小麦条锈病严重度分级标准的研究简报

小麦条锈病Puccinia striiformis West.严重度分级标准,目前在我国应用最多的是《农作物主要病虫测报办法》(以下简称《办法》)中的分级标准(分5％以下、5％、10％、25％、40％、65％、80％和100％8级)。这个分级标准,级别较多级距较乱,难于记忆。商鸿生等(1990)虽然作了改进(分级标准为1％、5％、10％、20％、40％、60％、80％和100％8级),但笔者认为这个标准仍较麻烦,对于在基层仍不适用。因此,笔者根据多年的实践经验,制定出既能反映真实情况,又简便易行的新的分级标准(定名为简易分级标准),即5％以下、10—20％、30—40％、50—80％、80—100％5级(参见分级标准图)。

T CELL REPERTOIRE COMPLEXITY IN SEVER COMBINED IMMUNODEFICIENCY PATIENTS AFTER BONE MARROW TRANSPLANTATION

Objective. To study thymus-dependent T cell development and T cell repertoire in human s ever com-bined immunodeficiencypatients after HLA-identical or haploid entical T cell-depleted allogeneic bone marrow transplantation.Methods .Blood samples were obtained from15SCID patients before transplantation and a t varying intervals thereafter.Quantitative competitive PCR assay and immunosco pe analysis of the T cell receptorVarepertoire were performed.Results. Before and within the first100days after transplantation,patients’ periphera l blood mononuclear cellpresented an oligoclonal or polyclonal skewed T cell repertoire,low T cell re-ceptor excision circlesvalues and pred ominance of CD45RO + T cell.In contrast,the presence of high numbers of CD45RA + T cells in bone marrowcirculation reconstituted SCID patients(>10 0days post-transplantation)correlated with active T cell production by the th ymus as revealed by high TREC values,and a polyclonal T cell repertoire demonst rated by a Gaussian distribution of Va-specific peaks.Conclusions.Within one year after BMT ,a normal T cell repertoire develops in SCID patients as a resu lt of thymic output.The T cell receptor diversity is highly and positively corr elated in these patients with TREC levels.

The difference of immunologic parameters between SARS patients of mild type and severe type

The aim of this study is to study the difference of immunologic parameters between severe acute respiratory syndrome （SARS） patients of mild type and severe type. Data including white blood cell （WBC） count, lymphocyte count, CD3, CD4 and CD8 T lymphocyte count, levels of C3, C4, ESR （erythrocyte sedimentation rate） and CRP （C-reactive protein） from 1291 patients with SARS in each week from onset of illness were recorded. The clinical progress of each sign was analysed and the difference between mild type and severe type was compared. Lymphocyte count, CD8 T lymphocyte count declined in the first two weeks and recovered from the third week, while CRP and CA- levels rose in the first week and then recovered gradually. Lymphocyte count and CD8 T lymphocyte count of severe cases were much lower than that of mild type （P 〈 0.01）, while CRP and CA- levels in severe type were much higher than that of mild type （P 〈 0.01）. Lymphocyte count, CD8 T lymphocyte count, CRP and CA- levels are useful signs for the diagnosis of SARS of severe type and are valuable for the evaluation of its severity.

The role of immunoinformatics in analysis of immune response against severe acute respiratory syndrome (SARS) coronavirus

In order to analyze the immune response to severe acute respiratory syndrome （SARS） coronavirus （SARS-CoV）, immunoinformatics and computational analyses were performed to study the immunological characters of SARS-CoV. According to the results of immunoinformatics analysis, the obvious variation of HLA-A2 associated T cell epitopes between SARS vires and HCoV-229E was found as follows： （1） Disappearance of HIA-A2 binding site; （2） variation sequence on the HLA-A2 associated epitope; （3） emergence of a new HLA-A2 associated epitope. The immunoinfomatics results were evidenced by T2 cell binding assay, ELISPOT and DimerX staining. In conclusion, immunoinformatics is a useful method to analyze the immunological character of a new finding infectious pathogen, like SARS-CoV. These findings of immunoinformatics are confirmed by lab and clinical experiments. In this case, immunoinformatics seems a very useful tool in the study of immune response and the evaluation of vaccine in infectious diseases, such as SARS.