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101.
102.
Environmental pollution in the form of particulate matter <2.5 μm (PM2.5) is a major risk factor for diseases such as lung cancer, chronic respiratory infections, and major cardiovascular diseases. Our goal was to show that PM2.5 eliciting a proinflammatory response activates the immune-pineal axis, reducing the pineal synthesis and increasing the extrapineal synthesis of melatonin. Herein, we report that the exposure of rats to polluted air for 6 hours reduced nocturnal plasma melatonin levels and increased lung melatonin levels. Melatonin synthesis in the lung reduced lipid peroxidation and increased PM2.5 engulfment and cell viability by activating high-affinity melatonin receptors. Diesel exhaust particles (DEPs) promoted the synthesis of melatonin in a cultured cell line (RAW 264.7 cells) and rat alveolar macrophages via the expression of the gene encoding for AANAT through a mechanism dependent on activation of the NFκB pathway. Expression of the genes encoding AANAT, MT1, and MT2 was negatively correlated with cellular necroptosis, as disclosed by analysis of Gene Expression Omnibus (GEO) microarray data from the human alveolar macrophages of nonsmoking subjects. The enrichment score for antioxidant genes obtained from lung gene expression data (GTEx) was significantly correlated with the levels of AANAT and MT1 but not the MT2 melatonin receptor. Collectively, these data provide a systemic and mechanistic rationale for coordination of the pineal and extrapineal synthesis of melatonin by a standard damage-associated stimulus, which activates the immune-pineal axis and provides a new framework for understanding the effects of air pollution on lung diseases.  相似文献   
103.
104.
The effect of a new non-steroid anti-inflammatory substance (bufexamac) in a special constituent was compared with that of 0.1% triamcinolone acetonide, 1% hydrocortisone cream, and placebo during a double-blind multicentre trial. The clinical effect of these four creams was studied in 193 patients receiving treatment for the following skin disorders: atopic dermatitis, allergic contact dermatitis, and non-allergic contact dermatitis, as well as dermatitis seborrheica. After 2 and 4 weeks' treatment, when 193 and 157 patients, respectively, were re-examined, the effect of triamcinolone acetonide and hydrocortisone cream was significantly better, than that obtained with bufexamac in the cream basis employed. On the other hand, no statistically significant difference in effect between bufexamac and placebo cream was observed.  相似文献   
105.

Purpose

In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.

Methods

The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival.

Results

Donor–recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer.

Conclusions

Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms.  相似文献   
106.
Experimental and clinical data demonstrate an antileukemia effect of acute graft-versus-host disease (aGVHD). In all, 58 pediatric patients with acute lymphoblastic leukemia (ALL) who had received an allogeneic bone marrow transplant (BMT) at our institution were retrospectively analyzed for a correlation between the development of aGVHD and leukemic relapse. Probability of relapse after 5 (3) years was 13% (7%) in patients developing grade II-IV aGVHD vs 30% in patients with grade 0 or I aGVHD. There was a trend for a difference of the point estimates at 3 years, but no overall significance because of an unusual late relapse. Moreover, we analyzed the impact of cyclosporin A (CsA) on aGVHD in a subgroup of 22 children who had received a matched sibling donor (MSD) BMT. An increased dose of CsA within the first 2 weeks after BMT led to decreased occurrence and severity of aGVHD (P=0.035). The cumulative CsA dose appeared to have more impact than the average CsA whole-blood levels within the first 2 weeks and than the CsA dose given from day 15 to 40. In this subgroup, no life-threatening aGVHD or death from aGVHD occurred. In all cases (6/22), leukemic relapse was the cause of death. We therefore suggest that there is a relation between dose of CsA and relapse rate in childhood ALL transplanted from a MSD.  相似文献   
107.
108.
Melatonin is an animal hormone as well as a signaling molecule in plants. It was first identified in plants in 1995, and almost all enzymes responsible for melatonin biosynthesis had already been characterized in these species. Melatonin biosynthesis from tryptophan requires four‐step reactions. However, six genes, that is, TDC, TPH, T5H, SNAT, ASMT, and COMT, have been implicated in the synthesis of melatonin in plants, suggesting the presence of multiple pathways. Two major pathways have been proposed based on the enzyme kinetics: One is the tryptophan/tryptamine/serotonin/N‐acetylserotonin/melatonin pathway, which may occur under normal growth conditions; the other is the tryptophan/tryptamine/serotonin/5‐methoxytryptamine/melatonin pathway, which may occur when plants produce large amounts of serotonin, for example, upon senescence. The melatonin biosynthetic capacity associated with conversion of tryptophan to serotonin is much higher than that associated with conversion of serotonin to melatonin, which yields a low level of melatonin synthesis in plants. Many melatonin intermediates are produced in various subcellular compartments, such as the cytoplasm, endoplasmic reticulum, and chloroplasts, which either facilitates or impedes the subsequent enzymatic steps. Depending on the pathways, the final subcellular sites of melatonin synthesis vary at either the cytoplasm or chloroplasts, which may differentially affect the mode of action of melatonin in plants.  相似文献   
109.
We present a patient who underwent sibling allogeneic BMT because of refractory Ph+ve ALL and remained BCR-ABL-positive after marrow grafting. Haemopoietic precursor cells were predominantly BCR-ABL-negative and of donor origin. In T cells an exclusively donor genotype was demonstrated. Despite donor leucocyte infusion (DLI), 20 weeks after BMT BCR-ABL fusion mRNA increased in semiquantitative polymerase chain reaction and leukaemic infiltration of the patient's bone marrow was seen. After a second course of DLI the patient achieved sustained molecular remission but he developed severe graft-versus-host disease (GvHD) and died from bacterial sepsis 9 months after DLI.  相似文献   
110.
Fairbanks  VF; Nepo  AG; Beutler  E; Dickson  ER; Honig  G 《Blood》1980,55(2):216-220
Two large and unrelated families were investigated for hereditary nonspherocytic hemolytic anemia associated with deficiency of erythrocyte glucose-6-phosphate dehydrogenase (G6PD). In both families, the kinetic and electrophoretic features of the G6PD variants resembled those of G6PD Chicago. Further investigation revealed that members of one of these families previously had been characterized as having the G6PD variants Chicago and Cornell. However, it is clear that each of these terms has been applied to the same variant in this single large kindred. In the second family, we describe a newly identified variant with unique characteristics, which we have designated G6PD Pea Ridge. G6PD Pea Ridge resembles G6PD Chicago but differs in electrophoretic mobility and in a few kinetic parameters. It exhibits an unusually high Ki for NADPH and thus appears to be insensitive to product inhibition. As other cases previously considered to be the Chicago variant become more fully characterized, this probably will be shown to be a heterogeneous group of variants.  相似文献   
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