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BACKGROUND AND STUDY AIMS: The purpose of the current study was to investigate the role of beta-catenin, E-cadherin and P-cadherin in colorectal carcinogenesis using tissue array method. PATIENTS AND METHODS: Core tissue biopsies were taken from paraffin-embedded tissue blocks of 167 cases including 26 normal mucosae (NM), 99 colorectal polyps (10 hyperplastic polyps (HP), 8 traditional serrated (TSA), 17 tubular (TA), 37 tubulovillous (TVA), and 27 villous adenomas (VA)), 14 adenomas with intramucosal carcinoma (ACA), and 28 colorectal cancers (CCA). Immunohistochemistry was performed using antibodies to beta-catenin, E-cadherin, and P-cadherin. Distribution of positivity was assessed using percentage expression while an arbitrary grading scale was used for staining intensity. RESULTS: beta-catenin expression was cytoplasmic, membranous, and nuclear. Both E-cadherin and P-cadherin expressions were confined to cytoplasmic-membranous compartments. Membranous expression of beta-catenin significantly decreased in CCA (p < 0.01). Nuclear beta-catenin expression significantly increased in close correlation with neoplastic sequence reaching its highest expression in ACA and CCA (p < 0.001). Polyps with intraepithelial neoplasia (IEN) showed significantly higher nuclear beta-catenin expression in parallel with increasing grades of IEN (p < 0.001). E-cadherin and P-cadherin expression increased in polyps, whereas a significant decrease in their expression was observed in CCA (p < 0.001) while E-cadherin expression significantly increased in CCA compared to NM (p < 0.001), no such difference was observed in P-cadherin expression. CONCLUSIONS: Nuclear beta-catenin expression correlating with the grade of IEN in polyps and carcinomas supports its role in colorectal carcinogenesis. E-cadherin and P-cadherin expressions in adenomas suggest that these molecules might have role in adenoma formation though not necessarily be involved in neoplastic progression.  相似文献   
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We tested dexmedetomidine, an alpha2 agonist, for its ability to decrease heart rate, arterial blood pressure, and neuroendocrinal responses to skull-pin head-holder application during craniotomy. In a randomized, double-blinded, placebo-controlled study, 40 patients undergoing craniotomy with attachment of a pin head-holder were randomly assigned to one of 2 equal groups. The placebo group received saline, whereas the treatment group (DEX group) received a single bolus dose of dexmedetomidine (1 microg/kg) intravenously over 10 minutes before induction of anesthesia. Arterial blood pressure, heart rate, and sequential concentrations of circulating cortisol, prolactin, insulin, and blood glucose were measured. Relative to baseline and the other group, arterial blood pressure and heart rate decreased significantly after the administration of dexmedetomidine through skull pinning (P<0.05). In the placebo group, patients' heart rate and arterial blood pressure measures increased at 1 and 5 minutes after skull-pin insertion, compared with baseline and the DEX group (P<0.05). In both groups, plasma cortisol, prolactin, and blood glucose increased significantly relative to baseline after skull-pin insertion. However, the values were significantly higher in the placebo group compared with the DEX group (P<0.05). Although insulin levels were not significantly altered in the DEX group, the plasma concentrations of insulin decreased significantly after pin insertion in the placebo group. Our results suggested that, a single bolus dose of dexmedetomidine before induction of anesthesia attenuated the hemodynamic and neuroendocrinal responses to skull-pin insertion in patients undergoing craniotomy.  相似文献   
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Paracetamol, a centrally acting inhibitor of cyclooxygenase, has less gastrointestinal and platelet-inhibiting side effects and is clinically better tolerated than nonsteroidal anti-inflammatory drugs. Therefore, it will be ideally suited for postoperative pain relief. In this prospective, double-blind, randomized, placebo-controlled study, we evaluated the analgesic efficacy, opioid-sparing effect and effects on opioid-related adverse effects of intravenous (IV) paracetamol in combination with IV morphine after lumbar laminectomy and discectomy. Forty patients were divided into 2 groups (n=20 each) to receive either paracetamol 1 g (group 1) or 0.9% NaCl 100 ml (group 2) at the end of the operation and at 6-hour intervals over 24 hours. IV patient-controlled analgesia with morphine was used as a rescue analgesic in both groups. Pain was evaluated at rest and on movement at the 1st, 2nd, 4th, 6th, 12th, 18th, and 24th hours using a visual analog scale. Hemodynamic parameters, morphine usage, patient satisfaction, and probable side effects were also evaluated. Pain scores at rest and on movement at the 12th, 18th, and 24th hours were significantly lower in group 1 (P<0.001). Morphine consumption was not statistically significantly different between the groups (P>0.05). Vomiting in group 2 was significantly higher (P=0.027). Significantly more patients in the paracetamol group rated their pain management as excellent (45% vs. 5%). Although repeated IV paracetamol usage after lumbar laminectomy and discectomy did not demonstrate a significant opioid-sparing effect, it did decrease visual analog scale scores at certain evaluation times and incidence of vomiting and increase patient satisfaction.  相似文献   
55.
This study is designed to determine the placental zinc (Zn) and cadmium (Cd) levels in mothers who were smokers, mothers who were thought to be exposed to air pollution, and mothers who were non-smokers and to investigate the relationship between the expression of placental metallothionein (MT) binding these metals and blood progesterone level. Placental Zn and Cd levels were measured by atomic absorption spectrometry. Presence of placental MT was determined immunohistochemically. Placental changes were examined by light microscope after H&E and PAS staining. Immunohistochemical MT staining of syncytiotrophoblastic and villous interstitial cells were scored as positive or negative. Among the 92 mothers included in the study, 33 were smokers (Group I), 29 had been exposed to air pollution (Group II) and 30 were non-smoker rural residents who had never been exposed to air pollution (Group III). Mean off-spring birth weight of 3198.62+/-380.01 g and mean placenta weight of 561.38+/-111.55 g of Group II were lower when compared with those of other two groups. In Group I, mean placental Cd and Zn were 0.063+/-0.022 microg/g and 39.84+/-15.5 microg/g, respectively, being higher than in other groups. In Group II, mean placental Cd and Zn levels were higher than those of Group III. Blood progesterone levels of subjects in Group I (121 ng/ml) were the lowest of all groups. While the mean count of villi was the highest in Group III; the highest mean count of syncytial knots was in Group II. Thickening of vasculo-syncytial membrane was most prominent in Group I. Similarly, MT staining was positive and very dense in 72.7% (24/33) of cases in Group I (p相似文献   
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OBJECTIVE: The objective of this study is to investigate the presence of viral DNAs of HSV-1, HSV-2, HHV-6, HHV-8, and CMV in hippocampus of the patients with mesial temporal lobe epilepsy (MTLE) syndrome. METHODS: Pathological specimens were obtained from 33 patients with MTLE undergone temporal lobectomy with amygdalo-hippocampectomy due to intractable seizures. Autopsy materials from the hippocampus of 7 patients without neurological disease were used as controls. The data was also correlated with the clinical history of patients including febrile convulsions, age, and history of CNS infections. Real-time polymerase chain reaction method was performed for detection of DNAs of these viruses. RESULTS: HHV-6, HSV-1 and HHV-8 were detected in the hippocampus of 3, 2 and 1 patients with MTLE respectively. None of the hippocampus of patients with MTLE was positive for DNA of HSV-2 and/or CMV. Three patients with positive HHV-6 DNAs had febrile convulsions and family history for epilepsy. None of our control specimens showed PCR positivity to any of the 5 tested viruses. CONCLUSIONS: Our study is the first to report the presence of HHV-8 viral genome in the brain tissue of patient with MTLE. Viral DNAs were detected in a total of 18% of the patients in this study; we can conclude that activity of the latent virus in patients with hippocampal sclerosis should be more extensively studied to establish its role in active infection.  相似文献   
58.
Objective The aim of this study was to investigate the role of adhesion molecules in epididymal injury induced by ischemia-reperfusion (I-R) in the rats. Study design About 20 male Sprague-Dawley rats were separated into two groups. A sham operation was performed in group 1 (control). In group 2 (I-R), following 6 h of unilateral spermatic cord torsion, 1-h detorsion of the testis was performed. Then, epididymides were removed to measure the tissue levels of malondialdehyde (MDA) and to make histological examination. Results Malondialdehyde values increased in group 2. In group 2, the rats demonstrated significant disorganization of the epithelium and loss of microvilli in the epididymal tissue. No abnormal microscopic findings of the epididymis of the rats in the control group. The tenascin expression in the interstitial area of the epididymis was intense in group 2. Intercellular adhesion molecule-1 (ICAM-1) expression by intense brown staining was seen along the basement membrane in epididymal tissue from I-R group rats. The microvillus sites of the epithelia in I-R group were stained mildly by lectin. Conclusion The increased expression of adhesion molecules found in epididymal injury induced during of postischemic reperfusion may implicate importance of inflammatory infiltration.  相似文献   
59.
OBJECTIVE: To evaluate the WeeFIM instrument's reliability and internal construct validity for the Turkish child population. DESIGN: License was taken from UDSmr to use the WeeFIM instrument. For the reliability and validity studies of the Turkish translation of the WeeFIM instrument, 573 Turkish nondisabled children were included in the study. The reliability of the instrument was assessed by Cronbach's alpha coefficient, intraclass correlation coefficient (ICC), and test-retest reliability. Internal construct validity was assessed by both using Rasch unidimensional measurement model and testing for differential item functioning for age and gender. RESULTS: Cronbach alpha value was 0.99 for motor WeeFIM rating and 0.99 for cognitive WeeFIM rating. ICC was 0.81 for motor WeeFIM rating and 0.92 for cognitive WeeFIM rating. The internal construct validity of the Turkish translation of the WeeFIM instrument was confirmed by excellent fit to the Rasch measurement model. Two subscales were found from the principal component analysis of standardized residual correlation for items. Among the items, bowel management, bladder management, eating, and comprehension showed considerable levels of misfit. CONCLUSIONS: The Turkish translation of the WeeFIM instrument is valid, reliable, and practical for the Turkish child population. Further studies are required to determine the cross-cultural validity of the instrument.  相似文献   
60.
Endobronchial metastases: a clinicopathological analysis   总被引:1,自引:0,他引:1  
OBJECTIVE: It is important to distinguish endobronchial metastases (EBM) from both primary lung cancers and benign lesions, as treatment will differ. The clinicopathological characteristics of EBM cases were documented to see whether any distinguishing features exist. METHODOLOGY: Histological cases diagnosed as EBM in the pathology laboratory of a tertiary hospital were re-evaluated. Symptoms, primary tumour sites, recurrence interval, radiological and bronchoscopic features, and histopathological properties were assessed. RESULTS: There were 18 cases (eight female, 10 male) with EBM. All were diagnosed by bronchoscopic bronchial biopsy. The primary tumour sites were: colorectal (4), breast (3), renal (3), lymphoma (3), rhabdomyosarcoma (2), bladder (1), thyroid (1) and malignant melanoma (1). The mean time from the diagnosis of the primary tumour to their presentation was 3.89+/-1.09 (range, 0--19) years. In five patients, EBM was diagnosed synchronously with their extra pulmonary primary tumour. Two had other metastatic sites. Haemoptysis and cough were the more common symptoms. Interestingly, three patients were asymptomatic. There was no predilection for a particular airway segment to be involved but a predilection for the upper lobe existed. Endoscopic appearance was polypoid in 10 cases and mucosal infiltration in the remainder. Histopathological examination revealed epithelial tissue at the surface of the tumour in nine cases and four of these were metaplastic. In all but one there was inflammation, mainly lymphocytic. Necrosis was present in 10 cases and bleeding was seen in four. There were no statistically significant differences between the level of lymphocytic inflammation and other clinicopathological parameters. CONCLUSION: EBM is a rare condition that can be synchronous or occur late. Surprisingly, it can be asymptomatic. It is usually found in the upper lobes. Lymphocytic inflammation is a common histopathological finding. There is need for further studies to clarify the clinical importance of EBM.  相似文献   
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