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Biomedical subjects

W R Hein

Publications and source records attributed to W R Hein.

64 records · Page 4Linked to original sources
PubMed1988

Flow and composition of lymph from the ovary and uterus of cows during pregnancy.

Ovarian or uterine lymph was collected continuously for periods of up to 25 days from 16 cows cannulated at stages of pregnancy ranging from 96 to 278 days post coitum. Blood samples were taken acutely from the ovarian and uterine veins during surgery and periodically from the jugular vein during the course of lymph collection. The flow rate and cell content of lymph was measured and blood and lymph plasma samples were analysed for progesterone, pregnenolone, pregnenolone sulphate, androstenedione, testosterone, oestrone, oestrone sulphate, oestradiol-17 beta, prostaglandin (PG) F-2 alpha, total protein and albumin. There was a high flow rate of protein-rich lymph from luteal ovaries with rates up to 101.7 ml/h occurring in individual lymphatics over short periods. Peripheral ovarian and uterine lymph contained a low concentration of cells (mean less than 10(5) cells/ml) comprising about 82-87% lymphocytes, 11-14% macrophages and monocytes and 2-4% other cells. At all stages of pregnancy, the concentration of progestagens and androgens was higher in ovarian lymph than in uterine lymph or blood plasma. The differences were greatest for progesterone and androstenedione which occurred at 200-fold and 60-fold greater concentration respectively in ovarian lymph than in jugular plasma. When serial 10 min samples were collected over a 12-h period, the concentration and output of progesterone in ovarian lymph varied in a phasic manner, ranging from 3.5 to 7.6 microM and from 31.7 to 293.1 nmol/h respectively. There was a positive correlation between the output of progesterone in lymph and the progesterone concentration in jugular blood samples taken every 20 min. During most of pregnancy there was little difference between the concentration of oestrogens in ovarian lymph, ovarian venous plasma and jugular plasma but, during the 3-5 days before calving, these hormones occurred at slightly higher concentration in ovarian lymph. Apart from pregnenolone and androstenedione, all steroids occurred at lower concentrations in uterine lymph than in jugular plasma. Shortly before parturition there was an abrupt increase in the concentration of PGF-2 alpha in uterine lymph. Lymph reflects more accurately the milieu of tissue cells than efferent blood and further analysis of differences in the concentration of substances in lymph relative to the output in the ovarian and uterine arterial and venous blood may lead to the identification of factors important in local regulatory mechanisms in the reproductive tract.

Androgens↗
PubMed1988

Traffic and proliferative responses of recirculating lymphocytes in fetal calves.

The thoracic duct or efferent prescapular duct was cannulated in four fetal calves aged 121-259 days post-conception. The duration of lymph flow ranged from 2 to 20 days and the mean flow rates sustained over these collection periods varied from 5.4 to 48.8 ml/hr. Lymphocyte output ranged from 4.4 x 10(6) cells/hr in thoracic duct lymph from a 121-day fetus to 3.9 x 10(8) cells/hr in efferent prescapular lymph from a 259-day fetus. The circulating lymphocyte pool in fetal calves of about 120 and 190 days gestational age was calculated to contain, respectively, 4 x 10(8) cells and 2 x 10(10) cells. The proportion of lymphocytes bearing surface immunoglobulin detected in fetal lymph ranged from 2.1% to 8.7%. Recirculating lymphocytes from fetal calves produced strong proliferative responses when stimulated by T-cell mitogens but responded poorly to B-cell mitogens. Fetal lymphocytes also responded to stimulation by allogeneic cells and stimulated other cells to proliferate during mixed lymphocyte culture. When stimulated with Con A, fetal lymphocytes secreted IL-2 to a degree that was indistinguishable from the secretory behaviour of lymphocytes from adult animals. The results presented in this paper show that chronic lymphatic fistulae can be established successfully in fetal calves to give access to recirculating lymphocytes. This provides a new experimental approach for studying the development of the bovine immune system.

Animals↗
PubMed1988

Analysis of cell division among subpopulations of lymphoid cells in sheep. I. Thymocytes.

The number, distribution and surface phenotype of dividing cells in the thymus, and differences between the cell cycle status of thymocyte subpopulations, were studied in fetal and post-natal lambs using double-labelling techniques. Dividing cells were labelled in vivo for various periods with 5-bromo-2-deoxyuridine (BrdU). The proportions of constituent thymocyte subpopulations that had synthesized DNA during the labelling period were measured by flow cytometry or immunohistochemistry using a panel of monoclonal antibodies (mAbs) specific for sheep lymphocyte differentiation antigens and MHC class I and class II antigens in conjunction with an anti-BrdU mAb. The proportion of thymocytes that incorporated BrdU during a 1-hr labelling period varied with age, and levels of 30%, 13% and 9% were measured, respectively, in 40- and 125-day-old fetuses and 8-week-old lambs. Eight percent of the thymocytes in lambs were synthesizing DNA, with 4% entering the G2 phase per hour, and a substantial number of thymocytes (21%) had a G2 + M phase DNA content. A small subset of thymocytes (1-3%) recognized by mAb E-79 localized to the subcapsular region of the cortex and displayed the highest level of BrdU incorporation. Cortical-type thymocytes (CD1+) comprised 50-70% of thymocytes; however, few of these incorporated BrdU and the proportion in the G2 + M phase of the cell cycle was higher than for other thymocyte subpopulations. The 197+CD4-CD8- T cells also showed no evidence of in vivo division.

Animals↗
PubMed1988

Analysis of cell division among subpopulations of lymphoid cells in sheep. II. Peripheral lymphocytes.

The number, distribution and surface phenotype of dividing cells in lymph nodes and blood and differences between the cell-cycle status of lymphocyte subpopulations were studied in lambs using double-labelling techniques. Dividing cells were labelled in vivo for various time periods with 5-bromo-2-deoxyuridine (BrdU). After removal of lymphoid tissues, the proportions of constituent lymphocyte subpopulations which had synthesized DNA during the labelling period were measured by flow cytometry or immunohistochemistry using a panel of monoclonal antibodies (mAbs) specific for sheep lymphocyte differentiation antigens and MHC class I and class II antigens in conjunction with an anti-BrdU mAb. There was a higher overall level of cell division in the ileocaecal lymph node than in either the prescapular or parathymic lymph nodes. In all three lymph nodes, the majority of lymphocytes which incorporated BrdU occurred in B-cell follicles or germinal centers. CD4+ and CD8+ T cells had a higher level of cell division (LI 5-14%) than those recognized by mAb 197 (CD4- CD8- subset) (LI less than or equal to 3%).

Animals↗
PubMed1988

Effect of interferon-alpha-2a on the output of recirculating lymphocytes from single lymph nodes.

The output of recirculating lymphocytes from cannulated popliteal lymph nodes in sheep was measured after administration of human recombinant interferon (rIFN)-alpha-2a. Interferon (IFN) injection caused a dramatic decrease in lymphocyte output from lymph nodes. Following a single s.c. or i.d. injection of 2 x 10(7) U IFN into the drainage area of the popliteal lymph node, lymphocyte output fell to below 1% of the pre-treatment level and remained depressed for up to 35 hr. A substantial decrease in lymphocyte output from cannulated nodes also occurred after IFN was injected either i.v., into the skin of the opposite non-cannulated hind leg or into an afferent lymphatic vessel leading to the popliteal lymph node. After the period of depressed lymphocyte output, a seemingly compensatory surge of cell traffic occurred that lasted 2-3 days. During this phase there was a relative increase in the proportion of CD4+ T cells in lymph. Similar changes occurred after each treatment in animals given multiple doses of IFN. These effects are unlikely to be antigen-induced since there was no blast cell response in any treated animal. The analysis of blood and lymph plasma samples showed that the most severe depression of lymphocyte output was associated with high levels of IFN, while there was no apparent correlation between the reduction in lymphocyte traffic and concentrations of cortisol in plasma. These results suggest that IFN-alpha-2a is involved directly in the regulation of lymphocyte output from lymph nodes.

Animals↗
PubMed1987

Cellular composition of peripheral lymph and skin of sheep defined by monoclonal antibodies.

The surface phenotype of cells in peripheral lymph collected from afferent lymphatics leading to the popliteal lymph node of sheep was determined using a panel of monoclonal antibodies (mAbs). The majority of lymphocytes (83.5%) expressed the sheep pan-T cell antigen and only 13.3% bore surface immunoglobulin molecules. All peripheral T cell subsets occurring in sheep were detected; 50.2% of lymphocytes were positive for mAb SBU-T4 (T helper), 7.3% were positive for mAb ST-8 (T cytotoxic), and 8.4 and 43.0% expressed T subset markers recognized by mAbs 197 and T-80, respectively. Major histocompatibility complex (MHC) class I antigens were detected on 71.1% of lymphocytes and MHC class II antigens on 21.8%. The macrophage/veiled cells found in peripheral lymph did not express lymphocyte subset markers but were positive for MHC class I and II antigens, the sheep homologue of T6 antigen, leukocyte common antigen and mAb 175 (myeloid/erythroid). Macrophage-like cells occurring in the epidermis of skin taken from the lower hindleg gave positive staining reactions to the same mAbs which stained the macrophage/veiled cells in peripheral lymph. These results illustrate differences between the migration of lymphocyte subsets through nonlymphoid as compared to lymphoid tissues and point to a possible developmental or migratory relationship between the macrophage-like cells in skin and those in afferent popliteal lymph.

Animals↗
PubMed1981

Evaluation of the NASA/JSC blood pressure screening clinic.

This study evaluated the NASA/Johnson Space Center's blood pressure screening program, which was designed to identify the proportion of NASA employees who were hypertensive and to identify self-report variables related to elevated pressures. In 1978, a random sample of 3892 employees was selected from over 2,100 NASA employees. Twenty-eight percent were classified as hypertensive by the criterion of systolic pressure of 140 or above or diastolic pressure of 90 or greater. Approximately 16% of all employees had a history of hypertension; the remaining 12% of the identified hypertensives were unaware of their potential health problem. Multivariate analysis showed that elevated systolic pressures were more prevalent in the older, heavier employees. Of hypertensives under treatment, about 74% were under poor control as judged from blood pressures randomly taken at their place of employment. These results demonstrated the effectiveness of screening for unsuspecting hypertensives in industry.

Adult↗
PubMed1981

An abattoir survey of tuberculosis in feral buffaloes.

Tuberculosis lesions were found in 193 (1.7%) of 11,322 buffaloes examined during routine post-mortem inspection at 2 export abattoirs. The prevalence of tuberculosis in buffaloes supplied from 17 separate farms ranged from 0.3% to 8.22%, with the highest levels occurring on the coastal plains. Lesions were confirmed to one major body region in 50 of 72 randomly chosen cases of tuberculosis and to 2 or more regions in 22 cases. Thoracic lesions occurred in 65 of the 72 cases, abdominal lesions in 19, head lesions in 18 and carcase lesions in 9. In the thoracic cavity, lesions occurred most frequently in mediastinal and bronchial lymph nodes. In the head region the retropharyngeal lymph node was most frequently involved, in the abdominal cavity, the liver, and in the carcase, the deep inguinal lymph node. Tuberculosis lesions in buffaloes had a lardaceous consistency and were paler in colour and less calcified than those normally exhibited by cattle. Mycobacteria were isolated from 30 to 31 lesion samples submitted for bacteriological examination. Of the isolates, 25 were identified as Mycobacterium bovis, 3 as M. avium-intracellulare-scrofulaceum complex, one as M. fortuitum and one as M. flavescens. The M. bovis isolates from buffaloes showed minor cultural differences to those normally characteristic of bovine isolates.

Abattoirs↗
PubMed1981

An abattoir survey of diseases of feral goats.

Caseous lymphadenitis was the most frequently encountered pathological condition in 3,720 feral goats examined during routine meat inspection procedures. Among 9 separate consignments of animals, the prevalence of infection averaged 7.4% (range 0.3% to 18.8%). The majority of lesions were seen in lymph nodes draining superficial body areas although many also occurred in internal nodes and organs. Corynebacterium ovis was isolated from 25 of 32 lesions submitted for bacteriological examination. Other conditions regularly encountered included pneumonia, cysticercosis, sarcosporidiosis and lice infestation, while myonecrosis, pleurisy, pericarditis, nephritis, hepatitis, cirrhosis and mite infestation were only occasionally found. A total of 171 serum samples were collected and tested against 17 antigens. Samples from 57.9% and 51.5% of goats showed positive serological reactions to the antigens for sarcosporidiosis and Q fever respectively.

Abattoirs↗