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1.
Chem Senses ; 45(7): 513-521, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32609815

RESUMO

Probing the neural mechanisms that underlie each sensory system requires the presentation of perceptually appropriate stimulus concentrations. This is particularly relevant in the olfactory system as additional odorant receptors typically respond with increasing stimulus concentrations. Thus, perceptual measures of olfactory sensitivity provide an important guide for functional experiments. This study focuses on aliphatic alcohols because they are commonly used to survey neural activity in a variety of olfactory regions, probe the behavioral limits of odor discrimination, and assess odor-structure activity relationships in mice. However, despite their frequent use, a systematic study of the relative sensitivity of these odorants in mice is not available. Thus, we assayed the ability of C57BL/6J mice to detect a homologous series of primary aliphatic alcohols (1-propanol to 1-heptanol) using a head-fixed Go/No-Go operant conditioning assay combined with highly reproducible stimulus delivery. To aid in the accessibility of our data, we report the animal's threshold to each odorant according to the 1) ideal gas condition, 2) nonideal gas condition (factoring in the activity of the odorant in the solvent), and 3) the liquid dilution of the odorant in the olfactometer. Of the odorants tested, mice were most sensitive to 1-hexanol and least sensitive to 1-butanol. These updated measures of murine sensitivity will hopefully guide experimenters in choosing appropriate stimulus concentrations for experiments using these odorants.


Assuntos
Álcoois Graxos/química , Limiar Sensorial/fisiologia , Olfato/fisiologia , 1-Butanol/química , 1-Butanol/farmacologia , 1-Propanol/química , 1-Propanol/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Álcoois Graxos/farmacologia , Feminino , Gases/química , Heptanol/química , Heptanol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Limiar Sensorial/efeitos dos fármacos
2.
J Infect Dis ; 219(7): 1044-1048, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30358855

RESUMO

Hepatitis B virus (HBV) infection is considered a major public health problem worldwide, and a significant number of reports on nosocomial and occupational outbreaks have been reported. This systematic investigation of HBV stability and susceptibility to different antiseptics revealed that HBV infectivity was very stable, with a half-life of >22 days at 37°C. At 4°C, infectivity was barely reduced for up to 9 months. Different alcohols and commercially available hand antiseptics had a virucidal effect against HBV. We propose that very strict compliance with established hygienic guidelines should be mandatory to avoid and prevent HBV infections.


Assuntos
Anti-Infecciosos Locais/farmacologia , Infecção Hospitalar/prevenção & controle , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/prevenção & controle , Doenças Profissionais/prevenção & controle , 1-Propanol/farmacologia , 2-Propanol/farmacologia , Linhagem Celular , Infecção Hospitalar/virologia , Meio Ambiente , Etanol/farmacologia , Higiene das Mãos/normas , Higienizadores de Mão/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Doenças Profissionais/virologia , Soro , Temperatura , Fatores de Tempo
3.
World J Microbiol Biotechnol ; 35(11): 164, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31637528

RESUMO

Odd-chain fatty acids (OCFAs) have been reported to possess pharmacological activity and have been used in the manufacture of agricultural and industrial chemicals. We here provided a new method to increase the OCFAs content in oil produced by Rhodococcus opacus PD630 through addition of 1-propanol to the fermentation media. The OCFAs in oil of R. opacus PD630 are primarily pentadecanoic acid (C15:0), heptadecanoic acid (C17:0) and heptadecenoic acid (C17:1). After adding 0.5-1.5% (v/v) 1-propanol, the production of oil increased from 1.27 g/L to 1.31-1.61 g/L, and the OCFAs content in oil increased by 46.7-55.1%. Metabolic intermediates determination and transcriptome analysis revealed that R. opacus assimilated 1-propanol through methylmalonyl-CoA pathway. When the nitrogen source was limited, propionyl-CoA was converted to propionyl-acyl carrier protein (ACP) which could be used as primer during the elongation of fatty acid synthesis. Then OCFAs were produced when odd number of propionyl-ACP was incorporated in the cycles of fatty acid synthesis.


Assuntos
1-Propanol/farmacologia , Ácidos Graxos/biossíntese , Rhodococcus/efeitos dos fármacos , Rhodococcus/metabolismo , 1-Propanol/metabolismo , Acil Coenzima A , Álcoois/farmacologia , Biomassa , Ácidos Graxos/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Fermentação , Redes e Vias Metabólicas , Rhodococcus/crescimento & desenvolvimento , Transcriptoma
4.
Bioprocess Biosyst Eng ; 39(2): 255-65, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26615414

RESUMO

The aim of the present study was to optimize the feeding proportion of glucose and propanol for erythromycin biosynthesis by real-time monitoring and exploring its limited ratio by the on-line multi-frequency permittivity measurement. It was found that the capacitance values were sensitive to the variation of biomass concentration and microbial morphology as well as the true state of cell growth. It was most favorable to both cell growth and secondary metabolism to keep the ratio of glucose to propanol at 4.3 (g/g). The specific growth rate calculated by the capacitance measurement correctly and accurately reflected the cell physiological state. An appropriate feed rate of propanol was crucial for cell growth and secondary metabolism, as well as to improve the quality of erythromycin-A. In addition, the erythromycin production titer (10,950 U/mL) was further enhanced by 4 % when the propanol feed was regulated by step-down strategy based on both OUR (oxygen uptake rate) and the on-line monitoring capacitance.


Assuntos
1-Propanol/metabolismo , Eritromicina/biossíntese , Consumo de Oxigênio/fisiologia , Saccharopolyspora/crescimento & desenvolvimento , 1-Propanol/farmacologia , Consumo de Oxigênio/efeitos dos fármacos
5.
Biochim Biophys Acta ; 1834(3): 708-16, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23270996

RESUMO

Polyproline II (PPII) fold, an unusual structural element was detected in the serine protease from Nocardiopsis sp. NCIM 5124 (NprotI) based on far UV circular dichroism spectrum, structural transitions of the enzyme in presence of GdnHCl and a distinct isodichroic point in chemical and thermal denaturation. The functional activity and conformational transitions of the enzyme were studied under various denaturing conditions. Enzymatic activity of NprotI was stable in the vicinity of GdnHCl upto 6.0M concentration, organic solvents viz. methanol, ethanol, propanol (all 90% v/v), acetonitrile (75% v/v) and proteases such as trypsin, chymotrypsin and proteinase K (NprotI:protease 10:1). NprotI seems to be a kinetically stable protease with a high energy barrier between folded and unfolded states. Also, an enhancement in the activity of the enzyme was observed in 1M GdnHCl upto 8h, in organic solvents (75% v/v) for 72h and in presence of proteolytic enzymes. The polyproline fold remained unaltered or became more prominent under the above mentioned conditions. However, it diminished gradually during thermal denaturation above 60°C. Thermal transition studies by differential scanning calorimetry (DSC) showed scan rate dependence as well as irreversibility of denaturation, the properties characteristic of kinetically stable proteins. This is the first report of PPII helix being the global conformation of a non structural protein, an alkaline serine protease, from a microbial source, imparting kinetic stability to the protein.


Assuntos
Proteínas de Bactérias/química , Endopeptidases/química , Peptídeos/química , Dobramento de Proteína , 1-Propanol/química , 1-Propanol/farmacologia , Acetonitrilas/química , Acetonitrilas/farmacologia , Actinomycetales/enzimologia , Proteínas de Bactérias/metabolismo , Biocatálise/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Dicroísmo Circular , Endopeptidases/metabolismo , Estabilidade Enzimática , Etanol/química , Etanol/farmacologia , Guanidina/química , Guanidina/farmacologia , Cinética , Metanol/química , Metanol/farmacologia , Peptídeos/metabolismo , Ligação Proteica , Desdobramento de Proteína , Temperatura , Tripsina/química , Tripsina/metabolismo
6.
J Mol Biol ; 435(11): 167953, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330283

RESUMO

Membranes form the first line of defence of bacteria against potentially harmful molecules in the surrounding environment. Understanding the protective properties of these membranes represents an important step towards development of targeted anti-bacterial agents such as sanitizers. Use of propanol, isopropanol and chlorhexidine can significantly decrease the threat imposed by bacteria in the face of growing anti-bacterial resistance via mechanisms that include membrane disruption. Here we have employed molecular dynamics simulations and nuclear magnetic resonance to explore the impact of chlorhexidine and alcohol on the S. aureus cell membrane, as well as the E. coli inner and outer membranes. We identify how sanitizer components partition into these bacterial membranes, and show that chlorhexidine is instrumental in this process.


Assuntos
1-Propanol , 2-Propanol , Antibacterianos , Clorexidina , Escherichia coli , Higienizadores de Mão , Staphylococcus aureus , Antibacterianos/farmacologia , Clorexidina/farmacologia , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Staphylococcus aureus/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , 1-Propanol/farmacologia , 2-Propanol/farmacologia , Higienizadores de Mão/farmacologia
7.
Biochim Biophys Acta ; 1812(5): 613-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21296661

RESUMO

Methionine metabolism is disrupted in patients with alcoholic liver disease, resulting in altered hepatic concentrations of S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and other metabolites. The present study tested the hypothesis that reductive stress mediates the effects of ethanol on liver methionine metabolism. Isolated rat livers were perfused with ethanol or propanol to induce a reductive stress by increasing the NADH/NAD(+) ratio, and the concentrations of SAM and SAH in the liver tissue were determined by high-performance liquid chromatography. The increase in the NADH/NAD(+) ratio induced by ethanol or propanol was associated with a marked decrease in SAM and an increase in SAH liver content. 4-Methylpyrazole, an inhibitor the NAD(+)-dependent enzyme alcohol dehydrogenase, blocked the increase in the NADH/NAD(+) ratio and prevented the alterations in SAM and SAH. Similarly, co-infusion of pyruvate, which is metabolized by the NADH-dependent enzyme lactate dehydrogenase, restored the NADH/NAD(+) ratio and normalized SAM and SAH levels. The data establish an initial link between the effects of ethanol on the NADH/NAD(+) redox couple and the effects of ethanol on methionine metabolism in the liver.


Assuntos
Etanol/farmacologia , Fígado/efeitos dos fármacos , NAD/metabolismo , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo , 1-Propanol/farmacologia , Animais , Anti-Infecciosos Locais/farmacologia , Fígado/metabolismo , Masculino , Oxirredução , Perfusão , Ratos , Ratos Sprague-Dawley
8.
Bioorg Med Chem Lett ; 22(8): 2807-10, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22450133

RESUMO

Optimization of a series of aminomethyl ketone diamine H(3)R antagonists to reduce the brain exposure by lowering the pKa, led to molecules with improved pharmacokinetic properties. Compounds 9, 19, and 25 had high affinity for human H(3)R and demonstrated in vivo H(3)R functional activity in the rat dipsogenia model. Compound 9 displayed modest wake-promoting activity in the rat EEG/EMG model.


Assuntos
Agonismo Inverso de Drogas , Agonistas dos Receptores Histamínicos , Cetonas/química , Vigília/efeitos dos fármacos , 1-Propanol/química , 1-Propanol/farmacologia , Animais , Agonistas dos Receptores Histamínicos/química , Agonistas dos Receptores Histamínicos/farmacologia , Humanos , Cetonas/farmacologia , Metilaminas/química , Metilaminas/farmacologia , Fenóis/química , Fenóis/farmacologia , Pirrolidinas/química , Pirrolidinas/farmacologia , Ratos , Transtornos do Sono do Ritmo Circadiano/tratamento farmacológico
9.
Int Orthop ; 36(4): 887-93, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22159657

RESUMO

PURPOSE: The reason for enhanced fracture healing in traumatic brain injury patients is not clearly understood. It is possible that factors inherent in the brain passing through the blood-brain barrier to the peripheral circulation, or a disruption of central nervous system (CNS) control of the sympathetic nervous system (SNS), stimulates the process of fracture healing. METHODS: In this study, we assessed proliferation [using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay] and differentiation [using alkaline phosphatase (ALP)] in rat osteoblasts incubated with gray matter or other tissue extracts with and without the addition of an α- or ß-adrenergic receptor blocker (phentolamine or propranolol). RESULTS: Gray matter extract from normal brain caused a dose-dependent increase in osteoblast proliferation and differentiation. Serum from normal rats enhanced differentiation but not proliferation. Alpha-receptor blockade had no effect on proliferation or differentiation. Beta-receptor blockade caused a partial, but statistically significant, decrease in gray matter stimulation of osteoblast differentiation. CONCLUSION: The results of this study indicate that gray matter extract from normal brain increases osteoblast proliferation and differentiation and that ß receptors may be involved in differentiation under these conditions.


Assuntos
Encéfalo/metabolismo , Osteoblastos/efeitos dos fármacos , Extratos de Tecidos/farmacologia , 1-Propanol/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Animais Recém-Nascidos , Química Encefálica , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Formazans/metabolismo , Osteoblastos/metabolismo , Fentolamina/farmacologia , Ratos , Ratos Sprague-Dawley , Sais de Tetrazólio/metabolismo
10.
J Infect Dis ; 204(12): 1830-8, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22013220

RESUMO

BACKGROUND: Hepatitis C virus (HCV) cross-contamination from inanimate surfaces or objects has been implicated in transmission of HCV in health-care settings and among injection drug users. We established HCV-based carrier and drug transmission assays that simulate practical conditions to study inactivation and survival of HCV on inanimate surfaces. METHODS: Studies were performed with authentic cell culture derived viruses. HCV was dried on steel discs and biocides were tested for their virucidal efficacy against HCV. Infectivity was determined by a limiting dilution assay. HCV stability was analyzed in a carrier assay for several days or in a drug transmission assay using a spoon as cooker. RESULTS: HCV can be dried and recovered efficiently in the carrier assay. The most effective alcohol to inactivate the virus was 1-propanol, and commercially available disinfectants reduced infectivity of HCV to undetectable levels. Viral infectivity on inanimate surfaces was detectable in the presence of serum for up to 5 days, and temperatures of about 65-70°C were required to eliminate infectivity in the drug transmission assay. CONCLUSIONS: These findings are important for assessment of HCV transmission risks and should facilitate the definition of stringent public health interventions to prevent HCV infections.


Assuntos
Desinfetantes/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C/transmissão , Viabilidade Microbiana/efeitos dos fármacos , Inativação de Vírus/efeitos dos fármacos , 1-Propanol/farmacologia , 2-Propanol/farmacologia , Contaminação de Equipamentos , Etanol/farmacologia , Glutaral/farmacologia , Hepacivirus/fisiologia , Hepatite C/prevenção & controle , Hepatite C/virologia , Humanos , Peróxidos/farmacologia , Compostos de Amônio Quaternário/farmacologia , Abuso de Substâncias por Via Intravenosa/virologia , Temperatura , Fatores de Tempo
11.
Microbiol Res ; 263: 127150, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35940109

RESUMO

Minimizing Aspergillus flavus growth is an effective strategy to mitigate aflatoxin contamination in food and agricultural products. In the present investigation, we attempted to utilize soil-associated yeasts from the Western and Eastern Ghats of India against A. flavus to reduce aflatoxin contamination. Forty-five yeast isolates were screened against A. flavus using overlay and dual plate assays. Among them, 12 isolates effectively inhibited the growth of A. flavus. The 18S rDNA gene sequence analysis identified the twelve antagonistic isolates as belonging to Saccharomyces cerevisiae, Suhomyces xylopsoci, Pichia kudriavzevii, and Candida tropicalis. From the isolated yeasts, S. cerevisiae strains were selected for further evaluation based on the potential antagonistic activity. Volatiles of S. cerevisiae effectively suppressed the mycelial growth of A. flavus (P < 0.05) up to 92.1 % at 7 DAI. Scanning electron microscopic images of the fungus exposed to volatiles showed hyphal deformity and mycelial damage. Aflatoxin B1 (AFB1) production was drastically reduced up to 99.0 % in the volatile-exposed fungus compared to the control. The yeast strain YKK1 showed consistent Aspergillus flavus growth inhibition (80.7 %) and AFB1 production (98.1 %) for 14 days. Gas chromatography-mass spectrophotometry analysis of the yeast volatiles revealed the presence of antimicrobial compounds, including 1-pentanol, 1-propanol, ethyl hexanol, ethanol, 2-methyl-1-butanol, ethyl acetate, dimethyl trisulfide, p-xylene, styrene, and 1,4-pentadiene. The evaluated compounds of yeast volatiles, including ethyl acetate, hexanal, 1-propanol, 1-heptanol, 1-butanol, and benzothiazole, inhibited the fungal growth and AFB1 production of Aspergillus flavus when applied as pure chemicals. Benzothiazole at 5 mM was responsible for a high level of growth inhibition (23.6 %) and reduction of AFB1 synthesis (93.5 %). Hence, volatile compounds produced by soil yeast strains could be a potential biocontrol mechanism against aflatoxin contamination.


Assuntos
Aflatoxinas , Aspergillus flavus , 1-Butanol/farmacologia , 1-Propanol/farmacologia , Aflatoxina B1/genética , Aflatoxina B1/farmacologia , Aflatoxinas/farmacologia , Benzotiazóis/farmacologia , Saccharomyces cerevisiae , Solo
12.
Antimicrob Resist Infect Control ; 11(1): 139, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369050

RESUMO

BACKGROUND: Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl sulphate (PBM) on resistance development, antibiotics cross-resistance, and virulence in Staphylococcus aureus. METHODS: The minimum inhibitory concentration (MIC) of PVP-I and PBM were determined against S. aureus ATCC 25923 using the agar-dilution method. Staphylococcus aureus ATCC 25923 was subjected to subinhibitory concentrations of the tested biocides in ten consecutive passages followed by five passages in a biocide-free medium; MIC was determined after each passage and after the fifth passage in the biocide-free medium. The developed resistant mutant was tested for cross-resistance to different antibiotics using Kirby-Bauer disk diffusion method. Antibiotic susceptibility profiles as well as biocides' MIC were determined for 97 clinical S. aureus isolates. Isolates were categorized into susceptible and resistant to the tested biocides based on MIC distribution pattern. The virulence of the biocide-resistant mutant and the effect of subinhibitory concentrations of biocides on virulence (biofilm formation, hemolysin activity, and expression of virulence-related genes) were tested. RESULTS: PVP-I and PBM MIC were 5000 µg/mL and 664 µg/mL. No resistance developed to PVP-I but a 128-fold increase in PBM MIC was recorded, by repeated exposure. The developed PBM-resistant mutant acquired resistance to penicillin, cefoxitin, and ciprofloxacin. No clinical isolates were PVP-I-resistant while 48.5% were PBM-resistant. PBM-resistant isolates were more significantly detected among multidrug-resistant isolates. PVP-I subinhibitory concentrations (» and ½ of MIC) completely inhibited biofilm formation and significantly reduced hemolysin activity (7% and 0.28%, respectively). However, subinhibitory concentrations of PBM caused moderate reduction in biofilm activity and non-significant reduction in hemolysin activity. The ½ MIC of PVP-I significantly reduced the expression of hla, ebps, eno, fib, icaA, and icaD genes. The virulence of the biocide-resistant mutant was similar to that of parent strain. CONCLUSION: PVP-I is a highly recommended antiseptic for use in healthcare settings to control the evolution of high-risk clones. Exposure to PVP-I causes no resistance-development risk in S. aureus, with virulence inhibition by subinhibitory concentrations. Also, special protocols need to be followed during PBM use in hospitals to avoid the selection of resistant strains.


Assuntos
Desinfetantes , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Povidona-Iodo/farmacologia , Antibacterianos/farmacologia , Virulência , 1-Propanol/farmacologia , Proteínas Hemolisinas/farmacologia , Farmacorresistência Bacteriana , Desinfetantes/farmacologia
13.
Langenbecks Arch Surg ; 396(7): 1055-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21116645

RESUMO

BACKGROUND AND AIMS: Ethanol- or 1-propanol-containing hand disinfectants are widely used as surgical hand antisepsis. The primary objective of this study was to investigate transdermal absorption of ethanol and 1-propanol from combination of 45% ethanol and 18% 1-propanol with skin protecting ingredients (Softa-Man®) within 1 h after application in comparison to the absorption of these alcohols from the product in the absence of the cosmetic additives. The secondary objective was to evaluate the dermal tolerability. MATERIALS AND METHODS: Following the double-blind, randomized cross-over design for this clinical trial, 20 ml of two different alcohol-containing disinfectants was applied with a 200-cm(2) gauze swab on a skin area, identical in size and location, of 14 healthy volunteers for 10 min to investigate the absorption rate of ethanol and 1-propanol. Local dermal tolerability was evaluated using a four-point erythema scale. RESULTS: No clinically relevant dermal absorption, with respect to ethanol and 1-propanol, could be observed within 1 h after application. Disinfectant-related mild local skin erythema was observed in three cases. CONCLUSION: The use of the tested formulations containing ethanol and 1-propanol can be considered as safe. The tested formulation containing skin protecting additives (Softa-Man®) does not result in more alcoholic absorption than the formulation without protective additives.


Assuntos
1-Propanol/farmacocinética , Anti-Infecciosos Locais/farmacocinética , Etanol/farmacocinética , Absorção Cutânea/efeitos dos fármacos , 1-Propanol/farmacologia , Adulto , Antropometria , Anti-Infecciosos Locais/farmacologia , Índice de Massa Corporal , Estudos Cross-Over , Método Duplo-Cego , Etanol/farmacologia , Desinfecção das Mãos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
14.
Georgian Med News ; (195): 58-61, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21778543

RESUMO

The aim of the study was the investigation of age-related functional alterations of adrenoreceptors and the effect of agonist and antagonist drugs on age related adrenoreceptor activity in erythrocyte membrane. The impact of isopropanol and propanol on functional activity ß- adrenergic receptors in red blood cell membrane were studied in 50 practically healthy men--volunteers. (I group--75-89 years old, II group--22-30 years old). The EPR signals S1 and S2 were registered in red blood cell membrane samples after incubation with isopropanol and propanol respectively. It was found that decreasing sensitivity (functional activity) of red blood cells membrane adrenoreceptors comes with aging (S1old

Assuntos
Membrana Eritrocítica/metabolismo , Receptores Adrenérgicos beta/metabolismo , 1-Propanol/farmacologia , 2-Propanol/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Membrana Eritrocítica/efeitos dos fármacos , Humanos , Masculino , Adulto Jovem
15.
Int J Mol Sci ; 11(4): 1403-12, 2010 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-20480026

RESUMO

The inducible Mar phenotype of Escherichia coli is associated with increased tolerance to multiple hydrophobic antibiotics as well as some highly hydrophobic organic solvents such as cyclohexane, mediated mainly through the AcrAB/TolC efflux system. The influence of water miscible alcohols ethanol and 1-propanol on a Mar constitutive mutant and a mar deletion mutant of E. coli K-12, as well as the corresponding strains carrying the additional acrAB deletion, was investigated. In contrast to hydrophobic solvents, all strains were killed in exponential phase by 1-propanol and ethanol at rates comparable to the parent strain. Thus, the Mar phenotype does not protect E. coli from killing by these more polar solvents. Surprisingly, AcrAB does not contribute to an increased alcohol tolerance. In addition, sodium salicylate, at concentrations known to induce the mar operon, was unable to increase 1-propanol or ethanol tolerance. Rather, the toxicity of both solvents was increased in the presence of sodium salicylate. Collectively, the results imply that the resilience of E. coli to water miscible alcohols, in contrast to more hydrophobic solvents, does not depend upon the AcrAB/TolC efflux system, and suggests a lower limit for substrate molecular size and functionality. Implications for the application of microbiological systems in environments containing high contents of water miscible organic solvents, e.g., phage display screening, are discussed.


Assuntos
Álcoois/farmacologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Lipoproteínas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas Repressoras/metabolismo , 1-Propanol/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Tolerância a Medicamentos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Etanol/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Fenótipo , Proteínas Repressoras/genética , Salicilato de Sódio/química , Salicilato de Sódio/farmacologia , Solventes/química
16.
Int J Biol Macromol ; 146: 687-691, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31846662

RESUMO

The response of porcine pancreatic elastase (PPE) to propanol was examined by various techniques including UV-vis spectrophotometry, spectrofluorometry and circular dichroism, as well as molecular docking and molecular simulation. These techniques were used to investigate the structural changes and elastase activity in the presence of propanol. This work was performed at three temperatures of 303, 313 and 323 K, with the pH value of 8.5 (Tris buffer). The results of the UV-vis spectrophotometry indicated the transfer of tryptophan to an environment with low hydrophobicity. Fluorescence measurements also revealed the quenching of fluorescence intensity was induced by propanol, and dynamic quenching was the proposed quenching mechanism. Kinetic studies also suggested the inhibitory effect (noncompetitive) of propanol on elastase. Further, Circular Dichroism (CD) spectra showed that propanol caused slight alterations in the secondary structures of PPE (0.3% increase for the α-helix and 0.5% decrease for the ß-sheet). Addition of propanol decreased the Tm (Melting Temperature) parameter from 332.8 K to 330.1 K.


Assuntos
1-Propanol/química , 1-Propanol/farmacologia , Simulação de Acoplamento Molecular/métodos , Elastase Pancreática/química , Elastase Pancreática/efeitos dos fármacos , Elastase Pancreática/metabolismo , Animais , Fenômenos Químicos , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Cinética , Desnaturação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Espectrometria de Fluorescência , Suínos , Temperatura , Triptofano/metabolismo
17.
Biochim Biophys Acta ; 1778(4): 1148-53, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18258179

RESUMO

Membrane viscosity is a key parameter in cell physiology, cell function, and cell signaling. The most common methods to measure changes in membrane viscosity are fluorescence recovery after photobleaching (FRAP) and fluorescence anisotropy. Recent interest in a group of viscosity sensitive fluorophores, termed molecular rotors, led to the development of the highly membrane-compatible (2-carboxy-2-cyanovinyl)-julolidine farnesyl ester (FCVJ). The purpose of this study is to examine the fluorescent behavior of FCVJ in model membranes exposed to various agents of known influence on membrane viscosity, such as alcohols, dimethyl sulfoxide (DMSO), cyclohexane, cholesterol, and nimesulide. The influence of key agents (propanol and cholesterol) was also examined using FRAP, and backcalculated viscosity change from FCVJ and FRAP was correlated. A decrease of FCVJ emission was found with alcohol treatment (with a strong dependency on the chain length and concentration), DMSO, and cyclohexane, whereas cholesterol and nimesulide led to increased FCVJ emission. With the exception of nimesulide, FCVJ intensity changes were consistent with expected changes in membrane viscosity. A comparison of viscosity changes computed from FRAP and FCVJ led to a very good correlation between the two experimental methods. Since molecular rotors, including FCVJ, allow for extremely easy experimental methods, fast response time, and high spatial resolution, this study indicates that FCVJ may be used to quantitatively determine viscosity changes in phospholipid bilayers.


Assuntos
Ésteres/metabolismo , Bicamadas Lipídicas/metabolismo , Quinolizinas/metabolismo , Sesquiterpenos/metabolismo , 1-Propanol/farmacologia , Colesterol/metabolismo , Ésteres/química , Recuperação de Fluorescência Após Fotodegradação , Quinolizinas/química , Sesquiterpenos/química , Solventes , Sulfonamidas/farmacologia , Viscosidade/efeitos dos fármacos
18.
Biomacromolecules ; 10(4): 707-11, 2009 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-19249855

RESUMO

Microbial polyhydroxyalkanoates (PHA) were proposed for the first time as a new type of biofuel. In this paper, poly-R-3-hydroxybutyrate (PHB) and medium chain length PHA (mcl PHA) were, respectively, esterified to become R-3-hydroxybutyrate methyl ester (3HBME) and medium chain length hydroxyalkanoate methyl ester (3HAME) via acid-catalyzed hydrolysis. The recovery percentages of 3HBME and 3HAME were 52 and 65%, respectively. The purities of 3HBME and 3HAME were 97 and 96%, respectively. Combustion heats of 3HBME, 3HAME, ethanol, n-propanol, n-butanol, 0(#) diesel, 90(#) gasoline, and 3HBME-based and 3HAME-based blended fuels were investigated and compared, respectively. It was found that 3HBME and 3HAME had combustion heats valuing 20 and 30 KJ/g, respectively. Ethanol has a combustion heat of 27 KJ/g, while addition of 10% 3HBME or 3HAME enhanced the combustion heat of ethanol to 30 and 35 KJ/g, respectively. The addition of 3HBME or 3HAME into n-propanol and n-butanol led to a slight reduction of their combustion heats. Combustion heats of blended fuels 3HBME/diesel or 3HBME/gasoline and of 3HAME/diesel or 3HAME/gasoline were lower than that of the pure diesel or gasoline. It was roughly estimated that the production cost of PHA-based biofuels should be around US$1200 per ton.


Assuntos
Ácido 3-Hidroxibutírico/química , Fontes Geradoras de Energia , Ésteres/química , Poli-Hidroxialcanoatos/química , Pseudomonas putida/química , 1-Butanol/farmacologia , 1-Propanol/farmacologia , Etanol/farmacologia , Fermentação , Gasolina , Temperatura Alta , Pseudomonas putida/crescimento & desenvolvimento
19.
Eur J Clin Microbiol Infect Dis ; 28(11): 1357-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19669812

RESUMO

We studied the effect of a 1-min hand wash on the bacterial hand flora in two consecutive surgical hand disinfection procedures. A propanol-based hand rub (PBHR; Sterillium) and n-propanol (60%, v/v) were tested in a Latin-square design according to EN 12791 in four variations. The reference alcohol was always applied for 3 min after a 1-min hand wash (variation 1). The PBHR was applied for 1.5 min (first application) or 0.5 min (second application). Variation 2 included a 1-min hand wash before both applications, variation 3 included the hand wash before application 1, in variation 4 hands were not washed at all before application. Pre- and post-values were obtained according to EN 12791. The reference disinfection reduced bacteria by 2.99 log(10) (immediate efficacy) and 2.22 log(10) after 3 h. The second reference disinfection reduced bacteria by 0.95 log(10) (immediate efficacy) and 0.68 log(10) after 3 h. The PBHR always yielded an equivalent reduction with and without a preceding hand wash (p > 0.05; Friedman test). A 1-min hand wash before application of the PBHR did not significantly change its efficacy for surgical hand disinfection in two consecutive surgical procedures of 3 h.


Assuntos
1-Propanol/farmacologia , Bactérias/isolamento & purificação , Desinfetantes/farmacologia , Desinfecção das Mãos/métodos , Mãos/microbiologia , Contagem de Colônia Microbiana , Humanos , Fatores de Tempo
20.
J Appl Genet ; 50(3): 301-10, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19638689

RESUMO

During fermentation, yeast cells are exposed to a number of stresses -- such as high alcohol concentration, high osmotic pressure, and temperature fluctuation - so some overlap of mechanisms involved in the response to these stresses has been suggested. To identify the genes required for tolerance to alcohol (ethanol, methanol, and 1-propanol), heat, osmotic stress, and oxidative stress, we performed genome-wide screening by using 4828 yeast deletion mutants. Our screens identified 95, 54, 125, 178, 42, and 30 deletion mutants sensitive to ethanol, methanol, 1-propanol, heat, NaCl, and H2O2, respectively. These deleted genes were then classified based on their cellular functions, and cross-sensitivities between stresses were determined. A large number of genes involved in vacuolar H(+)-ATPase (V-ATPase) function, cytoskeleton biogenesis, and cell wall integrity, were required for tolerance to alcohol, suggesting their protective role against alcohol stress. Our results revealed a partial overlap between genes required for alcohol tolerance and those required for thermotolerance. Genes involved in cell wall integrity and the actin cytoskeleton are required for both alcohol tolerance and thermotolerance, whereas the RNA polymerase II mediator complex seems to be specific to heat tolerance. However, no significant overlap of genes required for osmotic stress and oxidative stress with those required for other stresses was observed. Interestingly, although mitochondrial function is likely involved in tolerance to several stresses, it was found to be less important for thermotolerance. The genes identified in this study should be helpful for future research into the molecular mechanisms of stress response.


Assuntos
DNA Fúngico/genética , Regulação Fúngica da Expressão Gênica/genética , Genoma Fúngico/genética , Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , 1-Propanol/farmacologia , DNA Fúngico/efeitos dos fármacos , Etanol/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genoma Fúngico/efeitos dos fármacos , Estudo de Associação Genômica Ampla , Peróxido de Hidrogênio/farmacologia , Metanol/farmacologia , Pressão Osmótica/fisiologia , Estresse Oxidativo/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Deleção de Sequência/efeitos dos fármacos , Deleção de Sequência/genética
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