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1.
Arch Microbiol ; 205(4): 103, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36867264

RESUMO

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.


Assuntos
Antineoplásicos , Carcinoma , Neuroblastoma , Humanos , Serratia marcescens , Cromatografia Líquida , Espectrometria de Massas em Tandem , Linhagem Celular , Serratia
2.
Opt Express ; 27(5): 7330-7343, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876298

RESUMO

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.

3.
J Invertebr Pathol ; 167: 107249, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31541623

RESUMO

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 (p > 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.


Assuntos
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/ultraestrutura
4.
J Periodontal Res ; 53(4): 636-642, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29704248

RESUMO

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.


Assuntos
Fibroblastos/efeitos dos fármacos , Fibroblastos/ultraestrutura , Gengiva/citologia , Proteínas/farmacologia , Transfecção , Humanos , Microscopia Eletrônica de Transmissão , Coloração e Rotulagem
5.
Opt Express ; 24(17): 19552-7, 2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27557232

RESUMO

The impact of vectorial magnetic field effects on electrical conductivity and nonlinear optical transmittance exhibited by multi-wall carbon nanotubes was studied. The samples were synthetized by an aerosol pyrolysis processing route in a thin film form. Optical signals in a two-wave mixing configuration allowed us to identify two orthogonal directions of propagation for a magnetic field travelling through the nanomaterials studied. A selective modification in optical absorption was considered to be induced by magnetic perturbations in the sample. Standard optical Kerr gate measurements were carried out for exploring the third order nonlinear optical behavior of the film. A capacitive effect influenced by optical and magnetic excitations was distinguished to be characteristic of the sample. Magneto-quantum conductivity sensitive to the direction of an external magnetic field interacting with the tubes was analyzed. Magnetically-induced changes in electronic band parameters seem to be the main responsible for the optical and electrical modulation observed in the nanostructures. Immediate applications for developing magneto-optical and magneto-electrical functions can be contemplated.

6.
BJOG ; 121(6): 739-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24575872

RESUMO

OBJECTIVE: To examine the determinants of a positive visual inspection after acetic acid (VIA), including the relationship of testing positive for high-risk human papillomavirus (HR-HPV), which is the necessary cause of cervical cancer. DESIGN: A prospective cohort study. SETTING: Three clinical sites in rural China. POPULATION: A total of 7541 women aged 25-65 years. METHODS: All women underwent VIA, DNA testing, by two DNA tests performed on both clinician- and self-collected specimens, and HPV E6 oncoprotein testing. Those positive by any test underwent colposcopy and four-quadrant biopsy evaluation. A random sample of women with negative screening results also underwent colposcopy and, if colposcopic abnormalities were observed, four-quadrant biopsy evaluation was performed. Women diagnosed with cervical intraepithelial neoplasia grade 2 (CIN2), or more severe grades (CIN2 + ), underwent treatment. MAIN OUTCOME MEASURE: Testing positive for VIA. RESULTS: Overall, 7.6% (95% confidence interval, 95% CI, 7.0-8.2%) had a positive VIA. Women who tested positive for HPV were more likely to have a positive VIA than women who tested negative for HPV (15.0%, 95% CI 12.9-17.2% versus 6.3%, 95% CI 5.7-6.9%; P < 0.001). Older women were less likely to have a positive VIA (Ptrend  < 0.001), including women with CIN2 +  (Ptrend  < 0.001). A logistic regression model demonstrated that diagnosis (CIN2 +  versus

Assuntos
Ácido Acético , Colposcopia , Detecção Precoce de Câncer , Indicadores e Reagentes , Infecções por Papillomavirus/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , China/epidemiologia , Estudos de Coortes , Colposcopia/métodos , DNA Viral/isolamento & purificação , Detecção Precoce de Câncer/métodos , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/isolamento & purificação , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Infecções por Papillomavirus/mortalidade , Estudos Prospectivos , População Rural , Sensibilidade e Especificidade , Manejo de Espécimes , Neoplasias do Colo do Útero/mortalidade , Esfregaço Vaginal , Displasia do Colo do Útero/mortalidade
7.
Acad Psychiatry ; 38(5): 611-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25224015

RESUMO

OBJECTIVE: This study aims to briefly describe a curriculum on trauma in order to help other educators in their own planning and development of teaching on trauma. METHODS: The 12-week course was offered to third-year psychiatry residents as part of their didactics scheduling. The classes included information on a wide variety of types of trauma including natural disasters, childhood trauma, refugee trauma, survivors of torture, intimate partner violence, and military sexual trauma. The course also offered techniques in therapy informed by transference and countertransference along with role-playing activities with the resident participants. Residents completed a pre- and postcourse survey in order to assess the attitudes, comfort, and knowledge in screening for trauma exposure. RESULTS: The proportion of residents who reported that it was very important to screen for trauma increased. Similarly, the proportion of residents who indicated they now screen for trauma increased as well. However, these were nonsignificant changes. There was no change in the proportion of residents who felt comfortable assessing for trauma before and after the curriculum. Even after the course, almost half of the respondents reported that they were still not comfortable in asking about refugee's experience of trauma or torture CONCLUSIONS: More residents reported that they screen for trauma after the curriculum. An ongoing development and evaluation of model curricula including possible expansion across specialties and health-care disciplines is warranted for this critically important topic area.


Assuntos
Internato e Residência , Psiquiatria/educação , Ferimentos e Lesões/psicologia , Currículo , Humanos , Internato e Residência/métodos
8.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 57-63, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37117133

RESUMO

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 (p = 0.032), as were those of AST (p = 0.011) and ALT (p = 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.

9.
Rehabilitacion (Madr) ; 58(3): 100855, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38795503

RESUMO

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.


Assuntos
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 Especificidade
10.
Microb Pathog ; 61-62: 23-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23651670

RESUMO

Upon oxygen shift-down, Mycobacterium tuberculosis complex bacteria can induce a genetic program characterized by halted duplication, which is called Non-replicating persistence (NRP). During this phase, at least 48 genes, collectively named Dormancy survival regulator (DosR) regulon, are important for the long-term survival of bacilli under a non-respiring state, a condition that bacilli encounter inside granulomatous lesions. It remains unclear whether expression of NRP genes occurs within the tissue of Mycobacterium bovis naturally infected cattle. In order to start dissecting this question, total RNA from bovine lymph node tissues of sacrificed tuberculin reacting animals was isolated and transcription of genes required for in vivo duplication (esxB and fbpB) and in vitro NRP (hspX, pfkB, and mb2660c) were analyzed by RT-PCR approaches. Detection of transcripts was positive in bovine tissue samples for genes hspX, pfkB, and mb2660c in 84, 32, and 21%, respectively. NRP genes were upregulated even in animals with a negative IFN-γ in vitro test, and the expression of NRP genes occurred more often than expression of the esxB gene.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Linfonodos/microbiologia , Mycobacterium bovis/crescimento & desenvolvimento , Regulação para Cima , Animais , Proteínas de Bactérias/genética , Bovinos , Interferon gama/biossíntese , Testes de Liberação de Interferon-gama , Mycobacterium bovis/genética , Mycobacterium bovis/metabolismo , Mycobacterium bovis/patogenicidade , Regulon , Testes Cutâneos , Teste Tuberculínico , Tuberculose Bovina/microbiologia
11.
Nanotechnology ; 24(4): 045201, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23298951

RESUMO

We report the observation of photoconduction and a strong nonlinear optical absorptive response exhibited by multi-wall carbon nanotubes. An aerosol pyrolysis method was employed for the preparation of the samples. Measurements of the optical transmittance with 7 ns pulses at 1064 nm wavelength allowed us to identify a two-photon absorption effect as the main mechanism of third-order nonlinearity. Photoconductive experiments at 445 nm wavelength seem to confirm the possibility for generating non-resonant multi-photonic absorption processes in the multi-wall carbon nanotubes. By the optical control of the conductivity in the nanotubes, we implement an optoelectronic amplitude modulator device with potential applications for sharp selective functionalities.


Assuntos
Eletrodos , Nanotubos de Carbono/química , Nanotubos de Carbono/efeitos da radiação , Fotometria/instrumentação , Refratometria/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Teste de Materiais , Fotometria/métodos , Propriedades de Superfície
12.
Appl Opt ; 52(22): E22-7, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23913083

RESUMO

Electrical and nonlinear optical experiments were performed on multiwall carbon nanotubes (CNTs) prepared by a chemical vapor deposition method. We report that the incorporation of platinum particles on the CNTs surface originates an enhancement in the photoconductive properties with noticeable capabilities to modulate optical and electrical signals. The photoconductive logic gate function OR was experimentally demonstrated using a simple photoconductive platform based on our samples. A two-photon absorption effect was identified as the main mechanism of third-order optical nonlinearity under a nonresonant nanosecond excitation. Multiphotonic interactions were described in order to explain the observed behavior.

13.
Rehabilitacion (Madr) ; 57(3): 100737, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-36357221

RESUMO

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.


Assuntos
COVID-19 , Pessoas com Deficiência , Transtornos Motores , Adulto , Humanos , Feminino , Adolescente , Masculino , Pandemias , Atividades Cotidianas
14.
Artigo em Inglês | MEDLINE | ID: mdl-38116203

RESUMO

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.

15.
Braz J Biol ; 83: e274345, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126631

RESUMO

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.


Assuntos
Rhizobium , Trifolium , Giberelinas/farmacologia , Hidroponia , Ração Animal , Poaceae
16.
Artigo em Inglês | MEDLINE | ID: mdl-35691555

RESUMO

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.


Assuntos
Smegmamorpha , Animais , Perfilação da Expressão Gênica , Temperatura Alta , Smegmamorpha/genética , Smegmamorpha/metabolismo , Temperatura , Transcriptoma
17.
Mar Pollut Bull ; 180: 113738, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35635877

RESUMO

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.


Assuntos
Crassostrea , Poluentes Químicos da Água , Animais , Crassostrea/metabolismo , Hidrocarbonetos/metabolismo , Hidrocarbonetos/toxicidade , Imunidade , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/análise
18.
Rehabilitacion (Madr) ; 55(2): 125-137, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33272607

RESUMO

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.


Assuntos
Traumatismos da Medula Espinal , Cadeiras de Rodas , Adaptação Fisiológica , Humanos , Psicometria , Reprodutibilidade dos Testes
19.
Mar Biotechnol (NY) ; 23(1): 62-76, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33040235

RESUMO

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 (♀) and pink abalone H. corrugata (♂), 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.


Assuntos
Gastrópodes/crescimento & desenvolvimento , Gastrópodes/genética , Hibridização Genética , Animais , Aquicultura , Metabolismo Basal/genética , Calcificação Fisiológica/genética , Feminino , Gastrópodes/metabolismo , Expressão Gênica , Temperatura Alta , Masculino , Transcriptoma
20.
Opt Express ; 18(16): 16406-17, 2010 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-20721027

RESUMO

We use two different synthesis approaches for the preparation of TiO(2) films in order to study their resulting third order optical nonlinearity, and its modification by the inclusion of Au nanoparticles in one of the samples. An ultrasonic spray pyrolysis method was used for preparing a TiO(2) film in which we found two-photon absorption as a dominant nonlinear effect for 532 nm and 26 ps pulses; and a purely electronic nonlinearity at 830 nm for 80 fs pulses. A strong optical Kerr effect and the inhibition of the nonlinear optical absorption in 532 nm can be obtained for the first sample if Au nanoparticles embedded in a second TiO(2) film prepared by a sol-gel technique are added to it. We used an optical Kerr gate, z-scan, a multi-wave mixing experiment and an input-output transmittance experiment for measuring the optical nonlinearities.


Assuntos
Ouro , Nanopartículas Metálicas/química , Modelos Químicos , Fotoquímica/métodos , Fótons , Espalhamento de Radiação , Titânio/química , Absorção , Simulação por Computador , Membranas Artificiais , Dinâmica não Linear
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