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1.
Nucleic Acids Res ; 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39142658

ABSTRACT

Visualizing and measuring molecular-scale interactions in living cells represents a major challenge, but recent advances in single-molecule super-resolution microscopy are bringing us closer to achieving this goal. Single-molecule super-resolution microscopy enables high-resolution and sensitive imaging of the positions and movement of molecules in living cells. HP1 proteins are important regulators of gene expression because they selectively bind and recognize H3K9 methylated (H3K9me) histones to form heterochromatin-associated protein complexes that silence gene expression, but several important mechanistic details of this process remain unexplored. Here, we extended live-cell single-molecule tracking studies in fission yeast to determine how HP1 proteins interact with their binding partners in the nucleus. We measured how genetic perturbations that affect H3K9me alter the diffusive properties of HP1 proteins and their binding partners, and we inferred their most likely interaction sites. Our results demonstrate that H3K9 methylation spatially restricts HP1 proteins and their interactors, thereby promoting ternary complex formation on chromatin while simultaneously suppressing off-chromatin binding. As opposed to being an inert platform to direct HP1 binding, our studies propose a novel function for H3K9me in promoting ternary complex formation by enhancing the specificity and stimulating the assembly of HP1-protein complexes in living cells.


Visualizing molecular-scale interactions in living cells is challenging, but advances in single-molecule super-resolution microscopy enable high-resolution imaging of molecular positions of proteins and their motions within cells. HP1 proteins bind to H3K9 methylated histones to form complexes that silence gene expression. Here, we tracked single HP1 proteins and their binding partners to measure when and where they form complexes in live fission yeast cells. Genetic perturbations enabled us to connect their motions to specific changes in their cellular properties. Surprisingly, we noted that HP1 proteins preferentially form ternary complexes with their binding partners at sites of H3K9me. This work proposes a novel function for chromatin and shows how H3K9 methylation spatially restricts HP1-associated complex formation while suppressing off-chromatin binding.

2.
Nano Lett ; 24(19): 5831-5837, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38708822

ABSTRACT

Single lanthanide (Ln) ion doped upconversion nanoparticles (UCNPs) exhibit great potential for biomolecule sensing and counting. Plasmonic structures can improve the emission efficiency of single UCNPs by modulating the energy transferring process. Yet, achieving robust and large-area single UCNP emission modulation remains a challenge, which obstructs investigation and application of single UCNPs. Here, we present a strategy using metal nanohole arrays (NHAs) to achieve energy-transfer modulation on single UCNPs simultaneously within large-area plasmonic structures. By coupling surface plasmon polaritons (SPPs) with higher-intermediate state (1D2 → 3F3, 1D2 → 3H4) transitions, we achieved a remarkable up to 10-fold enhancement in 800 nm emission, surpassing the conventional approach of coupling SPPs with an intermediate ground state (3H4 → 3H6). We numerically simulate the electrical field distribution and reveal that luminescent enhancement is robust and insensitive to the exact location of particles. It is anticipated that the strategy provides a platform for widely exploring applications in single-particle quantitative biosensing.

3.
J Transl Med ; 22(1): 427, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38711144

ABSTRACT

BACKGROUND: Circular RNAs (circRNAs), one of the major contents of exosomes, have been shown to participate in the occurrence and progression of cancers. The role and the diagnostic potential of exosome-transported circRNAs in non-small-cell lung cancer (NSCLC) remain largely unknown. METHODS: The NSCLC-associated exosomal circ_0061407 and circ_0008103 were screened by circRNA microarray. The role of circ_0061407 and circ_0008103 in NSCLC was examined in vitro and in vivo. The encapsulation of the two circRNAs into exosomes and the transport to recipient cells were observed by confocal microscopy. The effects of exosome-transported circ_0061407 and circ_0008103 on recipient cells were investigated using a co-culture device. Bioinformatics analyses were performed to predict the mechanisms by which circ_0061407 and circ_0008103 affected NSCLC. The quantitative polymerase chain reaction was used to quantify the exosome-containing circ_0061407 and circ_0008103 in the serum samples of healthy, pneumonia, benign lung tumours, and NSCLC. The diagnostic efficacy was evaluated using receiver operating characteristic curves. RESULTS: The levels of circ_0061407 and circ_0008103 within exosomes were down-regulated in the serum of patients with NSCLC. The up-regulation of circ_0061407 and circ_0008103 inhibited the proliferation, migration/invasion, cloning formation of NSCLC cells in vitro and inhibited lung tumour growth in vivo. Circ_0061407 and circ_0008103 were observed to be packaged in exosomes and transported to recipient cells, where they inhibited the proliferation, migration/invasion, and cloning formation abilities of the recipient cells. Moreover, circ_0061407 and circ_0008103 might be involved in the progression of NSCLC by interacting with microRNAs and proteins. Additionally, lower serum exosomal circ_0061407 and circ_0008103 levels were associated with advanced pathological staging and distant metastasis. CONCLUSIONS: This study identified two novel exosome-transported circRNAs (circ_0061407 and circ_0008103) associated with NSCLC. These findings may provide additional insights into the development of NSCLC and potential diagnostic biomarkers for NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Exosomes , Lung Neoplasms , RNA, Circular , Exosomes/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/blood , RNA, Circular/genetics , RNA, Circular/blood , RNA, Circular/metabolism , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/blood , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Male , Gene Expression Regulation, Neoplastic , Female , Mice, Nude , Middle Aged , Mice, Inbred BALB C , ROC Curve , Mice
4.
Clin Gerontol ; : 1-14, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38367001

ABSTRACT

OBJECTIVES: COVID-19 escalated stress within family/neighborhood (local) and national/cultural (global) levels. However, the impact of socioecological levels of stress on pandemic emotion regulation remains largely unexplored. METHODS: Thirty older adults from the Northeast US (63-92 years) reported on pandemic stress and emotion regulation in semi-structured interviews. Responses were coded into socioecological sources of local and global stress, and associated use of cognitive emotion regulation strategies from the Cognitive Emotion Regulation Questionnaire was explored. RESULTS: Older adults experienced significant distress at global levels, and perception of lacking top-down safety governance may have exacerbated local distress of engaging in daily activities during the COVID-19 pandemic. Participants endorsed coping with local stressors via perspective-taking, acceptance, and other adaptive strategies, while global sources of stress were associated with greater use of maladaptive strategies, including other-blame and rumination. CONCLUSION: Quantitative assessments may underestimate significant older adult distress and maladaptive coping toward global stressors. Findings should be replicated with more diverse populations beyond the COVID-19 context.

5.
Am J Forensic Med Pathol ; 44(2): 111-115, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36689553

ABSTRACT

ABSTRACT: Pulmonary thromboembolism (PTE) is a common cause of sudden unexpected death in forensic and clinical practice. Although the prevention of thrombosis has been paid more attention in clinical practice in recent years, the number of deaths due to PTE remains extensive. In the present study, 145 cases of fatal PTE were collected and retrospectively analyzed from 2001 to 2020 at the School of Forensic Medicine, China Medical University in Liaoning Province, northeast of China. The demographic characteristics, risk factors of PTE, origins of thrombi, and time interval from the occurrence of main risk factors to PTE were retrospectively analyzed. The 40 to 59 age group accounted for the 51.0% of the total cases. Immobilization, trauma (especially fracture of the pelvis, femur, tibia, or fibula), surgery, cesarean section, and mental disorders were the top 5 high-risk factors. Among the involved cases, 92.9% of the PTE (130/140) occurred within 60 days and peak at 8 to 15 days after the exposure of main risk factors. According to the autopsy findings, 87.6% of the thrombi blocked the bilateral pulmonary arteries at pulmonary hilus, with a maximum diameter of 1.6 cm and a maximum length of 21.9 cm, which were mainly derived from lower limb (65.5%) or pelvic veins (10.3%). Although the embolus limited the pulmonary circulation, there is no difference on the ratio of lung-to-heart weight between PTE and the disease-free accident victims. Overall, our present retrospective study provides important information for the forensic analysis on the cause of death and potential guidance on clinical prevention of PTE.


Subject(s)
Cesarean Section , Pulmonary Embolism , Pregnancy , Humans , Female , Retrospective Studies , Cesarean Section/adverse effects , Pulmonary Embolism/pathology , Forensic Pathology , Forensic Medicine , Death, Sudden/etiology
6.
J Esthet Restor Dent ; 35(7): 1131-1138, 2023 10.
Article in English | MEDLINE | ID: mdl-37078417

ABSTRACT

OBJECTIVE: The purpose of this study was to compare the clinical outcomes of vestibular incision subperiosteal tunnel technique (VISTA) and tunnel approach combined with connective tissue graft (CTG) for treatment of type 1 (RT1) multiple gingival recession. MATERIALS AND METHODS: Twenty-four patients with a total of 59 nonmolar recession teeth were randomly allocated to VISTA + CTG or Tunnel + CTG group. Recession depth and width, probing depth, clinical attachment level, width of keratinized tissue, gingival thickness, flap tension, mean root coverage (MRC), complete root coverage (CRC), patient-centered, and esthetic outcomes (root coverage esthetic scores, RES) were assessed at baseline and 12 months after surgery. RESULTS: At 12 months, MRC of 91.13 ± 16.96% and 91.40 ± 13.53%, CRC of 70.97% and 67.86% were observed for VISTA + CTG and Tunnel + CTG group respectively, with no significant difference between the two groups (p > 0.05). High RES of 8.52 ± 1.46 and 8.82 ± 1.44 was obtained in VISTA + CTG and Tunnel + CTG group respectively, without showing a significant difference (p = 0.245), while less scar formation was observed in Tunnel + CTG group (p < 0.01). CONCLUSIONS: Both procedures were effective for root coverage in RT1 multiple gingival recession at 12 months. Better esthetic result with less scar formation was obtained in tunnel approach combined with CTG without vestibular incision. (Registration number: ChiCTR-INR-16007845, registered on 19/12/2015, http://www.chictr.org.cn). CLINICAL SIGNIFICANCE: VISTA + CTG and Tunnel + CTG were both effective for root coverage in RT1 multiple gingival recession, with satisfying esthetic outcomes. However, it is suggested in critical esthetic areas, treatment options of making vertical incisions should be carefully considered.


Subject(s)
Gingival Recession , Humans , Gingival Recession/surgery , Treatment Outcome , Cicatrix , Tooth Root , Gingiva/surgery
7.
Fam Process ; : e12909, 2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37382401

ABSTRACT

This study examined the reciprocal prospective associations between commitment, forgiveness, and different aspects of marital well-being (marital satisfaction and marital instability) among Chinese newlywed couples and the gender differences in these associations. The Vulnerability-Stress-Adaptation (VSA) model posits reciprocal associations between adaptive processes and relationship satisfaction. However, the directionality of the associations between adaptive processes and marital satisfaction may differ from the associations between adaptive processes and marital instability in Chinese societies due to the emphasis on relationship maintenance. Based on three annual waves of data from 268 Chinese newlywed couples (Mage = 29.59, SD = 3.25 for husbands; Mage = 28.08, SD = 2.51 for wives), a cross-lagged approach was used to examine the reciprocal associations between commitment, forgiveness, and marital satisfaction/instability. We found: (a) reciprocal associations between commitment/forgiveness and marital satisfaction (wives only); (b) reciprocal associations between forgiveness and marital instability (husbands only); and (c) wives' commitment at Wave 2 mediated the association between wives' commitment at Wave 1 and wives' marital satisfaction at Wave 3. Extending the VSA model, findings suggest different reciprocal associations between commitment, forgiveness, and different aspects of marital well-being among Chinese newlywed couples. Results highlight the important role of culture and gender in marital relationships and clinical practice.

8.
Fam Process ; : e12898, 2023 May 28.
Article in English | MEDLINE | ID: mdl-37246354

ABSTRACT

Based on three annual waves of data from 268 Chinese newlyweds (Mage = 29.59, SD = 3.25 for husbands; Mage = 28.08, SD = 2.51 for wives), the present study examined the bidirectional associations between external stressors, perceived spousal support, and marital instability by using a three-wave, cross-lagged approach. Results indicated bidirectional associations between external stressors and marital instability, and a unidirectional association linking marital instability to perceived spousal support. Additionally, external stressors at Wave 2 mediated the association between external stressors at Wave 1 and marital instability at Wave 3. Taken together, the present study contributes to an emerging body of research aimed at clarifying: (a) the directionality of the associations between external stressors, perceived spousal support, and marital instability; (b) how external stressors cumulatively affect the development of marital instability. Our study extends the Vulnerability-Stress-Adaptation (VSA) model and has developmental implications for promoting marital relationships in non-Western couples.

9.
BMC Oral Health ; 23(1): 298, 2023 05 16.
Article in English | MEDLINE | ID: mdl-37194034

ABSTRACT

BACKGROUND: Few studies have evaluated the effects of the crown-to-implant (C/I) ratio on the marginal bone level (MBL) and bone density in non-splinted single implants. The aim of this study was to assess the effect of C/I ratio on MBL and density of peri-implant bone in non-splinted posterior implants. METHODS: The C/I ratio, MBL, and grayscale values (GSVs) for bone density were measured from X-rays. Four areas of interest (two at the apical area and two at the middle of the peri-implant area) and two control areas were selected for evaluation. Follow-up radiographs were calibrated according to the control areas. RESULTS: In all, 117 non-splinted posterior implants in 73 patients followed up for a mean duration of 36.23 ± 10.40 (range 24-72) months were considered. The mean anatomical C/I ratio was 1.78 ± 0.43 (range 0.93 to 3.06). The mean change in MBL was 0.28 ± 0.97 mm. There were no significant associations between the C/I ratio and MBL changes (r = -0.028, p = 0.766). Pearson correlation showed a significant correlation between changes in GSV and the C/I ratio in the middle peri-implant area (r = 0.301, p = 0.001) and apical area (r = 0.247, p = 0.009). CONCLUSIONS: A higher C/I ratio of single non-splinted posterior implants is associated with increased peri-implant bone density, but not correlated with changes in MBL.


Subject(s)
Alveolar Bone Loss , Dental Implants , Humans , Bone Density , Cross-Sectional Studies , Alveolar Bone Loss/diagnostic imaging , Crowns , Follow-Up Studies , Dental Prosthesis, Implant-Supported , Dental Prosthesis Design
10.
Angew Chem Int Ed Engl ; 62(46): e202312231, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37750462

ABSTRACT

The use of dopant-free hole transport layers (HTLs) is critical in stabilizing n-i-p perovskite solar cells (pero-SCs). However, these HTL materials are often processed with toxic solvents, which is not ideal for industrial production. Upon substituting them with green solvents, a trade-off emerges between maintaining the high crystallinity of the HTL materials and ensuring high solubility in the new solvents. In this paper, we designed a novel, linear, organic small molecule, BDT-C8-3O, by introducing an asymmetric polar oligo(ethylene glycol) side chain. This method not only overcomes the solubility limitations in green solvents but also enables stacking the conjugated main chains in two patterns, which further enhances crystallinity and hole mobility. As a result, the n-i-p pero-SCs based on chlorobenzene- or green (natural compound) solvent 3-methylcyclohexanone-processed BDT-C8-3O HTL that without any dopant delivered world-recorded power conversion efficiencies of 24.11 % (certified of 23.82 %) and 23.53 %, respectively. The devices also demonstrated remarkable operational and high-temperature stabilities, maintaining over 84 % and 79.5 % of their initial efficiency for 2000 h, respectively. Encouragingly, dopant-free BDT-C8-3O HTL exhibits significant advantages in large-area fabrication, achieving state-of-the-art PCEs exceeding 20 % for 5×5 cm2 modules (active area: 15.64 cm2 ), even when processed using green solvents.

11.
BMC Cancer ; 22(1): 61, 2022 Jan 13.
Article in English | MEDLINE | ID: mdl-35027040

ABSTRACT

BACKGROUND: To observe the clinicopathological and prognostic value of long non-coding RNA five prime to X inactive specific transcript (lncFTX) in multiple tumors. METHODS: Eligible studies for lncFTX were identified by searching PubMed, Embase, Web of Science and Cochrane Library databases from inception to December 01, 2020. Stata 12.0 software was used to calculate the odds ratio (OR)/hazard ratio (HR) and 95% confidence interval (95% CI). We used The Cancer Genome Atlas (TCGA) dataset to further investigate the differential expression and prognostic value of lncFTX. RESULTS: We included 11 studies involving a total of 1633 patients. The results showed that the expression of lncFTX was positively associated with advanced TNM stage (III-IV versus I-II) (OR = 2.30, 95% CI: 1.74-3.03, P < 0.05), lymph nodes metastasis (OR = 3.01, 95% CI: 2.00-4.52, P < 0.05), distant metastasis (OR = 3.68, 95% CI: 2.13-6.34, P < 0.05), and cancer mortality (HR = 1.83, 95% CI: 1.20-2.81, P < 0.05). However, the expression of lncFTX was not associated with tumor differentiation (poor differentiation versus well or moderate differentiation) and vessel invasion of cancer. Subgroup analysis showed that the higher lncFTX expression was associated with shorter overall survival in cancer patients, regardless of the sample size and cancer type. No publication bias was found, and the sensitivity analysis results suggested that the main findings were robust. Elevated expression and prognostic significance of FTX were confirmed using TCGA dataset. CONCLUSIONS: This study found that the expression of lncFTX was positively associated with advanced tumor node metastasis (TNM) stage, lymph nodes, distant metastasis and, cancer mortality, suggesting that lncFTX might be a potential prognostic biomarker for tumors.


Subject(s)
Neoplasms , RNA, Long Noncoding , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Female , Humans , Lymphatic Metastasis , Male , Neoplasms/diagnosis , Neoplasms/genetics , Neoplasms/mortality , Neoplasms/pathology , Prognosis , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
12.
Res Sports Med ; 30(5): 540-553, 2022.
Article in English | MEDLINE | ID: mdl-33870810

ABSTRACT

This study assessed the associations of maximal isometric strength and movement economy in 126 recreationally active men and women. Oxygen consumption was assessed through a graded treadmill test with 4-minute increments (4-12 km∙h-1). Maximal isometric leg extensor, leg flexor and handgrip strength were assessed by isometric dynamometry. Models of best fit for gross oxygen cost and gross caloric unit cost were observed across the majority of velocities when the leg extensor/flexor strength ratio and handgrip strength were combined (R2 = 0.207-0.525 and R2 = 0.152-0.475, respectively). Additionally, the oxygen cost differed statistically for the majority of velocities when participants were split by the median of leg extensor strength (12.3-26.3 ml∙kg-1∙km-1, p < 0.05) and the average of all strength variables (13.9-30.3 ml∙kg-1∙km-1, p < 0.05). Our data underline the importance of maintaining maximal strength in order to perform activities with low to moderate oxygen demands.


Subject(s)
Oxygen , Running , Female , Hand Strength , Humans , Male , Muscle Strength , Muscle, Skeletal , Oxygen Consumption , Walking
13.
Angew Chem Int Ed Engl ; 61(42): e202210613, 2022 Oct 17.
Article in English | MEDLINE | ID: mdl-36064999

ABSTRACT

Dopant-free organic hole transport materials (HTMs) remain highly desirable for stable and efficient n-i-p perovskite solar cells (pero-SCs) but rarely succeed. Here, we propose a molecular assembly strategy to overcome the limited optoelectronic properties of organic HTMs by precisely designing a linear organic small molecule BDT-DPA-F from the atomic to the molecular levels. BDT-DPA-F can assemble into a fibril network, showing an obviously improved hole mobility and decreased energy disorder. The resultant pero-SCs showed a promising efficiency of 23.12 % (certified 22.48 %), which is the highest certified value of pero-SCs with dopant-free HTMs, to date. These devices also showed a weak-dependence of efficiency on size, enabling a state-of-the-art efficiency of 22.50 % for 1-cm2 device and 20.17 % for 15.64-cm2 module. For the first time, the pero-SCs based on dopant-free HTMs realized ultralong stabilities with T80 lifetimes over 1200 h under operation or thermal aging at 85 °C.

14.
Phys Rev Lett ; 127(18): 187004, 2021 Oct 29.
Article in English | MEDLINE | ID: mdl-34767411

ABSTRACT

The superconductivity of a kagome superconductor CsV_{3}Sb_{5} is studied by scanning tunneling microscopy and spectroscopy at ultralow temperature with high resolution. Two kinds of superconducting gaps with multiple sets of coherent peaks and residual zero-energy density of states (DOS) are observed on both half-Cs and Sb surfaces, implying multiband superconductivity. In addition, in-gap states can be induced by magnetic impurities but not by nonmagnetic impurities, suggesting a sign-preserving or s-wave superconducting order parameter. Moreover, the interplay between charge density waves (CDW) and superconductivity differs on various bands, resulting in different density-of-states distributions. Our results suggest that the superconducting gap is likely isotropic on the sections of Fermi surface that play little roles in CDW, and the superconducting gaps on the sections of Fermi surface with anisotropic CDW gaps are likely anisotropic as well. The residual spectral weights at zero energy are attributed to the extremely small superconducting gap on the tiny oval Fermi pockets. Our study provides critical clues for further understanding the superconductivity and its relation to CDW in CsV_{3}Sb_{5}.

15.
Am J Forensic Med Pathol ; 42(1): 88-91, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33186129

ABSTRACT

ABSTRACT: Ovarian hyperstimulation syndrome (OHSS) is a rare iatrogenic disorder associated with controlled ovarian stimulation during assisted reproductive technology. Severe OHSS may impose serious complications, including pleural effusion, acute renal insufficiency, venous thrombosis, and even death, although lethal outcomes are rare in forensic practice. The reported incidence of severe OHSS ranges from 0.008% to 10%. Herein, we present the case of a 29-year-old woman who diagnosed with polycystic ovary syndrome and infertility chose to undergo assisted reproduction. She received leuprorelin acetate and follicle stimulating hormone prior to egg retrieval. Three days after the retrieval procedure, she developed abdominal pain and distension. Later that same day, she died unexpectedly. The subsequent autopsy revealed turbid effusions of pleural and peritoneal cavities, abnormal ovarian enlargement, and duskiness of multiple organ surfaces. Microscopic examination disclosed edema and hemorrhage in follicles of both ovaries, thrombosis within the myocardial matrix, and massive pulmonary edema. Routine toxicology screening was negative. The death was attributed to severe OHSS. This case provides a morphologic reference for clinical and forensic work. Autopsy findings in instances of severe OHSS provide valuable insight into the mechanisms and pathogenesis of this disease.


Subject(s)
Death, Sudden/etiology , Ovarian Hyperstimulation Syndrome/complications , Adult , Female , Humans , Oocyte Retrieval , Reproductive Techniques, Assisted/adverse effects
16.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1070-1075, 2020 Mar.
Article in Zh | MEDLINE | ID: mdl-32237448

ABSTRACT

The application of traditional Chinese medicine(TCM) formula granules in clinical practice is gradually extensive. However, TCM formula granules is still lacking rapid and simple quality control standards. In this study, allele-specific PCR and enzyme-linked immunoassay(ELISA) was used for rapid detection of the quality of Lonicerae Japonicae Flos formula granules. The authenticity of Lonicerae Japonicae Flos formula granules was identified by allele-specific PCR and index component was detected by ELISA. Thus, it lays a foundation for the establishment of rapid quality detection standard for Lonicerae Japonicae Flos formula granules, and also provides reference for other studies on the quality standard of traditional Chinese medicine formula granules.


Subject(s)
Drugs, Chinese Herbal/analysis , Lonicera/chemistry , Chromatography, High Pressure Liquid , Enzyme-Linked Immunosorbent Assay , Medicine, Chinese Traditional , Polymerase Chain Reaction , Quality Control
17.
Angew Chem Int Ed Engl ; 59(34): 14434-14442, 2020 Aug 17.
Article in English | MEDLINE | ID: mdl-32259391

ABSTRACT

It is of pivotal importance to develop efficient catalysts and investigate the intrinsic mechanism for CO2 methanation. Now, it is reported that PdFe intermetallic nanocrystals afforded high activity and stability for CO2 methanation. The mass activity of fct-PdFe nanocrystals reached 5.3 mmol g-1 h-1 , under 1 bar (CO2 :H2 =1:4) at 180 °C, being 6.6, 1.6, 3.3, and 5.3 times as high as that of fcc-PdFe nanocrystals, Ru/C, Ni/C, and Pd/C, respectively. After 20 rounds of successive reaction, 98 % of the original activity was retained for PdFe intermetallic nanocrystals. Further mechanistic studies revealed that PdFe intermetallic nanocrystals enabled the maintenance of metallic Fe species via a reversible oxidation-reduction process in CO2 methanation. The metallic Fe in PdFe intermetallic nanocrystals induced the direct conversion of CO2 into CO* as the intermediate, contributing to the enhanced activity.

18.
Biophys J ; 116(4): 684-693, 2019 02 19.
Article in English | MEDLINE | ID: mdl-30686488

ABSTRACT

The replisome is a multiprotein machine responsible for the faithful replication of chromosomal and plasmid DNA. Using single-molecule super-resolution imaging, we characterized the dynamics of three replisomal proteins in live Bacillus subtilis cells: the two replicative DNA polymerases, PolC and DnaE, and a processivity clamp loader subunit, DnaX. We quantified the protein mobility and dwell times during normal replication and following replication fork stress using damage-independent and damage-dependent conditions. With these results, we report the dynamic and cooperative process of DNA replication based on changes in the measured diffusion coefficients and dwell times. These experiments show that the replication proteins are all highly dynamic and that the exchange rate depends on whether DNA synthesis is active or arrested. Our results also suggest coupling between PolC and DnaX in the DNA replication process and indicate that DnaX provides an important role in synthesis during repair. Furthermore, our results suggest that DnaE provides a limited contribution to chromosomal replication and repair in vivo.


Subject(s)
Bacterial Proteins/metabolism , DNA Polymerase III/metabolism , DNA Replication , DNA-Directed DNA Polymerase/metabolism , Bacillus subtilis/enzymology , Bacillus subtilis/genetics , DNA Damage
19.
BMC Neurol ; 18(1): 61, 2018 May 03.
Article in English | MEDLINE | ID: mdl-29724190

ABSTRACT

BACKGROUND: Epilepsy is a major complication of stroke. We aimed to establish whether there is an association between intravenous thrombolysis, intra-arterial thrombolysis and post stroke seizure (PSS) development. Improved understanding of the relationship between reperfusion therapies and seizure development may improve post-stroke monitoring and follow-up. METHODS: This was a retrospective, multicentre cohort study conducted at the Royal Melbourne Hospital and Jingling Hospital Nanjing. We included patients with anterior circulation ischemic stroke admitted 2008-2015. Patients were divided into four treatment groups 1. IV-tPA only, 2. Intra-arterial therapies (IAT) only, 3. IAT + IV-tPA and 4. stroke unit care only (i.e. no IV-tPA or IAT). To assess the association between type of reperfusion treatment and seizure incidence we used multivariable logistic regression models adjusted for age, stroke severity, 3-month functional outcome and prognostic factors. RESULTS: There were 1375 stroke unit care-only patients, of whom 28 (2%) developed PSS. There were 363 patients who received only IV-tPA, of whom 21 (5.8%) developed PSS. There were 93 patients who received IAT only, of whom 12 (12.9%) developed PSS and 112 that received both IV-tPA + IAT, of which 5 (4.5%) developed PSS. All reperfusion treatments were associated with seizure development compared to stroke unit care-only patients: IV-tPA only adjusted odds ratio (aOR) 3.7, 95%CI 1.8-7.4, p < 0.0001; IAT aOR 5.5, 95%CI 2.1-14.3, p < 0.0001, IAT + IV-tPA aOR 3.4, 95% CI 0.98-11.8, p = 0.05. These aORs did not differ significantly between treatment groups (IV-tPA + IAT versus IV-tPA p = 0.89, IV-tPA + IAT versus IAT, p = 0.44). CONCLUSIONS: Patients receiving thrombolytic or intra-arterial reperfusion therapies for acute ischemic stroke are at higher risk of epilepsy and may benefit from longer follow-up. No evidence for an additive or synergistic effect of treatment modality on seizure development was found.


Subject(s)
Fibrinolytic Agents/adverse effects , Seizures/etiology , Stroke/therapy , Thrombectomy/adverse effects , Thrombolytic Therapy/adverse effects , Administration, Intravenous , Aged , Cohort Studies , Female , Fibrinolytic Agents/therapeutic use , Humans , Logistic Models , Male , Middle Aged , Odds Ratio , Retrospective Studies , Thrombolytic Therapy/methods , Tissue Plasminogen Activator/adverse effects
20.
J Stroke Cerebrovasc Dis ; 27(10): 2755-2760, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30037649

ABSTRACT

GOAL: Epilepsy is a major complication of stroke. There have been suggestions that patients with cardioembolic stroke are at a greater risk of developing seizures than other stroke subtypes. However, the incidence of atrial fibrillation (AF) and cardioembolic stroke varies considerably across countries, generally higher in Western populations than in Asian populations. This study assessed whether ethnicity affects the association between AF and poststroke seizure (PSS) development. We hypothesized that Royal Melbourne Hospital ([RMH] Melbourne) patients will have significantly higher incidence of AF-related PSS than in the Jinling Hospital (Nanjing) population. MATERIALS AND METHODS: This was a retrospective, multicenter cohort study including patients with anterior circulation ischemic stroke admitted between 2008 and 2015. Occurrences of PSS were ascertained by reviewing medical records or telephone follow-up. To test the hypothesis of an interaction between ethnicity and AF for PSS occurrence, a logistic regression model with AF and ethnicity together with an ethnicity-by-AF interaction term was used. FINDINGS: Of 782 patients followed-up for seizure development at RMH, 247 (31.6%) patients had AF, of whom 10 (4%) developed PSS. Of 1185 patients followed-up and included at JH, 54 (4.8%) patients with AF, of whom 4 (7.4%) developed PSS. At RMH, no significant association was found between AF and PSS; odds ratio .75, 95% confidence interval .4-1.6, (P = .4). At JH, there was a significant association between AF and increased PSS: OR 4.0, 95% CI 1.3-12.1, (P = .01), P for interaction = .03. CONCLUSION: Further understanding of genetic risks and environmental differences across ethnic populations and the role in PSS is required.


Subject(s)
Asian People , Atrial Fibrillation/ethnology , Environment , Health Status Disparities , Native Hawaiian or Other Pacific Islander , Seizures/ethnology , Stroke/ethnology , Aged , Aged, 80 and over , Asian People/genetics , Atrial Fibrillation/diagnosis , Atrial Fibrillation/genetics , China/epidemiology , Female , Gene-Environment Interaction , Genetic Predisposition to Disease , Humans , Incidence , Logistic Models , Male , Middle Aged , Multivariate Analysis , Native Hawaiian or Other Pacific Islander/genetics , Odds Ratio , Retrospective Studies , Risk Assessment , Risk Factors , Seizures/diagnosis , Stroke/diagnosis , Victoria/epidemiology
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