Frontal QRS-T angle in patients with the suspicion of Coronavirus disease 2019 (COVID-19): could it be used as a predictive gravity sign even before the diagnosis by PCR?

OBJECTIVE: Coronavirus disease 2019 (COVID-19) has been an ongoing global public health concern, causing serious challenges in diagnosing the disease timely. We investigated the value of the frontal QRS-T (fQRS-T) angle in patients visiting the emergency department with the suspicion of COVID-19. PATIENTS AND METHODS: A hundred and thirty-seven patients with the complaint of dyspnea were evaluated retrospectively. The patients with a history of coronary artery disease, heart failure, pulmonary disease, hypertension, diabetes mellitus, or using any medication such as heart rate controllers or antiarrhythmic drugs were excluded from the study. The angle between frontal QRS- and T-wave axis was defined as the fQRS-T angle, and the patients were divided into two groups based on the fQRS-T angle (group 1, <90° and group 2, ≥90°). Demographic, clinical, electrocardiographic data and rRT-PCR results were compared between the groups. RESULTS: The mean value of the fQRS-T angle of all participants was 45.26°. There was no significant difference between the groups according to the demographic and clinical data. Subjects with wider fQRS-T angle (group 2) had higher heart rates (p = 0.018), higher corrected QT values (p = 0.017), and higher QRS axis (p = 0.001). The patients in group 2 had a higher number of positive COVID-19 rRT-PCR test results compared to subjects with the normal fQRS-T angle (p = 0.002). In multivariate regression analysis, fQRS-T angle (p = 0.027, OR: 1.013, 95% CI: 1.001-1.024) was found as an independent variable affecting the PCR test results. CONCLUSIONS: Prompt diagnosis, initiating preventive and protective measures in an early stage of COVID-19 are crucial. In suspected COVID-19 infection, the use of faster-resulting tests and diagnostic tools for COVID-19 allows patients to be diagnosed and treated in a timely manner for recovery, thereby optimizing patient management. Therefore, the fQRS-T angle can be used in patients with dyspnea as a part of diagnostic scores of COVID-19, even before the rRT-PCR test results and overt disease.

Prevalence of vitamin D insufficiency in children with forearm fractures.

PURPOSE: This study aimed to determine whether children with distal radius impaction fractures have increased prevalence of 25-hydroxyvitamin D (25(OH) D) insufficiency compared with healthy controls. PATIENTS AND METHODS: This is a prospective controlled study. The 30 children who were diagnosed with forearm fracture at the orthopaedic emergency clinic were included in the study and 30 healthy children from the routine paediatric outpatient unit were included as the control group. Peripheric venous 25(OH) D, calcium (Ca), magnesium (Mg), phosphor (P), alkaline phosphatase (ALP) and parathyroid hormone (PTH) of both groups were recorded. The sample size was estimated based on the effect size for a type I error of 5% and power of 80%. RESULTS: Demographic characteristics of the two groups did not differ in terms of weekly physical activity levels and breast milk intake. The mean whole body BMI was similar in both groups of patients. History of previous fracture and 25(OH) D level were significantly lower in the patient group than the control group. CONCLUSION: In the present study, the prevalence of vitamin D insufficiency or deficiency was higher in patients with forearm impaction type fractures than healthy controls and the baseline levels reported in the literature. In addition, there were no significant differences in serum Ca, Mg, P, ALP and PTH levels between the healthy controls and the patient group.

Cellulose nanocrystals as templates for cetyltrimethylammonium bromide mediated synthesis of Ag nanoparticles and their novel use in PLA films.

In the present paper, we reported how cellulose nanocrystals (CNC) from microcrystalline cellulose have the capacity to assist in the synthesis of metallic nanoparticles chains. A cationic surfactant, cetyltrimethylammonium bromide (CTAB), was used as modifier for CNC surface. Silver nanoparticles were synthesized on CNC, and nanoparticle density and size were optimized by varying concentrations of nitrate and reducing agents, and the reduction time. The experimental conditions were optimized for the synthesis and the resulting Ag grafted CNC (Ag-g-CNC) were characterized by means of TGA, SEM, FTIR and XRD, and then introduced in PLA matrix. PLA nanocomposite containing silver grafted cellulose nanocrystals (PLA/0.5Ag-g-1CNC) was characterized by optical and thermal analyses and the obtained data were compared with results from PLA nanocomposites containing 1% wt. of CNC (PLA/1CNC), 0.5% wt. of silver nanoparticles (PLA/0.5Ag) and hybrid system containing CNC and silver in the same amount (PLA/1CNC/0.5Ag). The results demonstrated that grafting of silver nanoparticles on CNC positively affected the thermal degradation process and cold crystallization processes of PLA matrix. Finally, the antibacterial activity of the different systems was studied at various incubation times and temperatures, showing the best performance for PLA/1CNC/0.5Ag based nanocomposite.

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.

Higher red cell distribution width values are associated with impaired exercise capacity during exercise treadmill testing in patients without obstructive coronary disease: a preliminary study.

BACKGROUND: Red cell distribution width (RDW) is associated with poor cardiovascular outcomes. We aimed to find out if this association could be explained by impaired exercise capacity in patients without obstructive coronary artery disease (CAD). PATIENTS AND METHODS: The patients who underwent exercise treadmill test (ETT) who have non-obstructive CAD and were free of heart failure symptoms were evaluated. Total of 132 patients were enrolled, and patients were divided into three groups according to their Metabolic Equivalent Task (MET) level measured by exercise treadmill test (ETT): Less than 7 METs (group 1), 7-10 METs (group 2) and greater than 10 METs (group 3). RESULTS: The patients in Group 1 had significantly higher RDW levels (16.46 ± 2.79) compared to Group 2 (15.05 ± 2.03) and Group 3 (14.52 ± 1.37), independent of hemoglobin and hematocrit values. Significant differences for age, gender, duration of ETT and Duke Treadmill Score were also found in proportion to the reduced exercise capacity. In multivariate analysis, only duration of ETT (ß = 1.017, p = < 0.001) and RDW (ß = 0.040, p = 0.026) were found as independent variables, which had statistically significant effects on METs. CONCLUSIONS: We found an independent association between RDW and exercise capacity in patients free of obstructive coronary disease suggesting that patients with elevated RDW values are expected to have impaired exercise capacity.

Increased sympathetic activation in patients with vasovagal syncope is associated with higher mean platelet volume levels.

OBJECTIVES: Vasovagal syncope (VVS) is supposed to be modulated by increased sympathetic tone following an orthostatic maneuver. Increased sympathetic activity may have an important role in mean platelet volume (MPV), either by peripheral activation or by effects on thrombocytopoiesis. We aimed to show the effects of increased sympathetic activity on platelet size in patients with VVS in the present study. PATIENTS AND METHODS: Thirty-seven patients with VVS were compared with age- and sex-matched 33 patients without VVS. All patients have undergone 24 hour holter monitoring for heart rate variability (HRV) and time-domain HRV analysis. Blood samples for MPV measurements were taken before 24 hour holter monitoring. RESULTS: Group 1 was consisted of 37 patients with VVS and group 2 was consisted of 33 patients without VVS. We observed that SDNN, SDNN index, SDSD, RMSDD, PNN50 count were significantly lower and MPV was found significantly higher in patients with VVS (p < 0.05 for all). Pearson's correlation analysis showed that MPV was moderately negatively correlated with SDNN (r = -0.421), SDSD (r = -0.396), NN50 count (r = -0.395) and RMSDD (r = -0.393). Multivariate regression analysis showed that SDNN was the only independent variable, which had a significant effect on increased MPV level (ß = -0.295 , p = 0.016). CONCLUSIONS: We found that MPV was closely associated with increased sympathetic activity in patients with VVS. Our analysis supports the hypothesis that alterations in autonomic status might play a role in the development of platelet size.