Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 276
Filtrar
1.
Curr Rheumatol Rev ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693734

RESUMO

OBJECTIVE: To provide evidence-based clinical practice recommendations for managing Systemic Lupus Erythematosus (SLE) in Saudi Arabia. METHODS: This EULAR-adapted national guideline in which a multidisciplinary task force utilized the modified Delphi method to develop 31 clinical key questions. A systematic literature review was conducted to update the evidence since the EULAR publication. After reaching a consensus agreement, two rounds of voting and group discussion were conducted to generate consolidated recommendations/statements. RESULTS: A significant number of patients in Saudi Arabia experience delays in accessing rheumatologists, highlighting the significance of timely referral to SLE specialists or rheumatologists to ensure accurate diagnosis and prompt treatment. The primary goal of Glucocorticoid (GC) therapy in SLE patients is to establish disease control with a minimum dose and duration. Steroid-sparing agent utilization facilitates steroid-sparing goals. Hydroxychloroquine is recommended for all SLE patients, though physicians must carefully monitor toxicity and prioritize regular medication adherence assessment. SLE management during pregnancy starts from preconception time by assessing disease activity, major organ involvement, hypercoagulability status, and concomitant diseases that may negatively impact maternal and fetal outcomes. Multidisciplinary care with close monitoring may optimize both maternal and fetal outcomes. For patients with antiphospholipid antibodies, low-dose aspirin prophylaxis is recommended. Also, Long-term anticoagulant medications are fundamental to prevent secondary antiphospholipid syndrome due to high thrombosis recurrence. CONCLUSION: This Saudi National Clinical Practice guidelines for SLE management provide evidence-based recommendations and guidance for healthcare providers in Saudi Arabia who are managing patients with SLE. These guidelines will help to standardize healthcare service, improve provider education, and perhaps lead to better treatment outcomes for SLE patients.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38699843

RESUMO

BACKGROUND: Calcific mitral stenosis (calcific MS) presents a challenge for surgical treatment and is a contraindication for most contemporary transcatheter mitral valve replacement devices (TMVR), rendering patients with very limited therapeutic options. AIMS: This study aims to assess the clinical and hemodynamic follow-up after mitral valve lithotripsy (MVL). METHODS: All consecutive patients who underwent MVL to treat symptomatic calcific MS at St Michael's Hospital, Toronto, Canada, were included. Patients were deemed unsuitable for mitral surgery or TMVR after heart team assessment. Patients with rheumatic MS or ≥moderate mitral regurgitation (MR) were excluded. The primary endpoint was a reduction in the invasive mitral gradient by ≥50% without significant (≥moderate) MR. RESULTS: Fifteen patients underwent MVL between 2021 and 2023 with a mean age of 74 ± 9 years; 53% were female, with a mean STS score of 10% ± 0.1%. Following MVL, there was a reduction in the invasively measured mean trans-mitral gradient compared to baseline (14 mmHg vs. 6 mmHg; p < 0.05). The primary endpoint was achieved in 8 patients (53%) with no major procedural complications. At follow-up (median 90 days, IQR 58-115 days), 14 (93%) patients reported improved symptoms from New York Heart Association (NYHA) Class III-IV to NYHA Class I-II (p < 0.01) with stable echo-derived mean gradient (7.7 mmHg ± 2 mmHg vs. 8.4 mmHg ± 2.9 mmHg (p = 0.7). CONCLUSIONS: In selected patients with symptomatic inoperable calcific MS, MVL was safe and associated with significant short-term clinical and hemodynamic improvement. MVL may represent a new compassionate therapy for this challenging cohort. Further studies are needed to determine the long-term outcomes and help define the role of IVL technology in treating calcific valvular conditions.

3.
J Neurosurg ; : 1-9, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728760

RESUMO

OBJECTIVE: The most common method for external ventricular drain (EVD) placement is the freehand approach, which has reported inaccuracy rates of 12.3%-44.9%, especially in the case of altered ventricular anatomy. Current assistive devices require added time or equipment or do not account for shifted ventricles. To improve the accuracy of emergent EVD placement in the setting of altered ventricular anatomy, the authors designed a patient-specific EVD (PS-EVD) guide. METHODS: The PS-EVD guide has a tripod base and a series of differently angled inserts that lock in place at multiple rotational positions, allowing for numerous insertion angles. For testing, the authors designed a 3D-printed phantom skull with a gelatin brain analog containing ventricles simulating normal and altered ventricular anatomy. Low-resolution CT scans of the phantom were used to calculate the insertion angle in relation to the standard perpendicular entry. The corresponding insert at the correct rotational position within the base unit was positioned over the entry point on the phantom, and the catheter was inserted. Accuracy was evaluated with repeat CT scans. RESULTS: With normal ventricular anatomy, as well as abnormally shifted ventricles, proper use of the PS-EVD guide led to accurate catheter insertion into the ventricle in trials, as confirmed on coronal and sagittal CT images, including cases in which a perpendicular trajectory, such as with the Ghajar guide, was insufficient. CONCLUSIONS: The PS-EVD guide allows consistent and accurate EVD placement in phantom skulls with both normal and altered ventricular anatomy. Further trials comparing this device to the freehand approach are required.

4.
Sci Rep ; 14(1): 8721, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622184

RESUMO

The applications of terahertz metamaterials are being actively explored in recent times for applications in high-speed communication devices, miniature photonic circuits, and bio-chemical devices because of their wide advantages. The toroidal resonance, a new type of metasurface resonance, has been examined with great interest to utilize its properties in terahertz metasurface applications. This study reports a proof of concept design of a toroidal metasurface that experimentally demonstrates binary computing operations in the terahertz frequency regime. The analog computing of binary operations is achieved by the passive tuning of distance between the split ring resonators comprising the meta-molecule. The amplitude modulation is utilized as a method of determining the Boolean logic outputs of the system. The proposed metasurface could be further optimized for high amplitude modulations and active logic gate operations using tunable materials including graphene and ITO. The proposed metasurface consists of three split-ring resonators, and the near-field coupling between the adjacent resonators dictates the Boolean operations. A multipole analysis of the scattered powers of terahertz radiation determines the toroidal excitation in the metasurface. The proposed metasurfaces experimentally define AND Boolean logic operation at 0.89 terahertz, and OR Boolean logic operation at 0.97 terahertz. Numerical simulations support the experimentally obtained results. Additionally, we numerically report the excitation of NAND operation at 0.87 THz. Such toroidal analog computing metasurfaces could find applications in digitized terahertz circuits and integrated photonic devices.

5.
Cureus ; 16(3): e56725, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38646214

RESUMO

BACKGROUND: As the surgical burden grows, increasing patient safety during anesthesia and surgery becomes a major global public health priority. Anesthesia can be safely administered in higher-income countries, yet it is more challenging in third-world countries. This study focuses on Sudan, a third-world country, and its unmet anesthetic needs before the current war and how these needs might compromise the post-war status. AIM: The aim of this study is to compare Sudan's outstanding anesthesia requirements to the World Health Organization's safe anesthesia practice standards in terms of workforce, medications, equipment, and anesthesia conduct. METHODS: This study was carried out in four hospitals (Wad Medani Teaching Hospital, Wad Medani Maternity Hospital, Gezira Centre for Renal and Urological Surgeries, and the National Centre for Pediatric Surgeries) in Wad Medani, two of which were referral and two were state-run. Each hospital from every category was identified using a convenience sampling technique. The World Health Organization-World Federation of Societies of Anesthesiologists International Standard and earlier regional African publications were used to determine the minimum predicted safe anesthesia needs. RESULTS: The results of our study demonstrate that overall, the hospitals surveyed fulfilled the minimum standards set by the World Health Organization and the World Federation of Societies of Anesthesiologists (WHO-WFSA) for safe anesthesia practice by 73% with no significant difference in the safety of anesthesia practice between state and referral hospitals. CONCLUSIONS: The state of safe anesthesia care in Wad Medani hospitals surveyed fell well short of the expected minimal criteria due to important requirements such as patient monitoring indicators, the inaccessibility of life-saving facilities such as defibrillators, and difficult intubation instruments. More importantly, the conduct of anesthesia was far below the standard.

6.
Pestic Biochem Physiol ; 201: 105855, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685235

RESUMO

Biomphalaria spp. snails are freshwater gastropods that responsible for Schistosoma mansoni transmission. Schistosomiasis is a chronic illness that occurred in underdeveloped regions with poor sanitation. The aim of the present study is to evaluate the molluscicidal activity of benzylamine against B. alexandrina snails and it larvicidal effects on the free larval stages of S. mansoni. Results showed that benzylamine has molluscicidal activity against adult B. alexandrina snails after 24 h of exposure with median lethal concentration (LC50) 85.7 mg/L. The present results indicated the exposure of B. alexandrina snails to LC10 or LC25 of benzylamine resulted in significant decreases in the survival, fecundity (eggs/snail/week) and reproductive rates, acetylcholinesterase, albumin, protein, uric acid and creatinine concentrations, levels of Testosterone (T) and 17ß Estradiol (E), while alkaline phosphatase levels were significantly increased in comparison with control ones. The present results showed that the sub lethal concentration LC50 (85.7 mg/L) of benzylamine has miracidial and cercaricidal activities, where the Lethal Time (LT50) for miracidiae was 17.08 min while for cercariae was 30.6 min. Also, results showed that were decreased significantly after exposure to sub lethal concentrations compared with control. The present results showed that the expression level of NADH dehydrogenase subunit 1 (ND1) genes and cytochrome oxidase subunit I (COI) in B. alexandrina snails exposed to LC10 or LC25 concentrations benzylamine were significantly decreased compared to the control groups. Therefore, benzylamine could be used as effective molluscicide to control schistosomiasis.


Assuntos
Biomphalaria , Larva , Schistosoma mansoni , Animais , Biomphalaria/efeitos dos fármacos , Schistosoma mansoni/efeitos dos fármacos , Larva/efeitos dos fármacos , Moluscocidas/farmacologia
7.
Heart Rhythm ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588996

RESUMO

BACKGROUND: The 2014 Heart Rhythm Society consensus statement defines histological (definite) and clinical (probable) diagnostic categories of cardiac sarcoidosis (CS), but few studies have compared their arrhythmic phenotypes and outcomes. OBJECTIVE: The purpose of this study was to evaluate the electrophysiological/arrhythmic phenotype and outcomes of patients with definite and probable CS. METHODS: We analyzed the arrhythmic/electrophysiological phenotype in a single-center North American cohort of 388 patients (median age 56 years; 39% female, n = 151) diagnosed with definite (n = 58) or probable (n = 330) CS (2000-2022). The primary composite outcome was survival to first ventricular tachycardia/fibrillation (VT/VF) event or sudden cardiac death. Key secondary outcomes were also assessed. RESULTS: At index evaluation, in situ cardiac implantable electronic devices and antiarrhythmic drug use were more common in definite CS. At a median follow-up of 3.1 years, the primary outcome occurred in 22 patients with definite CS (38%) and 127 patients with probable CS (38%) (log-rank, P = .55). In multivariable analysis, only a higher ratio of the 18F-fluorodeoxyglucose maximum standardized uptake value of the myocardium to the maximum standardized uptake value of the blood pool (hazard ratio 1.09; 95% confidence interval 1.03-1.15; P = .003, per 1 unit increase) was associated with the primary outcome. During follow-up, patients with definite CS had a higher burden of device-treated VT/VF events (mean 2.86 events per patient-year vs 1.56 events per patient-year) and a higher rate of progression to heart transplant/left ventricular assist device implantation but no difference in all-cause mortality compared with patients with probable CS. CONCLUSION: Patients with definite and probable CS had similarly high risks of first sustained VT/VF/sudden cardiac death and all-cause mortality, though patients with definite CS had a higher overall arrhythmia burden. Both CS diagnostic groups as defined by the 2014 Heart Rhythm Society criteria require an aggressive approach to prevent arrhythmic complications.

9.
Pathol Res Pract ; 256: 155225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442448

RESUMO

Diabetic cardiomyopathy, a multifaceted complication of diabetes mellitus, remains a major challenge in clinical management due to its intricate pathophysiology. Emerging evidence underscores the pivotal role of autophagy dysregulation in the progression of diabetic cardiomyopathy, providing a novel avenue for therapeutic intervention. Noncoding RNAs (ncRNAs), a diverse class of regulatory molecules, have recently emerged as promising candidates for targeted therapeutic strategies. The exploration of various classes of ncRNAs, including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) reveal their intricate regulatory networks in modulating autophagy and influencing the pathophysiological processes associated with diabetic cardiomyopathy. The nuanced understanding of the molecular mechanisms underlying ncRNA-mediated autophagic regulation offers a rationale for the development of precise and effective therapeutic interventions. Harnessing the regulatory potential of ncRNAs presents a promising frontier for the development of targeted and personalized therapeutic strategies, aiming to ameliorate the burden of diabetic cardiomyopathy in affected individuals. As research in this field advances, the identification and validation of specific ncRNA targets hold immense potential for the translation of these findings into clinically viable interventions, ultimately improving outcomes for patients with diabetic cardiomyopathy. This review encapsulates the current understanding of the intricate interplay between autophagy and diabetic cardiomyopathy, with a focus on the potential of ncRNAs as therapeutic targets.


Assuntos
Diabetes Mellitus , Cardiomiopatias Diabéticas , MicroRNAs , RNA Longo não Codificante , Humanos , Cardiomiopatias Diabéticas/genética , RNA não Traduzido/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Autofagia/genética
10.
Malar J ; 23(1): 80, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491492

RESUMO

BACKGROUND: Malaria vector control activities in Sudan rely largely on Long-Lasting Insecticidal Nets (LLINs), Indoor Residual Spray (IRS) and Larval Source Management (LSM). The present study attempted to determine cost effectiveness of inputs and operations of vector control interventions applied in different environmental settings in central and eastern Sudan, as well as their impact. METHODS: The inputs utilized and cost of each vector control activity, operational achievements and impact of the applied malaria vector control activities; IRS, LLINs and LSM were determined for eight sites in Al Gazira state (central Sudan) and Al Gadarif state (eastern Sudan). Operational costs were obtained from data of the National Malaria Control Program in 2017. Impact was measured using entomological indicators for Anopheles mosquitoes. RESULTS: The total cost per person per year was $1.6, $0.85, and $0.32 for IRS, LLINs and LSM, respectively. Coverage of vector control operations was 97%, 95.2% and 25-50% in IRS, LLINs and LSM, respectively. Vectorial capacity of malaria vectors showed statistically significant variations (P < 0.034) and ranged 0.294-0.65 in areas implemented LSM in comparison to 0.097-0.248 in areas applied IRS and LLINs, respectively. Both indoor and outdoor biting Anopheles mosquitoes showed noticeable increase that reached 3-12 folds in areas implemented LSM in comparison to areas implemented IRS and LLINs. Annual malaria prevalence was 13.1-21.1% in areas implemented LSM in comparison to 3.20%, 4.77% in areas implemented IRS and LLINs, respectively. CONCLUSION: IRS and LLINs are cost effective control measures due to adequate inputs and organized process. However, the unit cost of LSM intervention per outcome and subsequently the impact is hugely affected by the low coverage. The very weak support for implementation of LSM which includes inputs resulted in weakness of its process and consequently its impact. Implementation of LSM by local government in urban settings is challenged by many factors the most important are maintenance of adequate stable level of funding, un-adequate number of well trained health workers, unstable political and administrative conditions and weak infrastructure. These challenges are critical for proper implementation of LSM and control of malaria in urban settings in Sudan.


Assuntos
Anopheles , Mosquiteiros Tratados com Inseticida , Inseticidas , Malária , Animais , Humanos , Controle de Mosquitos/métodos , Análise de Custo-Efetividade , Sudão/epidemiologia , Mosquitos Vetores , Malária/epidemiologia , Malária/prevenção & controle , Inseticidas/farmacologia , Larva
11.
Sultan Qaboos Univ Med J ; 24(1): 103-108, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38434470

RESUMO

Objectives: This study aimed to compare the high-flow nasal oxygen (HFNO) and supraglottic airway device (SAD) techniques in oncological patients undergoing endobronchial ultrasound (EBUS) and transbronchial needle aspiration (TBNA) to evaluate the efficacy of HFNO in them. Methods: This pilot study was conducted at Sultan Qaboos Comprehensive Cancer Care and Research Centre, Muscat, Oman, from May 2022 to March 2023. Patients undergoing EBUS TBNA under moderate sedation were quasi-randomised into the HFNO and SAD groups. The episodes and duration of hypoxia and the lowest level of oxygen saturation were the primary outcomes measured. Results: A total of 24 patients were included in the study (10 of them were in the HFNO group and 14 were in the SAD group), with an equal number of males and females. The duration of the procedure in both groups was similar (45 ± 20 and 44 ± 17 minutes in the HFNO and SAD groups, respectively). The mean lowest oxygen saturation in the HFNO group was 93.5 ± 4.5%, which was significantly higher than that of the SAD group (90 ± 3%; P <0.001). In both groups, maximum hypoxia occurred during the early phase of the procedure. However, the HFNO and SAD groups were similar in terms of the cumulative duration of hypotension (140 versus 95 seconds, respectively) and bradycardia (25 versus 40 seconds, respectively). Conclusion: HFNO is a good alternative to SAD and could be used safely and efficiently in patients undergoing EBUS TBNA.


Assuntos
Hipóxia , Ultrassonografia de Intervenção , Feminino , Masculino , Humanos , Projetos Piloto , Biópsia por Agulha Fina , Omã
12.
Bioanalysis ; 16(7): 149-163, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38385904

RESUMO

Aims: AZD7442 is a combination SARS-CoV-2 therapy comprising two co-dosed monoclonal antibodies. Materials & methods: The authors validated a hybrid ligand-binding assay-LC-MS/MS method for pharmacokinetic assessment of AZD7442 in human serum with nominal concentration range of each analyte of 0.300-30.0 µg/ml. Results: Validation results met current regulatory acceptance criteria. The validated method supported three clinical trials that spanned more than 17 months and ≥720 analytical runs (∼30,000 samples and ∼3000 incurred sample reanalyses per analyte). The data generated supported multiple health authority interactions, across the globe. AZD7442 (EVUSHELD) was approved in 12 countries for pre-exposure prophylaxis of COVID-19. Conclusion: The results reported here demonstrate the robust, high-throughput capability of the hybrid ligand-binding assay-LC-MS/MS approach being employed to support-next generation versions of EVUSHELD, AZD3152.


The measurement of antibodies in human body fluids (e.g., blood, serum) has historically been tied to laboratory tests that may face operational limitations, including susceptibility to interference from other blood components and a reliance on unique reagents that can take months to produce. As such, there is a pursuit of alternative analytical methods to more accurately detect and measure antibody drugs from complex matrices. In the method, the authors describe different techniques that once combined were used to capture, separate, filter, fragment and then detect and measure the co-dosed antibody drugs. This method has been validated in accordance with current health authority guidelines and has been used to support three clinical trials that spanned more than 17 months; that is, the validated method was used to analyze nearly 30,000 serum samples from more than 2000 patients. Collectively, the results reported here demonstrate the robustness and high-throughput capability of this analytical approach.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Espectrometria de Massa com Cromatografia Líquida , Humanos , Cromatografia Líquida/métodos , Ligantes , Espectrometria de Massas em Tandem/métodos , SARS-CoV-2 , Anticorpos Monoclonais/uso terapêutico , Combinação de Medicamentos
13.
Cureus ; 16(1): e51929, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38333483

RESUMO

Background The immune system, composed of various molecules and cells, protects humans from cancer and pathogens. A breach of tolerance, known as autoimmune disease (AD), is the root of these diseases. Systemic lupus erythematosus (SLE) is an autoimmune condition characterized by chronic inflammation, causing tissue damage in various organ systems. The disease is influenced by hormonal, environmental, and genetic factors. The pathophysiology is unclear, and 20% to 30% of patients have a persistent illness. SLE affects young females more than males, and treatments focus on organ manifestations. Despite advancements and better diagnoses, SLE continues to contribute significantly to morbidity and early mortality. Objective This study aims to assess knowledge of SLE among the general population of Jeddah, Saudi Arabia. Methodology An online cross-sectional survey using Google Forms was conducted for Jeddah residents aged 18 and above. The survey was open for responses from August 2023 to October 2023. Results The study included 479 participants, with 19 (25%) males and 57 (75%) females diagnosed with SLE. The majority of these individuals were housewives and unemployed. The majority were married (46, 60.5%), with only 25 (32.9%) being single. Among healthy participants, there were 173 (42.9%) males and 230 (57.1%) females, with a majority being housewives and government employees (95, 23.6%). Singles accounted for 124 (30.8%), while married individuals constituted 253 (62.8%). Among the healthy population respondents, 254 (63%) lacked knowledge about SLE treatment, while 40 (52.6%) SLE patients believed that a combination of chemotherapy, malaria medication, and steroids was the best treatment. The study found that 393 (82%) of the sample had heard about SLE, and 250 (52%) believed it was not a contagious disease. More than 30 were unaware of SLE. The majority of the respondents felt they needed more awareness and health promotion about SLE, with 410 (85.77%) stating they needed more promotion. The majority of the people believed SLE was dangerous to some extent. Conclusions This study revealed the need and necessity of awareness of SLE among the general community of Jeddah. We advocate undertaking disease awareness programs and activities to increase general community knowledge and awareness of SLE in the city of Jeddah.

14.
PLoS One ; 19(2): e0298431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38319931

RESUMO

Intermetallic alloy containing rare earth dysprosium ions with the associated unfilled 4f shell electrons and sub-lattice of 3d-transition metal, results into fascinating magnetic properties which are useful for green refrigeration technological application. Magnetocaloric effect remains the fundamental principle upon which magnetic refrigeration technology is based while this cooling technology has advantages of cost effectiveness, high efficiency and environmental friendliness as compared with the existing conventional gas compression systems. Maximum magnetic entropy change (which controls the hugeness of magnetocaloric effect) of intermetallic alloy Dy-T-X (where T = transition metal and X = any other metal or nonmetal) is modeled in this work using hybrid genetic algorithm based support vector regression (GSVR) computational intelligent method with applied magnetic field, ionic concentration and ionic radii descriptors. The developed GSVR-G model with kernel Gaussian function outperforms GSVR-P model with polynomial function with improvement of 85.23%, 78.82% and 78.67% on the basis of the computed correlation coefficient (CC), mean absolute error (MAE) and root mean square error (RMSE) on testing sample, respectively. The developed model further investigates the influence of applied external magnetic field on magnetocaloric effect of DyCuAl intermetallic alloy. The developed models in this work circumvent experimental challenges of magnetocaloric effect determination while the recorded precision of the developed model further opens doors for possible exploration of these intermetallic compounds for addressing environmental challenges associated with the present system of cooling.


Assuntos
Ligas , Disprósio , Refrigeração , Fenômenos Físicos , Elétrons
15.
ACS Mater Au ; 4(1): 74-81, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38221925

RESUMO

Transition metal oxides are characterized by an acute structure and composition dependent electrocatalytic activity toward the oxygen evolution (OER) and oxygen reduction (ORR) reactions. For instance, Mn containing oxides are among the most active ORR catalysts, while Ni based compounds tend to show high activity toward the OER in alkaline solutions. In this study, we show that incorporation of Ni into α-MnO2, by adding Ni precursor into the Mn-containing hydrothermal solution, can generate distinctive sites with different electronic configurations and contrasting electrocatalytic activity. The structure and composition of the Ni modified hollandite α-MnO2 phase were investigated by X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), transmission electron microscopy coupled to energy-dispersive X-ray spectroscopy (TEM-EDX), inductively coupled plasma-optical emission spectroscopy (ICP-OES), and X-ray photoelectron spectroscopy (XPS). Our analysis suggests that Mn replacement by Ni into the α-MnO2 lattice (site A) occurs up to approximately 5% of the total Mn content, while further increasing Ni content promotes the nucleation of separate Ni phases (site B). XAS and XRD show that the introduction of sites A and B have a negligible effect on the overall Mn oxidation state and bonding characteristics, while very subtle changes in the XPS spectra appear to suggest changes in the electronic configuration upon Ni incorporation into the α-MnO2 lattice. On the other hand, changes in the electronic structure promoted by site A have a significant impact in the pseudocapacitive responses obtained by cyclic voltammetry in KOH solution at pH 13, revealing the appearance of Mn 3d orbitals at the energy (potential) range relevant to the ORR. The evolution of Mn 3d upon Ni replacement significantly increases the catalytic activity of α-MnO2 toward the ORR. Interestingly, the formation of segregated Ni phases (site B) leads to a decrease in the ORR activity while increasing the OER rate.

16.
Food Chem ; 442: 138435, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266415

RESUMO

A new analytical method for measuring copper in food and water was developed and validated, employing a solid-phase extraction (SPE) technique combined with digital-image-based (DIB) detection. A novel magnetic adsorbent of zinc ferrite/Citrullus colocynthis biochar (ZF@C.BC) was used to preconcentrate copper. A magnetic tip was used to separate the copper-loaded adsorbent from the extraction medium and to dispense it to the DIB plate. In-situ desorption and development of the spot color with iodide-starch reagent were carried out, and a digital image of the developed spots was captured using a smartphone and processed using ImageJ software. The copper adsorption capacity was 91.3 mg g-1. Desorption was effected using a 0.3 mol L-1 hydrochloric acid. The preconcentration factor was 300, the limit of detection was 4.8 µg L-1, the linearity was 16-600 µg L-1 and the sample throughput was 12 h-1. The developed approach was validated by analyzing food and water samples, confirming recoveries ≥ 91 % and 88 %, respectively, with RSD ≤ 8.4 %, n = 3.


Assuntos
Cobre , Água , Adsorção , Alimentos , Extração em Fase Sólida/métodos , Fenômenos Magnéticos
17.
Evol Appl ; 17(1): e13636, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38283598

RESUMO

Urbanization and its urban-heat-island effect (UHI) have expanding footprints worldwide. The UHI means that urban habitats experience a higher mean and more frequent extreme high temperatures than rural habitats, impacting the ontogeny and resilience of urban biodiversity. However, many organisms occupy different microhabitats during different life stages and thus may experience the UHI differently across their development. While evolutionary changes in heat tolerance in line with the UHI have been demonstrated, it is unknown whether such evolutionary responses can vary across development. Here, using common-garden-reared Chiasmia clathrata moths from urban and rural populations from three European countries, we tested for urban evolution of heat shock tolerance in two life stages: larvae and adults. Our results indicate widespread urban evolution of increased heat tolerance in the adult stage only, suggesting that the UHI may be a stronger selective agent in adults. We also found that the difference in heat tolerance between urban and rural populations was similar to the difference between Mid- and North-European regions, suggesting similarity between adaptation to the UHI and natural, latitudinal temperature variation. Our observations incentivize further research to quantify the impact of these UHI adaptations on fitness during urbanization and climate change, and to check whether life-stage-specific adaptations in heat tolerance are typical of other ectothermic species that manage to survive in urbanized settings.

18.
Obes Surg ; 34(3): 874-881, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38285303

RESUMO

BACKGROUND: Despite the well-described optimal initial clinical response of sleeve gastrectomy (SG) in the treatment of obesity, some patients do not achieve optimal initial clinical response. Insulin-like growth factor-1 (IGF-1) has currently shown an association with post-bariatric surgery weight loss. This study aimed to assess the IGF-1 levels in female patients with obesity, the change after surgery, and their association with the metabolic profile and weight loss after surgery. PATIENTS AND METHODS: This was a prospective study that was conducted on adult female patients who were recruited for SG. The patients underwent clinical and laboratory investigations that included the IGF-1 measurement. At the 1-year follow-up, the same clinical and laboratory measures were repeated. RESULTS: This study included 100 female patients. At the 1-year follow-up, there was a statistically significant reduction in body mass index (BMI) (p < 0.001), fasting HbA1C levels (p < 0.001), and triglycerides (p < 0.001), as well as a statistically significant increase in HDL (p < 0.001) and IGF-1 (p < 0.001). Multiple regression analysis revealed that, among the patients baseline characteristics, the significant predictors for the percentage of total weight loss (%TWL) were the patients' BMI (p < 0.001) and IGF-1 levels (p < 0.001). The ROC curve showed that an IGF1 cutoff value of ≤ 23 ng/ml detected suboptimal initial clinical response, with a sensitivity of 95.35% and a specificity of 100%. CONCLUSION: This study underscores the significant impact of SG on weight loss and metabolic improvements in female patients. Baseline IGF-1 levels emerged as a crucial predictor of optimal initial clinical response.


Assuntos
Laparoscopia , Obesidade Mórbida , Adulto , Humanos , Feminino , Obesidade Mórbida/cirurgia , Peptídeos Semelhantes à Insulina , Fator de Crescimento Insulin-Like I , Estudos Prospectivos , Obesidade/cirurgia , Gastrectomia , Redução de Peso , Resultado do Tratamento , Índice de Massa Corporal , Estudos Retrospectivos
19.
Environ Geochem Health ; 46(2): 38, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227164

RESUMO

The seasonal variation of petroleum pollution including n-alkanes in surface sediments of the Selangor River in Malaysia during all four climatic seasons was investigated using GC-MS. The concentrations of n-alkanes in the sediment samples did not significantly correlate with TOC (r = 0.34, p > 0.05). The concentrations of the 29 n-alkanes in the Selangor River ranged from 967 to 3711 µg g-1 dw, with higher concentrations detected during the dry season. The overall mean per cent of grain-sized particles in the Selangor River was 85.9 ± 2.85% sand, 13.5 ± 2.8% clay, and 0.59 ± 0.34% gravel, respectively. n-alkanes are derived from a variety of sources, including fresh oil, terrestrial plants, and heavy/degraded oil in estuaries. The results of this study highlight concerns and serve as a warning that hydrocarbon contamination is affecting human health. As a result, constant monitoring and assessment of aliphatic hydrocarbons in coastal and riverine environments are needed.


Assuntos
Hidrocarbonetos , Rios , Humanos , Estações do Ano , Malásia , Alcanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...