Electrodiagnostic methods to verify Guillain-Barré syndrome subtypes in Istanbul: A prospective multicenter study.

BACKGROUND AND AIMS: This study aimed to identify the clinical characteristics and electrodiagnostic subtypes of Guillain-Barré syndrome (GBS) in Istanbul. METHODS: Patients with GBS were prospectively recruited between April 2019 and March 2022 and two electrodiagnostic examinations were performed on each patient. The criteria of Ho et al., Hadden et al., Rajabally et al., and Uncini et al. were compared for the differentiation of demyelinating and axonal subtypes, and their relations with anti-ganglioside antibodies were analyzed. RESULTS: One hundred seventy-seven patients were included, 69 before the coronavirus disease 2019 pandemic (April 2019-February 2020) and 108 during the pandemic (March 2020-March 2022), without substantial changes in monthly frequencies. As compared with the criteria of Uncini et al., demyelinating GBS subtype diagnosis was more frequent according to the Ho et al. and Hadden et al. criteria (95/162, 58.6% vs. 110/174, 63.2% and 121/174, 69.5%, respectively), and less frequent according to Rajabally et al.'s criteria (76/174, 43.7%). Fourteen patients' diagnoses made using Rajabally et al.'s criteria were shifted to the other subtype with the second electrodiagnostic examination. Of the 106 analyzed patients, 22 had immunoglobulin G anti-ganglioside antibodies (14 with the axonal subtype). They had less frequent sensory symptoms (54.5% vs. 83.1%, p = 0.009), a more frequent history of previous gastroenteritis (54.5% vs. 22.9%, p = 0.007), and a more severe disease as compared with those without antibodies. INTERPRETATION: Serial electrodiagnostic examinations are more helpful for accurate subtype diagnosis of GBS because of the dynamic pathophysiology of the disease. We observed no significant increase in GBS frequency during the pandemic in this metropolis.

Global longitudinal strain score predicts all cause death in patients with chronic total occlusion with preserved ejection fraction.

OBJECTIVE: Change in LVEF is one of the most important indicators of prognosis in CTO cases. Studies in patients with CTO have shown improvement in LVEF approximately at 3 and 6 months after successful PCI. It has been shown that LV global longitudinal strain (GLS) starts to improve even 1 day after CTO-PCI. We aimed at investigating the effect of subclinical echocardiographic involvement on all-cause mortality in the group with CTO and preserved ejection fraction by evaluating the LV GLS score. PATIENTS AND METHODS: Patients with LVEF ≥ 50% were considered to have preserved ejection fraction and were included in the study. The endpoint of the study was all-cause death. For this retrospective study, 1,171 patients with coronary angiography who had had CTO in any of their vessels were screened. RESULTS: A total of 86 consecutive patients were reviewed in the study. The optimum GLS score cut-off value (≥ 14.18) for predicting mortality was determined using receiver operating characteristic (ROC) curve analysis (AUC: 0.897, sensitivity 87.5%, specificity 81.5% p<0.001). At a mean follow-up of 49 months, a significant difference was found between the two groups in all-cause mortality determined by the GLS score [2 (3.4%) vs. 14 (51.9%), p<0.001]. A significant difference in mortality was observed between the group with a low GLS score and the group with a high GLS score, according to Kaplan-Meier analysis. The effect of GLS score in predicting all-cause mortality was demonstrated in multivariate cox regression analysis (Low GLS score; OR: 6.36 95%CI (1.039-39.013), p=0.045). Cox regression multivariate analysis and the effect of GLS score in predicting mortality were observed [Low GLS score; OR: 6.368 95%CI (1.039-39.013), p=0.045]. CONCLUSIONS: As a predictor, GLS may be a valuable marker of cardiac subclinical dysfunction for all caused mortality in CTO patients.

Development of a solventless method for the pesticides analysis.

This paper represents the results of a case study investigating the development of a novel, simple, cost-effective, solventless and sensitive chromatographic method for the determination of volatile pesticides in aqueous samples by an electrothermally prepared pencil graphite (PG). In this study, PG were conditioned by passing a suitable direct current to activate PG by Joule effect. Conditioned PG was used for the extraction of Chlorpyrifos (CP), which is used as case study. The method was also found successful in the determination of CP in real water samples, providing acceptable recovery values (82-111%).

Contribution of brainstem circuits in pathophysiology of NREM-sleep parasomnias.

OBJECTIVE: We aimed to investigate the brainstem circuits to reveal if there was any abnormality in these circuits in clinically diagnosed patients with NREM parasomnias during wakefulness. METHODS: Twelve patients with NREM-sleep parasomnia diagnosed according to ICSD-3 criteria and a control group of 16 healthy subjects were enrolled into our study. We analyzed the auditory startle reflex (ASR), blink reflex (BR), prepulse inhibition (PPI) of BR and recovery excitability of BR. RESULTS: There was a trend for longer responses from orbicularis oculi and sternocleidomastoid muscles after auditory stimulation in the patients compared to those in the healthy subjects. The recovery percentages at 200 ms and 300 ms showed a borderline significance in the patients. No significant difference was found in the R2-PPI between the patients and healthy subjects. CONCLUSIONS: Our results suggest a mildly enhanced ASR and relatively early facilitation of BR excitability in patients with NREM-sleep parasomnia during daytime. Although our findings suggest involvement of brainstem networks in NREM-sleep parasomnia during wakefulness, it would be better to study these networks at night and during daytime to see if there is any contribution.

The role of pedunculopontine nucleus in isolated REM sleep behavior disorder and REM sleep without atonia.

INTRODUCTION: The aim of this study was to analyze the functions of pedunculopontine nucleus (PPN) in isolated REM sleep behavior disorder (iRBD) and REM sleep without atonia (RSWA) to investigate the role of PPN in dream-enacting motor behaviors in RBD. We evaluated the activity of PPN through the prepulse modulation (PPM) together with other brainstem reflexes to investigate the differences in changes at brainstem. METHODS: We included nine patients with isolated RSWA and 10 patients with iRBD. For diagnosis, all patients underwent polysomnography. None of the patients had parkinsonism or dementia. We also included 17 healthy participants with similar age and sex. Blink reflex (BR), PPM of BR, recovery excitability of BR, and auditory startle reflex (ASR) were recorded in all participants. RESULTS: There was a prepulse inhibition deficit in iRBD and RSWA groups compared to healthy subjects. The BR-R2 recovery at 200 ms interval was also higher in patients with iRBD and RSWA. In ASR recordings, the response probabilities were higher in the RBD group compared to RSWA and control groups. CONCLUSION: The PPM was abnormal in both iRBD and RSWA whereas ASR was enhanced in iRBD. We suggest that there are certain similarities and differences in the pathophysiologies of iRBD and RSWA.

An effective electrochemical biosensing platform for the detection of reduced glutathione.

A biosensor was developed using glutathione peroxidase (GSH-Px) as the enzyme. Firstly, platinum (Pt) nanoparticles were deposited onto a glassy carbon paste electrode (GCPE), and then GSH-Px was immobilized by means of gelatin that was then crosslinked with glutaraldehyde. The measurement was based on the electrochemical oxidation of GSH to its disulfide form in the presence of hydrogen peroxide. The linear range was found to be between 10 and 250 µM, with a correlation coefficient of R(2) = 0.9968. The R.S.D value for 25 µM GSH (n = 6) was calculated as 2.92%. Finally, the proposed biosensor was used to analyze GSH in a synthetically prepared plasma sample, and a promising recovery value was obtained.

A novel polythiophene - ionic liquid modified clay composite solid phase microextraction fiber: Preparation, characterization and application to pesticide analysis.

This report comprises the novel usage of polythiophene - ionic liquid modified clay surfaces for solid phase microextraction (SPME) fiber production to improve the analysis of pesticides in fruit juice samples. Montmorillonite (Mmt) clay intercalated with ionic liquids (IL) was co-deposited with polythiophene (PTh) polymer coated electrochemically on an SPME fiber. The surface of the fibers were characterized by using scanning electron microscopy (SEM). Operational parameters effecting the extraction efficiency namely; the sample volume and pH, adsorption temperature and time, desorption temperature and time, stirring rate and salt amount were optimized. In order to reveal the major effects, these eight factors were selected and Plackett-Burman Design was constructed. The significant parameters detected; adsorption and temperature along with the stirring rate, were further investigated by Box-Behnken design. Under optimized conditions, calibration graphs were plotted and detection limits were calculated in the range of 0.002-0.667ng mL(-1). Relative standard deviations were no higher than 18%. Overall results have indicated that this novel PTh-IL-Mmt SPME surface developed by the aid of electrochemical deposition could offer a selective and sensitive head space analysis for the selected pesticide residues.

Ionic liquid intercalated clay sorbents for micro solid phase extraction of steroid hormones from water samples with analysis by liquid chromatography-tandem mass spectrometry.

Clay material plays an important role in the transport and retention of many compounds in the soil, therefore, clay based sorbents are promising alternatives for selective sorption of organic pollutants. In the present work, different chain length ionic liquids (ILs) namely, 1-methyl-3-octyl-imidazolium bromide, 1-methyl-3-undecyl-imidazolium bromide and 1-methyl-3-octadecyl-imidazolium bromide were intercalated in the galleries of montmorillonite (MMT) clay. Then, this novel nanofiller surface was utilized in micro extraction of estrogenic hormones for the first time. A fast procedure where sonication-assisted emulsification microextraction combined with vortex assisted micro-solid phase extraction (µ-SPE) was developed for the LC-MS/MS analysis of estrone (E1), 17ß-estradiol (E2), estriol (E3) and ethynylestradiol (EE2). The parameters related to the µ-SPE procedure namely; pH, sorbent amount, extraction solvent type and volume, sonication and vortex time, sample volume and salt effect on the extraction efficiency were screened by applying Plackett-Burmann design. The selected parameters were then optimized by using Box-Behnken design. The method was validated for the determination of estrogenic hormone residues in river water samples. Linear calibration plots were obtained for all hormones whose regression coefficients were larger than 0.98. RSD values were found less than 10% for three levels of concentration. LOD levels were calculated as; 0.012, 0.062, 0.018 and 0.693 ng L(-1) for E1, E2, E3 and EE2, respectively. Recovery values were calculated in the range of 86.9-97.7%. Considering large sample volumes required for attaining low limits of these hormones, present method provides an ease for analyst as 10 mL of the sample is adequate for achieving the same sensitivity.

The predictors of poor outcomes in patients with femoral artery injuries.

PURPOSE: This study investigated the predictors of poor outcomes, including limb loss and death, in patients with femoral artery injuries. PATIENTS AND METHODS: The study included 158 patients aged 2-82 (mean age 28.4 ± 16.5) with femoral arterial injury (common, deep, and superficial femoral artery) that were treated surgically between 2000 and 2010. Isolated venous injuries were excluded. Demographic and clinical data of the patients, including age, gender, admission time, pulse rate and blood pressure, hematocrit value, reason of injury, associated injury, and Mangled Extremity Severity Score (MESS) were recorded. RESULTS: Of the 158 patients, the death and amputation rates were 5.7% (9) and 5.1% (8), respectively. In logistic regression analysis, four variables (pulse rate, MESS, hematocrit, and bone trauma) were found to be independent predictors for poor outcomes. The Odd's ratios and confidence interval values of these variables were as follows: 7.24 (1.94-26.92), 21.75 (5.41-87.48), 5.93 (3.04-11.54) and 7.46 (2.09-9.56), respectively. CONCLUSIONS: The MESS value, presence of bone fracture, hematocrit, and pulse rate on admission are predictive risk factors for poor outcomes in patients with femoral artery injury. Therefore, in these patients, prompt intervention by experienced surgeons is crucial for limb salvage and decreased mortality.

Preparation and characterization of sodium dodecyl sulfate doped polypyrrole solid phase micro extraction fiber and its application to endocrine disruptor pesticide analysis.

A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its surface to exert better selectivity and hence the developed polymerized surface could offer to analyst to exploit it as a fiber in headspace SPME analysis. The parameters, mainly, adsorption temperature and time, desorption temperature, stirring rate and salt amount were optimized to be as 70°C and 45min, 200°C, 600rpm and 10gL(-1), respectively. Limit of detection was estimated in the range of 0.073-1.659ngmL(-1) for the pesticides studied. The developed method was applied in to red wine sample with acceptable recovery values (92-107%) which were obtained for these selected pesticides.

Non-valvular atrial fibrillation in the elderly; preliminary results from the National AFTER (Atrial Fibrillation in Turkey: Epidemiologic Registry) Study.

OBJECTIVE: This study aimed at the assessment of the clinical approach to atrial fibrillation (AF) in the older population and the consistency with the guidelines based on the records of the multicenter, prospective AFTER (Atrial Fibrillation in Turkey: Epidemiologic Registry) study. PATIENTS AND METHODS: 2242 consecutive patients admitted to the Cardiology Outpatient Clinics of 17 different tertiary Health Care Centers with at least one AF attack determined on electrocardiographic examination, were included in the study. Among the patients included in the study, 631 individuals aged 75 years and older were analyzed. RESULTS: The mean age of the patients was determined as 80.3±4.2 years. The most frequent type of AF in geriatric population was the persistent-permanent type with a percentage of 88%. 60% of the patients with AF were female. Hypertension was the most common co-morbidity in patients with AF (76%). While in 16% of patients a history of stroke, transient ischemic attack or systemic thromboembolism was present, a history of bleeding was present in 14% of the patients. 37% of the patients were on warfarin treatment and 60% of the patients were on aspirin treatment. In 38% of the patients who were on oral anticoagulant treatment, INR level was in the effective range. CONCLUSIONS: The rate of anticoagulant use in the elderly with AF was 37% and considering the reason of this situation was the medication not being prescribed by the physician, one should pay more attention particularly in the field of treatment.

The association between mean platelet volume and coronary collateral circulation.

BACKGROUND: Platelets are important in the pathogenesis of atherosclerotic complications. Higher mean platelet volume (MPV) levels are related to greater in vitro aggregation, and have been identified as an independent risk factor for myocardial infarction, and for death or recurrent vascular events. AIM: To determine the relationship between MPV and the coronary collateral circulation. METHODS: The sample consisted of 96 patients with coronary artery disease, and patients were separated into two groups according to their poorly developed or well-developed collateral circulation. Coronary collateral vessels were analyzed according to the Cohen and Rentrop grading system of 0-3. RESULTS: All analyses were conducted using SPSS 11.5 (SPSS for Windows 11.5, Chicago, IL, USA). Continuous variables were expressed as mean ± SD, and categorical variables were expressed as percentages. Comparison of categorical and continuous variables between the group with well-developed coronary collateral vessels and the group with poorly developed vessels was performed using the chi-squared test and independent samples t-test, respectively. Platelet count and MPV values were similar between the two groups. CONCLUSIONS: Our study found that MPV levels are not related to coronary collateral circulation.  

Modified gold surfaces by 6-(ferrocenyl)hexanethiol/dendrimer/gold nanoparticles as a platform for the mediated biosensing applications.

An electrochemical biosensor mediated by using 6-(Ferrocenyl) hexanethiol (FcSH) was fabricated by construction of gold nanoparticles (AuNPs) on the surface of polyamidoamine dendrimer (PAMAM) modified gold electrode. Glucose oxidase (GOx) was used as a model enzyme and was immobilized onto the gold surface forming a self assembled monolayer via FcSH and cysteamine. Cyclic voltammetry and amperometry were used for the characterization of electrochemical response towards glucose substrate. Following the optimization of medium pH, enzyme loading, AuNP and FcSH amount, the linear range for the glucose was studied and found as 1.0 to 5.0mM with the detection limit (LOD) of 0.6mM according to S/N=3. Finally, the proposed Au/AuNP/(FcSH+Cyst)/PAMAM/GOx biosensor was successfully applied for the glucose analysis in beverages, and the results were compared with those obtained by HPLC.

Assessment of DFG-S19 method for the determination of common endocrine disruptor pesticides in wine samples with an estimation of the uncertainty of the analytical results.

A gas chromatographic method for the determination of endocrine disruptor pesticides (Chlorpyrifos, Penconazole, Procymidone, Iprodione, Bromopropylate and Lambda-Cyhalothrin) in wine samples is described. A general DFG-S19 method for residual pesticide determination in all kind of food stuff was investigated to simplify and adopt for wine samples in this work. Alternative sample preparation routes were elucidated and compared according to their recovery values. Four different separation techniques were tested and the method employing florosil column after a LLE procedure was applied for wine samples with satisfactory recovery ratios (72-97%). The pesticides were extracted from the sample by cyclohexane-ethyl acetate mixture (1:1 v/v) and cleaned up by florosil column. The regression coefficients were at least 0.99 and relative standard deviations were no higher than 16%. Detection limits were in the range of 0.6-2.9 ng/mL and the relative expanded measurement uncertainties were calculated in the 7-22% range.

Relation of interatrial duration and p wave terminal force as a novel indicator of severe mitral regurgitation.

OBJECTIVES: Interatrial duration is defined as prolonged p wave on electrocardiogram. p waves with a negative terminal phase recorded in V1 enclosing an area of one small square on the electrocardiogram is significantly and strongly correlated with interatrial duration. The aim of study was to investigate whether interatrial duration with p terminal force can be used as reflection of echocardiographic severity of mitral regurgitation. MATERIALS AND METHODS: Sixty two consecutive patients with mitral regurgitation. were prospectively studied. Age/gender matched 57 subjects who had normal mitral structure and did not have mitral regurgitation. Patients with mitral regurgitation referred to a single cardiac center for echocardiography and who met the entry criteria documented moderate or severe mitral regurgitation with sinus were included. The interatrial duration was defined on the routine 12-lead electrocardiogram (50 mm/s, 10 mm/mV) using the greatest duration of p waves from D2, D3, AVF and V1. RESULTS: There was a positive correlation between interatrial duration (>/= 110 ms) and effective regurgitant orifice (r = 0.3, p < 0.001). However, left atrial diameter and brain natriuretic peptide were significantly higher in cases with mitral regurgitation. There was also strong correlation between interatrial duration (>/= 110 ms) and p terminal force and left atrial diameter. ROC analysis revealed that interatrial duration of > 110 msec. could predict of severe mitral regurgitation with 88% sensitivity and 100% specificity. CONCLUSIONS: Severe mitral regurgitation, left atrial diameter was correlated with p terminal force and interatrial duration. Significant interatrial duration (>/= 110 ms) and p terminal force might be considered as novel indicators of severe mitral regurgitation.

Head space voltammetry: a novel voltammetric method for volatile organics and a case study for phenol.

Present paper describes the results of a novel method which combines the Head space (HS) preconcentration of the analyte on the electrode prior to the voltammetric analysis. Thereafter, the method was called HS-Voltammetry. The performance of the method was tested upon using an electroactive and volatile molecule, phenol molecule, which gives an oxidation peak at conventional electrodes. In this study, a glassy carbon electrode was modified with polypyrrole by electropolymerization and then, the electrode was placed over the solution in a sealed vial heated gently on a hotplate with a stirrer for phenol determination. By controlling the thickness of the polymeric coating and optimizing preconcentration parameters such as vial pH and temperature, stirring rate and exposure time, a very consistent (5.2% at 5.0×10(-7) M) fraction of the analyte can be extracted during a predetermined time. The oxidation peak current at 0.8 V depended linearly on the phenol concentration over a wide range (3 orders of magnitude). The detection limit was estimated as 7.0×10(-8) M at 60 °C (S/N=3) which is well below the limit set by the European Community for phenols in wastewaters (ca. 5×10(-6) M). The effect of other phenolic compounds was also examined and it was shown that head space preconcentration eliminated the interference of non-volatile phenolic acids studied. For volatile phenolic compounds, the selectivity can be maintained in cases when isolated peaks are obtained for each component. The proposed method has been applied successfully for the determination of phenol in artificial wastewater and recovery percentage was calculated as 93%.

Development of a gas chromatographic method for the determination of Chlorpyrifos and its metabolite Chlorpyrifos-oxon in wine matrix.

A reliable method has been developed for the determination of Chlorpyrifos (CP) and its metabolite Chlorpyrifos-oxon (CPO) in wine sample using pulsed splitless technique coupled with gas chromatography by using electron capture detector. In this study, a quick, easy and cheap sample preparation method (QuEChERS) based on liquid extraction with acetonitrile, followed by dispersive solid phase extraction using primary secondary amine was tested for the separation and quantification of CP and CPO in wine samples. The accuracy of the developed method was tested upon recovery studies and it was calculated as (92.3 ± 18.2)% for CP and (96.6 ± 16.1)% for CPO. LOD and LOQ values of CP were found as 0.04 and 0.15 ng/mL and 0.49 and 1.62 ng/mL for CPO respectively. By using the pulsed splitless injection mode, the sensitivity of the determination of CP and its metabolite CPO in wine samples was improved compared to splitless technique. CP content of analyzed wine sample was found as 2.05 ± 0.15 ng/mL with a RSD of 7.6% and CPO content was found as 4.99 ± 0.15 ng/mL with a RSD of 3.0% (n=3). The expanded measurement uncertainties were calculated as 17% and 6% for CP and CPO, respectively.

Correlation between the body fat composition and high sensitive C-reactive protein in Turkish adults.

OBJECTIVES: The adipose tissue is an active immune organ. High sensitive C-reactive protein CRP (hs-CRP) is a strong independent predictor of a possible future myocardial infarction and stroke, and it has also been shown to be related to the subclinical atherosclerosis. The aim of this study was to investigate the relation between the body fat composition, metabolic syndrome, and the hs-CRP plasma levels. METHODS: Total 246 consecutive Turkish subjects, admitted to the internal medicine clinic with the diagnosis of diabetes mellitus, insulin resistance or metabolic syndrome, were included into the study. The total body fat composition was measured in every participant with a commercially available bio-impedance meter. The hs-CRP levels, body composition parameters, and biochemical variables were compared. RESULTS: The hs-CRP levels increased in parallel with the body weight in Turkish subjects. This increase was significant especially in the women. The waist circumference, body mass index (BMI), and body composition variables (visceral fat level, total body fat, and total body muscle mass) were significant correlates of the hs-CRP. The waist circumference and BMI were independent predictors of the hs-CRP. CONCLUSION: The waist circumference, BMI, and body composition variables (visceral fat level, total body fat and total body muscle mass) were significant correlates of the hs-CRP in Turkish adults. Body weight control may account for an important target especially in patients with the metabolic syndrome.

Implantable cardioverter defibrillator pocket infection caused by Klebsiella pneumonia.

Like any other foreign bodies, implanted cardiac devices can become infected. Staphylococcus aureus and coagulase-negative Staphilococci are the most common causes of infections of pacemaker and defibrillator systems. In this case an implantable cardioverter defibrillator pocket infection caused by an extremely rare microorganism, Klebsiella pneumonia, is presented.