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11.
T-cell based immunotherapy is an attractive approach for the treatment of multiple tumor types including cervical carcinoma. Immunostimulating DNA containing unmethylated cytosine-guanine (CpG) motifs have been successfully used as adjuvants to enhance immune responses to vaccines designed to trigger antitumor T-cell responses. Using a murine model of cervical carcinoma, we report here that repeated administration of synthetic oligodeoxynucleotides bearing CpG motifs (CpG-ODNs) without the need of vaccination into animals bearing large, established tumors resulted in significant antitumor effects. Both tumor regressions and extended survival resulting from CpG-ODN therapy required the participation of CD8+ T cells. On the other hand, CD4+ T cells were not only not required, but also appeared to inhibit the therapeutic effect of CpG-ODN. Tumor regression correlated with increased infiltration of CD8+ T cells into the tumors and with enhanced expression of MHC class I and II antigens by the tumor cells. Together, these results indicate that CpG therapy could be promising as a single agent for the treatment of some tumors such as cervical carcinoma.  相似文献   
12.
Regular follow-up is required in patients with previous intervention for coarctation of the aorta to detect recoarctation or aneurysm formation. In this study we describe the findings encountered on routine follow-up exams and we compare the use of contrast-enhanced 3D MR angiography (CE MRA) with fast spin-echo MRI (FSE) to study the thoracic aorta after previous intervention. In 51 consecutive patients previously treated for aortic coarctation, 74 MR studies of the thoracic aorta were performed during a 2-year period using CE MRA and FSE MRI. The thoracic aorta was evaluated for abnormalities of course, caliber, shape, and pathology of side branches. The CE MRA and FSE MRI studies were evaluated side by side by consensus of two reviewers evaluating which MR technique depicted the abnormalities of the thoracic aorta the best. Of 74 exams, six clinically important abnormalities were found: four aneurysms and two restenoses. Two small pseudoaneurysms were missed on the FSE studies. Contrast-enhanced MRA was judged to visualize aortic abnormalities better than FSE (47 of 74 MR studies) especially for the transverse aortic arch, coarctation site, left subclavian artery, and aortic arch configuration. For the ascending aorta and distal descending aorta, CE MRA and FSE performed equally well. Aortic diameters measured at four levels in the first 18 MRI studies showed no significant differences in diameter when measured by FSE or CE MRA (p = not significant). Clinically important abnormalities, such as aneurysm formation and restenosis, can be present years after treatment for aortic coarctation. In the regular follow-up of these patients, CE MRA may provide additional diagnostic information compared with FSE and should be included as part of the routine exam. Received: 3 April 2000; Revised: 5 July 2000; Accepted: 7 July 2000  相似文献   
13.
BACKGROUND: To assess the impact of immediate versus delayed antihypertensive treatment on the outcome of older patients with isolated systolic hypertension, we extended the double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial by an open-label follow-up study lasting 4 years. METHODS: The Syst-Eur trial included 4695 randomized patients with minimum age of 60 years and an untreated blood pressure of 160-219 mmHg systolic and below 95 mmHg diastolic. The double-blind trial ended after a median follow-up of 2.0 years (range 1-97 months). Of 4409 patients still alive, 3517 received open-label treatment consisting of nitrendipine (10-40 mg daily) with the possible addition of enalapril (5-20 mg daily), hydrochlorothiazide (12.5-25 mg daily), or both add-on drugs. Non-participants (n = 892) were also followed up. RESULTS: Median follow-up increased to 6.1 years. Systolic pressure decreased to below 150 mmHg (target level) in 2628 participants (75.0%). During the 4-year open-label follow-up, stroke and cardiovascular complications occurred at similar frequencies in patients formerly randomized to placebo and those continuing active treatment. These rates were similar to those previously observed in the active-treatment group during the double-blind trial. Considering the total follow-up of 4695 randomized patients, immediate compared with delayed antihypertensive treatment reduced the occurrence of stroke and cardiovascular complications by 28% (P = 0.01) and 15% (P = 0.03), respectively, with a similar tendency for total mortality (13%, P = 0.09). In 492 diabetic patients, the corresponding estimates of long-term benefit (P < 0.02) were 60, 51 and 38%, respectively. CONCLUSIONS: Antihypertensive treatment can achieve blood pressure control in most older patients with isolated systolic hypertension. Immediate compared with delayed treatment prevented 17 strokes or 25 major cardiovascular events per 1000 patients followed up for 6 years. These findings underscore the necessity of early treatment of isolated systolic hypertension.  相似文献   
14.
The Systolic Hypertension in Europe (Syst-Eur) trial proved that blood pressure (BP) lowering therapy starting with nitrendipine reduces the risk of cardiovascular complications in older (> or = 60 years) patients with isolated systolic hypertension (systolic BP > or = 160 mm Hg and diastolic BP < 95 mm Hg). After the completion of the Syst-Eur trial on 14 February 1997, 3506 consenting patients (93.0% of those eligible) were enrolled in phase 2 of the Syst-Eur trial. This open follow-up study aims to confirm the safety of long-term antihypertensive therapy based on a dihydropyridine. To lower the sitting systolic BP below 150 mm Hg (target BP), the first-line agent nitrendipine (10-40 mg/day) may be associated with enalapril (5-20 mg/day), hydrochlorothiazide (12.5-25 mg/day), both add-on study drugs, or if required any other antihypertensive agent. On 1 November 1998, 3248 patients were still being followed, 86 patients had proceeded to non-supervised follow-up, and 43 had died. The median follow-up in Syst-Eur 2 was 14.3 months. At the last available visit, systolic/diastolic BP in the patients formerly randomised to placebo (n = 1682) or active treatment (n = 1824), had decreased by 13.2/5.2 mm Hg and by 4.6/1.6 mm Hg, respectively, so that the between-group BP difference was 1.7 mm Hg systolic (95% Ci: 0.8 to 2.6 mm Hg; P < 0.001) and 0.9 mm Hg diastolic (95% Cl: 0.4 to 1.5 mm mm Hg; P < 0.001). At the beginning of Syst-Eur 2, the goal BP was reached by 25.4% and 50.6% of the former placebo and active-treatment groups; at the last visit these proportions were 55.9% and 63.1%, respectively. At that moment, 45.9% of the patients were on monotherapy with nitrendipine, 29.3% took nitrendipine in combination with other study drugs. Until the end of 2001, BP control of the Syst-Eur 2 patients will be further improved. Cardiovascular complications and adverse events, such as cancer or gastro-intestinal bleeding, will be monitored and validated by blinded experts.  相似文献   
15.
Introduction: The risk of mortality from cardiovascular disease (CVD) is higher in wintertime throughout the world, but it is not known if this reflects annual changes in diet or lifestyle, or an endogenous photoperiodic mechanism that is sensitive to changes in day length.

Methods: Phenotypic data on cardiometabolic and lifestyle factors were collected throughout a 4 year time period from 502,642 middle-aged participants in UK Biobank. To assess the impact of seasonal environmental changes on cardiovascular risk factors, we linked these data to the outdoor temperature and day length at the time of assessment. Self-reported information on physical activity, diet and disease status were used to adjust for confounding factors related to health and lifestyle.

Results: Mortality related to CVD was higher in winter, as were risk factors for this condition including blood pressure, markers of inflammation and body mass index (BMI). These seasonal rhythms were significantly related to day length after adjustment for other factors that might affect seasonality including physical activity, diet and outdoor temperature.

Conclusions: The risk of CVD may be modulated by day length at temperate latitudes, and the implications of seasonality should be considered in all studies of human cardiometabolic health.

  • Key messages
  • In this cross-sectional study in UK Biobank, we report annual variations in cardiovascular risk factors and mortality that were associated with day length independent of environmental and lifestyle factors.

  • These seasonal changes in day length might contribute to annual patterns in cardiovascular disease and mortality.

  相似文献   
16.
Clinical Rheumatology - To compare long-term clinical, immunological, and radiographic outcomes between five sets of remission criteria (four clinical and one ultrasound (US)-based) in a cohort of...  相似文献   
17.
The Drosophila Notch gene product is a transmembrane protein that functions as a receptor of intercellular signals in several Drosophila developmental processes. Two other transmembrane proteins, encoded by the genes Delta and Serrate, genetically and molecularly behave as Notch ligands. All these proteins share the presence of epidermal growth factor (EGF)-like repeats in their extracellular domain. The Notch protein has 36 EGF-like repeats, 2 of which, numbers 11 and 12, are required for the interaction with the Delta and Serrate ligands. We have isolated and molecularly characterized a Notch mutation in its Delta- and Serrate-binding domain that behaves genetically as both a Notch antimorphic and a loss-of-function mutation. This mutation, NM1, carries a Glu-->Val substitution in the Notch EGF repeat 12. The NM1 allele interacts with other Notch alleles such as Abruptex and split and with mutations in the Notch-ligand genes Delta and Serrate. The basis for the genetic antimorphism of NM1 seems to reside in the titration of Notch wild-type products into NM1/N+ nonfunctional dimers and/or the titration of Delta products into nonfunctional ligand-receptor complexes.  相似文献   
18.
In hypophysectomized rats on day 1 of dioestrus, as well as on day 4 of pseudopregnancy, alpha-MSH (continuous infusion of 1 microgram/h) failed to maintain serum concentrations of progesterone. On the other hand, alpha-MSH did not modify the increase induced by ACTH (1 microgram/microliter as an infusion plus two additional daily injections of 30 micrograms/microliter), prolactin (200 micrograms/0.2 ml at 12-h intervals) or GH (300 micrograms/0.2 ml twice daily) on serum concentrations of progesterone in such rats. However, in intact rats alpha-MSH caused a significant rise in serum concentrations of GH on day 1 and day 2 of dioestrus. Continuous infusion of alpha-MSH produced an increase in serum concentrations of GH at 12.00 and 14.00 h on day 1 of dioestrus and at 07.00 h on day 2. It is therefore suggested that alpha-MSH may exert its effect by facilitating the secretion of GH, which in turn may induce the release of progesterone.  相似文献   
19.
TNF-α induced, in a time and dose-dependent fashion, cell-cell dissociation (dyscohesion) of endometrial epithelial cells. Within the time frame that dyscohesion was induced, TNF-α, in a dose-dependent fashion, reduced filamentous (F) actin and resulted in the loss of F-actin from the intercellular boundaries. Loss of F-actin mediated by TNF-α was not due to a reduction in the overall amount of actin or its β-isoform. Two proteins, Rho and Rho guanine nucleotide dissociation inhibitor (Rho-GDI), have been implicated in the regulation of organization of actin cytoskeleton. The reduced level of F-actin was not associated with altered expression of Rho protein, however, it was associated with an increase in the amount of Rho available for ribosylationin vitro by the C3 exoenzyme of Clostridium botulinum. The amount of Rho-GDI protein did not change after treatment with TNF-α suggesting that elevated expression of this protein is not responsible for the disassembly of actin filaments. These findings show that TNF-α induces dyscohesion. Dyscohesion induced by this cytokine is associated with perturbation of the actin cytoskeleton which may be due to the regulatory role of TNF-α on Rho.  相似文献   
20.
Microsomal preparations from the stalk median eminence of female rats are shown to contain an enzymic activity that is responsible for the formation of MSH-release-inhibiting factor (MSH-R-IF). The amount of this activity remains constant throughout the estrous cycle. The corresponding mitochondrial preparations from the stalk median eminence contain another enzymic principle, estrous cycle-dependent, which competes with the enzyme present in the microsomal preparation for the same "substrate", and can thereby prevent the formation of MSH-R-IF.Several neurohypophyseal hormones, analogs, and peptide intermediates have been tested for their intrinsic MSH-R-IF activity and for their ability to be transformed into MSH-R-IF by incubation with microsomal preparations of stalk median eminence from male rats; it is concluded that the enzyme responsible for the formation of MSH-R-IF is an exopeptidase and that the release-inhibiting factor itself is a tripeptide. Oxytocin is converted by the incubation to (L)-prolyl-(L)-leucylglycinamide; nanogram amounts of this tripeptide inhibit the release of MSH from the pituitary both in vivo and in vitro.  相似文献   
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