Biomedical subjects
Publications and source records attributed to C Hsu.
Retroperitoneal sarcoma can occur in the female pelvis and be confused with other pelvic masses. Its diagnosis depends on an awareness of its occurrence. Aggressive surgery to completely excise the tumor determines survival.
Uptake of 22Na+ and 45Ca2+ into everted membrane vesicles from Escherichia coli was measured with imposed transmembrane pH gradients, acid interior, as driving force. Vesicles loaded with 0.5 M KCl were diluted into 0.5 M choline chloride to create a potassium gradient. Addition of nigericin to produce K+/H+ exchange resulted in formation of a pH gradient. This imposed gradient was capable of driving 45Ca2+ accumulation. In another method vesicles loaded with 0.5 M NH4Cl were diluted into 0.5 M choline chloride, creating an ammonium diffusion potential. A gradient of H+ was produced by passive efflux of NH3. With an ammonium gradient as driving force, everted vesicles accumulated both 45Ca2+ and 22Na+. The data suggest that 22Na+ uptake was via the sodium/proton antiporter and 45Ca2+ via the calcium/proton antiporter. Uptake of both cations required alkaline pHout. A minimum pH gradient of 0.9 unit was needed for transport of either ion, suggesting gating of the antiporters. Octyl glucoside extracts of inner membrane were reconstituted with E. coli phospholipids in 0.5 M NH4Cl. NH4+-loaded proteoliposomes accumulated both 22Na+ and 45Ca2+, demonstrating that the sodium/proton and calcium/proton antiporters could be solubilized and reconstituted in a functional form.
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Various parameters of copulatory behavior were examined in intact and castrated testosterone-(T-)treated male rats of various ages ranging from 3 to 27 months. Serum T levels were controlled by subcutaneous implantation of different sizes of T-filled Silastic capsules at the time of castration. In intact male rats, scores of various parameters of copulatory behavior declined gradually from middle age and no ejaculation was observed in any rats over 22 months of age. When serum T levels were maintained at 0.78-0.87 ng/ml for 6 months from 4 months of age, these rats showed the same copulatory activity as intact rats, except that fewer rats exhibited ejaculation at 8 and 10 months of age and showed decreased total mount frequency at 10 months of age. Even when serum T levels were maintained at 2.95-3.53 ng/ml for a period of 6 months from 18 months of age, copulatory activity still declined gradually and no rats over 22 months of age ejaculated. However, long-term elevation of serum T level could prevent further decline of intromission frequency in old age. These results indicate that the copulatory activity of male rats in response to circulatory T declined with advancing age and that prolonged low levels of serum T had only a minor role in the onset of decreased responsiveness of neural male sexual behavior.
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The purposes of this study were to investigate (1) the relationship between estrogen and glucose levels in the circulation during an estrous cycle of the rat and (2) the effect of estrogen on the hyperglycemic action of alloxan. Three-month old Long Evans strain rats were used. The present study established for the first time the correlation between estrogen and glucose levels in the circulation during an estrous cycle. A significant (p less than 0.01) negative correlation was observed with the lowest glucose level at the proestrus stage where estrogen is at peak. The severity of hyperglycemia induced by alloxan was positively correlated with the circulating level of endogenous estrogen, but was negatively correlated with the fasting glucose level. A similar pattern was observed in ovariectomized female rats that were followed by estradiol implantation to achieve a constant level of circulating estrogen. It may be concluded from the present study that estrogen, under physiological conditions, participates in the regulation of glucose metabolism during various stages of the estrous cycle in the rats, and that glucose is likely able to protect the pancreatic beta cells of the animals against the hyperglycemic action of alloxan.
Twelve patients with cervical intraepithelial neoplasia (CIN) were studied by colposcopy and cervical smears to elucidate the local response to interferon alpha and beta given by perilesional injections and to assess long-term disease remission. In all patients, local inflammatory response was seen and persisted throughout the treatment period. Selective toxic effect was evident by exfoliation of increasing proportion of degenerate to viable dyskaryotic cells, while the normal epithelial cells appeared unaffected, and by the progressive regression of the lesion. Interferon alpha induced complete remission in six of seven (85.7%) patients but three had recurrence 12 to 24 months later, while interferon beta induced complete remission in only two of five (40%) patients.
Leukocyte interferon gel (1 X 10(6) units) was applied twice daily by a vaginal applicator to areas of cervical intraepithelial neoplasia (CIN) in 7 patients. A partial response was obtained in 3 patients and complete response in 2 patients. This suggests that leukocyte interferon gel can be used to treat CIN.
The sequence of Lyt-2 cDNA shows that it is a new member of the immunoglobulin super gene family. Analysis of the predicted amino acid sequence indicates that the Lyt-2 polypeptide is synthesized with a 27-amino acid leader, and that the mature protein has an immunoglobulin variable region (Ig V)-related sequence of approximately 100 amino acids, an extracellular spacer of 43, a transmembrane region of 38, and an intracytoplasmic region of 27 amino acids. Lyt-2 and its human analogue Leu-2 are 56% homologous; analysis indicates that the Ig V-related domains of the two molecules have evolved away from each other faster than the carboxyl-terminal half of the proteins.
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Eighty-nine patients with postmenopausal uterine bleeding were studied focusing on the nonorganic causes of bleeding. Atrophic endometrium was found in 82%, proliferative endometrium in 7%, and secretory endometrium in 1% of patients. Carcinoma was uncommon, found in only 7% of patients. Hysteroscopy was an invaluable adjunct to dilatation and curettage in diagnosing bleeding due to atrophic endometrium as 42% of such cases yielded no tissue on curettage. The clinical entity of bleeding atrophic endometrium is discussed.
From January 1976 - end of 1979, 427 patients with cervical cancer were treated in the Department of Gynaecology, University of Hong Kong. Twenty-seven (6%) had primary adenocarcinoma of cervix. Eighteen patients with stage I and early stage II were treated by preoperative irradiation and Wertheim hysterectomy. Serial cervical biopsies were taken to assess the response to radiotherapy. All the cervical biopsies as well as the surgical specimens were read by the same pathologist. 83% showed residual dividing tumour cells in the surgical specimens. One hundred and forty-five patients with early squamous cervical cancer were similarly treated during the same period; only 13% had residual tumour in the specimens (chi square test p is less than 0.001). All the patients are being followed up regularly. Fifteen patients with early cervical adenocarcinoma are free from disease. The shortest period of follow-up is 5 1/4 years.
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In order to facilitate cloning of genes for cell surface molecules, we cotransfected LTK- mouse fibroblasts with thymidine kinase (TK) genes and total human or mouse DNA. TK+ cells, selected by growth in HAT medium, were stained with fluorochrome conjugated monoclonal antibodies or other fluorescent ligands which bind to one or another membrane differentiation antigen or receptor. We isolated fluorescent transfectants expressing these molecules using a fluorescence activated cell sorter (FACS). For some antigens, spontaneous gene amplification occurred. By repeated cycles of FACS sorting and regrowth we obtained high expressing clones. We then isolated cDNA and genomic clones using selected cDNA probes to screen phage with cDNA inserts. DNA from virtually any tissue source transfected equally well for the various molecules except for DNA from a trophoblast derived choriocarcinoma cell line which did not transfect for Leu-2.
Ninety-four patients with invasive carcinoma of the cervix were investigated for radio-response during treatment using colposcopy and serial biopsies. In 31 patients, the results were further correlated with pathological examination of the Wertheim hysterectomy specimen. It is established that colposcopy can be as reliable as biopsy in predicting radio-response and can be employed complementary to serial biopsies and clinical examinations. The colposcopic features of cervical carcinomas undergoing irradiation are described.
Unusual extracellular birefringent laminated ovoid structures are seen in bronchial brushing, aspiration, and washing specimens in a 28-year-old woman who had histologic evidence of pulmonary talcosis. Energy dispersive x-ray analysis and microchemical studies have identified them to be calcium carbonate. These structures are known as pulmonary blue bodies and are seen mainly in histologic paraffin sections. Their occurrence in cytologic preparations and association with talcosis have not been reported.
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A case of sclerosing stromal tumor of the ovary in a Chinese girl of 17 years is reported. She presented with metrorrhagia and an abdominal mass in the right lower quadrant. At operation, a large unilocular cyst was found in the right ovary. Light microscopic and ultrastructural study established the diagnosis of sclerosing stromal tumor of the ovary. To date, 63 cases have been recorded in the literature, 33 of which have been described in detail.