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1.
Antibiotics (Basel) ; 13(7)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39061316

RESUMO

The emergence of antimicrobial resistance (AMR) is a significant threat to global food security, human health, and the future of livestock production. Higher rates of antimicrobial use in dairy farming and the sheer lack of new antimicrobials available for use focused attention on the question of how the dairy production sector contributed to the development of AMR and paved the path toward taking action to curtail it on the targeted type of farms. This paper aims to provide an introduction to a phenomenon that has gained considerable attention in the recent past due to its ever-increasing impact, the use of antimicrobial drugs, the emergence of antimicrobial resistance (AMR) on dairy farms, and seeks to discuss the possibilities of approaches such as digital health monitoring and precision livestock farming. Using sensors, data, knowledge, automation, etc., digital health monitoring, as well as Precision Livestock Farming (PLF), is expected to enhance health control and minimize disease and antimicrobial usage. The work presents a literature review on the current status and trends of AMR in dairy farms, an understanding of the concept of digital health monitoring and PLF, and the presentation and usefulness of digital health monitoring and PLF in preventing AMR. The study also analyses the strengths and weaknesses of adopting and incorporating digital technologies and artificial intelligence for dairy farming and presents areas for further study and level of use.

2.
Sci Rep ; 14(1): 14866, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937505

RESUMO

Radiation delivery at ultrahigh dose rates (UHDRs) has potential for use as a new anticancer therapeutic strategy. The FLASH effect induced by UHDR irradiation has been shown to maintain antitumour efficacy with a reduction in normal tissue toxicity; however, the FLASH effect has been difficult to demonstrate in vitro. The objective to demonstrate the FLASH effect in vitro is challenging, aiming to reveal a differential response between cancer and normal cells to further identify cell molecular mechanisms. New high-intensity petawatt laser-driven accelerators can deliver very high-energy electrons (VHEEs) at dose rates as high as 1013 Gy/s in very short pulses (10-13 s). Here, we present the first in vitro experiments carried out on cancer cells and normal non-transformed cells concurrently exposed to laser-plasma accelerated (LPA) electrons. Specifically, melanoma cancer cells and normal melanocyte co-cultures grown on chamber slides were simultaneously irradiated with LPA electrons. A non-uniform dose distribution on the cell cultures was revealed by Gafchromic films placed behind the chamber slide supporting the cells. In parallel experiments, cell co-cultures were exposed to pulsed X-ray irradiation, which served as positive controls for radiation-induced nuclear DNA double-strand breaks. By measuring the impact on discrete areas of the cell monolayers, the greatest proportion of the damaged DNA-containing nuclei was attained by the LPA electrons at a cumulative dose one order of magnitude lower than the dose obtained by pulsed X-ray irradiation. Interestingly, in certain discrete areas, we observed that LPA electron exposure had a different effect on the DNA damage in healthy normal human epidermal melanocyte (NHEM) cells than in A375 melanoma cells; here, the normal cells were less affected by the LPA exposure than cancer cells. This result is the first in vitro demonstration of a differential response of tumour and normal cells exposed to FLASH irradiation and may contribute to the development of new cell culture strategies to explore fundamental understanding of FLASH-induced cell effect.


Assuntos
Técnicas de Cocultura , Elétrons , Lasers , Humanos , Técnicas de Cocultura/métodos , Linhagem Celular Tumoral , Melanócitos/efeitos da radiação , Dano ao DNA , Melanoma/radioterapia , Melanoma/patologia , Quebras de DNA de Cadeia Dupla/efeitos da radiação
3.
Molecules ; 26(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199757

RESUMO

The innovative strategy of using nanoparticles in radiotherapy has become an exciting topic due to the possibility of simultaneously improving local efficiency of radiation in tumors and real-time monitoring of the delivered doses. Yttrium oxide (Y2O3) nanoparticles (NPs) are used in material science to prepare phosphors for various applications including X-ray induced photodynamic therapy and in situ nano-dosimetry, but few available reports only addressed the effect induced in cells by combined exposure to different doses of superficial X-ray radiation and nanoparticles. Herein, we analyzed changes induced in melanoma cells by exposure to different doses of X-ray radiation and various concentrations of Y2O3 NPs. By evaluation of cell mitochondrial activity and production of intracellular reactive oxygen species (ROS), we estimated that 2, 4, and 6 Gy X-ray radiation doses are visibly altering the cells by inducing ROS production with increasing the dose while at 6 Gy the mitochondrial activity is also affected. Separately, high-concentrated solutions of 25, 50, and 100 µg/mL Y2O3 NPs were also found to affect the cells by inducing ROS production with the increase of concentration. Additionally, the colony-forming units assay evidenced a rather synergic effect of NPs and radiation. By adding the NPs to cells before irradiation, a decrease of the number of proliferating cell colonies was observed with increase of X-ray dose. DNA damage was evidenced by quantifying the γ-H2AX foci for cells treated with Y2O3 NPs and exposed to superficial X-ray radiation. Proteomic profile confirmed that a combined effect of 50 µg/mL Y2O3 NPs and 6 Gy X-ray dose induced mitochondria alterations and DNA changes in melanoma cells.


Assuntos
Melanoma/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ítrio/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Melanoma/terapia , Mitocôndrias/efeitos dos fármacos , Nanopartículas , Tamanho da Partícula , Fotoquimioterapia , Proteômica
4.
Health Phys ; 119(1): 101-108, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32483045

RESUMO

Ionizing radiation exposure produces direct or indirect biological effects on genomic DNA. The latter are ionizing radiation mediated by induction of free radicals and oxygen species (ROS). The study was conducted to evaluate the dose-effect/time-effect of antioxidant treatments in reducing the induction of double-strand breaks in human blood lymphocytes. Human peripheral blood samples of 2 mL each from healthy donors were irradiated with 10 mGy after pre-incubation with different antioxidants (ß-carotene, vitamin E, vitamin C, N-acetyl L-cysteine). In order to assess their efficiency as prophylactic therapy for irradiation, various concentrations and combinations of antioxidants, as well as different incubation times, have been evaluated. To assess double-strand breaks induced by ionizing radiation, the phosphorylated histone γ-H2AX has been used. A significant reduction (p < 0.001) in double-strand breaks studied with a γ-H2AX assay was observed with N-acetyl L-cysteine with a 1-h incubation time, followed by vitamin C, vitamin E, and ß-carotene. The use of antioxidants, especially N-acetyl L-cysteine before irradiation, significantly decreased the occurrence of double-strand breaks, demonstrating the potential radiological protection for exposure to ionizing radiation.


Assuntos
Antioxidantes/farmacologia , Células Sanguíneas/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA/efeitos da radiação , Histonas/efeitos da radiação , Linfócitos/efeitos da radiação , Acetilcisteína/farmacologia , Ácido Ascórbico/farmacologia , Relação Dose-Resposta à Radiação , Histonas/genética , Humanos , Microscopia de Fluorescência , Doses de Radiação , Radiação Ionizante , Radiografia , Espécies Reativas de Oxigênio/efeitos da radiação , Vitamina E/farmacologia , Raios X , beta Caroteno/farmacologia
5.
Methods Appl Fluoresc ; 8(3): 035005, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32320952

RESUMO

In recent years, luminescence nanothermometers with near infrared light (NIR) emission excited in the NIR range have attracted much attention due to their potential in bio applications. Here, we propose a new nanothermometer based on triple doped 1%Ho, 1%Er, 1%Yb - Y2O3 that operates in the second and third biological windows around 1200 and 1530 nm under pulsed excitation at 905 nm. The NIR emissions were analysed in the temperature range of 298-473 K in terms of intensity, shape and dynamics. The nanothermometer performances were described using the luminescent intensity ratio (LIR) corresponding to the 5I6-5I8 and 4I13/2-4I15/2 emissions transitions of Ho and Er, respectively. A maximum relative sensitivity of 1.5% K-1 was achieved at 309 K, which is among the highest five values reported so far for the NIR to NIR downconversion nanothermometers. The thermometer performance for biological application was assessed in terms of nanothermometer reliability and stability as well as emission shape changes induced by water and custom designed optical phantoms. Combination between use of pulsed excitation and identification of Ln doping configuration offering both excitation and emission in the biological windows represent a solid approach that can be easily translated to other hosts to develop a new class of near infrared nanothermometers.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ítrio/química , Humanos
6.
Materials (Basel) ; 12(24)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817618

RESUMO

Reduced activation ferritic and martensitic steel like EUROFER (9Cr-1W) are considered as potential structural materials for the first wall of the future next-generation DEMOnstration Power Station (DEMO) fusion reactor and as a reference material for the International Thermonuclear Experimental Reactor (ITER) test blanket module. The primary motivation of this work is to study the re-deposition of the main constituent materials of EUROFER, namely tungsten (W), iron (Fe), and chromium (Cr), in a DEMO type reactor by producing and analyzing complex WxCryFe1-x-y layers. The composite layers were produced in laboratory using the thermionic vacuum arc (TVA) method, and the morphology, crystalline structure, elemental composition, and mechanical properties were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), micro-X-ray fluorescence (micro-XRF), and glow discharge optical emission spectrometry (GDOES), as well as nanoindentation and tribology measurements. The results show that the layer morphology is textured and is highly dependent on sample positioning during the deposition process. The formation of polycrystalline WxCryFe1-x-y was observed for all samples with the exception of the sample positioned closer to Fe anode during deposition. The crystalline grain size dimension varied between 10 and 20 nm. The composition and thickness of the layers were strongly influenced by the in-situ coating position, and the elemental depth profiles show a non-uniform distribution of Fe and Cr in the layers. The highest hardness was measured for the sample positioned near the Cr anode, 6.84 GPa, and the lowest was 4.84 GPa, measured for the sample positioned near the W anode. The tribology measurements showed an abrasive sliding wear behavior for most of the samples with a reduction of the friction coefficient with the increase of the normal load.

7.
Tob Induc Dis ; 16: 13, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31516413

RESUMO

INTRODUCTION: Smoking cessation is a key clinical intervention for reducing progressive lung destruction and lung function deterioration in patients with Chronic Obstructive Pulmonary Disease (COPD). Specialised Tobacco Cessation Guidelines for High-risk Groups (TOB-G) were developed and published in 2017 that present evidence-based recommendations to support smoking cessation in COPD patients. The purpose of this pilot study was to examine the real world effectiveness of the TOB-G guideline recommendations among a sample of COPD patients. METHODS: A pilot study was conducted among a sample of COPD patients who smoke and were interested in quitting. Participants were recruited from inpatient and outpatient hospital admissions between October and December 2016 in Iasi, Romania. The intervention program was designed based on the recommendations of the TOB-G guidelines for COPD patients. Patients received a total of four contacts: at baseline, 1, 2, and 6 months. The primary outcome measure was biochemically validated point prevalence smoking abstinence measured at 6 months. RESULTS: Fifty patients (74% male; age mean±SD = 60.2±7.8) with diagnosed COPD took part in the pilot study. Self-reported rates of point prevalence smoking abstinence were 30.6%, 44.9% and 64.6% at the 1-, 2-, and 6-month follow-up, respectively. Carbon monoxide testing was completed with 51.6% of the sample at 6 months. The biochemically verified abstinent rate was 33.3% at the 6-month follow-up. CONCLUSIONS: This pilot testing of the TOB-G Clinical Practice Guidelines for COPD patients was associated with high rates of patient smoking abstinence, which are of clinical importance. Further research is needed to evaluate the guidelines large-scale effectiveness in clinical practice.

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