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1.
ACS Appl Nano Mater ; 6(21): 20006-20017, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37969783

RESUMO

Multifunctional textiles have emerged as a significant area of research due to their growing importance and diverse applications. The main requirement for these fabrics is electroconductivity, which is usually gained by incorporating conductive materials such as graphene into the textile structure. In this article, an electrochemical method was demonstrated to integrate different loadings of reduced graphene oxide (rGO) into fabrics for enhanced electrical conductivity. The process involves spray coating of graphene oxide (GO) onto the fabric, followed by in situ electrochemical reduction of GO, resulting in a coating layer of rGO nanosheets. The rGO-coated fabric exhibited exceptional Joule-heating capabilities, achieving 127 °C under a 9 V direct voltage with only 770 µg/cm2 of rGO loading. Moreover, the antibacterial properties of the rGO-coated fabric were demonstrated, showing a significant reduction rate of over 99.99% against both Bacillus subtilis and Escherichia coli. Joule-heating and antibacterial performances of the rGO-coated fabric were investigated over eight repeated cycles, demonstrating excellent repeatability. The simplicity of the fabrication method, along with the electrothermal and antibacterial effects of the rGO-coated fabric, makes it a promising material for various practical applications.

2.
Epidemiol Infect ; 151: e121, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37218612

RESUMO

Human monkeypox (mpox) virus is a viral zoonosis that belongs to the Orthopoxvirus genus of the Poxviridae family, which presents with similar symptoms as those seen in human smallpox patients. Mpox is an increasing concern globally, with over 80,000 cases in non-endemic countries as of December 2022. In this review, we provide a brief history and ecology of mpox, its basic virology, and the key differences in mpox viral fitness traits before and after 2022. We summarize and critique current knowledge from epidemiological mathematical models, within-host models, and between-host transmission models using the One Health approach, where we distinguish between models that focus on immunity from vaccination, geography, climatic variables, as well as animal models. We report various epidemiological parameters, such as the reproduction number, R0, in a condensed format to facilitate comparison between studies. We focus on how mathematical modelling studies have led to novel mechanistic insight into mpox transmission and pathogenesis. As mpox is predicted to lead to further infection peaks in many historically non-endemic countries, mathematical modelling studies of mpox can provide rapid actionable insights into viral dynamics to guide public health measures and mitigation strategies.


Assuntos
Mpox , Saúde Única , Animais , Humanos , Ecologia , Estudos Epidemiológicos , Modelos Epidemiológicos , Geografia , Mpox/epidemiologia
3.
Bioimpacts ; 13(2): 97-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37193077

RESUMO

Introduction: Chronic exposure to methamphetamine (Meth) results in permanent central nervous system damage and learning and memory dysfunction. This study aimed at investigating the therapeutic effects of bone marrow mesenchymal stem cells (BMMSCs) on cognitive impairments in Meth addicted rats and comparing intravenous (IV) delivery with intranasal (IN) delivery of BMMSCs. Methods: Adult Wistar rats were randomly divided into 6 groups; Control; Meth-addicted; IV-BMMSC (Meth administered and received IV BMMSCs); IN-BMMSC (Meth administered and received IN BMMSCs); IV-PBS (Meth administered and received IV Phosphate-buffered saline (PBS); IN-PBS (Meth administered and received IN PBS). BMMSCs were isolated, expanded in vitro, immunophenotyped, labeled, and administered to BMMSCs-treated groups (2 × 106 cells). The therapeutic effect of BMMSCs was measured using Morris water maze and Shuttle Box. Moreover, relapse-reduction was evaluated by conditioning place preference after 2 weeks following BMMSCs administration. The expression of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) in rat hippocampus was assessed using immunohistochemistry method. Results: Administration of BMMSCs caused a significant improvement in the learning and memory functions of Meth-addicted rats and reduced the relapse (P<0.01). In behavioral tests, comparison of IV and IN BMMSC-treated groups did not show any significant difference. Administration of BMMSCs improved the protein level of BDNF and GDNF in the hippocampus, as well as causing behavioral improvement (P<0.001). Conclusion: BMMSC administration might be a helpful and feasible method to treat Meth-induced brain injuries in rats and to reduce relapse. BMMSCs were significantly higher in IV-treated group compared to the IN route. Moreover, the expression of BDNF and GDNF was higher in IN-treated rats compared with IV treated group.

4.
Spat Spatiotemporal Epidemiol ; 43: 100524, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36460441

RESUMO

Accurate infectious disease models can help scientists understand how an ongoing disease epidemic spreads and forecast the course of epidemics more effectively. Considering various factors that affect the spread of a disease (e.g. geographical, social, domestic, and genetic), a class of individual-level models (ILMs) was developed to incorporate population heterogeneity. In these models, inferences are developed within a Bayesian Markov chain Monte Carlo (MCMC) framework, obtaining posterior estimates of model parameters. The issues of bias of parameter estimates, and methods for bias correction, have been widely studied with respect to many of the most established and commonly used statistical models and associated methods of parameter estimation. However, these methods are not directly applicable to infectious disease data. This paper investigates circumstances in which ILM parameter estimates may be biased in some simple disease system scenarios. Further, we aim to compare the performance of bias-corrected estimates of ILM parameters, using simulation, with the posterior estimates of the parameter. We also discuss the factors that affect the performance of these estimators.


Assuntos
Doenças Transmissíveis , Epidemias , Humanos , Teorema de Bayes , Doenças Transmissíveis/epidemiologia , Viés , Cadeias de Markov
6.
BMC Geriatr ; 22(1): 601, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35854209

RESUMO

INTRODUCTION: Polypharmacy is commonly associated with adverse health outcomes. There are currently no meta-analyses of the prevalence of polypharmacy or factors associated with polypharmacy. We aimed to estimate the pooled prevalence of polypharmacy and factors associated with polypharmacy in a systematic review and meta-analysis. METHODS: MEDLINE, EMBASE, and Cochrane databases were searched for studies with no restrictions on date. We included observational studies that reported on the prevalence of polypharmacy among individuals over age 19. Two reviewers extracted study characteristics including polypharmacy definitions, study design, setting, geography, and participant demographics. The risk of bias was assessed using the Newcastle-Ottawa Scales. The main outcome was the prevalence of polypharmacy and factors associated with polypharmacy prevalence. The pooled prevalence estimates of polypharmacy with 95% confidence intervals were determined using random effects meta-analysis. Subgroup analyses were undertaken to evaluate factors associated with polypharmacy such as polypharmacy definitions, study setting, study design and geography. Meta-regression was conducted to assess the associations between polypharmacy prevalence and study year. RESULTS: 106 full-text articles were identified. The pooled estimated prevalence of polypharmacy in the 54 studies reporting on polypharmacy in all medication classes was 37% (95% CI: 31-43%). Differences in polypharmacy prevalence were reported for studies using different numerical thresholds, study setting, and publication year. Sex, study geography, study design and geographical location were not associated with differences in polypharmacy prevalence. DISCUSSION: Our review highlights that polypharmacy is common particularly among older adults and those in inpatient settings. Clinicians should be aware of populations who have an increased likelihood of experiencing polypharmacy and efforts should be made to review the appropriateness of prescribed medications and occurrence of adverse effects potentially associated with polypharmacy. CONCLUSIONS AND IMPLICATIONS: Clinicians should be aware of the common occurrence of polypharmacy and undertake efforts to minimize inappropriate polypharmacy whenever possible.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Polimedicação , Idoso , Humanos , Prevalência , Projetos de Pesquisa
7.
J Electroanal Chem (Lausanne) ; 895: None, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34404986

RESUMO

The importance of hydroxyl ions concentration measurement in solution necessitates the development of suitable and simple sensing methods for online detection. To address this need, an electrochemical sensor was developed using nickel as the working electrode that enabled specificity towards hydroxyl ions and their successfully quantification. The electrochemical reaction between nickel and hydroxyl ions in solution generates a current which is proportional to the concentration of hydroxyl ions and consequently is also correlated to the pH of the solution. Cyclic voltammetry and chronoamperometry techniques were used to prepare and activate the nickel electrode for detection. The analysis of chronoamperometric experiments in different solutions exhibited three calibration curves between the current and hydroxyl ion concentrations for three regions in the range of 0.3 µM to 4.8 M with a short response time of 14 s. Up to now, no other hydroxyl ion sensor has been reported that can reach this detection limit. This sensor also holds promise to work perfectly in highly alkaline environments where only costly commercial electrodes are available to quantify pH. The results show three linear calibration curves between the current and pH of the solution over the pH range of 7.4 to 14.6. In addition to the wide detection range, the sensor exhibits a relative standard deviation percentage lower than 7% over 9 months of experiments, confirming repeatability of measurements and stability of the electrode. The potential of the proposed method to measure pH in real applications was demonstrated by testing the sensor in solutions containing urea, nitrates, phosphates, and sulfates.

8.
Iran Biomed J ; 24(2): 89-98, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31677610

RESUMO

Background: Recent studies have shown that bone marrow mesenchymal stem cells (BMSCs) have a putative ability to promote neurogenesis and produce behavioral and functional improvement. Our previous study demonstrated that co-treatment of granulocyte colony-stimulating factor (G-CSF) and BMSCs have beneficial effects on Parkinson's models. The main purpose of this research was to investigate the effects of these two factors on oxidative stress factors in the brain of Parkinson's rat. Methods: Adult male Wistar rats (weighing 200­250 g) were used and randomly divided into five groups of seven each. To create the Parkinson's model, 6-OHDA was injected into the left substantia nigra pars compacta. The BMSCs (2 × 106) and G-CSF (75 µg/kg) were used for treatment after creating the PD model. After four weeks, the brains of rats were removed and processed for immunohistochemical studies, such as tyrosine hydroxylase-positive neurons as well as analysis of oxidative stress factors. Results: The results showed that the injected BMSCs could cross the BBB. The injected cells are also able to settle in different areas of the brain. Analyses of the brain oxidative stress factors showed that G-CSF and BMSCs reduced the expression of malondialdehyde and induced the activity of superoxide dismutase, glutathione, and peroxidase ferric reducing ability of plasma. Conclusion: Co-administration of G-CSF and BMSC reduced the expression of pro-inflammatory cytokines and induced the activity of antioxidant enzymes; however, neurogenesis increased in the brain.


Assuntos
Fator Estimulador de Colônias de Granulócitos/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Neurogênese/fisiologia , Estresse Oxidativo/fisiologia , Doença de Parkinson/terapia , Animais , Barreira Hematoencefálica/fisiologia , Encéfalo/patologia , Modelos Animais de Doenças , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Oxidopamina/toxicidade , Doença de Parkinson/patologia , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Serina-Treonina Quinases TOR/metabolismo
9.
Int J Reprod Biomed ; 14(10): 649-656, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27921089

RESUMO

L-carnitine (LC) is an antioxidant with the ability to promote the growth in vitro embryo. OBJECTIVE: The goal was to evaluate the effect of LC on some indicators of embryo development and blastocyst quality including zona pellucid (ZP) thickness, the hatching of blastocysts and their cell numbers. MATERIALS AND METHODS: Mouse embryos were randomly divided into five groups and incubated with different concentrations of LC (I; 0, II; 0.5, III; 1, IV; 2 and V; 4 mg/ml) from 2-cell to hatched blastocyst. The percentage of blastocysts and hatched blastocysts was calculated. Blastocysts ZP thickness was measured and the number of blastocyst cells was counted using Hoechst and propidium iodide (PI) staining. RESULTS: The results showed concentration of 0.5 mg/ml of LC had an antioxidant effect as in this group, the percentage of blastocysts and hatched blactocysts (p=0.01), the ZP thickness (p=0.00) and the number of blastocyst inner cell mass were significantly more favorable than the control group (p=0.03); and concentration of 4 mg/ml of LC had a toxic effect on embryo development and blastocyst quality (p=0.00). CONCLUSION: The results suggest that LC may increase the number of blastocyst cells, which probably helps to expand the blastocyst and thinning of the ZP thickness and, therefore, creating a successful hatching for implantation.

10.
Iran J Basic Med Sci ; 19(12): 1318-1324, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28096964

RESUMO

OBJECTIVES: Granulocyte-colony stimulating factor (G-CSF) is used in clinical practice for the treatment of neutropenia and to stimulate generation of hematopoietic stem cells in bone marrow donors. In the present study, the ability of G-CSF in mobilizing exogenous bone marrow stem cells (BMSCs) from peripheral blood into the brain was tested. We for the first time injected a small amount of BMSCs through the tail vein. MATERIALS AND METHODS: We choose 25 male Wistar rats (200-250 g) were lesioned by 6-OHDA injected into the left substantia nigra, pars compacta (SNpc). G-CSF (70 µg/kg/day) was given from the 7th day after lesion for five days. The BMSCs (2×105) were injected through the dorsal tail vein on the 7th day after lesion. RESULTS: The number of rotations was significantly lower in the stem cell therapy group than in the control group. In the third test in the received G-CSF and G-CSF+stem cells groups, animals displayed significant behavioral recovery compared with the control group (P<0.05). There was a significant difference in the average of dopaminergic neurons in SNpc between the control group and G-CSF and G-CS+stem cells groups. We didn't detect any labeling stem cells in SNpc. CONCLUSION: G-CSF can't mobilize low amounts of exogenous BMSCs from the blood stream to injured SNpc. But G-CSF (70 µg/kg) is more neuroprotective than BMSCs (2×105 number[w1] of BMSCs). Results of our study suggest that G-CSF alone is more neuroprotective than BMSCs.

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