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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(9): 914-920, 2024.
Artigo em Chinês | MEDLINE | ID: mdl-39267505

RESUMO

OBJECTIVES: To study the risk factors and prognostic characteristics of pediatric silent lupus nephritis (SLN) with class Ⅲ to V. METHODS: A retrospective study was conducted to collect clinical data from 30 children diagnosed with SLN at the Department of Pediatrics, Second Xiangya Hospital, Central South University, from May 2007 to April 2023. Based on renal pathological classification, the patients were divided into a class Ⅱ group (12 cases) and a class Ⅲ to Ⅴ group (18 cases). The risk factors for the occurrence of class Ⅲ to Ⅴ SLN were analyzed, and the prognostic characteristics were summarized. RESULTS: Among the 30 SLN patients, the median follow-up time was 61.50 months. There were no statistically significant differences in the proportions of patients who discontinued glucocorticoids or achieved low disease activity status, nor in the annual decline rate of estimated glomerular filtration rate (eGFR) between the class Ⅱ and class Ⅲ to V groups (P>0.05). However, three patients in the class Ⅱ group progressed to stage 1 chronic kidney disease (CKD), while eight patients in the class III to V group reached stage 1 CKD, and four patients reached stage 2 CKD. Among the 26 female SLN patients, serum complement C3 levels in the class III to V group were lower than those in the class Ⅱ group (P<0.05). Serum C3 levels in SLN patients, as well as in female SLN patients, were negatively correlated with the fluorescence intensity of IgA, IgG, and C3 immune complexes in the kidneys (P<0.05). Additionally, serum C3 levels in female SLN patients were negatively correlated with the renal pathological activity index (P<0.05). Binary logistic regression analysis indicated that being female and having low serum complement C3 levels were risk factors for the occurrence of class Ⅲ to V SLN in children (P<0.05). CONCLUSIONS: Class Ⅲ to V SLN is not uncommon among SLN children, and there remains a risk of long-term renal function progression. Being female and having low serum complement C3 levels are identified as risk factors for class Ⅲ to V SLN in children.


Assuntos
Complemento C3 , Nefrite Lúpica , Humanos , Feminino , Masculino , Criança , Fatores de Risco , Estudos Retrospectivos , Prognóstico , Complemento C3/análise , Adolescente , Taxa de Filtração Glomerular , Pré-Escolar
2.
Geriatr Nurs ; 60: 121-127, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39241690

RESUMO

Inpatient falls are common adverse events especially for patients with hematologic malignancies. A fall-risk prediction model for patients with hematologic malignancies are still needed. Here we conducted a multicenter study that prospectively included 516 hospitalized patients with hematologic malignancies, and developed a nomogram for fall risk prediction. Patients were divided into the modeling group (n = 389) and the validation group (n = 127). A questionnaire containing sociodemographic factors, general health factors, disease-related factors, medication factors, and physical activity factors was administered to all patients. Logistic regression analysis revealed that peripheral neuropathy, pain intensity, Morse fall scale score, chemotherapy courses, and myelosuppression days were risk factors for falls in patients with hematologic malignancies. The nomogram model had a sensitivity of 0.790 and specificity of 0.800. The calibration curves demonstrated acceptable agreement between the predicted and observed outcomes. Therefore, the nomogram model has promising accuracy in predicting fall risk in patients with hematologic malignancies.

3.
Environ Res ; 262(Pt 1): 119856, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39197485

RESUMO

Artificial biomanufacturing has been developed as a promising biotechnology for water pollution control. Effective bioimmobilization techniques are limited in application because of low productivity and the difficulty in achieving both mechanical strength and biocompatibility. Bioprinting technology, using biomaterials as bioink to enable the rapid on-demand production of bioactive structures, opens a new path for bioimmobilization. In this study, mimicking extracellular polysaccharide and protein of aerobic granular sludge (AGS), sodium alginate (SA) and silk fibroin methacryloyl (SilMA) were developed as the dual-component bioink with a suitable viscosity for bioprinting hydrogel. Interpenetrating network (IPN) hydrogel beads were manufactured using 1.5% (w/v) SA combined with 20% (w/v) SilMA through physical and covalent crosslinking, which exhibited excellent structural stability and bioactivity. The addition of SilMA provided a solution to the poor mechanical stability of SA-Ca hydrogels limited by Ca2+-Na+ ionic exchange. The unique structure of SilMA contributed to the reduction of hydrogel swelling as well as the prevention of SA loss. IPN hydrogels showed a swelling rate of less than 20% compared to the high swelling rate of more than 60% for SA hydrogels. On the other hand, SA controlled the hardening induced by excessive self-assembly of SilMA and improved mass transport in SilMA hydrogels. Compared to IPN hydrogels, SilMA hydrogels experienced a 15% volumetric shrinkage and exhibited a low water content of 92%. Sonication pretreatment of the dual-component bioink not only increased the intermolecular chain entanglement to form IPN, but also led to ß-sheet content in SiMA reaching 46%-48%, which resulted in the formation of stable IPN hydrogels dominated entirely by physical crosslinking. Satisfactory proliferation and viability were achieved for the encapsulated bacteria in IPN hydrogels (µmax 1.49-2.18 d-1). Further, the IPN biohydrogels could maintain structural stability as well as achieve pollutant removal for treating synthetic wastewater with high Na+ concentration of 300 mg/L. The novel SA/SilMA hydrogel bioprinting strategy established in this study offers a new direction for bioimmobilization in water pollution control and other environmental applications.

4.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 823-828, 2024 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-39148386

RESUMO

OBJECTIVES: To study the clinical characteristics of children with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A retrospective analysis was conducted on the clinical data of 25 children diagnosed with AAV at the Second Xiangya Hospital of Central South University from January 2010 to June 2022. RESULTS: Among the AAV children, there were 5 males and 20 females, with a median age of onset of 11.0 years. Involvement of the urinary system was seen in 18 cases (72%); respiratory system involvement in 10 cases (40%); skin involvement in 6 cases (24%); eye, ear, and nose involvement in 5 cases (20%); joint involvement in 4 cases (16%); digestive system involvement in 2 cases (8%). Eleven cases underwent kidney biopsy, with 5 cases (46%) showing focal type, 2 cases (18%) showing crescentic type, 2 cases (18%) showing mixed type, and 2 cases (18%) showing sclerotic type. Immune complex deposits were present in 5 cases (45%). Seven cases reached chronic kidney disease (CKD) stage V, with 2 cases resulting in death. Two cases underwent kidney transplantation. At the end of the follow-up period, 2 cases were at CKD stage II, and 1 case was at CKD stage III. Of the 16 cases of microscopic polyangiitis (MPA) group, 13 (81%) involved the urinary system. Of the 9 cases of granulomatosis with polyangiitis (GPA), 6 cases (66%) had sinusitis. Serum creatinine and uric acid levels were higher in the MPA group than in the GPA group (P<0.05), while red blood cell count and glomerular filtration rate were lower in the MPA group (P<0.05). CONCLUSIONS: AAV is more common in school-age female children, with MPA being the most common clinical subtype. The onset of AAV in children is mainly characterized by renal involvement, followed by respiratory system involvement. The renal pathology often presents as focal type with possible immune complex deposits. Children with MPA often have renal involvement, while those with GPA commonly have sinusitis. The prognosis of children with AAV is poor, often accompanied by renal insufficiency.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Humanos , Feminino , Masculino , Criança , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Estudos Retrospectivos , Adolescente , Pré-Escolar , Insuficiência Renal Crônica/etiologia
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 835-839, 2024 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-39148388

RESUMO

OBJECTIVES: To study the correlation of anti-C1q antibodies with active systemic lupus erythematosus (SLE) and lupus nephritis (LN) in children, as well as their diagnostic value for active SLE and LN. METHODS: A retrospective selection of 90 hospitalized children with SLE at the Children's Medical Center of Second Xiangya Hospital, Central South University from January 2016 to March 2019 as the SLE group, all of whom were tested for anti-C1q antibodies. A control group was formed by collecting 70 hospitalized children with other autoimmune diseases (OAD) during the same period. The differences in anti-C1q antibody levels were compared between two groups.The correlation of anti-C1q antibodies with various indicators of SLE and LN was analyzed, and the diagnostic value of anti-C1q in SLE and LN was evaluated. RESULTS: The serum levels of anti-C1q antibodies in the SLE group were higher than those in the OAD group (P<0.05). The SLE disease activity index score was positively correlated with anti-C1q antibodies (rs=0.371, P<0.001) and positively correlated with anti-double-stranded DNA antibodies (rs=0.370, P<0.001). The sensitivity and specificity of anti-C1q antibodies for diagnosing active SLE were 89.90% and 53.90%, respectively, with an area under the curve of 0.720 (P<0.05) and a critical value of 5.45 U/mL. The sensitivity and specificity of anti-C1q antibody levels for diagnosing active LN were 58.50% and 85.00%, respectively, with an area under the curve of 0.675 (P<0.05) and a critical value of 22.05 U/mL. CONCLUSIONS: Anti-C1q antibodies can serve as non-invasive biomarkers for evaluating the activity of SLE or predicting the activity of LN in children.


Assuntos
Complemento C1q , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Complemento C1q/imunologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/sangue , Feminino , Criança , Masculino , Lúpus Eritematoso Sistêmico/imunologia , Estudos Retrospectivos , Adolescente , Autoanticorpos/sangue , Pré-Escolar , Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia
6.
Water Res ; 263: 122173, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39111213

RESUMO

Wastewater treatment plants face significant challenges in transitioning from energy-intensive systems to carbon-neutral, energy-saving systems, and a large amount of chemical energy in wastewater remains untapped. Iron is widely used in modern wastewater treatment. Research shows that leveraging the coupled redox relationship of iron and carbon can redirect this energy (in the form of carbon) towards resource utilization. Therefore, re-examining the application of iron in existing wastewater carbon processes is particularly important. In this review, we investigate the latest research progress on iron for wastewater carbon flow restructuring. During the iron-based chemically enhanced primary treatment (CEPT) process, organic carbon is captured into sludge and its bioavailability is enhanced through iron-based advanced oxidation processes (AOP) pretreatment, further being recovered or upgraded to value-added products in anaerobic biological processes. We discuss the roles and mechanisms of iron in CEPT, AOP, anaerobic biological processes, and biorefining in driving organic carbon conversion. The dosage of iron, as a critical parameter, significantly affects the recovery and utilization of sludge carbon resources, particularly by promoting effective electron transfer. We propose a pathway for beneficial conversion of wastewater organic carbon driven by iron and analyze the benefits of the main products in detail. Through this review, we hope to provide new insights into the application of iron chemicals and current wastewater treatment models.


Assuntos
Carbono , Ferro , Eliminação de Resíduos Líquidos , Águas Residuárias , Ferro/química , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Oxirredução , Esgotos/química
7.
Risk Anal ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39128862

RESUMO

Urban flooding is among the costliest natural disasters worldwide. Timely and effective rescue path planning is crucial for minimizing loss of life and property. However, current research on path planning often fails to adequately consider the need to assess area risk uncertainties and bypass complex obstacles in flood rescue scenarios, presenting significant challenges for developing optimal rescue paths. This study proposes a deep reinforcement learning (RL) algorithm incorporating four main mechanisms to address these issues. Dual-priority experience replays and backtrack punishment mechanisms enhance the precise estimation of area risks. Concurrently, random noisy networks and dynamic exploration techniques encourage the agent to explore unknown areas in the environment, thereby improving sampling and optimizing strategies for bypassing complex obstacles. The study constructed multiple grid simulation scenarios based on real-world rescue operations in major urban flood disasters. These scenarios included uncertain risk values for all passable areas and an increased presence of complex elements, such as narrow passages, C-shaped barriers, and jagged paths, significantly raising the challenge of path planning. The comparative analysis demonstrated that only the proposed algorithm could bypass all obstacles and plan the optimal rescue path across nine scenarios. This research advances the theoretical progress for urban flood rescue path planning by extending the scale of scenarios to unprecedented levels. It also develops RL mechanisms adaptable to various extremely complex obstacles in path planning. Additionally, it provides methodological insights into artificial intelligence to enhance real-world risk management.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39119898

RESUMO

OBJECTIVES: Mechanisms of non-typhoidal Salmonella (NTS) resistance to azithromycin have rarely been reported. Here we investigate the epidemiology and genetic features of 10 azithromycin-resistant NTS isolates. METHODS: A total of 457 NTS isolates were collected from a tertiary hospital in Guangzhou. We performed antimicrobial susceptibility tests, conjugation experiments, efflux pump expression tests, whole-genome sequencing and bioinformatics analysis to conduct the study. RESULTS: The results showed that 10 NTS isolates (2.8%) were resistant to azithromycin with minimum inhibitory concentration values ranging from 128 to 512 mg/L and exhibited multidrug resistance. The phylogenetic tree revealed that 5 S. London isolates (AR1-AR5) recognized at different times and departments were closely related [3-74 single-nucleotide polymorphisms (SNPs)] and 2 S. Typhimurium isolates (AR7 and AR8) were clones (<3 SNPs) at 3-month intervals. The azithromycin resistance was conferred by mph(A) gene found on different plasmids, including IncFIB, IncHI2, InFII, IncC and IncI plasmids. Among them, IncFIB, InFII and IncHI2 plasmids carried different IS26-class 1 integron (intI1) arrangement patterns that mediated multidrug resistance transmission. Conjugative IncC plasmid encoded resistance to ciprofloxacin, ceftriaxone and azithromycin. Furthermore, phylogenetic analysis demonstrated that mph(A)-positive plasmids closely related to 10 plasmids in this study were mainly discovered from NTS, Escherichia coli, Klebsiella pneumonia and Enterobacter hormaechei. The genetic environment of mph(A) in 10 NTS isolates was IS26-mph(A)-mrx(A)-mphR(A)-IS6100/IS26 that co-arranged with intI1 harbour multidrug-resistant (MDR) gene cassettes on diverse plasmids. CONCLUSIONS: These findings highlighted that the dissemination of these plasmids carrying mph(A) and various intI1 MDR gene cassettes would seriously restrict the availability of essential antimicrobial agents for treating NTS infections.

9.
Nat Prod Res ; : 1-6, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980006

RESUMO

A new polyketide, mauritone A (1) with six known polyketides curvulone B (2), curvularin (3), 12-oxocurvularin (4), (10E,15S)-10,11-dehydrocurvularin (5), (11R,15S)-11-hydroxycurvularin (6), and (11S,15S)-11-hydroxycurvularin (7) were isolated from the fungal-bacterial symbiont Aspergillus spelaeus GXIMD 04541/Sphingomonas echinoides GXIMD 04532 derived from Mauritia arabica. Their structures were elucidated by extensive spectral analysis. All compounds (1-7) were evaluated for their anti-inflammatory effects. The inhibitory effects of 4, 5, and 7 on nitric oxide (NO) production were found to be significant, with IC50 values of 5.5 ± 0.26, 2.0 ± 0.31, and 8.3 ± 0.62 µM, respectively, surpassing that of the positive control quercetin (10.6 ± 0.64 µM). Compounds 3 and 6 exhibited moderate inhibition of NO, with IC50 values of 18.6 ± 0.53 and 12.7 ± 0.45 µM, respectively.

10.
J Cell Biol ; 223(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38990714

RESUMO

Dermal fibroblasts deposit type I collagen, the dominant extracellular matrix molecule found in skin, during early postnatal development. Coincident with this biosynthetic program, fibroblasts proteolytically remodel pericellular collagen fibrils by mobilizing the membrane-anchored matrix metalloproteinase, Mmp14. Unexpectedly, dermal fibroblasts in Mmp14-/- mice commit to a large-scale apoptotic program that leaves skin tissues replete with dying cells. A requirement for Mmp14 in dermal fibroblast survival is recapitulated in vitro when cells are embedded within, but not cultured atop, three-dimensional hydrogels of crosslinked type I collagen. In the absence of Mmp14-dependent pericellular proteolysis, dermal fibroblasts fail to trigger ß1 integrin activation and instead actuate a TGF-ß1/phospho-JNK stress response that leads to apoptotic cell death in vitro as well as in vivo. Taken together, these studies identify Mmp14 as a requisite cell survival factor that maintains dermal fibroblast viability in postnatal dermal tissues.


Assuntos
Apoptose , Sobrevivência Celular , Fibroblastos , Metaloproteinase 14 da Matriz , Animais , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/genética , Fibroblastos/metabolismo , Camundongos , Camundongos Knockout , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Integrina beta1/metabolismo , Integrina beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Derme/metabolismo , Derme/citologia , Células Cultivadas , Matriz Extracelular/metabolismo , Camundongos Endogâmicos C57BL , Pele/metabolismo
11.
Environ Sci Technol ; 58(27): 12225-12236, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38885124

RESUMO

Nanoscale zerovalent iron synthesized using borohydride (B-NZVI) has been widely applied in environmental remediation in recent decades. However, the contribution of boron in enhancing the inherent reactivity of B-NZVI and its effectiveness in removing hexavalent chromium [Cr(VI)] have not been well recognized and quantified. To the best of our knowledge, herein, a core-shell structure of B-NZVI featuring an Fe-B alloy shell beneath the iron oxide shell is demonstrated for the first time. Alloyed boron can reduce H+, contributing to more than 35.6% of H2 generation during acid digestion of B-NZVIs. In addition, alloyed B provides electrons for Fe3+ reduction during Cr(VI) removal, preventing in situ passivation of the reactive particle surface. Meanwhile, the amorphous oxide shell of B-NZVI exhibits an increased defect density, promoting the release of Fe2+ outside the shell to reduce Cr(VI), forming layer-structured precipitates and intense Fe-O bonds. Consequently, the surface-area-normalized capacity and surface reaction rate of B-NZVI are 6.5 and 6.9 times higher than those of crystalline NZVI, respectively. This study reveals the importance of alloyed B in Cr(VI) removal using B-NZVI and presents a comprehensive approach for investigating electron pathways and mechanisms involved in B-NZVIs for contaminant removal.


Assuntos
Boroidretos , Boro , Ferro , Ferro/química , Boroidretos/química , Boro/química , Cromo/química , Elétrons , Ligas/química
12.
Mol Neurobiol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850348

RESUMO

Dysbiosis of the gut microbiota is closely associated with neurodegenerative diseases, including Huntington's disease (HD). Gut microbiome-derived metabolites are key factors in host-microbiome interactions. This study aimed to investigate the crucial gut microbiome and metabolites in HD and their correlations. Fecal and serum samples from 11 to 26 patients with HD, respectively, and 16 and 23 healthy controls, respectively, were collected. The fecal samples were used for shotgun metagenomics while the serum samples for metabolomics analysis. Integrated analysis of the metagenomics and metabolomics data was also conducted. Firmicutes, Bacteroidota, Proteobacteria, Uroviricota, Actinobacteria, and Verrucomicrobia were the dominant phyla. At the genus level, the presence of Bacteroides, Faecalibacterium, Parabacteroides, Alistipes, Dialister, and Christensenella was higher in HD patients, while the abundance of Lachnospira, Roseburia, Clostridium, Ruminococcus, Blautia, Butyricicoccus, Agathobaculum, Phocaeicola, Coprococcus, and Fusicatenibacter decreased. A total of 244 differential metabolites were identified and found to be enriched in the glycerophospholipid, nucleotide, biotin, galactose, and alpha-linolenic acid metabolic pathways. The AUC value from the integrated analysis (1) was higher than that from the analysis of the gut microbiota (0.8632). No significant differences were found in the ACE, Simpson, Shannon, Sobs, and Chao indexes between HD patients and controls. Our study determined crucial functional gut microbiota and potential biomarkers associated with HD pathogenesis, providing new insights into the role of the gut microbiota-brain axis in HD occurrence and development.

13.
Int Urogynecol J ; 35(6): 1163-1170, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38695902

RESUMO

INTRODUCTION AND HYPOTHESIS: The potential predictors of pelvic floor reconstruction surgery hypothermia remain unclear. This prospective cohort study was aimed at identifying these predictors and evaluating the outcomes associated with perioperative hypothermia. METHODS: Elderly patients undergoing pelvic floor reconstruction surgery were consecutively enrolled from April 2023 to September 2023. Perioperative temperature was measured at preoperative (T1), every 15 min after the start of anesthesia (T2), and 15 min postoperative (T3) using a temperature probe. Perioperative hypothermia was defined as a core temperature below 36°C at any point during the procedure. Multivariate logistic regression analysis was conducted to determine factors associated with perioperative hypothermia. RESULTS: A total of 229 patients were included in the study, with 50.7% experiencing hypothermia. Multivariate analysis revealed that the surgical method involving pelvic floor combined with laparoscopy, preoperative temperature < 36.5°C, anesthesia duration ≥ 120 min, and the high levels of anxiety were significantly associated with perioperative hypothermia. The predictive value of the multivariate model was 0.767 (95% CI, 0.706 to 0.828). CONCLUSIONS: This observational prospective study identified several predictive factors for perioperative hypothermia in elderly patients during pelvic floor reconstruction surgery. Strategies aimed at preventing perioperative hypothermia should target these factors. Further studies are required to assess the effectiveness of these strategies, specifically in elderly patients undergoing pelvic floor reconstruction surgery.


Assuntos
Hipotermia , Diafragma da Pelve , Humanos , Hipotermia/etiologia , Hipotermia/prevenção & controle , Idoso , Feminino , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/efeitos adversos , Período Perioperatório , Fatores de Risco , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Laparoscopia , Prolapso de Órgão Pélvico/cirurgia
14.
JACS Au ; 4(5): 1892-1900, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38818067

RESUMO

Understanding the nonequilibrium transformation of nanocatalysts under reaction conditions is important because metastable atomic structures may be created during the process, which offers unique activities in reactions. Although reshaping of metal nanoparticles (NPs) under reaction conditions has been widely recognized, the dynamic reshaping process has been less studied at the atomic scale. Here, we develop an atomistic kinetic Monte Carlo model to simulate the complete reshaping process of Pt nanoparticles in a CO environment and reveal the in situ formation of atomic clusters on the NP surface, a new type of active site beyond conventional understanding, boosting the reactivities in the CO oxidation reaction. Interestingly, highly active peninsula and inactive island clusters both form on the (111) facets and interchange in varying states of dynamic equilibrium, which influences the catalytic activities significantly. This study provides new fundamental knowledge of nanocatalysis and new guidance for the rational design of nanocatalysts.

15.
J Am Chem Soc ; 146(20): 14267-14277, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717595

RESUMO

Converting CO2 to synthetic hydrocarbon fuels is of increasing interest. In light of progress in electrified CO2 to ethylene, we explored routes to dimerize to 1-butene, an olefin that can serve as a building block to ethylene longer-chain alkanes. With goal of selective and active dimerization, we investigate a series of metal-organic frameworks having bimetallic catalytic sites. We find that the tunable pore structure enables optimization of selectivity and that periodic pore channels enhance activity. In a tandem system for the conversion of CO2 to 1-C4H8, wherein the outlet cathodic gas from a CO2-to-C2H4 electrolyzer is fed directly (via a dehumidification stage) into the C2H4 dimerizer, we study the highest-performing MOF found herein: M' = Ru and M″ = Ni in the bimetallic two-dimensional M'2(OAc)4M″(CN)4 MOF. We report a 1-C4H8 production rate of 1.3 mol gcat-1 h-1 and a C2H4 conversion of 97%. From these experimental data, we project an estimated cradle-to-gate carbon intensity of -2.1 kg-CO2e/kg-1-C4H8 when CO2 is supplied from direct air capture and when the required energy is supplied by electricity having the carbon intensity of wind.

16.
Aquat Toxicol ; 272: 106962, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797068

RESUMO

Diisobutyl phthalate (DiBP), is widely chemical replacement for Dibutyl phthalate (DBP). Although DBP and DiBP have been detected in surface water worldwide, few studies to date have systematically assessed the risks of DBP and its alternatives to aquatic organisms. The present study compared DBP and DiBP for their individual and joint toxicity as well as thyroid hormone levels in zebrafish embryo. Transcripts of key genes related to the hypothalamic-pituitary-thyroid (HPT) axis were investigated in developing zebrafish larvae by application of real time polymerase chain reaction. The median half-lethal concentrations of DBP and DiBP to zebrafish at 96 h were 0.545 mg L-1 and 1.149 mg L-1, respectively. The joint toxic effect of DBP-DiBP (0.25-0.53 mg L-1) with the same ratio showed a synergistic effect. Thyroid hormones levels increased with exposure to 10 µg L-1 of DBP or 50 µg L-1 of DiBP, and exposure to both compounds significantly increased thyroid gland-specific transcription of thyroglobulin gene (tg), hyronine deiodinase (dio2), and transthyretin (ttr), indicating an adverse effect associated with the HPT axis. Molecular docking results indicated that DBP (-7.10 kcal/M and -7.53 kcal/M) and DiBP (-6.63 kcal/M and -7.42 kcal/M) had the same docking energy with thyroid hormone receptors. Our data facilities an understand of potential harmful effects of DBP and its alternative (DiBP).


Assuntos
Dibutilftalato , Embrião não Mamífero , Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/genética , Dibutilftalato/toxicidade , Dibutilftalato/análogos & derivados , Poluentes Químicos da Água/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Ácidos Ftálicos/toxicidade , Hormônios Tireóideos/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/genética , Glândula Tireoide/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos
17.
Water Res ; 258: 121785, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38761595

RESUMO

The city-river-reservoir system is an important system for safeguarding drinking water. Phthalic acid esters (PAEs) are emerging contaminants in drinking water sources that are gaining attention, and they could pose risks to human health and aquatic organisms. In this study, field studies that lasted four years were conducted to analyze the concentrations, spatial-temporal distribution, and removal effects of six PAEs. The total concentrations of the Σ6PAEs in the water and sediment samples were 0.2-7.4 µg L-1 (mean: 1.3 µg L-1) and 9.2-9594.1 ng g-1 (mean: 847.5 ng g-1), respectively. Di-n-butyl phthalate (DBP) and, bis(2-ethylhexyl) phthalate (DEHP) were the predominant congeners, accounting for 57.2 % in the water samples and 94.1 % in the sediment samples. The urban area contributed 72 % of the PAEs in the system. A significant removal effect of PAEs was observed in the wetland, with a removal rate of 40.2 %. The partitioning of PAEs between the water and sediment was attributed to the removal of dimethyl phthalate and diethyl phthalate that occurred during the water phase, while the removal of DBP and DEHP primarily occurred during the sediment phase. The ecological risk calculation based on the sensitivity distribution model indicated that DBP (HQwater = 0.19, HQsediment = 0.46) and DEHP (HQwater = 0.20, HQsediment = 0.13) possessed moderate risks according to some water and sediment samples. The ecological projects were verified to be effective engineering strategies to reduce ecological risk in the drinking water source.


Assuntos
Ésteres , Ácidos Ftálicos , Rios , Poluentes Químicos da Água , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Rios/química , Ésteres/análise , Monitoramento Ambiental , Sedimentos Geológicos/química
18.
Food Chem X ; 22: 101300, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38571574

RESUMO

The composition of volatile compounds in beer is crucial to the quality of beer. Herein, we identified 23 volatile compounds, namely, 12 esters, 4 alcohols, 5 acids, and 2 phenols, in nine different beer types using GC-MS. By performing PCA of the data of the flavor compounds, the different beer types were well discriminated. Ethyl caproate, ethyl caprylate, and phenylethyl alcohol were identified as the crucial volatile compounds to discriminate different beers. PLS regression analysis was performed to model and predict the contents of six crucial volatile compounds in the beer samples based on the characteristic wavelength of the FTIR spectrum. The R2 value of each sample in the prediction model was 0.9398-0.9994, and RMSEP was 0.0122-0.7011. The method proposed in this paper has been applied to determine flavor compounds in beer samples with good consistency compared with GC-MS.

19.
J Am Chem Soc ; 146(12): 8641-8649, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38470826

RESUMO

Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.

20.
Endokrynol Pol ; 75(1): 61-70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38497391

RESUMO

INTRODUCTION: Gestational diabetes mellitus (GDM) is the most common metabolic disease in pregnancy. However, studies of activating molecule of Beclin1-regulated autophagy (Ambra1) affecting the insulin substrate receptor 1/phosphatidylinositol 3 kinase/protein kinase B (IRS-1/PI3K/Akt) signalling pathway in GDM have not been reported. The aim of the study was to detect the difference of Ambra1 expression in the placenta of normal pregnant women and GDM patients. MATERIAL AND METHODS: An in vitro model of gestational diabetes mellitus was established by inducing HTR8/Svneo cells from human chorionic trophoblast layer with high glucose. The changes of cell morphology were observed by inverted microscope, and the expression levels of Ambra1 gene and protein in model cells were detected. After this, Ambra1 gene was silenced by shRNA transfection, and PI3K inhibitor was added to detect changes in Ambra1, autophagy, and insulin (INS) signalling pathways. RESULTS: The protein expression levels of Ambra1, Bcl-2 interacting protein (Beclin-1), and microtubule-associated proteins 1A/1B light chain 3B (LC3-II) in the placentas of GDM pregnant women were higher than those of normal pregnant women. High glucose induces morphological changes in HTR8/Svneo cells and increases Ambra1 transcription and translation levels. sh-Ambra1 increased survival of HTR8/SvNEO-HG cells and inhibited Ambra1, Beclin1, and LC3-II transcription and translation levels. Also, sh-Ambra1 increased IRS-1/PI3K/Akt protein phosphorylation levels and inhibited the IRS-1/PI3K/Akt signalling pathway and its resulting autophagy. CONCLUSIONS: sh-Ambra1 increased IRS-1/PI3K/Akt protein phosphorylation levels to reduce autophagy in gestational diabetes.


Assuntos
Diabetes Gestacional , Feminino , Humanos , Gravidez , Autofagia , Proteína Beclina-1 , Diabetes Gestacional/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
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