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1.
BACKGROUND: Normal endothelial function depends on nitric oxide (NO) release by endothelial cells. Asymmetric dimethylarginine (ADMA), by competing with L-arginine, inhibits NO production and may lead to endothelial dysfunction and atherosclerotic development. Our aim was to ascertain the association between ADMA and coronary artery calcification (CAC), a marker of atherosclerotic coronary disease burden. DESIGN: A nested case-control study within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, an observational study among young adults residing in four US cities. METHODS: Participants were 263 white and black male and female cases with the presence of CAC and 263 sex and race-matched controls without evidence of CAC by computed tomography, 33-47 years old in 2000-2001. RESULTS: The median level (range) of ADMA was significantly higher in cases (0.55; 0.20-2.22 micromol/l) than in controls (0.53; 0.32-1.30 micromol/l; P=0.03). In conditional logistic regression adjusting for age, field center, educational attainment, smoking status, alcohol consumption, body mass index, waist circumference, hypertension, diabetes, low-density lipoprotein and high-density lipoprotein-cholesterol, triglycerides, renal function and C-reactive protein, the highest tertile of ADMA, compared with the lowest tertile, was associated with 1.80 (95% confidence interval 1.03-3.15) increased odds of the presence of any CAC. By linear regression, a significant independent relationship was also found between ADMA and the degree of CAC. CONCLUSION: These results support a role for ADMA as a biochemical marker of CAC.  相似文献   
2.
Upper abdominal surgery has a high incidence of postoperative respiratory complications. Although operations involving a thoracic as well as an upper abdominal incision as encountered in esophageal surgery are likely to be associated with an even higher complication rate and perhaps permanent alterations of respiratory function, only a few studies have addressed this problem. We evaluated the postoperative course of patients undergoing thoracoabdominal esophagectomy with esophagogastrostomy. Twenty patients were evaluated, of whom 10 (50%) developed respiratory complications as defined by our criteria, which were the simultaneous occurrence of rectal temperature over 38 degrees C on the first postoperative day and radiographic evidence of pulmonary infiltration. Although there is no general consensus regarding the diagnostic criteria of a postoperative pulmonary complication, we were able to validate the clinical relevance of our definition by showing that these patients suffered from a more severe and more prolonged impairment of global oxygen exchange than those who did not fulfill the criteria. They also required a longer period of respiratory support (median duration of intubation 12 vs. 3 days, P less than 0.005). A comparison of the preoperative pulmonary function with that determined at least 6 months after the operation showed that only vital capacity (VC) and total lung capacity (TLC) were significantly (P less than 0.05) reduced following the operation, but not to a clinically relevant degree (VC-6%, TLC-7%).  相似文献   
3.
Forty-nine patients were treated with either 3×75 MBq 89Sr or saline as placebo. Analysis of results 1 to 3 years after therapy revealed the ineffectiveness of 89Sr to relieve pain from metastases. Unexpectedly, a higher survival rate was found after Sr application (46% vs 4% after 2 years). Covariate analysis underlines the effect of 89Sr therapy on life expectation.  相似文献   
4.
Two partially overlapping 19 and 22 amino acids long peptides representing a highly immunogenic site of the transmembranous glycoprotein (gp41) of human immunodeficiency virus (HIV) were used as antigen in ELISA tests. The results of antibody determination with this assay were compared with those of three or more conventional ELISAs and Western blot (WB) tests and radioimmunoprecipitation assay. Twenty-six sera from patients with AIDS or LAS and from asymptomatic carriers of HIV infection all showed a pronounced reaction in the peptide ELISA as well as positive results with other tests. In contrast, 27 sera from laboratory workers and blood donors were negative by all tests. A group of 39 blood donor sera, which had shown false positive or ambiguous results in the ELISAs and sometimes in WB tests employed for confirmation, also were negative in all cases with the peptide ELISA. Consecutive samples collected from individuals with primary HIV infection were also analyzed. In 6 out of 9 cases, the peptide ELISA revealed an antibody response within one month after onset of clinical symptoms and sensitivity for antibody detection equaled that of other ELISA tests. Eight sera from five West African persons infected with HIV-related viruses did not react in the peptide ELISA, reflecting differences in properties of the envelope components. The peptide ELISA used in this study appears to represent a simple technique employing chemically synthesized antigen for accurate and sensitive estimation of antibodies to the HIV group of nontransforming human retroviruses.  相似文献   
5.
Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.  相似文献   
6.
In previous studies of schizophrenic patients, neuromuscular (histopathological and electrophysiological) and psychomotor (finger tapping) abnormalities were found. The present study was designed to investigate relationships between these abnormalities and a family history of psychosis in 14 schizophrenic patients and 25 unaffected first-degree relatives compared to 14 healthy controls. Muscle biopsies were performed in either m. tibialis anterior or m. lateralis. Macro EMG recordings were made from m. tibialis anterior. A finger tapping test was used to investigate psychomotor performance. Neuromuscular abnormalities (muscle biopsies and/or macro EMG) and/or aberrant psychomotor performance (finger tapping test) were found in 13 (93%) patients, 14 (56%) first-degree relatives and in three (21%) controls. A statistically significant relationship for the psychomotor, but not neuromuscular changes to a family history of psychosis was found using a logistic regression method. The percentage of patients, relatives and healthy controls exhibiting were 36/40/7% in the muscle biopsy, 50/20/0% in the macro EMG, and 71/82/14% in the finger tapping investigations. A higher frequency of neuromuscular and psychomotor abnormalities was found in patients with schizophrenia and their first-degree relatives compared to healthy controls. The relationship between psychomotor findings and a family history of psychosis indicate that central aspects of motor aberrations are associated with a hereditary disposition of psychosis. The neuromuscular as well as psychomotor changes indicate that schizophrenia may be a systemic disease involving the central nervous system as well as peripheral organs. An altered cell membrane is suggested to be an underlying factor based on the type of neuromuscular findings.  相似文献   
7.
Hyperhomocysteinemia is associated with an enhanced risk for cardiovascular disease. Patients with peripheral arterial disease (PAD) show an increased prevalence of hyperhomocysteinemia. A decreased biological activity of nitric oxide (NO) may contribute to homocysteine-associated endothelial dysfunction. This study was designed to investigate whether elevated levels of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA) are involved in endothelial dysfunction in patients with chronic hyperhomocysteinemia and PAD. A total of 76 patients (58 males and 18 females; mean age 65.2 +/- 2.0 years) with PAD were included in the analysis and characterized according to demographic variables and cardiovascular risk factors. Flow-dependent vasodilation (FDD) was determined by high-resolution ultrasound in the radial artery. Total plasma homocysteine (plasma tHcy) and ADMA levels were measured by HPLC. Urinary nitrate was quantified using gas chromatography-mass spectrometry. Patients with plasma tHcy in the highest tertile (n = 27; i.e. > 10.6 micromol/l) had a mean plasma level of 14.4 +/- 1.21 mol/l compared with 9.9 +/- 0.1 micromol/l in those patients in the middle tertile (n = 22; p < 0.05) and 9.4 +/- 0.1 micromol/l in those in the lowest tertile (n = 27; i.e. <9.6 micromol/l; p < 0.05). The hyperhomocysteinemic individuals (highest tertile) had a significantly decreased FDD compared with healthy age-matched controls (n = 15) (7.6 +/- 1.0 vs 13.0 +/- 0.4%; p < 0.05), higher plasma ADMA concentrations (4.0 +/- 0.3 vs 2.6 +/- 0.3 micromol/l; p < 0.05), and a lower urinary nitrate excretion rate (89.5 +/- 13.4 vs 131.3 +/- 17.9 micromol/mmol creatinine; p < 0.05) compared with patients with plasma tHcy in the lowest tertile. Multivariate regression analysis including plasma tHcy, ADMA, total cholesterol, diabetes mellitus, smoking, and systolic blood pressure revealed ADMA as the only significant factor determining FDD (p < 0.05). In conclusion, we demonstrated a stronger relationship between impaired endothelial function and elevated ADMA levels in comparison with plasma tHcy concentrations in patients with PAD and chronic hyperhomocysteinemia. This may raise the question of whether different therapeutical options that interact indirectly with plasma tHcy, i.e. treatment with ACE inhibitors and AT1-receptor blockers to reduce ADMA plasma concentrations or L-arginine, could be a beneficial tool for treating patients with hyperhomocysteinemia.  相似文献   
8.
9.
V Wunderlich  F Fey  G Sydow 《Neoplasma》1987,34(4):389-396
Haloperidol, a butyrophenon, is widely used for the treatment of psychotic disorders in man. Recently we reported that this drug causes, with high incidence, the development of monocytic-myeloid leukemias in male NMRI mice upon 5 X 5 mg/kg i.p. administration. Here we present evidence for the leukemogenic effect of haloperidol in two other strains of mice (XVII AKF1 hybrids, and the low leukemic BALB/c/BOM). The strain-dependent incidence of leukemias ranged both in males and females between 34% (AKR) and 69% (XVII AKF1) with average latencies between approximately 200 (AKR) and 600 (BALB/c) days. On the basis of cytological and cytochemical criteria the predominating type of leukemias was classified as monocytic-myeloid. These leukemic were serially transplantable. Cell-free extracts of leukemic tissues did not induce the disease indicating that no virus was activated by haloperidol. However, when the drug was administered to AKR mice after a suboptimal dose of nitrosomethylurea (NMU), a higher incidence of mixed-type leukemias was observed as with haloperidol alone. NMU alone induced lymphatic leukemias with proven viral involvement. The tumor promoter 12-0-tetradecanoylphorbol-13-acetate did not influence haloperidol-induced leukemogenesis.  相似文献   
10.
Summary Seventy-four patients in 1978 and 316 in 1986, all transfused during open-heart surgery in Stockholm, Sweden, were studied prospectively for the development of posttransfusion non-A, non-B (NANB) hepatitis, seroconversion to hepatitis C virus antibodies (anti-HCV) (C-100), time lag to seroconversion to anti-HCV and outcome of posttransfusion NANB/C hepatitis. Anti-HCV was tested up to six months after transfusions in patients from 1978 and up to one year after transfusions in patients from 1986. Fifty-four percent of the patients who developed posttransfusion NANB hepatitis seroconverted to anti-HCV, 7/15 (47%) in 1978 and 8/13 (62%) in 1986. Four (27%) of the 15 patients who seroconverted to anti-HCV were anti-HCV reactive within one week, 12 (80%) within eight weeks and all within 18 weeks after the onset of hepatitis. The ELISA optical density/cut-off (OD/CO) ratio was above 4.0 in all patients with hepatitis C who seroconverted. One transfused patient with normal serum aminotransferase levels throughout follow-up seroconverted after six months. He had a temporary positive anti-HCV reactivity with a maximal ELISA OD/CO ratio for anti-HCV of only 1.2, which became negative three years later. Development of chronic hepatitis was noticed in 9/15 (60%) patients who seroconverted to anti-HCV and in 5/13 (38%) patients with posttransfusion NANB hepatitis who did not seroconvert.
Anti-HBC-Serokonversion bei Patienten mit akuter Non-A, Non-B-Hepatitis nach Transfusion in Schweden
Zusammenfassung 74 Patienten, die 1978, und 316 Patienten, die 1986 während offener Herzchirurgie in Stockholm, Schweden, Transfusionen erhielten, wurden in eine prospektive Studie aufgenommen und im Hinblick auf das Auftreten einer Non-A, Non-B-Posttransfusions-hepatitis, Serokonversion für Hepatitis C Virus-Antikörper (anti-HCV, C-100), Zeitspanne bis zur Serokonversion für anti-HCV und Verlauf der NANB/C-Posttransfusionshepatitis untersucht. Bei Patienten, die 1978 transfundiert worden waren, wurden Untersuchungen auf anti-HCV bis zu sechs Monate nach der Transfusion und bei 1986 Transfundierten bis zu einem Jahr nach Transfusion durchgeführt. Eine Serokonversion zu anti-HCV trat bei 54% der Patienten mit NANB-Posttransfusions-hepatitis ein, 7/15 (47%) der Patienten aus dem Jahr 1978 und 8/13 (62%) aus dem Jahr 1986. Die Serokonversion zu anti-HCV trat bei vier der 15 Patienten (27%) schon innerhalb einer Woche ein, bei 12 (80%) innerhalb acht Wochen und bei allen innerhalb 18 Wochen nach Beginn der Hepatitis. Bei den Patienten mit Hepatitis C, die eine Serokonversion entwickelten, lag der Quotient von ELISA Meßwert zu Grenzwert (Optical density/ Cut-off, OD/CO) in allen Fällen über 4,0. Ein Patient, bei dem nach der Transfusion stets normale Serum- Aminotransferase-Spiegel vorlagen, zeigte nach sechs Monaten eine Serokonversion. Er war vorübergehend anti-HCV positiv, der ELISA OD/CO- Quotient für anti-HCV betrug maximal 1,2; nach drei Jahren war er seronegativ. Bei neun der 15 Patienten (60%) war eine chronische Hepatitis nach Serokonversion für anti-HCV zu beobachten. Unter den 13 Patienten mit NANB-Posttransfusionshepatitis, die keine Serokonversion zeigten, entwickelten fünf eine chronische Hepatitis (38%).
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