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51.
Macrophage migration inhibitory factor (MIF) is a key proinflammatory mediator, which plays a pivotal role in inflammatory and immune diseases. We attempted to clarify associations of the functional polymorphisms of the MIF gene promoter with the development of chronic gastritis. The study was performed with 290 stocked DNAs from subjects with no evidence of gastric malignancy. We employed the PCR-SSCP method to detect gene polymorphisms. The severity of histological chronic gastritis in antral biopsy specimens was classified according to the updated Sydney system. Both the 7/7-CATT repeat at position -794 and the -173 C/C genotypes were significantly associated with a risk of developing severe gastric mucosal atrophy (OR, 9.69; 95% CI, 1.29-72.5; and OR, 4.60; 95% CI, 1.05-20.2, respectively). In subjects younger than 60 years old, the number of 7-CATT alleles was significantly correlated with both the activity and inflammation scores (p=0.0079 and 0.0080, respectively). Our results suggested that functional promoter polymorphisms of the MIF gene might be associated with the severity of gastric mucosal inflammation in younger subjects and with the subsequent development of mucosal atrophy.  相似文献   
52.
Spinal deformity is an important clinical manifestation after surgery for spinal cord tumors. One-third of patients who receive laminectomies and irradiation of the spinal column develop scoliosis, kyphosis, or kyphoscoliosis. Recent reports indicate good results after scoliosis surgery using segmental pedicle screws and a navigation system, but these reported studies have not included surgery for post-laminectomy kyphosis. Hooks and wires are ineffective in such patients who undergo laminectomy, and there are also high perioperative risks with insertion of pedicle screws because landmarks have been lost. Here, we report on the 5-year follow-up of a 13-year-old male patient with post-laminectomy and post-irradiation thoracic kyphoscoliosis after surgical treatment of spinal astrocytoma. Posterior segmental pedicle screw fixation was performed safely using a computer-assisted technique. The authors present the first case report for treatment of this condition using a navigation system.  相似文献   
53.
Deficiency of zinc, which modulates glutamate release, might increase ischemic vulnerability of the brain. We examined effects of dietary zinc deficiency for 2 weeks on ischemic vulnerability in several brain regions using dynamic positron autoradiography technique and [18F]2-fluoro-2-deoxy-d-glucose with rat brain slices. In the normal diet group, the cerebral glucose metabolic rate (CMRglc) was not significantly different from that of the ischemia-unloaded control even after the loading of ischemia for 45 min. However, in the zinc-deficient diet group, CMRglc was significantly lower than that of the ischemia-unloaded control after loading of ischemia for 45 min. With treatment of MK-801 (NMDA receptor antagonist) from the start of ischemia loading, CMRglc was not significantly different from that of the ischemia-unloaded control. These findings, obtained for all analyzed brain regions, suggest that dietary zinc deficiency increased ischemic vulnerability in the brain, and that glutamate might contribute to this effect through activation of the NMDA receptor.  相似文献   
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An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.  相似文献   
56.
We developed an immunochromatographic assay kit that uses fluorescent silica nanoparticles bound to anti-Acanthamoeba antibodies (fluorescent immunochromatographic assay [FICGA]) and evaluated its efficacy for the detection of Acanthamoeba and diagnosis of Acanthamoeba keratitis (AK). The sensitivity of the FICGA kit was evaluated using samples of Acanthamoeba trophozoites and cysts diluted to various concentrations. A conventional immunochromatographic assay kit with latex labels (LICGA) was also evaluated to determine its sensitivity in detecting Acanthamoeba trophozoites. To check for cross-reactivity, the FICGA was performed by using samples of other common causative pathogens of infectious keratitis, such as Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans. Corneal scrapings from patients with suspected AK were tested with the FICGA kit to detect the presence of Acanthamoeba, and the results were compared with those of real-time PCR. The FICGA kit detected organisms at concentrations as low as 5 trophozoites or 40 cysts per sample. There were no cross-reactivities with other pathogens. The FICGA was approximately 20 times more sensitive than the LICGA for the detection of Acanthamoeba trophozoites. The FICGA kit yielded positive results for all 10 patients, which corresponded well with the real-time PCR results. The FICGA kit demonstrated high sensitivity for the detection of Acanthamoeba and may be useful for the diagnosis of AK.  相似文献   
57.
Non‐O157 Shiga toxin‐producing Escherichia coli (STEC) strains are increasingly recognized as foodborne pathogens that trigger hemolytic uremic syndrome (HUS). The detection and isolation of these strains is important, but distinguishing their bacteriological profiles is difficult. A 2‐year‐old girl developed HUS with mild renal involvement 22 days after consuming barbecued meat. Clinical and laboratory findings gradually improved without specific treatment. Because neither enterohemorrhagic E. coli (EHEC) nor Shiga toxins were detected in stool cultures in a clinical laboratory and the patient tested negative for circulating antibodies to O157 lipopolysaccharide, the case was initially diagnosed as probable atypical HUS. Subsequent serodiagnostic microagglutination assay and polymerase chain reaction‐based molecular testing, however, indicated the presence of the EHEC O121:H19 strain with stx2. Thus, to correctly diagnose and treat HUS, a system for detecting non‐O157 STEC in a clinical setting is urgently needed.  相似文献   
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Two cases of carcinoma arising from the urinary bladder diverticulum were found at autopsy. Both patients had hematuria as a chief complaint and were found to have a tumor mass in the bladder on cystoscopic examination. However, owing to various difficulties the tumors could not be diagnosed before death. Autopsy revealed that the tumors in both cases had arisen within diverticula and had grown into the orifice of the diverticula giving the appearance of ordinary bladder tumors. Histological examination showed that in Case 1, two carcinomas, a keratinizing squamous cell carcinoma and a transitional cell carcinoma, had developed separately in a diverticulum. This may be the first case report of two cancers in a bladder diverticulum. There were no metastases in this case. Case 2 had an undifferentiated carcinoma with metastases to many organs including the lung, liver, and lymph nodes.  相似文献   
60.
Invasion of antigens through the mucosal surface can be prevented by the common mucosal immune system, including Peyer's patches (PPs) and nasopharyngeal-associated lymphoreticular tissue (NALT). The adenoids (nasopharyngeal tonsils) comprise one of the NALTs and constitute the major part of Waldeyer's lymphoid ring in humans. However, the role of the lymphoepithelium, including M cells and dendritic cells (DCs), in the adenoids is unknown compared with the epithelium of PPs. NALTs also have unique functions such as the barrier of epithelial cells and uptake of antigens by M cells and DCs, and may play a crucial role in airway mucosal immune responses. The lymphoepithelium of adenoids has well-developed tight junctions that play an important role in the barrier function, the same as nasal epithelium but not palatine tonsillar epithelium. Tight junction molecules are expressed in both M cells and DCs as well as epithelial cells, and various antigens may be sampled, transported, and released to lymphocytes through the cells while they maintain the integrity of the epithelial barrier. This review summarizes the recent progress in our understanding of how M cells and DCs control the epithelial barrier in the adenoids.  相似文献   
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