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51.
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.  相似文献   
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PROBLEM: Human GRO-alpha (GRO-α) is a new member of the chemokine family that is supposed to play an important role in inflammatory and immune reactions. We established a sandwich enzyme-linked immunoassay (ELISA) system with polyclonal antibodies against human GRO-α and investigated the serum level of healthy donors to establish normal ranges for this chemokine in adults. METHODS: GRO-α concentrations were measured cross-sectionally in the sera of 240 healthy adults. The variability of serum GRO-α levels was also measured in normal volunteers, samples from whom were obtained by sequential venipunctures or by a small plastic cannula with a heparin-saline lock, to determine short-term variability. RESULTS: Whereas there was no difference between the concentration of human GRO-α from men (logarithmic mean, 77.6 pg/ml, n = 120) and that from women with normal menstrual cycles (log mean, 71.6 pg/ml, n = 73), the concentration from postmenopausal women (log mean 45.0 pg/ml, n = 31) was lower than that from women with normal menstrual cycles (log mean 71.6 pg/ml, n = 73). However, we could not detect any significant difference between healthy donors' serum levels and those of donors with acute inflammation. Fewer variations were recognized in the case of the sequential venipunctures method than in that of the heparin-saline lock method. CONCLUSION: We found that the GRO-α concentration of postmenopausal women was significantly lower than that of women with normal menstrual cycles. These results suggest the GRO-α serum levels of normal healthy women may have some correlation with sex hormones.  相似文献   
54.
Strains of Vibrio cholerae serogroup O1 biotype El Tor that are susceptible to Mukerjee cholera bacteriophage group IV (S. Mukerjee, Bull. W.H.O. 28:333-336, 1963) were found. Cholera vibrios isolated from epidemics in northeast Thailand were characterized, and 57 of 60 strains isolated in 1986 were susceptible to cholera phage IV. However, all 113 strains isolated in 1988 were not susceptible to the phage. All isolates in both epidemics revealed behaviors typical of El Tor vibrios, except phage IV susceptibility in the 57 strains. Although the plaques of phage IV were generally translucent, plaques on some isolates looked transparent, just like those on classical vibrios. The organisms grown in the plaques were lysogenized. If this kind of strain is frequently isolated, the biotype of V. cholerae O1 should be reconsidered.  相似文献   
55.
A simple and rapid method for the determination of macrophage activating factor is described. A new type of apparatus suitable for the measurement of macrophage chemiluminescence was devised, and the effect of lymphokines on macrophage activities was studied by measuring phorbol myristate acetate-induced luminol-dependent chemiluminescence. An outstanding feature of the new apparatus is that the plastic dish used for the cell culture can be used as the vessel for the chemiluminescence reaction. When thioglycollate-elicited ICR mouse peritoneal macrophages were incubated with lymphokines, their ability to generate chemiluminescence increased rapidly, reaching a maximal level at about 4 h, and then it progressively decreased to the control level at 8 h. Although this increasing effect of lymphokines on macrophage chemiluminescence was short-lived, it could be seen at a relatively low concentration, at which lymphokine-mediated cytotoxic activity of macrophages was not observed.  相似文献   
56.
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen.  相似文献   
57.
We have established a set of transgenic mouse lines in which the HLA-DRA gene was expressed in different cell types. In one line (DRα-24), DRαEβb molecules were expressed on thymic medullary and cortical epithelial cells and all lineages of bone marrow-derived antigen-presenting cells (APC) except for thymic macrophages. By contrast, expression of the molecules in another line (DRα-30) was found on thymic medullary and cortical epithelial cells but not on bone marrow-derived APC in the thymus and periphery. To evaluate the role of thymic epithelial cells in acquisition of T cell tolerance, comparative analysis of DRα-24 and DRα-30 was performed. In DRα-30, T cells expressing TcR Vβ5 and Vβ11 were eliminated to comparable levels to those in DRα-24, suggesting that expression of the DRαEβb molecules on thymic epithelial cells are sufficient for clonal deletion of the self-superantigen-reactive T cells. In addition, CD4+ T cells from DRa-30 as well as those from DRα-24 were tolerant to DRα-derived peptide/I-Ab complex expressed on spleen cells from DRα-24 even in the presence of exogenous interleukin-2. These observations suggest that expression of the DRα chain in thymic epithelial cells could induce T cell tolerance directed toward naturally processed DRα-derived peptide bound to I-Ab molecules, probably via clonal deletion of the self-reactive T cells.  相似文献   
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A new type of chemiluminescence (CL) was observed in thioglycolate-elicited ICR mouse peritoneal macrophages which had been incubated for 24 h in medium containing lymphokines (LK) and lipopolysaccharides (LPS), and then exposed to a CL reagent solution containing luminol and phorbol myristate acetate (PMA). The new CL, which was clearly distinguishable from PMA-induced CL, appeared immediately after the addition of the CL reagent solution, reaching a maximal level at about 30 s, and disappeared rapidly. We have called the new CL 'spontaneous CL', since it appeared spontaneously without PMA triggering. When the macrophages were incubated with LK in the presence of 10 ng/ml of LPS, the spontaneous CL began to appear after about 4 h incubation, the maximal level being reached at about 12 h, after which it decreased gradually on further incubation. After 48 h, it could not be observed at all. The spontaneous CL could be observed only in macrophages simultaneously treated with LK and LPS, as in the case of cytotoxicity. The correlation between spontaneous CL and cytotoxicity was suggested by the following; they showed a similar dose dependency to LK, and neither of them could be induced in aged macrophages which had been incubated in vitro for 1 day before exposure to LK and LPS. These results suggest that spontaneous CL measurement could possibly replace the cytotoxicity test as a simple method for the determination of macrophage activating factor.  相似文献   
60.
Although the prostate gland is a rich source of α1-adreno- (α1-AR) and m1-cholino receptors (m1-AChR), the membrane processes associated with their activation in glandular epithelial cells is poorly understood. We used the whole-cell patch-clamp technique to show that the agonists of the respective receptors, phenylephrine (PHE) and carbachol (CCh), activate cationic membrane currents in lymph node carcinoma of the prostate (LNCaP) human prostate cancer epithelial cells, which are not dependent on the filling status of intracellular IP3-sensitive Ca2+ stores, but directly gated by diacylglycerol (DAG), as evidenced by the ability of its membrane permeable analogue, OAG, to mimic the effects of the agonists. The underlying cationic channels are characterized by the weak field-strength Eisenman IV permeability sequence for monovalent cations ( P K(25) > P Cs(4.6) > P Li(1.4) > P Na(1.0)), and the following permeability sequence for divalent cations: P Ca(1.0) > P Mg(0.74) > P Ba(0.6) > P Sr(0.36) > P Mn(0.3). They are 4.3 times more permeable to Ca2+ than Na+ and more sensitive to the inhibitor 2-APB than SK&F 96365. RT-PCR analysis shows that DAG-gated members of the transient receptor potential (TRP) channel family, including TRPC1 and TRPC3, are present in LNCaP cells. We conclude that, in prostate cancer epithelial cells, α1-ARs and m1-AChRs are functionally coupled to Ca2+-permeable DAG-gated cationic channels, for which TRPC1 and TRPC3 are the most likely candidates.  相似文献   
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