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41.
Expression of inducible nitric oxide synthase and cyclooxygenase-2 in pancreatic adenocarcinoma: Correlation with microvessel density 总被引:6,自引:0,他引:6
Kasper HU Wolf H Drebber U Wolf HK Kern MA 《World journal of gastroenterology : WJG》2004,10(13):1918-1922
AIM: Cyclooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins. Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible isoforms. The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis, tumorigenesis and inflammatory processes. This study was to clarify their role in pancreatic adenocarcinomas. METHODS: We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocarcinomas of different grade and stage. The results were compared with microvessel density and clinicopathological data. RESULTS: Twenty-one (52.5%) of the cases showed iNOS expression, 15 (37.5%) of the cases were positive for COX-2. The immunoreaction was heterogeneously distributed within the tumors. Staining intensity was different between the tumors. No correlation between iNOS and COX-2 expression was seen. There was no relationship with microvessel density. However, iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression. There was no correlation with other clinicopathological data. CONCLUSION: Approximately half of the cases expressed iNOS and COX-2. These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas. Due to a low prevalence of COX-2 expression, chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success. 相似文献
42.
Luigi Villa Thilo Krüger Claudia Seikrit Anja S. Mühlfeld Uta Kunter Cornelius Werner Michael Kleines Maximilian Schulze-Hagen Michael Dreher Alexander Kersten Nikolaus Marx Jürgen Floege Thomas Rauen Gerald S. Braun 《Medicine》2021,100(10)
Chronic renal replacement therapy by either a kidney transplant (KTX) or hemodialysis (HD) predisposes patients to an increased risk for adverse outcomes of COVID-19. However, details on this interaction remain incomplete. To provide further characterization, we undertook a retrospective observational cohort analysis of the majority of the hemodialysis and renal transplant population affected by the first regional outbreak of severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) in Germany. In a region of 250,000 inhabitants we identified a total of 21 cases with SARS-CoV-2 among 100 KTX and 260 HD patients, that is, 7 KTX with COVID-19, 14 HD with COVID-19, and 3 HD with asymptomatic carrier status. As a first observation, KTX recipients exhibited trends for a higher mortality (43 vs 18%) and a higher proportion of acute respiratory distress syndrome (ARDS) (57 vs 27%) when compared to their HD counterparts. As a novel finding, development of ARDS was significantly associated with the time spent on previous renal replacement therapy (RRT), defined as the composite of dialysis time and time on the transplant (non-ARDS 4.3 vs ARDS 10.6 years, P = .016). Multivariate logistic regression analysis showed an OR of 1.7 per year of RRT. The association remained robust when analysis was confined to KTX patients (5.1 vs 13.2 years, P = .002) or when correlating the time spent on a renal transplant alone (P = .038). Similarly, longer RRT correlated with death vs survival (P = .0002). In conclusion our data suggest renal replacement vintage as a novel risk factor for COVID-19-associated ARDS and death. The findings should be validated by larger cohorts. 相似文献
43.
Uta Lehmann 《BMC health services research》2015,16(1):1-9
Community-based strategies that foster frequent contact between caregivers of children under five and provide credible sources of health information are essential to improve child survival. Care Groups are a community-based implementation strategy for the delivery of social and behavior change interventions. This study assessed if supervision of Care Group activities by Ministry of Health (MOH) personnel could achieve the same child health outcomes as supervision provided by specialized non-governmental organization (NGO) staff. The study was a pretest-posttest quasi-experimental design implemented in Burundi. A total of 45 MOH-led Care Groups with 478 Care Group Volunteers (CGVs) were established in the intervention area; and 50 NGO-led Care Groups with 509 CGVs were formed in the comparison area. Data were collected from 593 and 700 mothers of children 0-23 months at baseline and endline, respectively. Pearson’s chi-squared test and difference-in-difference analysis assessed changes in 40 child health and nutrition outcomes. A qualitative process evaluation was also conducted midway through the study. The MOH-led Care Group model performed at least as well as the NGO-led model in achieving specific child health and nutrition outcomes. Mothers of children 0-23 months in the intervention and comparison sites reported similar levels of knowledge and practices for 38 of 40 dependent variables measured in the study, and these results remained unchanged after accounting for differences in the indicator values at baseline. Process monitoring data confirmed that the MOH-led Care Group model and the NGO-led Care Group model were implemented with similar intervention strength. The study demonstrated that behavior change interventions traditionally led by NGOs can be implemented through the existing MOH systems and achieve similar results, thereby increasing the potential for sustainable child health outcomes. Future research on the MOH-led Care Group model is required to systematically document all inputs and monetary costs borne by the MOH to implement the model. 相似文献
44.
Adiponectin is independently associated with insulin sensitivity in women with polycystic ovary syndrome 总被引:6,自引:0,他引:6
Spranger J Möhlig M Wegewitz U Ristow M Pfeiffer AF Schill T Schlösser HW Brabant G Schöfl C 《Clinical endocrinology》2004,61(6):738-746
OBJECTIVE: The polycystic ovary syndrome (PCOS) is associated with obesity and insulin resistance predisposing to diabetes mellitus type 2 and atherosclerosis. Adiponectin is a recently discovered adipocytokine with insulin-sensitizing and putative antiatherosclerotic properties. The aim of the study was to elucidate determinants of circulating adiponectin levels and to investigate the potential role of adiponectin in insulin resistance in PCOS women. PATIENTS AND MEASUREMENTS: Plasma adiponectin and parameters of obesity, insulin resistance and hyperandrogenism were measured In 62 women with PCOS and in 35 healthy female controls. RESULTS: Both in PCOS and controls, adiponectin levels were lower in overweight or obese women than in normal-weight women, without any difference between PCOS and controls after adjustment for body mass index (BMI). In PCOS and in controls there was a significant correlation of adiponectin with BMI (r = -0.516, P < 0.001), fasting insulin (r = -0.404, P < 0.001), homeostasis model sensitivity (HOMA %S) (r = -0.424, P < 0.001) and testosterone (r = -0.279, P < 0.01), but no correlation with androstenedione (r = -0.112, P = 0.325), 17-OH-progesterone (r =-0.031, P = 0.784) or the LH/FSH ratio (r =-0.033, P = 0.753). Multiple linear regression analysis revealed that BMI and HOMA %S but not testosterone were independently associated with adiponectin plasma levels, explaining 16% (BMI) and 13% (HOMA %S) of the variability of adiponectin, respectively. In PCOS patients insulin sensitivity, as indicated by continuous infusion of glucose with model assessment (CIGMA %S) was significantly correlated with adiponectin (r = 0.55; P < 0.001), BMI (r =-0.575; P < 0.001), waist-to-hip ratio (WHR) (r =-0.48; P = 0.001), body fat mass assessed by dual-energy X-ray-absorptiometry (DEXA) [Dexa-fat (total) (r = -0.61; P < 0.001) and Dexa-fat (trunk) (r = -0.59; P < 0.001)] and with testosterone (r = -0.42; P = 0.001). Multiple linear regression analysis demonstrated that markers of obesity such as BMI, total or truncal fat mass, age and adiponectin were independently associated with CIGMA %S, and that circulating adiponectin accounted for about 18% of the degree of insulin resistance in PCOS. By contrast, testosterone was not a significant factor, suggesting that PCOS per se did not affect insulin sensitivity independent from obesity, age and adiponectin. Metformin treatment for 6 months in insulin-resistant PCOS women (n = 9) had no effect on plasma adiponectin (P = 0.59) despite significant loss of weight and fat mass and improvement in hyperandrogenaemia. CONCLUSIONS: PCOS per se is not associated with decreased levels of plasma adiponectin. However, circulating adiponectin is independently associated with the degree of insulin resistance in PCOS women and may contribute to the development and/or maintenance of insulin resistance independent from adiposity. 相似文献
45.
Dieter Schröder Matthias Ratke Uta Christina Bauer Ingrid Klöting Brigitte Ziegler Siegfried Schmidt 《Autoimmunity》2013,46(2):143-153
Normoglycemic diabetes-prone BB/OK rats aged 33, 45 or 75 days were subjected to prophylactic insulin treatment by means of a single subcutaneous application of a sustained release insulin implant. The single application of a sustained release insulin implant decreased the incidence of diabetes or delayed the onset of the disease in BB/OK rats of all treatment groups. Prophylactic insulin administration caused a transient hypoglycemic period accompanied by an inhibition of glucose stimulated insulin secretion and a decrease of the insulin content of Langerhans' islets as detectable in vitro . Compared to islets of normoglycemic controls pancreatic islets isolated from hypoglycemic BB/OK rats within 7-21 days after the insulin application at 45 days of age displayed a decreased susceptibility of the cells to complement-dependent cytotoxicity of the monoclonal islet cell surface antibody (ICSA) K14D10 but not to the cytotoxic effect of the ICSA M3aG8. The appearance of complement-dependent antibody-mediated cytotoxicity to islet cells and pancreatic exocrine cells in serum regarded as a sign of immune dysregulation in BB/OK rats seems not to be affected by insulin prophylaxis and was detectable during hypoglycemia as well as in the subsequent normoglycemic state. In conclusion, BB/OK rats of different age can be protected from diabetes by a single application of a sustained release insulin implant. Insulin and/or hypoglycemia seem to influence the expression of cell surface antigens, thus render the islets of Langerhans less vulnerable to immune cytolysis, whereas the appearance of humoral immunological abnormalites is not affected. 相似文献
46.
Anna Uta Rysop Lea‐Maria Schmitt Jonas Obleser Gesa Hartwigsen 《Human brain mapping》2021,42(1):110-127
When speech intelligibility is reduced, listeners exploit constraints posed by semantic context to facilitate comprehension. The left angular gyrus (AG) has been argued to drive this semantic predictability gain. Taking a network perspective, we ask how the connectivity within language‐specific and domain‐general networks flexibly adapts to the predictability and intelligibility of speech. During continuous functional magnetic resonance imaging (fMRI), participants repeated sentences, which varied in semantic predictability of the final word and in acoustic intelligibility. At the neural level, highly predictable sentences led to stronger activation of left‐hemispheric semantic regions including subregions of the AG (PGa, PGp) and posterior middle temporal gyrus when speech became more intelligible. The behavioural predictability gain of single participants mapped onto the same regions but was complemented by increased activity in frontal and medial regions. Effective connectivity from PGa to PGp increased for more intelligible sentences. In contrast, inhibitory influence from pre‐supplementary motor area to left insula was strongest when predictability and intelligibility of sentences were either lowest or highest. This interactive effect was negatively correlated with the behavioural predictability gain. Together, these results suggest that successful comprehension in noisy listening conditions relies on an interplay of semantic regions and concurrent inhibition of cognitive control regions when semantic cues are available. 相似文献
47.
Lukas Meyer Michael Schnfeld Matthias Bechstein Uta Hanning Bastian Cheng Gtz Thomalla Gerhard Schn Andre Kemmling Jens Fiehler Gabriel Broocks 《Journal of cerebral blood flow and metabolism》2021,41(1):45
The effect of age on lesion pathophysiology in the context of thrombectomy has been poorly investigated. We aimed to investigate the impact of age on ischemic lesion water homeostasis measured with net water uptake (NWU) within a multicenter cohort of patients receiving thrombectomy for anterior circulation large vessel occlusion (LVO) stroke. Lesion-NWU was quantified in multimodal CT on admission and 24 h for calculating Δ-NWU as their difference. The impact of age and procedural parameters on Δ-NWU was analyzed. Multivariable regression analysis was performed to identify significant predictors for Δ-NWU. Two hundred and four patients with anterior circulation stroke were included in the retrospective analysis. Comparison of younger and elderly patients showed no significant differences in NWU on admission but significantly higher Δ-NWU (p = 0.005) on follow-up CT in younger patients. In multivariable regression analysis, higher age was independently associated with lowered Δ-NWU (95% confidence interval: −0.59 to −0.16, p < 0.001). Although successful recanalization (TICI ≥ 2b) significantly reduced Δ-NWU progression by 6.4% (p < 0.001), younger age was still independently associated with higher Δ-NWU (p < 0.001). Younger age is significantly associated with increased brain edema formation after thrombectomy for LVO stroke. Younger patients might be particularly receptive targets for future adjuvant neuroprotective drugs that influence ischemic edema formation. 相似文献
48.
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50.
Kirsten K. B. Peetoom Monique A. S. Lexis Manuela Joore Carmen D. Dirksen 《Disability and rehabilitation. Assistive technology》2015,10(4):271-294
Purpose: To obtain insight into what kind of monitoring technologies exist to monitor activity in-home, what the characteristics and aims of applying these technologies are, what kind of research has been conducted on their effects and what kind of outcomes are reported. Methods: A systematic document search was conducted within the scientific databases Pubmed, Embase, Cochrane, PsycINFO and Cinahl, complemented by Google Scholar. Documents were included in this review if they reported on monitoring technologies that detect activities of daily living (ADL) or significant events, e.g. falls, of elderly people in-home, with the aim of prolonging independent living. Results: Five main types of monitoring technologies were identified: PIR motion sensors, body-worn sensors, pressure sensors, video monitoring and sound recognition. In addition, multicomponent technologies and smart home technologies were identified. Research into the use of monitoring technologies is widespread, but in its infancy, consisting mainly of small-scale studies and including few longitudinal studies. Conclusions: Monitoring technology is a promising field, with applications to the long-term care of elderly persons. However, monitoring technologies have to be brought to the next level, with longitudinal studies that evaluate their (cost-) effectiveness to demonstrate the potential to prolong independent living of elderly persons. 相似文献
- Implications for Rehabilitation
Insight was obtained of what kind of technologies exist to monitor activity of daily living, what their functionalities and outcomes of using these technologies are to prolong independent living of non-institutionalised elderly people.
Five main groups of monitoring technologies exist with a wide range of functionalities. Research into the use of monitoring technologies is widespread but in its infancy, consisting mainly of small-scale studies and including few longitudinal studies.
Research into the use of monitoring technologies demonstrated that the systems are able to monitor daily activities and have the potential of prolonging independent living of elderly people.