[Quality control of antibiotics used in Senegal]

To slow the spread of bacterial resistance and promote safety in the use of medicines, development of quality control tools is indispensable. The purpose of this study was to evaluate the quality of several antibiotic agents used in Senegal and to assess the utility of the mini laboratory as a quality control tool. The mini laboratory and all materials necessary for this study were provided by the German Pharma Health Fund. A total of 34 antibiotic samples were submitted to a battery of tests including physical and visual inspection, disintegration, and thin layer chromatography designed for identification and semiquantitative evaluation. Non-conformities detected by physical and visual inspection were found mainly in products from the illicit sector (80%) but some non-conformities were also found in products from licit private sector (20%). Based on thin layer chromatography findings, non-conformities in product identity and dosage involved mainly erythromycin (45%) followed by amoxicillin and ciprofloxacin (22% each). Again this type of non-conformity was most frequent in products from the illicit sector (45%) but it was also observed in products from the private and public sectors (33% and 22% respectively). These findings show that follow-up is necessary to ensure the quality of medicines, especially antibiotics. In this study the mini laboratory was a highly useful quality control tool.

[Control of the quality of antiretroviral medicines used in Senegal]

INTRODUCTION

Success of any program to fight AIDS passes through out quality of antiretroviral medicines. The control and follow-up of the quality of these medicines constitute essential levers to guarantee quality. Our study aims to evaluate the quality of antiretroviral medicines used in Senegal by means of a mini laboratory from the German Pharmaceutical Health Fund.

MATERIALS AND METHODS

The mini laboratory provides technical arsenal necessary for the analysis. To sum up, 43 samples of antiretroviral medicines have been submitted to three types of simple, quick and reliable tests which are physical and visual inspection, disintegration and thin layer chromatography.

RESULTS

The obtained results give at physical and visual inspection, 9.3% of samples which are not similar. 30 samples out of 32 have a good disintegration time. About 11.6% of samples are not similar to thin layer chromatography.

CONCLUSION

The control of the quality of antiretroviral medicines is necessary if we consider the number of no conform cases which are relatively important. The mini laboratory can constitute an interesting tool for technical control facilities in developing countries that suffer from a real lack of materials.

[Study of the contents in fat, in protein and in vitamin D of powdered milk varieties sold in Dakar]

INTRODUCTION

The powdered milk is a much appreciated food in Senegal. However no particular control is realized by authorities on the various marks of milk imported before their marketing. In the concern to protect the health of the consumers, but especially in front of the very big variety of the sources of supply in this product we determined the contents in fat, in protein and in vitamin D main variety show of marketed powdered milk Dakar.

MATERIAL AND METHODS

Chemical methods were operated to determine the fat contents and in proteins. The liquid chromatography in high performance was used to identify and measure the vitamin D.

RESULTS

The obtained results profits showed that all the studied samples of milk had contents in fat included between 25 and 31 g %, those in proteins were included between 23 and 25 g %. As regards the dosage of the vitamin D, a single sample had content weaker than that mentioned on the packaging by the manufacturer.

CONCLUSION

The results of this study allowed to notice most of the variety varieties of powdered milk marketed in Dakar were in accordance with the standards established for this food and are consequently good quality.

Carboxypeptidases B of Anopheles gambiae as targets for a Plasmodium falciparum transmission-blocking vaccine

Anopheles gambiae is the major African vector of Plasmodium falciparum, the most deadly species of human malaria parasite and the most prevalent in Africa. Several strategies are being developed to limit the global impact of malaria via reducing transmission rates, among which are transmission-blocking vaccines (TBVs), which induce in the vertebrate host the production of antibodies that inhibit parasite development in the mosquito midgut. So far, the most promising components of a TBV are parasite-derived antigens, although targeting critical mosquito components might also successfully block development of the parasite in its vector. We previously identified A. gambiae genes whose expression was modified in P. falciparum-infected mosquitoes, including one midgut carboxypeptidase gene, cpbAg1. Here we show that P. falciparum up-regulates the expression of cpbAg1 and of a second midgut carboxypeptidase gene, cpbAg2, and that this up-regulation correlates with an increased carboxypeptidase B (CPB) activity at a time when parasites establish infection in the mosquito midgut. The addition of antibodies directed against CPBAg1 to a P. falciparum-containing blood meal inhibited CPB activity and blocked parasite development in the mosquito midgut. Furthermore, the development of the rodent parasite Plasmodium berghei was significantly reduced in mosquitoes fed on infected mice that had been immunized with recombinant CPBAg1. Lastly, mosquitoes fed on anti-CPBAg1 antibodies exhibited reduced reproductive capacity, a secondary effect of a CPB-based TBV that could likely contribute to reducing Plasmodium transmission. These results indicate that A. gambiae CPBs could constitute targets for a TBV that is based upon mosquito molecules.

[Malaria morbidity in Barkedji, village of Ferlo, in Senegal Sahelian area]

A study of malaria morbidity was carried out from November 1994 to October 1995, in a Ferlo village (Barkedji) characterized by a long persistence of the temporary ponds. The objective was to evaluate the repercussions of the strong and long anopheles transmission in humans. A clinical follow-up of a group of residents was conducted at home every 10 days by an investigator trained for taking axillary temperature and making thick smears, when suspecting malaria. Were included in the group, 123 voluntary subjects among whom 50% were children under 10 years old. Any feverish subject (T degree >37 degrees 5) or subject presenting other malaria symptoms (headaches, hot body shivers, sweats, aches...) was regarded as having a malaria attack as well as a parasitemia >2500 P/mm3 in children aged of 0 to 14 years old and 1000 P/mm3 in the oldest. During the study subjects with at least one feverish access, plasmodium infection and malaria attack were 58%, 33% and 22%, respectively. On 172 hyperthermias observed, 49% were accompanied by a circulating parasitemia and 30% corresponded to malaria attack. The feverish subjects (74% vs. 42%), the subjects with parasitemia (51% vs. 16%) and the cases of malaria (34% vs. 10%) were more frequently encountered in children under10 than in the oldest. The cases of malaria attacks were more frequent from November to January (70%). The strong intensity of malaria transmission in Barkedji and the persistence of its temporary ponds until January were sufficient to influence the level of malaria morbidity and consequently the development of an anti-malaria immunity by the indigenous population.

[Contribution of the study of evolution of major electrolytes contents in the aqueous humour by X-ray fluorescence and ICP/AES]

INTRODUCTION

In the scope of this study, we had to do a qualitative and quantitative research of the current electrolytes as part of aqueous humour samples taken from patients suffering from cataract.

MATERIALS AND METHOD

The tests were carried out by X-ray fluorescence and ICP/AES. The detection limit for the electrolytes varied from 0.005 to 0.1 ppm.

RESULTS

The test results show iron (minimum 0.82ppm; maximum 25.50ppm), copper (0.28ppm; 8.17ppm), brome (5.18 ppm ; 55.82ppm), zinc (0.70ppm ; 9.78ppm ), sodium (1274.83ppm, 5211.67 ppm), potassium (55.52ppm ; 255.02ppm), calcium (26.46 ppm ; 256.81ppm), magnesium (5.77ppm; 70.33ppm).

CONCLUSION

The data study have enabled us to establish reference value for each electrolyte. Study of the comparative reference values, together with the contents found in the normal aqueous humour, the normal and pathologic crystalline lens, has shown a noticeably low concentration of electrolytes and breakdown of the sodium/potassium pump which ensures ionic exchange between aqueous humour and the crystalline lens.

Influence of glenohumeral mismatch on bone strains and implant displacements in implanted glenoïds. An in vitro experimental study on cadaveric scapulae

In shoulder arthroplasty, there is no consensus about the ideal mismatch between a prosthetic humeral head and a glenoïd component. Thus, investigations into mismatch effects from a biomechanical point of view can be useful. The aim of this in vitro study was to help us understand mismatch influence on bone strains, translational forces in the joint and implant/bone displacements in implanted scapulae. Five fresh cadaveric scapulae were implanted with a cemented keeled polyethylene implant. The lower part of the scapulae was embedded and the loadings were carried out using five metallic spheres simulating mismatches of 0, 2, 4, 5 and 6 mm. Loadings included a constant compressive preload of 392N and an anterior, posterior, inferior and superior translation of 2.5 mm. We measured the transversal force necessary to produce the imposed translation, the strains at six locations around the peripheral cortex of the glenoïd using strain gages and the relative implant/bone displacements using CCD cameras. Generally, the increase of mismatch reduced the translational forces, the strains around the glenoïd and, except for the anterior loading, the relative implant/bone displacements. Few and even no significant differences were observed when the mismatch varied from 0 to 2 mm; the number of significant differences increased when the mismatch varied from 0 to 4mm and from 0 to 5 mm; the results obtained for a 0-6 mm variation in mismatch were comparable to those obtained for a 0-5 mm variation. This study underlines that the mismatch has a significant effect on bone strains, relative implant/bone displacements and induced translational forces when a compressive preload and imposed translations were applied on implanted scapulae.

A 3D finite element model of an implanted scapula: importance of a multiparametric validation using experimental data

In order to help to understand the loosening phenomenon around glenoïd prostheses, a 3D finite element model of a previously tested implanted scapula has been developed. The construction of the model was done using CT scans of the tested scapula. Different bone material properties were tested and shell elements or 8 nodes hexaedric elements were used to model the cortical bone. Surface contact elements were introduced on one hand between the bone and the lower part of the plate of the implant, and on the other, between the loading metallic ball and the upper surface of the implant. The results of the model were compared with those issued from in vitro experiments carried out on the same scapula. The evaluation of the model was done for nine cases of loading of 500 N distributed on the implant, in terms of strains (principal strains of six spots around peripheral cortex of the glenoïd) and displacement of four points positioned on the implant. The best configuration of the model presented here, fits with experiments for most of the strains (difference lower than 150microdef) but it seems to be still too stiff (mainly in the lower part). Nevertheless, we want, in this paper, to underline the importance of doing a multiparametric validation for such a model. Indeed, some models can give correct results for one case of loading but bad results for another kind of loading, some others can give good results for one kind of compared parameters (like strains for instance) but bad results for the other one (like displacements).

[Complications of treatment of adult's groin hernia: a report of 100 cases comparative study between Bassini and Mac Vay's technics]

The authors report a prospective study comparing pre and immediate post operative complications of non complicated hernia of the groin in adult treated by operations based on Bassini and Mac Vay technics. It concerned a total of 100 patients made up of two groups of 50 age ranging from 13 to 84 years with an average age of 47 years of whom were 93 males and 7 females. No mortality was registered. The rate of complications was 20% in Bassini's technic and 22% in Mac Vay's technic. There were: bladder injurie, accidental skin wound incurred by the electric surgical blade, meningeal irritation, urinary retention, scrotal sac hematoma, parietal suppuration, intestinal occlusion and immediate recidivation before 6 months. As well as our study as in literature, specific complications related to both technics were rare. We could draw the conlusion that there is no significant superiority of one technic in comparison with the other one.

[Apical foramen position on mesio buccal root of the maxillary first molar. Study in Senegalese population]

The maxillary first molar is submitted to frequent endodontic treatment and more over, it presents the highest failure rates, often in relation with his mesio-buccal root. Several studies about failures factors showed implication of root canal anatomy often in relation with the frequency of second canal. However, other failures factors, as the foramen situation, which is very important in endodontic practice, could increase the failure rate. The aim of this study was to determine the foramen situation in Senegalese people. The results showed 63.85% of excentric foramina (83 out of 130). 86% of excentric foramina were located at 1.5mm radiology apex.

[Role of Anopheles melas Theobald (1903) on malaria transmission in a mangrove swamp in Saloum (Senegal)]

From June 1995 to January 1998, entomological studies carried out in five villages located in the Delta's Saloum have allowed to better understand the contribution of An. melas Theobald (1903) to malaria transmission in mangrove swamp. Among the five villages studied, three of them (Simal, Djilor and Marlothie) located along the Saloum river, are colonised by An. arabiensis; the two others (Djifere and Diakhanor) located between the sea and the river, are colonised by An. melas. During the rainy season and at the beginning of the dry season, An. melas and An. arabiensis are sympatric. The ratio of An. melas/An. arabiensis increases when we go closer the coast where An. melas becomes quite exclusive. When An. melas is predominant, endophagy, endophily and anthropophily are very marked. The parturity rates are lower in An. melas than in An. arabiensis. In the predominance area of each species, transmission is on the same level. During the period of sympatry, An. arabiensis is responsible for the transmission and when it is absent, An. melas carries on. Transmission occurs from July to March with a maximum at the beginning of the dry season. In the villages of the mangrove swamp, its prolongation until the middle of the dry season is due to An. melas.

In vitro biomechanical analysis of glenoïds before and after implantation of prosthetic components

Biomechanical investigations are yet necessary to better understand the origin of the glenoïd loosening which is the main reason for revision surgery. The aim of this study was to analyse the behaviour of cadaveric glenoïds before and after implantation of glenoïd prostheses. For that, we developed a new experimental protocol allowing measurement of bone strains and implants displacements under various loading cases. Ten pairs of fresh cadaveric scapulae were tested. Two kinds of loads were applied on the intact glenoïd: physiological loads corresponding to a 0-180 degrees abduction and anteflexion movements, and 500N loads. The glenoïds were then implanted with a keeled or pegged cemented polyethylene implant. The same previous 500N loads were then applied on the implanted glenoïds. Strains were measured using six strain gages placed on precise points around the peripheral cortex of the glenoïd. Displacements of implants under loading were measured using two CCD cameras. Maximum strains were obtained between 60 degrees and 120 degrees of abduction or anteflexion. They were located at the anterior and antero-superior parts of the glenoïd during abduction and at the posterior and postero-superior parts during anteflexion. Implantation of a prosthetic component generally seemed to increase strains, but tensile strains were decreased at the postero-inferior part with the antero-inferior loading point.Some differences were observed between the implants, but they have to be confirmed by further experiments. The great number of data obtained for intact scapulae could be used for a better understanding of glenoïd behaviour and for validation of finite element models.

[Long term course after thyroidectomy for euthyroid nodular goiter]

Every patient operated for nodular goiter by a partial surgery is exposed to recurrence. In order to verify this idea, the authors followed 36 patients operated on for nodulargoiterat least 10 years ago. A clinical examination for all the patients and echographic study for 24 of them allowed the detection of recurrence and the evaluation of survival and recurrence without any opotherapy. It seemed that clinical recurrence is observed in 16.65% of cases whereas echographic study revealed recurrence in 50% of patients examined. Only two patients were reoperated on. The predictive factors of the recurrence are geographic endemic origin and ethny, partial surgery and vesicular goiters. With 66.65% of survival without recurrence at 18 years without opotherapy, the authors argue about the utility of such treatment.

[Role of elastic compression in the treatment of postphlebitic leg ulcers at the University Hospital of Dakar: report of 20 cases]

Varicose disease and venous thrombosis were reputed exceptional among black africans and almost all leg ulcers were called "tropical". We have treated 20 cases of postphlebitic ulcers in the teaching hospital of Dakar between march 1989 and december 1992. There were 12 men and 8 women. Mean age was 40 years (24 to 60 years). The initial venous thrombosis dated at mean 8 +/- 3 years. It was confirmed in a hospital in 10 cases and found in the medical history of all patients. All patients presented leg ulcers with non systematised venous varicose and trophic troubles. The ulcers treated only by dressings lasted a duration of 4 months (2 weeks to 9 months) without healing. In view of this failure we have added an ambulatory elastic contention with elastic bandage putted on at hospital after that biweekly dressing until cicatrisation followed by putting elastic socking with degressive compression. We have observed a quickly cicatrisation in mean time of 4 weeks (2 to 6 weeks) with good tolerance of socking. Only 3 patients showed recurrence. Elastic contention has a great place in the treatment of postphlebitic ulcers which are not that exceptional among black Africans.

An in vitro biomechanical study of bone plate and interlocking nail in a canine diaphyseal femoral fracture model

OBJECTIVE

To compare the structural properties and the interfragmentary motion in ostectomized canine femurs stabilized with either an 8-mm interlocking nail system (IN) or a 10-hole dynamic compression broad plate (DCP).

ANIMAL OR SAMPLE POPULATION

Ten pairs of adult canine femurs with a 25-mm mid-diaphyseal gap.

METHODS

Bone specimens were divided into 2 groups (10 femurs each). Left femurs were stabilized with a DCP and 8 bicortical screws; right femurs were stabilized with an IN and 3 screws. Mechanical tests were performed in eccentric axial loading and in craniocaudal bending. The testing was first conducted nondestructively and then until breakage. Structural properties, ie, stiffness, yield limits, and failure limits, were determined. Interfragmentary motion was measured during nondestructive tests with the use of an optoelectronic device. Axial, transverse, and rotational motions were calculated. Mean values of stiffness, yield and failure limits, and axial and shear motions for each fixation method were compared using a paired t test within each group (P <.05).

RESULTS

Mean (+/-SD) values of stiffness and failure limit were significantly higher for IN constructs than for DCP constructs in compression, while there was little difference in the results between each tested group in bending. Mean yield load values were significantly higher for IN than for DCP specimens in compression as well as in bending. The axial-motion analysis revealed significant differences between IN and DCP groups during bending tests only. The highest score of transverse motion at the gap was recorded during bending tests, and was higher for DCP than for IN specimens. There were insignificant differences between the two groups with regard to rotation around the diaphyseal axis.

CONCLUSIONS AND CLINICAL RELEVANCE

Structural properties and interfragmentary shear motion analysis demonstrated a much higher rigidity in the IN-bone than in the DCP-bone constructs.

[Efficacy of the combination of DEET (20%) and EHD (15%) against mosquito bites. Results of a study carried out in Senegal]

The authors report the results of a survey on the efficacy against mosquito bites of a repellent, Mousticologne Spécial Zones Infestées (DEET 20%, EHD 15%). Two forms of the product, spray and gel, were tested in Senegal. Repellent efficacy was evaluated by exposing volunteers, both repellent-treated and untreated, to mosquito bites. The number of mosquito bites per person and per night was 0.63 in the spray treated group (group 1), 6.03 in the gel treated group (group 2) and 94.17 in the untreated group (group 3). The analysis of these results showed a significant difference between treated and untreated persons. Untreated persons were not protected against mosquito bites, persons treated with the spray were protected for 12 hours and those treated with the gel had over 8 hours' protection. We concluded that a single application of the repellent Mousticologne in the field is capable of ensuring all-night protection against mosquito bites.

[Predictive ultrasonographic criteria for portal hypertension due to Schistosoma mansoni in a recently established endemiz zone]

The first cases of Schistosoma mansoni infection were reported in the Senegal River Basin ten years ago. Today endemicity is so high that prevalence rates exceed 90 p. 100 in some areas. Schistosomiasis sometimes goes undiagnosed until the occurrence of portal hypertension with rupture of esophageal varices. Endoscopy is the gold standard for detection of esophageal varices but it is impractical in remote areas. Ultrasonography has been proposed as a non-invasive alternative. The purpose of this study is to describe the results of simultaneous endoscopic and ultrasonographic assessment in 101 subjects from the Richard-Toll area of the Senegal River Basin. Findings showed that severe forms of schistosomiasis complicated by portal hypertension were already present in the region less 10 years after description of the first case. This study also proposes a diagnostic score for portal hypertension based on ultrasonographic findings. The features included in this score are thickening of portal vessel walls, portal vessel diameter, and collapsed appearance of the splenic vein during inspiration. In our hands this score allowed reliable prediction of the development of esophageal varices. Ultrasonography is a good tool for identifying severe forms of schistosomiasis. It should be useful for routine screening in recently established endemic zones.

An experimental study of ring avulsion injuries and two preventive devices

We have performed biomechanical experiments on fresh cadaveric fingers to test two modifications to normal rings which may prevent ring avulsion injuries. One of these modifications produced reliable protection against ring avulsion accidents and was undetectable. It thus does not reduce the symbolic value of a wedding ring.

[In vivo study of kinematics of the elbow using electromagnetic goniometer]

We used an electromagnetic goniometer to study the angular and translations displacements between the humerus and the 2 bones of the forearm. The electromagnetic gionometer allows acquisition of the coordinates and analysis of the 6 degrees of motion. To validate our external fixation apparatus, we used a fresh body upper limb. At first, a series of measurements was conducted with the apparatus. We then performed a series of measurements, by fixing the transmitter and receiver with external fixation pins directly inserted into the bones of the arm and forearm. To assess the reproducibility of our method, we chose a healthy subject. We performed 20 measurements over his right and left elbows. In order to study normal elbow kinematics, we performed measurements on 10 healthy subjects. The study of rotation showed that the apparatus was adapted to measure flexion-extension. It limited pronation-supination movement to about 26.7 degrees. Abduction was increased by 19.7 degrees by our apparatus during flexion-extension, but abduction was reliable within a 2 degrees range for pronation-supination. The sliding movements recorded during flexion-extension were reliable within approximately 3 mm for frontal translations, 6 mm for fitting, and 1 mm for external translations. For the sliding movements recorded in pronation-supination, frontal translations were reliable within about 7 mm, fitting was reliable within 1.9 mm and external translations were reliable within about 2.9 mm. During flexion-extension of the elbow, flexion-extension, frontal translations and external translations were reproducible. The reproducibility test showed that only 6 measurements were reproducible. The kinematic elbow study of a healthy subject showed that the average amplitude of flexion-extension was close to the measurement observed with the manual goniometer. The results in the healthy subject showed that the elbow is more stable during pronation-supination than during flexion-extension. This preliminary study should allow us, in the near future, to study elbow prosthesis kinematics.