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1.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142207

RESUMO

Chronic kidney disease (CKD) is characterized as sustained damage to the renal parenchyma, leading to impaired renal functions and gradually progressing to end-stage renal disease (ESRD). Diabetes mellitus (DM) and arterial hypertension (AH) are underlying diseases of CKD. Genetic background, lifestyle, and xenobiotic exposures can favor CKD onset and trigger its underlying diseases. Cigarette smoking (CS) is a known modified risk factor for CKD. Compounds from tobacco combustion act through multi-mediated mechanisms that impair renal function. Electronic nicotine delivery systems (ENDS) consumption, such as e-cigarettes and heated tobacco devices, is growing worldwide. ENDS release mainly nicotine, humectants, and flavorings, which generate several byproducts when heated, including volatile organic compounds and ultrafine particles. The toxicity assessment of these products is emerging in human and experimental studies, but data are yet incipient to achieve truthful conclusions about their safety. To build up the knowledge about the effect of currently employed ENDS on the pathogenesis of CKD, cellular and molecular mechanisms of ENDS xenobiotic on DM, AH, and kidney functions were reviewed. Unraveling the toxic mechanisms of action and endpoints of ENDS exposures will contribute to the risk assessment and implementation of proper health and regulatory interventions.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Insuficiência Renal Crônica , Produtos do Tabaco , Compostos Orgânicos Voláteis , Humanos , Higroscópicos , Nicotina/efeitos adversos , Material Particulado , Insuficiência Renal Crônica/induzido quimicamente , Tabaco/efeitos adversos , Xenobióticos/toxicidade
2.
Int J Toxicol ; 41(3_suppl): 77-128, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36177798

RESUMO

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of Panthenol, Pantothenic Acid, and 5 derivatives as used in cosmetics. These ingredients named in this report are reported to function in cosmetics as hair conditioning agents, and Panthenol also is reported to function as a skin-conditioning agent-humectant and a solvent. The Panel reviewed relevant data for these ingredients, and concluded that these 7 ingredients are safe in cosmetics in the present practices of use concentration described in this safety assessment.


Assuntos
Qualidade de Produtos para o Consumidor , Cosméticos , Cosméticos/toxicidade , Higroscópicos , Ácido Pantotênico/análogos & derivados , Ácido Pantotênico/toxicidade , Medição de Risco , Solventes
3.
Int J Toxicol ; 41(3_suppl): 69-76, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35993419

RESUMO

The Expert Panel for Cosmetic Ingredient Safety (Panel) re-reviewed the safety of Malic Acid and Sodium Malate in cosmetics. Malic Acid is reported to function in cosmetics as a fragrance ingredient and a pH adjuster and Sodium Malate functions as a skin-conditioning agent - humectant. The Panel reviewed the available data to determine the safety of these ingredients. The Panel concluded that Malic Acid and Sodium Malate are safe in cosmetics in the present practices of use and concentration described in this safety assessment.


Assuntos
Cosméticos , Malatos , Qualidade de Produtos para o Consumidor , Cosméticos/toxicidade , Higroscópicos , Malatos/toxicidade , Medição de Risco , Sódio
4.
Molecules ; 27(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35956965

RESUMO

Porous carbohydrate materials such as tobacco shreds readily absorb moisture and become damp during processing, storage, and consumption (smoking). Traditional humectants have the ability of moisture retention but moisture-proofing is poor. Polygonatum cyrtonema Hua polysaccharide (PCP 85-1-1) was separated by fractional precipitation and was purified by anion exchange and gel permeation chromatography. The average molecular weight (Mw) of PCP 85-1-1 was 2.88 × 103 Da. The monosaccharide composition implied that PCP 85-1-1 consisted of fucose, glucose, and fructose, and the molar ratio was 22.73:33.63:43.65. When 2% PCP 85-1-1 was added to tobacco shreds, the ability of moisture retention and moisture-proofing were significantly enhanced. The moisture retention index (MRI) and moisture-proofing index (MPI) increased from 1.95 and 1.67 to 2.11 and 2.14, respectively. Additionally, the effects of PCP 85-1-1 on the aroma and taste of tobacco shreds were evaluated by electronic tongue and gas chromatography-mass spectrometry (GC-MS). These results indicated that PCP 85-1-1 had the characteristics of preventing water absorption under high relative humidity and moisturizing under dry conditions. The problem that traditional humectants are poorly moisture-proof was solved. PCP 85-1-1 can be utilized as a natural humectant on porous carbohydrates, which provides a reference for its development and utilization.


Assuntos
Polygonatum , Carboidratos da Dieta , Higroscópicos , Polygonatum/química , Polissacarídeos/química , Porosidade
5.
J Environ Sci Health B ; 57(9): 710-719, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35861133

RESUMO

The objective of this study was to evaluate the use of diquat, glufosinate ammonium, saflufenacil and flumioxazim, positioned alone and/or combined, in the pre-harvest desiccation of soybean crops. For this purpose, a field experiment was conducted, with application of the treatments in the phenological stage R 7.2 of soybean. At 3 DAA, the herbicides diquat and their combinations with flumioxazin and ammonium glufosinate, at all doses, resulted in defoliation and desiccation percentages greater than 90%. At 5 DAA, only the flumioxazin and glufosinate ammonium treatments, alone, did not show indices for harvesting. At 10 DAA, only the control differed from the other treatments in relation to desiccation, demonstrating the need to apply desiccants to enable harvest. The results indicate that the combination of herbicides may represent an alternative to reduce doses and increase the efficacy of isolated products through synergism, in addition to operational gains.


Assuntos
Herbicidas , Paraquat , Aminobutiratos , Antivirais , Benzoxazinas , Dessecação , Diquat , Herbicidas/análise , Herbicidas/farmacologia , Higroscópicos , Ftalimidas , Soja
6.
Sci Rep ; 12(1): 10232, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715536

RESUMO

Various methods of evaluating a humectant's moisture retention have unique mechanisms. Hence, for designing advanced or efficient ingredients of cosmetic products, a clear understanding of differences among methods is required. The aim of this study was to analyze the moisture-retention capacity of glycerin, a common ingredient in cosmetic products. Specifically, this study applied gravimetric analysis, transepidermal water loss (TEWL) analysis, and differential scanning calorimetry (DSC) to examine the evaporation of glycerin solutions of different concentrations. The results revealed that the moisture-retention capacity of glycerin increased with the glycerin concentration from 0 to 60 wt%, and glycerin at concentration of 60-70 wt% did not exhibit weight change during the evaporation process. When the glycerin concentration exceeded 70 wt%, moisture sorption occurred in the glycerin solution. Furthermore, the results revealed a deviation between the evaporation rates measured using gravimetric analysis and those measured using TEWL analysis. However, normalizing the results of these analyses yielded the relative evaporation rates to water, which were consistent between these two analyses. DSC thermograms further confirmed the consistent results and identified two hydrated water microstructures (nonfreezable water and free water) in the glycerin solutions, which explained why the measured evaporation rate decreased with the glycerin concentration. These findings can be applied to prove the moisture-retention capacity of a humectant in cosmetic products by different measuring methods.


Assuntos
Cosméticos , Glicerol , Varredura Diferencial de Calorimetria , Cosméticos/análise , Glicerol/química , Higroscópicos , Água/química
7.
J Sci Food Agric ; 102(14): 6727-6736, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35622938

RESUMO

BACKGROUND: Salad dressing formulations include a pH within 3.2-4.1, salt and other solutes to depress water activity. The interaction between hydrocolloids and other components such as humectants determines their physical and microbiological stability. To our knowledge, the effect of commonly used solutes on physical stability and rheological characteristics of oil-in-water emulsions stabilized by xanthan gum has not been reported, and neither has the effect of a spoilage yeast on physical stability been evaluated. RESULTS: The effect of different humectants (sodium chloride, glucose and xylitol) and Zygosaccharomyces bailii inoculation on the stability of oil-in-water emulsions containing different levels of xanthan gum to emulate different types of salad dressings was investigated by means of droplet size, zeta potential, rheological measurements and confocal laser scanning microscopy (CLSM). Generally, the addition of humectants strengthened the weak or strong emulsion structure, especially xylitol. Glucose or xylitol acted as stabilizers since they decreased Sauter and De Broucker diameter. On the contrary, NaCl destabilized the emulsions since it increased droplet size and exhibited the lowest absolute values of zeta potential. Inoculation with Z. bailii destabilized some emulsions since it increased Sauter and De Broucker diameter. Emulsion droplet size, polydispersity, and xanthan gum and yeast location were confirmed by CLSM imaging. CONCLUSION: This study highlights the key role of humectants and xanthan gum level on physical characteristics and stability of oil-in-water emulsions. Addition of xylitol leads to an enhancement in emulsion rheology and physical stability, suggesting that it is a potential low-calorie multifunctional additive for salad dressings. © 2022 Society of Chemical Industry.


Assuntos
Higroscópicos , Cloreto de Sódio , Condimentos , Emulsões/química , Glucose , Reologia , Saccharomyces cerevisiae , Saccharomycetales , Soluções , Água/química , Xilitol
8.
Front Public Health ; 10: 782068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372219

RESUMO

Electronic cigarette, or vaping, products are used to heat an e-liquid to form an aerosol (liquid droplets suspended in gas) that the user inhales; a portion of this aerosol deposits in their respiratory tract and the remainder is exhaled, thereby potentially creating opportunity for secondhand exposure to bystanders (e.g., in homes, automobiles, and workplaces). Particle size, a critical factor in respiratory deposition (and therefore potential for secondhand exposure), could be influenced by e-liquid composition. Hence, the purposes of this study were to (1) test the influence of laboratory-prepared e-liquid composition [ratio of propylene glycol (PG) to vegetable glycerin (VG) humectants, nicotine, and flavorings] on particle size distribution and (2) model respiratory dosimetry. All e-liquids were aerosolized using a second-generation reference e-cigarette. We measured particle size distribution based on mass using a low-flow cascade impactor (LFCI) and size distribution based on number using real-time mobility sizers. Mass median aerodynamic diameters (MMADs) of aerosol from e-liquids that contained only humectants were significantly larger compared with e-liquids that contained flavorings or nicotine (p = 0.005). Humectant ratio significantly influenced MMADs; all aerosols from e-liquids prepared with 70:30 PG:VG were significantly larger compared with e-liquids prepared with 30:70 PG:VG (p = 0.017). In contrast to the LFCI approach, the high dilution and sampling flow rate of a fast mobility particle sizer strongly influenced particle size measurements (i.e., all calculated MMAD values were < 75 nm). Dosimetry modeling using LFCI data indicated that a portion of inhaled particles will deposit throughout the respiratory tract, though statistical differences in aerosol MMADs among e-liquid formulations did not translate into large differences in deposition estimates. A portion of inhaled aerosol will be exhaled and could be a source for secondhand exposure. Use of laboratory-prepared e-liquids and a reference e-cigarette to standardize aerosol generation and a LFCI to measure particle size distribution without dilution represents an improved method to characterize physical properties of volatile aerosol particles and permitted determination of MMAD values more representative of e-cigarette aerosol in situ, which in turn, can help to improve dose modeling for users and bystanders.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Fenômenos Fisiológicos Respiratórios , Aerossóis , Aromatizantes , Humanos , Higroscópicos , Nicotina , Tamanho da Partícula , Sistema Respiratório
9.
AAPS J ; 24(3): 52, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35384529

RESUMO

In-clinic dried blood spot (DBS) pharmacokinetic (PK) sampling was incorporated into two phase 3 studies of verubecestat for Alzheimer's disease (EPOCH [NCT01739348] and APECS [NCT01953601]), as a potential alternative to plasma PK sampling for improved logistical feasibility and decreased blood volume burden. However, an interim PK analysis revealed verubecestat concentrations in DBS samples declined with time to assay in both trials. An investigation revealed wide variation in implementation practices for DBS sample handling procedures resulting in insufficient desiccation which caused verubecestat instability. High-resolution mass spectrometry evaluations of stressed and aged verubecestat DBS samples revealed the presence of two hydrolysis degradants. To minimize instability, new DBS handling procedures were implemented that provided additional desiccant and minimized the time to analysis. Both verubecestat hydrolysis products were previously discovered and synthesized during active pharmaceutical ingredient stability characterization. A liquid chromatography-mass spectrometry assay to quantitate the dominant verubecestat degradant in DBS samples was developed and validated. The application of this method to stressed and aged verubecestat DBS samples confirmed that degradant concentrations accounted for the observed decreases in the verubecestat concentration. Furthermore, after increasing desiccant amounts, degradant concentrations accounted for approximately 7% of the verubecestat concentration in DBS clinical samples, indicating that issues with sample handling were minimized with new storage and shipping conditions. This case study illustrates the challenges with employing new sampling techniques in large, global trials, and the importance of anticipating and mitigating implementation risks.


Assuntos
Teste em Amostras de Sangue Seco , Espectrometria de Massas em Tandem , Óxidos S-Cíclicos , Teste em Amostras de Sangue Seco/métodos , Higroscópicos , Manejo de Espécimes , Espectrometria de Massas em Tandem/métodos , Tiadiazinas
10.
Sci Total Environ ; 825: 153966, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35183644

RESUMO

Atmospheric water harvesting (AWH) is an emerging technology for decentralized water supply and is proving to be viable for use in emergencies, military deployment, and sustainable industries. The atmosphere is a freshwater reservoir that contains 12,900 km3 of water, 6-fold more than the volume of global rivers. Dehumidification water harvesting technologies can be powered by solar, wind, or electric sources. Compressor/refrigerant-based dehumidifiers operate via dew point condensation and provide a cold surface upon which water vapor can condense. Conversely, desiccant-based technologies saturate water vapor using a sorbent that is then heated, and the supersaturated water vapor condenses on a surface when interacting with cooler ambient process air. This work compares productivity, energy consumption, efficiency, cost and quality of water produced of two water-harvesting mechanisms. Electric-powered compressor and desiccant dehumidifiers were operated outdoors for more than one year in the arid southwestern USA, where temperatures ranged from 3.1 to 43.7 °C and relative humidity (RH) ranged from 6 to 85%. The compressor system harvested >2-fold more water than the desiccant system when average RH during the run cycle was >30%, average temperature was >20 °C, and average dew point temperature was >5 °C. Desiccant systems performed more favorably when average RH during the run cycle was <30%, average temperature was <20 °C, and average dew point temperature was <5 °C. Water collected by compressor-based technologies had conductivity up to 180 µS/cm, turbidity up to 190 NTU, and aluminum, iron and manganese near or above the US EPA secondary drinking water standard. Dissolved organic carbon (DOC) averaged <2 mg C/L but ranged up to 12 mg C/L. Water collected by desiccant-based technologies had significantly lower conductivity, metals, and turbidity, and DOC was always <6 mg/L. Aldehydes such as formaldehyde and acetaldehyde and carboxylic acids such as formic acid and acetic acid were primary contributors to DOC. The differences in harvested water quality were attributed to differences in the condensation method between compressor and desiccant AWH technologies. Multiple strategies could be employed to prevent these volatile organic compounds (VOCs) from contributing to DOC in harvested water, such as pretreating air to remove VOCs or post-treating DOC in harvested liquid water.


Assuntos
Higroscópicos , Compostos Orgânicos Voláteis , Atmosfera , Estações do Ano , Vapor , Qualidade da Água
11.
Angew Chem Int Ed Engl ; 61(12): e202115821, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35044711

RESUMO

The first enantioselective synthesis of α-allenylic amides and ketones through allenylic alkylation of vinyl azides is reported. In these chemodivergent reactions, cooperatively catalyzed by a IrI /(phosphoramidite,olefin) complex and Sc(OTf)3 , vinyl azides act as the surrogate for both amide enolates and ketone enolates. The desiccant (molecular sieves) plays a crucial role in controlling the chemodivergency of this enantioconvergent and regioselective reaction: Under otherwise identical reaction conditions, the presence of the desiccant led to α-allenylic amides, while its absence resulted in α-allenylic ketones. Utilizing racemic allenylic alcohols as the alkylating agent, the overall process represents a dynamic kinetic asymmetric transformation (DyKAT), where both the products are formed with the same absolute configuration. To the best of our knowledge, this is the first example of the use of vinyl azide as the ketone enolate surrogate in an enantioselective transformation.


Assuntos
Irídio , Cetonas , Alquilação , Amidas , Azidas , Ácidos Carboxílicos , Catálise , Higroscópicos , Estereoisomerismo
12.
Tob Control ; 31(4): 527-533, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33408120

RESUMO

INTRODUCTION: Flavourants and humectants in waterpipe tobacco (WT) increase product appeal. Removal of these constituents, however, is associated with increased intensity of WT puffing, likely due to reduced nicotine delivery efficiency. To clarify the potential public health outcomes of restrictions on flavourants or humectants in WT, we evaluated the effects of these constituents on puffing behaviours, biomarkers of exposure and subjective effects among adults with high versus low WT dependence. METHODS: N=39 high dependence and N=49 low dependence WT smokers (Lebanese Waterpipe Dependence Scale scores >10 = high dependence) completed four smoking sessions in a cross-over experiment. Conditions were preferred flavour with humectant (+F+H), preferred flavour without humectant (+F-H), unflavoured with humectant (-F+H) and unflavoured without humectant (-F-H). Measures of puff topography, plasma nicotine and expired carbon monoxide (eCO) boost, and subjective effects were assessed. RESULTS: Level of WT dependence modified the effect of WT condition on average flow rate, average puff volume and eCO boost. Although, overall, participants puffed the +F+H WT least intensely and -F-H WT most intensely, this association was strongest among WT smokers with high dependence. Participants preferred smoking the +F+H WT and achieved the largest plasma nicotine boost in that condition. DISCUSSION: Findings underscore the complexity of setting product standards related to flavourants and humectants in WT. Future research evaluating whether WT smokers with high dependence would quit or reduce their WT smoking in response to removal of flavourants or humectants from WT is necessary to appreciate the full public health effects of such policies.


Assuntos
Tabagismo , Tabaco para Cachimbos de Água , Adulto , Biomarcadores , Monóxido de Carbono/análise , Humanos , Higroscópicos , Exposição por Inalação/análise , Nicotina/análise , Tabaco para Cachimbos de Água/efeitos adversos
13.
Environ Sci Pollut Res Int ; 29(28): 41941-41952, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34355325

RESUMO

Membrane distillation (MD) has been increasingly explored for treatment of various hyper saline waters, including lithium chloride (LiCl) solutions used in liquid desiccant air-conditioning (LDAC) systems. In this study, the regeneration of liquid desiccant LiCl solution by a pilot direct contact membrane distillation (DCMD) process is assessed using computer simulation. Unlike previous experimental investigations, the simulation allows to incorporate both temperature and concentration polarisation effects in the analysis of heat and mass transfer through the membrane, thus enabling the systematic assessment of the pilot DCMD regeneration of the LiCl solution. The simulation results demonstrate distinctive profiles of water flux, thermal efficiency, and LiCl concentration along the membrane under cocurrent and counter-current flow modes, and the pilot DCMD process under counter-current flow is superior to that under cocurrent flow regarding the process thermal efficiency and LiCl concentration enrichment. Moreover, for the pilot DCMD regeneration of LiCl solution under the counter-current flow, the feed inlet temperature, LiCl concentration, and especially the membrane leaf length exert profound impacts on the process performance: the process water flux halves from 12 to 6 L/(m2·h) whilst thermal efficiency decreases by 20% from 0.46 to 0.37 when the membrane leaf length increases from 0.5 to 1.5 m.


Assuntos
Destilação , Purificação da Água , Simulação por Computador , Destilação/métodos , Higroscópicos , Cloreto de Lítio , Membranas Artificiais , Soluções , Purificação da Água/métodos
14.
Chem Phys Lipids ; 243: 105165, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34971600

RESUMO

Humectants are used widely in topical formulations as they provide cosmetic and health benefits to skin. Of particular interest to our laboratories is the interaction of humectants in phospholipid based topical skin care formulations. This study probed the effects of three exemplary humectants on a fully hydrated lecithin system (DPPC) by use of X-ray scattering and differential scanning calorimetry. While the three humectants affected the nanostructure of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC, bilayers in a similar manner, leading to an increased membrane order, differences in the effect on the thermal behaviour of DPPC suggest that betaine and sarcosine interacted via a different mechanism compared to acetic monoethanolamide, AMEA. At concentrations above 0.4 M, betaine and sarcosine stabilised the gel phase by depletion of the interfacial water via the preferential exclusion mechanism. At the same time, a slight increase in the rigidity of the membrane was observed with an increase in the membrane thickness. Overall, the addition of betaine or sarcosine resulted in an increase in the pre- and main transition temperatures of DPPC. AMEA, on the other hand, decreases both transition temperatures, and although the interlamellar water layer was also decreased, there was evidence from the altered lipid chain packing, that AMEA molecules are present also at the bilayer interface, at least at high concentrations. Above the melting point in the fluid lamellar phase, none of the humectants induced significant structural changes, neither concerning the bilayer stacking order nor its overall membrane fluidity. An humectant-induced increase in the Hamaker constant is the most plausible explanation for the observed reduction of the inter-bilayer distances, both in the gel and fluid phase.


Assuntos
Higroscópicos , Nanoestruturas , 1,2-Dipalmitoilfosfatidilcolina/química , Betaína , Varredura Diferencial de Calorimetria , Lecitinas , Bicamadas Lipídicas/química , Sarcosina , Água
15.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1058-1066, Sept.-Oct. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345256

RESUMO

Reducing the mortality rate is of a great economic importance for pig farming. Therefore, it is necessary to define the conditions in the farrowing unit based on the performance of the piglets, and specific hematological and biochemical parameters. Therefore, the aim of this paper is to examine the importance of using skin moisture absorbent and its influence in preventing hypothermia, which causes great economic losses in pig production. The experiment was set up on a commercial farm in Serbia and included 92 pigs divided into the experimental and control group. Body temperature values, body weight and blood parameters were monitored. The obtained values indicate that there is a significantly positive correlation of body temperature change and body weight values, and body temperature showed a significantly higher increase in the experimental group compared to the control group. The results obtained from hematological and biochemical parameters provide a clearer picture of the metabolic processes in piglets in the farrowing unit and can be used to further improve pig production and as a complement to genetic enhancement.(AU)


A redução da taxa de mortalidade é de grande importância econômica para a suinocultura. Portanto, é necessário definir as condições na unidade de parto com base no desempenho dos leitões, para serem parâmetros hematológicos e bioquímicos específicos. Portanto, o objetivo deste trabalho é examinar a importância do uso de absorvente de umidade na pele e sua influência na prevenção da hipotermia, que causa grandes perdas econômicas na produção de suínos. A experiência foi montada em uma fazenda comercial na Sérvia, e incluiu 92 porcos divididos no grupo experimental e de controle. Os valores de temperatura corporal, pesos corporais e parâmetros sanguíneos foram monitorados. Os valores obtidos indicam que existe uma correlação significativamente positiva entre os valores da temperatura corporal e dos pesos corporais, e a temperatura corporal mostrou um aumento significativamente maior no grupo experimental em comparação com o grupo de controle. Os resultados obtidos a partir de parâmetros hematológicos e bioquímicos fornecem uma imagem mais clara dos processos metabólicos em leitões na unidade de parto e podem ser usados para melhorar ainda mais a produção de suínos e como um complemento ao melhoramento genético.(AU)


Assuntos
Animais , Sus scrofa/sangue , Higroscópicos/uso terapêutico , Umidade/prevenção & controle , Hipotermia/diagnóstico , Hipotermia/prevenção & controle , Sérvia
16.
J Basic Microbiol ; 61(9): 808-813, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34309880

RESUMO

Granular microsclerotial formulations of entomopathogenic fungi deserve attention because of their post-application, in situ production of new conidia that enhance and prolong mycoinsecticidal efficacy against a target pest insect. Because high ambient moisture is a crucial condition to induce fungal development and conidiogenesis on granules, we tested the impacts of the additions of three humectants-glycerin, propylene glycol, and polyethylene glycol 400-on water absorption by pellets incorporating microsclerotia of Metarhizium humberi IP 46 with microcrystalline cellulose or vermiculite carriers, and on the production of infective conidia of IP 46 microsclerotia in ambient humidities suboptimal for routine conidiogenesis. Glycerin facilitated greater and faster absorption of water than the other humectants. Microcrystalline cellulose absorbed low quantities of water without any added humectant whereas vermiculite did not. IP 46 did not grow or sporulate on pellets prepared with or without glycerin at 86% relative humidity (RH) or on control pellets without glycerin at 91% RH; conidial production on pellets prepared with vermiculite or microcrystalline cellulose and 10% glycerin reached 1.1 × 105 conidia/mg and 1 × 105 conidia/mg, respectively, after 20 days of exposure at 91% RH. Hence, these results strongly support glycerin as a suitable humectant for granular microsclerotial formulations of this fungus.


Assuntos
Higroscópicos/farmacologia , Metarhizium/efeitos dos fármacos , Metarhizium/fisiologia , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento , Glicerol/farmacologia , Higroscópicos/classificação , Controle Biológico de Vetores , Propilenoglicol/farmacologia , Água/metabolismo
17.
Int J Cosmet Sci ; 43(5): 601-609, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34228831

RESUMO

OBJECTIVE: Humectants perform essential roles in the formulation of topical moisturizing products in terms of delivery of active ingredients, consumer experience and biophysical behaviour. How they retain and release water is key to understanding their behaviour. METHODS: Dynamic vapour sorption (DVS) was used to monitor the dehydration kinetics of three humectants widely used in topical formulations-glycerine, dexpanthenol and urea. Model aqueous solutions with concentrations of 20% w/w were tested and compared against pure deionized water. RESULTS: The three humectants varied in their ability to retain water during the dehydration process. Dexpanthenol was able to retain water most efficiently during the latter stages of dehydration. Urea demonstrated evidence of crystallization during the final stage of water loss, which was not shown by glycerine or dexpanthenol. CONCLUSIONS: Humectants perform vital roles in the formulation of consumer acceptable topical products including the delivery of actives to the skin. Their ability to influence water movement in the skin is also essential for the maintenance of stratum corneum flexibility. DVS assessment of aqueous solutions has demonstrated how the behaviour of three commonly used humectants differs. Knowledge of the mechanisms by which these humectants operate enables the formulator to develop topical products optimized for the roles for which they are intended.


OBJECTIF: Les agents humectants jouent un rôle essentiel dans la formulation des produits hydratants topiques en termes de délivrance des principes actifs, d'expérience client et de comportement biophysique. La façon dont ils retiennent et libèrent l'eau est essentielle pour comprendre leur comportement. MÉTHODES: La gravimétrie d'adsorption de vapeur d'eau (Dynamic Vapour Sorption, DVS) a été utilisée pour surveiller la cinétique de déshydratation de trois humectants largement utilisés dans les formulations topiques : glycérine, dexpanthénol et urée. Des solutions aqueuses modèles avec des concentrations de 20 % p/p ont été testées et comparées à de l'eau pure déionisée. RÉSULTATS: Les trois humectants ont varié dans leur capacité à retenir l'eau pendant le processus de déshydratation. Le dexpanthénol a été capable de retenir l'eau plus efficacement pendant les dernières étapes de la déshydratation. L'urée a démontré des signes de cristallisation pendant la perte d'eau au stade final qui n'a pas été démontrée par la glycérine ou le dexpanthénol CONCLUSIONS: Les agents humectants jouent un rôle essentiel dans la formulation des produits topiques acceptables pour les consommateurs, y compris l'administration de principes actifs sur la peau. Leur capacité à influencer le mouvement de l'eau dans la peau est également essentielle pour maintenir la flexibilité de la couche cornée. L'évaluation DVS des solutions aqueuses a démontré comment le comportement de trois humectants couramment utilisés diffère. La connaissance des mécanismes par lesquels fonctionnent ces humectants permet au formulateur de développer des produits topiques optimisés pour les rôles auxquels ils sont destinés.


Assuntos
Cosméticos/química , Glicerol/química , Higroscópicos/química , Ácido Pantotênico/análogos & derivados , Ureia/química , Água/química , Ácido Pantotênico/química
18.
Environ Sci Pollut Res Int ; 28(33): 45609-45618, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33871776

RESUMO

Producing clean water via renewable solar energy and available low-cost natural resources is one of paramount issues for the near future sustainable cleaner production theme to promote civilization. This work investigates the transient behavior of a solar-driven clean water extraction system from air by various desiccant natural and hybrid composite materials. Different single composite desiccant materials, hybrid single composite desiccant material, and hybrid multi-layers composite desiccant materials were examined using an efficient design of a solar glass box with four glass faces and square base setup. Nine different single composite desiccant materials were compared for water production from atmospheric air considering jute, wool, cotton, and maize starch host materials. The effect of CaCl2 solution concentration on the hybridization of such materials was also investigated to examine and optimize their water productivity efficiency. Thirteen hybrid multi-layer starch-based composite desiccant material types were utilized. Different layer combinations and weight percentages of hybrid composite desiccant materials were optimized based on the performance in the single hybrid composites stages including wool/CaCl2/starch, jute/CaCl2/starch, and cotton/CaCl2/starch. Results have indicated that the transient behavior of water productivity of composite desiccants increased as the wool percentage by mass in the composite has been increased. The transient behavior of water productivity of both single and hybrid multi-layer composites reached its maximum at 1:00 o'clock PM. The quality of extracted water was analyzed using total dissolved solids (TDS) test and found to be within the excellent category of clean water suitable for human being. Water generated from the samples that contain only natural fibers and starch was the cleaner and non-toxic.


Assuntos
Higroscópicos , Água , Vidro , Humanos , Amido , Têxteis
19.
Am J Physiol Lung Cell Mol Physiol ; 320(6): L1064-L1073, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33825493

RESUMO

In the United States, millions of adults use electronic cigarettes (e-cigs), and a majority of these users are former or current cigarette smokers. It is unclear, whether prior smoking status affects biological responses induced by e-cigs. In this study, differentiated human nasal epithelial cells (hNECs) from nonsmokers and smokers at air-liquid interface were acutely exposed to the e-cig generated aerosols of humectants, propylene glycol (PG), and glycerol (GLY). Mucin levels were examined in the apical washes, and cytokine levels were assessed in the basolateral supernatants 24 h postexposure. The aerosol from the GLY exposure increased mucin 5, subtype AC (MUC5AC) levels in the apical wash of hNECs from nonsmokers, but not smokers. However, the aerosol from GLY induced pro-inflammatory responses in hNECs from smokers. We also exposed hNECs from nonsmokers and smokers to e-cig generated aerosol from PG:GLY with freebase nicotine or nicotine salt. The PG:GLY with freebase nicotine exposure increased MUC5AC and mucin 5, subtype B (MUC5B) levels in hNECs from nonsmokers, but the nicotine salt exposure did not. The PG:GLY with nicotine salt exposure increased pro-inflammatory cytokines in hNECs from smokers, which was not seen with the freebase nicotine exposure. Taken together, these data indicate that the e-cig generated aerosols from the humectants, mostly GLY, and the type of nicotine used cause differential effects in airway epithelial cells from nonsmokers and smokers. As e-cig use is increasing, it is important to understand that the biological effects of e-cig use are likely dependent on prior cigarette smoke exposure.


Assuntos
Células Epiteliais/efeitos dos fármacos , Nicotina/farmacologia , não Fumantes , Fumantes , Vaping/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Glicerol/farmacologia , Humanos , Higroscópicos/farmacologia , Pulmão/efeitos dos fármacos , Propilenoglicol/farmacologia
20.
Int J Pharm Compd ; 25(2): 126-128, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798112

RESUMO

Humectants, hygroscopic substances used to minimize water loss and to prevent the drying out of different types of products, are in common use not only in pharmaceuticals but also in foods, cosmetics, etc. The proper selection of a humectant in a pharmaceutical formula depends upon the dosage form, ingredients, physical and chemical characteristics, as well as stability issues. This article discusses the importance of humectants and their applications in pharmaceutics.


Assuntos
Excipientes , Higroscópicos , Composição de Medicamentos , Água
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