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1.
Front Bioeng Biotechnol ; 12: 1406722, 2024.
Article in English | MEDLINE | ID: mdl-39011153

ABSTRACT

Unveiling the potential application of psychrophilic polymerases as candidates for polymerase-nanopore long-read sequencing presents a departure from conventional choices such as thermophilic Bacillus stearothermophilus (Bst) renowned for its limitation in temperature and mesophilic Bacillus subtilis phage (phi29) polymerases for limitations in strong exonuclease activity and weak salt tolerance. Exploiting the PB-Bst fusion DNA polymerases from Psychrobacillus (PB) and Bacillus stearothermophilus (Bst), our structural and biochemical analysis reveal a remarkable enhancement in salt tolerance and a concurrent reduction in exonuclease activity, achieved through targeted substitution of a pivotal functional domain. The sulfolobus 7-kDa protein (Sso7d) emerges as a standout fusion domain, imparting significant improvements in PB-Bst processivity. Notably, this study elucidates additional functional sites regulating exonuclease activity (Asp43 and Glu45) and processivity using artificial nucleotides (Glu266, Gln283, Leu334, Glu335, Ser426, and Asp430). By disclosing the intricate dynamics in exonuclease activity, strand displacement, and artificial nucleotide-based processivity at specific functional sites, our findings not only advance the fundamental understanding of psychrophilic polymerases but also provide novel insights into polymerase engineering.

2.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-39065738

ABSTRACT

The efforts to discover HIV therapeutics have continued since the first human immunodeficiency virus (HIV) infected patient was confirmed in the 1980s. Ten years later, the first HIV drug, zidovudine (AZT), targeting HIV reverse transcriptase, was developed. Meanwhile, scientists were enlightened to discover new drugs that target different HIV genes, like integrase, protease, and host receptors. Combination antiretroviral therapy (cART) is the most feasible medical intervention to suppress the virus in people with HIV (PWH) and control the epidemic. ART treatment has made HIV a chronic infection rather than a fatal disease, but ART does not eliminate latent reservoirs of HIV-1 from the host cells; strict and life-long adherence to ART is required for the therapy to be effective in patients. In this review, we first discussed the scientific history of conventional HIV drug discovery since scientists need to develop more and more drugs to solve drug-resistant issues and release the side effects. Then, we summarized the novel research technologies, like gene editing, applied to HIV treatment and their contributions to eliminating HIV as a complementary therapy.

3.
Arch Oral Biol ; 164: 106003, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38781741

ABSTRACT

OBJECTIVE: This study aimed to investigate the expression of serine protease inhibitor kazal type 1 (SPINK1) and its carcinogenic effect in oral tongue squamous cell carcinoma (OTSCC). DESIGN: Initially, bioinformatics analysis was conducted using data from The Cancer Genome Atlas and Gene Expression Omnibus to compare SPINK1 mRNA expression between malignant and adjacent tissues. Subsequently, the impact of differential expression on survival and other clinical variables was examined. Additionally, histology microarray analysis was performed to assess SPINK1 protein expression in 35 cases of malignant and adjacent tissues. Finally, alterations in SPINK1 expression were evaluated to determine its biological phenotypes in OTSCC, including proliferation, apoptosis, invasion, and metastasis. RESULTS: OTSCC tissues exhibit higher levels of SPINK1 compared to surrounding cancerous tissues. Notably, increased SPINK1 expression correlates with the pathological N stage and independently predicts overall survival among patients with OTSCC. CONCLUSION: Suppression of SPINK1 inhibited OTSCC cell proliferation, invasion, and motility while promoting apoptosis. These findings suggest that SPINK1 may serve as a prognostic biomarker as well as a potential therapeutic target for managing OTSCC.


Subject(s)
Apoptosis , Biomarkers, Tumor , Carcinoma, Squamous Cell , Cell Proliferation , Disease Progression , Neoplasm Invasiveness , Tongue Neoplasms , Trypsin Inhibitor, Kazal Pancreatic , Humans , Tongue Neoplasms/pathology , Tongue Neoplasms/genetics , Tongue Neoplasms/metabolism , Trypsin Inhibitor, Kazal Pancreatic/genetics , Prognosis , Male , Female , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/metabolism , Middle Aged , Apoptosis/genetics , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/genetics , Cell Movement/genetics , RNA, Messenger/metabolism , RNA, Messenger/genetics , Cell Line, Tumor , Computational Biology
4.
Front Oncol ; 14: 1387735, 2024.
Article in English | MEDLINE | ID: mdl-38720807

ABSTRACT

Background: Rhabdomyosarcoma(RMS) is the most common soft tissue sarcoma in children and single nucleotide polymorphisms(SNPs) in certain genes influence risk of RMS. Although FOXO3 had been reported in multiple cancers including RMS, the role of FOXO3 polymorphisms in RMS remains unclear. In this case-control study, we evaluated the association of FOXO3 SNPs with RMS risk and prognosis in children. Methods: Four FOXO3 SNPs(rs17069665 A>G, rs4946936 T>C, rs4945816 C>T and rs9400241 C>A) were genotyped in 110 RMS cases and 359 controls. The associations between FOXO3 polymorphisms and RMS risk were determined by odds ratios(ORs) with 95% confidence intervals(CIs). The associations of rs17069665 and rs4946936 with overall survival in RMS children were estimated using the Kaplan-Meier method and log-rank test. Functional analysis in silico was performed to estimate the probability that rs17069665 and rs4946936 might influence the regulation of FOXO3. Results: We found that rs17069665 (GG vs. AA+AG, adjusted OR=2.96; 95%CI [1.10-3.32]; P=0.010) and rs4946936 (TC+CC vs. TT, adjusted OR=0.48; 95%CI [0.25-0.90]; P=0.023) were related to the increased and decreased RMS risk, respectively. Besides, rs17069665(P<0.001) and rs4946936(P<0.001) were associated with decreased and increased overall survival in RMS patients, respectively. Functional analysis showed that rs17069665 and rs4946936 might influence the transcription and expression of FOXO3 via altering the bindings to MYC, CTCF, and/or RELA. Conclusions: This study revealed that FOXO3 polymorphisms influence the RMS susceptibility and prognosis in children, and might altered the expression of FOXO3. FOXO3 polymorphism was suggested as a biomarker for RMS susceptibility and prognosis.

5.
J Clin Invest ; 134(5)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38426503

ABSTRACT

Tissue-intrinsic mechanisms that regulate severity of systemic pathogenic immune-mediated diseases, such as acute graft-versus-host disease (GVHD), remain poorly understood. Following allogeneic hematopoietic stem cell transplantation, autophagy, a cellular stress protective response, is induced in host nonhematopoietic cells. To systematically address the role of autophagy in various host nonhematopoietic tissues, both specific classical target organs of acute GVHD (intestines, liver, and skin) and organs conventionally not known to be targets of GVHD (kidneys and heart), we generated mice with organ-specific knockout of autophagy related 5 (ATG5) to specifically and exclusively inhibit autophagy in the specific organs. When compared with wild-type recipients, animals that lacked ATG5 in the gastrointestinal tract or liver showed significantly greater tissue injury and mortality, while autophagy deficiency in the skin, kidneys, or heart did not affect mortality. Treatment with the systemic autophagy inducer sirolimus only partially mitigated GVHD mortality in intestine-specific autophagy-deficient hosts. Deficiency of autophagy increased MHC class I on the target intestinal epithelial cells, resulting in greater susceptibility to damage by alloreactive T cells. Thus, autophagy is a critical cell-intrinsic protective response that promotes tissue tolerance and regulates GVHD severity.


Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Animals , Mice , Graft vs Host Disease/genetics , Graft vs Host Disease/pathology , Intestines/pathology , T-Lymphocytes/pathology , Epithelial Cells/pathology
6.
J Agric Food Chem ; 72(12): 6519-6525, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38497614

ABSTRACT

Histamine, found abundantly in salt-fermented foods, poses a risk of food poisoning. Natronobeatus ordinarius, a halophilic archaeon isolated from a salt lake, displayed a strong histamine degradation ability. Its histamine oxidase (HOD) gene was identified (hodNbs). This is the first report of an archaeal HOD. The HODNbs protein was determined to be a tetramer with a molecular weight of 307 kDa. HODNbs displayed optimum activity at 60-65 °C, 1.5-2.0 M NaCl, and pH 6.5. Notably, within the broad NaCl range between 0.5 and 2.5 M, HODNbs retained above 50% of its maximum activity. HODNbs exhibited good thermal stability, pH stability, and salinity tolerance. HODNbs was able to degrade various biogenic amines. The Vmax of HODNbs for histamine was 0.29 µmol/min/mg, and the Km was 0.56 mM. HODNbs exhibited high efficiency in histamine removal from fish sauce, namely, 100 µg of HODNbs degraded 5.63 mg of histamine (37.9%) in 10 g of fish sauce within 24 h at 50 °C. This study showed that HODNbs with excellent enzymatic properties has promising application potentials to degrade histamine in high-salt foods.


Subject(s)
Histamine , Oxidoreductases , Animals , Histamine/metabolism , Archaea/metabolism , Sodium Chloride , Biogenic Amines/metabolism , Food Safety
7.
Adv Mater ; 36(25): e2314097, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38466829

ABSTRACT

Planarly aligning 2D platelets is challenging due to their additional orientational freedom compared to 1D materials. This study reports a sequential dual-alignment approach, employing an extrusion-printing-induced shear force and rotating-magnetic-field-induced force couple for platelet planarly alignment in a yield-stress support bath. It is hypothesized that the partial alignment induced by a directional shear force facilitates subsequent axial rotation of the platelets for planar alignment under an external force couple, resulting in a synergistic alignment effect. This sequential dual-alignment approach achieves better planar alignment of 2D modified hexagonal boron nitride (mhBN). Specifically, the thermal conductivity of the 40 wt% mhBN/epoxy composite is significantly higher (692%) than that of unaligned composites, surpassing the cumulative effect of individual methods (only 133%) with a 5 times more synergistic effect. For 30, 40, and 50 wt% mhBN composites, the thermal conductivity values (5.9, 9.5, and 13.8 W m-1 K-1) show considerable improvement compared to the previously reported highest values (5.3, 6.6, and 8.6 W m-1 K-1). Additionally, a 3D mhBN/epoxy heat sink is printed and evaluated to demonstrate the feasibility of device fabrication. The approach enables the planar alignment of electrically or thermally conducting 2D fillers during 3D fabrication.

8.
Arch Microbiol ; 206(3): 102, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38353788

ABSTRACT

A plant growth hormone indoleacetic acid-producing strain LX3-4T was isolated from a carrot rhizosphere soil sample collected in Shandong Province, China. It is Gram-stain-positive, non-motile, and has irregular short rod-shaped cells. LX3-4T shared high 16S rRNA gene sequence identity with Microbacterium oleivorans DSM 16091T (99.4%), M. testaceum NBRC 12675T (98.6%), M. marinum DSM 24947T (98.5%), M. resistens NBRC 103078T (98.4%), and M. paraoxydans NBRC 103076T (98.3%). Phylogenetic analysis based on the concatenated gene sequences of 16S rRNA gene, housekeeping genes gryB and rpoB also showed the distinction between strain LX3-4T and other Microbacterium species. Furthermore, analysis of the average nucleotide identities (ANI), the average amino acid identity (AAI), and the digital DNA-DNA hybridization (dDDH) values between strain LX3-4T and its relatives revealed that strain LX3-4T represents a distinct species. The genomic DNA G + C content of the strain is 69.5%. It can grow at 25-37 °C (optimum 37 °C), pH 5.0-10.0 (optimum pH 6.0-8.0), and the range of NaCl concentration is 0-7% (w/v) (optimum 1-5%). The colonies on agar plates are smooth, translucent, and pale yellow. The main cellular fatty acids of strain LX3-4T are anteiso-C15:0, anteiso-C17:0, and iso-C16:0. The predominant respiratory quinones are MK-12 and MK-11. Diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid, and an unidentified phosphoglycolipid are major polar lipids. The cell-wall sugar of strain LX3-4T is glucose. The cell-wall peptidoglycan contains glycine, alanine, lysine, and glutamic acid. In addition, this strain carries nitrogen fixation genes and can grow in nitrogen-free medium. Based on the polyphasic data, strain LX3-4T represents a novel species of the genus Microbacterium, for which the name Microbacterium dauci sp. nov. is proposed with strain LX3-4T (= CCTCC AB 2023103T = LMG 33159T) designated as the type strain.


Subject(s)
Daucus carota , Growth Hormone , Plant Growth Regulators , Microbacterium , Phylogeny , RNA, Ribosomal, 16S/genetics , Rhizosphere , Indoleacetic Acids , DNA
9.
Int J Mol Sci ; 25(4)2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38396872

ABSTRACT

Carbon-semiconductor hybrid quantum dots are classical carbon dots with core carbon nanoparticles doped with a selected nanoscale semiconductor. Specifically, on those with the nanoscale TiO2 doping, denoted as CTiO2-Dots, their synthesis and thorough characterization were reported previously. In this work, the CTiO2-Dots were evaluated for their visible light-activated antibacterial function, with the results showing the effective killing of not only Gram-positive but also the generally more resistant Gram-negative bacteria. The hybrid dots are clearly more potent antibacterial agents than their neat carbon dot counterparts. Mechanistically, the higher antibacterial performance of the CTiO2-Dots is attributed to their superior photoexcited state properties, which are reflected by the observed much brighter fluorescence emissions. Also considered and discussed is the possibility of additional contributions to the antibacterial activities due to the photosensitization of the nanoscale TiO2 by its doped core carbon nanoparticles.


Subject(s)
Quantum Dots , Carbon/pharmacology , Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria , Gram-Positive Bacteria
10.
Cell Mol Biol Lett ; 29(1): 20, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38267862

ABSTRACT

BACKGROUND: Cisplatin (DDP) is a widely used chemotherapy drug for advanced cervical cancer (CC), but resistance poses a significant challenge. While miR-4739 has been implicated in tumor development, its specific role in regulating DDP resistance in CC remains unclear. METHODS: We analyzed the expression levels of miR-4739 and RHBDD2 in DDP-resistant and DDP-sensitive CC tissues using quantitative real-time polymerase chain reaction (PCR) and assessed their correlation through Spearman's correlation analysis. DDP-resistant CC cell lines (HeLa/DDP and SiHa/DDP) were established by gradually increasing DDP concentrations, followed by transfection with miR-4739 mimics, si-RHBDD2, or a RHBDD2 overexpression vector. A series of functional assays, including CCK-8 assay, colony formation, flow cytometry, and transwell assay were performed. The interaction between miR-4739 and RHBDD2 was confirmed by luciferase reporter assay. We examined the protein levels of RHBDD2, P-gP, MRP1, cleaved caspase-3, and E-cadherin through western blot analysis. Moreover, we generated xenograft tumors by injecting stably transfected HeLa/DDP cells into mice to compare their tumorigenesis capacity. RESULTS: We observed downregulation of miR-4739 and upregulation of RHBDD2 in DDP-resistant CC tissues and cell lines. MiR-4739 was shown to directly bind to RHBDD2 gene sequences to repress RHBDD2 expression in HeLa/DDP and SiHa/DDP cells. Our in vitro and in vivo experiments demonstrated that overexpressing miR-4739 overcame DDP resistance in CC cells by targeting RHBDD2. Furthermore, RHBDD2 overexpression reversed the effects of miR-4739 mimics on drug-resistance-related proteins (P-gP and MRP1) and the expression of cleaved caspase-3 and E-cadherin in HeLa/DDP cells. CONCLUSIONS: In summary, our study revealed that miR-4739 can reverse DDP resistance by modulating RHBDD2 in CC cells.


Subject(s)
MicroRNAs , Uterine Cervical Neoplasms , Humans , Animals , Mice , Female , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/genetics , Caspase 3 , Cisplatin/pharmacology , Cisplatin/therapeutic use , HeLa Cells , Cadherins , MicroRNAs/genetics , Membrane Proteins/genetics
11.
Science ; 383(6683): 622-629, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38271490

ABSTRACT

Paclitaxel is a well known anticancer compound. Its biosynthesis involves the formation of a highly functionalized diterpenoid core skeleton (baccatin III) and the subsequent assembly of a phenylisoserinoyl side chain. Despite intensive investigation for half a century, the complete biosynthetic pathway of baccatin III remains unknown. In this work, we identified a bifunctional cytochrome P450 enzyme [taxane oxetanase 1 (TOT1)] in Taxus mairei that catalyzes an oxidative rearrangement in paclitaxel oxetane formation, which represents a previously unknown enzyme mechanism for oxetane ring formation. We created a screening strategy based on the taxusin biosynthesis pathway and uncovered the enzyme responsible for the taxane oxidation of the C9 position (T9αH1). Finally, we artificially reconstituted a biosynthetic pathway for the production of baccatin III in tobacco.


Subject(s)
Alkaloids , Cytochrome P-450 Enzyme System , Metabolic Engineering , Paclitaxel , Plant Proteins , Taxoids , Taxus , Alkaloids/biosynthesis , Alkaloids/genetics , Bridged-Ring Compounds/chemistry , Bridged-Ring Compounds/metabolism , Ethers, Cyclic/chemistry , Ethers, Cyclic/metabolism , Paclitaxel/biosynthesis , Taxoids/metabolism , Taxus/enzymology , Taxus/genetics , Cytochrome P-450 Enzyme System/chemistry , Cytochrome P-450 Enzyme System/genetics , Plant Proteins/chemistry , Plant Proteins/genetics
12.
Nat Commun ; 15(1): 285, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38177144

ABSTRACT

Lassa virus (LASV) infection is expanding outside its traditionally endemic areas in West Africa, posing a pandemic biothreat. LASV-neutralizing antibodies, moreover, have proven difficult to elicit. To gain insight into LASV neutralization, here we develop a prefusion-stabilized LASV glycoprotein trimer (GPC), pan it against phage libraries comprising single-domain antibodies (nanobodies) from shark and camel, and identify one, D5, which neutralizes LASV. Cryo-EM analyses reveal D5 to recognize a cleavage-dependent site-of-vulnerability at the trimer apex. The recognized site appears specific to GPC intermediates, with protomers lacking full cleavage between GP1 and GP2 subunits. Guinea pig immunizations with the prefusion-stabilized cleavage-intermediate LASV GPC, first as trimer and then as a nanoparticle, induce neutralizing responses, targeting multiple epitopes including that of D5; we identify a neutralizing antibody (GP23) from the immunized guinea pigs. Collectively, our findings define a prefusion-stabilized GPC trimer, reveal an apex-situated site-of-vulnerability, and demonstrate elicitation of LASV-neutralizing responses by a cleavage-intermediate LASV trimer.


Subject(s)
Lassa Fever , Single-Domain Antibodies , Animals , Guinea Pigs , Lassa virus , Antibodies, Viral , Antibodies, Neutralizing
13.
J Coll Physicians Surg Pak ; 33(12): 1344-1348, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38062586

ABSTRACT

OBJECTIVE: To investigate the potential treatments for aortic stenosis and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using bioinformatics and systems biology. STUDY DESIGN: Observational study. Place and Duration of the Study: Jiading District Central Hospital affiliated Shanghai University of Medicine & Health Sciences, Shanghai, China, from August to December 2022. METHODOLOGY: GSE147507 was chosen as the SARS-CoV-2 infection dataset from the Biotechnology Information (NCBI) GEO database, while GSE153555 was chosen as the dataset of patients with aortic stenosis (AS). This analysis predicted protein-drug interactions (PDIs) and found therapeutic compounds for AS and COVID-19. RESULTS: One hundred and four DEGs were shared between the two datasets. Researchers built a PPI network to identify 10 hub genes from the network. Researchers discovered that COVID-19 and AS shared certain pathogenic pathways and found a relationship between hub genes and transcription factors and miRNAs, as well as a connection between hub genes and proposed treatments. CONCLUSION: Hub genes were identified as potential pathogenic pathways in SARS-CoV-2 infection and AS. In addition, new prescription medication options for treating both illnesses were provided. KEY WORDS: SARS-CoV-2 infection, COVID-19, Aortic stenosis, Differentially expressed genes, Hub genes, Gene-disease, Drug molecule.


Subject(s)
Aortic Valve Stenosis , COVID-19 , MicroRNAs , Humans , SARS-CoV-2 , China , Aortic Valve Stenosis/epidemiology , Aortic Valve Stenosis/genetics , Computational Biology
15.
Front Microbiol ; 14: 1267196, 2023.
Article in English | MEDLINE | ID: mdl-38029082

ABSTRACT

In Phi29-α-hemolysin (α-HL) nanopore sequencing systems, a strong electrochemical signal is dependent on a high concentration of salt. However, high salt concentrations adversely affect polymerase activity. Sequencing by synthesis (SBS) requires the use of phi29 polymerase without exonuclease activity to prevent the degradation of modified nucleotide tags; however, the lack of exonuclease activity also affects polymerase processivity. This study aimed to optimize phi29 polymerase for improved salt tolerance and processivity while maintaining its lack of exonuclease activity to meet the requirements of nanopore sequencing. Using salt tolerance compartmentalized self-replication (stCSR) and a microfluidic platform, we obtained 11 mutant sites with enhanced salt tolerance attributes. Sequencing and biochemical analyses revealed that the substitution of conserved amino acids such as G197D, Y369E, T372N, and I378R plays a critical role in maintaining the processivity of exonuclease-deficient phi29 polymerase under high salt conditions. Furthermore, Y369E and T372N have been identified as important determinants of DNA polymerase binding affinity. This study provides insights into optimizing polymerase processability under high-salt conditions for real-time polymerase nanopore sequencing, paving the way for improved performance and applications in nanopore sequencing technologies.

16.
Extremophiles ; 28(1): 1, 2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37906310

ABSTRACT

A single extremely halophilic strain was isolated from salt brine produced when a fresh water lake flooded a large salt mine located beneath the lake. The water that entered this mine contained less than 0.34 M NaCl, but over time, this sealed brine became saturated by Cenozoic age salt (121-125 million-year BCE). The isolated strain requires at least 1.7 M NaCl for survival and grows optimally in 3.1 M NaCl. Therefore, it could not have survived or been present in the waters that flooded this salt mine. The strain grows at a pH range from 6.5 to 9.0 and has a wide tolerance to temperatures from 25 ℃ to at least 60 ℃. The comparison of 16S rRNA and rpoB' genes revealed that strain 1-13-28T is related to Halorubrum tebenquichense DSM 14210T showing 98.6% and 98.1% similarities, respectively. Phylogenetic analyses based on 16S rRNA, rpoB' genes and 122 concatenated archaeal genes show that the strain 1-13-28T consistently forms a cluster with Halorubrum tebenquichense of the genus Halorubrum. Strain 1-13-28T contained sulfated mannosyl glucosyl diether, and the polar lipid profile was identical to those of most Halorubrum species. Based on the overall combination of physiological, phylogenetic, polar lipids and phylogenomic characteristics, strain 1-13-28T (= ATCC 700083T = CGMCC 1.62627T) represents a newly identified species within the genus Halorubrum for which the name Halorubrum hochsteinianum is proposed.


Subject(s)
Halorubrum , Sodium Chloride , Phospholipids , Halorubrum/genetics , RNA, Ribosomal, 16S/genetics , Phylogeny , Base Composition , DNA, Archaeal/genetics , China , Sequence Analysis, DNA
17.
Nat Genet ; 55(9): 1555-1566, 2023 09.
Article in English | MEDLINE | ID: mdl-37666989

ABSTRACT

Parental histones, the carriers of posttranslational modifications, are deposited evenly onto the replicating DNA of sister chromatids in a process dependent on the Mcm2 subunit of DNA helicase and the Pole3 subunit of leading-strand DNA polymerase. The biological significance of parental histone propagation remains unclear. Here we show that Mcm2-mutated or Pole3-deleted mouse embryonic stem cells (ESCs) display aberrant histone landscapes and impaired neural differentiation. Mutation of the Mcm2 histone-binding domain causes defects in pre-implantation development and embryonic lethality. ESCs with biased parental histone transfer exhibit increased epigenetic heterogeneity, showing altered histone variant H3.3 and H3K27me3 patterning at genomic sites regulating differentiation genes. Our results indicate that the lagging strand pattern of H3.3 leads to the redistribution of H3K27me3 in Mcm2-2A ESCs. We demonstrate that symmetric parental histone deposition to sister chromatids contributes to cellular differentiation and development.


Subject(s)
Histones , Mouse Embryonic Stem Cells , Animals , Mice , Histones/genetics , Embryonic Stem Cells , Cell Differentiation/genetics , DNA Helicases
18.
BMJ Open ; 13(9): e070288, 2023 09 21.
Article in English | MEDLINE | ID: mdl-37734885

ABSTRACT

OBJECTIVE: The aim of this study was to explore the experiences and need for social support of Chinese parents after termination of pregnancy for fetal anomalies. DESIGN: A qualitative study using semistructured, in-depth interviews combined with observations. Data were analysed by Claizzi's phenomenological procedure. SETTING: A large, tertiary obstetrics and gynaecology hospital in China. PARTICIPANTS: Using purposive sampling approach, we interviewed 12 couples and three additional women (whose spouses were not present). RESULTS: Four themes were identified from the experiences of parents: the shock of facing reality, concerns surrounding termination of pregnancy, the embarrassment of the two-child policy and the urgent need for social support. CONCLUSION: Parents experienced complicated and intense emotional reactions, had concerns surrounding the termination of pregnancy and an urgent need for social support. Paternal psychological reactions were often neglected by healthcare providers and the fathers, themselves. These findings suggest that both mothers and fathers should receive appropriate support from family, medical staff and peers to promote their physical and psychological rehabilitation.


Subject(s)
Abortion, Induced , Parents , Pregnancy , Female , Humans , Mothers , China , Social Support
19.
Membranes (Basel) ; 13(8)2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37623780

ABSTRACT

N,N-dimethylformamide (DMF) has excellent chemical stability and is widely used as an aprotic polar solvent. In order to reduce production costs and reduce pollution to the surrounding environment, it is necessary to recycle and reuse DMF. Previous research has found that the thin film composite nanofiltration membrane prepared from liquefied walnut shells exhibited a high rejection rate in DMF, but relatively low permeance and mechanical strength. In order to increase permeance without compromising the separation performance, ethylenediamine (EDA) is used as a modifier to graft onto the structure of liquefied walnut shell through the Mannich reaction. Then, modified liquefied walnut shell as an aqueous monomer reacts with trimesoyl chloride (TMC) via the interfacial polymerization method on the EDA-crosslinked polyetherimide (PEI) membrane. The results show that the permeance of the prepared membrane is significantly improved by an order of magnitude, demonstrating a rejection rate of 98% for crystal violet (CV), and a permeance of 3.53 L m-2 h-1 bar-1 in DMF. In conclusion, this study reveals the potential of utilizing liquefied walnut shells as raw materials for preparing high-performance separation membranes and demonstrates that surface modification is a feasible approach to enhance permeance of membranes without sacrificing the rejection rate.

20.
J Infect Chemother ; 29(11): 1046-1053, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37499902

ABSTRACT

BACKGROUND: Tuberculosis (TB) is an infectious disease with high mortality, and mining key genes for TB diagnosis is vital to raise the survival rate of patients. METHODS: The whole microarray datasets GSE83456 (training set) and GSE19444 (validation set) of TB patients were downloaded from the Gene Expression Omnibus (GEO) database. Differential expression was conducted on genes between TB and normal samples (unconfirmed TB) in GSE83456 to yield TB-related differentially expressed genes (DEGs). DEGs were subjected to weighted gene co-expression network analysis (WGCNA) and clustered to form distinct gene modules. The immune scores of 25 kinds of immune cells were obtained by single-sample gene set enrichment analysis (ssGSEA) of TB samples, and Pearson correlation analysis was carried out between the 25 immune scores and diverse gene modules. The gene modules significantly associated with immune cells were retained as Target modules. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on the genes in the modules (p-value <0.05). The protein-protein interaction (PPI) network was established utilizing the STRING database for genes in the Target module, and the selected key genes were intersected with immune-related genes in the ImmPort database. The obtained immune-related module genes were used for subsequent least absolute shrinkage and selection operator (LASSO) regression analysis and diagnostic models were constructed. Finally, the receiver operating characteristic (ROC) curve was utilized to validate the diagnostic model. RESULTS: The turquoise and yellow modules had a high correlation with macrophages. LASSO regression analysis of immune-related genes in TB was carried on to finally construct a 5-gene diagnostic model composed of C5, GRN, IL1B, IL23A, and TYMP. As demonstrated by the ROC curves, the diagnostic efficiency of this diagnostic model was 0.957 and 0.944 in the training and validation sets, respectively. Therefore, the immune-related 5-gene model had a good diagnostic function for TB. CONCLUSION: We identified 5 immune-related diagnostic markers that may play an important role in TB, and verified that this immune-related key gene model had a good diagnostic performance.


Subject(s)
Tuberculosis , Humans , Tuberculosis/diagnosis , Tuberculosis/genetics , Gene Expression Profiling , Databases, Factual
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