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91.
The aim of the present study was to examine the cellular basis of the involvement of oestradiol and progesterone in blastocyst implantation in the primate. To this end, the cellular distribution of receptors for oestradiol (ER) and progesterone (PR) in fetal trophoblast cells and in endometrial compartments of timed lacunar (pre-villous) and villous stages of placentation in primary implantation sites collected on days 13-22 of gestation were investigated in rhesus monkeys. Both in pre-villous stage tissue and in villous stage tissue, cytotrophoblast cells and syncytiotrophoblast cells and other trophoblast derived cells were PR positive, while they were generally ER negative. Maternal endometrial cells were ER negative, while epithelial cells, stromal cells and vascular endothelial cells in maternal endometrium showed heterogeneous staining patterns for PR depending on their relative location; these patterns, however, correlated well with glandular hyperplasia and differentiation, stromal-decidual transformation and vascular response seen during blastocyst implantation. 相似文献
92.
Immunohistological localisation of vascular endothelial growth factor in human endometrium. 总被引:2,自引:0,他引:2
B Naresh J Sengupta V Bhargava G Kinra J Hu D Ghosh 《Indian journal of physiology and pharmacology》1999,43(2):165-170
Several polypeptide growth factors regulate epithelial and stromal development in endometrium under the influence of estrogen and progesterone, and thereby regulate growth and differentiation of endometrium during menstrual cycle. However, little is known about the angiogenic growth factors that may affect endometrial vasculature throughout each menstrual cycle. Vascular endothelial growth factor (VEGF) is suggestively an important angiogenic growth factor in the female reproductive tract. The aim of the present study was to immunolocalize and assess semi-quantitatively VEGF immunostaining in cells of proliferative phase (n = 3), secretory phase (n = 6) and hyperplastic (n = 6) human endometrial samples. VEGF concentrations were significantly higher in glandular (P < 0.001) and stromal (P < 0.01) compartments of proliferative stage endometrium compared with those in secretory stage and hyperplastic endometrial samples, with no difference in the scores for glandular and stromal compartments between secretory stage and hyperplastic endometrial samples. Generally, glandular expression of VEGF was higher as compared to stromal compartment. Thus, it appears that endometrial VEGF expression and concentration are enhanced by estrogen, and may be correlated with neovascularization and increased vascular permeability during late proliferative period. Additionally, there was no enhancement in VEGF expression in hyperplastic glands, suggesting that regulation of glandular growth and that of angiogenesis in human endometrium operate through different mechanisms. 相似文献
93.
The antagonist activity of the metabotropic glutamate receptor ligand (2S,1'S,2'S)-2-methyl-2(carboxycyclopropyl)glycine (MCCG) was examined using the [35S]GTPgammaS binding and forskolin (FSK)-stimulated adenosine 3':5'-cyclic monophosphate (cAMP) assays with recombinant Chinese hamster ovary (CHO) cells expressing the G protein-coupled human subtype 2 metabotropic glutamate (hmGlu2) receptor. Whereas MCCG proved to be a partial agonist in the GTPgammaS binding assay, it not only antagonized the agonist effect of (IS,3R)-ACPD in the cAMP assay but further produced an anomalous increase of the cAMP level relative to baseline. The anomalous MCCG response was also observed following treatment of the cells with MCCG in the absence of added agonist. Determination of the glutamate concentration in the incubate at the start and end of the cAMP reaction revealed the existence of micromolar concentrations of cellularly released glutamate throughout the course of the assay, reaching levels which exceeded its reported affinity for the mGlu2 receptor. Considering MCCG's partial agonist effect in the GTPgammaS binding assay and its pseudo-inverse agonist effect in the cAMP assay, available methods of estimating its antagonist potency were inappropriate since the classical Schild method and the alternative model suggested by Waud both assume the antagonist to lack a concentration-response relationship. We derived an alternate design and models that permit estimation of the pA2 (pAx), Kd and IC50 for antagonists which produce a concentration related effect when applied by themselves. With their use, the data acquired in both assays support the designation of MCCG as a competitive antagonist of the hmGlu2 receptor and provide similar pA2 estimates between assays. In addition, the newly derived models and design permit the determination of antagonist potency for partial and inverse agonists so characterized in studies employing the Schild design. 相似文献
94.
95.
SK VERMA 《Medical Journal Armed Forces India》1996,52(2):113-115
The effect of vagotomy on the post-prandial alkaline tide was assessed by measuring the fasting and postprandial urinary pH before and after vagotomy in 50 cases of chronic duodenal ulcer treated by posterior truncal vagotomy or gastrojejunostomy or pyloroplasty. Results showed that post-prandial urinary pH fell after vagotomy confirming the completeness of vagotomy. This test is safe, reliable, noninvasive and a simpler bedside procedure as compared to the conventional Hollander''s insulin test.KEY WORDS: Vagotomy, Alkaline tide 相似文献
96.
P Ghosh 《The Journal of laryngology and otology》1977,91(12):1077-1083
A new one-stage operation of constructing a 'Neo-Larynx' after total laryngectomy, transverse tracheo-oesophagoplasty, for a good alaryngeal ('Tracheo-Oesophageal') speech is described. A 'Neo-Epiglottis' is constructed from the posterior tracheal wall and a 'Pseudo-Glottis' in the tracheo-oesophagenal partition wall with a valvular mechanism for preventing aspiration into the trachea during deglutition. No extraneous tissue is used for the construction of the 'Neo-Larynx' and no practice is necessary on the part of the patient for developing alaryngeal 'Tracheo-Oesophageal' speech. The patient can phonate immediately after removal of the feeding tube and the silastic sheet and is ready for discharge five weeks after operation. Adequate surgical ablation is ensured and at the same time good functional rehabilitation is offered without jeopardizing the principles of cancer surgery, i.e. to be on the overdoing side rather than on the underdoing one in a futile attempt at retaining the function. 相似文献
97.
The synthesis and release of procoagulant activity (PCA) from leukaemic leucocytes was studied in anin vitro culture system stimulated by endotoxin. Puromycin, actinomycin-D, vinblastine, colchicine, dibutyryl cyclic AMP and ouabaln were added to the culture system to study some of the metabolic processes of these cells in relation to synthesis and release of PCA. It was found that production of PCA is an active process and depends on new protein synthesis. The release of PCA from cells can be inhibited by vinblastine, an inhibitor of microfilament and microtubules in the cell. The optimal release of PCA occurs at pH 7.2-@#@ 7.4 at 37°C and is not inhibited by the ATPase inhibitor ouabaln. Dibutyryl cyclic AMP inhibits the release/synthesis of PCA. Gram negative septicaemia and endotoxinaemia are capable of increased production and release of PCA from leukaemic cells and could contribute to the coagulation fallure seen in this disease. 相似文献
98.
P K Ghosh G Pohla-Gubo H Pohla H Antretter F Unger 《The Journal of cardiovascular surgery》1992,33(1):28-32
Serial estimation of total immunoglobulin E (IgE) concentration in 30 consecutive male patients undergoing coronary artery bypass grafting revealed three patterns--a low, middle and high response--during the perioperative period. The mean IgE level was higher in patients with higher mean preoperative left ventricular ejection fractions and these patients had a higher left ventricular stroke work index. However, there was no correlation with the severity of coronary artery disease or with degree of adequacy of revascularisation. Mean IgE level correlated moderately well with the mean right ventricular stroke work index and mean pulmonary capillary wedge pressure and minimally with the triple index. A higher level of IgE was usually observed with better cardiac performance and may be associated with factors related to the pulmonary circulation. However we could neither confirm nor refute whether an elevated level of IgE indicated an increased risk of cardiovascular events or a "protected status" against the complications of necrotising ischemia. 相似文献
99.
A. C. Sharma S. K. Kacker P. Ghosh 《Indian journal of otolaryngology and head and neck surgery》1977,29(3):107-113
Nystagmus is said to be the most important expression of vestibular disease. It can be observed with the naked eye but behind a Frenzel’s glass it can be observed better. For accurate reading, electrical recording is necessary and for that purpose the change in the corneo-retinal potential consequent upon the movement of the eye has been utilised. This technique of recording is called Electronystagmography (E.N.G.). With the electronystagmograph one can determine the amplitude, frequency and velocity of the slow component. It also helps in recording nystagmus behind the closed eyes or with the eyes open in darkness and in light. It is universally agreed that the maximum information that can be gained is by calculating the maximum velocity of the slow component (Henriksson 1955, Van Egmond and Torok (1954), Aschan et al 1956 and Sokolovski, 1966.). 相似文献
100.
Girija P Dasmahapatra Parijat Didolkar Michael C Alley Somiranjan Ghosh Edward A Sausville Krishnendu K Roy 《Clinical cancer research》2004,10(15):5242-5252
PURPOSE: Antineoplastic agents often achieve antitumor activity at the expense of close to unacceptable toxicity. One potential avenue to improve therapeutic index might combine agents targeting distinct components of the same growth regulatory pathway. This might lead to more complete modulation of the target pathway at concentrations lower than those associated with limiting adventitious toxicities from either agent alone. The protein kinase antagonist UCN-01 is currently used in Phase I/II trials and has recently been demonstrated to inhibit potently PDK1. We have recently documented that the alkylphospholipid perifosine potently also inhibits Akt kinase (PKB) activation by interfering with membrane localization of Akt. This leads to the hypothesis that these two agents might act synergistically through distinct mechanisms in the PI3K/Akt proliferation and survival-related signaling pathway. EXPERIMENTAL DESIGN: The synergistic effects of UCN-01 and perifosine, on two cell lines (A-549 and PC-3), were examined using various long-term in vitro assays for cell growth, cell cycle distribution, clonogenicity, survival morphology, and apoptosis. Along with Western blotting experiments were performed to determine whether this synergistic combination of two drugs has significant effect on their downstream targets and on biochemical markers of apoptosis. RESULTS: After 72 h, perifosine at concentrations of 1.5 and 10 microM UCN-01 at 40 and 250 nM did not significantly affect the growth of PC-3 and A459 cells, respectively. However, in combination at the same respective individual concentrations (1.5 microM and 40 nM of perifosine and UCN-01, respectively, in PC-3 cells and 10 microM perifosine and 0.25 microM UCN-01 in the somewhat more resistant A549 cells), virtually complete growth inhibition of both the cell lines resulted. Supra-additive inhibition of growth was also demonstrated in independent clonogenic assays. Mechanistic studies in cell culture models suggest enhanced depletion of the S-phase population in cells treated by the combination. This correlated with enhanced inactivation of Akt along with activation of caspases 3 and 9 and poly(ADP-ribose) polymerase cleavage. Evidence of synergy was formally demonstrated and occurred across a wide range of drug concentrations and was largely independent of the order or sequence of drug addition. CONCLUSIONS: As the concentrations of UCN-01 and perifosine causing synergistic inhibition of cell growth are clinically achievable without prominent toxicity, these data support the development of clinical studies with this combination. 相似文献