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91.
Syringolides are water-soluble, low-molecular-weight elicitors that trigger defense responses in soybean cultivars carrying the Rpg4 disease-resistance gene but not in rpg4 cultivars. 125I-syringolide 1 previously was shown to bind to a soluble protein(s) in extracts from soybean leaves. A 34-kDa protein that accounted for 125I-syringolide 1 binding activity was isolated with a syringolide affinity-gel column. Partial sequences of internal peptides of the 34-kDa protein were identical to P34, a previously described soybean seed allergen. In soybean seeds, P34 is processed from a 46-kDa precursor protein and was shown to have homology with thiol proteases. P34 is a moderately abundant protein in soybean seeds and cotyledons but its level in leaves is low. cDNAs encoding 46-, 34-, and 32-kDa forms of the soybean protein were cloned into the baculovirus vector, pVL1392, and expressed in insect cells. The resulting 32- and 34-kDa proteins, but not the 46-kDa protein, exhibited ligand-specific 125I-syringolide binding activity. These results suggest that P34 may be the receptor that mediates syringolide signaling.  相似文献   
92.
Aircraft disinsection with aerosol insecticides during flight has generally been held to be inadvisable because it was assumed that the insecticides would be rapidly removed by the cabin air-conditioning system. We have developed protocols to deliver 2% d-phenothrin at a dose of 35 g per 100 m3 in various aircraft, and trials undertaken on Boeing 747 and 767 aircraft showed that their air-conditioning systems do not preclude effective disinsection. Mortality levels of 100% for Culex quinquefasciatus and Musca domestica test insects were recorded under normal operating conditions during routine scheduled passenger flights with disinsection procedures undertaken at "blocks-away" or at "top-of-descent". As a result, "top-of-descent" disinsection has been introduced as the recommended procedure for aircraft landing in Australia.  相似文献   
93.
Many youth, their parents, and social services regard the unification of the family as the most desirable outcome for youth in out-of-home placements. This goal is often difficult to achieve because the families of these troubled/troubling youths are often severely dysfunctional, with multiple problems. A group process model for serving natural parents of youth in placement is described which, in conjunction with one-on-one interactions with professionals, appears to have a positive impact on these families and on youths' return home. Group components that seem particularly important are described, including attendance by invitation only, public commitment to attend and participate, reminder prompts, transportation support, babysitting support, refreshments, opportunity to visit with their child, defined staff roles, an empowering approach, and starting where the parent is. The group process maintained a relatively high level of both attendance and participation by the targeted parents. Participants tended to achieve most goals that they set in the group. Our experience indicates that interventions with natural parents of troubled youth can enable even a very dysfunctional family to improve enough to receive youth back into their home.The authors are grateful for the assistance of Sharon Estill, Jim Bernardo, Anita Mentzer, Dave Walker, and Suni Dague-Lyman for assistance in collecting the data reported here. Debbie Buchanan and others have been a great assistance in transporting families.  相似文献   
94.
Human papilloma virus (HPV) type 16 infections of the genital tract are associated with the development of cervical cancer (CxCa) in women. HPV16-derived oncoproteins E6 and E7 are expressed constitutively in these lesions and might therefore be attractive candidates for T-cell-mediated adoptive immunotherapy. However, the low precursor frequency of HPV16E7-specific T cells in patients and healthy donors hampers routine isolation of these cells for adoptive transfer. To overcome this problem, we have isolated T cell receptor (TCR) genes from four different HPV16E7-specific healthy donor and patient-derived human cytotoxic T lymphocyte (CTL) clones. We examined whether genetic engineering of peripheral blood-derived CD8+ T cells in order to express HPV16E711-20-specific TCRs is feasible for adoptive transfer purposes. Reporter cells (Jurkat/MA) carrying a transgenic TCR were shown to bind relevant but not irrelevant tetramers. Moreover, these TCR-transgenic Jurkat/MA cells showed reactivity towards relevant target cells, indicating proper functional activity of the TCRs isolated from already available T cell clones. We next introduced an HPV16E711-20-specific TCR into blood-derived, CD8+ recipient T cells. Transgenic CTL clones stained positive for tetramers presenting the relevant HPV16E711-20 epitope and biological activity of the TCR in transduced CTL was confirmed by lytic activity and by interferon (IFN)-gamma secretion upon antigen-specific stimulation. Importantly, we show recognition of the endogenously processed and HLA-A2 presented HPV16E711-20 CTL epitope by A9-TCR-transgenic T cells. Collectively, our data indicate that HPV16E7 TCR gene transfer is feasible as an alternative strategy to generate human HPV16E7-specific T cells for the treatment of patients suffering from cervical cancer and other HPV16-induced malignancies.  相似文献   
95.
Mosaic ring 12p and total anomalous pulmonary venous return   总被引:1,自引:0,他引:1  
An infant born with total anomalous pulmonary venous return (TAPVR) was found to have an extra chromosome present as a small ring. Spectral karyotyping and FISH analysis identified the material as a duplication involving the short arm of chromosome 12. Previous cases describing a variety of cytogenetic abnormalities that have been associated with TAPVR are reviewed along with prior cases of duplication 12p with their associated findings. We believe ours is the first case to report the occurrence of mosaic ring 12p and its association with TAPVR.  相似文献   
96.
A large family with three children affected with the autosomal recessive disease of Cerebrotendinous Xanthomatosis (CTX) was studied for class I (HLA-A,B,C) and class II antigens (HLA-DR,D,SB), properdin factor B and glyoxalase. The extensive typing revealed an informative cross-over between HLA-B and Bf, indicating that Bf is located centromeric to the HLA-B locus and segregated in this family with HLA-D/DR. The parents in this family were first cousins and their parents were also first cousins. Three of their four haplotypes share B14, BfS, DR1, Dx and SB4 and may be identical by descent. The three affected children carried among them all four parental haplotypes, indicating that close linkage of the CTX locus to HLA is unlikely.  相似文献   
97.
Eighteen pediatric cancer patients and their families participatedin a longitudinal study to assess the effects of a camp experienceon daily activity and family interactions. Based on maternalreport, changes were found in the amount of time these childrenspent in social, physical, and self-engaged activities. Mothersand a sibling closest in age to the patient also noted changesin their own frequency of activities spent with the family andwith others. These changes were evident when comparing measuresobtained 2 weeks prior to and 2 weeks after camp. Many changeswere still present 1 month after attending camp. These datasupport the use of a camp experience as an intervention to facilitatea return to more normal, healthy functioning by pediatric cancerpatients and their families.  相似文献   
98.
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases.  相似文献   
99.
A screening assay for detecting CD8+ cell non-cytotoxic anti-HIV responses   总被引:1,自引:0,他引:1  
The rate of HIV-1 disease progression is influenced by several factors that include pathogen and host genetic variations and the quality of antiviral immune responses. The CD8+ cell non-cytotoxic antiviral response (CNAR) substantially suppresses HIV replication in CD4+ cells and is positively associated with an asymptomatic clinical state. Traditionally, the measurement of CNAR has required several culture procedures and costly reagents. Here we report the development and validation of a screening assay for detection of CNAR that accurately identifies individuals benefiting from this response. Use of the CNAR screening assay should facilitate the evaluation of this important immune parameter in studies of HIV pathogenesis, resistance to infection, and vaccine development.  相似文献   
100.
Diagnosis of gastrointestinal stromal tumors: A consensus approach   总被引:258,自引:0,他引:258  
As a result of major recent advances in understanding the biology of gastrointestinal stromal tumors (GISTs), specifically recognition of the central role of activating KIT mutations and associated KIT protein expression in these lesions, and the development of novel and effective therapy for GISTs using the receptor tyrosine kinase inhibitor STI-571, these tumors have become the focus of considerable attention by pathologists, clinicians, and patients. Stromal/mesenchymal tumors of the gastrointestinal tract have long been a source of confusion and controversy with regard to classification, line(s) of differentiation, and prognostication. Characterization of the KIT pathway and its phenotypic implications has helped to resolve some but not all of these issues. Given the now critical role of accurate and reproducible pathologic diagnosis in ensuring appropriate treatment for patients with GIST, the National Institutes of Health convened a GIST workshop in April 2001 with the goal of developing a consensus approach to diagnosis and morphologic prognostication. Key elements of the consensus, as described herein, are the defining role of KIT immunopositivity in diagnosis and a proposed scheme for estimating metastatic risk in these lesions, based on tumor size and mitotic count, recognizing that it is probably unwise to use the definitive term "benign" for any GIST, at least at the present time.  相似文献   
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