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81.
INTRODUCTION AND OBJECTIVES: The linked p16(INK4)/MTS1 and p15(INK4B)/MTS2 genes on chromosome 9p21 encode proteins that inhibit the cyclinD dependent kinases CDK4/6. Biallelic homozygous deletions involving this locus have been identified in a wide range of tumor cell lines, but in a lower frequency of primary tumors. As PCR based approaches analyzing for homozygous deletions could be confounded by unavoidable contributions of normal cells in microdissected tissue, we performed in situ hybridization (ISH) on primary prostate carcinomas to accurately evaluate p16 and p15 copy numbers on a cell-by-cell basis. MATERIAL AND METHODS: p16 and p15 loci were evaluated in 28 pT3N0M0 prostate cancer specimens. Of 28 patients, 15 (53%) were ascertained showing no recurrence (mean follow-up 61+/-17 months), 13 (47%) developed recurrences within 27+/-19 months. Tissues were provided for ISH analysis in a blinded fashion. Isolated DNA derived from P1 clone 1063 compromising p16 and p15 as well as a centromeric probe for chromosome 9 were used for hybridization. Signals were enumerated within 300 interphase nuclei per tumor specimen, and in 100 nuclei derived from 18 benign prostate tissues and 7 adjacent PIN regions. RESULTS: ISH detected aneuploid tumors in 12/13 (92%) patients with recurrence and in 5/15 (33%) without recurrence (p<0.0014). Whereas 3/7 PIN specimens associated with nonrecurrent PCA demonstrated euploidy, all 4/7 PIN associated with recurrent disease demonstrated the same aneuploidy for chr9 as the primary tumor. All benign tissues evaluated exhibited euploidy for chr9, p16 and p15. None of the PCA and PIN samples revealed homozygous deletions for p16(INK4)/MTS1/p15(INK4B)/MTS2; 2/28 (7.1%) PCA exhibited partial deletion for p16(INK4)/MTS1/p15(INK4B)/MTS2 and aneuploidy for chr9; both PCA derived from the recurrent group. CONCLUSIONS: Deletion of 9p21 was rare and therefore such genetic alterations may not play an important role in the pathogenesis of PCA. Analysis of the limited number of PCA examined suggest a strong association between chr9 aneuploidy and recurrenct disease. Aneuploidy in both PIN and PCA suggests that the clinical outcome of PCA might already be determined in the preinvasive PIN.  相似文献   
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Tephrosia purpurea (family: Fabaceae), which is used in traditional remedies for the treatment of febrile attacks, enlargement and obstruction of liver, spleen, and kidney, was found to have significant antileishmanial activity, and has been extensively fractionated to locate the abode of activity. A fraction (F062) obtained from N‐butanol extract of T. purpurea showed consistent antileishmanial activity at 50 mg/ kg × 5 days by oral route against Leishmania donovani infection in hamsters. Activity was further confirmed in a secondary model, i.e., Indian langur monkeys (Presbytis entellus). Thus, the fraction F062 from this plant possesses potential to produce significant antileishmanial activity by oral route without producing any toxic side effects. Drug. Dev. Res. 60:285–293, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
83.
Biochemical markers applicable to the ovariectomized rat model can provide important tools for studying the bone remodeling process in this animal model of postmenopausal osteoporosis. We describe the development and application of two biochemical markers, a C-telopeptide (of type-I collagen) enzyme-linked immunosorbent assay (ELISA) for measuring bone resorption and an osteocalcin radioimmunoassay (RIA) for measuring bone formation in rat serum. The C-telopeptide ELISA is based on an affinity purified polyclonal antibody generated against human sequence DFSFLPQPPQEKAHDGGR. The antibody epitope involves amino acid sequence, which is similar in rat and human carboxyl terminal peptide of type-I (alpha 1) collagen. Sensitivity of the ELISA was 0.3 ng/ml. The averaged intra- and interassay variation was CV <7%. Averaged dilution and spiked recoveries were 91% and 105%, respectively. The second marker developed is a synthetic peptide-based osteocalcin RIA, which does not require isolation and purification of intact osteocalcin from rat bone. Osteocalcin antiserum used in the RIA was generated in rabbits against a synthetic peptide comprising amino acids 33–49 of the rat osteocalcin sequence. The sensitivity of the RIA was 0.15 ng/ml of peptide. The averaged intra (n = 10) and interassay variations for two controls were CV <9% and 12%, respectively. The averaged dilution and spiked recoveries were 99.6%. In vivo validation of the C-telopeptide ELISA and osteocalcin RIA was performed in an ovariectomized (OVX) rat model. In 12-week-old OVX Sprague Dawley rats, the C-telopeptide and osteocalcin concentrations were approximately 65% and 40%, respectively, higher than the sham group. Estradiol repletion significantly lowered the C-telopeptide and osteocalcin concentration to the levels of the sham group. In addition, changes in serum C-telopeptide concentration correlated negatively with trabecular BMD measured by pQCT (r =−0.51, P < 0.001). In conclusion, the C-telopeptide ELISA and osteocalcin RIA exhibited required sensitivity, accuracy, and adequate discriminatory power to be used for measuring bone resorption and bone formation in the ovariectomized rat model. Received: 20 August 1999 / Accepted: 5 January 2000  相似文献   
84.
PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients.  相似文献   
85.
The concentration of chlorinated pesticides and heavy metals (lead and cadmium) was measured using gas liquid chromatography and the graphite tube atomizer of atomic absorption spectrophotometer, respectively, in semen samples collected from men in the normal human population. Significant concentrations of lead and cadmium were detected. Significant amounts of hexachlorocyclohexane (HCH) and its isomers alpha, beta, gamma and delta, the dichlorodiphenyl trichloroethane (DDT) metabolite 1,1,1-trichloro-2,2-bis (p chlorophenyl ethane) (pp'-DDE) and low values of 1,1,2-dichloro-2, 2-bis(p chlorophenyl ethane) (pp'-DDD) aldrin or endosulfan were detected. The presence of these xenobiotics in human semen might be related to the extensive use of pesticides, emission of exhaust from motor vehicles, consumption of tobacco and industrial operations.  相似文献   
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OBJECTIVES: The role of EEG and evoked potentials has not been evaluated in predicting the prognosis of tuberculous (TB) meningitis. The present study was aimed at evaluating the prognostic significance of clinical, radiological, and neurophysiological variables using multi-variable analysis. METHODS: Patients with TB meningitis diagnosed on the basis of clinical, radiological, and CSF criteria have been prospectively evaluated. All the patients were subjected to a detailed neurological evaluation. The outcome was defined 6 months after starting treatment on the basis of the Barthel index (BI) score into poor (BI <12) and good recovery (BI> or =12). Death was included in the poor recovery group for statistical analysis. Thirteen clinical (age, sex, seizure, focal weakness, stage of meningitis, Glasgow coma scale score, methyl prednisolone therapy), CT (infarction, hydrocephalus, tuberculoma) and neurophysiological (EEG, motor and somatosensory evoked potentials) variables were evaluated employing single variable logistic regression followed by multivariable logistic regression analysis. The best set of predictors were obtained by stepdown logistic regression analysis. RESULTS: Fifty four patients were included in the present study. Their age ranged between 5 and 62 years, 11 were children younger than 12 years and 14 were female. Nine patients were in stage I meningitis, 12 in stage II, and 33 in stage III. On single variable logistic regression analysis the significant predictors of 6 months outcome of TB meningitis included focal weakness, Glasgow coma scale (GCS), motor evoked potential (MEP) and somatosensory evoked potential (SEP). On multivariable analysis the best set of predictors comprised focal weakness, GCS, and SEP. CONCLUSIONS: In patients with TB meningitis focal weakness, GCS, and SEP are the best predictors of 6 month outcome.  相似文献   
90.
PURPOSE: To present a new technique of ocular fixation to restore and maintain the ocular alignment in primary position for patients with total third nerve paralysis. METHOD: We fixated the globe (medial rectus muscle insertion) to the medial palpebral ligament insertion at the anterior lacrimal crest by using nonabsorbable 5-0 polyester sutures in a prospective study of 5 patients (5 eyes) with congenital total third nerve paralysis. A large recession of the lateral rectus muscle (12 to 16 mm) was also performed in four patients. RESULTS: Four patients achieved satisfactory ocular alignment and one patient had residual exotropia. After an initial exotropic shift, no significant change in ocular alignment was observed during the follow-up period of 6 to 9 months. Mild fullness and congestion over the medial rectus muscle area was observed in the immediate postoperative period in all the patients, which resolved in about two months time. CONCLUSION: This technique of ocular fixation is easy, safe, and effective for the management of exotropia secondary to total third nerve paralysis.  相似文献   
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