Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Más filtros












Intervalo de año de publicación
1.
BMC Pharmacol Toxicol ; 25(1): 62, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243062

RESUMEN

Higher olefins (HO) are a category of unsaturated hydrocarbons widely used in industry applications to make products essential for daily human life. Establishing safe exposure limits requires a solid data matrix that facilitates understanding of their toxicological profile. This in turn allows for data to be read across to other members of the category, which are structurally similar and have predictable physico-chemical properties. Five independent subchronic oral toxicity studies were conducted in Wistar rats with Oct-1-ene, Nonene, branched, Octadec-1-ene, Octadecene and hydrocarbon C12-30, olefin-rich, ethylene polymn. by product, at doses ranging from 20 to 1000 mg/kg bw. These HO were selected considering gut absorption, carbon chain length, double-bond position and carbon backbone structural variations. Generally, limited and non-adverse toxicity effects were observed at the end of the treatment for short carbon chain HO. For instance, alpha 2u-globulin nephropathy in the male rats and liver hypertrophy. No clear trend in systemic toxicity was linked to the double-bond position. Key factors for hazard assessment include absorption, carbon chain length, and branching, with Nonene, branched, identified as the worst-case substance. Taken together, the no observed adverse effect level (NOAEL) of each HO in these subchronic studies was set at the highest dose tested.


Asunto(s)
Alquenos , Ratas Wistar , Pruebas de Toxicidad Subcrónica , Animales , Masculino , Alquenos/toxicidad , Femenino , Ratas , Nivel sin Efectos Adversos Observados
2.
Clocks Sleep ; 6(3): 417-432, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39189195

RESUMEN

A randomized, double-blind and controlled study was conducted to assess the effectiveness of the intake of 250 mL of lactose-free skimmed milk enriched with ashwagandha (Withania somnifera) alone or combined with tryptophan vs. non-enriched milk (control) on the subjective quality of sleep in healthy adults with sleep problems. The duration of supplementation was 90 days. Fifty-two eligible subjects were assigned to the study arms of ashwagandha 250 mg, ashwagandha 250 mg plus tryptophan 175 mg, ashwagandha 600 mg, and control with 13 subjects in each group. It was hypothesized that ashwagandha plus tryptophan could be superior to ashwagandha alone for improving sleep-related variables. Changes in the visual analogue scale (VAS) for sleep quality were significantly higher in the three experimental groups as compared with controls (p = 0.014). Improvements in the subscales of the Pittsburg Sleep Quality Index (PSQI) were found in all groups, but between-group differences were not significant. In the index of insomnia severity, decreases were higher in the three experimental groups as compared with controls especially in the group of ashwagandha 600 mg. Daytime somnolence was also reduced in the three experimental groups. Changes in anxiety levels and Morningness-Eveningness Questionnaire were not observed. The study products did not elicit changes in body composition and were well tolerated and safe. The data did not support the hypothesis, as the combination of ashwagandha and tryptophan did not show greater benefits in improving sleep quality than ashwagandha alone. However, the results from the three experimental groups containing ashwagandha were more favorable compared to the placebo group.

3.
Front Nutr ; 11: 1405156, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38962436

RESUMEN

Objective: Smoking reduction or cessation are critical public health goals, given the well-documented risks of tobacco use to health. Reducing smoking frequency and cessation entirely are challenging due to nicotine addiction and withdrawal symptoms, which can significantly affect mental wellness and overall wellbeing. Previous research has suggested that certain dietary supplements may support smoking cessation and reduction efforts by mitigating these adverse effects. The objective of this study was to assess the effect of supplementation with 900 mg/day of Neuravena®, a green oat extract (GOE) of Avena sativa L., in enhancing wellness and wellbeing during a smoking reduction or cessation experience. Methods: This was an 8-week randomized, double-blind, placebo-controlled study, ClinicalTrials Identifier: NCT04749017 (https://classic.clinicaltrials.gov/ct2/show/NCT04749017). Participants were assigned to one of the study groups, 72 participants were assigned to GOE and 73 to placebo. The subjects were followed for 8-weeks intervention period as well as an additional 4-week follow-up period. At subsequent visits, they underwent clinical assessments including assessments of quality of life, perceived stress, depression, nicotine dependence, anxiety, cognitive performance, and specific assessments of craving intensity. Results: GOE was associated with greater improvements in elements of the abbreviated World Health Organization Quality of Life (WHOQOL-BREF) questionnaire as compared with placebo. Similar results were obtained from the SF-36 questionnaire and a visual QoL analogue scale (VAS). Perceived stress levels showed greater decline from baseline among the GOE supplemented participants as compared to placebo. Sleep quality parameters improved with GOE supplementation and worsened in the placebo group. At the end of the intervention period, the percentage of successful reducers (defined as >20% reduction in daily cigarettes) was higher in the GOE group as compared to placebo (66.7% vs. 49.3%, p = 0.034). The improvements from baseline in QoL measures in the GOE group persisted at 4 weeks after termination of the intervention. Conclusion: GOE supplementation demonstrated greater improvements in quality of life measures, stress and sleep related parameters during a smoking reduction or cessation experience and the product was shown to be safe and well tolerated.

4.
Arch Toxicol ; 98(8): 2487-2539, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38844554

RESUMEN

Alcohol ethoxylates (AEs) are a well-known class of non-ionic surfactants widely used by the personal care market. The aim of this study was to evaluate and characterize the in vitro metabolism of AEs and identify metabolites. Five selected individual homologue AEs (C8EO4, C10EO5, C12EO4, C16EO8, and C18EO3) were incubated using human, rat, and hamster liver S9 fraction and cryopreserved hepatocytes. LC-MS was used to identify metabolites following the incubation of AEs by liver S9 and hepatocytes of all three species. All AEs were metabolized in these systems with a half-life ranging from 2 to 139 min. In general, incubation of AE with human liver S9 showed a shorter half-life compared to rat liver S9. While rat hepatocytes metabolized AEs faster than human hepatocytes. Both hydrophobic alkyl chain and hydrophilic EO head group groups of AEs were found to be target sites of metabolism. Metabolites were identified that show primary hydroxylation and dehydrogenation, followed by O-dealkylation (shortening of EO head groups) and glucuronidation. Additionally, the detection of whole EO groups indicates the cleavage of the ether bond between the alkyl chain and the EO groups as a minor metabolic pathway in the current testing system. Furthermore, no difference in metabolic patterns of each individual homologue AE investigated was observed, regardless of alkyl chain length or the number of EO groups. Moreover, there is an excellent agreement between the in vitro experimental data and the metabolite profile simulations using in silico approaches (OECD QSAR Toolbox). Altogether, these data indicate fast metabolism of all AEs with a qualitatively similar metabolic pathway with some quantitative differences observed in the metabolite profiles. These metabolic studies using different species can provide important reference values for further safety evaluation.


Asunto(s)
Hepatocitos , Animales , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Humanos , Proyectos Piloto , Masculino , Ratas , Redes y Vías Metabólicas , Simulación por Computador , Cricetinae , Tensoactivos/metabolismo , Tensoactivos/toxicidad , Especificidad de la Especie , Semivida , Hígado/metabolismo , Cromatografía Liquida , Glicoles de Etileno/metabolismo , Glicoles de Etileno/toxicidad , Ratas Sprague-Dawley
5.
Front Nutr ; 11: 1403108, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887495

RESUMEN

Background: Back pain is a common health problem that affects both workers and older people, reducing their quality of life. The primary objective was to assess the effect of dietary supplementation with plant extracts of rosemary, ashwagandha, and sesame consumed for 12 weeks on the intensity of back pain. Methods: A single-center randomized double-blind study with three parallel arms depending on the product consumed. The duration of treatment was 12 weeks. The investigational product, Berelief®, contained a blend of three polyphenolic standardized extracts: rosemary (Rosmarinus officinalis L.), ashwagandha (Withania somnifera L.), and sesame (Sesamum indicum L.) seed. Two doses were tested: low dose (400 mg) and high dose (800 mg). There were 42 subjects in the placebo group, 39 in the low dose and 42 in the high dose groups. Study variables included back pain intensity [VAS score, Patient-Reported Outcomes Measurement Information System (PROMIS-29), and Cornell Musculoskeletal Discomfort Questionnaire; functionality Roland-Morris Disability (RMD) questionnaire]; quality of life (QoL) [36-item Short Form Survey (SF-36), the Beck Depression Inventory-II (BDI-II), the State-Trait Anxiety Inventory (STAI), and the Perceived Stress Scale (PSS)]; sleep quality [accelerometer and Pittsburgh Sleep Quality Index (PSQI)]. Results: The improvement in back pain recorded by the visual analogue scale (VAS) at the study visits after the beginning of treatment, as well as on a weekly basis recorded in the diary card was significantly higher in the intervention group than in the placebo group (p < 0.044 dose-low; p < 0.005 dose-high). Significant differences in pain intensity of the PROMIS-29 (p = 0.002) and upper back pain in the Cornell questionnaire (p = 0.011) in favour of the investigational product were found. Furthermore, benefits in improving health-related quality of life, mood and sleep quality were also detected. Conclusion: Dietary supplementation for 12 weeks of a blend of polyphenolic standardized extracts of rosemary, ashwagandha, and sesame was effective in reducing the intensity of pain in subjects with chronic myofascial cervical and back pain.

6.
Nutrients ; 16(10)2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38794761

RESUMEN

Seventy-one healthy subjects with sleep disturbances participated in a randomized, double-blind controlled trial in which dietary supplementation with an extract of Aloysia citrodora (lemon verbena) (n = 33) or placebo (n = 38) was administered for 90 days. There were between-group differences in favor of the experimental group in the visual analogue scale (VAS) for sleep quality (6.5 ± 1.6 vs. 5.5 ± 2.1, p = 0.021) as well as in the overall score (5.8 ± 2.4, p = 0.008) and scores for sleep latency (1.6 ± 1.0 vs. 1.9 ± 0.7, p = 0.027) and sleep efficiency (84.5 ± 12.8 vs. 79.8 ± 13.6, p = 0.023) in the Pittsburgh Sleep Quality Index (PSQI). Sleep-related variables (latency, efficiency, wakefulness after sleep onset, awakenings) assessed by actigraphy also showed better scores in the experimental group (p = 0.001). Plasma nocturnal melatonin levels also increased significantly in the experimental group (199.7 ± 135.3 vs. 174.7 ± 115.4 pg/mL, p = 0.048). Changes in anthropometric parameters and physical activity levels were not found. In summary, a dietary supplement of lemon verbena administered for 3 months was associated with a significant improvement in sleep quality as compared with placebo in a population of healthy subjects with sleep problems.


Asunto(s)
Suplementos Dietéticos , Extractos Vegetales , Calidad del Sueño , Humanos , Método Doble Ciego , Masculino , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Femenino , Adulto , Persona de Mediana Edad , Melatonina/administración & dosificación , Voluntarios Sanos , Adulto Joven , Sueño/efectos de los fármacos , Trastornos del Sueño-Vigilia
7.
Arch Toxicol ; 98(2): 551-565, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38085275

RESUMEN

The present study evaluates the in vitro developmental toxicity and the possible underlying mode of action of DMSO extracts of a series of highly complex petroleum substances in the mouse embryonic stem cell test (mEST), the zebrafish embryotoxicity test (ZET) and the aryl hydrocarbon receptor reporter gene assay (AhR CALUX assay). Results show that two out of sixteen samples tested, both being poorly refined products that may contain a substantial amount of 3- to 7-ring polycyclic aromatic compounds (PACs), induced sustained AhR activation in the AhR CALUX assay, and concentration-dependent developmental toxicity in both mEST and ZET. The other samples tested, representing highly refined petroleum substances and petroleum-derived waxes (containing typically a very low amount or no PACs at all), were negative in all assays applied, pointing to their inability to induce developmental toxicity in vitro. The refining processes applied during the production of highly refined petroleum products, such as solvent extraction and hydrotreatment which focus on the removal of undesired constituents, including 3- to 7-ring PACs, abolish the in vitro developmental toxicity. In conclusion, the obtained results support the hypothesis that 3- to 7-ring PACs are the primary inducers of the developmental toxicity induced by some (i.e., poorly refined) petroleum substances and that the observed effect is partially AhR-mediated.


Asunto(s)
Petróleo , Hidrocarburos Policíclicos Aromáticos , Ratones , Animales , Petróleo/toxicidad , Petróleo/análisis , Pez Cebra , Células Madre Embrionarias de Ratones
8.
Int J Toxicol ; : 10915818231210856, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936376

RESUMEN

Higher olefins (HO) are used primarily as intermediates in the production of other chemicals, such as polymers, fatty acids, plasticizer alcohols, surfactants, lubricants, amine oxides, and detergent alcohols. The potential toxicity of five HO (i.e., 1-Octene, Nonene, Decene, Hexadecene, and 1-Octadecene) with carbon ranging from C8 to C18 was examined in a combined repeated dose and reproduction/developmental toxicity screening study (OECD TG 422). These five HO were administered to Han Wistar rats by gavage at 0 (controls), 100, 300, and 1000 mg/kg bw/day. As a group of substances, adaptive changes in the liver (liver weight increase without pathological evidence), as well as increased kidney weight in male rats, were observed in HO with carbon numbers from C8 to C10. The overall systemic no observed adverse effect level (NOAEL) for all HO was determined at 1000 mg/kg bw/day. In the reproductive/developmental toxicity assessment, offspring viability, size, and weights were reduced in litters from females treated with Nonene at 1000 mg/kg bw/day. The overall no observed effects level (NOEL) for reproductive toxicity was considered to be 300 mg/kg bw/day for Nonene and 1000 mg/kg bw/day for the other four HO, respectively. These data significantly enrich the database on the toxicity of linear and branched HO, allowing comparison with similar data published on a range of linear and branched HO. Comparisons between structural class and study outcome provide further supportive data in order to validate the read-across hypothesis as part of an overall holistic testing strategy.

9.
Nutrients ; 15(17)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37686880

RESUMEN

A single-center, randomized, double-blind, controlled clinical trial with four arms was conducted in healthy subjects with persistent knee discomfort (pain intensity on 1-10 cm visual analog scale (VAS) > 3) aged 40 years and older treated with a dietary supplement for 8 weeks. The study groups were Boswellia serrata extract (n = 29), an omega-3-based product (AvailOm® 50 High EPA) (n = 31), Boswellia + AvailOm® (n = 30), and placebo (n = 30). The intake of Boswellia + AvailOm® improved the quality of life (QoL) (WOMAC index) and some variables of muscle strength. Statistically significant differences between the AvailOm® and the placebo groups in the decrease of pain intensity were found. Weekly VAS scores showed a significant decrease in pain perception when comparing the AvailOm® product to the placebo, with the lowest VAS scores at week 8. Consumption of Boswellia improved sleep latency. The time to perform the Up and Go test decreased after the intake of AvailOm®. There was an increase in the omega-3 fatty acids, with the greatest increase in the Boswellia + AvailOm® group. AvailOm® was safe and effective in reducing pain and improving the QoL and functionality of subjects over 40 years with persistent knee pain.


Asunto(s)
Boswellia , Ácidos Grasos Omega-3 , Humanos , Adulto , Persona de Mediana Edad , Calidad de Vida , Dolor , Ácidos Grasos Omega-3/uso terapéutico , Extractos Vegetales/uso terapéutico
10.
Chem Res Toxicol ; 35(8): 1383-1392, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35830964

RESUMEN

To reduce the number of animals and studies needed to fulfill the information requirements as required by Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) (EC no. 1907/2006), a read-across approach was used to support approximately 30 higher olefins. This study aimed to assess the absorption potential of higher olefins through the gut wall as the experimentally determined bioavailability which would strengthen the read-across hypothesis and justification, reducing the need for toxicity studies on all of the higher olefins. The absorption potential of a series of higher olefins (carbon range from 6 to 28, with five configurations of the double bond) was determined in the in vitro everted rat small intestinal sac model and subsequently ranked. In addition, in silico approaches were applied to predict the reactivity, lipophilicity, and permeability of higher olefins. In the in vitro model, everted sacs were incubated in "fed-state simulated small intestinal fluid" saturated with individual higher olefins. The sac contents were then collected, extracted, and analyzed for olefin content using gas chromatography with a flame ionization detector. The C6 to C10 molecules were readily absorbed into the intestinal sacs. Marked inter-compound differences were observed, with the amount of absorption generally decreasing with the increase in carbon number. Higher olefins with ≥C14 carbons were either not absorbed or very poorly absorbed. In the reactivity simulation study, the reactivity is well described by the position of the double bond rather than the number of carbon atoms. In the lipophilicity and permeability analysis, both parameter descriptors depend mainly on the number of carbon atoms and less on the position of the double bond. In conclusion, these new approach methodologies provide supporting information on any trends or breakpoints in intestinal uptake and a hazard matrix based on carbon number and position of the double bond. This matrix will further assist in the selection of substances for inclusion in the mammalian toxicity testing programme.


Asunto(s)
Alquenos , Absorción Intestinal , Animales , Carbono/metabolismo , Intestino Delgado , Mamíferos , Permeabilidad , Ratas
11.
Regul Toxicol Pharmacol ; 132: 105193, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35618173

RESUMEN

The carcinogenicity and developmental toxicity of unrefined mineral oil is related to its 3-7 ring polycyclic aromatic compounds (PAC) content. Therefore, refining operations focus on the targeted removal PAC from mineral oil that may contain aromatics of low toxicological concern. There are thus, two types of aromatic substances in mineral oil: hazardous and non-hazardous. The first type consists of 3-7 ring PAC which may be naked (unsubstituted) or lowly alkylated. The second type or non-hazardous consists of 1-7 ring aromatics with high degree of alkylation or lack of bay or fjord regions. Although these are toxicologically different, they may both elute in the same fraction when using chromatography. To understand how these two aromatic types are related we have assessed the entire mineral oil refinement process by measuring total mineral oil aromatic hydrocarbons (MOAH) content by chromatography next to regulatory hazard tests which focus on 3-7 ring PAC. MOAH content is positively correlated to its molecular weight resulting in aromatic content bias for high viscosity substances. Hazard to 3-7 ring PAC is best controlled by the validated IP346 or modified Ames test. We explain the concept of high vs low alkylation by shortly reviewing new data on alkylated PAC.


Asunto(s)
Hidrocarburos Aromáticos , Compuestos Policíclicos , Carcinogénesis , Carcinógenos/toxicidad , Humanos , Hidrocarburos Aromáticos/análisis , Aceite Mineral/química , Aceite Mineral/toxicidad , Minerales , Aceites
12.
Sci Total Environ ; 832: 154802, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35346703

RESUMEN

This work investigated the occurrence and risks associated with polycyclic aromatic hydrocarbons (PAHs) in tissues from five commonly consumed aquatic species (swimming crabs, estuarine shrimp, tiger prawns, periwinkles, and tilapia) and sediment across six sites in the area around Bodo town, in the Niger Delta region of Nigeria. We aimed to establish a relationship between PAH concentrations in sediment and biota, and to derive biota-sediment accumulation factors (BSAFs). Risks to human health associated with consumption of impacted food sources were assessed based on measured biotic concentrations of PAHs. The average concentration of PAHs and the number of PAHs measured above the limit of quantification varied greatly between different biota, with the lowest average concentrations observed in tilapia, followed by tiger prawns, crabs, estuarine shrimp, and the highest concentrations were observed in periwinkles. Similar to biotic concentrations, BSAFs were found to vary greatly across species, sites, and PAHs, though BSAFs for all organisms except periwinkles were below a value of 1. In periwinkles, BSAFs exceeded a value of 1 for phenanthrene (BSAF = 1.7), pyrene (1.5) and benzo[k]fluoranthene (1.7). Risks to human health associated with consumption of these species were assessed using the BaP toxic-equivalent approach for cancer risks and the toxic unit approach which jointly considered carcinogenic but also non-cancer hazards. The BaP toxic-equivalent approach showed that the excess lifetime cancer risk resulting from daily consumption of 0.2 kg of seafood ranged between 1.3 × 10-6 for tiger prawn and tilapia to 4.1 × 10-6 for periwinkles, which is below the excess lifetime cancer risk of 10-4 used by Dutch and Nigerian authorities for sediment intervention values. This finding is supported by the results obtained from the toxic unit approach which indicates that the ratios of the estimated dose and the maximal permissible risk level for summed PAHs never exceeded 1.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Animales , Bioacumulación , Crustáceos , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Humanos , Niger , Nigeria , Hidrocarburos Policíclicos Aromáticos/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
13.
Food Chem Toxicol ; 159: 112701, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34838897

RESUMEN

Oral exposure to mineral oil may result in a narrow fraction of mineral oil saturated hydrocarbon (MOSH) being retained in tissues. Excess of MOSH hepatic retention may lead to the formation of lipogranuloma caused by predominantly multiring cycloalkanes (naphthenics) in a critical range of C25-C35. Although hepatic lipogranuloma is of low pathological concern, MOSH tissue deposition could be minimized by using an oil of similar quality but devoid of naphthenic structures to decrease hepatic retention. Synthetic Gas to liquid (GTL) oils offer an alternative to petroleum derived mineral oils, because they do not contain naphthenic structures. To demonstrate this point, SD rats were fed either GTL oil (99% iso-alkanes) or naphthenic mineral oil (84% cycloalkanes) at 200 mg/kg bw/day for 90 or 134 days with a recovery group. Liver, fat and mesenteric lymph nodes were analyzed for alkane sub-type levels using Online-HPLC-GC-FID and GCxGC-TOF-MS. Results indicate that at equal external dose, GTL hydrocarbons result in lower tissue levels and more rapid excretion than MOSH. GTL retained hepatic fractions were also qualitatively different than MOSH constituents. Because chemical composition differences, GTL oil show low absorption and tissue retention potential and thus an advantageous alternative to conventional mineral oil.


Asunto(s)
Hígado , Aceite Mineral , Aceites , Parafina , Animales , Cicloparafinas/química , Cicloparafinas/metabolismo , Femenino , Hígado/efectos de los fármacos , Hígado/metabolismo , Ganglios Linfáticos/metabolismo , Aceite Mineral/química , Aceite Mineral/metabolismo , Aceite Mineral/farmacocinética , Aceites/química , Aceites/metabolismo , Aceites/farmacocinética , Parafina/química , Parafina/metabolismo , Parafina/farmacocinética , Ratas , Ratas Sprague-Dawley , Distribución Tisular
14.
Nutrients ; 13(12)2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34959924

RESUMEN

The aim of a 12-week randomized double-blind placebo-controlled study was to assess the effect of daily supplementation with a natural extract of Spinacia oleracea L. (4 × 500 mg capsules/day; total 2 g per day) combined with a moderate-intensity training program (1 h session/3 times a week) on skeletal muscle fitness in adults over 50 years of age. Muscle strength assessed by isokinetic and isometric dynamometry improved significantly in the experimental (n = 23) and the placebo (n = 22) groups, but the magnitude of improvement was higher in the experimental group, with between-group differences in almost all variables, including isokinetic at 60° s-1 in knee extension, peak torque (p < 0.007); total work per repetition maximum (p < 0.009); isokinetic at 180°s-1 in knee extension, peak torque (p < 0.002); total work (p < 0.007); total work per repetition maximum (p < 0.005); average power (p < 0.027); isometric in knee extension, peak torque (p < 0.005); and average peak torque (p < 0.002). Similar findings were observed for muscle quality. Changes in quality of life (SF-36) were not found, except for improvements in the role physical (p < 0.023) and role emotional (p < 0.001) domains, likely as a result of the physical training sessions. A nutritional survey did not revealed changes in dietary habits. No adverse events were recorded. In subjects over 50 years of age, moderate-intensity strength training combined with daily supplementation for 12 weeks with a natural extract of Spinacia oleracea L. improved muscle-related variables and muscle quality. Maintaining muscle health is a key component of healthy aging.


Asunto(s)
Suplementos Dietéticos , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/fisiología , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Sarcopenia/prevención & control , Spinacia oleracea/química , Factores de Edad , Anciano , Método Doble Ciego , Femenino , Envejecimiento Saludable/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Fitoterapia , Sarcopenia/fisiopatología , Factores de Tiempo
15.
Regul Toxicol Pharmacol ; 127: 105054, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34653553

RESUMEN

Reproductive toxicity chemical safety assessment involves extensive use of vertebrate animals for regulatory testing purposes. Although alternative methods such as the zebrafish embryo teratogenicity assay (identified in the present manuscript by the acronym ZETA) are promising for replacing tests with mammals, challenges to regulatory application involve lack of standardization and incomplete validation. To identify key protocol aspects and ultimately support improving this situation, a comprehensive review of the literature on the level of harmonization/standardization and validation status of the ZETA has been conducted. The gaps and needed advances of the available ZETA protocols were evaluated and discussed with respect to its applicability as an alternative approach for teratogenicity assessment. Based on the review outcomes, a set of minimum reporting standards for the experimental protocol is proposed. Together with other initiatives towards implementation of alternative approaches at the screening and regulatory levels, the application of minimum reporting requirements is anticipated to support future method standardization and validation, as well as identifying potential improvement aspects. Present findings are expected to ultimately support advancing the ongoing validation initiatives towards the regulatory acceptance of the ZETA.


Asunto(s)
Documentación/normas , Embrión no Mamífero , Teratógenos/toxicidad , Pruebas de Toxicidad/métodos , Pruebas de Toxicidad/normas , Pez Cebra , Animales
16.
Crit Rev Toxicol ; 51(5): 418-455, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34494504

RESUMEN

Paraffin waxes and white mineral oils are distinct petroleum products separated from a common feedstock by crystallization, where only n-alkanes, iso- and cyclo-alkanes with a linear backbone of ∼ 20 carbon atoms long, selectively crystalize out from the oil to form the wax, which is solid at room temperature, whereas oils remain liquid. Up until the 90's, these differences were reflected in separated regulatory assessments. A paradigm shift occurred when Fischer 344 rats (F-344) developed liver epithelioid granuloma following exposure to low and medium viscosity oils or waxes. This lesion was used as common denominator between these products to be jointly assessed under the common term "mineral hydrocarbons - MHC", obviating compositional differences. This regulatory paradigm dominated for the next 30 years, exacerbated by the EFSA 2012 evaluation using the analytical term "MOSH" (mineral oil saturated hydrocarbons) which encompassed these products under single chromatography fraction. The reconstruction of historical developments, together with recent EFSA-sponsored studies of toxicity and accumulation and supporting literature, has allowed us to understand the etiology of the F-344 rat hepatic epithelioid granuloma, which is presented in an adverse outcome pathway (AOP). Considering chemical composition, it clearly demonstrates that the hepatic effects in F-344 rats caused by linear alkanes of waxes are irrelevant for humans. Waxes are thus not MOSH and should thus be evaluated on their own merit. The term MOSH should not include n-alkanes and be exclusively used to mineral oil fractions when considering their chemical makeup for a relevant human hazard assessment.


Asunto(s)
Hidrocarburos , Aceite Mineral , Animales , Hidrocarburos/toxicidad , Aceite Mineral/toxicidad , Aceites , Ratas , Medición de Riesgo , Ceras/toxicidad
17.
Biology (Basel) ; 10(3)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799555

RESUMEN

Due to COVID-19, wearing a face mask to reduce virus transmission is currently mandatory in some countries when participants practice exercise in sports centers. Therefore, the aim of the present study was to analyze the effect of wearing a surgical or FFP2 mask during a resistance training session. Fourteen people with sarcopenia (age: 59.40 ± 5.46 years; weight: 68.78 ± 8.31 kg; height: 163.84 ± 9.08 cm) that participated in the study performed three training sessions in a randomized order: 4 sets of 10 repetitions of a half-squat at 60% of the one-repetition maximum and 90 s of rest between set and were either (a) without a mask (NM), (b) wearing a surgical face mask (SM), and (c) wearing a FFP2 face mask (FFP2). We found that wearing face masks had no effect on strength performance (session mean propulsive velocity (m/s): WM: 0.396 ± 0.042; SM: 0.387 ± 0.037; and FFP2: 0.391 ± 0.042 (p = 0.918)). Additionally, no impact of wearing a mask was found on heart rate, heart rate variability, blood lactate concentration (WM: 4.17 ± 1.89; SM: 4.49 ± 2.07; and FFP2: 5.28 ± 2.45 mmol/L (p = 0.447)), or rating of perceived exertion. Wearing a surgical or FFP2 face mask during a resistance training session resulted in similar strength performance and physiological responses than the same exercise without a mask in persons with sarcopenia.

20.
J Am Coll Emerg Physicians Open ; 1(6): 1418-1426, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33392546

RESUMEN

Coronavirus disease 2019 (COVID-19) is associated with a severe acute respiratory condition requiring respiratory support and mechanical ventilation. Based on the pathophysiology and clinical course of the disease, a therapeutic approach can be adapted. Three phases have been identified, in which different strategies are recommended in a stepwise invasiveness approach. In the second or acute phase, patients are frequently admitted to the ICU for severe pneumonia and hypoxemia with evidence of a proinflammatory and hypercoagulable state. This stage is an opportunity to intervene early in the disease. Medical strategies and mechanical ventilation should be individualized to improve outcomes.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...