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81.
Objective: The aim of this study was to examine the expression of matriptase and survivin in breast carcinoma and correlate with clinicopathological parameters. Methods: Immunohistochemical analysis of matriptase and survivin were performed in tissue microarray slides of 290 cases, including 11 normal breast tissue; 27 fibrocystic disease; 17 fibroadenoma; 6 atypical ductal hyperplasia; 39 ductal carcinoma in situ, low grade (DCIS, low grade); 39 ductal carcinoma in situ, high grade (DCIS, high grade); 27 invasive ductal carcinoma, grade I (IDC, grade I); 78 invasive ductal carcinoma, grade II (IDC, grade II); and 46 invasive ductal carcinoma, grade III (IDC, grade III). Results: The average immunostaining scores of matriptase were 44.1 in normal breast tissue, 52.7 in fibrocystic disease, 76.5 in fibroadenoma, 81.7 in atypical ductal hyperplasia, 133.7 in low-grade DCIS, and 155.8 in high-grade DCIS. Among 151 breast IDC cases, the average immunostaining scores of matriptase were 172.7 in grade I, 211.7 in grade II, and 221.2 in grade III. Additionally, the average immunostaining scores of surviving also correlate with tumor grades and stages. Conclusions: Higher expressions of matriptase and survivin correlate significantly with clinicopathological parameters in breast cancer and the malignant potential in premalignant lesions. In addition, higher survivin expression had poorer prognosis of breast IDC cases.  相似文献   
82.
Several viral factors are associated with disease progression in hepatitis B virus (HBV) carriers. Compared with Taiwanese Han Chinese, Taiwanese aborigines have a higher prevalence of chronic HBV infection and a higher standardized mortality rate of chronic liver diseases but a lower standardized mortality rate of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether aboriginal Taiwanese HBV carriers have more favorable viral factors which reduce the risk for HCC than Han Chinese carriers. Blood samples from 3,488 HBV carriers (1,527 aborigines and 1,961 Han Chinese) were assayed for aminotransferases, hepatitis B e antigen (HBeAg), HBV DNA, and HBV genotype. Aboriginal HBV carriers had a lower HBeAg‐positive rate (5.3% vs. 10.2%, P < 0.0001) and a lower viral load of HBV DNA > 2,000 IU/ml (27.4% vs. 36.7%, P < 0.0001) but a higher rate of alcohol consumption (40.0% vs. 19.3%, P < 0.0001) than Han Chinese carriers. The prevalence of HBV genotype B in aboriginal carriers (92.7%) was significantly higher than that in Han Chinese carriers (72.7%) in all age groups (P < 0.05). In addition, patients with rare genotype D infections were clustered in a township in southern Taiwan. In conclusion, aboriginal Taiwanese HBV carriers have more favorable viral factors than Han Chinese carriers, which may be partly responsible for the lower standardized mortality rate of HCC in Taiwanese aborigines. J. Med. Virol. 83:1326–1331, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
83.

Background

Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.

Aim

This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.

Design and setting

Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.

Method

The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.

Results

The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.

Conclusion

The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care.  相似文献   
84.
Postherpetic neuralgia is the most common complication of herpes zoster which is caused by a reactivation of latent varicella zoster virus. The pathogenesis of postherpetic neuralgia may involve peripheral and central mechanisms. Reported risk factors for postherpetic neuralgia include female gender, old age, diminished cell-mediated immunity and nutritional deficiencies. Based on our clinical observation which revealed that peptic ulcer disease (PUD) is one of the common comorbidities in patients with postherpetic neuralgia, we hypothesize that herpes zoster patients with PUD may be at a greater risk for the development of postherpetic neuralgia due to their impaired cellular immunity and depressed nutritional status. Major causes of PUD include Helicobacter pylori infection and usage of ulcerogenic medications. Patients with H. pylori infection may develop T cell dysfunctions and nutritional deficiencies including vitamin C, iron, cobalamin, carotenes and alpha-tocopherol. Ulcerogenic medications such as nonsteroidal anti-inflammatory drugs and steroids have been found not only to be ulcerogenic but also immunosuppressive to T cells. In addition, usage of steroids and nonsteroidal anti-inflammatory drugs may cause deficiencies of alpha-tocopherol, carotenes, cobalamin, iron, zinc and vitamin C. Vitamin C, carotenes and alpha-tocopherol are anti-inflammatory and the major oxidant scavengers in the aqua phase and biomembranes. Deficiencies of these nutrients may induce dysregulated inflammation and oxidative damage leading to neuropathic pain in patients with herpes zoster. Furthermore, nutrient deficiencies including zinc, iron, cobalamin and vitamin C are associated with dysregulation of Ca(v)3.2 T-channels and N-methyl-d-aspartate receptors, upregulation of nitric oxide synthase, the increase of nitric oxide formation and dysfunction of central norepinephrine inhibitory pain pathway. Prospective cohort studies are suggested to test the hypothesis. We further propose that a follow-up study that contains two groups of herpes zoster patients, i.e., with or without gastroendoscopy-proven PUD, be conducted to determine their incidence of postherpetic neuralgia. In addition, despite of the high proportion of zoster patients having been treated with antiviral therapies, prevention and treatment of postherpetic neuralgia remain challenging in clinical practice. The potential risk of postherpetic neuralgia in zoster patients with PUD could mean that physicians need to pay more attention to the comorbidity - PUD in patients with herpes zoster and treat PUD earlier in order to prevent the development of postherpetic neuralgia.  相似文献   
85.
In response to aggravation by activated microglia, IL‐13 can significantly enhance ER stress induction, apoptosis, and death via reciprocal signaling through CCAAT/enhancer‐binding protein alpha (C/EBP‐α) and C/EBP‐beta (C/EBP‐β). This reciprocal signaling promotes neuronal survival. Since the induction of cyclooxygenase‐2 (COX‐2) and peroxisome proliferator‐activated receptor gamma/heme oxygenase 1 (PPAR‐γ/HO‐1) by IL‐13 plays a crucial role in the promotion of and protection from activated microglia, respectively; here, we investigated the role of IL‐13 in regulating C/EBPs in activated microglia and determined its correlation with neuronal function. The results revealed that IL‐13 significantly enhanced C/EBP‐α/COX‐2 expression and PGE2 production in LPS‐treated microglial cells. Paradoxically, IL‐13 abolished C/EBP‐β/PPAR‐γ/HO‐1 expression. IL‐13 also enhanced ER stress‐evoked calpain activation by promoting the association of C/EBP‐β and PPAR‐γ. SiRNA‐C/EBP‐α effectively reversed the combined LPS‐activated caspase‐12 activation and IL‐13‐induced apoptosis. In contrast, siRNA‐C/EBP‐β partially increased microglial cell apoptosis. By NeuN immunochemistry and CD11b staining, there was improvement in the loss of CA3 neuronal cells after intrahippocampal injection of IL‐13. This suggests that IL‐13‐enhanced PLA2 activity regulates COX‐2/PGE2 expression through C/EBP‐α activation. In parallel, ER stress‐related calpain downregulates the PPAR‐γ/HO‐1 pathway via C/EBP‐β and leads to aggravated death of activated microglia via IL‐13, thereby preventing cerebral inflammation and neuronal injury.  相似文献   
86.
Chromosome 11q13.5 containing RSF1 (HBXAP), a gene involved in chromatin remodelling, is amplified in several human cancers including ovarian carcinoma. Our previous studies demonstrated requirement of Rsf‐1 for cell survival in cancer cells, which contributed to tumour progression; however, its role in tumourigenesis has not yet been elucidated. In this study, we co‐immunoprecipitated proteins with Rsf‐1 followed by nanoelectrospray mass spectrometry and identified cyclin E1, besides SNF2H, as one of the major Rsf‐1 interacting proteins. Like RSF1, CCNE1 is frequently amplified in ovarian cancer, and both Rsf‐1 and cyclin E1 were found co‐up‐regulated in ovarian cancer tissues. Ectopic expression of Rsf‐1 and cyclin E1 in non‐tumourigenic TP53mut RK3E cells led to an increase in cellular proliferation and tumour formation by activating cyclin E1‐associated kinase (CDK2). Tumourigenesis was not detected if either cyclin E1 or Rsf‐1 was expressed, or they were expressed in a TP53wt background. Domain mapping showed that cyclin E1 interacted with the first 441 amino acids of Rsf‐1. Ectopic expression of this truncated domain significantly suppressed G1/S‐phase transition, cellular proliferation, and tumour formation of RK3E‐p53R175H/Rsf‐1/cyclin E1 cells. The above findings suggest that Rsf‐1 interacts and collaborates with cyclin E1 in neoplastic transformation and TP53 mutations are a prerequisite for tumour‐promoting functions of the RSF/cyclin E1 complex.  相似文献   
87.
Chen RM  Wu CH  Chang HC  Wu GJ  Lin YL  Sheu JR  Chen TL 《Anesthesiology》2003,98(5):1178-1185
BACKGROUND: Propofol is an intravenous anesthetic agent that may impair host defense system. The aim of this study was to evaluate the effects of propofol on macrophage functions and its possible mechanism. METHODS: Mouse macrophage-like Raw 264.7 cells were exposed to propofol, at 3, 30 (a clinically relevant concentration), and 300 microm. Cell viability, lactate dehydrogenase, and cell cycle were analyzed to determine the cellular toxicity of propofol to macrophages. After administration of propofol, chemotactic, phagocytic, and oxidative ability and interferon-gamma mRNA production were carried out to validate the potential effects of propofol on macrophage functions. Mitochondrial membrane potential and cellular adenosine triphosphate levels were also analyzed to evaluate the role of mitochondria in propofol-induced macrophage dysfunction. RESULTS: Exposure of macrophages to 3 and 30 microm propofol did not affect cell viability. When the administered concentration reached 300 microm, propofol would increase lactate dehydrogenase release, cause arrest of cell cycle in G1/S phase, and lead to cell death. In the 1-h-treated macrophages, propofol significantly reduced macrophage functions of chemotactic and oxidative ability in a concentration-dependent manner. However, the suppressive effects were partially or completely reversed after 6 and 24 h. Propofol could reduce phagocytic activities of macrophages in concentration- and time-dependent manners. Exposure of macrophages to lipopolysaccharide induced the mRNA of interferon-gamma, but the induction was significantly blocked by propofol. Propofol concentration-dependently decreased the membrane potential of macrophage mitochondria, but the effects were descended with time. The levels of cellular adenosine triphosphate in macrophages were also reduced by propofol. CONCLUSIONS: A clinically relevant concentration of propofol can suppress macrophage functions, possibly through inhibiting their mitochondrial membrane potential and adenosine triphosphate synthesis instead of direct cellular toxicity.  相似文献   
88.
Methods to reliably measure tissue oxygenation in situ are currently lacking. We have developed a vertically oriented, dorsal, bipedicle flap model that is easy to perform, reliably reproduces tissue ischemia, eliminates craniocaudal variation, and is amenable to studying therapeutic modalities. The effect of narrowing this flap on tissue oxygenation measured with Licox electrodes has previously been presented. In this study we utilize in situ EPR spectroscopy to demonstrate the oxygen gradient in the flap as a function of flap width and placement of a silicone sheet directly under the flap. The effect of wound healing over a 2 week period is demonstrated. Twenty four, 300 gm male Sprague‐Dawley rats underwent creation of the bipedicle flap according to the following groups: 2.5 cm flap with silicone, 2.0 cm flap without silicone, 2.0 cm flap with silicone. Each group of 6 animals was injected with EMS char at 2 cm intervals along the flap and one injection in the control, non‐ischemic tissue. A 4th group underwent 2.0 cm flaps with silicone and use of lithium phthalocyanin as the paramagnetic material. Wound measurements and EPR spectroscopy were performed on days 3, 7, 10 and 14. On day 14, after EPR measurements, the animals were sacrificed and their wounds excised. One flap and one control wound were preserved for histologic analysis, the other flap and control wounds were prepared for lactate measurements. EPR spectroscopy demonstrated a gradient of oxygen that was lowest in the center of the flap and greatest at either end. Changes in the oxygen gradient correlated with narrowing and placement of the intervening silicone sheet. This new technology has never been utilized in an animal model of impaired wound healing. Comparison of recently developed paramagnetic materials for optimal tissue oxygen and free radical measurements will be presented.  相似文献   
89.
The effect of changes in plasma non-esterified fatty acid concentration (NEFA) on plasma glucose concentration, hepatic glucose production (Ra), and glucose disposal (Rd) rates was determined in 14 patients with Type 2 diabetes. Seven patients had relatively mild fasting hyperglycaemia (less than 10.0 mmol l-1), whereas the remaining seven had relatively severe fasting hyperglycaemia (greater than 14.0 mmol l-1). Each patient was infused from 2000 to 0800 h with 3-3H-glucose on two occasions, with or without neutral fat emulsion and heparin (mild hyperglycaemia group), or with or without nicotinic acid (severe hyperglycaemia group). Plasma NEFA concentration increased from 0.33 +/- 0.06 (+/- SE) to 4.78 +/- 0.42 mmol l-1 in response to the lipid and heparin infusion, but plasma glucose concentration (7.8 +/- 0.7 vs 7.4 +/- 0.8 mmol l-1), Ra (0.44 +/- 0.02 vs 0.46 +/- 0.02 mmol m-2 min-1), and Rd (0.42 +/- 0.02 vs 0.46 +/- 0.02 mmol m-2 min-1) were unchanged. Nicotinic acid decreased plasma NEFA concentration from 0.54 +/- 0.15 to 0.23 +/- 0.08 mmol l-1, but plasma glucose (15.0 +/- 1.0 vs 15.5 +/- 1.4 mmol l-1), Ra (0.74 +/- 0.07 vs 0.68 +/- 0.07 mmol m-2 min-1), and Rd (0.73 +/- 0.07 vs 0.68 +/- 0.07 mmol m-2 min-1) were unchanged. The results indicate that acute changes in plasma NEFA concentration did not lead to any change in overnight glucose production or disposal rates.  相似文献   
90.
Serum hepatitis B virus (HBV) DNA was assayed using polymerase chain reaction, in 107 HBsAg-negative normal Chinese subjects. The results showed that eight subjects (7.5%) had HBV DNA. In the subgroup with antibody to hepatitis B surface antigen (anti-HBs) and to hepatitis B core antigen (anti-HBc), 7.3% (5/68) were positive for HBV DNA; HBV DNA was not detected in six individuals with anti-HBs only and in nine with anti-HBc only. In four persons with anti-HBc and anti-HBe, one had HBV DNA. In 20 subjects negative for all hepatitis B serological markers, two (10%) were found to have HBV DNA. This study indicates that serological markers are not adequate to rule out HBV infection, and it further implies that present blood donor screening methods may need improving.  相似文献   
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