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1.
J Sci Food Agric ; 104(3): 1723-1731, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37851602

RESUMO

BACKGROUND: In the present work, acute gastric ulcer models were constructed by administering hydrochloric acid/ethanol. The mice ingested white jade snail secretion (WJSS) through gastric infusion. Ulcer areas in gastric tissue were recorded, and malondialdehyde (MDA) and superoxide dismutase (SOD) were also measured. Notably, high-throughput 16S rDNA analysis of intestinal flora and determination of amino acid composition in feces were performed to understand the effect of WJSS on model mice. RESULTS: Compared with the control group, the ulcer area in the WJSS low-, medium- and high-concentration groups declined by 28.02%, 39.57% and 77.85%, respectively. MDA content decreased by 24.71%, 49.58% and 64.25%, and SOD relative enzyme activity fell by 28.19%, 43.37% and 9.60%, respectively. The amounts of amino acids in the low-, medium- and high-concentration groups were slightly lower, and probiotic bacteria such as Bacteroidetes and Lactobacillales increased in different-concentration WJSS groups. Adding WJSS contributes to the establishment of beneficial intestinal flora and the absorption of amino acids. CONCLUSION: Our results showed that WJSS has a beneficial effect on inhibiting hydrochloric acid-ethanolic gastric ulcers, suggesting that WJSS has excellent potential as a novel anti-ulcer agent. Combined with ulcer area, MDA content, SOD content, gut probiotics and other indicators, a high concentration of WJSS had the best protective effect on acute gastric ulcer. © 2023 Society of Chemical Industry.


Assuntos
Antiulcerosos , Úlcera Gástrica , Camundongos , Animais , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/metabolismo , Antioxidantes/metabolismo , Ácido Clorídrico , Úlcera/tratamento farmacológico , Úlcera/metabolismo , Antiulcerosos/metabolismo , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Etanol/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Extratos Vegetais/metabolismo , Aminoácidos/metabolismo , Mucosa Gástrica/metabolismo
2.
Environ Sci Pollut Res Int ; 30(54): 114886-114900, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37875755

RESUMO

The accurate calculation of the contribution which provided by clay minerals in coal on methane adsorption not only bares a significant importance for evaluating the effectiveness of acid stimulation in improving permeability and estimating the coalbed methane reserves but also serves a guide for the governance and utilization of methane resources. In this study, hydrochloric acid (HCl) and hydrofluoric acid (HF) were used to remove specific minerals in Qingdong coal samples. We firstly analyzed the mineral compositions of coal samples with different acidification treatments based on the X-ray diffraction (XRD) experiments, together with analysis of the changes in pore morphology and adsorption capacity. The results showed that acidification did not significantly change the shape of the pores, which remained slit-/plate-like pore. However, the altered adsorption capacity of the coal samples was attributed to changes in pore structure and mineral distribution. Acid erosion of mesopores promoted the transition from mesopores to macropores, contributing to an increase of 8.4% and 24.36% in the percentage of macropores in coal samples treated with HCl and HF, respectively. Fractal dimension D1 grew from 2.2193 to 2.3888 and 2.2572, respectively, but D2 decreased from 2.6146 to 2.5814 and 2.5433, indicating an increment in pore surface roughness and a simplification of the pore structure. The mineral richness of the coal seams should be taken into consideration when applying acid stimulation to increase permeability due to that the acidification products may block the passage of gas migration when the mineral content is slight, which can hinder gas extraction. The aim of this study is to quantitatively determine the contribution rate of clay minerals in coal to methane adsorption with a calculation method is provided by combining pore parameters and limit adsorption capacity, resulting in a contribution rate of 15%.


Assuntos
Carvão Mineral , Ácido Clorídrico , Adsorção , Argila , Ácido Fluorídrico , Metano , Minerais , Concentração de Íons de Hidrogênio
3.
PLoS One ; 18(7): e0288813, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37463180

RESUMO

Shiso (Perilla frutescens var crispa f. purprea) is a traditional medicinal herb that exerts anti-inflammatory effects and alleviates lower urinary tract symptoms. In this study, we examined the effects of rosmarinic acid, a major polyphenol in shiso, on urinary function and the bladder in a rat hydrochloric acid-induced cystitis model. Sprague-Dawley rats were administered intravesically with hydrochloric acid or saline solution (control) to induce cystitis. Afterwards, the rats were administered orally with distilled water or rosmarinic acid for three days and then the intravesical pressure was measured, a stretch stimulation test was performed using the harvested bladder, and histological and biochemical analyses were performed. In addition, we investigated the effects of rosmarinic acid on the expression of inflammation-related molecules in normal human bladder epithelial cells. Rosmarinic acid ameliorated hydrochloric acid-induced shortening of micturition interval by 49%. In hydrochloric acid-treated bladders, significantly more prostaglandin E2 was released after stretching; however, rosmarinic acid suppressed its release to control levels. Rosmarinic acid also reduced hydrochloric acid-induced epithelial thickening and the levels of inflammatory molecules in the bladder. Furthermore, rosmarinic acid suppressed interleukin 1ß-induced increases in Cox2 and Il6 expression in bladder epithelial cells. These findings indicate that rosmarinic acid can ameliorate hydrochloric acid-induced cystitis in rats and that these effects are due, at least in part, to its anti-inflammatory effects on the bladder and inhibition of stretch-induced prostaglandin E2 release.


Assuntos
Cistite , Ácido Clorídrico , Humanos , Ratos , Animais , Ratos Sprague-Dawley , Ácido Clorídrico/efeitos adversos , Dinoprostona/efeitos adversos , Cistite/induzido quimicamente , Cistite/tratamento farmacológico , Cistite/metabolismo , Anti-Inflamatórios/uso terapêutico , Ácido Rosmarínico
4.
Environ Sci Pollut Res Int ; 30(29): 73116-73136, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37213019

RESUMO

With the steady progress of ultra-low emissions in various industries, the management of unconventional pollutants is gradually attracting attention. A such unconventional pollutant that negatively affects many different processes and pieces of equipment is hydrogen chloride (HCl). Although it has strong advantages and potential in the treatment of industrial waste gas and synthesis gas, the process technology of removing HCl by calcium- and sodium-based alkaline powder has not yet been thoroughly studied. The impact of reaction factors on the dechlorination of calcium- and sodium-based sorbents is reviewed, including temperature, particle size, and water form. The most recent developments in sodium- and calcium-based sorbents for capturing hydrogen chloride were presented, and the dechlorination capabilities of various sorbents were contrasted. In the low-temperature range, sodium-based sorbents had a stronger dechlorination impact than calcium-based sorbents. Surface chemical reactions and product layer diffusion between solid sorbents and gases are crucial mechanisms. Meanwhile, the effect of the competitive behavior of SO2 and CO2 with HCl on the dechlorination performance has been taken into account. The mechanism and necessity of selective hydrogen chloride removal are also provided and discussed, and future research directions are pointed out to provide the theoretical basis and technical reference for future industrial practical applications.


Assuntos
Cálcio , Poluentes Ambientais , Ácido Clorídrico , Sódio , Temperatura , Gases , Adsorção
5.
Int J Biol Macromol ; 236: 123953, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36898465

RESUMO

The demand for obtaining pectin from new sources has been continuously increasing. The abundant but underutilized thinned-young apple is a potential source of pectin. In this study, an organic acid (i.e., citric acid) and two inorganic acids (i.e., hydrochloric acid and nitric acid) commonly used in commercial pectin production were applied to extract pectin from three varieties of thinned-young apples. The physicochemical and functional properties of the thinned-young apple pectin were comprehensively characterized. The highest pectin yield (8.88 %) was obtained from Fuji apple using citric acid extraction. All pectin was high methoxy pectin (HMP) and rich in RG-I regions (>56 %). The citric acid extracted pectin had the highest molecular weight (Mw) and lowest degree of esterification (DE) values, and exhibited great thermal stability and shear-thinning property. Furthermore, Fuji-apple pectin possessed significantly better emulsifying properties compared to pectin obtained from the other two varieties of apples. Thus, pectin extracted with citric acid from Fuji thinned-young apples has great potential to be applied in the food industry as a natural thickener and emulsifier.


Assuntos
Malus , Pectinas , Pectinas/química , Malus/química , Emulsificantes/química , Ácido Cítrico/química , Ácido Clorídrico
6.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5256-5263, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36472032

RESUMO

Because of the complex components, simple content determination can hardly reflect the overall quality of Guizhi Fuling Capsules. Therefore, it is necessary to carry out a multi-component dissolution test. The variability of quality among different batches of products from different manufacturers is a common problem of Chinese medicine solid preparations. To comprehensively control the quality of Guizhi Fuling Capsules, we studied the dissolution behaviors of 7 index components in the capsules under different conditions, and investigated the consistency of dissolution behaviors among different batches of products from the same manufacturer. The basket method of general rule 0931 in Chinese Pharmacopoeia was adopted, and the rotating speeds were set at 50, 75, and 100 r·min~(-1), respectively. The hydrochloric acid solution(pH 1.2), acetate buffer solution(pH 4.0), pure water, and phosphate buffer solution(pH 6.8) were used as the dissolution media. Automatic sampling was carried out at the time points of 5, 10, 20, 30, 45, and 60 min, respectively. The cumulative dissolution of 7 index components was measured through ultra-performance liquid chromatography(UPLC). The difference factor f_1 and similarity factor f_2 were calculated to comprehensively evaluate the similarity of the dissolution curves among 8 batches of Guizhi Fuling Capsules, and a variety of dissolution and release equations were fitted. The results showed that multiple components had faster dissolution rates at higher rotating speed and in hydrochloric acid medium. The 8 batches of Guizhi Fuling capsules showed the average f_1 value lower than 15 and the average f_2 value higher than 50, which indicated that different batches of products had similar dissolution behaviors. Most components had synchronous dissolution behaviors and similar release cha-racteristics. This study provides a reference for the quality consistency evaluation among batches, processing optimization, and dosage form improvement of Guizhi Fuling Capsules.


Assuntos
Medicamentos de Ervas Chinesas , Wolfiporia , Cápsulas , Solubilidade , Ácido Clorídrico , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão
7.
Artigo em Inglês | MEDLINE | ID: mdl-36293860

RESUMO

A novel diphasic sheeting device (DSD) including complemental feeding stage and complemental disintegrating stage for dislodging features of Cd(II), was investigated. The complemental feeding stage included feeding liquor and Bis(2,4,4 trimethylamyl) dithiophosphonic acid (Cyanex-301) as the carrier in petroleum, and the complemental disintegrating stage included Cyanex-301 as the carrier in petroleum and hydrochloric acid as the disintegrating reagent. The impacts of volumetric ratio of sheeting liquor and feeding liquor(S/F), initial molarity of Cd(II) and ion intensity of the feeding liquor, pH, volumetric ratio of sheeting liquor and disintegrating reagent (S/D), molarity of hydrochloric acid liquor, Cyanex-301 molarity in the complemental disintegrating stage on dislodging of Cd(II), the virtues of DSD compared to the traditional sheeting device, the constancy of system, the reuse of sheeting liquor, and the retention of the sheeting stage were also investigated. Experimental results illustrated that the optimum dislodging conditions of Cd(II) were achieved as hydrochloric acid molarity was 4.00 mol/L, Cyanex-301 molarity was 0.150 mol/L, and S/D was 1:1 in the complemental disintegrating stage, S/F was 1:10, and pH was 5.00 in the complemental feeding stage. The ion intensity of the complemental feeding stage had no distinct impact on the dislodging feature of Cd(II). When initial Cd(II) molarity was 3.20 × 10-4 mol/L, the Cd(II) dislodging percentage was up to 92.9% in 210 min. The dynamic formula was inferred on the basis of the theorem of mass transferring and the interfacial chemistry.


Assuntos
Compostos Organotiofosforados , Petróleo , Cádmio , Ácido Clorídrico , Indicadores e Reagentes
8.
J Med Life ; 15(8): 1038-1046, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36188655

RESUMO

Local plants can save natural resources and be used as a source of biologically active compounds, which can be high-quality, effective, and safe ingredients for pharmacological or chemical industries. Therefore, this study aimed to investigate the properties of two medicinal plants - the fine-scaled larch (Lárix Kaémpferi) and Siberian larch (Lárix Sibirica), which are growing in the Republic of Kazakhstan. We compared the two types of larches according to botanical affiliation and species description. We studied the alcoholic extracts from Lárix Kaémpferi and Lárix Sibirica to determine their physical and chemical properties. The data on the chemical composition of extractive compounds were generalized and systematized. The authenticity of Lárix Kaémpferi and Lárix Sibirica was established by external, anatomical, and diagnostic signs in microscopic examination and qualitative reactions. Specific indicators and their norms for raw materials were identified. This is the standard for both types of larch and determines their quality. We experimented with grinding fineness for studied materials and tested the impurities and moisture content of raw materials, total ash, and ash insoluble in a 10% hydrochloric acid solution. Determination of heavy metals and radionuclides was also considered. The quality specifications were developed based on the standardization of fine-scaled larch and Siberian larch.


Assuntos
Larix , Metais Pesados , Humanos , Ácido Clorídrico , Cazaquistão , Larix/química , Medicamentos sem Prescrição , Extratos Vegetais
9.
PLoS One ; 17(10): e0274084, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36227874

RESUMO

Fossils exposed at the surface are an integral component of the paleontologic record and provide an archive of past life. However, it is widely known that fossils are not stable indefinitely upon exposure to surface conditions such as physical, chemical, and biological processes, and this last phase of taphonomy is poorly understood. Studies regarding the longevity of fossils subject to weathering, such as acidic precipitation, are absent in the literature. The goal of this study was to experimentally determine vertebrate fossil dissolution rates under variable pH conditions in a controlled laboratory setting. It was hypothesized that fossils would dissolve within acidic solutions and do so at an increasing rate when exposed to increasingly acidic solutions. The experiments were conducted on three fossil vertebrae in triplicate in closed reaction vessels at pH 4, 5, and 6. The fossils were completely submerged for 21 days in a tap water solution with the pH adjusted using 0.1N hydrochloric acid (HCl). Fossil dissolution was quantified by changes to: (1) fossil mass; (2) elemental chemistry of water and fossils with inductively coupled plasma mass spectrometry (ICP-MS); (3) fossil mineralogy with X-ray diffraction (XRD); and (4) histologic structures with thin section analyses. All fossils exhibited mass loss, which increased with decreasing pH conditions, and was greatest under pH 4 (477 to 803 mg loss). The elemental analyses with ICP-MS indicated an increase of both calcium (maximum increase of 315 ppm) and phosphorus (increase of 18 ppm) in aqueous solutions with increasing pH and a loss of those same elements from the fossils (maximum loss of 10 ppm Ca and 6 ppm P). XRD revealed loss of gypsum in all post-dissolution samples. Taken together, the results of ICP-MS and XRD suggest dissolution of the primary mineral phases, including hydroxylapatite, and secondary phases, particularly calcite and gypsum, resulting in an estimated mass loss at pH 4 of 23 to 28 mg per day. Thin section analysis showed degradation of both cortical and trabecular bone in all post-dissolution images, demonstrating physical changes to the fossils as a result of water-rock interactions. These findings constitute the first quantitative analysis of fossil dissolution rates and provide insights into this last stage of taphonomy, addressing a largely understudied potential bias in the vertebrate fossil record.


Assuntos
Fósseis , Ácido Clorídrico , Cálcio , Carbonato de Cálcio/química , Sulfato de Cálcio , Durapatita , Concentração de Íons de Hidrogênio , Fósforo , Solubilidade , Água
10.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142236

RESUMO

Gastric cancer (GC) has high incidence rates and constitutes a common cause of cancer mortality. Despite advances in treatment, GC remains a challenge in cancer therapy which is why novel treatment strategies are needed. The interest in natural compounds has increased significantly in recent years because of their numerous biological activities, including anti-cancer action. The isolation of the bioactive compounds from Coptis chinensis Franch was carried out with the Centrifugal Partition Chromatography (CPC) technique, using a biphasic solvent system composed of chloroform (CHCl3)-methanol (MeOH)-water (H2O) (4:3:3, v/v) with an addition of hydrochloric acid and trietylamine. The identity of the isolated alkaloids was confirmed using a high resolution HPLC-MS chromatograph. The phytochemical constituents of Coptis chinensis such as berberine, jatrorrhizine, palmatine and coptisine significantly inhibited the viability and growth of gastric cancer cell lines ACC-201 and NCI-N87 in a dose-dependent manner, with coptisine showing the highest efficacy as revealed using MTT and BrdU assays, respectively. Flow cytometry analysis confirmed the coptisine-induced population of gastric cancer cells in sub-G1 phase and apoptosis. The combination of coptisine with cisplatin at the fixed-ratio of 1:1 exerted synergistic and additive interactions in ACC-201 and NCI-N87, respectively, as determined by means of isobolographic analysis. In in vivo assay, coptisine was safe for developing zebrafish at the dose equivalent to the highest dose active in vitro, but higher doses (greater than 10 times) caused morphological abnormalities in larvae. Our findings provide a theoretical foundation to further studies on more detailed mechanisms of the bioactive compounds from Coptis chinensis Franch anti-cancer action that inhibit GC cell survival in in vitro settings.


Assuntos
Alcaloides , Alcaloides de Berberina , Berberina , Coptis , Medicamentos de Ervas Chinesas , Neoplasias Gástricas , Alcaloides/análise , Alcaloides/farmacologia , Animais , Berberina/análogos & derivados , Berberina/farmacologia , Alcaloides de Berberina/farmacologia , Bromodesoxiuridina , Clorofórmio , Cisplatino , Coptis/química , Coptis chinensis , Medicamentos de Ervas Chinesas/química , Ácido Clorídrico , Isoquinolinas , Metanol , Solventes , Neoplasias Gástricas/tratamento farmacológico , Água , Peixe-Zebra
11.
Anal Sci ; 38(11): 1449-1454, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35989408

RESUMO

Electrochemical reduction of emodin under acidic media occurs at a less negative potential when compared with that under neutral media. When emodin is electrochemically detected at a less negative potential, a decrease in background noise and improvement in specificity benefit the development of high-performance liquid chromatography with electrochemical detection (HPLC-ECD) for its determination. HPLC-ECD was performed using an octadecyl silica column, acetonitrile-water (60:40, v/v) containing 5 mmol L-1 hydrochloric acid and 10 mmol L-1 lithium perchlorate, as a mobile phase, and an applied potential at - 0.4 V vs. Ag/AgCl. Under these optimal HPLC-ECD conditions, the detection limit (signal-to-noise ratio, S/N = 3) of emodin was 0.61 µg L-1. When this HPLC-ECD system was applied to the determination of emodin in Polygoni Multiflori Radix (PMR) samples, other peaks did not appear close to the emodin peak on a chromatogram. The emodin contents in PMR samples were determined with relative standard deviations (RSDs, n = 6) of less than 3.9%, and their recoveries ranged from 92 to 106%. We have shown that our HPLC-ECD system performed an accurate, precise, and specific determination of emodin in PMR samples.


Assuntos
Medicamentos de Ervas Chinesas , Emodina , Polygonum , Cromatografia Líquida de Alta Pressão/métodos , Polygonum/química , Ácido Clorídrico , Medicamentos de Ervas Chinesas/química , Água , Acetonitrilas , Dióxido de Silício
12.
Anal Methods ; 14(35): 3366-3374, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36039897

RESUMO

This work presents the development of a microplate spectrophotometric method for determination of indole-3-carbinol in dietary supplements. The colorimetric procedure is based on the reaction of indole-3-carbinol with the p-dimethylaminocinnamaldehyde (DMACA) reagent under acidic conditions. The absorbance of the colored product measured at 675 nm was used to determine the target analyte. To achieve optimal spectrophotometric performance, the DMACA reagent concentration, the hydrochloric acid concentration, and the reaction time were optimized. The developed technique performed well under the optimal conditions, with a linear calibration range of 30 to 300 mg L-1 and a high correlation coefficient (r2 = 0.9954). The limit of detection and limit of quantification were 7.8 mg L-1 and 26.2 mg L-1, respectively. This approach demonstrated good repeatability (intra- and inter-day precision) with a % RSD lower than 9.4%, good accuracy with acceptable relative recoveries in the range of 98 to 106%, and high sample throughput (24 detection per min). This simple, rapid, and multi-sample analysis approach for routine analysis of indole-3-carbinol has the potential to be used for the quality control of dietary supplements.


Assuntos
Suplementos Nutricionais , Ácido Clorídrico , Cinamatos , Indicadores e Reagentes , Indóis
13.
Molecules ; 27(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35744870

RESUMO

Satsuma mandarin peel pectin was extracted by high hydrostatic pressure-assisted citric acid (HHPCP) or hydrochloric acid (HHPHP), and the physiochemical, structural, rheological and emulsifying characteristics were compared to those from conventional citric acid (CCP) and hydrochloric acid (CHP). Results showed that HHP and citric acid could both increase the pectin yield, and HHPCP had the highest yield (18.99%). Structural characterization, including NMR and FTIR, demonstrated that HHPHP showed higher Mw than the other pectins. The viscosity of the pectin treated with HHP was higher than that obtained with the conventional method, with HHPHP exhibiting significantly higher viscosity. Interestingly, all the pectin emulsions showed small particle mean diameters (D4,3 being 0.2-1.3 µm) and extremely good emulsifying stability with centrifugation and 30-day storage assays, all being 100%. Satsuma mandarin peel could become a highly promising pectin source with good emulsifying properties, and HHP-assisted acid could be a more efficient method for pectin extraction.


Assuntos
Citrus , Pectinas , Ácido Cítrico/química , Citrus/química , Ácido Clorídrico , Pressão Hidrostática , Pectinas/química
14.
Environ Sci Pollut Res Int ; 29(37): 55990-56003, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35322369

RESUMO

Garlic peel (GP) was chemically modified by using thiourea under hydrothermal treatment, which could selectively adsorb gold ions from the 1/10 dilute aqua regia media directly without needing the dangerous evaporation operation. The synthetic chloroauric solution and practical leach liquor of the waste PCB (printed circuit board) powder in dilute aqua regia were employed to assess the adsorption performance on the thiol-GP and the commercial quaternary ammonia anion resin of D201, respectively. It was experimentally confirmed that the adsorption efficiency of gold onto the thiol-GP and D201 resin both reached 100%, and the maximum adsorption capacity of thiol-GP gel was evaluated as 42.59 mg Au/g that was much larger than that of D201 resin (3.33 mg Au/g). The thiol-GP gel adsorption efficiency of other coexisting base metal ions like Cu2+, Ni2+, Al3+, and Fe3+ from dilute aqua regia leach liquor of the waste PCB powder was near zero, and only gold could be enriched by selective adsorption onto the thiol-GP gel. At least 3 cycles of adsorption/elution could be obtained without decreasing the adsorption efficiency drastically. The adsorbed gold on the thiol-GP was able to be eluted effectively by using the mixture solution of 0.1 M thiourea and 0.1 M hydrochloric acid, and finally the solid gold could be recovered by sodium borohydride through a reduction process. This study demonstrated a green, environmentally friendly, low-cost, and efficient method for selective recovery of gold from the dilute leach liquor (aqua regia) of waste circuit boards.


Assuntos
Resíduo Eletrônico , Alho , Ouro , Ácido Clorídrico , Íons , Ácido Nítrico , Pós , Compostos de Sulfidrila , Tioureia
15.
Microbiol Spectr ; 9(3): e0137721, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34908469

RESUMO

The dormancy continuum hypothesis states that in response to stress, cells enter different stages of dormancy ranging from unstressed living cells to cell death, in order to ensure their long-term survival under adverse conditions. Exposure of Listeria monocytogenes cells to sublethal stressors related to food processing may induce sublethal injury and the viable-but-nonculturable (VBNC) state. In this study, exposure to acetic acid (AA), hydrochloric acid (HCl), and two disinfectants, peracetic acid (PAA) and sodium hypochlorite (SH), at 20°C and 4°C was used to evaluate the potential induction of L. monocytogenes strain Scott A into different stages of dormancy. To differentiate the noninjured subpopulation from the total population, tryptic soy agar with 0.6% yeast extract (TSAYE), supplemented or not with 5% NaCl, was used. Sublethally injured and VBNC cells were detected by comparing plate counts obtained with fluorescence microscopy and by using combinations of carboxyfluorescein and propidium iodide (viable/dead cells). Induction of sublethal injury was more intense after PAA treatment. Two subpopulations were detected, with phenotypes of untreated cells and small colony variants (SCVs). SCVs appeared as smaller colonies of various sizes and were first observed after 5 min of exposure to 5 ppm PAA at 20°C. Increasing the stress intensity from 5 to 40 ppm PAA led to earlier detection of SCVs. L. monocytogenes remained culturable after exposure to 20 and 30 ppm PAA for 3 h. At 40 ppm, after 3 h of exposure, the whole population was considered nonculturable, while cells remained metabolically active. These results corroborate the induction of the VBNC state. IMPORTANCE Sublethally injured and VBNC cells may evade detection, resulting in underestimation of a food product's microbial load. Under favorable conditions, cells may regain their growth capacity and acquire new resistant characteristics, posing a major threat for public health. Induction of the VBNC state is crucial for foodborne pathogens, such as L. monocytogenes, the detection of which relies almost exclusively on the use of culture recovery techniques. In the present study, we confirmed that sublethal injury is an initial stage of dormancy in L. monocytogenes that is followed by the VBNC state. Our results showed that PAA induced SCVs (a phenomenon potentially triggered by external factors) and the VBNC state in L. monocytogenes, indicating that tests of lethality based only on culturability may provide false-positive results regarding the effectiveness of an inactivation treatment.


Assuntos
Ácido Acético/farmacologia , Desinfetantes/farmacologia , Ácido Clorídrico/farmacologia , Listeria monocytogenes/crescimento & desenvolvimento , Ácido Peracético/farmacologia , Hipoclorito de Sódio/farmacologia , Contaminação de Alimentos/análise , Manipulação de Alimentos , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/isolamento & purificação , Listeriose/prevenção & controle
16.
Molecules ; 26(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34946501

RESUMO

Croton lechleri, commonly known as Dragon's blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy techniques. Chloroform alkaloid-rich extracts resulted in IE% of 57% at 50 ppm, attributed to the formation of a layer of organic compounds on the AB surface that hindered the dezincification process. The formulation of corrosion inhibitors from C. lechleri latex allows for the valorization of non-edible natural sources and the diversification of the offer of green corrosion inhibitors for the chemical treatment of heat exchangers.


Assuntos
Cobre/química , Croton/química , Ácido Clorídrico/química , Extratos Vegetais/química , Zinco/química , Corrosão
17.
Inhal Toxicol ; 33(9-14): 308-324, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34772293

RESUMO

OBJECTIVE: Solid composite propellants combustion, in aerospace and defense fields, can lead to complex aerosols emission containing high concentrations of alumina nanoparticles (Al2O3 NPs) and hydrogen chloride gas (HClg). Exposure to these mixtures by inhalation is thus possible but literature data toward their pulmonary toxicity are missing. To specify hazards resulting from these combustion aerosols, a pilot study was implemented. MATERIALS AND METHODS: Male Wistar rats were nose-only exposed to Al2O3 NPs (primary size 13 nm, 10 g/L suspension leading to 20.0-22.1 mg/m3 aerosol) and/or to HClg aerosols (5 ppm target concentration) following two exposure scenarios (single exposures (SE) or repeated exposures (RE)). Bronchoalveolar lavage fluids (BALF) content and lungs histopathology were analyzed 24 h after exposures. RESULTS: Repeated co-exposures increased total proteins and LDH concentrations in BALF indicating alveolar-capillary barrier permeabilization and cytolysis. Early pulmonary inflammation was induced after RE to Al2O3 NPs ± HClg resulting in PMN, TNF-α, IL-1ß, and GRO/KC increases in BALF. Both exposure scenarios resulted in pulmonary histopathological lesions (vascular congestions, bronchial pre-exfoliations, vascular and interalveolar septum edemas). Lung oxidative damages were observed in situ following SE. CONCLUSION: Observed biological effects are dependent on both aerosol content and exposure scenario. Results showed an important pro-inflammatory effect of Al2O3 NPs/HClg mixtures on the lungs of rat 24 h after exposure. This pilot study raises concerns toward potential long-term pulmonary toxicity of combustion aerosols and highlights the importance for further studies to be led in order to define dose limitations and exposure thresholds for risk management at the work place.


Assuntos
Nanopartículas , Pneumonia , Aerossóis/toxicidade , Óxido de Alumínio/toxicidade , Animais , Líquido da Lavagem Broncoalveolar , Ácido Clorídrico , Exposição por Inalação/efeitos adversos , Pulmão , Masculino , Nanopartículas/toxicidade , Projetos Piloto , Ratos , Ratos Wistar
18.
J Vet Sci ; 22(6): e78, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34697924

RESUMO

BACKGROUND: Recurrent subclinical mastitis (RScM) due to resistant bacteria has low clinical and bacteriological cure rates, often requiring the culling of cows. The sequential intra-mammary administration of enrofloxacin hydrochloride-dihydrate (enro-C) followed by ceftiofur HCl may be useful for treating these cases. OBJECTIVES: This study assessed the bacteriological and clinical cure-efficacies of the sequentially intramammary administration of enro-C, followed by ceftiofur HCl to treat RScM in Holstein/Friesian cows. METHODS: This trial was conducted in a herd with a high prevalence of RScM, and 20 Holstein/Friesian cows were included: 45% suffering subclinical mastitis and 38.9% of the mammary quarters affected. Twenty-nine bacterial isolates in vitro resistant to enro-C were obtained (coagulase-negative Staphylococcus spp, 55.2%; Staphylococcus aureus, 27.6%; Escherichia coli, 6.9%; Streptococcus uberis, 6.9%; Corynebacterium bovis, 3.4%). Polymerase chain reaction-isolated the following genes linked to enro-C resistance: chromosomal (gyrA) and plasmid (aac(6')-lb-cr). The treatments were as follows: twice-daily intramammary infusions of enro-C (300 mg/10 mL) for 5 days. Cows clinically considered treatment failures were also treated with intramammary ceftiofur (125 mg/10 mL, twice daily for 5 days. The clinical and bacteriological cure rates were carried out when completing each treatment phase and at 14 and 21 days, aided by a California mastitis test, somatic cell count, and failure to identify the initially causative bacteria. RESULTS: Enro-C achieved 65% clinical and bacteriological cure rates, and 100% cure rates were obtained after the rescue treatment with ceftiofur HCl. CONCLUSIONS: Outstanding clinical and bacteriological cure rates in cows affected by RScM were achieved with the consecutive intramammary infusions of enro-C, followed by ceftiofur HCl.


Assuntos
Infecções Bacterianas/veterinária , Cefalosporinas/uso terapêutico , Enrofloxacina/uso terapêutico , Mastite Bovina/tratamento farmacológico , Animais , Infecções Bacterianas/tratamento farmacológico , Bovinos , Cefalosporinas/administração & dosagem , Farmacorresistência Bacteriana , Enrofloxacina/administração & dosagem , Feminino , Ácido Clorídrico , Mastite Bovina/microbiologia , Recidiva
19.
Nutrients ; 13(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684599

RESUMO

We previously reported that female mice exhibit protection against chemically induced pulmonary fibrosis and suggested a potential role of estrogen. Phytoestrogens act, at least in part, via stimulation of estrogen receptors; furthermore, compared to residents of Western countries, residents of East Asian countries consume higher amounts of phytoestrogens and exhibit lower rates of pulmonary fibrosis. Therefore, we tested the hypothesis that dietary phytoestrogens ameliorate the severity of experimentally induced pulmonary fibrosis. Male mice placed on either regular soybean diet or phytoestrogen-free diet were instilled with 0.1 N HCl to provoke pulmonary fibrosis. Thirty days later, lung mechanics were measured as indices of lung function and bronchoalveolar lavage fluid (BALF) and lung tissue were analyzed for biomarkers of fibrosis. Mice on phytoestrogen-free diet demonstrated increased mortality and stronger signs of chronic lung injury and pulmonary fibrosis, as reflected in the expression of collagen, extracellular matrix deposition, histology, and lung mechanics, compared to mice on regular diet. We conclude that dietary phytoestrogens play an important role in the pathogenesis of pulmonary fibrosis and suggest that phytoestrogens (e.g., genistein) may be useful as part of a therapeutic regimen against hydrochloric acid-induced lung fibrosis and chronic lung dysfunction.


Assuntos
Dieta , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Fitoestrógenos/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Animais , Doença Crônica , Proteínas da Matriz Extracelular/metabolismo , Ácido Clorídrico , Inflamação/patologia , Contagem de Leucócitos , Pulmão/fisiopatologia , Lesão Pulmonar/complicações , Lesão Pulmonar/mortalidade , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Fitoestrógenos/farmacologia , Fibrose Pulmonar/complicações , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
20.
Molecules ; 26(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641616

RESUMO

Several Cissus species have been used and reported to possess medicinal benefits. However, the anti-inflammatory mechanisms of Cissus subtetragona have not been described. In this study, we examined the potential anti-inflammatory effects of C. subtetragona ethanol extract (Cs-EE) in vitro and in vivo, and investigated its molecular mechanism as well as its flavonoid content. Lipopolysaccharide (LPS)-induced macrophage-like RAW264.7 cells and primary macrophages as well as LPS-induced acute lung injury (ALI) and HCl/EtOH-induced acute gastritis mouse models were utilized. Luciferase assays, immunoblotting analyses, overexpression strategies, and cellular thermal shift assay (CETSA) were performed to identify the molecular mechanisms and targets of Cs-EE. Cs-EE concentration-dependently reduced the secretion of NO and PGE2, inhibited the expression of inflammation-related cytokines in LPS-induced RAW264.7 cells, and decreased NF-κB- and AP-1-luciferase activity. Subsequently, we determined that Cs-EE decreased the phosphorylation events of NF-κB and AP-1 pathways. Cs-EE treatment also significantly ameliorated the inflammatory symptoms of HCl/EtOH-induced acute gastritis and LPS-induced ALI mouse models. Overexpression of HA-Src and HA-TAK1 along with CETSA experiments validated that inhibited inflammatory responses are the outcome of attenuation of Src and TAK1 activation. Taken together, these findings suggest that Cs-EE could be utilized as an anti-inflammatory remedy especially targeting against gastritis and acute lung injury by attenuating the activities of Src and TAK1.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/administração & dosagem , Cissus/química , Etanol/efeitos adversos , Gastrite/tratamento farmacológico , Ácido Clorídrico/efeitos adversos , Lipopolissacarídeos/efeitos adversos , Macrófagos/citologia , Polifenóis/administração & dosagem , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Administração Oral , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Citocinas/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Gastrite/induzido quimicamente , Gastrite/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Extratos Vegetais/química , Polifenóis/química , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento , Quinases da Família src/genética
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