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101.
This review describes the variation of glucose-6-phosphate dehydrogenase (G6PD) activity in the main neurons of the molecular and granular layers as well as in the deep nuclei of the cerebellum as observed so far by optical and electron microscopy studies. Light microscopy and semiquantitative microphotometry of histochemical staining showed that the highest G6PD activity was expressed by Purkinje cells and neurons of the deep cerebellar nuclei; the elements of the molecular layer showed a diffuse G6PD staining, while the granular layer displayed only scattered G6PD activity. Electron microscopy analysis showed that the basket and stellate cells, as well as the Golgi cells, have a remarkable G6PD activity, while in the granule cells the enzyme was barely detectable. The results show that cerebellar G6PD activity changes with different neuron types as a function of its role in sustaining NADPH dependent pathways in these cells. 相似文献
102.
Expansion of tumor-specific CD8+ T cell clones in patients with relapsed myeloma after donor lymphocyte infusion 总被引:2,自引:0,他引:2
Orsini E Bellucci R Alyea EP Schlossman R Canning C McLaughlin S Ghia P Anderson KC Ritz J 《Cancer research》2003,63(10):2561-2568
Donor lymphocyte infusions (DLI) provide effective therapy for patients with multiple myeloma who have relapsed after allogeneic bone marrow transplantation. However, the immunological mechanisms of the graft-versus-myeloma (GVM) effect have not been defined, and the target antigens of this response have not been identified. Molecular analysis of CDR3 Vbeta repertoire after CD4+ DLI demonstrated previously that the development of GVM and graft-versus-host-disease (GVHD) were associated with the clonal expansion of distinct T-cell populations in patient peripheral blood. In the current study, we undertook a molecular and functional characterization of GVM- and GVHD-associated T-cell clones. T-cell clones associated with GVM were detectable by clone-specific PCR at a low level in peripheral blood before DLI and expanded approximately 10-fold after DLI. In contrast, T-cell clones associated with GVHD were not detectable before DLI or before the development of clinical GVHD. Two T-cell clones associated with GVM were isolated and expanded in vitro, allowing their phenotypic and functional characterization. Both GVM clones were derived from donor cells and had a CD3+CD8+CD4- phenotype. One GVM clone specifically recognized patient myeloma cells in an HLA class I-restricted manner, but was not reactive with patient normal bone marrow cells or patient EBV transformed B cells. Taken together, these findings suggest that the GVM response is mediated by donor-derived CD8+ T-cell clones with antimyeloma specificity that may be present before DLI. In contrast, T-cell clones associated with GVHD are expanded de novo after DLI. 相似文献
103.
Morra E Cesana C Klersy C Varettoni M Cavanna L Canesi B Tresoldi E Barbarano L Lazzarino M;Hematology/Oncology Studies Trials 《Seminars in oncology》2003,30(2):172-177
The natural history of asymptomatic IgM monoclonal gammopathies (MG) and variables predicting evolution to symptomatic lymphoproliferative disorders were investigated in 452 patients diagnosed from 1975 to 2001. Univariate and multivariate Cox models were used to identify possible predictors of disease progression. At a median follow-up of 49 months (range, 12 to 233), 41 cases (9.1%) evolved to symptomatic Waldenstrom's macroglobulinemia (n = 36), non-Hodgkin's lymphoma (n = 2), B-cell chronic lymphocytic leukemia (n = 1), IgM multiple myeloma (n = 1), and primary amyloidosis (n = 1); the median interval from diagnosis was 53 months (range, 12 to 154). The cumulative probabilities of transformation into a symptomatic lymphoproliferative disease at 5 and 10 years were 8% (95% confidence interval [CI], 6% to 12%) and 21% (95% CI, 16% to 29%), respectively. At univariate analysis, monoclonal component size and hemoglobin level as continuous parameters, lymphocytosis (>4 x 10(9)/L), bone marrow lymphoplasmacytoid infiltration (>10%), erythrocyte sedimentation rate (>40 mm/h), and detectable Bence Jones proteinuria were significantly related with evolution probability. At multivariate analysis, paraprotein level (P <.0001), hemoglobin level (P <.05), and lymphocytosis (P <.0001) independently predicted malignant evolution (P <.0001). In conclusion, patients with asymptomatic IgM-MG showing hematological features predictive of progression should be carefully monitored in view of an early treatment of the disease. 相似文献
104.
Nieri P Martinotti E Testai L Martinelli C Breschi MC 《European journal of pharmacology》2003,475(1-3):115-118
The effects of cannabinoid receptor agonists on the non-adrenergic non-cholinergic (NANC) inhibitory responses to electrical field stimulation in guinea-pig trachea were assessed. R-(+)-[2,3-dihydro-5-methyl-3-[(morpholilinyl) methyl]pyrrolo [1,2,3-de]-1,4-benzoxazin-6-yl]-(1-naphthalenyl)methanone mesylate (WIN 55,212-2; 10(-5) M) significantly enhanced the frequency-dependent response to electrical stimulation. The same concentration of R-(N)-(2-hydroxy-1-methylethyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (R(+)methanandamide) and 1-propyl-2-methyl-3-(1-naphthoyl)indole (JWH-015) did not affect significantly the electrically induced inhibitory NANC responses. The effect of WIN 55,212-2 was not modified by the cannabinoid CB1 and CB2 receptor-selective antagonists, N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride (SR141716A; 10(-5) M) and N-(1S)-endo-1,3,3-trimethyl bicyclo [2.2.1] heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR 144528; 10(-5) M), respectively. Moreover, the nitric oxide synthase inhibitor, L-NG-nitro-arginine methyl ester (L-NAME; 10(-4) M), but not the peptidase, alpha-chymotrypsin (2 U/ml), blocked the effect of WIN 55,212-2. Postsynaptically, WIN 55,212-2 did not produce any change of tracheal smooth muscle tone, either basal or histamine-induced, and did not interfere with the relaxant activity of the nitric oxide donor, sodium nitroprusside (10(-8)-10(-4) M). In conclusion, our results suggest that (a) cannabinoid CB1 and CB2 receptor stimulation does not alter the inhibitory NANC transmission in guinea-pig trachea, and (b) WIN 55,212-2 potentiates the NO-mediated component of the NANC relaxant response to electrical stimulation through a cannabinoid receptor-independent mechanism. 相似文献
105.
Collina S Azzolina O Vercesi D Brusotti G Rossi D Barbieri A Lanza E Mennuni L Alcaro S Battaglia D Linati L Ghislandi V 《Il Farmaco; edizione pratica》2003,58(9):939-946
In the present paper, we report on the synthesis and antinociceptive activity of a new series of N-methyl-arylpyrrolidinols that we designed for a rational structure-activity relationship (SAR) study. The antinociceptive properties were investigated in vivo by the hot plate and formalin tests in mice and control on the locomotory activity was also monitored by the rota rod test. With this aim, the evaluation of the lipophilicity of all compounds was performed by the Daylight computational method in order to better understand the SAR. Interesting properties were proven for the compounds of the entire series. 相似文献
106.
Cecchetti V Calderone V Tabarrini O Sabatini S Filipponi E Testai L Spogli R Martinotti E Fravolini A 《Journal of medicinal chemistry》2003,46(17):3670-3679
A series of 1,4-benzothiazines, suitably functionalized at the N-4 and C-6 positions, arising from the replacement of a benzopyran-based structure of cromakalim with a 1,4-benzothiazine nucleus, has been synthesized as potassium channel openers (KCOs). Most of the tested compounds show high vasorelaxant potency that is considerably higher than that of the reference levcromakalim (LCRK). In the presence of the well-established selective K(ATP) blocker, glibenclamide, the vasorelaxing effects were antagonized in a competitive fashion, indicating the involvement of the K(ATP) channel in their pharmacological effect. Some aspects of the structure-activity relationship associated with the N-4 and C-6 substituents are discussed. The highest level of activity was achieved with a cyclopentenone ring at the N-4 position coupled with an electron-withdrawing group such as nitro, trifluoromethyl, or cyano at the C-6 position. Compounds 4c, 5c, and 6c displayed a vasorelaxant potency at least 10 000 times greater than that of LCRK, thus becoming the most potent KCOs identified to date. 相似文献
107.
The xanthones gentiacaulein and gentiakochianin are responsible for the vasodilator action of the roots of Gentiana kochiana 总被引:2,自引:0,他引:2
Chericoni S Testai L Calderone V Flamini G Nieri P Morelli I Martinotti E 《Planta medica》2003,69(8):770-772
Gentiana kochiana Perr. et Song. (Gentianaceae), a plant used in the traditional medicine of Tuscany (Italy) as antihypertensive remedy, exerts a vasodilator action on in vitro aortic rings that is probably linked to the blocking of the ryanodine-sensitive Ca++ channels. In the present study, three known xanthones were isolated from the crude methanolic extract of the roots: gentiacaulein, gentiakochianin, and swertiaperennin. The first two showed a vasorelaxing activity in rat aortic preparations, pre-contracted by 3 microM norepinephrine (pIC50 = 5.00 +/- 0.032 for gentiacaulein, pIC50 = 4.95 +/- 0.068 for gentiakochianin), 20 mM KCl (pIC50 = 4.90 +/- 0.15 for gentiacaulein; 4.59 +/- 0.069 for gentiakochianin), or 5 mM caffeine; on the contrary, in the same conditions, swertiaperennin did not show any vasodilator effect. In conclusion, gentiacaulein and gentiakochianin seem to be the compounds responsible for the vasorelaxing properties of the crude extract of Gentiana kochiana roots. 相似文献
108.
109.
Strong S Baptiste S Salvatori P 《Canadian journal of occupational therapy. Revue canadienne d'ergothérapie》2003,70(1):11-20
BACKGROUND: In response to the demand for therapists and changes in vocational practice, a needs assessment was conducted to update an occupational therapy educational program. METHOD: Employing focus groups, interviews and questionnaires, 66 therapists from a wide range of graduating institutions working in vocational practice were asked to: a) identify the essential knowledge, skills and professional behaviours required for vocational practice; b) determine to what extent training is preparing students for vocational practice; and c) make recommendations for curriculum revision and/or for additional curriculum development. Participants and their jobs were profiled together with the challenges and issues of vocational practice. RESULTS: There was strong agreement among participants regarding what is required to practice effectively but disparate views concerning the extent they were prepared for practice. CLINICAL IMPLICATIONS: Recommendations were given for entry and postgraduate level curricula. Findings were compared to a past community practice survey. Implications for practicums, professional integrity and ethical issues were discussed. 相似文献
110.
Claudio De Felice Licia Leoni Enrica Tommasini Gabriele Tonni Paolo Toti Antonio Del Vecchio Grazia Ladisa Giuseppe Latini 《Pediatric critical care medicine》2008,9(2):203-208
OBJECTIVE: Evidence suggests increased morbidity, in particular early neonatal respiratory complications, in newborns from elective cesarean section compared with those from vaginal delivery. No reliable maternal predictors of adverse neonatal outcome at elective cesarean section are known. Here, we prospectively tested the hypothesis that a low maternal perfusion index at the baseline phase (i.e., preanesthesia) of the elective cesarean section is a predictor of early adverse neonatal respiratory outcome. DESIGN: Prospective cohort study. SETTING: Operating and delivery rooms of a public health hospital with a tertiary-level neonatal intensive care unit. PATIENTS: Forty-four healthy pregnant women with no known risk factors undergoing elective cesarean section at term gestation. INTERVENTIONS: Elective cesarean section was divided into nine phases. Analysis of pulse oximetry-derived signals (perfusion index, pulse rate, and oximetry) and systolic, diastolic, and differential blood pressure were recorded. Maternal arterial and venous newborn cord blood gas analyses and placental histology were evaluated. MEASUREMENTS AND MAIN RESULTS: Early respiratory complications (transient tachypnea of the newborn, n = 5; respiratory distress syndrome, n = 1) were observed in 13.6% (6 of 44) of the newborns. A maternal perfusion index < or = 1.9 (lower quartile) during the preanesthesia phase of the elective cesarean section was an independent predictor of early adverse neonatal respiratory outcome (odds ratio 68.0, 95% confidence interval 6.02-767.72; p < .0001). CONCLUSIONS: A decreased perfusion index value in the preanesthesia phase of elective cesarean section is a maternal predictor of increased neonatal morbidity and is significantly related to subclinical placental inflammatory disease. These observations suggest the feasibility of a noninvasive pulse oximeter prenatal screening of the high-risk fetus/newborn in elective cesarean section. 相似文献