Quantifying Methane Influx from Sewer into Wastewater Treatment Processes.

Wastewater treatment contributes substantially to methane (CH4) emissions, yet monitoring and tracing face challenges because the treatment processes are often treated as a "black box". Particularly, despite growing interest, the amount of CH4 carryover and influx from the sewer and its impacts on overall emissions remain unclear. This study quantified CH4 emissions from six wastewater treatment plants (WWTPs) across China, utilizing existing multizonal odor control systems, with a focus on Beijing and Guiyang WWTPs. In the Beijing WWTP, almost 90% of CH4 emissions from the wastewater treatment process were conveyed through sewer pipes, affecting emissions even in the aerobic zone of biological treatment. In the Guiyang WWTP, where most CH4 from the sewer was released at the inlet well, a 24 h online monitoring revealed CH4 fluctuations linked to neighborhood water consumption and a strong correlation to influent COD inputs. CH4 emission factors monitored in six WWTPs range from 1.5 to 13.4 gCH4/kgCODrem, higher than those observed in previous studies using A2O technology. This underscores the importance of considering CH4 influx from sewer systems to avoid underestimation. The odor control system in WWTPs demonstrates its potential as a cost-effective approach for tracing, monitoring, and mitigating CH4.

Microalgae cultivation using ammonia and carbon dioxide concentrations typical of pig barns.

While global population growth drives increased production efficiency in animal agriculture, there is a growing demand for environmentally friendly practices, particularly in reducing air pollutant emissions from concentrated animal feeding operations. This study explores the potential of cultivating microalgae in photobioreactors (PBRs) as an eco-friendly and cost-effective approach to mitigate NH3 and CO2 emissions from pig barns. Unlike traditional physicochemical mitigation systems, microalgae offer a renewable solution by converting pollutants into valuable biomass. The research focused on Scenedesmus dimorphus growth under typical NH3 and CO2 concentrations found in the indoor air of pig barns. Four NH3 (0, 12, 25, and 50 ppm) and four CO2 concentrations (350, 1200, 2350, and 3500 ppm) were tested using photobioreactors. Results showed a maximum specific growth rate of 0.83 d-1 with 12 ppm NH3 and 3500 ppm CO2. The dry biomass concentration was significantly higher (1.16 ± 0.08 g L-1; p < 0.01) at 25 ppm NH3 and 2350 ppm CO2 than other test conditions. S. dimorphus demonstrated the peak NH3 and CO2 fixation rates (23.8 ± 2.26 mg NH3 L-1 d-1 and 432.24 ± 41.09 mg CO2 L-1 d-1) at 25 ppm NH3 and 2350 ppm CO2. These findings support the feasibility of using algae to effectively remove air pollutants in pig barns, thereby improving indoor air quality.

Microplastics and associated chemicals in drinking water: A review of their occurrence and human health implications.

Microplastics (MPs) have entered drinking water (DW) via various pathways, raising concerns about their potential health impacts. This study provides a comprehensive review of MP-associated chemicals, such as oligomers, plasticizers, stabilizers, and ultraviolet (UV) filters that can be leached out during DW treatment and distribution. The leaching of these chemicals is influenced by various environmental and operating factors, with three major ones identified: MP concentration and polymer type, pH, and contact time. The leaching process is substantially enhanced during the disinfection step of DW treatment, due to ultraviolet light and/or disinfectant-triggered reactions. The study also reviewed human exposure to MPs and associated chemicals in DW, as well as their health impacts on the human nervous, digestive, reproductive, and hepatic systems, especially the neuroendocrine toxicity of endocrine-disrupting chemicals. An overview of MPs in DW, including tap water and bottled water, was also presented to enable a background understanding of MPs-associated chemicals. In short, certain chemicals leached from MPs in DW can have significant implications for human health and demand further research on their long-term health impacts, mitigation strategies, and interactions with other pollutants such as disinfection byproducts (DBPs) and per- and polyfluoroalkyl substances (PFASs). This study is anticipated to facilitate the research and management of MPs in DW and beverages.

Emerging electro-driven technologies for phosphorus enrichment and recovery from wastewater: A review.

The recovery of phosphorus from wastewater is a critical step in addressing the scarcity of phosphorus resources. Electro-driven technologies for phosphorus enrichment have gathered significant attention due to their inherent advantages, such as mild operating conditions, absence of secondary pollution, and potential integration with other technologies. This study presents a comprehensive review of recent advancements in the field of phosphorus enrichment, with a specific focus on capacitive deionization and electrodialysis technologies. It highlights the underlying principles and effectiveness of electro-driven techniques for phosphorus enrichment while systematically comparing energy consumption, enrichment rate, and concentration factor among different technologies. Furthermore, the study provides a thorough analysis of the capacity of various technologies to selectively enrich phosphorus and proposes several methods and strategies to enhance selectivity. These insights offer valuable guidance for advancing the future development of electrochemical techniques with enhanced efficiency and effectiveness in phosphorus enrichment from wastewater.

Extracellular electron transfer and the conductivity in microbial aggregates during biochemical wastewater treatment: A bottom-up analysis of existing knowledge.

Microbial extracellular electron transfer (EET) plays a crucial role in bioenergy production and resource recovery from wastewater. Interdisciplinary efforts have been made to unveil EET processes at various spatial scales, from nanowires to microbial aggregates. Electrical conductivity has been frequently measured as an indicator of EET efficiency. In this review, the conductivity of nanowires, biofilms, and granular sludge was summarized, and factors including subjects, measurement methods, and conducting conditions that affect the conductivity difference were discussed in detail. The high conductivity of nanowires does not necessarily result in efficient EET in microbial aggregates due to the existence of non-conductive substances and contact resistance. Improving the conductivity measurement of microbial aggregates is important because it enables the calculation of an EET flux from conductivity and a comparison of the flux with mass transfer coefficients. This review provides new insight into the significance, characterization, and optimization of EET in microbial aggregates during a wastewater treatment process.

Growth of Scenedesmus dimorphus in swine wastewater with versus without solid-liquid separation pretreatment.

Scenedesmus dimorphus was cultivated in raw and pretreated swine wastewater (SW) with 6-L photobioreactors (PBRs) to investigate the effect of solid-liquid separation on algal growth. The same aerated PBRs containing no algae were used as control. Moderate COD and nitrogen removal from the SW was achieved with the algal PBRs. However, compared to the control reactors, they offered no consistent treatment boost. Improved algal growth occurred in the pretreated SW, as measured by maximum algal cell count (3202 ± 275 × 106 versus 2286 ± 589 × 106 cells L-1) and cell size. The enhanced algal growth in the pretreated SW resulted in relatively high nitrogen (5.7 %) and organic matter contents in the solids harvested at the end of cultivation experiments, with ∼25.6 % of nitrogen in the SW retained in the solids and ∼9.1 % absorbed by algae. The pretreatment also resulted in elevated phosphorus removal. This study is anticipated to foster the development of microalgae-based SW treatment processes.

CCL17 acts as a novel therapeutic target in pathological cardiac hypertrophy and heart failure.

Circulating proteomic signatures of age are closely associated with aging and age-related diseases; however, the utility of changes in secreted proteins in identifying therapeutic targets for diseases remains unclear. Serum proteomic profiling of an age-stratified healthy population and further community-based cohort together with heart failure patients study demonstrated that circulating C-C motif chemokine ligand 17 (CCL17) level increased with age and correlated with cardiac dysfunction. Subsequent animal experiments further revealed that Ccll7-KO significantly repressed aging and angiotensin II (Ang II)-induced cardiac hypertrophy and fibrosis, accompanied by the plasticity and differentiation of T cell subsets. Furthermore, the therapeutic administration of an anti-CCL17 neutralizing antibody inhibited Ang II-induced pathological cardiac remodeling. Our findings reveal that chemokine CCL17 is identifiable as a novel therapeutic target in age-related and Ang II-induced pathological cardiac hypertrophy and heart failure.

Cultivation of Scenedesmus dimorphus with air contaminants from a pig confinement building.

The continual consolidation and concentration of animal feeding operations (AFOs) raises various environmental challenges, including air pollutant emission. Cost-effective mitigation technologies are pursued to protect the health and wellbeing of animals and farmers as well as the environment. Previous lab studies utilized ammonia (NH3) and carbon dioxide (CO2), two major air pollutants in AFOs, for microalgal cultivation. However, the field performance of this algae-based mitigation approach has yet to be investigated. In this study, two photobioreactors (PBRs) were tested in a nursery pig barn to mitigate NH3 and CO2 while growing Scenedesmus dimorphus (S. dimorphus). Pit air was fed into the PBRs where the two pollutants were adsorbed by S. dimorphus as nutrients to produce algal biomass and oxygen gas (O2). The cleaned air then recirculated back to the room space. S. dimorphus reached its maximum cell count on the 17th day of the experiment when NH3 and CO2 concentrations in the pit air were 25.6 ppm and 3150 ppm, respectively. The maximum biomass concentration occurred on the 11th day when the NH3 and CO2 concentrations were 14.6 and 2250 ppm, respectively. The average mitigation efficiency was 31-50% for NH3 and 1-1.7% for CO2. The costs for removing 1 g NH3 and CO2 were estimated to be $3.77 and $0.20, respectively. This study shows that an integrated PBR system is technically feasible for reducing pig barn air pollutant emission while producing microalgae as a valuable product.

Synthesis of Carbon Nanotubes (CNTs) from Poultry Litter for Removal of Chromium (Cr (VI)) from Wastewater.

Pakistan, an agricultural country, raises 146.5 million commercial and domestic poultry birds, which generate around 544,831 tons of waste per year. This waste finds its final disposal in agricultural land as soil fertilizer or disposal site amendment. The usage of poultry litter for this purpose is uncontrolled, which results in environmental degradation such as emission of greenhouse gases, e.g., methane. However, alternative options such as thermochemical conversion of poultry litter can offer better solutions where this waste can be used as a low-cost carbon source for the synthesis of Multiwalled Carbon Nanotubes (MWCNTs). In this study, efforts were made to utilize this cheap and plentiful carbon source for the synthesis of CNTs in the presence of Ni/Mo/MgO as a catalyst, through pyrolysis. For a better yield of carbon product, the optimum ratio for the catalysts (Ni/Mo/MgO) was found to be 4:0.2:1. Furthermore, the process parameters were also optimized for better carbon yield. A good yield of CNTs resulted from a pyrolysis time of 12 min, a temperature of 825 °C, and a catalyst weight of 100 mg. The structure and morphology of the produced nanotubes were confirmed through X-ray Diffractometer (X-RD) and Scanning Electron Microscopy (SEM). The environmental application of the nanotubes was tested in a synthetic chromium solution in the lab using a batch experiment. Different experimental conditions (pH, adsorbent dosage, and contact time) were optimized to improve the adsorption of Cr (VI) by carbon nanotubes and a UV-Visible spectrophotometer was used at 540 nm to measure the absorbance of Cr (VI). The results showed that up to 81.83% of Cr (VI) removal was achieved by using 8 mg of CNTs at pH 3 with 400 rpm at 180 min of contact time. Thus, it was concluded that poultry litter can be a useful source for the synthesis of MWCNTs and thereby removal of Cr (VI) from industrial tanneries' wastewater.

Establishing a Risk Prediction Model for Atherosclerosis in Systemic Lupus Erythematosus.

Background and aims: Patients with systemic lupus erythematosus (SLE) have a significantly higher incidence of atherosclerosis than the general population. Studies on atherosclerosis prediction models specific for SLE patients are very limited. This study aimed to build a risk prediction model for atherosclerosis in SLE. Methods: RNA sequencing was performed on 67 SLE patients. Subsequently, differential expression analysis was carried out on 19 pairs of age-matched SLE patients with (AT group) or without (Non-AT group) atherosclerosis using peripheral venous blood. We used logistic least absolute shrinkage and selection operator regression to select variables among differentially expressed (DE) genes and clinical features and utilized backward stepwise logistic regression to build an atherosclerosis risk prediction model with all 67 patients. The performance of the prediction model was evaluated by area under the curve (AUC), calibration curve, and decision curve analyses. Results: The 67 patients had a median age of 42.7 (Q1-Q3: 36.6-51.2) years, and 20 (29.9%) had atherosclerosis. A total of 106 DE genes were identified between the age-matched AT and Non-AT groups. Pathway analyses revealed that the AT group had upregulated atherosclerosis signaling, oxidative phosphorylation, and interleukin (IL)-17-related pathways but downregulated T cell and B cell receptor signaling. Keratin 10, age, and hyperlipidemia were selected as variables for the risk prediction model. The AUC and Hosmer-Lemeshow test p-value of the model were 0.922 and 0.666, respectively, suggesting a relatively high discrimination and calibration performance. The prediction model had a higher net benefit in the decision curve analysis than that when predicting with age or hyperlipidemia only. Conclusions: We built an atherosclerotic risk prediction model with one gene and two clinical factors. This model may greatly assist clinicians to identify SLE patients with atherosclerosis, especially asymptomatic atherosclerosis.

Development of a low-cost UAV-based system for CH4 monitoring over oil fields.

The recent booming of oil and gas production in the U.S. sparks a growing concern about greenhouse gas emissions from the petroleum industry. This study aimed to develop a low-cost UAV-based system for CH4 monitoring over oil fields. The system consisted of an airborne sensor node, a ground station, and a laptop. The sensor node was comprised of low-cost gas sensors, a microcontroller, a LoRa wireless transceiver, a GPS module, and an SD card reader. The ground station included a microcontroller and a LoRa transceiver. Both the sensor node and the ground station were programmed using Arduino. A graphic user interface was created using LabVIEW for data logging and visualization on the laptop. A preliminary test showed that the system was capable of measuring CH4 concentrations, along with temperature, humidity, and GPS location; while sending the real-time data to the ground station up to ∼1 km away without any loss. The system was further tested at two oil production sites in North Dakota. The results revealed a heterogeneous distribution of CH4 over the sites due to flares and road traffic, demonstrating a potential application of the system for air quality survey and gas leakage detection. The advantage of this system lies in its light weight (∼540 g), low cost (∼$300), expandability, ease of deployment and operation. Data quality collected by the system depended on the gas sensors chosen. With advancement in sensor technologies, it is expected that the quality of monitoring data can be considerably improved in the near future.

Myocardial Injury on Admission as a Risk in Critically Ill COVID-19 Patients: A Retrospective in-ICU Study.

OBJECTIVE: The aim of this study was to investigate the incidence, clinical presentation, cardiovascular (CV) complications, and mortality risk of myocardial injury on admission in critically ill intensive care unit (ICU) inpatients with COVID-19. DESIGN: A single-center, retrospective, observational study. SETTING: A newly built ICU in Tongji hospital (Sino-French new city campus), Huazhong University of Science and Technology, Wuhan, China. PARTICIPANTS: Seventy-seven critical COVID-19 patients. INTERVENTIONS: Patients were divided into a myocardial injury group and nonmyocardial injury group according to the on-admission levels of high-sensitivity cardiac troponin I. MEASUREMENTS AND MAIN RESULTS: Demographic data, clinical characteristics, laboratory tests, treatment, and clinical outcome were evaluated, stratified by the presence of myocardial injury on admission. Compared with nonmyocardial injury patients, patients with myocardial injury were older (68.4 ± 10.1 v 62.1 ± 13.5 years; p = 0.02), had higher prevalence of underlying CV disease (34.1% v 11.1%; p = 0.02), and in-ICU CV complications (41.5% v 13.9%; p = 0.008), higher Acute Physiology and Chronic Health Evaluation II scores (20.3 ± 7.3 v 14.4 ± 7.4; p = 0.001), and Sequential Organ Failure Assessment scores (7, interquartile range (IQR) 5-10 v 5, IQR 3-6; p < 0.001). Myocardial injury on admission increased the risk of 28-day mortality (hazard ratio [HR], 2.200; 95% confidence interval [CI] 1.29 to 3.74; p = 0.004). Age ≥75 years was another risk factor for mortality (HR, 2.882; 95% CI 1.51-5.50; p = 0.002). CONCLUSION: Critically ill patients with COVID-19 had a high risk of CV complications. Myocardial injury on admission may be a common comorbidity and is associated with severity and a high risk of mortality in this population.

Reduction in SLEDAI is associated with improved arterial stiffness in systemic lupus erythematosus.

Lipid abnormalities are an important cause of premature atherosclerosis in patients with systemic lupus erythematosus (SLE). This longitudinal study investigates the changes in lipid profile and arterial stiffness with SLE disease activity index (SLEDAI) reduction.Fifty one female SLE patients with baseline SLEDAI ≥ 6 and SLEDAI reduction >3 at 1-year follow-up were included. Neutrophil-to-lymphocyte ratio (NLR), erythrocyte sedimentation rate (ESR), high-sensitivity C-reactive protein (hsCRP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and mean brachial-ankle pulse wave velocity (baPWV) were measured and compared between baseline and 1-year follow-up. Correlations between inflammation biomarkers, SLEDAI, mean baPWV and lipid profile were assessed.We observed significant decreases in ESR, mean baPWV, TG and TC to HDL-C ratio compared with baseline at 1-year follow up, while HDL-C, hsCRP, and NLR were not significantly changed. Significant correlations were found between the reductions in ESR and TG, and SLEDAI and mean baPWV, with adjustment to age, disease duration, blood pressure, and medications (prednisone, immunosuppressants and ARB/ACEI).SLE patients experiencing SLEDAI reductions showed improvements in arterial stiffness. This finding may provide insight into the beneficial effects of reducing SLEDAI on atherosclerosis risk in SLE.

Long noncoding RNA ASB16-AS1 inhibits adrenocortical carcinoma cell growth by promoting ubiquitination of RNA-binding protein HuR.

Adrenocortical carcinoma is one of the aggressive malignancies and it originates from the cortex of adrenal gland. Dysregulation of long non-coding RNA plays important roles in the development of adrenocortical carcinoma. Here, we found that lncRNA ASB16-AS1 was down-regulated in adrenocortical carcinoma and ASB16-AS1 functions as tumor suppressor in vitro and in vivo. We then found that IGF1R and CDK6 are regulated by ASB16-AS1 in adrenocortical carcinoma cells by transcriptome RNA sequencing. ASB16-AS1 associates with RNA-binding protein HuR (ELAVL1) as revealed by RNA pull-down following mass spectrometry. Also, ASB16-AS1 inhibits HuR expression post-translationally by promoting its ubiquitination. ASB16-AS1 regulates IGF1R and CDK6 mRNA expression through RNA-binding protein HuR. We then found that inhibition of ASB16-AS1 attenuates the binding of ubiquitin E3 ligase BTRC to HuR and subsequently inhibits HuR protein unbiquitination and degradation. BTRC knock-down could reverse the effect of AB16-AS1 on HuR, CDK6, and IGF1R levels. Collectively, these results demonstrate that ASB16-AS1 regulates adrenocortical carcinoma cell proliferation and tackling the level of ASB16-AS1 may be developed to treat adrenocortical carcinoma.

Intracellular calcium current disorder and disease phenotype in OBSCN mutant iPSC-based cardiomyocytes in arrhythmogenic right ventricular cardiomyopathy.

Obscurin participates in the development of striated muscles and maintenance of the functional sarcoplasmic reticulum. However, the role of obscurin in arrhythmogenic right ventricular cardiomyopathy (ARVC) is not well understood. We aimed to study the novel obscurin mutations in the pathogenesis of ARVC and the underlying mechanisms. Methods: We generated induced pluripotent stem cells (iPSC) through retroviral reprogramming of peripheral blood mononuclear cells isolated from a 46-year-old female diagnosed with ARVC, carrying a mutation in OBSCN. The cells differentiated into functional iPSC-based cardiomyocytes (iPSC-CMs), whose phenotype was determined by transmission electron microscopy, electrophysiological description, immunofluorescence staining, and Oil Red O staining. Molecular characterization was performed by bioinformatic analyses, and identification by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Results: ARVC-iPSC-CMs mutation in OBSCN showed significant accumulation of lipids, increased pleomorphism, irregular Z-bands, and increased L type calcium currents. Functional enrichment analysis identified pathways involved in focal adhesion and structure formation; the adipocytokines and PPAR signaling pathways were also activated in the ARVC group. Moreover, our results from ultra-high-resolution microscopy, qRT-PCR and Western blotting confirmed that the mutant OBSCN protein and its anchor protein, Ank1.5, showed structural disorder and decreased expression, but there was increased expression of junctional protein N-Cadherin. Further analysis revealed the gene expression of other desmosomal proteins in ARVC-iPSC-CMs was also decreased but some adipogenesis pathway-related proteins (PPARγ, C/EBPα, and FABP4) were increased. Conclusion: A novel frameshift mutation in OBSCN caused phenotypic alteration accompanied by disrupted localization and decreased expression of its anchoring protein Ank1.5. Furthermore, there was an accumulation of lipids with an increase in fatty fibrosis area and myocardial structural disorder, possibly leading to dysrhythmia in calcium channel-related myocardial contraction. These observations suggested the possibility of attenuating ARVC progression by therapeutic modulation of OBSCN expression.

Risk factors for progression of carotid intima-media thickness in patients with systemic lupus erythematosus: protocol for an observational cohort study in China.

INTRODUCTION: Accelerated atherosclerosis is a major complication of systemic lupus erythematosus (SLE), and it leads to increased cardiovascular morbidity and mortality in patients with SLE. This study aimed to investigate the natural progression of carotid intima-media thickness (CIMT), and to examine the risk factors for progression of CIMT and atherosclerotic plaques based on a Chinese SLE cohort. METHODS AND ANALYSIS: Participants were continuously enrolled as outpatients of the Department of Rheumatology in Peking Union Medical College Hospital (PUMCH) from October 2013 to December 2016. Inclusion criteria were as follows: (1) age ≥18 years, (2) fulfilment of clinical classification criteria of SLE and (3) provision of signed written informed consent. Patients with clinically overt coronary artery disease, a history of cardiovascular disease (previous stroke, heart failure, myocardial infarction, angina or symptomatic peripheral artery disease) and malignancy, and pregnant/lactating women were excluded. The primary outcome is progression of CIMT from baseline. A total of 440 patients with SLE will be enrolled. Participants will receive follow-up surveys ~5 years after their baseline visit. A standard structural survey form, including demographic data, medical history, clinical and laboratory assessments and CIMT measurement, is planned for data collection at baseline and follow-up. The risk prediction model for progression of CIMT will be created by using a mixed effect model. ETHICS AND DISSEMINATION: The study protocol was approved by the institutional review board of PUMCH (S-599). Informed consent was obtained from all participants according to the Declaration of Helsinki on Biomedical Research Involving Human Studies. All data will be managed confidentially according to guidelines and legislation. Dissemination will include publication of scientific papers and/or presentations of the study findings at international conferences.

Identification and validation of four hub genes involved in the plaque deterioration of atherosclerosis.

In recent years, intense research has been conducted to explore the diagnostic value of mRNA expression differences in atherosclerosis (AS). Nevertheless, because various technology platforms are applied and sample sizes are small, the results are inconsistent among the studies. We conducted a comprehensive analysis of a total of 161 tissue samples from 4 published studies after evaluating 230 datasets from the Gene Expression Omnibus and ArrayExpress. Adopting the newly published robust rank aggregation approach, combined with Kyoto Encyclopedia of Genes and Genomes pathway analysis, Gene Ontology functional enrichment analysis, and protein-protein interaction network construction, we identified four significantly upregulated genes (CCL4, CCL18, MMP9 and SPP1) for diagnosing AS, even in the advanced stage. Then, we performed gene set enrichment analysis to identify the pathways that were most affected by altered mRNA expression in atherosclerotic plaques. We found that four hub genes cooperatively targeted lipid metabolism and inflammatory immune-related pathways and validated their high expression levels in ruptured plaques by qRT-PCR, western blot analysis and immunohistochemical staining. In summary, our study showed that these genes can be used as interventional targets for plaque progression, and the results suggested we should focus on small changes in these key indicators in the clinical setting.

DL-cysteine and L-cystine formation and their enhancement effects during sulfur autotrophic denitrification.

Sulfur autotrophic denitrification has been proved feasible for nitrate removal from aquatic environments and it utilizes elemental sulfur as the electron donor. A maximum denitrification rate of 194.57 mg N/L·d was achieved with biogenic sulfur as electron donor in a mixed culture collected from sulfur packed bed reactors; this rate was considerably higher than that delivered by α-S8 or µ-S in the same mixed culture. The elemental sulfur was also tested in the pure culture of Thiobacillus denitrificans, while a lower denitrification rate was noted than in the mixed culture, bio-S (4.86 mg N/L·d) again outperformed other two elemental sulfur's. X-ray absorption near edge structure spectra were collected to examine possible metabolic intermediates during the sulfur autotrophic denitrification process. The analysis revealed the existence of two major intermediates: DL-cysteine and L-cystine. They were found to not only provide electrons but also play a critical role in promoting the elemental sulfur-mediated sulfur autotrophic denitrification process. In general, we investigated the formation and enhancement effects of sulfur intermediates in the sulfur autotrophic denitrification process.

Effect of metformin on all-cause and cardiovascular mortality in patients with coronary artery diseases: a systematic review and an updated meta-analysis.

BACKGROUND: Metformin is the most widely prescribed drug to lower glucose and has a definitive effect on the cardiovascular system. The goal of this systematic review and meta-analysis is to assess the effects of metformin on mortality and cardiac function among patients with coronary artery disease (CAD). METHODS: Relevant studies reported before October 2018 was retrieved from databases including PubMed, EMBASE, Cochrane Library and Web of Science. Hazard ratio (HR) was calculated to evaluate the all-cause mortality, cardiovascular mortality and incidence of cardiovascular events (CV events), to figure out the level of left ventricular ejection fraction (LVEF), creatine kinase MB (CK-MB), type B natriuretic peptide (BNP) and to compare the average level of low density lipoprotein (LDL). RESULTS: In this meta-analysis were included 40 studies comprising 1,066,408 patients. The cardiovascular mortality, all-cause mortality and incidence of CV events were lowered to adjusted HR (aHR) = 0.81, aHR = 0.67 and aHR = 0. 83 respectively after the patients with CAD were given metformin. Subgroup analysis showed that metformin reduced all-cause mortality in myocardial infarction (MI) (aHR = 0.79) and heart failure (HF) patients (aHR = 0.84), the incidence of CV events in HF (aHR = 0.83) and type II diabetes mellitus (T2DM) patients (aHR = 0.83), but had no significant effect on MI (aHR = 0.87) and non-T2DM patients (aHR = 0.92). Metformin is superior to sulphonylurea (aHR = 0.81) in effects on lowering the incidence of CV events and in effects on patients who don't use medication. The CK-MB level in the metformin group was lower than that in the control group standard mean difference (SMD) = - 0.11). There was no significant evidence that metformin altered LVEF (MD = 2.91), BNP (MD = - 0.02) and LDL (MD = - 0.08). CONCLUSION: Metformin reduces cardiovascular mortality, all-cause mortality and CV events in CAD patients. For MI patients and CAD patients without T2DM, metformin has no significant effect of reducing the incidence of CV events. Metformin has a better effect of reducing the incidence of CV events than sulfonylureas.

Feasibility of coupling a thermal/optical carbon analyzer to a quadrupole mass spectrometer for enhanced PM2.5 speciation.

A thermal/optical carbon analyzer (TOA), normally used for quantification of organic carbon (OC) and elemental carbon (EC) in PM2.5 (fine particulate matter) speciation networks, was adapted to direct thermally evolved gases to an electron impact quadrupole mass spectrometer (QMS), creating a TOA-QMS. This approach produces spectra similar to those obtained by the Aerodyne aerosol mass spectrometer (AMS), but the ratios of the mass to charge (m/z) signals differ and must be remeasured using laboratory-generated standards. Linear relationships are found between TOA-QMS signals and ammonium (NH4+), nitrate (NO3-), and sulfate (SO42-) standards. For ambient samples, however, positive deviations are found for SO42-, compensated by negative deviations for NO3-, at higher concentrations. This indicates the utility of mixed-compound standards for calibration or separate calibration curves for low and high ion concentrations. The sum of the QMS signals across all m/z after removal of the NH4+, NO3-, and SO42- signals was highly correlated with the carbon content of oxalic acid (C2H2O4) standards. For ambient samples, the OC derived from the TOA-QMS method was the same as the OC derived from the standard IMPROVE_A TOA method. This method has the potential to reduce complexity and costs for speciation networks, especially for highly polluted urban areas such as those in Asia and Africa. IMPLICATIONS: Ammonium, nitrate, and sulfate can be quantified by the same thermal evolution analysis applied to organic and elemental carbon. This holds the potential to replace multiple parallel filter samples and separate laboratory analyses with a single filter and a single analysis to account for a large portion of the PM2.5 mass concentration.