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1.
Bone morphogentic proteins (BMPs) play an important role in cardiac development. Using an in vitro explant analysis, we show that BMPs are crucial for myocardium formation. As a first approach to identify which BMP may be involved in myocardium formation in intra- and extracardiac mesenchyme in vivo, a survey of the expression patterns of BMP2, -4, -5, -6, and -7 mRNA is prepared by in situ hybridization in chicken embryonic hearts from HH5 to 44. During recruitment of mesodermal cells to the outflow tract myocardium (HH10-23), BMP2, -4, -5, and -7 mRNA are expressed in the distal myocardial border and the flanking mesenchyme. After completion, BMP2 and -4 mRNA become restricted to the mesenchyme and BMP5 and -7 mRNA to the myocardium. At the venous pole, BMP2, -5, and -7 mRNA are expressed in the distal myocardial border of the caval vein, while BMP2, -5, -6, and -7 mRNA are expressed in the distal myocardium around the pulmonary vein. BMP4 mRNA is expressed in the adjacent mesenchyme at both sides. During muscularization of the atrioventricular cushions and the tricuspid valve, the cardiomyocytes that protrude into the mesenchyme express BMP2, -4, -5, and -7 mRNA, whereas BMP6 mRNA is expressed in the cushion mesenchyme. The myocardial protrusions formed in the mesenchymal proximal outlet septum express BMP4, -5, and -7 mRNA, while BMP2 and -6 mRNA are expressed in the mesenchyme. The spatiotemporal expression patterns of these BMPs in relation to myocardium formation at the distal ends and within the heart suggest a role for BMPs in myocardium formation. During delamination of the valves, BMP4 and -6 mRNA are expressed at the ventricular side of the forming mitral valve, BMP4 mRNA at the ventricular side of the forming tricuspid valve, and BMP2, -4, and -6 mRNA at the vascular side of the forming semilunar valves.  相似文献   
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A modified multiplex PCR method for detection of nine Staphylococcus aureus enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, and sej) and one form of immunoreactive toxic shock syndrome toxin based on a previously published method (S. R. Monday and G. A. Bohach, J. Clin. Microbiol. 37:3411-3414, 1999) has been developed. The modified PCR protocol seems robust and gives reliable results.  相似文献   
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Germ cell tumors of the testis are a heterogeneous group of neoplasms that affect male adolescents and young adults. Wnt signaling pathway components have been shown to be actively involved in normal and malignant germ cell differentiation and progression. In this study, we aimed to explore the expression patterns of the secreted frizzled‐related protein (SFRP) and Disheveled protein family (DVL) in a subset of testicular germ cell tumors. Eighty‐five formalin‐fixed, paraffin‐embedded tissue samples of the primary germ cell tumors of the testis were stained against SFRP1, SFRP3, DVL1, and DVL2 proteins using immunohistochemistry. SFRP1 and SFRP3 exhibited lower expression in both seminomas and mixed/non‐seminomatous tumors, compared with atrophic/benign tissue (p < 0.001). SFRP3 expression was lower than SFRP1 expression within the seminoma group (p = 0.004), but not within the mixed/non‐seminomatous group (p = 0.409). The majority of the tested cases (27/28, 96%) exhibited low DVL1 protein expression (median 0%, range 0–90%). In contrast, 20 out of 22 tested cases (91%) exhibited strong expression of DVL2 protein (median 80%, range 0–100%). No significant difference in DVL1 and DVL2 protein expression was observed between seminomas and mixed/non‐seminomatous tumors (p = 0.68 and 0.29). The secreted frizzled‐related protein and disheveled protein family members appear to be actively involved in the pathogenesis of primary testicular germ cell tumors.  相似文献   
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IntroductionThere is limited literature on coronavirus disease 2019 (COVID -19) complications such as thromboembolism, cardiac complications etc. as possible trigger for stroke. Hence, we aim to evaluate the prevalence and outcomes of COVID-19 related cardiovascular complications and secondary infection and their possibility as potential triggers for the stroke.MethodsData from observational studies describing the complications [acute cardiac injury (ACI), cardiac arrhythmias (CA), disseminated intravascular coagulation (DIC), septic shock, secondary infection] and outcomes of COVID‐19 hospitalized patients from December 1, 2019 to June 30, 2020, were extracted following PRISMA guidelines. Adverse outcomes defined as intensive care units, oxygen saturation less than 90%, invasive mechanical ventilation, severe disease, and in‐hospital mortality. The odds ratio and 95% confidence interval were obtained, and forest plots were created using random‐effects models. A short review of these complications as triggers of stroke was conducted.Results16 studies with 3480 confirmed COVID-19 patients, prevalence of ACI [38%vs5.9%], CA [26%vs5.3%], DIC [4%vs0.74%], septic shock [18%vs0.36%], and infection [30%vs12.5%] was higher among patients with poor outcomes. In meta-analysis, ACI [aOR:9.93(95%CI:3.95–25.00], CA [7.52(3.29–17.18)], DIC [7.36(1.24–43.73)], septic shock [30.12(7.56–120.10)], and infection [10.41(4.47–24.27)] had higher odds of adverse outcomes. Patients hospitalized with acute ischemic stroke and intracerebral hemorrhage, had complications like pulmonary embolism, venous thromboembolism, DIC, etc. and had poor outcomesConclusionThe complications like acute cardiac injury, cardiac arrhythmias, DIC, septic shock, and secondary infection had poor outcomes. Patients with stroke were having history of these complications. Long term monitoring is required in such patients to prevent stroke and mitigate adverse outcomes.  相似文献   
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Background/Aim:

Previous studies have shown the association of some genetic factors, such as Plasminogen activator inhibitor type-1 (PAI-1) 4G/5G polymorphism, with the development of inflammatory bowel disease (IBD). We aimed to study this polymorphism as a risk factor in IBD patients in this cohort.

Patients and Methods:

One hundred and fifteen IBD patients and 95 healthy controls were selected from Iranian Azeri Turks and -6754G/5G polymorphism of PAI-1 gene was tested by polymerase chain reaction using allele-specific primers confirmed by sequencing.

Results:

There was no significant difference of PAI-1 polymorphism between IBD patients and the control group (P > 0.05). Furthermore, these data showed no significant difference between Crohn''s disease and ulcerative colitis patients. However, 4G/4G homozygotes have reduced probability to progression of loss of appetite, whereas 5G/5G genotypes have increased risk for development of chronic diarrhea without blood, nausea, and loss of appetite.

Conclusions:

Although our study showed no significant association of PAI-1 polymorphism between patients and control group, the carriers of 4G/4G genotype and 4G allele had reduced risk for the progression of IBD features in this cohort.  相似文献   
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Objective: There is a promising perspective regarding the potential effect of resveratrol in preventing and treating metabolic disturbances similar to that of calorie restriction. The aim of this study was to evaluate the effects of calorie-restricted (CR) diet on metabolic parameters and then to investigate whether resveratrol supplementation has beneficial effects similar to CR diet in patients with nonalcoholic fatty liver disease (NAFLD).

Methods: This randomized controlled clinical trial was conducted in 90 patients with NAFLD (males and females) aged 20 to 60 years with body mass index (BMI) ranging from 25 to 35 kg/m2. Participants were assigned to one of three intervention groups as follows: The CR diet group (n = 30) received a prescribed low-calorie diet, the resveratrol group (n = 30) received 600 mg pure trans-resveratrol (2 × 300 mg) daily, and the placebo group (n = 30) received placebo capsules (2 × 300 mg) daily for 12 weeks. Fasting blood samples, anthropometric measurements, and dietary intake and physical activity data were collected for all participants at baseline and at the end of the trial.

Results: CR diet significantly reduced weight (by 4.5%); BMI; waist circumference; waist-to-hip ratio; and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lipid profiles in participants compared to resveratrol and placebo (all p < 0.05). Significant reductions in weight (by 1.1%) and BMI were found in the resveratrol group compared to the placebo group (p < 0.05). ALT, AST, and lipid profiles did not change significantly in the resveratrol group (all p > 0.05). No significant changes were seen in hepatic steatosis grade, serum glycemic parameters, and high-density lipoprotein cholesterol and sirtuin-1 levels in any group (all p > 0.05).

Conclusions: CR diet with moderate weight loss has favorable effects on NAFLD, and resveratrol supplementation induced weight loss but failed to mimic other aspects of CR diet. Future studies are warranted to evaluate the long-term and dose-dependent effects of resveratrol on metabolic diseases.  相似文献   

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As some breast cancer‐related deaths can be attributed to the metastasis of cancer stem cells, chemotherapeutic agents targeting breast cancer stem cells are of interest as a potential treatment. Flavonoids that exhibit cytotoxicity on breast cancer stem cells have rarely been observed. Thus, the objective of this study was to measure potential cytotoxic effects of 42 different flavonoids on the human breast cancer stem‐like cell line, MCF7‐SC. The relationship between flavonoid structural properties and cytotoxicity has not been reported previously; therefore, we determined quantitative structure–activity relationships using both comparative molecular field analysis and comparative molecular similarity analysis. Further biological experiments including Western blot analysis, flow cytometry, and immunofluorescence microscopy were also conducted on the most cytotoxic 8‐chloroflavanone.  相似文献   
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