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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   
2.
Oocyte and embryo grading is one of the most important steps in assisted reproductive technology to identify the best among cultured embryos for transfer or vitrification. The most commonly used non-invasive method is morphological assessment of gametes and embryos using a microscope. This method despite being simple and cost-effective has interobserver and intraobserver variability and subjectivity and has little to offer about the physiological state of embryos. This review sourced research articles and reviews pertaining to other non-invasive assessment methodologies from Medline and PubMed to collate latest technologies in vogue and identify novel methodologies of the future. The review assesses the current understanding in oocyte and embryo grading and touches upon novel non-invasive techniques and potential biomarkers to identify the best embryo. The latest available literature on time-lapse imaging, hierarchical algorithms, omics (consisting of proteomics and secretomes), miRNAs, mitochondrial RNAs and artificial intelligence has been accessed to summarize the enormous information available, to identify gaps in current interpretations, to identify emerging technologies and to provide direction for future research. This review will greatly benefit anyone practicing assisted reproduction and clinical embryology.  相似文献   
3.
The aim of this retrospective study was to investigate the accuracy of dynamic navigation for the placement of intentionally tilted implants in the posterior maxilla. The study included 12 patients with edentulism or continuous multiple tooth loss, who had 48 implants inserted under dynamic navigation guidance in the posterior maxilla. Twenty-four implants near maxillary sinuses were intentionally tilted. The average platform deviation was 1.3 ± 0.4 mm (range 0.8–2.3 mm), apex deviation was 1.1 ± 0.5 mm (range 0.2–2.3 mm), and axis deviation was 3.1 ± 1.0° (range 1.8–6.7°). The other 24 implants were axially positioned. The average platform deviation was 1.5 ± 0.5 mm (range 0.7–3.1 mm), apex deviation was 1.3 ± 0.7 mm (range 0.5–3.1 mm), and axis deviation was 3.2 ± 1.5° (range 1.5–7.7°). There was no significant difference in platform deviation, apex deviation, or axis deviation between the tilted implants and implants in the axial position (P > 0.05). This analysis indicates that a dynamic navigation system can be used as a method of guidance to place intentionally tilted implants as accurately as axially positioned implants in the posterior maxilla, thereby preventing damage to the maxillary sinuses and the need to graft bone.  相似文献   
4.
Mechanical intravascular hemolysis is frequently observed following procedures on heart valves and uncommonly observed in native valvular disease. In most cases, its severity is mild. Nevertheless, it can be clinically significant and even life threatening, requiring multiple blood transfusions and renal replacement therapy. This paper reviews the current knowledge on mechanical intravascular hemolysis in valvular disease, before and after correction, focusing on pathophysiology, approach to diagnosis, and impact of other hematological conditions on the resultant anemia. The importance of a multidisciplinary management is underscored. Laboratory data are provided about subclinical hemolysis that is commonly observed following the implantation of surgical and transcatheter valve prostheses and devices. Finally, clinical scenarios are reviewed and current medical and surgical treatments are discussed, including alternative options for inoperable patients.  相似文献   
5.
《Acta histochemica》2022,124(8):151973
Maternal recognition of pregnancy in llamas would be related to a still-unknown signal secreted by the embryo to extend the corpus luteum lifespan. In order to study llamas reproductive physiology and early pregnancy aspects, research on embryos between 8 and 12 days post-mating is essential. However, there is a lack of information on llama embryo paraffin embedding, a procedure that exhibits difficulties, mostly for embryo manipulation. This work presents an accessible, easy and rapid protocol for embedding llama blastocysts. Uterine flushings from four superovulated llamas were performed to recover embryos 8 days post-mating. Each embryo was fixed in 1 ml of 10 % neutral buffered formalin for 24 h, at 4 °C, and transferred to 70 % ethanol. Later, they were submitted to a series of baths: 500 µl PBS with 5 % bovine foetal serum solution (PBS+BFS) for 1 min; zona pellucida permeabilization with 500 µl PBS with 0.2 % Triton X-100 for 20 min; 500 µl PBS+BFS for 1 min; dehydration on baths with ascendent grades of ethanol (70 %, 96 %, and 100 % twice) for 10 min each; and bath of butanol for 5 min. Finally, embryos were embedded in a pellet of paraffin and afterwards in a paraffin block. Complete sections from 8 of 13 grade I and II embryos were obtained. In conclusion, by applying this method, good quality sections with preserved embryo morphology suitable for histological, histochemical or immunohistochemical approaches would be possible to acquire.  相似文献   
6.
7.
目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。  相似文献   
8.
胚胎植入是一个复杂且受到高度调控的过程,需要囊胚与母体子宫内膜的发育精确同步。胞饮突作为表达于子宫内膜上的一种特殊膜状突起,随月经周期变化表现为不同形态,可分为发育期、成熟期及退化期。目前已有一系列研究证实,胞饮突的数量、覆盖面积及发育阶段等在预测不孕女性种植窗及评估子宫内膜容受性中具有临床价值。胞饮突评分较高、覆盖面积较广且成熟期胞饮突占比较高的女性妊娠结局更佳。其机制可能包括胞饮突通过调节宫腔内容物影响子宫内膜容受性、通过表达植入相关蛋白参与囊胚-子宫内膜相互作用等。然而,对胞饮突精准且客观的评估手段仍待进一步探索,胞饮突评估子宫内膜容受性的精确度也待进一步验证。  相似文献   
9.
目的探讨胆总管结石患者采用内镜逆行胰胆管造影术(ERCP)取石后同期开展胆道支架置入术或开展经内镜鼻胆管引流术(ENBD),对于防范并发症的价值。 方法按照前瞻性研究原则,选择2017年4月至2019年1月新疆医科大学第一附属医院收治的338例胆总管结石患者,随机分为支架组(170例)与引流组(168例)。两组患者均行ERCP治疗,其中引流组术后同期开展ENBD,支架组患者术后开展胆道支架置入术,对比两组患者腹痛评分、并发症发生情况及预后。 结果两组患者术后均未合并严重出血、穿孔或病死,结石完全清除率差异无统计学意义。与支架组相比,引流组术中胰腺管插管次数,术后4 h血淀粉酶水平、高淀粉酶血症、急性胰腺炎以及并发症总发生率更高,差异有统计学意义(P<0.05),术后24、48、72 h不同时点腹痛测评分值居更高水平(P<0.05)。 结论对于胆总管结石行ERCP治疗的患者,术后予以ENBD、胆道支架置入术的结石完全清除效果对比无明显差异,但胆道支架置入术更能降低术后并发症风险、缓解腹痛症状,患者获益更多。  相似文献   
10.
Nanoparticles have found use in a wide range of applications, mainly as carriers of active biomolecules. It is thus necessary to assess their toxicity for human health, as well as for the environment, on which there is still a gap of knowledge. In this work, sea urchin Paracentrotus lividus, a widely used model for embryotoxicity and spermiotoxicity, has been used to assess potential detrimental effects of amino-functionalized mesoporous silica nanoparticles (NH2-MSiNPs) on embryonic development. Specifically, gametes quality, embryogenesis morphological and timing alterations, and cellular stress markers, such as mitochondrial functionality, were assessed in presence of different concentrations of NH2-MSiNPs in filtered seawater (FSW). Furthermore, dorsal-ventral axis development and skeletogenesis were characterized by microscopy imaging and gene expression analysis. NH2-MSiNPs determined a strong reduction in the egg fertilization rate. Consequently, the presence of NH2-MSiNPs resulted detrimental in P. lividus embryonic development, with severe morphological alterations correlated with an increased embryos mortality. Finally, NH2-MSiNPs treatment was responsible for other toxic effects, such as reduced mitochondrial function and skeletogenesis alterations, according to the reduced mineralization sites in the endoskeleton formation and the related genes altered expression. Taken together, these results suggest the potential toxic effects of NH2-MSiNPs on the marine ecosystem, with consequences for the development and reproduction of its organisms. Despite their promising potential as carriers of biomolecules, it is pivotal to consider that their uncontrolled use may result harmful to the environment and, consequently, to living organisms.  相似文献   
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