulated with 20%, 25% and 30% water respectively. The four treatments were respectively coded as 0T20, GT20, GT25 and GT30. The meat batter was produced using a Sydelmann chopper (Stuttgart, Germany) at a consistent temperature of 10.56°C, stuffed into cellulose casings and hand-linked at 6cm lengths. Wieners were cooked and smoked in an Enviro-Pack oven (Clackamas, OR, USA) to internal temperatures of 73.88°C after which they were chilled at 2°C overnight, vacuum packaged and stored at -18°C for further analysis.
Parameters measured
Cost of production and cooking yield: The costs of producing wieners were calculated based on prevailing retail prices of beef trimmings, gari, cellulose casings and all spices used in their manufacture at Columbus, USA at the time of this study. Wieners were weighed before and after final cooking, and cooking yield was determined as a percentage of final weight to initial weight.
Texture profile: Wieners were either warmed in a water bath at 90°C to attain internal temperatures of 60°C or allowed to thaw at 2°C (cold) and cored to obtain cylindrical samples measuring 24mm (height) by 16mm (width) for texture profiling using Instron 5542 Texture Analyzer (Instron Co., Canton, MA, USA) as described by [8].
Sensory profile: A 9-point Hedonic scale was used to assess the sensory profile of the wieners at the OSU Sensory Laboratory. In all, 150 regular wiener consumers assessed the products based on overall acceptability, flavour, texture and odour desirability on a 9-point Hedonic scale, where 9 represented “like extremely” and 1 represented “dislike extremely.” Wiener treatments were blind coded with random three-digit numbers and the order of serving samples to the consumers was randomized. Fifty consumers participated in each of three sessions of the evaluation process. The consumers comprised of students and staff of the Departments of Food Science and Technology and Animal Sciences, Columbus, OH, USA. The wieners were grilled (Star Grillmax Pro roller grill, Smithville, TN, USA) to internal temperatures of 60°C and cut into identical pieces of 3.0cm lengths and served to the consumers. The core temperature of the wieners was monitored during cooking with a 12- channel thermocouple scanning thermometer (model 92000-00) (Eutech Instruments Pte Ltd., Singapore), and approval to use human subjects for the consumer evaluation was granted by the Office of Responsible Research Practices, The Ohio State University, USA.
Statistical analysis: All data generated from the study were subjected to one-way analysis of variance (ANOVA) in a completely randomized design. Significant differences between treatments were determined at 5% by Scheffé multiple comparison using [11] for Windows.
Production cost, cooking yield and sensory profile
Results obtained for the costs of producing wieners, cooking yield and sensory profile are reported in Table 1. Using gari with the different levels of water to substitute portions of the meat in the formulation of wieners seemed to favour cooking yields at the 25% usage of water. However, the observed increases in cooking yields were not statistically significant (p>0.05). Product yields ranged from 88.17% (control) to 91.43% when gari was used with 25% in wiener production. Wiener cooking yields were 89.53% when 20% water was used with 3% gari, however when water was increased to 30%, the cooking yields reduced to 87.27%. This probably was an indication that the maximum water needed in wieners formulated with 3% gari should not exceed 25% in order to obtain optimum cooking yields. Although the differences in cooking yields were not statistically different, meat processors may possibly benefit more, in terms of product yields if GT25 was adopted in wiener formulations because meat products are sold all over the world on weight basis. Sensory evaluation of the wieners revealed similar trends in the attributes evaluated (Table 1). Whereas overall product acceptability and texture attributes were influenced significantly (p<0.05) by the use of gari at the different levels of hydration, wiener flavour and odour were not significantly different (p>0.05) from the control. The overall wiener acceptability score increased significantly (p<0.05) from 5.70 (control) to 6.88 when 3% gari was hydrated with 25% water. (Table 1)

It was also observed that texture attribute score, as assessed by the consumers improved significantly (p<0.05) at this level of hydration. Generally, all sensory attributes assessed by the consumers were higher at the 25% level of water usage in wiener formulations with gari.
Texture profile
Results of the TPA determinations are shown in Tables 2 and 3 for cold and warmed wieners respectively. With respect to the cold products, hardness, springiness, gumminess, chewiness and cohesiveness were all significantly different (p<0.05) among treatments. The control product was significantly (p<0.05) harder, more gummy and chewy compared to all the gari-treated wieners. The mean hardness of the cold products reduced significantly (p<0.05) from 5.51(0T20) to 2.93 (GT30), springiness reduced from 9.29 (0T20) to 8.55 (GT30) while gumminess reduced from 30.44 (0T20) to 12.98 (GT30). Both chewiness and cohesiveness of the cold wieners also reduced significantly (p<0.05) from 364.92 (0T20) to 155.55 (GT30) and 0.57 (control) to 0.43 (GT30) respectively, but adhesiveness was not significantly different (p>0.05) among treatments. (Table 2)

A comparison of the texture profile of cold and warmed wieners revealed further reductions when wieners were warmed to attain internal temperatures of 60°C before texture profiling Table 3. Furthermore, hardness, gumminess and chewiness reduced significantly (p<0.05) in all the products with 3% gari and the varying levels of water compared to the control. The levels of water used with 3% gari aided in better moisture retention due to the carbohydrate component in gari compared to the control without gari. Springiness, adhesiveness and cohesiveness were however not significantly different (p<0.05) among treatments. Hardness, springiness, gumminess, chewiness and adhesiveness of cold wieners reduced from 5.51(0T20) to 1.54 (GT30), 9.29 (0T20) to 7.84 (GT30), 30.44 (0T20) to 10.22 (GT30), 384.92 (0T20) to 102.09 (GT30), 9.20 (0T20) to 4.0 (GT30) respectively when wieners were warmed prior to TPA determinations. Warming the wieners probably resulted in melting the fat component and thus offering lesser resistance to rupture compared to the cold wieners. Thus, wieners will offer better eating quality when warmed before consumption compared to serving them cold. (Table 3)

Using gari in wieners had significant improvements in the sensory acceptability of the sausages. Though 3% gari in wiener formulations did not influence cooking yields, substantial savings were made on the costs of producing the wieners. Also, there were no adverse effects on flavour and odour of the wieners. More so, using gari in wieners formulations resulted in reduced hardness, gumminess and chewiness but had no influence on springiness, adhesiveness and cohesiveness. Furthermore, warming wieners resulted in reductions in their texture profiles. It was concluded that wieners could be produced with 3% gari and 25% water to obtain desirable texture and sensory profiles. We recommend that future studies should consider investigations on colour, storage ability and proximate composition of wieners produced with gari.
None.
No conflicts of interest.


To know more about our Journals....Iris Publishers
To know about Open Access Publishers

Iris Publishers- Open access Journal of Clinical & Medical Sciences | EXTERNAL CORTICAL FEMORAL IMPLANT IN A T.H.P A long term follow up of a Clinical Case




Authored by Yves Cirotteau


This article will show the clinical and surgical results of a patient who was operated of both hips for a severe coxarthrosis. The follow up is 30 years for the right hip and, and 26 years for the left hip. The woman was treated according to a new concept of the femoral stem. The goal of this concept is to respect-as close as possible-the physiological bone metabolism. The femoral implant, instead of being fixed in the medullary canal, is fixed on the femoral lateral cortex of the shaft to secure a fixation during all the patient’s life, whatever his age.

Abstract

The total Hip Arthroplasty of Sir John Charnley was a revolutionary step in the treatment of hip diseases. Currently, the long-term follow-up of such a prosthesis can be estimated from fifteen to twenty years. The question is: is that delay sufficient to treat young patients with severe hip disease. In a recent publication, Rik Huiskes claims that since Charnley, no so-called innovation has either scientific proof in real efficiency or in terms of longer longevity. This should not be a surprise for all total hip prothesis are placed in the medullary canal, either with or without cement. In fact, the so-called innovations are minimal modifications in the design of the stem. It is obvious that if these modifications are not efficient, one should not follow this line of research. It seems that almost everything has been written on total hip arthroplasty failure. We must therefore work in another direction, with other criteria.
Suppose that it is the bone, with all its specifications, which is the possible reason for that long-term failure. Is the “kuntscher” imperial road, the only highway to deal with the shaft of a long bone? A new concept, a new philosophy to fix a hip stem prosthesis on the femoral shaft becomes apparent. In other words, according to this new scientifically point of view, the mechanical aspect of a stem hip prothesis is no longer of interest. If the stem can be placed inside the medullary canal, why could not it be fixed outside of the shaft, for example on the external part of the diaphyseal cortex, below the periosteal layer? It seems that searcher should work today on bone physiology, instead of working on any mechanical aspect of surgical fixation in the medullary canal. Using the physiological properties of a living bone could be the answer to avoid any failure of the stem all the life’s patient long.

Pathological Modifications of the Femoral Cortices

Everyone, in his practice, had patients with more or less severe brain dysfunction, one is hemiplegia [1]. What could happen for the patient from an orthopedic point of view, on the lower limb when such a disease happens? The reduced use of the limb reduces the pressure on the bearing bone and, from a physiological point of view, a reduction of the mineralization. The bone becomes osteoporotic [2]. The physical phenomenon is reversible when the pressure conditions are restored. Here are two examples. This patient had a right haemorrhagic stroke few years ago. He had a left hemiplegia and spent a long time in physiotherapy due to the difficulty to walk. Note the thin both femoral cortical due to the bad utilization of the left lower limb (Figure a). Few years later, he recovered a best walk. Note the very good thickening due to the best support of his body weight by the limb (Figure b). Adversingly, despite the severe coxarthrosis note the good thickness of the femoral cortex before surgery (Figure a, b). Few years later the patient had a hemiplegia. Note the increasing diameter of the femoral medullary canal (Figure c). What would have happened if an intramedullary implant was settle in it?

Scientific Reasons of this New Concept

The choice of this implant’s design was done in the aim of a more physiological respect of the bone structures [3-5].
a) The joint elasticity is mainly due to the cancellous bone of a joint. Most of the intra-medullary canal implants destroy it. In this case the cancellous bone is in the upper femoral metaphyseal neck, more or less in totality (Figure a, b).
b) The bone marrow has one of the most important roles in bone physiology: vascularization, cells of bone remodeling, blood cells, proteins and minerals are the major actors of the normal bone life.
c) The periosteum is acting all lifelong (even after 100 years) and covers all foreign bodies which are fixed on the shaft, keeping a fixation stronger and stronger by time (Figure c, d).
d) The pressure on the calcar is necessary to increase and maintain it thickness. A large crown on the upper part of the implant rests firmly there so that there is no resorption [8-9].

Minimal Resection of the Cancellous Bone

To fix in the upper femoral metaphysis the prothesis needs a very few cancellous bone removals as shown on the drawing. It keeps the elasticity of this part of the femur (Figure a, b).

Technical procedure
A cemented Charnley’s cup in polyethylene was cemented in the acetabulum. An external stem implant in titanium was fixed on the lateral cortex of the femoral shaft, below the periosteum. A 22,2 mm diameter of the head was used on the right side. Four years later, a non-cemented metal back acetabulum with a 22,2 diameter of the head was placed on the left side. Insert in polyethylene. A lateral femoral Implant in titanium was screwed. Screws of 5 mm of diameter for the femoral shaft, 6 mm of diameter to fix the greater trochanter.
Clinical story and examination
Me T… Françoise is Born the 04 12 1938 - Her Height is 1.59m, her Weight is 59kg. This 80-year-old patient had a bilateral coxarthrosis. When she was 51 years old, in 1989, she was operated on the left side. Four years later, a THP as placed on the right side in 1993. She was seen in clinic office in May 2019. Follow up: 30 years on the right side Follow up: 26 years on the left side She has no pain. She can climb stairs up and down without difficulty. Over three floors, she uses the ramp stairs. She walks without help as long as she wants. One hour without stop She walks without limping.
PM: One hour, without stop in a quiet walk. She has a normal life.
She practices Sports Taï chi twice a weel, one hour with other members.
She goes in holydays either vacancies aux Canaries, Greece, dans les Pyrénées, 0 Saint Jean de luz. She is a grand-ma keeper for her Little children’s daughter on sunday.
She Plays piano, and sing in a chorus opera
She Has a lot of additional activities
Mobility: Left: 140 0 - 35 20 - 20 20
Right: 140 0 - 40 40 - 30 20
Functional scores
Postel-Merle d’Aubigné (PMA) Pain, Mobility, Walk 4 grades: 18 excellent. Harris hip score: Douleur, function, mobilité, absence de déformation Score jusquà 100: 90-100: excellent. Oxford hip score: Activities of the daily Life. Auto-administrated survey with12 items giving a score: 42-48: excellent.

Discussion

The first planning was to start with a well-considered definition of the goal expected. It was to secure the femoral implant on its support so that it would stay all day long, as long as patient’s life, without physical activity limitation. The second question was followed by the development of an effective strategy. Once establishing the goal and the strategy, do we have worked backwards to identify the next steps? Have we reach the goal expected? Can we be sure that the fémoral implant will be aware of complications in 100%.
In fact, the purpose is to answer to three questions:
a. Does bone physiology have been respected? The answer is yes concerning the cancellous bone, the femoral cortices, the role of the periosteum. There was no calcar resorption.
b. Do we have had any mechanical complications such as: broken screws or broken plates. Yes, in a very small cases, some screws fixing the greater trochanter broke. If the osteotomy of this apophysis is consolidated, nothing will happen. In some case the lateral part of the broken screws must be removed when painful. Since we have changed the design of the screws, (6 mm of diameter) no one broke. Have we reach the goal? In this experience, the answer is yes [4]. Not any femoral plate was removed. All patients are either too old now or are in a very high place in the sky where nobody can reach them or are still living with their implants.

Conclusion

The lateral femoral implant is, according to this cohorte, one of the good solutions for a long implant’s life, as long as the patient’s life, whatever his age [5-7]. But we should stress the difficulty of its fixation on the upper femoral metaphysis. The greater trochanteric osteotomy must be perfect. The screws must be of a good size and length. The consolidation delay of this bone section must be respected. The patient must walk with two crutches during this time with only a contact support. Surgeon must keep in mind that he is not at all a simple machine to operate. He must practice with his heart and must explain to his patient what he will do and why he will do for it in order to reach the target [9]. In this way, the surgeon does not destroy the intra-medullary bone marrow. He keeps as much as possible the cervical cancellous bone (Figure a, b). The implant applies a constant pressure on the femoral calcar [8], and the periosteum osteogenic power covers by time the implant plate, connecting strongly mechanically both bone and metal. This patient is in good health, has a normal activity for her age. Both femoral implants remain stable and will stay so until the end of the story.

Acknowledgment

None.

Conflict of Interest

No conflict of Interest.


To read more about this article.... Open access Journal of Clinical & Medical Sciences

Please follow the URL to access more information about this article
https://irispublishers.com/ctcms/fulltext/external-cortical-femoral-implant-in-a-thp-a-long-term-follow-up-of-a-clinical-case.ID.000510.php


To know more about our Journals....Iris Publishers
To know about Open Access publisher

Iris Publishers-Open access Journal of Hydrology & Meteorology | Influence of Community Resilience to Flood Risk and Coping Strategies in Bayelsa State, Southern Nigeria

  Authored by  Nwankwoala HO *, Abstract This study is aimed at assessing the influence of community resilience to flood risk and coping str...