Biomedical subjects

A Diop

Publications and source records attributed to A Diop.

At least 37 records · Page 2Linked to original sources

PubMed1999

[Zoophagia and alternative host selection of the marlaia vectors in Senegal].

Blood-engorged females of An. gambiae s.l., An. funestus, An. pharoensis and An. rufipes caught resting indoors were tested (precipitin or enzyme-linked immunosorbent assay) to determine the source of bloodmeal. The species of the An. gambiae complex fed mainly on human hosts in all prospected areas, except in those of the mid Senegal river valley where an important zoophily was observed within and near the irrigation zone. Among 4,597 blood-engorged females of An. gambiae s.l., 29% fed on cattle with 7.5% of mixed boodmeals, mainly human-bovine or human-equine. The presence of cattle, culicid population densities and individual mosquito safety devices were the most determinant factors of animal deviation. Blood of most domestic animals was found in the stomach of collected females, but according to areas, bovines and equines were the main hosts for zoophilic females of An. gambiae s.l. Females of An. funestus collected in the middle-west were more anthropophilic than those collected in south-eastern areas. An. pharoensis was most prevalent in the Senegal river delta where it was found to be very anthropophilic. An. rufipes was strongly endophilic but exclusively zoophilic in all prospected areas.

Animals↗

PubMed1998

Characterization of the mechanical behaviour parameters of the costo-vertebral joint.

This in vitro study introduces a new method to determine quantitative parameters characterizing the mechanical behaviour of the costo-vertebral joint. These parameters are useful in building numerical models of the thoracic spine, taking into account the thoracic cage. Nine thoracic cages were isolated from fresh human cadavers. From each cage, three functional units were tested: T1-T2, T5-T6, T9-T10. Loads were applied according to the joint local coordinate system. Every functional unit was tested first intact and again after section of successive costo-transverse ligaments. We used an opto-electronic system to follow the three-dimensional motion of the joint, and obtained non-linear load/displacement curves according to the primary rotation axis. A statistical analysis of these curves allowed the calculation of parameters describing the joint mechanical behaviour: total range of motion, motion in the low-stiffness zone, and flexibilities in the positive and negative quasi-linear zones. These values can be used as a database for mechanical modeling of the spine.

Adult↗

PubMed1998

[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.

Cadaver↗

PubMed1998

[Impact of the use of permethrin pre-impregnated mosquito nets on malaria transmission in a hyperendemic village of Senegal].

The efficacy of permethrin-treated bednets was evaluated in Wassadou, a hyperendemic village located in the Sudanese grasslands of southeast Senegal. Pretreatment data were collected between 1992 and 1993. Bednets were distributed to the whole population in June 1995 and impact of their use on vector populations and malaria transmission was evaluated until November 1995. This period corresponds to the rainy season during which malaria transmission is highest. Data were compared with a control village in which bednets were not distributed. Findings showed that use of bednets led to a sharp decrease in the density of the vector population and malaria transmission. The number of bites by Anopheles gambiae s.1. decreased 69%. The density of blood-laden and pregnant females inside dwellings decreased 91% and 96% respectively. The sporozoite index of females captured on the skin decreased 76% and the daily rate of entomological inoculation decreased 88%. This impact was not great enough to eliminate the risk of infection. Prolonged study over a period of 4 to 5 years is needed to evaluate the impact of long-term use of insecticide-treated bednets on vector population and malaria transmission.

Animals↗

PubMed1998

[Well water pollution in the Khombole district: research on the contamination by organochlorine pesticide residues and organic substances (feces)].

The study realized in the district of Khombole (SENEGAL) has permit to estimate the contamination levels of wells waters used by the populations. The research and the dosage of the organichlorine pesticide residues, nitrites and nitrates and microbiologic analysis have been done on 19 wells chosen after a drawning of lots. The organochlorine pesticide residues which have been found prove that the wells are permanently exposed to these chemical substances which don't constitute nevertheless a major risk for the populations health. The results of our research proved also that there is a real risk of intoxication with the nitrogen oxides. In effects more than 50% of the wells have revealed nitrates contents up to the indicative value (25 mg/l). As for the nitrates, with a few exceptions (5/18), the contents are superior to the authorized norm (0.1 mg/l). By another way the bacteriologic analysis has revealed in the one hand a DBT (Total Bacterian Count) up to 10,000 germs/l for all the wells, and in the other hand the presence of Escherichia coli, Enterococcus faecalis that confirm a faecal contamination.

Colony Count, Microbial↗

PubMed1998

[A left paraduodenal hernia--a case report].

The left paraduodenal hernia obtains when the small intestine goes through the left paraduodenal fosset. It (the hernia) develops on the left, at the back of the descending mesocolon. The present authors study one case looking at its pathogeny and the clinical and therapeutic problems posed by such a variety of congenital internal hernia. The authors emphasize, in particular, its morbid associations with the volvulus of the pelvic colon. Finally they highlight the importance of a through and careful exploration of the abdominal cavity during any laparatomy following an occlusive syndrome.

Abdominal Pain↗

PubMed1998

[Evaluation of parasitic risks for the population bordering on the Mbeubeuss public waste disposal, Dakar].

The authors carried out a parasitologic survey on 367 inhabitants of Malika, a village located in the immediate surroundings of M'Beubeuss disposal, as well as on 433 other residents of Keur Massar, a location 2 km farther, in order to assess parasitic hazards encountered by people neighbouring this disposal. As far as intestinal parasitosis are concerned, the prevalence rate was significantly higher in Malika (61.3%) than in Keur Massar (48.5%) The sex, social and economic status, level of education as well as the time of dwelling in the neighbouring area were identified as the risk factors of intestinal parasitism. Only the last one can be considered as significantly and independently related to a risk of intestinal parasitism. As for malaria, the plasmodial index in Malika was 6% versus 7.6% in Keur Massar (no significant difference). Thus, if it does exist for neighbouring people, an infestation risk by intestinal parasites related to exposure duration, contrarily, it does not exist for malaria. Appropriate steps should be taken to prevent the hazards encountered by inhabitants of surrounding villages.

Adolescent↗

PubMed1998

[Total vaginal hysterectomy for genital prolapse apropos of 10 cases].

There are many variants in vaginal hysterectomy procedures owing to precises indications. We have performed a total vaginal hysterectomy procedure which technique is described herein. Our procedure was using the preexisting anatomic structures. It allows a solid cure adapted to each compound of the genital prolapse. Among a series of 10 cases, we report few complications. An important peroperative bleeding occurred in one case. The postoperative morbidity included 1 case of genital infection and 1 case of urinary fistula. One patient died from a cause not reliable to the procedure. The mean duration of the hospital stay was 10 days. After 2 years follow up, 9 of our patients have good anatomical and functional results. The shortness of this series does not allow us to concluded definitively. However, our results are comparable with those reported in the literature.

Evaluation Studies as Topic↗

PubMed1998

[Establishing a strain of Anopheles arabiensis (Diptera:Culicidae) in an insectarium].

For the first time in Dakar (Senegal), we managed to establish a local colony of Anopheles arabiensis (Diptera: Culicidae) in insectarium. The observations on the productivity of the colony showed a gradual adaptation of the preimaginal stages to insectarium conditions. The estimated duration of the development of the various preimaginal stages showed an interval of 24 hours for egg hatching, 48 h for stage I, 24 h for stage II, 24 h for stage III and 36 h for the pupal stage. Stage IV which makes the difference in the duration of the adult-egg cycle, varied from 1 to 13 days. Pupal moulting occurred mainly between 11 h and 19 h, with a peak between 14 h and 15 h. The duration of the preimaginal cycle in insectarium was from 8 to 11 days. This fits with the duration shown in natural breeding places during the rainy season (the best period for the development) which was from 9.5 to 13.3 days. Emergence, faster in males, occurred in the evening around 6.30-7 p.m. The emergence rate was higher in insectarium (92.9%) compared with that shown in the field (6 to 20%) (the natural breeding places are subject to biological and biochemical variations and to predators's action). The sex-ratio is equal to 1. The studies in insectarium showed that the gonotrophic cycle is 3 days in neonate blood fed after day 2 and also in parous ones. This cycle is 5 days in nulliparous with pregravid stage. The average longevity is 16 days with a maximum of 26 days in females and 43 days in males.

Animals↗

PubMed1997

Comparison of behavior and vector efficiency of Anopheles gambiae and An. arabiensis (Diptera:Culicidae) in Barkedji, a Sahelian area of Senegal.

The ecology, population dynamics, and malaria vector efficiency of Anopheles gambiae and An. arabiensis were studied for 2 yr in a Sahelian village of Senegal. Anophelines were captured at human bait and resting indoors by pyrethrum spray. Mosquitoes belonging to the An. gambiae complex were identified by polymerase chain reaction. Of 26,973 females, An. arabiensis represented 79% of the mosquitoes captured and remained in the study area longer than An. gambiae after the rains terminated. There were no differences in nocturnal biting cycles or endophagous rates between An. gambiae and An. arabiensis. Based on an enzyme-linked immunosorbent assay test of bloodmeals, the anthropophilic rate of these 2 vectors were both approximately 60%, when comparisons were made during the same period. Overall, 18% of the resting females had patent mixed bloodmeals, mainly human-bovine. The parity rates of An. gambiae and An. arabiensis varied temporally. Despite similar behavior, the Plasmodium falciparum circumsporozoite protein (CSP) rates were different between An. gambiae (4.1%) and An. arabiensis (1.3%). P. malariae and P. ovale only represented 4% of the total Plasmodium identified in mosquitoes. Transmission was seasonal, occurring mainly during 4 mo. The CSP entomological inoculation rates were 128 bites per human per year for the 1st yr and 100 for the 2nd yr. Because of the combination of a high human biting rate and a low CSP rate, An. arabiensis accounted for 63% of transmission. Possible origin of differences in CSP rate between An. gambiae and An. arabiensis is discussed in relation to the parity rate, blood feeding frequency, and the hypothesis of genetic factors.

Animals↗

PubMed1997

Crimean-Congo hemorrhagic fever in ticks (Acari: Ixodidae) and ruminants: field observations of an epizootic in Bandia, Senegal (1989-1992).

From 1989 to 1992, a longitudinal study of the relationships between different tick species and domestic ungulates in the transmission and amplification of Crimean-Congo hemorrhagic fever (CCHF) virus was undertaken in the Bandia area in Senegal where the presence of the virus had been reported previously. An epizootic occurred in 1991-1992 and 22 strains of CCHF virus were isolated from Hyalomma marginatum rufipes Koch, Amblyomma variegatum (F.), Rhipicephalus guilhoni Morel & Vassiliades, and R. evertsi evertsi Neumann ticks collected from cattle and goats. No human cases were reported. Transmission of CCHF virus in the area involves a complicated pattern including many tick species and hosts. Amplicons of the S fragment (536 bp) of the CCHF genome of 12 isolates from the study were obtained by polymerase chain reaction and analyzed by restriction-length fragment polymorphism. Three different genotypes of CCHF virus were identified and present during the epizootic. One genotype was recovered from A. variegatum, R. guilhoni, and R. e. evertsi and 2 genotypes were isolated from H. m. rufipes.

Animals↗

PubMed1997

Intervertebral disc prosthesis. Results and prospects for the year 2000.

Presently, the kinematic disc prosthesis model (SB Charité) is the best disc replacement compromise, and is the basis of the evolution of the prosthetic concept at the dawning of the year 2000. Clinical results of a homogeneous series of 105 cases with a mean followup of 51 months show 79% of the patients had an excellent result and 87% returned to work, radiologically, these results correlated with restoration of a well balanced lordosis and with segmental mobility. Factors leading to failure are posterior facet arthritis, osteoporosis, structural deformities, and secondary facet pain. Two- and 3-dimensional numeric modeling enables one to study the total facet joint loading and the maximal local loading on the facet. Dissociation of the stiffness in pure rotation and stiffness in translation of the disc are the bases of the technologic improvement.

Activities of Daily Living↗

PubMed1997

[Cervical teratomas in the child (apropos of 8 cases)].

Eight cases of cervical teratomas in children are reported including 4 boys and 4 girls. Six patients presented within the first 10 days of life. The tumor was congenital in 7 cases. In 3 neonates it produced severe respiratory distress. Neural and chondral tissues were predominant but all three germ layers were represented. All patients were operated upon, with a 2/8 mortality. The main clinical and histopathological features of these rare tumors are reviewed. Early total surgical removal is the cornerstone of treatment.

Airway Obstruction↗

PubMed1997

[Gastric volvulus in the infant. Clinical and radiological diagnosis].

The authors reported two cases of gastric volvulus in female and male babies respectively 5 and 3 months old. Patients presented functional symptoms as vomiting, regurgitation. Baryum meal X ray allows to make diagnosis in meso-axial and organoxial varieties. They showed the interest to evocate this diagnosis related to an infant vomiting's diagnosis and discussed about therapeutic modality.

Female↗

PubMed1996

Biomechanical study of screws in the lateral masses: variables affecting pull-out resistance.

The purpose of this study was to investigate the effects of the design of the screw, the depth of insertion, the vertebral level, and the quality of the host bone on the pull-out resistance of screws used in the lateral masses. The study included twelve fresh cervical spines from human cadavera. Radiographs were made of each specimen to ensure the absence of defects, and then the cancellous-bone density of the vertebral bodies was measured at each level with quantitative computed tomography scanning. Six commercially available screws of various diameters and thread configurations (2.7, 3.2, 3.5, and 4.5-millimeter cortical-bone screws; a 3.5-millimeter cancellous-bone screw; and a 3.5-millimeter self-tapping screw) that are currently used for fixation of the cervical lateral masses were tested for axial load to failure. A twelve-by-twelve Latin square design was used to randomize the screws with regard to level (second through seventh cervical vertebrae), side (right and left), and depth of insertion (unicortical or bicortical purchase). Each screw was then subjected to uniaxial load to failure. The data were analyzed to determine if the diameter of the screw, the thread configuration, the number of cortices engaged, the cervical level, or the bone density was associated with the load to failure. Three major subgroups (greatest, intermediate, and lowest pull-out resistance) were identified. The subgroup with the greatest pull-out resistance included only screws with bicortical purchase; the 3.2, 3.5, and 4.5-millimeter cortical-bone screws and the 3.5-millimeter cancellous-bone screw were in this subgroup. Regardless of the thread configuration, no screw with unicortical purchase was in the group with the greatest pull-out resistance. Two of the three values in the subgroup with the lowest pull-out resistance were for the 3.5-millimeter self-tapping screw (with unicortical or bicortical purchase). The cancellous-bone density of the vertebral body was not associated with pull-out resistance and it did not vary significantly according to the cervical level, with the numbers available. However, the pull-out resistance of the screws varied significantly (p = 0.004) by level: it was the greatest at the fourth cervical level, decreasing cephalad and caudad to that level.

Biomechanical Phenomena↗

PubMed1996

[Cystic form of extralobar pulmonary sequestration. A propos of a case].

Case of bronchogenic cyst associated with extralobar pulmonary sequestration is presented in a 10-month-old baby. At thoracotomy, the tumor was an extralobar pulmonary sequestration with a central cyst surrounded by two pulmonary lobes vascularised by systemic vessels. Resection was easy. The cyst had a respiratory mucosa and was benign. The pathogenesis of the malformation is discussed.

Bronchogenic Cyst↗

PubMed1996

[Phenotypic differences of nosocomial bacterial strains isolated in the obstetric-gynecology service of the University Hospital Center of Dakar].

A study on nosocomial infections was conducted in the Laboratory of Bacteriology-Virology of Aristide Le Dantec's Hospital, in collaboration with the Gynecology Obstetrics clinic located both in the same Dakar's hospital, during May 1995. The aim of the study was to define the phenotypical characteristics of various bacterial strains isolated from the atmosphere health care staff's hands, medical equipment (material, antiseptics) and patients (hospitalized pregnant and newborns in day Nursery). A total of 133 strains were collected and the most frequent isolates were Staphylococcus aureus (27 strains) and Klebsiella pneumoniae (10 strains) encountered mainly in the atmosphere. Otherwise, Escherichia coli (11 strains) and Enterococcus faecalis (11 strains) were more present in hospitalized patients. Results obtained after antimicrobial agents susceptibility (Antibiotics and Heavy metal salts) by Antibiogramm and Minimal inhibitory concentrations (MIC) and also data from biotyping of Klebsiella strains have allowed us to say there's a probable contamination of hospitalized patients by the bacteria from the atmosphere but manuportage too.

Bacterial Infections↗

PubMed1995

[Cinematic in vivo analysis of the knee: a comparative study of 4 types of total knee prostheses].

PURPOSE OF THE STUDY: The goal of the study was to assess in vivo kinematics for four designs of knee prosthesis during level walking, stair climbing and non weight-bearing flexion-extension. PATIENT AND METHODS: 19 patients with unilateral total knee arthroplasty (TKA) were included [5 bicruciate sparing prosthesis (BI), 5 posterior cruciate sparing prosthesis with flat tibial polyethylene (PP), 5 posterior cruciate sparing prosthesis with congruent tibial polyethylene (PC), 4 postero stabilised (PS)]. These 19 patients had no prosthesis nor pathological situation in any other joint of the lower limbs. Each of these 19 prosthesis had an HSS score greater than 80 and no radiographic signs of loosening. Magnitudes of the knee rotations (flexion-extension axial rotation valgus-varus) were evaluated with a 6 degrees freedom of motion electromagnetic-goniometer during level walking, stair climbing and non weight-bearing flexion-extension. The magnitudes of the three rotations were recorded for the 19 prosthetic knees and for the 19 controlateral non prosthetic knees of the patients. Reproducibility of the method was also evaluated on 12 healthy subjects by comparison of magnitudes observed during two different recordings. RESULTS: Reproducibility was excellent for magnitudes of flexion (r = 0.95/p = 0.0001) and axial rotation (r = 0.55/p = 0.002) but less satisfactory for valgus-varus movements (r = 0.46/p = 0.005). The magnitudes of the three rotations were inferior for TKA in comparison with healthy knees for any activities. By comparison of the 19 prosthetic and non prosthetic knees we recorded smaller magnitudes of axial rotation during swing phase for level and stair climbing and during non weight-bearing flexion extension movements. Between the four kind of prosthesis we observed: greater magnitudes of flexion for BI and PC prosthesis during stair climbing (p < 0.05) and greater magnitudes of flexion for BI PC and PS prosthesis during stair descending (p < 0.05). PC prosthesis instead of a congruent polyethylene tibial plateau had greater magnitudes of axial rotation than non constrained BI prosthesis during stair climbing (p = 0.009). In spite of a high femoro-tibial congruency we recorded axial rotation in PS prosthesis during each activities. DISCUSSION AND CONCLUSION: Our method evaluating in vivo knee kinematics was reproducible. These four knee prosthetic designs in spite of a good functional results were unable to reproduce magnitudes of movements recorded in healthy subjects. The small number of prosthesis included in the study prompt us to consider as no definitive the differences observed between the 4 designs. Anyway the influence of design on kinematics should be considered as relative since we recorded axial rotation for all four cruciate substituting prostheses although they had high femoro-tibial congruency. Influence of femoro-tibial congruency and cruciate ligament sparing could be assessed in vivo by means of this reproducible method on a larger population.

Adult↗