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Biomedical subjects

S Tsai

Publications and source records attributed to S Tsai.

At least 91 records · Page 5Linked to original sources

Inverted papilloma of the urinary bladder: report of two cases.

Two cases of inverted papilloma of the urinary bladder are reported. The patients were a 39-year-old male with macrohematuria and a 36-year-old female with interrupted urination. In both of the patients, tumors were resected transurethrally, and histologic examination revealed them to be typical inverted papilloma.

Adult↗

Changes in histone H3 composition and synthesis pattern during lymphocyte activation.

Freshly isolated human lymphocytes were found to synthesize histones at a significant rate even though no DNA was being synthesized. The synthesis pattern of histone variants in resting lymphocytes is similar to that found in other quiescent cells and different from that found in S-phase cells. For this reason, the histone synthesis in resting lymphocytes cannot be attributed to contamination by S-phase cells. Stimulation by the mitogen phytohemagglutinin resulted in a dramatic switch in the histone H3 variant synthesis pattern as well as a readily apparent change in the histone H3 mass pattern. Thus, the chromatin of activated lymphocytes has a different histone H3 variant composition than resting or quiescent lymphocytes. It is suggested that the proportion of H3.3 in the mass pattern of the chromatin of a cell may be related solely to how long that cell has been quiescent. Inducing resting lymphocytes to synthesize DNA by UV irradiation did not qualitatively change the histone variant synthesis pattern. No S-phase H3 variants were induced by the repair process. Furthermore, the quantity of histone synthesized neither increased nor decreased after treatment with UV light.

DNA Replication↗

Giant scrotal hemangioma with azoospermia.

We report a case of giant scrotal hemangioma with azoospermia, which was 37 cm in maximum circumference and 20 cm in length along the raphe. The biopsy specimens of the testes were examined histologically and cytologically. The testicular damage was believed to be due to the heat generated by hemangioma.

Adolescent↗

Familial chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) was previously documented in a father and 4 of his 5 offspring. Follow-up studies revealed spontaneous regression of the disease in 1 patient and shifts in the clinical patterns in the other patients; the unaffected sibling developed lung adenocarcinoma. Cell surface analysis showed that 2 of these patients shared a common surface immunoglobulin profile with mu- and delta-type heavy chains and kappa-type light chains, whereas a 3d sibling with CLL had elevated mu- and kappa-chains. The patient with spontaneous disease remission had a perturbation in the percentage of cells bearing these same markers, consistent with a subclinical persistence of her lympho-proliferative process. Immunogenetic markers were associated with the occurrence of CLL, but these B-cell alloantigens were not linked to HLA. Two patients had abnormalities of chromosome 12 in B- but not T-cells: One had trisomy 12; the other had a mixture of dicentrics and translocations involving the same chromosome.

Aged↗

Patterns of histone variant synthesis can distinguish G0 from G1 cells.

Quiescent Chinese hamster ovary cells, as well as three other types of quiescent cells, synthesize histone at a reduced but significant rate. The variant patterns of the histone synthesis in quiescent, S-phase and G1-phase and G2-phase cells ali differed from each other. H3.3 was the only H3 variant synthesized in quiescent and in G1 and G2 cells. All four H2A variants were synthesized in quiescent and S-phase cells, but only H2A.X and H2A.Z were synthesized in G1 and G2 cells. No part of G1 or the G1-S transition could be found with an H2A synthesis pattern like that in quiescent cells. These findings suggest that the quiescent state is not part of G1, but that it is a separate and discrete state.

Animals↗

Arginine uptake by chick kidney mitochondria.

Arginine uptake by kidney mitochondria in two strains of chicks of high (HA) and low (LA) requirement of dietary arginine was studied by using an ion-exchange method. Dietary factors influencing uptake of arginine were also investigated. The results indicate that arginine uptake by kidney mitochondria of HA chicks was significantly higher than the LA chicks when arginine-deficient diet or diet with excess lysine was fed. The arginine uptake by kidney mitochondria reflects the kidney arginase activity. Both arginase activity and arginine uptake inversely correlated with growth rate of the two strains of chicks. However, the dietary factors that affect kidney mitochondria arginase activity are not completely parallel to the uptake of arginine by kidney mitochondria. A system that facilitates entry of arginine into kidney mitochondrial membrane is suggested.

Animals↗

Prenatal diagnosis of fetal urinary tract abnormalities by ultrasound.

The prenatal detection of renal enlargement and sonolucent "cystic" lesions in 4 fetal abdomens by ultrasound is described. These were later proved to be congenital urinary tract anomalies. Only one of the other 4,628 mothers who had ultrasound gave birth to a child with a congenital urinary tract anomaly that was missed, and 1 fetus was falsely diagnosed as having a congenital urinary tract anomaly based on the ultrasound. Obstruction in the developing urinary tract is associated with renal dysplasia and insufficiency. More experience and improved ultrasonography may enable an accurate diagnosis of urinary tract obstruction; and early relief of the obstruction may be a possible method of management to minimize the renal damage.

Abnormalities, Multiple↗

Response of rats fed diets low in glucose and glucose precursors to low levels of glucose, starch and chemically modified starch.

Several levels of glucose or starches were added to a basal diet that was free of available carbohydrate and low in carbohydrate precursors and fed to male, weanling rats. Rats fed such diets were highly responsive to dietary carbohydrate in growth rate, blood glucose levels and blood ketone bodies. There were no significant differences in the activities of pancreatic amylase, liver glucokinase, glucose-6-phosphatase and fructose-1,6-diphosphatase when dietary carbohydrate varied from 1.5 to 6% of the diet. Under these feeding conditions, a minimum of 6% by weight or 5.8% of the dietary calories has to be provided by carbohydrate to allow the rat an optimum rate of growth. Such diets that are low in glucose precursors were employed as an assay system for glucose availability from chemically cross-bonded starches with various degrees of phosphate crosslinkage. The data showed that introducing low levels of phosphate crosslinkages into the starch had little effect on the glucose availability from the starch.

Animals↗

Clinical manifestations of familial 13;18 translocation.

Female first cousins, aged 21 and 2 1/2 years, with many of the characteristic features of trisomy 18, were found to have identical unbalanced translocations, 46,XX,--13, + der(13)t(13;18) (p13;q12)mat. Clinical features of another cousin, two uncles, and an aunt suggested that they, too, had a partial trisomy 18 phenotype. The long survival and normal menstrual and secondary sexual development in one case are remarkable. A heritable balanced translocation, 46,XX or XY, t(13;18) (p13;q12), was detected in the mothers of the cases, a sib, an aunt, and two uncles. Translocation carriers had abnormalities in gonadal structure or function, with aspermia in males and polycystic ovaries with infertility in several females, suggesting that some gene controlling reproductive development occurs on the long arm of chromosome 18, with normal function interrupted at the breakpoint. Balanced translocation carriers may also be at greater risk for both benign and malignant neoplasms, which included acute leukaemia in an uncle and adenocarcinoma of the stomach at an early age in the grandmother. Although aetiological laboratory studies identified no premalignant state, the clinical findings suggest a defect that may predispose to cytogenetic abnormalities and malignancy.

Adult↗

Sister chromatid exchanges and chromosomes in chronic myelogenous leukemia and cancer families.

Spontaneous sister chromatid exchanges and banded karyotypes were studied in blood lymphocytes from 96 individuals: seven patients with chronic myelogenous leukemia, 15 normal controls, and five "cancer families" comprising 12 cancer patients, 40 tumor-free blood relatives and 22 spouses. The families had: malignant melanoma; Epstein-Barr virus-associated malignancies and a birth defect syndrome; non-Hodgkin lymphoma and diverse carcinomas; Hodgkin's lymphoma and adenocarcinomas; and acute myelogenous leukemia. In addition to the Philadelphia chromosome in chronic myelogenous leukemia patients, karyotypic abnormalities, especially breaks and fragments, were found in 29% of cancer family members, but were inconsistent and usually attributable to radiotherapy. Mean sister chromatid exchange values were normal in chronic myelogenous leukemia, but low (by t-test) in tumor patients and their blood relatives in cancer-prone families. In tumor patients, mean sister chromatid exchange levels fell as age increased. After adjusting for this age effect, no significant differences remained among groups. In patients at high risk of cancer (because they have chronic myelogenous leukemia or a strong family history of cancer), spontaneous sister chromatid exchange rates were not a marker of cancer risk.

Adenocarcinoma↗

Characterization of the continuous, differentiating myeloid cell line (HL-60) from a patient with acute promyelocytic leukemia.

In a prelminary communication, we described the establishment of a continuous human myeloid cell line (HL-60). Here we report the detailed properties of this cell line and document its derivation from the peripheral blood leukocytes of a patient with acute promyelocytic leukemia. As characterized by light and electron microscopy, the predominant cell type in both the fresh and cultured sources is a neutrophilic promyelocyte with prominent nuclear/cytoplasmic asynchrony. Up to 10% of the cultured cells spontaneously differentiate beyond the promyelocyte stage, and the proportion of terminally differentiated cells is markedly enhanced by compounds known to stimulate differentiation of mouse (Friend) erythroleukemia cells. The HL-60 cells lack specific markers for lymphoid cells, but express surface receptors for Fc fragment and complement (C3), which have been associated with differentiated granulocytes. They exhibit phagocytic activity and responsiveness to a chemotactic stimulus commensurate with the proportion of mature cells. As characteristic of transformed cells, the HL-60 cells form colonies in semisolid medium and produce subcutaneous myeloid tumors (chloromas) in nude mice. A source of colony-stimulating activity stimulated the cloning efficiency in soft agar 5--30-fold. Despite adaptations to culture, the morphological phenotype and responsiveness to chemical induction of differentiation is essentially unchanged through at least 85 passages. Cytogenetic studies reveal aneuploidy. Metaphases with 44 chromosomes predominated in vivo and in early culture passages; however, clones with 45 or 46 chromosomes became predominant with continued passaging. The most consistent karyotypic abnormalities were the deletion of chromosomes 5, 8, and X and the addition of a marker resembling a D-group acrocentric and of a submetacentric marker, most likely an abnormal E-group chromosome. No DNA herpesvirus or RNA retrovirus was isolated in the fresh or cultured cells. The HL-60 cultured cell line provides a continuous source of human cells for studying the molecular events of myeloid differentiation and the effects of physiologic, pharmacologic, and virologic elements on this process.

Adult↗

Meal timing dominates the lighting regimen as a synchronizer of the eosinophil rhythm in mice.

Mouse eosinophils undergo circadian fluctuation, and the phasing of the rhythm normally is synchronized to the environmental light-dark cycle if food always is available. This study was undertaken to determine whether or not the same rhythm could be synchronized to restricted feeding schedules. It was found that if food is available ad libitum for only short spans (in this case, 4 h during each 24 h period), the rhythm becomes synchronized to the feeding schedule. In addition, restricting food to certain 4 h spans causes the amplitude of the eosinophil rhythm to increase significantly over that of normal, light-dark synchronized animals. Not all rhythmic variables synchronize to restricted feeding schedules. Some remain synchronized to the light-dark cycle; the phasing of others seems to be the result of an interaction between both the light-dark cycle and the feeding schedule. These studies help dispel the popular misconception that all body functions react in the same manner to different synchronizers and emphasize that one must not generalize about the synchronizing effect of feeding or lighting.

Animals↗

Visualization of surface topology of human lymphoid cells by scanning electron microscopy.

We have studied the surface characteristics of human lymphoid cells with the scanning electron microscope (SEM). We obtained thymic cells by mincing thymus and isolating peripheral blood lymphocytes from normal donors as well as patients with acute and chronic lymphocytic leukemia (ALL and CLL). Prior to SEM, we purified the lymphocytes in isoosmotic Ficoll-Hypaque gradients. In addition, we examined several lymphoid cell lines in permanent culture derived from normal persons, patients with infectious mononucleosis, as well as from patients with ALL. The surfaces of most thymic cells appear smooth with only a few short microvilli. A small number of thymic cells, on the other hand, are found to exhibit many more microvilli of uniform shape and length. We could further identify lymphocytes from normal donors as T- and B-types according to their rosetting spontaneously with sheep red blood cells (SRBC) resemble thymic cells in their surface topology. However, B-cells rosetting with amboceptor--and complement--treated SRBC show greater number of microvilli. The surface morphology of lymphocytes from leukemic patients appears more or less characteristic of the disease type. In contrast, the surfaces of cultured lymphoid cells show a diversified surface topology, often with large smooth areas, very long and very short microcilli, which may often cluster in groups. These data bear directly upon techniques of plasma membrane fractionation and we suspect that the topology differences correlate with their differentiation patterns.

B-Lymphocytes↗

Hopelessness and attempted suicide: a reconsideration.

The authors administered measures of depression, hopelessness, and strength of suicidal intent to a sample of 112 suicide attempters. The results for the 55 subjects diagnosed as depressive and admitted within 72 hours after their attempt were compared with results obtained by Minkoff and associates using comparable measures. Contrary to the findings of the earlier study, there was a lower correlation between hopelessness and intent than between depression and intent. The authors suggest that demographic differences between the two samples may provide explanations for this descrepancy, in the that they reflect the presence or absence of external societal supports that may influence the suicidogenic potential of hopelessness.

Attitude↗