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91.
OBJECTIVES: In the present study, we use valsartan, a highly selective antagonist for angiotensin(1) (AT(1)) receptor subtype, to investigate the effect of AT(1) receptor on the plasma glucose metabolism in streptozotocin-induced diabetic rats (STZ-diabetic rats). METHODS: The plasma glucose concentration was assessed by glucose oxidase method and plasma insulin was measured using enzyme-linked immunosorbent assay. Systolic blood pressure (SBP) was determined by the tail-cuff method. The intravenous glucose challenge test (IVGCT) was carried out to evaluate the effect of valsartan on the glucose utilization in vivo. The mRNA levels of the subtype 4 form of glucose transporter (GLUT4) in soleus muscle and phosphoenolpyruvate carboxykinase (PEPCK) in the liver were detected by Northern blotting analysis. Moreover, the protein levels of GLUT4 in isolated soleus muscle and hepatic PEPCK were investigated using Western blotting analysis. RESULTS: A single intravenous injection of valsartan decreased the plasma glucose concentrations in a dose-dependent manner in STZ-diabetic rats. Plasma glucose-lowering action of valsartan also observed in normal rats although in a way not so effective as that in STZ-diabetic rats. Valsartan at the dose of 0.2 mg/kg that produced the maximal plasma glucose-lowering activity in STZ-diabetic rats is also effective to lower the SBP. However, oral treatment with nifedipine or nicorandil in STZ-diabetic rats at the dose sufficient to decrease SBP showed no change of plasma glucose. Otherwise, infusion of saralasin (10 microg/kg per min) into STZ-diabetic rats produced a plasma glucose-lowering activity similar to that by valsartan at 0.2 mg/kg. Moreover, valsartan (0.2 mg/kg) significantly attenuated the raise of plasma glucose induced by IVGCT in normal rats. Repeated intravenous administration of valsartan (0.2 mg/kg) in STZ-diabetic rats resulted in the lowering of plasma glucose after 3 days. The mRNA and protein levels of GLUT4 in the soleus muscle were increased after repeated intravenous administration of valsartan in STZ-diabetic rats for 3 days. Moreover, similar repeated treatment with valsartan reversed the elevated mRNA and protein levels of PEPCK in the liver of STZ-diabetic rats. CONCLUSIONS: These results suggest that the plasma glucose-lowering activity of AT(1) receptor antagonism was associated with an increase in the glucose utilization in peripheral tissue and/or a reduction in hepatic gluconeogenesis in the absence of insulin.  相似文献   
92.
BACKGROUND/PURPOSE: Cervical cancer remains a health problem among women worldwide. Delineation of genetic changes is critical to understanding the molecular basis of tumor progression, as well as for identifying genetic markers for early identification of patients at high risk for a poor outcome. METHODS: To provide comparative genomic hybridization data for cervical squamous cell carcinoma in Taiwan, and to gain further insight into genetic markers associated with lymph node metastasis of this disease, we performed comparative genomic hybridization analysis of 30 consecutive cases of cervical squamous cell carcinoma (24 stage IB and 6 stage IIB). RESULTS: The results disclosed that higher staged tumors or those with lymph node metastasis had more chromosomal imbalances. The commonly recurrent chromosomal imbalances were gains of 3q (46.7%), 1q (36.7%) and 8q (20.0%) and losses of 11q (36.7%), 3p (33.3%), 6q (23.3%), and 2q (20.0%). The frequencies of these chromosomal imbalances in stage IB and IIB tumors did not differ significantly. However, when compared with tumors without lymph node metastasis, the loss of 11q14-q22 (5/9 vs. 3/21, p = 0.019) and gains of 3q11-q22 and 3q26-qter (6/9 vs. 5/21, p = 0.026) were significantly more prevalent in tumors with lymph node metastasis. CONCLUSION: The results suggest that certain tumor-associated genes residing on 3q and 11q warrant further investigation to elucidate their role in the progression of this disease.  相似文献   
93.
The ABO blood group system is the most important blood group system in transfusion medicine. In addition to the major A, B and O alleles, many rare alleles with weak expression of the A or B antigens on RBCs have been defined. We report here the molecular analysis of a novel A(el) allele. Exons 6 and 7 of the ABO gene were PCR-amplified, cloned and sequenced for the propositus, Mr C, who is a 56-year-old Taiwanese male and was incidentally observed to have an A(el) phenotype. His direct family members including wife, son and daughter were subsequently enrolled for further study. Three hundred random blood donors of AB phenotype served as control. A novel A(el) allele was uncovered from the propositus and his daughter, of which a unique 816insG mutation occurred on the A102 background that results in a frame shift leading to a 37-amino acid longer polypeptide than the normal A1 transferase, a finding similar to that of Ael01 allele with 804insG. We found that the C family carried a novel A(el) allele that differs molecularly from seven A(el) alleles reported in the literature.  相似文献   
94.
Inducible nitric oxide synthase and vascular injury   总被引:16,自引:0,他引:16  
The role nitric oxide (NO) plays in the cardiovascular system is complex and diverse. Even more controversial is the role that the inducible NO synthase enzyme (iNOS) serves in mediating different aspects of cardiovascular pathophysiology. Following arterial injury, NO has been shown to serve many vasoprotective roles, including inhibition of platelet aggregation and adherence to the site of injury, inhibition of leukocyte adherence, inhibition of vascular smooth muscle cell (VSMC) proliferation and migration, and stimulation of endothelial cell (EC) growth. These properties function together to preserve a normal vascular environment following injury. In this review, we discuss what is known about the involvement of iNOS in the vascular injury response. Additionally, we discuss the beneficial role of iNOS gene transfer to the vasculature in preventing the development of neointimal thickening. Lastly, the pathophysiology of transplant vasculopathy is discussed as well as the role of iNOS in this setting.  相似文献   
95.
Purple urine bag syndrome (PUBS) is a rare occurrence, in which the patient has a purple-colored urine bag following urinary catheterization for hours to days. Most of authors believe it is a mixture of indigo (blue) and indirubin (red) that becomes purple. Previous study showed that PUBS occurred predominantly in chronically catheterized, constipated women. We collected 10 elderly patients with PUBS in two nursing homes. The first two cases were identified by chart review in 1987 and 2003, and then later eight cases (42.1%) were collected among 19 urinary catheterized elderly in the period between January 2007 and June 2007. In the present report, PUBS probably can occur in any patients with the right elements, namely urinary tract infection (UTI) with bacteria possessing these enzymes, diet with enough tryptophan, and being catheterized. Associations with bed-bound state, Alzheimer’s, or dementia from other causes are reflections of the state of such patients who are at higher risk for UTI, and hence PUBS occurred. Although we presented PUBS as a harmless problem, prevention and control of the nosocomial catheter-associated UTIs (CAUTIs) has become very important in the new patient-centered medical era. Thus, we should decrease the duration of catheterization, improve catheter care, and deploy technological advances designed for prevention, especially in the elderly cared for in nursing homes.  相似文献   
96.
PURPOSE: The purpose was to investigate the contributing factors of practicing religious activities (prayer and attending religious services) that help in overcoming the health problems that had led to the current hospitalization. These activities may be a proxy measure for religious coping with health problems. DESIGN: An exploratory survey study was used. METHODS: A convenience sample was determined. Data were collected in 2005 in the inpatient wards of a Taiwanese hospital (n = 1,031 patients and family visitors). Binary logistic regression analyses were used. FINDINGS: Of the participants, 75% offered prayer to their god(s) for help and 57.4% attended a church/temple service. Being a patient and having a longer hospital stay contributed to the increased probability of offering prayer and attending religious services. CONCLUSIONS: Prayer and religious service attendance were practiced by the majority of those hospitalized patients and their family. Enriching our understanding of the religious needs of the patients and their family should be continued.  相似文献   
97.
Improving health standards both nationally and cross-culturally is a goal for all community health nurses. Previous research has supported links between health attitudes and behavior. The purpose of the present study was to investigate the relationship between attitudes toward health and indexes of community health using a cross-cultural data set. Concepts selected from the data set were I (myself), body, sickness, disease, life, doctor, health, medicine, hospital, nurse, death, and insane. Community health indicators were male and female life expectancy, infant mortality, economic and public health expenditures, and net social progress. The original sample included 1200 high school males within each of 30 language and cultural communities. Data were derived from students' ratings of the dimensions of evaluation, potency, and activity for each concept. The results supported the association between attitudes and objective community health indicators. Unexpected negative correlations were found between attitudes toward medicine and nurse attitudes toward body and life, perhaps indicating that extended contact with health care providers may result in negative attitudes toward them. Positive relationships were found between public health expenditures and nurses, indicating that in countries with more expenditures for community and public health, attitudes toward nurses were more positive.  相似文献   
98.
Monoclonal antibodies against Trichomonas vaginalis   总被引:1,自引:0,他引:1  
Spleen lymphocytes obtained from mice immunized with Trichomonas vaginalis ATCC 30001 were fused with P3-X63-Ag8-653 mouse myeloma in order to produce hybridoma-secreting antibodies against T. vaginalis associated antigens. Six hybridoma cloned cell lines were established; three produced IgG1, two produced IgG2a, and one produced IgM monoclonal antibody. These six monoclonal antibodies showed binding to seven isolated strains of T. vaginalis but did not bind to Giardia lamblia. Three of those monoclonal antibodies did not bind to Tritrichomonas foetus. These anti-trichomonal monoclonal antibodies should prove to be of great value as diagnostic and research reagents.  相似文献   
99.
Inhibition of platelet aggregation by some flavonoids.   总被引:14,自引:1,他引:13  
The inhibitory effects of five flavonoids on the aggregation and secretion of platelets were studied. These flavonoids inhibited markedly platelet aggregation and ATP release of rabbit platelets induced by arachidonic acid or collagen, and slightly those by platelet-activating factor. ADP-induced platelet aggregation was also suppressed by myricetin, fisetin and quercetin. The IC50 on arachidonic acid-induced platelet aggregation was: fisetin, 22 microM; kaempferol, 20 microM; quercetin, 13 microM; morin, 150 microM less than IC50 less than 300 microM. The thromboxane B2 formations were also inhibited by flavonoids in platelets challenged with arachidonic acid. Fisetin, kaempferol, morin and quercetin antagonized the aggregation of washed platelets induced by U46619, a thromboxane A2/prostaglandin endoperoxides mimetic receptor agonist. In human platelet-rich plasma, quercetin prevented the secondary aggregation and blocked ATP release from platelets induced by epinephrine or ADP. These results demonstrate that the major antiplatelet effect of flavonoids tested may be due to both the inhibition of thromboxane formation and thromboxane receptor antagonism.  相似文献   
100.
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