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1.
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease.  相似文献   
2.
BACKGROUND: Major depression has been associated cross-sectionally with increased cell-mediated immune activation but causality has been difficult to establish. This study prospectively investigated the hypothesis that baseline level of immune activation predicts the development of depression during interferon-alpha (IFN-alpha) treatment. METHODS: Sixteen hepatitis C patients without psychiatric disorder underwent IFN-alpha treatment. Proinflammatory and anti-inflammatory cytokines were determined before starting treatment. Presence of a major depressive disorder (MDD) was assessed at baseline and several times during treatment. RESULTS: Baseline soluble interleukin-2 receptor (sIL-2r), interleukin-6 (IL-6), and interleukin-10 (IL-10) concentrations were significantly increased in the five subjects that developed MDD during treatment compared with those that did not, with standardized effect sizes of 1.08, 1.16, and 1.25, respectively, controlling for marijuana use, cigarette smoking, and baseline level of depressive symptoms. CONCLUSIONS: Results suggest that increased immune activation, rather than an epiphenomenon, is a causal risk factor for the development of MDD.  相似文献   
3.
Renal transplant recipients suffering from persistent diarrhea have been repeatedly reported to have increased tacrolimus (Tac) trough levels. This study aimed to explore this phenomenon in detail in 15 renal transplant recipients with diarrhea, whose immunosuppression consisted of corticosteroids, mofetil mycophenolate and Tac. Both hepatic and intestinal CYP3A4 and PGP activity, important determinants of Tac bioavailability, were assessed, together with global CYP activity and investigations for gastrointestinal infection, function and morphology. Global CYP, CYP3A4, PGP and trough/dose levels of Tac were compared with diarrhea-free controls. In addition, a pharmacokinetic study of Tac was performed in 11 patients affected by diarrhea versus 9 controls. As expected, diarrhea was associated with increased Tac trough levels. An even stronger, significant increase of dose-normalized Tac levels was observed between 90 and 360 min after Tac intake. Time to peak concentration and drug half-life, however, were not altered. In addition, a concomitant decrease (+/-50%) of intestinal PGP activity was noticed in patients with diarrhea. For global CYP, CYP3A4 and hepatic PGP activity no such differences were noted. This pattern was not influenced by the specific cause of diarrhea. These data strongly suggest that persistent diarrhea is associated with an increased oral bioavailability of Tac.  相似文献   
4.
The 3-methoxy-4-hydroxyphenylglycol (MHPG) flow, the creatinine flow in 24 h urine and the plasma creatinine level were determined in 42 psychiatric control patients. The creatinine clearance was calculated. The relationship between MHPG flow in 24 h urine and creatinine clearance, creatinine flow, 24 h urinary output, age, sex and weight of the patient were studied by means of single and multiple regression methods. The MHPG flow was significantly correlated with creatinine clearance (r= 0.597), creatinine flow (r = 0.646) and sex of the patient (rpb = 0.434). The variance of the MHPG flow can be explained by the regression with creatinine flow, age and urinary output for at maximum 51.5%. These variables have to be taken into account for the interpretation of data concerning the MHPG flow in subsequent experimental designs. The results of the measurements of the MHPG flow can best be expressed as the residual values obtained after partialling out the predictable component calculated by multiple regression with creatinine flow, age and 24 h urine output.  相似文献   
5.
Therapeutic drug monitoring generally focuses on the plasma compartment only. Differentiation between the total plasma concentration and the free fraction (plasma water) has been described for a number of limited drugs. Besides the plasma compartment, blood has also a cellular fraction which has by far the largest theoretical surface and volume for drug transport. It is with anti-cancer drugs that major progress has been made in the study of partition between the largest cellular blood compartment, i.e., erythrocytes, and the plasma compartment. The aim of the present review is to detail the progress made in predicting what a drug does in the body, i.e., pharmacodynamics including toxicity and plasma and/or red blood cell concentration monitoring. Furthermore, techniques generally used in anti-cancer drug monitoring are highlighted. Data for complex Bayesian statistical approaches and population kinetics studies are beyond the scope of this review, since this is generally limited to the plasma compartment only.  相似文献   
6.
The authors use injections of botulinum A toxin in treatment of facial spasms. 105 patients (70 patients with blepharospasm, 35 patients with hemispasm) were treated during 4 years. The toxin Wisconsin relieved spasms for an average of 10 weeks. Local complications such as ptosis and diplopia appeared in less than 1/5 of the cases. No general complications were observed. Repeated treatments are necessary. The authors noted a decrease of lacrimal secretion on the treated side in hemifacial spasm and concluded that botulinum A toxin injections could be used as a treatment of epiphora.  相似文献   
7.
Sir, In a recent Indian serosurvey [1], it was announced that ‘noreports of hantavirus infections in humans from India existed[before 2005]’. We wish to point out that serologicaland clinical evidence of hantavirus infection in India was alreadywell documented before 2005. From 1998 on, we screened leptospirosis-suspected cases in Indiafor the only known cosmopolitan hantavirus serotype, Seoul virus(SEOV). Wild rats are the reservoir  相似文献   
8.
Among the numerous causes of facial neuralgias, the painful dysfunction syndrome of the manducatory apparatus corresponds to a frequent etiology whose thorough study carried out by a multidisciplinary team over about 500 cases allowed their splitting into several evolutive clinical forms. At present, a number of these forms which are particularly painful, require a disk surgery (dislocation reduction, perforation suture, etc.) and if necessary an articular facet surgery (modelling condylectomy, surfacing, etc.). This study specifies the indications and prognosis for these surgical operations.  相似文献   
9.
Between January 1 and June 30, 1983, immunosuppressive drugs were administered in 20 renal transplant recipients undergoing 23 rejection episodes and in 3 patients with renal failure secondary to systemic disease. Legionella pneumophila, serogroup 1, pneumonia was diagnosed on 12/26 (47%) occasions. In an attempt to decrease this high rate, a program of erythromycin prophylaxis was instituted for every new patient who received immunosuppressive chemotherapy until eradication of the organism from the water supply could be realized. From July 1, 1983 to April 30, 1984, erythromycin prophylaxis (1.5-3 g/day by mouth) was administered during 39 episodes of high-dose immunosuppression (20 kidney graft recipients and 4 patients with systemic diseases); no cases of Legionnaire's disease were recorded. During the same period, erythromycin prophylaxis was withheld from 9 other high-dose immunosuppression episodes (7 kidney graft recipients and one patient with sarcoidosis); 5 cases of Legionnaire's disease occurred (56%) in this group. We conclude that erythromycin effectively protects immunocompromised patients in an environment contaminated with L pneumophila.  相似文献   
10.
BACKGROUND: The natural history of parathyroid function after successful renal transplantation (RT) and the factors predisposing to persistent hyperparathyroidism (HPT) are not well established. A better knowledge of these data may be helpful in the development of algorithms for optimal surveillance and treatment of HPT after successful RT. Our aim was to evaluate the post-transplant natural history of parathyroid function and calcium metabolism in patients with a functional renal graft and to identify risk factors for persistent HPT. METHODS: Charts of 1165 allograft kidney recipients transplanted between 1989 and 2000 were reviewed. Patients with an intact parathyroid hormone (iPTH) level available at the time of transplantation were identified. The charts of the latter patients were checked for a variety of demographic and clinical data, and all determinations of the iPTH concentration available since transplantation were recorded. Serum levels of calcium, phosphorus, alkaline phosphatases and creatinine, concurrently determined, were also registered. RESULTS: After an initial fall, iPTH levels showed a slow but steady decline towards the upper normal limit. The prevalence of persistent HPT, defined as an iPTH level > or =2.5 times the upper normal limit or the need for parathyroidectomy following transplantation, remained stable at approximately 17% up to 4 years after transplantation. Patients with persistent HPT had significantly elevated serum levels of iPTH, calcium and phosphorus at the time of RT, and had spent a longer time on dialysis. Post-transplant iPTH levels correlated significantly with transplant kidney function. CONCLUSION: Kidney transplant recipients with a high iPTH and calcium x phosphate product at the time of transplantation are at risk for persistent HPT especially when renal function is suboptimal. Therapy for persistent HPT, if considered, should be initiated 3 months post-transplantation since further spontaneous improvement of parathyroid function thereafter is limited.  相似文献   
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