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121.
Endothelin has been identified as a potent vasoconstrictor. The aim of this study was to evaluate urinary endothelins and their relation to other markers of renal damage, such as microalbuminuria, creatinine, and N-acetyl-beta-glucosaminidase (NAG), in a group of recently diagnosed (less than 1 year) hypertensive subjects and a control group. We selected 50 subjects and divided them into two groups: 27 hypertensive patients (15 females and 12 males) without previous pharmacologic therapy, and 23 healthy, normotensive subjects (12 females and 11 males). All patients underwent a history and physical examination, chest x-ray, electrocardiography, funduscopy, and hematologic and biochemical analyses. Endothelins, microalbuminuria, creatinine, and NAG values were also determined in 24-hour urine samples. Creatinine, microalbuminuria, and NAG values were found to be higher in hypertensive than in normotensive subjects. The hypertensive group showed a nonsignificant elevation of total endothelin. In conclusion, the determination of elevated urinary endothelin does not appear to be an early marker of organ damage in hypertensive subjects. The urinary excretion of protein, creatinine, and NAG was higher in hypertensive subjects. A positive correlation was found between the urinary excretion of endothelins and markers of renal damage, microalbuminuria and NAG values. The relationship between endothelins and hypertension was without statistical significance.  相似文献   
122.
OBJECTIVE: It has been suggested that genotypic variation in the gene which encodes the matrilin-1 (MATN-1) protein may be involved in the development of hip osteoarthritis (OA). We compared genotype frequencies of the MATN-1 gene (1p35) in patients with OA and controls to determine if there is any association between the MATN-1 genotype and OA. METHODS: 73 OA patients and 53 controls from a rheumatology ambulatory center and a university hospital were studied. They were unrelated subjects. Controls were free of clinical OA. OA was defined according to the American College of Rheumatology criteria. The MATN-1 microsatellite in the 3'untranslated region was amplified by PCR. The size of the amplification products was determined by capilar electrophoresis in a DNA Genetic Analizer Genotypic distribution was compared by the chi2 test. RESULTS: We identified 4 alleles according to their basepair (bp) length: A1 = 110 bp; A2 = 108 bp; A3 = 106 bp and A6 = 104 pb. Six genotypes were found, with an observed heterozygosity of 0.48. The most frequent genotype in OA and controls was A1/A1 (43.8% and 43.4%, respectively). No significant difference in genotype distribution was found between OA - even when discriminating by the affected joint - and controls. CONCLUSION: We did not find any difference in the MATN-1 genotype distribution in OA patients and controls. To our knowledge, this would be the first time a MATN-1 allele of 104 bp (A6) has been identified These results do not support a role of the MATN-1 genotypes in the occurrence of clinical OA.  相似文献   
123.
OBJECTIVE: We developed a rodent model of noninfectious systemic inflammation to examine the pathogenesis of the associated anemia of chronic disorders (ACD), to evaluate the similarity of this ACD model to human ACD, and to evaluate the potential efficacy of novel erythropoiesis stimulating protein (darbepoetin alfa) as an ACD therapy. METHODS: Lewis rats were immunized with peptidoglycan-polysaccharide polymers (PG-APS), the chronic inflammation and associated ACD were characterized, and the effects of darbepoetin alfa treatment on complete blood counts (CBC), red blood cell (RBC) indices, and iron metabolism were analyzed weekly. RESULTS: Acutely inflamed rats had reduced peripheral blood (PB) RBC counts and hemoglobin (Hb) concentrations and increased reticulocyte counts. PB RBC numbers normalized during chronic inflammation, but RBC remained hypochromic and microcytic. Consequently, the rats remained chronically anemic. Anemic rats had fluctuating serum erythropoietin (EPO) concentrations, but mean EPO concentrations never varied significantly from baseline control levels. Histology of anemic rat spleen sections revealed reticuloendothelial siderosis. Total serum iron concentrations were chronically low. Peritoneal exudate cells (PEC) isolated from anemic rats and stimulated with PG-APS in vitro produced more interleukin (IL)-1alpha and interferon (IFN)-gamma, and significantly more tumor necrosis factor (TNF)-alpha and IL-10 than control cultures. Darbepoetin alfa restored Hb concentrations to baseline levels within 2 to 7 weeks, depending on dosage. A refined treatment strategy restored Hb to baseline and maintained those levels with reduced dosing. CONCLUSION: ACD in this rodent model closely replicates human ACD. Darbepoetin alfa treatment reversed ACD in this model by increasing RBC production and RBC hemoglobinization while reducing siderosis and hypoferremia.  相似文献   
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Summary The present study was aimed at determining the generation of prostacyclin (PGI2)-like-material in coronary arteries from normal and diabetic (pancreatectomized) dogs as well as the contractile responses to prostacyclin of preparations from normal, diabetic and insulin-treated diabetic animals. PGI2 produced a dose-dependent relaxation of coronary arteries from normal dogs. In contrast, those from diabetic animals were not relaxed; indeed, at low concentrations PGI2 failed to evoke any effect but at higher ones it induced a distinct contraction. In arteries from diabetic animals treated with insulin, PGI2 induced a biphasic contractile effect, which lay between that of normal controls and untreated diabetics. In addition the basal generation of PGI2-like-material by coronary arteries was significantly higher in the diabetic (141±0.2 pg/mg, mean±SEM) than in normal dogs (59±0.2 pg/mg). The present experiments demonstrate that the generation of PGI2-like-substance is significantly increased in coronary arteries from diabetic dogs, but the same vessels are unable to respond to added authentic PGI2 with relaxation; on the contrary they react with a distinct positive contractile response.  相似文献   
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128.

Introduction

Interstitial lung diseases (ILD) and, in particular, idiopathic pulmonary fibrosis, may have a significant impact on patient survival. Recent studies highlight the need for palliative care (PC) in the management of ILD patients. The aim of this study was to determine the current situation of PC in patients in Spain.

Methods

A 36-question survey addressing the main aspects of PC in ILD patients was designed. The survey was sent via email to all members of the Spanish Society of Pulmonology and Thoracic Surgery. Participation was voluntary.

Results

One hundred and sixty-four participants responded to the survey. Ninety-eight percent said they were interested in PC, 46% had received specific training, and 44% reported being responsible for PC in their ILD patients. Symptom control and end-of-life stage were the most frequent reasons for referral to PC teams. Regarding end-of-life, 78% reported consensual agreement with patients on the limitation of therapeutic efforts, 35% helped prepare an end-of-life advance directive, and 22% agreed on the place of death.

Conclusion

Despite the well-known need for PC in patients with ILD and the notable interest of the survey participants in this subject, there are clear formative and organizational gaps that should be addressed to improve care in this area in ILD patients in Spain.  相似文献   
129.
Hepatitis B virus DNA (HBV-DNA) in serum was studied in 67 anti-HBe patients using dot-blot hybridization, a modified technique and polymerase chain reaction (PCR). All patients had abnormal aminotransferase (ALT) levels. Serum HBV-DNA was detected in 14/67 cases by dot-blot and in 39/67 (DNA probe) and 45/67 (RNA probe) using the modified technique. The RNA probe was more sensitive than the DNA probe when they were compared, using serial dilutions of HBV-DNA of known concentration (0.1 pg vs 1 pg, respectively). HBV-DNA was found by PCR in 57/67 patients. Ten patients were negative to serum HBV-DNA. The ALT level was significantly higher in patients with serum HBV-DNA by dot-blot as compared to those who had serum HBV-DNA by the modified technique and PCR. With respect to the presence of anti-HCV, 6/67 had anti-HCV confirmed by RIBA test. These 6 patients had serum HBV-DNA. The route of acquisition of HBV infection in anti-HCV positive patients was by parenteral exposure in 67% of the cases and 15% in HCV negative (p less than 0.05). All patients were negative to nonorganic specific autoantibodies. In summary, most of the anti-HBe patients (85%) had viral replication. HCV superinfection plays a minor role in the activity of liver disease.  相似文献   
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