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1.
BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India.  相似文献   
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Gastrointestinal manifestations of dengue fever are mainly in the form of bleeding or liver function abnormalities. Dengue fever presenting as acute colitis-like picture is not reported to date. We report a 50-year-old man with dengue fever presenting with lower gastrointestinal bleeding and colonoscopic features of acute inflammatory colitis.  相似文献   
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BK virus nephropathy (BKVN) is now recognized as a major cause of renal allograft loss. Recent reports suggest that retransplantation in patients with graft loss due to BKVN is safe after return to dialysis. Since early transplantation is associated with improved outcomes, it would be advantageous if this procedure could be performed prior to ultimate graft loss. However, little data are available regarding the safety of this approach during active viremia. In this report, we describe successful preemptive retransplantation with simultaneous allograft nephrectomy in two patients with active BKVN and viremia at the time of surgery. With 21- and 12-month follow-up, respectively, both patients have stable allograft function and no evidence for active viral replication. We conclude that preemptive retransplantation can be considered in patients with failing allografts due to BKVN.  相似文献   
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Neurofibromas in the hand are uncommon and constitute less than 5% of all hand tumours. Accurate diagnosis and appropriate management are important because malignant transformation has been reported, especially in Von Recklinghausen’s neurofibromatosis. We report a case of a large neurofibroma in the right hand of an 18-year-old girl of Afro-Caribbean origin. She was symptomatic with complaints of pain and weakness of grip. General examination revealed multiple café-au-lait spots on the trunk and one nodular swelling in the forearm. The swelling was excised through a palmar approach and histology proved it to be a neurofibroma. The case is being reported for its rarity and it emphasizes the importance of general examination. Histopathological examination is vital in excluding malignant transformation.  相似文献   
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Gelrite, a heteropolysaccharide that forms a gel in the presence of cations, was tested in humans for its efficacy as an ophthalmic vehicle by a nonivasive fluorometric technique. Fluorescein was used as the tracer, and its concentration in the anterior chamber was used as the principal measure of bioavailability. The gel afforded a twofold increase in penetration of fluorescein compared with an isotonic buffer solution; this increase is slightly more than can be obtained with simple viscous vehicles. The increase in penetration caused by Gelrite was confirmed by measurements of the contact time of fluorescein in the tear film with the cornea. Earlier experiments with scintigraphy suggested a considerably greater contact time of fluorescein with the cornea when Gelrite was used. However, this increased contact time may be because the technique also measures radioactive tracer that had dried out on the lid margins. Accordingly, significant quantities of fluorescein could be eluted from the lids after the penetration experiments were completed.  相似文献   
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Mycobacterium tuberculosis, the etiological agent of tuberculosis, has lost many coding and noncoding regions in its genome during the course of evolution. We performed region-of-difference (RD) analysis using PCR-based genotyping of 131 M. tuberculosis clinical isolates obtained from four different countries, namely, India, Peru, Libya, and Angola. Our studies revealed that RD patterns are often distinct for strains circulating in specific geographical regions and can be used to trace the descent and spread of an isolate from its original reservoir. We describe our findings, which show that no single isolate from the four countries (n = 131) had all the 15 RDs either deleted or retained. Tuberculosis-specific deletion 1 (TbD1) was found to be conserved in 23% of the Indian isolates, indicating their possible ancient origin. RD9 was the most conserved region, RD11 was predominantly deleted, and RD6 was the most variable among the isolates in our collection irrespective of their geographic region. In contrast to earlier reports, our results demonstrate that the deletion of RD1 does not correlate with a decrease in the virulence potential of M. tuberculosis, as Indian isolates (n = 30) examined by us were from diseased individuals and yet had lost the RD1 region. Our results further illustrated that the intactness of the RD5 region may be associated with increased virulence of the organism. This study highlights that the RDs in M. tuberculosis genomes are geographically distributed and specific and may possibly be associated with virulence spectrum.  相似文献   
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Febrile-range hyperthermia (FRH) improves survival in experimental infections by accelerating pathogen clearance, but may also increase collateral tissue injury. We hypothesized that FRH would worsen the outcome of inflammation stimulated by a non-replicating agonist and tested this hypothesis in a murine model of pulmonary oxygen toxicity. Using a conscious, temperature-controlled mouse model, we showed that maintaining a core temperature at FRH (39 degrees C to 40 degrees C) rather than at euthermic levels (36.5 degrees C to 37 degrees C) during hyperoxia exposure accelerated lethal pulmonary vascular endothelial injury, reduced the inspired oxygen threshold for lethality, induced expression of granulocyte-colony stimulating factor, and expanded the circulating neutrophil pool. In these same mice, FRH augmented pulmonary expression of the ELR(+) CXC chemokines, KC and LPS-induced CXC chemokine, enhanced recruitment of neutrophils, and changed the histological pattern of lung injury to a neutrophilic interstitial pneumonitis. Immunoblockade of CXC receptor-2 abrogated neutrophil recruitment, reduced pulmonary vascular injury, and delayed death. These combined data demonstrate that FRH may enlist distinct mediators and effector cells to profoundly shift the host response to a defined injurious stimulus, in part by augmenting delivery of neutrophils to sites of inflammation, such as may occur in infections. In certain conditions, such as in the hyperoxic lung, this process may be deleterious.  相似文献   
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