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Electrochemical scanning tunneling microscopy (EC-STM) and electrochemical quartz crystal microbalance (E-QCM) techniques in combination with DFT calculations have been applied to reveal the static phase and the phase transition of copper underpotential deposition (UPD) on a gold electrode surface. EC-STM demonstrated, for the first time, the direct visualization of the disintegration of (â3 × â3)R30° copper UPD adlayer with coadsorbed SO42- while changing sample potential (ES) toward the redox Pa2/Pc2 peaks, which are associated with the phase transition between the Cu UPD (â3 × â3)R30° phase II and disordered randomly adsorbed phase III. DFT calculations show that SO42- binds via three oxygens to the bridge sites of the copper with sulfate being located directly above the copper vacancy in the (â3 × â3)R30° adlayer, whereas the remaining oxygen of the sulfate points away from the surface. E-QCM measurement of the change of the electric charge due to Cu UPD Faradaic processes, the change of the interfacial mass due to the adsorption and desorption of Cu(II) and SO42-, and the formation and stripping of UPD copper on the gold surface provide complementary information that validates the EC-STM and DFT results. This work demonstrated the advantage of using complementary in situ experimental techniques (E-QCM and EC-STM) combined with simulations to obtain an accurate and complete picture of the dynamic interfacial adsorption and UPD processes at the electrode/electrolyte interface.
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Nutritional education is pivotal in the medical nutritional therapy of type 2 diabetes mellitus (T2DM). The extended parallel process model (EPPM) is a health education method for inducing desirable health behaviours. The present study aimed to investigate the effect of nutritional education based on the EPPM in T2DM patients on knowledge, attitude, practice, anthropometric indices, glycaemic factors, lipid profile and adherence to the diabetic diet. A randomised, double-blind, controlled, factorial field trial was designed for T2DM patients aged 30-59 years (n 88). Participants were randomly allocated into four groups to receive EPPM-based nutritional education through gain framed message (GFM), loss framed message (LFM), their combination (G\LFM) or usual diabetic education in the control group (CG). Participants were assessed before and after the study duration. After 3 months of intervention, eighty participants finished the study. The EPPM-based intervention increased participants' knowledge, behavioural intention, perceived sensitivity, severity, self-efficacy (P < 0·001 for all) and response efficacy (P = 0·029) in comparison with CG. GFM (P = 0·004) and G\FLM (P = 0·034) reduced carbohydrate intake and LFM (P = 0·034) and G\LFM (P = 0·047) decreased fat intake. Between-group analysis indicated interventions reduced weight (P = 0·046), BMI (P = 0·038), fasting blood sugar (P = 0·030), 2-hour postprandial blood glucose (P = 0·027) and TAG (P = 0·002) in comparison with the CG. Results were NS for protein intake, waist and hip circumference, waist:hip ratio, HbA1c, total cholesterol, LDL and HDL. Nutritional education based on EPPM could increase the knowledge and awareness of T2DM patients. Also, it could be beneficial for blood glucose amendment. Further investigations are recommended.
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Diabetes Mellitus Tipo 2 , Dieta para Diabéticos , Controle Glicêmico , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Masculino , Feminino , Adulto , Controle Glicêmico/métodos , Dieta para Diabéticos/métodos , Educação de Pacientes como Assunto/métodos , Cooperação do Paciente , Glicemia/análise , Glicemia/metabolismoRESUMO
In this work, we designed, fabricated, and characterized the first nitrogen (N)-doped single-crystalline 4H silicon carbide (4H-SiC) electrode for sensing the neurotransmitter dopamine. This N-doped 4H-SiC electrode showed good selectivity for redox reactions of dopamine in comparison with uric acid (UA), ascorbic acid (AA), and common cationic ([Ru(NH3)6]3+), anionic ([Fe(CN)6]3-), and organic (methylene blue) redox molecules. The mechanisms of this unique selectivity are rationalized by the unique negative Si valency and adsorption properties of the analytes on the N-doped 4H-SiC surface. Quantitative electrochemical detection of dopamine by the 4H-SiC electrode was achieved in the linear range from 50 nM to 10 µM with a detection limit of 0.05 µM and a sensitivity of 3.2 nA.µM-1 in a pH = 7.4 phosphate buffer solution. In addition, the N-doped 4H-SiC electrode demonstrated excellent electrochemical stability. This work forms the foundation for developing 4H-SiC as the next-generation robust and biocompatible neurointerface material for a broad range of applications such as the in vivo sensing of neurotransmitters.
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Dopamina , Nitrogênio , Nitrogênio/química , Técnicas Eletroquímicas , Eletrodos , Ácido Ascórbico/químicaRESUMO
In this work, we designed and fabricated Pd/Au bimetallic thin film electrodes with isolated Pd nanoparticles via underpotential deposition of copper on a gold substrate followed by in situ redox replace reaction in a Pd salt solution. The Pd/Au electrode was characterized by AFM and XPS as well as multiple electrochemical techniques including CV and electrochemical quartz crystal microbalance (EQCM) in sulfuric acid and phosphate buffer electrolytes. Results show that the reduction reactions of the analytes (i.e., H2O2 and 3-nitrotyrosine (3-NT)) at the Pd/Au thin film surfaces affect the nature and reactivity of Pd/Au surface electrochemistry including the adsorbed/absorbed hydrogen and/or the premonolayer palladium oxide redox processes at Pd. The EQCM experiment supports the arrangement of small size Pd nanoparticles in the Pd thin film in the presence of gold exhibits unusual properties, acting as a new physicochemical dimension between the electrode and target H2O2 and 3-NT molecules. The Pd/Au thin film was demonstrated as an extremely sensitive and selective probe for detection of common ROS and RNS (i.e., H2O2 and 3-NT). The integration of two different metallic species, Pd and Au, into a surface structure on nanoscale by exploiting their unique surface electrochemistry establishes an innovative analytical method for highly sensitive and selective detection of H2O2 and 3-NT simultaneously. This method has a general scope for detecting a broad range of redox active and nonredox active species simultaneously, which opens up new opportunities to develop new electrocatalytic materials and innovative sensing approaches.
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Coronavirus disease 2019 (COVID-19) vaccines are the most effective tools in managing the pandemic. However, the concern about these vaccines is the occurrence of unwanted adverse events (AEs). This study aimed to evaluate the short-term AEs of COVID-19 vaccines (Sputnik V, Astrazenka, and Sinopharm). A cross-sectional study using an online questionnaire was conducted among 321 vaccinated individuals. Demographic information, history of drug use, prior infection with COVID-19, the type of vaccine, vaccination stage, local injection site complication, systemic complication, and allergic reactions were collected and evaluated. Local complications, including pain and swelling at the injection site, and systemic complications, including fever, fatigue, lethargy, lymphadenopathy, and diarrhea, were reported after the injection of the AstraZeneca vaccine was more than the other 2 vaccines; The prevalence of fatigue and lethargy was higher than other systemic complications. The least reported complication was due to lymphadenopathy. The Sinopharm vaccine showed a lower prevalence of AEs than the other 2. The rare AEs, such as facial paralysis, nasal bleeding, and urticarial, were further reported after injection of the AstraZeneca vaccine. In general, the severity of systemic complications after the second dose of the vaccine was also higher than the first dose. All 3 vaccines were safe and tolerable. The most commonly reported AEs were injection site pain (local) and fatigue and lethargy (systemic). These expected AEs occurred shortly after vaccination and indicated an early immune response after vaccination.
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COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Linfadenopatia , Vacinas , Humanos , Vacinas contra COVID-19/efeitos adversos , Letargia , Estudos Transversais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Fadiga/epidemiologia , Fadiga/etiologia , DorRESUMO
Introduction: The present cross sectional study aimed to evaluate the construct and criterion validity, reliability, and gender and age differences of the 12-item General Health Questionnaire (GHQ-12) among hospitalized patients with COVID-19 in 2020. The criterion validity was assessed via its link with perceived stress, sleep quality, daily life activities, and demographic and medical characteristics. Methods: A total of 328 COVID-19 patients (55.8% men; Mage = 50.49, SD = 14.96) completed the GHQ-12, the Perceived Stress Scale (PSS), the Pittsburgh Sleep Quality Index (PSQI), the Activities of Daily Life (ADL)-Katz Scale, and the Lawton Instrumental Activities of Daily Living Scale (IADL). Results: Among 13 factorial models, the three-factor model (successful coping, self-esteem, and stress) was shown to have the best fit. GHQ-12 was positively associated with PSQI, PSS, Hyperlipidemia, psychiatry disorders, hospitalization duration, the change in sleep time, and use of sleeping pills, and negatively correlated with educational level, and the number of family members. The GHQ-12 also had a negative correlation with ADL and IADL in over 60 years of age group. Females scored higher on total GHQ-12 scores, compared to males. Finally, the hospitalization duration was longer for patients over 60 (mean = 8.8 days, SD = 5.9) than patients under 60 (mean = 6.35 days, SD = 5.87). Discussion: Overall, the findings provided evidence that mental distress in patients with COVID-19 is correlated with high perceived stress, low sleep quality, low ADL and IADL, and a range of demographic features and medical conditions. Designing psychological interventions for these patients that target the aforementioned correlates of mental distress is warranted.
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Background: Since 2019, Coronavirus has been a highly contagious disease. The COVID-19 outbreak was declared a pandemic by the World Health Organization in March 2020. Variable laboratory findings are reported in COVID-19 patients, among which elevated levels of D-dimer, lactate dehydrogenase, as well as lymphopenia, have been reported to be associated with increased severity of disease symptoms requiring ventilator support, intensive care unit admission, and mortality. Materials and Methods: In the current study, inclusion criteria were: patient age above 18 years and hospitalization in the Imam Khomeini hospital with COVID-19 disease confirmed with nasopharyngeal swab polymerase chain reaction tests. Levels of white blood cells, neutrophils, lymphocytes, hemoglobin, platelets, D-dimer, C-reactive protein, LDH, and ferritin were measured and their correlation with the final patients' outcome was evaluated. Results: A total of 208 patients were included in the present study. Higher neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte, LDH, platelet to lymphocyte ratio, ferritin, and D-dimer were significantly related to O2 dependency. Neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte and LDH were significantly related to higher rates of mortality. Higher Hb and lymphocyte count were significantly related to higher rates of survival. Conclusion: Hematological parameters including neutrophil to lymphocyte ratio, (WBC count excluding lymphocyte)/lymphocyte, LDH, platelet to lymphocyte ratio, ferritin, D-dimer, Hb, and lymphocyte count were significantly related to the prognosis of patients with COVID-19 disease. This could help decide which COVID-19 patients have priority for hospitalization and intensive medical care, particularly when the pandemic disease causes limitations in healthcare service.
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[This corrects the article DOI: 10.3389/fpsyg.2023.1132154.].
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Background and Purpose: Oropharyngeal candidiasis is the most prevalent opportunistic fungal infection in patients with human immunodeficiency virus (HIV) as well as other immunodeficiency disorders, which is caused by various Candida species, mostly Candida albicans. Studies have shown that Candida isolates differ in their pathogenicity. These variations are attributed to virulence factors, host characteristics, and the target tissue. This study aimed to determine and compare the secretion of hydrolytic enzymes in C. albicans and non-albicans Candida species isolated from HIV+/AIDS patients and healthy individuals. Materials and Methods: Samples were taken from 201 patients with HIV and 118 healthy individuals. The samples were identified by macroscopic, phenotypic, and molecular methods, and virulence factors were subsequently measured. Statistical differences in enzymatic activity of various Candida isolates were calculated (P<0.0001). Results: In total, 95 samples (47.20%) from patients and 46 samples (38.90%) from healthy individuals were positive for the growth of different Candida species. There were 39 (41.10%) and 36 (78.30%) C. albicans in patients and healthy individuals, respectively, as well as 56 (58.90%) and 10 (21.70%) non-albicans species in patients and healthy subjects, respectively. All the enzymes produced by Candida species enzymes were at low, medium, and high levels. Hemolysin activity in Candida species isolated from patients was significantly higher, compared to healthy individuals. Moreover, the activity of all C. albicans enzymes in patients was significantly higher than other Candida species. Conclusion: The C. albicans isolated from HIV-positive individuals secreted higher amounts of exoenzymes, and can cause oropharyngeal candidiasis and become a source of candidiasis for the host.
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In this study 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonic acid (DOTMP) was used as the polyaminophosphonic acid carrier ligand and the therapeutic potential of the bone seeking radiopharmaceutical (47)Sc-DOTMP was assessed by measuring its dosage-dependent skeletal uptake and then the absorbed radiation dose of human organs was estimated. Because of limited availability of (47)Sc we performed some preliminary studies using (46)Sc. (46)Sc was produced with a specific activity of 116.58 MBq/mg (3.15 mCi/mg) and radionuclide purity of 98%. (46)Sc-DOTMP was prepared and an activity of 1.258 MBq (34 µCi) at a chelant-to-metal ratio of 60:1 was administered to five groups of mice with each group containing 3 mice that were euthanized at 4, 24, 48, 96 and 192 h post administration. The heart, lungs, liver, spleen, kidneys, intestine, skin, muscle, and a femur were excised, weighed, and counted. The data were analyzed to determine skeletal uptake and source organ residence times and cumulated activities for (47)Sc-DOTMP. (46)Sc-DOTMP complex was prepared in radiochemical purity about 93%. In vitro stability of complex was evaluated at room temperature for 48 h. Biodistribution studies of complex in mice were studied for 7 days. The data were analyzed to estimate skeletal uptake and absorbed radiation dose of human organs using biodistribution data from mice. By considering the results, (47)Sc-DOTMP is a possible therapeutic agent for using in palliation of bone pain due to metastatic skeletal lesions from several types of primary cancers in prostate, breast, etc.
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Skin disorders comprise more than 35% of all occupationally related diseases. 90-95% of work-related dermatoses are contact dermatitis. Effects of occupational dermatitis in the lives of workers are substantial. To plan any preventive program we need basic statistics of the problem, that we had no reliable one which includes a lot of industries in Iran. Therefore we decided to determine occupational contact dermatitis, and it's subtypes prevalence in various jobs. The objective of this study is determination of occupational contact dermatitis, and it's subtypes prevalence and comparison among various jobs. In this cross -sectional study, we examined 3061 workers of various industries during 2007-2012 and recognized contact dermatitis cases. Irritant and allergic cases were separated according to clinical judgment of physician and patch test using European standard series. We found 271 (prevalence=8.8%) occupational contact dermatitis cases which 247 (91.1%) were irritant, and the rest were allergic. The highest prevalence was in washing powder production and then glaze and paint workers, mechanists and chemical workers were located. There is a great variability for occupational contact dermatitis in various industries and between different countries. These statistics changes during the time by changing in number of workers and their characteristics, variation in material and process and glove use situation. So every country must have a national data bank of occupational contact dermatitis, which must be updated after a period of time.