Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.730
Filtrar
1.
Heliyon ; 10(18): e38203, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39381249

RESUMEN

Background: Hemorrhagic events cause numerous deaths annually worldwide, highlighting the urgent need for effective hemostatic drugs. The glucosyloxybenzyl 2-isobutylmalates Control Extract (BSCE) from the orchid plant Bletilla striata (Thunb.) Rchb.f. has demonstrated significant hemostatic activity in both in vitro and in vivo studies. However, the effect and mechanism of BSCE on non-traumatic bleeding remain unclear. Methods: Pulmonary hemorrhage was induced in 40 Sprague-Dawley rats by administering Zingiber officinale Roscoe. for 14 days. These rats were then randomly divided into five groups: model (Mod), positive control (YNBY), and BSCE low, medium, and high-dose groups. An additional 8 rats served as the control group (Con). The BSCE groups received different doses of BSCE for 10 days, while the YNBY group received Yunnan Baiyao suspension. The effects on body weight, food and water intake, red blood cell count (RBC), hemoglobin concentration (HGB), lung tissue pathology, platelet count, coagulation parameters, and fibrinolytic system markers were evaluated. Network pharmacology and molecular docking analyses were also conducted to identify potential targets and pathways involved in BSCE's effects. Results: BSCE treatment significantly improved body weight, food intake, and water consumption in rats with pulmonary hemorrhage. RBC and HGB levels increased significantly in the BSCE medium and high-dose groups compared to the Mod group (P < 0.05). Pathological examination revealed that BSCE reduced lung tissue hemorrhage and inflammation, with improvements in alveolar structure. BSCE also positively affected platelet count, thrombin time (TT), activated partial thromboplastin time (APTT), fibrinogen (FIB) levels, and fibrinolytic markers (D-dimer, PAI-1, and t-PA). Network pharmacology and molecular docking identified key targets such as MMPs, CASPs, and pathways including IL-17 and TNF signaling, suggesting BSCE's involvement in hemostasis and anti-inflammatory processes. Conclusions: BSCE exhibits significant hemostatic and protective effects on Z.officinale-induced pulmonary hemorrhage in rats by improving hematological parameters, reducing lung tissue damage, and modulating the coagulation and fibrinolytic systems. The study provides evidence supporting the potential of BSCE as a therapeutic agent for hemorrhagic diseases, with its efficacy linked to multi-target and multi-pathway interactions.

2.
Sci Adv ; 10(41): eadq7767, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39383216

RESUMEN

One-carbon ring expansion reaction of N-heterocycles has gained particular attention in the past decade because this method allows for the conversion of readily available N-heterocycles into potentially useful complex ring-expanded N-heterocycles, which are inaccessible by traditional methods. However, the catalytic asymmetric variant of this reaction has been rarely reported to date. Herein, we disclose an enantioselective one-carbon ring expansion reaction through chiral copper-catalyzed diyne cyclization, leading to the practical, atom-economic and divergent assembly of an array of valuable chiral N-heterocycles bearing a quaternary stereocenter in generally good to excellent yields with excellent enantioselectivities (up to >99% ee). This protocol represents the first example of asymmetric one-carbon ring expansion reaction of N-heterocycles based on alkynes.

3.
Biol Open ; 13(10)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39373150

RESUMEN

Maternal inheritance of mitochondrial DNA (mtDNA) is a widespread phenomenon in eukaryotes. Our earlier research indicated that sperm mtDNA is removed prior to fertilization in mice, and Endonuclease G (ENDOG) orchestrates the degradation of sperm mitochondria in Caenorhabditis elegans. However, the mechanisms underlying sperm mtDNA disposal in mammals remain poorly understood. To investigate the potential role of ENDOG in sperm mtDNA elimination, we created Endog knockout (Endog-/-) mice. Our findings revealed that Endog-/- mice maintained normal spermatogenesis and fertility. Most strikingly, we detected no substantial discrepancy in sperm mtDNA copy number between Endog-/- and control mice. Furthermore, we noted that sperm mtDNA copy numbers were unchanged in both less motile and motile sperm isolated by Percoll gradient centrifugation from Endog-/- and control mice. Taken together, our results indicate that ENDOG is not essential for spermatogenesis or the elimination of sperm mtDNA in mice.


Asunto(s)
ADN Mitocondrial , Endodesoxirribonucleasas , Ratones Noqueados , Espermatogénesis , Espermatozoides , Animales , Masculino , Espermatogénesis/genética , ADN Mitocondrial/genética , Espermatozoides/metabolismo , Ratones , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/metabolismo , Mitocondrias/metabolismo , Mitocondrias/genética , Fertilidad/genética
4.
Cell Mol Life Sci ; 81(1): 421, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367995

RESUMEN

Cullin-RING ubiquitin ligase 4 (CRL4) is closely correlated with the incidence and progression of ovarian cancer. DDB1- and CUL4-associated factor 13 (DCAF13), a substrate-recognition protein in the CRL4 E3 ubiquitin ligase complex, is involved in the occurrence and development of ovarian cancer. However, its precise function and the underlying molecular mechanism in this disease remain unclear. In this study, we confirmed that DCAF13 is highly expressed in human ovarian cancer and its expression is negatively correlated with the overall survival rate of patients with ovarian cancer. We then used CRISPR/Cas9 to knockout DCAF13 and found that its deletion significantly inhibited the proliferation, colony formation, and migration of human ovarian cancer cells. In addition, DCAF13 deficiency inhibited tumor proliferation in nude mice. Mechanistically, CRL4-DCAF13 targeted Fraser extracellular matrix complex subunit 1 (FRAS1) for polyubiquitination and proteasomal degradation. FRAS1 influenced the proliferation and migration of ovarian cancer cell through induction of the focal adhesion kinase (FAK) signaling pathway. These findings collectively show that DCAF13 is an important oncogene that promotes tumorigenesis in ovarian cancer cells by mediating FRAS1/FAK signaling. Our findings provide a foundation for the development of targeted therapeutics for ovarian cancer.


Asunto(s)
Movimiento Celular , Proliferación Celular , Proteínas de la Matriz Extracelular , Quinasa 1 de Adhesión Focal , Ratones Desnudos , Neoplasias Ováricas , Proteínas de Unión al ARN , Animales , Femenino , Humanos , Ratones , Línea Celular Tumoral , Movimiento Celular/genética , Progresión de la Enfermedad , Quinasa 1 de Adhesión Focal/metabolismo , Quinasa 1 de Adhesión Focal/genética , Regulación Neoplásica de la Expresión Génica , Ratones Endogámicos BALB C , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/genética , Transducción de Señal , Ubiquitinación , Proteínas de Unión al ARN/metabolismo , Proteínas de la Matriz Extracelular/metabolismo
5.
PLoS One ; 19(10): e0306152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39413105

RESUMEN

Previous studies have shown sleep deprivation is increasingly reported as one of the causes of female infertility. However, how and by what relevant mechanisms it affects female fertility remains unclear. In this study, female mice underwent 72 hours of total sleep deprivation (TSD) caused by rotating wheel or 2 different controls: a stationary wheel, or forced movement at night. Even though, there was no significant difference in the number of eggs ovulated by the TSD mice compared to the control groups. Overall levels of estrogen and FSH were lower throughout the estrus cycle. A total of 42 genes showed significant differential expression in GV oocytes after TSD by RNA sequencing (RNA-Seq). These included genes were enriched in gene ontology terms of mitochondrial protein complex, oxidoreductase activity, cell division, cell cycle G1/S phase transition, as well as others. The increased concentrations of reactive oxygen species (ROS) in germinal vesicle (GV) and metaphase II (MII) oocytes from TSD mice were observed, which might be induced by impaired mitochondrial function caused by TSD. The GV oocytes displayed increased mitochondrial DNA (mtDNA) copy number and a significant transient increase in inner mitochondrial membrane potential (Δψm) from the TSD mice probably due to compensatory effect. In contrast, MII oocytes in the TSD group showed a decrease in the mtDNA copy number and a lower Δψm compared with the controls. Furthermore, abnormal distribution of mitochondria in the GV and MII oocytes was also observed in TSD mice, suggesting mitochondrial dysfunction. In addition, abnormal spindle and abnormal arrangement of chromosomes in MII oocytes were markedly increased in the TSD mice compared with the control mice. In conclusion, our results suggest that TSD significantly alters the oocyte transcriptome, contributing to oxidative stress and disrupted mitochondrial function, which then resulted in oocyte defects and impaired early embryo development in female mice.


Asunto(s)
ADN Mitocondrial , Potencial de la Membrana Mitocondrial , Mitocondrias , Oocitos , Estrés Oxidativo , Especies Reactivas de Oxígeno , Privación de Sueño , Animales , Femenino , Oocitos/metabolismo , Ratones , Privación de Sueño/metabolismo , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Fertilidad , Infertilidad Femenina/metabolismo , Infertilidad Femenina/genética , Infertilidad Femenina/etiología , Infertilidad Femenina/patología
6.
Microbiol Spectr ; : e0424823, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39412285

RESUMEN

Given the challenges that SARS-CoV-2 variants have caused in terms of rapid spread and reduced vaccine efficacy, a rapid and cost-effective assay that can detect new and emerging variants is greatly needed worldwide. We have successfully applied the xenonucleic acid-based molecular-clamping technology to develop a multiplex reverse-transcription quantitative real-time PCR assay for SARS-CoV-2 multivariant detection. The assay was used to test 649 nasopharyngeal swab samples that were collected for clinical diagnosis or surveillance. The assay was able to correctly identify all 36 Delta variant samples as it accurately detected the D614G, T478K, and L452R mutations. In addition, the assay was able to correctly identify all 34 Omicron samples by detecting the K417N, T478K, N501Y, and D614G mutations. This technique reliably detects a variety of variants and has an analytical sensitivity of 100 copies/mL. In conclusion, this novel assay can serve as a rapid and cost-effective tool to facilitate large-scale detection of SARS-CoV-2 variants. IMPORTANCE: We have developed a multiplex reverse-transcription quantitative real-time PCR (RT-qPCR) testing platform for the rapid detection of SARS-CoV-2 variants using the xenonucleic acid (XNA)-based molecular-clamping technology. The XNA-based RT-qPCR assay can achieve high sensitivity with a limit of detection of about 100 copies/mL for variant detection which is much better than the next-generation sequencing (NGS) assay. Its turnaround time is about 4 hours with lower cost and a lot of Clinical Laboratory Improvement Amendments (CLIA) labs own the instrument and meet skillset requirements. This assay provides a rapid, reliable, and cost-effective testing platform for rapid detection and monitoring of known and emerging SARS-CoV-2 variants. This testing platform can be adopted by laboratories that perform routine SARS-CoV-2 PCR testing, providing a rapid and cost-effective method in lieu of NGS-based assays, for detecting, differentiating, and monitoring SARS-CoV-2 variants. This assay is easily scalable to any new variant(s) should it emerge.

7.
Fitoterapia ; 179: 106245, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39393711

RESUMEN

The husks of Xanthoceras sorbifolia Bunge have gradually attracted widespread attention in recent years due to the abundant resources and ideal pharmacological activities, with barrigenol-like triterpenoid saponins being its biological constituents. In this study, a feature-based molecular networking (FBMN) was utilized to perform the targeted isolation of triterpenoids. As a result, six undescribed barrigenol-type saponins (1-6) along with fourteen known analogues (7-22) were isolated from the extract of X. sorbifolia husk. Their structures were determined through a comprehensive analysis of NMR and HRMS spectroscopic data. Among them, compounds 1-3 are a specific type of saponin featuring a fucose moiety attached at C-21. The antitumor activities of isolated compounds were evaluated and compounds 7, 9 and 10 showed significant inhibitory activities against A549 and HepG2 cell lines in a dose-dependent manner.

8.
Redox Biol ; 77: 103373, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39357422

RESUMEN

The role of gut microbiome in acute kidney injury (AKI) is increasing recognized. Caloric restriction (CR) has been shown to enhance the resistance to ischemia/reperfusion injury to the kidneys in rodents. Nonetheless, it is unknown whether intestinal microbiota mediated CR protection against ischemic/reperfusion-induced injury (IRI) in the kidneys. Herein, we showed that CR ameliorated IRI-elicited renal dysfunction, oxidative stress, apoptosis, and inflammation, along with enhanced intestinal barrier function. In addition, gut microbiota depletion blocked the favorable effects of CR in AKI mice. 16S rRNA and metabolomics analysis showed that CR enriched the gut commensal Parabacteroides goldsteinii (P. goldsteinii) and upregulated the level of serum metabolite dodecafluorpentan. Intestinal colonization of P. goldsteinii and oral administration of dodecafluorpentan showed the similar beneficial effects as CR in AKI mice. RNA sequencing and experimental data revealed that dodecafluorpentan protected against AKI-induced renal injury by antagonizing oxidative burst and NFκB-induced NLRP3 inflammasome activation. In addition, we screened and found that Hamaudol improved renal insufficiency by boosting the growth of P. goldsteinii. Our results shed light on the role of intestinal microbiota P. goldsteinii and serum metabolites dodecafluorpentan in CR benefits to AKI.

9.
Cell Commun Signal ; 22(1): 488, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39394127

RESUMEN

Vascular calcification (VC) arises from the accumulation of calcium salts in the intimal or tunica media layer of the aorta, contributing to higher risk of cardiovascular events and mortality. Despite this, the mechanisms driving VC remain incompletely understood. We previously described that nesfatin-1 functioned as a switch for vascular smooth muscle cells (VSMCs) plasticity in hypertension and neointimal hyperplasia. In this study, we sought to investigate the role and mechanism of nesfatin-1 in VC. The expression of nesfatin-1 was measured in calcified VSMCs and aortas, as well as in patients. Loss- and gain-of-function experiments were evaluated the roles of nesfatin-1 in VC pathogenesis. The transcription activation of nesfatin-1 was detected using a mass spectrometry. We found higher levels of nesfatin-1 in both calcified VSMCs and aortas, as well as in patients with coronary calcification. Loss-of-function and gain-of-function experiments revealed that nesfatin-1 was a key regulator of VC by facilitating the osteogenic transformation of VSMCs. Mechanistically, nesfatin-1 promoted the de-ubiquitination and stability of BMP-2 via inhibiting the E3 ligase SYTL4, and the interaction of nesfatin-1 with BMP-2 potentiated BMP-2 signaling and induced phosphorylation of Smad, followed by HDAC4 phosphorylation and nuclear exclusion. The dissociation of HDAC4 from RUNX2 elicited RUNX2 acetylation and subsequent nuclear translocation, leading to the transcription upregulation of OPN, a critical player in VC. From a small library of natural compounds, we identified that Curculigoside and Chebulagic acid reduced VC development via binding to and inhibiting nesfatin-1. Eventually, we designed a mass spectrometry-based DNA-protein interaction screening to identify that STAT3 mediated the transcription activation of nesfatin-1 in the context of VC. Overall, our study demonstrates that nesfatin-1 enhances BMP-2 signaling by inhibiting the E3 ligase SYTL4, thereby stabilizing BMP-2 and facilitating the downstream phosphorylation of SMAD1/5/9 and HDAC4. This signaling cascade leads to RUNX2 activation and the transcriptional upregulation of MSX2, driving VC. These insights position nesfatin-1 as a potential therapeutic target for preventing or treating VC, advancing our understanding of the molecular mechanisms underlying this critical cardiovascular condition.


Asunto(s)
Proteína Morfogenética Ósea 2 , Músculo Liso Vascular , Nucleobindinas , Osteogénesis , Transducción de Señal , Calcificación Vascular , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Nucleobindinas/metabolismo , Nucleobindinas/genética , Humanos , Calcificación Vascular/metabolismo , Calcificación Vascular/patología , Calcificación Vascular/genética , Proteína Morfogenética Ósea 2/metabolismo , Animales , Masculino , Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al Calcio/genética , Miocitos del Músculo Liso/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Histona Desacetilasas/metabolismo , Histona Desacetilasas/genética , Aorta/metabolismo , Aorta/patología
10.
Nat Commun ; 15(1): 8786, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39389980

RESUMEN

In a molecule formed by two atoms, energy difference between bonding and antibonding orbitals depends on distance between the two atoms. However, exploring molecular orbitals of two natural atoms with tunable distance has remained an outstanding experimental challenge. Graphene quantum dots can be viewed as relativistic artificial atoms, thus offering a unique platform to study molecular physics. Here, through scanning tunneling microscope, we create and directly visualize the formation process of relativistic artificial molecules based on two coupled graphene quantum dots with tunable distance. Our study indicates that energy difference between the bonding and antibonding orbitals of the lowest quasibound state increases linearly with inverse distance between the two graphene quantum dots due to the relativistic nature of the artificial molecule. For quasibound states with higher orbital momenta, the coupling between these states leads to half-energy spacing of the confined states because the length of the molecular-like orbit is approximately twice that of the atomic-like orbit. Evolution from ring-like whispering-gallery modes in the artificial atoms to figure-eight orbitals in the artificial molecules is directly imaged. The ability to resolve the coupling and orbitals of the relativistic artificial molecule at the nanoscale level yields insights into the behavior of quantum-relativistic matter.

11.
ACS Nano ; 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39418668

RESUMEN

Recently, the rising demand for data-based applications has driven the convergence of image sensing, memory, and computing unit interfaces. While specialized electronic hardware has spurred advancements in the in-memory and in-sensor computing, integrating the entire signal-processing chain into a single device still faces significant challenges. Here, a reconfigurable all-optical controlled memristor with the selector-free feature is demonstrated. The conductance of the device can be controlled within the pure light domain, which enables it to integrate sensing, memory, and computing together. The integrate-and-fire behavior is also realized through electrical stimuli. Furthermore, the device exhibits an excellent rectifying ratio and nonlinearity to overcome the sneak current. Finally, an in-memory sensing and computing architecture is realized through reservoir computing based on neuron and synaptic functions mimicked by the proposed device. Such an all-in-one paradigm facilitates the computing architecture with low energy consumption, low latency, and reduced hardware complexity.

12.
J Basic Microbiol ; : e2400469, 2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39344177

RESUMEN

Monacolin K is a valuable secondary metabolite produced after a period of fermentation by Monascus purpureus; however, our current understanding of the regulatory mechanisms of its synthesis remains incomplete. This study conducted functional analysis on the key transcription factor, comp54181_c0, that is involved in the synthesis of monacolin K in Monascus. Mutant strains with either knockout or overexpression of comp54181_c0 were constructed using CRISPR/Cas9. A comparison between the knockout and overexpression strains revealed changes in fungal morphology and growth, with a significant increase in the production of Monascus pigments and monacolin K when comp54181_c0 was absent. Real-time fluorescence quantitative PCR analysis revealed that comp54181_c0 significantly influenced the transcription of key genes related to monacolin K biosynthesis in Monascus. In conclusion, our study elucidates the crucial role of comp54181_c0 in Monascus, enriches our understanding of fungal secondary metabolite development and regulation, and provides a foundation for the development and regulation of Monascus and monacolin K production.

13.
Molecules ; 29(18)2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39339476

RESUMEN

Poly(N-isopropylacrylamide) (PNIPAM) offers a promising platform for non-invasive and gentle cell detachment. However, conventional PNIPAM-based substrates often suffer from limitations including limited stability and reduced reusability, which hinder their widespread adoption in biomedical applications. In this study, PNIPAM copolymer films were formed on the surfaces of glass slides or silicon wafers using a two-step film-forming method involving coating and grafting. Subsequently, a comprehensive analysis of the films' surface wettability, topography, and thickness was conducted using a variety of techniques, including contact angle analysis, atomic force microscopy (AFM), and ellipsometric measurements. Bone marrow mesenchymal stem cells (BMMSCs) were then seeded onto PNIPAM copolymer films prepared from different copolymer solution concentrations, ranging from 0.2 to 10 mg·mL-1, to select the optimal culture substrate that allowed for good cell growth at 37 °C and effective cell detachment through temperature reduction. Furthermore, the stability and reusability of the optimal copolymer films were assessed. Finally, AFM and X-ray photoelectron spectroscopy (XPS) were employed to examine the surface morphology and elemental composition of the copolymer films after two rounds of BMMSC adhesion and detachment. The findings revealed that the surface properties and overall characteristics of PNIPAM copolymer films varied significantly with the solution concentration. Based on the selection criteria, the copolymer films derived from 1 mg·mL-1 solution were identified as the optimal culture substrates for BMMSCs. After two rounds of cellular adhesion and detachment, some proteins remained on the film surfaces, acting as a foundation for subsequent cellular re-adhesion and growth, thereby implicitly corroborating the practicability and reusability of the copolymer films. This study not only introduces a stable and efficient platform for stem cell culture and harvesting but also represents a significant advance in the fabrication of smart materials tailored for biomedical applications.


Asunto(s)
Resinas Acrílicas , Adhesión Celular , Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Resinas Acrílicas/química , Adhesión Celular/efectos de los fármacos , Técnicas de Cultivo de Célula/métodos , Propiedades de Superficie , Proliferación Celular/efectos de los fármacos , Temperatura , Animales , Microscopía de Fuerza Atómica , Células Cultivadas , Células de la Médula Ósea/citología
14.
Toxicol Lett ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39276810

RESUMEN

Flavopiridol (FP) is a plant-derived flavonoidis and used to treat cancers, fungal infections and inflammation-related diseases. However, it is not clear whether it has side effects on the female reproductive system. In this study, we aimed to investigate the toxic effects and potential underlying mechanisms of FP on oocyte maturation and cumulus cell expansion in mice. Cumulus-oocyte complexes (COCs) were cultured in vitro with FP of gradient concentration (50-1000nM), according to the plasma concentration of FP in the clinical trial. The maturation rate and cumulus expansion index of oocytes were counted and studied by immunofluorescence staining, qRT-PCR, oocyte chromosome preparation and so on. The results showed that the FP-exposed COCs inhibited the oocyte maturation and cumulus cell expansion, leading to cell apoptosis in a dose dependent way. Oocytes exposed to 500nM FP showed abnormalities in the spindle structure and chromosome arrangement, ultimately leading to the oocyte maturation arrest and aneuploidy. This may be due to the excessive oxidative stress caused by mitochondrial membrane potential damage and mislocalization. Therefore, when FP is used for cancer treatment, its side effects on the female reproductive system should be seriously considered.

15.
J Genet Genomics ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39277031

RESUMEN

CtBP-interacting protein (CtIP) is known for its multifaceted roles in DNA repair and genomic stability, directing the homologous recombination-mediated DNA double-stranded break (DSBs) repair pathway via DNA end resection, an essential error-free repair process vital for genome stability. Mammalian oocytes are highly prone to DNA damage accumulation due to prolonged G2/prophase arrest. Here, we explore the functions of CtIP in meiotic cell cycle regulation via a mouse oocyte model. Depletion of CtIP by siRNA injection results in delayed germinal vesicle breakdown and failed polar body extrusion. Mechanistically, CtIP deficiency increases DNA damage and decreases the expression and nuclear entry of CCNB1, resulting in marked impairment of meiotic resumption, which can be rescued by exogenous CCNB1 overexpression. Furthermore, depletion of CtIP disrupts MTOCs coalescence at spindle poles as indicated by failed accumulation of γ-tubulin, p-Aurora kinase A, Kif2A, and TPX2, leading to abnormal spindle assembly and prometaphase arrest. These results provide valuable insights into the important roles of CtIP in the G2/M checkpoint and spindle assembly in mouse oocyte meiotic cell cycle regulation.

16.
Phys Rev Lett ; 133(10): 108001, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39303270

RESUMEN

In the last decade, chirality-induced spin selectivity (CISS) has undergone intensive study. However, there remain several critical issues, such as the microscopic mechanism of CISS, especially transverse CISS where electrons are injected perpendicular to the helix axis of chiral molecules, quantitative agreement between experiments and theory, and at which level the molecular handedness is key to the CISS. Here, we address these issues by performing a combined experimental and theoretical study on conducting polyaniline helical nanofibers which are synthesized in the absence of any chiral species. Large spin polarization is measured in both left- and right-handed nanofibers for electrons injected perpendicular to their helix axis, and it will be reversed by switching the nanofiber handedness. We first develop a theoretical model to study this transverse CISS and quantitatively explain the experiment. Our results reveal that our theory provides a unifying scheme to interpret a number of CISS experiments, quantitative agreement between experiments and numerical calculations can be achieved by weak spin-orbit coupling, and the supramolecular handedness is sufficient for spin selectivity without any chiral species.

17.
Cell Death Dis ; 15(9): 658, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39245708

RESUMEN

In mammalian ovary, the primordial follicle pool serves as the source of developing follicles and fertilizable ova. To maintain the normal length of female reproductive life, the primordial follicles must have adequate number and be kept in a quiescent state before menopause. However, the molecular mechanisms underlying primordial follicle survival are poorly understood. Here, we provide genetic evidence showing that lacking protein phosphatase 4 (PPP4) in oocytes, a member of PP2A-like subfamily, results in infertility in female mice. A large quantity of primordial follicles has been depleted around the primordial follicle pool formation phase and the ovarian reserve is exhausted at about 7 months old. Further investigation demonstrates that depletion of PPP4 causes the abnormal activation of mTOR, which suppresses autophagy in primordial follicle oocytes. The abnormal primordial follicle oocytes are eventually erased by pregranulosa cells in the manner of lysosome invading. These results show that autophagy prevents primordial follicles over loss and PPP4-mTOR pathway governs autophagy during the primordial follicle formation and dormant period.


Asunto(s)
Autofagia , Oocitos , Folículo Ovárico , Fosfoproteínas Fosfatasas , Animales , Femenino , Ratones , Infertilidad Femenina/patología , Infertilidad Femenina/metabolismo , Infertilidad Femenina/genética , Ratones Noqueados , Oocitos/metabolismo , Folículo Ovárico/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Fosfoproteínas Fosfatasas/genética , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
18.
Cell Signal ; 124: 111420, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39304098

RESUMEN

N6-methyladenosine (m6A) is the most common and prevalent internal mRNA modification in eukaryotes. m6A modification is a dynamic and reversible process regulated by methyltransferases, demethylases, and m6A binding proteins. Skin cancers, including melanoma and nonmelanoma skin cancers (NMSCs), are among the most commonly diagnosed cancers worldwide. m6A methylation is involved in the regulation of RNA splicing, translation, degradation, stability, translocation, export, and folding. Aberrant m6A modification participates in the pathophysiological processes of skin cancers and is associated with tumor cell proliferation, invasion, migration, and metastasis during cancer progression. In this review, we provide a comprehensive summary of the biological functions of m6A and the most up-to-date evidence related to m6A RNA modification in skin cancer. We also emphasize the potential clinical applications in the diagnosis and treatment of skin cancers.

19.
Front Public Health ; 12: 1432071, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39281085

RESUMEN

Objective: Osteoarticular tuberculosis (OATB) is one of the most common forms of extrapulmonary tuberculosis; however, limited epidemiological data are available on this public health concern worldwide, especially in developing countries. This study aimed to analyze the clinical epidemiology and drug resistance characteristics of OATB cases in Hunan province which located in South-central China. Methods: We retrospectively enrolled OATB patients with Mycobacterium tuberculosis culture positive at Hunan Chest Hospital from January 2013 through March 31, 2022. The multiple demographic, clinical variables and drug susceptibility data of the patients were collected from the hospital's electronic patient records. Descriptive statistical methods, Chi-square test and logistic regression analysis were employed as statistical methods. Results: Of the 269 OATB cases, 197 (73.23%) were males, 206 (76.85%) were farmers; patients' ages ranged from 5 to 85 years, 57 (21.19%) aged at 20-29 years old and 52 (19.33%) aged at 60-69 years old. In terms of the disease, 177 (65.80%) had spinal TB with most occurrence in lumbar vertebrae (26.02%, 70/269), multiple spinal sites (18.96%, 51/269) and thoracic vertebrae (15.24%, 41/269). Outside of the spine, OATB mainly occurred in the lower limb (13.38%, 36/269). In terms of drug resistance, 40 (14.87%) and 72 (26.77%) were resistant to rifampicin (RFP) and isoniazid (INH) respectively; 38 (14.13%) were multi-drug resistant (MDR), and a total of 78 (29.00%) isolates were drug resistant. OATB patients aged 40-49 years old (compared to those aged ≥70 years) and from the west of Hunan province, China (compared to those from the center of Hunan) were at risk for developing RR/MDR (ORs were 5.057 and 4.942, respectively; 95% CIs were 1.009-25.342 and 1.458-16.750, respectively). Conclusion: In South-central China, OATB mainly affected males, farmers and those aged 20-29 and 60-69 years old. Spinal TB is prone to occur in the lumbar and multiple spinal sites. The resistance situation of OATB was serious, and people aged 40-49 years old and patients from the west of Hunan were risk factors of RR/MDR. All these findings will help to improve the prevention, diagnosis and treatment strategies of OATB.


Asunto(s)
Antituberculosos , Mycobacterium tuberculosis , Tuberculosis Osteoarticular , Humanos , Masculino , Adulto , Persona de Mediana Edad , China/epidemiología , Femenino , Anciano , Adolescente , Niño , Estudios Retrospectivos , Tuberculosis Osteoarticular/epidemiología , Tuberculosis Osteoarticular/tratamiento farmacológico , Tuberculosis Osteoarticular/microbiología , Anciano de 80 o más Años , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Preescolar , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Adulto Joven , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Farmacorresistencia Bacteriana
20.
Neurosurg Rev ; 47(1): 668, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39313739

RESUMEN

Pneumonia is a common postoperative complication in patients with aneurysmal subarachnoid hemorrhage (aSAH), which is associated with poor prognosis and increased mortality. The aim of this study was to develop a predictive model for postoperative pneumonia (POP) in patients with aSAH. A retrospective analysis was conducted on 308 patients with aSAH who underwent surgery at the Neurosurgery Department of the First Affiliated Hospital of Soochow University. Univariate and multivariate logistic regression and lasso regression analysis were used to analyze the risk factors for POP. Receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the constructed model. Finally, the effectiveness of modeling these six variables in different machine learning methods was investigated. In our patient cohort, 23.4% (n = 72/308) of patients experienced POP. Univariate, multivariate logistic regression analysis and lasso regression analysis revealed age, Hunt-Hess grade, mechanical ventilation, leukocyte count, lymphocyte count, and platelet count as independent risk factors for POP. Subsequently, these six factors were used to build the final model. We found that age, Hunt-Hess grade, mechanical ventilation, leukocyte count, lymphocyte count, and platelet count were independent risk factors for POP in patients with aSAH. Through validation and comparison with other studies and machine learning models, our novel predictive model has demonstrated high efficacy in effectively predicting the likelihood of pneumonia during the hospitalization of aSAH patients.


Asunto(s)
Aprendizaje Automático , Neumonía , Complicaciones Posoperatorias , Hemorragia Subaracnoidea , Humanos , Hemorragia Subaracnoidea/cirugía , Hemorragia Subaracnoidea/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Adulto , Factores de Riesgo , Anciano
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA