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1.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
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OBJECTIVES: Assessment of morphological characteristics of lymphnodes studied ex-corpore by echoendoscopy--shape, sharpness of limits, echogenicity and dimensions--to categorize them either as metastatic or non-metastatic. MATERIAL AND METHODS: Fifty-four lymphnodes were studied. They were identified and studied by echoendoscopy in fresh surgical specimens of oesophagus, stomach and rectum. Eight nodal characteristics were evaluated. The data obtained were studied by multivariate analysis using the logistical estimate method in two different statistical models. RESULTS: In model 1, logistical estimate demonstrated that well-defined limits (WDL) of the lymphnodes and the association of hypoechogenicity and round shape were the most significant variables suggesting the presence of invasion. In model 2, the most significant variables were WDL, round shape and association of round shape with WDL. The first model had a high sensitivity of 93.1% and specificity of 68% whereas the second model had a greater specificity of 84%, with a slight fall in sensitivity. CONCLUSION: These models might have an application to clinical practice particularly in the pre-operative assessment of patients with oesophageal carcinoma, gastric carcinoma or rectal carcinoma.  相似文献   
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The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.  相似文献   
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Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.  相似文献   
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Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.  相似文献   
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SUMMARY Serum potassium was measured within 24 hours in 156 patients (48 male, 108 female) with an average age of 81.9 years admitted to the unit with acute illness. Of the 156 patients, 88 (56.4%) were taking diuretics (none was on ACE inhibitors); 20 patients (12.8%) were also on digoxin therapy. In all, 24 patients (16%) had hypokalaemia and 3 (2%) hyperkalaemia. Hypokalaemia was seen in patients associated with acute illness. There was no significant difference between the diuretic and non-diuretic groups. Monitoring of serum potassium is not routinely indicated to detect hypokalaemia in patients on diuretic therapy except in those with severe hepatic or renal impairment or those on digoxin.  相似文献   
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Familial amyloid polyneuropathy (FAP) is characterized by deposition of mutated transthyretin (TTR) in the peripheral nervous system. Prior to amyloid fibrils, nonfibrillar TTR aggregates are deposited inducing oxidative stress with increased nitration (3-NT). As the major source of TTR is the liver, liver transplantation (LT) is used to halt FAP. Given the shortage of liver donors, domino LT (DLT) using FAP livers is performed. The correlation between TTR deposition in the skin and nerve was tested in biopsies from normal individuals, asymptomatic carriers (FAP 0) and FAP patients; in FAP 0, nonfibrillar TTR was observed both in the skin and nerve in the same individuals; in patients, amyloid was detected in both tissues. The occurrence of amyloidosis in recipients of FAP livers was evaluated 1-7 years after DLT: TTR deposition occurred in the skin 3 years after transplantation either as amyloid or aggregates; in one of the recipients, fibrillar TTR was present in the epineurium 6 years after DLT. Deposits were scarce and 3-NT immunostaining was irrelevant. Nerve biopsies from DLT recipients had no FAP-related neuropathy. Our findings suggest that TTR amyloid formation occurs faster than predicted and that TTR of liver origin can cross the blood-nerve barrier. Recipients of FAP livers should be under surveillance for TTR deposition and tissue damage.  相似文献   
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Achromatopsia is an autosomal recessive disease of the retina, characterized clinically by an inability to distinguish colors, impaired visual acuity, nystagmus and photophobia. A genome-wide search for linkage was performed using an inbred Jewish kindred from Iran. To facilitate the genome-wide search, we utilized a DNA pooling strategy which takes advantage of the likelihood that the disease in this inbred kindred is inherited by all affected individuals from a common founder. Equal molar amounts of DNA from all affected individuals were pooled and used as the PCR template for short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected members of the kindred was used as a control. A reduction in the number of alleles in the affected versus control pool was observed at several loci. Upon genotyping of individual family members, significant linkage was established between the disease phenotype and markers localized on chromosome 2. The highest LOD score observed was 5.4 (theta = 0). When four additional small unrelated families were genotyped, the combined peak LOD score was 8.2. Analysis of recombinant chromosomes revealed that the disease gene lies within a 30 cM interval which spans the centromere. Additional fine-mapping studies identified a region of homozygosity in all affected individuals, narrowing the region to 14 cM. A candidate gene for achromatopsia was excluded from this disease interval by radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an essential first step in the identification of the disease-causing gene.   相似文献   
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