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101.
Swift F Franzini-Armstrong C Øyehaug L Enger UH Andersson KB Christensen G Sejersted OM Louch WE 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(10):3997-4001
Cardiomyocyte contraction and relaxation are controlled by Ca(2+) handling, which can be regulated to meet demand. Indeed, major reduction in sarcoplasmic reticulum (SR) function in mice with Serca2 knockout (KO) is compensated by enhanced plasmalemmal Ca(2+) fluxes. Here we investigate whether altered Ca(2+) fluxes are facilitated by reorganization of cardiomyocyte ultrastructure. Hearts were fixed for electron microscopy and enzymatically dissociated for confocal microscopy and electrophysiology. SR relative surface area and volume densities were reduced by 63% and 76%, indicating marked loss and collapse of the free SR in KO. Although overall cardiomyocyte dimensions were unaltered, total surface area was increased. This resulted from increased T-tubule density, as revealed by confocal images. Fourier analysis indicated a maintained organization of transverse T-tubules but an increased presence of longitudinal T-tubules. This demonstrates a remarkable plasticity of the tubular system in the adult myocardium. Immunocytochemical data showed that the newly grown longitudinal T-tubules contained Na(+)/Ca(2+)-exchanger proximal to ryanodine receptors in the SR but did not contain Ca(2+)-channels. Ca(2+) measurements demonstrated a switch from SR-driven to Ca(2+) influx-driven Ca(2+) transients in KO. Still, SR Ca(2+) release constituted 20% of the Ca(2+) transient in KO. Mathematical modeling suggested that Ca(2+) influx via Na(+)/Ca(2+)-exchange in longitudinal T-tubules triggers release from apposing ryanodine receptors in KO, partially compensating for reduced SERCA by allowing for local Ca(2+) release near the myofilaments. T-tubule proliferation occurs without loss of the original ordered transverse orientation and thus constitutes the basis for compensation of the declining SR function without structural disarrangement. 相似文献
102.
Østensen M Förger F Nelson JL Schuhmacher A Hebisch G Villiger PM 《Annals of the rheumatic diseases》2005,64(6):839-844
OBJECTIVE: To investigate changes in the levels of circulating cytokines with a focus on the Th1/Th2 balance during and after pregnancy in patients with rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA), and ankylosing spondylitis (AS). METHODS: Plasma and serum samples of 34 pregnant patients, 19 with RA, 6 with JIA, and 9 with AS, and of 30 healthy pregnant women, 20 non-pregnant patients, and 10 non-pregnant healthy women were analysed for levels of interferon gamma (IFNgamma), interleukin (IL) 1beta, IL10, IL1 receptor antagonist (IL1Ra), soluble tumour necrosis factor receptor (sTNFR), and soluble CD30 (sCD30) by ELISA. Clinical assessment and blood sampling in pregnant women was done once in each trimester and 6, 12, and 24 weeks post partum. Disease activity in the patients was evaluated by validated clinical instruments and correlated with circulating levels of cytokines. RESULTS: Low levels of IL10 were found sporadically, whereas IFNgamma and IL1beta were below detection level in the samples tested. Significantly higher concentrations of sTNFR and IL1Ra were measured in pregnant than in non-pregnant subjects. An increase of IL1Ra from the second to the third trimester correlated with improvement of disease activity in patients with RA and AS. Compared with non-pregnant patients and the other pregnant women, patients with RA showed markedly raised levels of sCD30 during pregnancy. CONCLUSIONS: IFNgamma and IL10, markers of a Th1 and Th2 response, respectively, were either low or undetectable in the cohorts analysed. The increase of cytokine inhibitors IL1Ra and sTNFR was related to pregnancy and was independent of an underlying disease. These anti-inflammatory mediators seem to affect disease activity. 相似文献
103.
104.
A. GUSTAFSSON S. LUND-TØNNESEN A. BERSTAD T. MIDTVEDT E. NORIN 《Scandinavian journal of gastroenterology》2013,48(7):721-727
Background: Antibiotic-associated diarrhoea (AAD) may range from mild disturbances to severe pseudomembranous colitis. Many antibiotics affect several intestinal microflora-associated characteristics, such as short-chain fatty acid (SCFA) pattern. In the present study we investigated SCFAs in 31 patients on admittance to the hospital for severe AAD. Nine patients were followed up more extensively after they had received an enema containing faecal microflora from a healthy person on a Western diet. Methods: Faecal SCFAs were determined by gas chromatography. The enema was characterized before use. Results: AAD patients showed significant disturbances in faecal SCFA pattern. Clinically, most enema-treated patients recovered within days and had no relapses within 18 months. Conclusions: Intestinal microflora showed great disturbances, and the amounts of SCFAs were reduced, although the diarrhoea was not related to total amount SCFAs. Administration of a faecal enema resulted in the clinical recovery of most patients with severe diarrhoea within 4 days. 相似文献
105.
Summary Major changes occur in the serum level of several hormones during 5 days of heavy and continuous physical activities, with less than a total of 2 h of sleep. The present investigation was designed to evaluate the importance of caloric deficiency, energy requirement being about 8,000–10,000 kcal/24 h. A comparison between well fed subjects and those with food deprivation revealed significantly higher levels of (T3) triiodothyronin, insulin and thyroid stimulating hormone (TSH) in the well-fed subjects, who also had lower levels of growth hormone (hGH) and cortisol, whereas no difference was found between the two groups for thyroxin (T4). Increased levels were found for T3 and T4 in both groups during the first day of activity, with a concomitant decrease in TSH and a subsequent decrease of T4 during the next 2 days. T3 decreased only in the low-calory group whereas increased levels were found in the iso-calory group throughout the course. The resting levels of insulin decreased during the course in the low-calory group whereas it increased in the iso-calory group. High levels were maintained throughout the course for hGH. Cortisol showed high levels just before the start of the course and then decreased from day 2 to day 4. No difference was found between the morning and evening levels for cortisol, indicating disappearance of the circadian rhythm. The present investigation has shown that energy deficiency during prolonged physical strain is responsible for the decreased serum levels of T3 and insulin and may contribute to the decrease in TSH and the increase in hGH and cortisol. 相似文献
106.
Nordentoft M Thorup A Petersen L Ohlenschlaeger J Melau M Christensen TØ Krarup G Jørgensen P Jeppesen P 《Schizophrenia Research》2006,83(1):29-40
BACKGROUND: Only a few randomized clinical trials have tested the effect on transition rates of intervention programs for patients with sub-threshold psychosis-like symptoms. AIM: To examine whether integrated treatment reduced transition to psychosis for first-contact patients diagnosed with schizotypal disorder. METHODS: Seventy-nine patients were randomized to integrated treatment or standard treatment. Survival analysis with multivariate Cox-regression was used to identify factors determinant for transition to psychotic disorder. RESULTS: In the multivariate model, male gender increased risk for transition to psychotic disorder (relative risk=4.47, (confidence interval 1.30-15.33)), while integrated treatment reduced the risk (relative risk=0.36 (confidence interval 0.16-0.85)). At two-year follow-up, the proportion diagnosed with a psychotic disorder was 25.0% for patients randomized to integrated treatment compared to 48.3% for patients randomized to standard treatment. CONCLUSION: Integrated treatment postponed or inhibited onset of psychosis in significantly more cases than standard treatment. 相似文献
107.
Identification of critical receptors in seizure controlling brain regions may facilitate the development of more efficacious pharmacological therapies against nerve agent intoxication. In the present study, a number of drugs with anticonvulsant potency were microinfused into the perirhinal cortex (PRC) or posterior piriform cortex (PPC) in rats. The drugs used exert cholinergic antagonism (scopolamine), glutamatergic antagonism (ketamine, NBQX), both cholinergic and glutamatergic antagonism (procyclidine, caramiphen), or GABAergic agonism (muscimol). The results showed that in the PRC anticonvulsant efficacy against soman-induced seizures (subcutaneously administered) was achieved by procyclidine or NBQX, but not by ketamine, scopolamine, caramiphen, or muscimol (Experiment 1). Hence, both muscarinic and glutamatergic NMDA receptors had to be antagonized simultaneously or AMPA receptors alone, suggesting increased glutamatergic activation in the PRC before onset of seizures. In the PPC, anticonvulsant effects were assured by scopolamine or muscimol, but not by procyclidine, caramiphen, NBQX, or ketamine (Experiment 2). Thus, muscarinic and GABAA receptors appear to be the critical ones in the PPC. Microinfusion of soman into the PRC or PPC resulted in sustained seizure activity in the majority of the rats of both infusion categories. The rhinal structures encompassed in this study apparently have critical functions as both control and trigger sites for nerve agent-evoked seizures. 相似文献
108.
A national study on conditional survival,excess mortality and second cancer after high dose therapy with autologous stem cell transplantation for non‐Hodgkin lymphoma 下载免费PDF全文
Knut B. Smeland Cecilie E. Kiserud Grete F. Lauritzsen Anne K. Blystad Unn‐Merete Fagerli Ragnhild S. Falk Øystein Fluge Alexander Fosså Arne Kolstad Jon H. Loge Martin Maisenhölder Bjørn Østenstad Stein Kvaløy Harald Holte 《British journal of haematology》2016,173(3):432-443
This national population‐based study aimed to investigate conditional survival and standardized mortality ratios (SMR) after high‐dose therapy with autologous stem‐cell transplantation (HDT‐ASCT) for non‐Hodgkin lymphoma (NHL), and to analyse cause of death, relapses and second malignancies. All patients ≥18 years treated with HDT‐ASCT for NHL in Norway between 1987 and 2008 were included (n = 578). Information from the Cause of Death Registry and Cancer Registry of Norway were linked with clinical data. The 5‐, 10‐ and 20‐year overall survival was 61% (95% confidence interval [CI] 56–64%), 52% (95%CI 48–56%) and 45% (95%CI 40–50%), respectively. The 5‐year survival conditional on having survived 2, 5 and 10 years after HDT‐ASCT was 81%, 86% and 93%. SMRs were 12·3 (95%CI 11·0–13·9), 4·9 (95%CI 4·1–5·9), 2·4 (95%CI 1·8–3·2) and 1·0 (95%CI 0·6–1·8) for the entire cohort and for patients having survived 2, 5 and 10 years after HDT‐ASCT respectively. Of the 281 deaths observed, 77% were relapse‐related. Treatment‐related mortality was 3·6%. The 10‐year cumulative incidence of second malignancies was 7·9% and standardized incidence ratio was 2·0 (95%CI 1·5–2·6). NHL patients treated with HDT‐ASCT were at increased risk of second cancer and premature death. The mortality was still elevated at 5 years, but after 10 years mortality equalled that of the general population. 相似文献
109.
Claus Lohman Brasen Lone Frischknecht Dorthe Ørnskov Lotte Andreasen Jonna Skov Madsen 《Scandinavian journal of clinical and laboratory investigation》2017,77(1):60-65
Background: Lactase persistence is an autosomal dominant trait commonly distributed in Europe as well as some parts of east Africa and the Arabian Peninsula. Using real-time PCR to detect the ?13910C?>?T variant common in the European population is a reliable analysis although other variants in the probe-binding site may cause errors in analysis. The aim of this study was to determine the prevalence of the variants in a Danish cohort examined for lactose intolerance as well as to improve the real-time PCR analysis for detection of the different variants.Methods: We genotyped 3395 routine samples using real-time PCR for the ?13910C?>?T-variant. All consecutive samples identified as ?13910CC were sequenced using Sanger Sequencing. Using the SDS software we examined various quality value settings to improve on the genetic analysis.Results: Using real-time PCR resulted in 100% successful genotyping of the ?13910C?>?T variant. By using a quality value of 99% and sequencing the undetermined samples we improved the ability of the assay to identify variants other than ?13910C?>?T. This resulted in a reduction of the diagnostic error rate by a factor of 2.4 while increasing the expenses only 3%.Conclusions: We conclude that using a quality value of 99% in the SDS software significantly improves the diagnostic efficiency of the real-time PCR assay for detecting variants associated to lactase persistence. 相似文献
110.