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Biomedical subjects

U Kim

Publications and source records attributed to U Kim.

At least 91 records · Page 5Linked to original sources
PubMed1982

Free amino acid pools of rodent mammary tumors.

Intracellular pools of free amino acids were compared individually in mammary tumors of Wistar Furth and Sprague-Dawley rats and C3H and DBA/2 mice. Of 11 transplantable and 7,12-dimethylbenz[a]anthracene-induced adenocarcinomas of the rat, all nonmetastasizing tumors could be distinguished from metastasizing tumors by the accumulation of high glutamine pools and significant-to-high cystathionine pools. In primary mammary tumors of C3H mice and transplanted mammary tumors of DBA/2 mice, intracellular free arginine was frequently below that of the circulating plasma level and approached that in the arginine-destroying organ, the liver. Arginine pool depletion was also noted in normal mammary tissue, particularly in the actively lactating mouse. Individual rat or mouse mammary tumors also contained high levels of taurine, beta-alanine, and gamma-aminobutyric acid, which, like cystathionine, are distinctive for or are enriched in neural tissue. None of these pool enrichments were characteristic of normal rat or mouse mammary tissue. Free hydroxyproline was low in primary induced rat mammary tumors and higher in transplanted mammary tumors and in normal lactating mammary glands, particularly in the mouse. In contrast, the hydroxyproline residues of collagen, taken as an index of mesenchymal cell contribution, were very low in all tumors.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1982

Androgen control of cytosol progesterone receptor levels in the MT-W9B transplantable mammary tumor in the rat.

The effect of androgen on the levels of the cytosol progesterone receptor was examined in the transplantable rat mammary tumor MT-W9B and in the normal uteri of inbred WF rats. Progesterone receptor levels were barely detectable in tumors grown in male WF rats but were increased after castration or administration of 17 beta-estradiol. Both effects were blocked by testosterone. In tumors grown in intact female rats, both testosterone and dihydrotestosterone decreased progesterone receptor levels in a dose-dependent manner, and testosterone completely blocked the estradiol-induced increase in progesterone receptor levels in tumors from ovariectomized rats. The inhibitory effect of testosterone in female rats was blocked by the antiandrogen flutamide, suggesting an androgen receptor-dependent mechanism. Neither dihydrotestosterone nor testosterone had any effect on basal levels of progesterone receptor in tumors from ovariectomized rats. In uterus, up to 5 mg dihydrotestosterone/kg did not affect progesterone receptor levels, and a dose of 5 mg/kg was also uterotropic. This fact plus the finding that testosterone only partially blocked the estradiol-induced increase in uterine progesterone receptor levels suggested stimulation of different cell types by testosterone and estradiol. This did not appear to be the case in the tumor, however. Androgen is suggested to act as a negative modulator of progesterone receptor levels, which might have clinical relevance in terms of hormone therapy of breast cancer.

Androgens↗
PubMed1981

Squamous cell carcinoma in dominant type epidermolysis bullosa dystrophica.

The unusual genetic disorder epidermolysis bullosa dystrophica has been reported in several patients in whom the chronic cutaneous scars led to the development of cutaneous squamous cell carcinoma. However, only one of these previously reported cases involved the autosomal dominant form of the disease; the remainder occurred in its recessive counterpart. We report the second and third patients with squamous cell carcinoma associated with the dominant form of epidermolysis bullosa dystrophica. In addition, we not only observed the previous electron microscopic findings of decreased numbers of anchoring fibrils beneath the basal lamina but have also noted marked disruption of the basal lamina itself.

Carcinoma, Squamous Cell↗
PubMed1981

Dietary selenium intake and growth of the MT-W9B transplantable rat mammary tumor.

The present study reports the effect of dietary selenium deficiency and supplementation on the growth of the transplantable MT-W9B mammary tumor in female Wistar-Furth rats. Supplementation of the diet with 2 ppm of selenium inhibited tumor growth and reduced the final tumor weight by approximately 50% compared to the control rats receiving 0.1 ppm of selenium. The inhibitory response was selective, without inducing any weight loss in the animals. On the other hand, selenium deficiency (less than 0.02 ppm) had no influence on the growth of this tumor.

Animals↗
PubMed1981

Dichotomous effects of tamoxifen on a transplantable rat mammary tumor.

The effect of the antiestrogen tamoxifen on growth of the transplantable autonomous mammary tumor MTW-9B was compared with its effects on progesterone and estrogen receptor levels. Growth of the tumor was similar in intact rats, ovariectomized rats, or ovariectomized rats given estradiol, in both the presence and the absence of tamoxifen. Progesterone receptor levels, however, were reduced by ovariectomy and restored by estrogen administration. Tamoxifen antagonized this effect of estrogen, although when administered by itself to ovariectomized rats it acted as an agonist, since progesterone receptor levels were induced. Cytosol estrogen receptor was depleted by tamoxifen in both intact and ovariectomized rats. In uterus from the same animals, tamoxifen also showed both antagonist and agonist properties, although here too there was an apparent dissociation between effects on growth and progesterone receptor levels. We conclude from these experiments that: (a) the estrogen receptor complex may be acting at more than one site on the genome; and (b) regulation of progesterone receptor levels by estrogen (or tamoxifen) does not necessarily predict sensitivity of tumor growth to antiestrogens.

Animals↗
PubMed1980

Appraisal of aspiration cytology in management of Hodgkin's disease.

The value of aspiration cytology in the management of Hodgkin's disease is shown in this study of 228 patients and 403 aspirations; 385 from lymph nodes and 18 from extranodal masses. In all patients the initial diagnosis was established on surgical biopsy. Aspirates were helpful in staging, defining extension of unusual radiation fields, and in recognizing residual disease and relapses after therapy. Adequate material was obtained in 80% of aspirations. The diagnosis of Hodgkin's disease could not be established in the adequate cytologic sample in 9.9% of cases. In 5.5%, the diagnosis was that of benign reactive hyperplasia and in 4.4%, non-Hodgkin's lymphoma. Unsatisfactory material was usually obtained from nodes less than 1 cm in diameter or from residual lesions following radiation or chemotherapy. Only 14 of 93 such lesions proved to have active disease during follow up. There were no significant complications. Characteristics of the varied aspects of aspirated tumor cells found in Hodgkin's disease are described.

Adolescent↗
PubMed1980

Splenic T and B lymphocytes and their mitogenic response in untreated Hodgkin's disease.

The splenic T and B cell distribution in 79 patients with untreated Hodgkin's disease was quite similar to that in 15 control patients with non-Hodgkin's lymphoma or carcinoma. The mean T lymphocyte percentage was slightly higher in involved spleens than in uninvolved spleens of patients with Hodgkin's disease. There was no significant difference in the T and B cell distribution between tumor area and tumor-free area of the same spleens of Hodgkin's disease patients. Splenic T and B cell distribution did not correlate well with the clinical features of Hodgkin's disease. The splenic T cell percentage was significantly lower than that of the peripheral blood T cell percentage (P less than 0.05), while the splenic B cell percentage was significantly higher than peripheral blood B cell percentage (P less than 0.01) in 13 patients with untreated Hodgkin's disease. The splenic T lymphocyte response to PHA was significantly higher than the peripheral blood T lymphocyte response (P less than 0.05), and the splenic B lymphocyte response to PHA, in the presence of irradiated autologous splenic T lymphocytes, was also significantly higher than the peripheral blood B lymphocyte response (P less than 0.05) in 8 and 6 patients with untreated Hodgkin's disease, respectively. Since the control splenic cells, utilized in this study were obtained not from patients with non-neoplastic disease, but from patients with neoplastic disease other than Hodgkin's disease, our data are not conclusive, but only suggestive of normal T and B cell distribution and function in uninvolved spleens of patients with untreated Hodgkin's disease.

Adolescent↗
PubMed1980

Optimal timing of surgical intervention in patients with acute pancreatitis associated with cholelithiasis.

In evaluating patients with acute pancreatitis, disproportionately high serum amylase values in comparison to physical findings of peritonitis of the upper part of the abdomen and the rapid return to normal values and the lack of a history of alcohol ingestion should be viewed as findings highly indicative of pancreatitis associated with cholelithiasis. Diagnostic roentgenologic procedures can be initiated soon after admission of the patient, with an intravenous cholangiogram or oral cholecystogram, depending upon the feasibility of oral intake, in patients without jaundice. Expectant treatment is both safe and preferable, so that surgical treatment for disease of the biliary tract is performed after the diagnosis is established in the same hospitalization period.

Acute Disease↗
PubMed1979

Oral amphotericin for candidiasis in patients with hematologic neoplasms. An autopsy study.

Autopsy examinations were conducted in 72 patients with hematologic malignant neoplasms who received antibacterial therapy before their deaths. These patients were participants in a large double-blind study designed to assess the efficacy of oral amphotericin B in decreasing the incidence of candidal infection. The patients received either 50 mg of amphotericin B orally four times a day, or they received a matching placebo. Eight of 33 patients (24%) who had received placebo and two of 39 (5%) who had received amphotericin had histopathologic evidence of disseminated candidiasis. We conclude that in these patients with hematologic malignant neoplasms who received antibiotics within two weeks of death, the concomitant oral administration of amphotericin was effective in decreasing the incidence of systemic candidal infections, indicating that the gastrointestinal tract serves as a portal of entry for Candida albicans.

Administration, Oral↗
PubMed1979

Mammary cancer: selective action of the estrogen receptor complex.

Progesterone receptors in the autonomous rat mammary tumor MTW-9B are reduced 80 to 90 percent after ovariectomy, but are not reduced if ovariectomized animals are given estrogen. Tumor growth, however, is independent of estrogen status and insensitive to pharmacological doses of estradiol. This represents an unusual system characterized by a selective action of an inducing agent on the genome.

Animals↗
PubMed1979

Explorations of antimitotic agents in the treatment of a congenital disease, ichthyosis linearis circumflexa.

Successful therapy of a genetic disorder, Ichthyosis Linearis Circumflexa, was achieved using a low dose systemic cyclophosphamide. Prior to such therapy, 80 to 90% of the body surface was affected; the use of antimitotic agents reduced the extent of the lesions to less than 15% of the body surface. As a result, the clinical status was changed from severely disabling to being compatible with a normal way of life. It is believed that this phenomenon is related to selective effects of cyclophosphamide, such as those on lymphocyte subpopulations. To our knowledge, successful chemotherapy for diseases of genetic or congenital origin has not been previously reported.

Adult↗
PubMed1979

A tumor-associated organ-specific antigen characteristic of spontaneously metastatic rat mammary carcinomas.

An organ-specific tumor-associated antigen (TAA) was present in several metastatic and nonmetastatic mammary carcinomas induced in WF female rats by 3-methylcholanthrene. The level of TAA was high in 2 metastatic carcinomas tested (TMT-081 and SMT-2A) and much lower--by a factor of 50--200--in 2 nonmetastatic mammary carcinomas (MT-100 and MT-W9B). The TAA in the 2 metastatic tumors was identical, as demonstrated by immunodiffusion and supported by cross-reactivity with antibody against TAA from TMT-081 in a binding inhibition radioimmunoassay. The TAA was shed in relatively large amounts by the metastatic tumors maintained in short-term organ culture. The high level and shedding of TAA thus appeared to be characteristics of the metastatic tumors but not of the nonmetastatic ones. This suggests that TAA on the cell membrane or in the circulation may be involved in the metastatic process as a factor blocking potentially cytotoxic cells or in other ways leading to suppression of the immune response against the tumor.

Animals↗
PubMed1978

Fucosyltransferase activity in metastasizing and nonmetastasizing rat mammary carcinomas.

Fucosyltransferase levels in 6 established strains of spontaneously metastasizing rat mammary tumors (STMT-058, MT-449, DMBA-4, SMT-077, TMT-081, and SMT-2A) were compared with 4 nonmetastasizing strains (MT-W9B, MT-W9A, MT-100, and MT-66) as controls. Two acceptors were prepared from fetuin for the assay, one by acid hydrolysis of N-acetylneuraminic acid and the other by the stepwise removal of N-acetylneuraminic acid and penultimate galactose by Smith degradation. The enzyme that transfers fucose to the first acceptor was designated fucosyltransferase A, whereas the one that uses the second acceptor was designated fucosyltransferase B. Both types of fucosyltransferases were found in this rat mammary tumor system. Whereas the levels of fucosyltransferase A in the 2 tumor groups were comparable, those of fucosyltransferase B were sixfold to sevenfold higher in the metastasizing tumors. This difference in the level of fucosyltransferase B was not caused either by differential hydrolysis of GDP-fucose by pyrophosphatase in the 2 groups or by hydrolysis of the product by fucosidases. Presence of any other inhibitor(s) or activator(s) of fucosyltransferase was excluded by mixing experiments. Optimal conditions for the assay of this enzyme were determined in a representative strain from each group. Under all circumstances, the activity of fucosyltransferase B was higher in the metastasizing tumors. The enzyme was inhibited by nucleoside diphosphates and triphosphates, and guanosine nucleotides were the most efficient inhibitors. Subcellular distributions of the two fucosyltransferases were similar, 35-50% of the enzyme activity being present in the crude microsomes. When plasma membrane factions were prepared from the microsomes, the major part (50-70%) of the enzyme was associated with the light and heavy plasma membrane fractions. Increased activity of fucosyltransferase B in the group of metastasizing tumors may have reflected faster synthesis and shedding of fucose-containing glycoprotein antigens. Similar molecules possibly were also synthesized in the nonmetastasizing cells but at a much slower rate, because the antigen is not easily lost from the cell surface. Any alteration of the specificity of this focosyltransferase in the metastasizing tumors, in addition, may have caused antigen modulation.

Adenosine Triphosphate↗
PubMed1978

Cystosarcoma phyllodes metastatic to the pancreas.

A case is presented of cystosarcoma phyllodes of the breast metastatic to the pancreas. Solitary metastasis to the pancreas has not been reported. The lesion was excised in toto with a good result. Clinical and pathological features of cystosarcoma phyllodes are discussed.

Breast Neoplasms↗