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801.
BACKGROUND: Patients undergoing EUS usually receive intravenously administered sedative medication. A double-blind, prospective, randomized trial was conducted to compare midazolam with a placebo for EUS of the esophagus and stomach and to assess patient tolerance and endoscopic feasibility. METHODS: A total of 111 patients were randomized to receive midazolam or a placebo. Patients used a visual analogue scale to score pre-EUS anxiety and tolerance for the procedure. Endoscopists used a visual analogue scale to score ease of echoendoscope introduction and overall patient cooperation. Subsequent to EUS, patients were asked if they were willing to undergo the procedure under the same conditions. RESULTS: The patients' visual analogue scale scores indicated that tolerance for the introduction of the echoendoscope and the procedure overall were both significantly better in the midazolam group. Overall patient tolerance was predicted by sedation (p < 0.001) and pre-EUS anxiety (p = 0.024). Endoscopists' visual analogue scale scores showed that ease of echoendoscope introduction was significantly better in the midazolam group. There was no significant difference in overall patient cooperation during the procedure. There were no significant differences in introduction time, total procedure time, or patients' willingness to undergo the procedure under the same conditions. CONCLUSIONS: EUS of the esophagus and stomach without intravenous sedation is feasible for endoscopists and patients. Patients prefer intravenous administration of midazolam. Assessment of anxiety before EUS may indicate whether administration of midazolam can improve tolerance for the individual patient.  相似文献   
802.
BACKGROUND: As stress may be involved in the generation of functional dyspeptic symptoms, we evaluated the effect of the stress hormone, corticotropin-releasing hormone, on proximal stomach function. Twelve healthy volunteers [six women; 23 years (20-26 years)] underwent a barostat study on 2 days. During the infusion of corticotropin-releasing hormone (2.3 microg/kg/h) or saline, a stepwise distension protocol was performed followed by ingestion of a liquid meal (Nutridrink, 200 ml, 300 kcal). RESULTS: Corticotropin-releasing hormone infusion induced a significant increase in cortisol levels and basal volumes compared with placebo. The threshold for discomfort, meal-induced accommodation, dyspeptic symptoms, heart rate and blood pressure were all not significantly altered by corticotropin-releasing hormone infusion. CONCLUSION: In healthy volunteers, peripheral infusion of corticotropin-releasing hormone reduces basal fundic tone, but has no effect on meal-induced accommodation or visceral sensitivity to gastric distension. Our findings suggest that in healthy volunteers, peripheral corticotropin-releasing hormone seems not to be involved in the onset of dyspeptic symptoms.  相似文献   
803.
Ninety patients with pancreatic duct, distal bile duct, and ampullary carcinoma underwent pancreatic resection. Following a standard policy of resection based on surgical findings, all the patients who had resection first underwent subtotal extended pancreatectomy (n = 68) and if they were considered not to fulfill the criteria for this operation, total pancreatectomy (n = 22). Thus, 68 of the 90 patients (72%) were managed with subtotal pancreatic resection irrespective whether they had ampullary, pancreatic duct, or distal common bile duct carcinoma. On the basis of our results, subtotal duodenopancreatectomy is regarded as the method of choice for many patients with pancreatic duct, distal bile duct, or ampullary carcinoma.  相似文献   
804.
BACKGROUND AND STUDY AIMS: Distal esophageal carcinomas can be resected using transthoracic esophagectomy or transhiatal esophagectomy. Accurate diagnosis of subcarinal and supracarinal lymph-node metastases is important for selecting the surgical strategy. The impact of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) on the preoperative diagnosis of subcarinal and supracarinal lymph-node metastases in patients with distal esophageal carcinoma was therefore investigated. PATIENTS AND METHODS: Patients with a resectable distal esophageal carcinoma and subcarinal and/or supracarinal lymph nodes visualized on preoperative EUS were prospectively included. The lymph nodes were sampled using EUS-FNA, and if they were found to have metastases, transthoracic resection was offered; by contrast, patients without metastases were offered a transhiatal resection. RESULTS: Lymph-node metastases were found with EUS-FNA in 11 of the 48 patients included (23 %). Thirteen patients had suspicious nodes on EUS, in four of whom (31 %) the diagnosis was changed into nonmalignant nodes with FNA. Thirty-five patients had nonsuspicious nodes on EUS, in three of whom (9 %) the FNA procedure revealed malignant cells. CONCLUSIONS: EUS with the addition of the FNA procedure has a significant impact on decision-making in patients with esophageal carcinoma in whom transhiatal esophagectomy would otherwise be planned.  相似文献   
805.
OBJECTIVES: The aetiology of primary sclerosing cholangitis (PSC) is unknown, and the role of micro-organisms has been studied only to a limited extent. We tested the hypothesis that past or persisting infection with common viruses or atypical bacteria might play a role in genetically susceptible hosts. DESIGN: Case-control study. METHODS: Serological screening for antibodies against 22 viruses as well as Chlamydia spp. and Mycoplasma pneumoniae was carried out in 41 well-established PSC patients. All 5110 sera tested in 1997 for these micro-organisms at our laboratory served as a background reference group. Subsequently, Chlamydia anti-lipopolysaccharide (LPS) antibodies were determined by enzyme-linked immunosorbent assay (ELISA) in the PSC group and in three race-matched control groups (inflammatory bowel disease (IBD) group, n = 35; non-IBD patients group, n = 39; healthy blood donor group, n = 40). Subtyping in Chlamydia trachomatis and C. pneumoniae serotypes by specific anti-major outer membrane protein (MOMP) assays was carried out in the four groups. Immunohistochemical staining using specific markers for chlamydiae was carried out on liver biopsies of 14 PSC patients. RESULTS: There was a markedly elevated seroprevalence of Chlamydia-LPS antibodies compared with the 1997 reference group. The odds ratios (ORs) for the presence of immunoglobulin G, immunoglobulin M and immunoglobulin A antibodies for the PSC patients versus the control group were 2.4 (95% confidence interval (CI) 1.1 to 5.4), 1.9 (95% CI 0.9 to 4.0) and 6.7 (95% CI 3.0 to 17.0), respectively. All other micro-organisms tested showed normal antibody profiles that did not differ from the 1997 reference group. The seroprevalence of Chlamydia-anti-LPS antibodies was elevated markedly in the PSC patients compared with the IBD, non-IBD and blood donor groups. The outcomes in the C. trachomatis and C. pneumoniae anti-MOMP assays did not correlate with the anti-LPS-positive PSC sera. The actual presence of Chlamydia bodies in liver tissue could not be demonstrated. CONCLUSION: Our findings suggest an association between PSC and (previous) infection with Chlamydia.  相似文献   
806.
BACKGROUND: T cells play an important part in Crohn's disease. Immunomodulating therapies that target T cell activation may have clinical effects in Crohn's disease. AIM: To investigate the toxicity and potential efficacy of anti-CD4 monoclonal antibody therapy in patients with Crohn's disease. PATIENTS AND METHODS: A dose escalating pilot study was conducted in three groups of four patients with intractable Crohn's disease, refractory to steroids. They received 70, 210, or 700 mg of cM-T412, a depleting anti-CD4 monoclonal antibody (mAb). RESULTS: The mean reduction in Crohn's disease activity index (CDAI) was respectively 25%, 24%, and 36% at four weeks, and 24% and 52% at 10 weeks in the 210 mg and 700 mg groups. There was only a minor effect on endoscopically evaluated disease activity. Side effects were mild to moderate fever with chills and headache. No signs of opportunistic infection were seen. There was a sustained decrease in CD4 count which lasted at least four weeks in the 70 mg group (76.3 (SD 40.6)% of the baseline value), and 10 weeks in both the 210 mg group (80.8 (SD 60.9)%) and the 700 mg group (24.8 (SD 15.4)%). The primary and secondary humoral immune response was not influenced by anti-CD4 mAb treatment. CONCLUSION: This study shows the moderate potential efficacy of treatment of patients with Crohn's disease using a depleting chimeric monoclonal anti-CD4 antibody.  相似文献   
807.
Gambierol is a marine polycyclic ether toxin belonging to the group of ciguatera toxins. It does not activate voltage-gated sodium channels (VGSCs) but inhibits Kv1 potassium channels by an unknown mechanism. While testing whether Kv2, Kv3, and Kv4 channels also serve as targets, we found that Kv3.1 was inhibited with an IC50 of 1.2 ± 0.2 nM, whereas Kv2 and Kv4 channels were insensitive to 1 μM gambierol. Onset of block was similar from either side of the membrane, and gambierol did not compete with internal cavity blockers. The inhibition did not require channel opening and could not be reversed by strong depolarization. Using chimeric Kv3.1–Kv2.1 constructs, the toxin sensitivity was traced to S6, in which T427 was identified as a key determinant. In Kv3.1 homology models, T427 and other molecular determinants (L348, F351) reside in a space between S5 and S6 outside the permeation pathway. In conclusion, we propose that gambierol acts as a gating modifier that binds to the lipid-exposed surface of the pore domain, thereby stabilizing the closed state. This site may be the topological equivalent of the neurotoxin site 5 of VGSCs. Further elucidation of this previously undescribed binding site may explain why most ciguatoxins activate VGSCs, whereas others inhibit voltage-dependent potassium (Kv) channels. This previously undescribed Kv neurotoxin site may have wide implications not only for our understanding of channel function at the molecular level but for future development of drugs to alleviate ciguatera poisoning or to modulate electrical excitability in general.  相似文献   
808.
BACKGROUND: The Los Angeles classification of reflux oesophagitis includes sharply demarcated areas of erythema without any associated slough within the definition of reflux-induced mucosal breaks, though there is uncertainty as to whether these "red streaks" actually represent such a mucosal lesion. This study evaluates the histopathology of these red streaks. METHODS: Forty patients with one or more red streaks on the tops of the mucosal folds in the distal oesophagus were included in a multinational, multicentre prospective study. All patients were referred for upper gastrointestinal endoscopy to investigate chronic heartburn and acid regurgitation. Biopsies were taken from the red streaks and from control biopsies from more normal appearing mucosa 1 cm lateral to the red streaks. A two-sided probability test using normal approximation assessed differences in the histological findings at the two biopsy locations. RESULTS: Compared to control biopsies, biopsies of red streaks had a significantly thicker basal cell layer (mean +/- s 41% +/- 32% versus 18% +/- 23% of mucosal thickness, P=0.001) and longer papillae (mean +/- s 71% +/- 19% versus 49% +/- 24% of mucosal thickness, P= 0.001). Of the red streak biopsies, 25% had either newly re-epithelized lesions or granulation tissue beneath squamous epithelium. Only 10% of the control biopsies had moderate or more marked regenerative changes (based on elongation of papillae and basal cell hyperplasia), compared to 65.1% of red streak biopsies. Of the biopsies from the red streak itself, 7% showed no abnormality and 27.9% only slight changes. In comparison, 25% of the biopsies from control biopsies showed no regenerative changes and 62.5% only slight change due to gastro-oesophageal reflux disease. CONCLUSION: The histomorphological counterpart to the endoscopically visible red streaks of the distal oesophagus is marked regenerative changes of the squamous epithelium and/or capillary rich granulation tissue beneath the squamous epithelium. Red streaks are validated as being indicative of acid/peptic mucosal injury, but they do not satisfy a strict definition of a mucosal break.  相似文献   
809.
Yang  G; Ulrich  PP; Aiyer  RA; Rawal  BD; Vyas  GN 《Blood》1993,81(4):1083-1088
Blood donations are routinely screened by multiple serologic assays for antigens/antibodies associated with infection by blood-borne viruses, including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1 and HIV-2), and human T-cell lymphotropic virus (HTLV-I and HTLV-II). A direct detection of these viruses would be more effective for the prevention of transfusion- transmitted infections than the indirect measurement of the variable host immune response to these agents. Because the polymerase chain reaction (PCR) for viral gene amplification offers the most sensitive and direct means of detecting viruses in blood, we have developed a nonisotopic PCR procedure for the detection of HBV, chosen as a prototype. The problems, common to previously described PCR methods, of nucleic acid extraction and inhibition of the PCR by plasma proteins were overcome by isolation of HBV from plasma by means of 450-microns polystyrene beads covalently coated with monoclonal antibody to the Pre- S1 region of the viral envelope protein. Detergent lysis and proteinase K digestion of the immunocaptured virions isolated from plasma released the HBV DNA. A modified PCR-amplification protocol, incorporating digoxigenin-labeled dUTP in the amplified gene products followed by hybridization with a specific biotinylated oligonucleotide probe bound to streptavidin-coated 2.8-microns magnetic beads, allowed flow cytometric analyses of HBV-specific PCR products by means of antibodies to digoxigenin labeled with fluorescein isothiocyanate. The endpoint serial dilutions of pedigreed human plasma samples containing chimpanzee infectious dose (CID50) of 10(7) for adw and CID50 of 10(7.5) for the ayw subtypes were compared in repeated testing of PCR products by our immunoreactive bead (PCR-IRB) assay. HBV DNA was consistently detected in a 5 x 10(-10) dilution of each sample. In testing 20 coded specimens of blood donors, with or without serologic markers of HBV infection, the PCR-IRB was specific and more sensitive than the PCR analyses by slot blot hybridization with radioactive probe. The PCR-IRB assay can be adapted for simultaneous detection of multiple blood-borne viruses by an automated flow cytometric analysis system.  相似文献   
810.
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