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81.
Jussi Nikkola Irina Rinta-Kiikka Sari Räty Johanna Laukkarinen Riitta Lappalainen-Lehto Satu Järvinen Hanna Seppänen Isto Nordback Juhani Sand 《Journal of gastrointestinal surgery》2014,18(1):164-171
Objective
The long-term morphological changes induced by a single episode of alcoholic pancreatitis are not known. Our aim was to study these morphological changes in secretin-stimulated magnetic resonance cholangiopancreatography (S-MRCP) after the first episode of alcohol-associated acute pancreatitis and to evaluate the risk factors and possible protective factors potentially associated with later chronic findings. We have previously reported 2-year follow-up results in pancreatic morphology. This study extends the follow-up to 9 years.Patients and Methods
In this prospective follow-up study, S-MRCP imaging was performed for 44 (41 M, 3 F; mean age, 46 (25–68)?years) patients after their first episode of alcohol-associated pancreatitis. Pancreatic morphology was evaluated at 3 months and at 2, 7, and 9 years after hospitalization. Recurrent attacks of pancreatitis were studied and pancreatic function was monitored by laboratory tests. Patients’ alcohol consumption was evaluated with questionnaires, laboratory markers, and self-estimated alcohol consumption via interview. Smoking and body mass index were annually recorded.Results
At 3 months, 32 % of the patients had normal findings in S-MRCP, 52 % had acute, and 16 % had chronic changes. At 7 years, S-MRCP was performed on 36 patients with normal findings in 53 %, the rest (47 %) having chronic findings. Pancreatic cyst was present in 36 %, parenchymal changes in 28 %, and atrophy in 28 % of the cases. There were no new changes in the pancreas in the attending patients between 7 and 9 years (18 patients). Of the patients with only acute findings at 3 months, 60 % resolved to normal in 7 years, but the rest (40 %) showed chronic changes later on. The initial attack was mild in 65 %, moderate in 25 %, and severe in 10 % of the patients. Patients with mild first attack had fewer chronic changes at 7 years compared to patients with moderate or moderate and severe together (p?=?0.03, p?=?0.01). Of the patients in the seventh year of S-MRCP, 22 % had suffered a recurrent episode of acute pancreatitis (mean, 22 (2–60)?months) and 11 % had a clinical diagnosis of chronic pancreatitis. At 7 years, 88 % of the patients with recurrences had chronic findings in S-MRCP versus 36 % with nonrecurrent pancreatitis (p?=?0.02). Six (17 %) patients abstained from alcohol throughout follow-up (mean, 8.7 (7–9.1)?years), but even one of these developed pancreatic atrophy. Out of the non-abstinent patients who did not suffer recurrences, 4/22 (18 %) had developed new findings during at follow-up S-MRCP (NS). In univariate analysis, heavy smoking showed no correlation with increased chronic changes compared to nonsmoking.Conclusions
Morphological pancreatic changes increase with recurrent episodes of acute pancreatitis. Patients with mild first attack have fewer chronic changes in the pancreas in the long term. However, even a single episode of acute alcoholic pancreatitis may induce chronic morphological changes in long-term follow-up. 相似文献82.
Hüseyin Ayhan Tahir Durmaz Telat Keleş Cenk Sari Abdullah Nabi Aslan Haci Ahmet Kasapkara 《Scandinavian cardiovascular journal : SCJ》2014,48(3):184-188
Background and aim. It has been demonstrated that right ventricular systolic dysfunction develops soon after surgical aortic valve replacement (s-AVR). While the impact of s-AVR or TAVI on the function of the left ventricle has been studied with various imaging modalities, little is known about the impact on right ventricular function (RVF). In the current study, we evaluated the impact of TAVI on RVF using conventional echocardiography parameters. Methods and results. Echocardiography was performed prior to 24 h, 1 month and 6 months after TAVI. RVF was assessed using (1) tricuspid annular plane systolic excursion (TAPSE); (2) RV Tissue Doppler Imaging (S’); (3) right ventricular systolic pressure (RVSP); (4) Fractional area change (FAC); and (5) RV ejection fraction (RVEF). TAVI was performed through the subclavian artery in two patients and femoral artery in 48 patients with an Edwards Sapien XT valve. TAVI was performed on 50 patients between the dates of December 2012 and June 2013. After TAVI, a statistically significant improvement was observed for all parameters related to RVF (RVSP, RVEF, TAPSE, FAC, RVTDI S’). During the 1st and 6th months this statistically significant improvement continued in TAPSE and FAC, and there was no deterioration in RVSP, RVEF, and RVTDI S during the 1st month but a statistically significant improvement continued in the 6th month. Conclusion. RVF assessed by conventional echocardiography did not deteriorate after TAVI in early and midterm follow-up. Further, TAVI provides improvement of RVF and can safely and efficiently be performed in patients with impaired RVF. 相似文献
83.
Kaisa Nieminen Juha Immanen Marjukka Laxell Leila Kauppinen Petr Tarkowski Karel Dolezal Sari Thtiharju Annakaisa Elo Mlanie Decourteix Karin Ljung Rishikesh Bhalerao Kaija Keinonen Victor A. Albert Yk Helariutta 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(50):20032-20037
Although a substantial proportion of plant biomass originates from the activity of vascular cambium, the molecular basis of radial plant growth is still largely unknown. To address whether cytokinins are required for cambial activity, we studied cytokinin signaling across the cambial zones of 2 tree species, poplar (Populus trichocarpa) and birch (Betula pendula). We observed an expression peak for genes encoding cytokinin receptors in the dividing cambial cells. We reduced cytokinin levels endogenously by engineering transgenic poplar trees (P. tremula × tremuloides) to express a cytokinin catabolic gene, Arabidopsis CYTOKININ OXIDASE 2, under the promoter of a birch CYTOKININ RECEPTOR 1 gene. Transgenic trees showed reduced concentration of a biologically active cytokinin, correlating with impaired cytokinin responsiveness. In these trees, both apical and radial growth was compromised. However, radial growth was more affected, as illustrated by a thinner stem diameter than in WT at same height. To dissect radial from apical growth inhibition, we performed a reciprocal grafting experiment. WT scion outgrew the diameter of transgenic stock, implicating cytokinin activity as a direct determinant of radial growth. The reduced radial growth correlated with a reduced number of cambial cell layers. Moreover, expression of a cytokinin primary response gene was dramatically reduced in the thin-stemmed transgenic trees. Thus, a reduced level of cytokinin signaling is the primary basis for the impaired cambial growth observed. Together, our results show that cytokinins are major hormonal regulators required for cambial development. 相似文献
84.
Vittorio Fortino Lukas Wisgrill Paulina Werner Sari Suomela Nina Linder Erja Jalonen Alina Suomalainen Veer Marwah Mia Kero Maria Pesonen Johan Lundin Antti Lauerma Kristiina Aalto-Korte Dario Greco Harri Alenius Nanna Fyhrquist 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(52):33474
85.
Matti Aarnio Sari Lindblom-Ylänne Juha Nieminen Eeva Pyörälä 《Advances in health sciences education : theory and practice》2014,19(3):329-345
Recent research on problem-based learning (PBL) has shown that students need support when dealing with conflicting ideas in PBL-tutorial discussions. In the present study, we examined tutor facilitation during tutorial discussions, and particularly how the facilitation helped students to collaboratively resolve conflicts on knowledge. The study involved four PBL-tutorial sessions that included altogether 33 first-year medical and dental students. The sessions were videotaped and analysed using qualitative interaction analysis. Our aim was to find out how the tutor interventions encouraged students to elaborate on conflicting ideas, and how the interventions differed between conflict and non-conflict situations. We also examined how the tutors intervened during conflicts about factual or conceptual knowledge. The tutorial discussions included 92 tutor intervention episodes and 43 conflict episodes. The tutors intervened during 24 of the conflict episodes and resolved 13 of these episodes. Generally, the tutors often intervened by confirming what the students had said or by giving explanations, but they rarely asked questions that would stimulate the elaboration of knowledge. During conflicts on knowledge the tutors gave more explanations, but did little to encourage the students to deal with conflicting ideas. The tutors more often resolved conflicts on factual knowledge than conceptual knowledge. The findings suggest that tutor training should focus on promoting tutors’ understanding on when to give direct explanations, and when and how to encourage students to collaboratively elaborate on conflicting ideas. 相似文献
86.
87.
Taner Akar Mustafa Karapirli Ramazan Akcan Birol Demirel Barış Akduman Ahmet Zahit Dursun Serhat Sari Alper Özkök 《Archives of gerontology and geriatrics》2014
According to World Health Organization, the life expectancy at birth is increasing. An increase in life expectancy might result in increased morbidity and mortality in elderly. The increase in the elderly population also leads to an increase in medico-legal problems, as well. Autopsy is of high importance for determination of cause of death in clinical and forensic cases. The purpose of this study was to find out general characteristics elderly deaths by examining forensic autopsy records. 相似文献
88.
Tahir Durmaz Huseyin Ayhan Telat Keles Abdullah Nabi Aslan Kemal Esref Erdogan Cenk Sari Emine Bilen Murat Akcay Engin Bozkurt 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2014,41(4):414-417
Transcatheter aortic valve replacement can be an effective, reliable treatment for severe aortic stenosis in surgically high-risk or ineligible patients. However, various sequelae like coronary artery obstruction can occur, not only in the long term, but also immediately after the procedure. We present the case of a 78-year-old woman whose left main coronary artery became obstructed with calculus 2 hours after the transfemoral implantation of an Edwards Sapien XT aortic valve. Despite percutaneous coronary intervention in that artery, the patient died. This case reminds us that early recognition of acute coronary obstruction and prompt intervention are crucial in patients with aortic stenosis who have undergone transcatheter aortic valve replacement. 相似文献
89.
90.
Seyhan Sahan‐Firat Meryem Temiz‐Resitoglu Demet Sinem Guden Sefika Pinar Senol Ayse Nihal Sari Meltem Cil Demet Unsal Belma Korkmaz Bahar Tunctan Kafait U. Malik Cuneyt Kemal Buharalioglu 《Clinical and experimental pharmacology & physiology》2019,46(2):173-182
We have previously demonstrated that the activation of the spleen tyrosine kinase (Syk)/inhibitory‐κB (IκB)‐α/nuclear factor‐κB (NF‐κB) p65 signalling pathway contributes to hypotension and inflammatory response in a rat models of zymosan (ZYM)‐induced non‐septic shock. The purpose of this study was to further examine the possible mechanism underlying the effect of inhibition of Syk by BAY61‐3606 via NF‐κB activity at the level of nuclear translocation regarding the production of vasodilator and proinflammatory mediators in lipopolysaccharide (LPS) (septic)‐ and ZYM (non‐septic)‐induced shock. Administration of LPS (10 mg/kg, ip) or ZYM (500 mg/kg, ip) to male Wistar rats decreased mean arterial pressure and increased heart rate that was associated with an increase in the activities of cyclooxygenase and nitric oxide synthase, tumour necrosis factor‐α, and interleukin‐8 levels, and NF‐κB activation and nuclear translocation in sera and/or cardiovascular and renal tissues. BAY61‐3606 (3 mg/kg, ip), the selective Syk inhibitor, given 1 hour after LPS‐ or ZYM injection reversed all the above‐mentioned effects. These results suggest that Syk contributes to the LPS‐ or ZYM‐induced hypotension and inflammation associated with transactivation of NF‐κB in septic and non‐septic shock. 相似文献