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141.
The generation of a productive primary immune response is dependent on the ability of na?ve T lymphocytes to recirculate through peripheral lymph organs to encounter specific antigen. The process of na?ve CD4(+) T cell entry into lymph nodes correlates with cell surface expression of L-selectin (CD62L), which mediates early tethering and rolling events to endothelium prior to entry. Here, we demonstrate that surface expression of CD62L enhances CD4(+) T cell activation in vitro. The synthetic hydroxamate metalloproteinase inhibitor (BB-3103), specifically inhibits activation-induced shedding of CD62L from CD4(+) T cells by TCR cross-linking and lowers proliferation in part by reducing rapid tyrosine phosphorylation of zeta-associated protein 70 kDa (ZAP-70) and by increasing cytosolic free Ca(2+) concentration mobilization. BB-3103 also inhibited the proliferative response of both murine CD4(+) Th1 and Th2 subsets in vitro but the inhibitory effects were sustained only in Th2-type cells. Similarly, BB-3103 mediated prolonged inhibition of allergen-dependent peripheral T cell proliferation in atopic dermatitis patients but not in healthy controls. Analysis of CD62L expression on murine CD4(+) T cell subsets revealed that surface expression was maintained on Th1 cells but not Th2 cells. The differential effects of BB-3103 on primed effector CD4(+) T cells may provide new insights into generating therapeutic agents capable of redressing the Th2/Th1 imbalance in allergic diseases.  相似文献   
142.
A study was performed to assess the prevalence of specific antibodies to human T cell lymphotropic retrovirus (HTLV-III) in patients with lymphadenopathy syndrome, patients with the acquired immune deficiency syndrome (AIDS), and those at risk of AIDS. Serum samples were obtained from these groups and from healthy controls in selected cities in Italy, and antibodies to HTLV-III were measured by immunofluorescence assay and, in a few patients, by Western blotting. In addition, IgM antibody values were measured in 82 of those positive for HTLV-III. Altogether, 235 out of 320 patients with lymphadenopathy syndrome had antibodies to HTLV-III, the proportions being highest in haemophiliacs, homosexuals, and drug addicts from Rome; 11 out of 12 patients with AIDS had antibodies; 78 out of 439 subjects at risk for AIDS had antibodies; and six out of 30 patients with lymphadenopathy syndrome and positive for HTLV-III antibodies and nine of 52 patients at risk of AIDS had a detectable titre of IgM. HTLV-III is widespread in groups at risk of AIDS in Italy, and antibodies to HTLV-III are highly prevalent in patients with lymphadenopathy syndrome. A higher proportion of drug abusers were positive for antibodies than in previous studies. HTLV-III "infection" would appear to be spread mainly in compromised hosts, as none of the controls were positive for antibodies.  相似文献   
143.
144.
The case of a four-year-old boy is reported in whom the diagnosis of multiple cerebral and cerebellar focal tuberculous infections ("tuberculomas") was made. The diagnosis was based on a positive skin test, a history of contact, typical x-ray findings in the lung, CSF findings, and CT scan. The patient was treated during a three-year-period with antituberculous therapy. Sequential CT scans showed a relatively slow modification of the lesions, during a period of at least eighteen months, and thereafter their almost complete regression.  相似文献   
145.
The cirrhotic condition is characterized by a series of changes in physiological functions and of subclinical alterations that imply an abnormal and fragile adaptive pattern with reduced resistance to superimposed distress. In the care of the critically ill cirrhotic patient, the supportive measures aimed at maintaining physiological stability through the control of such debilitating factors have a key role and are not secondary in importance to the more obvious measures needed to treat clinically evident and specific alterations or complications. The relationship between hepatic malfunction and the development of these physiological abnormalities is not fully understood. Our knowledge of the problem, however, has been recently improved and the need for supportive measures motivated by a series of notions on cardiorespiratory and metabolic abnormalities and interactions in hepatic decompensation.
Resumen La condición cirrótica se caracteriza por una serie de cambios en las funciones fisiológicas y por alteraciones subclinicas que implican un patrón de adaptación anormal y fragil de resistencia reducida al estrés. Estas incluyen disfunción respiratoria con tendencia a la hipoxemia arterial en presencia de elevados indices cardiacos, una situatión crónica de hiperdinamismo cardiovascular pero con precaria eficacia miocárdica y latente riesgo de falla de alto débito, y cambios metabólicos que se traducen en un estado de fallas multisistémicas interrelacionadas características del cirrótico. En el cuidado del paciente cirrótico en estado crítico, las medidas de soporte orientadas al mantenimiento de la estabilidad fisiológica mediante el control de tales factores debilitantes tienen una importancia capital y no son secundarias frente a aquellas muy obvias que se requieren para tratar alteraciones o complicaciones específicas y clínicamente evidentes. La relación entre la disfunción hepática y el desarrollo de las mencionadas anormalidades fisiológicas no está totalmente aclarada, sin embargo, el estado de nuestro conocimiento sobre el problema ha sido enriquecido recientemente y se ha fortalecido la necesidad de establecer medidas de soporte por una serie de nociones relativas a las anormalidades e interacciones cardiorrespiratorias y metabólicas de la descompensación hepática.

Résumé La cirrhose est caractérisée par des séries de variations des fonctions physiologiques et de modifications cliniques qui impliquent des modalités d'adaptation anormale et fragile se traduisant par une résistance réduite à l'état de détresse ou peut se trouver le cirrhotique. Des mesures appropriées pour maintenir la stabilité physiologique ont un rôle principal en présence de ces facteurs défavorables. Elles ne doivent pas être considérées comme moins importantes que les mesures essentielles qui sont nécessaires pour traiter les complications et les modifications cliniques spécifiques. La relation entre l'altération des fonctions du foie et le développement des anomalies physiologiques précitées n'est pas parfaitement élucidée, cependant, nos connaissances de ce problème ont été récemment améliorées et le besoin de mesures adéquates de soutien est devenu manifeste en raison de séries acquises de notions concernant les anomalies cardio-respiratoires et métaboliques ainsi que les interactions de la décompensation hépatique.
  相似文献   
146.
Background: SARC-F and Mini Sarcopenia Risk Assessment (MSRA) questionnaires have been proposed as screening tools to identify patients at risk of sarcopenia. The aim of this study is to test the use of SARC-F and MSRA, alone and combined, as a pre-screening tool for sarcopenia in geriatric inpatients. Methods: 152 subjects, 94 men and 58 women, aged 70 to 94, underwent muscle mass evaluation by dual energy X-ray absorptiometry (DXA), muscle strength evaluation by handgrip, and completed the MSRA, SARC-F and Activity of daily living (ADL) questionnaires. Results: 66 subjects (43.4%) were classified as sarcopenic according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. The 7-item SARC-F and MRSA and 5-item MSRA showed an area under the curve (AUC) of 0.666 (95% confidence interval (CI): 0.542–0.789), 0.730 (95% CI: 0.617–0.842) and 0.710 (95% CI: 0.593–0.827), respectively. The optimal cut-off points for sarcopenia detection were determined for each questionnaire using the Youden index method. The newly calculated cut-off points were ≤25 and ≤40 for MSRA 7- and 5-items, respectively. The ideal cut-off for the SARC-F was a score ≥3. Applying this new cut-off in our study population, sensitivity and specificity of the 7-item MSRA were 0.757 and 0.651, and 0.688 and 0.679 for the 5-item MSRA, respectively. Sensitivity and specificity of SARC-F were 0.524 and 0.765, respectively. The combined use of the 7-item SARC-F and MSRA improved the accuracy in sarcopenia diagnosis, with a specificity and sensitivity of 1.00 and 0.636. Conclusion: 7-item SARC-F and MSRA may be co-administered in hospital wards as an easy, feasible, first-line tool to identify sarcopenic subjects.  相似文献   
147.
We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women.  相似文献   
148.
Neurosurgical Review - Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after...  相似文献   
149.
150.
The beta-endorphin-like-immunoreactivity (beta-ELI) has been evaluated both in plasma and in cerebrospinal fluid (CSF) in 30 patients during trans-sphenoidal surgery. Blood and liquoral samples were collected in five conditions: (1) "reference", (2) "pain", (3) "analgesia", (4) "end", and (5) "24th hour". A significant rise of both plasma and liquoral beta-ELI levels (p less than 0.00001 and p less than 0.08, respectively) when compared to basal ones occurred following the painful stimulation due to the divarication of the nasal mucosa by speculum. A significant decrease (p less than 0.01) was noticed for plasma concentrations at the third sample followed by a new significant increase at the end of the operation, (p less than 0.05 when compared to the third sample and p less than 0.01 when compared to the reference sample). In CSF, beta-ELI levels decreased at the third sample (p less than 0.01 when compared to the painful levels) and at the end of surgery (p less than 0.01, p less than 0.01 and p less than 0.05 vs first, second and third samples, respectively). Twenty-four hours after surgery either plasma and liquoral beta-ELI levels decreased (p less than 0.05). The modifications of the opiatergic system after acute painful stimuli should be, hence, characterized by an early rise followed by a progressive decrease of beta-ELI concentrations. The increase of plasma beta-ELI levels, at the end of surgery, could be due to pituitary manipulation with massive release in the peripheral blood.  相似文献   
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