Ovarian response to active immunization against luteinizing hormone in the cow

Two experiments were conducted to determine whether active immunization against luteinizing hormone (LH) could lead to ovarian cyst development in the cow. In Experiment 1, cyclic beef heifers were randomly assigned to receive bovine LH (bLH) conjugated with ovalbumin (LH-immunized; n=4) or ovalbumin alone (control; n=5). Blood samples were collected at monthly intervals from the LH-immunized heifers to determine antibody titers. Heifers were observed for estrous behavior twice daily. All heifers were slaughtered 4 mo after initial immunization and ovaries examined for follicular status. In Experiment 2, mature dairy cows were immunized with bLH (LH-immunized; n=4) or ovalbumin alone (control; n=3). Weekly blood samples were collected from all cows for 26 wk and ovaries were rectally palpated. Sera from all of the LH-immunized heifers and cows had antibodies to LH. All of the LH-immunized animals stopped cycling 1 mo after immunization. In spite of the fact that serum follicle stimulating hormone levels were unaffected, ovarian cysts could not be found in either the LH-immunized heifers or cows.     

Respiratory depression produced by centrally administered taurine in the cat

The effects of taurine (0.8-64.8 mumol) were studied on respiratory activity following intracisternal (cisterna magna) and intracerebroventricular (lateral ventricle) injections in cats anesthetized with alpha-chloralose. Respiratory activity was measured by using a Fleisch pneumotachograph and monitoring tracheal airflow. The flow signal was integrated to obtain tidal volume (VT) and respiratory rate (f) was obtained by counting the number of VT excursions over one minute. Inspiratory (TI), expiratory (TE) and total (TTOT) cycle durations were also determined during this time period. In addition, end-tidal CO2 was continuously monitored. Associated changes in arterial pressure (femoral artery cannula) and heart rate were also determined. After injections into the cisterna magna, taurine caused dose-related decreases in minute ventilation (VE). The maximal decrease in VE was from 495 +/- 59 to 64 +/- 14 ml/min (p less than 0.05), and was due to both decreases in VT (from 27 +/- 3 to 5 +/- 1 ml; p less than 0.05) and f (from 18 +/- 1 to 12 +/- 2 breaths/min; p less than 0.05). TE and TTOT were increased from 2.4 +/- 0.4 to 4.5 +/- 0.6 sec (p less than 0.05) and from 3.7 +/- 0.4 to 6.4 +/- 0.8 sec (p less than 0.05), respectively. Mean inspiratory flow (VT/TI), a measure of inspiratory drive, was decreased from 21 +/- 4 to 4 +/- 2 ml/sec (p less than 0.05). Apnea occurred in 5 of 6 animals after the 64.8 mumol dose. This respiratory depression occurred without any significant change in arterial pressure. After lateral ventricle injections, taurine also caused dose-related, but not as pronounced, decreases in respiratory activity. In addition, taurine caused significant decreases (p less than 0.05) in arterial pressure in doses that decreased VE. Taurine administered intravenously had no significant cardiorespiratory depressant effects. These data indicate that centrally administered taurine produces respiratory depression and, depending on the route of CNS administration, also produces hypotension.     

A comparison of the agar cloning and microtitration techniques for assaying cell survival and mutation frequency in L5178Y mouse lymphoma cells

Microtitration methods for assaying cell survival and mutation frequency to ouabain resistance, 6-thioguanine resistance and 1-β-d-arabinofuranosyl cytosine resistance in L5178Y mouse lymphoma cells were compared to the standard agar cloning technique. The two methods gave essentially similar results for untreated cells, and after treatment with ethyl methanesulphonate and 4-nitroquinoline 1-oxide. Potential advantages of the microtitration method as a routine assay system are discussed.     

Effect of temperature on drought resistance and growth of cotton plants

In cotton plants ( Gossypium hirsutum L. cv. B.J.A.) the temperature of the roots affected both root and shoot growth, as did the temperature of the shoot. Drought resistance increased when the temperature imposed on roots (27°C) was lower than that imposed on shoots (17°C); the result was a decrease in both transpiration and flow of root sap. Stomatal characteristics as measured by density, index and resistance, depended only on shoot temperature. Differences in drought resistance, depended only on shoot temperature. Differences in drought resistance seem to be a result of changes in transpiration flow modulated by the amount of absorbed water.     

Inhibition of the graft-versus-host response by BCGcw-induced suppressor cells or prostaglandin E1

Immunization of C57BL/6 mice with BCGcw stimulated a population of "suppressor cells" which had a decreased capacity to induce the graft-versus-host response. The graft-versus-host response was quantitated using the Simonsen splenomegaly assay. F1 mice (C57BL/6 X CBA) were inoculated intraperitoneally with 1 X 10(8) parental (C57BL/6) or (CBA) spleen cells. The F1 mice were sacrificed 13 days later and the resulting splenomegaly was 3-4 times the normal amount. F1 mice which were injected with parental BCGcw-primed C57BL/6 spleen cells had a 50% inhibition of splenomegaly, whereas BCGcw-primed CBA spleen cells (a strain which does not develop suppressor cells) did not show this inhibition. In vitro results also confirmed that only C57BL/6 mice and not CBA mice developed suppressor cells after BCGcw immunization. A second study showed that X-irradiated (1000 R) BCGcw-primed "suppressor cells" could inhibit splenomegaly caused by the inoculation of normal parental C57BL/6 cells into F1 mice. The mechanism by which BCGcw-primed "suppressor cells" caused this inhibition of splenomegaly was delineated and found to be dependent upon the secretion of prostaglandin (PGE-1). Indomethacin and aspirin, potent inhibitors of prostaglandin synthesis, blocked the activity of C57BL/6 BCGcw "suppressor cells" and splenomegaly resulted. Systemic administration of the prostaglandin (15S)-15-methyl PGE-1 reduced splenomegaly approximately 50% in F1 mice which were injected with C57BL/6 or CBA cells. These results indicated that immunization with BCGcw stimulated a population of "suppressor cells" which could cause a decrease in graft-versus-host response and that the secretion of prostaglandin was responsible for this inhibition.     

Cerebrospinal fluid-contacting neurons of the central canal and terminal ventricle in various vertebrates

Cell and Tissue Research - Cerebrospinal fluid (CSF)-contacting neurons were studied by means of electron microscopy in the spinal cord and/or terminal ventricle of the ray, Raja clavata...     

Immunologic and clinical improvement of progressive coccidioidomycosis following administration of transfer factor

Three patients with progressive coccidioidomycosis were given preparations of transfer factor (TF). Adverse reactions to TF were minimal. Following TF administration two of these patients had prolonged clinical remissions in their coccidioidal disease. Cellular immune responses were sequentially evaluated by coccidioidininduced delayed-type skin tests, lymphocyte blast transformation and macrophage inhibition factor production (MIF). These three patients each exhibited different cellular immune patterns before and after TF administration. Two patients converted their coccidioidin skin tests, and one converted lymphocyte transformation response to coccidioidin. Also, TF apparently favorably affected the MIF response in all three patients.