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1.
Sci Rep ; 14(1): 9134, 2024 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644380

RESUMEN

Prolonged exposure to iron powder and other mineral dusts can threaten the health of individuals, especially those with COPD. The goal of this study was to determine how environmental exposure to metal dust from two different mining centers in Brazil affects lung mechanics, inflammation, remodeling and oxidative stress responses in healthy and elastase-exposed mice. This study divided 72 male C57Bl/6 mice into two groups, the summer group and the winter group. These groups were further divided into six groups: control, nonexposed (SAL); nonexposed, given elastase (ELA); exposed to metal powder at a mining company (SAL-L1 and ELA-L1); and exposed to a location three miles away from the mining company (SAL-L2 and ELA-L2) for four weeks. On the 29th day of the protocol, the researchers assessed lung mechanics, bronchoalveolar lavage fluid (BALF), inflammation, remodeling, oxidative stress, macrophage iron and alveolar wall alterations (mean linear intercept-Lm). The Lm was increased in the ELA, ELA-L1 and ELA-L2 groups compared to the SAL group (p < 0.05). There was an increase in the total number of cells and macrophages in the ELA-L1 and ELA-L2 groups compared to the other groups (p < 0.05). Compared to the ELA and SAL groups, the exposed groups (ELA-L1, ELA-L2, SAL-L1, and SAL-L2) exhibited increased expression of IL-1ß, IL-6, IL-10, IL-17, TNF-α, neutrophil elastase, TIMP-1, MMP-9, MMP-12, TGF-ß, collagen fibers, MUC5AC, iNOS, Gp91phox, NFkB and iron positive macrophages (p < 0.05). Although we did not find differences in lung mechanics across all groups, there were low to moderate correlations between inflammation remodeling, oxidative stress and NFkB with elastance, resistance of lung tissue and iron positive macrophages (p < 0.05). Environmental exposure to iron, confirmed by evaluation of iron in alveolar macrophages and in air, exacerbated inflammation, initiated remodeling, and induced oxidative stress responses in exposed mice with and without emphysema. Activation of the iNOS, Gp91phox and NFkB pathways play a role in these changes.


Asunto(s)
Exposición a Riesgos Ambientales , Hierro , Elastasa Pancreática , Animales , Masculino , Ratones , Líquido del Lavado Bronquioalveolar/química , Exposición a Riesgos Ambientales/efectos adversos , Inflamación/metabolismo , Inflamación/inducido químicamente , Hierro/toxicidad , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Elastasa Pancreática/metabolismo , Elastasa Pancreática/farmacología , Polvos/toxicidad
2.
J Appl Toxicol ; 43(6): 887-912, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36598355

RESUMEN

Microorganisms have the potential to produce nutrient-rich products that can be consumed as food or feed. The protein-rich powder derived from heat treatment of the whole-cell biomass of polyhydroxybutyrate-deficient Cupriavidus necator, a metabolically versatile organism that uses elements found in the air, is an example of such a product. To assess the safety of the protein powder for use as a nutritional ingredient in human food, in accordance with internationally accepted standards, its genotoxic potential and repeated-dose oral toxicity were investigated. A bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and an in vivo mammalian micronucleus test were performed. No evidence of mutagenicity or genotoxicity was found. Additionally, a 90-day repeated-dose oral toxicity study in rats was completed, in which a total of 100 male and female Wistar rats were exposed by gavage to daily doses of 1000, 2000, or 3000 mg/kg bw/day of the test material. Following 90 days of continuous exposure, no mortality or treatment-related adverse effects were observed and no target organs were identified. Therefore, a no observed adverse effect level was determined at 3000 mg/kg bw/day, the highest dose tested.


Asunto(s)
Cupriavidus necator , Ratas , Masculino , Humanos , Femenino , Animales , Ratas Wistar , Polvos/toxicidad , Nivel sin Efectos Adversos Observados , Pruebas de Mutagenicidad , Mamíferos
3.
Sci Rep ; 11(1): 21192, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34707144

RESUMEN

Cholesterol oxidation products (COPs) have greater biological activity than cholesterol itself. Oxysterols reduce the nutritional value of foods and exhibit a wide range of biological activity, including pro-oxidant, carcinogenic, and cytotoxic properties. The most commonly detected oxysterols in foods are 7α-HC, 7ß-HC, a product of their dehydrogenation 7-KC and α-CE, ß-CE. The main dietary sources of oxysterols are eggs and egg-derived products, thermally processed milk and milk-based products, fried meat. This study aimed to measure the amount of cholesterol oxidation products in milk powder, egg powder and milk-egg powder during 24 months of storage. The changes in the selected oxysterols (determined by gas chromatography) were recorded. In milk powder, after the production process, the amount of cholesterol was 0.2 g 100 g-1 fat and in egg powder it was 3.4 g 100 g-1. After 6 months of storage, the dominant oxysterol in milk and egg powder was 7α-HC and in milk-egg powder it was 7-KC. After the storage period, oxysterols in powdered milk reached 1.81% of total cholesterol.  The most stable cholesterol was in the milk-egg mixture and its oxidation was the slowest. This study showed the presence of COPs in milk powder, egg powder and milk-egg powder and the effect of storage on cholesterol oxidation.


Asunto(s)
Inocuidad de los Alimentos , Almacenamiento de Alimentos/normas , Oxiesteroles/análisis , Polvos/química , Animales , Huevos/normas , Harina/normas , Almacenamiento de Alimentos/métodos , Leche/normas , Oxiesteroles/toxicidad , Polvos/toxicidad
4.
Inhal Toxicol ; 33(2): 55-65, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33622153

RESUMEN

PURPOSE: Limited number of studies investigated the effects of Electrostatic powder paints (EPP) on human health. We investigated the effects of EPP exposure on lung function, exercise capacity, and quality of life, and the factors determining exercise capacity in EPP workers. METHODS: Fifty-four male EPP workers and 54 age-matched healthy male individuals (control group) were included. Lung function and respiratory muscle strength were measured. The lower limit of normal (LLN) cut-points for FEV1 and FEV1/FVC were calculated. An EPT was used to evaluate bronchial hyperactivity. The handgrip and quadriceps muscle strength were evaluated using a hand-held dynamometer. An ISWT was used to determine exercise capacity. The physical activity level was questioned using the IPAQ. The SGRQ and NHP were used to assessing respiratory specific and general quality of life, respectively. RESULTS: Duration of work, FEV1, MIP, handgrip strength, and ISWT distance were significantly lower, and the change in FEV1 after EPT and %HRmax were significantly higher in the EPP group compared to the control group (p < 0.05). There were no subjects with a < LLN for FEV1 and FEV1/FVC in both groups. In the EPP group, ISWT distance was significantly related to age, height, duration of work, FEV1, change in FEV1 after EPT, MIP, MEP, handgrip strength, IPAQ, SGRQ, and NHP total scores (p < 0.05). The change in FEV1 after EPT, MIP, and duration of work explained % 62 of the variance in the ISWT distance (p < 0.001). CONCLUSIONS: Changes in lung function based on LLN for the FEV1 and FEV1/FVC were not clinically relevant in EPP workers. Exercise capacity is impaired in EPP workers. Degree of exercise-induced bronchospasm, inspiratory muscle strength, and duration of work are the determinants of exercise capacity in EPP workers.


Asunto(s)
Tolerancia al Ejercicio/efectos de los fármacos , Exposición Profesional , Pintura/análisis , Poliésteres/toxicidad , Polvos/toxicidad , Músculos Respiratorios/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Humanos , Masculino , Fuerza Muscular/efectos de los fármacos , Pintura/efectos adversos , Poliésteres/administración & dosificación , Poliésteres/análisis , Polvos/administración & dosificación , Polvos/efectos adversos , Pruebas de Función Respiratoria , Caminata , Adulto Joven
5.
J Sci Food Agric ; 101(4): 1589-1597, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-32869870

RESUMEN

BACKGROUND: Ginkgotoxin including 4'-O-methylpyridoxine (MPN) and MPN-5'-glucoside (MPNG) is responsible for Ginkgo seed food poisoning. The purpose of the work reported was to prepare detoxified Ginkgo seed powder and at the same time to retain the nutritional and functional components of Ginkgo seed powder to the maximum extent. RESULTS: Resin adsorption technology was firstly employed to remove ginkgotoxin from water extract of Ginkgo seed powder. Under optimal conditions, the adsorption efficiency of the optimal resin for MPN could reach 100%, and that for MPNG could only reach 85.4 ± 0.93%. Resin adsorption alone could not effectively remove MPN and MPNG simultaneously. Endogenous enzymatic hydrolysis was next attempted to transform MPNG to MPN. MPNG could be completely hydrolyzed to MPN by endogenous enzyme(s) at 40 °C and pH 5.0 in 180 min. Ginkgotoxin only in the form of MPN in the enzymatic hydrolysate was then adsorbed with resin and the conditions were statistically optimized. The adsorption efficiency of MPN reached 98.89 ± 0.99% under the optimized conditions. CONCLUSIONS: Removal of ginkgotoxin by combining endogenous enzymatic hydrolysis with resin adsorption could preserve the main nutritional and functional components of Ginkgo seed powder to the most extent, and did not change its main characteristics. The ginkgotoxin removal method developed in this work is a relatively simple and efficient approach. © 2020 Society of Chemical Industry.


Asunto(s)
Manipulación de Alimentos/métodos , Ginkgo biloba/química , Proteínas de Plantas/metabolismo , Semillas/toxicidad , Adsorción , Manipulación de Alimentos/instrumentación , Ginkgo biloba/enzimología , Ginkgo biloba/toxicidad , Calor , Hidrólisis , Polvos/química , Polvos/toxicidad , Piridoxina/análogos & derivados , Piridoxina/química , Piridoxina/toxicidad , Resinas Sintéticas/química , Semillas/química
6.
Food Chem ; 338: 127826, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32810815

RESUMEN

This study aimed to evaluate the mutagenicity and oral acute toxicity of winter mushroom powder (PW) treated by atmospheric non-thermal plasma (ANP). Winter mushroom powder without plasma treatment (CW) containing an equivalent amount of sodium nitrite as PW was used as a control. The Ames test revealed that the number of revertant colonies did not significantly increase compared to that in the control. Acute toxicity was assessed in rats that were fed a single dose of winter mushroom powder (5000 mg/kg body weight). Results of the acute toxicity test revealed no remarkable clinical symptoms in any of the rats. No significant difference was observed in of the serum biochemical parameters between the treatments. Regardless of the ANP treatment, mild histological changes were observed in few rats in all groups. Therefore, it is concluded that ANP treatment did not cause any mutagenicity or acute toxicity in the winter mushroom.


Asunto(s)
Flammulina/química , Industria de Procesamiento de Alimentos/métodos , Polvos/toxicidad , Administración Oral , Animales , Masculino , Pruebas de Mutagenicidad , Gases em Plasma , Polvos/administración & dosificación , Polvos/química , Ratas Sprague-Dawley , Pruebas de Toxicidad Aguda
7.
Neurochem Int ; 124: 1-9, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30529642

RESUMEN

Dietary habits are important factors which affect metabolic homeostasis and the development of emotion. We have previously shown that long-term powdered diet feeding in mice increases spontaneous locomotor activity and social interaction (SI) time. Moreover, that diet causes changes in the dopaminergic system, especially increased dopamine turnover and decreased dopamine D4 receptor signals in the frontal cortex. Although the increased SI time indicates low anxiety, the elevated plus maze (EPM) test shows anxiety-related behavior and impulsive behavior. In this study, we investigated whether the powdered diet feeding causes changes in anxiety-related behavior. Mice fed a powdered diet for 17 weeks from weaning were compared with mice fed a standard diet (control). The percentage (%) of open arm time and total number of arm entries were increased in powdered diet-fed mice in the EPM test. We also examined the effects of diazepam, benzodiazepine anti-anxiety drug, bicuculline, GABA-A receptor antagonist, methylphenidate, dopamine transporter (DAT) and noradrenaline transporter (NAT) inhibitor, atomoxetine, selective NAT inhibitor, GBR12909, selective DAT inhibitor, and PD168077, selective dopamine D4 receptor agonist, on the changes of the EPM in powdered diet-fed mice. Methylphenidate and atomoxetine are clinically used to treat attention deficit/hyperactivity disorder (ADHD) symptoms. The % of open arm time in powdered diet-fed mice was decreased by treatments of atomoxetine, methylphenidate and PD168077. Diazepam increased the % of open arm time in control diet-fed mice, but not in powdered diet-fed mice. The powdered diet feeding induced a decrease in GABA transaminase, GABA metabolic enzymes, in the frontal cortex. Moreover, the powdered diet feeding induced an increase in NAT expression, but not DAT expression, in the frontal cortex. These results suggest that the long-term powdered diet feeding may cause low anxiety or impulsivity, possibly via noradrenergic and/or dopaminergic, and GABAAergic mediations and increase the risk for onset of ADHD-like behaviors.


Asunto(s)
Ansiedad/metabolismo , Neuronas Colinérgicas/metabolismo , Conducta Alimentaria/fisiología , Neuronas GABAérgicas/metabolismo , Polvos/toxicidad , Animales , Ansiolíticos/farmacología , Ansiolíticos/uso terapéutico , Ansiedad/inducido químicamente , Ansiedad/psicología , Neuronas Colinérgicas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Conducta Alimentaria/psicología , Neuronas GABAérgicas/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Polvos/administración & dosificación , Factores de Tiempo
8.
J Toxicol Environ Health A ; 81(14): 604-619, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29737961

RESUMEN

Cobalt ferrite nanoparticles (NPs) have received increasing attention due to their widespread therapeutic and agricultural applicability. In the environmental field, dry powder- and ferrofluid-suspended cobalt ferrite NPs were found to be useful for removing heavy metals and metalloids from water, while diluted suspensions of cobalt ferrite NP have been promisingly applied in medicine. However, the potential toxicological implications of widespread exposure are still unknown. Since cobalt ferrite NPs are considered residual wastes of environmental or medical applications, plants may serve as a point-of-entry for engineered nanomaterials as a result of consumption of these plants. Thus, the aim of this study was to assess the effects of dry powder and fresh cobalt ferrite NP on wheat plants. Seven-day assays were conducted, using quartz sand as the plant growth substrate. The toxicity end points measured were seed germination, root and shoot lengths, total cobalt (Co) and iron (Fe) accumulation, photosynthetic pigment production, protein (PRT) production, and activities of catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX). Increasing total Co and Fe in plant tissues indicated that wheat plants were exposed to cobalt ferrite NP. Seed germination and shoot length were not sufficiently sensitive toxicity end points. The effective concentration (EC50) that diminished root length of plants by 50% was 1963 mg/kg for fresh ferrite NPs and 5023 mg/kg for powder ferrite NP. Hence, fresh ferrite NPs were more toxic than powder NP. Plant stress was indicated by a significant decrease in photosynthetic pigments. CAT, APX, and GPX antioxidant enzymatic activity suggested the generation of reactive oxygen species and oxidative damage induced by cobalt ferrite NP. More studies are thus necessary to determine whether the benefits of using these NPs outweigh the risks.


Asunto(s)
Cobalto/toxicidad , Compuestos Férricos/toxicidad , Estrés Oxidativo , Fotosíntesis/efectos de los fármacos , Triticum/efectos de los fármacos , Antioxidantes/metabolismo , Cobalto/química , Compuestos Férricos/química , Germinación/efectos de los fármacos , Nanopartículas del Metal , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/biosíntesis , Polvos/química , Polvos/toxicidad , Plantones/crecimiento & desarrollo , Semillas/efectos de los fármacos , Semillas/enzimología , Semillas/crecimiento & desarrollo , Semillas/fisiología , Pruebas de Toxicidad , Triticum/enzimología , Triticum/crecimiento & desarrollo , Triticum/fisiología
9.
Toxicol Ind Health ; 34(7): 449-457, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29669483

RESUMEN

The objective of this study was to assess the lung toxicity induced by the inhalation of different hard metal constituents and silica powder and screen for potential toxicity biomarkers. Rats were randomly divided into saline, cobalt, tungsten carbide, silica, and hard metal (HM) groups and were administered a single 10-mg dose of the respective treatments. After 8 weeks, the lung tissue structure in the HM group was deformed, numerous nucleated giant and epithelial-like cells appeared in the stroma, and the computed tomography scanning images appeared abnormal. Krebs von den Lungen-6 (KL-6), transforming growth factor (TGF)-ß1, and TGF-ß2 expression in bronchoalveolar lavage fluid (BALF) significantly differed between the groups ( p < 0.05). Serum KL-6 and TGF-ß1, but not TGF-ß2, levels significantly differed between some groups ( p < 0.05). We observed multinucleated giant cells in the rat lung tissue. While the serum and BALF levels of KL-6 and TGF-ß2 are not highly specific, TGF-ß1 may be a valuable reference diagnostic marker in HM lung disease.


Asunto(s)
Pulmón , Metales Pesados/toxicidad , Dióxido de Silicio/toxicidad , Animales , Femenino , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/patología , Mucina-1/metabolismo , Polvos/toxicidad , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta1/metabolismo
10.
Int J Med Mushrooms ; 20(12): 1185-1195, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30806299

RESUMEN

A compositional study was performed on fruiting-body powder of the culinary-medicinal oyster mushroom Pleurotus ostreatus for applications as a nutraceutical/functional food. Carbohydrates (55 g/100 g dry weight [dw]) and proteins (27.45 g/100 g dw, with an in vitro digestibility of 75%) appear to be the major components, but fat content was low (4 g/100 g dw). Pleurotus powder has important micronutrients such as minerals (Fe, Cu, Zn, Mn, Mg, and Co) and ascorbic acid, as well as nonnutrients (i.e., phenolics) with antioxidant potential. A powder-derived aqueous extract had a phenolic compound content of 138 mg/100 g that showed 2,2-diphenyl-1-picrylhydrazyl radical scavenging and inhibition of membrane-lipid peroxidation activities of 58.3% and 61.4%, respectively. The presence of ß-1,3-1,6-D-glucans was also demonstrated (1.54 g/100 g). An acute toxicity test proved that Pleurotus powder was safe after oral administration to both male and female mice at a dose of 2000 mg/kg. The combination of rich nutritional composition, bioactivity, and safety in P. ostreatus fruiting-body powder highlights its potential as a nutraceutical agent promoting health and life quality.


Asunto(s)
Antioxidantes/química , Suplementos Dietéticos/análisis , Pleurotus/química , Animales , Antioxidantes/toxicidad , Suplementos Dietéticos/toxicidad , Femenino , Cuerpos Fructíferos de los Hongos/química , Masculino , Ratones , Ratones Endogámicos BALB C , Minerales/análisis , Polvos/química , Polvos/toxicidad
11.
Food Chem Toxicol ; 103: 86-101, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28223121

RESUMEN

TruActive™ NF is a novel, fat-free, milk-based protein powder to be added to food to increase protein content and is manufactured using non-thermal treatment to reduce potential pathogens most relevant to protecting public health. TruActive™ NF was evaluated for potential pathogens of concern to public health regulators; none were detected. The estimated daily intake (EDI) of TruActive™ NF at a 90th percentile consumption for the powder in nutritional beverages and bars is 14,700 mg/day. In vitro genotoxicity testing revealed that concentrations of TruActive™ NF up to 5000 µg/plate did not induce point mutations in selected strains. Oral administration of TruActive™ NF to male Sprague-Dawley rats in an in vivo mammalian chromosomal aberration assay did not induce chromosomal aberrations or significantly affect mitosis in bone marrow cells at 2000 mg/kg. Male and female Sprague-Dawley rats were administered TruActive™ NF at concentrations of 7.5%, 15%, and 30% of the diet during a 28-day subacute dietary study followed by a 14-day recovery period. Some parameters were altered at the 30% diet concentration. The No Observed Adverse Effect Level (NOAEL) in the 28-day dietary study was at 15% of the diet (11,812 mg/kg bw/day for male rats and 11,521 mg/kg bw/day for female rats).


Asunto(s)
Manipulación de Alimentos/métodos , Proteínas de la Leche/toxicidad , Pruebas de Toxicidad/métodos , Animales , Aberraciones Cromosómicas , Dieta , Femenino , Masculino , Proteínas de la Leche/análisis , Proteínas de la Leche/química , Pruebas de Mutagenicidad , Nivel sin Efectos Adversos Observados , Polvos/toxicidad , Ratas Sprague-Dawley
12.
Risk Anal ; 37(5): 918-929, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27393372

RESUMEN

This study's objective is to assess the risk of asbestos-related disease being contracted by past users of cosmetic talcum powder.  To our knowledge, no risk assessment studies using exposure data from historical exposures or chamber simulations have been published. We conducted activity-based sampling with cosmetic talcum powder samples from five opened and previously used containers that are believed to have been first manufactured and sold in the 1960s and 1970s.  These samples had been subject to conflicting claims of asbestos content; samples with the highest claimed asbestos content were tested.  The tests were conducted in simulated-bathroom controlled chambers with volunteers who were talc users.  Air sampling filters were prepared by direct preparation techniques and analyzed by phase contrast microscopy (PCM), transmission electron microscopy (TEM) with energy-dispersive x-ray (EDX) spectra, and selective area diffraction (SAED).  TEM analysis for asbestos resulted in no confirmed asbestos fibers and only a single fiber classified as "ambiguous."  Hypothetical treatment of this fiber as if it were asbestos yields a risk of 9.6 × 10-7 (under one in one million) for a lifetime user of this cosmetic talcum powder.  The exposure levels associated with these results range from zero to levels far below those identified in the epidemiology literature as posing a risk for asbestos-related disease, and substantially below published historical environmental background levels.  The approaches used for this study have potential application to exposure evaluations of other talc or asbestos-containing materials and consumer products.


Asunto(s)
Cosméticos/toxicidad , Polvos/toxicidad , Medición de Riesgo/métodos , Talco/toxicidad , Aire , Amianto/análisis , Cosméticos/análisis , Humanos , Exposición por Inhalación/análisis , Microscopía Electrónica de Transmisión , Microscopía de Contraste de Fase , Fibras Minerales/análisis , Fibras Minerales/toxicidad , Exposición Profesional , Polvos/análisis , Probabilidad , Respiración , Talco/análisis , Termogravimetría , Rayos X
13.
Rev Environ Health ; 31(4): 401-407, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27837598

RESUMEN

In climbing halls, high levels of dust are found because magnesia powder is used to dry hands. Concerns have been raised about possible health effects after reports from asthmatics experiencing worsening of symptoms while or after climbing. We investigated acute and sub-acute effects of climbing in dusty halls on lung function in two pilot studies. The first study examined 109 climbers before and after a climbing activity that lasted at least 1 h. In the second study, 25 climbers from different age classes participated in a 2-day climbing competition. Of these, 24 agreed to take part in our investigation, but only 22 provided valid lung function tests on both days. The climbers underwent lung function tests before the first round of the competition (in the morning), after the second round approximately 3 h later and in the morning of the second day before the competition started again. In the first study, we found acute effects, a decline in lung function immediately after the exposure, likely due to protective reflexes of the bronchial muscles and stronger declines in persons with higher exhaled nitric oxide (NO) pre-climbing. In the second study, we also expected sub-acute effects on the next day due to inflammation. On the first day of the competition (second study), dust levels at a central monitor increased over time in a linear manner. Most of the dust was in the size range between 2.5 and 10 µm and dust levels of particulate matter (PM10) reached 0.5 mg/m3. There was a decline in lung function over 24 h in persons with higher exhaled NO levels pre-exposure. All spirometric parameters were affected though the effects were not statistically significant in all cases. Younger age classes started earlier in the morning. Because of the increasing trend in dust levels we expected stronger effects with higher numbers but for the acute effects the reverse was true, possibly because younger climbers use magnesia more or with less experience thus causing higher individual exposure. No differences by age or by time of the first climb were observed for the 24-h lung function change.


Asunto(s)
Contaminación del Aire Interior/análisis , Polvo/análisis , Exposición a Riesgos Ambientales , Ejercicio Físico , Material Particulado/toxicidad , Polvos/toxicidad , Adulto , Humanos , Óxido de Magnesio/química , Montañismo , Tamaño de la Partícula , Proyectos Piloto , Pruebas de Función Respiratoria , Adulto Joven
14.
Biomed Res Int ; 2016: 7183951, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28042571

RESUMEN

This study selected solid wastes, such as rice husk ash (RHA), inactive Saccharomyces cerevisiae powder (ISP), and rice husk (RH), as the potential adsorbents for the removal of Fe(II) and Mn(II) in aqueous solution. The structural characteristics, functional groups, and elemental compositions were determined by scanning electron microscope (SEM) and Fourier translation infrared spectrum (FT-IR) analyses, respectively. Then the influence on the Fe(II) and Mn(II) removing efficiency by the factors, such as pH, adsorbent dosage, initial Fe(II) and Mn(II) concentration, and contact time, was investigated by the static batch test. The adsorption isotherm study results show that Langmuir equation can better fit the Fe(II) and Mn(II) adsorption process by the three adsorbents. The maximum adsorption amounts for Fe(II) were 6.211 mg/g, 4.464 mg/g, and 4.049 mg/g by RHA, ISP, and RH and for Mn(II) were 3.016 mg/g, 2.229 mg/g, and 1.889 mg/g, respectively. The adsorption kinetics results show that the pseudo-second-order kinetic model can better fit the Fe(II) and Mn(II) adsorption process. D-R model and thermodynamic parameters hint that the adsorption processes of Fe(II) and Mn(II) on the three adsorbents took place physically and the processes were feasible, spontaneous, and exothermic.


Asunto(s)
Compuestos Ferrosos/química , Manganeso/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Adsorción , Compuestos Ferrosos/toxicidad , Manganeso/toxicidad , Oryza/química , Polvos/química , Polvos/toxicidad , Saccharomyces cerevisiae/química , Residuos Sólidos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad
15.
BMC Pharmacol Toxicol ; 16: 29, 2015 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-26502880

RESUMEN

BACKGROUND: Glucagon nasal powder (GNP), a novel intranasal formulation of glucagon being developed to treat insulin-induced severe hypoglycemia, contains synthetic glucagon (10% w/w), beta-cyclodextrin, and dodecylphosphocholine. The safety of this formulation was evaluated in four studies in animal models. METHODS: The first study evaluated 28-day sub-chronic toxicology in rats treated intranasally with 1 and 2 mg of GNP/day (0.1 and 0.2 mg glucagon/rat/day). The second study evaluated 28-day sub-chronic toxicology in dogs administered 20 and 40 mg of formulation/dog/day (2 and 4 mg glucagon/dog/day) intranasally. A pulmonary insufflation study assessed acute toxicology following intra-tracheal administration of 0.5 mg of GNP (0.05 mg glucagon) to rats. Local tolerance to 30 mg of GNP (equivalent to 3 mg glucagon, the final dose for humans) was tested through direct administration into the eyes of rabbits. RESULTS: There were no test article-related adverse effects on body weight and/or food consumption, ophthalmology, electrocardiography, hematology, coagulation parameters, clinical chemistry, urinalysis, or organ weights, and no macroscopic findings at necropsy in any study. In rats, direct intra-tracheal insufflation at a dose of 0.5 mg of GNP/rat (0.05 mg glucagon/rat) did not result in adverse clinical, macroscopic, or microscopic effects. In dogs, the only adverse findings following sub-chronic use were transient (<30 s) salivation and sneezing immediately post-treatment and mild to moderate reversible histological changes to the nasal mucosa. Daily dosing over 28 days in rats resulted in mild to moderate, unilateral or bilateral erosion/ulceration of the olfactory epithelium, frequently with minimal to mild, acute to sub-acute inflammation of the lamina propria at the dorsal turbinates of the nasal cavity in 2/10 males and 3/10 females in the high-dose group (0.2 mg glucagon/day). These lesions resolved completely over 14 days. Histological examination of tissues from both sub-chronic studies in dogs and rats revealed no microscopic findings. In rabbits, clinical observations noted in the GNP-treated eye and/or surrounding areas included ≥1 of the following: clear discharge, red conjunctiva, partial closure, and swelling of the peri-orbital area, which correlated with erythema and edema noted during ocular observations and grading. DISCUSSION: The studies reported here revealed no safety concerns associated with GNP in animal models. Studies published earlier have highlighted the local safety profile of intranasally administered cyclodextrins (a component of GNP). The choline group, the phosphate group, and the saturated 12-carbon aliphatic chain that are present in the dodecylphosphocholine excipient used in GNP are all present in the phospholipids and lecithins seen ubiquitously in mammalian cell membranes and are unlikely to pose safety concerns; this notion is supported by several studies conducted by the authors that revealed no safety concerns. Taken together, these results suggest that intranasal delivery of GNP holds promise as a future rescue medication for use by caregivers to treat insulin-induced hypoglycemic episodes in patients with type 1 or type 2 diabetes. CONCLUSION: This novel drug product is well tolerated in animal models.


Asunto(s)
Glucagón/toxicidad , Fosforilcolina/análogos & derivados , Polvos/toxicidad , beta-Ciclodextrinas/toxicidad , Administración Intranasal , Animales , Área Bajo la Curva , Peso Corporal/efectos de los fármacos , Perros , Femenino , Glucagón/administración & dosificación , Glucagón/farmacocinética , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Tasa de Depuración Metabólica , Modelos Animales , Tamaño de los Órganos/efectos de los fármacos , Fosforilcolina/administración & dosificación , Fosforilcolina/farmacocinética , Fosforilcolina/toxicidad , Polvos/administración & dosificación , Polvos/farmacocinética , Conejos , Ratas Sprague-Dawley , Especificidad de la Especie , Análisis de Supervivencia , Factores de Tiempo , Pruebas de Toxicidad/métodos , beta-Ciclodextrinas/administración & dosificación , beta-Ciclodextrinas/farmacocinética
17.
Ind Health ; 53(1): 56-68, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25327299

RESUMEN

A new approach to assess the risks inherent in the implementation of powders, including nanomaterials, has been developed, based on the OHB (Occupational Hazard Band) method which is widely spread in the chemical industry. Hazard classification has not been modified; only the control of exposure has been worked at. The method applies essentially to the prevention of the exposures to airborne materials, whatever their particle size. The method considers exposure based on seven parameters which take into account the characteristics of the materials used, their emission potential, the conditions of use, as well as classic parameters of exposure characterization like duration and frequency. The method is a pragmatic exploitation of the state-of-art and of available data, bearing in mind that a lot of them are not easily accessible to factory operators. The result of the reflection is then positioned on a hazard versus exposure matrix from which 4 levels of priority of action are defined, as in the classical OHB method used to manage pure chemical risk. This approach fills a gap in terms of risk assessment and avoids jeopardizing all that has been set up for years, while introducing new elements of decision making accessible to all operators.


Asunto(s)
Nanoestructuras , Exposición Profesional/efectos adversos , Salud Laboral , Polvos , Humanos , Nanoestructuras/toxicidad , Polvos/toxicidad , Medición de Riesgo/métodos
18.
J Toxicol Environ Health A ; 77(22-24): 1319-31, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25343283

RESUMEN

Aloe has been used in versatile herbal medications and nutraceuticals throughout history. Aloe is widely considered to be generally safe for humans and used globally. The effectiveness and pharmacological properties of aloe are dependent upon when the plant is collected. However, little is known about the toxicology of whole-body aloe collected within less than 1 yr. Based upon widespread exposure to aloe, it is important to determine a daily intake level of this chemical to ensure its safety for humans. To determine the no-observed-adverse-effect level (NOAEL) of baby aloe powder (BAP) for clinical application, Sprague-Dawley (SD) rats were treated orally for 4 wk with 4 different concentrations: 0, 0.125, 0.5, and 2 g/kg body weight (bw). In this study, no significant or dose-dependent toxicological effects of BAP were observed in biochemical or hematological parameters, urinalysis, clinical signs, body weight, and food and water consumption. There were changes in some biomarkers in certain treated groups compared to controls; however, all values were within their reference ranges and not dose-dependent. Based on these results, the NOAEL of BAP was estimated to be greater than 2 g/kg bw in male and 2 g/kg bw in female SD rats. Collectively, these data suggest that BAP used in this study did not produce any marked subacute toxic effects up to a maximum concentration of 2 g/kg bw, and thus use in nutraceuticals and in pharmaceutical and cosmetic applications at a concentration of >2 g/kg is warranted.


Asunto(s)
Aloe/química , Suplementos Dietéticos/toxicidad , Preparaciones de Plantas/administración & dosificación , Preparaciones de Plantas/toxicidad , Animales , Peso Corporal , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/fisiología , Polvos/toxicidad , Ratas , Ratas Sprague-Dawley , Urinálisis
19.
Int J Nanomedicine ; 8: 2871-85, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23990716

RESUMEN

Excipients having self-assembling properties are less explored in the field of dry powder inhalation (DPI) technology. An amphiphilic lipopolymer system was developed using stearic acid (SA) and branched polyethyleneimine (BPEI) (1800 Dalton), at different proportions by covalent conjugation. A molecular dynamic (MD) simulation tool was employed for predicting the carrier behavior in a polar in vivo condition. The structural characterization was carried out using nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared (FTIR) spectroscopy. The physical nature of the lipopolymer was analyzed by differential scanning calorimetry. Determination of zeta potential and diameter of the micelles showed existence of cationic particles in the nano size range when a lower number of primary amino groups of BPEI was grafted with SA. The rifampicin (RIF)-loaded lipopolymer was also formulated further into spray-dried microparticles. Powder X-ray diffraction (PXRD) studies revealed that the RIF API (active pharmaceutical ingredient) exists as molecular dispersion in spray-dried microparticles. Topological analysis of the spray-dried nanomicelle was carried out using scanning electron microscopy (SEM). A large population of the drug-carrying particles were found to be under the inhalable size range (fine particle fraction 67.88% ± 3%). In vitro drug release kinetics from spray-dried nanomicelles were carried out at lung fluid pH.


Asunto(s)
Antituberculosos/farmacocinética , Portadores de Fármacos/química , Nanopartículas/química , Polvos/farmacocinética , Rifampin/farmacocinética , Antituberculosos/química , Antituberculosos/toxicidad , Cationes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidad , Humanos , Macrófagos/química , Macrófagos/metabolismo , Macrófagos/microbiología , Microscopía Confocal , Simulación de Dinámica Molecular , Mycobacterium smegmatis/química , Mycobacterium smegmatis/metabolismo , Nanopartículas/toxicidad , Polietileneimina/química , Polvos/química , Polvos/toxicidad , Rifampin/química , Rifampin/toxicidad , Ácidos Esteáricos/química
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