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1.
Phytopathology ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831556

RESUMO

Fusarium head blight (FHB) caused by Fusarium graminearum is a significant pathogen affecting wheat crops. During the infection process, effector proteins are secreted to modulate plant immunity and promote infection. The toxin deoxynivalenol (DON) is produced in infected wheat grains, posing a threat to human and animal health. Serine carboxypeptidases (SCPs) belong to the α/ß hydrolase family of proteases and are widely distributed in plant and fungal vacuoles as well as animal lysosomes. Research on SCPs mainly focuses on the isolation, purification of a small number of fungi as well as their study in plants.However, their functions in F. graminearum, a fungal pathogen, remain relatively unknown. In this study, the biological functions of the FgSCP gene in F. graminearum were investigated. The study revealed that mutations in FgSCP affected nutritional growth, sexual reproduction, and stress tolerance of F. graminearum. Furthermore, the deletion of FgSCP resulted in reduced pathogenicity and hindered the biosynthesis of DON. The upregulation of FgSCP expression three days after infection indicated its involvement in host invasion, possibly acting as a "smokescreen" to deceive the host and suppress the expression of host defensive genes. Subsequently, we confirmed the secretion ability of FgSCP and its ability to inhibit the cell death induced by INF1 in Nicotiana. benthamiana cells, indicating its potential role as an effector protein in suppressing plant immune responses and promoting infection. In summary, we have identified FgSCP as an essential effector protein in F. graminearum, playing critical roles in growth, virulence, secondary metabolism, and host invasion.

2.
Front Plant Sci ; 15: 1356723, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835863

RESUMO

Fusarium crown rot (FCR) is an important and devastating disease of wheat (Triticum aestivum) caused by the fungus Fusarium pseudograminearum and related pathogens. Using two distinct susceptible cultivars, we investigated the isolation frequencies of F. pseudograminearum and quantified its biomass accumulation and the levels of the associated toxins deoxynivalenol (DON) and DON-3-glucoside (D3G) in inoculated field-grown wheat plants. We detected F. pseudograminearum in stem, peduncle, rachis, and husk tissues, but not in grains, whereas DON and D3G accumulated in stem, rachis, husk, and grain tissues. Disease severity was positively correlated with the frequency of pathogen isolation, F. pseudograminearum biomass, and mycotoxin levels. The amount of F. pseudograminearum biomass and mycotoxin contents in asymptomatic tissue of diseased plants were associated with the distance of the tissue from the diseased internode and the disease severity of the plant. Thus, apparently healthy tissue may harbor F. pseudograminearum and contain associated mycotoxins. This research helps clarify the relationship between F. pseudograminearum occurrence, F. pseudograminearum biomass, and mycotoxin accumulation in tissues of susceptible wheat cultivars with or without disease symptoms, providing information that can lead to more effective control measures.

3.
Clin Transl Oncol ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922538

RESUMO

OBJECTIVE: This meta-analysis aims to evaluate the safety and efficacy of restarting immune checkpoint inhibitors (ICIs) in patients with non-small cell lung cancer (NSCLC) after experiencing immune-related adverse events (irAEs). METHODS: A comprehensive search of PubMed, Web of Science, Embase, and the Cochrane Library was conducted to identify studies investigating the safety and efficacy of restarting ICIs in NSCLC patients after irAEs. Outcome measures, including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) after ICI restarting, were extracted. Meta-analysis was performed using the R meta-package. RESULTS: Four studies involving a total of 326 subjects were included, comprising 137 patients who restarted ICI treatment after irAEs and 189 patients who did not restart ICI treatment. The results revealed that ICI restarting was associated with an increased ORR (OR = 2.36, 95% CI 1.49-3.84), prolonged PFS (HR = 0.60, 95% CI 0.42-0.86), and prolonged OS (HR = 0.65, 95% CI 0.43-0.99) compared to non-restarting. The incidence of irAEs after ICI restarting was 45% (95% CI 0.27-0.63). CONCLUSION: Restarting ICI treatment after discontinuation due to previous irAEs appears to be a reasonable option for NSCLC patients. However, a comprehensive assessment of the potential benefits and risks to individual patients is crucial, and close monitoring of irAEs is warranted.

4.
Am Heart J Plus ; 39: 100369, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38510996

RESUMO

Study objective: This study aimed to identify factors associated with delayed oral anticoagulant (OAC) treatment initiation among atrial fibrillation (AF) patients in United States (US) clinical practice. Participants: Medicare beneficiaries newly diagnosed with AF without moderate-to-severe mitral stenosis or a mechanical heart valve, were aged ≥65 years and prescribed OAC on or after 10/1/2015 through 2019 were included. Delayed and early OAC initiation were defined as >3 months and 0-3 months initiation from first AF diagnosis, respectively. Main outcome measures: Association between delayed OAC initiation and patient demographics, clinical and index OAC coverage and formulary characteristics was examined using multivariable logistic regression. Results: A total of 446,441 patients met the inclusion criteria; 30.0 % (N = 131,969) were identified as delayed and 70.0 % (N = 314,472) as early OAC initiation. Median age for both cohorts was 78 years. In the early and delayed OAC cohorts, 47.1 % and 47.6 % were male and 88.8 % and 86.6 %, were White, respectively. Factors associated with delayed OAC initiation (odds ratio; 95 % confidence interval) included Black race (1.29; 1.25 to 1.33), west region (1.29; 1.26 to 1.32), comorbidities such as dementia (1.27; 1.23 to 1.30), recent bleeding hospitalization (1.22; 1.18 to 1.27), prior authorization (1.69; 1.66 to 1.71), tier 4 formulary for index OAC at AF diagnosis (1.26; 1.22 to 1.30). Conclusion: Our study revealed that nearly one-third of Medicare patients with AF experienced delayed OAC initiation. Key patient characteristics found to be associated with delayed OAC initiation included race and ethnicity, comorbidities, and formulary restrictions.

5.
Front Oncol ; 13: 1287628, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111524

RESUMO

Background: Immune checkpoint inhibitors (ICIs) have changed the therapeutic options for extensive-stage small-cell lung cancer (ES-SCLC). In this real-world study, we analyzed the treatment patterns in patients with ES-SCLC and evaluated the efficacy of chemotherapy combined with immunotherapy as first-line therapy. Methods: A retrospective analysis was performed on patients with ES-SCLC who received treatment at China-Japan Friendship Hospital (Beijing, China) between August 1, 2020, and April 30, 2023. The treatment patterns appeared in the form of Sunburst Chart and Sankey diagram. The survival analyses were conducted by Kaplan-Meier curves. Results: A total of 157 patients with ES-SCLC were retrospectively included. According to first-line therapy, patients were divided into the chemotherapy (CT) group (n=82) and chemo-immunotherapy (CIT) group (n=75). The median treatment lines were 2[1, 2] and cycles were 8[5, 12], respectively. 82 patients received the second line of therapy, followed by 37 for the third, 15 for the fourth, 11 for the fifth, and 5 for the sixth. Overall, the treatment patterns involved 11 options including 12 chemotherapy regimens, 11 ICIs, and 4 targeted agents. The second-line treatment pattern had the most options (9) and regimens (43). In the first 3 lines, chemotherapy was the largest proportion of treatment options. The addition of ICIs prolonged progression-free survival from 6.77 (95% confidence interval [CI], 6.00-7.87) to 7.33 (95% CI, 6.03-9.80) months (hazard ratio [HR]=0.67, 95% CI, 0.47-0.95; P=0.025), overall survival from 12.97 (10.90-23.3) to 14.33 (12.67-NA) months without statistically significant difference (HR=0.86, 95% CI, 0.55-1.34; P=0.505). Conclusion: The treatment options of patients with ES-SCLC are more diversified. Combination therapy is the current trend, where chemotherapy is the cornerstone. Meanwhile, ICIs participate in almost all lines of treatment. However, the clinical efficacy remains barely satisfactory. We are urgently expecting more breakthrough therapies except immunology will be applied in the clinic.

6.
J Fungi (Basel) ; 9(10)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37888265

RESUMO

Protein disulfide isomerase (PDI) is a member of the thioredoxin (Trx) superfamily with important functions in cellular stability, ion uptake, and cellular differentiation. While PDI has been extensively studied in humans and animals, its role in fungi remains relatively unknown. In this study, the biological functions of FgEps1, a disulfide bond isomerase in the fungal pathogen Fusarium graminearum, were investigated. It was found that FgEps1 mutation affected nutritional growth, asexual and sexual reproduction, and stress tolerance. Additionally, its deletion resulted in reduced pathogenicity and impaired DON toxin biosynthesis. The involvement of FgEps1 in host infection was also confirmed, as its expression was detected during the infection period. Further investigation using a yeast signal peptide secretion system and transient expression in Nicotiana benthamiana showed that FgEps1 suppressed the immune response of plants and promoted infection. These findings suggest that virulence factor FgEps1 plays a crucial role in growth, development, virulence, secondary metabolism, and host infection in F. graminearum.

7.
Inorg Chem ; 62(30): 12130-12137, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37459403

RESUMO

Mn4+-activated fluoride red phosphors exhibit excellent luminescence properties. However, a persistent technical challenge lies in their poor moisture resistance. Current strategies primarily focus on surface modifications to effectively shield the [MnF6]2- species from water molecules while neglecting the underlying structure of the fluoride matrix. In this study, we introduce Si4+ and Ge4+ ions into the K2TiF6:Mn4+ crystal to create covalent fluoride solid solutions, namely, K2Ti1-xSixF6:Mn4+ and K2Ti1-yGeyF6:Mn4+, through crystal reconstruction. The findings reveal that the incorporation of Si4+ leads to increased particle size, enhanced luminescence intensity (by 40%), and improved moisture resistance. Furthermore, after undergoing 1000 h of aging at high temperature and high humidity conditions, the white LED featuring the K2Ti0.97Si0.03F6:Mn4+ phosphor demonstrates remarkable durability by retaining 90% of its initial luminous efficacy. This performance surpasses that of the device utilizing the K2TiF6:Mn4+ phosphor, which only retains 74% of its original efficacy. The crystal reconstruction method and covalent enhancement strategy proposed in this work contribute to enhancing the luminescence efficiency and moisture resistance of fluoride phosphors, thereby offering new insights for advancing the development of high-efficiency and highly stable white light LED devices.

8.
Chem Commun (Camb) ; 59(13): 1789-1792, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36722415

RESUMO

A novel responsive hydrogel exhibiting self-reinforcement and self-healing capacity was developed based on the hydrophobic aggregation of strained 1,2-dithiolane rings. Oligomerization of 1,2-dithiolane within hydrophobic domains under UV irradiation not only reinforced the hydrogel but also maintained its dynamic cross-linked nature by converting the intraring dynamic S-S bond to an outer one.

9.
Front Microbiol ; 13: 1045796, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439801

RESUMO

With the increase of temperature in the winter wheat-growing regions in China, the high-temperature-resistant Blumeria graminis f. sp. tritici (Bgt) isolates developed in the fields. To clarify the key infection stages and the roles of heat shock protein (HSP) genes of high-temperature-resistant Bgt isolates defending high temperature, 3 high-temperature-resistant and 3 sensitive Bgt isolates were selected from 55 isolates after determination of temperature sensitivity. And then they were used to investigate the infection stages and the expression levels of HSP genes, including Bgthsp60, Bgthsp70, Bgthsp90, and Bgthsp104, at 18°C and 25°C. The formation frequency of abnormal appressoria and inhibition rate of haustoria formation of high-temperature-resistant isolates at 25°C were lower than those of high-temperature-sensitive isolates, while major axis of microcolonies of high-temperature-resistant isolates was higher than those of high-temperature-sensitive isolates at 25°C. The results indicated that haustoria formation and hyphal expansion were the key infection stages of defense against heat stress in high-temperature-resistant isolates. Further analyses of HSP genes found the expression levels of Bgthsp60 and Bgthsp70c were upregulated at 24 and 72 h post-inoculation in high-temperature-resistant isolates, while no significant difference was observed for Bgthsp90 and Bgthsp104 genes. Taken together, the basis of high-temperature-resistant Bgt isolates is associated with induced expression of Bgthsp60 and Bgthsp70c response to heat stress in haustoria formation and hyphal expansion stages.

10.
Nanomaterials (Basel) ; 12(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36234608

RESUMO

Amorphous InGaZnO (a-InGaZnO) is currently the most prominent oxide semiconductor complement to low-temperature polysilicon for thin-film transistor (TFT) applications in next-generation displays. However, balancing the transmission performance and low-temperature deposition is the primary obstacle in the application of a-InGaZnO TFTs in the field of ultra-high resolution optoelectronic display. Here, we report that a-InGaZnO:O TFT prepared at room temperature has high transport performance, manipulating oxygen vacancy (VO) defects through an oxygen-doped a-InGaZnO framework. The main electrical properties of a-InGaZnO:O TFTs included high field-effect mobility (µFE) of 28 cm2/V s, a threshold voltage (Vth) of 0.9 V, a subthreshold swing (SS) of 0.9 V/dec, and a current switching ratio (Ion/Ioff) of 107; significant improvements over a-InGaZnO TFTs without oxygen plasma. A possible reason for this is that appropriate oxygen plasma treatment and room temperature preparation technology jointly play a role in improving the electrical performance of a-InGaZnO TFTs, which could not only increase carrier concentration, but also reduce the channel-layer surface defects and interface trap density of a-InGaZnO TFTs. These provides a powerful way to synergistically boost the transport performance of oxide TFTs fabricated at room temperature.

11.
Crohns Colitis 360 ; 4(3): otac029, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36061451

RESUMO

Background: We compared real-world healthcare resource utilization (HRU), Crohn's disease (CD)-related complications, and time to systemic corticosteroid discontinuation between patients with CD treated with adalimumab versus vedolizumab as initial biologic. Methods: Biologic-naïve adults with CD and ≥2 claims between 05/20/2014 and 09/30/2019 for adalimumab or vedolizumab were identified in the IBM MarketScan research database. Patient characteristics were assessed during the 6-month baseline period before biologic initiation (index date). Adalimumab- and vedolizumab-treated patients were propensity score-matched 1:1 on demographics, disease characteristics, and comorbidities with ≥10% prevalence that differed significantly between groups. Categorical, continuous, and time-to-event outcomes between groups during the 12-month follow-up on/after index were compared with chi-square tests, Wilcoxon rank-sum tests, and Kaplan-Meier analyses, respectively. Results: Adalimumab- and vedolizumab-treated patients were matched (n = 461 per group) and baseline characteristics balanced. Significantly fewer adalimumab- versus vedolizumab-treated patients had a CD-related emergency room visit (12-month proportion: 14.5% vs 21.0%; log-rank P < 0.01) or inpatient admission (14.9% vs 20.2%; log-rank P < 0.05). Rates of CD-related surgeries were similar (9.3% vs 11.5%; log-rank P = 0.282). Among patients without internal/perianal abscess or fistula or intestinal stricture at baseline (N ADA = 360, N VDZ = 364), numerically but not significantly fewer adalimumab- versus vedolizumab-treated patients had CD-related complications at 12 months (18.3% vs 22.3%; P = 0.171). Among patients with corticosteroid use at index (N ADA = 143, N VDZ = 139), significantly more adalimumab- versus vedolizumab-treated patients discontinued corticosteroids (12-month proportion: 90.2% vs 76.3%; log-rank P < 0.001). Conclusions: Patients with CD treated with adalimumab as their first biologic experienced significantly lower CD-related HRU and were more likely to discontinue corticosteroids compared to vedolizumab-treated patients.

12.
Nanomaterials (Basel) ; 12(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36144939

RESUMO

The tin dioxide (SnO2) photocatalyst has a broad application prospect in the degradation of toxic organic pollutants. In this study, micron-sized spherical SnO2 and flower indium oxide (In2O3) structures were prepared by a simple hydrothermal method, and the In2O3/SnO2 composite samples were prepared by a "two-step method". Using Rhodamine B (RhB) as a model organic pollutant, the photocatalytic performance of the In2O3/SnO2 composites was studied. The photocurrent density of 1.0 wt.% In2O3/SnO2 was twice that of pure SnO2 or In2O3, and the degradation rate was as high as 97% after 240 min irradiation (87% after 120 min irradiation). The reaction rate was five times that of SnO2 and nine times that of In2O3. Combined with the trapping experiment, the transient photocurrent response, and the corresponding characterization of active substances, the possible degradation mechanism was that the addition of In2O3 inhibited the efficiency of electron-hole pair recombination, accelerated the electron transfer and enhanced the photocatalytic activity.

13.
Leukemia ; 36(8): 2108-2120, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35790816

RESUMO

Advanced systemic mastocytosis (AdvSM) is a rare myeloid neoplasm associated with poor overall survival (OS). This study (NCT04695431) compared clinical outcomes between patients with AdvSM treated with avapritinib in the Phase 1 EXPLORER (NCT0256198) and Phase 2 PATHFINDER (NCT03580655) trials (N = 176) and patients treated with best available therapy (BAT; N = 141). A multi-center, observational, retrospective chart review study was conducted at six study sites (four European, two American) to collect data from patients with AdvSM who received BAT; these data were pooled with data from EXPLORER and PATHFINDER. Comparisons between outcomes of OS, duration of treatment (DOT), and maximum reduction in serum tryptase were conducted between the treatment cohorts, with adjustment for key covariates. The results indicated that the avapritinib cohort had significantly better survival (adjusted hazard ratio (HR) (95% confidence interval (CI)): 0.48 (0.29, 0.79); p = 0.004) and significantly longer DOT (HR: 0.36 (0.26, 0.51); p < 0.001) compared to the BAT cohort. Additionally, the mean difference in percentage maximum reduction in serum tryptase levels was 60.3% greater in the avapritinib cohort (95% CI: -72.8, -47.9; p < 0.001). With no randomized controlled trials comparing avapritinib to BAT, these data offer crucial insights into the improved efficacy of avapritinib for the treatment of AdvSM.


Assuntos
Mastocitose Sistêmica , Humanos , Mastocitose Sistêmica/tratamento farmacológico , Pirazóis/uso terapêutico , Pirróis , Estudos Retrospectivos , Triazinas , Triptases/uso terapêutico
14.
Front Plant Sci ; 13: 864192, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651769

RESUMO

Effective strategies to reduce the occurrence of wheat powdery mildew include the use of resistant varieties and application of fungicides. However, most studies rarely focus on the quantitative value of fungicide reduction using resistant varieties. To explore how the fungicides performed on different resistant wheat varieties to powdery mildew, field experiments were conducted during wheat growing seasons in 2018/19 and 2019/20 to investigate the control efficacies of enostroburin⋅epoxiconazole 18% SC and triadimefon 20% EC to wheat powdery mildew on a highly resistant wheat variety ("Baofeng104") and a highly susceptible wheat variety ("Jingshuang16"). The analyses of variance on control efficacies showed that the control efficacies of enostroburin⋅epoxiconazole 18% SC to wheat powdery mildew were mostly significantly higher than triadimefon 20% EC under the same conditions (i.e., varieties, dosages). However, both fungicide and variety resistance made variabilities in the mildew disease index and played a significant role in mildew management. Particularly, the variety resistance made the greatest contribution in mildew-reducing, and the disease index could significantly be reduced on the highly resistant variety even in the absence of fungicide treatment. The control efficacies to mildew on the highly susceptible variety mainly depended on the high efficiency of fungicides whereas the highly resistant variety were mainly by virtue of variety resistance through the comparative analyses of linear regression models. Furthermore, the random-coefficient regression models and quantile models quantificationally expounded that the relationships between active ingredient dosage and disease index or control efficacy varied from the effects of variety, fungicide, and year, particular from variety. Thus, a dosage reference table of enostroburin⋅epoxiconazole 18% SC or triadimefon 20% EC for different resistant wheat varieties were provided; it would be helpful for users to formulate an appropriate dosage of fungicide on mildew management in the field and avoid overusing or superfluous application. Further study needs to consider the effects of fungicide reduction on wheat yields, only then the maximum-economic benefits on mildew management can be determined.

15.
Plant Dis ; 106(11): 2940-2947, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35365051

RESUMO

Long-distance dispersal of plant pathogens in the air can establish diseases in other areas and lead to an increased risk of large-scale epidemics. Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat in China. Hubei is an important overwintering region for Pst in China, and this overwintering region is a determinant of stripe rust severity in eastern China. In 2017, stripe rust disease caused a pandemic in the Hubei region and resulted in great yield losses of wheat. To explain the disease pandemic, a total of 595 single-lesion samples of stripe rust were collected in spring, including 204 in five provinces in 2017 and 391 in four provinces in 2018, and genotyped with 13 simple sequence repeat makers. The samples were classified into 12 subpopulations based on the locations and year of collection. Genetic diversity was determined for the collection and each subpopulation. Differentiation and gene flow were determined between subpopulations. STRUCTURE analyses and discriminant analysis of principal components were conducted, and the results were used to infer the relationships between subpopulations. Our study revealed a new route of Pst transmission from the Yunnan-Guizhou Plateau to the Hubei region. The Pst inoculum of northwestern Hubei came from Gansu in the northwest, whereas the inoculum in southern Hubei came from the Yunnan-Guizhou Plateau via upper airflow. After the initial inocula infected wheat plants and multiplied in northern and southern Hubei, urediniospores produced in these regions further spread together along the middle reach of Hanshui Valley and made exchanges there. The finding of the new transmission route of Pst is important for improving integrated stripe rust disease management, which should have a profound impact on the balance of agricultural ecology in China.


Assuntos
Basidiomycota , Doenças das Plantas , Doenças das Plantas/genética , China , Basidiomycota/genética , Triticum/genética
16.
Cell ; 185(3): 547-562.e22, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35051369

RESUMO

Hundreds of microbiota genes are associated with host biology/disease. Unraveling the causal contribution of a microbiota gene to host biology remains difficult because many are encoded by nonmodel gut commensals and not genetically targetable. A general approach to identify their gene transfer methodology and build their gene manipulation tools would enable mechanistic dissections of their impact on host physiology. We developed a pipeline that identifies the gene transfer methods for multiple nonmodel microbes spanning five phyla, and we demonstrated the utility of their genetic tools by modulating microbiome-derived short-chain fatty acids and bile acids in vitro and in the host. In a proof-of-principle study, by deleting a commensal gene for bile acid synthesis in a complex microbiome, we discovered an intriguing role of this gene in regulating colon inflammation. This technology will enable genetically engineering the nonmodel gut microbiome and facilitate mechanistic dissection of microbiota-host interactions.


Assuntos
Microbioma Gastrointestinal/genética , Genes Bacterianos , Animais , Ácidos e Sais Biliares/metabolismo , Sistemas CRISPR-Cas/genética , Clostridium/genética , Colite/induzido quimicamente , Colite/microbiologia , Colite/patologia , Sulfato de Dextrana , Resistência Microbiana a Medicamentos/genética , Feminino , Regulação Bacteriana da Expressão Gênica , Técnicas de Transferência de Genes , Vida Livre de Germes , Inflamação/patologia , Intestinos/patologia , Masculino , Metaboloma/genética , Metagenômica , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutagênese Insercional/genética , Mutação/genética , RNA Ribossômico 16S/genética , Transcrição Gênica
17.
Bioprocess Biosyst Eng ; 44(12): 2615-2625, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34477974

RESUMO

The novel MnCo2O4 (MCO/CF), CNTs-MnCo2O4 (CNTs-MCO/CF) and MnFe2O4-MnCo2O4 (MFO-MCO/CF) electrodes were prepared on carbon felt (CF) by simple hydrothermal and coating method as anodes for MFC. The modified anodes combine the electrocatalytic properties of transition metal oxides (TMOs), the high electrical conductivity of CNTs and the good biocompatibility of CF. These anodes play a synergistically role in the synthesis of structural, to realize high-efficiency electron transfer, low resistance and sufficient space for microbial colonization, while also ensuring high power density. The maximum power density of the composite electrodes CNTs-MCO/CF and MFO-MCO/CF were 4268 mW/m3 and 3660 mW/m3, respectively. The synergistic effect of multi-component effectively improves the performance of MFC. This work not only offers a good design and preparation concept for functional TMOs composite electrodes, but also provides an important guide for the fabrication of CNTs-doped MFC anodes.


Assuntos
Fontes de Energia Bioelétrica , Carbono/química , Cobalto/química , Eletrodos , Compostos de Manganês/química , Óxidos/química
18.
J Am Soc Mass Spectrom ; 32(9): 2425-2435, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34409840

RESUMO

Non-targeted analysis (NTA), including both suspect screening analysis (SSA) and unknown compound analysis, has gained increasing popularity in various fields for its capability in identifying new compounds of interests. Current major challenges for NTA SSA are that (1) tremendous effort and resources are needed for large-scale identification and confirmation of suspect chemicals and (2) suspect chemicals generally show low matching rates during identification and confirmation processes. To narrow the gap between these challenges and smooth implementation of NTA SSA methodology in the biomonitoring field, we present a thorough SSA workflow for the large-scale screen, identification, and confirmation of industrial chemicals that may pose adverse health effects in pregnant women and newborns. The workflow was established in a study of 30 paired maternal and umbilical cord serum samples collected at delivery in the San Francisco Bay area. By analyzing LC-HRMS and MS/MS data, together with the assistance of a combination of resources including online MS/MS spectra libraries, online in silico fragmentation tools, and the EPA CompTox Chemicals Dashboard, we confirmed the identities of 17 chemicals, among which monoethylhexyl phthalate, 4-nitrophenol, tridecanedioic acid, and octadecanedioic acid are especially interesting due to possible toxicities and their high-volume use in industrial manufacturing. Similar to other previous studies in the SSA field, the suspect compounds show relatively low MS/MS identification (16%) and standard confirmation (8%) rates. Therefore, we also investigated origins of false positive features and unidentifiable suspected features, as well as technical obstacles encountered during the confirmation process, which would promote a better understanding of the flaw of low confirmation rate and encourage gaining more effective tools for tackling this issue in NTA SSA.


Assuntos
Cromatografia Líquida/métodos , Bases de Dados de Compostos Químicos , Exposição Ambiental/análise , Espectrometria de Massas em Tandem/métodos , Feminino , Sangue Fetal/química , Humanos , Recém-Nascido , Exposição Materna , Compostos Orgânicos/sangue , Ácidos Ftálicos/sangue , Gravidez
19.
Environ Sci Technol ; 55(15): 10542-10557, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34260856

RESUMO

Recent technological advances in mass spectrometry have enabled us to screen biological samples for a very broad spectrum of chemical compounds allowing us to more comprehensively characterize the human exposome in critical periods of development. The goal of this study was three-fold: (1) to analyze 590 matched maternal and cord blood samples (total 295 pairs) using non-targeted analysis (NTA); (2) to examine the differences in chemical abundance between maternal and cord blood samples; and (3) to examine the associations between exogenous chemicals and endogenous metabolites. We analyzed all samples with high-resolution mass spectrometry using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF/MS) in both positive and negative electrospray ionization modes (ESI+ and ESI-) and in soft ionization (MS) and fragmentation (MS/MS) modes for prioritized features. We confirmed 19 unique compounds with analytical standards, we tentatively identified 73 compounds with MS/MS spectra matching, and we annotated 98 compounds using an annotation algorithm. We observed 103 significant associations in maternal and 128 in cord samples between compounds annotated as endogenous and compounds annotated as exogenous. An example of these relationships was an association between three poly and perfluoroalkyl substances (PFASs) and endogenous fatty acids in both the maternal and cord samples indicating potential interactions between PFASs and fatty acid regulating proteins.


Assuntos
Expossoma , Espectrometria de Massas em Tandem , Cromatografia Líquida , Feminino , Humanos , Gravidez , Espectrometria de Massas por Ionização por Electrospray
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