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Cholangitis and pancreatitis associated with cytomegalovirus (CMV) infection in an immunocompetent patient is reported. Endoscopic retrograde cholangiography performed on a 55-year-old man for evaluation of the cause of jaundice and liver dysfunction revealed a distal focal irregular narrowing of the common bile duct. Microscopic findings of the resected specimen showed chronic cholangitis and CMV pancreatitis. Immunohistochemistry disclosed that epithelial cells in the inflamed bile duct were positive for CMV antigen, which was compatible with CMV cholangitis. Inflammation of the biliary tract or pancreas by CMV has been commonly reported as a complication in immunocompromised patients. Our report appears to be a rare case, but suggests that CMV cholangitis or pancreatitis should be considered in the differential diagnoses of common bile duct stenosis or pancreatitis even in immunocompetent individuals.  相似文献   
33.
We have recently shown that systemic administration of a superoxide dismutase mimetic, tempol, resulted in decreases in mean arterial pressure and heart rate along with a reduction in renal sympathetic nerve activity (RSNA). It has also been shown that these parameters are significantly increased by systemic administration of a superoxide dismutase inhibitor, diethyldithio-carbamic (DETC), indicating a potential role of reactive oxygen species in the regulation of RSNA. In this study, we examined the effects of local administrations of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (tempol) and DETC on RSNA in anesthetized rats. Either tempol or DETC was directly administered onto the renal sympathetic nerves located between the electrode and ganglion. Local application of tempol (10 microL, 0.17 to 1.7 mol/L, n=6) resulted in dose-dependent decreases in integrated RSNA (by -81+/-6% at 1.7 mol/L) without alterations in mean arterial pressure and heart rate. In contrast, DETC (10 microL, 0.17 to 1.7 mol/L, n=6) increased RSNA dose-dependently. The responses of RSNA to tempol and DETC were significantly greater in spontaneously hypertensive rats than in normotensive rats (n=6, respectively). Local application of sodium nitroprusside (1 mmol/L) or N(G)-nitro-L-arginine methyl ester (0.11 mol/L) altered neither basal RSNA nor tempol-induced reductions in RSNA (n=6 and 5, respectively). A voltage-gated potassium channel blocker, 4-aminopyridine (0.1 mol/L), significantly decreased basal RSNA (by -81+/-1%) and completely prevented DETC-induced increases in RSNA (n=5). These results suggest that reactive oxygen species play a role in the regulation of peripheral sympathetic nerve activity, and that at least part of this mechanism is mediated through voltage-gated potassium channels.  相似文献   
34.
Primary squamous cell carcinoma is rarely observed, with a reported incidence of 0.04–0.07 % of all gastric cancers. An 81-year-old male underwent chemoradiotherapy for type 1 gastric cancer of the posterior wall of the cardiac region in 2005. The tumor disappeared after 1 year of therapy, following which an area of white epithelium, approximately 30 mm in diameter and continuous with the esophageal mucosa, became visible. Biopsy of the white epithelium indicated normal squamous epithelium. An elevated lesion was subsequently detected in the area of white epithelium on upper gastrointestinal endoscopy during a follow-up examination 5 years after therapy. As a biopsy of the same site indicated squamous cell carcinoma, we performed endoscopic submucosal dissection. Histopathological examination indicated high-grade fibrosis due to radiotherapy and showed a moderately differentiated squamous cell carcinoma invading the scarred portion. We describe a case where the developmental process of a squamous cell carcinoma was observed using endoscopy, including narrow band imaging with magnification. This carcinoma likely originated from squamous metaplasia that developed after chemoradiotherapy was administered for a gastric cancer.  相似文献   
35.
Synthetic polymer nanoparticles (NPs) that bind venomous molecules and neutralize their function in vivo are of significant interest as "plastic antidotes." Recently, procedures to synthesize polymer NPs with affinity for target peptides have been reported. However, the performance of synthetic materials in vivo is a far greater challenge. Particle size, surface charge, and hydrophobicity affect not only the binding affinity and capacity to the target toxin but also the toxicity of NPs and the creation of a "corona" of proteins around NPs that can alter and or suppress the intended performance. Here, we report the design rationale of a plastic antidote for in vivo applications. Optimizing the choice and ratio of functional monomers incorporated in the NP maximized the binding affinity and capacity toward a target peptide. Biocompatibility tests of the NPs in vitro and in vivo revealed the importance of tuning surface charge and hydrophobicity to minimize NP toxicity and prevent aggregation induced by nonspecific interactions with plasma proteins. The toxin neutralization capacity of NPs in vivo showed a strong correlation with binding affinity and capacity in vitro. Furthermore, in vivo imaging experiments established the NPs accelerate clearance of the toxic peptide and eventually accumulate in macrophages in the liver. These results provide a platform to design plastic antidotes and reveal the potential and possible limitations of using synthetic polymer nanoparticles as plastic antidotes.  相似文献   
36.
Furuta T  Takemura M  Tsujita J  Oku Y 《Dysphagia》2012,27(1):94-100
Swallowing disorders are a common complaint among the elderly. Recently, surface electrical stimulation applied to the neck region has received increased attention as a new modality to treat pharyngeal dysphagia. Previous reports used pulsed current at a frequency range of 1-120 Hz. Kilohertz-frequency alternating currents (ACs) have not been tested for treating dysphagia. Therefore, we evaluated the effects of interferential currents (IFCs), the most popular modality of amplitude-modulated kilohertz-frequency ACs in clinical practice, on the swallowing reflex in healthy subjects. We found that IFC stimulation at the sensory threshold with 50-Hz modulation significantly increased the number of swallows without any discomfort, but pure AC stimulation at the carrier frequency did not have a significant effect. There was no statistically significant difference in the time course of the number of swallows among 1,000-, 2,000-, 4,000-, and 6,000-Hz carrier frequencies. The number of swallows remained increased during the 15-min IFC stimulation, suggesting that IFC stimulation facilitates the swallowing reflex without adaptation, at least during this stimulation period. We suggest that an IFC stimulation or a low-frequency, modulated kilohertz AC stimulation, which would be more comfortable than pulsed currents, is an alternative stimulation mode for treating pharyngeal dysphagia.  相似文献   
37.
Japanese Journal of Ophthalmology - To determine the incidence of rhegmatogenous retinal detachments (RRDs) and proliferative vitreoretinopathies (PVRs) and their distribution by age and sex in...  相似文献   
38.

Purposes

The purpose of this study was to show the clinical features of up-front surgery of the primary tumor in asymptomatic patients with incurable colorectal PC.

Methods

Forty-six patients that were diagnosed between 1998 and 2007 with asymptomatic colorectal PC who could not be successfully cured by surgery were assessed retrospectively.

Results

A univariate analysis revealed the presence of liver metastases, without the use of oxaliplatin (OX)/irinotecan (IRI) and without a primary tumor resection to be poor prognostic factors for survival (p = 0.044, p = 0.030, p < 0.001, respectively). According to a multivariate analysis, no use of OX/IRI and no primary tumor resection, were found to be independent poor prognostic factors for survival (HR 2.57; p = 0.047, HR 6.62; p = 0.003, respectively). The median survival time of patients treated with and without OX/IRI was 18 and 7 months, respectively. The median survival time of patients with and without primary tumor resection was 10 and 2 months, respectively. The number of patients needing surgical intervention for intestinal obstruction after surgery significantly increased in patients treated with OX/IRI (p = 0.001).

Conclusion

Improvement of survival may be related to widespread use of modern systemic chemotherapy and primary tumor resection. However, an increased number of patients that needed surgery for an intestinal obstruction were observed, even after up-front surgery, when patients were treated with modern systemic chemotherapy.  相似文献   
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