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Oral lichen planus (OLP) is a chronic inflammatory disease displaying ultrastructural disturbances in epithelial hemidesmosomes. The expression of several key hemidesmosomal components in OLP as well as in normal buccal mucosa is, however, unknown. The aim of the study was therefore to examine intracellular and extracellular components involved in hemidesmosomal attachment, in OLP (n = 20) and in normal buccal mucosa (n = 10), by immunofluorescence. In normal buccal mucosa, laminin-α3γ2, integrin-α6β4, CD151, collagen α-1(XVII) chain, and dystonin showed linear expression along the basal membrane, indicating the presence of type I hemidesmosomes. Plectin stained most epithelial cell membranes and remained unphosphorylated at S4642. In OLP, most hemidesmosomal molecules examined showed disturbed expression consisting of discontinuous increases, apicolateral location, and/or intracellular accumulation. Plectin showed S4642-phosphorylation at the basement membrane, and deposits of laminin-α3 and laminin-γ2 were found within the connective tissue. The disturbed expression of hemidesmosomal proteins in OLP indicates deficient attachment of the basal cell layer, which can contribute to detachment and cell death of basal keratinocytes seen in the disease.  相似文献   
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Acquisition of antibodies against blood stage antigens is crucial in malaria immunity and the Plasmodium falciparum antigen Pf332, which is present in close association with the infected red blood cell membrane, is one such antigen. In this study, the antibody response to a Duffy binding like fragment of Pf332, termed Pf332-DBL was investigated in sera from naturally exposed individuals living in Dielmo village, Senegal, with regard to immunoglobulin classes (IgG, IgM, IgE) and IgG subclasses (IgG1–4). While the levels of IgM, IgG, IgG1 and IgG2 only displayed a moderate trend to increase with age, Pf332-DBL specific IgG3 levels increased significantly in the older villagers. In multivariate analysis, when controlling for confounding factors, and in a linear model with a Poisson distribution, anti-Pf332-DBL IgG3 as well as the ratio of cytophilic to non cytophilic anti-Pf332-DBL antibodies were found significantly associated with a reduced risk of malaria attack. This association was also present when the IgG3:IgG1 ratio was tested. Finally, two subgroups of villagers with the same mean age, were delineated by IgG3 concentrations either lower or higher than the median value. A total of 45.2% of the individuals with low anti-Pf332-DBL-IgG3 levels but only 21.4% of the villagers in the group with high levels of such antibodies had a clinical malaria attack during a period of 3 years of continuous follow-up after the blood sampling. In conclusion, Pf332-DBL induces naturally the acquisition of antibodies, and Pf332-DBL-specific IgG3 appears to be associated with protection against malaria in this endemic setting.  相似文献   
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肝纤维化时血浆内皮素含量的动态观察   总被引:2,自引:0,他引:2  
目的测定肝纤维化时血浆内皮素(ET)含量的动态改变.方法36只家兔随机分为正常组、病理组.于感染血吸虫尾蚴后第70,100,130天,每组随机选6只取血和肝分别作血浆ET含量和肝组织羟脯氨酸(HYP)含量测定.结果正常组各阶段间ET和HYP含量均无显著性差异(P>0.05),病理组血浆ET含量和肝HYP与肝胶原纤维分布面积百分比均随着病程延长而增加.结论结果提示肝纤维化时血浆ET含量的增加可能参与了肝组织纤维化的进展.  相似文献   
6.
Glucocorticoid receptor (GR) levels were quantitated in leukemic blasts from bone marrow aspirates of 249 children with acute lymphoblastic leukemia (ALL) who were entered on two St. Jude Total Therapy Studies. Of these, 235 were evaluable for analysis of the relation of GR levels to clinical outcome. For the 42 patients in the earlier Total Therapy Study IX, lower GR levels (<16,000 sites/cell) were associated with both induction failure and more frequent relapse (p <0.01) [Cancer Research, Vol. 42, p. 4801 (1982)]. When patients with ‘high-risk’ features (leukocyte count >100 × 103/mm3, positive erythrocyte rosette test, central nervous system involvement, and mediastinal mass) were excluded, lower receptor levels were still associated with early and more frequent relapse (p <0.02). The other 193 evaluable patients were consecutively admitted to Total Therapy Study X, in which patients with ‘standard-risk’ or ‘high-risk’ features were assigned to separate protocols — XS and XH, respectively. Induction chemotherapy in both protocols consisted of prednisone, vincristine and l-asparaginase; patients in the XH protocol received additional epipodophyllotoxin (VM-26) and cytosine arabinoside twice a week for 2 weeks preceding the conventional induction therapy. To compare the prognostic value of GR level in Study X with that of Study IX (which included both ‘high-risk’ and ‘standard-risk’ patients but did not separate them into different protocol groups), children in the XH and XS protocols were analysed together. The proportion of patients with ‘standard-risk’ features was the same in the two studies: 69% in Study IX and 73% in Study X. In Study X, which had a significantly better treatment result (p <0.001), lower receptor levels were not associated with induction failure, but were correlated with more frequent relapse (p <0.05). When patients in XH and XS protocols were analysed separately, however, receptor levels were no longer related to treatment outcome. Thus, GR level in childhood ALL has prognostic value, but it is not an independent factor and its importance is related to the efficacy of treatment.  相似文献   
7.
We determined retrospectively the frequency and risk of hyperglycemia in 421 children with leukemia who had received L-asparaginase and prednisone as part of their remission induction therapy. Forty-one patients (9.7%) developed this complication, 39 within one week after the first dose of L-asparaginase. Hyperglycemia resolved in all patients and in 32 before the end of the four-week induction period. Age, obesity, and Down syndrome each had a significant bearing on the frequency of hyperglycemia. Children 10 years of age or older were more likely to develop the complication than were younger children. When more than one factor was present in a child, the risk of hyperglycemia increased significantly. A family history of diabetes mellitus also appeared related to an increased risk of hyperglycemia. Childhood leukemia patients with any of the risk factors identified here should be closely monitored for glucosuria while receiving prednisone and L-asparaginase for remission induction.  相似文献   
8.
We report the development and characterization of SJ-9A4, a monoclonal antibody (MoAb) produced against common acute lymphoblastic leukemia (C-ALL) cell lines. SJ-9A4 reacted with C-ALL, B-cell chronic lymphocytic leukemia (B-CLL), platelets and C-ALL neuroblastoma (NB) and the K562 cell lines. It had no significant reactivity with erythrocytes, granulocytes, circulating T or B lymphocytes, monocytes, granulocytic cell lines or a Ewing's sarcoma cell line. SJ-9A4 was shown to recognize the same region as two other MoAb to the p24 antigen, BA-2 and DU-ALL-1, as demonstrated by their ability to inhibit the binding of labeled SJ-9A4 to NALM-1 and NB cells. Other MoAb: J5, PI 153/3 and monoclonal anti-HLA-DR antibodies gave no inhibition. A solid phase indirect radioimmunometric assay (IRA) was developed which enabled the detection of P24 from C-ALL cells, utilizing its ability to bind the Ricinus communis agglutinin (RCA1) or wheat germ agglutinin (WGA) and SJ-9A4 simultaneously. When BA-2 and DU-ALL-1 were used in place of SJ-9A4, similar IRA results were obtained. Using the RCA1/SJ-9A4-IRA, P24 from as few as 1.6 X 10(4) cells of a C-ALL cell line could be detected; however, similar extracts of NB cell lines were negative despite high levels of SJ-9A4 binding to intact cells. The presence of P24 in NB extracts was demonstrated by (1) preincubation of NB extracts with SJ-9A4 which blocked MoAb binding to P24 and (2) immunoadsorption of P24 from solubilized membranes of 35S-methionine (met) labeled NB cells. Treatment of NB cells with neuraminidase did not result in IRA binding when either RCA1 or WGA were used as the solid phase lectin indicating that the differences in lectin affinity are not due to over sialation of NB membrane glycoproteins. These findings demonstrate a difference in the glycosylation of P24 from C-ALL and NB cells.  相似文献   
9.
Treatment for the child with cancer has increasingly been on a rational rather than an empiric basis. An understanding has developed of the importance for determining clinical and laboratory features present at diagnosis as an aid not only to establish a prognosis but also to design specific treatment regimens. A system has been developed for bringing new chemotherapeutic agents into clinical trials as effectively as possible. Through both clinical and laboratory studies, an increasing understanding of the biology of cancer is being developed. This understanding will provide the basis for more rational treatment programs in the future. Physicians of different specialty interests have learned to work together to develop coordinated programs of treatment so important to optimal care. By far the most important lesson learned, however, is that cancer in children is not of necessity a fatal disease, even when dissemination has occurred. For the furture, it will be necessary to develop even more effective methods of treatment, and research must provide a better understanding of this disease that may offer the opportunity for prevention, which, after all, is the number one interest of the pediatrician.  相似文献   
10.
目的 构建包含恶性疟原虫Pf332基因片段的分泌型、非分泌型真核表达重组质粒。方法 从FCCl/HN株基因组DNA中PCR扩增P1332基因片段,P332-RO、P332-R1和P332-R2;用PCR扩增法合成鼠IgG轻链信号肽的编码序列。用定向克隆法分别构建分泌型重组质粒pcDNA3-s—P332-R0、pcDNAl-s—P332-R1、pcDNA3-s—P332-R2和非分泌型重组质粒pcDNA3-s—P332-R0、pcDNA3—s—P332-R1、pcDNA3—s—P332-R2。阳性克隆的重组质粒DNA经酶切、PCR扩增及测序鉴定。结果 PCR扩增得到特异的FCCl/HN株P1332基因片段,P332-R0、P332-R1、P332-R1,大小分别为489、429和393bp。用PCR扩增法合成63bp的Balb/c小鼠IgG轻链信号肽的编码序列。酶切、PCR及测序鉴定表明获得了正确的含P1332基因片段的分泌型、非分泌型重组质粒。结论 成功构建分别包含恶性疟原虫P1332基因片段-1332-R0、P332-R1和P332-R2的分泌型、非分泌型真核表达重组质粒。  相似文献   
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