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H H Zhang

Publications and source records attributed to H H Zhang.

25 records · Page 2Linked to original sources
PubMed1997

Clinical significance of negative and equivocal urinary bladder cytology alone and in combination with DNA image analysis and cystoscopy.

BACKGROUND: We evaluated the individual and combined ability of cytology (CYT), image analysis (IA), and cystoscopy (CYSTO) to predict the presence of transitional cell carcinoma (TCC) at 6 months of follow-up in patients with or without a prior history of urothelial carcinoma and negative (NEG) or equivocal (atypical or suspicious) urinary CYT. METHODS: Fifty-one patients (43 with prior TCC) provided 57 urinary samples that were evaluated by CYT and DNA IA. Forty-nine patients were evaluated by CYSTO. Disease status was reassessed at 6 months by a combination of clinical, CYSTO, CYT, and histologic follow-up. RESULTS: At 6 months' follow-up, the incidence of recurrence for patients with diploid, broad diploid, or aneuploid DNA histograms was 38%, 73%, and 100%, respectively. In the same group of patients, 43% of patients with NEG and "atypical" CYT recurred compared with 83.3% of patients with "suspicious" CYT. The predictive value (PV) of a positive (+) CYSTO evaluation was 100%; however, a NEG CYSTO examination was correct in only 73% of cases. Sensitivities of CYT, IA, and CYSTO to predict recurrence were 54%, 59%, and 62.5%, respectively, whereas the combined sensitivity of all three modalities was 72%. The +PV of combined CYT and IA in patients with prior TCC was 90% with aneuploidy 100% specific for malignancy; the NEG PV of combined CYT, IA, and CYSTO was 70%. CYT, IA, and CYSTO were highly significant in predicting recurrence (P = 0.0017, P = 0.0026, and P = 0.0002, respectively) whereas tumor grade and degree of invasiveness as assessed on initial biopsy were not significant. However, 11% of patients recurred between 6 months to 1 year who had NEG CYT, NEG CYSTO, and NEG IA. CONCLUSIONS: Diagnostic accuracy increases in patients with NEG or equivocal CYT if supplemented by DNA IA and CYSTO. In patients with no history of TCC, equivocal urine CYT and/or abnormal DNA IA can occur after chemotherapy, radiation therapy, or viral infection. In these patients, the combined approach together with accurate history is essential for correct diagnosis. For the small subpopulation of patients who recur but demonstrate no abnormalities on combined testing, more sensitive diagnostic tests, such as chromosomal abnormalities by in situ hybridization, need to be developed.

Adult↗
PubMed1993

[Detection of CAg in CSF of 231 cerebral cysticercosis patients].

The results of detection of circulating antigen (CAg) in cerebrospinal fluids (CSF) of 231 cerebral cysticercosis patients with McAb (4F8)--based ELISA were reported and compared with the case histories, clinical manifestations and CT scans. No relationship was found between CAg detected in CSF of these cases and history of taeniasis. However, the positive rate of CAg in cerebral cysticercosis patients with subcutaneous nodules was found significantly higher than those in cases with simple cerebral cysticercosis and in cases with subcutaneous nodules disappeared after anti-Cysticercus therapy before CSF collection. The results of CAg detection in CSF were related with the CT findings as well as the stage of the disease. It is thus indicated that McAb (4F8)-based ELISA might be useful not only for diagnosis of neurocysticercosis, but also for the evaluation of efficacy of anti-Cysticercus therapy.

Adolescent↗
PubMed1993

Cloning of a DNA probe and its application in the detection of Plasmodium falciparum. A preliminary report.

The clones containing parasite DNA fragments were screened from a genomic DNA library of Plasmodium falciparum FCC1/HN isolate. A DNA probe derived from clone pBF4 consisting of 3 kilobase pairs hybridizes specifically with P. falciparum DNA but not with human DNA, P. cynomolgi DNA or P. berghei DNA. The nick translated radiolabelled probe can detect 10 pg purified P. falciparum DNA and a 0.001% parasitemia after 24 hours of film exposure. The probe reacts with all microscopically diagnosed P. falciparum samples and 3 of 41 P. vivax samples as well but not with any of 10 human DNA samples.

Adult↗
PubMed1992

Retention of tissue-specific phenotype in a panel of colon carcinoma cell lines: relationship to clinical correlates.

A panel of eight cell lines has been derived from colon carcinomas. These cell lines have both been characterized according to standard criteria of growth rate, response to mitogens (epidermal growth factor and basic fibroblast growth factor), xenograft growth and growth in soft agar, and according to the ability of the cells to express epitopes known to be expressed by cells in the normal intestinal mucosa. The expression of epitopes present in columnar (absorptive) cells has been assessed using a panel of monoclonal antibodies to brush border peptidases and disaccharidases, villin and brush border-specific peptides. Goblet cell epitopes have been determined by monoclonal antibodies to mucin and carcinoembryonic antigen. An antibody to chromogranin was used to identify endocrine cells. Using these antibodies we found that all the cell lines reacted with at least one of the antibodies to columnar cells. Similarly, varying proportions of cells in six of the eight cell lines stained with antibodies to mucin. None of the cells expressed chromogranin. Expression of a differentiated colonic phenotype, as measured from antibody staining, did not correlate with measurements of malignancy, such as the ability of the cells to grow in soft agar or as xenografts. Similarly, there was no correlation between retention of a colonic phenotype and the initial pathological stage of the tumour from which the cell lines were derived.

Animals↗
PubMed1992

A MAb-based ELISA for detecting circulating antigen in CSF of patients with neurocysticercosis.

A monoclonal antibody (MAb)-based enzyme-linked immunosorbent assay (ELISA) was evaluated for detecting circulating antigen (CAg) in the cerebrospinal fluid (CSF) of patients with neurocysticercosis. CAg of Cysticercus Cellulosae was detected in 95 out of 116 patients with neurocysticercosis. Of the 21 neurocysticercosis patients in whom CAg was not detected, 14 had only higher density spots, 3 had one or two lower density spots and 4 had no obvious damage in their brain Computed Tomography (CT) scans. CAg was also not detected in CSF samples of patients with other diseases of the central nervous system. These included cerebral tumor, encephalopyosis, brain trauma, viral meningitis and cerebral hemorrhage. Detecting CAg with MAb-based ELISA is better than any previously available methods for the diagnosis of active neurocysticercosis.

Animals↗
PubMedDate not supplied

Overexpression of cyclooxygenase-2 correlates with tumor angiogenesis in endometrial carcinoma.

The inducible enzyme cyclooxygenase-2 (COX-2) is an important mediator of angiogenesis and tumor growth. Several reports have indicated that vascular endothelial growth factor (VEGF)-positive tumors are associated with an increased amount of COX-2 protein. This study evaluated the significance of COX-2 in 34 patients with endometrial carcinoma and its relationship to angiogenesis. Immunohistochemical expression of COX-2 and VEGF was analyzed on paraffin-embedded tissue sections. Microvessel density (MVD) of endometrial carcinoma was also determined with anti-CD(34) as the label. COX-2 messenger RNA (mRNA) was analyzed by reverse transcription-polymerase chain reaction. The expression rate of COX-2 in 34 cases was 64.7% but not in control endometrium. COX-2 mRNA was higher in tumor specimens than in normal tissues. The level of COX-2 expression was higher in grade 2 tumors than in grade 3 tumors (P < 0.05). MVD was higher in COX-2-positive and VEGF-positive cases than in COX-2-negative and VEGF-negative cases (P < 0.05). The expression of COX-2 was positively correlated with the expression of VEGF and MVD (P < 0.05 and P < 0.01, respectively). The present findings suggest that overexpression of COX-2 may induce the expression of VEGF, increase angiogenesis, and enhance tumor growth.

Adult↗