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Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection.  相似文献   
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Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.  相似文献   
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Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   
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Herpesvirus, cytomegalovirus, human sperm and assisted fertilization   总被引:6,自引:0,他引:6  
BACKGROUND: The effect of viral particles on the motility of human sperm and the relationship between sperm and virus are of importance particularly in assisted fertilization. METHODS: We incubated ejaculated sperm with or without seminal fluid with either herpes simplex virus type 2 (HSV2) or human cytomegalovirus (HCMV). For each experiment, 5 x 10(5) sperm were incubated with a viral load of between 10(4) and 10(6) plaque-forming units. RESULTS: We detected no apparent variations in the percentage of motile forms when sperm were incubated with either HSV2 or HCMV. Using a computer-aided semen analysis system, a slight difference was reported in the percentage of motile forms when seminal fluid-free sperm were incubated with HSV2 (57.18 versus 64.43 in the control). Although the mean amplitude of lateral head displacement and the curvilinear velocity were significantly higher in infected sperm, the difference in straight line velocity was not statistically significantly different. Few viral particles (HSV2 or HCMV) adhered to the sperm membrane in the presence of seminal fluid. However, more particles stuck when in the absence of seminal fluid, particularly with HSV2 (8% of sperm sections for HSV2; 4% for HCMV). CONCLUSIONS: The relationship between sperm and viruses depends on the type of virus present as well as the presence or absence of seminal fluid. Motility is not a good enough criterion on which to prove the presence of viral elements, either in the medium or on the sperm.  相似文献   
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BackgroundIschemia-driven islet isolation procedure is one of the limiting causes of pancreatic islet transplantation. Ischemia-reperfusion process is associated with endothelium dysfunction and the release of pro-senescent microvesicles. We investigated whether pro-senescent endothelial microvesicles prompt islet senescence and dysfunction in vitro.Material and methodsPancreatic islets were isolated from male young rats. Replicative endothelial senescence was induced by serial passaging of primary porcine coronary artery endothelial cells, and microvesicles were isolated either from young passage 1 (P1) or senescent passage 3 (P3) endothelial cells. Islet viability was assessed by fluorescence microscopy, apoptosis by flow cytometry, and Western blot. Function was assessed by insulin secretion and islet senescence markers p53, p21, and p16 by Western blot. Microvesicles were stained by the PKH26 lipid fluorescent probe and their islet integration assessed by microscopy and flow cytometry.ResultsRegardless of the passage, half microvesicles were integrated in target islets after 24 hours incubation. Insulin secretion significantly decreased after treatment by senescent microvesicles (P3: 1.7 ± 0.2 vs untreated islet: 2.7 ± 0.2, P < .05) without altering the islet viability (89.47% ± 1.69 vs 93.15% ± 0.97) and with no significant apoptosis. Senescent microvesicles significantly doubled the expression of p53, p21, and p16 (P < .05), whereas young microvesicles had no significant effect.ConclusionPro-senescent endothelial microvesicles specifically accelerate the senescence of islets and alter their function. These data suggest that islet isolation contributes to endothelial driven islet senescence.  相似文献   
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Background:Randomizing patients to bladder preservation or radical cystectomy (RC) for the treatment of bladder cancer has not been practical, due to patient and physician preferences. Therefore, continually comparing the 2 treatment modalities is needed, in order to make the proper choice for each patient.Patients and methods:The records of T1–4N0M0 bladder cancer patients, who presented to the South Egypt Cancer Institute between 2007 and 2017 and were treated by either bladder preservation or RC were reviewed.Results:Out of the 166 included patients, 81 (48.8%) patients were treated by bladder preservation and 85 (51.2%) patients had RC. For the patients treated by bladder preservation and the patients treated by RC, the 5-year overall survival (OS) was 56% and 60% (p = 0.67), the 5-year local recurrence-free survival was 69% and 73% (p = 0.69), and the 5-year disease-free survival was 45% and 53% (p = 0.16), respectively. After propensity matching analysis, the mean 5-year OS was 58% for the bladder preservation patients and 61% for the RC patients (p = 0.51). It is notable that among the bladder preservation group, 8 patients (10%) had squamous cell carcinoma (SCC) pathology and refused RC. Their OS was 56% compared to 53% for the SCC patients treated by RC (p = 0.6).Conclusion:Bladder preservation is a safe alternative to cystectomy in transitional cell carcinoma stages T1–4aN0M0, and its use in SCC bladder cancer should be further studied, as it could be feasible to spare them from initial cystectomy.  相似文献   
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