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2.
AIMS: To evaluate the predictive accuracy of the Systematic Coronary Risk Evaluation (SCORE) project high-risk function in Norway. METHODS AND RESULTS: We included 57 229 individuals screened in 1985-1992 from two population-based surveys in Norway (age groups 40-49, 50-59, and 60-69 years). The data have been linked to the Norwegian Cause of Death Registry. The SCORE high-risk algorithm for the prediction of 10-year cardiovascular disease (CVD) mortality was applied, and the risk factors entered into the model were age, sex, total cholesterol, systolic blood pressure, and smoking (yes/no). The number of expected events estimated by the SCORE model (E) was compared with the observed numbers (O). The SCORE low-risk algorithm was studied for comparison. In men, the observed number of CVD deaths was 718, compared with 1464 estimated by the SCORE high-risk function (O/E ratios 0.53, 0.53 and 0.45, for age groups 40-49, 50-59 and 60-69, respectively). In women, the observed and expected numbers were 226 and 547. The O/E ratios decreased with age (ratios 0.60, 0.45 and 0.37, respectively), i.e. the overestimation increased with age. The low-risk function predicted reasonably well for men (ratios 0.85, 0.92 and 0.79, respectively), whereas an overestimation was found for women aged 50-59 and 60-69 years (ratios 0.69 and 0.56, respectively). CONCLUSION: The SCORE high-risk model overestimated the number of CVD deaths in Norway. Before implementation in clinical practice, proper adjustments to national levels are required.  相似文献   
3.
Circulating monocytes from hypertensive patients show elevated secretion patterns of pro-inflammatory cytokines, an increased expression of adhesion molecules, and an increased adhesion to vascular endothelial cells. We tested the hypothesis that telmisartan, an angiotensin II type 1 (AT(1)) receptor antagonist, reduces the activation of circulating monocytes from hypertensive patients and diminishes the monocyte-endothelial cell adhesion. Monocytes of 20 hypertensive patients and 20 normotensive controls were isolated by density gradient centrifugation and Dynabeads, and the monocyte adhesion to human aortic endothelial cell monolayers was measured by adhesion assays. To characterize monocyte activation we assessed the expression of activity-related cell surface markers that are also involved in monocyte adhesion to endothelial cells, such as CD11a/b and CD54, as well as the chemokine receptors CCR1, CCR2 and CCR5 before and after telmisartan therapy using flow cytometry. Spontaneous adhesion of monocytes from hypertensive patients and the adhesion after stimulation with angiotensin II were significantly increased compared with those in normotensive controls (p<0.05). Treatment of hypertensive patients with the AT(1) receptor antagonist telmisartan significantly diminished the adhesion of circulating monocytes to human endothelial cells (p=0.02) despite the increase in the expressions of CD11b, CD54 and CCR5 after telmisartan therapy. Reducing monocyte adhesion may be a novel beneficial effect of the AT(1) receptor antagonist telmisartan helping to prevent vascular alterations in hypertension. The mechanism of action remains to be elucidated, since reduction in monocyte adhesion was not attributable to changes in adhesion molecule expression.  相似文献   
4.
Summary -Conotoxin GVIA (-CT) diminished the potassium-induced in vitro release of 3H--aminobutyric acid (3H-GABA) from slices of rat neostriatum in a manner which depended on the concentration of potassium. -CT (0.1 nmol/l) decreased the release of 3H-GABA induced by 25 mmol/l K+ from 11.6% to 6.1% of tissue content, ie. by 48%, while it did not affect the release of 3H-GABA caused by 20 mmol/l K+, which was 4.8% of tissue content. However, in the presence of a polyclonal antiserum or cysteamine (600 mol/l), both of which diminish the effects of endogenous somatostatin, 0.1–10 nmol/l -CT decreased the release of 3H-GABA induced by 20 mmoles/l K+ by 40%. It is concluded that -CT did not only inhibit GABA-neurones, but had an additional inhibitory effect on somatostatin neurones which are known to depress the release of 3H-GABA. It is further concluded that neuronal interactions, which are possible in brain slice preparations, may impede the interpretation of effects of drugs, especially if agents are used which affect basic mechanisms of transmitter release and thus the release of various transmitters from neurones. Send offprint requests to D. K. Meyer at the above address  相似文献   
5.
The genetic transformation of plastids of higher plants has developed into a powerful approach for both basic research and biotechnology. Due to the high copy number of the plastid genome per plastid and per cell, repeated cycles of shoot regeneration under conditions selective for the modified plastid chromosome are required to obtain transformants entirely lacking wild-type plastid genomes. The presence of promiscuous plastid DNA in nuclear and/or mitochondrial genomes that generally contaminate even gradient-purified plastid fractions reduces the applicability of the highly sensitive PCR approach to monitor the absence of residual wild-type plastid chromosomes in transformed lines. It is therefore difficult, or even impossible, to assess reliably the hetero- or homoplastomic state of plastid transformants in this manner. By analysing wild-type and transplastomic mutants of tobacco, we demonstrate that separation of plastid chromosomes isolated from gradient-purified plastid fractions by pulsed-field gel electrophoresis can overcome the problem of (co)amplification of interfering promiscuous plastid DNA. PCR analyses with primers specific for plastid, mitochondrial and nuclear genes reveal an impressive purity of such plastid DNA fractions at a detection limit of less than one wild-type plastid chromosome copy per ten transplastomic cells.  相似文献   
6.
We have disrupted expression of the mitochondrial Friedreich ataxia protein frataxin specifically in murine hepatocytes to generate mice with impaired mitochondrial function and decreased oxidative phosphorylation. These animals have a reduced life span and develop multiple hepatic tumors. Livers also show increased oxidative stress, impaired respiration and reduced ATP levels paralleled by reduced activity of iron-sulfur cluster (Fe/S) containing proteins (ISP), which all leads to increased hepatocyte turnover by promoting both apoptosis and proliferation. Accordingly, phosphorylation of the stress-inducible p38 MAP kinase was found to be specifically impaired following disruption of frataxin. Taken together, these findings indicate that frataxin may act as a mitochondrial tumor suppressor protein in mammals.  相似文献   
7.
Salmonella enterica subsp. enterica serovar Agona was not frequently encountered in Finland until an increase in rates of isolation among animal and feed was seen in 1994. A small outbreak among cattle farms in the regions of Oulu and Vaasa in northwestern Finland in 1994-1995 included eight farms. After the outbreak, an increase in the number of serovar Agona infections in humans was seen in 1999: the number of annual microbiologically confirmed cases in humans increased from about 10 from 1990 to 1998 to 84 in 1999, including an outbreak in which more than 50 people were infected. To gather epidemiological data on serovar Agona and to trace the origin of the human infections, 110 serovar Agona isolates isolated from animal, feed, and other sources as well as from humans with cases of salmonellosis of domestic and foreign origin, which were recovered from 1984 to 1999, were analyzed for their pulsed-field gel electrophoresis (PFGE), plasmid, and IS200 profiles and antibiograms. Of these typing methods, PFGE with restriction endonucleases XbaI, BlnI, NotI, and SpeI was the most useful. The PFGE profile of the strain causing an outbreak among cattle in Finland in 1994-1995 was not seen previously. The strain with this profile was later only sporadically found in human infections. The profile of the strain causing the human outbreak in 1999 was not found among isolates from cattle or any other sources. Molecular typing was valuable in showing that although the outbreaks in cattle and humans seemed to be related regionally, they were not related otherwise.  相似文献   
8.
Direct smear examination with Ziehl-Neelsen (ZN) staining for the diagnosis of tuberculosis (TB) as employed in most low-income countries is cheap and easy to use, but its low sensitivity is a major drawback. The low specificity of chest X-rays, used for the diagnosis of smear-negative TB, risks high levels of overdiagnosis. Major advances in molecular techniques, which rapidly identify mycobacterial DNA in sputa, may overcome these obstacles. In this study, the AMPLICOR PCR system was used to diagnose pulmonary TB in a developing country with high prevalences of both TB and human immunodeficiency virus (HIV). The sensitivity and specificity of this technique were compared to those of the usual diagnostic techniques. Sputum specimens were collected from 1,396 TB suspects attending the Rhodes Chest Clinic, Nairobi, Kenya. The specimens were analyzed for the presence of Mycobacterium tuberculosis by PCR; culture on Löwenstein-Jensen medium was used as the “gold standard.” All culture-positive samples were genotyped to identify the mycobacterial species. The sensitivity and specificity of PCR were 93 and 84%, respectively. HIV status did not affect the sensitivity of PCR. A total of 99.7% of the true smear-positive and 82.1% of the true smear-negative TB patients were correctly identified by PCR. PCR detected M. tuberculosis in 11.7% of the culture-negative suspects, 60% of which had one or two PCR-positive sputum specimens. Of the 490 positive cultures, 486 were identified as M. tuberculosis. The high sensitivity of Amplicor PCR merits usage in a clinical setting with high TB and HIV burdens. Thus, PCR can be considered as an alternative to ZN staining in combination with chest X-ray for diagnosis of TB; however, cost-effectiveness studies and operational studies are required to support an evidence-based decision of introducing PCR for TB control in high-burden environments.Tuberculosis (TB) is one of the most serious infectious diseases and a considerable public health problem due to its high risk of person-to-person transmission, morbidity, and mortality. Both the human immunodeficiency virus (HIV) epidemic and social deterioration have contributed to the overall increase in the Mycobacterium tuberculosis infection rate, especially in developing countries, where resources are scarce (13). In Nairobi the case detection rate increased from 78 per 100,000 in 1991 to 581 per 100,000 in 2001, with a total number of 12,963 cases.Early diagnosis followed by adequate treatment is essential to prevent both morbidity and mortality. Although the conventional technique of direct smear examination with Ziehl-Neelsen staining (ZN) is cheap and easy to perform, its low sensitivity is a major drawback. Depending on the number of specimens examined, ZN detects 30 to 60% of the culture-positive “TB suspects” (7). Furthermore, it requires sputum samples collected on consecutive days, making the procedure slow and making patient compliance with the diagnostic process difficult.New techniques are very much needed (7), and molecular amplification assays such as PCR have been shown to be promising alternatives even for developing countries (2). PCR has the potential to be a cost-effective alternative, provided the diagnosis can be determined with one sputum examination (8). If diagnosis can be established faster, and the diagnostic process becomes less cumbersome for the patient, PCR may reduce delay both in diagnosis and in the start of treatment.Depending on the “gold standard” and other methodological factors, studies show PCR sensitivities ranging from 77% to more than 95% and PCR specificities of >95% for smear-positive specimens (4, 9, 10, 12). However, sensitivities for smear-negative TB patients have been reported to be below 90% (9). Most PCR studies have been performed in industrial countries (4, 9, 10, 12) where the TB and HIV burdens are low.To investigate the performance and feasibility of PCR in an environment of TB endemicity and high prevalences of HIV and AIDS, a study was conducted in Nairobi, Kenya, comparing PCR to conventional routine diagnostic methods within a program setup. In this study, the Roche Amplicor Mycobacteria PCR test for the direct detection of M. tuberculosis was used on sputum specimens from TB suspects attending a chest clinic in Nairobi. Its performance was compared with those of the basic routine diagnostic procedures according to the national guidelines (6), including clinical findings, ZN, and chest X-rays (CXR), on smear-negative suspects. Löwenstein-Jensen (LJ) culture results were used as the gold standard.  相似文献   
9.
Emmonsia crescens, a dimorphic fungus of the order Onygenales, is primarily a pathogen of lower animals and rarely humans. Inhaled conidia of E. crescens fail to germinate in the lungs, and instead simply enlarge in lung tissue to become giant adiaspores. We present here the case of fatal Emmonsia crescens infection in a wild-caught British water vole (Arvicola terrestris). Histopathological examination of the animal, which died in captivity, revealed a multifocally extensive granulomatous reaction containing oval adiaspores scattered irregularly throughout the lungs. Mycological examination of fungus cultured from lung tissue and PCR amplification and sequencing of rDNA gene fragments of the cultured organism confirmed the diagnosis of massive infection by E. crescens.  相似文献   
10.
BACKGROUND: Spontaneous reductions are a possible cause of the increased morbidity in IVF singletons. The aim of this study was to assess incidence rates of spontaneous reductions in IVF/ICSI twin pregnancies and to compare short- and long-term morbidity in survivors of a vanishing co-twin with singletons and born twins. METHODS: We identified 642 survivors of a vanishing co-twin, 5237 singletons from single gestations and 3678 twins from twin gestations. All children originated from pregnancies detected by transvaginal sonography in gestational week 8. By cross-linkage with the national registries the main endpoints were prematurity, birth weight, neurological sequelae and mortality. RESULTS: Of all IVF singletons born, 10.4% originated from a twin gestation in early pregnancy. Multiple logistic regression analyses adjusted for maternal age, parity and ICSI treatment showed for birth weight <2500 g an odds ratio (OR) of 1.7 [95% confidence interval (CI) 1.2-2.2] and for birth weight <1500 g OR 2.1 (95% CI 1.3-3.6) in singleton survivors of a vanishing twin versus singletons from single gestations; corresponding figures were seen for preterm birth. This increased risk was almost entirely due to reductions that occurred at >8 weeks gestation. We found no excess risk of neurological sequelae in survivors of a vanishing co-twin versus the singleton cohort; however, OR of cerebral palsy was 1.9 (95% CI 0.7-5.2). Furthermore, we observed a correlation between onset of spontaneous reduction, i.e. the later in pregnancy the higher the risk of neurological sequelae (r = -0.09; P = 0.02). Adjusted OR of child death within the follow-up period was 3.6 (95% CI 1.7-7.6) in the survivor versus the singleton cohort. CONCLUSIONS: One in 10 IVF singletons originates from a twin gestation. Spontaneous reductions that occur at >8 weeks gestation are one of the causes for the higher risk of adverse obstetric outcome in IVF singletons.  相似文献   
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