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1.
Epilepsia Open ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38790148

RESUMO

OBJECTIVE: In epilepsy, early diagnosis, accurate determination of epilepsy type, proper selection of antiseizure medication, and monitoring are all essential. However, despite recent therapeutic advances and conceptual reconsiderations in the classification and management of epilepsy, serious gaps are still encountered in day-to-day practice in Egypt as well as several other resource-limited countries. Premature mortality, poor quality of life, socio-economic burden, cognitive problems, poor treatment outcomes, and comorbidities are major challenges that require urgent actions to be implemented at all levels. In recognition of this, a group of Egyptian epilepsy experts met through a series of consecutive meetings to specify the main concepts concerning the diagnosis and management of epilepsy, with the ultimate goal of establishing a nationwide Egyptian consensus. METHODS: The consensus was developed through a modified Delphi methodology. A thorough review of the most recent relevant literature and international guidelines was performed to evaluate their applicability to the Egyptian situation. Afterward, several remote and live rounds were scheduled to reach a final agreement for all listed statements. RESULTS: Of 278 statements reviewed in the first round, 256 achieved ≥80% agreement. Live discussion and refinement of the 22 statements that did not reach consensus during the first round took place, followed by final live voting then consensus was achieved for all remaining statements. SIGNIFICANCE: With the implementation of these unified recommendations, we believe this will bring about substantial improvements in both the quality of care and treatment outcomes for persons with epilepsy in Egypt. PLAIN LANGUAGE SUMMARY: This work represents the efforts of a group of medical experts to reach an agreement on the best medical practice related to people with epilepsy based on previously published recommendations while taking into consideration applicable options in resource-limited countries. The publication of this document is expected to minimize many malpractice issues and pave the way for better healthcare services on both individual and governmental levels.

2.
Diagnostics (Basel) ; 14(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38667483

RESUMO

Systemic vasculitides are a rare and complex group of diseases that can affect multiple organ systems. Clinically, presentation may be vague and non-specific and as such, diagnosis and subsequent management are challenging. These entities are typically classified by the size of vessel involved, including large-vessel vasculitis (giant cell arteritis, Takayasu's arteritis, and clinically isolated aortitis), medium-vessel vasculitis (including polyarteritis nodosa and Kawasaki disease), and small-vessel vasculitis (granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis). There are also other systemic vasculitides that do not fit in to these categories, such as Behcet's disease, Cogan syndrome, and IgG4-related disease. Advances in medical imaging modalities have revolutionized the approach to diagnosis of these diseases. Specifically, color Doppler ultrasound, computed tomography and angiography, magnetic resonance imaging, positron emission tomography, or invasive catheterization as indicated have become fundamental in the work up of any patient with suspected systemic or localized vasculitis. This review presents the key diagnostic imaging modalities and their clinical utility in the evaluation of systemic vasculitis.

3.
J Cardiovasc Dev Dis ; 11(4)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38667736

RESUMO

Cardiac amyloidosis (CA) is an underdiagnosed form of infiltrative cardiomyopathy caused by abnormal amyloid fibrils deposited extracellularly in the myocardium and cardiac structures. There can be high variability in its clinical manifestations, and diagnosing CA requires expertise and often thorough evaluation; as such, the diagnosis of CA can be challenging and is often delayed. The application of artificial intelligence (AI) to different diagnostic modalities is rapidly expanding and transforming cardiovascular medicine. Advanced AI methods such as deep-learning convolutional neural networks (CNNs) may enhance the diagnostic process for CA by identifying patients at higher risk and potentially expediting the diagnosis of CA. In this review, we summarize the current state of AI applications to different diagnostic modalities used for the evaluation of CA, including their diagnostic and prognostic potential, and current challenges and limitations.

4.
Heliyon ; 10(7): e28725, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596026

RESUMO

Environmental monitoring, ocean research, and underwater exploration are just a few of the marine applications that require precise underwater target localization. This study goes into the field of underwater target localization using Recurrent Neural Networks (RNNs) enhanced with proximity-based approaches, with a focus on mean estimation error as a performance metric. In complex and dynamic underwater environments, conventional localization systems frequently face challenges such as signal degradation, noise interference, and unstable hydrodynamic conditions. This paper presents a novel approach to employing RNNs to increase the accuracy of underwater target localization by exploiting the temporal dynamics of proximity-informed data. This method uses an RNN architecture to track changes in audio emissions from underwater targets sensed by a microphone network. Using the temporal correlations represented in the data, the RNN learns patterns indicative of target localization quickly and correctly. Furthermore, the addition of proximity-based features increases the model's ability to understand the relative distances between hydrophone nodes and the target, resulting in more accurate localization estimates. To evaluate the suggested methodology, thorough simulations and practical experiments were carried out in a variety of underwater environments. The results show that the RNN-based strategy beats conventional methods and works effectively even in difficult settings. The utility of the proximity-aware RNN model is demonstrated, in particular, by considerable reductions in the mean estimate error (MEE), an important performance measure.

5.
J Cardiovasc Dev Dis ; 11(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535118

RESUMO

Cardiac allograft vasculopathy (CAV) is a distinct form of coronary artery disease that represents a major cause of death beyond the first year after heart transplantation. The pathophysiology of CAV is still not completely elucidated; it involves progressive circumferential wall thickening of both the epicardial and intramyocardial coronary arteries. Coronary angiography is still considered the gold-standard test for the diagnosis of CAV, and intravascular ultrasound (IVUS) can detect early intimal thickening with improved sensitivity. However, these tests are invasive and are unable to visualize and evaluate coronary microcirculation. Increasing evidence for non-invasive surveillance techniques assessing both epicardial and microvascular components of CAV may help improve early detection. These include computed tomography coronary angiography (CTCA), single-photon emission computed tomography (SPECT), positron emission tomography (PET), and vasodilator stress myocardial contrast echocardiography perfusion imaging. This review summarizes the current state of diagnostic modalities and their utility and prognostic value for CAV and also evaluates emerging tools that may improve the early detection of this complex disease.

6.
Biomedicines ; 12(3)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38540296

RESUMO

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy. It follows an autosomal dominant inheritance pattern in most cases, with incomplete penetrance and heterogeneity. It is familial in 60% of cases and most of these are caused by pathogenic variants in the core sarcomeric genes (MYH7, MYBPC3, TNNT2, TNNI3, MYL2, MYL3, TPM1, ACTC1). Genetic testing using targeted disease-specific panels that utilize next-generation sequencing (NGS) and include sarcomeric genes with the strongest evidence of association and syndrome-associated genes is highly recommended for every HCM patient to confirm the diagnosis, identify the molecular etiology, and guide screening and management. The yield of genetic testing for a disease-causing variant is 30% in sporadic cases and up to 60% in familial cases and in younger patients with typical asymmetrical septal hypertrophy. Genetic testing remains challenging in the interpretation of results and classification of variants. Therefore, in 2015 the American College of Medical Genetics and Genomics (ACMG) established guidelines to classify and interpret the variants with an emphasis on the necessity of periodic reassessment of variant classification as genetic knowledge rapidly expands. The current guidelines recommend focused cascade genetic testing regardless of age in phenotype-negative first-degree relatives if a variant with decisive evidence of pathogenicity has been identified in the proband. Genetic test results in family members guide longitudinal clinical surveillance. At present, there is emerging evidence for genetic test application in risk stratification and management but its implementation into clinical practice needs further study. Promising fields such as gene therapy and implementation of artificial intelligence in the diagnosis of HCM are emerging and paving the way for more effective screening and management, but many challenges and obstacles need to be overcome before establishing the practical implications of these new methods.

7.
J Imaging ; 10(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38392086

RESUMO

Exposure to high altitude results in hypobaric hypoxia, leading to physiological changes in the cardiovascular system that may result in limiting symptoms, including dyspnea, fatigue, and exercise intolerance. However, it is still unclear why some patients are more susceptible to high-altitude symptoms than others. Hypoxic simulation testing (HST) simulates changes in physiology that occur at a specific altitude by asking the patients to breathe a mixture of gases with decreased oxygen content. This study aimed to determine whether the use of transthoracic echocardiography (TTE) during HST can detect the rise in right-sided pressures and the impact of hypoxia on right ventricle (RV) hemodynamics and right to left shunts, thus revealing the underlying causes of high-altitude signs and symptoms. A retrospective study was performed including consecutive patients with unexplained dyspnea at high altitude. HSTs were performed by administrating reduced FiO2 to simulate altitude levels specific to patients' history. Echocardiography images were obtained at baseline and during hypoxia. The study included 27 patients, with a mean age of 65 years, 14 patients (51.9%) were female. RV systolic pressure increased at peak hypoxia, while RV systolic function declined as shown by a significant decrease in the tricuspid annular plane systolic excursion (TAPSE), the maximum velocity achieved by the lateral tricuspid annulus during systole (S' wave), and the RV free wall longitudinal strain. Additionally, right-to-left shunt was present in 19 (70.4%) patients as identified by bubble contrast injections. Among these, the severity of the shunt increased at peak hypoxia in eight cases (42.1%), and the shunt was only evident during hypoxia in seven patients (36.8%). In conclusion, the use of TTE during HST provides valuable information by revealing the presence of symptomatic, sustained shunts and confirming the decline in RV hemodynamics, thus potentially explaining dyspnea at high altitude. Further studies are needed to establish the optimal clinical role of this physiologic method.

8.
Sensors (Basel) ; 24(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38339445

RESUMO

Currently, in modern wind farms, the doubly fed induction generator (DFIG) is commonly adopted for its ability to operate at variable wind speeds. Generally, this type of wind turbine is controlled by using two converters, one on the rotor side (RSC) and the other one on the grid side (GSC). However, the control of these two converters depends mainly on current sensors measurements. Nevertheless, in the case of sensor failure, control stability may be compromised, leading to serious malfunctions in the wind turbine system. Therefore, in this article, we will present an innovative diagnostic approach to detect, locate, and isolate the single and/or multiple real-phase current sensors in both converters. The suggested approach uses an extended Kalman filter (EKF) bank structured according to a generalized observer scheme (GOS) and relies on a nonlinear model for the RSC and a linear model for the GSC. The EKF estimates the currents in the converters, which are then compared to sensor measurements to generate residuals. These residuals are then processed in the localization, isolation, and decision blocks to precisely identify faulty sensors. The obtained results confirm the effectiveness of this approach to identify faulty sensors in the abc phases. It also demonstrates its ability to overcome the nonlinearity induced by wind fluctuations, as well as resolves the coupling issue between currents in the fault period.

9.
Arthroscopy ; 40(4): 1108-1116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37716634

RESUMO

PURPOSE: To study the prevalence and quality of application of minimal clinically important difference (MCID), substantial clinical benefit (SCB), patient-acceptable symptomatic state (PASS), and maximum outcome improvement (MOI), reported in the orthopaedic sports medicine knee and shoulder literature in recent years and to bring awareness of proper use of such metrics. METHODS: A literature review of all shoulder and knee articles published from the American Journal of Sports Medicine (AJSM), Journal of Shoulder and Elbow Surgery (JSES), and Arthroscopy from 2016 to 2020 was performed, specifically investigating whether MCID, SCB, PASS, or MOI were used or reported. Additionally, the way these metrics were reported and interpreted was recorded. RESULTS: Out of 5,039 studies, 889 shoulder and knee studies met the inclusion criteria. Overall, 16.7% reported either MCID, PASS, or SCB. MCID was the most reported across all 3 journals. MCID was reported 12.4% of the time throughout the 5 years. PASS was reported 3.2% and SCB 1.1% of the time over the 5 years. MOI was not reported by any of the journals during this period. There was a statistically significant increase in MCID reporting in 2 of the 3 journals over the 5-year course, Arthroscopy (P = .02) and AJSM (P = .05). There was no statistically significant increase in PASS or SCB reporting rates in all 3 journals. Only 39.1% of studies reported MCID correctly (i.e., defined as the number of individual patients meeting MCID/total patients in the study). CONCLUSIONS: This study shows an increasing trend in the use of clinically significant outcome metrics, such as MCID, for interpretation of patient-reported outcomes; however, these individual metrics are often not being used on the individual level and subsequently not reported accurately. We recommend determining whether the specific metric met the threshold per individual patient and then reporting those as a percentage of the sample population to achieve the full potential of these metrics and translate them accurately across various studies. CLINICAL RELEVANCE: As the usage of clinically significant outcome metrics rises, so does the need for accurate reporting. These findings will encourage future studies to follow a more standardized format.


Assuntos
Ortopedia , Ombro , Humanos , Resultado do Tratamento , Prevalência , Atividades Cotidianas , Diferença Mínima Clinicamente Importante , Medidas de Resultados Relatados pelo Paciente , Estudos Retrospectivos
10.
Healthcare (Basel) ; 11(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38063619

RESUMO

COVID-19 vaccine acceptance and refusal vary across countries and among different socio-demographic groups. This study investigates hesitancy related to the COVID-19 vaccine and the associated factors in the rural-community-dominated Jazan Province, Saudi Arabia. A cross-sectional study through an online questionnaire was conducted from February to April 2021 to investigate the extent of vaccine hesitancy related to the COVID-19 vaccine and the associated factors in the Jazan region. A Chi-squared test and post hoc analysis were conducted to analyze the statistical significance of the association between variables. Of the 569 participants who completed the online questionnaire, the majority were males (81.5%) and had a university education (72.6%). Of the participants, more than one-third (36.9%) were hesitant to vaccinate. Concern about adverse side effects following vaccination was the most reported reason for vaccine hesitancy (42.6%), followed by beliefs that the vaccine was unsafe or ineffective (15.5%). The data analysis revealed that people who lived in cities in Jazan Province or those who did not have a family history of COVID-19 infection were more likely to be vaccine hesitant. It is more important than ever to develop and implement community-based strategies to address vaccine hesitancy, especially in rural areas.

11.
J Imaging ; 9(11)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37998083

RESUMO

Chest radiography (CXR) is the most frequently performed radiological test worldwide because of its wide availability, non-invasive nature, and low cost. The ability of CXR to diagnose cardiovascular diseases, give insight into cardiac function, and predict cardiovascular events is often underutilized, not clearly understood, and affected by inter- and intra-observer variability. Therefore, more sophisticated tests are generally needed to assess cardiovascular diseases. Considering the sustained increase in the incidence of cardiovascular diseases, it is critical to find accessible, fast, and reproducible tests to help diagnose these frequent conditions. The expanded focus on the application of artificial intelligence (AI) with respect to diagnostic cardiovascular imaging has also been applied to CXR, with several publications suggesting that AI models can be trained to detect cardiovascular conditions by identifying features in the CXR. Multiple models have been developed to predict mortality, cardiovascular morphology and function, coronary artery disease, valvular heart diseases, aortic diseases, arrhythmias, pulmonary hypertension, and heart failure. The available evidence demonstrates that the use of AI-based tools applied to CXR for the diagnosis of cardiovascular conditions and prognostication has the potential to transform clinical care. AI-analyzed CXRs could be utilized in the future as a complimentary, easy-to-apply technology to improve diagnosis and risk stratification for cardiovascular diseases. Such advances will likely help better target more advanced investigations, which may reduce the burden of testing in some cases, as well as better identify higher-risk patients who would benefit from earlier, dedicated, and comprehensive cardiovascular evaluation.

12.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003307

RESUMO

The aac(6')-Ib gene is the most widespread gene encoding aminoglycoside-modifying enzyme and conferring resistance to tobramycin, streptomycin and kanamycin. The variant aac(6')-Ib-cr gene confers resistance to both aminoglycosides and fluoroquinolones (FQ). A total of 132 Campylobacter isolates, including 91 C. jejuni and 41 C. coli, were selected from broiler hens isolates. The aac(6')-Ib gene was amplified using PCR and was subsequently digested with the BtsCI restriction enzyme to identify aac(6')-Ib-cr. Among these isolates, 31 out of 41 C. coli (75.6%) and 1 (0.98%) C. jejuni were positive for the aac(6')-Ib gene, which was identified as the aac(6')-Ib-cr variant in 10 (32.25%) C. coli isolates. This variant was correlated with mutations in gyrA (Thr-86-Ile), as well as resistance to FQs. This study is the first report in Tunisia on Campylobacter coli strains harboring both the aac(6')-Ib and aac(6')-Ib-cr variants. These genes were present in Campylobacter isolates exhibiting resistance to multiple antibiotics, which restricts the range of available treatments.


Assuntos
Campylobacter coli , Fluoroquinolonas , Animais , Feminino , Fluoroquinolonas/farmacologia , Escherichia coli/genética , Campylobacter coli/genética , Galinhas , Tunísia , Antibacterianos/farmacologia , Mutação , Aminoglicosídeos/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/genética
13.
Acute Crit Care ; 38(2): 217-225, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37313668

RESUMO

BACKGROUND: Polytrauma from road accidents is a common cause of hospital admissions and deaths, frequently leading to acute kidney injury (AKI) and impacting patient outcomes. METHODS: This retrospective, single-center study included polytrauma victims with an Injury Severity Score (ISS) >25 at a tertiary healthcare center in Dubai. RESULTS: The incidence of AKI in polytrauma victims is 30.5%, associated with higher Carlson comorbidity index (P=0.021) and ISS (P=0.001). Logistic regression shows a significant relationship between ISS and AKI (odds ratio [OR], 1.191; 95% confidence interval [CI], 1.150-1.233; P<0.05). The main causes of trauma-induced AKI are hemorrhagic shock (P=0.001), need for massive transfusion (P<0.001), rhabdomyolysis (P=0.001), and abdominal compartment syndrome (ACS; P<0.001). On multivariate logistic regression AKI can be predicated by higher ISS (OR, 1.08; 95% CI, 1.00-1.17; P=0.05) and low mixed venous oxygen saturation (OR, 1.13; 95% CI, 1.05-1.22; P<0.001). The development of AKI after polytrauma increases length of stay (LOS)-hospital (P=0.006), LOS-intensive care unit (ICU; P=0.003), need for mechanical ventilation (MV) (P<0.001), ventilator days (P=0.001), and mortality (P<0.001). CONCLUSIONS: After polytrauma, the occurrence of AKI leads to prolonged hospital and ICU stays, increased need for mechanical ventilation, more ventilator days, and a higher mortality rate. AKI could significantly impact their prognosis.

14.
Ann Hematol ; 102(8): 2033-2038, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37145323

RESUMO

Primary immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia in the absence of other disorders. Vitamin D (VD) has been shown to modulate the immune system and its deficiency is linked to many immunological disorders. Supplementation with VD in ITP has promising results. This work aims at evaluating VD values in children with persistent and chronic ITP and the effect of its deficiency on disease severity and treatment response. A case-control study including 50 persistent and chronic ITP patients and 50 healthy controls was conducted. 25 OH vitamin D level was determined using ELISA technique. VD median value was significantly higher among the control group than that of the patients' group (28 vs 21.5 and p = 0.002). Severe deficiency was detected significantly more among the patients' group than the control group (12 (24%) vs 3 (6%), p = 0.048) respectively. Forty-four percent of complete responders belong to sufficient VD category ((15/34) ~ 44% (p = 0.005)) representing all patients with sufficient VD status (n = 15). Also, a positive correlation between serum level of vitamin D and mean PLT count was observed (r = 0.316, p value = 0.025). Sufficient vitamin D was associated with better treatment response and less disease severity. Vitamin D supplementation may be a new therapeutic option for chronic ITP.


Assuntos
Púrpura Trombocitopênica Idiopática , Deficiência de Vitamina D , Humanos , Criança , Vitamina D/uso terapêutico , Deficiência de Vitamina D/tratamento farmacológico , Estudos de Casos e Controles , Púrpura Trombocitopênica Idiopática/tratamento farmacológico
15.
J Adv Pharm Technol Res ; 14(2): 142-146, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255867

RESUMO

The aim was to analyze the influence of the incorporation of 4% by mass of colloidal dispersion of titanium dioxide (TiO2) nanoparticles on the long-term water sorption and solubility of two commercial universal bonding agents. In vitro studies. A colloidal dispersion of TiO2 nanoparticles was formulated and blended into two commercial dental bonding agents, i.e., Ambar Universal (FGM, Brasil) and G-Premio Bond Universal (GC, America) at 4% by mass. Forty bonding agent discs were fabricated and segregated into four bonding agent groups of 10 discs each, i.e., GA: Ambar Universal (control), GB: Ambar Universal (4% TiO2 incorporated), GC: G-Premio Bond universal (control), and GD: G-Premio Bond (4% TiO2 incorporated). The bonding agent discs were developed by dispensing the bonding agents into a silicone cast of 5 mm diameter and 1 mm depth. After bonding agent discs were desiccated, the cured discs were weighed and kept in distilled water to be evaluated for water sorption and solubility over 1 year storage period. Statistical analysis was performed by independent variable t-test performed using the IBM SPSS software (Chicago, IL: SPSS Inc). The incorporated bonding agent groups (GA and GB) showed significantly lower (P < 0.05) water sorption and solubility following 1 year of water storage in comparison to the control bonding agents. Both GC and GD demonstrated remarkably lower water sorption and solubility than GA and GB. Incorporation of the colloidal dispersion of TiO2 nanoparticles at 4% by mass into the universal bonding agents has significantly reduced their water sorption and solubility contrast to their control groups.

16.
Viruses ; 15(4)2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37112992

RESUMO

The role of dogs as reservoir hosts for Toscana virus (TOSV) remains undetermined. This study investigated TOSV and Leishmania infantum infections in one healthy and three infected dogs with Leishmania (A, B, C) following natural exposition to sandfly bites in a focus of zoonotic visceral leishmaniasis (ZVL) located in Northern Tunisia from June to October 2020. At the end of the exposition period, infected and healthy dogs were examined for TOSV and L. infantum infections by xenodiagnosis using a colony of Phlebotomus perniciosus. Pools of freshly engorged P. perniciosus at days 0 and those at days 7 post-feeding were screened for TOSV and L. infantum by nested PCR in the polymerase gene and kinetoplast minicircle DNA, respectively. In the exposure site, P. pernicious is the most abundant sandfly species. The infection rates of sandflies with TOSV and L. infantum were 0.10 and 0.05%, respectively. Leishmania infantum DNA and TOSV RNA were detected in P. perniciosus females fed on dog B and C, respectively. The isolation of TOSV in Vero cells was achieved from two pools containing P. perniciosus fed on dog C. No pathogens were detected in P. perniciosus females fed on dog A and on control dog. We report for the first time the reservoir competence of dog with ZVL in the transmission of TOSV to sandfly vectors in natural settings, in addition to its role as a main reservoir host of L. infantum.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Leishmaniose , Phlebotomus , Psychodidae , Vírus da Febre do Flebótomo Napolitano , Feminino , Chlorocebus aethiops , Cães , Animais , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Vírus da Febre do Flebótomo Napolitano/genética , Leishmania infantum/genética , Tunísia/epidemiologia , Células Vero , Phlebotomus/genética , DNA , Doenças do Cão/epidemiologia
17.
Molecules ; 28(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36985781

RESUMO

A novel amperometric sensor for the direct determination of toxic mercury ions, Hg2+, based on the organic chelator ionophore N, N di (2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde) benzene-1,2-diamine (NDBD), and multiwalled carbon nanotubes (MWCNT) immobilized on a glassy carbon electrode surface was developed. The parameters influencing sensor performance including the ionophore concentration, the applied potential, and electrolyte pH were optimized. The sensor response to Hg2+ was linear between 1-25 µM with a limit of detection of 60 nM. Interferences from other heavy metal ions were evaluated and the sensor showed excellent selectivity towards Hg2+. The method was successfully applied to the determination of mercury ions in milk and water samples.

18.
BMC Neurol ; 23(1): 110, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932355

RESUMO

BACKGROUND: Previous studies in headache patients measured the cerebrovascular reactivity (CVR) in response to photic stimulation but they have yielded contradictory results. The purpose of study was to measure CVR of both migraine and chronic tension headache (TTH) patients in response to photic stimulation. METHODS: The study included 37 migraineurs and 24 chronic TTH patients compared with 50 age- and sex-matched healthy volunteers. Peak systolic, end diastolic, mean flow velocities and CVR (PSV, EDV, MFV, and CVR) were measured using TCD ultrasonography of the middle, anterior, posterior cerebral and vertebral arteries (MCA, ACA, PCA, and VA) before and after 100 s of 14 Hz photic stimulation. RESULTS: A three-way repeated measures ANOVA interaction with main factors of Vessels (MCA, ACA, PCA, VA), Time (pre-post photic) and Groups (migraine, TTH, and control group) revealed significant 3-way interactions for measures of PSV (P = 0.012) and MFV (P = 0.043). In the migraine patients there was significantly higher PSV, EDV, and MFV in the MCA, ACA, and PCA after photic stimulation compared with baseline. The CVR of the MCA was also significantly higher in migraineurs than controls. In the TTH group, there was significantly higher PSV, EDV, and MFV (P = 0.003, 0.012, 0.002 respectively) in the VA after photic stimulation than at baseline. The CVR was significantly higher in the VA of TTH patients than controls. CONCLUSION: Compared with controls after photic stimulation, the higher CVR of the MCA in migraineurs and of the VA in TTH patients could be used as diagnostic tool to differentiate between the two types of headaches.


Assuntos
Transtornos de Enxaqueca , Cefaleia do Tipo Tensional , Humanos , Ultrassonografia Doppler Transcraniana/métodos , Cefaleia do Tipo Tensional/diagnóstico por imagem , Estimulação Luminosa , Transtornos de Enxaqueca/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Velocidade do Fluxo Sanguíneo
19.
Sci Rep ; 13(1): 2034, 2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739320

RESUMO

A new electrochemical impedimetric sensor for direct detection of urea was designed and fabricated using nanostructured screen-printed electrodes (SPEs) modified with CuO/Co3O4 @MWCNTs. A facile and simple hydrothermal method was achieved for the chemical synthesis of the CuO/Co3O4 nanocomposite followed by the integration of MWCNTs to be the final platform of the urea sensor. A full physical and chemical characterization for the prepared nanomaterials were performed including Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), contact angle, scanning electron microscope (SEM) and transmission electron microscopy (TEM). Additionally, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties the modified electrodes with the nanomaterials at different composition ratios of the CuO/Co3O4 or MWCNTs. The impedimetric measurements were optimized to reach a picomolar sensitivity and high selectivity for urea detection. From the calibration curve, the linear concentration range of 10-12-10-2 M was obtained with the regression coefficient (R2) of 0.9961 and lower detection limit of 0.223 pM (S/N = 5). The proposed sensor has been used for urea analysis in real samples. Thus, the newly developed non-enzymatic sensor represents a considerable advancement in the field for urea detection, owing to the simplicity, portability, and low cost-sensor fabrication.

20.
Ir J Med Sci ; 192(2): 915-918, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35412213

RESUMO

BACKGROUND : Since the pandemic of SARS-CoV-2 began, our understanding of the pathogenesis and immune responses to this virus has continued to evolve. It has been shown that this infection produces natural detectable immune responses in many cases. However, the duration and durability of immunity and its effect on the severity of the illness are still under investigation. Moreover, the protective effects of antibodies against new SARS-CoV-2 variants still remain unclear. OBJECTIVES: To assess the incidence and associated demographic features of SARS-CoV-2 infection in anti-nucleocapsid IgG-positive and anti-nucleocapsid IgG-negative healthcare workers. MATERIAL AND METHODS: This prospective longitudinal cohort study was conducted in Peshawar Medical College group of hospitals of Prime Foundation. Anti-nucleocapsid IgG sero-positive and anti-nucleocapsid IgG sero-negative healthcare workers were followed for a period of 6 months (from 1 Aug 2020 to 31 Jan 2021), and the incidence of SARS-CoV-2 was confirmed by RT-PCR. RESULTS: A total number of 555 cohorts were followed for a period of 6 months; of them 365 (65.7%) were anti-nucleocapsid-negative (group A) and 190 (34.3%) were anti-nucleocapsid-positive (group B) healthcare workers. The mean age of the study cohort was 33.85 ± 9.80 (anti-N (-), 34.2 ± 10.58; anti-N ( +), 33.5 ± 9.50). The median antibody level in anti-nucleocapsid-positive HCWs was 15.95 (IQR: 5.24-53.4). Male gender was the majority in both groups (group A, 246 (67%), group B, 143 (48%)) with statistically significant difference (P < 0.05). Majority of the HCWs were blood group B in both groups (34% each). None of the 190 anti-nucleocapsid-positive HCWs developed subsequent SARS-CoV-2 re-infection, while 17% (n = 65) HCWs developed infection in anti-nucleocapsid-negative group during the 6-month follow-up period. CONCLUSION: In conclusion, none of the anti-nucleocapsid-positive HCWs developed SARS-CoV-2 re-infection in this study, and the presence of IgG anti-nucleocapsid antibodies substantially reduce the risk of re-infection for a period of 6 months.


Assuntos
COVID-19 , SARS-CoV-2 , Masculino , Humanos , Estudos Prospectivos , COVID-19/epidemiologia , Incidência , Estudos Longitudinais , Reinfecção , Pessoal de Saúde , Imunoglobulina G , Anticorpos Antivirais
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