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91.
Inflammation associated with nerve injury produces a number of pathogenic chemical mediators of which prostanoids are a potent component. Cyclooxygenases (Cox-1 and Cox-2) are the enzymes responsible for prostanoid production. We have investigated Cox-2 immunoreactivity (Cox-2-IR) and glial activation in human injured (n = 16) and uninjured (n = 8) nerves and in the chronic constriction injury (CCI) model of nerve injury in the rat, using immunohistological and autoradiographic methods. Tissues were immunostained with antibodies to Cox-2, CD-68 (human macrophage marker), OX42 (rat microglial marker), or incubated with tritiated PK11195 (marker of glial activation), prior to image analysis. In human nerves, Cox-2-IR was detected in cells with morphology and distribution similar to macrophages/microglia - these were increased significantly in human nerve proximal to injury (p < 0.002), reaching a peak at 4-6 weeks after injury. In the rat CCI model, at 40 days after injury, microglia-like cells with Cox-2-IR were increased significantly in the injured nerve (p < 0.004) and ipsilateral dorsal spinal cord (p < 0.008). PK11195-binding results were similar for Cox-2-IR in chronic injured human nerve and rat tissues. These findings suggest that Cox-2-immunoreactive cells could play a role in processes associated with Wallerian degeneration, nerve regeneration, and the development of persistent pain. Selection of patients 4-6 weeks after nerve injury would be more likely to show any efficacy of Cox-2 inhibitors.  相似文献   
92.
A recent large multi-centre study convincingly confirmed previous observations that the SYT-SSX1 fusion type, compared to SYT-SSX2, of synovial sarcoma is associated with a worse clinical outcome. Apart from the clinical impact, this fact also suggests (1) that the SYT-SSX fusion gene may influence molecular mechanisms involved in tumour growth and progression; and (2) that the SYT-SSX1 fusion type has a stronger influence on these mechanisms than SYT-SSX2. The nature of the underlying mechanisms is, however, still unknown. In this study we made use of the SYT-SSX1 vs SYT-SSX2 concept to investigate whether major, tumour relevant, and growth regulatory proteins (e.g. cyclins and cyclin-dependent kinases) may be involved. Using Western blotting analysis on 74 fresh, fusion variant-typed, tumour samples from localized synovial sarcoma, we found a significant correlation between SYT-SSX1 and high expression of cyclin A (P=0.003) and D1 (P=0.025). Our data suggest that SYT-SSX may influence the cell cycle machinery, and that the more aggressive phenotype of the SYT-SSX1 variant is due to an accelerated tumour cell proliferation.  相似文献   
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Notwithstanding the deficiencies in reporting, an attempt is made in the present study to provide some useful information on the importance of the communicable diseases in the world over the decade 1957-58 to 1967-68. In this period health authorities in the developing countries almost invariably reported communicable diseases as their main public health problems, whereas, in the developed countries, the only communicable diseases still considered as public health problems were tuberculosis, venereal diseases, and hepatitis. In the developing countries nearly half of the principal causes of death were communicable diseases, and in both the developing and developed countries respiratory infections ranked high on the list. Deaths from tuberculosis have come down markedly in the developed countries and to a lesser degree in the developing countries. Infectious diseases of childhood are no longer a problem in the developed countries but are still important in the developing countries. The communicable diseases of importance to the developing countries may be divided into two groups—those requiring long-term development for their solution (e.g., dysentery, typhoid fever, parasitic diseases, and respiratory infections) and those that would respond rapidly to control by such methods as immunization.  相似文献   
96.
Diabetes incurs heavy personal and health system costs. Self-management is required if complications are to be avoided. Adolescents face particular challenges as they learn to take responsibility for their diabetes. A systematic review of educational and psychosocial programmes for adolescents with diabetes was undertaken. This aimed to: identify and categorise the types of programmes that have been evaluated; assess the cost-effectiveness of interventions; identify areas where further research is required. Sixty-two papers were identified and subjected to a narrative review. Generic programmes focus on knowledge/skills, psychosocial issues, and behaviour/self-management. They result in modest improvements across a range of outcomes but improvements are often not sustained, suggesting a need for continuous support, possibly integrated into normal care. In-hospital education at diagnosis confers few advantages over home treatment. The greatest returns may be obtained by targeting poorly controlled individuals. Few studies addressed resourcing issues and robust cost-effectiveness appraisals are required to identify interventions that generate the greatest returns on expenditure.  相似文献   
97.
Cannabinoid receptor 2 (CB2) agonists provide the potential for treating chronic pain states without CNS effects associated with CB1 receptor activation. Animal models suggest that they act mainly via non-neuronal cells, possibly inhibition of inflammatory cells in the periphery or CNS, or via release of beta-endorphin; however, the clinical relevance and mechanism of analgesic action is uncertain. Here, we demonstrate colocalisation of CB2 with CB1 and the capsaicin receptor TRPV1 in human dorsal root ganglion (DRG) sensory neurons and increased levels of CB2 receptors in human peripheral nerves after injury, particularly painful neuromas. In primary cultures of human DRG neurons, selective CB2 agonists blocked activation of inward cation currents and elevation of cytoplasmic Ca2+ in response to capsaicin. These inhibitory effects were reversed by GW818646X a CB2 antagonist, and 8-bromo cAMP, but not by SR141716 a CB1 antagonist, or naloxone. Thus CB2 receptor agonists functionally inhibited nociceptive signalling in human primary sensory neurons via a mechanism shared with opioids, of adenylyl cyclase inhibition, but not via mu-opioid receptors. We conclude that CB2 agonists deserve imminent clinical trials for nociceptive, inflammatory and neuropathic chronic pain, in which capsaicin or heat-activated responses via TRPV1 may provide a clinical marker.  相似文献   
98.
Increased mast cells in the irritable bowel syndrome   总被引:30,自引:0,他引:30  
Mast cells (MC) release potent mediators which alter enteric nerve and smooth muscle function and may play a role in the pathogenesis of the irritable bowel syndrome (IBS). The aim of this study was to determine if MC were increased in the colon of IBS patients compared to controls. Biopsy specimens were obtained from the caecum, ascending colon, descending colon and rectum of 28 patients: 14 IBS (Rome criteria); seven normal; and seven inflammatory controls. Tissue was stained immunohistochemically using a monoclonal mouse antibody for human mast cell tryptase (AA1). Tissue area occupied by tryptase-positive MC (volume density of mast cells) was quantified by image analysis. The number of plasma cells, lymphocytes, eosinophils, neutrophils and macrophages were each graded semiquantitatively (0-4) in haematoxylin and eosin stained sections. Mast cell volume density was significantly (P < 0.05) higher in IBS (0.91 +/- 0.18; CI 0.79; 1.0) than normal controls (0.55 +/- 0.14; CI 0.40; 0.69) in the caecum but not at other sites. Apart from MC, there was no evidence of increased cellular infiltrate in the IBS group. MC were significantly increased in the caecum of IBS patients compared to controls. The multiple effects of the intestinal mast cell alone, or as a participant of a persistent inflammatory response, may be fundamental to the pathogenesis of IBS.  相似文献   
99.
The third edition of the British Transplantation Society Guidelines for the Prevention and Management of CMV Disease after Solid Organ Transplantation was published in March 2011. This article summarizes the important changes and advances in management in this rapidly evolving field. The pros and cons of universal, or targeted anti-cytomegalovirus (CMV) prophylaxis, and pre-emptive anti-CMV therapy are discussed, especially with respect to advances in CMV polymerase chain reaction monitoring. The evidence for oral anti-CMV prophylaxis using valganciclovir is presented, together with a summary of the treatment of CMV disease and emerging fields such as CMV vaccination, CMV genotyping, and drug resistance.  相似文献   
100.
The New York City Board of Health (NYCBH) vaccinia virus (VACV) vaccine strain was deleted for the immune evasion gene, E3L, and tested for its pathogenicity and ability to protect mice from heterologous challenge with ectromelia virus (ECTV). NYCBHΔE3L was found to be highly attenuated for pathogenicity in a newborn mouse model and showed a similar attenuated phenotype as the NYVAC strain of vaccinia virus. Scarification with one or two doses of the attenuated NYCBHΔE3L was able to protect mice equally as well as NYCBH from death, weight loss, and viral spread to visceral organs. A single dose of NYCBHΔE3L resulted in low poxvirus-specific antibodies, and a second dose increased levels of poxvirus-specific antibodies to a level similar to that seen in animals vaccinated with a single dose of NYCBH. However, similar neutralizing antibody titers were observed following one or two doses of NYCBHΔE3L or NYCBH. Thus, NYCBHΔE3L shows potential as a candidate for a safer human smallpox vaccine since it protects mice from challenge with a heterologous poxvirus.  相似文献   
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