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101.
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
102.
103.
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
104.
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
105.
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
106.
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
107.
Radical Resection of Periampullary Tumors in the Elderly: Evaluation of Long-term Results 总被引:5,自引:0,他引:5
Bathe OF Levi D Caldera H Franceschi D Raez L Patel A Raub WA Benedetto P Reddy R Hutson D Sleeman D Livingstone AS Levi JU 《World journal of surgery》2000,24(3):353-358
Increasingly, patients of advanced age are coming for evaluation of periampullary tumors. Although several studies have demonstrated
the safety of resecting periampullary tumors in older patients, few long-term survival data have been reported. Between 1983
and 1992 various periampullary masses were resected in 70 patients over age 65 (range 65–87 years). Total pancreatectomy was
performed in 11 patients, and 59 patients underwent pancreaticoduodenectomy. The mean duration of hospitalization was 17 ±
15 days. Major complications occurred in 27 patients (39%), and operative mortality rate was 8.5%. Overall median survival
was 24 months; and 5-year survival was 25%. Perioperative outcome was compared in patients aged 65 to 74 years and in patients
≥75 years old. The older age group required longer periods in the surgical intensive care unit postoperatively, but the long-term
survival was similar in the two age groups. Radical resection with the intent to cure periampullary tumors is safe in selected
patients of advanced age, and long-term survival is in the range of expected survival for younger patients with the same tumors. 相似文献
108.
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
109.
P H Wiernik E Paietta O Goloubeva S J Lee D Makower J M Bennett J L Wade C Ghosh L S Kaminer J Pizzolo M S Tallman 《Leukemia》2004,18(10):1605-1610
The Eastern Cooperative Oncology Group (ECOG) performed a phase 2 study in B-cell chronic lymphocytic leukemia (CLL) of oral theophylline, a methylxanthine that inhibits cyclic nucleotide phosphodiesterases, thereby inducing the intracellular accumulation of cyclic adenosine monophosphate (cAMP). In 25 patients with Rai stages 0-I, theophylline, 200 mg given orally every 12 h was well tolerated. There was one complete response after 22.5 months of treatment, which continues at 27+ months, and 18 other patients had stable disease. In vitro exposure of patients' lymphocytes to aminophylline (75-250 microg/ml), the soluble form of theophylline, resulted in dose- and time-dependent induction of apoptosis in 9/20 patients studied. Apoptosis was documented flow-cytometrically by monitoring the expression of bcl-2 and bax, forward light scatter, fluorescence intensity of binding of CD45 antibody, and the binding of annexin. Patients whose leukemic lymphocytes were susceptible to apoptosis induction by aminophylline in vitro experienced a significantly longer progression-free survival than patients whose cells were resistant to the drug in culture (P=0.025). This suggests that in a CLL population treated with theophylline, induction of an apoptotic response to the drug in vitro is prognostic for absence of clinical progression. 相似文献
110.
Manisha Garella MS DNB B. Ghosh MD MNAMS Meenakshi Thakar MD Sonu Nigarn MD Rajeev Jain MBBS 《Annals of Ophthalmology》2004,36(1):59-62
A case of a child with bilateral fleshy limbal masses with a coloboma of the right upper lid is discussed. Systemic examination
revealed two patches of alopecia on the right frontoparietal and right occipital areas of the scalp. Punch biopsy and histopathological
examination led to the diagnosis of Linear Nevus Sebaceus Syndrome (LNSS) with bilateral complex limbal choristomas.
The authors have stated that they do not have a significant financial interest or other relatioship with any product manufacturer
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes
unlabeled, unapproved, or investigative products or devices. 相似文献