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41.
Estrogen is a negative regulator of lymphopoiesis and provides an experimental tool for probing relationships between lymphocyte precursors and stem cells. We found that expression of lymphocyte-associated genes and immunoglobulin (Ig) gene rearrangement occurred before CD45R acquisition. Lymphoid-restricted progenitors that were Lin(-)IL-7R alpha(+)c-kit(lo)TdT(+) (lineage marker(-), interleukin receptor 7 alpha(+), c-kit(lo) and terminal deoxynucleotidyl transferase(+)) were selectively depleted in estrogen-treated mice; within a less differentiated Lin-c-kit(hi) fraction, functional precursors of B and T, but not myeloid, cells were also selectively depleted. TdT and an Ig heavy chain transgene were detected within a hormone-regulated Lin(-)c-kit(hi)Sca-1(+)CD27(+)Flk-2(+)IL-7R alpha(-) subset of this multipotential progenitor population. Identification of these extremely early lymphoid precursors should facilitate investigation of the molecular mechanisms that control lineage-fate decisions in hematopoiesis. 相似文献
42.
The negative role exerted by cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) in the regulation of T-cell activity, as induced by T-cell receptor (TCR)/CD3 and CD28 costimulation, has been widely described. In the present work we investigated the role of CTLA-4 in the control of cell activation, as induced by costimulation of the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) in murine CD4+ T cells. Results show that CTLA-4 engagement inhibits interleukin-2 (IL-2) production, not only when induced by CD3/CD28 costimulation, but also when CD4+ T cells are costimulated by anti-CD3 and anti-LFA-1 monoclonal antibodies (mAbs). LFA-1 has been described to induce Ca2+ mobilization also in the absence of TCR engagement. Moreover, we found that CTLA-4 engagement negatively affects Ca2+ mobilization and NF-AT activation, as induced by LFA-1 engagement alone. PLCgamma1 phosphorylation was also dampened within minutes after CTLA-4 engagement. Altogether these data indicate that through the control of signals induced by different receptors, CTLA-4 could be a global attenuator of T-cell activation. 相似文献
43.
Using an isolate of West Nile virus (WNV) from lineage 1 (Goose/Israel 1998), groups of specific pathogen free chickens were experimentally infected via the subcutaneous or intravenous routes. To evaluate the relative efficiency of detecting the virus in the infected chickens, samples from a range of tissues and organs were examined by virus isolation tests in tissue culture, including Vero, primary chicken embryo liver and fibroblast cells, and polymerase chain reaction (PCR) analyses. Additionally, in order to investigate the serological response of the chickens and produce WNV monospecific antibodies, serum samples were collected from the birds during the trial and analysed for antibodies by virus neutralization (VN) and the plaque-reduction neutralization test (PRNT). No clinical signs or gross pathological changes were seen in any of the inoculated chickens throughout the study. The nested PCR used in the study appeared to be significantly more sensitive at detecting the presence of the virus in both the tissues and the inoculated Vero cell cultures compared with the detection of gross cytopathic changes as observed in infected Vero cell culture. No cytopathic changes were seen in the inoculated avian cell cultures. Following primary inoculation of the chickens there was a weak antibody response 15 days post-inoculation. However, following re-inoculation with inactivated WNV and adjuvant there was a substantial increase in the neutralizing antibody titres when tested 2 weeks later. The results obtained suggested that the PRNT was more sensitive than the conventional VN test. Based on detection of virus and serology there was no evidence of viral transmission to the close contact controls. It can be concluded that the PCR used in this study was more sensitive than virus isolation for the detection of WNV while the PRNT also appeared more sensitive than the conventional VN test. 相似文献
44.
Marine Baillat Vanessa Pauly Gina Dagau Julie Berbis Farid Boubred Laurence Fayol 《Nutrients》2021,13(1)
The purpose of this study was to determine the influence of first-week nutrition intake on neonatal growth in moderate preterm (MP) infants. Data on neonatal morbidity and nutrition intake on day of life 7 (DoL7) were prospectively collected from 735 MP infants (320/7–346/7 weeks gestational age (GA)). Multivariable regression was used to assess the factors associated with extrauterine growth restriction (EUGR) defined as a decrease of more than 1 standard deviation (SD) in the weight z-score during hospitalization. Mean (SD) gestational age and birth weight were 33.2 (0.8) weeks and 2005 (369) g. The mean change in the weight z-score during hospitalization was −0.64 SD. A total of 138 infants (18.8%) had EUGR. Compared to adequate growth infants, EUGR infants received 15% and 35% lower total energy and protein intake respectively (p < 0.001) at DoL7. At DoL7, each increase of 10 kcal/kg/d and 1 g/kg/d of protein was associated with reduced odds of EUGR with an odds ratio of 0.73 (95% CI, 0.66–0.82; p < 0.001) and 0.54 (0.44–0.67; p < 0.001), respectively. Insufficient energy and protein intakes on DoL7 negatively affected neonatal growth of MP infants. Nutritional support should be optimized from birth onwards to improve neonatal weight growth. 相似文献
45.
Vanessa S. Sakalidis Alethea Rea Sharon L. Perrella Jacki McEachran Grace Collis Jennifer Miraudo Stuart A. Prosser Lisa Y. Gibson Desiree Silva Donna T. Geddes 《Nutrients》2021,13(6)
During the COVID-19 pandemic, breastfeeding women have experienced restricted access to support, placing them at increased risk of mental health concerns and limited breastfeeding assistance. This study investigated the effect of the pandemic on feeding choices and maternal wellbeing amongst breastfeeding mothers living in Australian and New Zealand. We conducted a cross-sectional online survey that examined feeding methods, maternal mental wellbeing, worries, challenges, and positive experiences during the pandemic. Most women were exclusively breastfeeding (82%). Partial breastfeeding was associated with perceived low milk supply and longer pregnancy duration during the pandemic. Reduced mental health and wellbeing was associated with lower levels of family functioning, increased perceived stress, and perinatal anxiety. Longer pregnancy duration during the pandemic was associated with lower mental health wellbeing scores, while higher perceived stress scores were reported for regions with higher COVID-19 infection rates and women with perceived low milk supply. Women reported that the pandemic resulted in less pressure and more time for family bonding, while worries about the pandemic, family health, and parenting challenges were also cited. Mental health concerns of breastfeeding women appear to be exacerbated by COVID-19, highlighting a critical need for access to mental health and broader family support during the pandemic. 相似文献
46.
Francisca de Castro Mendes Kirstie Ducharme-Smith Gustavo Mora-Garcia Saleh A. Alqahtani Maria Stephany Ruiz-Diaz Andre Moreira Rodrigo Villegas Vanessa Garcia-Larsen 《Nutrients》2021,13(6)
Increasing epidemiological evidence suggests that optimal diet quality helps to improve preservation of lung function and to reduce chronic obstructive pulmonary disease (COPD) risk, but no study has investigated the association of food insecurity (FI) and lung health in the general population. Using data from a representative sample of US adults who participated in the National Health and Nutrition Examination Survey (NHANES) 2007–2012 cycles, we investigated the association between FI with lung function and spirometrically defined COPD in 12,469 individuals aged ≥ 18 years of age. FI (high vs. low) was defined using the US Department of Agriculture’s Food Security Scale). Population-weighted adjusted regression models were used to investigate associations between FI, and forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), their ratio, and spirometrically defined restriction (FVC below the lower limit of normal) and airflow obstruction (COPD). The prevalence of household FI was 13.2%. High household FI was associated with lower FVC (adjusted β-coefficient −70.9 mL, 95% CI −116.6, −25.3), and with higher odds (OR) of spirometric restriction (1.02, 95% CI 1.00, 1.03). Stratified analyses showed similar effect sizes within specific ethnic groups. High FI was associated with worse lung health in a nationally representative sample of adults in the US. 相似文献
47.
Helmut Schrder Vanessa Cruz Muoz Marta Urquizu Rovira Victoria Valls Ibaez Josep-Maria Manresa Domínguez Gerard Ruiz Blanco Monserrat Urquizu Rovira Pere Toran Monserrat 《Nutrients》2021,13(6)
Increasing sugar-sweetened beverages (SSB) consumption and associated health impacts warrant health-policy action. We assessed associations of socioeconomic and lifestyle variables with adolescents’ consumption of regular soda (RSD), sport (SD), and energy (ED) drinks. Cross-sectional study of 3930 Spanish adolescents (2089 girls, 1841 boys) aged 13–18 years). We compared frequency of consuming each SSB type (European Food Safety Authority questionnaire) with sociodemographic and lifestyle variables (standardized questions). RSD, SD, and ED were consumed at least weekly by 72.7%, 32.3%, and 12.3% of participants, respectively, and more frequently (p < 0.001) by boys, compared to girls. Multivariate ordinal logistic regression showed inverse association between RSD, SD, and ED consumption and parental occupation-based socioeconomic status (p < 0.01). Daily smoking was associated (p < 0.001) with higher ED (OR 3.64, 95% CI 2.39–5.55) and RSD (OR 2.15, 95% CI 1.56–2.97) consumptions. SD intake was associated inversely with smoking (OR 0.60, 95% CI 0.40–0.89, p = 0.012) and directly with physical activity (OR 2.93, 95% CI 2.18–3.95, p < 0.001). School performance was lower among ED (OR 2.14, 95% CI, 1.37–3.35, p = 0.001) and RSD (OR 1.81, 95% CI 1.24–2.64, p = 0.002) consumers, compared to SD. Maleness and low socioeconomic status predicted SSB consumption. Smoking and low school performance were associated with higher ED and RSD intakes. 相似文献
48.
Asher Y. Rosinger Samantha M. Olson Sascha R. Ellington Janice Perez-Padilla Regina M. Simeone Caitlin S. Pedati Betsy A. Schroeder Gilberto A. Santiago Freddy A. Medina Jorge L. Muoz-Jordn Laura E. Adams Romeo R. Galang Miguel Valencia-Prado Sonia Bakkour Candimar Coln Mary Goodwin Dana Meaney-Delman Jennifer S. Read Lyle R. Petersen Denise J. Jamieson Carmen C. Deseda Margaret A. Honein Brenda Rivera-García Carrie K. Shapiro-Mendoza 《Emerging infectious diseases》2021,27(5):1505
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015–2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens. 相似文献
49.
Costa Davidson Ribeiro Pessoa Diego Rodrigues Seefeldt Vanessa Borelli Costa David Ribeiro Maia Daniel Tineu Leite dos Santos Maciel Thiago Mota Brenda Barros Magalhães Delpasso Carolina Alves Ribeiro Camila Alves Delpasso Nicolau Renata Amadei 《Lasers in medical science》2021,36(8):1681-1689
Lasers in Medical Science - This study compared the effects of LED therapy associated with occlusal splint (OS) on the signs and symptoms of temporomandibular disorder (TMD). In this randomized,... 相似文献
50.