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71.
Eradication of established tumors by CD8+ T cell adoptive immunotherapy   总被引:14,自引:0,他引:14  
We generated the DUC18 T cell receptor transgenic mouse expressing an H-2Kd -restricted transgenic T cell receptor specific for the syngeneic CMS5 fibrosarcoma rejection antigen mutated ERK2(136-144). DUC18 mice were capable of specifically eliminating lethal CMS5 tumor challenges, and transfer of DUC18 splenocytes to naive nontransgenic recipients conferred protection from subsequent and established CMS5 tumor burdens. Eradication of established tumor burdens by adoptive transfer of DUC18 splenocytes was dose and time dependent. Transferred tumor-specific T cells remained functional in vivo and capable of rejecting small tumors even in the presence of large, established tumor burdens. These findings highlight the kinetic battle between tumor growth and the production of a tumor-specific response and have critical implications for effective adoptive immunotherapy.  相似文献   
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Four families are described with a t(13q14q) segregating. Two of them were identified through index cases with Down's syndrome; their karotypes revealed the unusual 46,XY, -13, -14, +t(13q14q), +21. The other two families were identified through a chromosomal study of parents with repeated spontaneous abortions. Analysis of data on 3 of these 4 families and on 7 other from the published reports showed no evidence of increased fetal wastage among 13/14 carriers. However, the risk of producing offspring with various types of aneuploidy may be greater among carriers than among persons with a normal chromosome pattern. Qualitative and quantitative differences in D/D translocations may account for the observed variation in clinical findings. These differences add to the problem of determining genetic risks from an analysis of grouped data.  相似文献   
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B?rjeson-Forssman-Lehmann syndrome: further delineation in five cases   总被引:1,自引:0,他引:1  
We have studied five males with B?rjeson-Forssman-Lehmann syndrome (BFLS) from two unrelated families. They had a characteristic facial appearance with prominent supraorbital ridges, deep-set eyes, ptosis, and large ears, as well as obesity, severe mental retardation, hypotonia, and hypogonadism. Ophthalmologic, EEG, and skeletal abnormalities were also present. The findings in several presumed or possible heterozygous women were evaluated and suggested a wide range of phenotypic effects varying between apparent normality to mild or moderately evident BFLS manifestations. The observed pattern of occurrence of the BFLS in our two families provides strong support for X-linked inheritance. In clinically normal female relatives at risk for being carriers of BFLS, we have been unsuccessful in identifying a reliable screening test. The condition in our and previously reported patients was contrasted with other malformation syndromes and our findings support the conclusion that BFLS is a distinct and clinically identifiable disorder.  相似文献   
76.
Blood compatibility of surfaces modified by plasma polymerization   总被引:3,自引:0,他引:3  
Tubular blood-contacting polymeric materials were modified by plasma polymerization and evaluated in the baboon with respect to their capacity to induce both acute and chronic arterial thrombosis. Polymer surface composition was determined by electron spectroscopy for chemical analysis. Steady-state arterial thromboembolism was initiated by introducing tubular segments into chronic arteriovenous shunts. Rates of platelet destruction induced by the test materials were calculated from 111In-platelet survival measurements. Nine plasma polymers based on tetrafluoroethylene, hexafluoroethane, hexafluoroethane/H2, and methane, when deposited on silicone rubber, consumed platelets at rates ranging from 1.1-5.6 x 10(8) platelets/cm2-day. Since these values were near the lower detection limit for this test system, the plasma polymers were considered relatively nonthrombogenic. Acute thrombus formation was initiated by inserting expanded Teflon (Gore-Tex PTFE) vascular grafts into the shunt system. 111In-platelet deposition was measured by scintillation camera imaging over a 1-h exposure period. Standard PTFE grafts (10 cm x 4 mm i.d.) accumulated approximately 1 x 10(10) platelets over this interval. While modification of PTFE grafts with a plasma polymer based on hexafluoroethane/H2 did not alter graft surface morphology, platelet deposition was reduced by 87% as compared to the controls (p less than 0.001). We conclude that both the surface chemistry and texture of prosthetic materials influence thrombogenesis. The method of plasma polymerization may be useful for assessing the importance of these variables independently and, perhaps, for minimizing certain adverse blood-material interactions.  相似文献   
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Hypersensitivity to the fungal antigens of Aspergillus fumigatus may result in a spectrum of immune injury collectively known as allergic bronchopulmonary aspergillosis (ABPA). This report describes a 14-yr-old boy who presented clinical findings consistent with ABPA,including a history of asthma, blood eosinophilia, serum precipitins, and IgE antibodies to Aspergillus fumigatus. Sputum Aspergillus, pulmonary infiltrates, and dual types I and III skin reactions to Aspergillus fumigatus were observed also. Pathology of the resected right upper lobe revealed severe bronchial destruction with the findings of bronchocentric granulomatosis. Noninvasive septate fungal hyphae compatible with Aspergillus were identified. Cultures from sputum and surgical specimens grew Aspergillus and Mycobacterium intracellulare avium. The PPD-B (purified protein derivative-Batty) intradermal skin test produced a 6 mm induration (PPD-S was negative). The patient's condition has been well controlled with prednisone and several antituberculous drugs. In addition, inflammatory and immunologic parameters have begun to return to normal. The relationship between ABa and the atypical mycobacterial infection is not clear. The association of ABPA with the severe bronchial destruction seen in bronchocentric granulomatosis is emphasized to alert physicans to this serious sequelae of ABa seen in the asthmatic.  相似文献   
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Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
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