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81.
82.
This study examined the effects of culture conditions and hormone treatment on androgen production by mouse interstitial cells in short-term primary culture. Testicular interstitial cells (18-25% 3 beta-hydroxysteriod dehydrogenase-positive) were maintained in serum-free hormone supplemented medium. Basal (nonstimulated) androgen production was found to be plating-density dependent. Androgen production per cell increased dramatically in a time- and cell concentration-dependent manner. This effect was reproduced in low density cultures by addition of charcoal-stripped conditioned medium from high density cultures. The cell anchorage factors, fibronectin and poly-l-lysine, similarly enhanced basal androgen production but did not augment responsiveness to luteinizing hormone (LH). Coating of the culture surface with serum inhibited androgen production. Cultured cells remained responsive to LH for 4 to 5 days and both insulin (5 micrograms/ml) and epidermal growth factor (EGF) (3 ng/ml) augmented LH-stimulated androgen production. There was a transient increase in LH sensitivity and maximum LH-stimulated androgen production for 5 to 72 h in culture followed by a decline in androgen production to low levels after 4 to 5 days in culture. This loss of activity was partially prevented by addition of antioxidants to the medium or by reduction of the ambient O2 concentration to 1%. 相似文献
83.
Sullivan C. E.; Kozar L. F.; Murphy E.; Phillipson E. A. 《Journal of applied physiology》1978,45(1):11-17
84.
The Flora of the Perivaginal Area: The Normal Flora and the Effect of a Deodorant Spray 总被引:1,自引:1,他引:0
Susan Crowley Catherine T. Murphy Pamela M. White W. C. Noble Elizabeth R. M. Rowell D. Bluett 《Journal of applied microbiology》1974,37(3):385-392
S ummary . The microbial flora of the thigh adjacent to the vaginal labia and of the mucosal surface of the labia has been examined quantitatively and qualitatively in students from Colleges of Education and a University, and in persons attending a Consultant Gynaecologist for non-suppurative conditions. In the 2 student populations, members of the Micrococcaceae and diphtheroids were the most common organisms but all populations yielded many organisms of gut origin. Differences between the populations may relate to social and hygienic conditions and should make us wary of direct comparisons with other, different populations. The effect of intimate hygiene deodorants containing 0.01% or 0.02% of chlorhexidine was compared with a base spray containing no antibacterial agent. No significant effect of these sprays on the microbial flora could be demonstrated. 相似文献
85.
86.
Cyril Murphy 《BMJ (Clinical research ed.)》1944,1(4334):150-151
87.
88.
J W Murphy R L Mosley J W Moorhead 《Journal of immunology (Baltimore, Md. : 1950)》1983,130(6):2876-2881
Cryptococcosis patients frequently have high levels of cryptococcal antigen in their body fluids, and the levels of circulating antigen can generally be used to predict the patient's recovery, with high or rising antigen titers indicating a poor prognosis and low or decreasing levels a good prognosis. In a previous study, we reported on a murine model for studying the effects of cryptococcal antigen on host defense mechanisms. In that work, we demonstrated that an i.v. injection of cryptococcal antigen (CneF) into CBA/J mice, to simulate the antigenemia known to occur in human cryptococcosis, induced a population of T suppressor cells (Ts1) in the lymph nodes (LN). Upon adoptive transfer, the Ts1 cells specifically suppressed the afferent limb of the delayed-type hypersensitivity (DTH) response to cryptococcal antigen. In the present study, we show that the precursors of the Ts1 cells are sensitive to low-dose cyclophosphamide treatment and that the phenotype of the Ts1 cells is Lyt-1+, Ia+ (I-J+). LN cells from CneF-injected mice or a soluble factor derived therefrom can induce in the spleens of recipient mice a second-order suppressor cell population that suppresses the efferent limb of the DTH response. The cells that induce the second-order or efferent suppressor cells have the same phenotype as the cells that appear to suppress the afferent limb of the DTH response. The findings in this study indicate that a complex regulatory mechanism is responsible for the observed suppression of the DTH response in this infectious disease model. Furthermore, the suppressive circuit thus far defined for cryptococcal antigen is similar to the antigen-specific suppressor cell pathway outlined for certain chemically defined haptenic systems. 相似文献
89.
Weiduan Xu Jianmin Chen Glenn Yamasaki John E. Murphy Baisong Mei 《Molecular biotechnology》2010,45(3):248-256
Many therapeutic proteins require appropriate glycosylation for their biological activities and plasma half life. Coagulation
factor VIII (FVIII) is a glycoprotein which has extensive post-translational modification by N-linked glycosylation. The terminal
sialic acid in the N-linked glycans of FVIII is required for maximal circulatory half life. The extent of FVIII sialylation
can be determined by high pH anion-exchange chromatography coupled with a pulse electrochemical detector (HPAEC-PED), but
this requires a large amount of purified protein. Using FVIII as a model, the objective of the present study was to develop
assays that enable detection and prediction of sialylation deficiency at an early stage in the process and thus prevent downstream
product quality excursions. Lectin ECA (Erythrina Cristagalli) binds to unsialylated Galβ1-4 GlcNAc and the ECA-binding level (i.e., terminal Gal(β1-4) exposure) is inversely proportional
to the level of sialylation. By using ECA, a cell-based assay was developed to measure the global sialylation profile in FVIII
producing cells. To examine the Galβ1-4 exposure on the FVIII molecule in bioreactor tissue culture fluid (TCF), an ELISA-based
ECA-FVIII binding assay was developed. The ECA-binding specificity in both assays was assessed by ECA-specific sugar inhibitors
and neuraminidase digestion. The ECA-binding specificity was also independently confirmed by a ST3GAL4 siRNA knockdown experiment.
To establish the correlation between Galβ1-4 exposure and the HPAEC-PED determined FVIII sialylation value, the FVIII containing
bioreactor TCF and the purified FVIII samples were tested with ECA ELISA binding assay. The results indicated an inverse correlation
between ECA binding and the corresponding HPAEC-PED sialylation value. The ECA-binding assays are cost effective and can be
rapidly performed, thereby making them effective for in-process monitoring of protein sialylation. 相似文献
90.
Although pharmacological stimulation of a wide variety of transmitter receptors triggers phosphoinositide (PI) turnover, little is known about the type of synaptic activity required to activate this system. To investigate this question, we have used primary cultures of embryonic cortical neurons, which develop functional glutamate and GABA synapses during maturation in vitro. Mature cultures display spontaneous synaptic activity that is totally suppressed by tetrodotoxin (TTX). PI turnover, assayed by the lithium-sensitive accumulation of [3H]CDP-diacylglycerol, was readily detected under basal conditions and was abolished by TTX. Increased excitatory synaptic activity induced by picrotoxin, an antagonist of GABAA receptor-mediated inhibition, further stimulated PI turnover. Similar results were obtained when PI turnover was assayed using [3H]inositol labeling. With either assay, the magnitude of synaptically induced PI turnover was comparable to maximal responses produced by muscarinic receptor stimulation. Although a component of the spontaneous synaptic currents is sensitive to N-methyl-D-aspartate (NMDA)-preferring glutamate receptor antagonists, blockade of NMDA receptors did not affect PI turnover associated with synaptic transmission. To assess the time course of synaptically mediated PI turnover, the amplitude and duration of spontaneous synaptic currents were reduced by lowering the extracellular Ca2+ concentration from 2.25 to 0.5 mM, a maneuver that suppresses basal PI turnover. Increases in PI turnover were detected as early as 5 min following restoration of the extracellular Ca2+ concentration to 2.25 mM. Taken together, these findings indicate that activation of the PI system is associated with physiological levels of glutamatergic synaptic transmission. 相似文献