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101.
Glutathione in blood cells decreases without DNA breaks after a simulated saturation dive to 250 msw
INTRODUCTION: Saturation diving involves exposure to high pressure and elevated oxygen level. The impact of cellular defense systems like glutathione in protecting cells against oxidative DNA damage seems unclear. The aim of the present study was, therefore, to investigate whether diving conditions would affect blood cell glutathione and thus alter the mononuclear cells' (MNC) susceptibility to oxidative DNA damage. METHODS: Eight subjects participated in a simulated saturation dive to 2.6 MPa (250 msw) lasting 19.3 d (0.8 d compression, 6.6 d bottom phase, 11.9 d decompression) breathing helium-oxygen with PO2 ranging from 35 to 70 kPa (3.5-7.0 msw). Blood samples collected before compression and after decompression were analyzed for glutathione content and single-stranded DNA breaks. RESULTS: The results demonstrate for the first time that a simulated saturation dive decreased glutathione content in peripheral blood cells (32% decrease in MNC), and that the decrease was most pronounced in the erythrocytes (45%). Remarkably, no single-stranded DNA breaks could be detected in the MNC despite the low glutathione level. DISCUSSION: The results suggest that glutathione is a useful indicator of oxidative stress and that a low glutathione level represents no significant harm to the blood cells in the absence of other toxic agents. The lack of DNA strand breaks suggests that protection against oxidative DNA damage was mainly provided by mechanisms other than the glutathione system. Although previous investigations point to hyperoxia as the most plausible explanation for the present observations, the effect of high pressure cannot be excluded. 相似文献
102.
Søren S Olesen Louise Kuhlmann Srdan Novovic Camilla Nøjgaard Evangelos Kalaitzakis Nanna M Jensen Trond Engjom Georg Dimcevski Anne Waage Stephan L Haas Miroslav Vujasinovic Romualdas Riauka Aldis Pukitis Imanta Ozola-Zālīte Alexey Okhlobystin Mikael Parhiala Johanna Laukkarinen Asbjørn M Drewes for the Scandinavian Baltic Pancreatic Club 《Journal of gastroenterology and hepatology》2020,35(2):326-333
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Søren Schou Olesen Abdulkarim Harakow Klaus Krogh Asbjørn Mohr Drewes Aase Handberg Peter Astrup Christensen 《Pancreatology》2021,21(2):334-341
BackgroundSevere hypertriglyceridemia (HTG) is a well-known risk factor for acute pancreatitis, but updated population-based estimates on incidence of HTG-associated pancreatitis are lacking.MethodsWe identified all individuals with severe HTG (triglyceride level >10 mmol/L [886 mg/dL]) in a population-based sample from 2008 to 2019 and linked these with Danish nationwide health-registers to identify patients with acute pancreatitis. Pancreatitis cases were subsequently confirmed by a detailed medical chart review. Crude and standardized incidence rates were estimated and studied in relation to age, gender and time-period. In addition, aetiological classification designated during index hospitalization, severity and follow-up of individuals with HTG-associated pancreatitis were studied.ResultsAmong 2146 individuals with severe HTG during the observation period, 75 were diagnosed with acute pancreatitis (3.5%). The mean incidence rate of HTG-associated pancreatitis was 1.4 (95% CI, 1.1–1.7) per 100,000 person years for the total population, for women it was 0.7 (95% CI, 0.5–1.1) and for men 2.0 (95% CI, 1.5–2.6) per 100,000 person-years. The mean incidence rate increased from 0.7 to 1.7 per 100,000 person-years from 2008 to 2019 (ptrend = 0.01). The highest incidence rate of HTG-associated pancreatitis was observed for men in the age group 50–59 years. An elevated triglyceride level was recognized as aetiological risk factor in 35% of patients during index hospitalization.ConclusionsOnly a fraction of patients with severe HTG are hospitalized for acute pancreatitis, but the incidence is increasing. In more than half of patients elevated triglycerides is not recognized as a risk factor for acute pancreatitis during index hospitalization. 相似文献
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Bj?rn?BlombergEmail author Davis?SM?Mwakagile Willy?K?Urassa Samwel?Y?Maselle Marcellina?Mashurano Asbj?rn?Digranes Stig?Harthug Nina?Langeland 《BMC public health》2004,4(1):45
Background
Antimicrobial resistance is particularly harmful to infectious disease management in low-income countries since expensive second-line drugs are not readily available. The objective of this study was to implement and evaluate a computerized system for surveillance of antimicrobial resistance at a tertiary hospital in Tanzania. 相似文献109.
Arøen A Løken S Heir S Alvik E Ekeland A Granlund OG Engebretsen L 《The American journal of sports medicine》2004,32(1):211-215
BACKGROUND: Traumatic articular cartilage injuries heal poorly and may lead to development of osteoarthritis at a young age. This study estimates the number of patients who may benefit from one of the surgical methods of cartilage repair. METHODS: All patients undergoing knee arthroscopy during a 6-month period at three collaborating hospitals were consecutively evaluated according to the International Cartilage Repair Society (ICRS) knee form. The material consists of 993 consecutive knee arthroscopies in patients with median age of 35 years. RESULTS: Preoperative radiographs demonstrated degenerative changes in 13% of the knees. Articular cartilage pathology was found in 66% and a localized cartilage defect was found in 20% of the knees. A localized full-thickness cartilage lesion (ICRS grade 3 and 4) was observed in 11% of the knees. Of the localized full-thickness lesions, 55% (6% of all knees) had a size above 2 cm(2). CONCLUSION: Eleven percent of all knee arthroscopies show cartilage defects that may be suitable for cartilage repair procedures. However, the natural history of these lesions and the number of patients that will benefit from a cartilage repair procedure are so far unknown. 相似文献
110.
The relation between sale of antimicrobial drugs and antibiotic resistance in uropathogens in general practice 总被引:4,自引:0,他引:4
BACKGROUND: Overuse of antimicrobial drugs has resulted in an alarming increase in bacterial resistance in most countries. The relevance for general practice is unknown. OBJECTIVE: To evaluate the impact of the sale of antimicrobial drugs on bacterial resistance as found in uropathogens from general practice. SETTING: General practice in Belgium and Norway. METHODS: Observational study. RESULTS: The sale of antimicrobial drugs indicated for use in the treatment of urinary tract infection was four times higher in Belgium than in Norway (18.5 vs 4.4 DDD/1000 inhabitants/day). The antibiotic resistance reported by microbiological laboratories as valid for general practice was significant higher in Belgium than in Norway (ampicillins (44% vs 27%), co-trimoxazole (28% vs 17%), fluoroquinolones (12% vs 2%) and nitrofurantoin (16% vs 11%, p < 0.0001 for all). However, the antibiotic resistance found in urine samples from dysuric women in general practice was similar (trimethoprim 14% vs 12%, co-trimoxazole 14% vs 11%, nitrofurantoin 7% vs 3%), except in the case of ampicillins (30% vs 19%, p < 0.05). CONCLUSION: The impact of the antimicrobial sale on resistance in uropathogens seems less than expected at the general practice level, even though local microbiological reports mention fairly high antibiotic resistance data. Adapted methods for following-up bacterial resistance evolution in general practice are needed. 相似文献