76 research outputs found

    The First International Mini-Symposium on Methionine Restriction and Lifespan

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    It has been 20 years since the Orentreich Foundation for the Advancement of Science, under the leadership Dr. Norman Orentreich, first reported that low methionine (Met) ingestion by rats extends lifespan (Orentreich et al., 1993). Since then, several studies have replicated the effects of dietary methionine restricted (MR) in delaying age-related diseases (Richie et al., 1994; Miller et al., 2005; Ables et al., 2012; Sanchez-Roman and Barja, 2013). We report the abstracts from the First International Mini-Symposium on Methionine Restriction and Lifespan held in Tarrytown, NY, September 2013. The goals were (1) to gather researchers with an interest in MR and lifespan, (2) to exchange knowledge, (3) to generate ideas for future investigations, and (4) to strengthen relationships within this community. The presentations highlighted the importance of research on cysteine, growth hormone (GH), and ATF4 in the paradigm of aging. In addition, the effects of dietary restriction or MR in the kidneys, liver, bones, and the adipose tissue were discussed. The symposium also emphasized the value of other species, e.g., the naked mole rat, Brandt's bat, and Drosophila, in aging research. Overall, the symposium consolidated scientists with similar research interests and provided opportunities to conduct future collaborative studies (Figure 3)

    Differential expression of the brassinosteroid receptor-encoding BRI1 gene in Arabidopsis

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    Abstract Brassinosteroid (BR)-regulated growth and development in Arabidopsis depends on BRASSINOSTEROID INSENSITIVE 1 (BRI1), the BR receptor that is responsible for initiating the events of BR signalling. We analysed the temporal and spatial regulation of BRI1 expression using stable transgenic lines that carried BRI1 promoter:reporter fusions. In both seedlings and mature plants the tissues undergoing elongation or differentiation showed elevated BRI1 gene activity, and it could be demonstrated that in the hypocotyl this was accompanied by accumulation of the BRI1 transcript and its receptor protein product. In seedlings the BRI1 promoter was also found to be under diurnal regulation, determined primarily by light repression and a superimposed circadian control. To determine the functional importance of transcriptional regulation we complemented the severely BR insensitive bri1-101 mutant with a BRI1-luciferase fusion construct that was driven by promoters with contrasting specificities. Whereas the BRI1 promoter-driven transgene fully restored the wild phenotype, expression from the photosynthesisassociated CAB3 and the vasculature-specific SUC2 and ATHB8 promoters resulted in plants with varying morphogenic defects. Our results reveal complex differential regulation of BRI1 expression, and suggest that by influencing the distribution and abundance of the receptor this regulation can enhance or attenuate BR signalling

    Utjecaj toksičnosti metala na reprodukcijsku funkciju u muškaraca

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    A combination of genetic, environmental and lifestyle factors contributes to adverse effects on the reproductive health in men. Metals are pervasive in food, water, air, tobacco smoke, and alcoholic beverages. Experimental studies suggest that many metals have adverse effects on the male reproductive function. However, information about reproductive effects of human exposure to metals is scarce and/or inconsistent. This review summarises the information from epidemiological studies of the effects of metal exposure on reproductive function in men. Factors capable of affecting these relationships were identifi ed and discussed. A particular attention is given to the studies considering influence of concomitant exposure to various metals. These studies have generally confirmed that even moderate- to low-level exposure to lead affects certain reproductive parameters, and that exposure to cadmium affects the prostate function and serum testosterone levels. Adverse effects of mercury, manganese, chromium and arsenic on semen quality and altered serum hormone are less well documented. There is no clear evidence that boron exposure may impair reproductive health in men. Only a few studies have investigated reproductive effects of concomitant exposure to several metals and controlled for potential confounders. Future studies should consider the contribution of combined exposure to various metals and/or other factors that may influence individual susceptibility to reproductive health impairment in men.Postoje indikacije da kombinacija genetskih, okolišnih i čimbenika načina života pridonosi uočenom poremećaju reprodukcijskog zdravlja u muškaraca. Metali su široko rasprostranjeni u čovjekovu okolišu te u hrani, vodi, zraku, cigaretnom dimu i alkoholnim pićima. Rezultati eksperimentalnih istraživanja sugeriraju štetne učinke većine ispitivanih metala na mušku reprodukcijsku funkciju. Međutim, odgovarajuća su istraživanja u ljudi oskudna. Ovaj rad sažima rezultate dosadašnjih epidemioloških istraživanja o učincima izloženosti metalima na mušku reprodukcijsku funkciju. Poseban naglasak dan je istraživanjima koja su razmatrala utjecaj istodobne izloženosti različitim metalima uz čimbenike čovjekova načina života i njihovo međudjelovanje na reprodukcijske učinke. Objavljeni rezultati daju dovoljno dokaza o štetnom djelovanju olova i žive na neke reprodukcijske parametre te kadmija na poremećaj prostate i razinu testosterona u serumu, čak u uvjetima umjerene do niske razine izloženosti. Manje je dokaza o štetnom djelovanju na kvalitetu sjemena i razinu spolnih hormona nađeno za mangan. Podaci koji upućuju na moguće štetno djelovanje arsena ili kroma nisu dosljedni, dok o štetnom djelovanju bora na mušku reprodukcijsku funkciju nema jasnih podataka. Utjecaj potencijalno uzročnih varijabli uzet je u obzir samo u nekoliko radova. Stoga buduća istraživanja poremećaja reprodukcijskog zdravlja u muškaraca trebaju razmatrati doprinos istovremene izloženosti različitim metalima koji u kombinaciji s ostalim čimbenicima mogu utjecati na osobnu (pre)osjetljivost
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