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Purpose

This report describes an attempt to reduce the expression level of Hanganutziu–Deicher (H–D) antigens by small interfering RNA (siRNA) for pig cytidine monophospho-N-acetylneuraminic acid hydroxylase (pCMAH).

Methods

A pig endothelial cell (PEC) line, and PEC and fibroblasts from an α1,3galactosyltransferase knockout (GalT-KO) piglet were used. Real-time PCR was used to evaluate the degradation of mRNA by siRNA. The H–D antigen was stained, and then the cells were incubated with human serum for the FACS analysis. The extent of lysis in human serum was next calculated using an LDH assay.

Results

Suppression of the mRNA of pCMAH by each siRNA was first determined. The mixture of siRNAs for pCMAH reduced the expressions of the H–D antigen on the PEC and fibroblasts to a considerable extent. The further reduction in the xenoantigenicity for human serum of the GalT-KO cells was then confirmed. In addition, the PEC line showed a significant downregulation in complement-dependent cytotoxicity by the siRNAs, thus indicating that the anti-H–D antigen in human serum is capable of causing lysis of the pig cells.

Conclusion

pCMAH silencing by siRNA reduced the expression of the H–D antigen and its antigenicity, thus confirming that the H–D antigen is one of the major non-Gal antigens in this situation.  相似文献   
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Background/ObjectivesWe aimed to examine therapeutic efficacy and prognosis prediction of autoimmune pancreatitis (AIP) using shear wave elastography (SWE) and shear wave dispersion (SWD) in transabdominal ultrasound (US).MethodsThe subjects were 23 patients with diffuse type 1 AIP who underwent SWE and SWD, and 34 controls with a normal pancreas. Elasticity and dispersion were defined as the pancreatic elastic modulus (PEM) and dispersion slope, respectively. PEM and dispersion slope were compared between AIP and control cases, and the short-term therapeutic effect and long-term prognosis were examined.ResultsPEM (30.9 vs. 6.6 kPa, P < 0.001) and dispersion slope (15.3 vs. 13.0 (m/sec)/kHz, P = 0.011) were significantly higher in AIP cases than in controls. Among the 17 AIP patients followed-up in two weeks after treatment, these parameters were 12.7 kPa and 10.5 (m/sec)/kHz with median decrease rate of 37.2% and 32.8%, respectively, which were significantly higher than the change in the size of pancreatic parenchyma (14.4%, P = 0.026). Fourteen of these subjects were followed up for >12 months, during which 2 had relapse; diabetes improved in 5 and worsened in 2; in 60% of cases, the pancreatic parenchyma was atrophied. The % change in PEM after two weeks was tended to be higher in non-atrophy cases.ConclusionSWE and SWD measurement in US may be useful for quantitative assessment of AIP and evaluation of short-term treatment efficacy.  相似文献   
46.
A case of generalized peritonitis, secondary to a perforation of the rectosigmoid colon during barium-enema roentgenography, is presented. The patient required immediate surgical intervention with the prime importance of the treatment being removal of as much of the contaminating materials as possible. This was done successfully with irrigation and wiping, using urokinase solution. Peritoneal lavage with urokinase solution was also carried out in the early postoperative period. Fluid replacement with careful monitoring of fluid and electrolyte balance is essential before, during, and after the surgical procedure. Adequate antibiotic therapy and careful respiratory and nutritional support are also important.  相似文献   
47.
Background The relationship between endoscopic appearances such as endoscopic gastritis and duodenitis and dyspeptic symptoms has not been clearly demonstrated. We aimed to clarify the association of endoscopic appearances with Helicobacter pylori infection, histological severity of gastritis, and dyspeptic symptoms in a Japanese population. Methods We enrolled 87 dyspeptic and 93 nondyspeptic subjects in this study. All subjects underwent gastroscopy, and patients with active peptic ulcer disease, reflex esophagitis with erosion, polyps >1 cm, or cancer were excluded. Endoscopic appearances in patients with dyspeptic symptoms and in those without were assessed retrospectively on the basis of endoscopic images. The degree of atrophy by the Kimura-Takemoto classification system was also assessed. Helicobacter pylori infection status was examined by histology or antibody against H. pylori. Histological severity of inflammation and glandular atrophy in the antrum were assessed according to the updated Sydney System. The odds ratio (OR) and 95% confidence interval (CI) were calculated by logistic regression using the variables age, sex, H. pylori infection status, and all endoscopic appearances. Results The degree of atrophy tended to be lower among dyspeptic patients (P = 0.06). Among all endoscopic appearances, the liner redness (friability) in the antrum (OR = 3.90, 95% CI = 1.20−12.64) and duodenal ulcer (DU) scarring (OR = 3.41, 95% CI = 1.08−10.79) were independently associated with dyspepsia. Histological severity of inflammation and glandular atrophy were not associated with dyspeptic symptoms. Also, no correlation was found between endoscopic appearances and any of the different subgroups of dyspeptic symptoms. Patients with friability in the antrum and DU scar, which correlated with dyspeptic symptom showed some of communal symptoms such as epigastric pain, epigastric discomfort, hypochondriac pain, early satiation/postprandial fullness, and belching, but they differed considerably with respect to H. pylori positivity and the histological severity of gastritis. Conclusions Some endoscopic appearances such as friability in the antrum and DU scarring may be associated with dyspeptic symptoms, and endoscopic appearances may be useful markers to perform clinical implementation reflecting an individual’s pathophysiology of dyspeptic symptoms.  相似文献   
48.
Cyanobacteria possess a CO(2)-concentrating mechanism that involves active CO(2) uptake and HCO(3)(-) transport. For CO(2) uptake, we have identified two systems in the cyanobacterium Synechocystis sp. strain PCC 6803, one induced at low CO(2) and one constitutive. The low CO(2)-induced system showed higher maximal activity and higher affinity for CO(2) than the constitutive system. On the basis of speculation that separate NAD(P)H dehydrogenase complexes were essential for each of these systems, we reasoned that inactivation of one system would allow selection of mutants defective in the other. Thus, mutants unable to grow at pH 7.0 in air were recovered after transformation of a DeltandhD3 mutant with a transposon-bearing library. Four of them had tags within slr1302 (designated cupB), a homologue of sll1734 (cupA), which is cotranscribed with ndhF3 and ndhD3. The DeltacupB, DeltandhD4, and DeltandhF4 mutants showed CO(2)-uptake characteristics of the low CO(2)induced system observed in wild type. In contrast, mutants DeltacupA, DeltandhD3, and DeltandhF3 showed characteristics of the constitutive CO(2)-uptake system. Double mutants impaired in one component of each of the systems were unable to take up CO(2) and required high CO(2) for growth. Phylogenetic analysis indicated that the ndhD3/ndhD4-, ndhF3/ndhF4-, and cupA/cupB-type genes are present only in cyanobacteria. Most of the cyanobacterial strains studied possess the ndhD3/ndhD4-, ndhF3/ndhF4-, and cupA/cupB-type genes in pairs. Thus, the two types of NAD(P)H dehydrogenase complexes essential for low CO(2)-induced and constitutive CO(2)-uptake systems associated with the NdhD3/NdhF3/CupA-homologues and NdhD4/NdhF4/CupB-homologues, respectively, appear to be present in these cyanobacterial strains but not in other organisms.  相似文献   
49.
ObjectiveIrritability is an emotional stress symptom that causes or exacerbates dizziness. Antidepressants may be helpful for some conditions that are accompanied by irritability; however, they do not completely inhibit irritability. Yokukansan (YKS), a traditional Japanese herbal medicine, has been used for neurosis, insomnia, and children's irritability and night crying. The study investigated the efficacy of YKS in nystagmus in patients with chronic dizziness and irritability.MethodsTwenty-two cases with chronic dizziness and irritability were reviewed retrospectively. The patients were divided into two groups: control patients (0–7 days of treatment) and YKS-treated patients (YKS cases; >7 days of treatment). Dizziness before and during (after, in the controls) YKS treatment was evaluated by scoring the nystagmus intensity on a 5-point scale. The average scores were calculated within a maximum of 6 months before and during or after treatment. The normalized scores were also calculated. The optimal treatment regimen was calculated via receiver operating characteristic (ROC) curve analysis.ResultsThere were six control cases (1 male, 5 females; mean age: 59.5 years). There were 16 YKS cases (3 males, 13 females; mean age: 61.8 years). While the group mean nystagmus intensity scores significantly decreased from 1.18 to 0.73 in the YKS cases, it did not change in the control cases. The group mean of the normalized nystagmus intensity scores during treatment was 0.73 in the YKS cases. The results of the ROC curve analysis indicated the optimal cut-off period of the YKS treatment was 10 days.ConclusionThe oral administration of YKS for more than 10 days was optimal. The treatments with YKS could be a good option for the treatments of vertigo.  相似文献   
50.

Introduction

A number of studies have evaluated the effects of subcutaneous drainage during digestive surgery. All of the previous studies assessed the usefulness of active-suctioning drain, including two randomized controlled studies which found no benefit for the placement of active-suctioning drains in digestive surgery. The utility of passive drainage has not been evaluated previously. The purpose of this study was to evaluate the efficacy of subcutaneous passive drainage system for preventing surgical site infections during major colorectal surgery.

Patients and methods

A total of 263 patients who underwent major colorectal surgery were enrolled in this study. Patients were randomly assigned to receive subcutaneous passive drainage or no drainage. The primary outcome measured was the incidence of superficial surgical site infections. The secondary outcomes measured were the development of hematomas, seromas, and wound dehiscence.

Results

Finally, a total of 246 patients (124 underwent passive drainage, and 122 underwent no drainage) were included in the analysis after randomization. There was a significant difference in the incidence of superficial surgical site infections between patients assigned to the passive drainage and no drainage groups (3.2 % vs 9.8 %, respectively, P?=?0.041). There were no cases that developed a hematoma, seroma, or wound dehiscence in either group. A subgroup analysis revealed that male gender, age ≥75 years, diabetes mellitus, American Society of Anesthesiologists (ASA) status ≥2, blood loss ≥100 ml, and open access were factors that were associated with a beneficial effect of subcutaneous passive drainage.

Conclusions

Subcutaneous passive drainage provides benefits over no drainage in patients undergoing major colorectal surgery.  相似文献   
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