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61.

Lactobacillus salivarius A3iob was administered to productive colonies belonging to commercial apiaries of small beekeepers (around 30–50 hives each one), from four departments of the province of Jujuy (Argentina): Yala, Tilquiza, El Carmen, and Los Alisos. The incidence of Varroa destructor and Nosema spp., before and after winter, was monitored during 2 years of study (2014–2015). Depending on the geographical location of each apiary and the application time, a monthly dose of the bacteria (105 CFU/mL) reduced the levels of varroasis between 50 and 80%. Interestingly, L. salivarius A3iob cells remitted the percentage of the mites to undetectable values in an apiary treated with flumethrin (at Yala, Yungas region).

On the other hand, the spore levels of Nosema spp. in the lactobacilli-treated colonies also depended on the apiary and the year of application, but a significant decrease was mainly observed in the post-winter period. However, at Rivera (El Carmen’s department), no significant changes were detected in both parameters.

These results obtained after 2 years of work suggest that delivering L. salivarius A3iob cells to the bee colonies can become a new eco-friendly tool to cooperate with the control of these bees’ pests.

  相似文献   
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In many moth species regulation of pheromone production has been attributed to the timely release of a pheromone biosynthesis activating neuropeptide (PBAN). The gene encoding PBAN has been sequenced in two moth species. Immunochemical studies as well asin situ hybridization and Northern analysis of PBAN encoding mRNA have localized the neuroendocrine cells responsible for the production of PBAN and have traced the neuronal network of PBAN immunoreactivity. Release into the bloodstream has been demonstrated, the target tissue delineated, and the signal transduction pathway and its modulation analyzed. This paper reviews the current status of research concerning the neuroendocrine control of pheromone production in Lepidopterans and presents some recent developments concerning the receptors involved in the pheromonotropic activity. In this study, we report on the use of a biologically active photoaffinity-biotin-labeled derivative of PBAN N-[N-(4-azido-tetrafluorobenzoyl-biocytinyloxyl-succinimide) and show the presence of a protein (estimated molecular weight of 50 kDa) which specifically binds to PBAN in membrane preparations of pheromone glands. Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No.2279-E, 1997 series  相似文献   
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To assess presence of virus DNA in skin lesions, swab samples from 82 squamous cell carcinomas of the skin (SCCs), 60 actinic keratoses (AKs), paraffin-embedded biopsies from 28 SCCs and 72 kerathoacanthomas (KAs) and fresh-frozen biopsies from 92 KAs, 85 SCCs and 92 AKs were analyzed by high throughput sequencing (HTS) using 454 or Ion Torrent technology. We found total of 4,284 viral reads, out of which 4,168 were Human Papillomavirus (HPV)-related, belonging to 15 known (HPV8, HPV12, HPV20, HPV36, HPV38, HPV45, HPV57, HPV59, HPV104, HPV105, HPV107, HPV109, HPV124, HPV138, HPV147), four previously described putative (HPV 915 F 06 007 FD1, FA73, FA101, SE42) and two putatively new HPV types (SE46, SE47). SE42 was cloned, sequenced, designated as HPV155 and found to have 76% similarity to the most closely related known HPV type. In conclusion, an unbiased approach for viral DNA detection in skin tumors has found that, although some new putative HPVs were found, known HPV types constituted most of the viral DNA.  相似文献   
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Mouse Cdx genes are involved in axial patterning and partial Cdx mutants exhibit posterior embryonic defects. We found that mouse embryos in which all three Cdx genes are inactivated fail to generate any axial tissue beyond the cephalic and occipital primordia. Anterior axial tissues are laid down and well patterned in Cdx null embryos, and a 3' Hox gene is initially transcribed and expressed in the hindbrain normally. Axial elongation stops abruptly at the post-occipital level in the absence of Cdx, as the posterior growth zone loses its progenitor activity. Exogenous Fgf8 rescues the posterior truncation of Cdx mutants, and the spectrum of defects of Cdx null embryos matches that resulting from loss of posterior Fgfr1 signaling. Our data argue for a main function of Cdx in enforcing trunk emergence beyond the Cdx-independent cephalo-occipital region, and for a downstream role of Fgfr1 signaling in this function. Cdx requirement for the post-head section of the axis is ancestral as it takes place in arthropods as well.  相似文献   
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IntroductionIodine is considered to be an essential micronutrient in pregnant women. Iodine placental transport to the embryo-fetus is essential for hormone synthesis and is crucial for nervous system development. However, the relationship between iodine intake and placental weight and its potential implications for the newborn have not been studied.Material and methodsIodine intake was analyzed in 77 pregnant women based on urinary iodine excretion (UIE) levels, measured using Pinós modified method (normal value, ≥ 150 μg/L). Placental weight was measured (PW: normal, ≥500 g). In the newborn, weight, height, and head perimeter (HP) were also measured. Placental index (PI: placental weight/newborn weight) was calculated, and was considered normal if ≥0.15.ResultsUIE was normal in 50 pregnant women (mean ± SD, 279 μg/L ± 70.22 μg/L) and decreased in 27 (94 μg/L ± 31.49 μg/L). Newborns of mothers with low UIE had a similar weight (3357 g ± 416.30 g; n: 27) to those of mothers with normal UIE (3489 g ± 560.59 g; n: 50). Forty-four percent of mothers with low UIE had PW <500 g, and statistically lower HPs were found in newborns of mothers with low PW (PW3500 g: 36.05 cm ± 0.55 cm, n: 54; PW <500 g: 33.93 cm ± 15 cm, n:23, p < 0.019). Similar results were found with PI, but they did not reach statistical significance (0,17 ± 0,04; p = 0.066). No differences were seen in all other parameters.ConclusionThe study suggests the existence of a relationship between PW and HP. This finding may be related to iodine intake during pregnancy.  相似文献   
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Healthy dietary intake has been acknowledged for decades as one of the main contributors to health. More recently, the field of nutritional psychiatry has progressed our understanding regarding the importance of nutrition in supporting mental health and cognitive function. Thereby, individual nutrients, including omega-3 fatty acids and polyphenols, have been recognized to be key drivers in this relationship. With the progress in appreciating the influence of dietary fiber on health, increasingly research is focusing on deciphering its role in brain processes. However, while the importance of dietary fiber in gastrointestinal and metabolic health is well established, leading to the development of associated health claims, the evidence is not conclusive enough to support similar claims regarding cognitive function. Albeit the increasing knowledge of the impact of dietary fiber on mental health, only a few human studies have begun to shed light onto the underexplored connection between dietary fiber and cognition. Moreover, the microbiota-gut-brain axis has emerged as a key conduit for the effects of nutrition on the brain, especially fibers, that are acted on by specific bacteria to produce a variety of health-promoting metabolites. These metabolites (including short chain fatty acids) as well as the vagus nerve, the immune system, gut hormones, or the kynurenine pathway have been proposed as underlying mechanisms of the microbiota-brain crosstalk. In this minireview, we summarize the evidence available from human studies on the association between dietary fiber intake and cognitive function. We provide an overview of potential underlying mechanisms and discuss remaining questions that need to be answered in future studies. While this field is moving at a fast pace and holds promise for future important discoveries, especially data from human cohorts are required to further our understanding and drive the development of public health recommendations regarding dietary fiber in brain health.  相似文献   
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