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991.
Hepatocyte activator inhibitor-1 (HAI-1) is a transmembrane serine protease inhibitor that regulates the conversion of latent to active hepatocyte growth factor (HGF). Studies supporting a role for the HGF pathway in prostate carcinogenesis prompted an analysis of HAI-1 expression in the prostate. Here we analyze the regulation of HAI-1 expression by androgen, oncogenic transformation, and cancer progression. Immunohistochemical analysis revealed that HAI-1 expression was restricted to prostate epithelium, where staining occurred primarily in basal and atrophic luminal epithelial cells. Compared to normal glands, HAI-1 expression was significantly increased in localized prostate cancer and was present in most prostate cancer metastases. HAI-1 protein expression levels were sensitive to androgen in normal epithelium but not in cancer. Although androgen did not increase HAI-1 protein expression levels in LNCaP cells, it decreased HAI-1 surface expression, consistent with previous data from our group (Martin DB, Gifford DR, Wright ME, Keller A, Yi E, Goodlett DR, Aebersold R, Nelson PS: Quantitative proteomic analysis of proteins released by neoplastic prostate epithelium. Cancer Res 2004, 64:347-355). HAI-1 overexpression in cancer was predictive of prostate-specific antigen recurrence (relative risk, 1.24). These results suggest that HAI-1 regulates the HGF Met axis on prostate epithelial cells and influences HGF mediated tumor invasion and metastasis.  相似文献   
992.
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994.
Objective: Previous work has shown that manic-depressive illness and alcohol abuse are linked. This study further explores the relationship of alcohol and drug abuse in bipolar I patients and unipolar depressives and a comparison group obtained through the acquaintance method. Method: Diagnosis was accomplished according to Research Diagnostic Criteria (RDC): controls=469; bipolars=277; unipolar depressives=678. Systematic data were gathered using the SADS on lifetime and current drug abuse and alcoholism. Both patients and comparison subjects were then followed prospectively for 10 years. First degree family members were interviewed using the RDC family history method. Results: The group of bipolar patients and the group of unipolar patients had higher rates of drug and alcohol abuse than the comparison group when primary and secondary affective disorder patients were combined. However, primary unipolar patients did not have higher rates of alcohol or drug abuse than the comparison group. In contrast, primary bipolar patients had higher rates of alcoholism, stimulant abuse, and ever having abused a drug than the primary unipolar group and the control group. In an evaluation of the bipolar patients, drug abusers were significantly younger at intake and had a significantly younger age of onset of bipolar disorder. There was a significant increase in family history of mania or schizoaffective mania in the drug-abusing bipolar patients as compared to the non-abusing bipolar patients. Limitation: As in all adult samples of patients with affective illness, the chronology of alcohol and substance problems vis-à-vis the onset of illness was determined retrospectively. Conclusions: (1) Alcoholism and drug abuse are more frequent in bipolar than unipolar patients. (2) The drug abuse of bipolar patients tends toward the abuse of stimulant drugs. (3) In a bipolar patient, familial diathesis for mania is significantly associated with the abuse of alcohol and drugs. (4) More provocatively, these findings suggest the hypothesis of a common familial-genetic diathesis for a subtype of bipolar I, alcohol and stimulant abuse. Clinical implications: The present analyses, coupled with two previous ones from the CDS, suggest that drug abuse may precipitate an earlier onset of bipolar I disorder in those who already have a familial predisposition for mania. Furthermore, in dually diagnosed patients with manic-depressive and alcohol/stimulant abuse history, mood stabilization of the bipolar disorder represents a rational approach to control concurrent alcohol and drug problems, and should be studied in systematic controlled trials.  相似文献   
995.
Our objective was to correlate p16, p21cip1, p27kip1, and cyclin E protein expression with the degree of dysplasia on ThinPrep Papanicolaou (Pap) smears using a modified immunoperoxidase staining. Smears read as normal, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), or high-grade SIL (HSIL) were identified and tested for high-risk human papillomavirus (HR-HPV). Additional smears were processed for immunoperoxidase for p16, p21cip1, p27kip1, and cyclin E. Thirty-four smears were satisfactory for study. The p16 was positive in all nine HSIL, in four of nine LSIL, and in one of seven ASC-US. The p27kip1 was positive in all nine HSIL, in eight of nine LSIL, and in one of seven ASC-US. The p21cip1 was positive in all nine HSIL, in one of nine LSIL, and in one of seven ASC-US. Cyclin E was positive in seven of nine HSIL and in one of nine LSIL and in none of the ASC-US smears. Normal smears were negative for all the antigens. There was poor correlation of protein expression and HR-HPV infection. We concluded that p16, p21cip1, p27kip1, and cyclin E can be demonstrated on Pap smears and they are expressed differentially in dysplastic cells, with highest expression in HSIL. The p21cip1 and cyclin E showed the greatest correlation with HSIL.  相似文献   
996.
997.
Comprehensive genome scans involving many thousands of SNP assays will require significant amounts of genomic DNA from each sample. We report two successful methods for amplifying whole-genomic DNA prior to SNP analysis, multiple displacement amplification, and OmniPlex technology. We determined the coverage of amplification by analyzing a SNP linkage marker set that contained 2320 SNP markers spread across the genome at an average distance of 2.5 cM. We observed a concordance of >99.8% in genotyping results from genomic DNA and amplified DNA, strongly indicating the ability of both methods used to amplify genomic DNA in a highly representative manner. Furthermore, we were able to achieve a SNP call rate of >98% in both genomic and amplified DNA. The combination of whole-genome amplification and comprehensive SNP linkage analysis offers new opportunities for genetic analysis in clinical trials, disease association studies, and archiving of DNA samples.  相似文献   
998.
We investigated the physiological responses in older men to continuous (CEx) and intermittent (IEx) exercise. Nine men [70.4 (1.2) years, O2peak: 2.21 (0.20) l min–1; mean (SE)] completed eight exercise tests (two CEx and six IEx) on an electronically braked cycle ergometer in random order. CEx and IEx were performed at 50% and 70% O2peak. IEx was performed using 60sE:60sR, 30sE:30sR and 15sE:15sR exercise to rest ratios. The duration of exercise was adjusted so that the total amount of work completed was the same for each exercise test. Oxygen uptake (O2), minute ventilation (E) and heart rate (HR) were measured at the mid-point of each exercise test. Arterialised blood samples were obtained at rest and during exercise and analysed for pH and PCO2. At the same relative intensity (50% or 70% O2peak), IEx resulted in a significantly lower (P<0.01) O2, E and HR than CEx. There were no significant differences (P>0.05) in O2, E and HR measured at the mid point of the three exercise to rest ratios at 50% and 70% O2peak. pH and PCO2 during CEx and IEx at 50% O2peak were not significantly different from rest. CEx performed at 70% O2peak resulted in significant decreases (P<0.05) in pH and PCO2. There was a significant decrease (P<0.05) in pH only during the 60sE:60sR IEx at 70% O2peak. Changes in arterialised PCO2 during the 60sE:60sR, 30sE:30sR and 15sE:15sR at both 50% and 70% O2peak exercise tests were not significant. When exercising at the same percentage of O2peak and with the total amount of work fixed, IEx results in significantly lower physiological responses than CEx in older men. All results are given as mean (SE).  相似文献   
999.
BACKGROUND: Antenatal sickle cell and thalassaemia screening sometimes occurs too late to allow couples a choice regarding termination of affected fetuses. The target gestational age for offering the test in the UK is 10 weeks. AIM: To describe the proportion of women screened before 70 days' (10 weeks') gestation and the delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening. DESIGN OF STUDY: Cohort study of reported pregnancies. SETTING: Twenty-five general practices in two UK inner-city primary care trusts offering universal screening. METHOD: Anonymised data on all pregnancies reported to participating general practices was collected for a minimum of 6 months. RESULTS: There were 1441 eligible women intending to proceed with their pregnancies, whose carrier status was not known. The median (interquartile range [IQR]) gestational age at pregnancy confirmation was 7.6 weeks (6.0-10.7 weeks) and 74% presented before 10 weeks. The median gestational age at screening was 15.3 weeks (IQR = 12.6-18.0 weeks), with only 4.4% being screened before 10 weeks. The median delay between pregnancy confirmation and screening was 6.9 weeks (4.7-9.3 weeks) After allowing for practice level variation, there was no association between delay times and maternal age, parity, and ethnic group. CONCLUSION: About 74% of women consulted for pregnancy before 10 weeks' gestation but fewer than 5% of women were screened before the target time of 10 weeks. Reducing the considerable delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening requires methods of organising and delivering antenatal care that facilitate earlier screening to be developed and evaluated.  相似文献   
1000.
Ruminants are regarded as a primary reservoir for Escherichia coli O157:H7, an important human pathogen. Intimin, encoded by the Locus of Enterocyte Effacement by E. coli O157:H7 organisms, has been cited as one bacterial mechanism of colonisation of the gastrointestinal tract. To confirm this and to test whether a non-toxigenic E. coli O157:H7 strain would colonise and persist in a sheep model, E. coli O157:H7 strain NCTC12900, that lacks Shiga toxin (stx) genes, was evaluated for use in a sheep model of persistence. Following oral inoculation of six-week-old sheep, persistent excretion of NCTC12900 was observed for up to 48 days. E. coli O157-associated attaching-effacing (AE) lesions were detected in the caecum and rectum of one six-week-old lamb, one day after inoculation. This is the first recorded observation of AE lesions in orally inoculated weaned sheep. Also, mean faecal excretion scores of NCTC12900 and an isogenic intimin (eae)-deficient mutant were determined from twenty-four six-week-old orally inoculated sheep. The eae mutant was cleared within 20 days and had lower mean excretion scores at all time points after day one post inoculation compared with the parental strain that was still being excreted at 48 days. Tissues were collected post mortem from animals selected at random from the study groups over the time course of the experiment. The eae mutant was detected in only 1/43 samples but the parental strain was recovered from 64/140 samples primarily from the large bowel although rumen, duodenum, jejunum, and ileum were culture positive especially from animals that were still excreting at and beyond 27 days after inoculation.  相似文献   
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