Search PubMed⌕ Search

Biomedical subjects

A Mahé

Publications and source records attributed to A Mahé.

At least 19 recordsLinked to original sources
PubMed2005

Definition of an algorithm for the management of common skin diseases at primary health care level in sub-Saharan Africa.

In order to help primary health care (PHC) workers in developing countries in the care of common skin diseases, an algorithm for the management of pyoderma, scabies, superficial mycoses, contact dermatitis and referral of early leprosy cases (based on the identification of diseases through the presence of objective key signs, and on treatments by generic drugs) was elaborated. One thousand patients were seen by trained dermatologists, who established diagnoses and treatments; in addition, there was systematic recording of each key sign, according to the successive algorithm steps. We compared the diagnostics and treatments obtained for several combinations of diagnostic signs, with those of the dermatologists. Sensitivity, specificity, positive predictive value and negative predictive value of defined combinations were high for pyoderma, scabies and superficial mycoses. Values were less exact for dermatitis and leprosy, but were considered sufficient for the level of health care targeted. The apportionment of treatments between the algorithm and the dermatological approaches was considered appropriate in more than 80% of cases; mismanagement was possible in 7% of cases, with few predictable harmful consequences. The algorithm was found satisfactory for the management of the dermatological priorities according to the standards required at the PHC level.

Adolescent↗
PubMed2005

High prevalence of non-leprotic hypochromic patches among children in a rural area of Mali, West Africa.

The identification of one or several hypochromic patches (HP) on the skin is a key stage in the diagnosis of leprosy on dark skin. However, HP are often caused by other disorder than leprosy. A study to determine the prevalence and causes of HP among children was carried out in a rural area of Mali in November 2001. All children under 15 years of age in two villages in an endemic area were screened by two dermatologists. Among the 1729 children seen, HP were identified in 71 patients, with a prevalence of 4.1%. The most common cause of HP was tinea versicolor, which was present in 39.4% of children with HP, followed by pityriasis alba in 31%, naevus achromicus in 24% and vitiligo in 5.6%. No case of leprosy was detected. Our study raises several points with practical consequences for the detection of leprosy cases: the high prevalence of non-leprous HP compared to leprosy, the reliability of the clinical diagnosis of leprosy, and the role of general health care workers in the detection of leprosy cases. Helping those who should be involved in that detection in distinguishing true cases from other hypochromic disorders appears to be a priority.

Age Distribution↗
PubMed2004

Human T-cell leukaemia/lymphoma virus type 1-associated infective dermatitis in Africa: a report of five cases from Senegal.

BACKGROUND: Infective dermatitis (ID) is a rare dermatological condition of childhood that has been linked to human T-cell leukaemia/lymphoma virus type 1 (HTLV-1). Most cases have been reported in the Caribbean. Although several million people are estimated to be infected by HTLV-1 in sub-Saharan Africa, no case of ID has been reported in this area. OBJECTIVES: To identify and to describe cases of HTLV-1-associated ID in Senegal, West Africa. METHODS: Over a 3-year period, a serological test for HTLV-1 was performed at a dermatological centre in Dakar, Senegal, in children who presented with a picture suggestive of ID. Complementary haematological, immunological and virological investigations were performed in infected children and in their mothers. RESULTS: Five patients with typical HTLV-1-associated ID were identified, of ages 17, 5, 4, 3 and 3 years; two patients belonged to the same family. They all presented with repeated flares of superinfected dermatitis involving typical sites of ID (mainly the scalp, external ears, nares and eyelids), associated with nasal discharge, and less commonly with a nonspecific papular rash on the face or trunk. Although oral antibiotic therapy always gave effective control of the symptoms, recurrences were constant. A persisting dry dermatitis of the retroauricular folds was common between flares. Infection in the oldest patient was associated with a chronic adult T-cell leukaemia/lymphoma. The mothers of three patients, and the grandmother of another, were all infected by HTLV-1 strains belonging to the Cosmopolitan molecular subtype, with a perfect nucleotide identity of long-terminal repeat and env gp21 genomic regions within each family. CONCLUSIONS: We present the clinical and virological features of the first reported African cases of HTLV-1-associated ID. When compared with data from the Caribbean, infectious features seemed particularly prominent. ID appears to be overlooked in sub-Saharan Africa, where it might be easily confused with common pyoderma. Breast feeding appears to be the origin of HTLV-1 contamination of the children.

Adolescent↗
PubMed2003

Skin diseases associated with the cosmetic use of bleaching products in women from Dakar, Senegal.

BACKGROUND: The cosmetic use of bleaching products is considered a common practice in dark-skinned women from sub-Saharan Africa. However, there are few studies on this subject. OBJECTIVES: To increase the knowledge about the dermatological consequences of this practice in Dakar, the capital of Senegal. METHODS: A representative sample of 368 adult women presenting at our dermatological centre was selected. Each woman was questioned about her cosmetic use of bleaching products. Next, the following data were recorded in 425 women who used bleaching products: names and types of products used; modalities of the skin bleaching practice; skin diseases motivating the dermatological visit, with recording of their clinical features; and results of a full skin examination. The active substances of the bleaching products were determined mainly by reading the indications on their packages; with products of unknown composition, a pharmacological analysis of samples was done. A statistical analysis was performed. RESULTS: Of the 368 women questioned, 194 (52.7%) were current users of bleaching products. Concerning the 425 users enrolled, products were applied on the whole body in 92% of users, with a median duration of use of 4 years. The active principles used included hydroquinone (used by 89% of users), glucocorticoids (70%), mercury iodide (10%) and caustic agents (17%); 13% of users used products of unknown composition. In the samples that were analysed, hydroquinone was found at concentrations of between 4% and 8.7%. Concerning steroids, superpotent (class 1) glucocorticoids predominated. The main skin complaints in bleaching products users included dermatophyte infections (n = 105) and scabies (n = 69), both often unusually extensive and severe; acne (n = 42), often severe; eczema (n = 41); irritant dermatitis (n = 14); and dyschromia (n = 26, including 14 cases of exogenous ochronosis). The skin examination noted features apparently disregarded by users: striae (noticed in 39% of users), and macular hyperchromia involving the face, mainly the periocular area (33%). The statistical analysis showed that glucocorticoid use was associated with the presence and severity of infectious skin diseases, and of acne. CONCLUSIONS: More than half of the adult women presenting at our dermatology centre were using bleaching products. Most skin diseases observed in bleaching products users appeared to be induced, aggravated or modified by this practice. Superpotent topical glucocorticoids appeared to be the main agents responsible for the observed complications. The cosmetic use of bleaching products therefore has a major impact on our current dermatological practice.

Acne Vulgaris↗
PubMed2003

[Béjel].

Explore the source record for details and available documents.

Child↗
PubMed2003

[Public health and dermatology in developing countries].

Recently some common skin diseases (SD) (i.e. pyoderma, scabies, and superficial mycosis) received special interest in terms of public health assessing their significance in developing countries (DC). The importance of this problem has been established through several kinds of studies: studies from specialized dermatology centres, where the main reasons for consulting were common infectious skin diseases; prevalence studies in the general population pointing out very high prevalence rates for common infectious SD; and studies conducted in non-specialized health centres, where those SD represented about 10% of the total number of consultations. Classical complications of common infectious SD, such as post-streptococcic nephritis, appear rather unusual. However, the costs related to SD have been established as significant; this is partly due to the low efficiency of the health agents when trying to manage SD, and to their usual lack of training. So far, SD have been considered as having a very low priority level, due to their low lethality rate, and therefore have been ignored by health authorities. However, it seems unwise to ignore a health problem for which such a demand of the populations is expressed. Health policies aiming at the improvement of this situation have to be aware of the economic and health system context in DC, and should take into account every step of the health system. The following actions have been proposed: definition of SD priorities; training of non-specialized health agents to a basic management of SD priorities; promotion of use and availability of low-cost "essential dermatologic drugs"; education of the populations regarding measures to prevent certain SD. The feasibility and the impact of such a "public health dermatology" program remain to be evaluated.

Developing Countries↗
PubMed2003

[Principles for the control of sexually transmitted infections in tropical areas].

Owing to their frequency and their own complications, sexually transmitted infections (STI) constitute a very classical health problem, especially in developing areas. The interest for those diseases has been on the rise since the beginning of the AIDS pandemic. Conventional sexually transmitted diseases (such as syphilis, chancroid, infections due to Neisseria gonorrhoeae and to Chlamydia trachomatis) are potent cofactors of HIV transmission. It has been established that the treatment of patients with STI was able to lower the HIV incidence at the community level. Today the fight against STI relies mainly on preventive measures (promotion of lower risk sexual behaviours, blood transfusion safety), and on medical management of patients with STI. In order to treat rapidly cheaply and efficiently a great number of patients, standardised syndromic approaches, using generic drugs, have been elaborated for the most common STI. Other important complementary measures are based on the treatment of sexual partners and on the promotion of condom use. In addition to prevention of their specific complications, the fight against STI has become a major component of health policies against AIDS in developing countries.

Humans↗
PubMed2003

[Cosmetic use of skin depigmentation products in Africa].

The use of skin lightening products represents a real social phenomenon in many Sub-Saharan African countries. A few studies have been published on this subjects. An important proportion of the adult female population, estimated between 25 and 67% uses regularly and daily these creams. Today the products used are mainly dermocorticosteroids and hydroquinone. Their use over a long period of time is responsible for many cutaneous side effects mainly acne, pigmentary disorders, stretch marks and cutaneous infections. Systemic side effects have recently been reported, mainly related to the use of corticosteroids. The necessary control of the products by the local health authorities remains difficult.

Adrenal Cortex Hormones↗
PubMed2002

[Dry skin and black skin: what are the facts?].

We present a review of the data in the literature on the potential specificities of the stratum corneum of so-called "black" skin, together with the afferent cutaneous hydration regulation process. The methodology of the studies is often debatable, not only for basic (absence of definition of "black skin") but also for technical reasons. Their results are often contradicting. Other than certain subtle differences, related to potentially enhanced preservation of the epidermis of dark skin from heliodermal xerosis, we conclude in the similarity of the physicochemical characteristics of the stratum corneum in the different color of skin. Moreover, the data available do not suggest a predisposition of certain skin colors to the occurrence of pathological states involving the stratum corneum. However, dark skin is characterized by its semiologic capacity of taking on a "ashy" aspect related to a better assessment of normal or xerotic stratum corneum because of melanic pigmentation.

Black People↗
PubMed2001

Bacterial skin infections in a tropical environment.

The subject of bacterial skin infection in the tropics has shown some significant advances in the past few years, although it is still relatively understudied. Of special interest is the emerging concern about the public health aspects of pyoderma, either primary or secondary to scabies, in developing countries. In addition, certain more unusual agents, such as Bacillus anthracis and Corynebacterium diphtheriae, continue to cause significant problems in some areas, while incidence of other tropical diseases, such as endemic treponematoses, has largely dropped.

Bacillus anthracis↗
PubMed2000

Characterization of two members of the maize gene family, Incw3 and Incw4, encoding cell-wall invertases.

Two maize putative cell-wall invertase genes (Incw3 and Incw4) have been isolated by screening a genomic DNA library (Zea mays L. W22) using the cDNA probes encoding the two maize cell-wall invertases Incw1 and Incw2. The Incw3 and Incw4 genes contain six exons/five introns and five exons/four introns, respectively. The protein sequences deduced from both genes revealed a beta-fructosidase motif and a cysteine catalytic site known to be conserved in invertase genes. A detailed analysis of the protein and nucleotide sequences provides evidence that the Incw3 and the Incw4 genes encode putative cell-wall invertases. Furthermore, the isoelectric point deduced from the INCW4 protein sequence suggested that the Incw4 gene may encode a unique type of cell-wall invertase unbound in the apoplast. Gene expression studies using RT-PCR and in-situ RT-PCR hybridization showed that the Incw3 expression is organ/tissue-specific and developmentally regulated. In contrast, the Incw4 gene is constitutively expressed in all vegetative and reproductive tissues tested.

Amino Acid Sequence↗
PubMed2000

Evidence against a direct cytotoxic effect of alpha interferon and zidovudine in HTLV-I associated adult T cell leukemia/lymphoma.

The combination of the anti-viral agents, zidovudine (AZT) and interferon-alpha (IFN), is a potent treatment of HTLV-I-associated adult T cell leukemia/lymphoma (ATL). In this study we investigate the possible mechanism of action of this combination by examining several cellular parameters including cell proliferation, cell cycle distribution and apoptosis. The ATL-derived T cell lines HuT-102 and MT-2 served as models. HTLV-I negative T cell lines (CEM and Jurkat) were used as controls. No significant modification of cell growth was observed except at suprapharmacological doses of AZT and IFN. Moreover, these effects were less pronounced in HTLV-I-infected cell lines compared to control cell lines. AZT and IFN treatment did not induce any significant modification of the expression of bcl-2 and p53. Interestingly no in vitro cytotoxic effect of AZT/IFN combination was observed on fresh leukemic cells derived from an acute ATL patient at diagnosis despite achievement of in vivo complete remission using the same therapy. These results suggest that the therapeutic effect of AZT and IFN is not through a direct cytotoxic effect of these drugs on the leukemic cells.

Aged↗
PubMed2000

A maize vacuolar invertase, IVR2, is induced by water stress. Organ/tissue specificity and diurnal modulation of expression.

The expression of invertases was analyzed in vegetative organs of well-watered and water-stressed maize (Zea mays) plants. Early changes in sucrose metabolism and in acid soluble invertase expression were observed in vegetative sink and source organs under mild water stress. The organ-specific induction of acid invertase activity was correlated with an increase in the Ivr2 gene transcripts and in the vacuolar invertase proteins. In addition diurnal changes in activity and Ivr2 transcripts for vacuolar invertase were noted in shoots. Hexoses (glucose and fructose) accumulated in all organs examined from water-stressed plants. In situ localization studies showed that glucose accumulation, vacuolar invertase activity, invertase protein, and the Ivr2 transcripts colocalized specifically in bundle sheath and vascular tissue cells of mature stressed leaf; in primary roots the stress-induced increase of Ivr2 transcripts was detected only in root tips. Based on these results different regulatory roles are proposed in sink and source organs for the stress induced Ivr2 vacuolar invertase.

Blotting, Northern↗