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Recent evidence suggests the existence of a miRNA regulatory network involving human telomerase reverse transcriptase gene (hTERT), with miR-138-5p playing a central role in many types of cancers. However, little is known about the regulation of hTERT expression by microRNA (miRNAs) in melanocytic tumors. Here, we investigated the effects of miR-138-5p in hTERT regulation in melanoma cells lines. In vitro studies demonstrated higher miR-138-5p and lower hTERT messenger RNA (mRNA) expression in human epidermal melanocytes, compared with melanoma cell lines (A2058, A375, SK-MEL-28) by quantitative polymerase chain reaction (qPCR) observing a negative correlation between them. A2058 melanoma cells were selected to be transfected with miR-138-5p mimic or inhibitor. Using luciferase assay, hTERT was identified as a direct target of this miRNA. Overexpression of miR-138-5p detected by Western blot revealed a decrease in hTERT protein expression (p = 0.012), and qPCR showed a reduction in telomerase activity (p < 0.001). Moreover, suppressions in cell growth (p = 0.035) and migration abilities (p = 0.015) were observed in A2058-transfected cells using thiazolyl blue tetrazolium bromide and flow cytometry, respectively. This study identifies miR-138-5p as a crucial tumor suppressor miRNA involved in telomerase regulation. Targeting it as a combination therapy with immunotherapy or targeted therapies could be used in advanced melanoma treatment; however, more preclinical studies are necessary.

Several studies have focused on identifying microRNAs involved in the pathogenesis of melanoma. However, its association with clinicopathological features has been scarcely addressed. The aim of this study is to identify microRNAs expression profiles related to aggressive clinicopathological and molecular features, and to analyze the association with melanoma survival. A retrospective and observational study was performed in a series of 179 formalin-fixed paraffin embedded primary cutaneous melanomas. First, a screening analysis on a discovery set (n = 22) using miRNA gene chip array (Affymetrix, Santa Clara, California, USA) was performed. Differentially expressed microRNAs were detected employing the software Partek Genomic Suite. Validation of four microRNAs was subsequently performed in the entire series (n = 179) by quantitative real time PCR (qRT-PCR). MicroRNAs expression screening analysis identified 101 microRNAs differentially expressed according to Breslow thickness (=1 mm vs. >1 mm), 79 according to the presence or absence of ulceration, 78 according to mitosis/mm2 (

Several studies have focused on identifying microRNAs involved in the pathogenesis of melanoma. However, its association with clinicopathological features has been scarcely addressed. The aim of this study is to identify microRNAs expression profiles related to aggressive clinicopathological and molecular features, and to analyze the association with melanoma survival. A retrospective and observational study was performed in a series of 179 formalin-fixed paraffin embedded primary cutaneous melanomas. First, a screening analysis on a discovery set (n = 22) using miRNA gene chip array (Affymetrix, Santa Clara, California, USA) was performed. Differentially expressed microRNAs were detected employing the software Partek Genomic Suite. Validation of four microRNAs was subsequently performed in the entire series (n = 179) by quantitative real time PCR (qRT-PCR). MicroRNAs expression screening analysis identified 101 microRNAs differentially expressed according to Breslow thickness (1 mm), 79 according to the presence or absence of ulceration, 78 according to mitosis/mm(2) (= 1 mitosis) and 97 according to the TERT promoter status (wt vs. mutated). Six microRNAs (miR-138-5p, miR-130b-3p, miR-30b-5p, miR-34a-5p, miR-500a-5p, miR-339-5p) were selected for being validated by qRT-PCR in the discovery set (n = 22). Of those, miR-138-5p, miR-130b-3p, miR-30b-5p, miR-34a-5p were selected for further analysis in the entire series (n = 179). Overexpression of miR-138-5p and miR-130b-3p was significantly associated with greater Breslow thickness, ulceration, and mitosis. TERT mutated melanomas overexpressed miR-138-5p. Kaplan-Meier survival analysis showed poorer survival in melanomas with miR-130b-3p overexpression. Our findings provide support for the existence of a microRNA expression profile in melanomas with aggressive clinicopathological features and poor prognosis.

La trypanosomiase humaine africaine (THA) est l'une des maladies tropicales les plus négligées en Afrique subsaharienne. Avec moins de 1 000 cas déclarés en 2018 et 2019, elle a été ciblée comme maladie pouvant être éliminée d'ici 2030. Des réservoirs cryptiques de Trypanosoma brucei gambiense, tels que les animaux domestiques ou sauvages, apparaissent comme des déterminants pouvant compromettre cet objectif. Mieux comprendre l'impact d'un tel réservoir sur le maintien de la transmission de T. b gambiense nous permettra d'affiner les stratégies de lutte contre la THA. Dans cette revue, nous discutons des différents obstacles (techniques, biologiques, épidémiologiques) auxquels ont été confrontés les chercheurs qui se sont penchés sur cette problématique. Ces obstacles, qui perdurent aujourd'hui, expliquent en partie pourquoi, près d'un siècle après les premières études, l'impact du réservoir animal est toujours un sujet controversé.

Africa contains more human genetic variation than any other continent, but the majority of the population-scale analyses of the African peoples have focused on just two of the four major linguistic groups, the Niger-Congo and Afro-Asiatic, leaving the Nilo-Saharan and Khoisan populations under-represented. In order to assess genetic variation and signatures of selection within a Nilo-Saharan population and between the Nilo-Saharan and Niger-Congo and Afro-Asiatic, we sequenced 50 genomes from the Nilo-Saharan Lugbara population of North-West Uganda and 250 genomes from 6 previously unsequenced Niger-Congo populations. We compared these data to data from a further 16 Eurasian and African populations including the Gumuz, another putative Nilo-Saharan population from Ethiopia. Of the 21 million variants identified in the Nilo-Saharan population, 3.57 million (17%) were not represented in dbSNP and included predicted non-synonymous mutations with possible phenotypic effects. We found greater genetic differentiation between the Nilo-Saharan Lugbara and Gumuz populations than between any two Afro-Asiatic or Niger-Congo populations. F3 tests showed that Gumuz contributed a genetic component to most Niger-Congo B populations whereas Lugabara did not. We scanned the genomes of the Lugbara for evidence of selective sweeps. We found selective sweeps at four loci (SLC24A5, SNX13, TYRP1, and UVRAG) associated with skin pigmentation, three of which already have been reported to be under selection. These selective sweeps point toward adaptations to the intense UV radiation of the Sahel.

Introduction Restaurant food is widely consumed by children and is associated with poor diet quality. Although many restaurants have made voluntary commitments to improve the nutritional quality of children's menus, it is unclear whether this has led to meaningful changes. Methods Nutrients in children's menu items ( n =4,016) from 45 chain restaurants were extracted from the nutrition information database MenuStat. Bootstrapped mixed linear models estimated changes in mean calories, saturated fat, and sodium in children's menu items between 2012 and 2013, 2014, and 2015. Changes in nutrient content of these items over time were compared among restaurants participating in the Kids LiveWell initiative and non-participating restaurants. Types of available children's beverages were also examined. Data were analyzed in 2016. Results There was a significant increase in mean beverage calories from 2012 to 2013 (6, 95% CI=0.8, 10.6) and from 2012 to 2014 (11, 95% CI=3.7, 18.3), but no change between 2012 and 2015, and no differences in nutrient content of other items over time. Restaurants participating in Kids LiveWell reduced entree calories between 2012 and 2013 (−24, 95% CI=−40.4, −7.2) and between 2012 and 2014 (−40, 95% CI=−68.1, −11.4) and increased side dish calories between 2012 and 2015 (49, 95% CI=4.6, 92.7) versus non-participating restaurants. Sugar-sweetened beverages consistently constituted 80% of children's beverages, with soda declining and flavored milks increasing between 2012 and 2015. Conclusions Results suggest little progress toward improving nutrition in children's menu items. Efforts are needed to engage restaurants in offering healthful children's meals.

Background: Tsetse flies are vectors of human and animal African trypanosomiasis. In spite of many decades of chemotherapy and vector control, the disease has not been eradicated. Other methods like the transformation of tsetse fly symbionts to render the fly refractory to trypanosome infection are being evaluated. The aim of the present study was to evaluate the association between trypanosome infections and the presence of symbionts in these tsetse species. Tsetse flies were trapped in two villages of the "Faro and Deo" Division of the Adamawa region of Cameroon. In the field, tsetse fly species were identified and their infection by trypanosomes was checked by microscopy. In the laboratory, DNA was extracted from their midguts and the presence of symbionts (Sodalis glossinidius and Wolbachia sp.) and trypanosomes was checked by PCR. Symbionts/trypanosomes association tests were performed. Results: Three tsetse fly species including Glossina tachinoides (90.1%), Glossina morsitans submorsitans (9.4%) and Glossina fuscipes fuscipes (0.5%) were caught. In all the population we obtained an occurrence rate of 37.2% for Sodalis glossinidius and 67.6% for Wolbachia irrespective to tsetse flies species. S. glossinidius and Wolbachia sp. occurrence rates were respectively 37 and 68% for G. tachinoides and 28.6 and 59.5% for G. m. submorsitans. Between Golde Bourle and Mayo Dagoum significant differences were observed in the prevalence of symbionts. Prevalence of trypanosomes were 34.8% for Glossina tachinoides and 40.5% for Glossina morsitans submorsitans. In G. tachinoides, the trypanosome infection rates were 11, 2.6 and 13.7%, respectively, for T. brucei s.l., T. congolense forest type and T. congolense savannah type. In G. m. submorsitans, these infection rates were 16.7, 9.5 and, 2.4% respectively, for T. brucei s.l., T. congolense forest type and T. congolense savannah type. Conclusions: The rate of tsetse fly infection by trypanosomes was low compared to those obtained in HAT foci of south Cameroon, and this rate was not statistically linked to the rate of symbiont occurrence. This study allowed to show for the first time the presence of Wolbachia sp. in the tsetse fly sub-species Glossina morsitans submorsitans and Glossina tachinoides.

Décrire les caractéristiques épidémiologiques et histo-pathologiques des tumeurs malignes du sein au Cameroun. Il s'agissait d'une étude rétrospective descriptive portant sur les tumeurs malignes du sein, colligées, dans les registres des différents laboratoires d'Anatomie Pathologique publiques et privés repartis dans cinq régions (centre, littoral, Ouest, Nord-ouest, Sud-ouest), pendant une période de 10 ans 2004-2013). Les paramètres étudiés étaient la fréquence, l'âge, le sexe, la localisation, le type et le grade histologique, et les récepteurs hormonaux. Un total de 3044 cas de cancers du sein a été recensé, soit une fréquence annuelle de 304,4 cas en moyenne. Le sexe féminin était le plus représenté avec 2971 cas (97,60%) et les hommes avec 73 cas (2,40%), soit un sexe ratio (H/F) de 0,02. L'âge moyen des patients était de 46±15,87 ans, avec des extrêmes de 13 et 95 ans. Selon la localisation, le sein gauche était atteint dans 1244 cas (52%) et le sein droit dans 1115 cas (47%). Au plan histologique, on retrouvait essentiellement des carcinomes avec 96,50% des cas, des sarcomes 1,39%, des lymphomes 1,07% et la maladie de Paget du mamelon, 1,03%. Les tumeurs épithéliales étaient infiltrantes dans 2049 cas (84,46%), avec une prédominance du carcinome canalaire infiltrant (1870 cas) et non infiltrantes dans 377 cas (15,54%). Le grade histo-pronostic de SBR avait révélé une prédominance du grade II dans 66% des cas. Les cancers du sein restent une pathologie fréquente au Cameroun et atteignent principalement la population féminine en âge de procréer. Ils sont caractérisés par la prédominance du carcinome canalaire infiltrant.

The full impact of a maternal death includes consequences faced by orphaned children. This analysis adds evidence to a literature on the magnitude of the association between a woman's death during or shortly after childbirth, and survival outcomes for her children. The Ifakara and Rufiji Health and Demographic Surveillance Sites in rural Tanzania conduct longitudinal, frequent data collection of key demographic events at the household level. Using a subset of the data from these sites (1996-2012), this survival analysis compared outcomes for children who experienced a maternal death (42 and 365 days definitions) during or near birth to those children whose mothers survived. There were 111 maternal deaths (or 229 late maternal deaths) during the study period, and 46.28 % of the index children also subsequently died (40.73 % of children in the late maternal death group) before their tenth birthday-a much higher prevalence of child mortality than in the population of children whose mothers survived (7.88 %, p value

In order to better understand the diurnal cycle of the Sea-Breeze (SB) in the island of Mallorca, during September 2013 and June 2014 two experimental field campaigns have been conducted in the Campos basin (at the south side). A total of 6 IOPs (clear skies and weak pressure gradient conditions) are analysed using data from the AEMET network and the observations taken close to the coastline (about 900 m inland). They consist on a surface portable station (equipped with an IR camera and a sonic anemometer), a captive balloon (temperature and humidity) and a multicopter (temperature and humidity). Preliminary analysis of the observations show a good agreement between the different sources of data. During the previous phase (0430-0730 UTC) land-breeze conditions were present and after sunrise the sensible heat flux turned to positive meanwhile the turbulence started. In the preparatory phase (0730-0900 UTC) the wind close to the coast started to veer progressively towards the SB direction. As soon as the SB was initiated (0900-1200 UTC), the SB front progressed to the inland direction reaching a mature phase between 1200-1500 UTC. Afterwards, the SB decaying starts and at about 1900 UTC the wind speed was close to zero and the wind veered towards the land to sea direction. During the campaign all phases were measured, except the sounding systems for the mature phase due to the strong wind. Some selected IOPs are further analysed through the use of high-resolution mesoscale simulation. It is found that the model is able to reproduce the observed establishment of the SB although the observed temperature gradients are larger than those observed.

To understand the circulation and the spread of Torpanosoma congolense genotypes in animals of Fontem in the southwest region of Cameroon, T. congolense forest and T. congolense savannah were investigated in 397 domestic animals in eight villages. Out of the 397 domestic animals, 86 (21.7%) were found infected by trypanosomes, using the capillary tube centrifugation test. The PCR with specific primers identified 163 (41.1%) and 81(20.4%) animals infected by T. congolense forest and T. congolense savannah, respectively; showing for the first time the circulation of T. congolense savannah in the Fontem region. No infection with T. congolense savannah was found in pigs whereas goats and sheep were infected by T. congolense forest and/or T. congolense savannah. The prevalence of trypanosomes varied significantly amongst villages and animal species. The genotyping of T. congolense forest positive samples using microsatellites markers showed that multiple genotypes occurred in 27.2% (44/163) of animals sampled, whereas single genotypes were found in 73.8% (119/163) of samples. Some alleles were found in all animal species as well as in all villages and were responsible for major genotypes, whereas others (rare alleles) were identified only in some animals of few villages. These rare alleles were characteristic of specific genotypes, assimilated to minor genotypes which can be spread in the region through tsetse flies. The microsatellite markers show a low genetic variability and an absence of sub-structuration within T. congolense forest. The analysis of the microsatellite data revealed a predominant clonal reproduction within T. congolense forest. Pigs were the animal species with the highest number of different genotypes of T. congolense forest. They seem to play an important epidemiological role in the propagation and spread of different genotypes of T. congolense.

Si quelques études ont été réalisées sur les trypanosomoses chez les animaux domestiques en Afrique Centrale, très peu de recherches ont été consacrées sur ces parasites chez les animaux sauvages. Dans cette étude, la Polymerase Chain Reaction (PCR) a été utilisée pour déterminer les prévalences de différentes espèces de trypanosomes chez les animaux sauvages du foyer de maladie du sommeil de Bipindi. Les résultats préliminaires obtenus montrent que 39% (64/164) d'animaux sauvages du foyer de la maladie du sommeil de Bipindi (Cameroun) ont été en contact avec au moins une espèce de trypanosomes. L'espèce #Trypanosoma brucei$ s.l. a la plus forte prévalence (22%). #Trypanosoma vivax$ a une prévalence relativement importante (11%). La prévalence (6%) du sous-genre #Nannomonas$ (#T. congolense$ "type forest", #T. congolense$ "type savannah" et #T. simiae$) est faible. Les espèces #Trypanosoma simiae$ et #Trypanosoma congolense$ "type forest" ont été trouvées chez les rongeurs et chez les primates uniquement. Le parasite pathogène pour l'homme #T. brucei gambiense$ groupe 1 a une prévalence de 8% (13/164). Les animaux présentant une forte prévalence à #T. brucei gambiense$ sont les rongeurs (#Atherurus africanus$ et #Cricetomys gambianus$), les singes (#Cercopithecus$ et #Cercocebus$) et les ongulés (#Cephalophus$). Nous avons également trouvé deux petits carnassiers (#Genetta servalina$ et #Nandinia binotata$) porteurs de trypanosomes pathogènes pour l'homme. Une confirmation de ces résultats par une étude plus exhaustive permettra de mieux comprendre le phénomène de résurgence de la maladie du sommeil, la pérennisation et la dispersion de l'endémie. (Résumé d'auteur)

Dans le but de montrer l'intérêt de la PCR ("Polymerase Chain Reaction") sur sang dans le diagnostic de la Trypanosomiase Humaine Africaine (T.H.A.), du sang a été collecté dans des tubes EDTA ("Ethylène Diamine Tétra Acétate) chez 1.663 personnes dont 1.614 provenant de 3 foyers actifs de la T.H.A. (Bipindi, Campo et Fontem) au Cameroun et 49 chez des individus (Européens) non exposés à la maladie du sommeil. Les examens parasitologiques et la culture in vitro ont revélé 62 trypanosomés. La PCR a été positive sur 61 trypanosomés et la culture in vitro (KIVI) a apporté 4 malades de plus aux 58 positifs aux examens parasitologiques. Le pourcentage de positivité de l'ensemble des PCR positives parmi les malades, les suspects sérologiques et les témoins négatifs (7% - 117/1.663) est 2 fois celui des examens parasitologiques (3,5% - 58/1.663). Cette technologie peut être utilisée pour détecter les trypanosomes chez les suspects sérologiques lorsque les examens parasitologiques s'avèrent inefficaces. (Résumé d'auteur)