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1.
J Dairy Sci ; 107(6): 3899-3915, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38216037

RESUMO

Acidogenic boluses can mitigate potential negative effects of high milk yield at dry-off on udder health. This randomized controlled trial aimed to investigate the effect of administering acidogenic boluses at dry-off on dry period intramammary infection (IMI) dynamics and on milk production parameters, somatic cell count linear score (LSCC), clinical mastitis (CM), and herd removal in the next lactation. A total of 901 cows from 3 dairy farms were randomly allocated to a control (CON, n = 458; no administration of acidogenic boluses at dry-off) or treatment group (TRT, n = 443; administration of 2 acidogenic boluses at dry-off). Quarter milk samples were collected at dry-off and after calving and submitted for bacteriological milk culture. The effects of treatment on the presence of quarter-level postpartum IMI, cure of existing IMI, and acquisition of new IMI, and on the prevalence of cow-level high LSCC (LSCC ≥4) in the first 30 days in milk (DIM) were analyzed using mixed effects logistic regression. Mixed linear regression was used to analyze cow-level milk production parameters (i.e., milk yield, fat corrected milk, fat and protein yield, and LSCC) in the first 90 DIM and until 300 DIM. For CM and herd removal, Cox proportional hazard regression models were used. In addition to treatment group, lactation group at dry-off, presence of high LSCC in the last test-day, average milk yield in the week before dry-off, presence of CM in the lactation of enrollment, and biologically relevant interactions were offered in all models. There was no evidence of a difference in IMI dynamics or in milk, fat corrected milk, protein or fat yields in the subsequent lactation between groups. The TRT group had a lower LSCC in the first 2 mo postpartum compared with the CON group (2.58 ± 0.3 vs. 2.92 ± 0.3 and 2.42 ± 0.3 vs. 2.81 ± 0.3, for first and second month postpartum). The prevalence of high LSCC in the first 30 DIM was 9.1% lower in the TRT compared with the CON group (16.3% vs. 25.5%; risk difference: -9.2; 95% confidence interval [CI]: -15.8, -2.5). Cows in the TRT group exhibited reduced hazards of CM in the subsequent lactation compared with cows in the CON group (hazard ratio: 0.75; 95% CI: 0.63, 0.89) as well as a reduced hazard of herd removal (hazard ratio: 0.82, 95% CI: 0.77, 0.88). The administration of acidogenic boluses as a component of dry-off management is a promising approach to maintain good udder health and reduce the hazard of CM and herd removal during the subsequent lactation.


Assuntos
Lactação , Glândulas Mamárias Animais , Mastite Bovina , Leite , Animais , Bovinos , Feminino , Contagem de Células/veterinária
2.
Opt Express ; 30(21): 37536-37553, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258341

RESUMO

Subaquatic indirect Laser-Induced Plasma-Assisted Ablation (SLIPAA) is proposed as a laser-based technique for glass processing. In this configuration, a water layer is added between a metallic target and a soda-lime glass substrate, so the processing of the glass is due to a combination of the ablation mechanism, the shock waves, and the cavitation bubbles. Thus, this method makes it possible to produce higher depth structures than those performed up to now by other standard laser techniques based on ablation, achieving structures in glass with rectangular cross-sectional profiles. Channels of 1 mm width are fabricated, reaching an average maximal depth value of almost 1400 µm at 30 passes of the laser beam while keeping the focal position fixed. Furthermore, the difference between processing the material with and without the addition of the water layer is presented. The influence of the processing parameters on the shape and quality of the fabricated structures is studied by optical and confocal microscopy, microcomputed tomography, and scanning electron microscopy. Compositional analysis of the glass is performed by energy dispersive X-ray technique to assess the transference of material from the metallic target to the fabricated channels. Deeper and more complex structures are obtained by refocusing the laser beam on the target and adding a pulsed flowing water film.

3.
Int J Environ Health Res ; 32(10): 2271-2285, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34348544

RESUMO

Mycotoxins have several toxicological implications. In the present study, we evaluate the presence of aflatoxin B1 (AFB1), ochratoxin A (OTA), and fumonisin (FB1) in paddy rice, polished rice, and maize from the fields and markets in Nayarit State (Mexico). The results indicated the presence of AFB1 in 21.21% of paddy rice samples and 11.11% of market maize samples. OTA was present in only 3.03% (one sample) of paddy rice samples. FB1 was detected in 87.50% and 88.88% of maize samples from field and market, respectively. The estimated human exposure was calculated for FB1 using the probable daily intake (PDI), which suggested that FB1 could contribute to the development of diseases through the consumption of contaminated maize. Positive samples indicated that some rice and maize samples were not suitable for human consumption. Further efforts are needed to continue monitoring mycotoxins and update national legislation on mycotoxins accordingly.


Assuntos
Fumonisinas , Micotoxinas , Oryza , Aflatoxina B1/análise , Grão Comestível/química , Contaminação de Alimentos/análise , Fumonisinas/análise , Humanos , México , Micotoxinas/análise , Zea mays
4.
Opt Express ; 29(13): 19566-19585, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34266065

RESUMO

In this work, a Monte Carlo ray-tracing model for the simulation and optimization of a fiber Luminescent Solar Concentrator (LSC) based on stacked layers of fiber arrays is developed and validated. The fiber LSC efficiency improvements are compared against a conventional planar LSC. We developed a new model to analyze the performance of different configurations of bulk-doped fibers and fibers constituted by a doped coating and a passive core. These configurations are analyzed also varying fiber packing geometry diameters, and length. Due to the exceptionally low absorption coefficient of the silica fibers (αwg ≈ 10-4 cm-1), concentration factors of up to 1.9 are predicted when dimensions are scaled over 1 m2, which improve more than twice the maximum concentration factor ever reported. These results serve as a preliminary theoretical study for the future development of a new LSC design based on flexible silica micro-fibers coated with Si-QDs doped poly(lauryl methacrylate) (PLMA) layers.

5.
Horm Behav ; 127: 104875, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069753

RESUMO

Oxytocin (OXT) modulates social interactions, attenuates stressful responses and can decrease drug-seeking and taking behaviors. In previous studies, we observed that social defeat (SD) induced a long-lasting increase in ethanol intake and neuroinflammation in male mice. We also know that OXT blocks the increase in cocaine reward induced by SD. Therefore, in the present study we aimed to evaluate the effect of 1 mg/kg of OXT administered 30 min before each episode of SD on ethanol consumption and the neuroinflammatory response in adult male mice. Three weeks after the last SD, mice underwent oral ethanol self-administration (SA) procedure, and striatal levels of the two chemokines CX3CL1 and CXCL12 were measured after the last SD and at the end of the ethanol SA. OXT administration blocked the increase in voluntary ethanol consumption observed in defeated mice, although it did not affect motivation for ethanol. An increase in the striatal levels of CX3CL1 and CXCL12 was observed in defeated animals immediately after the last defeat and after the ethanol SA. However, defeated mice treated with OXT did not show this increase in the neuroinflammatory response. In conclusion, OXT treatment can be a powerful therapeutic target to reduce the negative effects of social stress on ethanol consumption and the neuroinflammatory process.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Neurite (Inflamação)/prevenção & controle , Ocitocina/farmacologia , Derrota Social , Consumo de Bebidas Alcoólicas/metabolismo , Consumo de Bebidas Alcoólicas/psicologia , Animais , Quimiocina CX3CL1/metabolismo , Quimiocina CXCL12/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Etanol/administração & dosagem , Etanol/farmacologia , Masculino , Camundongos , Motivação/efeitos dos fármacos , Neurite (Inflamação)/etiologia , Neurite (Inflamação)/metabolismo , Ocitocina/uso terapêutico , Recompensa , Autoadministração , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia
6.
Nanotechnology ; 32(41)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285145

RESUMO

This study focuses on the development of a new hybrid biological material to be applied in the production of electrical energy. These organo-metallic cells are constituted by cyanobacteria (Fischerella muscicola) and silver nanoparticles (AgNPs). AgNPs were obtained by green synthesis using the extract of the fruit of theBerberis halliiplant as reducing agent with two different concentrations of silver nitrate (AgNO3), 1 and 10 mM. The morphology, physicochemical and electrical properties of the cyanobacteria with and without AgNPs were evaluated. To verify the efficacy of this new material, and the effect of the medium used, Nitrofoska or BG-11, the growth kinetics was evaluated by UV-vis up tot= 63 d with and without renewal of the culture medium and O2/CO2exchange. Through morphological characterizations ofFischerella muscicolait was possible to identify the presence of an associated bacterium identified using molecular techniques asPseudomona guguanensithat could act as a supporting organism in the growth of this cyanobacteria. The studies carried out did not shown cell toxicity for the cultures that have AgNPs and on the other hand, it was observed that the hybrid cells (Cy-AgNPs) are electron carriers recording an increase of up to 57% and 18% in their electrical potential with BG-11 and Nitrofoska culture media, respectively and an increase in the anodic current peak of 6.5% of Cy-AgNPs respect to onlyF. musicola.

7.
BMC Public Health ; 21(1): 1404, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271884

RESUMO

BACKGROUND: BPaL, a 6 month oral regimen composed of bedaquiline, pretomanid, and linezolid for treating extensively drug-resistant tuberculosis (XDR-TB) is a potential alternative for at least 20 months of individualized treatment regimens (ITR). The ITR has low tolerability, treatment adherence, and success rates, and hence to limit patient burden, loss to follow-up and the emergence of resistance it is essential to implement new DR-TB regimens. The objective of this study was to assess the acceptability, feasibility, and likelihood of implementing BPaL in Indonesia, Kyrgyzstan, and Nigeria. METHODS: We conducted a concurrent mixed-methods study among a cross-section of health care workers, programmatic and laboratory stakeholders between May 2018 and May 2019. We conducted semi-structured interviews and focus group discussions to assess perceptions on acceptability and feasibility of implementing BPaL. We determined the proportions of a recoded 3-point Likert scale (acceptable; neutral; unacceptable), as well as the overall likelihood of implementing BPaL (likely; neutral; unlikely) that participants graded per regimen, pre-defined aspect and country. We analysed the qualitative results using a deductive framework analysis. RESULTS: In total 188 stakeholders participated in this study: 63 from Kyrgyzstan, 51 from Indonesia, and 74 from Nigeria The majority were health care workers (110). Overall, 88% (146/166) of the stakeholders would likely implement BPaL once available. Overall acceptability for BPaL was high, especially patient friendliness was often rated as acceptable (93%, 124/133). In contrast, patient friendliness of the ITR was rated as acceptable by 45%. Stakeholders appreciated that BPaL would reduce workload and financial burden on the health care system. However, several stakeholders expressed concerns regarding BPaL safety (monitoring), long-term efficacy, and national regulatory requirements regarding introduction of the regimen. Stakeholders stressed the importance of addressing current health systems constraints as well, especially in treatment and safety monitoring systems. CONCLUSIONS: Acceptability and feasibility of the BPaL regimen is high among TB stakeholders in Indonesia, Kyrgyzstan, and Nigeria. The majority is willing to start using BPaL as the standard of care for eligible patients despite country-specific health system constraints.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/uso terapêutico , Estudos de Viabilidade , Humanos , Indonésia , Quirguistão , Nigéria , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
8.
Ann Oncol ; 31(6): 780-788, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32240793

RESUMO

BACKGROUND: Bromodomain and extra-terminal (BET) proteins are epigenetic readers that regulate expression of genes involved in oncogenesis. CC-90010 is a novel, oral, reversible, small-molecule BET inhibitor. PATIENTS AND METHODS: CC-90010-ST-001 (NCT03220347; 2015-004371-79) is a phase I dose-escalation and expansion study of CC-90010 in patients with advanced or unresectable solid tumors and relapsed/refractory (R/R) non-Hodgkin's lymphoma (NHL). We report results from the dose escalation phase, which explored 11 dose levels and four dosing schedules, two weekly (2 days on/5 days off; 3 days on/4 days off), one biweekly (3 days on/11 days off), and one monthly (4 days on/24 days off). The primary objectives were to determine the safety, maximum tolerated dose (MTD) and/or recommended phase II dose (RP2D) and schedule. Secondary objectives were to evaluate signals of early antitumor activity, pharmacokinetics, and pharmacodynamics. RESULTS: This study enrolled 69 patients, 67 with solid tumors and two with diffuse large B-cell lymphoma (DLBCL). The median age was 57 years (range, 21-80) and the median number of prior regimens was four (range, 1-9). Treatment-related adverse events (TRAEs) were mostly mild and manageable; grade 3/4 TRAEs reported in more than two patients were thrombocytopenia (13%), anemia, and fatigue (4% each). Six patients had dose-limiting toxicities. MTDs were 15 mg (2 days on/5 days off), 30 mg (3 days on/11 days off), and 45 mg (4 days on/24 days off). The RP2D and schedule selected for expansion was 45 mg (4 days on/24 days off). As of 8 October 2019, one patient with grade 2 astrocytoma achieved a complete response, one patient with endometrial carcinoma had a partial response, and six patients had prolonged stable disease ≥11 months. CONCLUSIONS: CC-90010 is well tolerated, with single-agent activity in patients with heavily pretreated, advanced solid tumors.


Assuntos
Antineoplásicos , Linfoma Difuso de Grandes Células B , Linfoma não Hodgkin , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Dose Máxima Tolerável , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto Jovem
9.
Cerebellum ; 19(4): 501-509, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32270466

RESUMO

SCA36 is an autosomal dominant spinocerebellar ataxia (SCA) affecting many families from Costa da Morte, a northwestern region of Spain. It is caused by an intronic GGCCTG repeat expansion in NOP56. In order to characterize the cognitive and affective manifestations of this cerebellar disease, a group of 30 SCA36 mutation carriers (11 preataxic and 19 ataxic patients) were assessed with a comprehensive battery of standardized tests. Phonological verbal fluency - but not semantic fluency - was already mildly impaired in preataxic subjects. In ataxic patients, both phonological and semantic fluencies were significantly below normal. Depression, while more frequent and prominent in ataxic patients, was also often present in the preataxic stage. This is the first systematic study supporting the presence of a mild cerebellar cognitive and affective syndrome in SCA36. Routine evaluation of cognitive and emotional spheres in SCA36 patients as well as asymptomatic mutation carriers should allow early detection and timely therapeutic intervention.


Assuntos
Doenças Cerebelares/genética , Transtornos Cognitivos/genética , Transtornos do Humor/genética , Ataxias Espinocerebelares/complicações , Adulto , Idoso , Doenças Cerebelares/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares , Ataxias Espinocerebelares/patologia , Ataxias Espinocerebelares/psicologia
10.
Parasitology ; 147(7): 791-798, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32127076

RESUMO

The control of gastrointestinal nematodes among ruminants maintained in zoological parks remains difficult due to infective stages develop in the soil. For the purpose to improve the possibilities of the control of gastrointestinal nematodes (genera Trichostrongylus, Nematodirus, Chabertia and Haemonchus) affecting wild captive bovidae ruminants belonging to the subfamilies Antilopinae, Caprinae, Bovinae and Reduncinae, commercial pelleted feed enriched with a blend of 104-105 spores of both filamentous fungi Mucor circinelloides + Duddingtonia flagrans per kg meal was provided for a period of 3.5 years. All animals were dewormed at the beginning of the trial and also when exceeding a cut-off point of 300 eggs per gram of feces (EPG). The anthelmintic efficacy ranged between 96 and 100%. The need for repeating the administration of parasiticide treatment disappeared at the 24th month of study in the Antilopinae individuals, and at the 8th month in the Caprinae, Bovinae and Reduncinae. No side-effects were observed on the skin or in the digestive, respiratory or reproductive system. It was concluded that this strategy provides a sustainable tool for preventing the contamination of paddocks where captive ruminants are maintained, decreasing the risk of infection by gastrointestinal nematodes and consequently the need of frequent deworming.


Assuntos
Ascomicetos/química , Agentes de Controle Biológico/uso terapêutico , Enteropatias/veterinária , Mucor/química , Infecções por Nematoides/veterinária , Ruminantes , Microbiologia do Solo , Animais , Animais Selvagens , Animais de Zoológico , Enteropatias/parasitologia , Enteropatias/prevenção & controle , Infecções por Nematoides/parasitologia , Infecções por Nematoides/prevenção & controle
11.
Am J Transplant ; 18(1): 197-206, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28649744

RESUMO

Mannose-binding lectin (MBL) is synthesized by the liver and binds to microbes. MBL2 gene polymorphisms produce intermediate/low/null or normal MBL serum levels (MBL-deficient or MBL-sufficient phenotypes, respectively). We aimed to evaluate the incidence and severity of infection, rejection, and survival within 1 year after liver transplantation (LT) according to donor and recipient MBL2 gene polymorphisms. A repeated-event analysis for infection episodes (negative binomial regression, Andersen-Gill model) was performed in 240 LTs. Four hundred twenty-eight infectious episodes (310 bacterial, 15 fungal, 65 cytomegalovirus [CMV]-related, and 38 viral non-CMV-related episodes) and 48 rejection episodes were recorded. The main bacterial infections were urinary (n = 82, 26%) and pneumonia (n = 69, 22%). LT recipients of MBL-deficient livers had a higher risk of bacterial infection (incidence rate ratio [IRR] 1.48 [95% confidence interval 1.04-2.09], p = 0.028), pneumonia (IRR 2.4 [95% confidence interval 1.33-4.33], p = 0.013), and septic shock (IRR 5.62 [95% confidence interval 1.92-16.4], p = 0.002) compared with recipients of MBL-deficient livers. The 1-year bacterial infection-related mortality was higher in recipients of MBL-deficient versus MBL-sufficient livers (65.8% vs. 56.1%, respectively; p = 0.0097). The incidence of rejection, viral, or fungal infection was similar in both groups. Recipient MBL2 genotype did not significantly increase the risk of bacterial infection. LT recipients of MBL-deficient livers have a higher risk of bacterial infection, pneumonia, septic shock, and 1-year bacterial infection-related mortality after LT.


Assuntos
Infecções Bacterianas/mortalidade , Rejeição de Enxerto/mortalidade , Transplante de Fígado/mortalidade , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Complicações Pós-Operatórias , Doadores de Tecidos , Adulto , Idoso , Infecções Bacterianas/etiologia , Infecções Bacterianas/patologia , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Lectina de Ligação a Manose/deficiência , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida
12.
Nanotechnology ; 29(32): 325601, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29761791

RESUMO

Carbon nano-onions (CNOs), in their spherical or polyhedral forms, represent an important class of nanomaterials, due to their peculiar physical and electrochemical properties. Among the different methods of production, arc discharge between graphite electrodes sustained by deionized water is one of the most promising to obtain good quality CNOs in gram quantities. We applied the method with the aim to optimize the production of CNOs, using an innovative experimental arrangement. The discharges generate dispersed nanomaterials and a black hard cathodic deposit, which were studied by transmission electron microscopy-high-resolution TEM, scanning electron microscopy, Raman, thermogravimetric analysis and energy-dispersive x-ray spectroscopy. A simple mechanical grinding of the deposits permitted us to obtain turbostratic polyhedral CNOs that exhibited higher stability towards burning in air, compared to CNOs found in water. We propose a mechanism for the formation of the CNOs present in the deposit, in which the crystallization is driven by a strong temperature gradient existing close to the cathode surface at the beginning of the process, and subsequently close to the deposit surface whenever it is growing.

13.
Acta Neurol Scand ; 138(5): 388-393, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29963693

RESUMO

OBJECTIVE: we aimed to evaluate the utility of transorbital ultrasonography (TOS) in optic nerve assessment and quantification of ON atrophy in MS patients, and to determine whether ON atrophy correlates with the disease duration and disability measured on the Kurtzke Expanded Disability Status Scale (EDSS). MATERIALS AND METHODS: Prospective, multicentre, blinded cohort study of 59 patients diagnosed with relapsing-remitting MS and 36 controls. RESULTS: When measured with TOS, the diameter of both the right (2.69 ± 0.30 mm in cases; 3.20 ± 0.19 mm in controls, P < .0001) and left (2.71 ± 0.26 mm in cases; 3.24 ± 0.15 mm controls, P < .0001) ON of study patients was smaller than controls. We observed a negative correlation between EDSS and both right (ρ = .524) and left (ρ = .469) ON diameter. We also observed a negative correlation between disease duration and both right (r = .602) and left (r = .538) ON diameter. No difference was observed in the diameter of both ON among patients with a history of optic neuritis (right OND 2.68 ± 0.29 mm; left OND 2.69 ± 0.25 mm) and patients with no history of optic neuritis (right OND 2.70 ± 0.30 mm; left OND 2.73 ± 0.27 mm) (P = .805; P = .651). CONCLUSIONS: The thickness of ON measured with TOS is correlated with EDSS and the duration of the disease without being interfered by the previous history of optic neuritis. TOS could be a reliable technique for measuring ON atrophy in MS.


Assuntos
Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia , Nervo Óptico/diagnóstico por imagem , Nervo Óptico/patologia , Ultrassonografia/métodos , Adulto , Atrofia/diagnóstico por imagem , Atrofia/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
J Nanosci Nanotechnol ; 18(4): 3006-3011, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442987

RESUMO

We present a study of adsorption of Cresyl Violet (CV) in aqueous solution on sonicated Graphite Oxide (sGO). For comparison, we also show adsorption results of Methylene Blue (MB) and Acridine Orange (AO) performed in the same conditions. The adsorbent was synthesized by the Tour's method followed by washing in water and ethanol and sonication, without any reduction, and studied by Raman, IR, UV-Vis, SEM and TEM techniques. Our results show that adsorption fits the pseudosecond order model for the three dyes, and that the adsorption quantity for CV is 125.0 mg g-1, while for MB and AO is 123.3 and 94.6 mg g-1 respectively.

16.
Andrologia ; 50(3)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29164653

RESUMO

In assisted reproductive techniques, it is essential to perform a sperm selection to obtain spermatozoa with high motility and membrane integrity for in vitro fertilisation (IVF) and high-DNA integrity for intracytoplasmic sperm injection (ICSI). In this study, we evaluated whether Isolate® was a suitable substitute for Percoll® for assisted reproductive techniques. Commercial cryopreserved bovine semen was used after selection in both gradients, and plasma and acrosome membrane integrity, reactive oxygen species (ROS) levels, DNA integrity and mitochondrial membrane potential (ΔΨm) were assessed by flow cytometry. Motility parameters were also evaluated by CASA system. A similar percentage of spermatozoa with intact plasma membrane, acrosome integrity and high ΔΨm was observed in both sperm selection methods, but only Percoll® showed higher percentage of spermatozoa with intact plasma and acrosome membrane compared to the post-thawing group. No differences were observed in the motility, ROS, DNA fragmentation and on the in vitro embryo production in all experimental groups. In conclusion, the selection of bovine spermatozoa with Isolate® generates spermatozoa with similar quality parameters and embryonic development compared to Percoll® providing a suitable alternative sperm selection method for assisted reproductive techniques in this species.


Assuntos
Técnicas de Reprodução Assistida/veterinária , Preservação do Sêmen/veterinária , Injeções de Esperma Intracitoplásmicas/veterinária , Espermatozoides/citologia , Acrossomo/metabolismo , Animais , Bovinos , Criopreservação , Fragmentação do DNA , Citometria de Fluxo , Masculino , Povidona , Dióxido de Silício , Motilidade dos Espermatozoides
17.
J Radiol Prot ; 38(2): 716-730, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29532785

RESUMO

This work describes the radiation characterisation and dosimetric measurements performed on the low-energy micromachining station of the femtosecond STELA (Santiago TErawatt LAser) at the University of Santiago de Compostela (Spain). For this aim, ionisation chambers, solid state detectors, and radiochromic films were used. The results show the emission of pulsed x-ray produced by laser-accelerated electrons from the ablated material exhibiting both bremsstrahlung and characteristic radiation. Although this radiation was produced unintentionally, a high superficial dose rate can be achieved. This radiation can be successfully stopped using small shielding to protect personnel from its effects. Based on the results of this work, the yearly dose equivalent after installing the shielding was negligible.


Assuntos
Terapia a Laser/métodos , Radiometria/métodos
18.
Cell Tissue Res ; 370(2): 305-317, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28770381

RESUMO

Diabetes mellitus in human and animal models has been correlated with low sperm count, testicular abnormalities, high levels of germ cell death, and oxidative stress. In this study, we focus on three questions: (1) Is germ cell apoptosis stage-specific in diabetic male rats? (2) Could ascorbic acid (AA) reverse oxidative and histological damage and restore testicular dysfunction? (3) Could AA treatment restore fertility parameters in diabetic rats? Adult Sprague-Dawley rats were divided into four groups: control, diabetic, control plus AA, and diabetic plus AA. Seminiferous tubules underwent severe histological damage, together with a change in frequency of some stages of the seminiferous cycle, and germ cell apoptosis was increased in a stage-dependent manner in diabetic rats. We found a significant decrease in testosterone and higher levels of lipid peroxidation in diabetic rats when compared with controls. A major finding was that AA reversed the histological damage and peroxidation levels to control levels in diabetic rats, but testosterone levels remained unchanged. The pregnancy rate was decreased in females that mated with diabetic rats and those treated with AA, but the litter size was only reduced in the second case. Interestingly, spermatozoa from diabetic and AA-treated rats showed reduced motility and hyperactivation, but only diabetic rats had higher levels of apoptosis when compared with controls. These results suggest that treatment with AA reverses testicular damage in diabetic rats but is insufficient to restore testosterone levels, sperm motility, and fertility in a rat model.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Diabetes Mellitus Experimental/complicações , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/etiologia , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Diabetes Mellitus Experimental/patologia , Infertilidade Masculina/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Espermatozoides/citologia , Espermatozoides/patologia , Testículo/citologia , Testículo/efeitos dos fármacos , Testículo/patologia , Vitaminas/farmacologia , Vitaminas/uso terapêutico
19.
Opt Express ; 25(12): 13372-13381, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28788874

RESUMO

We present the isolation of single attosecond pulses for multi-cycle and few-cycle laser pulses from high harmonic generation in overdense plasmas, calculated with particle-in-cell simulations. By the combination of two laser pulses of equal amplitude and a small frequency shift between them, we demonstrate that it is possible to shorten the region in which the laser pulse is most intense, therefore restricting the generation of high harmonic orders in the form of attosecond pulses to a narrower time window. The creation of this window is achieved due to the combination of the laser pulse envelope and the slow oscillating wave obtained from the coherent sum of the two pulses. A parametric scan, performed with particle-in-cell simulations, reveals how the pulse isolation behaves for different input laser pulse lengths and which are the optimal frequency shifts between the two laser pulses in each case, giving the conditions for having a good isolation of an attosecond pulse when working with laser-plasma interaction in overdense targets.

20.
Opt Express ; 25(13): 14974-14985, 2017 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-28788933

RESUMO

Plasmon resonances are known to amplify the electromagnetic fields near metallic nanostructures, providing a promising scheme to generate extreme-ultraviolet harmonics using low power drivings. During high-order harmonic generation (HHG), the driving and harmonic fields accumulate a phase difference as they propagate through the target. In a typical set-up -a laser focused into a gas jet- the propagation distances amount to several wavelengths, and the cumulative phase-mismatch affects strongly the efficiency and properties of the harmonic emission. In contrast, HHG in metallic nanostructures is considered to overcome these limitations, as the common sources of phase mismatch -optical density and focusing geometry- are negligible for subwavelength propagation distances. We demonstrate that phase matching still plays a relevant role in HHG from nanostructures due to the non-perturbative character of HHG, that links the harmonic phase to the intensity distribution of the driving field. Our computations show that widely used applications of phase matching control, such as quantum path selection and the increase of contrast in attosecond pulse generation, are also feasible at the nanoscale.

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