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1.
Can Vet J ; 65(3): 245-249, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38434162

RESUMO

Objective: Several skin preparation techniques are used in electrocardiogram (ECG) monitoring of horses. The objective of this study was to determine which methods produce the greatest signal quality using textile electrodes and standard silver/silver chloride (Ag/AgCl) electrodes. Animals and samples: Electrocardiogram data were collected using textile and Ag/AgCl electrodes simultaneously for 4 skin preparation techniques in 6 horses. Procedure: The effects of skin preparation (cleansing with isopropyl alcohol, with or without shaving the hair) and the effects of the application of a conductive gel were assessed using metrics of signal quality. Results: Shaving and cleansing with alcohol had no effect on signal quality for either electrode type. The Ag/AgCl electrodes contain a solid gel, and the application of additional gel did not affect signal quality. Data quality was significantly improved when gel was applied to textile electrodes. Furthermore, there was no difference in signal quality between electrode types when gel was used. Conclusion and clinical relevance: This study suggests that skin preparation by cleansing and/or shaving does not have a significant effect on equine ECG signal quality. When gel is used, textile electrodes are a practical alternative for Ag/AgCl electrodes, as they produce ECG recordings of the same quality.


Impact de la méthode de préparation de la peau sur la qualité de l'électrocardiogramme chez le cheval. Objectif: Plusieurs techniques de préparation de la peau sont utilisées lors de la surveillance électrocardiographique (ECG) des chevaux. L'objectif de cette étude était de déterminer quelles méthodes produisent la meilleure qualité de signal en utilisant des électrodes textiles et des électrodes standard argent/chlorure d'argent (Ag/AgCl). Animaux et échantillons: Les données d'électrocardiogramme ont été obtenues simultanément à l'aide d'électrodes textiles et d'électrodes Ag/AgCl pour 4 techniques de préparation cutanée chez 6 chevaux. Procédure: Les effets de la préparation de la peau (nettoyage à l'alcool isopropylique, avec ou sans rasage des cheveux) et les effets de l'application d'un gel conducteur ont été évalués à l'aide de métriques de qualité du signal. Résultats: Le rasage et le nettoyage à l'alcool n'ont eu aucun effet sur la qualité du signal pour les deux types d'électrodes. Les électrodes Ag/AgCl contiennent un gel solide et l'application de gel supplémentaire n'a pas affecté la qualité du signal. La qualité des données a été considérablement améliorée lorsque le gel a été appliqué sur des électrodes textiles. De plus, il n'y avait aucune différence dans la qualité du signal entre les types d'électrodes lorsque du gel était utilisé. Conclusion et pertinence clinique: Cette étude suggère que la préparation de la peau par nettoyage et/ou rasage n'a pas d'effet significatif sur la qualité du signal ECG équin. Lorsque du gel est utilisé, les électrodes textiles constituent une alternative pratique aux électrodes Ag/AgCl, car elles produisent des enregistrements ECG de même qualité.(Traduit par Dr Serge Messier).


Assuntos
2-Propanol , Eletrocardiografia , Compostos de Prata , Animais , Cavalos , Eletrocardiografia/veterinária , Etanol
2.
Cutis ; 113(1): 48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38478938

RESUMO

Readily available and comparatively inexpensive, the common alcohol swab can aid dermatologists in everything from diagnosis to preoperative and postoperative care. The 70% isopropyl alcohol swab can aid in the accurate diagnosis of lesions and skin conditions, identification of biopsy sites, and disinfection.


Assuntos
2-Propanol , Pele , Humanos , Desinfecção
3.
World J Microbiol Biotechnol ; 40(3): 96, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349591

RESUMO

The preservation of drug stability in biological evidence during the processes of collection and storage poses a substantial obstacle to the progress of forensic investigations. In conjunction with other constituents, the microorganisms present in the samples play a vital role in this investigation. The present investigation employed the high-performance liquid chromatography (HPLC) technique to assess the stability of (1R,2 S)-(-)-2-methylamino-1-phenyl-1-propanol hydrochloride in plasma and urine samples that were inoculated with Escherichia coli. These samples were subjected to storage conditions of 37 °C for 48 h and - 20 °C for a duration of 6 months. Minimal inhibitory concentration (MIC) and Minimal bactericidal concentration (MBC) of MPPH against E. coli were determined using microdilution method. The stability of MPPH in plasma and urine samples inoculated with E. coli was investigated using HPLC method. The results showed the MIC and MBC of MPPH were 87.5 ± 25 ppm and 175 ± 50 ppm, respectively. While MPPH remained stable in plasma for 48 h at 37 °C, it showed a notable decrease of about 11% in stability when stored in urine for the same period and temperature. From the beginning of the first month, a decrease in the stability of the compound appeared in all samples that were stored at - 20 °C, and the decrease reached 7% for plasma samples and about 11% for urine samples. The decrease in the stability reached its peak in the sixth month, reaching more than 30% and 70% of plasma and urine samples preserved at - 20 °C. This work concluded that E. coli can negatively affect the stability of MPPH in plasma and urine samples. This may lead to incorrect conclusions regarding the analysis of biological samples in criminal cases.


Assuntos
1-Propanol , Escherichia coli , Cromatografia Líquida de Alta Pressão , 2-Propanol , Testes de Sensibilidade Microbiana
4.
Anal Bioanal Chem ; 416(8): 1867-1881, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38349535

RESUMO

The sample preparation step is pivotal in glycoproteomic analysis. An effective approach in glycoprotein sample preparation involves enriching glycopeptides by solid-phase extraction (SPE) using polar stationary phases in hydrophilic interaction liquid chromatography (HILIC) mode. The aim of this work is to show how different experimental conditions influence the enrichment efficiency of glycopeptides from human immunoglobulin G (IgG) on an aminopropyl-modified SPE column. Different compositions of the elution solvent (acetonitrile, methanol, and isopropanol), along with varying concentrations of elution solvent acidifiers (formic and acetic acid), and different concentrations of acetonitrile for the conditioning and washing solvents (65%, 75%, and 85% acetonitrile) were tested to observe their effects on the glycopeptide enrichment process. Isopropanol proved less effective in enriching glycopeptides, while acetonitrile was the most efficient, with methanol in between. Higher formic acid concentrations in the elution solvent weakened the ionic interactions, particularly with sialylated glycopeptides. Substituting formic acid with acetic acid led to earlier elution of more glycopeptides. The acetonitrile concentration in conditioning and washing solutions played a key role; at 65% acetonitrile, glycopeptides were not retained on the SPE column and were detected in the flow-through fraction. Ultimately, it was proven that the enrichment method was applicable to human plasma samples, resulting in a significant decrease in the abundances of non-glycosylated peptides. To the best of our knowledge, this study represents the first systematic investigation into the impact of the mobile phase on glycopeptide enrichment using an aminopropyl-modified SPE column in HILIC mode. This study demonstrates the substantial impact of even minor variations in experimental conditions, which have not yet been considered in the literature, on SPE-HILIC glycopeptide enrichment. Consequently, meticulous optimization of these conditions is imperative to enhance the specificity and selectivity of glycoproteomic analysis, ensuring accurate and reliable quantification.


Assuntos
Formiatos , Glicopeptídeos , Metanol , Humanos , Glicopeptídeos/química , 2-Propanol , Cromatografia Líquida/métodos , Solventes , Imunoglobulina G/química , Interações Hidrofóbicas e Hidrofílicas , Extração em Fase Sólida/métodos , Acetonitrilas , Acetatos
5.
Chemosphere ; 352: 141307, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307338

RESUMO

The present study compares the effect of using different solvents on the electrochemical properties of the reduced TiO2 nanotubes (TiO2-rNTs) layered Ti/TiO2-rNTs/SnO2-Sb/PbO2 anodes. The electrodes are prepared using three different solvent-based precursors: (i) isopropanol, (ii) ethylene glycol and citric acid (Pechini method), and (iii) 2-hydroxyethylammonium acetate (2HEAA) ionic liquid (IL) via the thermal decomposition route. The decomposition mechanism of precursor solutions was explored using the thermogravimetric (TGA) analysis. Further, the physicochemical properties of the electrodes are examined using Field emission Scanning Electron microscopy (FE-SEM), X-ray diffraction spectroscopy (XRD), and X-ray photoelectron emission spectroscopy (XPS). The results revealed that solvents with higher viscosity and slower decomposition rates support better film uniformity and higher stability of the electrode. The TiO2 -rNTs bottom layer and PbO2 top layer helped obtain higher film stability, increased working potential window (2.2 V vs. SHE) of the electrode, and the repeatability of the results. The performance of different electrodes based on the precursor solution is found as IL â‰« Pechini > Isopropanol. 4-chlorophenol (4-CP) is used as a model pollutant to test the performance of IL-Ti/TiO2-rNTs/SnO2-Sb/PbO2 anode in an anodic oxidation (AO) coupled electro-Fenton (EF) treatment. Further, the reliability of the electrode is evaluated by mineralizing other persistent organic pollutants (POPs) like tetracyclin, phenol, 2-chlorophenol (2-CP), and 2,4-dichlorophenol (2,4-DCP). Under the optimized conditions, the proposed system was able to mineralize the tetracyclin, phenol, 2-CP, 2,4-DCP, and 4-CP up to 78.91, 82.07, 74.96, 78.78, and 69.3 %, respectively. Moreover, the degradation mechanism of chlorophenols is proposed.


Assuntos
Óxidos , Poluentes Químicos da Água , Óxidos/química , Poluentes Orgânicos Persistentes , 2-Propanol , Reprodutibilidade dos Testes , Titânio/química , Oxirredução , Fenóis , Fenol/química , Eletrodos , Solventes , Poluentes Químicos da Água/química
6.
Bioresour Technol ; 396: 130416, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316230

RESUMO

Isopropanol, a well-known biofuel, is a widely used precursor for chemical products that can replace nonrenewable petroleum energy. Here, engineered Corynebacterium glutamicum that can effectively utilize all xylose and glucose in agricultural waste rice straw to produce isopropanol was described. First, codon mutations were introduced into transporters and glycolytic-related genes to decrease the glucose preference of C. glutamicum. A more energetically favorable xylose oxidative pathway was constructed that replaced traditional xylose isomerization pathways, saving twice the number of enzymatic steps. A succinate auxiliary module was incorporated into the tricarboxylic acid cycle (TCA), connecting the xylose-utilized pathway with the isopropanol pathway to maximize xylose orientation towards the product. The final engineered strain successfully consumed 100 % of the xylose from NaOH-pretreated, enzyme-hydrolyzed rice straw and effectively synthesized 4.91 g/L isopropanol. This study showcases the successful conversion of agricultural waste into renewable energy, unveiling new possibilities for advancing biological fermentation technology.


Assuntos
Corynebacterium glutamicum , Oryza , Xilose/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Oryza/metabolismo , 2-Propanol , Biomassa , Glucose/metabolismo , Engenharia Metabólica , Fermentação
7.
BJS Open ; 8(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38364056

RESUMO

BACKGROUND: The application of antiseptic skin agents prior to incision minimizes the rate of surgical site infection. Despite their ubiquity, the optimal skin preparation agent remains uncertain. A retrospective economic analysis was conducted to complement the results from the NEWSkin Prep trial which prospectively compared three preparation agents. METHODS: A cost and cost-effectiveness analysis was performed from a healthcare service perspective to compare chlorhexidine with 70% ethanol, and aqueous povidone-iodine, against povidone-iodine with 70% ethanol. Resource use estimates accounted for hospital admissions, readmissions associated with surgical site infection, outpatient and general practitioner attendances, visits from community nurses and therapeutic consumables. The measure of effectiveness comprised the net difference in number of patients with surgical site infections per 1000 patients. Costs were compared using a two-sample Welch's t-test. Deterministic and probabilistic sensitivity analyses were performed to evaluate the incremental cost-effectiveness ratio. RESULTS: The null hypothesis that the mean costs for the trial arms were significantly different was not rejected (Welch's t-test P value: 0.771 for chlorhexidine with 70% ethanol against povidone-iodine with 70% ethanol; and 0.955 for aqueous povidone-iodine against povidone-iodine with 70% ethanol). Based on bootstrap averages, the chlorhexidine with 70% ethanol intervention generated 8.0 fewer surgical site infections per 1000 patients and net cost savings of €151,698 (Euros) per 1000 patients compared with povidone-iodine with 70% ethanol, and aqueous povidone-iodine produced a net cost saving of €37,494 per 1000 patients but generated an additional 11.6 surgical site infections per 1000 patients compared with povidone-iodine with 70% ethanol. The comparison of chlorhexidine with 70% ethanol to povidone-iodine with 70% ethanol was sensitive to the inclusion of cost outliers, while the comparison of aqueous povidone-iodine to povidone-iodine with 70% ethanol was sensitive to the estimated cost per surgical site infection. CONCLUSION: Based on the outcomes from the NEWSkin Prep study, this economic analysis found no definitive evidence in favour of any one of the study comparators. Future model-based economic analyses of alternative skin preparations should critically address the quality of evidence and integrate the results from the NEWSkin Prep study.


Assuntos
Anti-Infecciosos Locais , Povidona-Iodo , Humanos , Povidona-Iodo/uso terapêutico , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Clorexidina/uso terapêutico , Análise de Custo-Efetividade , Estudos Retrospectivos , Anti-Infecciosos Locais/uso terapêutico , Etanol , 2-Propanol/uso terapêutico
8.
J Adhes Dent ; 26(1): 11-18, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38240152

RESUMO

PURPOSE: To evaluate the effect of different lithium-disilicate (LiSi) glass-ceramic surface decontamination procedures on the shear bond strength (SBS) to resin cement. MATERIALS AND METHODS: Seventy CAD/CAM LiSi ceramic specimens (IPS e.max CAD, Ivoclar) were cut and sintered. Fifty specimens were treated with 5% hydrofluoric acid (HF) for 20 s, while 20 were left untreated. All 70 specimens were then contaminated with human saliva and try-in silicone paste. The following surface cleaning methods were investigated (n = 10): C: water rinsing (control); PA: 37% H3PO4 etching for 20 s; E: 70% ethanol applied for 20 s; CP: cleaning paste (Ivoclean, Ivoclar) brushed for 20 s; HFSEP: self-etching ceramic primer (Monobond Etch&Prime, Ivoclar) rubbed for 20 s; HF: 5% HF applied for 20 s or no HF etching prior to contamination; SEP: self-etching ceramic primer rubbed for 20 s and no HF etching prior to contamination. Composite cylinders were created and luted with an adhesive resin cement to the decontaminated surfaces. After storage for 24 h at 37°C, the SBS test was conducted. Two fractured specimens per group were observed under SEM to perform fractographic analysis. The data were statistically analyzed with p set at <0.05. RESULTS: The type of surface cleaning approach influenced bond strength (p < 0.001). HFSEP, SEP, and HF attained higher SBS (p < 0.001) compared to other groups. None of the approaches were able to completely remove contaminants from the ceramic surfaces. SEM images showed residual traces of contaminants on CP-treated surfaces. CONCLUSIONS: The self-etching ceramic primer enhanced bond strength to contaminated LiSi ceramic surfaces, irrespective of previous treatment with hydrofluoric acid.


Assuntos
Colagem Dentária , Cimentos de Resina , Humanos , Lítio , Ácido Fluorídrico , Propriedades de Superfície , Teste de Materiais , Porcelana Dentária , Cerâmica , 2-Propanol , Silanos
9.
N Engl J Med ; 390(5): 409-420, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294973

RESUMO

BACKGROUND: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture). METHODS: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications. RESULTS: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups. CONCLUSIONS: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).


Assuntos
Anti-Infecciosos Locais , Clorexidina , Fixação de Fratura , Fraturas Ósseas , Iodo , Infecção da Ferida Cirúrgica , Humanos , 2-Propanol/administração & dosagem , 2-Propanol/efeitos adversos , 2-Propanol/uso terapêutico , Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/efeitos adversos , Anti-Infecciosos Locais/uso terapêutico , Antissepsia/métodos , Canadá , Clorexidina/administração & dosagem , Clorexidina/efeitos adversos , Clorexidina/uso terapêutico , Etanol , Extremidades/lesões , Extremidades/microbiologia , Extremidades/cirurgia , Iodo/administração & dosagem , Iodo/efeitos adversos , Iodo/uso terapêutico , Cuidados Pré-Operatórios/efeitos adversos , Cuidados Pré-Operatórios/métodos , Pele/microbiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Fraturas Ósseas/cirurgia , Estudos Cross-Over , Estados Unidos
10.
Am J Ind Med ; 67(3): 200-213, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38192156

RESUMO

BACKGROUND: Worldwide, lung cancer is the second leading cause of cancer death in women. The present study explored associations between occupational exposures that are prevalent among women, and lung cancer. METHODS: Data from 10 case-control studies of lung cancer from Europe, Canada, and New Zealand conducted between 1988 and 2008 were combined. Lifetime occupational history and information on nonoccupational factors including smoking were available for 3040 incident lung cancer cases and 4187 controls. We linked each reported job to the Canadian Job-Exposure Matrix (CANJEM), which provided estimates of probability, intensity, and frequency of exposure to each selected agent in each job. For this analysis, we selected 15 agents (cleaning agents, biocides, cotton dust, synthetic fibers, formaldehyde, cooking fumes, organic solvents, cellulose, polycyclic aromatic hydrocarbons from petroleum, ammonia, metallic dust, alkanes C18+, iron compounds, isopropanol, and calcium carbonate) that had lifetime exposure prevalence of at least 5% in the combined study population. For each agent, we estimated lung cancer risk in each study center for ever-exposure, by duration of exposure, and by cumulative exposure, using separate logistic regression models adjusted for smoking and other covariates. We then estimated the meta-odds ratios using random-effects meta-analysis. RESULTS AND CONCLUSIONS: None of the agents assessed showed consistent and compelling associations with lung cancer among women. The following agents showed elevated odds ratio in some analyses: metallic dust, iron compounds, isopropanol, and organic solvents. Future research into occupational lung cancer risk factors among women should prioritize these agents.


Assuntos
Compostos de Ferro , Neoplasias Pulmonares , Doenças Profissionais , Exposição Ocupacional , Humanos , Feminino , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/induzido quimicamente , 2-Propanol , Canadá/epidemiologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Poeira/análise , Fatores de Risco , Solventes/toxicidade , Estudos de Casos e Controles , Doenças Profissionais/etiologia , Doenças Profissionais/induzido quimicamente
11.
J Hosp Infect ; 145: 210-217, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272126

RESUMO

BACKGROUND: Compliance with the recommended 30 s drying time of alcohol-based hand rub (ABHR) is often suboptimal. To increase hand hygiene compliance at a neonatal intensive care unit (NICU), we installed an Incubator Traffic Light (ITL) system which shows 'green light' to open incubator doors after the recommended drying time. AIM: To measure the impact of this visual feedback system on NICU healthcare professionals' compliance with the recommended ABHR drying time. METHODS: Ten traffic light systems were installed on incubators at a NICU, five of which provided visual feedback, and five, serving as a control group, did not provide visual feedback. During a two-month period, the systems measured drying time between the moment of dispensing ABHR and opening the incubator's doors. The drying times of the incubators were compared with and without feedback. FINDINGS: Of the 6422 recorded hand hygiene events, 658 were valid for data analysis. Compliance with correct drying time reached 75% (N = 397/526) for incubators equipped with visual feedback versus 36% (N = 48/132; P < 0.0001) for incubators lacking this feature. CONCLUSION: The ITL improves compliance with the recommended 30 s ABHR drying time in a NICU setting.


Assuntos
Infecção Hospitalar , Higiene das Mãos , Recém-Nascido , Humanos , Unidades de Terapia Intensiva Neonatal , Retroalimentação , Retroalimentação Sensorial , Fidelidade a Diretrizes , Etanol , 2-Propanol , Incubadoras , Desinfecção das Mãos , Infecção Hospitalar/prevenção & controle
12.
J Chromatogr A ; 1717: 464660, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38280361

RESUMO

High-performance liquid chromatography-based enantioseparation of newly prepared azole analogs of monoterpene lactones and amides was studied. Effects of additives and mobile phase composition were evaluated both in normal and polar organic modes. Applying amylose tris-(3,5-dimethylphenylcarbamate) selector in normal and polar organic modes acid and base additives were found to affect the peak profiles, without significantly influencing the enantiorecognition ability of the studied selector. In most cases, differences observed in retention times and enantioselectivities were lower than 10 and 20 % under normal phase and polar organic conditions, respectively. Under normal phase conditions decreased retention was observed for all the studied analytes with increased eluent polarity. Interestingly, enantioselectivity was only slightly (<10 %) influenced by the variation in the n-hexane/2-propanol ratio between 80/20 and 20/80 v/v. In polar organic mode, five different neat solvents (acetonitrile, methanol, ethanol, 1-propanol, and 2-propanol) were tested, and the best results were obtained with acetonitrile and ethanol in the case of Lux Amylose-1 column with enantioresolutions most often above 2. Based on results obtained with amylose and cellulose-based columns the amylose tris-(3,5-dimethylphenylcarbamate) selector is found to offer a superior performance both in normal and polar organic modes. When evaluating the possible effects of the selector immobilization, no striking differences were found in the normal phase. Usually, enantioselectivities and resolutions were higher (10-20 %), while retention factors of the first peaks were lower (20-30 %), on the coated-type column. In contrast, in polar organic mode, the retention characteristics and enantiorecognition ability of the coated and immobilized selectors were heavily affected by the nature of the polar solvent. Special attention has been paid to the history-dependent behavior of polysaccharide-based selectors. A confidence interval-based evaluation is suggested to help comparison of the histereticity observed in different systems. Several examples are shown to confirm that the recently discovered hysteresis is a common characteristic of polysaccharide-based selectors.


Assuntos
Amidas , Amilose , Cromatografia Líquida de Alta Pressão/métodos , Amilose/química , Lactonas , 2-Propanol/química , Monoterpenos , Polissacarídeos/química , Fenilcarbamatos/química , Solventes/química , Etanol , Acetonitrilas , Estereoisomerismo
13.
Anal Biochem ; 688: 115461, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38244751

RESUMO

To investigate the solvent effect on the detection of peptides and proteins, nanoelectrospray mass spectra were measured for mixtures of 1 % acetic acid and 5 × 10-6 M gramicidin S (G), ubiquitin (U), and cytochrome c (C) in water (W), methanol (MeOH), 1-propanol (1-PrOH), acetonitrile (AcN), and 2-propanol (2-PrOH). Although doubly protonated G (G2+) and multiply protonated U (Un+) and C (Cn+) were readily detected with a wide range of mixing ratios of W solutions for MeOH, 1-PrOH, and AcN, Cn+ was totally suppressed for the solutions with mixing ratios (v/v) of W/2-PrOH (50/50) and (70/30). However, denatured Cn+ started to be detected with W/2-PrOH (90/10) together with Gn+ (n = 1, 2) and native Un+ (n = 6-8). At the mixing ratio of W/2-PrOH (95/5), native Cn+ (n = 7-10) together with Gn+ (n = 1, 2) and native Un+ (n = 6-8) were detected with high ion intensities. The use of W/2-PrOH (95/5) is profitable because it enables the detection of native proteins with high detection sensitivities.


Assuntos
1-Propanol , 2-Propanol , Solventes , Proteínas , Espectrometria de Massas , Peptídeos , Água , Metanol
14.
Artigo em Inglês | MEDLINE | ID: mdl-38248538

RESUMO

Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas chromatography-mass spectrometry method has been developed to quantify alcohols and their oxidative products using isotope-labeled internal standards. The limit of detection (LOD) of the analytes in the developed method was 0.211 µg/mL for methanol, 0.158 µg/mL for ethanol, 0.157 µg/mL for isopropanol, 0.010 µg/mL for n-propanol, 0.157 µg/mL for acetone, and 0.209 µg/mL for acetaldehyde. The precision and accuracy of the method were evaluated, and the relative standard deviation percentages were found to be less than 3%. This work demonstrates the application of this method, specifically in quantifying the concentration of oxidative products of alcohol and other minor alcohols found in hand sanitizers, which have become an essential household item since the COVID-19 pandemic. Apart from the major components, the minor alcohols found in hand sanitizers include methanol, isopropanol, and n-propanol. The concentration range of these minor alcohols found in ethanol-based hand sanitizer samples was as follows: methanol, 0.000921-0.0151 mg/mL; isopropanol, 0.454-13.8 mg/mL; and n-propanol, 0.00474-0.152 mg/mL. In ethanol-based hand sanitizers, a significant amount of acetaldehyde (0.00623-0.231 mg/mL) was observed as an oxidation product, while in the isopropanol-based hand sanitizer, acetone (0.697 mg/mL) was observed as an oxidation product. The concentration of acetaldehyde in ethanol-based hand sanitizers significantly increased with storage time and temperature, whereas no such increase in acetone concentration was observed in isopropanol-based hand sanitizers with storage time and temperature. In two of the selected hand sanitizers, the acetaldehyde levels increased by almost 200% within a week when stored at room temperature. Additionally, exposing the hand sanitizers to a temperature of 45 °C for 24 h resulted in a 100% increase in acetaldehyde concentration. On the contrary, the acetone level remained constant upon the change in storage time and temperature.


Assuntos
Higienizadores de Mão , Metanol , Humanos , Acetaldeído , Acetona , 2-Propanol , 1-Propanol , Temperatura , Cromatografia Gasosa-Espectrometria de Massas , Pandemias , Etanol
15.
J Biomol Struct Dyn ; 42(3): 1191-1207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37254438

RESUMO

A new series of 1-((1-(4-substituted benzyl)-1H-1,2,3-triazol-4-yl)methoxy)-2-(2-substituted quinolin-4-yl)propan-2-ol (9a-x) have been synthesized. The newly synthesized 1,2,3-triazolyl-quinolinyl-propan-2-ol (9a-x) derivatives were screened for in vitro antimicrobial activity against M. tuberculosis H37Rv, E. coli, P. mirabilis, B. subtilis, and S. albus. Most of the compounds showed good to moderate antibacterial activity and all derivatives have shown excellent to good antitubercular activity with MIC 0.8-12.5 µg/mL. To know the plausible mode of action for antibacterial activity the docking study against DNA gyrase from M. tuberculosis and S. aureus was investigated. The compounds have shown significant docking scores in the range of -9.532 to -7.087 and -9.543 to -6.621 Kcal/mol with the DNA gyrase enzyme of S. aureus (PDB ID: 2XCT) and M. tuberculosis (PDB ID: 5BS8), respectively. Against the S. aureus and M. tuberculosis H37Rv strains, the compound 9 l showed good activity with MIC values of 62.5 and 3.33 µM. It also showed significant docking scores in both targets with -8.291 and -8.885 Kcal/mol, respectively. Molecular dynamics was studied to investigate the structural and dynamics transitions at the atomistic level in S. aureus DNA gyrase (2XCT) and M. tuberculosis DNA gyrase (5BS8). The results revealed that the residues in the active binding pockets of the S. aureus and M. tuberculosis DNA gyrase proteins that interacted with compound 9 l remained relatively consistent throughout the MD simulations and thus, reflected the conformation stability of the respective complexes. Thus, the significant antimicrobial activity of derivatives 9a-x recommended that these compounds could assist in the development of lead compounds to treat for bacterial infections.Communicated by Ramaswamy H. Sarma.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis , Tuberculose , Humanos , DNA Girase/metabolismo , Escherichia coli/metabolismo , Staphylococcus aureus , Simulação de Acoplamento Molecular , Anti-Infecciosos/farmacologia , Antituberculosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Mycobacterium tuberculosis/metabolismo , 2-Propanol , Testes de Sensibilidade Microbiana
16.
Dent Mater ; 40(1): 3-8, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37858419

RESUMO

OBJECTIVE: Inert surface of Polyetherketoneketone (PEKK) jeopardizes resin bonding. This study aimed to present a new adhesive protocol to improve PEKK bonding. METHODS: A total of 360 PEKK blocks were milled, polished (maximum roughness of 0.20 µm), and randomly assigned to groups. The new protocol was applied (n = 36) and compared to conventional treatments (no treatment; sandblasting (110-µm Al2O3 and silica); no adhesive; Visiolink (Bredent); and PEKKbond (AnaxDent)) (n = 36). For the new protocol, the surface was blasted (110 µm Al2O3 and 96% isopropyl alcohol at 60 psi), followed by 96% isopropyl alcohol washing, and air drying. PEKKbond was applied (dried for 3 min at 77 °C), followed by Visiolink (dried for 3 min at 60 °C); both light-cured for 3 min (800 mW/cm2). Preopaque (GC Europe) and Opaque (AnaxDent) were applied and light-cured (5 min). Morphological topography was analyzed, and flowable gingiva-colored composite (AnaxGum, AnaxDent) was bonded. All specimens were aged for 24 h and thermocycled (5000 cycles, 5-55 °C). Shear bond strength (SBS) was measured (MPa) and data were analyzed by two-way ANOVA, Tukey, and Weibull moduli estimation (α = 0.05). RESULTS: The highest SBS values were found in the new protocol (p < 0.05), regardless of aging. Thermocycling reduced SBS (p < 0.05), while Al2O3 and PEKKbond produced higher SBS values than silica and Visiolink, respectively (p < 0.05). SIGNIFICANCE: The new protocol strongly improves PEKK adhesiveness, and this can reflect in the longevity of prostheses.


Assuntos
2-Propanol , Colagem Dentária , Colagem Dentária/métodos , Cimentos de Resina/química , Cimentos Dentários , Propriedades de Superfície , Resistência ao Cisalhamento , Dióxido de Silício/química , Teste de Materiais
17.
Arch Dis Child Fetal Neonatal Ed ; 109(2): 202-210, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-37907266

RESUMO

OBJECTIVE: Catheter-related sepsis (CRS) is a major complication with significant morbidity and mortality. Evidence is lacking regarding the most appropriate antiseptic for skin disinfection before percutaneous central venous catheter (PCVC) insertion in preterm neonates. To inform the feasibility and design of a definitive randomised controlled trial (RCT) of two antiseptic formulations, we conducted the Antiseptic Randomised Controlled Trial for Insertion of Catheters (ARCTIC) feasibility study to assess catheter colonisation, sepsis, and skin morbidity. DESIGN: Feasibility RCT. SETTING: Two UK tertiary-level neonatal intensive care units. PATIENTS: Preterm infants born <34 weeks' gestation scheduled to undergo PCVC insertion. INTERVENTIONS: Skin disinfection with either 2% chlorhexidine gluconate (CHG)-aqueous or 2% CHG-70% isopropyl alcohol (IPA) before PCVC insertion and at removal. PRIMARY OUTCOME: Proportion in the 2% CHG-70% IPA arm with a colonised catheter at removal. MAIN FEASIBILITY OUTCOMES: Rates of: (1) CRS, catheter-associated sepsis (CAS), and CRS/CAS per 1,000 PCVC days; (2) recruitment and retention; (3) data completeness. SAFETY OUTCOMES: Daily skin morbidity scores recorded from catheter insertion until 48 hours post-removal. RESULTS: 116 babies were randomised. Primary outcome incidence was 4.1% (95% confidence interval: 0.9% to 11.5%). Overall catheter colonisation rate was 5.2% (5/97); CRS 2.3/1000 catheter days; CAS 14.8/1000 catheter days. Recruitment, retention and data completeness were good. No major antiseptic-related skin injury was reported. CONCLUSIONS: A definitive comparative efficacy trial is feasible, but the very low catheter colonisation rate would make a large-scale RCT challenging due to the very large sample size required. ARCTIC provides preliminary reassurance supporting potential safe use of 2% CHG-70% IPA and 2% CHG-aqueous in preterm neonates. TRIAL REGISTRATION NUMBER: ISRCTN82571474.


Assuntos
Anti-Infecciosos Locais , Infecções Relacionadas a Cateter , Cateterismo Venoso Central , Cateteres Venosos Centrais , Clorexidina/análogos & derivados , Sepse , Recém-Nascido , Humanos , Cateterismo Venoso Central/efeitos adversos , 2-Propanol , Desinfecção , Estudos de Viabilidade , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/prevenção & controle , Sepse/epidemiologia , Sepse/prevenção & controle
18.
Trans R Soc Trop Med Hyg ; 118(3): 178-189, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-37994919

RESUMO

BACKGROUND: Hand hygiene (HH) is a proven low-cost means to curtail the problem of hospital-acquired infection (HAI). However, a low HH compliance rate of 17.1% was found among surgical health workers at Ahmadu Bello University Teaching Hospital (ABUTH) in Zaria, Nigeria. METHODS: This was an intervention study conducted utilizing mixed methods to investigate the effectiveness of the World Health Organization (WHO) multimodal strategy to improve the HH compliance rate of doctors at ABUTH Zaria. The study was conducted between June and August 2022 and included delivering a behavioural change HH workshop to doctors followed by data collection in the surgical wards that had received environmental modification through the provision of an alcohol-based hand rub (ABHR), HH posters and nurses for visual and/or verbal reminders. RESULTS: The cumulative HH compliance rate was 69% (n=1774) and was significantly different from the baseline HH compliance rate of 17.1% (confidence interval 45.5 to 57.7, p<0.001). Observed HH was highest in the ward with both visual and verbal reminders (78%) and lowest (59%) where neither visual nor verbal reminders were provided (n=444 per ward). All respondents reported motivation to perform HH with the presence of ABHR. CONCLUSIONS: The WHO multimodal strategy is good for enhancing HH among health workers in the context of low- and middle-income countries. More research is needed to understand how much of a reduction in HAI is directly associated with efficient HH by health workers.


Assuntos
Infecção Hospitalar , Higiene das Mãos , Humanos , Centros de Atenção Terciária , Controle de Infecções/métodos , Nigéria , Infecção Hospitalar/prevenção & controle , Pessoal de Saúde , Etanol , 2-Propanol , Fidelidade a Diretrizes , Desinfecção das Mãos/métodos
19.
Am J Infect Control ; 52(2): 176-182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37598902

RESUMO

BACKGROUND: A significant reduction in bacterial growth on stethoscope membranes has been noticed after performing daily disinfection. Nevertheless, disinfection is rarely performed. We aimed to assess self-reported stethoscope disinfection practices among medical doctors, detect bacterial contamination on personal stethoscopes, and estimate the effectiveness of 70% ethanol as a stethoscope disinfecting agent. METHODS: To determine stethoscope disinfection practices, participants filled out a questionnaire (N = 47), followed by providing stethoscopes for bacterial analysis. Differences in bacterial contamination were observed through the self-reported frequency and method of stethoscope disinfection. The effect of disinfecting with 70% ethanol was evaluated by comparing the presence of bacterial growth before and after disinfection. RESULTS: The presence of bacterial growth was found in 78.7% of the stethoscope samples, with the median (interquartile range) number of colony-forming units at 25 (10-105). The frequency of disinfection greatly impacted the number of colony-forming units, and the method affected the presence of bacterial growth. Disinfection of stethoscope membranes using 70% ethanol resulted in a compelling 97.3% reduction of bacterial growth. CONCLUSIONS: Adequate stethoscope disinfection is highly efficient in reducing bacterial contamination and as such should be considered a critical step in hygienic practices.


Assuntos
Desinfecção , Estetoscópios , Humanos , Desinfecção/métodos , Estetoscópios/microbiologia , Estudos Transversais , Sérvia , Bactérias , 2-Propanol , Hospitais , Etanol , Serviço Hospitalar de Emergência , Contaminação de Equipamentos
20.
Dent Mater ; 40(3): 451-457, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38129193

RESUMO

OBJECTIVES: This study evaluated the impact of different solvents and UV post-curing times on properties of 3D printing resins for provisional restorations. METHODS: The post-processing methods were tested using two solvents (isopropyl alcohol or absolute ethanol) and three UV times (5, 10, or 30 min). The resins tested were Resilab 3D Temp, Printax Temp, and Prizma Bioprov. Microhardness (kgf/mm2), fracture toughness (KIC, MPa√m), surface roughness (Ra, µm), gloss (gloss units), and degree of CC conversion (%DC) were measured (n = 8). All response variables were collected from the same specimen. The specimens were 3D printed using an SLA/LCD printer (150° angulation, 50 µm layer thickness). Light exposure times were adjusted for each material, and the post-processing methods were applied using an all-in-one machine immediately after printing. Data were analyzed using Three-Way ANOVA (α = 0.05). RESULTS: Microhardness was affected by UV post-cure time and 3D resin. Resilab showed higher microhardness with isopropyl alcohol and 30-min UV time, while Printax had higher microhardness with absolute ethanol. KIC was influenced by solvent type, UV time, and 3D resin, with varying effects on different resins. Roughness was affected by 3D resin and UV time, but no significant differences were seen for Resilab or Prizma. Gloss was influenced by 3D resin, and for Prizma, it was lower with specific solvent/UV time combinations. DC was influenced by 3D resin, with each resin behaving differently. SIGNIFICANCE: Tailoring the combination of 3D resin, solvent washing type, and UV post-curing time is important to achieve optimal mechanical and aesthetic outcomes for restorations.


Assuntos
Resinas Compostas , Polímeros , Solventes , 2-Propanol , Etanol , Impressão Tridimensional , Teste de Materiais , Propriedades de Superfície
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