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1.
BMC Cancer ; 24(1): 1063, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198814

RESUMO

BACKGROUND: Pancreatic cancer is one of the deadliest cancers in the world. In recent years, the incidence and mortality rates of pancreatic cancer have shown an increasing trend year by year. This study investigates the independent effects of age, period, and cohort on the global incidence, mortality, and disability-adjusted life years (DALYs) of pancreatic cancer from 1990 to 2019, and evaluates the differences in the burden of pancreatic cancer across regions with different Sociodemographic Index (SDI) levels. METHODS: Estimating the impact of age, period, and cohort on pancreatic cancer disease burden in different SDI regions using age-period-cohort modeling with data (with 95% uncertainty intervals [UI]) from the Global Burden of Disease (GBD) Study 2019 and net drift of age-standardized incidence rates (ASIR), age-standardized mortality rates (ASMR), and age-standardized DALY rates (ASDR) for pancreatic cancer in 120 countries. RESULTS: The number of new cases of pancreatic cancer worldwide increased from 197,348 (95% UI: 188,604,203,971) in 1990 to 530,297 (486,175,573,635) in 2019, the number of deaths increased from 198,051 (189,329 to 204,763) in 1990 to 531,107 (491,948 to 566,537) in 2019, and the number of DALY increased from 4,647,207 (4,465,440 to 4,812,129) in 1990 to 11,549,016 (10,777,405 to 1,238,912) in 2019. The ASIR of the average levels in global pancreatic cancer increased from 5.22 (4.97 to 5.40) per 100,000 population to 6.57 (6.00 to 7.09) per 100,000 population, the ASMR increased from 5.34 (5.07 to 5.52) per 100,000 population to 6.62 (6.11 to 7.06) per 100,000 population, and the ASDR increased from 115.47 (110.82 to 119.60) per 100,000 population to 139.61 (130.18 to 149.14) per 100,000 population. The incidence, mortality, and DALY rates of pancreatic cancer increase with age globally and across all SDI regions, peaking in the 85-89 age group. In high and high-middle SDI regions, the growth rate for males is higher than for females before the age of 85, while females have a higher growth rate after 85. The 75-79 age group exhibits the highest DALY rate in high and high-middle SDI regions, significantly higher than the global and other SDI regions. From 1990 to 2019, the period effects of pancreatic cancer incidence, mortality, and DALY rates have increased significantly worldwide, while remaining almost unchanged in high and high-middle SDI regions. In contrast, period effects have significantly increased in middle, low-middle, and low SDI regions. Cohort effects are more pronounced in middle, low-middle, and low SDI regions. CONCLUSIONS: With the aggravation of population aging, the incidence and mortality rates of pancreatic cancer in the world are increasing, and effective prevention and control measures can be achieved by reducing the exposure of risk factors. The APC model used in our analysis provides a novel approach to understanding the complex trends in the incidence, mortality, and disability-adjusted life years of pancreatic cancer. It can inform the development of targeted interventions to reduce the severe disease burden caused by pancreatic cancer.


Assuntos
Anos de Vida Ajustados por Deficiência , Carga Global da Doença , Saúde Global , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/mortalidade , Incidência , Masculino , Feminino , Idoso , Anos de Vida Ajustados por Deficiência/tendências , Pessoa de Meia-Idade , Adulto , Estudos de Coortes , Saúde Global/estatística & dados numéricos , Idoso de 80 Anos ou mais , Adulto Jovem , Fatores Etários , Adolescente
2.
Exp Brain Res ; 242(1): 205-224, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37994916

RESUMO

Traumatic brain injury (TBI) leads to disturbed brain discharge rhythm, elevated excitability, anxiety-like behaviors, and decreased learning and memory capabilities. Cognitive dysfunctions severely affect the quality of life and prognosis of TBI patients, requiring effective rehabilitation treatment. Evidence indicates that moderate exercise after brain injury decreases TBI-induced cognitive decline. However, the underlying mechanism remains unelucidated. Our results demonstrate that TBI causes cognitive impairment behavior abnormalities and overexpression of Nav1.1, Nav1.3 and Nav1.6 proteins inside the hippocampus of mice models. Three weeks of voluntary running wheel (RW) exercise treatments before or/and post-injury effectively redressed the aberrant changes caused by TBI. Additionally, a 10% exercise-conditioned medium helped recover cell viability, neuronal sodium current and expressions of Nav1.1, Nav1.3 and Nav1.6 proteins across cultured neurons after injury. Therefore, the results validate the neuroprotection induced by voluntary RW exercise treatment before or/and post-TBI. The RW exercise-induced improvement in cognitive behaviors and neuronal excitability could be associated with correcting the Nav1.1, Nav1.3, and Nav1.6 expression levels. The current study proves that voluntary exercise is an effective treatment strategy against TBI. The study also highlights novel potential targets for rehabilitating TBI, including the Navs proteins.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Canais de Sódio Disparados por Voltagem , Humanos , Camundongos , Animais , Qualidade de Vida , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Cognição
3.
BMC Bioinformatics ; 24(1): 192, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170221

RESUMO

BACKGROUND: Synaptogyrin-2 (SYNGR2), as a member of synaptogyrin gene family, is overexpressed in several types of cancer. However, the role of SYNGR2 in pan-cancer is largely unexplored. METHODS: From the TCGA and GEO databases, we obtained bulk transcriptomes, and clinical information. We examined the expression patterns, prognostic values, and diagnostic value of SYNGR2 in pan-cancer, and investigated the relationship of SYNGR2 expression with tumor mutation burden (TMB), microsatellite instability (MSI), immune infiltration, and immune checkpoint (ICP) genes. The gene set enrichment analysis (GSEA) software was used to perform pathway analysis. Besides, we built a nomogram of liver hepatocellular carcinoma patients (LIHC) and validated its prediction accuracy. RESULTS: SYNGR2 was highly expressed in most cancers. The high expression of SYNGR2 significantly reduced the overall survival (OS), disease-specific survival (DSS), disease-free interval (DFI), and progression-free interval (PFI) in multiple types of cancer. Also, receiver operating characteristic (ROC) curve analysis demonstrated that SYNGR2 showed high accuracy in distinguishing cancerous tissues from normal ones. Moreover, SYNGR2 expression was correlated with TMB, MSI, immune scores, and immune cell infiltrations. We also analyzed the association of SYNGR2 with immunotherapy response in LIHC. Finally, a nomogram including SYNGR2 and pathologic T, N, M stage was built and exhibited good predictive power for the OS, DSS, and PFI of LIHC patients. CONCLUSION: Overall, SYNGR2 is a critical oncogene in various tumors. SYNGR2 participates in the carcinogenic progression, and may contribute to the immune infiltration in tumor microenvironment. Our study suggests that SYNGR2 can serve as a predictor related to prognosis in pan-cancer, especially LIHC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sinaptogirinas , Microambiente Tumoral , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Instabilidade de Microssatélites , Oncogenes , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
4.
BMC Genomics ; 24(1): 430, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528394

RESUMO

The tumor immune microenvironment (TIME) of colon cancer (CC) has been associated with extensive immune cell infiltration (IMI). Increasing evidence demonstrated that plasma cells (PC) have an extremely important role in advance of antitumor immunity. Nonetheless, there is a lack of comprehensive analyses of PC infiltration in clinical prognosis and immunotherapy in CC. This study systematically addressed the gene expression model and clinical information of CC patients. Clinical samples were obtained from the TCGA (The Cancer Genome Atlas) databases. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), GSVA, and the MAlignant Tumors using Expression data (ESTIMATE) algorithm were employed to research the potential mechanism and pathways. Immunophenoscore (IPS) was obtained to evaluate the immunotherapeutic significance of risk score. Half maximal inhibitory concentration (IC50) of chemotherapeutic medicine was predicted by employing the pRRophetic algorithm. A total of 513 CC samples (including 472 tumor samples and 41 normal samples) were collected from the TCGA-GDC database. Significant black modules and 313 candidate genes were considered PC-related genes by accessing WGCNA. Five pivotal genes were established through multiple analyses, which revealed excellent prognostic. The underlying correlation between risk score with tumor mutation burden (TMB) was further explored. In addition, the risk score was obviously correlated with various tumor immune microenvironment (TIME). Also, risk CC samples showed various signaling pathways activity and different pivotal sensitivities to administering chemotherapy. Finally, the biological roles of the CD177 gene were uncovered in CC.


Assuntos
Neoplasias do Colo , Medicina , Humanos , Plasmócitos , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Imunoterapia , Algoritmos , Prognóstico , Microambiente Tumoral/genética
5.
BMC Cancer ; 23(1): 1181, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041022

RESUMO

OBJECTIVE: The predictive biomarkers of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) still need to be further explored. This study aims to establish a new immune prognosis biomarker to predict the clinical outcomes of hepatocellular carcinoma patients receiving immune checkpoint inhibitors. METHODS: The subjects of this study were 151 HCC patients receiving ICIs at Harbin Medical University Cancer Hospital from January 2018 to December 2021. This study collected a wide range of blood parameters from patients before treatment and used Cox's regression analysis to identify independent prognostic factors in blood parameters, as well as their ß coefficient. The hepatocellular carcinoma immune prognosis score (HCIPS) was established through Lasso regression analysis and COX multivariate analysis. The cut-off value of HCIPS was calculated from the receiver operating characteristic (ROC) curve. Finally, the prognostic value of HCIPS was validated through survival analysis, stratified analyses, and nomograms. RESULTS: HCIPS was composed of albumin (ALB) and thrombin time (TT), with a cut-off value of 0.64. There were 56 patients with HCIPS < 0.64 and 95 patients with HCIPS ≥ 0.64, patients with low HCIPS were significantly related to shorter progression-free survival (PFS) (13.10 months vs. 1.63 months, P < 0.001) and overall survival (OS) (14.83 months vs. 25.43 months, P < 0.001). HCIPS has also been found to be an independent prognostic factor in this study. In addition, the stratified analysis found a significant correlation between low HCIPS and shorter OS in patients with tumor size ≥ 5 cm (P of interaction = 0.032). The C-index and 95% CI of the nomograms for PFS and OS were 0.730 (0.680-0.779) and 0.758 (0.711-0.804), respectively. CONCLUSIONS: As a new score established based on HCC patients receiving ICIs, HCIPS was significantly correlated with clinical outcomes in patients with ICIs and might serve as a new biomarker to predict HCC patients who cloud benefit from ICIs.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Prognóstico , Biomarcadores
6.
J Sep Sci ; 46(19): e2300108, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37582657

RESUMO

In this study, an efficient, sensitive, and convenient magnetic solid-phase extraction method combined with ultra-high performance liquid chromatography-tandem mass spectrometry (MSPE-UHPLC-MS/MS) was developed for the simultaneous determination of 19 succinate dehydrogenase inhibitor fungicide residues in six different food matrices The synthesized tetraethylenepentamine magnetic graphene oxide nanocomposite showed the advantages of good dispersibility, large specific surface area (113.93 m2 /g) and large pore volume (0.25 cm3 /g), making it an ideal succinate dehydrogenase inhibitor pretreatment adsorbent. The MSPE-UHPLC-MS/MS method showed linearity in the range of 5.0-800.0 µg/kg, with a correlation coefficient (R2 ) > 0.99, and a limit of quantification of 5 µg/kg. The recovery of succinate dehydrogenase inhibitor fungicides was in the range of 71.2%-119.4%. The MSPE method is simple, rapid, and efficient, making it an ideal alternative to sample pretreatment in the determination of trace succinate dehydrogenase inhibitor fungicides in complex matrices.

7.
Sensors (Basel) ; 23(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36992056

RESUMO

The passive optical network (PON) is widely used in optical fiber communication thanks to its low cost and low resource consumption. However, the passiveness brings about a critical problem that it requires manual work to identify the topology structure, which is costly and prone to bringing noise to the topology logs. In this paper, we provide a base solution firstly introducing neural networks for such problems, and based on that solution we propose a complete methodology (PT-Predictor) for predicting PON topology through representation learning on its optical power data. Specifically, we design useful model ensembles (GCE-Scorer) to extract the features of optical power with noise-tolerant training techniques integrated. We further implement a data-based aggregation algorithm (MaxMeanVoter) and a novel Transformer-based voter (TransVoter) to predict the topology. Compared with previous model-free methods, PT-Predictor is able to improve prediction accuracy by 23.1% in scenarios where data provided by telecom operators is sufficient, and by 14.8% in scenarios where data is temporarily insufficient. Besides, we identify a class of scenarios where PON topology does not follow a strict tree structure, and thus topology prediction cannot be effectively performed by relying on optical power data alone, which will be studied in our future work.

8.
Zhongguo Zhong Yao Za Zhi ; 48(2): 465-471, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725236

RESUMO

The present study observed the regulatory effect of total flavonoids of Ziziphora clinopodioides on autophagy and the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) signaling pathways in ApoE~(-/-) mice and explored the mechanism of total flavonoids of Z. clinopodioides against atherosclerosis(AS). ApoE~(-/-) mice were fed on a high-fat diet for eight weeks to induce an AS model. The model mice were randomly divided into a model group, a positive control group, and low-, medium-and high-dose groups of total flavonoids of Z. clinopodioides, while C57BL/6J mice fed on a common diet were assigned to the blank group. The serum and aorta samples were collected after intragastric administration for 12 weeks, and the serum levels of total cholesterol(TC), triglyceride(TG), low density lipoprotein-cholesterol(LDL-C), and high density lipoprotein-cholesterol(HDL-C) were detected by an automatic biochemical analyzer. The serum expression levels of intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1(VCAM-1), matrix metalloproteinase-2(MMP-2), and matrix metalloprotei-nase-9(MMP-9) were detected by enzyme-linked immunosorbent assay(ELISA). Oil red O staining was used to observe the aortic plaque area in mice. Hematoxylin-eosin(HE) staining was used to observe the aortic plaque and pathological changes in mice. The expression of P62 and LC3 in the aorta was detected by the immunofluorescence method. The protein expression of LC3Ⅱ/Ⅰ, Beclin-1, P62, p-PI3K, p-Akt, and p-mTOR in the aorta of mice was detected by Western blot. The results showed that compared with the blank group, the serum levels of TC, TG, LDL-C, ICAM-1, VCAM-1, MMP-2 and MMP-9 in the model group were significantly increased(P<0.01 or P<0.05), the content of HDL-C was decreased(P<0.05), intra-aortic plaque area was enlarged(P<0.01), the expression of LC3 in the aorta was significantly down-regulated, P62 expression was up-regulated(P<0.01 or P<0.05), the expressions of LC3Ⅱ/Ⅰ and Beclin-1 in the aortic lysate were significantly down-regulated, and the expressions of p-PI3K, p-Akt, p-mTOR and P62 were significantly increased(P<0.01). The medium-and high-dose groups of total flavonoids of Z. clinopodioides could reduce the serum levels of TC, TG, LDL-C, ICAM-1, VCAM-1, MMP-2, and MMP-9 in AS model mice(P<0.01 or P<0.05), and increase the content of HDL-C(P<0.01 or P<0.05). The aortic plaque area of mice after middle and high doses of total flavonoids of Z. clinopodioides was significantly reduced(P<0.01), the content of foam cells decrease, and the narrowing of the lumen decreased. The total flavonoids of Z. clinopodioides significantly increased the expression of LC3 in the aorta and the expression of LC3Ⅱ/Ⅰ and Beclin-1 in the lysate, and decreased the expression of P62 in the aorta and the expression of p-PI3K, p-Akt, p-mTOR and P62 in the lysate(P<0.01 or P<0.05). The results showed that the total flavonoids of Z. clinopodioides could improve the content of blood lipids and inflammatory factors, and reduce the generation of foam cells and plaques in aortic tissue, and the mechanism may be related to the regulation of PI3K/Akt/mTOR signaling pathway.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Camundongos , Apolipoproteínas E , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Proteína Beclina-1 , LDL-Colesterol , Molécula 1 de Adesão Intercelular , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Molécula 1 de Adesão de Célula Vascular/genética
9.
Environ Sci Technol ; 56(13): 9806-9815, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35723552

RESUMO

Birnessite (δ-MnO2) is a layered manganese oxide widely present in the environment and actively participates in the transformation of natural organic matter (NOM) in biogeochemical processes. However, the effect of oxygen on the dynamic interface processes of NOM and δ-MnO2 remains unclear. This study systematically investigated the interactions between δ-MnO2 and fulvic acid (FA) under both aerobic and anaerobic conditions. FA was transformed by δ-MnO2 via direct electron transfer and the generated reactive oxygen species (ROS). During the 32-day reaction, 79.8% of total organic carbon (TOC) in solution was removed under anaerobic conditions, unexpectedly higher than that under aerobic conditions (69.8%), suggesting that oxygen limitation was more conducive to the oxidative transformation of FA by δ-MnO2. The oxygen vacancies (OV) on the surface of δ-MnO2 were more exposed under anaerobic conditions, thus promoting the adsorption and transformation of FA as well as regeneration of the active sites. Additionally, the reaction of FA with δ-MnO2 weakened the strongly bonded lattice oxygen (Olatt), and the released Olatt was an important source of ROS. Interestingly, a part of organic carbon (OC) was preserved by forming MnCO3, which might be a novel mechanism for carbon preservation. These findings contribute to an improved understanding of the dynamic interface processes between MnO2 and NOM and provide new insights into the effects of oxygen limitation on the cycling and preservation of OC.


Assuntos
Compostos de Manganês , Óxidos , Carbono , Domínio Catalítico , Compostos de Manganês/química , Óxidos/química , Oxigênio/química , Espécies Reativas de Oxigênio
10.
Indoor Air ; 32(1): e12917, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34477251

RESUMO

Tracer gas experiments were conducted in a 158 m3 room with overhead supply diffusers to study dispersion of contaminants from simulated speaking in physically distanced meeting and classroom configurations. The room was contained within a 237 m3 cell with open plenum return to the HVAC system. Heated manikins at desks and a researcher operating the tracer release apparatus presented 8-9 thermal plumes. Experiments were conducted under conditions of no forced air and neutral, cooled, or heated air supplied at 980-1100 cmh, and with/out 20% outdoor air. CO2 was released at the head of one manikin in each experiment to simulate small (<5 µm diameter) respiratory aerosols. The metric of exposure relative to perfectly mixed (ERM) is introduced to quantify impacts, based on measurements at manikin heads and at three heights in the center and corners of the room. Chilled or neutral supply air provided good mixing with ERMs close to one. Thermal stratification during heating produced higher ERMs at most manikins: 25% were ≥2.5 and the highest were >5× perfectly mixed conditions. Operation of two within-zone air cleaners together moving ≥400 cmh vertically in the room provided enough mixing to mitigate elevated exposure variations.


Assuntos
Poluição do Ar em Ambientes Fechados , Ventilação , Ar Condicionado , Movimentos do Ar , Calefação
11.
Proc Natl Acad Sci U S A ; 116(12): 5558-5563, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30819895

RESUMO

CD3+CD4-CD8- T cells (double-negative T cells; DNTs) have diverse functions in peripheral immune-related diseases by regulating immunological and inflammatory homeostasis. However, the functions of DNTs in the central nervous system remain unknown. Here, we found that the levels of DNTs were dramatically increased in both the brain and peripheral blood of stroke patients and in a mouse model in a time-dependent manner. The infiltrating DNTs enhanced cerebral immune and inflammatory responses and exacerbated ischemic brain injury by modulating the FasL/PTPN2/TNF-α signaling pathway. Blockade of this pathway limited DNT-mediated neuroinflammation and improved the outcomes of stroke. Our results identified a critical function of DNTs in the ischemic brain, suggesting that this unique population serves as an attractive target for the treatment of ischemic stroke.


Assuntos
Isquemia Encefálica/imunologia , Complexo CD3/imunologia , Acidente Vascular Cerebral/imunologia , Subpopulações de Linfócitos T/imunologia , Idoso de 80 Anos ou mais , Animais , Encéfalo/imunologia , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/imunologia , Fator de Necrose Tumoral alfa/metabolismo
12.
Neural Plast ; 2022: 3995227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406589

RESUMO

Voltage-gated sodium channel beta 2 (Nav2.2 or Navß2, coded by SCN2B mRNA), a gene involved in maintaining normal physiological functions of the prefrontal cortex and hippocampus, might be associated with prefrontal cortex aging and memory decline. This study investigated the effects of Navß2 in amyloid-ß 1-42- (Aß1-42-) induced neural injury model and the potential underlying molecular mechanism. The results showed that Navß2 knockdown restored neuronal viability of Aß1-42-induced injury in neurons; increased the contents of brain-derived neurotrophic factor (BDNF), enzyme neprilysin (NEP) protein, and NEP enzyme activity; and effectively altered the proportions of the amyloid precursor protein (APP) metabolites including Aß42, sAPPα, and sAPPß, thus ameliorating cognitive dysfunction. This may be achieved through regulating NEP transcription and APP metabolism, accelerating Aß degradation, alleviating neuronal impairment, and regulating BDNF-related signal pathways to repair neuronal synaptic efficiency. This study provides novel evidence indicating that Navß2 plays crucial roles in the repair of neuronal injury induced by Aß1-42 both in vivo and in vitro.


Assuntos
Disfunção Cognitiva , Canais de Sódio Disparados por Voltagem , Humanos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Neurônios/metabolismo , Canais de Sódio Disparados por Voltagem/metabolismo , Neprilisina/genética , Neprilisina/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo
13.
Indoor Air ; 31(3): 717-729, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33070378

RESUMO

This paper presents pollutant concentrations and performance data for code-required mechanical ventilation equipment in 23 low-income apartments at 4 properties constructed or renovated 2013-2017. All apartments had natural gas cooking burners. Occupants pledged to not use windows for ventilation during the study but several did. Measured airflows of range hoods and bathroom exhaust fans were lower than product specifications. Only eight apartments operationally met all ventilation code requirements. Pollutants measured over one week in each apartment included time-resolved fine particulate matter (PM2.5 ), nitrogen dioxide (NO2 ), formaldehyde and carbon dioxide (CO2 ) and time-integrated formaldehyde, NO2 and nitrogen oxides (NOX ). Compared to a recent study of California houses with code-compliant ventilation, apartments were smaller, had fewer occupants, higher densities, and higher mechanical ventilation rates. Mean PM2.5 , formaldehyde, NO2 , and CO2 were 7.7 µg/m3 , 14.1, 18.8, and 741 ppm in apartments; these are 4% lower, 25% lower, 165% higher, and 18% higher compared to houses with similar cooking frequency. Four apartments had weekly PM2.5 above the California annual outdoor standard of 12 µg/m3 and also discrete days above the World Health Organization 24-hour guideline of 25 µg/m3 . Two apartments had weekly NO2 above the California annual outdoor standard of 30 ppb.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Gás Natural , Material Particulado , Ventilação , Poluentes Atmosféricos , California , Culinária , Monitoramento Ambiental , Formaldeído , Dióxido de Nitrogênio , Pobreza , Respiração Artificial , Emissões de Veículos
14.
Molecules ; 25(16)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32784972

RESUMO

The synthesis of cyclic carbonates from carbon dioxide (CO2) and epoxides is a 100% atom economical reaction and an attractive pathway for CO2 utilisation. Because CO2 is a thermodynamically stable molecule, the use of catalysts is mandatory in reducing the activation energy of the CO2 conversion. Considering environmental compatibility and the high-efficiency catalytic conversion of CO2, there is the strong need to develop green catalysts. Biomass-based catalysts, a type of renewable resource, have attracted considerable attention due to their unique properties-non-toxic, low-cost, pollution-free, etc. In this review, recent advances in the development of biomass-based catalysts for the synthesis of cyclic carbonates by CO2 and epoxides coupling are summarized and discussed in detail. The effect of biomass-based catalysts, functional groups, reaction conditions, and co-catalysts on the catalytic efficiency and selectivity of synthesizing cyclic carbonates process is discussed. We intend to provide a comprehensive understanding of recent experimental and theoretical progress of CO2 and epoxides coupling reaction and pave the way for both CO2 conversion and biomass unitization.


Assuntos
Dióxido de Carbono/química , Carbonatos/química , Compostos de Epóxi/química , Biomassa , Dióxido de Carbono/metabolismo , Carbonatos/síntese química , Catálise , Ciclização , Teoria da Densidade Funcional , Porosidade
15.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31548318

RESUMO

The metabolic inhibition (MI) test is a classic test for the identification of mycoplasmas, used for measuring the growth-inhibiting antibodies directed against acid-producing mycoplasmas, although their mechanism still remains obscure. To determine the major antigens involved in the immune killing of Mycoplasma bovis, we used a pulldown assay with anti-M. bovis antibodies as bait and identified nine major antigens. Among these antigens, we performed the MI test and determined that the growth of M. bovis could be inhibited effectively in the presence of complement by antibodies against specifically membrane protein P81 or UgpB in the presence of complement. Using a complement killing assay, we demonstrated that M. bovis can be killed directly by complement and that antibody-dependent complement-mediated killing is more effective than that by complement alone. Complement lysis and scanning electron microscopy results revealed M. bovis rupture in the presence of complement. Together, these results suggest that the metabolic inhibition of M. bovis is antibody-dependent complement-mediated killing. This study provides new insights into mycoplasma killing by the complement system and may guide future vaccine development studies for the treatment of mycoplasma infection. Furthermore, our findings also indicate that mycoplasmas may be an appropriate new model for studying the lytic activity of membrane attack complex (MAC).


Assuntos
Anticorpos Antibacterianos/imunologia , Proteínas do Sistema Complemento/imunologia , Proteínas de Membrana/imunologia , Infecções por Mycoplasma/veterinária , Mycoplasma bovis/imunologia , Animais , Bovinos , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Microscopia Eletrônica de Varredura , Infecções por Mycoplasma/imunologia , Coelhos
16.
Environ Sci Technol ; 53(16): 9695-9704, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31322867

RESUMO

Much of human exposure to nitrogen oxides (NOx) of ambient origin occurs indoors. Reactions with materials inside building envelopes are expected to influence the amount of ambient NOx that infiltrates indoors. However, envelope penetration factors for ambient NOx constituents have never been measured. Here, we develop and apply methods to measure the penetration factor and indoor loss rates for ambient NOx constituents using time-resolved measurements in an unoccupied apartment unit. Multiple test methods and parameter estimation approaches were tested, including natural and artificial indoor NOx elevation with and without accounting for indoor oxidation reactions. Twelve of 16 tests yielded successful estimates of penetration factors and indoor loss rates. The penetration factor for NO was confirmed to be ∼1 and the mean (±s.d.) NO2 penetration factor was 0.72 ± 0.06 with a mean relative uncertainty of ∼15%. The mean (±s.d.) indoor NO2 loss rate was 0.27 ± 0.12 h-1, ranging 0.06-0.47 h-1, with strong correlations with indoor relative and absolute humidity. Indoor NO loss rates were strongly correlated with the estimated ozone concentration in infiltrating air. Results suggest that envelope penetration factors and loss rates for NOx constituents can be reasonably estimated across a wide range of conditions using these approaches.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Ozônio , Monitoramento Ambiental , Humanos , Óxidos de Nitrogênio
17.
Anal Chem ; 89(10): 5445-5452, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28417633

RESUMO

The interaction between graphene oxide (GO) and DNA is very sensitive to the environment. For example, under acidic conditions, the affinity of GO for DNA is enhanced, weakening the capability of GO to distinguish DNAs with different conformations. This effect has impeded the development of sensitive pH biosensors based on GO-DNA nanosystems. In this work, we systematically studied the affinity between GO and i-motif forming oligonucleotides (IFOs) at different pH values and developed a herring sperm DNA (HSD) treatment method. Using this method, HSD occupies the surface of GO, compromising the attractive force of GO that is significantly enhanced under acidic conditions. As a result, the ability of GO to distinguish between "open" and "closed" IFOs is successfully generalized to a wider pH range. Finally, a pH-sensitive GO-IFO nanosystem was fabricated that showed excellent sensing ability both in vitro and for intracellular pH detection. Because the interaction between GO and DNA is the basis for constructing GO-DNA biosensors, the strategy developed in this work shows great potential to be applied in a variety of other GO-DNA sensing systems.


Assuntos
DNA/química , Grafite/química , Microscopia de Fluorescência , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Nanotecnologia , Oligonucleotídeos/química
18.
Chemistry ; 23(72): 18276-18281, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29071753

RESUMO

Recently, smart DNA hydrogels, which are generally formed by the self-assembly of oligonucleotides or through the cross-linking of oligonucleotide-polymer hybrids, have attracted tremendous attention. However, the difficulties of fabricating DNA hydrogels limit their practical applications. We report herein a novel method for producing pH-responsive hydrogels by rolling circle amplification (RCA). In this method, pH-sensitive cross-linking sites were introduced into the polymeric DNA chains during DNA synthesis. As the DNA sequence can be precisely defined by its template, the properties of such hydrogels can be finely tuned in a very facile way through template design. We have investigated the process of hydrogel formation and pH-responsiveness to provide rationales for functional hydrogel design based on the RCA reaction.


Assuntos
DNA/síntese química , Hidrogéis/química , Oligonucleotídeos/química , Dicroísmo Circular/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura/métodos , Técnicas de Amplificação de Ácido Nucleico , Transição de Fase , Reologia/métodos
19.
Bioorg Med Chem Lett ; 25(10): 2122-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25891105

RESUMO

Using cultured human mast cells (CHMC) the optimization of 2,4-diaminopyrimidine compounds leading to 22, R406 is described. Compound 22 is a potent upstream inhibitor of mast cell degranulation and its mechanism of action is via inhibition of Syk kinase. Compound 22 has significant activity in inhibiting both IgE- and IgG-mediated activation of Fc receptor (FcR) in mast cells and basophils, and in addition inhibits Syk kinase-dependent activity of FcR-mediated activation of monocytes, macrophages, neutrophils, and B cell receptor (BCR)-mediated activation of B lymphocytes. Overall, the biological activity of 22 suggests that it has potential for application as a novel therapeutic for the treatment of an array of autoimmune maladies and hematological malignancies.


Assuntos
Desenho de Fármacos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Pirimidinas/farmacologia , Receptores Fc/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
PLoS One ; 19(5): e0302263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718058

RESUMO

Unsafe behavior among construction personnel poses significant risks in petroleum engineering construction projects. This study addresses this issue through the application of a multi-field coupled homogeneous analysis model. By conducting case analyses of petroleum engineering construction accidents and utilizing the WSR methodology, the influencing factors of unsafe behaviors among construction personnel are systematically categorized into organizational system factors, equipment management factors, and construction personnel factors. Subsequently, employing Risk coupling theory, the study delves into the analysis of these influencing factors, discussing their coupling mechanisms and classifications, and utilizing the N-K model to elucidate the coupling effect among them. Furthermore, a novel approach integrating coupling analysis and multi-agent modeling is employed to establish an evolutionary model of construction personnel's unsafe behavior. The findings reveal that a two-factor control method, concurrently reinforcing equipment and construction personnel management, significantly mitigates unsafe behavior. This study provides valuable insights into the evolution of unsafe behavior among construction personnel and offers a robust theoretical framework for targeted interventions. Significantly, it bears practical implications for guiding safety management practices within petroleum engineering construction enterprises. By effectively controlling unsafe behaviors and implementing targeted safety interventions, it contributes to fostering sustainable development within the petroleum engineering construction industry.


Assuntos
Indústria da Construção , Humanos , Modelos Teóricos , Petróleo , Acidentes de Trabalho/prevenção & controle , Gestão da Segurança
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