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21.
Tutar E Ertem D Unluguzel G Tanrikulu S Haklar G Celikel C Ademoglu E Pehlivanoglu E 《World journal of gastroenterology : WJG》2008,14(20):3218-3223
AIM: To determine the role of inflammatory cytokines and reactive oxygen species (ROS) in childhood reflux esophagitis. METHODS: A total of 59 subjects who had complaints suggesting GERD underwent esophagogastroduoden oscopy. Endoscopic and histopathologic diagnosis of reflux esophagitis was established by Savary-Miller and Vandenplas grading systems, respectively. Esophageal biopsy specimens were taken from the esophagus 20% proximal above the esophagogastric junction for conventional histopathological examination and the measurements of ROS and cytokine levels. ROS were measured by chemiluminescence, whereas IL-8 and MCP-1 levels were determined with quantitative immunometric ELISA on esophageal tissue. Esophageal tissue ROS, IL-8 and MCP-1 levels were compared among groups with and without endoscopic/histo- pathologic esophagitis. RESULTS: Of 59 patients 28 (47.5%) had normal esophagus whereas 31 (52.5%) had endoscopic esophagitis. In histopathological evaluation, almost 73% of the cases had mild and 6.8% had moderate degree of esophagitis. When ROS and chemokine levels were compared among groups with and without endoscopic esophagitis, statistical difference could not be found between patients with and without esophagitis. Although the levels of ROS, IL-8 and MCP-1 were found to be higher in the group with histopathological reflux esophagitis, this difference was not statistically significant. CONCLUSION: These results suggest that the grade of esophagitis is usually mild or moderate during childhood and factors apart from ROS, IL-8 and MCP-1 may be involved in the pathogenesis of reflux esophagitis in children. 相似文献
22.
Myocardial ischemia-reperfusion in rats: reduction of infarct size by either supplemental physiological or pharmacological doses of melatonin 总被引:1,自引:0,他引:1
Myocardial ischemia-reperfusion (I/R) represents a clinically relevant problem associated with thrombolysis, angioplasty and coronary bypass surgery. I/R injury is believed to be a consequence of free radical generation in the heart especially during the period of reperfusion. The pineal secretory product, melatonin, is known to be a potent free radical scavenger and pharmacological concentrations have been shown to reduce the I/R-induced cardiac damage in isolated rat hearts. However, the physiological role of melatonin in the prevention of this damage is unknown. Rats were pinealectomized or sham-operated (control) 2 months before the I/R studies. To produce cardiac damage, the left main coronary artery was occluded for 30 min, followed by 120 min reperfusion, in anesthetized rats. Infarct size, expressed as the percentage of the risk zone, was found significantly higher in pinealectomized rats (49+/-3.4%) than in the control group (34+/-3.6%). Melatonin administration (4 mg/kg, either before ischemia or reperfusion) to pinealectomized rats significantly reduced the infarct size values and returned them to the control values. On the other hand, melatonin administration (4 mg/kg) to sham-operated rats failed to attenuate significantly the I/R-induced infarct size. These results suggest that physiological melatonin concentrations are important in reducing the I/R-induced myocyte damage, while pharmacological concentrations of melatonin did not add to the beneficial effect. As melatonin levels have been reported to decrease with age, melatonin replacement therapy may attenuate I/R-induced myocardial injury, especially in older patients. 相似文献
23.
Mustafa Ozbaran Tahir Yagdi Cagatay Engin Zulal Ulger Burcu Ozbaran Sezen Kose Duygu Kacamak Yaprak Engin 《Pediatric transplantation》2015,19(1):82-86
As there is still a shortage of pediatric donor hearts, several techniques have been used to assist pediatric patients to survive until transplantation. VADs provide long‐term support and ability of mobilization for children before a suitable heart becomes available. Several devices such as paracorporeal pumps have been used for this purpose, with acceptable morbidity and mortality rates. However, discharge is not possible, as there is no mobile drive unit for these small‐sized pumps. The possible negative psychosocial impact of long‐term hospitalization, away from home and school, may cause some adjustment problems in the future. In this case series, three pediatric patients that underwent intracorporeal LVAD implantation and returned to school are presented to share clinical experience and also to attract attention to the potential social and psychiatric implications. 相似文献
24.
Incorporation of resident macrophages in engineered tissues: Multiple cell type response to microenvironment controlled macrophage‐laden gelatine hydrogels 下载免费PDF全文
Camille Dollinger Sait Ciftci Helena Knopf‐Marques Rabia Guner Amir M. Ghaemmaghami Christian Debry Julien Barthes Nihal Engin Vrana 《Journal of tissue engineering and regenerative medicine》2018,12(2):330-340
The success of tissue engineering strategy is strongly related to the inflammatory response, mainly through the activity of macrophages that are key cells in initial immune response to implants. For engineered tissues, the presence of resident macrophages can be beneficial for maintenance of homeostasis and healing. Thus, incorporation of macrophages in engineered tissues can facilitate the integration upon implantation. In this study, an in‐vitro model of interaction was developed between encapsulated naive monocytes, macrophages induced with M1/M2 stimulation and incoming cells for immune assisted tissue engineering applications. To mimic the wound healing cascade, naive THP‐1 monocytes, endothelial cells and fibroblasts were seeded on the gels as incoming cells. The interaction was first monitored in the absence of the gels. To mimic resident macrophages, THP‐1 cells were encapsulated in the presence or absence of IL‐4 to control their phenotype and then these hydrogels were seeded with incoming cells. Without encapsulation, activated macrophages induce apoptosis in endothelial cells. Once encapsulated no adverse effects were seen. Macrophage‐laden hydrogels attracted more endothelial cells and fibroblasts compared to monocytes‐laden hydrogels. The induction (M2 stimulation) of encapsulated macrophages did not change the overall number of attracted cells; but significantly affected their morphology. M1 stimulation by a defined media resulted in more secretion of both pro‐ and anti‐inflammatory cytokines compared to M2 stimulation. It was demonstrated that there is a distinct effect of encapsulated macrophages on the behaviour of the incoming cells; this effect can be harnessed to establish a microenvironment more prone to regeneration upon implantation. 相似文献
25.
We examined the association between serum trace elements and clinical findings such as number of sensitive tender points, severity of fatigue and functional status in patients with fibromyalgia (FM). Thirty-two patients diagnosed as having FM according to the ACR 1990 criteria and 32 normal healthy controls (NHC) were included in this study. The demographic data, disease duration, number of tender points and accompanying symptoms (fatigue, sleep disorders, headache, paresthesia, irritable bowel syndrome, sicca symptoms, Raynaud's phenomena) of the patients were noted. Visual analog scale (10 cm) was implemented to estimate daily severity of pain and fatigue. Fibromyalgia impact questionnaire was used for functional assessment. Serum selenium (mug/dL) and serum zinc (mug/dL) levels were measured by atomic absorption spectrometer. Serum magnesium (mmol/L) level was measured by the original kits of Abbott Aeroset auto-analyzer. The mean age of patients in FM group and NHC were calculated as 42.9 (SD = 7.7) years and 41.3 (SD = 9.7) years, respectively. Serum levels of zinc (P = 0.001) and magnesium (P = 0.002) were significantly decreased by FM groups, whereas there was no considerable difference with selenium levels of both groups (P > 0.05). Association between serum zinc level and number of tender points (P = 0.008) and that between fatigue and magnesium level (P = 0.003) was found as meaningful. According to the results of this study, it was asserted that serum magnesium and zinc levels may play an important role in the pathophysiology of FM. 相似文献
26.
27.
Satici Begum Gocet-Tekin Emine Deniz M. Engin Satici Seydi Ahmet 《International journal of mental health and addiction》2021,19(6):1980-1988
International Journal of Mental Health and Addiction - The world is currently experiencing a pandemic of an infectious disease called COVID-19 which has drawn global intensive attention. While... 相似文献
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29.
Fatma E. Akin Cenk Sari Sevil ?zer-Sari Aylin Demirezer-Bolat Tahir Durmaz Telat Keles Osman Ersoy Engin Bozkurt 《Saudi Journal Of Gastroenterology》2016,22(2):116-121
Background/Aim:
The aim of this study was to investigate the effects of celiac disease on cardiac functions using tissue Doppler echocardiography (TDE).Patients and Methods:
The study included 30 patients with celiac disease (CD) and 30 healthy volunteers. Echocardiographic examinations were assessed by conventional echocardiography and tissue Doppler imaging. The peak systolic velocity (S''m), early diastolic myocardial peak velocity (E''m), late diastolic myocardial peak velocity (A''m), E''m/A''m ratio, myocardial precontraction time (PCT''m), myocardial contraction time (CT''m), and myocardial isovolumetric relaxation time (IVRT''m), E to E''m ratio were measured.Results:
In pulsed wave Doppler echocardiography, mitral late diastolic flow (A) velocity and E to E''m ratio were significantly higher (P = 0.02 and P = 0,017), E/A ratio was significantly lower (P = 0.008) and IVRT was significantly prolonged (P = 0.014) in patients with CD. In TDE, S''m, E''m, and E''m/A''m ratio were significantly lower, IVRT''m was longer (P = 0.009) from septal mitral annulus and S''m, E''m, E''m/A''m ratio were significantly lower, PCT''m, PCT/ET ratio, IVRT''m were longer, and MPI was higher from lateral mitral annulus in celiac group than controls.Conclusion:
Our study confirms that patients with CD have impaired diastolic function. More importantly, we also demonstrated an impairment of myocardial systolic function in patients with CD by TDE. We recommend using TDE in addition to conventional echocardiography parameters for the cardiovascular risk assessment of patients with CD. 相似文献30.
Cardiac arrhythmias during ischemia-reperfusion (I/R) are believed to be related to free radicals generated in the heart especially during the period of reperfusion. The pineal secretory product, melatonin, is known to be a potent free radical scavenger and its pharmacological concentrations have been shown to reduce the I/R-induced arrhythmias in isolated rat hearts. However, the physiological role of melatonin in the prevention of these arrhythmias is unknown. Rats were pinealectomized (Px) or sham-operated (non-Px) (control) 2 months before the I/R studies. To produce arrhythmias, left main coronary artery was occluded for 7 min, followed by 7 min reperfusion, in anesthetized rats. The incidence of mortality resulted from irreversible ventricular fibrillation (VF) was found significantly higher in the Px rats (63%) than in the control group (25%). Melatonin administration (0.4 mg/kg, either before ischemia or reperfusion) to Px rats significantly reduced the incidence of total (irreversible plus reversible) and irreversible VF and returned them to control values. On the other hand, melatonin administration (0.4 and 4 mg/kg) to non-Px rats failed to attenuate the I/R arrhythmias, significantly. These results suggest that physiological melatonin concentrations are important to reduce the I/R-induced VF and mortality, while pharmacological concentrations of melatonin did not increase its beneficial effect on these arrhythmias. As melatonin levels have been reported to decrease with age, melatonin replacement therapy may attenuate the incidence of sudden cardiac death especially in older patients. 相似文献