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1.
Proc Natl Acad Sci U S A ; 121(39): e2403222121, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39302967

RESUMEN

Algae mostly occur either as unicellular (microalgae) or multicellular (macroalgae) species, both being uninucleate. There are important exceptions, however, as some unicellular algae are multinucleate and macroscopic, some of which inhabit tropical seas and contribute to biocalcification and coral reef robustness. The evolutionary mechanisms and ecological significance of multinucleation and associated traits (e.g., rapid wound healing) are poorly understood. Here, we report the genome of Halimeda opuntia, a giant multinucleate unicellular chlorophyte characterized by interutricular calcification. We achieve a high-quality genome assembly that shows segregation into four subgenomes, with evidence for polyploidization concomitant with historical sea level and climate changes. We further find myosin VIII missing in H. opuntia and three other unicellular multinucleate chlorophytes, suggesting a potential mechanism that may underpin multinucleation. Genome analysis provides clues about how the unicellular alga could survive fragmentation and regenerate, as well as potential signatures for extracellular calcification and the coupling of calcification with photosynthesis. In addition, proteomic alkalinity shifts were found to potentially confer plasticity of H. opuntia to ocean acidification (OA). Our study provides crucial genetic information necessary for understanding multinucleation, cell regeneration, plasticity to OA, and different modes of calcification in algae and other organisms, which has important implications in reef conservation and bioengineering.


Asunto(s)
Calcificación Fisiológica , Calcificación Fisiológica/genética , Chlorophyta/genética , Chlorophyta/metabolismo , Filogenia , Genoma de Planta , Fotosíntesis/genética
2.
Hum Mol Genet ; 31(9): 1443-1452, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-34791216

RESUMEN

Anomalous pulmonary venous return (APVR) is a potentially lethal congenital heart disease. Elucidating the genetic etiology is crucial for understanding its pathogenesis and improving clinical practice, whereas its genetic basis remains largely unknown because of complex genetic etiology. We thus performed whole-exome sequencing for 144 APVR patients and 1636 healthy controls and report a comprehensive atlas of APVR-related rare genetic variants. Novel singleton, loss-of-function and deleterious missense variants (DVars) were enriched in patients, particularly for genes highly expressed in the developing human heart at the critical time point for pulmonary veins draining into the left atrium. Notably, PLXND1, encoding a receptor for semaphorins, represents a strong candidate gene of APVR (adjusted P = 1.1e-03, odds ratio: 10.9-69.3), accounting for 4.17% of APVR. We further validated this finding in an independent cohort consisting of 82 case-control pairs. In these two cohorts, eight DVars were identified in different patients, which convergently disrupt the GTPase-activating protein-related domain of PLXND1. All variant carriers displayed strikingly similar clinical features, in that all anomalous drainage of pulmonary vein(s) occurred on the right side and incorrectly connected to the right atrium, which may represent a novel subtype of APVR for molecular diagnosis. Studies in Plxnd1 knockout mice further revealed the effects of PLXND1 deficiency on severe heart and lung defects and cellular abnormalities related to APVR such as abnormal migration and vascular formation of vascular endothelial cells. These findings indicate the important role of PLXND1 in APVR pathogenesis, providing novel insights into the genetic etiology and molecular subtyping for APVR.


Asunto(s)
Cardiopatías Congénitas , Venas Pulmonares , Síndrome de Cimitarra , Animales , Células Endoteliales , Atrios Cardíacos , Cardiopatías Congénitas/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Glicoproteínas de Membrana , Ratones , Venas Pulmonares/anomalías , Síndrome de Cimitarra/genética
3.
Chembiochem ; 25(3): e202300781, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38117648

RESUMEN

Heterogeneous chemoenzymatic catalysts differing in their spatial organization and relative orientation of their enzymatic laccase and Pd units confined into macrocellular silica foams were tested on veratryl alcohol oxidation. When operating under continuous flow, we show that the catalytic efficiency of hybrids is significantly enhanced when the Pd(II) complex is combined with a laccase exhibiting a surface located lysine next to the T1 oxidation site of the enzyme.


Asunto(s)
Lacasa , Lacasa/metabolismo , Oxidación-Reducción , Conformación Molecular
4.
J Exp Bot ; 75(20): 6228-6243, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39126383

RESUMEN

Unlike early land plants, flowering plants have evolved a pollen tube that transports a pair of non-motile sperm cells to the female gametophyte. This process, known as siphonogamy, was first observed in gymnosperms and later became prevalent in angiosperms. However, the precise molecular mechanisms underlying the male-female interactions remain enigmatic. From the landing of the pollen grain on the stigma to gamete fusion, the male part needs to pass various tests: how does the stigma distinguish between compatible and incompatible pollen? what mechanisms guide the pollen tube towards the ovule? what factors trigger pollen tube rupture? how is polyspermy prevented? and how does the sperm cell ultimately reach the egg? Successful male-female communication is essential for surmounting these challenges, with cysteine-rich peptides (CRPs) playing a pivotal role in this dialogue. In this review, we summarize the characteristics of four distinct classes of CRPs, systematically review recent progress in the role of CRPs in four crucial stages of pollination and fertilization, consider potential applications of this knowledge in crop breeding, and conclude by suggesting avenues for future research.


Asunto(s)
Flores , Péptidos , Polen , Polinización , Polinización/fisiología , Polen/fisiología , Flores/fisiología , Péptidos/metabolismo , Tubo Polínico/fisiología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Cisteína/metabolismo
5.
FASEB J ; 37(5): e22935, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37086094

RESUMEN

Adipose-derived stem cells (ADSCs) enhance fat graft survival by promoting neovascularization. The mechanism that promotes ADSCs differentiation toward pericytes was not known. We treated ADSCs with conditional medium (CM) from endothelial cells (ECs) or human recombinant transforming growth factor ß (TGF-ß) to induce differentiation into pericytes. Pericytes markers, including platelet-derived growth factor receptor ß (PDGFRß), alpha-smooth muscle actin (α-SMA), and desmin, were examined. Pericytes differentiation markers, migration, and their association with ECs were examined in ADSCs transfected with miR-24-3p mimics and inhibitors. Bioinformatics target prediction platforms and luciferase assays were used to investigate whether PDGFRß was directly targeted by miR-24-3p. In vivo, fat mixed with ADSCs transfected with miR-24-3p mimics or inhibitors was implanted subcutaneously on the lower back region of nude mice. Fat grafts were harvested and analyzed at 2, 4, 6, and 8 weeks. Results showed that endogenous TGF-ß derived from CM from EC or human recombinant TGF-ß promoted migration, association with ECs, and induced expression of pericyte markers (PDGFRß, α-SMA, Desmin) in ADSCs. MiR-24-3p directly targeted PDGFRß in ADSCs by lucifer reporter assays. Inhibition of miR-24-3p promoted pericytes differentiation, migration, and association with ECs in ADSCs. Inhibition of miR-24-3p in ADSCs promoted survival, integrity, adipocyte viability, vascularization, pericytes association with ECs, and reduced fibrosis, whereas overexpression of miR-24-3p in ADSCs yielded the opposite results. Collectively, TGF-ß released by ECs induced ADSCs differentiation toward pericytes through miR-24-3p. Downregulation of miR-24-3p in ADSCs induced survival, integrity, adipocyte viability, vascularization, pericytes association with ECs, and reduced fibrosis after fat grafting.


Asunto(s)
MicroARNs , Pericitos , Ratones , Animales , Humanos , Pericitos/metabolismo , Células Endoteliales/metabolismo , Ratones Desnudos , Desmina , Adipocitos/metabolismo , Diferenciación Celular/fisiología , Factor de Crecimiento Transformador beta/metabolismo , Tejido Adiposo/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Células Madre/metabolismo
6.
Bioorg Med Chem Lett ; 102: 129671, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38387690

RESUMEN

Matrine and indole have antibacterial, anticancer, and other biological activities, in order to develop new antibiotics to solve the problem of multi-drug resistant bacteria. In this paper, we synthesized a series of 29 novel matrine derivatives as potential drug candidates by combining indole analogs and matrine. The antibacterial activity of these compounds was evaluated through minimum inhibitory concentration (MIC) assays against five bacterial strains (S. aureus, C. albicans, P. acnes, P. aeruginosa, and E. coli). The obtained results demonstrated promising antibacterial efficacy, particularly for compounds A20 and A18, which exhibited MICs.au values of 0.021 and 0.031 mg/ml, respectively, against S. aureus. Moreover, compounds A20 and A27 displayed remarkable MICc.al values of 2.806 and 4.519 mg/ml, respectively, against C. albicans, surpassing the performance of the clinical antibiotic penicillin G sodium (0.0368 mg/ml) and fluconazole (4.849 mg/ml). These findings underscore the significant bacteriostatic activity of the matrine derivatives. Furthermore, to gain a deeper understanding 3D-QSAR modeling was employed, revealing the critical influence of steric structure, charge distribution, hydrophobic interactions, and hydrogen bonding within the molecular structure on the bacteriostatic activity of the compounds. Additionally, molecular docking simulations shed light on the interaction between compound A20 and bacterial proteins, highlighting the involvement of hydrogen bonding, hydrophobic interactions, and π-π conjugation in the formation of stable complexes that inhibit the normal functioning of the proteins. This comprehensive analysis provided valuable insights into the antibacterial mechanism of the novel matrine derivatives, offering theoretical support for their potential application as antibiotics.


Asunto(s)
Antibacterianos , Matrinas , Antibacterianos/química , Staphylococcus aureus , Escherichia coli , Simulación del Acoplamiento Molecular , Pruebas de Sensibilidad Microbiana , Indoles/farmacología
7.
Planta Med ; 90(11): 876-884, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38876472

RESUMEN

Corydalis yanhusuo, a traditional Chinese medicine, is widely used to treat various pains, and its active ingredients are alkaloids. This study aimed to develop a new type of transdermal gel plaster containing the extract of C. yanhusuo. Studies have shown that Fu'cupping physical permeation-enhancing technique can promote the penetration of alkaloids and improve the efficacy of drugs. A transdermal gel plaster containing the extract of C. yanhusuo was prepared and optimized using an orthogonal experimental design. The skin permeation ability of the gel plaster was studied in vitro, while the anti-inflammatory and analgesic effects of the prepared patch alone or with Fu'cupping physical permeation-enhancing technique were evaluated in a rat model. The formulation of a gel plaster containing C. yanhusuo extract was successfully prepared with an optimized composition consisting of glycerin (15 g), sodium polyacrylate (2 g), silicon dioxide (0.3 g), ethanol (2 g), aluminum oxide (0.1 g), citric acid (0.05 g), the C. yanhusuo extract (3 g), and water (15 g). The cumulative transdermal permeation of dehydrocorydaline, corypalmine, tetrahydropalmatine, and corydaline in 24 h was estimated to be 569.7 ± 63.2, 74.5 ± 13.7, 82.4 ± 17.2, and 38.9 ± 8.1 µg/cm2, respectively. The in vitro diffusion of dehydrocorydaline and corydaline followed the zero-order kinetics profile, while that of corypalmine and tetrahydropalmatine followed a Higuchi equation. The prepared gel plaster significantly reduced paw swelling, downregulated inflammatory cytokines, and mitigated pain induced by mechanical or chemical stimuli. The Fu'cupping physical permeation-enhancing technique further improved the anti-inflammatory and analgesic effects of the patch. The combined application of the Fu'cupping physical permeation-enhancing technique and the alkaloid gel plaster may be effective against inflammation and pain.


Asunto(s)
Corydalis , Geles , Ratas Sprague-Dawley , Absorción Cutánea , Corydalis/química , Animales , Ratas , Masculino , Administración Cutánea , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Analgésicos/administración & dosificación , Alcaloides/química , Alcaloides/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/administración & dosificación , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Piel/efectos de los fármacos , Permeabilidad
8.
BMC Public Health ; 24(1): 1930, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026282

RESUMEN

OBJECTIVE: To analyse the influencing factors of vaccine hesitancy on HPV vaccination willingness of female college students in order to promote the promotion of HPV vaccine in female college student population. METHODS: From September-October 2022, a convenience sampling method was used to conduct a questionnaire survey among freshman female students from four higher vocational colleges in Henan Province, China. The survey comprised a general information questionnaire, as well as inquiries regarding vaccine hesitancy and willingness to receive the human papillomavirus (HPV) vaccine. In PSM analyses, vaccine-hesitant students were matched with non-vaccine-hesitant students at a 1:1 ratio; subsequently, both univariate and multivariatble logistic regression analyses were applied to assess the impact of vaccine hesitancy on female university students' willingness to receive the HPV vaccine. RESULTS: The results revealed a vaccine hesitancy rate of 44.75% among female university students, with 82.9% expressing willingness to receive the HPV vaccine. The results of the multivariable ordinal logistic regression analysis indicated vaccine hesitancy is a risk factor for HPV vaccination intentions among female university students [OR = 4.38, 95% CI (2.74, 6.99), P < 0.001]. Furthermore, the field of study (P = 0.01) and independently seeking information about the HPV vaccine (P = 0.04) were identified as factors influencing female university students' willingness to receive the HPV vaccine. CONCLUSIONS: Non-vaccine-hesitant students were more likely to be willing to receive the HPV vaccine than vaccine-hesitant students. Healthcare providers and educators should focus on vaccine attitudes among female college students to reduce vaccine hesitancy and enhance community education on cervical cancer, HPV infection and prevention through multichannel campaigns.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Aceptación de la Atención de Salud , Estudiantes , Vacilación a la Vacunación , Humanos , Femenino , China , Vacunas contra Papillomavirus/administración & dosificación , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Estudios Transversales , Adulto Joven , Universidades , Aceptación de la Atención de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/psicología , Infecciones por Papillomavirus/prevención & control , Encuestas y Cuestionarios , Vacilación a la Vacunación/psicología , Vacilación a la Vacunación/estadística & datos numéricos , Adolescente , Conocimientos, Actitudes y Práctica en Salud , Adulto
9.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34810252

RESUMEN

Vascular endothelial cells are exposed to shear stresses with disturbed vs. laminar flow patterns, which lead to proinflammatory vs. antiinflammatory phenotypes, respectively. Effective treatment against endothelial inflammation and the consequent atherogenesis requires the identification of new therapeutic molecules and the development of drugs targeting these molecules. Using Connectivity Map, we have identified vitexin, a natural flavonoid, as a compound that evokes the gene-expression changes caused by pulsatile shear, which mimics laminar flow with a clear direction, vs. oscillatory shear (OS), which mimics disturbed flow without a clear direction. Treatment with vitexin suppressed the endothelial inflammation induced by OS or tumor necrosis factor-α. Administration of vitexin to mice subjected to carotid partial ligation blocked the disturbed flow-induced endothelial inflammation and neointimal formation. In hyperlipidemic mice, treatment with vitexin ameliorated atherosclerosis. Using SuperPred, we predicted that apurinic/apyrimidinic endonuclease1 (APEX1) may directly interact with vitexin, and we experimentally verified their physical interactions. OS induced APEX1 nuclear translocation, which was inhibited by vitexin. OS promoted the binding of acetyltransferase p300 to APEX1, leading to its acetylation and nuclear translocation. Functionally, knocking down APEX1 with siRNA reversed the OS-induced proinflammatory phenotype, suggesting that APEX1 promotes inflammation by orchestrating the NF-κB pathway. Animal experiments with the partial ligation model indicated that overexpression of APEX1 negated the action of vitexin against endothelial inflammation, and that endothelial-specific deletion of APEX1 ameliorated atherogenesis. We thus propose targeting APEX1 with vitexin as a potential therapeutic strategy to alleviate atherosclerosis.


Asunto(s)
Apigenina/genética , Apigenina/fisiología , ADN-(Sitio Apurínico o Apirimidínico) Liasa/genética , Células Endoteliales/metabolismo , Transporte Activo de Núcleo Celular , Animales , Aterosclerosis , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Inflamación , Ratones , Fenotipo , Fosforilación , Unión Proteica , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Factores de Transcripción p300-CBP/metabolismo
10.
Biochem Genet ; 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38581475

RESUMEN

Spinal muscular atrophy (SMA) is a neuromuscular disorder with an autosomal recessive inheritance pattern. Patients with severe symptoms may suffer respiratory failure, leading to death. The homozygous deletion of exon 7 in the SMN1 gene accounts for nearly 95% of all cases. Population carrier screening for SMA and prenatal diagnosis by amniocentesis for high-risk couples can assist in identifying the risk of fetal disease. We provided the SMA carrier screening process to 55,447 pregnant women in Yancheng from October 2020 to December 2022. Among them, 8185 participated in this process, with a participation rate of around 14.76% (95% CI 14.47-15.06%). Quantitative real-time polymerase chain reaction (qPCR) was used to detect deletions of SMN1 exons 7 and 8 (E7, E8) in screened pregnant women. 127 were identified as carriers (111 cases of E7 and E8 heterozygous deletions, 15 cases of E7 heterozygous deletions, and 1 case of E7 heterozygous deletions and E8 homozygous deletions), resulting in a carrying rate of around 1.55% (95% CI 1.30-1.84%). After genetic counseling, 114 spouses of pregnant women who tested positive underwent SMA carrier screening; three of them were screened as SMA carriers. Multiplexed ligation-dependent probe amplification (MLPA) was used for the prenatal diagnosis of the fetuses of high-risk couples. Two of them exhibited two copies of SMN1 exon 7 (normal), and the pregnancy was continued; one exhibited no copies of SMN1 exon 7 and exon 8 (SMA patient), and the pregnancy was terminated. Analyzing SMN1 mutations in Yancheng and provide clinical evidence for SMA genetic counseling and birth defect prevention. Interventional prenatal diagnosis for high-risk families can promote informed reproductive selection and prepare for the fetus's early treatment.

11.
Dev Psychobiol ; 66(5): e22499, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38715454

RESUMEN

Allostatic load (AL) in pregnant women is associated with maternal and infant health outcomes. Whether physical activity (PA) is a modifiable factor associated with AL during pregnancy is unknown. In this cross-sectional study, including 725 pregnant women in 3 different trimesters, 8 biomarkers were included, and the high-risk quartile approach based on sample distribution was used to construct AL index (ALI). ALI <2 was defined as a low level and ≥2 as a high level. Student's t-test or Mann-Whitney U test and chi-squared test or Fisher exact test were used to compare differences in AL with different demographic characteristics among pregnant women. The relationship between PA and AL in pregnant women was analyzed using a binary logistic regression model. The results show that the detection rate of high-risk AL during pregnancy was 47.3%. In the adjusted model, sufficient PA was related to a lower AL than insufficient PA (OR = .693, 95%CI:.494,.971; p = .033). Compared with low- and high-intensity PAs, moderate-intensity PA was associated with lower AL (OR = .645, 95%CI:.447,.930; p = .019). The results suggest that PA is a modifiable factor related to AL, and intervention is recommended to be carried out in the first trimester to prevent the increased likelihood of high AL as pregnancy progresses. In addition, health care personnel should encourage pregnant women to participate in PA, especially moderate-intensity PA, in order to obtain lower AL and promote maternal and child health.


Asunto(s)
Alostasis , Ejercicio Físico , Humanos , Femenino , Embarazo , Alostasis/fisiología , Adulto , Ejercicio Físico/fisiología , Estudios Transversales , Adulto Joven
12.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38542332

RESUMEN

Colorectal cancer (CRC), a prevalent malignant tumor of the digestive system, ranks as the third and second in global incidence and mortality, respectively, in 2020, with 1.93 million new cases (≈10% of all cancers). There are 940,000 deaths (≈9.4% of all cancers), and the incidence of CRC in younger patients (under 50 years of age) has become a new trend. The pathogenesis of CRC is primarily attributed to a series of genetic and epigenetic abnormalities within normal colonic epithelial cells, coupled with the reshaping of the tumor microenvironment in the surrounding stroma. This process leads to the transformation of colorectal adenomas into invasive adenocarcinomas. Although genetic changes are known to be the primary driving force in the occurrence and progression of CRC, recent research indicates that epigenetic regulation serves as a crucial molecular marker in cancer, playing a significant role in the pathological and physiological control of interactions between genetics and the environment. This review discusses the current global epidemiology of CRC, its risk factors, and preventive treatment strategies. The current study explores the latest advancements in the epigenetic regulation of CRC, including DNA methylation, histone modifications, and non-coding RNAs (ncRNAs). These developments hold potential as screening tools, prognostic biomarkers, and therapeutic targets for CRC.


Asunto(s)
Neoplasias Colorrectales , Epigénesis Genética , Humanos , Pronóstico , Metilación de ADN/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/genética , Biomarcadores , Microambiente Tumoral/genética
13.
Biochem Biophys Res Commun ; 639: 91-99, 2023 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-36476951

RESUMEN

The Transmembrane Carboxyl Terminal Domain (TMD) of some Bcl-2 family proteins has been demonstrated to play a key role in modulating apoptosis. We here ustilzed live-cell fluorescence imaging to evaluate how the Bcl-xL TMD (XT) regulate apoptosis. Cell viability assay revealed that XT had strong anti-apoptotic ability similarly to the full-length Bcl-xL. Fluorescence images of living cells co-expressing CFP-XT and Bad-YFP or YFP-Bax revealed that XT recruited Bad to mitochondria but prevented Bax translocation to mitochondria, and also significantly suppressed Bad/Bax-mediated apoptosis, indicating that XT prevents the pro-apoptotic function of Bad and Bax. Fluorescence Resonance Energy Transfer (FRET) analyses determined that XT directly interacted with Bad and Bax, and deletion of XT completely eliminated the mitochondrial localization and homo-oligomerization of Bcl-xL. Fluorescence images of living cells co-expressing CFP-XT and YFP-Bax revealed that XT significantly prevented mitochondrial Bax oligomerization, resulting in cytosolic Bax distribution. Collectively, XT is necessary for the mitochondrial localization and anti-apoptotic capacity of Bcl-xL, and XT, similarly to the full-length Bcl-xL, forms homo-oligomers on mitochondria to directly interact with Bad and Bax to inhibit their apoptotic functions.


Asunto(s)
Mitocondrias , Proteínas Proto-Oncogénicas c-bcl-2 , Proteína bcl-X/metabolismo , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Mitocondrias/metabolismo , Apoptosis/fisiología
14.
New Phytol ; 238(1): 252-269, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36631970

RESUMEN

High temperature causes devasting effects on many aspects of plant cells and thus enhancing plant heat tolerance is critical for crop production. Emerging studies have revealed the important roles of chromatin modifications in heat stress responses. However, how chromatin is regulated during heat stress remains unclear. We show that heat stress results in heterochromatin disruption coupled with histone hyperacetylation and DNA hypomethylation. Two plant-specific histone deacetylases HD2B and HD2C could promote DNA methylation and relieve the heat-induced heterochromatin decondensation. We noted that most DNA methylation regulated by HD2B and HD2C is lost upon heat stress. HD2B- and HD2C-regulated histone acetylation and DNA methylation are dispensable for heterochromatin maintenance under normal conditions, but critical for heterochromatin stabilization under heat stress. We further showed that HD2B and HD2C promoted DNA methylation through associating with ARGONAUTE4 in nucleoli and Cajal bodies, and facilitating its nuclear accumulation. Thus, HD2B and HD2C act both canonically and noncanonically to stabilize heterochromatin under heat stress. This study not only reveals a novel plant-specific crosstalk between histone deacetylases and key factor of DNA methylation pathway, but also uncovers their new roles in chromatic regulation of plant heat tolerance.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Termotolerancia , Heterocromatina/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Histona Desacetilasas/genética , Cromatina/metabolismo , Metilación de ADN/genética
15.
Phys Chem Chem Phys ; 25(13): 9198-9207, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36919363

RESUMEN

Bi-based materials are promising electrocatalysts for CO2 reduction but one of the key technological hurdles is the design of stable, active and affordable Bi-based catalysts over a wide potential range. Herein, Bi2S3/CNTs nanocomposites are constructed by anchoring bismuth sulfide (Bi2S3) nanorods onto the multiwalled carbon nanotubes (CNTs) and utilizing them in electrocatalytic CO2 reduction. CNTs, as a support, not only guarantee the conductivity and dispersibility of Bi2S3 nanorods but also improve the electrolyte infiltration and optimize the electronic structure of the Bi2S3. As expected, the Bi2S3/CNTs nanocomposite exhibits a faradaic efficiency for HCOO- (FEHCOO-) of 99.3% with a current density of -20.3 mA cm-2 at -0.91 V vs. RHE. The FEHCOO- is stably maintained at over > 91% in a wide potential window from -0.71 V to -1.31 V. Theoretical calculation analyses reveal that the strong interaction between Bi2S3 and CNTs is conductive to decreasing the energy barrier of *OCHO, stabilizing the intermediate *OCHO, and inhibiting the hydrogen evolution reaction. The current study provides an insightful understanding of the mechanism of the CO2 electroreduction reaction, and paves a new way for developing superior and affordable electrocatalysts.

16.
Int J Neurosci ; : 1-6, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37691590

RESUMEN

BACKGROUND: There is a lack of actual and comprehensive data on the detection rate of neuronal surface antibodies in patients with unexplained epilepsy in China. Thus, we attempted to analyze the differences in clinical manifestations, cerebrospinal fluid (CSF) characteristics, seizure types and other aspects of antibody-positive and negative patients, to identify suspected antibody-positive epilepsy patients. METHODS: In total, 137 inpatients with unexplained epilepsy were consecutively included, and neuronal surface antibodies (NSAbs) were detected by serological and/or CSF evaluations. The clinical features and seizure characteristics were analyzed between the NSAb-positive and negative patients. In addition, patients were divided into four groups based on CSF and blood antibody titers. CSF cell count and protein content were analyzed in relation to antibody titers. RESULTS: There were 45 (32.8%) patients tested positive for antibodies. Multivariate analyses revealed that age, mental status changes or memory deterioration, CSF protein, CSF cell count, treatment, days of hospitalization, outcome, duration of symptoms before hospitalization, status epilepticus, and number of antiepileptic drugs were significantly associated with the NSAb-positive group and changes in inflammatory indicators in routine CSF analysis were associated with antibody titers. CONCLUSIONS: A relatively high proportion of patients with unexplained epilepsy have positive NSAbs. Patients with the above clinical characteristics need to be highly suspected of NSAbs positivity and should be tested for antibodies in time to assist treatment. The decrease of CSF cell count and protein content has suggestive value for the decrease of antibody titer, which should be evaluated in the follow-up.

17.
Pharm Dev Technol ; 28(5): 452-459, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37104639

RESUMEN

This study aimed to improve the use of YF8, a matrine derivative obtained through chemical transformation of matrine extracted from Sophora alopecuroides. YF8 has demonstrated improved cytotoxicity compared to matrine, but its hydrophobic nature hinders its application. To overcome this, the lipid prodrug YF8-OA was synthesized by linking oleic acid (OA) to YF8 through an ester bond. Although YF8-OA could self-assemble into unique nanostructures in water, it was not sufficiently stable. To enhance the stability of YF8-OA lipid prodrug nanoparticles (LPs), we employed the strategy of PEGylation using DSPE-mPEG2000 or DSPE-mPEG2000 conjugated with folic acid (FA). This resulted in the formation of uniform spherical nanoparticles with greatly improved stability and a maximum drug load capacity upto 58.63%. Cytotoxicity was evaluated in A549, HeLa, and HepG2 cell lines. The results showed that in HeLa cells, the IC50 value of YF8-OA/LPs with FA-modified PEGylation was significantly lower than that of YF8-OA/LPs modified by PEGylation alone. However, no significant enhancement was observed in A549 and HepG2 cells. In conclusion, the lipid prodrug YF8-OA can form nanoparticles in aqueous solution to address its poor water solubility. Modification with FA resulted in further enhanced cytotoxicity, providing a potential avenue for exerting the antitumor activity of matrine analogs.


Asunto(s)
Antineoplásicos , Nanopartículas , Profármacos , Humanos , Profármacos/farmacología , Profármacos/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Oléico , Células HeLa , Ácido Fólico/química , Lipopolisacáridos , Nanopartículas/química , Antineoplásicos/química
18.
BMC Immunol ; 23(1): 30, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672664

RESUMEN

Human peripheral blood mononuclear cells (PBMCs) originate from hematopoietic stem cells in the bone marrow, which mainly includes lymphocytes (T cells, B cells, and natural killer cells) and monocytes. Cryopreserved PBMCs providing biobank resources are crucial for clinical application or scientific research. Here, we used flow cytometry to explore the influence of long-term cryopreservation on the quality of PBMCs with the aim of providing important evidence for the effective utilization of biobank resources. The PBMCs were isolated from the peripheral blood, which was collected from volunteers in the hospital. After long-term cryopreservation in liquid nitrogen, we analyzed the changes in cell numbers, viability, and multiple subtypes of PBMCs and studied the apoptosis, proliferation, activation, function, and status of T cells in comparison with freshly isolated PBMCs by flow cytometry, and then further tracked the effects of long-term cryopreservation on the same sample. Although the different cell types in the PBMCs dynamically changed compared with those in the freshly isolated samples, PBMC recovery and viability remained stable after long-term cryopreservation, and the number of most innate immune cells (e.g., monocytes and B cells) was significantly reduced compared to that of the freshly isolated PBMCs or long-term cryopreserved PBMCs; more importantly, the proportion of T cell subtypes, apoptosis, proliferation, and functional T cells, except for Tregs, were not affected by long-term cryopreservation. However, the proportions of activated T, naïve T, central memory T, effector T, and effector memory T cells dynamically changed after long-term cryopreservation. This article provides important evidence for the effective utilization of biobank resources. Long-term cryopreserved PBMCs can be partly used as biological resources for clinical research or basic studies, but the effect of cryopreservation on PBMCs should be considered when selecting cell samples, especially in research relating to activating or inhibiting function.


Asunto(s)
Criopreservación , Leucocitos Mononucleares , Apoptosis , Citometría de Flujo , Humanos , Linfocitos
19.
J Cell Sci ; 133(20)2020 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-32958707

RESUMEN

Bcl-2 family proteins, as central players of the apoptotic program, participate in regulation of the mitochondrial network. Here, a quantitative live-cell fluorescence resonance energy transfer (FRET) two-hybrid assay was used to confirm the homo-/hetero-oligomerization of mitofusins 2 and 1 (MFN2 and MFN1), and also demonstrate the binding of MFN2 to MFN1 with 1:1 stoichiometry. A FRET two-hybrid assay for living cells co-expressing CFP-labeled Bcl-XL (an anti-apoptotic Bcl-2 family protein encoded by BCL2L1) and YFP-labeled MFN2 or MFN1 demonstrated the binding of MFN2 or MFN1 to Bcl-XL with 1:1 stoichiometry. Neither MFN2 nor MFN1 bound with monomeric Bax in healthy cells, but both MFN2 and MFN1 bind to punctate Bax (pro-apoptotic Bcl-2 family protein) during apoptosis. Oligomerized Bak (also known as BAK1; a pro-apoptotic Bcl-2 family protein) only associated with MFN1 but not MFN2. Moreover, co-expression of Bcl-XL with MFN2 or MFN1 had the same anti-apoptotic effect as the expression of Bcl-XL alone to staurosporine-induced apoptosis, indicating the Bcl-XL has its full anti-apoptotic ability when complexed with MFN2 or MFN1. However, knockdown of MFN2 but not MFN1 reduced mitochondrial aggregation induced by overexpression of Bcl-XL, indicating that MFN2 but not MFN1 mediates Bcl-XL-induced mitochondrial aggregation.


Asunto(s)
GTP Fosfohidrolasas , Mitocondrias , Apoptosis , GTP Fosfohidrolasas/genética , Células HeLa , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteína bcl-X/genética
20.
Cancer Cell Int ; 22(1): 97, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193632

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. Costimulatory molecules have been proven to be the foundation of immunotherapy. However, the potential roles of costimulatory molecule genes (CMGs) in HCC remain unclear. Our study is aimed to develop a costimulatory molecule-related gene signature that could evaluate the prognosis of HCC patients. METHODS: Based on The Cancer Gene Atlas (TCGA) database, univariate Cox regression analysis was applied in CMGs to identify prognosis-related CMGs. Consensus clustering analysis was performed to stratify HCC patients into different subtypes and compared them in OS. Subsequently, the LASSO Cox regression analysis was performed to construct the CMGs-related prognostic signature and Kaplan-Meier survival curves as well as ROC curve were used to validate the predictive capability. Then we explored the correlations of the risk signature with tumor-infiltrating immune cells, tumor mutation burden (TMB) and response to immunotherapy. The expression levels of prognosis-related CMGs were validated based on qRT-PCR and Human Protein Atlas (HPA) databases. RESULTS: All HCC patients were classified into two clusters based on 11 CMGs with prognosis values and cluster 2 correlated with a poorer prognosis. Next, a prognostic signature of six CMGs was constructed, which was an independent risk factor for HCC patients. Patients with low-risk score were associated with better prognosis. The correlation analysis showed that the risk signature could predict the infiltration of immune cells and immune status of the immune microenvironment in HCC. The qRT-PCR and immunohistochemical results indicated six CMGs with differential expression in HCC tissues and normal tissues. CONCLUSION: In conclusion, our CMGs-related risk signature could be used as a prediction tool in survival assessment and immunotherapy for HCC patients.

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