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91.
Vitrification technology has shown great promise for cryopreservation of human embryos. The majority of this work has been with blastocyst-stage embryos. This report describes initial clinical results following vitrification of human embryos on day 3 of culture at the 6- to 8-cell stage. A total of 236 embryos were cryopreserved on cryoloops using a vitrification protocol. Warmed embryos were cultured until day 5 before transfer to the patient. The post-warming survival rate was 85%. The clinical pregnancy rate was 44% (34/77), and the implantation rate was 20% (40/201). In transfers where at least one warmed embryo reached the blastocyst stage by the day of transfer, the clinical pregnancy rate was 58% (28/48). The cryoloop was an excellent vessel for ultra-rapid cryopreservation of embryos. This study supports the effectiveness of a dimethylsulphoxide/ethylene glycol cryoprotectant combination for vitrification of human embryos at the 6- to 8-cell stage.  相似文献   
92.
目的:通过对患者是否合并高血压、年龄、性别、D-二聚体、同型半胱氨酸、C反应蛋白水平的研究,探讨高血压这一常见基础疾病与下肢深静脉血栓(DVT)形成之间存在何种相关性。方法:选取山西医科大学第一附属医院普外科在2008年6月至2013年5月入住并确诊为DVT的病人71例作为病例,随机选择同时期入住该院的非深静脉血栓形成病人71例作为对照。结果:病例组D-二聚体、C反应蛋白、同型半胱氨酸水平显著高于对照组(P〈0.05)。有高血压史的人群患DVT的危险性是非高血压人群患DVT的4.399倍,D-二聚体不正常的人群患DVT的危险性是正常人群的3.483倍,同型半胱氨酸不正常的人群患DVT的危险性是正常人群的4.337倍,C反应蛋白不正常的人群患DVT的危险性是正常人群的5.632倍。结论:下肢深静脉血栓形成好发于中老年人,高血压史增加了下肢深静脉血栓形成的危险性,D-二聚体、同型半胱氨酸、C反应蛋白可能与下肢深静脉血栓形成有关,高血压中D-二聚体、同型半胱氨酸、C反应蛋白水平的升高增加了患DVT的风险。  相似文献   
93.
The prevalence of obesity continues to rise, underscoring the need to better understand the pathways mediating adipose tissue (AT) expansion. Alltrans‐retinoic acid (atRA), a bioactive vitamin A metabolite, regulates adipogenesis and energy metabolism, and, in rodent studies, aberrant vitamin A metabolism appears a key facet of metabolic dysregulation. The relevance of these findings to human disease is unknown, as are the specific enzymes implicated in vitamin A metabolism within human AT. We hypothesized that in human AT, family 1A aldehyde dehydrogenase (ALDH1A) enzymes contribute to atRA biosynthesis in a depot‐specific manner. To test this hypothesis, parallel samples of subcutaneous and omental AT from participants (n = 15) were collected during elective abdominal surgeries to quantify atRA biosynthesis and key atRA synthesizing enzymes. ALDH1A1 was the most abundant ALDH1A isoform in both AT depots with expression approximately twofold higher in omental than subcutaneous AT. ALDH1A2 was detected only in omental AT. Formation velocity of atRA was approximately threefold higher (p = 0.0001) in omental AT (9.8 [7.6, 11.2]) pmol/min/mg) than subcutaneous AT (3.2 [2.1, 4.0] pmol/min/mg) and correlated with ALDH1A2 expression in omental AT (β‐coefficient = 3.07, p = 0.0007) and with ALDH1A1 expression in subcutaneous AT (β‐coefficient = 0.13, p = 0.003). Despite a positive correlation between body mass index (BMI) and omental ALDH1A1 protein expression (Spearman r = 0.65, p = 0.01), BMI did not correlate with atRA formation. Our findings suggest that ALDH1A2 is the primary mediator of atRA formation in omental AT, whereas ALDH1A1 is the principal atRA‐synthesizing enzyme in subcutaneous AT. These data highlight AT depot as a critical variable for defining the roles of retinoids in human AT biology.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Rodent data suggest that dysregulated production of alltrans‐retinoic acid (atRA), the primary bioactive metabolite of vitamin A, may contribute to body weight gain and its complications. However, the key enzymes responsible for atRA biosynthesis in human adipose tissue have not been identified, nor has the relationship between body weight and adipose tissue atRA biosynthesis been evaluated in humans.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This study sought to identify the key enzymes involved in atRA biosynthesis in human omental and subcutaneous adipose tissue. This study also quantified atRA formation velocity and explored the potential relationship between body mass index (BMI) and atRA biosynthesis in both adipose tissue depots.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
This study establishes that among the aldehyde dehydrogenase (ALDH) isoforms, ALDH1A1 and ALDH1A2 both contribute to atRA biosynthesis in human omental adipose tissue, whereas only ALDH1A1 contributes to atRA biosynthesis in subcutaneous adipose tissue. Both ALDH1A1 expression and atRA formation velocity are substantially higher in omental than subcutaneous adipose tissue. Omental ALDH1A1 protein expression exhibits a positive correlation with BMI, but atRA formation velocity in both omental and subcutaneous adipose tissue shows no correlation with BMI. Thus, these findings highlight discrepancies between human and rodent adipose tissue biology and, moreover, reveal depot‐specific regulation of vitamin A metabolism in human adipose tissue.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
This line of research ultimately is intended to define the roles of vitamin A metabolites in the regulation of tissue remodeling and energy partitioning in human adipose tissue. This knowledge could contribute to the delineation of mechanisms underlying progressive obesity and its complications.  相似文献   
94.
95.
The Kunjin strain of West Nile virus (WNVKUN) is a mosquito-transmitted flavivirus that can infect farmed saltwater crocodiles in Australia and cause skin lesions that devalue the hides of harvested animals. We implemented a surveillance system using honey-baited nucleic acid preservation cards to monitor WNVKUN and another endemic flavivirus pathogen, Murray Valley encephalitis virus (MVEV), on crocodile farms in northern Australia. The traps were set between February 2018 and July 2020 on three crocodile farms in Darwin (Northern Territory) and one in Cairns (North Queensland) at fortnightly intervals with reduced trapping during the winter months. WNVKUN RNA was detected on all three crocodile farms near Darwin, predominantly between March and May of each year. Two of the NT crocodile farms also yielded the detection of MVE viral RNA sporadically spread between April and November in 2018 and 2020. In contrast, no viral RNA was detected on crocodile farms in Cairns during the entire trapping period. The detection of WNVKUN and MVEV transmission by FTATM cards on farms in the Northern Territory generally correlated with the detection of their transmission to sentinel chicken flocks in nearby localities around Darwin as part of a separate public health surveillance program. While no isolates of WNVKUN or MVEV were obtained from mosquitoes collected on Darwin crocodile farms immediately following the FTATM card detections, we did isolate another flavivirus, Kokobera virus (KOKV), from Culex annulirostris mosquitoes. Our studies support the use of the FTATM card system as a sensitive and accurate method to monitor the transmission of WNVKUN and other arboviruses on crocodile farms to enable the timely implementation of mosquito control measures. Our detection of MVEV transmission and isolation of KOKV from mosquitoes also warrants further investigation of their potential role in causing diseases in crocodiles and highlights a “One Health” issue concerning arbovirus transmission to crocodile farm workers. In this context, the introduction of FTATM cards onto crocodile farms appears to provide an additional surveillance tool to detect arbovirus transmission in the Darwin region, allowing for a more timely intervention of vector control by relevant authorities.  相似文献   
96.
97.
Objective:Hepatocyte nuclear factor 4α (HNF4A) has been demonstrated to be an oncogene in gastric cancer (GC). However, the roles of different HNF4A isoforms derived from the 2 different promoters (P1 and P2) and the underlying mechanisms remain obscure.Methods:The expression and prognostic values of P1- and P2-HNF4A were evaluated in The Cancer Genome Atlas (TCGA) databases and GC tissues. Then, functional assays of P1- and P2-HNF4A were conducted both in vivo and in vitro. High-throughput RNA-seq was employed to profile downstream pathways in P1- and P2-HNF4A-overexpressing GC cells. The expression and gene regulation network of the candidate target genes identified by RNA-seq were characterized based on data mining and functional assays.Results:HNF4A amplification was a key characteristic of GC in TCGA databases, especially for the intestinal type and early stage. Moreover, P1-HNF4A expression was significantly higher in tumor tissues than in adjacent non-tumor tissues (P < 0.05), but no significant differences were found in P2-HNF4A expression (P > 0.05). High P1-HNF4A expression indicated poor prognoses in GC patients (P < 0.01). Furthermore, P1-HNF4A overexpression significantly promoted SGC7901 and BGC823 cell proliferation, invasion and migration in vitro (P < 0.01). Murine xenograft experiments showed that P1-HNF4A overexpression promoted tumor growth (P < 0.05). Mechanistically, RNA-seq showed that the cytokine-cytokine receptor interactions pathway was mostly enriched in P1-HNF4A-overexpressing GC cells. Finally, chemokine (C-C motif) ligand 15 was identified as a direct target of P1-HNF4A in GC tissues.Conclusions:P1-HNF4A was the main oncogene during GC progression. The cytokine-cytokine receptor interaction pathway played a pivotal role and may be a promising therapeutic target.  相似文献   
98.
The fungal secondary metabolite patulin is a mycotoxin widespread in foods and beverages which poses a serious threat to human health. However, no enzyme was known to be able to degrade this mycotoxin. For the first time, we discovered that a manganese peroxidase (MrMnP) from Moniliophthora roreri can efficiently degrade patulin. The MrMnP gene was cloned into pPICZα(A) and then the recombinant plasmid was transformed into Pichia pastoris X-33. The recombinant strain produced extracellular manganese peroxidase with an activity of up to 3659.5 U/L. The manganese peroxidase MrMnP was able to rapidly degrade patulin, with hydroascladiol appearing as a main degradation product. Five mg/L of pure patulin were completely degraded within 5 h. Moreover, up to 95% of the toxin was eliminated in a simulated patulin-contaminated apple juice after 24 h. Using Escherichia coli as a model, it was demonstrated that the deconstruction of patulin led to detoxification. Collectively, these traits make MrMnP an intriguing candidate useful in enzymatic detoxification of patulin in foods and beverages.  相似文献   
99.
In acute myeloid leukemia, there is an ongoing debate on the prognostic value of the early bone marrow assessment in patients receiving intensive therapy. In this retrospective study, we analyzed the prognostic impact of the early response in 1,008 patients with newly diagnosed acute myeloid leukemia, who were treated at our institution with intensive chemotherapy followed by consolidation chemotherapy and/or allogeneic hematopoietic stem cell transplantation (HSCT). We found that early blast persistence has an independent negative prognostic impact on overall survival, event-free survival and relapse-free survival. This negative prognostic impact may only be overcome in patients showing at least a partial remission at the early bone marrow assessment and who subsequently achieve blast clearance by additional induction chemotherapy prior to consolidation therapy with allogeneic HSCT. In accordance, we propose that the time slope of remission is an additional leukemia-related dynamic parameter that reflects chemosensitivity and thus may inform post-induction therapy decision-making. In addition to patient-related factors, European LeukemiaNet risk group, measurable residual disease monitoring and donor availability, this may particularly apply to European LeukemiaNet intermediate-risk patients, for whom a decision between consolidation chemotherapy and allogeneic HSCT remains challenging in many cases.  相似文献   
100.
Chiu CW  So NM  Lam WW  Chan KY  Sanderson JE 《Radiology》2003,226(3):717-722
PURPOSE: To assess the feasibility of combined perfusion and viability testing by using magnetic resonance (MR) imaging in one setting in patients with non-ST segment-elevation acute coronary syndromes. MATERIALS AND METHODS: The data of 13 patients (mean age, 68 years; range, 40-85 years) at high risk for myocardial infarction who underwent MR imaging at 1.5 T were reviewed. Risk factors were increased troponin T levels in seven, reversible ST depression on an electrocardiogram in four, history of myocardial infarction in two, and presence of heart failure in four. Cine imaging of the left ventricle was performed with a true-fast imaging with steady-state precession (FISP) sequence to assess the regional myocardial contraction and ejection fraction. After injection of 0.1 mmol per kilogram of body weight of gadopentetate dimeglumine, first-pass MR images were obtained by using an inversion-recovery true-FISP sequence at rest and during infusion of adenosine (140 microg/kg/min). Resting and stress images were assessed qualitatively for abnormal regional perfusion (hypoenhancement). The myocardium was divided into three radial segments corresponding to the three coronary artery territories. Delayed (after 15 minutes) contrast material-enhanced images were acquired with use of a segmented inversion-recovery fast low-angle shot sequence. Conventional coronary angiograms were compared with the first-pass images. A more than 50% stenosis in diameter in any coronary artery was considered substantial. Mann-Whitney test was used to assess any significant difference between the left ventricular ejection fraction (LVEF) in patients with and those without myocardial infarct. RESULTS: Mean LVEF was 51.5% (range, 30%-77%). First-pass stress perfusion studies depicted 25 segments of hypoenhancement in 11 patients. Comparison of first-pass perfusion defects with findings on coronary angiograms indicated an overall sensitivity of 92% (24 of 26) and specificity of 92% (12 of 13) in detection of substantial coronary artery disease. Infarcts detected from hyperenhancement on delayed contrast-enhanced images were present in eight segments (four were transmural) in five patients. No significant difference was noted in the LVEF between patients with and those without infarct (P =.724). CONCLUSION: Combined stress perfusion and viability MR imaging was feasible in patients with acute coronary syndromes. First-pass MR perfusion defects compare well with the presence of substantial coronary artery stenosis on conventional angiograms.  相似文献   
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