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1.
Nature ; 600(7887): 81-85, 2021 12.
Article in English | MEDLINE | ID: mdl-34853456

ABSTRACT

Understanding the structure and dynamic process of water at the solid-liquid interface is an extremely important topic in surface science, energy science and catalysis1-3. As model catalysts, atomically flat single-crystal electrodes exhibit well-defined surface and electric field properties, and therefore may be used to elucidate the relationship between structure and electrocatalytic activity at the atomic level4,5. Hence, studying interfacial water behaviour on single-crystal surfaces provides a framework for understanding electrocatalysis6,7. However, interfacial water is notoriously difficult to probe owing to interference from bulk water and the complexity of interfacial environments8. Here, we use electrochemical, in situ Raman spectroscopic and computational techniques to investigate the interfacial water on atomically flat Pd single-crystal surfaces. Direct spectral evidence reveals that interfacial water consists of hydrogen-bonded and hydrated Na+ ion water. At hydrogen evolution reaction (HER) potentials, dynamic changes in the structure of interfacial water were observed from a random distribution to an ordered structure due to bias potential and Na+ ion cooperation. Structurally ordered interfacial water facilitated high-efficiency electron transfer across the interface, resulting in higher HER rates. The electrolytes and electrode surface effects on interfacial water were also probed and found to affect water structure. Therefore, through local cation tuning strategies, we anticipate that these results may be generalized to enable ordered interfacial water to improve electrocatalytic reaction rates.

2.
Nucleic Acids Res ; 52(6): 3011-3030, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38227944

ABSTRACT

DNA replication is a major source of endogenous DNA damage in tumor cells and a key target of cellular response to genotoxic stress. DNA replication can be deregulated by oncoproteins, such as transcription factor MYC, aberrantly activated in many human cancers. MYC is stringently regulated by the ubiquitin system - for example, ubiquitination controls recruitment of the elongation factor PAF1c, instrumental in MYC activity. Curiously, a key MYC-targeting deubiquitinase USP28 also controls cellular response to DNA damage via the mediator protein 53BP1. USP28 forms stable dimers, but the biological role of USP28 dimerization is unknown. We show here that dimerization limits USP28 activity and restricts recruitment of PAF1c by MYC. Expression of monomeric USP28 stabilizes MYC and promotes PAF1c recruitment, leading to ectopic DNA synthesis and replication-associated DNA damage. USP28 dimerization is stimulated by 53BP1, which selectively binds USP28 dimers. Genotoxic stress diminishes 53BP1-USP28 interaction, promotes disassembly of USP28 dimers and stimulates PAF1c recruitment by MYC. This triggers firing of DNA replication origins during early response to genotoxins and exacerbates DNA damage. We propose that dimerization of USP28 prevents ectopic DNA replication at transcriptionally active chromatin to maintain genome stability.


Subject(s)
DNA Damage , Humans , Deubiquitinating Enzymes/genetics , DNA/metabolism , Neoplasms , Ubiquitin Thiolesterase/genetics , Ubiquitin Thiolesterase/metabolism , Ubiquitination
3.
Brief Bioinform ; 23(4)2022 07 18.
Article in English | MEDLINE | ID: mdl-35649341

ABSTRACT

Cell-free DNA (cfDNA) provides a convenient diagnosis avenue for noninvasive cancer detection. The current methods are focused on identifying circulating tumor DNA (ctDNA)s genomic aberrations, e.g. mutations, copy number aberrations (CNAs) or methylation changes. In this study, we report a new computational method that unifies two orthogonal pieces of information, namely methylation and CNAs, derived from whole-genome bisulfite sequencing (WGBS) data to quantify low tumor content in cfDNA. It implements a Bayes model to enrich ctDNA from WGBS data based on hypomethylation haplotypes, and subsequently, models CNAs for cancer detection. We generated WGBS data in a total of 262 samples, including high-depth (>20×, deduped high mapping quality reads) data in 76 samples with matched triplets (tumor, adjacent normal and cfDNA) and low-depth (~2.5×, deduped high mapping quality reads) data in 186 samples. We identified a total of 54 Mb regions of hypomethylation haplotypes for model building, a vast majority of which are not covered in the HumanMethylation450 arrays. We showed that our model is able to substantially enrich ctDNA reads (tens of folds), with clearly elevated CNAs that faithfully match the CNAs in the paired tumor samples. In the 19 hepatocellular carcinoma cfDNA samples, the estimated enrichment is as high as 16 fold, and in the simulation data, it can achieve over 30-fold enrichment for a ctDNA level of 0.5% with a sequencing depth of 600×. We also found that these hypomethylation regions are also shared among many cancer types, thus demonstrating the potential of our framework for pancancer early detection.


Subject(s)
Cell-Free Nucleic Acids , Circulating Tumor DNA , Neoplasms , Bayes Theorem , Biomarkers, Tumor/genetics , Cell-Free Nucleic Acids/genetics , Circulating Tumor DNA/genetics , DNA Copy Number Variations , DNA Methylation , Humans , Neoplasms/diagnosis , Neoplasms/genetics
4.
J Magn Reson Imaging ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38777575

ABSTRACT

BACKGROUND: Neonates with immature auditory function (eg, weak/absent middle ear muscle reflex) could conceivably be vulnerable to noise-induced hearing loss; however, it is unclear if neonates show evidence of hearing loss following MRI acoustic noise exposure. PURPOSE: To explore the auditory effects of MRI acoustic noise in neonates. STUDY TYPE: Prospective. SUBJECTS: Two independent cohorts of neonates (N = 19 and N = 18; mean gestational-age, 38.75 ± 2.18 and 39.01 ± 1.83 weeks). FIELD STRENGTH/SEQUENCE: T1-weighted three-dimensional gradient-echo sequence, T2-weighted fast spin-echo sequence, single-shot echo-planar imaging-based diffusion-tensor imaging, single-shot echo-planar imaging-based diffusion-kurtosis imaging and T2-weighted fluid-attenuated inversion recovery sequence at 3.0 T. ASSESSMENT: All neonates wore ear protection during scan protocols lasted ~40 minutes. Equivalent sound pressure levels (SPLs) were measured for both cohorts. In cohort1, left- and right-ear auditory brainstem response (ABR) was measured before (baseline) and after (follow-up) MRI, included assessment of ABR threshold, wave I, III and V latencies and interpeak interval to determine the functional status of auditory nerve and brainstem. In cohort2, baseline and follow-up left- and right-ear distortion product otoacoustic emission (DPOAE) amplitudes were assessed at 1.2 to 7.0 kHz to determine cochlear function. STATISTICAL TEST: Wilcoxon signed-rank or paired t-tests with Bonferroni's correction were used to compare the differences between baseline and follow-up ABR and DPOAE measures. RESULTS: Equivalent SPLs ranged from 103.5 to 113.6 dBA. No significant differences between baseline and follow-up were detected in left- or right-ear ABR measures (P > 0.999, Bonferroni corrected) in cohort1, or in DPOAE levels at 1.2 to 7.0 kHz in cohort2 (all P > 0.999 Bonferroni corrected except for left-ear levels at 3.5 and 7.0 kHz with corrected P = 0.138 and P = 0.533). DATA CONCLUSION: A single 40-minute 3-T MRI with equivalent SPLs of 103.5-113.6 dBA did not result in significant transient disruption of auditory function, as measured by ABR and DPOAE, in neonates with adequate hearing protection. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 5.

5.
Environ Sci Technol ; 58(8): 3755-3765, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38285506

ABSTRACT

Carbon dioxide removal (CDR) is necessary for reaching net zero emissions, with studies showing potential deployment at multi-GtCO2 scale by 2050. However, excessive reliance on future CDR entails serious risks, including delayed emissions cuts, lock-in of fossil infrastructure, and threats to sustainability from increased resource competition. This study highlights an alternative pathway─prioritizing near-term non-CDR mitigation and minimizing CDR dependence. We impose a 1 GtCO2 limit on global novel CDR deployment by 2050, forcing aggressive early emissions reductions compared to 8-22 GtCO2 in higher CDR scenarios. Our results reveal that this low CDR pathway significantly decreases fossil fuel use, greenhouse gas (GHG) emissions, and air pollutants compared to higher CDR pathways. Driving rapid energy transitions eases pressures on land (including food cropland), water, and fertilizer resources required for energy and negative emissions. However, these sustainability gains come with higher mitigation costs from greater near-term low/zero-carbon technology deployment for decarbonization. Overall, this work provides strong evidence for maximizing non-CDR strategies such as renewables, electrification, carbon neutral/negative fuels, and efficiency now rather than betting on uncertain future CDR scaling. Ambitious near-term mitigation in this decade is essential to prevent lock-in and offer the best chance of successful deep decarbonization. Our constrained CDR scenario offers a robust pathway to achieving net zero emissions with limited sustainability impacts.


Subject(s)
Carbon Dioxide , Greenhouse Gases , Carbon Dioxide/analysis
6.
Phys Chem Chem Phys ; 26(23): 16637-16645, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38808387

ABSTRACT

The rapid recombination of photogenerated electrons and holes greatly limits the efficiency of photocatalyst based on semiconductor. In order to address this issue, we predicted a novel ferroelectric polarized heterojunction photocatalyst, CdS/In2Se3, which enables the spontaneous overall water splitting reaction. The CdS/In2Se3 heterojunction exhibits a band-edge staggered alignment and it is easy to form a direct Z-scheme charge transfer pathway. Besides, the built-in electric field (Eint) in the CdS/In2Se3 heterojunction promoted the charge transfer of CdS/In2Se3, leading to an improved separating efficiency of photo-generated carriers. Moreover, the vertical intrinsic polarized electric field (Ep) not only alters the position of the band edge but also reduces the bandgap limitations commonly associated with photocatalytic materials. Furthermore, the CdS/In2Se3 heterojunctions demonstrate separate catalytic activity for the hydrogen evolution reaction (HER) on the surface of the CdS monolayer and oxygen evolution reaction (OER) on the surface of In2Se3, respectively. Notably, the CdS/In2Se3-down configuration enables spontaneous photocatalytic water splitting in pH = 7, while the CdS/In2Se3-up configuration efficiently facilitates the HER process. This study highlights the significant advantages of CdS/In2Se3 heterojunctions as photocatalytic materials, offering unique insights into the development and research of this promising heterojunction architecture.

7.
Phys Chem Chem Phys ; 26(3): 2134-2139, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38131398

ABSTRACT

Exploring intrinsic two-dimensional (2D) ferromagnetic (FM) materials with high Curie temperatures (TC) and large magnetic anisotropy energies (MAE) is one of the effective solutions to develop materials for high-performance spintronic applications. Using density functional theory calculations and high-throughput computations, we predict an intrinsic bimetallic FM monolayer, CrAuTe2, which has a large MAE and high TC. The results show that the value of the MAE can reach about 1.5 meV per Cr, and Monte Carlo simulations show that the TC of monolayer CrAuTe2 is about 840 K. Further analysis indicates that the joint effects of spin-orbit coupling (SOC) interaction and magnetic dipole-dipole interaction result in high in-plane magnetic anisotropy. In addition, this monolayer has good dynamic, thermal, and mechanical stabilities, which were confirmed by ab initio molecular dynamics simulations, phonon spectra, and elastic constants, respectively. In order to propose a practical synthesis approach, we built a CrAuTe2/graphene van der Waals heterostructure, and found that the heterostructure does not affect the magnetic properties of monolayer CrAuTe2. These findings appear promising for the future applications in nano-spintronics.

8.
Phys Chem Chem Phys ; 26(23): 16891-16897, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38833218

ABSTRACT

The interfaces between heavy metals and antiferromagnetic materials have garnered significant attention due to their interesting physical properties. La0.35Sr0.65MnO3 (LSMO), as a typical manganite, exhibits an antiferromagnetic ground state that can be controlled through epitaxial strain and interfacial spin-orbit coupling. In this work, we reported the diverse magnetoresistance, influenced by the interfacial magnetic state, in Pt (3 nm)/LSMO (6-20 nm) heterostructures. The strong spin-orbit coupling of Pt and Dzyaloshinskii-Moriya interaction alter the spin structure and enhance the electron scattering at the Pt/LSMO interface, resulting in positive magnetoresistance. The interfacial angular-dependent magnetoresistance modulated by the interfacial magnetic states was also observed in the Pt/LSMO (20 nm) heterostructures. Our findings contribute to a broader understanding of interfacial properties between heavy metals and antiferromagnetic manganites.

9.
Int J Med Sci ; 21(7): 1250-1256, 2024.
Article in English | MEDLINE | ID: mdl-38818475

ABSTRACT

Background: Recovery time is a crucial factor in ensuring the safety and effectiveness of both patients and endoscopy centers. Propofol is often preferred due to its fast onset and minimal side effects. Remimazolam is a new intravenous sedative agent, characterized by its rapid onset of action, quick recovery and organ-independent metabolism. Importantly, its effect can be specifically antagonized by flumazenil. The primary goal of this study is to compare the recovery time of remimazolam besylate and propofol anesthesia during endoscopic procedures in elderly patients. Methods: 60 patients aged 65-95 years who underwent gastrointestinal endoscopy were randomly and equally assigned to two groups: the remimazolam group (Group R) and the propofol group (Group P). The primary measure was the recovery time, defined as the time from discontinuing remimazolam or propofol until reaching an Observer's Assessment of Alertness and Sedation scale (OAA/S) score of 5 (responds readily to name spoken in normal tone). The time required to achieve an OAA/S score of 3 (responds after name spoken loudly or repeatedly along with glazed marked ptosis) was also recorded and compared. Results: The recovery time for Group R (2.6 ± 1.6 min) was significantly shorter than that for Group P (10.8 ± 3.0 min), with a 95% confidence interval (CI): 6.949-9.431 min, p <0.001. Similarly, the time to attain an OAA/S score of 3 was significantly less in Group R (1.6 ± 0.9 min) compared to Group P (9.6 ± 2.6 min), with a 95% CI: 6.930-8.957 min, p <0.001. Conclusion: Our study demonstrated that remimazolam anesthesia combined with flumazenil antagonism causes a shorter recovery time for elderly patients undergoing gastrointestinal endoscopy compared to propofol. Remimazolam followed by flumazenil antagonism provides a promising alternative to propofol for geriatric patients, particularly during gastrointestinal endoscopy.


Subject(s)
Anesthesia Recovery Period , Benzodiazepines , Endoscopy, Gastrointestinal , Hypnotics and Sedatives , Propofol , Humans , Aged , Propofol/administration & dosage , Male , Female , Aged, 80 and over , Endoscopy, Gastrointestinal/methods , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/adverse effects , Benzodiazepines/therapeutic use
10.
BMC Nephrol ; 25(1): 125, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38589792

ABSTRACT

BACKGROUND: Sepsis and acute kidney injury (AKI) are common severe diseases in the intensive care unit (ICU). This study aimed to estimate the attributable mortality of AKI among critically ill patients with sepsis and to assess whether AKI was an independent risk factor for 30-day mortality. METHODS: The information we used was derived from a multicenter prospective cohort study conducted in 18 Chinese ICUs, focusing on septic patients post ICU admission. The patients were categorized into two groups: those who developed AKI (AKI group) within seven days following a sepsis diagnosis and those who did not develop AKI (non-AKI group). Using propensity score matching (PSM), patients were matched 1:1 as AKI and non-AKI groups. We then calculated the mortality rate attributable to AKI in septic patients. Furthermore, a survival analysis was conducted comparing the matched AKI and non-AKI septic patients. The primary outcome of interest was the 30-day mortality rate following the diagnosis of sepsis. RESULTS: Out of the 2175 eligible septic patients, 61.7% developed AKI. After the application of PSM, a total of 784 septic patients who developed AKI were matched in a 1:1 ratio with 784 septic patients who did not develop AKI. The overall 30-day attributable mortality of AKI was 6.6% (95% CI 2.3 ∼ 10.9%, p = 0.002). A subgroup analysis revealed that the 30-day attributable mortality rates for stage 1, stage 2, and stage 3 AKI were 0.6% (95% CI -5.9 ∼ 7.2%, p = 0.846), 4.7% (95% CI -3.1 ∼ 12.4%, p = 0.221) and 16.8% (95% CI 8.1 ∼ 25.2%, p < 0.001), respectively. Particularly noteworthy was that stage 3 AKI emerged as an independent risk factor for 30-day mortality, possessing an adjusted hazard ratio of 1.80 (95% CI 1.31 ∼ 2.47, p < 0.001). CONCLUSIONS: The overall 30-day attributable mortality of AKI among critically ill patients with sepsis was 6.6%. Stage 3 AKI had the most significant contribution to 30-day mortality, while stage 1 and stage 2 AKI did not increase excess mortality.


Subject(s)
Acute Kidney Injury , Sepsis , Humans , Retrospective Studies , Prospective Studies , Critical Illness , Acute Kidney Injury/diagnosis , Intensive Care Units , Sepsis/complications
11.
Ecotoxicol Environ Saf ; 281: 116563, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38878560

ABSTRACT

Evodiamine (EVO), the main active alkaloid in Evodia rutaecarpa, was shown to exert various pharmacological activities, especially anti-tumor. Currently, it is considered a potential anti-cancer drug due to its excellent anti-tumor activity, which unfortunately has adverse reactions, such as the risk of liver and kidney injury, when Evodia rutaecarpa containing EVO is used clinically. In the present study, we aim to clarify the potential toxic target organs and toxicity mechanism of EVO, an active monomer in Evodia rutaecarpa, and to develop mitigation strategies for its toxicity mechanism. Transcriptome analysis and related experiments showed that the PI3K/Akt pathway induced by calcium overload was an important step in EVO-induced apoptosis of renal cells. Specifically, intracellular calcium ions were increased, and mitochondrial calcium ions were decreased. In addition, EVO-induced calcium overload was associated with TRPV1 receptor activation. In vivo TRPV1 antagonist and calcium chelator effects were observed to significantly reduce body weight loss and renal damage in mice due to EVO toxicity. The potential nephrotoxicity of EVO was further confirmed by an in vivo test. In conclusion, TRPV1-mediated calcium overload-induced apoptosis is one of the mechanisms contributing to the nephrotoxicity of EVO due to its toxicity, whereas maintaining body calcium homeostasis is an effective measure to reduce toxicity. These studies suggest that the clinical use of EVO-containing herbal medicines should pay due attention to the changes in renal function of patients as well as the off-target effects of the drugs.


Subject(s)
Apoptosis , Calcium , Evodia , Homeostasis , Kidney , Quinazolines , Quinazolines/toxicity , Quinazolines/pharmacology , Animals , Homeostasis/drug effects , Calcium/metabolism , Mice , Apoptosis/drug effects , Kidney/drug effects , Kidney/pathology , Evodia/chemistry , Male , TRPV Cation Channels/metabolism , Calcium Chelating Agents/pharmacology
12.
Molecules ; 29(12)2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38930897

ABSTRACT

This study investigated the mechanism by which fucoxanthin acts as a novel ferroptosis inducer to inhibit tongue cancer. The MTT assay was used to detect the inhibitory effects of fucoxanthin on SCC-25 human tongue squamous carcinoma cells. The levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), and total iron were measured. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to assess glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor 2 (Nrf2), Keap1, solute carrier family 7 member 11 (SLC7A11), transferrin receptor protein 1 (TFR1), p53, and heme oxygenase 1 (HO-1) expression. Molecular docking was performed to validate interactions. Compared with the control group, the activity of fucoxanthin-treated SCC-25 cells significantly decreased in a dose- and time-dependent manner. The levels of MMP, GSH, and SOD significantly decreased in fucoxanthin-treated SCC-25 cells; the levels of ROS, MDA, and total iron significantly increased. mRNA and protein expression levels of Keap1, GPX4, Nrf2, and HO-1 in fucoxanthin-treated cells were significantly decreased, whereas levels of TFR1 and p53 were significantly increased, in a concentration-dependent manner. Molecular docking analysis revealed that binding free energies of fucoxanthin with p53, SLC7A11, GPX4, Nrf2, Keap1, HO-1, and TFR1 were below -5 kcal/mol, primarily based on active site hydrogen bonding. Our findings suggest that fucoxanthin can induce ferroptosis in SCC-25 cells, highlighting its potential as a treatment for tongue cancer.


Subject(s)
Ferroptosis , Heme Oxygenase-1 , Molecular Docking Simulation , NF-E2-Related Factor 2 , Phospholipid Hydroperoxide Glutathione Peroxidase , Xanthophylls , Humans , NF-E2-Related Factor 2/metabolism , Ferroptosis/drug effects , Xanthophylls/pharmacology , Xanthophylls/chemistry , Heme Oxygenase-1/metabolism , Heme Oxygenase-1/genetics , Cell Line, Tumor , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Tongue Neoplasms/drug therapy , Tongue Neoplasms/metabolism , Tongue Neoplasms/pathology , Receptors, Transferrin/metabolism , Membrane Potential, Mitochondrial/drug effects , Kelch-Like ECH-Associated Protein 1/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Amino Acid Transport System y+/metabolism , Amino Acid Transport System y+/genetics , Superoxide Dismutase/metabolism , Down-Regulation/drug effects , Antigens, CD
13.
Pak J Med Sci ; 40(4): 723-729, 2024.
Article in English | MEDLINE | ID: mdl-38544991

ABSTRACT

Objective: To investigate the clinical value of the expression levels of tumor protein D52 (TPD52) and miR-133a on the prognosis assessment of pancreatic cancer surgery. Methods: This was a retrospective study. Ninety-seven patients who underwent radical surgery for pancreatic cancer in Cangzhou Central Hospital from January 2018 to January 2022 were selected and divided into four groups: TPD52 high expression group, TPD52 low expression group, miR-133a high expression group and miR-133a low expression group. The relationship between the expression levels of TPD52 and miR-133a and the clinicopathological features of patients with pancreatic cancer was analyzed. The COX regression model was used to analyze the risk factors affecting the prognosis of patients with pancreatic cancer. Results: The high expression rate of TPD52 and the low expression rate of miR-133a in pancreatic cancer tissues were higher than those in normal paracancerous tissues(P<0.05). Based on the comparison of prognosis and survival, the median survival time of patients with high expression of TPD52 and low expression of miR-133a was lower than that of patients with low expression of TPD52 and high expression of miR-133a, with a statistically significant difference(P<0.05). Moreover, multivariate Cox regression analysis showed that low differentiation of pancreatic cancer, III-IV stage of TNM, high expression of TPD52, as well as low expression of miR-133a were independent risk factors for postoperative survival of patients with pancreatic cancer(P<0.05). Conclusion: TPD52 is expressed at a high level whereas miR-133a at a low level in pancreatic cancer tissues, both of which together with low differentiation of pancreatic cancer and III-IV stage of TNM constitute independent risk factors affecting the surgical prognosis of patients with pancreatic cancer.

14.
Angew Chem Int Ed Engl ; : e202402496, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38863241

ABSTRACT

Promoting the hydrogen oxidation reaction (HOR) activity and poisoning tolerance of electrocatalysts is crucial for the large-scale application of hydrogen-oxygen fuel cell. However, it is severely hindered by the scaling relations among different intermediates. Herein, lattice-contracted Pt-Rh in ultrasmall ternary L12-(Pt0.9Rh0.1)3V intermetallic nanoparticles (~2.2 nm) were fabricated to promote the HOR performances through an oxides self-confined growth strategy. The prepared (Pt0.9Rh0.1)3V displayed 5.5/3.7 times promotion in HOR mass/specific activity than Pt/C in pure H2 and dramatically limited activity attenuation in 1000 ppm CO/H2 mixture. In-situ Raman spectra tracked the superior anti-CO* capability as a result of compressive strained Pt, and the adsorption of oxygen-containing species was promoted due to the dual-functional effect. Further assisted by density functional theory calculations, both the adsorption of H* and CO* on (Pt0.9Rh0.1)3V were reduced compared with that of Pt due to lattice contraction, while the adsorption of OH* was enhanced by introducing oxyphilic Rh sites. This work provides an effective tactic to stimulate the electrocatalytic performances by optimizing the adsorption of different intermediates severally.

15.
Exp Eye Res ; 230: 109465, 2023 05.
Article in English | MEDLINE | ID: mdl-37030582

ABSTRACT

Vitreomacular traction syndrome results from persistent vitreoretinal adhesions in the setting of partial posterior vitreous detachment (PVD). Vitrectomy and reattachment of retina is an effective therapeutic approach. The adhesion between vitreous cortex and internal limiting membrane (ILM) of the retina is stronger in youth, which brings difficulties to induce PVD in vitrectomy. Several clinical investigations demonstrated that intravitreous injection of plasmin before vitrectomy could reduce the risk of detachment. In our study, a novel recombinant human microplasminogen (rhµPlg) was expressed by Pichia pastoris. Molecular docking showed that the binding of rhµPlg with tissue plasminogen activator (t-PA) was similar to plasminogen, suggesting rh µPlg could be activated by t-PA to generate microplasmin (µPlm). Moreover, rhµPlg had higher catalytic activity than plasminogen in amidolytic assays. Complete PVD was found at vitreous posterior pole of 125 µg rhµPlg-treated eyes without morphological change of retina in juvenile rabbits via intraocular injection. Our results demonstrate that rhµPlg has a potential value in the treatment of vitreoretinopathy.


Subject(s)
Retinal Diseases , Vitreous Detachment , Animals , Humans , Rabbits , Adolescent , Vitreous Detachment/drug therapy , Tissue Plasminogen Activator/metabolism , Tissue Plasminogen Activator/pharmacology , Vitreous Body/metabolism , Molecular Docking Simulation , Retina , Vitrectomy/methods , Plasminogen/metabolism , Plasminogen/pharmacology , Injections, Intraocular , Retinal Diseases/metabolism , Serine Proteases
16.
Langmuir ; 39(36): 12707-12714, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37653708

ABSTRACT

In nature, selective chiral interactions between biomolecules and minerals provide insight into the mysterious origin of homochirality. Here, we show growing gypsum crystals in a nonequilibrium state can recognize chiral enantiomers of amino acids. The chiral selection for amino acids with different functional groups by growing minerals are distinct. For 11 amino acids, the d-isomer slows dynamic gypsum growth more than the l-isomer, whereas for another 7 amino acids, the opposite was observed. These differences in chiral recognition are attributed to the different stereochemical matching between the chiral amino acids and the dynamic steps of growing gypsum. These stereoselective interactions between amino acid enantiomers and dynamic growing crystals can be applied toward the fabrication of gypsum cements to regulate their structure and mechanical properties. These findings provide insight into understanding the mechanism of the origin of homochirality in nature and suggest a pathway for constructing advanced functional materials.

17.
Br J Clin Pharmacol ; 89(6): 1799-1808, 2023 06.
Article in English | MEDLINE | ID: mdl-36527308

ABSTRACT

AIMS: Dexmedetomidine could be an ideal adjuvant to propofol during gastrointestinal endoscopy because it provides both analgesia and sedation without respiratory depression. This study investigates the effect of different doses of dexmedetomidine on the median effective concentration of propofol during gastrointestinal endoscopy. METHODS: Ninety adult patients were randomly assigned to Group Control, Group DEX0.5 (0.5 µg/kg dexmedetomidine) or Group DEX1.0 (1.0 µg/kg dexmedetomidine). Anaesthesia during endoscopy was implemented by plasma target-controlled infusion (TCI) of propofol with different doses of dexmedetomidine. TCI concentration of the first patient for each group was 2.5 µg/mL and the consecutive adjacent concentration gradient was 0.5 µg/mL. Median effective concentration (EC50 ) of propofol by TCI for gastrointestinal endoscopy was determined by using the modified Dixon's up-and-down method. Cardiovascular variables were also measured. RESULTS: EC50 of propofol by TCI and 95% confidence interval (CI) for gastrointestinal endoscopy were 3.77 (3.48-4.09), 2.51 (2.27-2.78) and 2.10 (1.90-2.33) µg/mL in Group Control, Group DEX0.5 and Group DEX1.0, respectively. The average percent change from heart rate (HR) baseline was 2.8 (8.9), -7.4 (7.7) and -10.5 (8.8) (P < .001), and the average percent change from mean arterial pressure (MAP) baseline was -10.6 [-24.7; 3.5], -9.5 [-29.2; 11.4] and -4.0 [-27.3; 15.5] (P = .034) in Group Control, Group DEX0.5 and Group DEX1.0, respectively. CONCLUSIONS: Dexmedetomidine reduced the EC50 of propofol by TCI. A 0.5-1 µg/kg dose of dexmedetomidine caused a decrease in HR without bradycardia. The decrease in dosage of propofol with increasing doses of dexmedetomidine caused more stable MAP. Dexmedetomidine is an ideal adjuvant drug to propofol during gastrointestinal endoscopy.


Subject(s)
Anesthesia , Dexmedetomidine , Propofol , Adult , Humans , Hypnotics and Sedatives , Endoscopy, Gastrointestinal
18.
Environ Sci Technol ; 57(37): 13991-14001, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37523249

ABSTRACT

Coprecipitation of Fe/Cr hydroxides with natural organic matter (NOM) is an important pathway for Cr immobilization. However, the role of NOM in coprecipitation is still controversial due to its molecular heterogeneity and diversity. This study focused on the molecular selectivity of NOM toward Fe/Cr coprecipitates to uncover the fate of Cr via Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS). The results showed that the significant effects of Suwannee River NOM (SRNOM) on Cr immobilization and stability of the Fe/Cr coprecipitates did not merely depend on the adsorption of SRNOM on Fe/Cr hydroxides. FT-ICR-MS spectra suggested that two pathways of molecular selectivity of SRNOM in the coprecipitation affected Cr immobilization. Polycyclic aromatics and polyphenolic compounds in SRNOM preferentially adsorbed on the Fe/Cr hydroxide nanoparticles, which provided extra binding sites and promoted the aggregation. Notably, some specific compounds (i.e., polyphenolic compounds and highly unsaturated phenolic compounds), less unsaturated and more oxygenated than those adsorbed on Fe/Cr hydroxide nanoparticles, were preferentially incorporated into the insoluble Cr-organic complexes in the coprecipitates. Kendrick mass defect analysis revealed that the insoluble Cr-organic complexes contained fewer carbonylated homologous compounds. More importantly, the spatial distribution of insoluble Cr-organic complexes was strongly related to Cr immobilization and stability of the Fe/Cr-NOM coprecipitates. The molecular information of the Fe/Cr-NOM coprecipitates would be beneficial for a better understanding of the transport and fate of Cr and exploration of the related remediation strategy.


Subject(s)
Nanoparticles , Phenols , Mass Spectrometry , Nanoparticles/chemistry , Adsorption
19.
Cell Mol Biol (Noisy-le-grand) ; 69(10): 155-159, 2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37953572

ABSTRACT

Insulin-like growth factor 1 (IGF-1) has been reported to potentially link with childhood obesity and obesity-related asthma, although a causal effect has not been illustrated. This study aimed to assess their association via multi-variable Mendelian randomization (MR) analysis with two-sample summary-level data on genetic variants as instrumental variables, thus estimating a causal effect. Genetic variants associated with serum IGF-1 at genome-wide significance (GWS) in the UK Biobank study involving 363,228 individuals of European descent were introduced as instrumental variables. Summary-level data on childhood obesity and obesity-related asthma were obtained from genome-wide association studies (GWAS). Here, MR-Egger, inverse-variance weighted (IVW), simple median, weighted median and penalized weighted median methods were used in the MR study. Results showed that there were strong causal associations of IGF-1 with childhood obesity (OR, 1.27; 95% CI 1.01-1.60; P<0.05) and obesity-related asthma (OR, 1.22; 95% CI 1.07-1.38; P<0.005). In conclusion, A causal association between high IGF-1 levels and high risks of childhood obesity and obesity-related asthma is estimated, which requires further validation in large-scale trials.


Subject(s)
Asthma , Pediatric Obesity , Child , Humans , Pediatric Obesity/epidemiology , Pediatric Obesity/genetics , Insulin-Like Growth Factor I/genetics , Genome-Wide Association Study , Mendelian Randomization Analysis , Asthma/epidemiology , Asthma/genetics , Polymorphism, Single Nucleotide
20.
Philos Trans A Math Phys Eng Sci ; 381(2260): 20220386, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37742712

ABSTRACT

Additive manufacturing (AM) has attracted many attentions because of its design freedom and rapid manufacturing; however, it is still limited in actual application due to the existing defects. In particular, various defect features have been proved to affect the fatigue performance of components and lead to fatigue scatter. In order to properly assess the influences of these defect features, a defect driven physics-informed neural network (PiNN) is developed. By embedding the critical defects information into loss functions, the defect driven PiNN is enhanced to capture physical information during training progress. The results of fatigue life prediction for different AM materials show that the proposed PiNN effectively improves the generalization ability under small samples condition. Compared with the fracture mechanics-based PiNN, the proposed PiNN provides physically consistent and higher accuracy without depending on the choice of fracture mechanics-based model. Moreover, this work provides a scalable framework being able to integrate more prior knowledge into the proposed PiNN. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.

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