1,153 research outputs found

    The influence of the menstrual cycle and hormonal contraceptives on cardiorespiratory fitness in physically active women: A systematic review and meta-analysis.

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    OBJECTIVE To systematically review and summarize the existing evidence related to the influence of the menstrual cycle (MC) and hormonal contraceptive (HC) use on O2max in physically active women. METHODS This systematic review and meta-analysis conforms to the PRISMA statement guidelines. Four (sub-)meta-analyses were performed. Two focused on longitudinal studies examining the same women several times to compare the O2max during the different menstrual phases or oral contraceptive (OC) use and withdrawal. Two meta-analyses examined if there is a difference in O2max between OC users and normally menstruating women by analyzing cross-sectional studies assigning physically active women to one of these two groups as well as intervention-based studies (cross-over studies, randomized controlled trials considering only the data of the intervention group) comparing women intra-individually with and without OCs. RESULTS Nine of the included studies (107 women) evaluated the influence of the MC, five studies (69 women) the impact of OCs on O2max, and six studies investigated both topics (88 women). A mean difference of O2max -0.03 ml/kg/min (95%CI -1.06 to 1.01) between the early follicular and luteal menstrual phase was observed. Between the active and inactive phases of OCs, a mean difference of -0.11 ml/kg/min (95%CI -2.32 to 2.10) was found. The inter-individual comparison of naturally menstruating women and OC users showed a mean difference in O2max of 0.23 ml/kg/min (95% CI -2.33 to 2.79) in favor of OC use. The intra-individual comparison of the same women showed a mean decrease in O2max of -0.84 ml/kg/min (95% CI -2.38 to 0.70) after a new start with OCs. CONCLUSIONS Our meta-analyses showed no effects of the MC or the OCs on O2max. More high-quality studies are needed determining the MC phases more precisely, including OCs with the current standard formulations and comparing the influence of different progestins

    Cytokinin response factors regulate PIN-FORMED auxin transporters

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    Auxin and cytokinin are key endogenous regulators of plant development. Although cytokinin-mediated modulation of auxin distribution is a developmentally crucial hormonal interaction, its molecular basis is largely unknown. Here we show a direct regulatory link between cytokinin signalling and the auxin transport machinery uncovering a mechanistic framework for cytokinin-auxin cross-talk. We show that the CYTOKININ RESPONSE FACTORS (CRFs), transcription factors downstream of cytokinin perception, transcriptionally control genes encoding PIN-FORMED (PIN) auxin transporters at a specific PIN CYTOKININ RESPONSE ELEMENT (PCRE) domain. Removal of this cis-regulatory element effectively uncouples PIN transcription from the CRF-mediated cytokinin regulation and attenuates plant cytokinin sensitivity. We propose that CRFs represent a missing cross-talk component that fine-tunes auxin transport capacity downstream of cytokinin signalling to control plant development

    Selection of prebiotic oligonucleotides by cyclic phase separation

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    The emergence of functional oligonucleotides on early Earth required a molecular selection mechanism to screen for specific sequences with prebiotic functions. Cyclic processes such as daily temperature oscillations were ubiquitous in this environment and could trigger oligonucleotide phase separation. Here, we propose sequence selection based on phase separation cycles realized through sedimentation in a system subjected to the feeding of oligonucleotides. Using theory and experiments with DNA, we show sequence-specific enrichment in the sedimented dense phase, in particular of short 22-mer DNA sequences. The underlying mechanism selects for complementarity, as it enriches sequences that tightly interact in the condensed phase through base-pairing. Our mechanism also enables initially weakly biased pools to enhance their sequence bias or to replace the most abundant sequences as the cycles progress. Our findings provide an example of a selection mechanism that may have eased screening for the first auto-catalytic self-replicating oligonucleotides

    Cordyceps sinensis biomass produced by submerged fermentation in high-fat diet feed rats normalizes the blood lipid and the low testosterone induced by diet

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    This study investigated the effect of Cordyceps sinensis biomass supplementation obtained from submerged fermentation on blood lipid and low testosterone induced by high-fat diet (HFD). The experiments were carried out using a long-term intake of HFD and HFD plus Simvastatin or C. sinensis (4 months). Our results show that plasma cholesterol, triglycerides and LDL were decreased by Cordyceps sinensis biomass supplementation (CSBS). A longterm intake of HFD caused a significant liver damage which has been reverted by CSBS. CSBS normalized decreasing testosterone levels observed in high-fat diet feed rats. All these findings lead us to suggest that C. sinensis was able to decrease blood lipid concentration, increase hepatoprotective activity and normalize testosterone levels

    ADENOCARCINOMA PAPILAR DEL CUELLO UTERINO: COMUNICACIÓN DE UN CASO Y REVISIÓN DE LA LITERATURA

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    Se presenta el caso clínico de una paciente de 42 años con diagnóstico de adenocarcinoma seroso papilar del cuello uterino etapa Ib1 tratada mediante histerectomía radical más linfadenectomía pélvica bilateral. El estudio anatomopatológico demostró bordes quirúrgicos libres y ausencia de enfermedad metastásica ganglionar por lo que se consideró a la paciente tratada. Este es el primer caso de adenocarcinoma seroso papilar del cuello uterino reportado en el país. Hay que descartar el compromiso cervical secundario por tumores serosos de endometrio, ovario o trompa antes de plantear el origen primario de cuello uterino. No se conoce el real comportamiento, pronóstico y óptimo tratamiento en este tipo de tumores. La determinación de los niveles de CA-125 basal y seriados durante el seguimiento pudiese ser de utilidad en la evaluación del tratamiento realizado y en la sospecha de enfermedad persistente o reciPad

    A comunidade de insetos endófagos de Asteraceae em Cerrados de São Paulo

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    A survey of the endophagous insects fauna associated to Asteraceae capitula was carried out from 2000 to 2002 in eight cerrado sensu stricto sites located in the Brazilian state of São Paulo. Sixty-four endophagous species of Diptera and Lepidoptera were recorded from 49 asteracean host plants. Approximately half of the species were obtained from a single locality, with a large proportion emerging from a single sample (unicates). Thirty percent of the species were singletons (i.e. only one individual was recorded). The large proportion of rare species suggests a high species turnover among localities. Lepidopteran species were recorded on more host species than dipterans, confirming their more polyphagous food habit, also observed in other Brazilian biomes and in Europe. We conclude that the studied cerrado localities, all within São Paulo State, are isolated with its invertebrate fauna composed of many rare and exclusive species. We suggest that the maintenance of Asteraceae biodiversity and their endophagous insects depend on the conservation of all cerrado remnants in the state.No presente estudo foi realizado um levantamento da fauna de insetos endófagos de capítulos de Asteraceae (Compostas), de 2000 a 2002, em oito localidades de cerrados sensu stricto no estado de São Paulo. Foram obtidas 64 espécies de endófagos (dípteros e lepidópteros) de 49 espécies de hospedeiras. Aproximadamente metade das espécies foi obtida de apenas uma área, e destas uma grande proporção ocorreu em apenas uma amostra (unicatas). Trinta por cento das espécies foram consideradas singletons (apenas um indivíduo foi obtido). A grande quantidade de espécies raras sugere uma forte troca de espécies entre diferentes áreas. Lepidópteros foram registrados em mais espécies hospedeiras que dípteros, confirmando o já observado para o mesmo sistema de insetos e plantas em outros ambientes no Brasil e Europa. As áreas de cerrado sensu stricto estudadas no estado de São Paulo encontram-se isoladas, com uma grande parte da fauna de invertebrados composta por muitas espécies raras e exclusivas. Diante deste quadro, sugere-se que a manutenção da biodiversidade de Asteraceae e seus endófagos em seus níveis atuais depende da conservação de todo o conjunto de remanescentes de cerrado do estado.458468Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Smoking susceptibility as a predictive measure of cigarette and e-cigarette use among early adolescents

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    Objective. To assess the validity of a standard measure of smoking susceptibility for predicting cigarette and e-cigarette use in a sample of early adolescents in Argentina and Mexico. Materials and methods. A school-based longitudinal survey was conducted in 2014-16 among secondary students. We analyzed students who were never smokers of regular cigarettes or e-cigarettes at baseline and who completed both surveys. The main independent variable was smoking susceptibility. Multilevel logistic regression models were used, adjusting for sociodemographic and personal variables, social network use of cigarettes and exposure to advertising. Results. In the adjusted analysis, smoking susceptibility independently predicted cigarette initiation (Argentina: AOR 2.28; 95%CI 1.66-3.14; Mexico: AOR 2.07; 95%CI 1.74-2.45) and current smoking (Argentina: AOR 3.61; 95%CI 2.48-5.24; Mexico: AOR 1.69; 95%CI 1.29-2.22); however, it only predicted e-cigarette initiation in Mexico (Mexico: AOR 1.29; 95%CI 1.02-1.63). Conclusion. Smoking susceptibility was a valid measure to predict future cigarette smoking in this sample

    Bisphenol A exposure in Mexico City and risk of prematurity: a pilot nested case control study

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    Abstract Background Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. Methods A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. Results BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 μg/L to 6.7 μg/L; uncorrected geometric mean was 1.52 μg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). Conclusions This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks.http://deepblue.lib.umich.edu/bitstream/2027.42/78251/1/1476-069X-9-62.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78251/2/1476-069X-9-62.pdfPeer Reviewe

    The First Report of mcr-1-Carrying Escherichia coli Originating from Animals in Serbia

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    The aim of this study was continuous monitoring of the presence of mcr-1 to mcr-5 genes in Enterobacterales isolated from cattle, pigs, and domestic poultry at intensive breeding facilities in Northern Vojvodina, Serbia, from 1 January 1 to 1 October 2020. Out of 2167 examined samples, mcr-1 was observed in five E. coli isolates originating from healthy turkeys. Four isolates belonged to the phylogenetic group B1, and one isolate to the phylogenetic group A. Detected E. coli serogenotypes (somatic O and flagellar H antigens) were O8:H25 and O29:H25. Core-genome multi-locus sequence typing (cgMLST) revealed three ST58 isolates clustering together in Clonal Complex (CC) 155 and two singletons of ST641-CC86 and ST410-CC23, respectively. Clonotyping revealed CH4-32 (n = 3), CH6-53 (n = 1) and CH4-24 (n = 1). In all isolates, the mcr-1 gene was located on a large IncX4 replicon type plasmid. Eight virulence-associated genes (VAGs) typical of avian pathogenic E. coli (APEC) (fyuA, fimH, hlyF, iss, ompT, sitA, traT, iroN) were detected in four isolates. These isolates were investigated for susceptibility to four biocides and revealed MIC values of 0.125% for glutardialdehyde, of 0.00003–0.00006% for chlorohexidine, of 4–6% for isopropanol and of 0.001–0.002% for benzalkonium chloride. All obtained MIC values of the tested biocides were comparable to the reference strain, with no indication of possible resistance. This is the first report of mcr-1.1-carrying E. coli from Serbia. Although only samples from turkeys were mcr-positive in this study, continuous monitoring of livestock samples is advised to prevent a spill-over from animals to humans
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