ABSTRACT
The study of microbial hydrocarbons removal is of great importance for the development of future bioremediation strategies. In this study, we evaluated the removal of a gaseous mixture containing toluene, m-xylene, ethylbenzene, cyclohexane, butane, pentane, hexane and heptane in aerated stirred bioreactors inoculated with Rhodococcus erythropolis and operated under non-sterile conditions. For the real-time measurement of hydrocarbons, a novel systematic approach was implemented using Selected-Ion Flow Tube Mass Spectrometry (SIFT-MS). The effect of the carbon source (â¼9.5 ppmv) on (i) the bioreactors' performance (BR1: dosed with only cyclohexane as a single hydrocarbon versus BR2: dosed with a mixture of the 8 hydrocarbons) and (ii) the evolution of microbial communities over time were investigated. The results showed that cyclohexane reached a maximum removal efficiency (RE) of 53% ± 4% in BR1. In BR2, almost complete removal of toluene, m-xylene and ethylbenzene, being the most water-soluble and easy-to-degrade carbon sources, was observed. REs below 32% were obtained for the remaining compounds. By exposing the microbial consortium to only the five most recalcitrant hydrocarbons, REs between 45% ± 5% and 98% ± 1% were reached. In addition, we observed that airborne microorganisms populated the bioreactors and that the type of carbon source influenced the microbial communities developed. The abundance of species belonging to the genus Rhodococcus was below 10% in all bioreactors at the end of the experiments. This work provides fundamental insights to understand the complex behavior of gaseous hydrocarbon mixtures in bioreactors, along with a systematic approach for the development of SIFT-MS methods.
Subject(s)
Biodegradation, Environmental , Bioreactors , Hydrocarbons , Rhodococcus , Rhodococcus/metabolism , Bioreactors/microbiology , Hydrocarbons/metabolism , Carbon/metabolism , Air Pollutants/metabolism , Air Pollutants/analysis , Mass Spectrometry , Toluene/metabolism , Xylenes/metabolism , Butanes/metabolism , Benzene Derivatives , PentanesABSTRACT
This study investigated the multiple herbicide resistance (MHR) mechanism of one Echinochloa crus-galli population that was resistant to florpyrauxifen-benzyl (FPB), cyhalofop-butyl (CHB), and penoxsulam (PEX). This population carried an Ala-122-Asn mutation in the acetolactate synthase (ALS) gene but no mutation in acetyl-CoA carboxylase (ACCase) and transport inhibitor response1 (TIR1) genes. The metabolism rate of PEX was 2-fold higher, and the production of florpyrauxifen-acid and cyhalofop-acid was lower in the resistant population. Malathion and 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) could reverse the resistance, suggesting that cytochrome P450 (CYP450) and glutathione S-transferase (GST) contribute to the enhanced metabolism. According to RNA-seq and qRT-PCR validation, two CYP450 genes (CYP71C42 and CYP71D55), one GST gene (GSTT2), two glycosyltransferase genes (rhamnosyltransferase 1 and IAAGLU), and two ABC transporter genes (ABCG1 and ABCG25) were induced by CHB, FPB, and PEX in the resistant population. This study revealed that the target mutant and enhanced metabolism were involved in the MHR mechanism in E. crus-galli.
Subject(s)
Cytochrome P-450 Enzyme System , Echinochloa , Herbicide Resistance , Herbicides , Mutation , Plant Proteins , Herbicide Resistance/genetics , Herbicides/pharmacology , Herbicides/metabolism , Echinochloa/genetics , Echinochloa/drug effects , Echinochloa/metabolism , Echinochloa/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Acetyl-CoA Carboxylase/genetics , Acetyl-CoA Carboxylase/metabolism , Plant Weeds/drug effects , Plant Weeds/genetics , Plant Weeds/metabolism , Acetolactate Synthase/genetics , Acetolactate Synthase/metabolism , Butanes , Nitriles , Sulfonamides , Uridine/analogs & derivativesABSTRACT
Volatile substance abuse is widespread among adolescents due to its easy availability and methods of consumption. Inhalant abuse represents a current problematic issue, causing significant morbidity and mortality due to direct toxicity on several target organs and displacement of gas which results in a lack of oxygen. This review aims to evaluate post-mortem and toxicological investigations in cases of suspected butane intoxication. We performed comprehensive research using the Preferred Reporting Items for Systematic Review (PRISMA) standards. Forty scientific papers fulfilled the inclusion criteria. A total of 58 cases of butane-related deaths were found. Among these, we found 11 cases of suicide (18%), 1 case of homicide (2%), 44 cases of accidental poisoning (76%), and 2 cases of work-related deaths (4%). Autopsy and post-mortem examinations were performed in 54 cases, whereas toxicological analyses were presented in 56 cases. In autopsy, pulmonary edema (51%) and poli-visceral congestion (59%) were the most common findings. When death by butane inhalation is hypothesized, autopsy and histological findings may be nonspecific, therefore toxicological investigations assume a crucial role along with attention to the methods used to collect biological samples.
Subject(s)
Autopsy , Butanes , Humans , Butanes/poisoning , Butanes/analysis , Cause of Death , Male , Adolescent , Homicide , Inhalant Abuse , Forensic Toxicology , Female , Pulmonary Edema/pathology , SuicideABSTRACT
Acetyl-CoA carboxylase (ACCase)-inhibiting herbicides are among the most commonly used herbicides to control grassy weeds, especially Leptochloa chinensis, in rice fields across China. Herein, we collected a suspected resistant (R) population of L. chinensis (HFLJ16) from Lujiang county in Anhui Province. Whole plant dose response tests showed that, compared with the susceptible (S) population, the R population showed high resistance to cyhalofop-butyl (22-fold) and displayed cross-resistance to metamifop (9.7-fold), fenoxaprop-P-ethyl (18.7-fold), quizalofop-P-ethyl (7.6-fold), clodinafop-propargyl (12-fold) and clethodim (8.4-fold). We detected an amino acid substitution (Cys-2088-Arg) in the ACCase of resistant L. chinensis. However, ACCase gene expression levels were not significantly different (P > 0.05) between R plants and S plants, without or with cyhalofop-butyl treatment. Furthermore, pretreatment with piperonyl butoxide (PBO, a cytochrome P450 monooxygenase (CYP450) inhibitor) or 4-chloro-7-nitrobenzoxadiazole (NBD-Cl, a glutathione-S-transferase (GST) inhibitor), inhibited the resistance of the R population to cyhalofop-butyl significantly (by approximately 60% and 26%, respectively). Liquid chromatography tandem mass spectrometry analysis showed that R plants metabolized cyhalofop-butyl and cyhalofop acid (its metabolite) significantly faster than S plants. Three CYP450 genes, one GST gene, and two ABC transporter genes were induced by cyhalofop-butyl and were overexpressed in the R population. Overall, GST-associated detoxification, CYP450 enhancement, and target-site gene mutation are responsible for the resistance of L. chinensis to cyhalofop-butyl.
Subject(s)
4-Chloro-7-nitrobenzofurazan , Acetyl-CoA Carboxylase , Butanes , Herbicides , Nitriles , Oxazoles , Propionates , Acetyl-CoA Carboxylase/metabolism , Plant Proteins/genetics , Poaceae/genetics , Poaceae/metabolism , Herbicides/pharmacology , Cytochrome P-450 Enzyme System/genetics , Mutation , Herbicide Resistance/geneticsABSTRACT
Volatile Solvents Abuse (VSA) poses major health risks, especially for young people and those living in precarious socio-economic conditions. Such substances can in fact bring about psychoactive effects such as euphoria, and even lead to sudden death from cardiac arrhythmias, respiratory depression, myocardial infarction, laryngospasm, encephalopathy, and rhabdomyolysis. The present case report is centered around a 23-year-old man who died in prison due to inhalation of a cooker gas mixture (n-butane, propane, and isobutane) inside a plastic bag. External examination and autopsy showed non-specific signs of asphyxia associated with edema and brain swelling. Histological signs of early myocardial damage and hypoxic-ischemic injury (HII) were highlighted in the brain and cerebellum, as well as activated macrophages and anthracotic-like material in the lungs. Toxicological investigations revealed the presence of propane, isobutane and n-butane in liquids and biological samples. Besides the cardiotoxic effect, there was an asphyctic component due to the plastic bag that may have facilitated death. The assessment of cerebral HII and cardiopulmonary damage in acute cases is very important to prove death by butane inhalation. In the forensic field, it may be useful to shed more light on intoxications, deaths, and butane encephalopathies, as the latter can be mistaken for a hypoxic-ischemic encephalopathy.
Subject(s)
Butanes , Death, Sudden , Humans , Male , Young Adult , Asphyxia/etiology , Asphyxia/pathology , Brain/pathology , Brain Edema/pathology , Butanes/poisoning , Butanes/adverse effects , Death, Sudden/etiology , Hypoxia-Ischemia, Brain/etiology , Hypoxia-Ischemia, Brain/pathology , Inhalant Abuse/complications , Lung/pathology , Myocardium/pathology , Propane/poisoning , Propane/adverse effectsABSTRACT
Volatile organic compounds (VOCs) have grown due to their crucial role in transitioning from invasive to noninvasive cancer diagnostic methods. This study aimed to assess the feasibility of the metal oxide biosensor platform using urine VOCs for detecting genitourinary cancers. Five different commercially available semiconductor sensors were chosen to detect specific VOCs (methane, iso-butane, hydrogen, ethanol, hydrogen sulfide, ammonia, toluene, butane, propane, trimethylamine, and methyl-mercaptan). Changes in electrical resistance due to temperature variations from the voltage heater were examined to characterize VOC metabolism. Logistic regression and ROC analysis were employed to evaluate potential urine VOCs for genitourinary cancer determination. This study involved 64 participants which were categorized into a cancer and a non-cancer group. The genitourinary cancer (confirmed by tissue pathology) comprised 32 patients, including renal cell carcinoma (3.1%), transitional cell carcinoma (46.9%), and prostate cancer (50%). The non-cancer comprised 32 patients, with 9 healthy subjects and 23 individuals with other genitourinary diseases. Results indicated that VOC sensors for methane, iso-butane, hydrogen, and ethanol, at a voltage heater of 2000 mV, demonstrated a significant predictive capability for genitourinary cancer with P = 0.013. The ROC of these biomarkers also indicated statistical significance in predicting the occurrence of the disease (P < 0.05). This report suggested that methane, iso-butane, hydrogen, and ethanol VOCs exhibited potential for diagnosing genitourinary cancer. Developing gas metal oxide sensors tailored to these compounds, and monitoring changes in electrical resistance, could serve as an innovative tool for identifying this specific type of cancer.
Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Volatile Organic Compounds , Male , Humans , Volatile Organic Compounds/analysis , Butanes , Ethanol , Hydrogen , Methane , OxidesABSTRACT
The short-chain gaseous alkanes (ethane, propane, and butane; SCGAs) are important components of natural gas, yet their fate in environmental systems is poorly understood. Microbially mediated anaerobic oxidation of SCGAs coupled to nitrate reduction has been demonstrated for propane, but is yet to be shown for ethane or butane-despite being energetically feasible. Here we report two independent bacterial enrichments performing anaerobic ethane and butane oxidation, respectively, coupled to nitrate reduction to dinitrogen gas and ammonium. Isotopic 13C- and 15N-labelling experiments, mass and electron balance tests, and metabolite and meta-omics analyses collectively reveal that the recently described propane-oxidizing "Candidatus Alkanivorans nitratireducens" was also responsible for nitrate-dependent anaerobic oxidation of the SCGAs in both these enrichments. The complete genome of this species encodes alkylsuccinate synthase genes for the activation of ethane/butane via fumarate addition. Further substrate range tests confirm that "Ca. A. nitratireducens" is metabolically versatile, being able to degrade ethane, propane, and butane under anoxic conditions. Moreover, our study proves nitrate as an additional electron sink for ethane and butane in anaerobic environments, and for the first time demonstrates the use of the fumarate addition pathway in anaerobic ethane oxidation. These findings contribute to our understanding of microbial metabolism of SCGAs in anaerobic environments.
Subject(s)
Ethane , Nitrates , Ethane/metabolism , Nitrates/metabolism , Propane/metabolism , Anaerobiosis , Bacteria/genetics , Bacteria/metabolism , Oxidation-Reduction , Butanes/metabolism , Gases/metabolism , Fumarates/metabolismABSTRACT
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate (ODHP) was extracted in a previous study from the culture broth of soil isolate Alcaligenes faecalis MT332429 and showed a promising antimycotic activity. This study was aimed to formulate ODHP loaded ß-cyclodextrins (CD) nanosponge (NS) hydrogel (HG) to control skin fungal ailments since nanosponges augment the retention of tested agents in the skin. Box-Behnken design was used to produce the optimized NS formulation, where entrapment efficiency percent (EE%), polydispersity index (PDI), and particle size (PS) were assigned as dependent parameters, while the independent process parameters were polyvinyl alcohol % (w/v %), polymer-linker ratio, homogenization time, and speed. The carbopol 940 hydrogel was then created by incorporating the nanosponges. The hydrogel fit Higuchi's kinetic release model the best, according to in vitro drug release. Stability and photodegradation studies revealed that the NS-HG remained stable under tested conditions. The formulation also showed higher in vitro antifungal activity against Candida albicans compared to the control fluconazole. In vivo study showed that ODHP-NS-HG increased survival rates, wound contraction, and healing of wound gap and inhibited the inflammation process compared to the other control groups. The histopathological examinations and Masson's trichrome staining showed improved healing and higher records of collagen deposition. Moreover, the permeability of ODHP-NS-HG was higher through rats' skin by 1.5-folds compared to the control isoconazole 1%. Therefore, based on these results, NS-HG formulation is a potential carrier for enhanced and improved topical delivery of ODHP. Our study is a pioneering research on the development of a formulation for ODHP produced naturally from soil bacteria. KEY POINTS: ⢠Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate was successfully formulated as a nanosponge hydrogel and statistically optimized. ⢠The new formula exhibited in vitro good stability, drug release, and higher antifungal activity against C. albicans as compared to the fluconazole. ⢠Ex vivo showed enhanced skin permeability, and in vivo analysis showed high antifungal activity as evidenced by measurement of various biochemical parameters and histopathological examination.
Subject(s)
Alcaligenes faecalis , Butanes , Hydrogels , Rats , Animals , Antifungal Agents/pharmacology , Fluconazole , Propionates , Candida albicans , Soil , Particle SizeABSTRACT
AIM: This study aimed to assess the efficacy and safety of prusogliptin (DBPR108), a novel and highly selective dipeptidyl peptidase-4 inhibitor, in individuals with type 2 diabetes who had not been using glucose-lowering agents regularly for the 8 weeks before the screening period. MATERIALS AND METHODS: In this multicentre, randomized, double-blind, phase 3 study, adult patients with type 2 diabetes were randomly assigned to receive either DBPR108 100 mg, sitagliptin 100 mg, or placebo once daily during the initial 24-week double-blind treatment period, followed by a 28-week open-label extension period during which all patients received DBPR108 100 mg once daily. The primary endpoint was the mean change in glycated haemoglobin (HbA1c) levels from baseline to week 24. RESULTS: In total, 766 patients were enrolled and received DBPR108 100 mg (n = 462), sitagliptin 100 mg (n = 152), or placebo (n = 152). The mean age of all patients was 54.3 ± 10.5 years, with 58% being men. The median duration of type 2 diabetes was 0.38 (0.02, 2.65) years, and the mean HbA1c (SD) at baseline was 7.94% (0.62), 7.88% (0.61) and 7.83% (0.59) for DBPR108, sitagliptin and placebo groups, respectively. At week 24, the least square mean (SE) changes from baseline in HbA1c were -0.63% (0.04%) for DBPR108, -0.60% (0.07%) for sitagliptin and -0.02% (0.07%) for placebo. The mean treatment difference between DBPR108 and placebo was -0.61% (95% CI -0.77% to -0.44%), and between DBPR108 and sitagliptin was -0.03% (95% CI -0.19% to 0.13%). These results indicate that DBPR108 was superior to placebo and non-inferior to sitagliptin. DBPR108 also significantly reduced fasting and postprandial plasma glucose levels and had little effect on body weight. The mean (SD) changes in HbA1c from baseline to week 52 were -0.50% (0.97%) for the DBPR108 group, -0.46% (0.96%) for the sitagliptin group and -0.41% (0.95%) for the placebo group. The incidence of adverse events was comparable across all three groups. CONCLUSIONS: DBPR108 showed superiority to placebo and non-inferiority to sitagliptin in terms of glycaemic control over the initial 24 weeks in treatment-naïve patients with type 2 diabetes. Furthermore, its efficacy was sustained for up to 52 weeks.
Subject(s)
Butanes , Diabetes Mellitus, Type 2 , Metformin , Nitriles , Pyrrolidines , Male , Adult , Humans , Middle Aged , Female , Glycated Hemoglobin , Drug Therapy, Combination , Hypoglycemic Agents/adverse effects , Sitagliptin Phosphate/adverse effects , Treatment Outcome , Double-Blind Method , Metformin/therapeutic useABSTRACT
Worldwide, various inhalants are widely abused for recreational purposes, with butane and propane emerging as among the most commonly misused volatile substances, posing a significant risk of sudden death. The rapid elimination and oxidation of these highly volatile compounds upon inhalation necessitate the identification of butane and propane along with their metabolites in biological samples. Hence, the primary objective of this study is twofold: firstly, to establish a method for analyzing butane, propane, and metabolites, and secondly, to demonstrate the detection window and exposure indicators associated with the inhalation of butane and propane. In pursuit of this objective, we developed analytical methods for the determination of isobutane, n-butane, propane, and their nine metabolites in both blood and urine. Headspace-gas chromatography-mass spectrometry (GC-MS) and solid-phase microextraction-GC-MS were employed for the analyses, demonstrating acceptable precision and accuracy. An animal study revealed that isobutane and n-butane were only detectable below the limit of quantification (LOQ) in rat blood 5 min after exposure. Meanwhile, the three major metabolites-2-methyl-2-propanol, 2-butanol, and 2-butanone-were observed 5 min after exposure but persisted in rat urine even 5 h post-exposure. Additionally, human urine samples identified other metabolites, including acetone, acetoin, and 2,3-butanediol isomers. The presence of specific metabolites corresponding to each inhalant confirmed the abuse of butane and propane. This comprehensive approach provides valuable insights into the detection and assessment of inhalation to these volatile substances.
Subject(s)
Inhalant Abuse , Humans , Rats , Animals , Propane/analysis , Gas Chromatography-Mass Spectrometry , Butanes/analysisABSTRACT
BACKGROUND: Recently, suspected cyhalofop-butyl-resistant populations of allohexaploid weed Echinochloa crus-galli var. crus-galli were discovered in rice fields in Aichi Prefecture, Japan. Analyzing the target-site ACCase genes of cyhalofop-butyl helps understand the resistance mechanism. However, in E. crus-galli, the presence of multiple ACCase genes and the lack of detailed gene investigations have complicated the analysis of target-site genes. Therefore, in this study, we characterized the herbicide response of E. crus-galli lines and thoroughly characterized the ACCase genes, including the evaluation of gene mutations in the ACCase genes of each line. RESULT: Four suspected resistant lines collected from Aichi Prefecture showed varying degrees of resistance to cyhalofop-butyl and other FOP-class ACCase inhibitors but were sensitive to herbicides with other modes of action. Through genomic analysis, six ACCase loci were identified in the E. crus-galli genome. We renamed each gene based on its syntenic relationship with other ACCase genes in the Poaceae species. RNA-sequencing analysis revealed that all ACCase genes, except the pseudogenized copy ACCase2A, were transcribed at a similar level in the shoots of E. crus-galli. Mutations known to confer resistance to FOP-class herbicides, that is W1999C, W2027C/S and I2041N, were found in all resistant lines in either ACCase1A, ACCase1B or ACCase2C. CONCLUSION: In this study, we found that the E. crus-galli lines were resistant exclusively to ACCase-inhibiting herbicides, with a target-site resistance mutation in the ACCase gene. Characterization of ACCase loci in E. crus-galli provides a basis for further research on ACCase herbicide resistance in Echinochloa spp. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Subject(s)
Butanes , Echinochloa , Herbicides , Nitriles , Echinochloa/genetics , Japan , Herbicides/pharmacology , Herbicide Resistance/genetics , MutationSubject(s)
Acetates , Odorants , Perfume , Databases, Chemical , Butanes , Perfume/toxicity , Registries , Risk AssessmentABSTRACT
Apoptosis is regulated by the BCL-2 family, which includes the anti-apoptotic and pro-apoptotic proteins (Bax, Bok, Bak, etc.). These proteins often interact in dimers and act as apoptotic switches. Anti-apoptotic proteins, such as BCL-2, block the functions of these pro-apoptotic proteins. The pro-apoptotic and anti-apoptotic protein-protein interactions must be inhibited to prevent tumor cells from escaping apoptosis. This method has been used to develop anticancer drugs by inhibiting BCL-2 with both natural and synthetic compounds. Metal-containing compounds were used as pharmaceuticals for human cancer patients for a long time, and cisplatin was the first candidate of this class. Drug design, however, needs to pay more attention to metal complexes. We have studied the X-ray crystal structure of the BCL-2 protein in detail and identified the hydrophobic nature of the site with two less solvent-accessible sites. Based on the hydrophobic nature of the compounds, 74 organometallic compounds with X-ray crystallographically characterized bioactivity (including anticancer activity) were selected from the Cambridge crystallographic database. For testing, molecular docking was used to determine which compound was most effective against the BCL-2 protein. Organometallic compounds (benzene)-chloro-(1-{[(9H-fluoren-2-yl)imino]methyl}naphthalen-2-olato)-ruthenium (2), (1-((1,1'-biphenyl)-4-yl)-2,3,4,5-tetramethylcyclopentadienyl)-chloro-(4,4'-dimethyl-2,2'-bipyridine)-rhodium hexafluorophosphate (37), (µ-1,1'-(butane-1,4-diyl)bis(3-oxy-2-methylpyridin-4(1H)-one))-dichloro-bis(pentamethyl-cyclopentadienyl)-di-rhodium tetrahydrate (46), (µ-1,1'-(butane-1,4-diyl)bis(3-oxy-2-methylpyridin-4(1H)-one))-dichloro-bis(pentamethyl-cyclopentadienyl)-di-iridium (47) etc are found to be important compounds in this study. The capability of different types of complex interactions was identified using Hirshfeld surface analysis of the complexes. A NCI plot was conducted to understand the nature of the interaction between complex amino acids and active-site amino acids. A DFT study was conducted to examine the stability and chemical reactivity of the selected complexes. Using this study, one suitable hydrophobic lead anti-cancer organometallic pharmaceutical was found that binds at the less solvent-accessible hydrophobic site of BCL-2.
Subject(s)
Organometallic Compounds , Rhodium , Humans , bcl-2-Associated X Protein/metabolism , Molecular Docking Simulation , Proto-Oncogene Proteins c-bcl-2/chemistry , Proto-Oncogene Proteins c-bcl-2/metabolism , Apoptosis Regulatory Proteins/chemistry , Apoptosis Regulatory Proteins/metabolism , Apoptosis/physiology , Organometallic Compounds/pharmacology , Amino Acids , Solvents , ButanesABSTRACT
Chibaite, a silica-framework structure with cage-like voids occupied by gaseous molecules, was found in marine sediments. Its formation age could be evaluated using electron spin resonance (ESR) if the radicals formed by natural radiation can be assumed to accumulate over time. To investigate whether hydrogen transfer reactions, where organic radicals withdraw hydrogen atoms from other molecules in adjacent cages, occur in chibaite and affect ESR dating, gamma-irradiated chibaite was measured by ESR. Methyl, ethyl, n-propyl, isopropyl, tert-butyl radicals and hydrogen atoms were created by gamma irradiation at 77 K. The amount of tert-butyl radicals increased around 240 K and the similar amount of the other organic radicals decreased simultaneously, implying that hydrogen transfer reactions occur between isobutane and the organic radicals in chibaite around 240 K and therefore would have no influence on ESR dating because the reactions are completed at the environmental temperature.
Subject(s)
Gases , Hydrogen , Background Radiation , Butanes , Electron Spin Resonance SpectroscopyABSTRACT
BACKGROUND: Butane is an aliphatic hydrocarbon used in various commercial products. While numerous reports of sudden cardiac-related deaths from butane inhalation have been described, butane-associated acute encephalopathy has rarely been reported. CASE PRESENTATION: A 38-year-old man presented with cognitive dysfunction after butane gas inhalation. Neuropsychological test results showed impairments in verbal and visual memory, and frontal executive function. Diffusion weighted MRI revealed symmetric high-signal changes in the bilateral hippocampus and globus pallidus. FDG-PET demonstrated decreased glucose metabolism in the bilateral precuneus and occipital areas and the left temporal region. At the 8-month follow-up, he showed still significant deficits in memory and frontal functions. Diffuse cortical atrophy with white matter hyperintensities and extensive glucose hypometabolism were detected on follow-up MRI and FDG-PET, respectively. Brain autopsy demonstrated necrosis and cavitary lesions in the globus pallidus. CONCLUSIONS: Only a few cases of butane encephalopathy have been reported to date. Brain lesions associated with butane encephalopathy include lesions in the bilateral thalamus, insula, putamen, and cerebellum. To the best of our knowledge, this is the first report on bilateral hippocampal and globus pallidal involvement in acute butane encephalopathy. The pathophysiology of central nervous system complications induced by butane intoxication is not yet fully understood. However, the direct toxic effects of butane or anoxic injury secondary to cardiac arrest or respiratory depression have been suggested as possible mechanisms of edematous changes in the brain after butane intoxication.
Subject(s)
Brain Diseases , Fluorodeoxyglucose F18 , Male , Humans , Adult , Autopsy , Neuroimaging , Brain/diagnostic imaging , Magnetic Resonance Imaging/methods , Brain Diseases/chemically induced , Brain Diseases/diagnostic imaging , Butanes , Neuropsychological TestsABSTRACT
BACKGROUND: Brass screens are considered an essential part of the safer drug smoking/inhalation supplies and are widely distributed by harm reduction programs in Canada. However, the use of commercially available steel wools as screens for smoking crack cocaine remains a common practice among people who smoke drugs in Canada. Use of these steel wool materials is associated with different adverse effects on health. This study aims to determine what changes folding and heating have on several filter materials, including brass screens and commercially available steel wool products, and examine the implications of these changes on health of people who smoke drugs. METHODS: This study investigated the microscopic differences, studied by optical and scanning electron microscopy, between four screen and four steel wool filter materials used in a simulated drug consumption process. New materials were manipulated, compacted into its own Pyrex® straight stem using a push stick and then heated with a butane lighter simulating a common method in preparing drugs for consumption. The materials were studied in the as-received (new), as-pressed (compressed and inserted into the stem tube but without heating) and as-heated (compressed and inserted into the stem tube and heated with a butane lighter) conditions. RESULTS: The steel wool materials with the smallest wire thicknesses were found to be the easiest to prepare for pipe use, but degrade significantly during shaping and heating, making them wholly unsuitable as a safe filter material. In contrast the brass and stainless steel screen materials remain mostly unchanged by the simulated drug consumption process. After the stainless steel pellet screen, the Brass Impact 2.0 screen material had the best characteristics of the materials tested due to its mesh wire diameter, pitch, alloy choice and its pre-strained state. CONCLUSION: Commonly used steel wool alternatives degrade during the handling and stem insertion, and heating the screens in the stem. Debris is generated by wool deformation on insertion and after heating that easily separates from the screen and can be inhaled during drug consumption. The brass and stainless steel screen materials are safer to use as they remain mostly stable during the simulated drug consumption process.
Subject(s)
Stainless Steel , Steel , Humans , Butanes , SmokingABSTRACT
Nitrate contamination has been commonly detected in water environments and poses serious hazards to human health. Previously methane was proposed as a promising electron donor to remove nitrate from contaminated water. Compared with pure methane, natural gas, which not only contains methane but also other short chain gaseous alkanes (SCGAs), is less expensive and more widely available, representing a more attractive electron source for removing oxidized contaminants. However, it remains unknown if these SCGAs can be utilized as electron donors for nitrate reduction. Here, two lab-scale membrane biofilm reactors (MBfRs) separately supplied with propane and butane were operated under oxygen-limiting conditions to test its feasibility of microbial nitrate reduction. Long-term performance suggested nitrate could be continuously removed at a rate of â¼40-50 mg N/L/d using propane/butane as electron donors. In the absence of propane/butane, nitrate removal rates significantly decreased both in the long-term operation (â¼2-10 and â¼4-9 mg N/L/d for propane- and butane-based MBfRs, respectively) and batch tests, indicating nitrate bio-reduction was driven by propane/butane. The consumption rates of nitrate and propane/butane dramatically decreased under anaerobic conditions, but recovered after resupplying limited oxygen, suggesting oxygen was an essential triggering factor for propane/butane-based nitrate reduction. High-throughput sequencing targeting 16S rRNA, bmoX and narG genes indicated Mycobacterium/Rhodococcus/Thauera were the potential microorganisms oxidizing propane/butane, while various denitrifiers (e.g. Dechloromonas, Denitratisoma, Zoogloea, Acidovorax, Variovorax, Pseudogulbenkiania and Rhodanobacter) might perform nitrate reduction in the biofilms. Our findings provide evidence to link SCGA oxidation with nitrate reduction under oxygen-limiting conditions and may ultimately facilitate the design of cost-effective techniques for ex-situ groundwater remediation using natural gas.
Subject(s)
Nitrates , Propane , Humans , Natural Gas , RNA, Ribosomal, 16S , Alkanes , Methane , Butanes , Oxidation-Reduction , Biofilms , Oxygen , Water , BioreactorsABSTRACT
Nanopesticides are considered to be a novel and efficient kind of tool for controlling pests in modern agriculture. Covalent organic frameworks (COFs), with high surface areas, ordered structures, and rich functional groups for loading pesticides, are a class of promising carrier materials that can be used to develop efficient nanopesticide delivery systems. However, until now, only a strong ionic interaction between the pesticide and COF can be utilized to achieve the combination between the pesticide and COF. On the basis of this method, charged pesticide molecules are the only choice for COF-based nanopesticides, which limits the exploitation. The way to load the uncharged pesticide molecules into COF still needs to be explored. Herein, in this research, we provided a commonly mild and high-efficacy strategy for loading an uncharged pesticide molecule into COF. The herbicide cyhalofop-butyl (CB), as a neutral model pesticide molecule, was loaded into the sphere COF (SCOF, a model COF synthesized at room temperature) without any ionic interaction via the host-guest strategy. The loading capacity of CB into SCOF (CB@SCOF) was determined at 57% (w/w). Smaller CB@SCOF particles (150-200 nm) can efficiently enter the weed leaves and stems, enhancing the accumulation of the effective concentration in weeds, thus increasing herbicidal activity, in comparison to CB emulsifiable (EC, micrometer scale). Furthermore, CB@SCOF had a solubilization effect for CB in water and can improve the photostability of CB. Thus, the CB-loaded COF nanosphere showed excellent herbicidal activities against the target weeds Echinochloa crus-galli and Leptochloa chinensis compared to commercial CB EC. In conclusion, this study also provides a mild and high-efficacy pesticide loading strategy for COFs. The constructed efficient delivery system and pesticide formulation containing herbicidal COF nanospheres exhibit great potential applications for controlling weeds in sustainable agriculture.
Subject(s)
Herbicides , Metal-Organic Frameworks , Pesticides , Herbicides/pharmacology , Metal-Organic Frameworks/pharmacology , Pesticides/pharmacology , Butanes , Plant WeedsABSTRACT
Antibacterial coatings on biomedical instruments are of great interest because they can suppress bacterial colonization on these instruments. In this study, antibacterial polymeric thin coatings were deposited on teflon substrates using atmospheric pressure plasma polymerization from a propane-butane mixture. The plasma polymerization was performed by means of surface dielectric barrier discharge burning in nitrogen at atmospheric pressure. The chemical composition of plasma polymerized propane-butane films was studied by energy-dispersive X-ray spectroscopy (EDX) and FTIR. The film surface properties were studied by SEM and by surface energy measurement. The EDX analysis showed that the films consisted of carbon, nitrogen and oxygen from ambient air. The FTIR analysis confirmed, in particular, the presence of alkyl, nitrile, acetylene, imide and amine groups. The deposited films were hydrophilic with a water contact angle in the range of 13-23°. The thin film deposited samples were highly active against both S. aureus and E. coli strains in general. On the other hand, the films were cytocompatible, reaching more than 80% of the cell viability threshold compared to reference polystyrene tissue.
Subject(s)
Propane , Staphylococcus aureus , Escherichia coli , Nitrogen , Atmospheric Pressure , Anti-Bacterial Agents/pharmacology , ButanesABSTRACT
BACKGROUND: This study examine the histochemical and histomorphological effect of 1-isothiocyanato-4-methyl sulfonyl butane (SFN) on cisplatin (CP) induced testicular alteration and cholesterol homeostasis. MATERIALS AND METHODS: Ninety adult-male Sprague-Dawley rats were randomized into nine groups of ten (n=10) rats each. Group A (control) received normal saline, group B received a single dose of 10mg/Kg body weight (bwt) CP (i.p.), group C received 50mg/Kg bwt of SFN, group D received 100mg/Kg bwt of SFN, group E received 10mg/Kg bwt CP and 50mg/Kg bwt of SFN, group F received 10mg/Kg bwt CP and 100mg/Kg bwt of SFN, group G received 10mg/Kg bwt CP and 50mg/Kg bwt vitamin C, group H received 50mg/Kg bwt of SFN and 10mg/Kg bwt CP, group I received 100mg/Kg bwt of SFN and 10mg/Kg bwt CP. The procedure lasted for 56 days. Testicular histomorphology and histochemistry, testicular testosterone, sperm parameters, total antioxidant status (TSA), total oxidant status (TOS), oxidative stress index (OSI), and serum lipid profile were examined. RESULTS: Cisplatin decrease intra-testicular testosterone, sperm quality, and expression of glycogen and increases testicular TOS and OSI, serum lipid profile, collagen, and disruption of germinal epithelium. However, the intervention of SFN reversed the effect of CP on testes' weight and volume, DSP, ESP, testosterone production, TAS, TOS, and OSI. Histoarchitectecture showing normal seminiferous tubules and even distribution of glycogen and collagen fibers. CONCLUSION: Treatment with SFN ameliorate CP-induced testicular toxicity by reversing the cytotoxic mechanisms of CP.