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91.
Pancreatic cells contain specialised stores for ATP. Purinergic receptors (P2 and P1) and ecto-nucleotidases are expressed in both endocrine and exocrine calls, as well as in stromal cells. The pancreas, especially the endocrine cells, were an early target for the actions of ATP. After the historical perspective of purinergic signalling in the pancreas, the focus of this review will be the physiological functions of purinergic signalling in the regulation of both endocrine and exocrine pancreas. Next, we will consider possible interaction between purinergic signalling and other regulatory systems and their relation to nutrient homeostasis and cell survival. The pancreas is an organ exhibiting several serious diseases - cystic fibrosis, pancreatitis, pancreatic cancer and diabetes - and some are associated with changes in life-style and are increasing in incidence. There is upcoming evidence for the role of purinergic signalling in the pathophysiology of the pancreas, and the new challenge is to understand how it is integrated with other pathological processes. 相似文献
92.
Nguyen CT Jung W Kim J Chaney EJ Novak M Stewart CN Boppart SA 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(24):9529-9534
Otitis media (OM), a middle-ear infection, is the most common childhood illness treated by pediatricians. If inadequately treated, OM can result in long-term chronic problems persisting into adulthood. Children with chronic OM or recurrent OM often have conductive hearing loss and communication difficulties and require surgical treatment. Tympanostomy tube insertion, the placement of a small drainage tube in the tympanic membrane (TM), is the most common surgical procedure performed in children under general anesthesia. Recent clinical studies have shown evidence of a direct correspondence between chronic OM and the presence of a bacterial biofilm within the middle ear. Biofilms are typically very thin and cannot be recognized using a regular otoscope. Here we report the use of optical coherent ranging techniques to noninvasively assess the middle ear to detect and quantify biofilm microstructure. This study involves adults with chronic OM, which is generally accepted as a biofilm-related disease. Based on more than 18,537 optical ranging scans and 742 images from 13 clinically infected patients and 7 normal controls using clinical findings as the gold standard, all middle ears with chronic OM showed evidence of biofilms, and all normal ears did not. Information on the presence of a biofilm, along with its structure and response to antibiotic treatment, will not only provide a better fundamental understanding of biofilm formation, growth, and eradication in the middle ear, but also may provide much-needed quantifiable data to enable early detection and quantitative longitudinal treatment monitoring of middle-ear biofilms responsible for chronic OM. 相似文献
93.
Novak K Polic S Capkun V Fabijanic D Lukin A Dujic Z Rumboldt Z 《Archives of gerontology and geriatrics》2012,54(1):266-270
Previous studies have shown a paradoxical increase in early mortality in older patients (>70 years) with acute STEMI treated with fibrinolytic therapy (FT), which has been attributed to the development of free wall rupture (FWR). Our aim was to assess occurrence of FWR in STEMI patients receiving FT. In this 7-year prospective study, data from 1701 consecutive patients were obtained. We analyzed predictors of the in-hospital mortality in patients > 70 years old. The independent contribution of several variables to overall mortality and FWR development was assessed using multiple logistic regression analyses. The mortality of entire cohort was 18% (306/1701). Diabetes mellitus, anterior infarction, smoking, female gender and hypercholesterolemia were independent predictors of in-hospital mortality. FT was given to 18% of all patients (304/1701) of which 13% died (39/304). FWR was 18.4-times more often in patients who received FT. Among patients younger than 70 years who received FT there was no FWR, while in patients ≥70 years of age FWR was found in almost half of the deceased (30/68; 44%). Application of FT in STEMI patients is not associated with higher mortality, but significantly increases number of FWR, especially in patients over 70 years of age. 相似文献
94.
A reduction in calorie intake [caloric restriction (CR)] appears to consistently decrease the biological rate of aging in a variety of organisms as well as protect against age-associated diseases including chronic inflammatory disorders such as cardiovascular disease and diabetes. Although the mechanisms behind this observation are not fully understood, identification of the main metabolic pathways affected by CR has generated interest in finding molecular targets that could be modulated by CR mimetics. This review describes the general concepts of CR and CR mimetics as well as discusses evidence related to their effects on inflammation and chronic inflammatory disorders. Additionally, emerging evidence related to the effects of CR on periodontal disease in non-human primates is presented. While the implementation of this type of dietary intervention appears to be challenging in our modern society where obesity is a major public health problem, CR mimetics could offer a promising alternative to control and perhaps prevent several chronic inflammatory disorders including periodontal disease. 相似文献
95.
96.
Sweden was the first country to introduce online Chlamydia trachomatis testing for both men and women and this article provides information about the user characteristics and which risk groups are reached with this method. During the years 2005-2007 a questionnaire was administered with a response rate of 86% (n = 6025) (62.5% women, 37.5% men). Over 60% of respondents were aged below 26 years and single. The average years of education for men and women was 14 (range 9.0-26.0). The mean Internet usage time was 22.4 hours/week among men and 15.5 hours/week among women. Only 22% men and 34% women had tested themselves for C. trachomatis at clinics previously. Respondents reported a higher frequency of previous sexually transmitted infections (STIs) compared with other Internet users (i.e. C. trachomatis: men 19%, women 24%). Eighty percent of online test users had engaged in sex with ≥ 2 partners without a condom during the previous year. Online C. trachomatis test users are mostly young people with high sexual risk behaviour. 相似文献
97.
98.
Andrea Nagy Laszlo Bognar Istvan Pataki Zoltan Barta Laszlo Novak 《Child's nervous system》2013,29(3):413-418
Purpose
The aim of the study was to compare the characteristics of ventriculosubgaleal shunts during the clinical course of posthemorrhagic and postinfectious hydrocephalus in the neonatal period.Patients and methods
The study comprised 102 premature babies in whom subgaleal shunt was consecutively inserted between 2006 and 2011. Seventy-two patients had posthemorrhagic hydrocephalus (mean gestational age 27.3?±?2.1 weeks, mean birth weight 1,036.9?±?327.7 g, mean age at insertion 51.4?±?56.2 days) and 30 patients were operated postinfectiously (27.5?±?2.2 weeks, 1,064.7 g?±?310.7 g, 115.9?±?47.8 days).Results
The mean survival of subgaleal shunts was 87.9 days for the posthemorrhagic group and 75.6 days for the postinfectious group. Only six infants (8.3 %) did not need ventriculoperitoneal shunts later, all posthemorrhagic. There were meaningful differences between two groups with regard to ventriculosubgaleal shunt-related infections (8.3 % in posthemorrhagic versus 20.0 % in postinfectious) and shunt revision rate (6.9 % in posthemorrhagic versus 13.3 % in postinfectious), but these were not statistically significant. The need of ventriculoscopic procedures was notably more frequent in postinfectious group (1.4 versus 23.3 %).Conclusion
In premature infants with ventriculomegaly, the subgaleal shunt is an effective temporary diversion tool. The complications were less with posthemorrhagic than with postinfectious hydrocephalus. With previous severe infections of prematures, the risk for complications regarding infection and obstruction will be 2.75 and 2.06 (odds ratios) times higher and more frequent need of ventriculoscopic procedures should be considered (odds ratio 21.6). 相似文献99.
Visnja Padjen Marie Bodenant Dejana R. Jovanovic Nelly Ponchelle-Dequatre Novak Novakovic Charlotte Cordonnier Ljiljana Beslac-Bumbasirevic Didier Leys 《Journal of neurology》2013,260(12):3049-3054
The question of whether i.v. rt-PA is beneficial in patients with ischaemic stroke and atrial fibrillation (AF) remains unresolved. Our objective was to evaluate the outcome of patients with AF who received i.v. rt-PA for stroke in the registries of Lille (France) and Belgrade (Serbia). End-points were poor outcome [modified Rankin Scale (mRS) 3–6], and symptomatic haemorrhagic transformation (sHT) according to ECASS3. Of 734 consecutive patients, 155 (21.2 %) had AF. The unadjusted comparison found patients with AF to be 12 years older, more likely to be women, to have hypertension, and baseline INR > 1.2, and less likely to be smokers. They had higher baseline NIHSS scores, diastolic blood pressure, and serum glucose concentrations, and lower platelet counts. They did not differ for sHT (5.8 vs. 5.5 %; p = 0.893), but they more frequently had poor outcomes (52.3 vs. 35.2 %; p < 0.001) and death (21.9 vs. 9.0 %; p < 0.001). The only independent predictor of sHT was baseline NIHSS (adjOR 1.05 per 1 point increase; 95 % CI 1.01–1.10). Independent variables associated with poor outcome were age (adjOR 1.04 for 1 year increase; 95 % CI 1.03–1.06), baseline NIHSS (adjOR 1.17 per 1 point increase; 95 % CI 1.13–1.21), and sHT (adjOR 47.6; 95 % CI 10.2–250) but not AF. In patients treated with i.v. rt-PA for cerebral ischaemia, those with AF have worse outcomes because they are older and have more severe strokes at admission. This result suggests that we should focus on prevention and research of more aggressive strategies at the acute stage. 相似文献
100.
Cathy Lu Brandon Baraty Helen Lee Robertson Alexis Filyk Hua Shen Tak Fung Kerri Novak Christopher Ma Remo Panaccione Jean-Paul Achkar Sara El Ouali David Bruining Vipul Jairath Brian Feagan Florian Rieder the Stenosis Therapy Research Consortium 《Alimentary pharmacology & therapeutics》2020,51(12):1233-1246