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1.
Front Public Health ; 12: 1333811, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605869

RESUMO

Background: In recent years, an increasing number of observational studies have reported the impact of air pollution on autoimmune diseases (ADs). However, no Mendelian randomization (MR) studies have been conducted to investigate the causal relationships. To enhance our understanding of causality, we examined the causal relationships between particulate matter (PM) and nitrogen oxides (NOx) and ADs. Methods: We utilized genome-wide association study (GWAS) data on PM and NOx from the UK Biobank in European and East Asian populations. We also extracted integrated GWAS data from the Finnish consortium and the Japanese Biobank for two-sample MR analysis. We employed inverse variance weighted (IVW) analysis to assess the causal relationship between PM and NOx exposure and ADs. Additionally, we conducted supplementary analyses using four methods, including IVW (fixed effects), weighted median, weighted mode, and simple mode, to further investigate this relationship. Results: In the European population, the results of MR analysis suggested a statistically significant association between PM2.5 and psoriasis only (OR = 3.86; 95% CI: 1.89-7.88; PIVW < 0.00625), while a potential association exists between PM2.5-10 and vitiligo (OR = 7.42; 95% CI: 1.02-53.94; PIVW < 0.05), as well as between PM2.5 and systemic lupus erythematosus (OR = 68.17; 95% CI: 2.17-2.1e+03; PIVW < 0.05). In East Asian populations, no causal relationship was found between air pollutants and the risk of systemic lupus erythematosus and rheumatoid arthritis (PIVW > 0.025). There was no pleiotropy in the results. Conclusion: Our results suggest a causal association between PM2.5 and psoriasis in European populations. With the help of air pollution prevention and control, the harmful progression of psoriasis may be slowed.


Assuntos
Poluição do Ar , Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Psoríase , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Doenças Autoimunes/etiologia , Doenças Autoimunes/genética , Poluição do Ar/efeitos adversos , Material Particulado/efeitos adversos , Psoríase/etiologia , Psoríase/genética
2.
J Cardiothorac Surg ; 19(1): 194, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594687

RESUMO

BACKGROUND: Primary cardiac angiosarcoma(PCA) has a low incidence rate and poor prognosis. Currently, no unified clinical treatment standards are available. CASE PRESENTATION: We report the case of a 48-year-old man presenting chest tightness, breathlessness, and dyspnea. Imaging and postoperative histopathologic studies confirmed PCA and that the tumor had invaded the entire right atrium. The patient developed progressive disease (PD) during postoperative radiotherapy. We used immunotherapy combined with targeted therapy based on the results of molecular profile and evaluation of tertiary lymphoid structures (TLSs) and programmed cell death-ligand 1 (PD-L1). After treatment, the metastatic lymph nodes of the patient were reduced to a certain extent, indicating that combination therapy was effective. CONCLUSION: To the best of our knowledge, this is the first report of radiotherapy combined with anti-PD-1 and tyrosine kinase inhibitors(TKI) for PCA. In addition, this is the first report on immunotherapy for PCA based on new evaluation methods, including TLSs, PD-L1, and genomic profile.


Assuntos
Hemangiossarcoma , Neoplasias Pulmonares , Estruturas Linfoides Terciárias , Masculino , Humanos , Pessoa de Meia-Idade , Antígeno B7-H1 , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/terapia , Neoplasias Pulmonares/patologia
3.
mSphere ; : e0006124, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564709

RESUMO

Mycobacterium tuberculosis (Mtb), the pathogenic bacterium that causes tuberculosis, has evolved sophisticated defense mechanisms to counteract the cytotoxicity of reactive oxygen species (ROS) generated within host macrophages during infection. The melH gene in Mtb and Mycobacterium marinum (Mm) plays a crucial role in defense mechanisms against ROS generated during infection. We demonstrate that melH encodes an epoxide hydrolase and contributes to ROS detoxification. Deletion of melH in Mm resulted in a mutant with increased sensitivity to oxidative stress, increased accumulation of aldehyde species, and decreased production of mycothiol and ergothioneine. This heightened vulnerability is attributed to the increased expression of whiB3, a universal stress sensor. The absence of melH also resulted in reduced intracellular levels of NAD+, NADH, and ATP. Bacterial growth was impaired, even in the absence of external stressors, and the impairment was carbon source dependent. Initial MelH substrate specificity studies demonstrate a preference for epoxides with a single aromatic substituent. Taken together, these results highlight the role of melH in mycobacterial bioenergetic metabolism and provide new insights into the complex interplay between redox homeostasis and generation of reactive aldehyde species in mycobacteria. IMPORTANCE: This study unveils the pivotal role played by the melH gene in Mycobacterium tuberculosis and in Mycobacterium marinum in combatting the detrimental impact of oxidative conditions during infection. This investigation revealed notable alterations in the level of cytokinin-associated aldehyde, para-hydroxybenzaldehyde, as well as the redox buffer ergothioneine, upon deletion of melH. Moreover, changes in crucial cofactors responsible for electron transfer highlighted melH's crucial function in maintaining a delicate equilibrium of redox and bioenergetic processes. MelH prefers epoxide small substrates with a phenyl substituted substrate. These findings collectively emphasize the potential of melH as an attractive target for the development of novel antitubercular therapies that sensitize mycobacteria to host stress, offering new avenues for combating tuberculosis.

5.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623654

RESUMO

BACKGROUND: Blood shortage is a global challenge, impacting elective surgeries with high bleeding risk. Predicting intraoperative blood use, optimizing resource allocation, and ensuring safe elective surgery are vital. This study targets identifying key bleeding risk factors in Aortic Valve Replacement (AVR) through machine learning. METHODS: Data from 702 AVR patients were split into 70% training and 30% test sets. Thirteen models predicted RBC transfusion. SHapley Additive exPlanations (SHAP) analyzed risk factors. RESULTS: Logistic Regression excelled, with Area Under Curve (AUC) 0.872 and 81.0% accuracy on the test set. Notably, female gender, Hemoglobin (HGB) < 131.91 g/L, Hematocrit (HCT) < 0.41L/L, weight < 59.49 kg, age > 54.47 year, Mean Corpuscular Hemoglobin (MCH) < 29.15 pg, Total Protein (TP) > 69.7 g/L, FIB > 2.61 g/L, height < 160 cm, and type of operation is Surgical Aortic Valve Replacement (SAVR) were significant RBC transfusion predictors. CONCLUSIONS: The study's model accurately forecasts AVR-related RBC transfusions. This informs presurgery blood preparations, reducing resource waste and aiding clinicians in optimizing patient care.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Humanos , Feminino , Valva Aórtica/cirurgia , Transfusão de Eritrócitos , Fatores de Risco , Aprendizado de Máquina , Estudos Retrospectivos
6.
J Colloid Interface Sci ; 666: 47-56, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38583209

RESUMO

Solar light-driven hydrogen peroxide (H2O2) production through the two-electron oxygen reduction reaction (ORR) from the earth-abundant O2 and water is a potential alternative to the energy-consuming anthraquinone oxidation process, although the activity of the common photocatalysts is still insufficient to satisfy the industrial demands. Poor accessibility of O2 to surface/interface and fast carrier recombination is the limiting-factor for catalytic systems. Herein, we develop a nanohybrid photocatalysts by introducing 1D conducting polymer of polypyrrole (PPy) nanotube on In4SnS8 to promote H2O2 evolution under visible light, obtaining up to 254.8 µM in 2 h, which is 2.4- and 13-fold larger than that of individual In4SnS8 and PPy. The detailed characterizations of hybrid structure, O2 adsorption behaviors, charge carrier dynamics over PPy/In4SnS8 in conjunction with computational calculations corroborate that the modification of PPy could enlarge the amount of O2 adsorption amount, expedite the cycle of O2 adsorption/desorption and accelerate the transportation of electrons from In4SnS8 to the interface, eventually speeding up H2O2 photoproduction via indirect 2e- ORR pathway. This work establishes a paradigm of regulating the interfacial microenvironment by polymer for boosting H2O2 photogeneration through high selectivity of ORR.

7.
Hum Cell ; 37(3): 593-606, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38538930

RESUMO

Environmental temperature and cellular mechanical force are the inherent factors that participate in various biological processes and regulate cancer progress, which have been hot topics worldwide. They occupy a dominant part in the cancer tissues through different approaches. However, extensive investigation regarding pathological mechanisms in the carcinogenic field. After research, we found cold stress via two means to manipulate tumors: neuroscience and mechanically sensitive ion channels (MICHs) such as TRP families to regulate the physiological and pathological activities. Excessive cold stimulation mediated neuroscience acting on every cancer stage through the hypothalamus-pituitary-adrenocorticoid (HPA) to reach the target organs. Comparatively speaking, mechanical force via Piezo of MICHs controls cancer development. The progression of cancer depends on the internal activation of proto-oncogenes and the external tumorigenic factors; the above two means eventually lead to genetic disorders at the molecular level. This review summarizes the interaction of bidirectional communication between them and the tumor. It covers the main processes from cytoplasm to nucleus related to metastasis cascade and tumor immune escape.


Assuntos
Neoplasias , Humanos , Estresse Mecânico , Neoplasias/genética , Neoplasias/patologia , Carcinogênese , Canais Iônicos/genética , Temperatura Baixa
8.
J Gastrointest Oncol ; 15(1): 96-111, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38482215

RESUMO

Background: Preoperative nutritional support studies for patients undergoing gastrointestinal (GI) surgery mostly focused on enteral nutrition (EN) or long-term (≥7 days) parenteral nutrition (PN). Some studies also found that preoperative short-term PN could improve the postoperative short-term nutritional status of tumor patients. But whether short-term PN support (1-6 days) before surgery can improve the prognosis of patients undergoing surgery for gastric cancer (GC) remains unclear. Therefore, we focused on assessing the effect of preoperative short-term PN on the outcomes of patients undergoing radical surgery for GC. Methods: A retrospective analysis of 1,155 patients who underwent radical gastrectomy for GC between July 2014 and February 2019 was conducted. According to whether patients received short-term (1-6 days) PN support before surgery, patients were divided into non-PN group and PN group. After 1:1 propensity score matching (PSM), two groups of patients with similar baseline clinical characteristics were obtained. The incidence of various complications and overall survival (OS) rate were compared between the two groups, and logistic regression analysis for complications, Cox regression analysis for OS, and subgroup analysis were performed. Results: Each group had 478 patients after PSM, and the clinical characteristics were balanced. There were no significant differences in overall postoperative complications (pre-PSM: P=0.495; post-PSM: P>0.99), postoperative length of stay (LOS; pre-PSM: P=0.092; post-PSM: P=0.460), or readmission rate within 30 days (pre-PSM: P=0.496; post-PSM: P=0.793) between the two groups before and after PSM. The OS of PN group before matching was lower than that of non-PN group (P=0.023), but this difference was not significant after matching (P=0.950), but the PN group's hospitalization expenses were substantially greater than those of the control group (post-PSM: P<0.001). Preoperative short-term PN support was not an independent factor in the incidence of postoperative complications (P>0.99) and OS (P=0.949). Subgroup analyses failed to identify those patients who might benefit from preoperative short-term PN support. Conclusions: Preoperative short-term PN support may have no significant benefit on short-term postoperative complications or the long-term OS of patients with GC but increase hospitalization costs. It thus should not be the first choice of treatment for these patients.

9.
ChemSusChem ; : e202400210, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38511253

RESUMO

The electrode interface determines the performance of an electrochemical energy storage system. Using traditional electrolyte organic additives and high-concentration electrolyte emerging recently are two generally strategies for improving the electrode interface. Here, a hybrid-salt electrolyte strategy is proposed for constructing the stable electrode interface. Through the solubilization effect of phosphate ester on LiNO3, a hybrid-salts-based non-flammable phosphate ester electrolyte system (HSPE) with LiPF6 and LiNO3 as Li salts has been developed. By the strong interaction between NO3- and Li+, the Li+ solvation sheath and solvent behaviors have been modulated, thus the undesirable effects of phosphate ester are eliminated and a robust SEI is formed. Experimental results and theoretical calculations illustrate that NO3- as a kind of strongly coordinating anion is able to reduce the number of TEP molecules and lower the reduction reactivity of TEP. The reconfigured Li+ solvation structure allows the formation of an inorganic-rich SEI on the electrode surface. As a result, in the designed HSPE, the average coulombic efficiency of lithium plating/stripping is increased to 99.12%. This work explored a new approach to construct the electrode interface and addressing the poor interface performance issue of phosphate esters.

10.
J Sci Food Agric ; 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38308594

RESUMO

BACKGROUND: The increasing attention toward frozen soy-based foods has sparked interest. Variations exist in the quality and structure of soymilk gels induced by different salt ions, leading to diverse changes post-freezing. This study compared and analyzed the effects of calcium chloride (CC), magnesium chloride (MC) and calcium sulfate (CS) on the quality characteristics and protein structure changes of soymilk gels (CC-S, MC-S and CS-S) before and after freezing, and clarified the mechanisms of freezing on soymilk gel. RESULTS: The formation rate of soymilk gel is influenced by the type of salt ions. In comparison to CS and MC, soymilk gel induced by CC exhibited the fastest formation rate, highest gel hardness, lowest moisture content, and smaller gel pores. However, freezing treatment deteriorated the quality of soymilk gel induced by different salt ions, leading to a decline in textural properties (hardness and chewiness). Among these, the textual state of CC-induced soymilk gel remained optimal, exhibiting the least apparent damage and minimal cooking loss. Freezing treatments prompt a transition of soymilk gel secondary structure from ß-turns to ß-sheets, disrupting the protein's tertiary structure. Furthermore, freezing treatments also fostered the crosslinking between soymilk gel protein, increasing the content of disulfide bonds. CONCLUSION: The quality of frozen soymilk gel is influenced by the rate of gel formation induced by salt ions. After freezing, soymilk gel with faster gelation rates exhibited a greater tendency for the transformation of protein-water interactions into protein-protein interactions. They showed a higher degree of disulfide bond formation, resulting in a more tightly knit and firm frozen gel network structure with denser and more uniformly distributed pores. © 2024 Society of Chemical Industry.

12.
Inorg Chem ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346933

RESUMO

Zintl compounds have continuously received significant attention, primarily due to their structural characteristics that align with the properties of the electron crystal and phonon glass. In this study, the crystal structure and thermoelectric properties of the quaternary Zintl chalcogenide BaScCuTe3 are investigated. The band structure calculations for BaScCuTe3 reveal a slight energy split of 0.08 eV between the second valence band and the valence band maximum, suggesting the presence of multiband-transport behaviors. Substitution of rare earth Gd for Sc is conducted, which significantly increases the hole concentration from 4.1 × 1019 cm-3 to 8.2 × 1019 cm-3 at room temperature. Meanwhile, the Seebeck coefficient increases because of the participation of the second valence band. A maximum power factor of 6.56 µW/cm·K2 at 773 K is obtained, which is 72% higher than that of the pristine sample. Moreover, the lattice thermal conductivity decreases from 0.57 W/m·K for BaScCuTe3 to 0.48 W/m·K for BaSc0.97Gd0.03CuTe3 at 773 K, owing to the introduction of point-defect scattering. As a result, there is a noteworthy improvement in the thermoelectric figure of merit zT, increasing from 0.44 for the undoped sample to 0.85 for BaSc0.98Gd0.02CuTe3. Considering these findings, BaScCuTe3 exhibits great potential and holds promise for further investigation in the field of thermoelectric materials.

13.
Curr Med Sci ; 44(1): 121-133, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38393525

RESUMO

OBJECTIVE: Human adenovirus (HAdV) infection is common and can develop to serious conditions with high mortality, yet the mechanism of HAdV infection remains unclear. In the present study, the serum metabolite profiles of HAdV-7-infected patients with pneumonia or upper respiratory tract infection (URTI) were explored. METHODS: In total, 35 patients were enrolled in the study following an outbreak of HAdV-7 in the army, of whom 14 had pneumonia and 21 had URTI. Blood samples were collected at the acute stage and at the recovery stage and were analyzed by untargeted metabolomics. RESULTS: Over 90% of the differential metabolites identified between the pneumonia patients and URTI patients were lipids and lipid-like molecules, including glycerophospholipids, fatty acyls, and sphingolipids. The metabolic pathways that were significantly enriched were primarily the lipid metabolism pathways, including sphingolipid metabolism, glycerophospholipid metabolism, and linoleic acid metabolism. The sphingolipid metabolism was identified as a significantly differential pathway between the pneumonia patients and URTI patients and between the acute and recovery stages for the pneumonia patients, but not between the acute and recovery stages for the URTI patients. Ceramide and lactosylceramide, involved in sphingolipid metabolism, were significantly higher in the pneumonia patients than in the URTI patients with good discrimination abilities [area under curve (AUC) 0.742 and 0.716, respectively; combination AUC 0.801]. CONCLUSION: Our results suggested that HAdV modulated lipid metabolism for both the patients with URTI and pneumonia, especially the sphingolipid metabolism involving ceramide and lactosylceramide, which might thus be a potential intervention target in the treatment of HAdV infection.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Antígenos CD , Pneumonia , Infecções Respiratórias , Humanos , Adenovírus Humanos/genética , Lactosilceramidas , Infecções Respiratórias/epidemiologia , Pneumonia/complicações , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/metabolismo
14.
CNS Neurosci Ther ; 30(2): e14536, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38375982

RESUMO

BACKGROUND: Depression is a prevalent psychiatric disorder with high long-term morbidities, recurrences, and mortalities. Despite extensive research efforts spanning decades, the cellular and molecular mechanisms of depression remain largely unknown. What's more, about one third of patients do not have effective anti-depressant therapies, so there is an urgent need to uncover more mechanisms to guide the development of novel therapeutic strategies. Adenosine triphosphate (ATP) plays an important role in maintaining ion gradients essential for neuronal activities, as well as in the transport and release of neurotransmitters. Additionally, ATP could also participate in signaling pathways following the activation of postsynaptic receptors. By searching the website PubMed for articles about "ATP and depression" especially focusing on the role of extracellular ATP (eATP) in depression in the last 5 years, we found that numerous studies have implied that the insufficient ATP release from astrocytes could lead to depression and exogenous supply of eATP or endogenously stimulating the release of ATP from astrocytes could alleviate depression, highlighting the potential therapeutic role of eATP in alleviating depression. AIM: Currently, there are few reviews discussing the relationship between eATP and depression. Therefore, the aim of our review is to conclude the role of eATP in depression, especially focusing on the evidence and mechanisms of eATP in alleviating depression. CONCLUSION: We will provide insights into the prospects of leveraging eATP as a novel avenue for the treatment of depression.


Assuntos
Trifosfato de Adenosina , Depressão , Humanos , Trifosfato de Adenosina/metabolismo , Depressão/tratamento farmacológico , Astrócitos/metabolismo
15.
Clin Lab ; 70(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38213226

RESUMO

BACKGROUND: Ethylenediaminetetraacetic acid-dependent pseudothrombocytopenia (EDTA-PTCP) is a rare phenomenon characterized by pseudo low platelet counts when using EDTA as anticoagulant and can result in false decision making of platelet transfusion. METHODS: An application for platelet transfusion from a patient who planned to undergo spinal surgery was received by the Department of Transfusion service. The preoperative laboratory test results showed thrombocytopenia (platelet counts: 27 x 109/L). The surgeon planned to transfuse platelets before the operation to avoid bleeding in operation due to thrombocytopenia. However, the lab technologist found that there was aggregation of platelets under the microscope. Samples used with sodium citrate and heparin as anticoagulants were rechecked. RESULTS: The platelet count of the patient was normal in sodium citrate and heparin anticoagulant tubes. The patient had no history and clinical symptoms of thrombocytopenia. Therefore, the doctor canceled the platelet order. We also reviewed the relevant literature of EDTA-PTCP. CONCLUSIONS: EDTA-PTCP is rare and may result of a wrong decision of platelet transfusion. Correct understanding and treatment of this situation can avoid unnecessary platelet transfusion.


Assuntos
Ácido Edético , Transfusão de Plaquetas , Trombocitopenia , Humanos , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Tomada de Decisão Clínica , Ácido Edético/efeitos adversos , Heparina/uso terapêutico , Citrato de Sódio/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Trombocitopenia/terapia
16.
Neuroscience ; 540: 38-47, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38242280

RESUMO

Secretory clusterin (sCLU) plays an important role in the research progress of nervous system diseases. However, the physiological function of sCLU in Parkinson's disease (PD) are unclear. The purpose of this study was to examine the effects of sCLU-mediated autophagy on cell survival and apoptosis inhibition in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. We found that MPTP administration induced prolonged pole-climbing time, shortened traction time and rotarod time, significantly decreased TH protein expression in the SN tissue of mice. In contrast, sCLU -treated mice took less time to climb the pole and had an extended traction time and rotating rod time. Meanwhile, sCLU intervention induced increased expression of the TH protein in the SN of mice. These results indicated that sCLU intervention could reduce the loss of dopamine neurons in the SN area and alleviate dyskinesia in mice. Furthermore, MPTP led to suppressed viability, enhanced apoptosis, an increased Bax/Bcl-2 ratio, and cleaved caspase-3 in the SN of mice, and these effects were abrogated by sCLU intervention. In addition, MPTP increased the levels of P62 protein, decreased Beclin1 protein, decreased the ratio of LC3B-II/LC3B-I, and decreased the numbers of autophagosomes and autophagolysosomes in the SN tissues of mice. These effects were also abrogated by sCLU intervention. Activation of PI3K/AKT/mTOR signaling with MPTP inhibited autophagy in the SN of MPTP mice; however, sCLU treatment activated autophagy in MPTP-induced PD mice by inhibiting PI3K/AKT/mTOR signaling. These data indicated that sCLU treatment had a neuroprotective effect in an MPTP-induced model of PD.


Assuntos
Fármacos Neuroprotetores , Doença de Parkinson , Animais , Camundongos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Apoptose , Autofagia , Clusterina/metabolismo , Clusterina/farmacologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/metabolismo , Doença de Parkinson/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
17.
bioRxiv ; 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-37873194

RESUMO

Mycobacterium tuberculosis ( Mtb ), the pathogenic bacterium that causes tuberculosis, has evolved sophisticated defense mechanisms to counteract the cytotoxicity of reactive oxygen species (ROS) generated within host macrophages during infection. The melH gene in Mtb and Mycobacterium marinum ( Mm ) plays a crucial role in defense mechanisms against ROS generated during infection. We demonstrate that melH encodes an epoxide hydrolase and contributes to ROS detoxification. Deletion of melH in Mm resulted in a mutant with increased sensitivity to oxidative stress, increased accumulation of aldehyde species, and decreased production of mycothiol and ergothioneine. This heightened vulnerability is attributed to the increased expression of whiB3 , a universal stress sensor. The absence of melH also resulted in reduced intracellular levels of NAD + , NADH, and ATP. Bacterial growth was impaired, even in the absence of external stressors, and the impairment was carbon-source-dependent. Initial MelH substrate specificity studies demonstrate a preference for epoxides with a single aromatic substituent. Taken together, these results highlight the role of melH in mycobacterial bioenergetic metabolism and provide new insights into the complex interplay between redox homeostasis and generation of reactive aldehyde species in mycobacteria. Importance: This study unveils the pivotal role played by the melH gene in Mycobacterium tuberculosis and Mycobacterium marinum in combatting the detrimental impact of oxidative conditions during infection. This investigation revealed notable alterations in the level of cytokinin-associated aldehyde, para -hydroxybenzaldehyde, as well as the redox buffer ergothioneine, upon deletion of melH . Moreover, changes in crucial cofactors responsible for electron transfer highlighted melH 's crucial function in maintaining a delicate equilibrium of redox and bioenergetic processes. MelH prefers epoxide small substrates with a phenyl substituted substrate. These findings collectively emphasize the potential of melH as an attractive target for the development of novel antitubercular therapies that sensitize mycobacteria to host stress, offering new avenues for combating tuberculosis.

18.
Nanoscale ; 16(2): 941, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38059724

RESUMO

Correction for 'Elaborating the interplay between the detecting unit and emitting unit in infrared quantum dot up-conversion photodetectors' by Qiulei Xu et al., Nanoscale, 2023, 15, 8197-8203, https://doi.org/10.1039/D3NR01237A.

19.
Analyst ; 149(2): 386-394, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38050732

RESUMO

The presence of sulfamethoxazole (SMX) in natural waters has become a significant concern recently because of its detrimental effects on human health and the ecological environment. To address this issue, it is of utmost urgency to develop a reliable method that can determine SMX at ultra-low levels. In our research, we utilized PVP-induced shape control of a hydrothermal synthesis method to fabricate layer-like structured VS2, and employed it as an electrode modification material to prepare an electrochemical sensor for the sensitive determination of SMX. Thus, our prepared VS2 electrodes exhibited a linear range of 0.06-10.0 µM and a limit of detection (LOD) as low as 47.0 nM (S/N = 3) towards SMX detection. Additionally, the electrochemical sensor presented good agreement with the HPLC method, and afforded perfect recovery results (97.4-106.8%) in the practical analysis. The results validated the detection accuracy of VS2 electrodes, and demonstrated their successful applicability toward the sensitive determination of SMX in natural waters. In conclusion, this research provides a promising approach for the development of electrochemical sensors based on VS2 composite materials.


Assuntos
Antibacterianos , Compostos de Vanádio , Humanos , Sulfametoxazol , Técnicas Eletroquímicas/métodos , Eletrodos , Limite de Detecção
20.
J Exp Bot ; 75(5): 1580-1600, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38035729

RESUMO

Spikelet degeneration in rice (Oryza sativa L.) is a serious physiological defect, and can be regulated by soil moisture status and phytohormones. This study investigated the possibility that brassinosteroids (BRs) in collaboration with abscisic acid (ABA) are involved in mediating the effect of soil drying during meiosis on spikelet degeneration in rice. Three rice cultivars were field grown and three irrigation regimes including well watered (WW), moderate soil drying (MD), and severe soil drying (SD) were imposed during meiosis. MD significantly decreased spikelet degeneration in comparison with WW, due mainly to the alleviation in oxidative damage via enhancing ascorbate-glutathione (AsA-GSH) cycle activity in young panicles, and SD exhibited the opposite effects. Enhanced AsA-GSH cycle strength, decreased oxidative stress, and spikelet degeneration rate were closely associated with the synergistically elevated BR and ABA levels in young panicles in MD. In contrast, low BR and excessive ABA levels led to an increase in spikelet degeneration in SD. The three cultivars exhibited the same tendencies. The intrinsic link among AsA-GSH cycle, oxidative stress, spikelet degeneration rate, and BR and ABA levels was further verified by using transgenic rice lines and chemical regulators. BRs or ABA play a unique role in regulating spikelet degeneration. Synergistically increased BR and ABA levels in MD could work together to strengthen AsA-GSH cycle activity, leading to a reduction in oxidative damage and spikelet degeneration. On the other hand, a severe imbalance between low BR and excessive ABA levels may have contributed to the opposite effects in SD.


Assuntos
Ácido Abscísico , Oryza , Brassinosteroides , Oryza/fisiologia , Solo , Meiose , Água
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