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1.
M Müller J Grunewald C Olgart H?glund B Dahlén A Eklund H Stridh 《The European respiratory journal》2006,28(3):513-522
The increased number of lymphocytes in airways during an asthmatic response is believed to be the result of increased recruitment of these cells. However, it is possible that a decreased apoptotic rate could also contribute to the increased number. The aim of the present study was to investigate whether allergen airway provocation influences the apoptotic phenotype of lung and peripheral blood lymphocytes (PBL) in subjects with atopic asthma. Bronchoalveolar lavage (BAL) lymphocytes and PBL from 12 asthmatic subjects previously challenged with allergen (n = 7) or saline (n = 5) were exposed to the apoptotic stimulus tributyltin (TBT) in vitro and assayed for apoptosis. Airway allergen provocation resulted in decreased sensitivity of BAL lymphocytes to TBT-induced apoptosis, with 42.2% (range 33.9-62.5%) apoptotic cells before challenge versus 23.5% (range 15.3-42.4%) after challenge, while PBL were unaffected. The increased apoptosis resistance correlated with higher numbers of Bcl-2-expressing lymphocytes. Interestingly, baseline caspase-3-like activity was significantly elevated in viable BAL lymphocytes compared with viable PBL, and was unaltered by allergen exposure. In conclusion, allergen inhalation renders bronchoalveolar lavage lymphocytes more resistant to apoptosis while peripheral blood lymphocytes were not influenced at all, indicating that the apoptotic phenotype of airway lymphocytes may play a role in asthmatic inflammation. 相似文献
2.
C. Olgart Höglund J. Axén C. Kemi S. Jernelöv J. Grunewald C. Müller-Suur Y. Smith R. Grönneberg A. Eklund P. Stierna M. Lekander 《Clinical and experimental allergy》2006,36(8):982-992
BACKGROUND: Stress can aggravate the allergic inflammation, but determinants of disturbed immune regulation are largely unknown. OBJECTIVE: To determine systemic immunological, local inflammatory and functional airway responses to stress in healthy and atopic individuals. METHODS: Forty-one undergraduate students, 22 with allergy of whom 16 had asthma, and 19 healthy controls, were studied in a low-stress period and in association with a large exam. Subjects completed questionnaires on stress and health behaviours, underwent lung function tests, bronchial methacholine challenge, measurements of exhaled nitric oxide and urine cortisol. Blood cells were phenotyped, and cytokines from mononuclear blood cells were analysed. RESULTS: Perceived stress and anxiety increased in both groups during the exam period while cortisol increased only in the atopy group. Cytokine production decreased broadly in response to stress in both groups, which was paralleled by an increase in the proportion of regulatory T cells (CD4(+)CD45RO(+)CD25(bright)). Interestingly, atopic individuals, but not controls, reacted with a decreased T-helper type 1/T-helper type 2 (Th1/Th2) ratio and a decrease in natural killer (NK) cell numbers in response to stress. In control subjects only, exhaled nitric oxide decreased and forced expiratory volume in one second increased during stress. CONCLUSION: Atopic and non-atopic subjects shared some immune changes in response to stress, such as a dramatic decline in cytokines and an increase in the number of regulatory T cells in peripheral blood. However, other stress-induced immune changes were unique to atopic individuals, such as a skewed Th1/Th2 ratio and reduced NK cell numbers, indicating that some pathogenic mechanisms in atopics may be more strongly affected by stress than others. 相似文献
3.
H. Isoniemi J. Ahonen B. Eklund K. Höckerstedt K. Salmela E. von Willebrand P. Häyry 《Transplant international》1990,3(2):92-97
We have investigated the impact of triple drug immunosuppression on the occurrence of early inflammatory episodes, as detected by fine needle aspiration biopsy, and of episodes of clinical rejection during the immediate postoperative period. The prospective component of this study includes 128 consecutive first cadaveric renal transplant recipients receiving triple drug treatment consisting of azathioprine (Aza), cyclosporin (CyA) and methylprednisolone (MP). For controls we have used three historical groups: one immunosuppressed with Aza and MP (group A), another with CyA monotherapy (group B), and the third with CyA together with MP (group C) in equivalent drug dosages. On the average, 0.8 episodes of inflammation per patient were recorded during the immediate postoperative period of 30 days with triple drug treatment. This was significantly less than the 1.3 episodes in patients receiving Aza and MP (P<0.01), the 1.7 episodes in patients on CyA monotherapy (P<0.001), or the 1.6 episodes in patients receiving CyA together with MP (P<0.001). Although the first episode of inflammation commenced concurrently in each group and the peak intensity of inflammation was the same, the mean duration of inflammation was significantly shorter-2.7 days-under triple drug treatment than the 7.8–11.7 days for controls (P<0.001). The frequency of rejection episodes under triple treatment was also significantly lower-0.2 per patient-than the 0.8 per patient in controls (P<0.001). The first rejection episode occurred later in the triple drug treatment group-on the average, on day 15.2-than in the historical controls (on days 7.7–11.7). There was, however, no difference in the duration of rejection. There were no differences in patient survival between the four groups. Graft survival was 97% at 10 weeks for triple drug-treated recipients and 79%, 68%, and 87% for first grafts in groups A, B, and C, respectively. Disregarding a minor demographic bias for the triple drugtreated group with respect to preformed antibodies and preoperative dialysis treatment, the study suggests that the triple drug protocol, in the short run, is superior to any conceivable double drug combination or CyA monotherapy. 相似文献
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At our center, since 1982, a body mass index (BMI) of less than 30 has been a prerequisite for placing a patient on the waiting
list for renal transplantation. This decision was made because obese transplant recipients seemed to have a less than favorable
post-transplant outcome. The aim of this study was to evaluate whether this requirement is still justified. Forty-six patients
with a BMI above 30 underwent primary cadaveric renal transplantation between 1972 and 1993. For each of these obese patients,
five consecutive non-obese (BMI 20–25) control patients were selected. Patient and graft survival, causes of graft loss, and
acute rejection rate were evaluated for the two patient groups before and after the year 1982. Within the first 30 post-transplant
days, one patient (2 %) and 11 grafts (24 %) were lost in the group of obese patients whereas seven patients (3 %) and 36
grafts (16 %) were lost in the control group. Among the obese patients, renal circulatory complications were a major cause
of graft loss. In the period 1973–1981, the 1-year patient survival rate was 65 % among obese patients versus 75 % among controls
from 1982 to 1993, this was 90 % versus 93 %. From 1973 to 1981, the 1-year graft survival rate was 25 % among obese patients
versus 53 % among controls (P < 0.05); from 1982 to 1993, it was 68 % versus 84 % (P = NS). Multivariate analysis showed that the immunosuppressive regimen,
age of the patient, BMI, and cold ischemia time of the graft had a significant influence on graft survival. The acute rejection
rate within the first 30 days was 28 % among obese patients and 35 % among controls (P = NS). We conclude that a BMI below
or equal to 30 is still justified as a prerequisite for placement on the waiting list for renal transplantation, for despite
an overall improvement, the outcome of renal transplantation in obese patients remains worse than that in non-obese patients.
Received: 3 February 1997 Received after revision: 4 April 1997 Accepted: 8 April 1997 相似文献
7.
H. Isoniemi J. Ahonen B. Eklund K. Höckerstedt K. Salmela E. von Willebrand P. Häyry 《Transplant international》1990,3(1):121-127
Abstract. A prospective randomized study was conducted to evaluate the impact of four different conversion protocols on graft outcome in long-term follow-up. Between January 1986 and May 1987, 128 patients with first cadaveric kidney allografts were randomized at the time of transplantation to four treatment groups of 32 patients each, to be assigned 10 weeks post-transplantation. During the first 10 weeks, all patients received triple therapy with low-dose azathioprine (Aza), cyclosporin (CyA), and methylprednisolone (MP). After 10 weeks, one group continued with triple therapy (group A) while the three other groups received different combinations of two drugs, namely, Aza and CyA (group B), Aza and MP (group C), or CyA and MP (group D). Withdrawal of MP (group B) or especially of CyA (group C) was associated with 4/29 (14%) and 10/28 (36%) acute rejection episodes, respectively, for 60 days after conversion. All rejections were mild and reversible. There were no rejections after Aza withdrawal or in the group that continued on triple therapy during the corresponding time period. The most common reason for dropping out after withdrawal, for those patients who could not continue on the originally randomized medication, was azathioprine intolerance (n= 12). Five patients were switched back to triple therapy after CyA withdrawal due to rejection. Steroid intolerance was rare and CyA in low doses was very well tolerated. At 1 year there were no statistically significant differences in graft survival between groups A, B, C, and D-81 %, 88%, 88%, and 88%, respectively-or in patient survival-88%, 88%, 88%, and 97%, respectively. For those patients continuing with the originally randomized treatment protocol, there were no differences in patient or graft survival either, the means being 91% and 89%, respectively. The most common cause of death after withdrawal was cardiovascular in nature, and there were no more fatal infections under triple drug treatment than with double drug regimens. There were no statistically significant differences in mean serum creatinine values at 1 year. The median serum creatinine values for groups A, B, C, and D were 112, 132, 133, and 133 μmol/l, respectively. At 1 year the mean CyA dose in the groups that continued with CyA was 3. 5–4. 2 mg/kg per day and CyA concentrations were equal. 相似文献
8.
Tom Lindfors Carita Kvarnström Ari Ivaska 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):131-138
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI. 相似文献
9.
A significant decline (34.5%) in the suicide rate occurred in 1984–1988 throughout the USSR. The decline was observed shortly after the introduction of strict restrictions on the sale of alcohol. We tested the hypothesis that the restrictive alcohol policy in the first years of perestroika (June 1985) caused the fall in suicide rates in the former USSR. Data on alcohol consumption, violent death caused by external injury and poisoning (n= 916,315), death due to accidental alcohol poisoning (n= 77,837), suicide (n= 192,305) and death undetermined whether accidentally or purposely (n= 54,253) were analyzed for all former Soviet republics for 1984, 1986, 1988 and 1990. Men were chosen for the analysis, since men are more prone to abuse alcohol than women. Regression analysis with alcohol consumption as the independent variable and suicide rates and violent death rates as dependent variables shows that suicide and alcohol consumption were positively correlated as were violent death and alcohol consumption. In the republics with high alcohol consumption (Slavic and Baltic), suicide rates were also high. In the Caucasian republics, low alcohol consumption was associated with low suicide rates. For most republics, alcohol seems to explain more than 50% of suicides. Alcohol also has considerable explanatory value for violent death. Thus, a restrictive alcohol policy might be a way to reduce suicide and violent death. 相似文献
10.