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1.
J Integr Plant Biol ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411333

RESUMO

Halorhodospira (Hlr.) halochloris is a triply extremophilic phototrophic purple sulfur bacterium, as it is thermophilic, alkaliphilic, and extremely halophilic. The light-harvesting-reaction center (LH1-RC) core complex of this bacterium displays an LH1-Qy transition at 1,016 nm, which is the lowest-energy wavelength absorption among all known phototrophs. Here we report the cryo-EM structure of the LH1-RC at 2.42 Å resolution. The LH1 complex forms a tricyclic ring structure composed of 16 αßγ-polypeptides and one αß-heterodimer around the RC. From the cryo-EM density map, two previously unrecognized integral membrane proteins, referred to as protein G and protein Q, were identified. Both of these proteins are single transmembrane-spanning helices located between the LH1 ring and the RC L-subunit and are absent from the LH1-RC complexes of all other purple bacteria of which the structures have been determined so far. Besides bacteriochlorophyll b molecules (B1020) located on the periplasmic side of the Hlr. halochloris membrane, there are also two arrays of bacteriochlorophyll b molecules (B800 and B820) located on the cytoplasmic side. Only a single copy of a carotenoid (lycopene) was resolved in the Hlr. halochloris LH1-α3ß3 and this was positioned within the complex. The potential quinone channel should be the space between the LH1-α3ß3 that accommodates the single lycopene but does not contain a γ-polypeptide, B800 and B820. Our results provide a structural explanation for the unusual Qy red shift and carotenoid absorption in the Hlr. halochloris spectrum and reveal new insights into photosynthetic mechanisms employed by a species that thrives under the harshest conditions of any phototrophic microorganism known.

2.
Dalton Trans ; 53(8): 3685-3689, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38293865

RESUMO

Metal-organic frameworks (MOFs) can be used as electrocatalysts for the CO2 reduction reaction (CO2RR) because of their well-dispersed metal centers. Silver is a common electrocatalyst for reduction of CO2 to CO. In this study, two Ag-MOFs with different structures of [Ag8O2(TIPE)6](NO3)4 (Ag-MOF1) and [Ag(TIPE)0.5CF3SO3] (Ag-MOF2) [TIPE = 1,1,2,2-tetrakis(4-(imidazol-1-yl)phenyl)ethene] were synthesized and used for CO2 electroreduction. The results show that Ag-MOF2 is superior to Ag-MOF1 and exhibits high CO faradaic efficiency (FE) of 92.21% with partial current density of 29.51 mA cm-2 at -0.98 V versus reversible hydrogen electrode (RHE). The FECO is higher than 80% in the potential range of -0.78 to -1.18 V. The difference may be caused by different framework structures leading to different electrochemical active surface areas and charge transfer kinetics. This study provides a new strategy for designing and constructing CO2 electroreduction catalysts and provides potential ways for solving environmental and energy problems caused by excessive CO2 emission.

3.
Biochem Genet ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049684

RESUMO

Bladder cancer (BCa), which usually occurs in bladder epithelial cells and is the fifth most common type of cancer in the world. he recurrence rate within 5 years after surgery is 0.8-45% of patients with early bladder cancer. Therefore, finding appropriate drug therapy for patients with bladder cancer can provide a reference for clinical treatment and play an important role in improving the prognosis of patients. In this study, CCK8 assay result showed that the inhibition of bladder cancer cell activity by Curdione and GEM increased with time and dose. Subsequently, CCK8, clone formation assay and Transwell result showed Curdione enhances GEM inhibition of bladder cancer cell activity, clonal formation and migration, these combine therapeutic schedule also could inhibited growth of in vivo xenograft tumors. The comprehensive database showed that CA2 is a potential target genes of Curdione, and Knockdown CA2 enhances GEM induced inhibition of cell proliferation and migration. Based on these advantages, Curdione may be a new type of action drug or adjunct for the treatment of bladder cancer.

4.
Front Cardiovasc Med ; 10: 1275713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928759

RESUMO

Background: This study was to probe into the relationship between the neutrophil-to-lymphocyte ratio (NLR) and both in-hospital and long-term heart failure risk in patients with acute myocardial infarction (AMI). Methods: 990 patients with AMI, including 386 with non-ST-segment elevation myocardial infarction (NSTEMI) and 604 with segment elevation myocardial infarction (STEMI) were recruited between January 2019 and March 2022. The in-hospital acute heart failure (AHF) and arrhythmia events were recorded. Results: The NLR was significantly greater in the AHF group in STEMI and NSTEMI patients, with a higher frequency of arrhythmia in comparison to the non-AHF group. A high NLR was related to a high level of myocardial injury markers, accompanied with more AHF and arrhythmia events. Multivariate logistic regression analyses revealed that high NLR is independently linked with increased in-hospital AHF and arrhythmia risk. Receiver operating characteristic curve analyses revealed that the prognostic value of NLR for in-hospital AHF was 0.704 in STEMI patients and 0.766 in NSTEMI patients. However, during a median follow-up of 28 months with 32 heart failure patients, there was no significant difference between the low NLR group (n = 18) and the high NLR group (n = 14). Further analysis showed that the two groups did not significantly differ in the occurrence of heart failure within 12 months of discharge. Conclusion: Our results indicate that NLR is an independent risk factor of in-hospital AHF in AMI patients. However, NLR has no value in predicting long-term heart failure.

5.
Cell Death Dis ; 14(9): 598, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679327

RESUMO

Lactate leads to the imbalance of mitochondria homeostasis, which then promotes vascular calcification. PARP1 can upregulate osteogenic genes and accelerate vascular calcification. However, the relationship among lactate, PARP1, and mitochondrial homeostasis is unclear. The present study aimed to explore the new molecular mechanism of lactate to promote VSMC calcification by evaluating PARP1 as a breakthrough molecule. A coculture model of VECs and VSMCs was established, and the model revealed that the glycolysis ability and lactate production of VECs were significantly enhanced after incubation in DOM. Osteogenic marker expression, calcium deposition, and apoptosis in VSMCs were decreased after lactate dehydrogenase A knockdown in VECs. Mechanistically, exogenous lactate increased the overall level of PARP and PARylation in VSMCs. PARP1 knockdown inhibited Drp1-mediated mitochondrial fission and partially restored PINK1/Parkin-mediated mitophagy, thereby reducing mitochondrial oxidative stress. Moreover, lactate induced the translocation of PARP1 from the nucleus to the mitochondria, which then combined with POLG and inhibited POLG-mediated mitochondrial DNA synthesis. This process led to the downregulation of mitochondria-encoded genes, disturbance of mitochondrial respiration, and inhibition of oxidative phosphorylation. The knockdown of PARP1 could partially reverse the damage of mitochondrial gene expression and function caused by lactate. Furthermore, UCP2 was upregulated by the PARP1/POLG signal, and UCP2 knockdown inhibited Drp1-mediated mitochondrial fission and partially recovered PINK1/Parkin-mediated mitophagy. Finally, UCP2 knockdown in VSMCs alleviated DOM-caused VSMC calcification in the coculture model. The study results thus suggest that upregulated PARP1 is involved in the mechanism through which lactate accelerates VSMC calcification partly via POLG/UCP2-caused unbalanced mitochondrial homeostasis.


Assuntos
Ácido Láctico , Calcificação Vascular , Humanos , Músculo Liso Vascular , Homeostase , Calcificação Vascular/genética , Mitocôndrias , Transdução de Sinais , DNA Mitocondrial , Proteínas Quinases , DNA Polimerase gama , Poli(ADP-Ribose) Polimerase-1/genética , Proteína Desacopladora 2
6.
EMBO J ; 42(17): e113415, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37485728

RESUMO

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones ß-estradiol 17-(ß-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Estradiol , Humanos , Transportadores de Cassetes de Ligação de ATP/genética , Estradiol/farmacologia , Estradiol/metabolismo , Mutagênese Sítio-Dirigida
7.
Sci Bull (Beijing) ; 68(14): 1540-1555, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37422372

RESUMO

Gut microbiota dysbiosis is associated with the development of rheumatoid arthritis (RA). Sinomenine (SIN) is an effective immunosuppressive and anti-inflammatory drug used for treating RA, but how SIN regulates gut microbiota to alleviate RA remains underexplored. To identify the critical gut microbial species and microbial metabolites associated with the RA-protective effects of SIN, the microbiota-dependent anti-RA effects of SIN were assessed by 16S rRNA gene sequencing, antibiotic treatment, and fecal microbiota transplantation. Metabolomics analysis, transcriptional analysis, and targeted bacteria/metabolites gavage were conducted to explore how SIN regulates gut microbiota to reduce the severity of RA. SIN could restore intestinal microbial balance by mainly modulating the abundance of Lactobacillus, and significantly relieve collagen-induced arthritis (CIA) symptoms in a gut microbiota-dependent manner. SIN significantly elevated microbial tryptophan metabolites indole-3-acrylic acid (IA), indole-3-propionic acid (IPA), and indole-3-acetic acid (IAA). Tryptophan metabolites supplementation could activate aryl hydrocarbon receptor (AhR) and regulate Th17/Treg balance in CIA rats. Intriguingly, SIN relieved the arthritis symptoms involving the enrichment of two beneficial anti-CIA Lactobacillus species, L. paracasei and L. casei by mono-colonization. The promising therapeutic function of SIN was mostly attributed to the activation of AhR by explicitly targeting the Lactobacillus and microbial tryptophan metabolites. The intestinal bacterium L. paracasei and L. casei may be used to reduce the severity of CIA.

8.
J Biol Chem ; 299(8): 105057, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37468106

RESUMO

In wild-type phototrophic organisms, carotenoids (Crts) are primarily packed into specific pigment-protein complexes along with (Bacterio)chlorophylls and play important roles in the photosynthesis. Diphenylamine (DPA) inhibits carotenogenesis but not phototrophic growth of anoxygenic phototrophs and eliminates virtually all Crts from photocomplexes. To investigate the effect of Crts on assembly of the reaction center-light-harvesting (RC-LH) complex from the filamentous anoxygenic phototroph Roseiflexus (Rfl.) castenholzii, we generated carotenoidless (Crt-less) RC-LH complexes by growing cells in the presence of DPA. Here, we present cryo-EM structures of the Rfl. castenholzii native and Crt-less RC-LH complexes with resolutions of 2.86 Å and 2.85 Å, respectively. From the high-quality map obtained, several important but previously unresolved details in the Rfl. castenholzii RC-LH structure were determined unambiguously including the assignment and likely function of three small polypeptides, and the content and spatial arrangement of Crts with bacteriochlorophyll molecules. The overall structures of Crt-containing and Crt-less complexes are similar. However, structural comparisons showed that only five Crts remain in complexes from DPA-treated cells and that the subunit X (TMx) flanked on the N-terminal helix of the Cyt-subunit is missing. Based on these results, the function of Crts in the assembly of the Rfl. castenholzii RC-LH complex and the molecular mechanism of quinone exchange is discussed. These structural details provide a fresh look at the photosynthetic apparatus of an evolutionary ancient phototroph as well as new insights into the importance of Crts for proper assembly and functioning of the RC-LH complex.


Assuntos
Proteínas de Bactérias , Chloroflexi , Fotossíntese , Proteínas de Bactérias/metabolismo , Carotenoides/metabolismo , Chloroflexi/metabolismo , Complexos de Proteínas Captadores de Luz/química
9.
Cell Signal ; 109: 110740, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37268163

RESUMO

Endothelial injury and dysfunction contributes to atherosclerosis. LINC00346 plays a key role in vascular endothelial cell injury, however, the specific mechanism remains unclear. This study intends to further explore the relationship between LINC00346 and vascular endothelial injury. Circulating LINC00346 was significantly elevated in patients with coronary artery disease and had high diagnostic value for coronary artery disease. In cell experiments, we found that LINC00346 expression was significantly increased in the oxidized low-density lipoprotein (ox-LDL) intervention group, and LINC00346 knockdown delayed ox-LDL induced human umbilical vein endothelial cell (HUVEC) endothelial-to-mesenchymal transition. In addition, knockdown of LINC00346 mitigated ox-LDL-induced NOD-like receptor protein 1 (NLRP1)-mediated inflammasome formation and pyroptosis, but had no significant effect on NLRP3. By observing the number of autophagosome and detecting intracellular autophagic flux, we found that LINC00346 knockdown inhibited the ox-LDL-induced increase in intracellular autophagy level. Dual-luciferase reporter assay, RNA immunoprecipitation assay, and RNA-pull down assay were performed to confirm the inter-molecular interaction. LINC00346 acted as microRNA-637 sponge to up-regulate the expression of NLRP1. Up-regulation of microRNA-637 alleviated NLRP1-mediated pyroptosis in HUVEC and reduced intracellular autophagosome and autolysosome formation. Finally, we explored whether pyropotosis and autophagy interact with each other. We found that inhibition of intracellular autophagy could alleviate NLRP1-mediated pyroptosis. In conclusion, LINC00346 inhibited the activation of NLRP1-mediated pyroptosis and autophagy via binding to microRNA-637, therefore mitigating vascular endothelial injury.


Assuntos
Doença da Artéria Coronariana , MicroRNAs , Lesões do Sistema Vascular , Humanos , MicroRNAs/metabolismo , Piroptose , Endotélio Vascular/metabolismo , Proteínas NLR/metabolismo , Doença da Artéria Coronariana/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Autofagia , Lesões do Sistema Vascular/metabolismo , Lipoproteínas LDL/farmacologia , Lipoproteínas LDL/metabolismo , Apoptose
10.
Front Cardiovasc Med ; 10: 1158507, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37260943

RESUMO

Background and aims: The roles of sodium-glucose cotransporter 2 inhibitor (SGLT2i) in acute heart failure (AHF) risk after acute myocardial infarction (AMI) remain unclear. In this study, we explored the correlation between SGLT2i administration and short-term in-hospital AHF risk in AMI patients. Methods: This single-center, retrospective, and observational study included 990 AMI patients comprising 386 non-ST-segment elevation myocardial infarction (NSTEMI) and 604 segment elevation myocardial infarction (STEMI) patients enrolled from January 2019 to March 2022. Demographic information, clinical characteristics, medical treatment, and laboratory examination results during hospitalization were extracted from an electronic medical record system. The primary outcome was defined as all-cause AHF during hospitalization. Results: In NSTEMI patients, a significantly lower proportion received SGLT2i treatment in the AHF group compared with the non-AHF group. During hospitalization, SGLT2i significantly reduced brain natriuretic peptide levels both in STEMI and NSTEMI patients. Multivariate logistic regression and stratification analyses suggested that SGLT2i is associated with reduced in-hospital AHF risk, and has a strong protective effect against AHF in NSTEMI patients with hypertension. Furthermore, SGLT2i significantly reduced the risk of in-hospital AHF for both patients with diabetes and non-diabetes. Conclusions: SGLT2i can reduce the risk of AHF in AMI patients during hospitalization.

11.
BMC Bioinformatics ; 24(1): 89, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894886

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) has a high incidence and mortality worldwide, which seriously threatens people's physical and mental health. Coagulation is closely related to the occurrence and development of HCC. Whether coagulation-related genes (CRGs) can be used as prognostic markers for HCC remains to be investigated. METHODS: Firstly, we identified differentially expressed coagulation-related genes of HCC and control samples in the datasets GSE54236, GSE102079, TCGA-LIHC, and Genecards database. Then, univariate Cox regression analysis, LASSO regression analysis, and multivariate Cox regression analysis were used to determine the key CRGs and establish the coagulation-related risk score (CRRS) prognostic model in the TCGA-LIHC dataset. The predictive capability of the CRRS model was evaluated by Kaplan-Meier survival analysis and ROC analysis. External validation was performed in the ICGC-LIRI-JP dataset. Besides, combining risk score and age, gender, grade, and stage, a nomogram was constructed to quantify the survival probability. We further analyzed the correlation between risk score and functional enrichment, pathway, and tumor immune microenvironment. RESULTS: We identified 5 key CRGs (FLVCR1, CENPE, LCAT, CYP2C9, and NQO1) and constructed the CRRS prognostic model. The overall survival (OS) of the high-risk group was shorter than that of the low-risk group. The AUC values for 1 -, 3 -, and 5-year OS in the TCGA dataset were 0.769, 0.691, and 0.674, respectively. The Cox analysis showed that CRRS was an independent prognostic factor for HCC. A nomogram established with risk score, age, gender, grade, and stage, has a better prognostic value for HCC patients. In the high-risk group, CD4+T cells memory resting, NK cells activated, and B cells naive were significantly lower. The expression levels of immune checkpoint genes in the high-risk group were generally higher than that in the low-risk group. CONCLUSIONS: The CRRS model has reliable predictive value for the prognosis of HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Prognóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Nomogramas , Fatores de Risco , Microambiente Tumoral
12.
Front Neurol ; 13: 1014346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36545400

RESUMO

Background: The incidence, prevalence, and mortality of ischemic stroke (IS) continue to rise, resulting in a serious global disease burden. The prediction models have a great value in the early prediction and diagnosis of IS. Methods: The R software was used to screen the differentially expressed genes (DEGs) of IS and control samples in the datasets GSE16561, GSE58294, and GSE37587 and analyze DEGs for enrichment analysis. The feature genes of IS were obtained by several machine learning algorithms, including the least absolute shrinkage and selector operation (LASSO) logistic regression, the support vector machine-recursive feature elimination (SVM-RFE), and the Random Forest (RF). The IS diagnostic models were constructed based on transcriptomics by machine learning and artificial neural network (ANN). Results: A total of 69 DEGs, mainly involved in immune and inflammatory responses, were identified. The pathways enriched in the IS group were complement and coagulation cascades, lysosome, PPAR signaling pathway, regulation of autophagy, and toll-like receptor signaling pathway. The feature genes selected by LASSO, SVM-RFE, and RF were 17, 10, and 12, respectively. The area under the curve (AUC) of the LASSO model in the training dataset, GSE22255, and GSE195442 was 0.969, 0.890, and 1.000. The AUC of the SVM-RFE model was 0.957, 0.805, and 1.000, respectively. The AUC of the RF model was 0.947, 0.935, and 1.000, respectively. The models have good sensitivity, specificity, and accuracy. The AUC of the LASSO+ANN, SVM-RFE+ANN, and RF+ANN models was 1.000, 0.995, and 0.997, respectively, in the training dataset. However, the AUC of LASSO+ANN, SVM-RFE+ANN, and RF+ANN models was 0.688, 0.605, and 0.619, respectively, in the GSE22255 dataset. The AUC of the LASSO+ANN and RF+ANN models was 0.740 and 0.630, respectively, in the GSE195442 dataset. In the training dataset, the sensitivity, specificity, and accuracy of the LASSO+ANN model were 1.000, 1.000, and 1.000, respectively; of the SVM-RFE+ANN model were 0.946, 0.982, and 0.964, respectively; and of the RF+ANN model were 0.964, 1.000, and 0.982, respectively. In the test datasets, the sensitivity was very satisfactory; however, the specificity and accuracy were not good. Conclusion: The LASSO, SVM-RFE, and RF models have good prediction abilities. However, the ANN model is efficient at classifying positive samples and is unsuitable at classifying negative samples.

13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(6): 1810-1816, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36476908

RESUMO

OBJECTIVE: To investigate the expression of miR-451 during erythroid differentiation and its correlation with hematological diseases. METHODS: The expression of miR-451 in erythroid differentiation of mouse hematopoietic stem cells (derived from fetal liver) was analyzed by cell culture, flow cytometry, magnetic bead sorting and qRT-PCR. The expression of miR-451 during erythroid differentiation of mouse erythroid leukemia cells (MEL) was analyzed by cell culture and qRT-PCR. The expression of miR-451 in peripheral blood of mice was detected by qRT-PCR, and the expression of miR-451 in fetal liver (14.5 days) was analyzed by microarray. The nucleated erythroid cells from bone marrow of wild type (WT) mice and ß-thalassemia (ß-thal) mice were sorted by flow cytometry, and the levels of miR-451 and erythroid genes were detected by qRT-PCR. The expression of miR-451 in peripheral blood of patients with clinical hematological diseases was detected by qRT-PCR. RESULTS: During the differentiation of mouse hematopoietic stem cells (derived from fetal liver) and MEL cells, the expression levels of miR-451 increased gradually. Compared with WT mice, the expression levels of miR-451 in peripheral blood, 14.5-day fetal liver cells and nucleated erythroid cells (sorted from bone marrow) of ß-thal mice were significantly increased(P<0.05). Many erythroid differentiation genes in nucleated erythroid cells (sorted from bone marrow) of ß-thal mice decreased. Compared with healthy controls, the expression levels of miR-451 was increased in peripheral blood of patients with ß-thalassemia and iron deficiency anemia, while the expression levels of miR-451 was decreased in patients with aplastic anemia and myelodysplastic syndrome. CONCLUSION: During erythroid differentiation, the expression levels of miR-451 increases gradually. In hematological diseases, the expression levels of miR-451 is different from that of normal controls, which is expected to become an auxiliary diagnostic index for clinical hematological diseases.


Assuntos
MicroRNAs , Talassemia beta , Camundongos , Animais , Talassemia beta/genética , Diferenciação Celular , MicroRNAs/genética
14.
mBio ; 13(5): e0141422, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36069448

RESUMO

Bacterial motility has great medical and ecological significance because of its essential role in bacterial survival and pathogenesis. Cyclic dimeric GMP (c-di-GMP), a second messenger in bacteria, is the predominant regulator of flagellar synthesis and motility and possesses turnover mechanisms that have been thoroughly investigated. Therefore, much attention has been focused on identifying the upstream stimulatory signals and downstream modules that respond to altered c-di-GMP levels. Here, we systematically analyzed c-di-GMP cyclases and phosphodiesterases in Stenotrophomonas maltophilia to screen for motility regulators. Of these enzymes, we identified and characterized a new phosphodiesterase named SisP, which was found to facilitate bacterial swimming upon stimulation with ferrous iron. SisP-mediated degradation of c-di-GMP leads to FsnR-dependent transcription of flagellar genes. Remarkably, c-di-GMP controls FsnR via two independent mechanisms: by direct binding and indirectly by modulating its phosphorylation state. In this study, we deciphered a novel "one stone, two birds" regulatory strategy of c-di-GMP and uncovered the signal that stimulates c-di-GMP hydrolysis. Facilitation of bacterial swimming motility by ferrous iron might contribute to the higher risk of bacterial infection in acutely ill patients. IMPORTANCE Stenotrophomonas maltophilia has become a great threat to human health because of the high mortality of infected patients. Swimming motility plays a crucial role in regulating bacterial virulence and adaptation. However, limited progress has been made in cyclic dimeric GMP (c-di-GMP) controlling swimming motility of S. maltophilia. Here, we characterized c-di-GMP turnover enzymes encoded by S. maltophilia and dissected the regulatory details of a phosphodiesterase named SisP. We demonstrated that SisP degrades c-di-GMP to fully activate FsnR through directly releasing FsnR from the FsnR-c-di-GMP complex and indirectly increasing its phosphorylation level. This finding uncovered a quantitative, rather than an on-off, regulatory manner employed by c-di-GMP to regulate activities of its effectors. Identification of the specific activation of SisP by ferrous iron proposes SisP as a putative drug-target for controlling bacterial infection and ferrous iron at the wounds or cuts as a putative factor contributing to the higher risk of bacterial infection.


Assuntos
GMP Cíclico , Stenotrophomonas maltophilia , Humanos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , GMP Cíclico/metabolismo , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Diester Fosfórico Hidrolases/genética , Stenotrophomonas maltophilia/genética , Stenotrophomonas maltophilia/metabolismo
15.
Cardiovasc Diabetol ; 21(1): 186, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114538

RESUMO

BACKGROUND AND AIMS: The effect of dapagliflozin (DAPA) on the prognosis of patients with acute myocardial infarction (AMI) is unclear. The present study was conducted to evaluate the association between DAPA administration and adverse events in patients with AMI undergoing percutaneous coronary intervention (PCI). METHODS: This single-center retrospective analysis study included a total of 786 patients with AMI from January 2019 to August 2021 who were or were not administered DAPA at discharge. The primary endpoint was the composite of major adverse cardiovascular events (MACE), including overall deaths, heart failure, nonfatal MI, nonfatal stroke, and unplanned repeat revascularization (URR). Differences in the triglyceride glucose (TyG) index and the atherogenic index of plasma (AIP) both during hospitalization and 12 months after discharge (if achievable) were also compared. RESULTS: During a median follow-up of 23 months, 130 patients had MACE (118 in the DAPA-free group and 12 in the DAPA group). Kaplan-Meier survival analyses revealed that the cumulative incidence of MACE (log-rank test, p = 0.009), heart failure (p = 0.003), nonfatal MI (p = 0.005), and URR (p = 0.031) was higher in the DAPA-free group. In addition, the multivariate Cox analysis showed that DAPA was significantly associated with the reduced risk of MACE (hazard ratio = 0.170, 95% confidence interval = 0.078-0.373, p < 0.001). Considering each specific adverse event, the DAPA-free group was associated with heart failure, nonfatal MI, and URR in multivariate Cox regression analyses. Stratification analyses suggested that DAPA has a strong protective effect in patients with AMI of advanced age with concomitant diabetes or those who are not on angiotensin receptor enkephalinase inhibitors. Furthermore, the TyG index and AIP of the patients 12 months after DAPA administration at discharge were significantly lower than those during hospitalization. CONCLUSIONS: DAPA is an independent protective factor against MACE and may provide incremental prognostic information in patients with AMI undergoing PCI.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Intervenção Coronária Percutânea , Compostos Benzidrílicos , Glucose , Glucosídeos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/tratamento farmacológico , Neprilisina , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Receptores de Angiotensina , Estudos Retrospectivos , Triglicerídeos
16.
J Chem Phys ; 157(5): 054704, 2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35933220

RESUMO

The design of all-solid heterogeneous catalysts with frustrated Lewis pairs (FLPs) has attracted much attention recently because of their appealing low dissociation energy for H2 molecules due to which a promotion of hydrogenation reaction is expected. The sterically encumbered Lewis acid (metal site) and base (nitrogen site) in the cavity of single transition metal atom-doped M/C2N sheets make them potential candidates for the design of catalysts with FLPs, while a comprehensive understanding of their intrinsic property and reactivity is still lacking. Calculations show that the complete dissociation of the H2 molecule into two H* states at the N sites requires two steps: heterolytic cleavage of the H2 molecule and the transfer of H* from the metal site to the N site, which are strongly related to the acidity of the metal site. Ni/C2N and Pd/C2N, which outperform the other eight transition metal atom (M) anchored M/C2N candidates, possess low energy barriers for the complete dissociation of H2 molecules, with values of only 0.30 and 0.20 eV, respectively. Furthermore, both Ni/C2N and Pd/C2N catalysts can achieve semi-hydrogenation of C2H2 into C2H4, with overall barriers of 0.81 and 0.75 eV, respectively, which are lower than those reported for many other catalysts. It is speculated that M/C2N catalysts with intrinsic FLPs may also find applications in other important hydrogenation reactions.

17.
Infect Drug Resist ; 15: 3733-3749, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859911

RESUMO

Background: Rifaximin, a rifamycin antibiotic, is widely used to treat infectious diarrhea but not commonly used in H. pylori eradication. With its potential advantages of the agent, some studies were conducted on this topic. The aim of this study is to assess effectiveness and safety of rifaximin-containing regimens and to evaluate whether they are alternative choices for H. pylori eradication. Methods: Scientific databases including PubMed, EMbase and Cochrane Library were used to identify clinical trials on rifaximin-containing regimens published from January 2000 to October 2021. Review Manager 5.4 and STATA12 were adopted for the systematic review. Results: In this study, totally 1025 patients were included from 3 randomized controlled and 9 single-arm studies. It showed that the differences in effectiveness and safety between rifaximin-containing and first-line regimens were not statistically significant in randomized controlled trials. However, the results of the single-arm trials indicated that the eradication and adverse drug reaction rate varied suggesting data instability (r=38.1%-85.4%, r ADR 0.00-67.5% by ITT analysis). Among them, the eradication rate of pediatric patients (r=85.4% by ITT analysis) was higher than that of adult patients (r=38.1-74.5% by ITT analysis). Meanwhile, in all adult subgroups (triple or quadruple, with or without amoxicillin, different duration and rifaximin dose), the results did not show sufficient effectiveness as all the eradication rates did not meet the minimum ideal or ideal target. Conclusion: Taken together, rifaximin-containing regimens should not be recommended for H. pylori eradication as they cannot achieve the eradication rate desired.

18.
Sci Rep ; 12(1): 11119, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778441

RESUMO

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.


Assuntos
Enterocolite Necrosante , Doenças do Prematuro , Estudos de Coortes , Enterocolite Necrosante/epidemiologia , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido , Doenças do Prematuro/epidemiologia
19.
World J Clin Cases ; 10(15): 4949-4956, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35801034

RESUMO

BACKGROUND: In most cases of yellow nail syndrome (YNS), the classic triad of yellow nails, lymphedema and respiratory manifestations rarely manifest simultaneously. Therefore, diagnosis is delayed or frequently missed. CASE SUMMARY: We report a 62-year-old YNS patient presenting with bilateral pleural, pericardial and peritoneal effusions who, 2 mo later, developed minimal-change nephrotic syndrome. After treatment with vitamin E, clarithromycin and prednisone for 3 mo, effusions in the chest, pericardium and abdominal cavity decreased while urine protein levels returned to within normal ranges. CONCLUSION: Clinicians should consider the possibility of YNS for patients presenting with multiple serous effusions and nephrotic syndromes.

20.
Inorg Chem ; 61(24): 9138-9146, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35658465

RESUMO

Catalytic transfer hydrogenation (CTH) of α,ß-unsaturated aldehydes using single metal atom catalysts supported on nitrogen-incorporated graphene sheet (M-Nx-Gr) materials has attracted increasing attention recently, yet the reaction mechanism remains to be explored. Compared to the Ni-N4-Gr model in which the dissociation of isopropanol is highly unfavorable as a result of steric hindrance and inertness of the Ni-N4 site embedded in graphene, the Ni-N3 site in Ni-N3-Gr is more active and facilitates the formation of *H with isopropanol as the H donor, where the dissociation of H from isopropanol with an energy barrier of 0.83 eV is the rate-determining step. An alternative reaction path starts from the coadsorption of isopropanol and furfural molecules at the Ni-N3 site, followed by a direct hydrogen transfer between the two molecules; however, the rate-determining step has a much higher energy barrier of 1.32 eV. Our calculations suggest that the hydrogenation of the aldehyde group is kinetically more favorable than the C═C hydrogenation, revealing the high chemoselectivity of furfural to furfuryl alcohol. Our investigations reveal that the CTH mechanism using the Ni-N3-Gr catalyst is different from that on traditional metal oxides, where the former has only one single active site, while two active sites are required for the latter. The proposed reaction mechanism of CTH for furfural in this study should be helpful to guide the design of single metal atom catalysts with appropriate N coordination for application in chemoselective hydrogenation reactions.

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