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1.
Tebuconazole is a systemic follicular fungicide known to cause diverse problems in non-target organisms namely associated to the pure active ingredient. As such, the objective of this work was to evaluate developmental changes induced by a tebuconazole commercial formulation to a non-target animal model. Zebrafish embryos at ± 2 h post-fertilization were exposed to tebuconazole wettable powder concentrations (0.05, 0.5 and 5 mg L-1) for 96 h with developmental toxicity assessed throughout the exposure period and biochemical parameters evaluated at the end of the exposure. Behavioural assessment (spatial exploration and response to stimuli) was conducted 24 h after the end of the exposure. While no developmental and physiological alterations were observed, exposure to tebuconazole resulted in an increased generation of reactive oxidative species at the 0.05 and 0.5 mg L-1 concentrations and a decreased GPx activity at the 0.5 mg L-1 concentration suggesting a potential protection mechanism. There was also a change in the avoidance-escape behaviour supporting an anxiolytic effect suggesting possible alterations in the central nervous system development demanding further studies. 相似文献
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《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals. 相似文献
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《Health & place》2022
An accumulating body of evidence has associated exposure to greenspace with improved birth outcomes, including higher birth weight and lower risk of low birth weight; however, evidence on such association with in-utero fetal growth is scarce. We explored the influence of maternal exposure to residential greenspace and fetal growth in four INMA (Infancia y Medio Ambiente) Spanish birth cohorts (2003–2008), with 2,465 participants. Residential greenspace was characterised by the Normalised Difference Vegetation Index (NDVI) average across 100 m, 300 m, and 500 m buffers around the residence. Repeated ultrasound measurements of the abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW) were used. We created customised-generalised least squares models to evaluate associations of residential greenspace exposure on each fetal growth parameter, controlled for the relevant confounders. There were associations between the 500 m buffer and BPD, FL, and AC. We also found associations in the 300 m buffer and FL and AC. The associations in the 100 m buffer were null. Estimates were higher among participants with lower socioeconomic status. Mediation analyses found that air pollution might explain 15–37% of our associations. Mediation by physical activity was not observed. Greenspace exposure may be beneficial for fetal growth. 相似文献
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地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分,其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊(EnpolypHaga fibrinolytic protein oral colon targeting microcapsules, CTM-EFP)。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜(SEM)显示微囊呈球形、表面光滑,在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %,在人工胃液中24 h累积释放度为7.43 ± 1.04 %,通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程,提示地鳖纤溶活性蛋白(EnpolypHaga fibrinolytic protein, EFP)是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型,为EFP应用于临床提供参考。 相似文献
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目的:探讨赣南地区原发性肺鳞癌患者EGFR和ALK基因突变的特点,科学指导此类患者优选靶向用药。方法:入组73例原发性肺鳞癌病例,采用ARMS-PNA技术检测EGFR基因第18、19、20、21外显子突变,应用不平衡法检测其中60例病例的ALK融合基因,回顾性分析EGFR和ALK基因突变患者的临床病理特征。结果:EGFR基因突变8例,阳性率为10.96%(8/73),4例为L858R突变,3例为19del突变,1例为G719X突变。女性患者突变率(66.67%,2/3)明显高于男性患者(8.57%,6/70)(P=0.030),EGFR基因突变在高龄(≥60岁)、进展期(N_(1-3)、Ⅲ+Ⅳ期)患者中相对较高,但差异无统计学意义(P>0.05)。EGFR基因突变与吸烟史、T分期以及肿瘤分布位置均无相关性(P>0.05);ALK融合基因表达2例,阳性率3.33%(2/60),与患者性别、年龄、吸烟史、TNM分期及肿瘤分布类型等各临床病理特征均无相关性(P>0.05);未发现EGFR和ALK基因共存突变病例。结论:赣南地区原发性肺鳞癌患者EGFR和ALK基因突变率相对不高,EGFR基因突变以L858R和19del突变为主,且好发于女性患者,可能是患者病情进展的预测因子之一。 相似文献
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《The British journal of oral & maxillofacial surgery》2022,60(4):499-506
The aim of this study was to carry out a retrospective multicentre study comparing the morphological outcome of 8 techniques used for the management of sagittal synostosis versus a large cohort of control patients. Computed tomographic (CT) images were obtained from children CT-scanned for non-craniosynostosis related events (n = 241) and SS patients at preoperative and postoperative follow-up stages (n = 101). No significant difference in morphological outcomes was observed between the techniques considered in this study. However, the majority of techniques showed a tendency for relapse. Further, the more invasive procedures at older ages seem to lead to larger intracranial volume compared to less invasive techniques at younger ages. This study can be a first step towards future multicentre studies, comparing surgical results and offering a possibility for objective benchmarking of outcomes between methods and centres. 相似文献
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