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71.
72.
Kara MA Smits ME Rosmolen WD Bultje AC Ten Kate FJ Fockens P Tytgat GN Bergman JJ 《Gastrointestinal endoscopy》2005,61(6):671-678
BACKGROUND: Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barrett's esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study. METHODS: Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist. RESULTS: Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens. CONCLUSIONS: In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE. 相似文献
73.
Effects of octreotide and propranolol on colonic mucosa in rats with portal hypertensive colopathy 总被引:2,自引:0,他引:2
BACKGROUND/AIMS: The aim of the study is to clarify the effects of octreotide and propranolol, agents used in the treatment of portal hypertension, on mucosal changes in portal hypertensive colopathy. METHODOLOGY: Portal hypertension was induced in all rats by partial portal vein ligation, and after the operation all rats were caged for a 10-week period. Then, animals were divided into three groups and for two weeks medical treatment were administered to the individual groups as follows: Control group, saline 0.5 mL/day, intraperitoneally. Octreotide group, octreotide 100 micrograms/kg/12 hours, subcutaneously. Propranolol group, propranolol 20 mg/kg/day, intraperitoneally. In order to assess the portal hypertensive colopathy, criteria such as mean diameters of dilated vessels in colonic mucosa, and the existence of mucosal edema, capillary ectasia, hyperemia and hemorrhage, inflammation were used. RESULTS: When parameters were compared for the control versus propranolol groups, mucosal edema and hyperemia and hemorrhage criteria were found to be significant for the propranolol group; control versus octreotide groups, mucosal edema, capillary ectasia, and hyperemia and hemorrhage criteria were found to be significant for the octreotide group; octreotide versus propranolol groups, capillary ectasia and mucosal edema criteria were found to be significant for the octreotide group. CONCLUSIONS: The mucosal changes in portal hypertensive colopathy could be corrected by drugs modifying portal blood flow, octreotide may find a place in the treatment of portal hypertensive colopathy. 相似文献
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75.
Apoor S Gami Dave O Hodge Regina M Herges Eric J Olson Jiri Nykodym Tomas Kara Virend K Somers 《Journal of the American College of Cardiology》2007,49(5):565-571
OBJECTIVES: This study sought to identify whether obesity and obstructive sleep apnea (OSA) independently predict incident atrial fibrillation/flutter (AF). BACKGROUND: Obesity is a risk factor for AF, and OSA is highly prevalent in obesity. Obstructive sleep apnea is associated with AF, but it is unknown whether OSA predicts new-onset AF independently of obesity. METHODS: We conducted a retrospective cohort study of 3,542 Olmsted County adults without past or current AF who were referred for an initial diagnostic polysomnogram from 1987 to 2003. New-onset AF was assessed and confirmed by electrocardiography during a mean follow-up of 4.7 years. RESULTS: Incident AF occurred in 133 subjects (cumulative probability 14%, 95% confidence interval [CI] 9% to 19%). Univariate predictors of AF were age, male gender, hypertension, coronary artery disease, heart failure, smoking, body mass index, OSA (hazard ratio 2.18, 95% CI 1.34 to 3.54) and multiple measures of OSA severity. In subjects <65 years old, independent predictors of incident AF were age, male gender, coronary artery disease, body mass index (per 1 kg/m2, hazard ratio 1.07, 95% CI 1.05 to 1.10), and the decrease in nocturnal oxygen saturation (per 0.5 U log change, hazard ratio 3.29, 95% CI 1.35 to 8.04). Heart failure, but neither obesity nor OSA, predicted incident AF in subjects > or =65 years of age. CONCLUSIONS: Obesity and the magnitude of nocturnal oxygen desaturation, which is an important pathophysiological consequence of OSA, are independent risk factors for incident AF in individuals <65 years of age. 相似文献
76.
N. Kara S. Narayanan R. H. Belmaker H. Einat V. A. Vaidya G. Agam 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(7)
Background:
The term adult neurogenesis constitutes a series of developmental steps including the birth, survival, differentiation, maturation, and even death of newborn progenitor cells within neurogenic niches. Within the hippocampus progenitors reside in the neurogenic niche of the subgranular zone in the dentate gyrus subfield. At the different stages, designated type-I, type-IIa, type-IIb, type-III, and granule cell neurons, the cells express a series of markers enabling their identification and visualization. Lithium has been shown to increase hippocampal cell proliferation in the subgranular zone of the hippocampal dentate gyrus subfield of adult rodents and to stimulate the proliferation of hippocampal progenitor cells in vitro, but data regarding lithium’s ability to increase neuronal differentiation and survival is equivocal.Methods:
To clarify the effect of lithium on adult hippocampal neurogenesis, we identified the effect of chronic lithium treatment on distinct stages of hippocampal progenitor development using adult Nestin-green fluorescent protein transgenic mice and immunofluorescent techniques.Results:
The present observations confirm that lithium targets the initial stages of progenitor development enhancing the turnover of quiescent neural progenitors/putative stem-cells, corroborating previous reports. However, the enhanced quiescent neural progenitor-turnover does not translate into an increased number of immature neurons. We also observed a steep decline in the number of type-III immature neurons with complex tertiary-dendrites, suggesting that lithium alters the morphological maturation of newborn neurons.Conclusions:
Our results do not corroborate previous reports of lithium-induced enhanced numbers of newly generated neurons. 相似文献77.
Cuprizone‐induced demyelination and demyelination‐associated inflammation result in different proton magnetic resonance metabolite spectra 下载免费PDF全文
Jelle Praet Jasmien Orije Firat Kara Caroline Guglielmetti Eva Santermans Jasmijn Daans Niel Hens Marleen Verhoye Zwi Berneman Peter Ponsaerts Annemie Van der Linden 《NMR in biomedicine》2015,28(4):505-513
Conventional MRI is frequently used during the diagnosis of multiple sclerosis but provides only little additional pathological information. Proton MRS (1H‐MRS), however, provides biochemical information on the lesion pathology by visualization of a spectrum of metabolites. In this study we aimed to better understand the changes in metabolite concentrations following demyelination of the white matter. Therefore, we used the cuprizone model, a well‐established mouse model to mimic type III human multiple sclerosis demyelinating lesions. First, we identified CX3CL1/CX3CR1 signaling as a major regulator of microglial activity in the cuprizone mouse model. Compared with control groups (heterozygous CX3CR1+/? C57BL/6 mice and wild type CX3CR1+/+ C57BL/6 mice), microgliosis, astrogliosis, oligodendrocyte cell death and demyelination were shown to be highly reduced or absent in CX3CR1?/? C57BL/6 mice. Second, we show that 1H‐MRS metabolite spectra are different when comparing cuprizone‐treated CX3CR1?/? mice showing mild demyelination with cuprizone‐treated CX3CR1+/+ mice showing severe demyelination and demyelination‐associated inflammation. Following cuprizone treatment, CX3CR1+/+ mice show a decrease in the Glu, tCho and tNAA concentrations as well as an increased Tau concentration. In contrast, following cuprizone treatment CX3CR1?/? mice only showed a decrease in tCho and tNAA concentrations. Therefore, 1H‐MRS might possibly allow us to discriminate demyelination from demyelination‐associated inflammation via changes in Tau and Glu concentration. In addition, the observed decrease in tCho concentration in cuprizone‐induced demyelinating lesions should be further explored as a possible diagnostic tool for the early identification of human MS type III lesions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
78.
79.
Kadir Serafettin Tekgunduz Mustafa Kara Ibrahim Caner Yasar Demirelli 《Iranian journal of pediatrics.》2015,25(4)
Background:
Although it is well described among adults, intravenous colistin use and its associated toxicities in newborns are poorly understood.Objectives:
We present our experience of efficacy and safety of intravenous colistin in the treatment of sepsis in term and preterm neonates.Patients and Methods:
The records of neonates who received colistin between January 2013 and February 2014 were retrospectively reviewed. All neonates with culture proven nosocomial infections due to multidrug resistant organisms and treated continuously with colistin for more than 72 hours were included in the study.Results:
Patients were evaluated for clinical and microbiological response to the drug and its and side effects. Twelve newborn infants with mean 31.8 ± 3.5 weeks gestational age and median 1482 (810 - 3200) gram birth weight were included. 11/12 (91.7%) patients showed microbiological clearance with intravenous colistin. One patient who had recurrent cerebrospinal fluid positive culture was treated with intraventricular colistin. The major side effects observed was hyponatremia and hypokalemia in 2 (16.6%) patients, all infants required magnesium supplementation.Conclusions:
Intravenous colistin administration appears to be safe and efficacious for multidrug-resistant gram-negative infections in neonates, including preterm infants. However, we believe that large prospective controlled studies are needed to confirm its efficacy and safety in neonates. 相似文献80.
Areeba Kara Deborah DeMeester Lindsey Lazo Emily Cook Susan Hendricks 《Journal of interprofessional care》2018,32(4):513-516
Interprofessional collaboration is fundamental to providing optimal patient care. The readiness of the team entering a framework of interprofessional collaborative practice is critical to its success. In this study, we conducted an interprofessional education (IPE) activity for medical and nursing students in an acute care setting. Over nine occasions, 21 student pairs (one nursing and one medical student per pair) jointly assessed a patient and created a list of problems and interventions to achieve the patient’s goals. Immediately after the activity, students were debriefed to gain insight into their experiences. Debriefing sessions were audiotaped and analysed using a phenomenological approach and four major themes were identified. Overall, students felt responsible for representing their profession and were initially apprehensive about the interprofessional task. Nevertheless, they identified their own shortcomings and recognized the value in their partner’s approach. These realizations promoted convergence on a shared vision to provide optimal care for patients as a team. Acknowledging and understanding these perceptions may help design better ways to improve patient care. This educational model may be utilized by others who are seeking IPE activities in acute care. 相似文献