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Bubbly cavitating flow generation and investigation of its erosional nature for biomedical applications
This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.The paper presents a study of the generation of hydrodynamic bubbly cavitation in microchannels to investigate the destructive energy output resulting from this phenomenon and its potential use in biomedical applications. The research performed in this study includes the experimental results from bubbly cavitation experiments and the findings showing the destructive effects of bubbly cavitating flow on selected specimens and cells. The bubbles caused by hydrodynamic cavitation are highly destructive at the surfaces of the target medium on which they are carefully focused. The resulting destructive energy output could be effectively used for good means such as destroying kidney stones or killing infected cancer cells. Motivated by this potential, the cavitation damage (material removal) to cancerous cells and chalk pieces having similar material properties as calcium phosphate in human bones was investigated. Also the potential of hydrodynamic bubbly cavitation generated at the microscale for biomedical treatments was revealed using the microchannel configuration of a microorifice (with an inner diameter of 0.147 mm and a length of 1.52cm).This work was supported by Sabancı University Internal Grant for Research Program under Grant FRG-C47004
Can the development of atrial fibrillation in patients with ischemic heart failure with low ejection fraction be predicted?
OBJECTIVE: Our aim is to determine the triggering factors of paroxysmal atrial fibrillation (PAF) in ischemic heart failure (HF) patients with low ejection fraction (EF). METHODS: Sixty patients were included in this study. Echocardiography and 24-hours Holter monitoring were performed after measurement of serum NT-pro BNP concentration. The patients were classified into two groups concerning the occurrence of PAF on Holter recordings. Biochemical and echocardiographic parameters of patients with and without PAF were compared. RESULTS: PAF was detected in 28 (46%) patients. Patients with PAF demonstrated higher NT-pro BNP levels, mitral and aortic regurgitation velocities, E/A, E/E', pulmonary capillary wedge pressure, pulmonary artery systolic pressure, left atrial volume and volume indices. NT-pro BNP was established as the predictor of PAF (OR=1.23, 95% CI: 1.08-1.42; p=0.001).ROC analysis showed an NT-pro BNP value of 2188 pg/mL as cut-off value with 68% sensitivity and 84% specificity [Area under the ROC curve (AUC)=0.826, CI 95%: 0.724-0.927; p<0.001]. CONCLUSION: The triggering factors for AF are increased intracardiac pressures, left atrial dilatation and increased wall tension. As an indicator of increased wall tension, elevated levels of NT-pro BNP predict the development of PAF
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Enrichment of Hazelnut Oil with Several Polyphenols: An Alternative Approach to A New Functional Food
Hazelnut oil has been examined according to its oxidative stability and antioxidant activity. The oil sample has been treated with gallic acid, ascorbic acid, catechin, vanillic acid,p-coumaric acid and rutin. Stability of the pure and treated oils against the oxidation has been assessed via Rancimat by detecting the protection factor. The quality parameters of the oil samples were compared depending on their antioxidant activity. D-Optimal design of Response Surface Method has been applied to optimize the enrichment conditions of hazelnut oil with several polyphenols. Principal component analysis has been applied to comprehend the relationship between the groups and their quality parameters. Depending on the analysis of variance test, the most important parameter (at p < 0.0001) affecting the relevant system has been found polyphenol type with respect to stability and antioxidant capacity. Gallic acid has enhanced the stability of hazelnut oil against oxidation similar to 3 times over that of pure sample. The maximum yields of protection factor, antioxidant activity and dissolved polyphenol level have been 2.738, 46.14% and 259.424 ppm under the optimum conditions (300 ppm gallic acid)
H-1-magnetic resonance spectroscopy in obsessive-compulsive disorder: effects of 12 weeks of sertraline treatment on brain metabolites
Several neuroimaging studies have investigated brain metabolite abnormalities in patients with obsessive-compulsive disorder (OCD) and also explored metabolic changes after OCD treatments using proton magnetic resonance spectroscopy (H-1-MRS). The main objective of this study was to investigate the effects of a selective serotonin re-uptake inhibitor (SSRI) treatment on the neurochemical levels in patients with OCD. In the present study, levels of N-acetylaspartate (NAA), choline, and myo-Inositol were measured in terms of their ratios with creatine (Cr) using H-1-MRS. The ratios of metabolite levels in the three brain regions for 19 unmedicated patients with OCD, including 10 who were drug-na < ve, at baseline and following 12 weeks of sertraline treatment and for 19 healthy control subjects were compared with ANOVA. In post hoc analysis, the NAA/Cr levels were significantly lower in patients with OCD at baseline than in healthy controls in the anterior cingulate and in the caudate. On the other hand, no significant differences were detected in terms of the NAA/Cr in the anterior cingulate, caudate, and putamen between the patients with OCD after 12 weeks of sertraline treatment and healthy controls. The paired t test revealed that NAA/Cr levels were significantly higher in patients with OCD after 12 weeks of sertraline treatment compared with those at baseline in the anterior cingulate and in the caudate. Our results suggest that reductions in NAA can be reversed with SSRI treatment, which may indicate an improvement in neuronal integrity
Proton magnetic resonance spectroscopy in obsessive-compulsive disorder: Evidence for reduced neuronal integrity in the anterior cingulate
Neuroimaging studies have suggested that dysfunction of the corlico-slrialal-Lhalamo-corLical (CSTC) circuit is a key pathophysiologic feature of obsessive-compulsive disorder (OCD). Several studies using llllproton magnetic resonance spectroscopy (H-1 MRS) have found abnormal neural metabolite concentrations among OCD patients. The aim of this study was to investigate the metabolic integrity of the anterior cingulate, caudate and putamen in OCD. In the present study, 32 unmedicated patients with OCD, including 23 who were drug-naIve, were compared using MRS with 32 healthy controls. Metabolite levels of N-acetylaspartate (NAA), choline (Cho) and myo-inositol (ml) were measured in terms of their ratios to creatine (Cr). The ratio of NAA/Cr was significantly lower in OCD patients than in healthy controls in the anterior cingulate. There was a tendency for levels of NAA/Cr to be lower in the caudate and the putamen in patients with OCD compared with healthy controls. NAA/Cr ratios were negatively correlated with the total scores on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) in the anterior cingulate in patients with OCD. Our results support the significance and biochemical involvement of the anterior cingulate cortex (ACC) in the pathophysiology of OCD. (C)2014 Elsevier Ireland Ltd. All rights reserved
Optimizing the extraction of polyphenols from Sideritis montana L. using response surface methodology
Sideritis montana L. endemic of Turkey was screened for its polyphenols content and antioxidant activity. Factor analysis and experimental design have been applied to understand the structure of the separation process, to determine the effective parameters, and to accomplish the performance improvement. Face-centred composite design (FCD) of response surface methodology (RSM) was applied to evaluate the influences of solvent concentration, solvent amount, extraction time, and stirring speed of homogenizer-assisted extraction (HAE) as well as to model and to optimize the HAE. Quadratic models were highly significant (p < 0.0001) for the responses studied with high coefficients of determination (R-2) of 0.9440, 0.9415 and 0.9521. The result of the study suggests that 15.02 mL of 22.69% EtOH solution (v/v), 70.16 s, and 9524.52 rpm of mixing speed are the optimal conditions to obtain the highest yield of total polyphenols (TPC) and flavonoids (TFC), and the best antioxidant activity (AA). Rosmarinic acid was identified as the most abundant component. (C) 2018 Elsevier B.V. All rights reserved
Current Status of the Use of Single-Nucleotide Polymorphisms in Forensic Practices
Forensic geneticists often use short tandem repeats (STRs) to solve cases. However, STRs can be insufficient when DNA samples are degraded due to environmental exposure and mass disasters, alleged and real relatives are genetically related in paternity or kinship analyses, or a suspect is lacking. In such cases, single-nucleotide polymorphisms (SNPs) can provide valuable information and thus should be seriously considered as a tool to help resolve challenging cases. In this review, the current status of SNP analyses in forensic applications and the comparative advantages and disadvantages of SNPs with other biomarkers are discussed
Current Status of the Use of Single-Nucleotide Polymorphisms in Forensic Practices
Forensic geneticists often use short tandem repeats (STRs) to solve cases. However, STRs can be insufficient when DNA samples are degraded due to environmental exposure and mass disasters, alleged and real relatives are genetically related in paternity or kinship analyses, or a suspect is lacking. In such cases, single-nucleotide polymorphisms (SNPs) can provide valuable information and thus should be seriously considered as a tool to help resolve challenging cases. In this review, the current status of SNP analyses in forensic applications and the comparative advantages and disadvantages of SNPs with other biomarkers are discussed