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1.
Nature ; 625(7996): 822-831, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37783228

RESUMO

Argonaute (Ago) proteins mediate RNA- or DNA-guided inhibition of nucleic acids1,2. Although the mechanisms used by eukaryotic Ago proteins and long prokaryotic Ago proteins (pAgos) are known, that used by short pAgos remains elusive. Here we determined the cryo-electron microscopy structures of a short pAgo and the associated TIR-APAZ proteins (SPARTA) from Crenotalea thermophila (Crt): a free-state Crt-SPARTA; a guide RNA-target DNA-loaded Crt-SPARTA; two Crt-SPARTA dimers with distinct TIR organization; and a Crt-SPARTA tetramer. These structures reveal that Crt-SPARTA is composed of a bilobal-fold Ago lobe that connects with a TIR lobe. Whereas the Crt-Ago contains a MID and a PIWI domain, Crt-TIR-APAZ has a TIR domain, an N-like domain, a linker domain and a trigger domain. The bound RNA-DNA duplex adopts a B-form conformation that is recognized by base-specific contacts. Nucleic acid binding causes conformational changes because the trigger domain acts as a 'roadblock' that prevents the guide RNA 5' ends and the target DNA 3' ends from reaching their canonical pockets; this disorders the MID domain and promotes Crt-SPARTA dimerization. Two RNA-DNA-loaded Crt-SPARTA dimers form a tetramer through their TIR domains. Four Crt-TIR domains assemble into two parallel head-to-tail-organized TIR dimers, indicating an NADase-active conformation, which is supported by our mutagenesis study. Our results reveal the structural basis of short-pAgo-mediated defence against invading nucleic acids, and provide insights for optimizing the detection of SPARTA-based programmable DNA sequences.


Assuntos
Proteínas Argonautas , Microscopia Crioeletrônica , NAD+ Nucleosidase , Ácidos Nucleicos , Proteínas Argonautas/química , Proteínas Argonautas/metabolismo , Proteínas Argonautas/ultraestrutura , DNA/química , DNA/genética , DNA/metabolismo , DNA/ultraestrutura , Ativação Enzimática , NAD+ Nucleosidase/química , NAD+ Nucleosidase/genética , NAD+ Nucleosidase/metabolismo , NAD+ Nucleosidase/ultraestrutura , Conformação de Ácido Nucleico , Ácidos Nucleicos/metabolismo , Conformação Proteica , RNA Guia de Sistemas CRISPR-Cas , Mutagênese
2.
PLoS Pathog ; 20(5): e1012209, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709723

RESUMO

[This corrects the article DOI: 10.1371/journal.ppat.1003231.].

3.
Development ; 149(13)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698877

RESUMO

Casein kinase 1α (CK1α), acting as one member of the ß-catenin degradation complex, negatively regulates the Wnt/ß-catenin signaling pathway. CK1α knockout usually causes both Wnt/ß-catenin and p53 activation. Our results demonstrated that conditional disruption of CK1α in spermatogonia impaired spermatogenesis and resulted in male mouse infertility. The progenitor cell population was dramatically decreased in CK1α conditional knockout (cKO) mice, while the proliferation of spermatogonial stem cells (SSCs) was not affected. Furthermore, our molecular analyses identified that CK1α loss was accompanied by nuclear stability of p53 protein in mouse spermatogonia, and dual-luciferase reporter and chromatin immunoprecipitation assays revealed that p53 directly targeted the Sox3 gene. In addition, the p53 inhibitor pifithrin α (PFTα) partially rescued the phenotype observed in cKO mice. Collectively, our data suggest that CK1α regulates spermatogenesis and male fertility through p53-Sox3 signaling, and they deepen our understanding of the regulatory mechanism underlying the male reproductive system.


Assuntos
Caseína Quinase Ialfa , Animais , Caseína Quinase Ialfa/metabolismo , Masculino , Camundongos , Fatores de Transcrição SOXB1/metabolismo , Espermatogênese/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo
4.
Nucleic Acids Res ; 51(13): 7053-7070, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37293979

RESUMO

Schlafen11 (SLFN11) is one of the most studied Schlafen proteins that plays vital roles in cancer therapy and virus-host interactions. Herein, we determined the crystal structure of the Sus scrofa SLFN11 N-terminal domain (NTD) to 2.69 Å resolution. sSLFN11-NTD is a pincer-shaped molecule that shares an overall fold with other SLFN-NTDs but exhibits distinct biochemical characteristics. sSLFN11-NTD is a potent RNase cleaving type I and II tRNAs and rRNAs, and with preference to type II tRNAs. Consistent with the codon usage-based translation suppression activity of SLFN11, sSLFN11-NTD cleaves synonymous serine and leucine tRNAs with different efficiencies in vitro. Mutational analysis revealed key determinates of sSLFN11-NTD nucleolytic activity, including the Connection-loop, active site, and key residues essential for substrate recognition, among which E42 constrains sSLFN11-NTD RNase activity, and all nonconservative mutations of E42 stimulated RNase activities. sSLFN11 inhibited the translation of proteins with a low codon adaptation index in cells, which mainly dependent on the RNase activity of the NTD because E42A enhanced the inhibitory effect, but E209A abolished inhibition. Our findings provide structural characterization of an important SLFN11 protein and expand our understanding of the Schlafen family.


Assuntos
Proteínas Nucleares , RNA de Transferência , Ribonucleases , Domínio Catalítico , Mutação , Ribonucleases/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Sus scrofa , Proteínas Nucleares/metabolismo , Animais
5.
Biol Reprod ; 110(2): 246-260, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-37944068

RESUMO

Uterine glands and their secretions are crucial for conceptus survival and implantation in rodents and humans. In mice, the development of uterine gland known as adenogenesis occurs after birth, whereas the adenogenesis in humans initiates from fetal life and completed at puberty. Uterine adenogenesis involves dynamic epithelial cell proliferation, differentiation, and apoptosis. However, it is largely unexplored about the mechanisms governing adenogenesis. CK1α plays important roles in regulating cell division, differentiation, and death, but it is unknown whether CK1α affects adenogenesis. In the current study, uterus-specific CK1α knockout female mice (Csnk1a1d/d) were infertile resulted from lack of uterine glands. Subsequent analysis revealed that CK1α deletion induced massive apoptosis in uterine epithelium by activating GSK3ß, which was confirmed by injections of GSK3ß inhibitor SB216763 to Csnk1a1d/d females, and the co-treatment of SB216763 and CK1 inhibitor d4476 on cultured epithelial cells. Another important finding was that our results revealed CK1α deficiency activated p53, which then blocked the expression of Foxa2, an important factor for glandular epithelium development and function. This was confirmed by that Foxa2 expression level was elevated in p53 inhibitor pifithrin-α injected Csnk1a1d/d mouse uterus and in vitro dual-luciferase reporter assay between p53 and Foxa2. Collectively, these studies reveal that CK1α is a novel factor regulating uterine adenogenesis by inhibiting epithelial cell apoptosis through GSK3ß pathway and regulating Foxa2 expression through p53 pathway. Uncovering the mechanisms of uterine adenogenesis is expected to improve pregnancy success in humans and other mammals.


Assuntos
Indóis , Maleimidas , Proteína Supressora de Tumor p53 , Útero , Gravidez , Animais , Feminino , Camundongos , Humanos , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Útero/metabolismo , Apoptose , Células Epiteliais/metabolismo , Camundongos Knockout , Mamíferos/metabolismo , Fator 3-beta Nuclear de Hepatócito/genética , Fator 3-beta Nuclear de Hepatócito/metabolismo
6.
Nucleic Acids Res ; 50(16): 9470-9489, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35947700

RESUMO

The HAV nonstructural protein 2C is essential for virus replication; however, its precise function remains elusive. Although HAV 2C shares 24-27% sequence identity with other 2Cs, key motifs are conserved. Here, we demonstrate that HAV 2C is an ATPase but lacking helicase activity. We identified an ATPase-independent nuclease activity of HAV 2C with a preference for polyuridylic single-stranded RNAs. We determined the crystal structure of an HAV 2C fragment to 2.2 Å resolution, containing an ATPase domain, a region equivalent to enterovirus 2C zinc-finger (ZFER) and a C-terminal amphipathic helix (PBD). The PBD of HAV 2C occupies a hydrophobic pocket (Pocket) in the adjacent 2C, and we show the PBD-Pocket interaction is vital for 2C functions. We identified acidic residues that are essential for the ribonuclease activity and demonstrated mutations at these sites abrogate virus replication. We built a hexameric-ring model of HAV 2C, revealing the ribonuclease-essential residues clustering around the central pore of the ring, whereas the ATPase active sites line up at the gaps between adjacent 2Cs. Finally, we show the ribonuclease activity is shared by other picornavirus 2Cs. Our findings identified a previously unfound activity of picornavirus 2C, providing novel insights into the mechanisms of virus replication.


Assuntos
Vírus da Hepatite A , Picornaviridae , Proteínas não Estruturais Virais/metabolismo , Vírus da Hepatite A/genética , Vírus da Hepatite A/metabolismo , Replicação Viral/genética , RNA , Picornaviridae/genética , Adenosina Trifosfatases/genética , Ribonucleases , RNA Viral/genética , RNA Viral/metabolismo
7.
BMC Biol ; 21(1): 49, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36882745

RESUMO

BACKGROUND: Ovarian folliculogenesis is a tightly regulated process leading to the formation of functional oocytes and involving successive quality control mechanisms that monitor chromosomal DNA integrity and meiotic recombination. A number of factors and mechanisms have been suggested to be involved in folliculogenesis and associated with premature ovarian insufficiency, including abnormal alternative splicing (AS) of pre-mRNAs. Serine/arginine-rich splicing factor 1 (SRSF1; previously SF2/ASF) is a pivotal posttranscriptional regulator of gene expression in various biological processes. However, the physiological roles and mechanism of SRSF1 action in mouse early-stage oocytes remain elusive. Here, we show that SRSF1 is essential for primordial follicle formation and number determination during meiotic prophase I. RESULTS: The conditional knockout (cKO) of Srsf1 in mouse oocytes impairs primordial follicle formation and leads to primary ovarian insufficiency (POI). Oocyte-specific genes that regulate primordial follicle formation (e.g., Lhx8, Nobox, Sohlh1, Sohlh2, Figla, Kit, Jag1, and Rac1) are suppressed in newborn Stra8-GFPCre Srsf1Fl/Fl mouse ovaries. However, meiotic defects are the leading cause of abnormal primordial follicle formation. Immunofluorescence analyses suggest that failed synapsis and an inability to undergo recombination result in fewer homologous DNA crossovers (COs) in the Srsf1 cKO mouse ovaries. Moreover, SRSF1 directly binds and regulates the expression of the POI-related genes Six6os1 and Msh5 via AS to implement the meiotic prophase I program. CONCLUSIONS: Altogether, our data reveal the critical role of an SRSF1-mediated posttranscriptional regulatory mechanism in the mouse oocyte meiotic prophase I program, providing a framework to elucidate the molecular mechanisms of the posttranscriptional network underlying primordial follicle formation.


Assuntos
Meiose , Prófase Meiótica I , Fatores de Processamento de Serina-Arginina , Animais , Feminino , Camundongos , Processamento Alternativo , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Meiose/genética , Oócitos , Ovário , Fatores de Processamento de Serina-Arginina/genética
8.
Int J Mol Sci ; 25(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338657

RESUMO

Sensitization to HLA can result in allograft loss for kidney transplantation (KT) patients. Therefore, it is required to develop an appropriate desensitization (DSZ) technique to remove HLA-donor-specific anti-HLA antibody (DSA) before KT. The aim of this research was to investigate whether combined use of the IL-6 receptor-blocking antibody, tocilizumab (TCZ), and bone-marrow-derived mesenchymal stem cells (BM-MSCs) could attenuate humoral immune responses in an allo-sensitized mouse model developed using HLA.A2 transgenic mice. Wild-type C57BL/6 mice were sensitized with skin allografts from C57BL/6-Tg (HLA-A2.1)1Enge/J mice and treated with TCZ, BM-MSC, or both TCZ and BM-MSC. We compared HLA.A2-specific IgG levels and subsets of T cells and B cells using flow cytometry among groups. HLA.A2-specific IgG level was decreased in all treated groups in comparison with that in the allo-sensitized control (Allo-CONT) group. Its decrease was the most significant in the TCZ + BM-MSC group. Regarding the B cell subset, combined use of TCZ and BM-MSC increased proportions of pre-pro B cells but decreased proportions of mature B cells in BM (p < 0.05 vs. control). In the spleen, an increase in transitional memory was observed with a significant decrease in marginal, follicular, and long-lived plasma B cells (p < 0.05 vs. control) in the TCZ + BM-MSC group. In T cell subsets, Th2 and Th17 cells were significantly decreased, but Treg cells were significantly increased in the TCZ+BM-MSC group compared to those in the Allo-CONT group in the spleen. Regarding RNA levels, IL-10 and Foxp3 showed increased expression, whereas IL-23 and IFN-γ showed decreased expression in the TCZ + BM-MSC group. In conclusion, combined use of TCZ and BM-MSC can inhibit B cell maturation and up-regulate Treg cells, finally resulting in the reduction of HLA.A2-specific IgG in a highly sensitized mouse model. This study suggests that the combined use of TCZ and BM-MSC can be proposed as a novel strategy in a desensitization protocol for highly sensitized patients.


Assuntos
Anticorpos Monoclonais Humanizados , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Humanos , Camundongos , Animais , Camundongos Endogâmicos C57BL , Linfócitos B , Camundongos Transgênicos , Antígeno HLA-A2/genética , Antígenos HLA/metabolismo , Imunoglobulina G/metabolismo , Células-Tronco Mesenquimais/metabolismo
9.
BMC Nurs ; 23(1): 221, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561710

RESUMO

BACKGROUND: The outbreak of Corona Virus Disease (COVID-19) in 2019 has continued until now, posing a huge threat to the public's physical and mental health, resulting in different degrees of mental health problems. As a vulnerable segment of the public, anxiety is one of the most common mental health problems among COVID-19 patients. Excessive anxiety aggravates the physical and psychological symptoms of COVID-19 patients, which is detrimental to their treatment and recovery, increases financial expenditure, affects family relations, and adds to the medical burden. OBJECTIVE: This study aimed to explore the role of psychological capital and self-esteem in the relationship between insomnia and anxiety, thereby shedding light on the mechanism of the effect of insomnia on anxiety in COVID-19 patients. METHODS: A cross-sectional study was conducted from April to May 2022 in Fangcang hospital in Shanghai, China. The self-administered questionnaires were distributed to 718 COVID-19 patients via cell phone using the Internet platform "Questionnaire Star", which included Athens Insomnia Scale, Psychological Capital Questionnaire, Self-esteem Scale, Self-Rating Anxiety Scale, gender, age, marital status, education. Data analysis was performed using descriptive analysis, independent-samples t-test, one-way analysis of variance, Pearson correlation analysis, ordinary least-squares regression, and bootstrap method. RESULTS: Education background had significant impact on anxiety in COVID-19 patients (F = 7.70, P < 0.001). Insomnia, psychological capital, self-esteem and anxiety were significantly correlated, respectively (P < 0.001). And Regression analysis showed that insomnia had a direct negative predictive effect on psychological capital (ß = -0.70, P < 0.001) and self-esteem (ß = -0.13, P < 0.001). Psychological capital had a direct positive predictive effect on self-esteem (ß = 0.12, P < 0.001). Insomnia had a direct positive predictive effect on anxiety (ß = 0.61, P < 0.001). Both psychological capital and self-esteem had significant negative predictive effects on anxiety (ß = -0.06, P < 0.05; ß = -0.72, P < 0.001). The results showed that the mediating effect of psychological capital and self-esteem was significant, and the mediating effect value was 0.21. First, the indirect effect consisting of insomnia - psychological capital - anxiety was 0.04, showing that psychological capital had a significant mediating effect. Second, the indirect effect consisting of insomnia-self-esteem-anxiety had a value of 0.10, indicating that self-esteem had a significant mediating effect. Third, the indirect effect consisting of insomnia-psychological capital-self-esteem-anxiety had a value of 0.06, suggesting that psychological capital and self-esteem had a significant chain mediating effect between insomnia and anxiety. CONCLUSIONS: Insomnia had a significant positive predictive effect on anxiety. Insomnia was first associated with a decrease in psychological capital, followed by a sequential decrease in self-esteem, which in turn was associated with increased anxiety symptoms in COVID-19 patients. Therefore, focusing on improving the psychological capital and self-esteem of patients can help alleviate the anxiety caused by insomnia in COVID-19 patients. It is recommended that patients and health care professionals increase the psychological capital and Self-esteem of COVID-19 patients through various methods to counter the effects of insomnia on anxiety.

10.
Am J Physiol Gastrointest Liver Physiol ; 324(4): G295-G304, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36749568

RESUMO

Taurine is an end-product of cysteine metabolism, whereas cysteine dioxygenase (CDO) and cysteine sulfinate decarboxylase (CSAD) are key enzymes regulating taurine synthesis. Sex steroids, including estrogens and androgens, are associated with liver physiopathological processes; however, we still do not know whether taurine and sex steroids interact in regulating liver physiology and hepatic diseases, and whether there are sex differences, although our recent study shows that the estrogen is involved in regulating taurine synthesis in mouse liver. The present study was thus proposed to identify whether 17-ß-estradiol and testosterone (T) play their roles by regulating CDO and CSAD expression and taurine synthesis in male mouse liver. Our results demonstrated that testosterone did not have a significant influence on CDO expression but significantly enhanced CSAD, androgen receptor (AR) expressions, and taurine levels in mouse liver, cultured hepatocytes, and HepG2 cells, whereas these effects were abrogated by AR antagonist flutamide. Furthermore, our results showed that testosterone increased CSAD-promoter-luciferase activity through the direct interaction of the AR DNA binding domain with the CSAD promoter. These findings first demonstrate that testosterone acts as an important factor to regulate sulfur amino acid metabolism and taurine synthesis through AR/CSAD signaling pathway. In addition, the in vivo and in vitro experiments showed that 17-ß-estradiol has no significant effects on liver CSAD expression and taurine synthesis in male mice and suggest that the effects of sex steroids on the taurine synthesis in mouse liver have sex differences. These results are crucial for understanding the physiological functions of taurine/androgen and their interacting mechanisms in the liver.NEW & NOTEWORTHY This study demonstrates that testosterone functions to enhance taurine synthesis by interacting with androgen receptor and binding to cysteine sulfinate decarboxylase (CSAD) promoter zone. Whereas estrogen has no significant effects either on liver CSAD expression or taurine synthesis in male mice and suggests that the effects of sex steroids on taurine synthesis in the liver have gender differences. These new findings are the potential for establishing effective protective and therapeutic strategies for liver diseases.


Assuntos
Carboxiliases , Testosterona , Camundongos , Masculino , Feminino , Animais , Testosterona/farmacologia , Receptores Androgênicos/metabolismo , Fígado/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Carboxiliases/farmacologia , Cisteína Dioxigenase/genética , Cisteína Dioxigenase/metabolismo , Estrogênios/metabolismo , Estradiol/farmacologia , Taurina/metabolismo
11.
Small ; : e2307243, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054802

RESUMO

The high cost of noble Pd/Pt required for the oxygen reduction reaction (ORR) in the cathode restricts the wide applications of fuel cells. In this study, the synthesis of a novel Pd3 CuFe0.5 aerogel electrocatalyst is successfully demonstrated using self-assembly and lyophilization techniques, employing a mild reducing agent. The resulting aerogel electrocatalyst exhibits a distinctive 3D network structure, possessing a substantial BET-specific surface area of 75.19 m2  g-1 . It is worth noting that the optimized Pd3 CuFe0.5 aerogel demonstrates exceptional ORR performance with a high half-wave potential of 0.92 V versus RHE, a significant limiting current density of 7.6 mA cm-2 , and the excellent electrocatalytic stability, superior to the reported noble metal electrocatalysts, with the ORR activity decays only 4.9% after 16 000 s. In addition, the Pd3 CuFe0.5 aerogel electrocatalyst shows superior cycling stability for ≈120 h at a charge/discharge current density of 10 mA cm-2 , indicating its promising application in fuel cells. Furthermore, the resulting composite aerogel possesses excellent hydrogen evolution reaction and ethanol oxidation reaction activity. The density functional theory calculations show that the partial oxidation of Pd3 CuFe0.5 aerogel leads to a negative shift of the d-band center, which energetically optimizes the binding strength of *O intermediates, therefore accelerating the ORR activity.

12.
J Transl Med ; 21(1): 138, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814269

RESUMO

OBJECTIVES: To explore the possibility of kidney organoids generated using patient derived human induced pluripotent stem cells (hiPSC) for modeling of Fabry disease nephropathy (FDN). METHODS: First, we generated hiPSC line using peripheral blood mononuclear cells (PBMCs) from two male FD-patients with different types of GLA mutation: a classic type mutation (CMC-Fb-001) and a non-classic type (CMC-Fb-003) mutation. Second, we generated kidney organoids using wild-type (WT) hiPSC (WTC-11) and mutant hiPSCs (CMC-Fb-001 and CMC-Fb-003). We then compared alpha-galactosidase A (α-GalA) activity, deposition of globotriaosylceremide (Gb-3), and zebra body formation under electromicroscopy (EM). RESULTS: Both FD patients derived hiPSCs had the same mutations as those detected in PBMCs of patients, showing typical pluripotency markers, normal karyotyping, and successful tri-lineage differentiation. Kidney organoids generated using WT-hiPSC and both FD patients derived hiPSCs expressed typical nephron markers without structural deformity. Activity of α-GalA was decreased and deposition of Gb-3 was increased in FD patients derived hiPSCs and kidney organoids in comparison with WT, with such changes being far more significant in CMC-Fb-001 than in CMC-Fb-003. In EM finding, multi-lammelated inclusion body was detected in both CMC-Fb-001 and CMC-Fb-003 kidney organoids, but not in WT. CONCLUSIONS: Kidney organoids generated using hiPSCs from male FD patients might recapitulate the disease phenotype and represent the severity of FD according to the GLA mutation type.


Assuntos
Doença de Fabry , Células-Tronco Pluripotentes Induzidas , Nefropatias , Humanos , Masculino , Doença de Fabry/genética , Leucócitos Mononucleares , Rim , Diferenciação Celular , Organoides
13.
Opt Express ; 31(11): 18599-18612, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381569

RESUMO

A clock recovery algorithm (CRA) suitable for non-integer oversampled Nyquist signals with a small roll-off factor (ROF) is appealing to short-reach high-speed inter-datacenter transmission systems which need to cut down the transceiver power consumption and cost by reducing the oversampling factor (OSF) and using cheap low-bandwidth components. However, due to the lack of a suitable timing phase error detector (TPED), CRAs proposed now fail for non-integer OSFs below two and small ROFs close to zero and are not hardware-efficient. To solve these problems, we propose a low-complexity TPED by modifying the time-domain quadratic signal and reselecting the synchronization spectral component. We demonstrate that the proposed TPED, in combination with a piece-wise parabolic (PWP) interpolator, can significantly improve the performance of feedback CRAs for non-integer oversampled Nyquist signals with a small ROF. Numerical simulations and experiments show that, based on the improved CRA, the receiver sensitivity penalty can keep below 0.5 dB when the OSF is reduced from 2 to 1.25 and the ROF is varied from 0.1 to 0.001 for 45 GBaud dual-polarization Nyquist 16QAM signals.

14.
Opt Lett ; 48(16): 4384-4387, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582038

RESUMO

Digital coherent receivers adopting joint clock recovery and adaptive equalization (JCA) can avoid failures of the adaptive equalizer (AEQ) or clock recovery algorithm (CRA) due to clock asynchrony and chromatic dispersion (CD). But in the previous JCA scheme, the AEQ has a heavy computational load as it has to generate two samples per symbol (SPS) for the subsequent timing phase error detector (TPED) which is the core of the CRA. Furthermore, the previous JCA scheme cannot compensate for receiver skew or accommodate Nyquist signals with small roll-off factors (ROFs). These shortcomings hinder its practical applications in ultrahigh-speed short-reach coherent transmission requiring low power consumption, high spectral efficiency, whilst being sensitive to receiver skew. To solve this problem, we propose a new JCA scheme by integrating a two-section real-valued (RV) AEQ with an all-digital feedback CRA based on a baud-rate TPED versatile for different ROFs. Experiments for 61-GBaud dual-polarization (DP) Nyquist 16QAM signals with an ROF of 0.01 show that, compared with the previous JCA scheme, the proposed scheme can reduce the AEQ computational load by about 70% for 10-km transmission, whilst improving the receiver sensitivity by more than 1.7 dB for a receiver skew of 1.5 ps. As far as we know, the proposed JCA scheme is the most comprehensive and efficient solution for ultrahigh-speed short-reach coherent transmission where CD, receiver skew, clock asynchrony, and Nyquist signals with small ROFs have to be dealt with.

15.
Oral Dis ; 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37103670

RESUMO

OBJECTIVE: The temporomandibular joint (TMJ) disc cushions intraarticular stress during mandibular movements. While mechanical overloading is related to cartilage degeneration, the pathogenesis of TMJ disc degeneration is unclear. Here, we determined the regulatory role of mechanoinductive transient receptor potential vanilloid 4 (TRPV4) in mechanical overload-induced TMJ disc degeneration. METHODS: We explored the effect of mechanical overload on the TMJ discs in a rat occlusal interference model in vivo, and by applying sustained compressive force in vitro. TRPV4 inhibition was delivered by small interfering RNA or GSK2193874; TRPV4 activation was delivered by GSK1016790A. The protective effect of TRPV4 inhibition was validated in the rat occlusal interference model. RESULTS: Occlusal interference induced TMJ disc degeneration with enhanced extracellular matrix degradation in vivo and mechanical overload promoted inflammatory responses in the TMJ disc cells via Ca2+ influx with significantly upregulated TRPV4. TRPV4 inhibition reversed mechanical overload-induced inflammatory responses; TRPV4 activation simulated mechanical overload-induced inflammatory responses. Moreover, TRPV4 inhibition alleviated TMJ disc degeneration in the rat occlusal interference model. CONCLUSION: Our findings suggest TRPV4 plays a pivotal role in the pathogenesis of mechanical overload-induced TMJ disc degeneration and may be a promising target for the treatment of degenerative changes of the TMJ disc.

16.
Anim Biotechnol ; 34(4): 1196-1208, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34939903

RESUMO

Fibroblast growth factor 1(FGF1) has been proved to bind to specific signal molecules and activate intracellular signal transduction, leading to proliferation or differentiation of cells. However, the role of FGF1 in goat adipocytes is still unclear. Here, we investigated its role in lipogenesis of goats, which depends on the activation of FGFRs. In goat intramuscular and subcutaneous adipocytes, we observed that adipocytes accumulation was inhibited by interfering of FGF1, the expression of C/EBPα, C/EBPß, LPL, Pref-1, PPARγ, AP2, KLF4, KLF6, KLF10 and KLF17 were significantly down-regulated (p < 0.05). When the FGF1 was up-regulated, the opposite result was found, while the expression of C/EBPß, LPL, PPARγ, SREBP1, AP2, KLF4, KLF7, KLF15, KLF16 and KLF17 were increased significantly (p < 0.05) in goat intramuscular and subcutaneous adipocytes. The expression level of FGFR1 was significantly and decreased with the interference of FGF1, and increased with the overexpression of FGF1. But in goat subcutaneous adipocytes, only the expression of FGFR2 was consistent with the expression of FGF1. Interference methods confirmed that FGFR1 or FGFR2 and FGF1 have the similarly promoting function in adipocytes differentiation. With the co-transfection technology, we confirmed that FGF1 promoted the differentiation of intramuscular and subcutaneous adipocytes might via FGFR1 or FGFR2, respectively.


Assuntos
Fator 1 de Crescimento de Fibroblastos , Cabras , Animais , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/metabolismo , Cabras/fisiologia , PPAR gama/metabolismo , Diferenciação Celular/fisiologia , Adipócitos/fisiologia
17.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108197

RESUMO

Casein kinase 1α (CK1α) is present in multiple cellular organelles and plays various roles in regulating neuroendocrine metabolism. Herein, we investigated the underlying function and mechanisms of CK1α-regulated thyrotropin (thyroid-stimulating hormone (TSH)) synthesis in a murine model. Immunohistochemistry and immunofluorescence staining were performed to detect CK1α expression in murine pituitary tissue and its localization to specific cell types. Tshb mRNA expression in anterior pituitary was detected using real-time and radioimmunoassay techniques after CK1α activity was promoted and inhibited in vivo and in vitro. Relationships among TRH/L-T4, CK1α, and TSH were analyzed with TRH and L-T4 treatment, as well as thyroidectomy, in vivo. In mice, CK1α was expressed at higher levels in the pituitary gland tissue than in the thyroid, adrenal gland, or liver. However, inhibiting endogenous CK1α activity in the anterior pituitary and primary pituitary cells significantly increased TSH expression and attenuated the inhibitory effect of L-T4 on TSH. In contrast, CK1α activation weakened TSH stimulation by thyrotropin-releasing hormone (TRH) by suppressing protein kinase C (PKC)/extracellular signal-regulated kinase (ERK)/cAMP response element binding (CREB) signaling. CK1α, as a negative regulator, mediates TRH and L-T4 upstream signaling by targeting PKC, thus affecting TSH expression and downregulating ERK1/2 phosphorylation and CREB transcriptional activity.


Assuntos
Caseína Quinases , MAP Quinases Reguladas por Sinal Extracelular , Tireotropina , Animais , Camundongos , Caseína Quinases/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hipófise/metabolismo , Tireotropina/metabolismo , Hormônio Liberador de Tireotropina/metabolismo , Tiroxina/farmacologia
18.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769335

RESUMO

The aim of this study is to explore the possibility of modeling Gitelman's disease (GIT) with human-induced pluripotent stem cell (hiPSC)-derived kidney organoids and to test whether gene correction using CRISPR/Cas9 can rescue the disease phenotype of GIT. To model GIT, we used the hiPSC line CMCi002 (CMC-GIT-001), generated using PBMCs from GIT patients with SLC12A3 gene mutation. Using the CRISPR-Cas9 system, we corrected CMC-GIT-001 mutations and hence generated CMC-GIT-001corr. Both hiPSCs were differentiated into kidney organoids, and we analyzed the GIT phenotype. The number of matured kidney organoids from the CMC-GIT-001corr group was significantly higher, 3.3-fold, than that of the CMC-GIT-001 group (12.2 ± 0.7/cm2 vs. 3.7 ± 0.2/cm2, p < 0.05). In qRT-PCR, performed using harvested kidney organoids, relative sodium chloride cotransporter (NCCT) mRNA levels (normalized to each iPSC) were increased in the CMC-GIT-001corr group compared with the CMC-GIT-001 group (4.1 ± 0.8 vs. 2.5 ± 0.2, p < 0.05). Consistently, immunoblot analysis revealed increased levels of NCCT protein, in addition to other tubular proteins markers, such as LTL and ECAD, in the CMC-GIT-001corr group compared to the CMC-GIT-001 group. Furthermore, we found that increased immunoreactivity of NCCT in the CMC-GIT-001corr group was colocalized with ECAD (a distal tubule marker) using confocal microscopy. Kidney organoids from GIT patient-derived iPSC recapitulated the Gitelman's disease phenotype, and correction of SLC12A3 mutation utilizing CRISPR-Cas9 technology provided therapeutic insight.


Assuntos
Sistemas CRISPR-Cas , Células-Tronco Pluripotentes Induzidas , Humanos , Sistemas CRISPR-Cas/genética , Membro 3 da Família 12 de Carreador de Soluto , Mutação , Rim , Fenótipo , Organoides
19.
Yi Chuan ; 45(10): 922-932, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37872114

RESUMO

This study aimed to assess and compare the performance of different machine learning models in predicting selected pig growth traits and genomic estimated breeding values (GEBV) using automated machine learning, with the goal of optimizing whole-genome evaluation methods in pig breeding. The research employed genomic information, pedigree matrices, fixed effects, and phenotype data from 9968 pigs across multiple companies to derive four optimal machine learning models: deep learning (DL), random forest (RF), gradient boosting machine (GBM), and extreme gradient boosting (XGB). Through 10-fold cross-validation, predictions were made for GEBV and phenotypes of pigs reaching weight milestones (100 kg and 115 kg) with adjustments for backfat and days to weight. The findings indicated that machine learning models exhibited higher accuracy in predicting GEBV compared to phenotypic traits. Notably, GBM demonstrated superior GEBV prediction accuracy, with values of 0.683, 0.710, 0.866, and 0.871 for B100, B115, D100, and D115, respectively, slightly outperforming other methods. In phenotype prediction, GBM emerged as the best-performing model for pigs with B100, B115, D100, and D115 traits, achieving prediction accuracies of 0.547, followed by DL at 0.547, and then XGB with accuracies of 0.672 and 0.670. In terms of model training time, RF required the most time, while GBM and DL fell in between, and XGB demonstrated the shortest training time. In summary, machine learning models obtained through automated techniques exhibited higher GEBV prediction accuracy compared to phenotypic traits. GBM emerged as the overall top performer in terms of prediction accuracy and training time efficiency, while XGB demonstrated the ability to train accurate prediction models within a short timeframe. RF, on the other hand, had longer training times and insufficient accuracy, rendering it unsuitable for predicting pig growth traits and GEBV.


Assuntos
Genoma , Modelos Genéticos , Suínos/genética , Animais , Fenótipo , Genômica/métodos , Genótipo , Polimorfismo de Nucleotídeo Único
20.
Am J Transplant ; 22(6): 1537-1549, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35294797

RESUMO

Sodium/glucose co-transporter-2 inhibitor (SGLT2i) or dipeptidyl peptidase IV inhibitor (DPP4i) is a newer anti-diabetic drug in type II diabetes mellitus (DM), but their use in tacrolimus (TAC)-induced DM is still undetermined. We performed this study to evaluate the effect of these two drugs in TAC-induced DM and nephrotoxicity in ex vivo and in vivo. In the experimental Sprague Dawley rat model of TAC-induced DM and nephrotoxicity, dual inhibition of DPP4 and SGLT2 significantly decreased blood glucose level, HbA1C and increased plasma insulin levels and pancreatic islet size compared with each drug. In the kidney, dual inhibition improved renal function decreased interstitial fibrosis and profibrotic cytokines compared with DPP4i and SGLT2i alone. Increased oxidative stress by TAC was remarkably decreased with DPP4i or SGLT2i in serum, pancreatic and renal tissues and this decrease was much more significant in the combination group. In in vitro study, TAC decreased the cell viability of human kidney-2(HK-2) cells and insulin-secreting beta-cell-derived line(INS-1) cells. SGLT2i protected TAC-induced cell death in HK-2 cells, but not in INS-1 cells. The addition of DPP4i to SGLT2i compensated for a lack of protective effect of SGLT2i on INS-1 cells. This finding provides the rationale for the combined treatment of SGLG2i and DPP4i in TAC-induced DM and nephrotoxicity.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Insulinas , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Hipoglicemiantes/farmacologia , Insulinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Transportador 2 de Glucose-Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Tacrolimo
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