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Testicular vasculitis is a very rare extra-articular manifestation of rheumatoid arthritis (RA). We describe the case of a 53-year-old man diagnosed with RA for eight years, who was poorly controlled and developed rheumatoid vasculitis, which manifested as leg ulcers and peripheral polyneuropathy. The patient also had acute neutrophilic meningitis and was treated with antibiotics and intravenous pulse therapy with methylprednisolone (500 mg daily) for three days, followed by oral cyclophosphamide (2 mg/kg daily) and prednisone. Overall improvement was observed, and the patient was discharged. But 15 days later, the meningitis recurred, and the patient was readmitted and treated again with antibiotics. Three days later, he developed pain and enlargement of his left testicle with gangrene. Unilateral orchiectomy was performed, revealing lymphocytic vasculitis. The patient died two days later due to aspiration pneumonia. This case illustrates a rare and severe manifestation of rheumatoid vasculitis.  相似文献   
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Background: Diabetes mellitus (DM) involves metabolic changes that can negatively influence periodontal tissues, resulting in more prevalent and severe periodontitis and impaired bone formation. Occlusal trauma (OT) is an injury of the supportive periodontium that results in bone loss. It can be hypothesized that DM would increase bone loss after OT, mainly when associated with periodontitis. Thus, the aim of the present study is to evaluate the influence of DM on bone response in the furcation area of teeth subjected to OT in the presence, or absence, of experimental periodontitis (EP) in the rat model. Methods: Thirty-two male Wistar rats were assigned to four groups: 1) group 1 (G1): DM+OT+EP (n = 8); 2) group 2 (G2): DM+OT (n = 8); 3) group 3 (G3): OT+EP (n = 8); and 4) group 4 (G4): OT (n = 8). G1 and G2 received a single intraperitoneal injection of streptozotocin (STZ). After 10 days, G1 and G3 were subjected to EP by ligature placement. Fifteen days after the start of EP, OT was induced by the creation of a premature contact. The animals were euthanized 35 days after DM induction. Results: DM enhanced bone loss in the presence of OT combined with EP, but did not increase bone loss in teeth subjected to OT alone. EP caused greater bone loss when associated with OT. Conclusion: Within the limits of this animal study, it can be concluded that DM enhances bone loss in the presence of occlusal trauma associated with EP.  相似文献   
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This article reports a rare case of extensive palatal pigmentation secondary to long-term chloroquine treatment. Chloroquine was originally used as an antimalarial agent, but it is now widely used as an adjunct in the treatment of autoimmune diseases. Adverse effects of chloroquine usually include skin changes such as bullous pemphigoid, exacerbation of psoriasis, and pigmentation of the skin and mucous membranes as well as retinopathy, gastrointestinal alterations, and neuromuscular disorders. Extensive oral pigmentation is an uncommon feature of an adverse drug effect, and diagnosis should be based on clinicopathological findings.  相似文献   
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Recent work in experimental neurophysiology has identified distinct neuronal populations in the rodent brain stem and hypothalamus that selectively promote wake and sleep. Mutual inhibition between these cell groups has suggested the conceptual model of a sleep-wake switch that controls transitions between wake and sleep while minimizing time spent in intermediate states. By combining wake- and sleep-active populations with populations governing transitions between different stages of sleep, a "sleep-wake network" of neuronal populations may be defined. To better understand the dynamics inherent in this network, we created a model sleep-wake network composed of coupled relaxation oscillation equations. Mathematical analysis of the deterministic model provides insight into the dynamics underlying state transitions and predicts mechanisms for each transition type. With the addition of noise, the simulated sleep-wake behavior generated by the model reproduces many qualitative and quantitative features of mouse sleep-wake behavior. In particular, the existence of simulated brief awakenings is a unique feature of the model. In addition to capturing the experimentally observed qualitative difference between brief and sustained wake bouts, the model suggests distinct network mechanisms for the two types of wakefulness. Because circadian and other factors alter the fine architecture of sleep-wake behavior, this model provides a novel framework to explore dynamical principles that may underlie normal and pathologic sleep-wake physiology.  相似文献   
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The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported.  相似文献   
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