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991.
AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies. Microscopic features of ITB and CD were reviewed, and eight pathologic parameters were evaluated. Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test, respectively. PCR assays were done using two commercial kits: kit detected IS6110 and MPB64, and kit detected IS6110 only; a manual in-house PCR method was also performed on formalin-fixed, paraffin-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000), giant cells (P = 0.015), caseation necrosis (P = 0.003), confluent granulomas (P = 0.001), discrete granulomas (P = 0.000), and granulomas with lymphoid cuffs (P = 0.037). However, 29 cases (52.7%) of ITB showed less than five kinds of pathologic parameters, resulting in confusion with CD. The sensitivities and specificities of the TB-PCR test by kit , kit , and the in-house PCR method were 88.9% and 100%, 88.9% and 100%, and 66.7% and 100% in positive and negative controls, respectively. The PCR test done on endoscopic biopsy specimens of ITB and CD were significantly different with kit (P = 0.000) and kit (P = 0.000). The sensitivities and specificities of TB-PCR were 45.5% and 88.1%, 36.4% and 100%, and 5.8% and 100%, for kit and kit and in-house PCR method on endoscopic biopsy specimens. Among the 29 cases of histopathologically confusing CD, 10 cases assayed using kit and 6 cases assayed using kit were TB-PCR positive. A combination of histologic findings and TB-PCR testing led to an increase of diagnostic sensitivity and the increase (from 47.3% to 58.2) was statistically significant with kit (P = 0.000).CONCLUSION: The TB-PCR test combined with histopathologic factors appears to be a helpful technique in formulating the differential diagnosis of ITB and CD in endoscopic biopsy samples.  相似文献   
992.
993.
Objectives: To analyze the characteristics and the prognostic significance of chromophobe renal cell carcinomas (chRCC). Methods: Data about 2981 patients with non‐metastatic renal cell carcinomas (RCC) at the time of surgery were retrospectively collected from 26 institutions between 1998 and 2008. All patients had undergone partial or radical nephrectomies. Of the 2981 patients, 2602 patients with conventional RCC (cRCC) and 148 with chRCC were studied. Clinical and pathological parameters were determined in all patients. Recurrence‐free survival (RFS) and cancer‐specific survival (CSS) were assessed. Results: Patients with chRCC differed significantly from those with cRCC on the following parameters: younger age (P = 0.026), greater female ratio (P < 0.001), and larger tumor diameter (P < 0.001). Both groups were alike with respect to body mass index (P = 0.943), Eastern Cooperative Oncology Group performance status (P = 0.163), T stage (P = 0.375), and Fuhrman's grade (P = 0.134). The 5‐year RFS rates in patients with chRCC and cRCC were 82.7% and 83.3%, respectively (P = 0.762). The 5‐year CSS rates in patients with chRCC and cRCC were 88.8% and 92.2%, respectively (P = 0.980). Both groups showed equivalent oncological outcomes in terms of RFS and CSS for cases stratified by T stage and Fuhrman's grade. In multivariate analysis, the histological subtype was not retained as an independent prognostic variable (RFS: P = 0.893; CSS: P = 0.729). Conclusions: Despite being significantly different from cRCC in terms of several clinical and pathological parameters, chRCC shows equivalent oncological outcomes.  相似文献   
994.
Angiotensin converting enzyme (ACE) inhibition is a common therapeutic modality in the treatment of autosomal recessive polycystic kidney disease (ARPKD). This study was designed to investigate whether chronic inhibition of ACE would have a therapeutic effect in attenuating the progression of renal cystogenesis in an orthologous rat model of ARPKD, the polycystic kidney (PCK) rat. Lisinopril (3 mg/kg per day) was administered orally for a period of 12 weeks, beginning at post-natal week 4. Lisinopril treatment resulted in an ∼30% improvement in the collecting duct cystic indices (CT CI) of PCK animals. Activation of extracellular signal-regulated kinase 1 (ERK1) and 2 (ERK2), proliferative signaling markers, and proliferating cell nuclear antigen (PCNA), an end-point marker for proliferation, was reduced following chronic treatment with lisinopril compared to that in vehicle-treated PCK rats. To assess whether apoptotic pathways were altered due to chronic ACE inhibition, we examined p38 mitogen activated protein kinase (MAPK) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), which are markers of apoptotic signaling cascades. p38 MAPK was significantly reduced (P < 0.0001) following chronic treatment with lisinopril, but no change in the activation of SAPK/JNK could be detected by immunoblot analysis. Lisinopril treatment resulted in a significant reduction (P < 0.01) in cleaved caspase-7 levels, but not caspase-3 activity, in PCK rat kidneys compared to the vehicle-treated PCK rat kidneys. Proteinuria was completely ameliorated in the presence of chronic ACE inhibition in the lisinopril-treated rats compared with the vehicle-treated PCK rats. In all, these findings demonstrated that chronic ACE inhibition can beneficially alter proliferative and apoptotic pathways to promote therapeutic reductions in renal cyst development in ARPKD.  相似文献   
995.
996.
Cytomegalovirus (CMV) infection is not only a common complication after liver transplantation but also a significant contributing factor to morbidity and mortality. We investigated whether preemptive therapy can prevent CMV syndrome or tissue-invasive CMV disease in an endemic area. Preemptive therapy was initiated when more than 10 positive CMV pp65 antigen-positive cells per 400,000 white blood cells were detected, regardless of clinical manifestations. Intravenous ganciclovir as preemptive therapy was administered daily for 10 to 14 days until negative results were achieved. The incidence of initial CMV antigenemia and CMV syndrome during the posttransplantation period was 49.7% (353/710) and 5.2% (37/710), respectively. One hundred eight-two patients (51.6%) received ganciclovir as preemptive therapy. Patients with CMV antigenemia who received preemptive therapy had high Model for End-Stage Liver Disease score, repeat operation, renal dysfunction, infection, low hemoglobin concentration, low platelet count, low albumin concentration, high international normalized ratio, high total bilirubin value, high aspartate transaminase concentration, and high CMV peak titer. Cytomegalovirus syndrome and tissue-invasive CMV disease were more common in these patients. The survival curve in patients without CMV syndrome was better than that in those with CMV syndrome (P = .000). Patients with more than 10 pp65 antigen-positive cells per 400,000 white blood cells should be treated aggressively with an antiviral agent as preemptive therapy because CMV infection is common in CMV-endemic areas and patients with CMV syndrome demonstrate poor survival rates.  相似文献   
997.
Porcine organs are valuable candidate materials for xenotransplantation to humans. Long-term maintenance of well functioning transplants is a prerequisite for success. Transplanted organs may be damaged by immune reactions or by infectious agents in hosts. Human herpesviruses (HHVs) establish life-long latency in humans after a primary infection. They can be reactivated with various stimuli, including immunosuppression. This study was performed to verify the infectivity of some HHVs toward porcine cells. PK-15 cells infected with HHV-1 and HHV-2 showed cytopathology from 1 day after infection. Immunofluorescent (IF) staining of HHV-1- and HHV-2-infected PK-15 cells with respective antibodies demonstrated the expression of the respective viral antigens. Permissiveness of PK-15 to HHV-1 and -2 was confirmed by an infection test on Vero cells. Islet cells infected with HHV-5 showed no gross morphologic changes during the experimental course. A limited portion of islet cells reacted only to anti-IE1 and anti-IE2, but not to anti-UL44 or anti-gB antibody by IF staining, whereas a small portion of endothelial cells reacted to anti-IEs and anti-UL44, but not to anti-gB antibody. HHV-1 and -2 can permissively infect porcine cells, but HHV-5 infects a small proportion of cells with limited viral protein expression. HHV-4 could not transform peripheral blood mononuclear cells from miniature pigs. Collectively, because some HHVs can infect and damage porcine cells or impair their functions, HHVs should be cautiously monitored and controlled in humans when porcine cells or organs are transplanted to human beings.  相似文献   
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Background  

This study aimed to compare the surgical outcome and long-term survival between simultaneous and delayed resection of liver metastases from colorectal cancer (LM), and to identify the factors influencing hepatic disease-free survival in patients with synchronous LM.  相似文献   
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