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1.
Heliyon ; 10(7): e27526, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586377

RESUMEN

Mercury is a toxic pollutant that poses risks to both human and environmental health, making it a pressing public health concern. This study aimed to summarize the knowledge on mercury toxicology and the biological impairments caused by exposure to mercury in experimental studies and/or diagnosis in humans. The research was conducted on the main collection of Web of Science, employing as a methodological tool a bibliometric analysis. The selected articles were analyzed, and extracted data such as publication year, journal, author, title, number of citations, corresponding author's country, keywords, and the knowledge mapping was performed about the type of study, chemical form of mercury, exposure period, origin of exposure, tissue/fluid of exposure measurement, mercury concentration, evaluation period (age), mercury effect, model experiments, dose, exposure pathway, and time of exposure. The selected articles were published between 1965 and 2021, with Clarkson TW being the most cited author who has also published the most articles. A total of 38% of the publications were from the USA. These studies assessed the prenatal and postnatal effects of mercury, emphasizing the impact of methylmercury on neurodevelopment, including motor and cognitive evaluations, the association between mercury and autism, and an evaluation of its protective effects against mercury toxicity. In observational studies, the blood, umbilical cord, and hair were the most frequently used for measuring mercury levels. Our data analysis reveals that mercury neurotoxicology has been extensively explored, but the association among the outcomes evaluated in experimental studies has yet to be strengthened. Providing metric evidence on what is unexplored allows for new studies that may help governmental and non-governmental organizations develop guidelines and policies.

2.
Materials (Basel) ; 17(3)2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38591454

RESUMEN

Premature failure and degradation of layers are the main problems for transportation infrastructure. Addressing these issues necessitates implementing structural health monitoring (SHM) for pavement construction layers. To this end, this research investigated the stress/strain and damage detection capabilities of a self-sensing cementitious composite developed for potential utilization in the construction of an intelligent subgrade layer. The prepared self-sensing cementitious composite consisted of 10% cement and hybrid conductive fillers, including multiwalled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs) in sand. Initial findings reveal that the electrical resistivity of the composite is significantly affected by the concentration of MWCNTs/GNPs, with a minimum concentration of more than 0.5% needed to achieve a responsive cementitious composite. Moreover, the piezoresistive analysis indicates that an increase in the concentration of MWCNTs/GNPs and stress levels leads to an improvement in the stress/strain-sensing performance. When the self-sensing cementitious composite is subjected to equivalent stress levels, variations in the fractional changes in resistivity (FCR) exhibit an increasing trend with decreasing resilient modulus, stemming from a decrease in stiffness due to the increased concentration of MWCNTs/GNPs. Additionally, the electrochemical impedance spectroscopy (EIS) analysis demonstrates a contraction for the Nyquist plots under compressive ramp loading prior to failure, followed by the expansion of these curves post-failure. Scanning electron microscopy (SEM) images visually showcase the bridging effects of MWCNTs and the filling effects of GNPs within the composite structure.

3.
Inorg Chem ; 63(13): 5783-5804, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38502532

RESUMEN

In recent years, organometallic complexes have attracted much attention as anticancer therapeutics aiming at overcoming the limitations of platinum drugs that are currently marketed. Still, the development of half-sandwich organometallic cobalt complexes remains scarcely explored. Four new cobalt(III)-cyclopentadienyl complexes containing N,N-heteroaromatic bidentate, and phosphane ligands were synthesized and fully characterized by elemental analysis, spectroscopic techniques, and DFT methods. The cytotoxicity of all complexes was determined in vitro by the MTS assay in colorectal (HCT116), ovarian (A2780), and breast (MDA-MB-231 and MCF-7) human cancer cell lines and in a healthy human cell line (fibroblasts). The complexes showed high cytotoxicity in cancer cell lines, mostly due to ROS production, apoptosis, autophagy induction, and disruption of the mitochondrial membrane. Also, these complexes were shown to be nontoxic in vivo in an ex ovo chick embryo yolk sac membrane (YSM) assay.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias Ováricas , Animales , Embrión de Pollo , Humanos , Femenino , Línea Celular Tumoral , Antineoplásicos/química , Platino (Metal)/farmacología , Cobalto/farmacología , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Apoptosis
4.
BMC Geriatr ; 24(1): 25, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38182982

RESUMEN

BACKGROUND: Although dementia has emerged as an important risk factor for severe SARS-CoV-2 infection, results on COVID-19-related complications and mortality are not consistent. We examined the clinical presentations and outcomes of COVID-19 in a multicentre cohort of in-hospital patients, comparing those with and without dementia. METHODS: This retrospective observational study comprises COVID-19 laboratory-confirmed patients aged ≥ 60 years admitted to 38 hospitals from 19 cities in Brazil. Data were obtained from electronic hospital records. A propensity score analysis was used to match patients with and without dementia (up to 3:1) according to age, sex, comorbidities, year, and hospital of admission. Our primary outcome was in-hospital mortality. We also assessed admission to the intensive care unit (ICU), invasive mechanical ventilation (IMV), kidney replacement therapy (KRT), sepsis, nosocomial infection, and thromboembolic events. RESULTS: Among 1,556 patients included in the study, 405 (4.5%) had a diagnosis of dementia and 1,151 were matched controls. When compared to matched controls, patients with dementia had a lower frequency of dyspnoea, cough, myalgia, headache, ageusia, and anosmia; and higher frequency of fever and delirium. They also had a lower frequency of ICU admission (32.7% vs. 47.1%, p < 0.001) and shorter ICU length of stay (7 vs. 9 days, p < 0.026), and a lower frequency of sepsis (17% vs. 24%, p = 0.005), KRT (6.4% vs. 13%, p < 0.001), and IVM (4.6% vs. 9.8%, p = 0.002). There were no differences in hospital mortality between groups. CONCLUSION: Clinical manifestations of COVID-19 differ between older inpatients with and without dementia. We observed that dementia alone could not explain the higher short-term mortality following severe COVID-19. Therefore, clinicians should consider other risk factors such as acute morbidity severity and baseline frailty when evaluating the prognosis of older adults with dementia hospitalised with COVID-19.


Asunto(s)
COVID-19 , Demencia , Sepsis , Humanos , Anciano , Brasil/epidemiología , Estudios de Cohortes , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/epidemiología , SARS-CoV-2 , Pacientes Internos , Demencia/diagnóstico , Demencia/epidemiología , Demencia/terapia
5.
J Clin Lipidol ; 18(2): e142-e152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38142178

RESUMEN

Atherosclerosis is a chronic inflammatory disease characterized by the buildup of plaques in arterial walls, leading to cardiovascular diseases and high morbidity and mortality rates worldwide. Non-invasive imaging techniques play a crucial role in evaluating patients with suspected or established atherosclerosis. However, there is a growing body of evidence suggesting the need to visualize the underlying processes of plaque progression and rupture to enhance risk stratification. This review explores recent advancements in non-invasive assessment of atherosclerosis, focusing on computed tomography, magnetic resonance imaging, and nuclear imaging. These advancements provide valuable insights into the assessment and management of atherosclerosis, potentially leading to better risk stratification and improved patient outcomes.


Asunto(s)
Aterosclerosis , Imagen por Resonancia Magnética , Humanos , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/diagnóstico , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/patología , Placa Aterosclerótica/diagnóstico , Diagnóstico por Imagen/métodos
6.
OTJR (Thorofare N J) ; 44(1): 148-156, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37586012

RESUMEN

The Occupational Self-Assessment version 2.2 (OSA) is a self-assessment of the client's occupational competence and values. To describe the process of cross-cultural adaptation of OSA into Brazilian Portuguese (OSA-Brazil) and examine its reliability and validity for use with the Brazilian population. Assessment translation was guided by two international guidelines for cross-cultural adaptation of standardized instruments. Face validity was tested with 24 participants. Internal consistency, test-retest reliability, and convergent validity were tested with a convenience sample of 40 participants. The cross-cultural adaptation process concluded with a consensus among the expert panel review (r > 80%) and evidence of strong face validity. The OSA-Brazil demonstrated appropriate test-retest reliability (r > 0.70) and convergent validity with the 36-Item Short-Form Health Survey (SF-36) (p < .05). The OSA-Brazil has good face validity, test-retest reliability, and convergent validity. The assessment can be used by the Brazilian occupational therapists to assess client's occupational competence.


Asunto(s)
Comparación Transcultural , Autoevaluación (Psicología) , Humanos , Encuestas y Cuestionarios , Brasil , Reproducibilidad de los Resultados , Traducciones , Psicometría
7.
Front Physiol ; 14: 1214990, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731541

RESUMEN

This study aimed to investigate if apical periodontitis in different periods changes systemic levels of the antioxidant and pro-oxidant parameters in Wistar rats. Twenty-four rats were randomly allocated into healthy animals, apical periodontitis at 14 days (AP14) and apical periodontitis at 28 days (AP28). The first mandibular molars were accessed in the AP groups, and the pulp chamber was exposed to the oral environment, inducing the apical lesion. After 14 and 28 days, the animals were anesthetized, euthanized, and hemimandibles were collected for micro-computed tomography (micro-CT) analysis to measure lesion volume, bone volume (BV), percent of bone to total tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular space (Tb.Sp). A histological examination of the remaining bone was also performed. Finally, blood samples were collected for oxidative biochemistry analysis, investigating glutathione (GSH), Trolox equivalent antioxidant capacity (TEAC), and lipid peroxidation (TBARS). The lesion volume was greater at 28 than at 14 days, as shown by micro-CT. AP14 and AP28 had decreased BV and Tb.Th, but only AP28 showed a reduction in BV/TV. Tb.N and Tb. Sp were increased in apical periodontitis at 28 days. In the histopathological analysis, AP14 had focal regions of moderate mononuclear inflammatory infiltrate, and AP28 had an intense inflammatory infiltrate with bacterial colonies. In the biochemical evaluation, GSH, TEAC, and TBARS were increased after 14 days. However, GSH returned to control levels, TEAC was similar to AP14, and TBARS increased significantly after 28 days. Therefore, the oxidative biochemistry response was modulated according to the progression of periapical damage. After 14 days, the organism could still react to the injury. However, at 28 days, the antioxidant response decreased, associated with an increase in TBARS.

8.
Front Pharmacol ; 14: 1209616, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37593178

RESUMEN

Alcohol consumption is common in many societies and has increased considerably, resulting in many socioeconomic and public health problems. In this sense, studies have been carried out in order to understand the mechanisms involved in alcohol consumption and related harmful effects. This study aimed to identify and map the knowledge and to perform bibliometric analysis of the neurotoxicology of alcohol based on the 100 most cited articles. A search was carried out in the Web of Science Core Collection database and information was extracted regarding the journal, authors, keywords, year of publication, number of citations, country and continent of the corresponding author. For each selected manuscript, the study design, alcohol exposure model, dose, period of exposure, and effect on the central nervous system and research hotspots were mapped. The journal with the highest number of publications was Alcoholism: Clinical and Experimental Research (n = 11 papers), the author who contributed the most was Crews FT (n = 8 papers), the studies had a total of 288 keywords and 75% of the publications were from the United States of America. The experimental studies evaluated the effects of prenatal and postnatal exposure and were conducted in rats and mice using doses ranging from 2.5 to 14 g/kg/day, with administration by subcutaneous, intraperitoneal, intragastric, or inhalation route or with free access through drinking bottles. Among the studies mapped, the oldest one (1989) aimed to understand the systemic damage and mechanisms of action involved, while the most recent focused on understanding the receptors and mechanisms involved in addiction, as well as genetic factors. Our results show the panorama of the most widespread scientific production in the scientific community on the neurotoxicology of ethanol, a high prevalence was observed in studies that addressed fetal alcohol syndrome and/or the effects of ethanol on neurodevelopment.

9.
ACS Appl Mater Interfaces ; 15(33): 39872-39882, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37527439

RESUMEN

This study explores the potential of integrating thin-film technology in the design of new and effective electromagnetic interference (EMI) shielding and conductive materials for textiles and wearables. This application is of particular interest to the textile industry as it can bring new functionalities to wearables and protect humans from prolonged exposure to EM radiation. Three different thin films of pure Ti, pure Cu, and Ti-doped with Cu prepared by magnetron sputtering were used to functionalize textile knits based on cotton (code 39F) and lyocell fibers (62I). The films displayed different crystalline structures, morphologies, and topographies, which depended on their chemical compositions. The shielding effectiveness (SE) of the functionalized knits against EMI was evaluated in the frequency range of 2-8 GHz. Also, the electrical response under stress was assessed since the electrical conductivity is closely related to the EMI shielding effectiveness. The results demonstrate the feasibility of using a thin conductive layer based on Cu or Ti-Cu to improve the shield textiles with great adhesion and low thickness, providing an interesting path to improve shielding efficiency for EMI without modifying the flexibility of the textiles.

10.
Braz J Infect Dis ; 27(4): 102791, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37500062

RESUMEN

INTRODUCTION: Patients hospitalized with COVID-19 are often submitted to invasive procedures and they are at risk for hospital-associated adverse events. OBJECTIVES: To evaluate the epidemiological and clinical aspects of patients hospitalized with COVID-19; the occurrence of adverse events and the risk factors for mortality. METHOD: Cohort study that included adult patients hospitalized with a diagnosis of SARSCoV-2 infection, at the tertiary University Hospital of UNICAMP from March 2020 to March 2021. Patients were identified through the hospital epidemiological surveillance system and followed until discharge or death. Descriptive, comparative, and logistic regression analysis was performed. RESULTS: 650 adult patients were included. The main adverse events identified were nosocomial infections (31.5%), renal failure (33.8%), thromboembolic and vascular events (12.6%). Mortality was higher among those with bloodstream infections (30.2% vs. 8.6%; p < 0.0001), ventilator-associated pneumonia (VAP, 52.5% vs. 12.3%; p < 0.0001), catheter associated urinary infection (27.3% vs. 7.2%; p < 0.0001); thromboembolic and vascular events (23.0% vs. 9.9%; p < 0.0001) and renal failure (81.3% vs. 20.9%; p < 0.0001). Klebsiella pneumoniae (15.6%), Pseudomonas aeruginosa (14.4%), Enterococcus faecalis (8.6%) were the most isolated bacteria. Logistic regression analysis identified age, (RR = 1.03; 95% CI 1.02 to 1.05); ICU admission (RR = 3.06; 95% CI 1.59 to 5.87), vasoactive drug use (RR = 3.1; 95% CI 1.79 to 4.82); renal failure (RR = 7.76; 95% CI 4.54 to 13.26); and VAP (RR = 2.2; 95% CI 1.23 to 3.96), independently associated with mortality. CONCLUSION: adverse events have an important impact on the evolution of patients with COVID-19, reinforcing the need for optimized prevention and control measures as an essential part of care for these patients.


Asunto(s)
COVID-19 , Insuficiencia Renal , Adulto , Humanos , Estudios de Cohortes , Centros de Atención Terciaria , Brasil/epidemiología , Unidades de Cuidados Intensivos , Mortalidad Hospitalaria
11.
J Int Med Res ; 51(6): 3000605231177187, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37291854

RESUMEN

OBJECTIVE: To investigate characteristics that may be associated with radiologic and functional findings following discharge in patients with severe coronavirus disease 2019 (COVID-19). METHODS: This single-center, prospective, observational cohort study comprised patients aged >18 years who were hospitalized with COVID-19 pneumonia, between May and October 2020. After 3 to 6 months of discharge, patients were clinically evaluated and underwent spirometry, a 6-minute walk test (6MWT), and chest computed tomography (CT). Statistical analysis was performed using association and correlation tests. RESULTS: A total of 134 patients were included (25/114 [22%] were admitted with severe hypoxemia). On the follow-up chest CT, 29/92 (32%) had no abnormalities, regardless of the severity of the initial involvement, and the mean 6MWT distance was 447 m. Patients with desaturation on admission had an increased risk of remaining CT abnormalities: patients with SpO2 between 88 and 92% had a 4.0-fold risk, and those with SpO2 < 88% had a 6.2-fold risk. The group with SpO2 < 88% also walked shorter distances than patients with SpO2 between 88 and 92%. CONCLUSION: Initial hypoxemia was found to be a good predictor of persistent radiological abnormalities in follow-up and was associated with low performance in 6MWT.


Asunto(s)
COVID-19 , Humanos , Estudios Prospectivos , Oximetría , Hipoxia/diagnóstico por imagen , Tomografía Computarizada por Rayos X
12.
Antioxidants (Basel) ; 12(5)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37237917

RESUMEN

Binge drinking is the most frequent consumption pattern among young adults and remarkably changes the central nervous system; thus, research on strategies to protect it is relevant. This study aimed to investigate the detrimental effects of binge-like EtOH intake on the spinal cord of male rats and the potential neuroprotective effects provided by moderate-intensity aerobic physical training. Male Wistar rats were distributed into the 'control group', 'training group', 'EtOH group', and 'training + EtOH'. The physical training protocol consisted of daily 30-min exercise on a treadmill for 5 consecutive days followed by 2 days off during 4 weeks. After the fifth day of each week, distilled water ('control group' and 'training group') or 3 g/kg of EtOH diluted at 20% w/v ('EtOH group' and 'training + EtOH group') was administered for 3 consecutive days through intragastric gavage to simulate compulsive consumption. Spinal cord samples were collected for oxidative biochemistry and morphometric analyses. The binge-like EtOH intake induced oxidative and tissue damage by decreasing reduced glutathione (GSH) levels, increasing lipid peroxidation (LPO), and reducing motor neurons (MN) density in the cervical segment. Even under EtOH exposure, physical training maintained GSH levels, reduced LPO, and prevented MN reduction at the cervical segment. Physical training is a non-pharmacological strategy to neuroprotect the spinal cord against oxidative damage induced by binge-like EtOH intake.

13.
Heliyon ; 9(4): e15130, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37123956

RESUMEN

The relationship between class size and school performance has always been ambiguous and the current literature has found no direct connection between them, especially in the Brazilian context. Therefore, this study aimed to verify whether the number of students per class influences school performance. We used Microdata from the Prova Brazil of 2017. Using the propensity score matching statistical model, with the nearest neighbor matching estimator, we grouped the classes into clusters by similarity. The metric used to group the clusters was the Euclidean distance. We attempted to verify adherence to the normal distribution of data using the Kolmogorov Smirnov test and tested the null hypothesis of the medians using the Wilcoxon test. All the statistical analysis were performed using SPSS Statistic version 20. The results showed that the number of students per class has little influence on performance and, when the influence exists, larger classes perform better.

14.
Arq Bras Cardiol ; 120(2): e20220151, 2023.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-36856237

RESUMEN

BACKGROUND: Cardiovascular complications of COVID-19 are important aspects of the disease's pathogenesis and prognosis. Evidence on the prognostic role of troponin and myocardial injury in Latin American hospitalized COVID-19 patients is still scarce. OBJECTIVES: To evaluate myocardial injury as independent predictor of in-hospital mortality and invasive mechanical ventilation support in hospitalized patients, from the Brazilian COVID-19 Registry. METHODS: This cohort study is a substudy of the Brazilian COVID-19 Registry, conducted in 31 Brazilian hospitals of 17 cities, March-September 2020. Primary outcomes included in-hospital mortality and invasive mechanical ventilation support. Models for the primary outcomes were estimated by Poisson regression with robust variance, with statistical significance of p<0.05. RESULTS: Of 2,925 patients (median age of 60 years [48-71], 57.1% men), 27.3% presented myocardial injury. The proportion of patients with comorbidities was higher among patients with cardiac injury (median 2 [1-2] vs. 1 [0-2]). Patients with myocardial injury had higher median levels of brain natriuretic peptide, lactate dehydrogenase, creatine phosphokinase, N-terminal pro-brain natriuretic peptide, and C-reactive protein than patients without myocardial injury. As independent predictors, C-reactive protein and platelet counts were related to the risk of death, and neutrophils and platelet counts were related to the risk of invasive mechanical ventilation support. Patients with high troponin levels presented a higher risk of death (RR 2.03, 95% CI 1.60-2.58) and invasive mechanical ventilation support (RR 1.87, 95% CI 1.57-2.23), when compared to those with normal troponin levels. CONCLUSION: Cardiac injury was an independent predictor of in-hospital mortality and the need for invasive mechanical ventilation support in hospitalized COVID-19 patients.


FUNDAMENTO: As complicações cardiovasculares da COVID-19 são aspectos importantes da patogênese e do prognóstico da doença. Evidências do papel prognóstico da troponina e da lesão miocárdica em pacientes hospitalizados com COVID-19 na América Latina são ainda escassos. OBJETIVOS: Avaliar a lesão miocárdica como preditor independente de mortalidade hospitalar e suporte ventilatório mecânico em pacientes hospitalizados, do registro brasileiro de COVID-19. MÉTODOS: Este estudo coorte é um subestudo do registro brasileiro de COVID-19, conduzido em 31 hospitais brasileiros de 17 cidades, de março a setembro de 2020. Os desfechos primários incluíram mortalidade hospitalar e suporte ventilatório mecânico invasivo. Os modelos para os desfechos primários foram estimados por regressão de Poisson com variância robusta, com significância estatística de p<0,05. RESULTADOS: Dos 2925 pacientes [idade mediana de 60 anos (48-71), 57,1%], 27,3% apresentaram lesão miocárdica. A proporção de pacientes com comorbidades foi maior nos pacientes com lesão miocárdica [mediana 2 (1-2) vs. 1 (0-20)]. Os pacientes com lesão miocárdica apresentaram maiores valores medianos de peptídeo natriurético cerebral, lactato desidrogenase, creatina fosfoquinase, N-terminal do pró-peptídeo natriurético tipo B e proteína C reativa em comparação a pacientes sem lesão miocárdica. Como fatores independentes, proteína C reativa e contagem de plaquetas foram relacionados com o risco de morte, e neutrófilos e contagem de plaquetas foram relacionados ao risco de suporte ventilatório mecânico invasivo. Os pacientes com níveis elevados de troponina apresentaram um maior risco de morte (RR 2,03, IC95% 1,60-2,58) e suporte ventilatório mecânico (RR 1,87;IC95% 1,57-2,23), em comparação àqueles com níveis de troponina normais. CONCLUSÃO: Lesão cardíaca foi um preditor independente de mortalidade hospitalar e necessidade de suporte ventilatório mecânico em pacientes hospitalizados com COVID-19.


Asunto(s)
COVID-19 , Lesiones Cardíacas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Brasil/epidemiología , Proteína C-Reactiva , Estudios de Cohortes , Pronóstico , Anciano
15.
Nat Commun ; 14(1): 819, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36781851

RESUMEN

Metal promotion is the most widely adopted strategy for enhancing the hydrogenation functionality of an oxide catalyst. Typically, metal nanoparticles or dopants are located directly on the catalyst surface to create interfacial synergy with active sites on the oxide, but the enhancement effect may be compromised by insufficient hydrogen delivery to these sites. Here, we introduce a strategy to promote a ZnZrOx methanol synthesis catalyst by incorporating hydrogen activation and delivery functions through optimized integration of ZnZrOx and Pd supported on carbon nanotube (Pd/CNT). The CNT in the Pd/CNT + ZnZrOx system delivers hydrogen activated on Pd to a broad area on the ZnZrOx surface, with an enhancement factor of 10 compared to the conventional Pd-promoted ZnZrOx catalyst, which only transfers hydrogen to Pd-adjacent sites. In CO2 hydrogenation to methanol, Pd/CNT + ZnZrOx exhibits drastically boosted activity-the highest among reported ZnZrOx-based catalysts-and excellent stability over 600 h on stream test, showing potential for practical implementation.

16.
Antioxidants (Basel) ; 12(2)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36829890

RESUMEN

This study aimed to analyze the research trends on salivary oxidative stress associated with dental caries and to perform bibliometric approaches for existing publications on this association. A search was performed using the Web of Science Core Collection, without any restriction of language or publication year. The number of periodicals with the most published articles in this theme, most published authors and keywords were mapped; other metrics were also evaluated such as the countries that have more research on the subject and the period in which there were more publications on the subject. During the knowledge mapping, the most frequent experimental designs were analyzed, type of saliva collection, stage of caries disease, evaluated oxidative parameters were retrieved and analyzed from each manuscript. Between the 43 selected articles, the Journal of Clinical Pediatric Dentistry was the periodical appearing the most with 4 published articles. The authors who published the most were Celec, P., Tothova, L., Hegde, A.M., Shetty, S., Antoniali, C., and Pessan, JP with three articles each, and a total of 180 keywords representing the evolution of the theme. India and Asia were found to be the country and continent with most publications, respectively. Most articles collected non-stimulated total saliva, with total antioxidant capacity being the parameter most often evaluated. The type of study that appeared the most was cross-sectional studies, and articles published in the period of 2017-2022 were the most frequent. Studies show that dental caries can be associated to the changes in salivary oxidative biochemistry with an increase in lipid peroxidation, a biomarker of oxidative damage, and an increase in antioxidant capacity in chronic caries, in response to cariogenic challenge. Some studies evidence the reduction of lipid peroxidation after treatment of the carious lesion. Our findings reveal worldwide research trends, as well as a clearer knowledge of the evolution and future scenarios of this issue, also showing the mechanisms associating dental caries with changes in salivary oxidative biochemical parameters are not clear.

17.
Micromachines (Basel) ; 14(1)2023 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-36677276

RESUMEN

Graphene has unique properties that can be exploited for radiofrequency applications. Its characterization is key for the development of new graphene devices, circuits, and systems. Due to the two-dimensional nature of graphene, there are challenges in the methodology to extract relevant characteristics that are necessary for device design. In this work, the Thru-Reflect-Line (TRL) calibration was evaluated as a solution to extract graphene's electrical characteristics from 1 GHz to 65 GHz, where the calibration structures' requirements were analyzed. It was demonstrated that thick metallic contacts, a low-loss substrate, and a short and thin contact are necessary to characterize graphene. Furthermore, since graphene's properties are dependent on the polarization voltage applied, a backgate has to be included so that graphene can be characterized for different chemical potentials. Such characterization is mandatory for the design of graphene RF electronics and can be used to extract characteristics such as graphene's resistance, quantum capacitance, and kinetic inductance. Finally, the proposed structure was characterized, and graphene's resistance and quantum capacitance were extracted.

18.
Chemosphere ; 313: 137296, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36410523

RESUMEN

The tolerable aluminum (Al) intake levels for humans are constantly under review by regulatory agencies due to novel pre-clinical evidence on the neurotoxicity of prolonged Al exposure; however, little is known about the effects of Al on the spinal cord. This study aimed to investigate potential adverse effects on both spinal cord and systemic biochemical balance after prolonged exposure to a low dose of Al. Twenty adult rats were distributed in the control (distilled water) and exposed group (8.3 mg of AlCl3/kg/day). After 60 days, both blood and spinal cord samples were collected for oxidative stress and proteomic analyses. In plasma and erythrocytes, glutathione level was not different between groups; however, exposure to AlCl3 significantly decreased glutathione level in the spinal cord. Thiobarbituric acid reactive substances levels in the plasma and spinal cord of animals from the control group were significantly lower than those animals exposed to AlCl3. Exposure to AlCl3 significantly modulated the expression of proteins associated with the cell cycle, stimulus-response, cytoskeleton, nervous system regulation, protein activity, and synaptic signaling. Therefore, prolonged exposure to a low dose of Al triggered oxidative stress and proteomic changes that may affect spinal cord homeostasis.


Asunto(s)
Aluminio , Proteómica , Humanos , Ratas , Animales , Aluminio/metabolismo , Estrés Oxidativo , Antioxidantes/metabolismo , Glutatión/metabolismo , Médula Espinal/metabolismo
19.
Braz. j. infect. dis ; 27(4): 102791, 2023. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1513865

RESUMEN

ABSTRACT Introduction: Patients hospitalized with COVID-19 are often submitted to invasive procedures and they are at risk for hospital-associated adverse events. Objectives: To evaluate the epidemiological and clinical aspects of patients hospitalized with COVID-19; the occurrence of adverse events and the risk factors for mortality. Method: Cohort study that included adult patients hospitalized with a diagnosis of SAR-SCoV-2 infection, at the tertiary University Hospital of UNICAMP from March 2020 to March 2021. Patients were identified through the hospital epidemiological surveillance system and followed until discharge or death. Descriptive, comparative, and logistic regression analysis was performed. Results: 650 adult patients were included. The main adverse events identified were nosocomial infections (31.5%), renal failure (33.8%), thromboembolic and vascular events (12.6%). Mortality was higher among those with bloodstream infections (30.2% vs. 8.6%; p < 0.0001), ventilator-associated pneumonia (VAP, 52.5% vs. 12.3%; p < 0.0001), catheter associated urinary infection (27.3% vs. 7.2%; p < 0.0001); thromboembolic and vascular events (23.0% vs. 9.9%; p < 0.0001) and renal failure (81.3% vs. 20.9%; p < 0.0001). Klebsiella pneumoniae (15.6%), Pseudomonas aeruginosa (14.4%), Enterococcus faecalis (8.6%) were the most isolated bacteria. Logistic regression analysis identified age, (RR = 1.03; 95% CI 1.02 to 1.05); ICU admission (RR = 3.06; 95% CI 1.59 to 5.87), vasoactive drug use (RR = 3.1; 95% CI 1.79 to 4.82); renal failure (RR = 7.76; 95% CI 4.54 to 13.26); and VAP (RR = 2.2; 95% CI 1.23 to 3.96), independently associated with mortality. Conclusion: adverse events have an important impact on the evolution of patients with COVID-19, reinforcing the need for optimized prevention and control measures as an essential part of care for these patients.

20.
Arq. bras. cardiol ; 120(2): e20220151, 2023. tab, graf
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1420188

RESUMEN

Resumo Fundamento As complicações cardiovasculares da COVID-19 são aspectos importantes da patogênese e do prognóstico da doença. Evidências do papel prognóstico da troponina e da lesão miocárdica em pacientes hospitalizados com COVID-19 na América Latina são ainda escassos. Objetivos Avaliar a lesão miocárdica como preditor independente de mortalidade hospitalar e suporte ventilatório mecânico em pacientes hospitalizados, do registro brasileiro de COVID-19. Métodos Este estudo coorte é um subestudo do registro brasileiro de COVID-19, conduzido em 31 hospitais brasileiros de 17 cidades, de março a setembro de 2020. Os desfechos primários incluíram mortalidade hospitalar e suporte ventilatório mecânico invasivo. Os modelos para os desfechos primários foram estimados por regressão de Poisson com variância robusta, com significância estatística de p<0,05. Resultados Dos 2925 pacientes [idade mediana de 60 anos (48-71), 57,1%], 27,3% apresentaram lesão miocárdica. A proporção de pacientes com comorbidades foi maior nos pacientes com lesão miocárdica [mediana 2 (1-2) vs. 1 (0-20)]. Os pacientes com lesão miocárdica apresentaram maiores valores medianos de peptídeo natriurético cerebral, lactato desidrogenase, creatina fosfoquinase, N-terminal do pró-peptídeo natriurético tipo B e proteína C reativa em comparação a pacientes sem lesão miocárdica. Como fatores independentes, proteína C reativa e contagem de plaquetas foram relacionados com o risco de morte, e neutrófilos e contagem de plaquetas foram relacionados ao risco de suporte ventilatório mecânico invasivo. Os pacientes com níveis elevados de troponina apresentaram um maior risco de morte (RR 2,03, IC95% 1,60-2,58) e suporte ventilatório mecânico (RR 1,87;IC95% 1,57-2,23), em comparação àqueles com níveis de troponina normais. Conclusão Lesão cardíaca foi um preditor independente de mortalidade hospitalar e necessidade de suporte ventilatório mecânico em pacientes hospitalizados com COVID-19.


Abstract Background Cardiovascular complications of COVID-19 are important aspects of the disease's pathogenesis and prognosis. Evidence on the prognostic role of troponin and myocardial injury in Latin American hospitalized COVID-19 patients is still scarce. Objectives To evaluate myocardial injury as independent predictor of in-hospital mortality and invasive mechanical ventilation support in hospitalized patients, from the Brazilian COVID-19 Registry. Methods This cohort study is a substudy of the Brazilian COVID-19 Registry, conducted in 31 Brazilian hospitals of 17 cities, March-September 2020. Primary outcomes included in-hospital mortality and invasive mechanical ventilation support. Models for the primary outcomes were estimated by Poisson regression with robust variance, with statistical significance of p<0.05. Results Of 2,925 patients (median age of 60 years [48-71], 57.1% men), 27.3% presented myocardial injury. The proportion of patients with comorbidities was higher among patients with cardiac injury (median 2 [1-2] vs. 1 [0-2]). Patients with myocardial injury had higher median levels of brain natriuretic peptide, lactate dehydrogenase, creatine phosphokinase, N-terminal pro-brain natriuretic peptide, and C-reactive protein than patients without myocardial injury. As independent predictors, C-reactive protein and platelet counts were related to the risk of death, and neutrophils and platelet counts were related to the risk of invasive mechanical ventilation support. Patients with high troponin levels presented a higher risk of death (RR 2.03, 95% CI 1.60-2.58) and invasive mechanical ventilation support (RR 1.87, 95% CI 1.57-2.23), when compared to those with normal troponin levels. Conclusion Cardiac injury was an independent predictor of in-hospital mortality and the need for invasive mechanical ventilation support in hospitalized COVID-19 patients.

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