Endocrine and molecular investigations in a cohort of 25 adolescent males with prominent/persistent pubertal gynecomastia

Pubertal gynecomastia is a common condition observed in up to 65% of adolescent males. It is usually idiopathic and tends to regress within 1–2 years. In this descriptive cross-sectional study, we investigated 25 adolescent males with prominent (>B3) and/or persistent (>2 years) pubertal gynecomastia (P/PPG) to determine whether a hormonal/genetic defect might underline this condition. Endocrine investigation revealed the absence of hormonal disturbance for 18 boys (72%). Three patients presented Klinefelter syndrome and three a partial androgen insensitivity syndrome (PAIS) as a result of p.Ala646Asp and p.Ala45Gly mutations of the androgen receptor gene. The last patient showed a 17α-hydroxylase/17,20-lyase deficiency as a result of a compound heterozygous mutation of the CYP17A1 gene leading to p.Pro35Thr(P35T) and p.Arg239Stop(R239X) in the P450c17 protein. Enzymatic activity was analyzed: the mutant protein bearing the premature stop codon R239X showed a complete loss of 17α-hydroxylase and 17,20-lyase activity. The mutant P35T seemed to retain 15–20% of 17α-hydroxylase and about 8–10% of 17,20-lyase activity. This work demonstrates that P/PPG had an endocrine/genetic cause in 28% of our cases. PAIS may be expressed only by isolated gynecomastia as well as by 17α-hydroxylase/17,20-lyase deficiency. Isolated P/PPG is not always a ‘physiological’ condition and should thus be investigated through adequate endocrine and genetic investigations, even though larger studies are needed to better determine the real prevalence of genetic defects in such patients

ENSO Drives interannual variation of forest woody growth across the tropics

Meteorological extreme events such as El Niño events are expected to affect tropical forest net primary production (NPP) and woody growth, but there has been no large-scale empirical validation of this expectation. We collected a large high–temporal resolution dataset (for 1–13 years depending upon location) of more than 172 000 stem growth measurements using dendrometer bands from across 14 regions spanning Amazonia, Africa and Borneo in order to test how much month-to-month variation in stand-level woody growth of adult tree stems (NPPstem) can be explained by seasonal variation and interannual meteorological anomalies. A key finding is that woody growth responds differently to meteorological variation between tropical forests with a dry season (where monthly rainfall is less than 100 mm), and aseasonal wet forests lacking a consistent dry season. In seasonal tropical forests, a high degree of variation in woody growth can be predicted from seasonal variation in temperature, vapour pressure deficit, in addition to anomalies of soil water deficit and shortwave radiation. The variation of aseasonal wet forest woody growth is best predicted by the anomalies of vapour pressure deficit, water deficit and shortwave radiation. In total, we predict the total live woody production of the global tropical forest biome to be 2.16 Pg C yr−1, with an interannual range 1.96–2.26 Pg C yr−1 between 1996–2016, and with the sharpest declines during the strong El Niño events of 1997/8 and 2015/6. There is high geographical variation in hotspots of El Niño–associated impacts, with weak impacts in Africa, and strongly negative impacts in parts of Southeast Asia and extensive regions across central and eastern Amazonia. Overall, there is high correlation (r = −0.75) between the annual anomaly of tropical forest woody growth and the annual mean of the El Niño 3.4 index, driven mainly by strong correlations with anomalies of soil water deficit, vapour pressure deficit and shortwave radiation

Adenocarcinome gastrique a Brazzaville : recherche de la surexpression de l’oncoproteine HER2 par immunohistochimie: Gastric adenocarcinoma in Brazzaville: research for oncoprotein HER2 overexpression by immunohistochemistry

Introduction : la surexpression et/ou l’amplification du gène HER2 est observée dans différentes tumeurs incluant les tumeurs gastriques. Elle est décrite dans 10 à 30% des adénocarcinomes gastriques. Un statut Her2 positif est un facteur de mauvais pronostic et un facteur prédictif de la réponse à une thérapie ciblée, le trastuzumab (herceptinR). Le but de notre étude est de rechercher la surexpression de l’oncoproteine Her2 dans les adénocarcinomes gastriques avancés. Matériels et Méthodes : la recherche de la surexpression de Her2 a été réalisée sur les prélèvements de tissus gastriques carcinomateux (biopsies et pièces opératoires) inclus en paraffine par immunohistochimie. Les échantillons ont été collectés rétrospectivement entre Janvier 2008 et décembre 2018.Résultats : durant cette période, 52 prélèvements ont été analysés. 9,6% des tumeurs surexprimaient Her2. Conclusion : vu le mauvais pronostic de l’adénocarcinome gastrique, la recherche de la surexpression de l'oncoproteine Her2 est devenue indispensable pour sélectionner les patients susceptibles de bénéficier d’une thérapie ciblée anti-HER2. ABSTRACTIntroduction: The over expression of oncoprotein'Her2 has been detected in several cancers and has been particularly studied in breast cancer. It is described in 10 to 30% of gastric adenocarcinomas. A positive Her2 status is a factor of poor prognosis and a predictor of the response to herceptin (trastuzumab). The aim of our study is to investigate the over expression of Her2 oncoprotein in advanced gastric adenocarcinomas while comparing our results with those of the literature. Materials and Methods: The search for over expression of the Her2 oncoprotein is determined on samples of tumor gastric tissues (biopsies and surgical pieces) included in paraffin by the immunohistochemistrytechnique, over a period of 11 years (January 2008- December 2018). Results: During this period, 52 cases of Tumor gastric tissue samples (biopsies and operating pieces) were examined, the rate of cases over expressing the Her2 oncoprotein in our study is 9.6%, this over expression remains within the limit of most series of literature including a large study called ToGA.Conclusion: Given the poor prognosis for gastric adenocarcinoma, the search for over expression of the Her2 oncoprotein has become essential in order to select the patients likely to benefit from treatment with Herceptin

Forest biomass, productivity and carbon cycling along a rainfall gradient in West Africa

Net Primary Productivity (NPP) is one of the most important parameters in describing the functioning of any ecosystem and yet it arguably remains a poorly quantified and understood component of carbon cycling in tropical forests, especially outside of the Americas. We provide the first comprehensive analysis of NPP and its carbon allocation to woody, canopy and root growth components at contrasting lowland West African forests spanning a rainfall gradient. Using a standardized methodology to study evergreen (EF), semi-deciduous (SDF), dry forests (DF) and woody savanna (WS), we find that (i) climate is more closely related with above and belowground C stocks than with NPP (ii) total NPP is highest in the SDF site, then the EF followed by the DF and WS and that (iii) different forest types have distinct carbon allocation patterns whereby SDF allocate in excess of 50% to canopy production and the DF and WS sites allocate 40%-50% to woody production. Furthermore, we find that (iv) compared with canopy and root growth rates the woody growth rate of these forests is a poor proxy for their overall productivity and that (v) residence time is the primary driver in the productivity-allocation-turnover chain for the observed spatial differences in woody, leaf and root biomass across the rainfall gradient. Through a systematic assessment of forest productivity we demonstrate the importance of directly measuring the main components of above and belowground NPP and encourage the establishment of more permanent carbon intensive monitoring plots across the tropics