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1.
Chem Sci ; 15(22): 8451-8458, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38846399

ABSTRACT

Electrochemical CO2 reduction reaction (CO2RR) to multicarbon (C2+) products faces challenges of unsatisfactory selectivity and stability. Guided by finite element method (FEM) simulation, a nanoreactor with cavity structure can facilitate C-C coupling by enriching *CO intermediates, thus enhancing the selectivity of C2+ products. We designed a stable carbon-based nanoreactor with cavity structure and Cu active sites. The unique geometric structure endows the carbon-based nanoreactor with a remarkable C2+ product faradaic efficiency (80.5%) and C2+-to-C1 selectivity (8.1) during the CO2 electroreduction. Furthermore, it shows that the carbon shell could efficiently stabilize and highly disperse the Cu active sites for above 20 hours of testing. A remarkable C2+ partial current density of-323 mA cm-2 was also achieved in a flow cell device. In situ Raman spectra and density functional theory (DFT) calculation studies validated that the *COatop intermediates are concentrated in the nanoreactor, which reduces the free energy of C-C coupling. This work unveiled a simple catalyst design strategy that would be applied to improve C2+ product selectivity and stability by rationalizing the geometric structures and components of catalysts.

2.
Appl Opt ; 63(11): 2863-2867, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38856382

ABSTRACT

Using the self-developed fused indium wetting technology and planar waveguide, the uniform heat dissipation of the slab crystal and uniform pumping of the pump light were achieved, respectively. Based on the master oscillator power amplification (MOPA) scheme, the power was then amplified when the seed light source passed through the Nd:YAG slab crystal three times. Additionally, the image transfer system that we added to the amplified optical path achieved high beam quality. Finally, we obtained a rectangular pulsed laser with an output average power of 4461 W, a repetition frequency of 20 kHz, a pulse width of 62 ns, an optical-to-optical conversion efficiency of 26.8%, and a beam quality of ß x=7.0 and ß y=7.7.

3.
Lipids Health Dis ; 23(1): 163, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831433

ABSTRACT

OBJECTIVE: High low-density-lipoprotein (LDL) cholesterol has been associated with an increased risk of coronary artery diseases (CAD) including acute myocardial infarction (AMI). However, whether lipids lowering drug treatment is causally associated with decreased risk of AMI remains largely unknown. We used Mendelian randomization (MR) to evaluate the influence of genetic variation affecting the function of lipid-lowering drug targets on AMI. METHODS: Single-nucleotide polymorphisms (SNPs) associated with lipids as instruments were extracted from the Global Lipids Genetics Consortium (GLGC). The genome-wide association study (GWAS) data for AMI were obtained from UK Biobank. Two sample MR analysis was used to study the associations between high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides (TG) with AMI (n = 3,927). Genetic variants associated with LDL cholesterol at or near drug target gene were used to mimic drug effects on the AMI events in drug target MR. RESULTS: Genetically predicted higher LDL-C (per one SD increase in LDL-C of 38.67 mg/dL, OR 1.006, 95% CI 1.004-1.007) and TG (per one SD increase in TG of 90.72 mg/dL, 1.004, 1.002-1.006) was associated with increased risk of AMI, but decreased risk for higher HDL-C (per one SD increase in HDL-C of 15.51 mg/dL, 0.997, 0.995-0.999) in univariable MR. Association remained significant for LDL-C, but attenuated toward the null for HDL-C and TG in multivariable MR. Genetically proxied lower LDL-C with genetic variants at or near the PCSK9 region (drug target of evolocumab) and NPC1L1 (drug target of ezetimibe) were associated with decreased risk of AMI (0.997, 0.994-0.999 and 0.986, 0.975-0.998, respectively), whereas genetic variants at HMGCR region (drug target of statin) showed marginal association with AMI (0.995, 0.990-1.000). After excluding drug target-related SNPs, LDL-C related SNPs outside the drug target region remained a causal effect on AMI (0.994, 0.993-0.996). CONCLUSIONS: The findings suggest that genetically predicted LDL-C may play a predominant role in the development of AMI. The drug MR results imply that ezetimibe and evolocumab may decrease the risk of AMI due to their LDL-C lowering effect, and there are other non-drug related lipid lowering pathways that may be causally linked to AMI.


Subject(s)
Cholesterol, HDL , Cholesterol, LDL , Genome-Wide Association Study , Mendelian Randomization Analysis , Myocardial Infarction , Polymorphism, Single Nucleotide , Triglycerides , Humans , Myocardial Infarction/genetics , Myocardial Infarction/drug therapy , Cholesterol, LDL/blood , Triglycerides/blood , Male , Female , Cholesterol, HDL/blood , Middle Aged , Membrane Proteins/genetics , Membrane Transport Proteins/genetics , Proprotein Convertase 9/genetics , Hypolipidemic Agents/therapeutic use , Hydroxymethylglutaryl CoA Reductases/genetics , Aged
4.
J Biomed Mater Res A ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874519

ABSTRACT

Augmentation of the nasal dorsum often requires implantation of structural material. Existing methods include autologous, cadaveric or alloplastic materials and injectable hydrogels. Each of these options is associated with considerable limitations. There is an ongoing need for precise and versatile implants that produce long-lasting craniofacial augmentation. Four separate polylactic acid (PLA) dorsal nasal implant designs were 3D-printed. Two implants had internal PLA rebar of differing porosities and two were designed as "shells" of differing porosities. Shell designs were implanted without infill or with either minced or zested processed decellularized ovine cartilage infill to serve as a "biologic rebar", yielding eight total treatment groups. Scaffolds were implanted heterotopically on rat dorsa (N = 4 implants per rat) for explant after 3, 6, and 12 months followed by volumetric, histopathologic, and biomechanical analysis. Low porosity implants with either minced cartilage or PLA rebar infill had superior volume retention across all timepoints. Overall, histopathologic and immunohistochemical analysis showed a resolving inflammatory response with an M1/M2 ratio consistently favoring tissue regeneration over the study course. However, xenograft cartilage showed areas of degradation and pro-inflammatory infiltrate contributing to volume and contour loss over time. Biomechanical analysis revealed all constructs had equilibrium and instantaneous moduli higher than human septal cartilage controls. Biocompatible, degradable polymer implants can induce healthy neotissue ingrowth resulting in guided soft tissue augmentation and offer a simple, customizable and clinically-translatable alternative to existing craniofacial soft tissue augmentation materials. PLA-only implants may be superior to combination PLA and xenograft implants due to contour irregularities associated with cartilage degradation.

5.
Acta Chim Slov ; 71(2): 295-303, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38919097

ABSTRACT

A new phenanthroline derivative bearing imidazole group, (2-(3,5-di(pyridin-4-yl)phenyl)-1-p-tolyl-1H-imidazo[4,5-f][1,10]phenanthroline) (1), has been devised. 1 can be used as a multifunctional probe exhibiting a highly sensitive colorimetric response to Fe2+ and a selectively ratiometric fluorescent response to Zn2+ in a buffer-ethanol solution. The absorption enhancement accompanied by a visual color change from colorless to red upon addition of Fe2+, makes 1 a suitable naked-eye sensor for Fe2+. Moreover, 1 displayed a Zn2+-induced red-shift of emission (44 nm) showing a color change from blue to light cyan under a 365-nm UV lamp. Its practical imaging applicability for intracellular Zn2+ was confirmed in HeLa cells using a confocal microscope. The improved emission properties and cell imaging capability would provide a new approach for fluorescence sensation for Zn2+.

6.
Article in English | MEDLINE | ID: mdl-38772315

ABSTRACT

Owing to population growth and environmental pollution, freshwater aquaculture has been rapidly shrinking in recent years. Aquaculture in saline-alkaline waters is a crucial strategy to meet the increasing demand for aquatic products. The Chinese mitten crab is an important economic food in China, but the molecular mechanism by which it tolerates carbonate alkalinity (CA) in water remains unclear. Here, we found that enzyme activities of the tricarboxylic acid (TCA) cycle in the gills, such as citrate synthase, isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, and malate dehydrogenase, were markedly reduced under CA stress induced by 40 mM NaHCO3. Secondly, the TCA cycle in the gills is inhibited under acute CA stress, according to proteomic and metabolomic analyses. The expressions of six enzymes, namely aconitate hydratase, isocitrate dehydrogenase, 2-oxoglutarate dehydrogenase, dihydrolipoyl dehydrogenase, succinate-CoA ligase, and malate dehydrogenase, were downregulated, resulting in the accumulation of phosphoenolpyruvic acid, citric acid, cis-aconitate, and α-ketoglutaric acid. Finally, we testified that if the TCA cycle is disturbed by malonate, the survival rate increases in CA water. To our knowledge, this is the first study to show that the TCA cycle in the gills is inhibited under CA stress. Overall, the results provide new insights into the molecular mechanism of tolerance to saline-alkaline water in crabs, which helped us expand the area for freshwater aquaculture and comprehensively understand the physiological characteristics of crab migration.


Subject(s)
Brachyura , Carbonates , Citric Acid Cycle , Gills , Stress, Physiological , Animals , Citric Acid Cycle/drug effects , Gills/metabolism , Gills/drug effects , Brachyura/metabolism , Brachyura/physiology , Brachyura/drug effects , Carbonates/pharmacology
7.
J Med Chem ; 67(11): 9431-9446, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38818879

ABSTRACT

Synthetic lethality has recently emerged as a new approach for the treatment of mutated genes that were previously considered undruggable. Targeting methionine adenosyltransferase 2A (MAT2A) in cancers with deletion of the methylthioadenosine phosphorylase (MTAP) gene leads to synthetic lethality and thus has attracted significant interest in the field of precise anticancer drug development. Herein, we report the discovery of a series of novel MAT2A inhibitors featuring a pyrazolo[3,4-c]quinolin-4-one skeleton based on structure-based drug design. Further optimization led to compound 39, which has a high potency for inhibiting MAT2A and a remarkable selectivity for MTAP-deleted cancer cell lines. Compound 39 has a favorable pharmacokinetic profile with high plasma exposure and oral bioavailability, and it exhibits significant efficacy in xenograft MTAP-depleted models. Moreover, 39 demonstrates excellent brain exposure with a Kpuu of 0.64 in rats.


Subject(s)
Brain , Drug Design , Enzyme Inhibitors , Methionine Adenosyltransferase , Methionine Adenosyltransferase/antagonists & inhibitors , Methionine Adenosyltransferase/metabolism , Humans , Animals , Structure-Activity Relationship , Rats , Brain/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/chemical synthesis , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Mice , Male , Rats, Sprague-Dawley , Xenograft Model Antitumor Assays
9.
Ecotoxicol Environ Saf ; 279: 116496, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38816322

ABSTRACT

Microbially induced carbonate precipitation (MICP), as an eco-friendly and promising technology that can transform free metal ions into stable precipitation, has been extensively used in remediation of heavy metal contamination. However, its depressed efficiency of heavy metal elimination remains in question due to the inhibition effect of heavy metal toxicity on bacterial activity. In this work, an efficient, low-cost manganese (Mn) elimination strategy by coupling MICP with chitosan biopolymer as an additive with reduced treatment time was suggested, optimized, and implemented. The influences of chitosan at different concentrations (0.01, 0.05, 0.10, 0.15 and 0.30 %, w/v) on bacterial growth, enzyme activity, Mn removal efficiency and microstructure properties of the resulting precipitation were investigated. Results showed that Mn content was reduced by 94.5 % within 12 h with 0.15 % chitosan addition through adsorption and biomineralization as MnCO3 (at an initial Mn concentration of 3 mM), demonstrating a two-thirds decrease in remediation time compared to the chitosan-absent system, whereas maximum urease activity increased by ∼50 %. Microstructure analyses indicated that the mineralized precipitates were spherical-shaped MnCO3, and a smaller size and more uniform distribution of MnCO3 is obtained by the regulation of abundant amino and hydroxyl groups in chitosan. These results demonstrate that chitosan accelerates nucleation and tunes the growth of MnCO3 by providing nucleation sites for mineral formation and alleviating the toxicity of metal ions, which has the potential to upgrade MICP process in a sustainable and effective manner. This work provides a reference for further understanding of the biomineralization regulation mechanism, and gives a new perspective into the application of biopolymer-intensified strategies of MICP technology in heavy metal contamination.


Subject(s)
Carbonates , Chitosan , Manganese , Chitosan/chemistry , Manganese/chemistry , Manganese/toxicity , Carbonates/chemistry , Adsorption , Biopolymers/chemistry , Chemical Precipitation , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/chemistry , Urease , Environmental Restoration and Remediation/methods , Biomineralization/drug effects , Biodegradation, Environmental
10.
Aging Cell ; : e14173, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38725159

ABSTRACT

Observational studies have suggested that the use of antihypertensive drugs was associated with the risk of frailty; however, these findings may be biased by confounding and reverse causality. This study aimed to explore the effect of genetically predicted lifelong lowering blood pressure (BP) through different antihypertensive medications on frailty. One-sample Mendelian randomization (MR) and summary data-based MR (SMR) were applied. We utilized two kinds of genetic instruments to proxy the antihypertensive medications, including genetic variants within or nearby drugs target genes associated with systolic/diastolic BP, and expression level of the corresponding gene. Among 298,618 UK Biobank participants, one-sample MR analysis observed that genetically proxied BB use (relative risk ratios, 0.76; 95% CI, 0.65-0.90; p = 0.001) and CCB use (0.83; 0.72-0.95; p = 0.007), equivalent to a 10-mm Hg reduction in systolic BP, was significantly associated with lower risk of pre-frailty. In addition, although not statistically significant, the effect directions of systolic BP through ACEi variants (0.72; 0.39-1.33; p = 0.296) or thiazides variants (0.74; 0.53-1.03; p = 0.072) on pre-frailty were also protective. Similar results were obtained in analyses for diastolic BP. SMR of expression in artery showed that decreased expression level of KCNH2, a target gene of BBs, was associated with lower frailty index (beta -0.02, p = 2.87 × 10-4). This MR analysis found evidence that the use of BBs and CCBs was potentially associated with reduced frailty risk in the general population, and identified KCNH2 as a promising target for further clinical trials to prevent manifestations of frailty.

11.
Abdom Radiol (NY) ; 2024 May 05.
Article in English | MEDLINE | ID: mdl-38704783

ABSTRACT

OBJECTIVE: To compare radiomics and non-radiomics in predicting early recurrence (ER) in patients with hepatocellular carcinoma (HCC) after curative surgery. METHODS: We systematically searched PubMed and Embase databases. Studies with clear reference criteria were selected. Data were extracted and assessed for quality using the quality in prognosis studies tool (QUIPS) by two independent authors. All included radiomics studies underwent radiomics quality score (RQS) assessment. We calculated sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using random or fixed models with a 95%CI. Forest maps visualized the data, and summary receiver operating characteristic (sROC) curves with the area under the curve (AUC) were generated. Meta-regression and subgroup analyses explored sources of heterogeneity. We compared sensitivity, specificity, PLR, and NLR using the z-test and compared AUC values using the Delong test. RESULTS: Our meta-analysis included 10 studies comprising 1857 patients. For radiomics, the pooled sensitivity, specificity, AUC of sROC, PLR and NLR were 0.84(95%CI: 0.78-0.89), 0.80(95%CI: 0.75-0.85), 0.89(95%CI: 0.86-0.91), 4.28(95%CI: 3.48-5.27) and 0.20(95%CI: 0.14-0.27), respectively, but with significant heterogeneity (I2 = 60.78% for sensitivity, I2 = 55.79% for specificity) and potential publication bias (P = 0.04). The pooled sensitivity, specificity, AUC of sROC, PLR, NLR for non-radiomics were 0.75(95%CI:0.68-0.81), 0.78(95%CI:0.72-0.83), 0.83(95%CI: 0.80-0.86), 3.45(95%CI: 2.68-4.44) and 0.32(95%CI: 0.24-0.41), respectively. There was no significant heterogeneity in this group (I2 = 0% for sensitivity, I2 = 17.27% for specificity). Radiomics showed higher diagnostic accuracy (AUC: 0.89 vs. 0.83, P = 0.0456), higher sensitivity (0.84 vs. 0.75, P = 0.0385) and lower NLR (0.20 vs. 0.32, P = 0.0287). CONCLUSION: The radiomics from preoperative MRI effectively predicts ER of HCC and has higher diagnostic accuracy than non-radiomics. Due to potential publication bias and suboptimal RQS scores in radiomics, these results should be interpreted cautiously.

12.
Atherosclerosis ; : 117553, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38811283

ABSTRACT

BACKGROUND AND AIMS: Reproductive risk factors are associated with increased risk of cardiovascular disease (CVD) in women. However, the combined effects of the composite reproductive risk factors on CVD are unknown. This study was performed to construct a reproductive risk score (RRS) to measure reproductive status, examine the association between RRS and CVD, and explore the modification effect of healthy lifestyle on the association in women in the UK Biobank cohort. METHODS: The RRS was constructed in 74,141 female participants with data about the items derived for the RRS in the UK Biobank. The RRS was derived from 17 baseline variables, all of which indicated women's reproductive health status. We defined four categories of RRS status: low-risk group (score 0-1); low-intermediate group (score 2-3); high-intermediate group (score 4-5); and high-risk group (score 6-13). We also constructed a healthy lifestyle score (HLS) with five related factors, and categorized into unhealthy lifestyle group (score: 0-1), intermediate lifestyle group (score: 2-3) and healthy lifestyle group (score: 4-5). RESULTS: Each point increase in the RRS was associated with a 22 % higher risk of CVD (adjusted hazard ratio (aHR): 1.22; 95 % confidence interval (CI): 1.16 to 1.28), 23 % higher risk of IHD (1.23; 1.17 to 1.31) and 19 % higher risk of stroke (1.19; 1.07 to 1.32). The percentage population-attribution risks (PAR%) were 16 % (95 % CI: 8 to 24) for CVD, 15 % (95 % CI: 6 to 24) for IHD and 18 % (95 % CI: 1 to 33) for stroke. A healthy lifestyle significantly attenuated RRS associations with the incidence of CVD and IHD. The attributable proportions due to additive interaction (p < 0.001) between RRS and HLS were 0.14 (95 % CI: 0.07 to 0.22) for CVD and 0.15 (95 % CI: 0.09 to 0.23) for IHD, respectively. CONCLUSIONS: High RRS was associated with increased risks of CVD, IHD and stroke in female participants in the UK Biobank. The early-stage identification of women with reproductive risk using synthesised indicators and appropriate healthy lifestyle interventions could be useful for the prevention of early CVD and the extension of healthy active life expectancy.

13.
Nano Lett ; 24(21): 6278-6285, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38758393

ABSTRACT

Topological Dirac nodal-line semimetals host topologically nontrivial electronic structure with nodal-line crossings around the Fermi level, which could affect the photocarrier dynamics and lead to novel relaxation mechanisms. Herein, by using time- and angle-resolved photoemission spectroscopy, we reveal the previously inaccessible linear dispersions of the bulk conduction bands above the Fermi level in a Dirac nodal-line semimetal PtSn4, as well as the momentum and temporal evolution of the gapless nodal lines. A surprisingly ultrafast relaxation dynamics within a few hundred femtoseconds is revealed for photoexcited carriers in the nodal line. Theoretical calculations suggest that such ultrafast carrier relaxation is attributed to the multichannel scatterings among the complex metallic bands of PtSn4 via electron-phonon coupling. In addition, a unique dynamic relaxation mechanism contributed by the highly anisotropic Dirac nodal-line electronic structure is also identified. Our work provides a comprehensive understanding of the ultrafast carrier dynamics in a Dirac nodal-line semimetal.

14.
Pain Ther ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38743247

ABSTRACT

Cortical spreading depression (CSD) is a slow wave of cortical depolarization closely associated with migraines with an aura. Previously, it was thought that CSD depolarization was mainly driven by neurons, with characteristic changes in neuronal swelling and increased extracellular potassium (K+) and glutamate. However, the role of astrocytes, a member of the neurovascular unit, in migraine with CSD has recently received increasing attention. In the early stages of CSD, astrocytes provide neurons with energy support and clear K+ and glutamate from synaptic gaps. However, in the late stages of CSD, astrocytes release large amounts of lactic acid to exacerbate hypoxia when the energy demand exceeds the astrocytes' compensatory capacity. Astrocyte endfoot swelling is a characteristic of CSD, and neurons are not similarly altered. It is primarily due to K+ influx and abnormally active calcium (Ca2+) signaling. Aquaporin 4 (AQP-4) only mediates K+ influx and has little role as an aquaporin. Astrocytes endfoot swelling causes perivascular space closure, slowing the glymphatic system flow and exacerbating neuroinflammation, leading to persistent CSD. Astrocytes are double-edged swords in migraine with CSD and may be potential targets for CSD interventions.

15.
Small ; : e2401464, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38616766

ABSTRACT

Organic-inorganic hybrid linear and nonlinear optical (NLO) materials have received increasingly wide spread attention in recent years. Herein, the first hybrid noncentrosymmetric (NCS) borophosphate, (C5H6N)2B2O(HPO4)2 (4PBP), is rationally designed and synthesized by a covalent-linkage strategy. 4-pyridyl-boronic acid (4 PB) is considered as a bifunctional unit, which may effectively improve the optical properties and stability of the resultant material. On the one hand, 4 PB units are covalently linked with PO3(OH) groups via strong B-O-P connections, which significantly enhances the thermal stability of 4PBP (decomposition at 321, vs lower 200 °C of most of hybrid materials). On the other hand, the planar π-conjugated C5H6N units and their uniform layered arrangements represent large structural anisotropy and hyperpolarizability, achieving the largest birefringence (0.156 @ 546 nm) in the reported borophosphates and a second-harmonic generation response (0.7 × KDP). 4PBP also exhibits a wide transparency range (0.27-1.50 µm). This work not only provides a promising birefringent material, but also offers a practical covalent-attachment strategy for the rational design of new high-performance optical materials.

16.
Diabetes Metab Res Rev ; 40(4): e3803, 2024 May.
Article in English | MEDLINE | ID: mdl-38581399

ABSTRACT

AIMS: We aimed to examine the longitudinal associations of birth weight with plasma metabolites in adulthood, and further quantify the proportions of the links between birth weight and incident adult type 2 diabetes (T2D) that were mediated by plasma metabolites. MATERIALS AND METHODS: A total of 62,033 participants with complete nuclear magnetic resonance metabolomics and birth weight data from the UK Biobank were included in this study. Linear regression was used to assess the associations between birth weight and metabolites. Cox regression was used to estimate hazard ratios for T2D associated with metabolites. We further performed mediation analyses to estimate the extent to which metabolites might mediate the association between birth weight and T2D risk. RESULTS: Low birth weight was associated with the adverse metabolic responses across multiple metabolic pathways, including lipoprotein subclasses, amino acids, fatty acids (FA), and inflammation. Metabolites associated with higher birth weight tended to be associated with a lower risk of T2D (Pearson correlation coefficient: -0.85). A total of 62 metabolites showed statistically significant mediation effects in the protective association of higher birth weight and T2D risk, including large-sized very low-density lipoprotein particles and triglyceride concentrations as well as saturated, and monounsaturated FA and glycoprotein acetyls. CONCLUSIONS: We identified a range of metabolites that reflect the adult metabolic response to birth weight, some of which might lie on the pathway between birth weight and adult T2D risk.


Subject(s)
Diabetes Mellitus, Type 2 , Adult , Humans , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/etiology , Birth Weight , Biomarkers , Metabolome , Metabolomics
18.
J Basic Microbiol ; 64(6): e2300751, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38644586

ABSTRACT

NAD+-dependent (2 R,3 R)­2,3­butanediol dehydrogenase (BDH) from Neisseria gonorrhoeae (NgBDH) is a representative member of the medium-chain dehydrogenase/reductase (MDR) superfamily. To date, little information is available on the substrate binding sites and catalytic residues of BDHs from this superfamily. In this work, according to molecular docking studies, we found that conserved residues Phe120 and Val161 form strong hydrophobic interactions with both (2 R,3 R)­2,3­butanediol (RR-BD) and meso-2,3­butanediol (meso-BD) and that mutations of these residues to alanine or threonine impair substrate binding. To further evaluate the roles of these two residues, Phe120 and Val161 were mutated to alanine or threonine. Kinetic analysis revealed that, relative to those of wild type, the apparent KM values of the Phe120Ala mutant for RR-BD and meso-BD increased 36- and 369-fold, respectively; the catalytic efficiencies of this mutant with RR-BD and meso-BD decreased approximately 586- and 3528-fold, respectively; and the apparent KM values of the Val161Ala mutant for RR-BD and meso-BD increased 4- and 37-fold, respectively, the catalytic efficiencies of this mutant with RR-BD and meso-BD decreased approximately 3- and 28-fold, respectively. Additionally, the Val161Thr mutant slightly decreased catalytic efficiencies (twofold with RR-BD; 7.3-fold with meso-BD) due to an increase in KM (sixfold for RR-BD; 24-fold for meso-BD) and a slight increase (2.8-fold with RR-BD; 3.3-fold with meso-BD) in kcat. These findings validate the critical roles of Phe120 and Val161 of NgBDH in substrate binding and catalysis. Overall, the current study provides a better understanding of the substrate binding and catalysis of BDHs within the MDR superfamily.


Subject(s)
Alcohol Oxidoreductases , Butylene Glycols , Molecular Docking Simulation , Mutagenesis, Site-Directed , Neisseria gonorrhoeae , Phenylalanine , Neisseria gonorrhoeae/enzymology , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/metabolism , Alcohol Oxidoreductases/genetics , Alcohol Oxidoreductases/metabolism , Alcohol Oxidoreductases/chemistry , Kinetics , Butylene Glycols/metabolism , Phenylalanine/metabolism , Phenylalanine/genetics , Binding Sites , Substrate Specificity , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Valine/metabolism , Valine/genetics , Catalytic Domain , Hydrophobic and Hydrophilic Interactions
19.
BMC Cancer ; 24(1): 532, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38671389

ABSTRACT

BACKGROUND: Aberrant expressions of desmoglein 2 (Dsg2) and desmocollin 2(Dsc2), the two most widely distributed desmosomal cadherins, have been found to play various roles in cancer in a context-dependent manner. Their specific roles on breast cancer (BC) and the potential mechanisms remain unclear. METHODS: The expressions of Dsg2 and Dsc2 in human BC tissues and cell lines were assessed by using bioinformatics analysis, immunohistochemistry and western blotting assays. Wound-healing and Transwell assays were performed to evaluate the cells' migration and invasion abilities. Plate colony-forming and MTT assays were used to examine the cells' capacity of proliferation. Mechanically, Dsg2 and Dsc2 knockdown-induced malignant behaviors were elucidated using western blotting assay as well as three inhibitors including MK2206 for AKT, PD98059 for ERK, and XAV-939 for ß-catenin. RESULTS: We found reduced expressions of Dsg2 and Dsc2 in human BC tissues and cell lines compared to normal counterparts. Furthermore, shRNA-mediated downregulation of Dsg2 and Dsc2 could significantly enhance cell proliferation, migration and invasion in triple-negative MDA-MB-231 and luminal MCF-7 BC cells. Mechanistically, EGFR activity was decreased but downstream AKT and ERK pathways were both activated maybe through other activated protein tyrosine kinases in shDsg2 and shDsc2 MDA-MB-231 cells since protein tyrosine kinases are key drivers of triple-negative BC survival. Additionally, AKT inhibitor treatment displayed much stronger capacity to abolish shDsg2 and shDsc2 induced progression compared to ERK inhibition, which was due to feedback activation of AKT pathway induced by ERK inhibition. In contrast, all of EGFR, AKT and ERK activities were attenuated, whereas ß-catenin was accumulated in shDsg2 and shDsc2 MCF-7 cells. These results indicate that EGFR-targeted therapy is not a good choice for BC patients with low Dsg2 or Dsc2 expression. Comparatively, AKT inhibitors may be more helpful to triple-negative BC patients with low Dsg2 or Dsc2 expression, while therapies targeting ß-catenin can be considered for luminal BC patients with low Dsg2 or Dsc2 expression. CONCLUSION: Our finding demonstrate that single knockdown of Dsg2 or Dsc2 could promote proliferation, motility and invasion in triple-negative MDA-MB-231 and luminal MCF-7 cells. Nevertheless, the underlying mechanisms were cellular context-specific and distinct.


Subject(s)
Cell Movement , Cell Proliferation , Desmocollins , Desmoglein 2 , Triple Negative Breast Neoplasms , Humans , Desmocollins/metabolism , Desmocollins/genetics , Desmoglein 2/metabolism , Desmoglein 2/genetics , Female , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Triple Negative Breast Neoplasms/genetics , Cell Line, Tumor , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Neoplasm Invasiveness , Gene Expression Regulation, Neoplastic , beta Catenin/metabolism , Signal Transduction
20.
World J Orthop ; 15(4): 363-378, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38680671

ABSTRACT

BACKGROUND: Regular physical activity during childhood and adolescence is beneficial to bone development, as evidenced by the ability to increase bone density and peak bone mass by promoting bone formation. AIM: To investigate the effects of exercise on bone formation in growing mice and to investigate the underlying mechanisms. METHODS: 20 growing mice were randomly divided into two groups: Con group (control group, n = 10) and Ex group (treadmill exercise group, n = 10). Hematoxylin-eosin staining, immunohistochemistry, and micro-CT scanning were used to assess the bone formation-related indexes of the mouse femur. Bioinformatics analysis was used to find potential miRNAs targets of long non-coding RNA H19 (lncRNA H19). RT-qPCR and Western Blot were used to confirm potential miRNA target genes of lncRNA H19 and the role of lncRNA H19 in promoting osteogenic differentiation. RESULTS: Compared with the Con group, the expression of bone morphogenetic protein 2 was also significantly increased. The micro-CT results showed that 8 wk moderate-intensity treadmill exercise significantly increased bone mineral density, bone volume fraction, and the number of trabeculae, and decreased trabecular segregation in the femur of mice. Inhibition of lncRNA H19 significantly upregulated the expression of miR-149 and suppressed the expression of markers of osteogenic differentiation. In addition, knockdown of lncRNA H19 significantly downregulated the expression of autophagy markers, which is consistent with the results of autophagy-related protein changes detected in mouse femurs by immunofluorescence. CONCLUSION: Appropriate treadmill exercise can effectively stimulate bone formation and promote the increase of bone density and bone volume in growing mice, thus enhancing the peak bone mass of mice. The lncRNA H19/miR-149 axis plays an important regulatory role in osteogenic differentiation.

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