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11.
12.
The metabolic syndrome among postmenopausal women in Ecuador.   总被引:1,自引:0,他引:1  
BACKGROUND: The prevalence of the metabolic syndrome increases with age and after the onset of menopause, and may explain in part the apparent acceleration of cardiovascular disease in postmenopausal women. OBJECTIVE: To determine the prevalence of metabolic syndrome and related risk determinants among postmenopausal women in Ecuador. METHODS: Postmenopausal women >or=40 years of age, non-users of hormone therapy and with an intact uterus, were asked to participate in a metabolic syndrome screening and educational program at the Institute of Biomedicine of the Universidad Católica of Guayaquil, Ecuador. Sociodemographic data, waist circumference and blood pressure measurements were recorded, and a fasting blood sample obtained for serum glucose and lipid profile determinations. Woman were counseled and managed according to the results. Metabolic syndrome was defined in accordance with the criteria of the Third Adult Treatment Panel (ATP III). RESULTS: Three hundred and twenty-five postmenopausal women entered the program. Mean (+/-standard deviation) age was 55.9 +/- 8.1 years, 53.5% of them were aged >or=54 years (median). The prevalence of metabolic syndrome, according to ATP III criteria, was 41.5%. Using the same criteria, 38.8%, 16.6%, 56.9% and 54.2% of the women presented with hypertension, diabetes, hypertriglyceridemia and abdominal obesity, respectively. More than 40% of women determined to have hypertension or diabetes lacked knowing so. Logistic regression analysis determined that age increased the risk of presenting hypertension and diabetes (odds ratio (95% confidence interval): 2.0 (1.2-3.2) and 1.6 (0.9-3.0), respectively, p < 0.05), entities which in turn duplicated the risk of having high triglyceride levels. Sedentary women with <5 years since menopause onset were at higher risk of having abdominal obesity, which was directly related to diabetes and hypertension. CONCLUSIONS: In this postmenopausal Ecuadorian population the prevalence of the metabolic syndrome was high and its determinant factors related to age, time since menopause onset and sedentary habits. Because of the implications for cardiovascular risk, counseling programs directed toward high-risk populations should be encouraged.  相似文献   
13.
The furin cleavage site (FCS), an unusual feature in the SARS-CoV-2 spike protein, has been spotlighted as a factor key to facilitating infection and pathogenesis by increasing spike processing. Similarly, the QTQTN motif directly upstream of the FCS is also an unusual feature for group 2B coronaviruses (CoVs). The QTQTN deletion has consistently been observed in in vitro cultured virus stocks and some clinical isolates. To determine whether the QTQTN motif is critical to SARS-CoV-2 replication and pathogenesis, we generated a mutant deleting the QTQTN motif (ΔQTQTN). Here, we report that the QTQTN deletion attenuates viral replication in respiratory cells in vitro and attenuates disease in vivo. The deletion results in a shortened, more rigid peptide loop that contains the FCS and is less accessible to host proteases, such as TMPRSS2. Thus, the deletion reduced the efficiency of spike processing and attenuates SARS-CoV-2 infection. Importantly, the QTQTN motif also contains residues that are glycosylated, and disruption of its glycosylation also attenuates virus replication in a TMPRSS2-dependent manner. Together, our results reveal that three aspects of the S1/S2 cleavage site—the FCS, loop length, and glycosylation—are required for efficient SARS-CoV-2 replication and pathogenesis.

SARS-CoV-2 emerged in late 2019 and has caused the largest pandemic since the 1918 influenza outbreak (1). An unusual feature of SARS-CoV-2 is the presence of a furin cleavage site (FCS) in its spike protein (2). The CoV spike is a trimer of spike proteins composed of the S1 and S2 subunits, responsible for receptor binding and membrane fusion, respectively (1). After receptor binding, the spike protein is proteolytically cleaved at the S1/S2 and S2′ sites to activate the fusion machinery. For SARS-CoV-2, the spike protein contains a novel cleavage motif recognized by the host cell furin protease (PRRAR) directly upstream of the S1/S2 cleavage site that facilitates cleavage prior to virion release from the producer cell. This FCS, not found in other group 2B CoVs, plays a key role in spike processing, infectivity, and pathogenesis as shown by our group and others (3, 4).Importantly, another novel amino acid motif, QTQTN, is found directly upstream of the FCS. This QTQTN motif, also absent in other group 2B CoVs, is often deleted and has been pervasive in cultured virus stocks of the alpha, beta, and delta variants (58). In addition, the QTQTN deletion has been observed in a small subset of patient samples as well (911). Because this deletion has been frequently identified, we set out to characterize it and determine whether it has consequences for viral replication and virulence. Using our infectious clone (12, 13), we demonstrated that the loss of this motif attenuates SARS-CoV-2 replication in respiratory cells in vitro and pathogenesis in hamsters. The QTQTN deletion results in reduced spike cleavage and diminished capacity to use serine proteases on the cell surface for entry. Importantly, mutations of glycosylation-enabling residues in the QTQTN motif results in similar replication attenuation despite intact spike processing. Together, our results highlight elements in the SARS-CoV-2 spike in addition to the FCS that contribute to increased replication and pathogenesis.  相似文献   
14.
The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues.  相似文献   
15.
We used monospecific antibodies on semithin frozen sections to identify and localize the major tissue constituents of the nonglaucomatous human trabecular meshwork. The trabecular beams (sheets and cords) consist of a basement membrane (subendothelial extracellular matrix) surrounding an interstitial central core of connective tissue (substantia propria). The basement membrane contains collagen types III, IV, and V, the glycoproteins laminin and fibronectin, and the basement membrane-associated heparan sulfate proteoglycan. The trabecular basement membrane is unlike most subendothelial basement membranes because it contains collagen type III and a relatively disorganized structure. The central core contains collagen types I and III, and elastin. The closely linked juxtacanalicular meshwork contains collagen type III, but no collagen type I or elastin. The connective tissue composition of the trabecular meshwork appears similar to other highly compliant and resilient tissues, such as lung, blood vessels, and conjunctiva.  相似文献   
16.
Proton magnetic resonance spectroscopy (MRS) is a noninvasive method to assess concentrations of different metabolites in tissues, including the brain. We evaluated a fetus with growth restriction using Doppler ultrasound and proton MRS. Doppler assessment revealed absent end diastolic flow in the umbilical artery. Diastolic flow was increased in the middle cerebral artery. Proton MRS of the fetal brain showed lactate and a low N-acetylaspartate/choline index, metabolic markers of starvation/hypoxia. Proton MRS gave us in vivo metabolic information of the brain of a fetus under starvation/hypoxic conditions. It is potentially a new tool for fetal surveillance. To our knowledge, this is the first report of cerebral lactate detection using proton MRS in a growth-restricted human fetus with no associated malformations in the English literature. Further experimental and clinical longitudinal investigations are needed to evaluate its efficacy in the clinical setting.  相似文献   
17.
The Medical Association for Prevention of War (UK) submitted the following written statement to the Third Special Session on Disarmament of the United Nations General Assembly, which was held at UN headquarters in New York on 31 May‐25 June 1988.  相似文献   
18.
Homans  AC; Forman  EN; Barker  BE 《Blood》1985,66(6):1321-1325
The identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of children with acute lymphoblastic leukemia (ALL). We adapted a latex sphere rosetting technique to allow us to identify simultaneously cell surface markers and cell morphology in 199 CSF samples from 34 patients and 14 control subjects. In patients without leukemic meningitis, the majority of CSF lymphocytes (69%) were found to be mature T cells positive for OKT11. A much smaller number of cells (8%) were found to be B cells positive for la. In these children, only 3% of CSF lymphoid cells expressed the common acute lymphoblastic leukemia antigen (CALLA). Similar results were found in the control subjects. By contrast, 28 CSF samples from nine children with varying numbers of CSF lymphoblasts had much greater proportions of CALLA- and la-positive CSF cells (24% to 96%). Leukemic meningitis was present in one of these patients and later developed in four others. However, three patients with small numbers of lymphoblasts present but with low proportions of CALLA-positive CSF cells (less than 5%) subsequently had normal CSF examinations. We found the use of this rosetting technique valuable in providing information complementary to that obtained from cell morphology alone about the possible malignant nature of small numbers of lymphoblast-like CSF cells seen on cytocentrifuge preparations in children with ALL.  相似文献   
19.
Sequential contrast-enhanced MR imaging of the penis   总被引:1,自引:0,他引:1  
Kaneko  K; De Mouy  EH; Lee  BE 《Radiology》1994,191(1):75
  相似文献   
20.
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