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981.
Chromosomal rearrangements that result in high expression levels of the ETS-related gene (ERG) present in approximately 50% of prostate cancer (PCa) patients, making this one of the most common oncogenic alterations in PCa. However, ERG overexpression at the protein level has not been rigorously evaluated in Japanese PCa patients. In this study, we evaluated ERG expression using antibody-based detection in 230 prostate specimens in a Japanese PCa cohort. Overall, we identified 20.1% ERG-positive PCa cases. ERG was not detected in benign glands. The specificity of ERG staining for detecting PCa was almost 100%; all of the ERG-positive samples were also diagnosed as PCa. The expression level of the ERG protein correlated with clinicopathological variables, including grade (P= 0.038), stage (P= 0.005), and metastatic status (P= 0.014). No correlation was observed with age (P= 0.196) or with preoperative prostate-specific antigen level (P= 0.322). Although the frequency of ERG-positive cases in Japanese PCa patients (20.1%) was lower than that reported in a PCa cohort in Western countries (approximately 50%), our study demonstrates that the clinical utility of ERG detection at the protein level can serve as an ancillary tool for diagnosing PCa in the Japanese population.  相似文献   
982.
AIMS: Potassium sensitivity test (PST) has been used as an optional tool in diagnosing painful bladder syndrome/interstitial cystitis (PBS/IC). The role of PST in the follow-up of patients with PBS/IC is elusive. We performed PST before and after treatment of PBS/IC with cyclosporine A (CyA) or pentosan polysulfate sodium (PPS), to test whether the result of repeated PST correlates with alleviation of PBS/IC-related symptoms. MATERIALS AND METHODS: Sixty-four patients who participated in a randomized clinical study comparing CyA and PPS in the treatment of PBS/IC were recruited to the present study. Patients underwent 0.4 M PST before and after 6 months of treatment. The primary end point was a change from positive PST to negative among patients who responded to both treatments determined by global response assessment (GRA). RESULTS: Potassium sensitivity test (PST) was more likely to change from positive to negative among patients who responded to their treatment according to GRA (P < 0.001). The PST change follows the clinical course (ICSI score, voiding frequency, VAS score), which was more beneficial in the CyA-treated patients. CONCLUSIONS: Potassium sensitivity test (PST) reflects symptom severity of PBS/IC patients. Change of pre-treatment positive PST to negative correlates well with clinical alleviation of PBS/IC-related symptoms. In patients with persistent symptoms it may be painful and does not offer additional information. Thus, we do not recommend PST to be used as a routine clinical test in monitoring of PBS/IC treatment efficacy.  相似文献   
983.
The Nordic countries have a long tradition of large-scale biobanking and comprehensive, population-based health data registries linkable on unique personal identifiers, enabling follow-up studies spanning many decades. Joint Nordic biobank-based studies provide unique opportunities for longitudinal molecular epidemiological research. The purpose of the present paper is to describe the possibilities for such joint studies, by describing some of the major Nordic biobank cohorts with a standardised calculation of the cancer incidence in these cohorts. Altogether two million donors have since 1966 donated more than four million biological samples, stored at -20 degrees C to -135 degrees C, to 17 biobank cohorts in Finland, Iceland, Norway and Sweden. As a result of joint database handling principles, the accuracy of personal identifiers and completeness of follow-up for vital status in all participating biobanks was improved. Thereafter, the cancer incidence was determined using follow-up through the national cancer registries. Biobanks based on random samples of population typically showed slightly lower cancer incidence rates than the general population, presumably due to better participation rates among health-conscious subjects. On the other hand, biobanks including samples for viral screening or clinical testing showed 1.5 to 2.1 fold increased incidence of cancer. This excess was very high immediately after sampling, but for some cancer sites remained elevated for years after clinical sampling. So far, more than 100 000 malignant neoplasms have occurred after sample donation, and the annual increase of the cancer cases in these cohorts is about 10 000. The estimates on the population-representativity of the biobanks will assist in interpretation of generalizability of results of future studies based on these samples, and the systematic tabulations of numbers of cancer cases will serve in study power estimations. The present paper summarizes optimal study designs of biobank-based studies of cancer.  相似文献   
984.
Positron emission tomography (PET) with 2-deoxy-2[(18)F]-fluoro-D-glucose (FDG) can be used to estimate regional cerebral glucose metabolism (rCMRgluc). FDG-PET studies have shown rCMRgluc to be reduced especially in temporal and parietal cortices in Alzheimer's disease (AD). A previous study on monozygotic twins discordant for AD showed that the rCMRgluc of the non-demented twins is reduced significantly in the lateral temporal and parietal cortices compared to unrelated controls. In this study we examined 9 pairs of dizygotic twins discordant for AD with FDG-PET. The rCMRgluc of the demented twins was 16% lower in the prefrontal cortex (p = 0.04), 20% lower in the hippocampus (p = 0.002) and 15% lower in the lateral temporal cortex (p = 0.003) compared to controls. The non-demented twins showed no such reductions on any cortical region compared to unrelated control subjects. This implies that both genes and environment, and not genes alone, are causative in the pathogenesis of AD.  相似文献   
985.
Little is known about the effect of mechanical treatment on the intervertebral disc in the management of low back pain, even though good clinical results are often claimed for this treatment. In order to understand the possible effects of this treatment, cadaveric lumbar motion segments were studied with discography at 103 levels in 19 lumbar spine specimens. Fifty-four motion segments were tested with repeated extension/compression moments and evaluation of the changes in discogram dye pattern was made. In 43% increased dye leakage was observed, while 31% of those studied showed some degree of increased bulging, and in 2% there was evidence of decreased bulging. The major effect of repeated extensions moments on the cadaveric lumbar motion segment appears to lie in forcing dye from the nucleus pulposus into the spinal epidural space, or some peridiscal space in many abnormal discs.  相似文献   
986.
Cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase-2 (NOS-2) each have an important role in angiogenesis. The expression of these genes was investigated in human prostate cancer by immunohistochemistry, the expression of COX-1 and COX-2 being confirmed by mRNA analysis. Prostate cancer specimens from 12 patients were compared to control prostates from 13 patients operated on for bladder carcinoma. The intensity of COX-2 and NOS-2 immunostaining was significantly stronger in prostate cancer cells than in the non-malignant glandular epithelium of the control prostates. COX-2 and NOS-2 were clearly also expressed in the lesions of prostatic intraepithelial neoplasia (PIN) in control prostates. COX-2 was detected in the muscle fibres of the hyperplastic stroma of some control prostates. No significant difference was detected in COX-1 expression between control and cancer prostates. These results indicate that the expression of COX-2 and NOS-2 is elevated in prostatic adenocarcinoma and in PIN. Received: 18 April 2000 / Accepted: 11 September 2000  相似文献   
987.
Atrial fibrillation (AF) is the most common arrhythmia, with an incidence of 17-33%, after coronary artery bypass grafting (CABG) and it increases the cost of operative treatment. beta-Blocker therapy reduces markedly the incidence of postoperative AF. The more effective preventive methods, e.g. amiodarone therapy or atrial pacing, are not cost-effective for all the patients. Thus, identification of patients at high risk of AF after CABG would be helpful. This review summarizes the predictors of postoperative AF and the current methods for risk stratification. In summary, identification of the patients at high risk of postoperative AF remains a challenge. The clinical usefulness of most of the conventional factors, e.g. age or history of AF, is low. Even attempts to build logistic regression models based on the pre- and intraoperative variables have failed to provide powerful predictors for postoperative AF after CABG. From the new predictors, the P-wave duration in signal-averaged ECG looks promising. Sensitivity and negative predictive value are high, positive predictive value remains low, which limits its usefulness. Contrary, even detailed analysis of standard 12-lead ECG or measure of heart rate variability has failed to provide useful information for risk stratification. A new method for risk stratification has been developed in our centre. The diagnostic accuracy of high-rate atrial pacing seems to be sufficient to identify a group of patients to whom prophylactic treatment could be proactively targeted. Further experience is, however, warranted to verify significance of this method in everyday clinical practice.  相似文献   
988.
Various novel morpholinyl- (3a,b) and methylpiperazinylacyloxyalkyl (3c-f) esters of 2-(6-methoxy-2-naphthyl)propionic acid were synthesized and evaluated in vitro for topical drug delivery as potential prodrugs of naproxen (1). Compounds 3a-f were prepared by coupling the corresponding naproxen hydroxyalkyl ester with the morpholinyl- or (4-methyl-1-piperazinyl)acyl acid in the presence of dicyclohexylcarbodiimide (DCC) and 4-(dimethylamino)pyridine (DMAP) and quantitatively hydrolyzed (t(1/2) = 1-26 min) to naproxen in human serum. Compounds 3c-f showed higher aqueous solubility and similar lipophilicity, determined by their octanol-buffer partition coefficients (log P(app)), at pH 5.0 when compared to naproxen. At pH 7.4 they were significantly more lipophilic than naproxen. The best prodrug 3c led to a 4- and 1.5-fold enhancement of skin permeation when compared to naproxen at pH 7.4 and 5.0, respectively. The present study indicates using a methylpiperazinyl group yields prodrugs that are partially un-ionized under neutral and slightly acidic conditions, and thus, a desirable combination is achieved in terms of aqueous solubility and lipophilicity. Moreover, the resulting combination of biphasic solubility and fast enzymatic hydrolysis of the methylpiperazinylacyloxyalkyl derivatives gave improved topical delivery of naproxen.  相似文献   
989.
990.

Objective

To examine the allelic diversity of structural, inflammatory, and matrix‐modifying gene candidates and their association with disc degeneration.

Methods

Subjects were 588 men ages 35–70 years. We investigated associations of single‐nucleotide polymorphisms in AGC1 and in 12 collagen, 8 interleukin, and 4 matrix metalloproteinase genes with quantitative magnetic resonance imaging measurements of disc desiccation and disc bulging and height narrowing scores, after controlling for age and suspected risk factors. Analyses were performed using QTDT software. P values were derived from 1,000 permutations, and empirical P values for global significance also were applied.

Results

Twelve of the 99 variants in 25 selected candidate genes provided evidence of association (P < 0.05) with disc signal intensity in the upper and/or lower lumbar regions. Allelic variants of AGC1 (rs1042631; P = 0.001), COL1A1 (rs2075555; P = 0.005), COL9A1 (rs696990; P = 0.00008), and COL11A2 (rs2076311; P = 0.018) genes provided the most significant evidence of association with disc signal intensity. The same variants of AGC1 (P = 0.010) and COL9A1 (P = 0.014), as well as variants in the COL11A1 gene (rs1463035 [P = 0.004]; rs1337185 [P = 0.015]) were also associated with disc bulging, as was AGC1 with disc height narrowing (rs1516797; P = 0.005). In addition, 4 allelic variants in the immunologic candidate genes (rs2071375 in IL1A [P = 0.027]; rs1420100 in IL18RAP [P = 0.005]) were associated with disc signal intensity.

Conclusion

Genetic variants account for interindividual differences in disc matrix synthesis and degradation. The accuracy of the quantitative disc signal intensity measurements we used likely enhanced our ability to observe these associations. Our findings shed light on possible mechanisms of degeneration and support the view that disc degeneration is a polygenetic condition.
  相似文献   
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