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1.
Environ Monit Assess ; 196(6): 521, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714584

RESUMO

The transport sector is considered the largest contributor of air pollutants in urban areas, mainly on-road vehicles, affecting the environment and human health. Bahía Blanca is a medium-sized Latin American city, with high levels of traffic in the downtown area during peak hours. In this regard, it is necessary to analyze air pollution using an air quality model considering that there are no air pollutant measurements in the central area. Furthermore, this type of study has not been carried out in the region and since the city is expected to grow, it is necessary to evaluate the current situation in order to make effective future decisions. In this sense, the AERMOD model (US-EPA version) and the RLINE source type were used in this work. This study analyzes the variations of pollutant concentrations coming from mobile sources in Bahía Blanca's downtown area, particularly carbon monoxide (CO) and nitrogen oxides (NOx) during the period Jul-2020 to Jun-2022. It is interesting to note the results show the maximum concentration values detected are not directly associated with maximum levels of vehicle flow or emission rates, which highlights the importance of meteorological parameters in the modeling. In addition, alternative scenarios are proposed and analyzed from a sustainable approach. Regarding the scenario analysis, it can be concluded that diesel vehicles have a large influence on NOx emissions. Moreover, restrictions as strict as those proposed for a Low Emission Zone would be less applicable in the city than alternative temporary measures that modify traffic at peak hours.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monóxido de Carbono , Cidades , Monitoramento Ambiental , Emissões de Veículos , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Emissões de Veículos/análise , Monóxido de Carbono/análise , Óxidos de Nitrogênio/análise , América Latina , Modelos Teóricos , Material Particulado/análise
2.
Chemosphere ; 358: 142198, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697566

RESUMO

In the electrical industry, there are many hazardous gases that pollute the environment and even jeopardize human health, so timely detection and effective control of these hazardous gases is of great significance. In this work, the gas-sensitive properties of Pd-modified g-C3N4 interface for each hazardous gas molecule were investigated from a microscopic viewpoint, taking the hazardous gases (CO, NOx) that may be generated in the power industry as the detection target. Then, the performance of Pd-modifiedg-C3N4 was evaluated for practical applications as a gas sensor material. Novelly, an unconventional means was designed to briefly predict the effect of humidity on the adsorption properties of this sensor material. The final results found that Pd-modified g-C3N4 is most suitable as a potential gas-sensitizing material for NO2 gas sensors, followed by CO. Interestingly, Pd-modified g-C3N4 is less suitable as a potential gas-sensitizing material for NO gas sensors, but has the potential to be used as a NO cleaner (adsorbent). Unconventional simulation explorations of humidity effects show that in practical applications Pd-modified g-C3N4 remains a promising material for gas sensing in specific humidity environments. This work reveals the origin of the excellent properties of Pd-modified g-C3N4 as a gas sensor material and provides new ideas for the detection and treatment of these three hazardous gases.


Assuntos
Poluentes Atmosféricos , Paládio , Poluentes Atmosféricos/análise , Paládio/química , Adsorção , Água/química , Monitoramento Ambiental/métodos , Gases/análise , Umidade , Monóxido de Carbono/análise , Nitrilas/química , Nitrilas/análise
3.
J Environ Manage ; 359: 121017, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38718602

RESUMO

Energy transition currently brings focus on fuel cell micro-combined heat and power (mCHP) systems for residential uses. The two main technologies already commercialized are the Proton Exchange Membrane Fuel Cells (PEMFCs) and Solid Oxide Fuel Cells (SOFCs). The pollutant emissions of one system of each technology have been tested with a portable probe both in laboratory and field-test configurations. In this paper, the nitrogen oxides (NOx), sulphur dioxide (SO2), and carbon monoxide (CO) emission levels are compared to other combustion technologies such as a recent Euro 6 diesel automotive vehicle, a classical gas condensing boiler, and a gas absorption heat pump. At last, a method of converting the concentration of pollutants (in ppm) measured by the sensors into pollutant intensity per unit of energy (in mg/kWh) is documented and reported. This allows for comparing the pollutant emissions levels with relevant literature, especially other studies conducted with other measuring sensors. Both tested residential fuel cell technologies fed by natural gas can be considered clean regarding SO2 and NOx emissions. The CO emissions can be considered quite low for the tested SOFC and even nil for the tested PEMFC. The biggest issue of natural gas fuel cell technologies still lies in the carbon dioxide (CO2) emissions associated with the fossil fuel they consume. The gas absorption heat pump however shows worse NOx and CO levels than the classical gas condensing boiler. At last, this study illustrates that the high level of hybridization between a fuel cell and a gas boiler may be responsible for unexpected ON/OFF cycling behaviours and therefore prevent both sub-systems from operating as optimally and reliably as they would have as standalone units.


Assuntos
Poluentes Atmosféricos , Óxidos de Nitrogênio , Poluentes Atmosféricos/análise , Óxidos de Nitrogênio/análise , Monóxido de Carbono/análise , Dióxido de Enxofre/análise , Benchmarking , Emissões de Veículos/análise , Monitoramento Ambiental/métodos
4.
Nat Commun ; 15(1): 4151, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755154

RESUMO

Atmospheric methane oxidizing bacteria (atmMOB) constitute the sole biological sink for atmospheric methane. Still, the physiological basis allowing atmMOB to grow on air is not well understood. Here we assess the ability and strategies of seven methanotrophic species to grow with air as sole energy, carbon, and nitrogen source. Four species, including three outside the canonical atmMOB group USCα, enduringly oxidized atmospheric methane, carbon monoxide, and hydrogen during 12 months of growth on air. These four species exhibited distinct substrate preferences implying the existence of multiple metabolic strategies to grow on air. The estimated energy yields of the atmMOB were substantially lower than previously assumed necessary for cellular maintenance in atmMOB and other aerobic microorganisms. Moreover, the atmMOB also covered their nitrogen requirements from air. During growth on air, the atmMOB decreased investments in biosynthesis while increasing investments in trace gas oxidation. Furthermore, we confirm that a high apparent specific affinity for methane is a key characteristic of atmMOB. Our work shows that atmMOB grow on the trace concentrations of methane, carbon monoxide, and hydrogen present in air and outlines the metabolic strategies that enable atmMOB to mitigate greenhouse gases.


Assuntos
Monóxido de Carbono , Hidrogênio , Metano , Oxirredução , Metano/metabolismo , Monóxido de Carbono/metabolismo , Hidrogênio/metabolismo , Atmosfera/química , Ar , Nitrogênio/metabolismo , Gases de Efeito Estufa/metabolismo
5.
PLoS One ; 19(5): e0302653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748750

RESUMO

Out-of-hospital cardiac arrest (OHCA) affects over 360,000 adults in the United States each year with a 50-80% mortality prior to reaching medical care. Despite aggressive supportive care and targeted temperature management (TTM), half of adults do not live to hospital discharge and nearly one-third of survivors have significant neurologic injury. The current treatment approach following cardiac arrest resuscitation consists primarily of supportive care and possible TTM. While these current treatments are commonly used, mortality remains high, and survivors often develop lasting neurologic and cardiac sequela well after resuscitation. Hence, there is a critical need for further therapeutic development of adjunctive therapies. While select therapeutics have been experimentally investigated, one promising agent that has shown benefit is CO. While CO has traditionally been thought of as a cellular poison, there is both experimental and clinical evidence that demonstrate benefit and safety in ischemia with lower doses related to improved cardiac/neurologic outcomes. While CO is well known for its poisonous effects, CO is a generated physiologically in cells through the breakdown of heme oxygenase (HO) enzymes and has potent antioxidant and anti-inflammatory activities. While CO has been studied in myocardial infarction itself, the role of CO in cardiac arrest and post-arrest care as a therapeutic is less defined. Currently, the standard of care for post-arrest patients consists primarily of supportive care and TTM. Despite current standard of care, the neurological prognosis following cardiac arrest and return of spontaneous circulation (ROSC) remains poor with patients often left with severe disability due to brain injury primarily affecting the cortex and hippocampus. Thus, investigations of novel therapies to mitigate post-arrest injury are clearly warranted. The primary objective of this proposed study is to combine our expertise in swine models of CO and cardiac arrest for future investigations on the cellular protective effects of low dose CO. We will combine our innovative multi-modal diagnostic platform to assess cerebral metabolism and changes in mitochondrial function in swine that undergo cardiac arrest with therapeutic application of CO.


Assuntos
Monóxido de Carbono , Modelos Animais de Doenças , Animais , Suínos , Monóxido de Carbono/farmacologia , Monóxido de Carbono/metabolismo , Parada Cardíaca/terapia , Parada Cardíaca Extra-Hospitalar/terapia , Masculino , Reanimação Cardiopulmonar/métodos
6.
Environ Monit Assess ; 196(6): 545, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38740605

RESUMO

In Tunisia, urban air pollution is becoming a bigger problem. This study used a combined strategy of biomonitoring with lichens and satellite mapping with Sentinel-5 satellite data processed in Google Earth Engine (GEE) to assess the air quality over metropolitan Tunis. Lichen diversity was surveyed across the green spaces of the Faculty of Science of Tunisia sites, revealing 15 species with a predominance of pollution-tolerant genera. The Index of Atmospheric Purity (IAP) calculated from the lichen data indicated poor air quality. Spatial patterns of pollutants sulfur dioxide (SO2), ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO), and aerosol index across Greater Tunis were analyzed from Sentinel-5 datasets on the GEE platform. The higher values of these indices in the research area indicate that it may be impacted by industrial activity and highlight the considerable role that vehicle traffic plays in air pollution. The results of the IAP, IBL, and the combined ground-based biomonitoring and satellite mapping techniques confirm poor air quality and an environment affected by atmospheric pollutants which will enable proactive air quality management strategies to be put in place in Tunisia's rapidly expanding cities.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Líquens , Ozônio , Dióxido de Enxofre , Líquens/química , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Tunísia , Ozônio/análise , Dióxido de Enxofre/análise , Dióxido de Nitrogênio/análise , Cidades , Imagens de Satélites , Monóxido de Carbono/análise
7.
Microb Cell Fact ; 23(1): 125, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698392

RESUMO

BACKGROUND: The facultatively anaerobic thermophile Parageobacillus thermoglucosidasius is able to produce hydrogen gas (H2) through the water-gas shift (WGS) reaction. To date this process has been evaluated under controlled conditions, with gas feedstocks comprising carbon monoxide and variable proportions of air, nitrogen and hydrogen. Ultimately, an economically viable hydrogenogenic system would make use of industrial waste/synthesis gases that contain high levels of carbon monoxide, but which may also contain contaminants such as H2, oxygen (O2) and other impurities, which may be toxic to P. thermoglucosidasius. RESULTS: We evaluated the effects of synthesis gas (syngas) mimetic feedstocks on WGS reaction-driven H2 gas production by P. thermoglucosidasius DSM 6285 in small-scale fermentations. Improved H2 gas production yields and faster onset towards hydrogen production were observed when anaerobic synthetic syngas feedstocks were used, at the expense of biomass accumulation. Furthermore, as the WGS reaction is an anoxygenic process, we evaluated the influence of O2 perturbation on P. thermoglucosidasius hydrogenogenesis. O2 supplementation improved biomass accumulation, but reduced hydrogen yields in accordance with the level of oxygen supplied. However, H2 gas production was observed at low O2 levels. Supplementation also induced rapid acetate consumption, likely to sustain growth. CONCLUSION: The utilisation of anaerobic syngas mimetic gas feedstocks to produce H2 and the relative flexibility of the P. thermoglucosidasius WGS reaction system following O2 perturbation further supports its applicability towards more robust and continuous hydrogenogenic operation.


Assuntos
Fermentação , Hidrogênio , Oxigênio , Hidrogênio/metabolismo , Oxigênio/metabolismo , Monóxido de Carbono/metabolismo , Anaerobiose , Biomassa , Gases/metabolismo
8.
J Am Heart Assoc ; 13(9): e032067, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38700010

RESUMO

BACKGROUND: Doxorubicin and other anthracyclines are crucial cancer treatment drugs. However, they are associated with significant cardiotoxicity, severely affecting patient care and limiting dosage and usage. Previous studies have shown that low carbon monoxide (CO) concentrations protect against doxorubicin toxicity. However, traditional methods of CO delivery pose complex challenges for daily administration, such as dosing and toxicity. To address these challenges, we developed a novel oral liquid drug product containing CO (HBI-002) that can be easily self-administered by patients with cancer undergoing doxorubicin treatment, resulting in CO being delivered through the upper gastrointestinal tract. METHODS AND RESULTS: HBI-002 was tested in a murine model of doxorubicin cardiotoxicity in the presence and absence of lung or breast cancer. The mice received HBI-002 twice daily before doxorubicin administration and experienced increased carboxyhemoglobin levels from a baseline of ≈1% to 7%. Heart tissue from mice treated with HBI-002 had a 6.3-fold increase in CO concentrations and higher expression of the cytoprotective enzyme heme oxygenase-1 compared with placebo control. In both acute and chronic doxorubicin toxicity scenarios, HBI-002 protected the heart from cardiotoxic effects, including limiting tissue damage and cardiac dysfunction and improving survival. In addition, HBI-002 did not compromise the efficacy of doxorubicin in reducing tumor volume, but rather enhanced the sensitivity of breast 4T1 cancer cells to doxorubicin while simultaneously protecting cardiac function. CONCLUSIONS: These findings strongly support using HBI-002 as a cardioprotective agent that maintains the therapeutic benefits of doxorubicin cancer treatment while mitigating cardiac damage.


Assuntos
Antibióticos Antineoplásicos , Monóxido de Carbono , Cardiotoxicidade , Doxorrubicina , Proteínas de Membrana , Animais , Doxorrubicina/toxicidade , Monóxido de Carbono/metabolismo , Antibióticos Antineoplásicos/toxicidade , Feminino , Administração Oral , Camundongos , Heme Oxigenase-1/metabolismo , Cardiopatias/induzido quimicamente , Cardiopatias/prevenção & controle , Cardiopatias/metabolismo , Cardiopatias/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Carboxihemoglobina/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos , Humanos
9.
Undersea Hyperb Med ; 51(1): 37-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38615351

RESUMO

Carbon monoxide (CO) and cyanide poisoning are frequent causes of morbidity and mortality in cases of house and industrial fires. The 14th edition of guidelines from the Undersea and Hyperbaric Medical Society does not recommend hyperbaric oxygen (HBO2) treatment in those patients who have suffered a cardiac arrest and had to receive cardiopulmonary resuscitation. In this paper, we describe the case of a 31-year-old patient who received HBO2 treatment in the setting of cardiac arrest and survived.


Assuntos
Intoxicação por Monóxido de Carbono , Parada Cardíaca , Oxigenoterapia Hiperbárica , Humanos , Adulto , Intoxicação por Monóxido de Carbono/complicações , Intoxicação por Monóxido de Carbono/terapia , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Oxigênio , Monóxido de Carbono
10.
Microb Biotechnol ; 17(4): e14452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568755

RESUMO

Gas fermentation of CO2 and H2 is an attractive means to sustainably produce fuels and chemicals. Clostridium autoethanogenum is a model organism for industrial CO to ethanol and presents an opportunity for CO2-to-ethanol processes. As we have previously characterized its CO2/H2 chemostat growth, here we use adaptive laboratory evolution (ALE) with the aim of improving growth with CO2/H2. Seven ALE lineages were generated, all with improved specific growth rates. ALE conducted in the presence of 2% CO along with CO2/H2 generated Evolved lineage D, which showed the highest ethanol titres amongst all the ALE lineages during the fermentation of CO2/H2. Chemostat comparison against the parental strain shows no change in acetate or ethanol production, while Evolved D could achieve a higher maximum dilution rate. Multi-omics analyses at steady state revealed that Evolved D has widespread proteome and intracellular metabolome changes. However, the uptake and production rates and titres remain unaltered until investigating their maximum dilution rate. Yet, we provide numerous insights into CO2/H2 metabolism via these multi-omics data and link these results to mutations, suggesting novel targets for metabolic engineering in this bacterium.


Assuntos
Dióxido de Carbono , Clostridium , Proteoma , Dióxido de Carbono/metabolismo , Monóxido de Carbono/metabolismo , Hidrogênio/metabolismo , Fermentação , Etanol/metabolismo , Metaboloma
11.
BMC Pulm Med ; 24(1): 163, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570751

RESUMO

BACKGROUND: Observational studies have shown that smoking is related to the diffusing capacity of the lungs for carbon monoxide (DLCO) in individuals with idiopathic pulmonary fibrosis (IPF). Nevertheless, further investigation is needed to determine the causal effect between these two variables. Therefore, we conducted a study to investigate the causal relationship between smoking and DLCO in IPF patients using two-sample Mendelian randomization (MR) analysis. METHODS: Large-scale genome-wide association study (GWAS) datasets from individuals of European descent were analysed. These datasets included published lifetime smoking index (LSI) data for 462,690 participants and DLCO data for 975 IPF patients. The inverse-variance weighting (IVW) method was the main method used in our analysis. Sensitivity analyses were performed by MR‒Egger regression, Cochran's Q test, the leave-one-out test and the MR-PRESSO global test. RESULTS: A genetically predicted increase in LSI was associated with a decrease in DLCO in IPF patients [ORIVW = 0.54; 95% CI 0.32-0.93; P = 0.02]. CONCLUSIONS: Our study suggested that smoking is associated with a decrease in DLCO. Patients diagnosed with IPF should adopt an active and healthy lifestyle, especially by quitting smoking, which may be effective at slowing the progression of IPF.


Assuntos
Estudo de Associação Genômica Ampla , Fibrose Pulmonar Idiopática , Humanos , Fumar/efeitos adversos , Fumar/genética , Fumar Tabaco , Fibrose Pulmonar Idiopática/genética , Monóxido de Carbono
12.
Biol Pharm Bull ; 47(4): 868-871, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38644197

RESUMO

Restoration of blood flow in skeletal muscle after a prolonged period of ischemia induces muscular ischemia-reperfusion injury, leading to local injury/dysfunction in muscles followed by systemic inflammatory responses. However, preventive/curative agents for skeletal muscle ischemia injury are unavailable in clinics to date. Increasing evidence has validated that carbon monoxide (CO) prevents the progression of ischemia-reperfusion injury in various organs owing to its versatile bioactivity. Previously, we developed a bioinspired CO donor, CO-bound red blood cells (CO-RBC), which mimics the dynamics of RBC-associated CO in the body. In the present study, we have tested the therapeutic potential of CO-RBC in muscular injury/dysfunction and secondary systemic inflammation induced by skeletal muscle ischemia-reperfusion. The results indicate that CO-RBC rather than RBC alone suppressed elevation of plasma creatine phosphokinase, a marker of muscular injury, in rats subjected to both hind limbs ischemia-reperfusion. In addition, the results of the treadmill walking test revealed a significantly decreased muscular motor function in RBC-treated rats subjected to both hind limbs ischemia-reperfusion than that in healthy rats, however, CO-RBC treatment facilitated sustained muscular motor functions after hind limbs ischemia-reperfusion. Furthermore, CO-RBC rather than RBC suppressed the production of tumour necrosis factor (TNF)-α and interleukin (IL)-6, which were upregulated by muscular ischemia-reperfusion. Interestingly, CO-RBC treatment induced higher levels of IL-10 compared to saline or RBC treatments. Based on these findings, we suggest that CO-RBC exhibits a suppressive effect against skeletal muscle injury/dysfunction and systemic inflammatory responses after skeletal muscle ischemia-reperfusion.


Assuntos
Monóxido de Carbono , Inflamação , Músculo Esquelético , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Animais , Traumatismo por Reperfusão/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Masculino , Inflamação/tratamento farmacológico , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Ratos , Creatina Quinase/sangue , Membro Posterior/irrigação sanguínea , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/sangue , Interleucina-6/metabolismo , Interleucina-6/sangue
13.
Sci Rep ; 14(1): 8625, 2024 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616193

RESUMO

While particle therapy has been used for decades for cancer treatment, there is still a lack of information on the molecular mechanisms of biomolecules radiolysis by accelerated ions. Here, we examine the effects of accelerated protons on highly concentrated native myoglobin, by means of Fourier transform infrared and UV-Visible spectroscopies. Upon irradiation, the secondary structure of the protein is drastically modified, from mostly alpha helices conformation to mostly beta elements at highest fluence. These changes are accompanied by significant production of carbon monoxide, which was shown to come from heme degradation under irradiation. The radiolytic yields of formation of denatured protein, carbon monoxide, and of heme degradation were determined, and found very close to each other: G+denatured Mb ≈ G+CO ≈ G-heme = 1.6 × 10-8 ± 0.1 × 10-8 mol/J = 0.16 ± 0.01 species/100 eV. The denaturation of the protein to a beta structure and the production of carbon monoxide under ion irradiation are phenomena that may play an important role in the biological effects of ionizing radiation.


Assuntos
Mioglobina , Prótons , Monóxido de Carbono , Géis , Heme
14.
J Chem Phys ; 160(16)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38666573

RESUMO

Cooperativity is essential for the proper functioning of numerous proteins by allosteric interactions. Hemoglobin from Scapharca inaequivalvis (HbI) is a homodimeric protein that can serve as a minimal unit for studying cooperativity. We investigated the structural changes in HbI after carbon monoxide dissociation using time-resolved resonance Raman spectroscopy and observed structural rearrangements in the Fe-proximal histidine bond, the position of the heme in the pocket, and the hydrogen bonds between heme and interfacial water upon ligand dissociation. Some of the spectral changes were different from those observed for human adult hemoglobin due to differences in subunit assembly and quaternary changes. The structural rearrangements were similar for the singly and doubly dissociated species but occurred at different rates. The rates of the observed rearrangements indicated that they occurred synchronously with subunit rotation and are influenced by intersubunit coupling, which underlies the positive cooperativity of HbI.


Assuntos
Heme , Hemoglobinas , Scapharca , Scapharca/química , Hemoglobinas/química , Heme/química , Animais , Análise Espectral Raman , Humanos , Monóxido de Carbono/química , Ligação de Hidrogênio
15.
Nitric Oxide ; 146: 31-36, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574950

RESUMO

Carbon monoxide (CO) poisoning is a leading cause of poison-related morbidity and mortality worldwide. By binding to hemoglobin and other heme-containing proteins, CO reduces oxygen delivery and produces tissue damage. Prompt treatment of CO-poisoned patients is necessary to prevent acute and long-term complications. Oxygen therapy is the only available treatment. Visible light has been shown to selectively dissociate CO from hemoglobin with high efficiency without affecting oxygen affinity. Pulmonary phototherapy has been shown to accelerate the rate of CO elimination in CO poisoned mice and rats when applied directly to the lungs or via intra-esophageal or intra-pleural optical fibers. The extracorporeal removal of CO using a membrane oxygenator with optimal characteristic for blood exposure to light has been shown to accelerate the rate of CO illumination in rats with or without lung injury and in pigs. The development of non-invasive techniques to apply pulmonary phototherapy and the development of a compact, highly efficient membrane oxygenator for the extracorporeal removal of CO in humans may provide a significant advance in the treatment of CO poisoning.


Assuntos
Intoxicação por Monóxido de Carbono , Fototerapia , Intoxicação por Monóxido de Carbono/terapia , Animais , Humanos , Fototerapia/métodos , Monóxido de Carbono
16.
Redox Biol ; 72: 103153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608580

RESUMO

Carbon monoxide (CO), a gaseous signaling molecule, has shown promise in preventing body weight gain and metabolic dysfunction induced by high fat diet (HFD), but the mechanisms underlying these effects are largely unknown. An essential component in response to HFD is the gut microbiome, which is significantly altered during obesity and represents a target for developing new therapeutic interventions to fight metabolic diseases. Here, we show that CO delivered to the gut by oral administration with a CO-releasing molecule (CORM-401) accumulates in faeces and enriches a variety of microbial species that were perturbed by a HFD regimen. Notably, Akkermansia muciniphila, which exerts salutary metabolic effects in mice and humans, was strongly depleted by HFD but was the most abundant gut species detected after CORM-401 treatment. Analysis of bacterial transcripts revealed a restoration of microbial functional activity, with partial or full recovery of the Krebs cycle, ß-oxidation, respiratory chain and glycolysis. Mice treated with CORM-401 exhibited normalization of several plasma and fecal metabolites that were disrupted by HFD and are dependent on Akkermansia muciniphila's metabolic activity, including indoles and tryptophan derivatives. Finally, CORM-401 treatment led to an improvement in gut morphology as well as reduction of inflammatory markers in colon and cecum and restoration of metabolic profiles in these tissues. Our findings provide therapeutic insights on the efficacy of CO as a potential prebiotic to combat obesity, identifying the gut microbiota as a crucial target for CO-mediated pharmacological activities against metabolic disorders.


Assuntos
Monóxido de Carbono , Dieta Hiperlipídica , Microbioma Gastrointestinal , Obesidade , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Obesidade/microbiologia , Monóxido de Carbono/metabolismo , Dieta Hiperlipídica/efeitos adversos , Administração Oral , Akkermansia/efeitos dos fármacos , Masculino , Fezes/microbiologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
17.
J Phys Chem A ; 128(17): 3370-3386, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38652083

RESUMO

Biomass reburning is an efficient and low-cost way to control nitric oxide (NO), and the abundant potassium (K) element in biomass affects the heterogeneous reaction between NO and biochar. Due to the incomplete simulation of the NO heterogeneous reduction reaction pathway at the molecular level and the unclear catalytic effect of K element in biochar, further research is needed on the possible next reaction and the influencing mechanism of the element. After the products of the existing reaction pathways are referenced, two reasonably simplified biochar structural models are selected as the basic reactants to study the microscopic mechanism for further NO heterogeneous reduction on the biochar surface before and after doping with the K atom based on density functional theory. In studying the two further NO heterogeneous reduction reaction pathways, we find that the carbon monoxide (CO) molecule fragment protrudes from the surface of biochar models with the desorption of N2 at the TS4 transition state, and the two edge types of biochar product models obtained by simulation calculation are Klein edge and ac56 edge observed in the experiment. In studying the catalytic effect of potassium in biochar, we find that the presence of K increases the heat release of adsorption of NO molecules, reduces the energy barrier of the rate-determining step in the nitrogen (N2) generation and desorption process (by 50.88 and 69.97%), and hinders the CO molecule from desorbing from the biochar model surface. Thermodynamic and kinetic analyses also confirm its influence. The study proves that the heterogeneous reduction reaction of four NO molecules on the surface of biochar completes the whole reaction process and provides a basic theoretical basis for the emission of nitrogen oxides (NOx) during biomass reburning.


Assuntos
Carvão Vegetal , Teoria da Densidade Funcional , Óxido Nítrico , Potássio , Carvão Vegetal/química , Potássio/química , Óxido Nítrico/química , Oxirredução , Propriedades de Superfície , Adsorção , Modelos Químicos , Monóxido de Carbono/química
18.
Chemosphere ; 358: 142157, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679181

RESUMO

Microbial electrosynthesis (MES) is an electrically driven technology that can be used for converting CO/CO2 into chemicals. The unique electronic and substrate properties of CO make it an important research target for MES. However, CO can poison the cathode and increase the overpotential of hydrogen evolution reaction (HER), thus reducing the electron transfer rate via H2. This work evaluated the effect of an anti-CO HER catalyst on the performance of MES for CO/CO2 conversion. ZnMo-metal-organic framework (MOF) materials with different calcination temperatures were synthesized. ZnMo-MOF-800 with Mo2C nanoparticles as active centers exhibited excellent resistance to CO toxicity. It also obtained the highest hydrogen evolution and enhanced electron transfer rate in CO atmosphere. MES with ZnMo-MOF-800 cathode and Clostridium ljungdahlii as biocatalyst obtained 0.31 g L-1 d-1 acetate yield, 0.1 g L-1 d-1 butyrate yield, and 0.09 g L-1 d-1 2,3-butanediol yield in CO/CO2, while Pt/C only get 0.076 g L-1 d-1 acetate yield, 0.05 g L-1 d-1 butyrate yield and 0.02 g L-1 d-1 2,3-butanediol yield. ZnMo-MOF-800 was conducive to biofilm formation, enabling it to better resist CO toxicity. This work provides new opportunities for constructing a highly efficient cathode with an anti-CO hydrogen evolution catalyst to enhance CO/CO2 conversion in MES.


Assuntos
Dióxido de Carbono , Monóxido de Carbono , Hidrogênio , Estruturas Metalorgânicas , Hidrogênio/metabolismo , Hidrogênio/química , Dióxido de Carbono/química , Catálise , Estruturas Metalorgânicas/química , Eletrodos , Clostridium/metabolismo , Técnicas Eletroquímicas , Molibdênio/química , Zinco/química
19.
Chemosphere ; 357: 142048, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641295

RESUMO

The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P-N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity. The hollow dodecahedral ZIF-67 has been used for smoke suppression catalysis, but the agglomeration phenomenon makes it inefficient. Hence, in this study, the adhesive properties of polydopamine (PDA) were utilized to assist the in-situ growth of ZIF-67. The results showed that the total smoke release rate of the treated FPUF was reduced by 40.5%. The toxic gases, such as carbon monoxide (CO), hydrogen cyanide, etc., also showed the same decreasing trend. What's more, the catalytic effect of ZIF-67 itself and the synergistic effect with LFPN gave FPUF great flame retardant and smoke inhibition properties. This novel FPUF provides a new reference for achieving smoke suppression and toxicity reduction.


Assuntos
Retardadores de Chama , Poliuretanos , Fumaça , Retardadores de Chama/toxicidade , Poliuretanos/química , Indóis/química , Incêndios/prevenção & controle , Polímeros/química , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/química , Monóxido de Carbono/química , Catálise , Imidazóis , Zeolitas
20.
Waste Manag ; 182: 250-258, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677142

RESUMO

Carbon monoxide (CO) formation has been observed during composting of various fractions of organic waste. It was reported that this production can be biotic, associated with the activity of microorganisms. However, there are no sources considering the microbial communities producing CO production in compost. This preliminary research aimed to isolate and identify microorganisms potentially responsible for the CO production in compost collected from two areas of the biowaste pile: with low (118 ppm) and high CO concentration (785 ppm). Study proved that all isolates were bacterial strains with the majority of rod-shaped Gram-positive bacteria. Both places can be inhabited by the same bacterial strains, e.g. Bacillus licheniformis and Paenibacillus lactis. The most common were Bacillus (B. licheniformis, B. haynesii, B. paralicheniformis, and B. thermolactis). After incubation of isolates in sealed bioreactors for 4 days, the highest CO levels in the headspace were recorded for B. paralicheniformis (>1000 ppm), B. licheniformis (>800 ppm), and G. thermodenitrificans (∼600 ppm). High CO concentrations were accompanied by low O2 (<6%) and high CO2 levels (>8%). It is recommended to analyze the expression of the gene encoding CODH to confirm or exclude the ability of the identified strains to convert CO2 to CO.


Assuntos
Monóxido de Carbono , Compostagem , Monóxido de Carbono/metabolismo , Monóxido de Carbono/análise , Microbiologia do Solo , Bacillus/metabolismo , Bacillus/genética , Bacillus/isolamento & purificação , Reatores Biológicos/microbiologia , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação
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