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2.
JHEP Rep ; 6(6): 101037, 2024 Jun.
Article En | MEDLINE | ID: mdl-38721342

Background & Aims: Inflammatory bowel disease (IBD) is commonly associated with extraintestinal complications, including autoimmune liver disease. The co-occurrence of IBD and primary biliary cholangitis (PBC) has been increasingly observed, but the underlying relationship between these conditions remains unclear. Methods: Using summary statistics from genome-wide association studies (GWAS), we investigated the causal effects between PBC and IBD, including Crohn's disease (CD) and ulcerative colitis (UC). We also analyzed the shared genetic architecture between IBD and PBC using data from GWAS, bulk-tissue RNA sequencing, and single cell RNA sequencing, and explored potential functional genes. Result: There was a strong positive genetic correlation between PBC and IBD (linkage disequilibrium score regression: rg = 0.2249, p = 3.38 × 10-5). Cross-trait analysis yielded 10 shared-risk single nucleotide polymorphisms (SNPs), as well as nine novel SNPs, which were associated with both traits. Using Mendelian randomization, a stable causal effect was established of PBC on IBD. Genetically predicted PBC was found to have a risk effect on IBD (1.105; 95% CI: 1.058-1.15; p = 1.16 × 10-10), but not vice versa. Shared tissue-specific heritability enrichment was identified for PBC and IBD (including CD and UC) in lung, spleen, and whole-blood samples. Furthermore, shared enrichment was observed of specific cell types (T cells, B cells, and natural killer cells) and their subtypes. Nine functional genes were identified based on summary statistics-based Mendelian randomization. Conclusions: This study detected shared genetic architecture between IBD and PBC and demonstrated a stable causal relationship of genetically predicted PBC on the risk of IBD. These findings shed light on the biological basis of comorbidity between IBD and PBC, and have important implications for intervention and treatment targets of these two diseases simultaneously. Impact and Implications: The discovery of novel shared single nucleotide polymorphisms (SNPs) and functional genes provides insights into the common targets between inflammatory bowel disease (IBD) and primary biliary cholangitis (PBC), serving as a basis for new drug development and contributing to the study of disease pathogenesis. Additionally, the established significant causality and genetic correlation underscore the importance of clinical intervention in preventing the comorbidity of IBD and PBC. The enrichment of SNP heritability in specific tissues and cell types reveals the role of immune factors in the potential disease mechanisms shared between IBD and PBC. This stimulates further research on potential interventions and could lead to the development of new targets for immune-based therapies.

3.
J Neurol Surg B Skull Base ; 85(3): 234-240, 2024 Jun.
Article En | MEDLINE | ID: mdl-38721366

Background Studies on basilar artery occlusion are relatively few compared with those of anterior circulation stroke. The aim of the present study was to compare the efficacy of endovascular therapy (EVT) in patients with basilar artery occlusion classified as large artery atherosclerosis (LAA) and cardioembolism (CE), and to analyze the independent risk factors affecting the prognosis of EVT. Methods A total of 123 people were assigned to the LAA and CE groups (97 to the LAA and 26 to the CE). The primary outcome was a modified Rankin Scale (mRS) score of 2 or lower at 90 days. The primary safety outcome was mortality at 90 days. Secondary safety endpoints included the rates of symptomatic intracranial hemorrhage and reinfarction. Multiple logistic regression was used to screen out independent risk factors for EVT prognosis of the LAA and CE groups. Results In the analysis, the patients with LAA stroke had better collateral circulation (American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology [SIR] score of 2-4; 61.9 vs. 19.2%, p = 0.000), and higher angioplasty rate (32.0 vs. 3.8%, p = 0.002). The proportions of patients with a 90-day mRS score of 0 to 2 and 90-day mortality were not found to be statistically significant between the two groups. Multivariate logistic regression analysis indicated that age, SIR, white blood cell, blood glucose, and modified thrombolysis in cerebral infarction were independent risk factors for the poor prognosis of EVT in the LAA group. Conclusion Although there were differences in clinical characteristics and imaging features between LAA and CE, there was no evidence of a significant difference in prognosis after EVT. In addition, the National Institutes of Health Stroke Scale score was not among the independent risk factors affecting the prognosis of the LAA group.

4.
J Infect Dis ; 2024 May 09.
Article En | MEDLINE | ID: mdl-38723186

Targeted therapy is an attractive approach for treating infectious diseases. Affibody molecules have similar capability to antibodies that facilitate molecular recognition in both diagnostic and therapeutic applications. Targeting major outer membrane protein (MOMP) for treating infection of Chlamydia trachomatis, one of the most common sexually transmitted pathogens, is a promising therapeutic approach. Previously, we have reported a MOMP-specific affibody (ZMOMP:461) from phage display library. Here, we first fused it with modified Pseudomonas Exotoxin (PE38KDEL) and a cell-penetrating peptide (CPP) to develop an affitoxin, Z461X-CPP. We then verified the addition of both toxin and CPPs that did not affect the affinitive capability of ZMOMP:461 to MOMP. Upon uptake by C.trachomatis-infected cells, Z461X-CPP induced cell apoptosis in vitro. In animal model, Z461X significantly shortened the duration of C. trachomatis infection and prevented pathological damage in mouse reproductive system. These findings provide compelling evidence that the MOMP-specific affitoxin has great potential for targeting therapy of C. trachomatis infection.

5.
Food Chem ; 452: 139522, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38723568

ß-lactoglobulin (ß-Lg) is a major food allergen, there is an urgent need to develop a rapid method for detecting ß-Lg in order to avoid contact or ingestion by allergic patients. Peptide aptamers have high affinity, specificity, and stability, and have broad prospects in the field of rapid detection. Using ß-Lg as the target, this study screened 11 peptides (P1-11) from a phage display library. Using molecular docking technology to predict binding energy and binding mode of proteins and peptides. Select the peptides with the best binding ability to ß-Lg (P5, P7, P8) through ELISA. Combining them with whey protein, casein, and bovine serum protein, it was found that P7 has the best specificity for ß-Lg, with an inhibition rate of 87.99%. Verified by molecular dynamics that P7 binds well with ß-Lg. Therefore, this peptide can be used for the recognition of ß-Lg, becoming a new recognition element for detecting ß-Lg.

7.
J Colloid Interface Sci ; 669: 766-774, 2024 May 09.
Article En | MEDLINE | ID: mdl-38744154

Aqueous Zn-ion hybrid supercapacitors (ZHSs) are attracting significant attention as a promising electrochemical energy storage system. However, carbon cathodes of ZHSs exhibit unsatisfactory ion storage performance due to the large size of hydrated Zn-ions (e.g., [Zn(H2O)6]2+), which encumbers compact ion arrangement and rapid ion transport at the carbon-electrolyte interfaces. Herein, a porous carbon material (HMFC) with abundant sub-nanopores is synthesized to optimize the ion storage performance of the carbon cathode in ZHSs, in which the sub-nanopores effectively promote the dehydration of hydrated Zn-ions and thus optimize the ion storage performance of the carbon cathode in ZHSs. A novel strategy is proposed to study the dehydration behaviors of hydrated Zn-ions in carbon cathodes, including quantitatively determining the desolvation activation energy of hydrated Zn-ions and in-situ monitoring active water content at the carbon-electrolyte interface. The sub-nanopores-induced desolvation effect is verified, and its coupling with large specific surface area and hierarchically porous structure endows the HMFC cathode with improved electrochemical performance, including a 53 % capacity increase compared to the carbon cathode counterpart without sub-nanopores, fast charge/discharge ability that can output 46.0 Wh/kg energy within only 4.4 s, and 98.2 % capacity retention over 20,000 charge/discharge cycles. This work provides new insights into the rational design of porous carbon cathode materials toward high-performance ZHSs.

8.
Hum Cell ; 2024 May 14.
Article En | MEDLINE | ID: mdl-38744794

Epithelial mesenchymal transition (EMT) occurring in retinal pigment epithelial cells (RPE) is a crucial mechanism that contributes to the development of age-related macular degeneration (AMD), a pivotal factor leading to permanent vision impairment. Long non-coding RNAs (lncRNAs) have emerged as critical regulators orchestrating EMT in RPE cells. In this study, we explored the function of the lncRNA CYTOR (cytoskeleton regulator RNA) in EMT of RPE cells and its underlying mechanisms. Through weighted correlation network analysis, we identified CYTOR as an EMT-related lncRNA associated with AMD. Experimental validation revealed that CYTOR orchestrates TGF-ß1-induced EMT, as well as proliferation and migration of ARPE-19 cells. Further investigation demonstrated the involvement of CYTOR in regulating the WNT5A/NFAT1 pathway and NFAT1 intranuclear translocation in the ARPE-19 cell EMT model. Mechanistically, CHIP, EMSA and dual luciferase reporter assays confirmed NFAT1's direct binding to CYTOR's promoter, promoting transcription. Reciprocally, CYTOR overexpression promoted NFAT1 expression, while NFAT1 overexpression increased CYTOR transcription. These findings highlight a mutual promotion between CYTOR and NFAT1, forming a positive feedback loop that triggers the EMT phenotype in ARPE-19 cells. These discoveries provide valuable insights into the molecular mechanisms of EMT and its association with AMD, offering potential avenues for targeted therapies in EMT-related conditions, including AMD.

9.
Clin Lab ; 70(5)2024 May 01.
Article En | MEDLINE | ID: mdl-38747909

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been a significant global health issue in recent years. Numerous studies indicate that COVID-19 during pregnancy is associated with an increased likelihood of pregnancy complications. Additionally, pregnancy itself is known to elevate the risk of severe SARS-CoV-2 infection. To explore the potential impact of SARS-CoV-2 infection on the probability of Down syndrome in fetuses, we conducted serological testing of Down syndrome markers in pregnant women who had contracted the virus. METHODS: Serological experiments were conducted utilizing a particle chemiluminescence test. The cohort of pregnant women was categorized into three groups: a control group with no infection, a group infected with SARS-CoV-2 Omicron within the first six weeks of gestation, and a group infected beyond the sixth week of gestation. RESULTS: In the group of individuals infected within 6 gestational weeks, the infection resulted in a decrease in alpha-fetoprotein (AFP) levels and a higher positive rate of Down syndrome screening tests (p ˂ 0.05). However, in this study, SARS-CoV-2 infection did not lead to an increase in the occurrence of Down syndrome in the fetus. The positive rate of women infected beyond 6 gestational weeks was slightly higher than the non-infected group (6.2% vs. 5.7%), but these differences were not statistically significant (p > 0.05). Within the group infected beyond 6 gestational weeks, there was, compared to the control group, a decrease in free beta human chorionic gonadotropin (ß-hCG) levels (p < 0.05). CONCLUSIONS: This study presents a novel investigation into the impact of SARS-CoV-2 infection on AFP and ß-hCG levels. It has been observed that pregnant women who contract SARS-CoV-2 may exhibit an increased likelihood of positive results in serum tests conducted for Down syndrome screening. However, it is important to note that the occurrence of Down syndrome in the developing fetus does not appear to be elevated. To validate these findings, additional research involving larger and diverse cohorts is necessary.


COVID-19 , Down Syndrome , Pregnancy Complications, Infectious , SARS-CoV-2 , alpha-Fetoproteins , Humans , Down Syndrome/diagnosis , Down Syndrome/blood , alpha-Fetoproteins/analysis , Female , Pregnancy , COVID-19/diagnosis , COVID-19/blood , COVID-19/epidemiology , Pregnancy Complications, Infectious/blood , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/virology , Adult , Prenatal Diagnosis/methods , Biomarkers/blood
10.
Anal Chem ; 2024 May 15.
Article En | MEDLINE | ID: mdl-38748451

Unraveling bacterial identity through Raman scattering techniques has been persistently challenging due to homogeneously amplified Raman signals across a wide variety of bacterial molecules, predominantly protein- or nucleic acid-mediated. In this study, we present an approach involving the use of silver nanoparticles to completely and uniformly "mask" adsorption on the surface of bacterial molecules through sodium borohydride and sodium chloride. This approach enables the acquisition of enhanced surface-enhanced Raman scattering (SERS) signals from all components on the bacterial surface, facilitating rapid, specific, and label-free bacterial identification. For the first time, we have characterized the identity of a bacterium, including its DNA, metabolites, and cell walls, enabling the accurate differentiation of various bacterial strains, even within the same species. In addition, we embarked on an exploration of the origin and variability patterns of the main characteristic peaks of Gram-positive and Gram-negative bacteria. Significantly, the SERS peak ratio was found to determine the inflection point of accelerated bacterial death upon treatment with antimicrobials. We further applied this platform to identify 15 unique clinical antibiotic-resistant bacterial strains, including five Escherichia coli strains in human urine, a first for Raman technology. This work has profound implications for prompt and accurate identification of bacteria, particularly antibiotic-resistant strains, thereby significantly enhancing clinical diagnostics and antimicrobial treatment strategies.

11.
Materials (Basel) ; 17(9)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38730777

Titanium zirconium vanadium (TiZrV) is a widely used non-evaporable getter (NEG) material with the characteristics of a low activation temperature and a large gas absorption capacity. At present, the research on TiZrV getters mainly focuses on the thin-film state, with little research on the bulk state. In this paper, a TiZrV getter was optimized by adding Al, and the phase structure, activation properties, and gettering performance were studied. With the addition of Al, the α-Zr phase and Ti2Zr phase changed into the Ti-Zr phase and Al-Zr, Al-Ti phase. The newly generated phase promoted the diffusion of hydrogen and oxygen atoms. The activation temperature decreased significantly, as shown in the in situ XPS results. The H2 and CO gettering performance of TiZrVAl samples was promoted to 2073 cm3·s-1 and 1912.8 cm3·s-1, increased by 40.7% and 40.3%. This paper provides valuable ideas for optimizing the properties of bulk TiZrV getters.

12.
Plants (Basel) ; 13(9)2024 Apr 30.
Article En | MEDLINE | ID: mdl-38732475

JASMONATE-ZIM DOMAIN (JAZ) repressor proteins work as co-receptors in the jasmonic acid (JA) signalling pathway and are essential for plant development and environmental adaptation. Despite wheat being one of the main staple food crops, until recently, comprehensive analysis of its JAZ gene family has been limited due to the lack of complete and high-quality reference genomes. Here, using the latest reference genome, we identified 17 JAZ genes in the wheat D-genome donor Aegilops tauschii. Then, 54 TaJAZs were identified in common wheat. A systematic examination of the gene structures, conserved protein domains, and phylogenetic relationships of this gene family was performed. Five new JAZ genes were identified as being derived from tandem duplication after wheat divergence from other species. We integrated RNA-seq data and yield QTL information and found that tandemly duplicated TaJAZ genes were prone to association with spike-related traits. Moreover, 12 TaJAZ genes were located within breeding selection sweeps, including 9 tandemly duplicated ones. Haplotype variation analysis of selected JAZ genes showed significant association of TaJAZ7A and TaJAZ13A with thousand-grain weight. Our work provides a clearer picture of wheat JAZ gene evolution and puts forward the possibility of using these genes for wheat yield improvement.

13.
ACS Omega ; 9(18): 20293-20303, 2024 May 07.
Article En | MEDLINE | ID: mdl-38737065

Phosphorus and nitrogen are important elements in both environmental cycles and biological growth, and their imbalance can lead to serious environmental and biological problems. It is important to be able to monitor the concentration of nitrate and phosphate in the water online. In this paper, a bifunctional boron-doped diamond (BDD) electrode with repeatable electrochemical renewal and modification ability has been developed and used as a shared working electrode for the determination of nitrate and phosphate. First, phosphate can be detected directly with a bare BDD electrode. After a thin copper (Cu) layer was electrodeposited on the BDD electrode, nitrate could be determined. The copper layer is then removed under a positive voltage, and the BDD electrode is renewed and can be used again for phosphate detection. This method enables the detection of both phosphate and nitrate while also improving the stability and repeatability through the renewal of the electrode surface. The segmented linear ranges for phosphate were 0.02-0.4 and 0.4-3 mg/L with a detection limit of 0.004 mg/L. The sensor detected nitrate in a wide concentration range, with segmented linear relationships in the ranges of 0.07-3 and 3-100 mg/L, with a detection limit of 0.065 mg/L. The electrochemical sensor based on the BDD electrode has a good reproducibility for phosphate and nitrate detection. The relative standard deviation (RSD) values of the current responses were 2.98, 2.79, 1.66, 1.81, and 1.23%, respectively, for 35 consecutive tests in 0.05, 0.2, 0.5, 1, and 1.5 mg/L phosphate solution. The RSD values of the current responses were 2.00, 0.97, and 1.03%, respectively, for 25 consecutive tests in 5, 7, and 10 mg/L nitrate solution.

14.
Transl Cancer Res ; 13(4): 1876-1886, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38737678

Background: Among human papillomavirus (HPV) type, HPV16 displays the strongest carcinogenic capacity for cervical cancer, but the mechanism underlying this phenomenon remains unclear. We investigated the effect and the underlying mechanism of HPV16 on higher carcinogenic capacity than HPV58. Methods: We collected 4,030 cervical exfoliated cell samples for genotyping HPV using HybriBio's proprietary flow-through hybridization technique, liquid-based cytology (LBC), colposcopy, and biopsies if indicated. Four plasmids containing E6 and E7 of HPV16 and 58 were constructed and transfected into 293T and U2OS cells. We detected the cell phenotype using Cell Counting Kit 8 (CCK8) assay, Transwell assay, flow cytometry, and apoptosis assay; the expression of retinoblastoma protein (Rb) and phosphorylated Rb (pRb) was determined via Western blot; and the cell activity was determined via a zebrafish model treated with or without roscovitine. Results: The positive rates of HPV16 and 58 were, respectively, 18.9% and 19.7% in the ≤ low-grade squamous intraepithelial lesion (LSIL) group, 49.5% and 19.6% (P<0.001) in the high-grade squamous intraepithelial lesion (HSIL) group, 65.3% and 9.0% (P<0.001) in the cancer group. In vitro, both 293T and U2OS cells with overexpressed HPV16 E6 and E7 displayed significantly higher cell proliferation, faster cell invasion, decreased cell apoptosis, and accelerated cell cycle from G1 phase to S phase compared to those with overexpressed HPV58 E6 and E7 (all P values <0.05). Rb loss of function was observed in cells with HPV16 E7 overexpression, while a greater level of phosphorylated Rb was observed in cells with HPV58 E7 overexpression. Roscovitine restored Rb expression and decreased the cell activity in zebrafish. Conclusions: HPV16 possesses a stronger carcinogenic ability than does HPV 58, and the mechanism underlying this effect may be the impairment of the E7-Rb pathway.

15.
Nat Commun ; 15(1): 3896, 2024 May 08.
Article En | MEDLINE | ID: mdl-38719899

As one of the most attractive methods for the synthesis of ordered hierarchically porous crystalline materials, the soft-template method has not appeared in covalent organic frameworks (COFs) due to the incompatibility of surfactant self-assembly and guided crystallization process of COF precursors in the organic phase. Herein, we connect the soft templates to the COF backbone through ionic bonds, avoiding their crystallization incompatibilities, thus introducing an additional ordered arrangement of soft templates into the anionic microporous COFs. The ion exchange method is used to remove the templates while maintaining the high crystallinity of COFs, resulting in the construction of COFs with ordered hierarchically micropores/mesopores, herein named OHMMCOFs (OHMMCOF-1 and OHMMCOF-2). OHMMCOFs exhibit significantly enhanced functional group accessibility and faster mass transfer rate. The extrinsic porosity can be adjusted by changing the template length, concentration, and ratio. Cationic guanidine-based COFs (OHMMCOF-3) are also constructed using the same method, which verifies the scalability of the soft-template strategy. This work provides a path for constructing ordered and tunable extrinsic porosity in COFs with greatly improved mass transfer efficiency and functional group accessibility.

16.
Eur J Med Res ; 29(1): 277, 2024 May 09.
Article En | MEDLINE | ID: mdl-38725045

BACKGROUND: Metabolic disorders (MetDs) have been demonstrated to be closely linked to numerous diseases. However, the precise association between MetDs and pulmonary tuberculosis (PTB) remains poorly understood. METHOD: Summary statistics for exposure and outcomes from genome-wide association studies (GWASs) for exposures and outcomes were obtained from the BioBank Japan Project (BBJ) Gene-exposure dataset. The 14 clinical factors were categorized into three groups: metabolic laboratory markers, blood pressure, and the MetS diagnostic factors. The causal relationship between metabolic factors and PTB were analyzed using two-sample Mendelian Randomization (MR). Additionally, the direct effects on the risk of PTB were investigated through multivariable MR. The primary method employed was the inverse variance-weighted (IVW) model. The sensitivity of this MR analysis was evaluated using MR-Egger regression and the MR-PRESSO global test. RESULTS: According to the two-sample MR, HDL-C, HbA1c, TP, and DM were positively correlated with the incidence of active TB. According to the multivariable MR, HDL-C (IVW: OR 2.798, 95% CI 1.484-5.274, P = 0.001), LDL (IVW: OR 4.027, 95% CI 1.140-14.219, P = 0.03) and TG (IVW: OR 2.548, 95% CI 1.269-5.115, P = 0.009) were positively correlated with the occurrence of PTB. TC (OR 0.131, 95% CI 0.028-0.607, P = 0.009) was negatively correlated with the occurrence of PTB. We selected BMI, DM, HDL-C, SBP, and TG as the diagnostic factors for metabolic syndrome. DM (IVW, OR 1.219, 95% CI 1.040-1.429 P = 0.014) and HDL-C (IVW, OR 1.380, 95% CI 1.035-1.841, P = 0.028) were directly correlated with the occurrence of PTB. CONCLUSIONS: This MR study demonstrated that metabolic disorders, mainly hyperglycemia, and dyslipidemia, are associated with the incidence of active pulmonary tuberculosis.


Genome-Wide Association Study , Mendelian Randomization Analysis , Metabolic Diseases , Tuberculosis, Pulmonary , Humans , Tuberculosis, Pulmonary/genetics , Tuberculosis, Pulmonary/epidemiology , Tuberculosis, Pulmonary/blood , Metabolic Diseases/genetics , Metabolic Diseases/epidemiology , Risk Factors
17.
Front Psychiatry ; 15: 1248424, 2024.
Article En | MEDLINE | ID: mdl-38726382

Background: Coronary heart disease has a high incidence rate, a high mortality rate, a high recurrence rate, and a high medical cost. In addition, some patients need to undergo percutaneous coronary artery stent implantation (CASI), which is a kind of traumatic treatment. Patients can easily experience negative emotions such as anxiety and depression after surgery, which seriously affects quality of life. Objectives: The aim of this study was to evaluate the effectiveness of an empowerment-based telephone follow-up intervention on resilience and quality of life in patients who underwent CASI. Design: The design of the study is a randomized controlled trial. Methods: A total of 92 patients were recruited after CASI from the Internal Medicine Cardiovascular Department of a Grade A tertiary hospital in Xi'an, China. The patients were randomly divided into a control group and an intervention group. The control group performed routine care, whereas the intervention group developed a telephone follow-up program based on empowerment theory while carrying out routine care. Patients were investigated using the coronary heart disease-related knowledge questionnaire, the Connor-Davidson Resilience Scale (CD-RISC), and the 36-Item Short-Form Health Survey (SF-36) to compare the effects of the intervention before and after 1 month of intervention. Results: After a 1-month telephone follow-up intervention based on the empowerment theory for patients after CASI, the variations in knowledge related to coronary heart disease and all of its subscale scores were greater in the intervention group than in the control group. Except for the three dimensions of risk factor, induction factor, and rehabilitation-related knowledge, the variations in knowledge related to coronary heart disease and the other subscale scores were significantly different between the two groups (p < 0.05). The variations in resilience and scores on the three subscales in the intervention group were greater than those in the control group, and the difference between the two groups was statistically significant (p < 0.05). The variations in the quality of life and overall health, emotional functions, and social functions were significantly greater in the intervention group than in the control group (p < 0.05). Conclusions: A telephone follow-up intervention based on the empowerment theory can effectively improve the resilience and quality of life of patients after CASI. This follow-up approach can provide a theoretical basis and practical reference for hospitals and communities to carry out targeted continuing nursing for patients after CASI. The long-term effects of the intervention and its underlying mechanisms require further study. Clinical trial registration: http://www.chictr.org.cn/showproj.aspx?proj=173682, identifier ChiCTR2200064950.

18.
Angew Chem Int Ed Engl ; : e202405408, 2024 May 10.
Article En | MEDLINE | ID: mdl-38728168

Ring-opening polymerization (ROP) offers a striking solution to solve problems encountered in step-growth condensation polymerization, including precise control over molecular weight, molecular weight distribution, and topology. This has inspired our interest in ROP of cycloalkanes with an ultimate goal to rethink polyolefins, which clearly poses a number of challenges. Practicality of ROP of cycloalkanes is actually limited by their low polymerizability and elusive mechanisms which arise from significantly varied ring size and non-polar C-C bonds in monomers. In this work, by using Lewis acid/Brønsted base/C(sp3)-H initiator system previously developed in our laboratory, we focus on cyclobutanes and explore the positional and electronic effects of substituents on the ring, namely electron push-pull effect, in promoting controlled polymerization to afford densely functionalized poly(cyclobutanes), as well as catalytic degradation of obtained polymers for upcycling. More importantly, experiments and DFT calculations unveil considerable population of Lewis-acid-induced thermostabilized 1,4-zwitterions, which distinguish cyclobutanes from cyclopropanes and others. All these findings would shed light on catalytic synthesis and degradation of saturated all-carbon main-chain polymers, as well as small molecule transformations of cyclobutanes.

19.
Ecotoxicol Environ Saf ; 278: 116432, 2024 May 09.
Article En | MEDLINE | ID: mdl-38728947

Cadmium (Cd) pollution is a serious global environmental problem, which requires a global concern and practical solutions. Microbial remediation has received widespread attention owing to advantages, such as environmental friendliness and soil amelioration. However, Cd toxicity also severely deteriorates the remediation performance of functional microorganisms. Analyzing the mechanism of bacterial resistance to Cd stress will be beneficial for the application of Cd remediation. In this study, the bacteria strain, up to 1400 mg/L Cd resistance, was employed and identified as Proteus mirabilis Ch8 (Ch8) through whole genome sequence analyses. The results indicated that the multiple pathways of immobilizing and detoxifying Cd maintained the growth of Ch8 under Cd stress, which also possessed high Cd extracellular adsorption. Firstly, the changes in surface morphology and functional groups of Ch8 cells were observed under different Cd conditions through SEM-EDS and FTIR analyses. Under 100 mg/L Cd, Ch8 cells exhibited aggregation and less flagella; the Cd biosorption of Ch8 was predominately by secreting exopolysaccharides (EPS) and no significant change of functional groups. Under 500 mg/L Cd, Ch8 were present irregular polymers on the cell surface, some cells with wrapping around; the Cd biosorption capacity exhibited outstanding effects (38.80 mg/g), which was mainly immobilizing Cd by secreting and interacting with EPS. Then, Ch8 also significantly enhanced the antioxidant enzyme activity and the antioxidant substance content under different Cd conditions. The activities of SOD and CAT, GSH content of Ch8 under 500 mg/L Cd were significantly increased by 245.47%, 179.52%, and 241.81%, compared to normal condition. Additionally, Ch8 significantly induced the expression of Acr A and Tol C (the resistance-nodulation-division (RND) efflux pump), and some antioxidant genes (SodB, SodC, and Tpx) to reduce Cd damage. In particular, the markedly higher expression levels of SodB under Cd stress. The mechanism of Ch8 lays a foundation for its application in solving soil remediation.

20.
Fitoterapia ; : 106000, 2024 May 08.
Article En | MEDLINE | ID: mdl-38729248

Five new characteristic cembrane-type diterpenoids (olibacartiols A-E, 1-5) were acquired from the gum resin of Boswellia carterii. The structures of these diterpenoids were characterized by detailed spectroscopic analysis, and compounds 1-3 were unambiguously confirmed by single-crystal X-ray diffraction experiments. The anti-inflammatory activities of the isolated compounds were evaluated using LPS-induced BV2 cell model and compounds 2-5 showed moderate NO inhibitory effects with IC50 values of 8.84 ±â€¯1.02, 9.82 ±â€¯1.95, 9.75 ±â€¯2.24, and 7.39 ±â€¯1.24 µM, respectively.

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