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The objective was to perform a systematic review of those performance outcomes (HRD) tools that assess sensitivity in post-stroke subjects, as well as to know which of all is the most reliable and viable. The design was a systematic review. The following were included: HRD, developed in post-stroke subjects, of any etiology and period of evolution; 18 years of age or older and testing for sensitivity; results on psychometric properties. Excluded: self-reported results, the report of cross-cultural adaptation, designed through computerized means. 19 HRD were acquired. The psychometric properties analyzed were reliability, internal consistency, measurement error, construct validity, content validity, and sensitivity to change, the first being the most studied. Psychometric properties were identified, assessed, compared, and summarized. Of all of them, we recommend the use of the modified Erasmus Nottingham Sensory Assessment, as it presents the best degree of confidence in the evidence.
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Psicometria , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/complicações , Reprodutibilidade dos Testes , Avaliação de Resultados em Cuidados de Saúde , Sensibilidade e EspecificidadeRESUMO
INTRODUCTION AND AIM: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged, causing the current pandemic of acute respiratory disease known as COVID-19. Liver injury due to COVID-19 is defined as any liver injury occurring during the course of the disease and treatment of patients with COVID-19, with or without liver disease. The incidence of elevated liver transaminases, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), ranges from 2.5 to 76.3%. The aim of the present study was to describe the hepatic biochemical abnormalities, after a SARS-CoV-2-positive polymerase chain reaction (PCR) test, and the mortality rate in critically ill patients. MATERIALS AND METHODS: A retrospective study was conducted that included 70 patients seen at a private hospital in Mexico City, within the time frame of February-December 2021. Median patient age was 44.5 years (range: 37-57.2) and 43 (61.4%) of the patients were men. Liver function tests were performed on the patients at hospital admission. RESULTS: Gamma glutamyl transferase (GGT) levels were elevated (pâ¯=â¯0.032), as were those of AST (pâ¯=â¯0.011) and ALT (pâ¯=â¯0.021). The patients were stratified into age groups: 18-35, 36-50, and > 50 years of age. The 18 to 35-year-olds had the highest liver enzyme levels and transaminase levels were higher, the younger the patient. Due to the low mortality rate (one patient whose death did not coincide with a hepatic cause), the multivariate analysis showed an R2 association of 0.689, explained by AST, GGT, and C-reactive protein levels. CONCLUSIONS: Despite the increase in transaminases in our study population during the course of COVID-19, there was no increase in mortality. Nevertheless, hospitalized patient progression should be continuously followed.
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The purpose of the present investigation was to determine the effect of rhizobium and gibberellin on the production of hydroponic green forage from red clover (Trifolium pratense L.) variety quiñequeli, four variables were measured: plant height, biomass weight, grass weight and root weight. The treatments were T0: 0%, T1: 10%, T2: 20%, T3: 30% and T4: 40% of Rhizobium before germination and Gibberellin T0: 0g, T1: 2.4g; T2: 3.3g; T3: 4.3 and T4: 5.3g each treatment with 6 repetitions, three applications on days 5, 10, 15 and 20 of growth. Data were analyzed with DCA, ANOVA and DUNCAN's multiple comparisons test; the results obtained were: first measurement with rhizobium without gibberellin there were no statistical differences, second and third measurement with Gibberellin application did not present statistical differences and the fourth measurement presented statistical difference (α=0.05), average height of the plant with a mean of 12.82 cm, T4 was higher, in biomass a statistical difference was obtained with a mean of 3.056 kg, T3 was higher, weight of grass and root did not present statistical differences; concluding that the use of rhizobium and gibberellin could be a usable alternative in the production of hydroponic green fodder, to alleviate the problems of fodder scarcity in dry season, its use being recommended in high Andean livestock.
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Rhizobium , Trifolium , Giberelinas/farmacologia , Hidroponia , Ração Animal , PoaceaeRESUMO
Introduction: As a lifestyle factor, poor sleep status is associated with increased cardiovascular morbidity and mortality and may be influenced by environmental stressors, including air pollution. Methods: To determine whether exposure to air pollution modified cardiovascular effects of sleep disruption, we evaluated the effects of single or repeated (twice/wk for 4 wks) inhalation exposure to eucalyptus wood smoke (ES; 964 µg/m3 for 1 h), a key wildland fire air pollution source, on mild sleep loss in the form of gentle handling in rats. Blood pressure (BP) radiotelemetry and echocardiography were evaluated along with assessments of lung and systemic inflammation, cardiac and hypothalamic gene expression, and heart rate variability (HRV), a measure of cardiac autonomic tone. Results and Discussion: GH alone disrupted sleep, as evidenced by active period-like locomotor activity, and increases in BP, heart rate (HR), and hypothalamic expression of the circadian gene Per2. A single bout of sleep disruption and ES, but neither alone, increased HR and BP as rats transitioned into their active period, a period aligned with a critical early morning window for stroke risk in humans. These responses were immediately preceded by reduced HRV, indicating increased cardiac sympathetic tone. In addition, only sleep disrupted rats exposed to ES had increased HR and BP during the final sleep disruption period. These rats also had increased cardiac output and cardiac expression of genes related to adrenergic function, and regulation of vasoconstriction and systemic blood pressure one day after final ES exposure. There was little evidence of lung or systemic inflammation, except for increases in serum LDL cholesterol and alanine aminotransferase. These results suggest that inhaled air pollution increases sleep perturbation-related cardiovascular risk, potentially in part by increased sympathetic activity.
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It has been reported that cell-free culture broths and some proteins from pigmented and non-pigmented Serratia spp. are cytotoxic towards cancerous and non-cancerous human cell lines. Looking for new molecules toxic against human cancerous cells but harmless towards normal human cells, the aim of this work was (a) to determine whether cell-free broths from the entomopathogenic non-pigmented S. marcescens 81 (Sm81), S. marcescens 89 (Sm89) and S. entomophila (SeMor4.1) presented cytotoxic activity towards human carcinoma cell lines; (b) to identify and purify the associated cytotoxic factor(s) and (c) to evaluate whether the cytotoxic factor(s) was cytotoxic towards non-cancerous human cells. This research was focussed on the observed morphology changes and the proportion of remaining viable cells after incubation in the presence of cell-free culture broths from the Serratia spp isolates to evaluate cytotoxic activity. The results showed that broths from both S. marcescens isolates presented cytotoxic activity and induced cytopathic-like effects on the human neuroblastoma CHP-212 and the breast cancer MDA-MB-231 cells. Slight cytotoxicity was observed in the SeMor4.1 broth. A serralysin-like protein of 50 kDa was identified in Sm81 broth as responsible for cytotoxic activity after purification by ammonium sulphate precipitation and ion-exchange chromatography followed by tandem-mass spectrometry (LC-MS/MS). The serralysin-like protein was toxic against CHP-212 (neuroblastoma), SiHa (human cervical carcinoma) and D-54 (human glioblastoma) cell lines in a dose-dependent manner and showed no cytotoxic activity in primary cultures of normal non-cancerous human keratinocytes and fibroblasts. Therefore, this protein should be evaluated for a potential use as an anticancer agent.
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Antineoplásicos , Carcinoma , Neuroblastoma , Humanos , Serratia marcescens , Cromatografia Líquida , Espectrometria de Massas em Tandem , Linhagem Celular , SerratiaRESUMO
BACKGROUND AND OBJECTIVE: The World Health Organization declared COrona VIrus Disease 19 (COVID-19) a pandemic and recommended social distancing as a preventive measure. This affected all medical-clinical treatments, including those related to the physical rehabilitation process. The objective was to describe the perceptions about the rehabilitation process due to the modifications experienced by people with motor disabilities in a rehabilitation hospital during the COVID-19 pandemic. PATIENTS AND METHODS: Qualitative design. The sample chosen was for convenience and the data analysis was by thematic analysis, which allows to identify, analyze and report themes. The interviews were conducted with patients seen in the physiotherapy división of the hospital. INCLUSION CRITERIA: adults >18 years old, diagnosis of motor disability, undergoing physical treatment ≥1 month on an outpatient basis, with early discharge from hospitalization or hospitalization at the time of the study and signing of the informed consent. EXCLUSION CRITERIA: physical discharge for reasons other than COVID-19 and diagnosis of psychiatric illness. RESULTS: The sample consisted of 16 participants. 31.2% were female. Twelve presented various neurological alterations and 4 amputation effects. Four main themes were identified: importance of rehabilitation, treatment modifications/interruption, activities of daily living and tele-rehabilitation. CONCLUSIONS: Perceptions about the rehabilitation process and the impact on the modifications experienced in people with motor disabilities were described. We highlight the importance of tele-rehabilitation as an alternative resource.
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COVID-19 , Pessoas com Deficiência , Transtornos Motores , Adulto , Humanos , Feminino , Adolescente , Masculino , Pandemias , Atividades CotidianasRESUMO
Introducción: la pandemia por SARS-CoV-2 planteó un desafío para todo el equipo de salud. Fue necesario analizar y pensar en este contexto el rol de enfermería en la atención y cuidados del paciente y su familia. Los procesos asistenciales debieron adaptarse a nuevas y diversas situaciones que generaron la atención de pacientes en su mayoría con comorbilidades asociadas. El objetivo del trabajo fue describir el rol de enfermería y la implementación de diversos protocolos y procesos de atención de pacientes en salas de internación pediátrica del área COVID de un hospital de alta complejidad. Material y métodos: se realizó un estudio retrospectivo y descriptivo sobre el personal de enfermería que participó en la atención de casos sospechosos o confirmados de COVID-19 durante la pandemia y los protocolos implementados para los cuidados de enfermería. Resultados: solo el 52.5% (n 79) del personal tenía experiencia mayor a tres años, el 75% (n: 113) pertenecían al género femenino, el 47% (n: 71) eran licenciados en enfermería. Conclusiones: Los profesionales enfermeros han logrado mediante sus fortalezas disciplinares dar respuesta a las necesidades del paciente pediátrico y su familia frente a la crisis sanitaria. Las competencias desarrolladas en la administración de los recursos disponibles, la adaptación, flexibilidad a los procesos y líneas estratégicas en tiempo real, posicionan al enfermero como un valor fundamental en el cuidado asistencial (AU)
Introduction: The SARS CoV-2 pandemic posed a challenge for the entire healthcare team. It was necessary to analyze and reflect on the role of nursing in the care of patients and their families in this context. Care processes had to be adapted to new and diverse situations that were generated by the care for patients who usually had associated comorbidities. The aim of the study was to describe the nursing role and the implementation of different protocols and processes for patient care in pediatric inpatient wards in the COVID area of a tertiary-care hospital. Material and methods: a retrospective descriptive study was conducted in the nursing personnel involved in the care of suspected or confirmed cases of COVID-19 during the pandemic and the protocols implemented for nursing care. Results: only 52.5% (n: 79) of the personnel had more than three years of experience, 75% (n: 113) were female, and 47% (n: 71) had a nursing degree. Conclusions: Through their disciplinary strengths, nursing professionals have been able to respond to the needs of pediatric patients and their families in the face of the health crisis. The skills developed in the management of available resources, adaptation, and flexibility to processes and real-time strategies, have positioned nurses as a fundamental factor in healthcare (AU)
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Humanos , Adulto , Pessoa de Meia-Idade , Comorbidade , Criança Hospitalizada , Papel do Profissional de Enfermagem , COVID-19/enfermagem , Hospitais Pediátricos , Processo de Enfermagem , Estudos RetrospectivosRESUMO
Hippocampus erectus inhabiting the shallow coastal waters of the southern Gulf of Mexico are naturally exposed to marked temperature variations occurring in different temporal scales. Under such heterogeneous conditions, a series of physiological and biochemical adjustments take place to restore and maintain homeostasis. This study investigated the molecular mechanisms involved in the response of H. erectus to increased temperature using transcriptome analysis based on RNA-Seq technology. Data was obtained from seahorses after 0.5-h exposure to combinations of different target temperatures (26 °C: control, and increased to 30 and 33 °C) and rates of thermal increase (abrupt: < 5 min; gradual: 1-1.5 °C every 3 h). The transcriptome of seahorses was assembled de novo using Trinity software to obtain 29,211 genes and 30,479 transcripts comprising 27,520,965 assembled bases. Seahorse exposure to both 30 and 33 °C triggered characteristic processes of the cellular stress response, regardless of the rate of thermal change. The transcriptomic profiles of H. erectus suggest an arrest of muscle development processes, the activation of heat shock proteins, and a switch to anaerobic metabolism within the first 0.5 h of exposure to target temperatures to ensure energy supply. Interestingly, apoptotic processes involving caspase were activated principally in gradual treatments, suggesting that prolonged exposure to even sublethal temperatures results in the accumulation of deleterious effects that may eventually terminate in cellular death. Results herein validate 30 °C and 33 °C as potential upper limits of thermal tolerance for H. erectus at the southernmost boundary of its geographic distribution.
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Smegmamorpha , Animais , Perfilação da Expressão Gênica , Temperatura Alta , Smegmamorpha/genética , Smegmamorpha/metabolismo , Temperatura , TranscriptomaRESUMO
Crassostrea virginica was exposed to different light crude oil levels to assess the effect on transcriptomic response and metabolic rate. The exposure time was 21 days, and levels of 100 and 200 µg/L were used, including a control. The most significant difference among treatments was the overexpression of several genes associated with energy production, reactive oxygen species (ROS) regulation, immune system response, and inflammatory response. Also, a hydrocarbon concentration-related pattern was identified in ROS regulation, with a gene expression ratio near 1.8:1 between 200 and 100 µg/L treatments. Statistical analysis showed no interaction effect for metabolic rate; however, significant differences were found for oil concentration and time factors, with a higher oxygen consumption at 200 µg/L. Our findings provide novel information about the metabolic response of C. virginica during hydrocarbons exposure. In addition, our results point out which biological processes should be investigated as targets for searching bioindicators.
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Crassostrea , Poluentes Químicos da Água , Animais , Crassostrea/metabolismo , Hidrocarbonetos/metabolismo , Hidrocarbonetos/toxicidade , Imunidade , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/análiseRESUMO
Along the Pacific coast of the Baja California Peninsula (Mexico), abalone represents one of the most lucrative fisheries. As wild populations are currently depleted, abalone farm production aims to balance the decreasing populations with the increasing demand. The Mexican abalone aquaculture is almost entirely based on red abalone (Haliotis rufescens). However, the increasing frequency of extreme temperature events is hampering this activity. The use interspecific hybrids can potentially improve abalone culture, as species have differences in their thermal tolerance. Therefore, the hybrid progeny between H. rufescens (â) and pink abalone H. corrugata (â), a temperate and a warmer water abalone species, respectively, will naturally support higher temperature. To test this hypothesis, growth rate, mortality and metabolic rate of both pure (RR) and hybrid abalone (RP) were assessed under the H. rufescens' optimum (18 °C) and thermally stressed (22 °C) conditions. To unveil the molecular pathways involved in the heat response, transcriptional profiling of both crosses was also investigated. At high temperature, we observed constrained growth and survival in RR while RP showed a significant increase in both rates, supporting the improved performance of the hybrid compared. These results match with the transcriptional profiling of hybrids showing higher expression of genes involved in growth and calcification, whereas in the pure red progeny, the transcriptional profile was mainly associated with the regulation of necroptosis process. Our results may contribute to propose new management plans to increase farm abalone production in Baja California.
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Gastrópodes/crescimento & desenvolvimento , Gastrópodes/genética , Hibridização Genética , Animais , Aquicultura , Metabolismo Basal/genética , Calcificação Fisiológica/genética , Feminino , Gastrópodes/metabolismo , Expressão Gênica , Temperatura Alta , Masculino , TranscriptomaRESUMO
A total of 60% of people with a spinal cord injury are completely dependent on a wheelchair. There is a wide variety of instruments that assess wheelchair skills, but they are not specific for this population. OBJECTIVE: To identify, assess, compare and summarize the psychometric properties of instruments that assess wheelchair skills in persons with a spinal cord injury. A systematic review was conducted and observational instruments were included that assessed wheelchair skills in persons with spinal cord injury. Eleven articles were identified that evaluated eight instruments. Most of them reported activities according to the International Classification of Functioning, Disability and Health. Reliability was the most frequently evaluated psychometric property. The Queensland Evaluation of Wheelchair Skills and the Adapted Manual Wheelchair Circuit had the best degrees of confidence in the evidence, and their application could guide the selection of pertinent therapeutic strategies. PROSPERO registration: CRD42020161430.
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Traumatismos da Medula Espinal , Cadeiras de Rodas , Adaptação Fisiológica , Humanos , Psicometria , Reprodutibilidade dos TestesRESUMO
RESUMEN La poroqueratosis es un trastorno de la queratinización, con herencia autosómica dominante en la mayoría de los casos, vinculada posiblemente a la presencia de un clon mutante de queratinocitos en expansión. Tiene diferentes formas clínicas: de Mibelli, actínica superficial diseminada, lineal, puntiforme, palmoplantar y facial atípica. El diagnóstico se confirma con la histología, presentándose típicamente la laminilla cornoide, que no es patognomónica de esta afección. En el tratamiento de esta patología se utilizan desde agentes tópicos como emolientes, 5-fluorouracilo, calcipotriol, imiquimod y retinoides como terapia sistémica. Otras opciones terapéuticas descritas son extirpación quirúrgica, criocirugía y dermoabrasión cuando se trata de formas localizadas o únicas. Se decide reportar el caso de una paciente femenina con poroqueratosis de afección exclusiva del área nasal por su rara frecuencia y escasos reportes sobre esta forma de presentación en la actualidad.
ABSTRACT Porokeratosis is a disorder of keratinization, with AD inheritance in most cases; possibly linked to the presence of a mutant clone of expanding keratinocytes, in addition to the overexpression of the p53 gene that could be related to an oncogenic potential. This disorder has also been associated with factors such as UVR, immunosuppression cases such as HIV +, liver or kidney failure, transplantation of organs that would act as triggers of this disease. It differs from other pathologies due to the presence of a peripheral hyperkeratotic ring which is usually asymptomatic in half of the patients. Clinically it can occur in different ways: porokeratosis de Mibelli, superficial actinic disseminated, linear, punctate, palmoplantar and atypical facial. Diagnosis is confirmed with histology, with the cornoid lamella typically present, which is not pathognomonic of this condition and consists of a parakeratotic keratinocyte column that extends from an invagination of the epidermis through the stratum corneum. The treatment to choose, will depend on the patient´s age; Size and location of the lesions, the aesthetic implications and the general condition of the affected person. They are used from topics such as emollients, 5-fluorouracil, calcipotriol, imiquimod. Retinoids are found as an option for systemic therapy. Another procedure considers surgical removal, cryosurgery and dermabrasion when dealing with localized or unique forms. We report a case of a 44-year-old female patient who presents with compatible dermatosis porokeratosis, affecting only the nasal area.
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INTRODUCTION: Anterolateral transpsoas approach is considered as safe access to the retroperitoneum with low risk of complications. The most frequent described complications due to this approach were nerve, bowel, urethral and kidney injury. An incisional hernia is a rare complication in anterolateral approach, as a result of a nonhealing surgical wound or late disruption of the fascia; it occurs in 1% of the incisions after primary closure. CASE DESCRIPTION: We report a 75-year-old woman who underwent spinal surgery with a double approach, consisting of an anterolateral transpsoas approach and posterior lumbar approach. Two months post-surgery, the patient developed a lateral abdominal tumor at the surgical site. CONCLUSION: To prevent incisional hernia, a meticulous dissection must be performed to avoid muscle denervation and weakening of the abdominal wall, as well as proper repair of the fascia its critical to ensure an adequate closure of the wound.
INTRODUCCIÓN: El Abordaje anterolateral transpsoas se considera como un acceso seguro al retroperitoneo con bajo riesgo de complicaciones. Las complicaciones descritas más frecuentes debido a este abordaje fueron lesiones nerviosas, intestinales, uretrales y renales. Una hernia incisional es una complicación poco frecuente en el abordaje anterolateral, como resultado de una herida quirúrgica no cicatrizada o una ruptura tardía de la fascia; ocurre en 1% de las incisiones después del cierre primario. CASO CLÍNICO: Informamos de una mujer de 75 años que se sometió a una cirugía de columna vertebral con un doble abordaje quirúrgico, que consiste en un abordaje anterolateral transpsoas y un abordaje lumbar posterior. Dos meses después de la cirugía, el paciente desarrolló un tumor abdominal lateral en el sitio quirúrgico. CONCLUSIÓN: Para prevenir la hernia incisional, se debe realizar una disección meticulosa para evitar la denervación muscular y el debilitamiento de la pared abdominal, así como la correcta reparación de la fascia es crítico para asegurar un cierre adecuado de la herida.
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Hérnia Incisional , Idoso , Feminino , Humanos , Hérnia Incisional/etiologia , Hérnia Incisional/cirurgia , Complicações Pós-Operatórias/etiologiaRESUMO
Introduction: Tuberculosis (TB) is one of the most prevalent infectious diseases in the world. Current vaccination with BCG can prevent meningeal and disseminated TB in children. However, success against latent pulmonary TB infection (LTBI) or its reactivation is limited. Evidence suggests that there may be means to improve the efficacy of BCG raising the possibility of developing new vaccine candidates against LTBI.Areas covered: BCG improvements include the use of purified mycobacterial immunogenic proteins, either from an active or dormant state, as well as expressing those proteins from recombinant BCG strains that harvor those specific genes. It also includes boost protein mixtures with synthetic adjuvants or within liposomes, as a way to increase a protective immune response during chronic TB produced in laboratory animal models. References cited were chosen from PubMed searches.Expertopinion: Strategies aiming to improve or boost BCG have been receiving increased attention. With the advent of -omics, it has been possible to dissect several specific stages during mycobacterial infection. Recent experimental models of disease, diagnostic and immunological data obtained from individual M. tuberculosis antigens could introduce promising developments for more effective TB vaccines that may contribute to eliminating the hidden (latent) form of this infectious disease.
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Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Erradicação de Doenças , Desenvolvimento de Medicamentos/métodos , Mycobacterium tuberculosis/imunologia , Tuberculose/prevenção & controle , HumanosRESUMO
We describe a nematode infestation of the Atrina maura, the most valuable pen shell fished in Mexico, for the first time. Observations by Mexican authorities indicated that parasites were found encysted in pen shell gonads. The aims of this study included: (i) to identify the parasite morphologically; (ii) to quantify the infestation in different tissues of the pen shell; and (iii) to establish the seasonal variation in gonadal development. During 2015, 10 to 40 pen shells were randomly collected each month from the same commercial bed, and gonads were preserved and processed histologically to establish the seasonal and monthly frequency of infested gonads. A subsample of 35 pen shells was used to identify the parasite and to characterize the infestation of the muscle, mantle, gonad, and digestive gland tissue components. All tissues were dissected, and parasites were collected, photographed, quantified, and adequately preserved for species identification using scanning electron microscopy. Prevalence, intensity of infestation, abundance and crowding data were analyzed by Quantitative Parasitology software and compared monthly and seasonally using a chi test and analysis of means. Results indicated that all parasites were juvenile (second stage) nematodes, Echinocephalus pseudouncinatus. Parasites were found only in muscle and gonad tissues in both male and female pen shells. Hyperpigmentation was observed in the muscle and atretic oocytes with phagocytosis in the gonads. The frequency of infested gonads was significantly higher during winter but was not related to shell size or sex (pâ¯>â¯0.05). A greater number of pen shells were observed to be infested during December and August and during pen shell spawning and development stages. The highest frequency of infested gonads (40%) occurred in December when the lowest temperature and chlorophyll a concentration were recorded. The effects of the biotic and abiotic parameters on this host-pathogen relationship need further research. This nematode species is related to species that are causal agents of gnathostomiasis, which may constitute a health hazard for raw muscle consumers and could affect the reproductive activity of pen shell.
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Bivalves/parasitologia , Infecções por Spirurida , Spirurina/isolamento & purificação , Animais , Gônadas/parasitologia , México , Músculos/parasitologia , Alimentos Marinhos/parasitologia , Estações do Ano , Infecções por Spirurida/diagnóstico , Infecções por Spirurida/patologia , Spirurina/ultraestruturaRESUMO
Nanoscale plasmonic particles represent a crucial transformation on optical and electronic properties exhibited by advanced materials. Herein are reported remarkable interferometric optical effects with dependence on polarization for filtering or modulating electronic signals in multilayer nanostructures. Metallic nanoparticles were incorporated in randomly distributed networks of reduced graphene oxide by an in-situ vapor-phase deposition method. The polarization-selectable nonlinear optical absorption contribution on the photoconductivity of reduced graphene oxide decorated with gold nanoparticles was analyzed. Nanosecond pulses at 532 nm wavelength were employed in a two-wave mixing experiment to study photoconduction and nonlinear optical absorption in this nanohybrid material. The ablation threshold of the sample was measured in 0.4 J/cm2. Electrochemical impedance spectroscopy measurements revealed a capacitive response that can be enhanced by gold decoration in carbon nanostructures. A strong two-photon absorption process characterized by 5 × 10-7 m/W was identified as a physical mechanism responsible for the nonlinear photoconductive behavior of the nanostructures. Experimental shift of 1 MHz for the cutoff frequency associated with an electrical filter function performed by the sample in film form was demonstrated. Moreover, amplitude modulation of electronic signals controlled by the polarization of a two-wave mixing experiment was proposed. All-optical and optoelectronic nanosystems controlled by multi-photonic interactions in carbon-based materials were discussed. The key role of the vectorial nature of light in two-wave mixing experiments is a fascinating tool for the exploration of low-dimensional systems.
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Biomarcadores/análise , Vacinas contra a Tuberculose/administração & dosagem , Tuberculose/prevenção & controle , Imunidade Adaptativa , Humanos , Tuberculose Latente/imunologia , Tuberculose Latente/prevenção & controle , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Vacinas contra a Tuberculose/imunologia , VacinaçãoRESUMO
Removal of hexavalent chromium was accomplished by using photocatalyst materials of TiO2 doped with tungsten oxide, environmental air as oxygen supply and white light as irradiation source. Dichromate anions in concentration ranges of 50 to 1000⯵g/L were removed by means of aqueous dispersions of TiO2 doped with tungsten. The aqueous chromium analyses were performed by Differential Pulse Voltammetry technique. Additionally, mineralization of CO2 gas was promoted by the photocatalysis process, as was clearly shown by Raman spectroscopy and X-ray Photoelectron Spectroscopy (XPS) analyses obtained from the TiO2 samples recovered after photocatalytic experiments. Results of sample analyses by Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) are presented and discussed.
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BACKGROUND AND OBJECTIVE: Transfection of cementum protein 1 (CEMP1) into human gingival fibroblasts (HGFs) notably increases cell metabolism and results in overexpression of molecules related to biomineralization at transcriptional and protein levels. Therefore, HGF-CEMP1 cells are considered as putative cementoblasts. This represents a significant advance in periodontal research because cementum neoformation is a key event in periodontal regeneration. In addition, it is well known that important changes in cell metabolism and protein expression are related to nucleolar structure and the function of this organelle, which is implicated in ribosome biogenesis. The aim of this study was to determine the effect of transfecting CEMP1 gene in human HGF on the ultrastructure of the nucleolus. MATERIAL AND METHODS: Cells were processed using the conventional technique for transmission electron microscopy, fixed with glutaraldehyde, postfixed with osmium tetraoxide, and embedded in epoxy resin. Semi-thin sections were stained with Toluidine blue and observed by light microscopy. Thin sections were stained with uranyl acetate and lead citrate. For ribonucleoprotein detection, the staining method based on the regressive effect of EDTA was used. In addition, the osmium ammine technique was used for specific staining of DNA. RESULTS: The results obtained in this study suggest that transfection of CEMP1 into HGFs does not produce changes in the general nucleolar ultrastructure because the different components of the organelle are present as fibrillary centers, and dense fibrillar and granular components compared with the control. CONCLUSION: The transfection of CEMP1 into HGFs allows these cells to perform cementoblast-like functions without alteration of the ultrastructure of the nucleolus, evaluated by the presence of the different compartments of this organelle involved in ribosomal biogenesis.
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Fibroblastos/efeitos dos fármacos , Fibroblastos/ultraestrutura , Gengiva/citologia , Proteínas/farmacologia , Transfecção , Humanos , Microscopia Eletrônica de Transmissão , Coloração e RotulagemRESUMO
In the present work, we report on the synthesis of peptide functionalized magneto-plasmonic nanoparticles in a simple microfluidic platform. Superparamagnetic nanoparticles and gold nanorods were selected for this study. Magnetic nanoparticles were functionalized with peptide D1, which can bind selectively to toxic aggregates of the ß-amyloid peptide associated with Alzheimer's disease. Gold nanorods were functionalized with chitosan replacing the surfactant cetyltrimethylammonium bromide to reduce the cytotoxic effect. The selected microfluidic strategy yields structures with plasmonic and magnetic properties in a nanostructure. Cytotoxic assays with SH-SY5Y cells demonstrate that nanoparticles obtained by microfluidics do not affect cell viability at the studied concentrations. Additionally, these magneto-plasmonic nanoparticles inhibit fibril formation demonstrating that the magneto-plasmonic nanoparticles obtained by microfluidics could be applied for a potential treatment and diagnosis of Alzheimer's disease.