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1.
Electrochim Acta ; 451: 142271, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36974119

RESUMO

Fast, sensitive, simple, and cheap sensors are highly desirable to be applied in the health system because they improve point-of-care diagnostics, which can reduce the number of cases of infection or even deaths. In this context, here we report the development of a label-free genosensor using a screen-printed electrode modified with 2D-carbonylated graphitic carbon nitride (c-g-C3N4), poly(diallyldimethylammonium) chloride (PDDA), and glutathione-protected gold nanoparticles (GSH-AuNPs) for photoelectrochemical (PEC) detection of SARS-CoV-2. We also made use of Arduino and 3D printing to miniaturize the sensor device. The electrode surface was characterized by AFM and SEM techniques, and the gold nanoparticles by UV-Vis spectrophotometry. For SARS-CoV-2 detection, capture probe DNA was immobilized on the electrode surface. The hybridization of the final genosensor was tested with a synthetic single-strand DNA target and with natural saliva samples using the photoelectrochemistry method. The device presented a linear range from 1 to 10,000 fmol L-1 and a limit of detection of 2.2 and 3.4 fmol L-1 using cpDNA 1A and 3A respectively. The sensibility and accuracy found for the genosensor using cpDNA 1A using biological samples were 93.3 and 80% respectively, indicating the potential of the label-free and portable genosensor to detect SARS-CoV-2 RNA in saliva samples.

2.
BMC Anesthesiol ; 23(1): 190, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264317

RESUMO

BACKGROUND: The American Society of Anesthesiologists (ASA) has an impressive array of professional perioperative guidelines but has not issued a guideline specific to perioperative blood glucose management and does not delve into the topic in their other guidelines. CASE REPORT: We experienced a perioperative case that highlights the potential difficulty of glucose management in this setting. During anesthetic induction for an orthopedic foot surgery, as the medication was infusing, an IDDM 1 (insulin dependent diabetes mellitus type 1) patient expressed feeling that her blood sugar level was low. Her finger stick after induction showed severe hypoglycemia with a blood glucose of 34 mg/dL. The hypoglycemia was treated with intravenous glucose and further closely monitored. CONCLUSIONS: This case led us to revisit the different perioperative guidelines and recommendations for diabetic patients and this manuscript aims to highlight the similarities and discrepancies among the different published recommendations. This case highlights the value of utilizing insulin pump infusions in the perioperative setting when available.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Near Miss , Humanos , Feminino , Glicemia , Glucose/uso terapêutico , Hipoglicemiantes/efeitos adversos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina
3.
World J Microbiol Biotechnol ; 39(10): 261, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37500990

RESUMO

The current industrial and human activities scenario has accelerated the widespread use of endocrine-disrupting compounds (EDCs), which can be found in everyday products, including plastic containers, bottles, toys, cosmetics, etc., but can pose a severe risk to human health and the environment. In this regard, fungal bioremediation appears as a green and cost-effective approach to removing pollutants from water resources. Besides, immobilizing fungal cells onto nanofibrous membranes appears as an innovative strategy to improve remediation performance by allowing the adsorption and degradation to occur simultaneously. Herein, we developed a novel nanostructured bioremediation platform based on polyacrylonitrile nanofibrous membrane (PAN NFM) as supporting material for immobilizing an endophytic fungus to remove bisphenol A (BPA), a typical EDC. The endophytic strain was isolated from Handroanthus impetiginosus leaves and identified as Phanerochaete sp. H2 by molecular methods. The successful assembly of fungus onto the PAN NFM surface was confirmed by scanning electron microscopy (SEM). Compared with free fungus cells, the PAN@H2 NFM displayed a high BPA removal efficiency (above 85%) at an initial concentration of 5 ppm, suggesting synergistic removal by simultaneous adsorption and biotransformation. Moreover, the biotransformation pathway was investigated, and the chemical structures of fungal metabolites of BPA were identified by ultra-high performance liquid chromatography - high-resolution mass (UHPLC-HRMS) analysis. In general, our results suggest that by combining the advantages of enzymatic activity and nanofibrous structure, the novel platform has the potential to be applied in the bioremediation of varied EDCs or even other pollutants found in water resources.


Assuntos
Nanofibras , Tabebuia , Poluentes Químicos da Água , Humanos , Nanofibras/química , Fenóis/análise , Fungos , Poluentes Químicos da Água/análise
4.
Epilepsia ; 62(1): 41-50, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258109

RESUMO

OBJECTIVE: Our epilepsy population recently experienced the acute effects of the COVID-19 pandemic in New York City. Herein, we aimed to determine patient-perceived seizure control during the surge, specific variables associated with worsened seizures, the prevalence of specific barriers to care, and patient-perceived efficacy of epilepsy care delivered via telephone and live video visits during the pandemic. METHODS: We performed a cross-sectional questionnaire study of adult epilepsy patients who had a scheduled appointment at a single urban Comprehensive Epilepsy Center (Montefiore Medical Center) between March 1, 2020 and May 31, 2020 during the peak of the COVID-19 pandemic in the Bronx. Subjects able to answer the questionnaire themselves in English or Spanish were eligible to complete a one-time survey via telephone or secure online platform (REDCap). RESULTS: Of 1212 subjects screened, 675 were eligible, and 177 adequately completed the questionnaire. During the COVID-19 pandemic, 75.1% of patients reported no change in seizure control, whereas 17.5% reported that their seizure control had worsened, and 7.3% reported improvement. Subjects who reported worsened seizure control had more frequent seizures at baseline, were more likely to identify stress and headaches/migraines as their typical seizure precipitants, and were significantly more likely to report increased stress related to the pandemic. Subjects with confirmed or suspected COVID-19 did not report worsened seizure control. Nearly 17% of subjects reported poorer epilepsy care, and 9.6% had difficulty obtaining their antiseizure medications; these subjects were significantly more likely to report worse seizure control. SIGNIFICANCE: Of the nearly 20% of subjects who reported worsened seizure control during the COVID-19 pandemic, stress and barriers to care appear to have posed the greatest challenge. This unprecedented pandemic exacerbated existing and created new barriers to epilepsy care, which must be addressed.


Assuntos
Atitude Frente a Saúde , COVID-19/complicações , COVID-19/psicologia , Epilepsia/psicologia , Epilepsia/terapia , Acessibilidade aos Serviços de Saúde , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , População Urbana , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/uso terapêutico , Estudos Transversais , Epilepsia/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque , Satisfação do Paciente , Consulta Remota , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
5.
Drug Dev Ind Pharm ; 47(10): 1556-1567, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34821528

RESUMO

The use of polymeric blends is a potential strategy to obtain novel nanotechnological formulations aiming at drug delivery systems. Saquinavir, an antiretroviral drug, was chosen as a model drug for the development of new stable liquid formulations with unpleasant taste masking properties. Three formulations containing different polymeric ratios (1:3, 1:1 and 3:1) were prepared and properly characterized by particle size distribution, zeta potential, pH, drug content and encapsulation efficiency measurements. The stability was verified by monitoring the zeta potential, particle size distribution, polydispersity index and drug content by 90 days. The light backscattering analysis was used to early identify possible phenomena of instability in the formulations. The in vitro drug release and saquinavir cytotoxicity were evaluated. The in vitro and in vivo taste masking properties were studied using an electronic tongue and a human sensory panel. All formulations presented nanometric sizes around 200 nm and encapsulation efficiency above 99%. The parameters evaluated for stability remained constant throughout 90 days. The in vitro tests showed a controlled drug release and absence of toxic effects on human T lymphocytes. The electronic tongue experiment showed taste differences for all formulations in comparison to drug solutions, with a more pronounced difference for the formulation with higher polycaprolactone content (3:1). This formulation was chosen for in vivo sensory panel evaluation which results corroborated the electronic tongue experiments. In conclusion, the polymer blend nanoformulation developed herein showed the promising application to incorporate drugs aiming at pharmaceutical taste-masking properties.


Assuntos
Saquinavir , Paladar , Humanos , Preparações Farmacêuticas/química , Poliésteres , Polímeros , Saquinavir/farmacologia
6.
Telemed J E Health ; 27(4): 468-471, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33017270

RESUMO

Background: The coronavirus disease 2019 (COVID-19) pandemic is straining health care worldwide with >31 million confirmed cases. Currently, 1 in every 100 U.S. residents and 245,000 in New York City are confirmed positive. The Bronx, with high-risk comorbidities, due in part to socioeconomic factors, has seen disproportionately higher rates of COVID-19-related complications. Poor health care access is exacerbated as in-person visits now pose viral transmission risk. There has been limited discourse regarding widespread disparities underlying transitions to telemedicine. Methods: We review perspectives in recent literature on telemedicine and its potential within neurology. Results: While telemedicine has reduced strain on in-person visits, preliminary reflections highlight implementation successes and challenges. Conclusions: To provide effective care beyond this crisis, fundamental changes in training, technological accessibility, and health care policy are needed. We propose open access to telehealth training, screening of patient's potential technological inequities and socioeconomic insecurities, and advocacy to secure broad long-term access to telehealth care.


Assuntos
COVID-19 , Acessibilidade aos Serviços de Saúde , Telemedicina , Humanos , Cidade de Nova Iorque , Pandemias
7.
Am J Med Genet C Semin Med Genet ; 184(4): 1078-1091, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33319501

RESUMO

The early detection of congenital anomaly epidemics occurs when comparing current with previous frequencies in the same population. The success of epidemiologic surveillance depends on numerous factors, including the accuracy of the rates available in the base period, wide population coverage, and short periodicity of analysis. This study aims to describe the Latin American network of congenital malformation surveillance: ReLAMC, created to increase epidemiologic surveillance in Latin America. We describe the main steps, tasks, strategies used, and preliminary results. From 2017 to 2019, five national registries (Argentina [RENAC], Brazil [SINASC/SIM-BRS], Chile [RENACH], Costa Rica [CREC], Paraguay [RENADECOPY-PNPDC]), six regional registries (Bogotá [PVSDC-Bogota], Cali [PVSDC-Cali], Maule [RRMC SSM], Nicaragua [SVDC], Nuevo-León [ReDeCon HU], São Paulo [SINASC/SIM-MSP]) and the ECLAMC hospital network sent data to ReLAMC on a total population of 9,152,674 births, with a total of 101,749 malformed newborns (1.1%; 95% CI 1.10-1.12). Of the 9,000,651 births in countries covering both live and stillbirths, 88,881 were stillborn (0.99%; 95% CI 0.98-0.99), and among stillborns, 6,755 were malformed (7.61%; 95% CI 7.44-7.79). The microcephaly rate was 2.45 per 10,000 births (95% CI 2.35-2.55), hydrocephaly 3.03 (2.92-3.14), spina bifida 2.89 (2.78-3.00), congenital heart defects 15.53 (15.27-15.79), cleft lip 2.02 (1.93-2.11), cleft palate and lip 2.77 (2.66-2.88), talipes 2.56 (2.46-2.67), conjoined twins 0.16 (0.14-0.19), and Down syndrome 5.33 (5.18-5.48). Each congenital anomaly showed heterogeneity in prevalence rates among registries. The harmonization of data in relation to operational differences between registries is the next step in developing the common ReLAMC database.


Assuntos
Anormalidades Congênitas , Chile , Humanos , Recém-Nascido , América Latina/epidemiologia , Prevalência , Sistema de Registros
8.
Epilepsia ; 61(3): 528-538, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32096225

RESUMO

OBJECTIVE: The use of the Internet for health-related questions is increasing, but it is not clear whether individuals can understand the information available online. Most health organizations recommend that health educational materials (HEMs) be written below the sixth grade reading level. This study was designed to evaluate the readability level of available online HEMs pertaining to traumatic brain injury (TBI), epilepsy, and posttraumatic epilepsy (PTE). METHODS: This cross-sectional readability assessment included HEMs from TBI and epilepsy stakeholder organizations and those obtained from four Internet searches. The search strategy was designed to replicate a nonmedical individual's keyword searches. Each HEM was assessed with an online automated readability tool using three indices (Flesch Reading Ease Score, Flesch-Kincaid Grade Level, and Simple Measure of Gobbledygook). Findings were compared as a function of organization type (journalistic news or health organization), targeted medical condition (TBI, epilepsy, or PTE), or content topic (patient health education, clinical research education, or both). RESULTS: Readability analysis of 405 identified HEMs revealed scores above the sixth grade reading level recommendation. Only 6.2% of individual HEMs met the sixth grade recommendation. Journalistic news organizations' HEMs had similar readability levels to health organizations' HEMs. PTE-related HEMs required the highest readability level, >11th grade (P < .001). There were significant differences in the readability scores (P < .01 for all indices) among HEMs with information on health education, research education, or both topics. The highest required readability level (>12 grade level) was for HEMs that included both health and research education. SIGNIFICANCE: The majority of TBI-, epilepsy-, and PTE-related online HEMs do not meet the sixth grade reading recommendation. Improving the readability of HEMs may advance health literacy around TBI, epilepsy, and PTE, leading to more effective participant recruitment/retention strategies for future antiepileptogenesis trials in persons with TBI and perhaps better patient-centered outcomes.


Assuntos
Lesões Encefálicas Traumáticas , Compreensão , Informação de Saúde ao Consumidor , Epilepsia Pós-Traumática , Epilepsia , Internet , Centers for Disease Control and Prevention, U.S. , Humanos , MedlinePlus , Sociedades Médicas , Estados Unidos , United States Department of Veterans Affairs
9.
Mycoses ; 63(5): 494-499, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32163641

RESUMO

BACKGROUND: Dermatophytosis is one of the most frequent superficial mycoses in the world. MAIN AIM: To describe the cases of skin dermatophytosis and its main aetiologic agents in patients referred to a Mycological Reference Laboratory in Medellín, Colombia. METHODS: A retrospective study was carried out with records of patients referred between 1994 and 2016 to the Corporación para Investigaciones Biológicas (CIB), Medellín-Colombia, because of clinical suspicion of skin dermatophytosis. RESULTS: Of a total of 5628 clinical records of patients with suspicion of skin dermatophytosis analysed, 2780 (49.4%) had a proven or probable dermatophytosis diagnosis, 2774 cultures were performed, and aetiologic agents were isolated in 2576 samples (92.9%). The most frequently isolated aetiologic agents were Trichophyton rubrum (44.3%), followed by Trichophyton mentagrophytes complex (33.3%), Epidermophyton floccosum (12.4%), Nannizzia gypseum complex (5.7%, formerly Microsporum gypseum), Microsporum canis (3.5%) and Trichophyton tonsurans (0.8%). The most frequent clinical forms were tinea pedis (72.7%) and tinea corporis (12.7%). In addition, a group of patients (0.9%) developed mixed infections by two dermatophyte agents and another (4.1%) developed infections in more than one anatomical site. CONCLUSIONS: The results of the present study are coherent with previous reports where T rubrum and T mentagrophytes complex were the main causative agents of dermatophytosis. However, the increased incidence of N gypsea complex over M canis is worth highlighting.


Assuntos
Dermatomicoses/epidemiologia , Fungos/isolamento & purificação , Tinha/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Arthrodermataceae/classificação , Arthrodermataceae/isolamento & purificação , Criança , Pré-Escolar , Colômbia/epidemiologia , Dermatomicoses/microbiologia , Epidermophyton/classificação , Epidermophyton/isolamento & purificação , Fungos/classificação , Humanos , Lactente , Masculino , Microsporum/classificação , Microsporum/isolamento & purificação , Pessoa de Meia-Idade , Estudos Retrospectivos , Pele/microbiologia , Pele/patologia , Tinha/epidemiologia , Trichophyton/classificação , Trichophyton/isolamento & purificação , Adulto Jovem
10.
Sensors (Basel) ; 20(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033030

RESUMO

A potentiometric E-tongue system based on low-selective polymeric membrane and chalcogenide-glass electrodes is employed to monitor the taste-and-odor-causing pollutants, geosmin (GE) and 2-methyl-isoborneol (MIB), in drinkable water. The developed approach may permit a low-cost monitoring of these compounds in concentrations near the odor threshold concentrations (OTCs) of 20 ng/L. The experiments demonstrate the success of the E-tongue in combination with partial least squares (PLS) regression technique for the GE/MIB concentration prediction, showing also the possibility to discriminate tap water samples containing these compounds at two concentration levels: the same OTC order from 20 to 100 ng/L and at higher concentrations from 0.25 to 10 mg/L by means of PLS-discriminant analysis (DA) method. Based on the results, developed multisensory system can be considered a promising easy-to-handle tool for express evaluation of GE/MIB species and to provide a timely detection of alarm situations in case of extreme pollution before the drinkable water is delivered to end users.


Assuntos
Canfanos/isolamento & purificação , Água Potável/análise , Naftóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Canfanos/química , Nariz Eletrônico/tendências , Humanos , Naftóis/química , Potenciometria/tendências , Poluentes Químicos da Água/química
11.
Neurobiol Dis ; 123: 137-144, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30031158

RESUMO

The increased focus on stakeholder engagement in determining the aims, design, conduct of research and dissemination of results is substantially changing the biomedical research paradigm. In this era of patient-centered care, incorporating participatory action research methodology into large-scale multi-center studies is essential. The adoption of community engagement facilitates meaningful contribution to the design and implementation of clinical studies. Consequently, encouraging citizen participation and involving key organizations may guide the effective development of future clinical research protocols. Here, we discuss our experience in engaging individuals, their caregivers, as well as scientific and consumer organizations in public outreach and knowledge transfer to assist in the development of effective strategies for recruitment and retention in a future post-traumatic epilepsy prevention randomized controlled trial within the National Institute of Neurologic Disorders and Stroke Center Without Walls, Epilepsy Bioinformatics Study for Antiepileptogenic Therapy (EpiBioS4Rx). The study includes a Public Engagement Core with a diverse consortium of stakeholder partners. Based on the Core's ongoing experience, it is recommended that multicenter studies integrate a participatory action research based approach to harness the benefits of a collective inquiry. The blueprint created by the EpiBioS4Rx Public Engagement Core is a resource that could be applied in other areas of biomedical research.


Assuntos
Lesões Encefálicas Traumáticas/prevenção & controle , Pesquisa Participativa Baseada na Comunidade , Epilepsia Pós-Traumática/prevenção & controle , Participação do Paciente , Animais , Lesões Encefálicas Traumáticas/complicações , Cuidadores , Biologia Computacional , Epilepsia Pós-Traumática/etiologia , Humanos , Participação dos Interessados
12.
Sensors (Basel) ; 19(23)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766686

RESUMO

"Electronic tongues", "taste sensors", and similar devices (further named as "multisensor systems", or MSS) have been studied and applied mostly for the analysis of edible analytes. This is not surprising, since the MSS development was sometimes inspired by the mainstream idea that they could substitute human gustatory tests. However, the basic principle behind multisensor systems-a combination of an array of cross-sensitive chemical sensors for liquid analysis and a machine learning engine for multivariate data processing-does not imply any limitations on the application of such systems for the analysis of inedible media. This review deals with the numerous MSS applications for the analysis of inedible analytes, among other things, for agricultural and medical purposes.


Assuntos
Técnicas Biossensoriais/instrumentação , Eletrônica/instrumentação , Nariz Eletrônico , Desenho de Equipamento/instrumentação , Humanos , Paladar/fisiologia , Língua/fisiologia
14.
J Nanosci Nanotechnol ; 18(7): 4876-4883, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442668

RESUMO

Cellulose, the main component of plant cell walls, is a biopolymer widely used for industrial applications, including, food, paper and textile fabrication. More recently, hybrid materials composed of cellulose nanostructures and metal nanoparticles have been applied in diverse areas such as medical and pharmaceutical applications. In this work, cellulose-silver nanoparticles (AgNPs) hybrid material was synthesized and the influence of cellulose, employed as a stabilizer agent, was investigated. Specifically, cellulose whiskers (CCW) were extracted from commercial cotton fibers by acid hydrolysis route, while the AgNPs were synthesized by reducing silver salt using sodium citrate and/or sodium borohydride in the presence of CCW. The synthesized AgNPs/CCW nanocomposites were characterized in terms of morphology, chemical composition, surface charge and antibacterial properties. The varied synthetic routes generated AgNPs with different morphological characteristics in terms of size, shape and coalescence. The particularity of each sample resulted in distinct behaviors for the tested bacteria. Syntheses employing CCW resulted in AgNPs/CCW nanocomposites with controlled morphology and improved antibacterial effects against E. coli (Gram-negative) and S. aureus (Gram-positive), indicating CCW as a promising compound to be used in the syntheses of silver and other metal nanoparticles with controlled morphology and antibacterial properties.


Assuntos
Antibacterianos/farmacologia , Celulose , Nanopartículas Metálicas , Prata , Antibacterianos/química , Escherichia coli , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
15.
Sensors (Basel) ; 18(4)2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29614771

RESUMO

Ammonia (NH3) gas is a prominent air pollutant that is frequently found in industrial and livestock production environments. Due to the importance in controlling pollution and protecting public health, the development of new platforms for sensing NH3 at room temperature has attracted great attention. In this study, a sensitive NH3 gas device with enhanced selectivity is developed based on zinc oxide nanofibers (ZnO NFs) decorated with poly(styrene sulfonate) (PSS) and operated at room temperature. ZnO NFs were prepared by electrospinning followed by calcination at 500 °C for 3 h. The electrospun ZnO NFs are characterized to evaluate the properties of the as-prepared sensing materials. The loading of PSS to prepare ZnO NFs/PSS composite is also optimized based on the best sensing performance. Under the optimal composition, ZnO NFs/PSS displays rapid, reversible, and sensitive response upon NH3 exposure at room temperature. The device shows a dynamic linear range up to 100 ppm and a limit of detection of 3.22 ppm and enhanced selectivity toward NH3 in synthetic air, against NO2 and CO, compared to pure ZnO NFs. Additionally, a sensing mechanism is proposed to illustrate the sensing performance using ZnO NFs/PSS composite. Therefore, this study provides a simple methodology to design a sensitive platform for NH3 monitoring at room temperature.

17.
Ecotoxicol Environ Saf ; 144: 138-147, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28609663

RESUMO

The advance of nanotechnology has enabled the development of materials with optimized properties for applications in agriculture and environment. For instance, nanotechnology-based fertilizers, such as the candidate hydroxyapatite (HAp) nanoparticles (Ca10(PO4)6(OH)2), can potentially increase the food production by rationally supplying phosphorous to crops, although with inferior mobility in the environment (when compared to the soluble counterparts), avoiding eutrophication. Nonetheless, the widespread consumption of nanofertilizers also raises concern about feasible deleterious effects caused by their release in the environment, which ultimately imposes risks to aquatic biota and human health. Nanoparticles characteristics such as size, shape, surface charge and chemical functionality strongly alter how they interact with the surrounding environment, leading to distinct levels of toxicity. This investigation aimed to compare the toxicity of different HAp nanoparticles, obtained by two distinct chemical routes, against algae Pseudokirchneriella subcapitata, which composes the base of the aquatic trophic chain. The as synthesized HAp nanoparticles obtained by co-precipitation and co-precipitation followed by hydrothermal method were fully characterized regarding structure and morphology. Toxicity tests against the microalgae were carried out to evaluate the growth inhibition and the morphological changes experienced by the exposition to HAp nanoparticles. The results showed that high concentrations of coprecipitated HAp samples significantly decreased cell density and caused morphological changes on the algal cells surface when compared to HAp obtained by hydrothermal method. HAp nanoparticles obtained with dispersing agent ammonium polymethacrylate (APMA) indicated negligible toxic effects for algae, due to the higher dispersion of HAp in the culture medium as well as a reduced shading effect. Therefore, HAp nanoparticles obtained by the latter route can be considered a potential source of phosphorous for agricultural crops in addition to reduce eutrophication.


Assuntos
Clorófitas/efeitos dos fármacos , Durapatita/toxicidade , Microalgas/efeitos dos fármacos , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade , Relação Dose-Resposta a Droga , Durapatita/química , Eutrofização , Humanos , Nanoestruturas/química , Propriedades de Superfície , Poluentes Químicos da Água/química
18.
Environ Monit Assess ; 189(7): 352, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28646437

RESUMO

Several mutagenic agents may be present in substances released in the environment, which may cause serious environmental impacts. Among these substances, there is a special concern regarding the widespread use of silver nanoparticles (AgNP) in several products due to their widely known bactericidal properties, including in the medical field and the food industry (e.g., active packaging). The assessment of the effects of AgNP released in the environment, having different concentrations, sizes, and being associated or not to other types of materials, including polymers, is therefore essential. In this research, the objective was to evaluate the genotoxic and cytotoxic effects of AgNP (size range between 2 and 8 nm) on root meristematic cells of Allium cepa (A. cepa). Tests were carried out in the presence of colloidal solution of AgNP and AgNP mixed with carboxymethylcellulose (CMC), using distinct concentrations of AgNP. As a result, when compared to control samples, AgNP induced a mitotic index decrease and an increase of chromosomal aberration number for two studied concentrations. When AgNP was in the presence of CMC, no cytotoxic potential was verified, but only the genotoxic potential for AgNP dispersion having concentration of 12.4 ppm.


Assuntos
Allium/efeitos dos fármacos , Carboximetilcelulose Sódica/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Aberrações Cromossômicas , Dano ao DNA , Monitoramento Ambiental , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Cebolas/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos
19.
J Sports Sci Med ; 15(1): 111-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26957933

RESUMO

The purpose of this study was to measure the acute effects of pre-exhaustion vs. traditional exercise order on neuromuscular performance and sEMG in trained men. Fourteen young, healthy, resistance trained men (age: 25.5 ± 4.0 years, height: 174.9 ± 4.1 cm, and total body mass: 80.0 ± 11.1 kg) took part of this study. All tests were randomized and counterbalanced for all subjects and experimental conditions. Volunteers attended one session in the laboratory. First, they performed ten repetition maximum (10RM) tests for each exercise (bench press and triceps pushdown) separately. Secondly, they performed all three conditions at 10RM: pre-test (bench press and triceps pushdown, separately), pre-exhaustion (triceps pushdown+bench press, PE) and traditional (bench press+triceps pushdown, TR), and rested 30 minutes between conditions. Results showed that pre-test was significantly greater than PE (p = 0.031) but not different than TR, for total volume load lifted. There was a significant difference between the pre-test and the time-course of lactate measures (p = 0.07). For bench press muscle activity of the pectoralis major, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). Also, for muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.001, PE: p = 0.005, and TR: p = 0.006). For triceps pushdown, muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). For RPE, there were no significant differences between PE and TR (p = 0.15). Our results suggest that exercise order decreases repetitions performed, however, neuromuscular fatigue, lactate, and RPE are not impacted. The lack of difference in total volume load lifted between PE and TR might explain, at least in part, the similar metabolic and perceptual responses. Key pointsThe effects of different exercise order schemes (e.g. PE and TR) on muscle activity and strength performance indicated that similar responses were observed when comparing these schemes.Strength and conditioning coaches should consider these results when prescribing resistance training programs.The primary target (e.g. muscle group) of the training session should trained first, when fatigue level low, in order to maximize training outcomes.

20.
J Nanosci Nanotechnol ; 15(3): 2148-56, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26413633

RESUMO

This paper reports the antibacterial effect and physico-chemical characterization of films containing silver nanoparticles for use as food packaging. Two masterbatches (named PEN and PEC) con- taining silver nanoparticles embedded in distinct carriers (silica and titanium dioxide) were mixed with low-density polyethylene (LDPE) in different compositions and extruded to produce plain films. These films were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). The morphology of the films showed the formation of agglomerates of nanoparticles in both PEN and PEC composites. X-ray analyses confirmed the presence of SiO2 in PEN samples and TiO2 in PEC samples. Thermal analyses indicated an increase in thermal stability of the PEC compositions. The antimicrobial efficacy was determined by applying the test strain for Escherichia coli and Staphylococcus aureus, according to the Japanese Industrial Standard Method (JIS Z 2801:2000). The films analyzed showed antimicrobial properties against the tested microorganisms, presenting better activity against the S. aureus than E. Coli. These findings suggest that LDPE films with silver nanoparticles are promising to provide a significant contribution to the quality and safety of packaged food.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fenômenos Químicos , Embalagem de Alimentos , Nanopartículas Metálicas/química , Polietileno/química , Prata/química , Escherichia coli/efeitos dos fármacos , Dióxido de Silício/química , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Titânio/química
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