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We report a patient with congenital Chagas disease in Japan. This report reemphasizes the role of neglected and emerging tropical diseases in the era of globalization. It also indicates the need for increased vigilance for detecting Chagas disease in non–disease-endemic countries.  相似文献   
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Background

A pulmonary hypertensive crisis (PHC) can be a life-threatening condition. We established a PHC model by exposing rats with monocrotaline (MCT)-induced pulmonary hypertension to acute hypoxia, and investigated the effects of vasopressin, phenylephrine, and norepinephrine on the PHC.

Methods

Four weeks after MCT 60 mg kg?1 administration i.v., right ventricular systolic pressure (RVSP), systolic BP (SBP), mean BP (MBP), cardiac index (CI), and pulmonary vascular resistance index (PVRI) were measured. PHC defined as an RVSP exceeding or equal to SBP was induced by changing the fraction of inspiratory oxygen to 0.1. Rats were subsequently treated by vasopressin, phenylephrine, or norepinephrine, followed by assessment of systemic haemodynamics, isometric tension of femoral and pulmonary arteries, cardiac function, blood gas composition, and survival.

Results

PHC was associated with increased RV dilatation and paradoxical septal motion. Vasopressin increased MBP [mean (standard error)] from 52.6 (3.8) to 125.0 (8.9) mm Hg and CI from 25.4 (2.3) to 40.6 (1.8) ml min?1 100 g?1 while decreasing PVRI. Vasopressin also improved RV dilatation, oxygenation, and survival in PHC. In contrast, phenylephrine increased MBP from 54.8 (2.3) to 96.8 (3.2) mm Hg without improving cardiac pump function. Norepinephrine did not alter MBP. Vasopressin contracted femoral but not pulmonary arteries, whereas phenylephrine contracted both arterial beds. Hence, improvements with vasopressin in PHC might be associated with decreased PVRI and selective systemic vasoconstriction.

Conclusions

In this rat model of a PHC, vasopressin, but not phenylephrine or norepinephrine, resulted in better haemodynamic and vascular recovery.  相似文献   
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Aim: Although the treatment of early gastric cancer with endoscopic submucosal dissection (ESD) has been widely carried out, a standardized method of sedation for ESD has not been established. The purpose of the present study was to evaluate the efficacy and safety of sedation with dexmedetomidine (DEX). Methods: We conducted a randomized study involving 90 patients with gastric tumors who were intended to be treated with ESD. The patients were sedated either with DEX (i.v. infusion of 3.0 µg/kg per h over 5 min followed by continuous infusion at 0.4 µg/kg per h [n = 30]), propofol (PF [n = 30]), or midazolam (MDZ [n = 30]). In all groups, 1 mg MDZ was added i.v. as needed. Results: En bloc resection of the gastric tumor was achieved in 88 (98%) patients. None of the DEX‐sedated patients showed a significant reduction of the oxygen saturation level. The percentage of patients who showed body movement in the DEX group was significantly lower than those in the PF and MDZ groups, and the mean dose of additional MDZ in the DEX group was significantly smaller than that in the MDZ group. The rate of effective sedation was significantly higher in the DEX group compared with the MDZ or PF group. The mean length of ESD in the DEX group was 65 min, which was significantly shorter than in the other two groups. No DEX‐sedated patient developed major surgical complications. Conclusions: Sedation with DEX is effective and safe for patients with gastric tumors who are undergoing ESD.  相似文献   
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Several studies have suggested that rheumatoid arthritis (RA) is uncommon in rural sub-Saharan Africa. The aim of this study is to determine the potential differences between patients with RA living in rural areas and those living in urban areas. We performed a cross-sectional study from June 2006 to May 2009. We included all patients with RA (1987 ACR criteria) seen at the Rheumatology Unit of the Le Dantec Teaching Hospital, Dakar, Senegal. We compared the main socio-demographic and clinical characteristics of patients living in rural areas to those living in urban areas. We included 180 patients in our study, of whom, 143 (79.4?%) lived in urban areas and 37 (20.6?%) in rural areas. The median age was 44?years [range 34–55] in patients from rural areas vs. 41?years [range 30–53] in patients from urban areas, without any statistical significance (p?=?0.24). Patients under the age of 60 mostly lived in urban areas (p?=?0.03). The extra-articular manifestations were significantly more frequent in patients living in rural areas (p?=?0.02). There was no statistical significance when comparing the delay in diagnosis, number of swollen joints, disease activity, hand deformities, and concentration of autoantibodies (RF and ACPA) in both populations. The percentage of patients seen from the rural areas of Senegal is low (20.6?%) compared to those seen from the urban areas. The number of extra-articular manifestations is the main difference between patients living in rural and urban areas. The role played by environmental factors seems important. Further incidence studies are needed.  相似文献   
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We present a patient who had adult-onset Still’s disease (AOSD) complicated by thrombotic thrombocytopenic purpura (TTP) that resulted in retinal microangiopathy and rapidly fatal cerebral edema. The patient was a 37-year-old male who developed fever, eruption, arthritis and hepatic dysfunction, that, based on close examination, was diagnosed as AOSD. Despite treatment with corticosteroids, the patient developed acute visual field defect, neurological deterioration including convulsions and impaired consciousness, as well as acute renal failure that ultimately resulted in death. Pathological examination of autopsy specimens revealed multiple fibrin thrombi disseminated in small vessels of the brain and kidney, which was consistent with TTP, along with marked cerebral edema. Although TTP has rarely been reported in association with AOSD, awareness of the possible coexistence of these two diseases is important for diagnosis and treatment.  相似文献   
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