[Epidemiological, clinical and etiological profile of tinea capitis in adult patients in Dakar, Senegal]. / Profil épidémio-clinique et étiologique des teignes du cuir chevelu chez l'adulte à Dakar (Sénégal).

OBJECTIVE: To determine the epidemiological and etiological profile of tinea capitis in adults in Dakar (Senegal). PATIENTS AND METHODS: A 9-month prospective, multicenter, descriptive and analytic study. Patients included were aged over 18 years. Mycological tests were used to confirm the diagnosis. RESULTS: 121 patients were included with a mean age of 36.1 years and a hospitalisation frequency of 0.8%. The age range of 64.4% of patients was between19 and 38 years. 51% of patients were housewives. A low socioeconomic level was found in 72.8% of cases. In 3.3% of patients, the disease began in childhood. 31.4% of patients had already consulted a traditional healer. Similar familial cases were noted in 60.3% of patients. Contact with a sheep was noted in 32.2% of cases, deliberate skin lightening in 64% of women, hair salon attendance in 46.7% of women, and immunosuppression in 17.3% of patients, while itching was present in 95.5%. Dermatologic examination showed scaled plaques and a diffuse form, with 92.6% and 64% (n=75) respectively. Wood's light examination was positive in 40.2% of patients. A positive culture test was found in 71%. The most frequently encountered species were: T. soudanense (65%), M. audouinii (21%), T. rubrum (4.7%), M. gypseum (3.5%), T. violaceum (2.3%), T. verrucosum (2.3%) and M. canis (1 case). The clinical course was favorable under treatment with griseofulvin or terbinafine. CONCLUSION: Tinea capitis in adults mainly affects young women. The diffuse form is the most common. The most frequently encountered species was T. soudanense.

Arrêt cardio-respiratoire de l'enfant. Aspects épidémiologiques, thérapeutiques et pronostiques au Sénégal

Introduction : L'Arrêt Cardio-Respiratoire (ACR) est un évènement fréquent dans les services d'urgences et de réanimation pédiatrique. Bien que de nombreuses données soient rapportées dans plusieurs régions du monde, peu sont disponibles en Afrique subsaharienne. L'objectif de cette étude était d'évaluer les aspects épidémiologiques, thérapeutiques et le pronostic des enfants victimes d'ACR au CNHEAR.Patients et méthodes : Il s'agissait d'une étude prospective sur 1 an, concernant les enfants âgés de 0 à 15 ans, ayant présenté un ACR et bénéficié de manœuvres de réanimation au CNHEAR. Les données ont été saisies et analysées avec le logiciel Epi info 3.5.4 et SPSS 24.0. Résultats : Cent-soixante-dix-neuf (179) cas d'ACR ont été enregistrés. Les motifs de consultation les plus fréquents étaient la fièvre et la détresse respiratoire (38,5% chacun). Le délai de consultation moyen était de 3,5 jours. Quarante-neuf virgule sept pour cent (49,7%) avaient consulté dans une structure périphérique avant d'atteindre le niveau central et 13,9% étaient transportés par un transport médicalisé. Les principales circonstances ayant conduit à l'ACR étaient la détresse respiratoire (45,2%), la défaillance hémodynamique (48,7%), et les troubles métaboliques (19,6%). Les pathologies sous- jacentes étaient dominées par le sepsis 20,1%. Au plan thérapeutique, 71,5% avaient eu un massage cardiaque externe. Au décours de la réanimation initiale, le retour à une activité cardio-circulatoire spontanée était de 60,9%. L'évolution secondaire était marquée par la récidive de l'ACR chez 71,6% et finalement le décès de 85,3%. Au final, sur les 179 enfants ayant fait un ACR et bénéficié d'une réanimation, 16 (8,9%) ont survécu et ont été suivis en ambulatoire.Conclusion : La survie après ACR pédiatrique au Sénégal est faible. Des efforts importants restent à faire, notamment une amélioration des ressources matérielles ainsi que des compétences et la formation continue des praticiens en vue d'une meilleure prise en charge des enfants gravement malades

Selective method for identification and quantification of Bifidobacterium animalis subspecies lactis BB-12 (BB-12) from the gastrointestinal tract of healthy volunteers ingesting a combination probiotic of BB-12 and Lactobacillus rhamnosus GG.

AIM: To develop a novel validated method for the isolation of Bifidobacterium animalis ssp. lactis BB-12 (BB-12) from faecal specimens and apply it to studies of BB-12 and Lactobacillus rhamnosus GG (LGG) recovered from the healthy human gastrointestinal (GI) tract. METHODS AND RESULTS: A novel method for isolating and enumerating BB-12 was developed based on its morphologic features of growth on tetracycline-containing agar. The method identified BB-12 correctly from spiked stool close to 100% of the time as validated by PCR confirmation of identity, and resulted in 97-104% recovery of BB-12. The method was then applied in a study of the recovery of BB-12 and LGG from the GI tract of healthy humans consuming ProNutrients® Probiotic powder sachet containing BB-12 and LGG. Viable BB-12 and LGG were recovered from stool after 21 days of probiotic ingestion compared to baseline. In contrast, no organisms were recovered 21 days after baseline in the nonsupplemented control group. CONCLUSIONS: We demonstrated recovery of viable BB-12, using a validated novel method specific for the isolation of BB-12, and LGG from the GI tract of healthy humans who consumed the probiotic supplement. SIGNIFICANCE AND IMPACT OF THE STUDY: This method will enable more detailed and specific studies of BB-12 in probiotic supplements, including when in combination with LGG.

[Leg ulcers in sickle cell disease: A retrospective study of 40 cases]. / Ulcères de jambe au cours de la drépanocytose: étude rétrospective de 40 cas.

BACKGROUND: In Africa, studies primarily devoted to chronic leg ulcer due to sickle cell disease are rare. The objectives of the study were to determine the epidemiology, diagnosis and progression of chronic leg ulcers in sickle cell disease. PATIENTS AND METHODS: A 5-year multicentre, retrospective study was conducted in three university hospitals in Dakar. We included all patients with chronic leg ulcers occurring in a setting of sickle cell disease. RESULTS: We identified 40 cases of chronic leg ulcers associated with sickle cell disease, representing 3.4% of the current population of sickle cell patients in our institutions. The average patient age was 25.9 years and the sex ratio was 2.33. Chronic leg ulcer was the presenting feature enabling diagnosis of sickle cell disease in one third of the cases. The average time to consultation from onset was 5.4 years. Pain was reported in 22 cases (48%). Ulcers were isolated in 76% and multiple in 24% of cases. The most common site was the medial malleolus (39%). A CBC allowed identification of anaemia in 35 cases. Haemoglobin electrophoresis was performed and homozygous sickle cell SS disease was identified in 39 cases and heterozygous SC disease in 1 case. Local treatments included physiologic serum, topical antibiotics and skin grafting. Systemic treatment included supplementation with folic acid in all patients, blood transfusion in 16 cases, vasodilators in 11 cases and antibiotics in 25 cases. The outcome was favourable in 61.8% of cases. DISCUSSION: In Dakar, sickle cell disease is a common cause of chronic leg ulcer and is frequently revealed by chronic leg ulcer.

Negative cutaneous effects of medicinal plants in Senegal.

Use of medicinal plants is common and widespread throughout Africa, including in Senegal. Because efficacy has been demonstrated, public policies have been instituted that have allowed plant-based therapies to have an important role in general primary care. However, little is known about the cutaneous safety of many plant-based therapies. In this 6-month prospective study all cases of dermatitis induced or aggravated by exclusive use of medicinal plants were evaluated via skin allergy testing. The results were classified and compared with the available literature. Forty-three cases of plant-therapy-associated cutaneous reactions were identified, including worsening of existing conditions (56%), recurrence of a previously resolved condition (16%) and new dermatitis arising spontaneously (28%). In the cases where the condition was new, generalized exfoliative dermatitis occurred in 42% of cases with an average time of onset of 9 days. Specific plants were identified in 65% of cases and included 18 varieties. The frequency and severity of plant-induced cutaneous reactions should be the basis for the creation of a phytovigilance programme and re-evaluation of how traditional medicine is used in the general population. When irritation occurs, identification of the responsible plant and allergy testing should be the first steps towards relieving symptoms.

Oral immunostimulation of the oyster Ostrea edulis: Impacts on the parasite Bonamia ostreae.

Bioactive compounds were orally administered to the native European oyster Ostrea edulis to evaluate the immune response and the progression of infection of the protozoan parasite Bonamia ostreae. The immunostimulants lipopolysaccharide and zymosan directly administrated to the water column induced an increase in lysozyme activity and the percentage of granulocytes in naïve oysters over a period of 7 days. In another set of experiments, zymosan and curdlan were microencapsulated in alginate and also administered to the water column to naïve and B. ostreae infected O. edulis. Oyster mortality, prevalence and intensity of infection and several immune parameters were evaluated up to 28 days post-administration. Lysozyme activity, nitric oxide production and the expression of galectin, lysozyme and superoxide dismutase increased after 24 h in both infected and uninfected oysters. Zymosan immunostimulated oysters displayed a decrease in the prevalence of B. ostreae infection not attributed to mortalities but which could be associated to the enhanced ability of immunostimulants to evoke an enhanced immune response in the oysters and reduce infection.

Auditory sensitivity of seals and sea lions in complex listening scenarios.

Standard audiometric data, such as audiograms and critical ratios, are often used to inform marine mammal noise-exposure criteria. However, these measurements are obtained using simple, artificial stimuli-i.e., pure tones and flat-spectrum noise-while natural sounds typically have more complex structure. In this study, detection thresholds for complex signals were measured in (I) quiet and (II) masked conditions for one California sea lion (Zalophus californianus) and one harbor seal (Phoca vitulina). In Experiment I, detection thresholds in quiet conditions were obtained for complex signals designed to isolate three common features of natural sounds: Frequency modulation, amplitude modulation, and harmonic structure. In Experiment II, detection thresholds were obtained for the same complex signals embedded in two types of masking noise: Synthetic flat-spectrum noise and recorded shipping noise. To evaluate how accurately standard hearing data predict detection of complex sounds, the results of Experiments I and II were compared to predictions based on subject audiograms and critical ratios combined with a basic hearing model. Both subjects exhibited greater-than-predicted sensitivity to harmonic signals in quiet and masked conditions, as well as to frequency-modulated signals in masked conditions. These differences indicate that the complex features of naturally occurring sounds enhance detectability relative to simple stimuli.

Auditory detection of ultrasonic coded transmitters by seals and sea lions.

Ultrasonic coded transmitters (UCTs) are high-frequency acoustic tags that are often used to conduct survivorship studies of vulnerable fish species. Recent observations of differential mortality in tag control studies suggest that fish instrumented with UCTs may be selectively targeted by marine mammal predators, thereby skewing valuable survivorship data. In order to better understand the ability of pinnipeds to detect UCT outputs, behavioral high-frequency hearing thresholds were obtained from a trained harbor seal (Phoca vitulina) and a trained California sea lion (Zalophus californianus). Thresholds were measured for extended (500 ms) and brief (10 ms) 69 kHz narrowband stimuli, as well as for a stimulus recorded directly from a Vemco V16-3H UCT, which consisted of eight 10 ms, 69 kHz pure-tone pulses. Detection thresholds for the harbor seal were as expected based on existing audiometric data for this species, while the California sea lion was much more sensitive than predicted. Given measured detection thresholds of 113 dB re 1 µPa and 124 dB re 1 µPa, respectively, both species are likely able to detect acoustic outputs of the Vemco V16-3H under water from distances exceeding 200 m in typical natural conditions, suggesting that these species are capable of using UCTs to detect free-ranging fish.

The fusion of unattended duration representations as indexed by the mismatch negativity (MMN).

Within a single train of same-duration (standard) stimuli, an occasional longer-duration (deviant) sound elicits mismatch negativity (MMN) with a peak latency (measured relative to sound onset) reflecting the standard duration representation. When two such trains are presented in a dichotic paradigm, a separate duration representation arises for each train. We examined the role of attention in this segregation. Four sound trains of differing frequencies (1000 and 1200 Hz to one ear, 2000 and 2400 Hz to the other ear) were presented simultaneously. Participants attended the lower frequency (Low) sounds (always 100 ms) in one ear. Duration of the other (High) sounds varied: 100 ms in the Equal condition; 40 ms in the Short condition. If attention was necessary for separation of sound representations, the two attended ear representations were hypothesised to segregate whilst the two unattended ear's representations would remain fused. Duration MMN was recorded to occasional (1 in 18) 150 ms deviants in all trains. In the Short condition, if unattended ear representations fused, earlier peaking unattended Low sound MMN was expected, relative to when this ear was attended. In the same condition, the MMN for unattended High sounds was expected to peak later, relative to when attended. Low sound unattended MMN latency was indeed earlier by ~30 ms relative to when attended. High sound unattended MMN latency, however, only increased ~9 ms in the same transition. This smaller magnitude change is explained by a minimum MMN onset latency. Attention alone appears to offer a basis for segregating MMN representations.

[Food habits and oral hygiene of students. Investigation of 150 students in university housing]. / Habitudes alimentaires et d'hygiène orale des étudiants. Enquête auprès de 150 étudiants en résidence universitaire.

The objective of this study is to describe the food intake and the oral hygiene habits of 150 Senegalese students living in a university campus. According to Miller, we realised a four days survey. We noted an increase of sugar drinks; tea is the most consumed drink. The results showed also that the toothbrush as means of oral hygiene supplanted the traditional means such as "cure dents" or water rinse with finger.

Role of Hpn and NixA of Helicobacter pylori in susceptibility and resistance to bismuth and other metal ions.

BACKGROUND: Helicobacter pylori produces Hpn, a 60-amino acid, histidine-rich protein that avidly binds nickel and zinc ions, and NixA, a high-affinity nickel transporter in the cytoplasmic membrane. We tested the hypothesis that Hpn and NixA govern susceptibility to metal ions in H. pylori. MATERIALS AND METHODS: Hpn-negative mutants of four H. pylori strains were constructed by standard allelic exchange techniques to yield isogenic Hpn+/Hpn-deficient pairs. A metal concentration that inhibited growth by 50% (IC50) was calculated for Ni2+, Zn2+, Cu2+, and Co2+ by comparing OD600 of cultures in metal-supplemented and control media. RESULTS: Among all four pairs of isogenic strains, the tolerance for Ni2+ was reduced significantly (p <.001) in the Hpn mutants; the mean IC50 value for wild-type strains was 1.9 mM; for the mutant, it was 0.8 mM. In contrast, growth inhibition by Zn2+ was identical within the fours pairs, as was Cu2+ and Co2+ tolerance in one pair tested. We also found that deletion of the hpn gene increases susceptibility to therapeutic forms of bismuth by testing a mutant and wild-type pair with ranitidine bismuth citrate, bismuth citrate, and four antibiotics. Minimal inhibitory concentrations of ranitidine bismuth citrate dropped from 9.2 to 2.3 microg/ml, and those of bismuth citrate dropped from 7.4 to 3.2 microg/ml (p <.05 for both comparisons), while susceptibility to the antibiotics was unaffected. Disruption of the nixA gene encoding the specific Ni2+ transport protein of H. pylori did not change susceptibility to bismuth. CONCLUSION: We concluded that bacteria lacking Hpn, cultured in vitro, are more susceptible than is the wild type to bismuth and Ni2+.

Traditional tea drinking in Senegal. A real source of fluoride intake for the population.

Tea drinking after meals is a traditional practice in Senegal where more than 80% of the population from 15 to 60 years old drink tea. According to the tradition, in one session, each tea consumer has to drink 3 cups of decocted tea. The content of a cup is about 30 ml of liquid. Some people drink tea three times daily, that is to say after each meal. Tea plant is rich in fluoride. To determine the effective intake of the Senegalese population from this source, we measured the fluoride concentration not only for each component of the prepared tea but also for each cup of prepared tea. For this study, we used the two main kinds of tea existing locally. The analyses have been done at Rochester, NY Eastman Dental Center, Oral Biology Dept Fluoride Laboratory using the Taves Microdiffusion Method and the fluoride Ion Specific Electrode. The results so that the mean total fluoride concentration of each cup, from the first to the third one, is: 4.0 mg F-/L, 7.436 mg F-/L and 1.230 mg F-/L. It means that on an average in one session, a Senegalese tea consumer has a daily fluoride intake of 1.139 mg F-/L when taking in count the total fluoride and drinking only 90 ml of tea. If we consider the ionic fluoride the amount of daily ingested fluoride for someone who takes only 3 tea-pots of 30 ml each, is 0.830 mg. To conclude, we state that this traditional practice may have a caries preventive effect. Further studies will be grateful for that practice when setting up a caries preventive program in our country. We will also be careful in extending that practice to children less than 8 years old because it might cause dental fluorosis as in Senegal the optimal dose of fluoride is 0.8 mg F-/L.

Unique susceptibility of Helicobacter pylori to simethicone emulsifiers in alimentary therapeutic agents.

Helicobacter pylori is killed in vitro by polyoxyethylene acyl esters and ethers similar to simethicone emulsifiers in therapeutic antifoams. The MBC of these compounds for Helicobacter pylori was less than 20 micrograms/ml, while other gram-negative bacteria were unaffected by much higher concentrations of up to 50 mg/ml.

Natural occurrence of ochratoxin A in food and feed in Senegal.

A retrospective study covering 1984-88 showed that urogenital diseases were the third most frequent cause of death in Senegal. The purpose of our study was to see whether ochratoxin A is involved in the etiology of these nephropathies. A total of 166 samples of eight principal types of food and feed consumed in this country were obtained randomly at markets in Dakar and Kaolack and analysed for ochratoxin A using the method of analysis of the Association of Official Analytical Chemists. Only cowpea (Vigna unguiculata), from a legume widely distributed in Senegal, was contaminated (16% of samples), at an average level of 34 micrograms/kg. All other samples were free of ochratoxin A, indicating that it is not directly correlated with the renal diseases observed. Aflatoxin B1 was detected in almost all of the samples, and a competition between moulds producing the two toxins is suggested.