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31.
Familial hemophagocytic lymphohistiocytosis (FHL) is a rare, rapidly fatal, autosomal recessive immune disorder characterized by uncontrolled activation of T cells and macrophages and overproduction of inflammatory cytokines. Linkage analyses indicate that FHL is genetically heterogeneous and linked to 9q21.3-22, 10q21-22, or another as yet undefined locus. Sequencing of the coding regions of the perforin gene of eight unrelated 10q21-22-linked FHL patients revealed homozygous nonsense mutations in four patients and missense mutations in the other four patients. Cultured lymphocytes from patients had defective cytotoxic activity, and immunostaining revealed little or no perforin in the granules. Thus, defects in perforin are responsible for 10q21-22-linked FHL. Perforin-based effector systems are, therefore, involved not only in the lysis of abnormal cells but also in the down-regulation of cellular immune activation.  相似文献   
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33.
Broomrapes (Orobanche spp.) are aggressive and damaging parasitic weeds which have a tremendous impact on agriculture in East Africa, the Mediterranean region and the Middle East. Despite the availability of technologies to control broomrapes in economically important crops, Orobanche infestation continues to increase, threatening the livelihoods of millions of farmers. Many of the technologies developed have not been effectively disseminated and there has been little or zero adoption by farmers—who continue to use ineffective management practices that exacerbate the problem. The adaptation and dissemination of appropriate management practices are major priorities in broomrape control. However, such work must take into consideration the specific socio-economic characteristics of individual farming systems. Orobanche is a community threat and effective management requires a community-based integrated management approach. Recognizing the central role of farmers in parasitic weed management, a technical cooperation project (TCP) involving FAO, ICARDA and seven countries in the Near East and North Africa (NENA) region was implemented to improve the dissemination of knowledge and skills by using a farmer field school approach: a form of education that uses experiential learning methods to build farmers’ expertise. This paper reviews conventional Orobanche research and development approaches, and highlights weaknesses in the management of the parasitic weed using these approaches as opposed to participatory approaches. The benefits and challenges of participatory farming system approaches in relation to integrated broomrape management (IBM) are also discussed. Lessons learned from achieving community ownership of, and institutional support for, IBM could be applied to other sectors (e.g. public health) in which there is a need for institutional learning and reform. Recommendations are made that include regional collaboration within the framework of a proposed Near East and North Africa Orobanche Management Network (NENAOMAN).  相似文献   
34.
Background: Evaluation of the potential efficacy and safety of combination therapies for advanced soft tissue sarcomas (STS) has increased substantially after approval of trabectedin and pazopanib. Trabectedin’s introduction in Europe in 2007 depended mainly on its activity in so-called L-sarcomas (liposarcoma and leiomyosarcoma); combination of trabectedin with other chemotherapies used in STS seems of particular interest. Methods: We initiated within the German Interdisciplinary Sarcoma Group (GISG) a phase I dose escalating trial evaluating the combination of trabectedin and gemcitabine in patients with advanced and/or metastatic L-sarcomas (GISG-02; ClinicalTrials.gov NCT01426633). Patients were treated with increasing doses of trabectedin and gemcitabine. The primary endpoint was to determine the maximum tolerated dose. Results: Five patients were included in the study. Two patients were treated on dose level 1 comprising trabectedin 0.9 mg/m2 on day 1 and gemcitabine 700 mg/m2 on days 1 + 8, every 3 weeks. Due to dose-limiting toxicity (DLT) in both patients (elevated transaminases and thrombocytopenia), an additional three patients were treated on dose level −1 with trabectedin 0.7 mg/m2 plus gemcitabine 700 mg/m2. Of these three patients, two demonstrated another DLT; therefore, the trial was stopped and none of the dose levels could be recommended for phase II testing. Conclusion: The GISG-02 phase I study was stopped with the conclusion that the combination of gemcitabine and trabectedin is generally not recommended for the treatment of patients with advanced and/or metastatic leiomyosarcoma or liposarcoma. Also, this phase I study strongly supports the necessity for careful evaluation of combination therapies.  相似文献   
35.
Cytoplasmic male sterile system in ridge gourd has been converted to cytoplasmic genetic male sterile (CGMS) system through the development of analogues of male sterile (MS) line, maintainer line and fertility restorer line. These lines were developed by crossing the MS mutant, regenerated through in vitro culture, with monoecious pollen parents Deepthi, Haritham, LA 101, CO 2, IC 92761 and IC 92685. All hybrids and the BC1 generation developed by crossing with the recurring pollen parents Deepthi, Haritham and LA 101 were male sterile. Male sterile BC1 plants have been advanced to BC6 generation and the parental line LA 101 was proved to be a successful maintainer line, producing male sterile progeny in successive back cross generations. Analogue of cytoplasmic male sterile line, MS LA 101, was developed through back crossing and on crossing with fertility restorer lines Arka Sumeet and LA 102, this line excelled as female parent, resulting heterotic combinations. Mitochondrial marker rpS14 and SCAR Tm-53 were identified to yield male sterility specific markers whereas SSR marker 18956 has generated the male fertility specific marker. These primers are recommended for marker assisted selection of ridge gourd, for utilizing male sterility for hybrid seed production and for developing A, B and C lines in CGMS system.  相似文献   
36.
Enhanced root growth in plants is fundamental to improve soil water exploration and drought tolerance. Understanding of the variance components and heritability of root biomass allocation is key to design suitable breeding strategies and to enhance the response to selection. This study aimed to determine variance components and heritability of biomass allocation and related traits in 99 genotypes of wheat (Triticum aestivum L.) and one triticale (X. Triticosecale Wittmack) under drought-stressed and non-stressed conditions in the field and greenhouse using a 10?×?10 alpha lattice design. Days to heading (DTH), days to maturity (DTM), number of tillers (NPT), plant height (PH), spike length (SL), shoot and root biomass (SB, RB), root to shoot ratio (RS), thousand kernel weight (TKW) and yield (GY) were recorded. Analyses of variance, variance components, heritability and genetic correlations were computed. Significant (p?<?0.05) genetic and environmental variation were observed for all the traits except for spike length. Drought stress decreased heritability of RS from 47 to 28% and GY from 55 to 17%. The correlations between RS with PH, NPT, SL, SB and GY were weaker under drought-stress (r?≤???0.50; p?<?0.05) compared to non-stressed conditions, suggesting that lower root biomass allocation under drought stress compromises wheat productivity. The negative association between GY and RS (r?=???0.41 and ??0.33; p?<?0.05), low heritability (<?42%) and high environmental variance (>?70%) for RS observed in this population constitute several bottlenecks for improving yield and root mass simultaneously. However, indirect selection for DTH, PH, RB, and TKW, could help optimize RS and simultaneously improve drought tolerance and yield under drought-stressed conditions.  相似文献   
37.
The rate of gene flow is greatly affected by the ability of a species to move from one location to another. In Ethiopia the presence of diverse agro-ecological zones, climatic features, rugged mountains and isolated valleys affected the seed-mediated gene flow among regions. Hence, this study was aimed at investigating and detecting presence of any gene barriers and genetic differentiation among regions. Thus, the study was proposed to test whether the high genetic diversity of barley in Ethiopia was due to a reduced gene flow resulting from geographic barriers and/or effects of human activities. A total of 199 barley landraces collected from 10 different geographic regions and altitudes of Ethiopia were analyzed for 15 molecular markers. A barrier analysis was conducted to identify any geographic areas with pronounced genetic discontinuity between the regions that can be interpreted as barriers to gene flow. The result obtained from analysis of molecular variances indicated high genetic variation within regions rather than between regions. Despite high gene flow among regions, we were able to detect genetic discontinuity due to landscape and human mobility for certain barley growing areas. Hence, it was postulated that these barriers have to be considered in genetic resource sampling strategies.  相似文献   
38.
Multiple statistical analyses of terminal restriction fragment length polymorphism (T-RFLP) data were used to screen and identify bacterial populations involved in general disease suppression in an organically managed soil. Prior to sampling three different management strategies (i.e. mixed hay (H), tilled fallowing and open-field vegetables production) were used during the transition from conventional to organic farming, with and without compost amendment. The H transition strategy consistently led to the lowest damping-off disease incidence on two different crops in separate greenhouse and field experiments. Bacterial population structure in bulk soil and the rhizosphere of both crops was characterized using T-RFLP analyses of amplified 16S rDNA sequences. First, principal component analysis (PCA) revealed changes in the relative abundance of bacterial terminal restriction fragments (TRF) in response to transition strategy and/or compost amendment in eight different experimental contexts. In each context, a different subset of TRF substantially contributed to the variation along the first two principal components. However, terminal restriction fragment M148 contributed significantly to the observed variation in 6 out of the 8 experiments, and moderately in the remaining 2 experiments. As a second approach, nonparametric analyses of variance revealed that the relative abundance of TRF differed among treatments. While the responsive subsets identified varied somewhat by experimental context, M137, M139 and M141 were more abundant in samples from the H transition strategy in multiple experimental contexts. Subsequent correlation analyses revealed that TRF associated with disease suppressive treatments (i.e. H with and without compost) were frequently negatively correlated with damping-off disease incidence. As a group, these TRF were disproportionately associated with lower disease levels further indicating their role in disease suppression. Interestingly, in silico analysis of the bacterial 16S rDNA sequence database revealed that the TRF identified in this study (e.g. M137, M139, M141, and M148) might correspond to well-characterized genera of bacterial biological control agents.  相似文献   
39.
The aim of the present study was to evaluate acellular dermal matrix (ADM) of rat origin for the repair of ventral hernia in horses. The skin from rats, to be used as a graft, was de-epithelialized using hypertonic solution and further decellularized with 0.5% sodium dodecyl sulfate and 0.25% tri-(n-butyl)-phosphate. Under general anesthesia, the hernial ring was exposed and repaired with the ADM graft using inlay graft technique. Blood samples were collected at postimplantation days 0, 15, and 30 and were used for sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis to assess the serum protein concentration of the animals, as well as for gelatin zymography for the identification of matrix metalloproteinases. All animals had an uneventful recovery without clinical signs of wound dehiscence, infection, or recurrence of hernias during 6-month follow-up period. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of concentration of the serum proteins revealed that this was increased at day 15 and had decreased again at day 30. Gelatin zymography showed only one major band of 92 kDa in the serum of all the horses with the implant, but the relative amount of 92 kDa was higher at day 15 as compared with day 0 and day 30. It may be concluded that ADM of rat origin can be used safely in horses for repair of ventral hernia.  相似文献   
40.
Huang  Tan  Chang  Munday  Mathew  Ngoh  & Kwang 《Journal of fish diseases》2001,24(3):135-141
The coat protein encoded by the nodavirus RNA2 gene originally isolated from greasy grouper, Epinephelus tauvina , was cloned, expressed as a recombinant polyhistidine-tailed fusion protein and characterized by immunoblot analysis. The purified recombinant protein was used to develop an indirect enzyme-linked immunosorbent assay (ELISA) to detect body exudate and plasma antibodies against the coat protein in both experimentally infected and commercial barramundi. In addition, the nucleotide sequence was employed to develop a RT–PCR detection assay based on the T4 region. The results showed that the virus could be detected as early as 3 days post-infection by RT–PCR while antibodies against the recombinant coat protein were detectable on day 6 post-infection. Among 112 commercial barramundi samples collected from October 1999 to April 2000, 9% showed positive ELISA results which were further verified by Western blot.  相似文献   
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