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991.
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993.
The treatment of myeloid leukaemia has progressed in recent years with the advent of donor leukocyte infusions (DLI), haemopoietic stem cell transplants (HSCTs) and targeted therapies. However, relapse has a high associated morbidity rate and a method for removing diseased cells in first remission, when a minimal residual disease state is achieved and tumour load is low, has the potential to extend remission times and prevent relapse especially when used in combination with conventional treatments. Acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) are heterogeneous diseases which lack one common molecular target while chronic myeloid leukaemia (CML) patients have experienced prolonged remissions through the use of targeted therapies which remove BCR-ABL+ cells effectively in early chronic phase. However, escape mutants have arisen and this therapy has little effectivity in the late chronic phase. Here we review the immune therapies which are close to or in clinical trials for the myeloid leukaemias and describe their potential advantages and disadvantages.  相似文献   
994.
Diabetic nephropathy (DN) is one of the most severe complications of diabetes and remains the largest cause of end-stage renal disease in the Western world. Treatment options are limited and novel therapies that effectively slow disease progression are warranted. Previous work suggested that treatment with CTLA4-Ig (abatacept), a molecule that binds and blocks B7-1 and is licensed for the treatment of rheumatoid arthritis, could ameliorate DN. This study was designed to assess whether B7-1 signalling constitutes a promising therapeutic pathway for DN. Mice injected with streptozotocin (STZ) were treated with abatacept and glycemia and renal function were assessed. No differences were found in diabetes progression, albumin excretion rates or albumin/creatine ratios, while mesangial expansion was unaltered at endpoint. Except for increased renal CCL5, treatment did not affect a panel of gene expression endpoints reflecting early fibrotic changes, inflammation and kidney injury. Finally, abatacept treatment effectively reduced the accumulation of activated CD4+ T cells in the kidney, suggesting that renal T cell inflammation is not a driving factor in the pathology of the STZ model. In conjunction with the recent data discounting the expression of B7-1 on podocytes, our present data do not support a role for abatacept in DN treatment.  相似文献   
995.
Clostridium botulinum produces botulinum neurotoxin (BoNT) as a large toxin complex associated with nontoxic-nonhemagglutinin (NTNHA) and/or hemagglutinin components. In the present study, high-level expression of full-length (1197 amino acids) rNTNHA from C. botulinum serotype D strain 4947 (D-4947) was achieved in an Escherichia coli system. Spontaneous nicking of the rNTNHA at a specific site was observed during long-term incubation in the presence of protease inhibitors; this was also observed in natural NTNHA. The rNTNHA assembled with isolated D-4947 BoNT with molar ratio 1:1 to form a toxin complex. The reconstituted toxin complex exhibited dramatic resistance to proteolysis by pepsin or trypsin at high concentrations, despite the fact that the isolated BoNT and rNTNHA proteins were both easily degraded. We provide definitive evidence that NTNHA plays a crucial role in protecting BoNT, which is an oral toxin, from digestion by proteases common in the stomach and intestine.  相似文献   
996.
Spatial processes could play an important role in density-dependent population regulation because the disproportionate use of poor quality habitats as population size increases is widespread in animal populations-the so-called buffer effect. While the buffer effect patterns and their demographic consequences have been described in a number of wild populations, much less is known about how dispersal affects distribution patterns and ultimately density dependence. Here, we investigated the role of dispersal in spatial density dependence using an extraordinarily detailed dataset from a reintroduced Mauritius kestrel (Falco punctatus) population with a territorial (despotic) breeding system. We show that recruitment rates varied significantly between territories, and that territory occupancy was related to its recruitment rate, both of which are consistent with the buffer effect theory. However, we also show that restricted dispersal affects the patterns of territory occupancy with the territories close to release sites being occupied sooner and for longer as the population has grown than the territories further away. As a result of these dispersal patterns, the strength of spatial density dependence is significantly reduced. We conclude that restricted dispersal can modify spatial density dependence in the wild, which has implications for the way population dynamics are likely to be impacted by environmental change.  相似文献   
997.
Direct moxibustion is an important and widely used treatment method in traditional medical science. The use of a mathematical method to analyse direct moxibustion treatment is necessary and helpful in exploring the new direct moxibustion instruments and their standardisation. Thus, this paper aims to use a mathematical method to study direct moxibustion in skin to demonstrate a direct relationship between direct moxibustion and skin stimuli. In this paper, the transient thermal response of skin layers is analysed to study direct moxibustion using the data got from standardised method to measure the temperature of a burning moxa cone. Numerical simulations based on an appropriate finite element model are developed to predict the heat transfer, thermal damage and thermal stress distribution of barley moxa cones and jujube moxa cones in the skin tissue. The results are verified by the ancient literatures of traditional Chinese medicine and clinical application, and showed that mathematical method can be a good interface between moxa cone and skin tissue providing the numerical value basis for moxibustion.  相似文献   
998.
Arbuscular mycorrhizal fungi (AMF) have been observed in deep soil layers in arid lands. However, change in AMF community structure with soil depth and vertical distributions of the other root-associated microorganisms are unclear. Here, we examined colonization by AMF and dark septate fungi (DSF), as well as the community structure of AMF and endophytic fungi (EF) and endophytic bacteria (EB) in association with soil depth in a semiarid desert with shallow groundwater. Roots of Sabina vulgaris and soils were collected from surface to groundwater level at 20-cm intervals. Soil chemistry (water content, total N, and available P) and colonization of AMF and DSF were measured. Community structures of AMF, EF, and EB were examined by terminal restriction fragment length polymorphism analysis. AMF colonization decreased with soil depth, although it was mostly higher than 50%. Number of AMF phylotypes decreased with soil depth, but more than five phylotypes were observed at depths up to 100 cm. Number of AMF phylotypes had a significant and positive relationship with soil moisture level within 0-15% of soil water content. DSF colonization was high but limited to soil surface. Number of phylotypes of EF and EB were diverse even in deep soil layers, and the community composition was associated with the colonization and community composition of AMF. This study indicates that AMF species richness in roots decreases but is maintained in deep soil layers in semiarid regions, and change in AMF colonization and community structure associates with community structure of the other root-associated microorganisms.  相似文献   
999.
The degradation of the 3'-untranslated regions (UTRs) of vitellogenin, cyanoprotein alpha, and cyanoprotein beta from the bean bug, Riptortus clavatus, was analyzed in vitro. The degradation pattern was similar for all three RNAs, with a high degradation rate in non-diapausing adult insects and no degradation in the fifth instar nymphs and in diapausing adults, and was not correlated with the expression levels of these three proteins. Proteins binding to the 3'-UTRs were detected in polysomal and cytosolic extracts. These factors, however, were present in all developmental stages. The abundance of the polysomal factor showed little variation, but the cytosolic factor was enriched in adult insects. Cross-competition experiments demonstrated that the same factors bound to all three RNAs with similar affinity. The pattern of degradation, presence of the binding factors in all stages, and their inability to distinguish between the target sequences indicate that the 3'-UTRs do not participate in controlling the expression of these three proteins.  相似文献   
1000.
Transthyretin related amyloidosis is a nosological entity that leads to disability, diminished quality of life, all stages of chronic kidney disease and eventually death. Podocytes are polarized, highly differentiated epithelial cells important for proper nephron function. In the present study we investigated whether deposited TTRVal30Met (TTRV30M) molecules could be localized within podocytes in situ under the effect of different housing conditions (i.e. specific pathogen free [SPF] vs. non-SPF). Murine renal glomeruli from human TTRV30M (hTTRV30M) transgenic mice were examined via direct and indirect immunofluorescence techniques for the presence of hTTRV30M, murine serum amyloid P, activated caspase-3 and NPHS1. Association strength and amount of colocalization for NPHS1?ChTTRV30M, NPHS1-activated caspase-3, hTTRV30M-murine serum amyloid P were estimated. Localization of hTTRV30M in podocytes was demonstrated by immuno-electron microscopy. Renal hTTRV30M gene and NPHS1 gene expression levels were estimated. Non-SPF transgenic mice showed increased glomerular hTTRV30M deposition compared to their SPF counterparts. Furthermore increased podocytic localization of hTTRV30M was noticed in non-SPF mice. Glomerular caspase-3 activation was increased only in the non SPF housing conditions. Podocytic caspase-3 activation was increased in SPF and in non-SPF transgenic mice when compared to non transgenic controls. Environmental conditions influence glomerular deposition and podocytic localization of hTTRV30M. In this context increased caspase-3 activation occurred.  相似文献   
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