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As an emerging environmental contaminant, antibiotic resistance genes (ARGs) in tap water have attracted great attention. Although studies have provided ARG profiles in tap water, research on their abundance levels, composition characteristics, and potential threat is still insufficient. Here, 9 household tap water samples were collected from the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) in China. Additionally, 75 sets of environmental sample data (9 types) were downloaded from the public database. Metagenomics was then performed to explore the differences in the abundance and composition of ARGs. 221 ARG subtypes consisting of 17 types were detected in tap water. Although the ARG abundance in tap water was not significantly different from that found in drinking water plants and reservoirs, their composition varied. In tap water samples, the three most abundant classes of resistance genes were multidrug, fosfomycin and MLS (macrolide-lincosamide-streptogramin) ARGs, and their corresponding subtypes ompR, fosX and macB were also the most abundant ARG subtypes. Regarding the potential mobility, vanS had the highest abundance on plasmids and viruses, but the absence of key genes rendered resistance to vancomycin ineffective. Generally, the majority of ARGs present in tap water were those that have not been assessed and are currently not listed as high-threat level ARG families based on the World Health Organization Guideline. Although the current potential threat to human health posed by ARGs in tap water is limited, with persistent transfer and accumulation, especially in pathogens, the potential danger to human health posed by ARGs should not be ignored.
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Agua Potable , Farmacorresistencia Microbiana , Metagenómica , Farmacorresistencia Microbiana/genética , Agua Potable/microbiología , China , Monitoreo del Ambiente , Antibacterianos/farmacología , Microbiología del AguaRESUMEN
OBJECTIVE: Blood flow sensitivity is a crucial metric for appraising the effectiveness of color Doppler flow imaging (CDFI). Color Doppler velocity maps based on classic autocorrelation techniques are widely used in clinical practice. However, these techniques often produce twinkling artifacts in noisy regions due to the inherent randomness of noise phases. To mitigate artifacts and improve image quality, Power Mask (PoM) technology becomes imperative. Nevertheless, PoM technology unintentionally filters out small flow signals that have similar power and frequency characteristics to noise signals, thereby reducing the imaging system's sensitivity to flow. Approach: To address this issue, a novel Flow Recycling Algorithm (FRA) based on phase anomaly is introduced in this study. This algorithm, excavating small flow signals from noise, aims to enhance the small flow signals with low-velocity by the phase characteristics of the color Doppler flow information. Main results: Experiments in multi-organ imaging have shown that the FRA-CDFI approach is more effective in suppressing twinkling artifacts in noisy regions, preserving intricate small flow signals, and markedly improving small blood flow sensitivity. This novel approach provides adequate technical support for clinical ultrasound imaging of organs with dense small blood vessels, such as the brain, kidneys, liver, and more. Significance: As a novel post-processing method, FRA-CDFI holds significant potential for future deployment in clinical high-frame-rate ultrasound imaging devices.
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The high economic value of Atlantic cod makes it prone to fraudulent activities in the market, thus achieving rapid and non-destructive identification of its authenticity has practical significance. This study investigated the hyperspectral imaging (HSI) systems with a Vis-NIR (400 - 1000 nm) and SWIR (900 - 1700 nm) spectral range, for determining the authenticity of Atlantic cod fillets in two frozen and thawed sample states. Results found that the model effect of Vis-NIR data was generally better than SWIR data. Random forest (RF) and Linear discriminant analysis (LDA) models of Vis-NIR data achieved 100 % accuracy. Variable screening algorithms of Successive projections algorithm (SPA) and Variable combination population analysis- iteratively retaining informative variables (VCPA-IRIV) maintained 100 % accuracy of the LDA model at VIS-NIR wavebands while simplifying the data operation burden. Overall, this study suggests that HSI is a promising solution for rapid and non-destructive detection of Atlantic cod authenticity.
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This study evaluates the survival outcomes of segmental ureterectomy (SU) combined with chemotherapy in patients with high-grade non-metastatic ureteral cancer (UC) using data from the SEER database. A total of 1757 patients with Grade III-IV non-metastatic UC were analyzed. Overall survival (OS) was assessed through Kaplan-Meier analysis, and independent prognostic factors were identified via Cox regression. A Nomogram model was developed and evaluated using the concordance index, area under the time-dependent ROC curve, calibration curves, and decision curve analysis. The 1-, 3-, and 5-year OS rates were 82.8%, 55.6%, and 42.8%, respectively. Age, treatment protocol, T stage, and N stage were significant prognostic factors. Both SU + chemotherapy and radical nephroureterectomy (RNU) + chemotherapy demonstrated comparable survival outcomes, outperforming surgery alone, particularly in patients aged 70 and older. The Nomogram demonstrated high predictive accuracy and clinical utility. These findings suggest that SU + chemotherapy offers survival benefits similar to RNU + chemotherapy, making it a viable option, especially for elderly patients or those with impaired renal function.
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Nomogramas , Programa de VERF , Neoplasias Ureterales , Humanos , Femenino , Masculino , Anciano , Neoplasias Ureterales/cirugía , Neoplasias Ureterales/tratamiento farmacológico , Neoplasias Ureterales/patología , Neoplasias Ureterales/mortalidad , Persona de Mediana Edad , Pronóstico , Clasificación del Tumor , Adulto , Terapia Combinada , Estimación de Kaplan-Meier , Uréter/cirugía , Uréter/patología , Nefroureterectomía/métodos , Anciano de 80 o más Años , Estadificación de Neoplasias , Resultado del TratamientoRESUMEN
An efficient and metal-free approach for the divergent synthesis of 2-fluoro-3-aryl-4H-benzo[4,5]imidazo[2,1-b][1,3]thiazines and α-trifluoromethyl-ß-arylthio tertiary alcohols from 2-mercaptoimidazoles and α-CF3 alkenes has been developed. The chemoselectivity was well controlled by base or light; a series of 2-fluoro-3-aryl-4H-benzo[4,5]imidazo[2,1-b][1,3]thiazines were afforded via base-mediated sequential SN2'- and SNV-type reactions. Meanwhile, α-trifluoromethyl-ß-arylthio tertiary alcohols could be selectively achieved through visible-light-driven and electron donor-acceptor (EDA) complex-initiated radical cascade thiolation/hydroxylation in the absence of base, transition metal, and external photocatalyst.
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Selenium (Se) deficiency induces an inflammatory response in the lungs, but the underlying mechanisms are unknown. Selenoprotein O (SelO) is the largest selenoprotein in terms of molecular weight, yet its potential biological functions have yet to be characterized. Our study revealed that Se deficiency leads to an imbalance in the expression of pro-inflammatory "M1" macrophages and anti-inflammatory "M2" macrophages in alveolar macrophages (AMs) and interstitial macrophages (IMs) and contributed to the development of lung inflammation. Through the analysis of differentially expressed selenoproteins, we identified SelO as a potential regulator of the imbalance in pulmonary macrophage polarization caused by Se deficiency. In vitro experiments showed that SelO knockdown enhanced the polarization of M1 macrophages while suppressing that of M2 macrophages. In addition, SelO knockdown reprogrammed macrophage metabolism to glycolysis, disrupting oxidative phosphorylation (OXPHOS). Mechanistically, SelO primarily targets mitochondrial transcription factor A (TFAM), which plays a crucial role in the transcription and replication of mitochondrial DNA (mtDNA) and is essential for mitochondrial biogenesis and energy metabolism. The deficiency of SelO affects TFAM, resulting in its uncontrolled degradation, which compromises mitochondrial function and energy metabolism. In summary, the findings presented here offer significant theoretical insights into the physiological functions of SelO.
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Microbubble-induced oxidation offers an effective approach for activating the C(sp3)-H bond of methane under mild conditions, achieving a methane activation rate of up to 6.7% per hour under optimized parameters. In this study, microbubbles provided an extensive gas-liquid interface that promoted the formation of hydroxyl (OHË) and hydrogen radicals (HË), which facilitated the activation of methane, leading to the generation of methyl radicals (CH3Ë). These species further participated in free-radical reactions at the interface, resulting in the production of ethane and formic acid. The microbubble system was optimized by adjusting gas-liquid interaction time, water temperature, and bubble size, with the optimal conditions (150 s of water-gas interaction, 15 °C, 50 µm bubble size) yielding a methane conversion rate of 171.5 ppm h-1, an ethane production rate of 23.5 ppm h-1, and a formic acid production rate of 2.3 nM h-1 during 8 h of continuous operation. The stability and efficiency of this process, confirmed through electron spin resonance, high-resolution mass spectrometry, and gas chromatography, suggest that microbubble-based methane activation offers a scalable and energy-efficient pathway for methane utilization.
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Objective: To evaluate the diagnostic utility of fat (hydroxyapatite) density [DFat (HAP)] on dual-energy computed tomography (DECT) for identifying clinical diagnosed multiple myeloma without bone disease (MNBD) that is not visible on conventional CT scans. Material and Methods: In this age-gender-examination sites matched case control prospective study, Chest and/or abdominal images on Revolution CT of MNBDs and control subjects were consecutive enrolled in a 1:2 ratio from October 2022 to November 2023. Multiple myeloma was clinical diagnosed according to criteria of the International Myeloma Working Group. Regions of interest (ROIs) were drawn separately for all thoracolumbar vertebrae in the scanning range by two radiologists. Additionally, a radiologist specializing in musculoskeletal imaging supervised the process. DFat (HAP) was extracted from each ROI. The spine was divided into upper thoracic (UPT), middle and lower thoracic (MLT), thoracolumbar (TL), and middle and lower lumbar (MLL) vertebrae. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the diagnostic performance of DFat (HAP) in diagnosing multiple myeloma, and the sensitivity, specificity, and accuracy under the optimal cut-off were determined by Youden index (sensitivity + specificity -1). Results: A total of 32 and MNBD patients and 64 control patients were included. The total number of ROIs outlined included MNBD group (n = 493) and control group (n = 986). For all vertebrae, DFat(HAP) got average performance in the diagnosis of MNBD (AUC = 0.733, p < 0.001) with a cut-off value of 958 (mg/cm3); the sensitivity, specificity, and accuracy were 58.8 %, 77.8 %, and 71.7 %, respectively. Regarding segment analysis, the diagnostic performance was good for all (AUC, 0.803-0.837; p < 0.001) but the UPT segment (AUC = 0.692, p = 0.002). The optimal diagnostic cut-off values for the MLT, TL, and MLL vertebrae were 955 mg/cm3, 947 mg/cm3, and 947 mg/cm3, respectively; the sensitivity, specificity, and accuracy were 80.0 %-87.5 %, 71.9 %-82.6 %, and 77.1 %-81.6 %, respectively. Conclusion: DECT was effective for detecting MNBD, and better diagnostic results can be obtained by grouping different spine segments.
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Herein, covalent triazine frameworks in eclipsed AA and staggered AB stacking modes are respectively used for the in-situ growth of TiO2, and two heterostructures are obtained. Due to the highly organized stacking of the molecular layer in CTF-AA that strengthens the interlayer interaction, the light absorption and carrier migration of CTF-AA/TiO2 are both enhanced in comparison to those of its component or CTF-AB/TiO2. Correspondently, the photocatalytic CO2 reduction reaction (CO2RR) of CTF-AA/TiO2 proffers 9.19 µmol·g-1·h-1 CH4 and 2.32 µmol·g-1·h-1 CO production, about 9.2 and 4.3 times greater than that of pristine TiO2, respectively. Even though the innate photoresponse of the triazine unit endows CTF-AB/TiO2 with augmented light capturing, its photocatalytic CO2 conversion is relatively insignificant. According to the analyses of the planar-averaged electron density difference and Bader charge, the unproductive CO2 efficiency might be due to the insufficient interfacial electron transfer from TiO2 to CTF-AB. Given that the ΔG (-3.22 eV) of CHO intermediate generation is lower than that of CO desorption (-1.23 eV), the reaction tends to further generate CH4 other than yielding CO. This study could shed fresh light over the reasonable design of effective photocatalytic heterostructures.
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Circulating neutral glycosphingolipids (neutral GSLs (nGSLs)) are a unique subset of nGSLs that detach from organs or cell membranes and enter the bloodstream. Altered molecular distribution of circulating nGSL is increasingly associated with diseases. However, profiling of circulating nGSLs presents a lasting challenge due to their low abundances and structural complexity. Although TiO2 magnetic nanoparticles (TiO2 MNPs) were effective for the enrichment of nGSLs in brain tissue, the protocol showed limited selectivity for circulating nGSLs because their abundances were 100-times lower in human plasma than in brain tissue. In this work, we optimized the key parameters of selective enrichment by TiO2 MNPs and achieved 1:10,000 selectivity for nGSLs over interfering phospholipids, while maintaining â¼70% recovery for different subclasses of nGSLs. By integrating TiO2 MNP-based selective enrichment with reversed-phase liquid chromatography mass spectrometry and charge-tagging Paternò-Büchi derivatization, we achieved deep profiling of over 300 structures of nGSLs and sulfatides across 5 orders of magnitude in relative abundances, a significant leap regarding lipid coverage. We also depicted the structural atlas of nGSLs with defined headgroup, long-chain base, N-acyl chain, the location of desaturation, and 2-hydroxylation. Such information provides a valuable resource for lipidomic studies concerning the roles of circulating nGSLs in health and diseases.
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Glicoesfingolípidos , Nanopartículas de Magnetita , Titanio , Titanio/química , Humanos , Nanopartículas de Magnetita/química , Glicoesfingolípidos/química , Animales , Cromatografía de Fase InversaRESUMEN
Electrification of water in clouds leads to fascinating redox reactions on Earth. However, little is known about cloud electrochemistry, except for lightning, a natural hazard that is nearly impossible to harness. We report a controllable electrochemistry that can be enabled in microclouds by fast phase switching of water between the microdroplet, vapor, and bulk phase. Due to the size-dependent charge transfer between droplets during atomization, this process generates an alternating voltage arising from the self-electrification and discharging of microdroplets, vapor, and bulk phase by electron and ion transfer. We show that the microclouds with alternating voltage cause 1,2-dichloroethane (ClH2C-CH2Cl) to be converted to vinyl chloride (H2CâCHCl) at â¼80% selectivity. These findings highlight the importance of controlled cloud electrochemistry in accelerating the removal of volatile organic compounds and treating contaminated water. We suggest that this work opens an avenue for harnessing cloud electrochemistry to solve challenging chemoselectivity problems in aqueous reactions of environmental and industrial importance.
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Mapping disulfide linkages is crucial for characterizing pharmaceutical proteins during drug development and quality control. Traditional bottom-up protein analysis workflows often suffer from incomplete mapping for tryptic peptides consisting of multiple disulfide bonds. Although the employment of a partial reduction of disulfide bonds can improve disulfide mapping, it becomes a bottleneck of analysis because individual tuning is often needed. Herein, we have developed an online disulfide-ene reaction system in which the composition of the reaction solvent can be programmed to achieve optimal partial reduction of tryptic disulfide peptides after liquid chromatography separation. By coupling this system onto a bottom-up protein analysis workflow, high coverage for sequencing (71-83%) and disulfide mapping (84-100%) was achieved for standard proteins consisting of 4-19 disulfide bonds. The analytical capability was further demonstrated by mapping 13 scrambled disulfide bonds in lysozyme and achieving compositional analysis of IgG isotypes (κ and λ) and subclasses (IgG1-IgG4) from human plasma.
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Disulfuros , Muramidasa , Disulfuros/química , Humanos , Muramidasa/química , Muramidasa/metabolismo , Inmunoglobulina G/química , Flujo de Trabajo , Proteínas/químicaRESUMEN
BACKGROUND: No significant difference in disease-specific survival and recurrence-free survival exists between papillary thyroid cancer (PTC) patients with high-risk features subjected to lobectomy and thyroidectomy. However, it is unclear which type of patients with unilateral PTC combined with ipsilateral clinical involved lymph nodes (cN1) can receive a less aggressive treatment. METHODS: We collected the medical records of 631 patients diagnosed with unilateral PTC and ipsilateral cN1. These patients initially underwent total thyroidectomy and bilateral central lymph node dissection (LND), with or without lateral LND. We conducted an analysis to investigate the associations between contralateral occult central lymph node metastasis (CLNM) and clinicopathologic factors. RESULTS: The proportion of contralateral occult CLNM was 38.9 %. Age ≤45 years, tumor diameter >1 cm, obesity, and involvement of lymph node regions ≥2 were independent risk factors for contralateral occult CLNM. Multifocality and ipsilateral neck high-volume lymph node metastases were independent risk factors among the postoperative pathological factors. A predicting model was developed to quantify the risk of each factor, which revealed that patients without any of the risk factors mentioned above had a 20-30 % probability of contralateral occult CLNM, whereas the probability was greater than 60 % when all factors were present. CONCLUSION: Based on the predictive nomograms, we proposed a risk stratification scheme based on different nomogram scores. In the debate about prophylactic central LND among contralateral central lymph node in unilateral PTC with ipsilateral clinical LNM, our nomograms provide the balance to avoid overtreatment and undertreatment through personal risk assessment.
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In this Letter, we propose a full-duplex dynamic time division multiple access (FDD-TDMA) scheme for multi-user underwater wireless optical communication (UWOC). It supports full-duplex communication through wavelength division duplex (WDD) and enhances the system throughput using dynamic time resource allocation. Additionally, a clock synchronization and compensation method is proposed for precise clock synchronization without time-keeping. With the proposed FDD-TDMA scheme and the clock synchronization and compensation method, we establish a two-user UWOC system based on on-off keying (OOK) modulation. Experiments are conducted in a 10â m water pool environment. The experimental results show that the designed system can achieve a data rate of 25â Mbps without error codes and 40â Mbps with a bit error rate (BER) below the forward error correction (FEC) limit. The FDD-TDMA scheme notably improves the system throughput when communication demands among users are variable compared to the conventional time division multiple access (TDMA). Moreover, a reduction in phase deviations from microseconds to ten nanoseconds is achieved by the clock synchronization and compensation method.
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BACKGROUND: In addition to their established action of synthetic lethality in tumor cells, poly(ADP-ribose) polymerase inhibitors (PARPis) also orchestrate tumor immune microenvironment (TIME) that contributes to suppressing tumor growth. However, it remains not fully understood whether and how PARPis trigger tumor-targeting immune responses. METHODS: To decode the immune responses reshaped by PARPis, we conducted T-cell receptor (TCR) sequencing and immunohistochemical (IHC) analyses of paired clinical specimens before and after niraparib monotherapy obtained from a prospective study, as well as ID8 mouse ovarian tumors. To validate the induction of immunogenic cell death (ICD) by PARPis, we performed immunofluorescence/IHC staining with homologous recombination deficiency tumor cells and patient-derived xenograft tumor tissues, respectively. To substantiate that PARPis elicited tumor cell pyroptosis, we undertook comprehensive assessments of the cellular morphological features, cleavage of gasdermin (GSDM) proteins, and activation of TNF-caspase signaling pathways through genetic downregulation/depletion and selective inhibition. We also evaluated the critical role of pyroptosis in tumor suppression and immune activation following niraparib treatment using a syngeneic mouse model with implanting CRISPR/Cas9 edited Gsdme-/ - ID8 tumor cells into C57BL/6 mice. RESULTS: Our findings revealed that PARPis augmented the proportion of neoantigen-recognized TCR clones and TCR clonal expansion, and induced an inflamed TIME characterized by increased infiltration of both innate and adaptive immune cells. This PARPis-strengthened immune response was associated with the induction of ICD, specifically identified as pyroptosis, which possessed distinctive morphological features and GSDMD/E cleavage. It was validated that the cleavage of GSDMD/E was due to elevated caspase 8 activity downstream of the TNFR1, rather than FAS and TRAIL-R. On PARP inhibition, the NF-κB signaling pathway was activated, leading to increased secretion of TNF-α and subsequent initiation of the TNFR1-caspase 8 cascade. Impeding pyroptosis through the depletion of Gsdme significantly compromised the tumor-suppressing effects of PARP inhibition and undermined the anti-immune response in the syngeneic ID8 mouse model. CONCLUSIONS: PARPis induce a specific type of ICD called pyroptosis via TNF-caspase 8-GSDMD/E axis, resulting in an inflamed TIME and augmentation of tumor-targeting immune responses. These findings deepen our understanding of PARPis activities and point toward a promising avenue for synergizing PARPis with immunotherapeutic interventions. TRIAL REGISTRATION NUMBER: NCT04507841.
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Neoplasias Ováricas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Piroptosis , Animales , Femenino , Humanos , Ratones , Línea Celular Tumoral , Gasderminas , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Proteínas de Unión a Fosfato/metabolismo , Piperidinas/farmacología , Piperidinas/uso terapéutico , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Piroptosis/efectos de los fármacos , Transducción de Señal , Microambiente Tumoral , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Objective: This study explores the possible connection between periodontitis and gut microbiota in East Asians, a relationship that has been largely unexplored until now. Methods: Using publicly available genome-wide association study (GWAS) data, we performed Mendelian randomization (MR). We analyzed GWAS summary statistics to assess if gut microbiota could causally influence periodontitis risk. We applied methods such as MR-Egger, weighted median, inverse variance weighting, and simple MR, and conducted sensitivity analyses to confirm our findings. Results: Utilizing the Inverse-Variance Weighted approach, we identified potential causal relationships between 17 host-genetically influenced gut microbiota characteristics and periodontitis, including Granulicatella adiacens, Bilophila wadsworthia, and Thermosinus. Specifically, G. adiacens was linked to an increased risk of periodontitis (odds ratios [OR] 1.07, 95% confidence interval [CI] 1.02-1.15, p = 0.0004), while B. wadsworthia was linked to a decreased likelihood of tooth loss (OR 0.98, 95% CI 0.96-0.99, p = 0.0005). No evidence of pleiotropy or heterogeneity was observed across sensitivity analyses. Conclusion: This study reveals a causal relationship between specific microorganisms and periodontitis in the Asian population, shedding light on the influence of gut microbiota on periodontitis.
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Achieving high-efficiency perovskite solar cells (PSCs) hinges on the precise control of the perovskite film crystallization process, often improved by the inclusion of additives. While dimethyl sulfoxide (DMSO) is traditionally used to manage this process, its removal from the films is problematic. In this work, methyl phenyl sulfoxide (MPSO) was employed instead of DMSO to slow the crystallization rate, as MPSO is more easily removed from the perovskite structure. The electron delocalization associated with the benzene ring in MPSO decreases the electron density around the oxygen atom in the sulfoxide group, thus reducing its interaction with PbI2. This strategy not only sustains the formation of a crystallization-slowing intermediate phase but also simplifies the elimination of the additive. Consequently, the optimized PSCs achieved a leading power conversion efficiency (PCE) of 25.95% along with exceptional stability. This strategy provides a novel method for fine-tuning perovskite crystallization to enhance the overall performance of photovoltaic devices.
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The hospital indoor environment has a crucial impact on the microbial exposures that humans encounter. Resistance to antibiotics is a mechanism used by bacteria to develop resilience in indoor environments, and the widespread use of antibiotics has led to changes in the ecological function of resistance genes and their acquisition by pathogens. By integrating the 16S rRNA Illumina sequencing and high-throughput-quantitative PCR approaches with water and air dust samples across seven departments in Peking University Shenzhen Hospital, China, this study yields intriguing findings regarding the department-specific variations, correlations and source tracing of bacteria, antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) within the hospital indoor environment. A notable observation was the pivotal role played by seasonal variations in shaping the bacterial composition across the entire hospital indoor environment. Another department-specific finding was the correlation between ARGs and MGEs abundance, which was evident in the overall hospital indoor environment, but not found in the blood test room, ophthalmology, and gynecology departments. Notably, as an important source of bacteria and ARGs/MGEs for the blood test room, the gynecology department also presented a close link between bacterial communities and the presence of ARGs/MGEs. Additionally, the results reiterate the importance of surveillance and monitoring of antibiotic resistance, specifically in Legionella spp. in man-made water systems, and highlight the significance of understanding genetic elements like Tp614 involved in gene transfer and recombination, and their impact on antimicrobial treatment efficacy. KEY POINTS: ⢠The department-specific variations, correlations and source tracing of bacteria, ARGs, and MGEs were uncovered in the hospital's indoor environment. ⢠Although each department exhibited consistent seasonal impacts on bacterial compositions, the co-occurrence between the presence of ARGs and MGEs was exclusively evident in the emergency, surgery, pneumology and otolaryngology departments. ⢠The gynecology department emerged as a crucial source of bacteria, ARGs and MGEs within the hospital. Additionally, it was found to exhibit a significant correlation between bacterial communities and the presence of ARGs and MGEs.
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Microbiología del Aire , Bacterias , ARN Ribosómico 16S , Bacterias/genética , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , ARN Ribosómico 16S/genética , China , Humanos , Hospitales , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Polvo/análisis , Secuencias Repetitivas Esparcidas/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Contaminación del Aire Interior/análisis , Estaciones del Año , Genes BacterianosRESUMEN
Atmospheric oxidation processes are of central importance in atmospheric climate models. It is often considered that volatile organic molecules are mainly removed by hydroxyl radical; however, the kinetics of some reactions of hydroxyl radical with volatile organic molecules are slow. Here we report rate constants for rapid reactions of formyl fluoride with Criegee intermediates. These rate constants are calculated by dual-level multistructural canonical variational transition state theory with small-curvature tunneling (DL-MS-CVT/SCT). The treatment contains beyond-CCSD(T) electronic structure calculations for transition state theory, and it employs validated density functional input for multistructural canonical variational transition state theory with small-curvature tunneling and for variable-reaction-coordinate variational transition state theory. We find that the M11-L density functional has higher accuracy than CCSD(T)/CBS for the HC(O)F + CH2OO and HC(O)F + anti-CH3CHOO reactions. We find significant negative temperature dependence in the ratios of the rate constants for HC(O)F + CH2OO/anti-CH3CHOO to the rate constant for HC(O)F + OH. We also find that different Criegee intermediates have different rate-determining-steps in their reactions with formyl fluoride, and we find that the dominant gas-phase removal mechanism for HC(O)F in the atmosphere is the reaction with CH2OO and/or anti-CH3CHOO Criegee intermediates.