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Background: Celiac disease (CD) and immunosuppression are the two risk factors for gastrointestinal, as well as non-gastrointestinal, non-Hodgkin’s lymphomas (NHL). Recent large retrospective studies confirm that celiac disease significantly increases risk of developing small bowel lymphomas by 30 to 40 percent and other gut malignancies by 83-fold. Case Report: A 75-year-old man with a history of CD of two-year duration presented with pallor, fatigue, and 20-pound weight loss of three weeks duration. There was a vague non-tender mass in the right hypochondrium, and his stools tested positive for occult blood. The lab values were within normal range, except for hemoglobin of 11mg/dL, MCV 75, mildly elevated SGOT of 61 IU/L, and LDH of about 5000 IU/L. Work-up including computerized tomography (CT) scan, positron emission tomography (PET) scan, and colonoscopy were performed. Results: A CT scan of the abdomen showed extensive carcinomatosis, scattered lymphadenopathy, and small pleural effusions. PET scan results coincided with CT findings. Colonoscopy revealed a friable nodular mass in the hepatic flexure, histopathology of which confirmed a high-grade B-cell lymphoma. Flow cytometry following immunostaining was positive for CD10, CD19, CD20, CD45, CD79a, and Ki-67. FISH assay demonstrated t (14:18) translocation and bcl-2 rearrangement. The bone marrow biopsy showed evidence of disease. The patient was treated with rituximab, plus cyclophosphamide, Adriamycin, vincristine, and prednisone (CHOP-R), with intrathecal methotrexate prophylaxis. Currently, the patient remains in remission. Conclusion: This is the first case of aggressive Burkitt-like lymphoma (BLL) occurring in a patient with celiac disease in his eighth decade of life. It is possible that chronic inflammation, profound immunosuppression, and nutritional deficit could lead to development of high-grade B-cell lymphoproliferative disorders. Further molecular studies are warranted to the investigate the link between certain polymorphisms of human leukocyte antigens (HLA) in B-cell populations in the gut, and this might be useful to identify high-risk individuals in the population of patients with CD.  相似文献   
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We designed and validated a novel device for applying flexion-extension cycles to a rat knee in an in vivo model of anterior cruciate ligament reconstruction (ACL-R). Our device is intended to simulate rehabilitation motion and exercise post ACL-R to optimize physical rehabilitation treatments for the improved healing of tendon graft ligament reconstructions. The device was validated for repeatability of the knee kinematic motion by measuring the force versus angular rotation response from repeated trials using cadaver rats. The average maximum force required for rotating an ACL reconstructed rat knee through 100 degrees of flexion-extension was 0.4 N with 95% variability for all trials within ±0.1 N.  相似文献   
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K Jung  Q Wang  Y Kim  K Scheuer  Z Zhang  Q Shen  KO Chang  LJ Saif 《PloS one》2012,7(7):e41619
The lack of an animal model for human norovirus (HuNoV) has hindered the development of therapeutic strategies. This study demonstrated that a commonly used cholesterol-lowering statin medication, simvastatin, which increases HuNoV replication in an in vitro replicon system, also enhances HuNoV infectivity in the gnotobiotic (Gn) pig model. In contrast, oral treatment with interferon (IFN)-α reduces HuNoV infectivity. Young piglets, all with A or H1 histo-blood group antigens on enterocytes, were treated orally with 8 mg/kg/day of simvastatin; 5 days later, the pigs were inoculated orally with a GII.4 HuNoV (HS194/2009/US strain) and then treated with simvastatin for 5 more days. Simvastatin induced significantly earlier onset and longer duration of HuNoV fecal shedding in treated pigs, frequently with higher fecal viral titers. Simvastatin impaired poly (I:C)-induced IFN-α expression in macrophages or dendritic cells, possibly due to lowered toll-like receptor (TLR) 3 expression; however, the mechanisms were not related to interferon regulatory factor 3 or nuclear factor kappa B signaling pathway. Thus, the enhanced, earlier infectivity of HuNoV in simvastatin-treated pigs coincided with the inhibitory effect of simvastatin on innate immunity. In contrast to the increased HuNoV shedding that simvastatin induced, viral shedding during the treatment period was reduced or curtailed in the HuNoV-inoculated pigs pre-treated/treated with human IFN-α. Our findings are the first to indicate that IFN-α has potential as antiviral therapy against HuNoV. Based on these intriguing and novel findings using the Gn pig model, we confirmed that HuNoV infectivity is altered by treatment with simvastatin or IFN-α. Collectively, these findings indicate that Gn pigs are a useful model to test immunomodulators or efficacy of antivirals against HuNoV.  相似文献   
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ABSTRACT: BACKGROUND: Stroke is a potential complication of acute coronary syndrome (ACS). The aim of this study was to identify the prevalence, risk factors predisposing to stroke, in-hospital and 1-year mortality among patients presenting with ACS in the Middle East. METHODS: For a period of 9 months in 2008 to 2009, 7,930 consecutive ACS patients were enrolled from 65 hospitals in 6 Middle East countries. RESULTS: The prevalence of in-hospital stroke following ACS was 0.70%. Most cases were ST segment elevation MI-related (STEMI) and ischemic stroke in nature. Patients with in-hospital stroke were 5 years older than patients without stroke and were more likely to have hypertension (66% vs. 47.6%, P = 0.001). There were no differences between the two groups in regards to gender, other cardiovascular risk factors, or prior cardiovascular disease. Patients with stroke were more likely to present with atypical symptoms, advanced Killip class and less likely to be treated with evidence-based therapies. Independent predictors of stroke were hypertension, advanced killip class, ACS type --STEMI and cardiogenic shock. Stroke was associated with increased risk of in-hospital (39.3% vs. 4.3%) and one-year mortality (52% vs. 12.3%). CONCLUSION: There is low incidence of in-hospital stroke in Middle-Eastern patients presenting with ACS but with very high in-hospital and one-year mortality rates. Stroke patients were less likely to be appropriately treated with evidence-based therapy. Future work should be focused on reducing the risk and improving the outcome of this devastating complication.  相似文献   
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We sequenced and analyzed the full-length genomes of four coronaviruses (CoVs), each from a distinct wild-ruminant species in Ohio: sambar deer (Cervus unicolor), a waterbuck (Kobus ellipsiprymnus), a sable antelope (Hippotragus niger), and a white-tailed deer (Odocoileus virginianus). The fecal samples from the sambar deer, the waterbuck, and the white-tailed deer were collected during winter dysentery outbreaks and sporadic diarrhea cases in 1993 and 1994 (H. Tsunemitsu, Z. R. el-Kanawati, D. R. Smith, H. H. Reed, and L. J. Saif, J. Clin. Microbiol. 33:3264-3269, 1995). A fecal sample from a sable antelope was collected in 2003 from an Ohio wild-animal habitat during the same outbreak when a bovine-like CoV from a giraffe (GiCoV) was isolated (M. Hasoksuz, K. Alekseev, A. Vlasova, X. Zhang, D. Spiro, R. Halpin, S. Wang, E. Ghedin, and L. J. Saif, J. Virol. 81:4981-4990, 2007). For two of the CoVs (sambar deer and waterbuck), complete genomes from both the cell culture-adapted and gnotobiotic-calf-passaged strains were also sequenced and analyzed. Phylogenetically, wild-ruminant CoVs belong to group 2a CoVs, with the closest relatedness to recent bovine CoV (BCoV) strains. High nucleotide identities (99.4 to 99.6%) among the wild-ruminant strains and recent BCoV strains (BCoV-LUN and BCoV-ENT, isolated in 1998) further confirm the close relatedness. Comparative genetic analysis of CoVs of captive wild ruminants with BCoV strains suggests that no specific genomic markers are present that allow discrimination between the bovine strains and bovine-like CoVs from captive wild ruminants; furthermore, no specific genetic markers were identified that defined cell cultured or calf-passaged strains or the host origin of strains. The results of this study confirm prior reports of biologic and antigenic similarities between bovine and wild-ruminant CoVs and suggest that cattle may be reservoirs for CoVs that infect captive wild ruminants or vice versa and that these CoVs may represent host range variants of an ancestral CoV.  相似文献   
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We previously characterized the pathogenesis of two host-specific bovine enteric caliciviruses (BEC), the GIII.2 norovirus (NoV) strain CV186-OH and the phylogenetically unassigned NB strain, in gnotobiotic (Gn) calves. In this study we evaluated the Gn calf as an alternative animal model to study the pathogenesis and host immune responses to the human norovirus (HuNoV) strain GII.4-HS66. The HuNoV HS66 strain caused diarrhea (five/five calves) and intestinal lesions (one/two calves tested) in the proximal small intestine (duodenum and jejunum) of Gn calves, with lesions similar to, but less severe than, those described for the Newbury agent 2 (NA-2) and NB BEC. Viral capsid antigen was also detected in the jejunum of the proximal small intestine of one of two calves tested by immunohistochemistry. All inoculated calves shed virus in feces (five/five calves), and one/five had viremia. Antibodies and cytokine (proinflammatory, tumor necrosis factor alpha [TNF-α]; Th1, interleukin-12 [IL-12] and gamma interferon [IFN-γ]; Th2, IL-4; Th2/T-regulatory, IL-10) profiles were determined in serum, feces, and intestinal contents (IC) of the HuNoV-HS66-inoculated calves (n = 5) and controls (n = 4) by enzyme-linked immunosorbent assay in the acute (postinoculation day 3 [PID 3]) and convalescent (PID 28) stages of infection. The HuNoV-HS66-specific antibody and cytokine-secreting cells (CSCs) were quantitated by ELISPOT in mononuclear cells of local and systemic tissues at PID 28. Sixty-seven percent of the HuNoV-HS66-inoculated calves seroconverted, and 100% coproconverted with immunoglobulin A (IgA) and/or IgG antibodies to HuNoV-HS66, at low titers. The highest numbers of antibody-secreting cells (ASC), both IgA and IgG, were detected locally in intestine, but systemic IgA and IgG ASC responses also occurred in the HuNoV-HS66-inoculated calves. In serum, HuNoV-HS66 induced higher peaks of TNF-α and IFN-γ at PIDs 2, 7, and 10; of IL-4 and IL-10 at PID 4; and of IL-12 at PIDs 7 and 10, compared to controls. In feces, cytokines increased earlier (PID 1) than in serum and TNF-α and IL-10 were elevated acutely in the IC of the HS66-inoculated calves. Compared to controls, at PID 28 higher numbers of IFN-γ and TNF-α CSCs were detected in mesenteric lymph nodes (MLN) or spleen and Th2 (IL-4) CSCs were elevated in intestine; IL-10 CSCs were highest in spleen. Our study provides new data confirming HuNoV-HS66 replication and enteropathogenicity in Gn calves and reveals important and comprehensive aspects of the host's local (intestine and MLN) and systemic (spleen and blood) immune responses to HuNoV-HS66.  相似文献   
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In the Kingdom of Saudi Arabia (KSA), breast cancer constitutes 18% of all cancers in Saudi women. Whilst locally advanced breast cancer disease is unusual in Western countries, it constitutes more than 40% of all non-metastatic breast cancer in KSA. The relative frequency of locally advanced disease among our breast cancer population and the lack of a uniform consensus in the literature about its optimal management have prompted this retrospective analysis of the medical records of patients with Stage III breast cancer patients seen at King Faisal Specialist Hospital and Research Center between 1981 and 1991. In all, 315 patients were identified. Their median age ±SD was 46±11.6 years which is distinctly different from the 60–65 years median age in industrial Western nations. Most patients were younger than 50 years (64%) and premenopausal (62%). Patients were approximately equally divided between Stage III A and Stage III B Patients received multimodality treatment, including surgery., adjuvant chemotherapy, tamoxifen, and adjuvant radiotherapy. Sixty-one patients were excluded from survival analysis as they were considered lost to follow-up. Of the remaining 254 patients, 73 (29%) were alive and disease free, and 18 patients (7%) were alive but, with evidence of the disease. The remaining 163 (64%) had died from breast cancer or its related complications. Their median overall survival (OS) was 54 months, (95%, Cl, 27 to 121 months) and the median progression-free survival (PFS) was 28.8 months (95% Cl, 14.2 to 113 months). Cox proportional hazard, model identified Stage III B and the number of positive axillary lymph nodes as poor predictors of OS and PFS. Radiotherapy was the only adjuvant modality that affected survival favourably. The prognosis of patients with Stage III disease remains poor despite the use of a multimodality approach. The overall young age of our patients may have contributed to the poor outcome. Moreover, the adverse effect of Stage III B disease (as compared with Stage III A) and axillary nodal status was evident. Whilst the favourable effect of radiotherapy on survival was demonstrated, the lack of independent efficacy of other modalities (adjuvant chemotherapy and tamoxifen) or the apparent deleterious effect of neoadjuvant chemotherapy should be addressed with discretion in such retrospective analysis. Optimal management of patients with locally advanced breast cancer disease should be appraised in well designed, prospective, randomised studies.  相似文献   
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