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1.
Mol Cell ; 77(1): 95-107.e5, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31628042

RESUMEN

GTP cyclohydrolase I (GTPCH), 6-pyruvoyltetrahydropterin synthase (PTPS), and sepiapterin reductase (SR) are sequentially responsible for de novo synthesis of tetrahydrobiopterin (BH4), a known co-factor for nitric oxide synthase (NOS). The implication of BH4-biosynthesis process in tumorigenesis remains to be investigated. Here, we show that PTPS, which is highly expressed in early-stage colorectal cancer, is phosphorylated at Thr 58 by AMPK under hypoxia; this phosphorylation promotes PTPS binding to LTBP1 and subsequently drives iNOS-mediated LTBP1 S-nitrosylation through proximal-coupling BH4 production within the PTPS/iNOS/LTBP1 complex. In turn, LTBP1 S-nitrosylation results in proteasome-dependent LTBP1 protein degradation, revealing an inverse relationship between PTPS pT58 and LTBP1 stability. Physiologically, the repressive effect of PTPS on LTBP1 leads to impaired transforming growth factor ß (TGF-ß) secretion and thereby maintains tumor cell growth under hypoxia. Our findings illustrate a molecular mechanism underlying the regulation of LTBP1-TGF-ß signaling by the BH4-biosynthesis pathway and highlight the specific requirement of PTPS for tumor growth.


Asunto(s)
Proliferación Celular/fisiología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Hipoxia/metabolismo , Proteínas de Unión a TGF-beta Latente/metabolismo , Liasas de Fósforo-Oxígeno/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Óxido Nítrico Sintasa/metabolismo , Fosforilación/fisiología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta/metabolismo
2.
Plant Cell ; 36(5): 1844-1867, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38146915

RESUMEN

Hypothetical chloroplast open reading frames (ycfs) are putative genes in the plastid genomes of photosynthetic eukaryotes. Many ycfs are also conserved in the genomes of cyanobacteria, the presumptive ancestors of present-day chloroplasts. The functions of many ycfs are still unknown. Here, we generated knock-out mutants for ycf51 (sll1702) in the cyanobacterium Synechocystis sp. PCC 6803. The mutants showed reduced photoautotrophic growth due to impaired electron transport between photosystem II (PSII) and PSI. This phenotype results from greatly reduced PSI content in the ycf51 mutant. The ycf51 disruption had little effect on the transcription of genes encoding photosynthetic complex components and the stabilization of the PSI complex. In vitro and in vivo analyses demonstrated that Ycf51 cooperates with PSI assembly factor Ycf3 to mediate PSI assembly. Furthermore, Ycf51 interacts with the PSI subunit PsaC. Together with its specific localization in the thylakoid membrane and the stromal exposure of its hydrophilic region, our data suggest that Ycf51 is involved in PSI complex assembly. Ycf51 is conserved in all sequenced cyanobacteria, including the earliest branching cyanobacteria of the Gloeobacter genus, and is also present in the plastid genomes of glaucophytes. However, Ycf51 has been lost from other photosynthetic eukaryotic lineages. Thus, Ycf51 is a PSI assembly factor that has been functionally replaced during the evolution of oxygenic photosynthetic eukaryotes.


Asunto(s)
Proteínas Bacterianas , Sistemas de Lectura Abierta , Complejo de Proteína del Fotosistema I , Synechocystis , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema I/genética , Synechocystis/genética , Synechocystis/metabolismo , Sistemas de Lectura Abierta/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Cloroplastos/metabolismo , Fotosíntesis/genética , Tilacoides/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Complejo de Proteína del Fotosistema II/genética , Mutación
3.
Nucleic Acids Res ; 52(5): 2142-2156, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38340342

RESUMEN

Human DNA topoisomerase 1 (Top1) is a crucial enzyme responsible for alleviating torsional stress on DNA during transcription and replication, thereby maintaining genome stability. Previous researches had found that non-working Top1 interacted extensively with chromosomal DNA in human cells. However, the reason for its retention on chromosomal DNA remained unclear. In this study, we discovered a close association between Top1 and chromosomal DNA, specifically linked to the presence of G-quadruplex (G4) structures. G4 structures, formed during transcription, trap Top1 and hinder its ability to relax neighboring DNAs. Disruption of the Top1-G4 interaction using G4 ligand relieved the inhibitory effect of G4 on Top1 activity, resulting in a further reduction of R-loop levels in cells. Additionally, the activation of Top1 through the use of a G4 ligand enhanced the toxicity of Top1 inhibitors towards cancer cells. Our study uncovers a negative regulation mechanism of human Top1 and highlights a novel pathway for activating Top1.


Asunto(s)
ADN-Topoisomerasas de Tipo I , G-Cuádruplex , Transcripción Genética , Humanos , ADN/química , Replicación del ADN , ADN-Topoisomerasas de Tipo I/metabolismo , Ligandos , Inhibidores de Topoisomerasa I/farmacología
4.
PLoS Pathog ; 19(6): e1011464, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37379354

RESUMEN

Human papillomaviruses (HPV) cause persistent infections by modulating epithelial homeostasis in cells of the infected basal layer. Using FUCCI and cell-cell competition assays, we have identifed regulatory roles for E6AP and NHERF1, which are the primary HPV11 E6 cellular targets, as well as being targets of the high-risk E6 proteins, in processes governing epithelial homeostasis (i.e. cell density, cell cycle entry, commitment to differentiation and basal layer delamination). Depletion of E6AP, or expression of HPV11 or 16E6 increased keratinocyte cell density and cell cycle activity, and delayed the onset of differentiation; phenotypes which were conspicuously present in HPV11 and 16 infected patient tissue. In line with proposed E6 functions, in HPV11 condyloma tissue, E6AP and NHERF1 were significantly reduced when compared to uninfected epithelium. In experimental systems, loss of HPV11 E6/E6AP binding abolished 11E6's homeostasis regulatory functions, while loss of E6/NHERF1 binding reduced the cell density threshold at which differentiation was triggered. By contrast, a NHERF1-binding mutant of 16E6 was not compromised in its homeostasis functions, while E6AP appeared essential. RNA sequencing revealed similar transcriptional profiles in both 11 and 16E6-expressing cells and E6AP-/- cells, with YAP target genes induced, and keratinocyte differentiation genes being downregulated. HPV11 E6-mediated Yap activation was observed in 2D and 3D (organotypic raft) cell culture systems and HPV-infected lesions, with both NHERF1, which is a regulator of the Hippo and Wnt pathways, and E6AP, playing an important role. As the conserved binding partner of Alpha group HPV E6 proteins, the precise role of E6AP in modulating keratinocyte phenotype and associated signalling pathways has not previously been defined. Our study suggests a model in which the preserved functions of the low and high-risk Alpha E6 proteins modulate epithelial homeostasis via E6AP activity, and lead to alteration of multiple downstream pathways, including those involving NHERF1 and YAP.


Asunto(s)
Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Humanos , Virus del Papiloma Humano , Proteínas Represoras/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Papillomaviridae/genética , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Diferenciación Celular , Queratinocitos , Homeostasis
5.
Plant J ; 114(5): 1059-1079, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37029527

RESUMEN

The flexibility of plant growth, development and stress responses is choreographed by an intricate network of signaling cascades and genetic programs. However, it is metabolism that ultimately executes these programs through the selective delivery of specific building blocks and energy. Photosynthetic carbon fixation is the central pillar of the plant metabolic network, the functioning of which is conditioned by environmental fluctuations. Hence, regulation of carbon assimilation metabolism must be particularly versatile and rapid to maintain efficiency and avoid dysfunction. While changes in gene expression can adjust the global inventory and abundance of relevant proteins, their specific characteristics are dynamically altered at the post-translational level. Here we highlight studies that show the extent of the regulatory impact by post-translational modification (PTM) on carbon assimilation metabolism. We focus on examples for which there has been empirical evidence of functional changes associated with a PTM, rather than just the occurrence of PTMs at specific sites in proteins, as regularly detected in proteomic studies. The examples indicate that we are only at the beginning of deciphering the PTM-based regulatory network that operates in plant cells. However, it is becoming increasingly clear that targeted exploitation of PTM engineering has the potential to control the metabolic flux landscape as a prerequisite for increasing crop yields, modifying metabolite composition, optimizing stress tolerance, and even executing novel growth and developmental programs.


Asunto(s)
Carbono , Proteómica , Carbono/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas/metabolismo , Redes y Vías Metabólicas
6.
J Am Chem Soc ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38875215

RESUMEN

We present an efficient one-pot photochemical skeletal editing protocol for the transformation of pyridines into diverse bicyclic pyrazolines and pyrazoles under mild conditions. The method requires no metals, photocatalysts, or additives and allows for the selective removal of specific carbon atoms from pyridines, allowing for unprecedented versatility. Our approach offers a convenient and efficient means for the late-stage modification of complex drug molecules by replacing the core pyridine skeleton. Moreover, we have successfully scaled up this procedure in stop-flow and flow-chemistry systems, showcasing its applicability to intricate transformations such as the Diels-Alder reaction, hydrogenation, [3 + 2] cycloaddition, and Heck reaction. Through control experiments and DFT calculations, we provide insights into the mechanistic underpinnings of this skeletal editing protocol.

7.
Anal Chem ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38315820

RESUMEN

Senescence is an important biological process, which leads to the gradual degradation of its physiological function and increases morbidity and mortality. Herein, a novel ratiometric fluorescent probe (P1) was constructed by using benzothiazolyl acetonitrile dye as fluorophore, exhibiting significantly enhanced blue-shifted emission to indicate the activity of ß-galactosidase (ß-gal), a commonly used biomarker for the detection of senescent cells. After incubation with ß-gal, the excimer emission of P1 at 620 nm was weakened, while the emission at 533 nm was significantly enhanced, forming an obvious ratiometric probe with high sensitivity and low detection limit (2.7 mU·mL-1). More importantly, probe P1 can locate lysosomes accurately, allowing us to monitor the emergence of living cell senescence in real time. P1 was successfully used to detect ß-gal activity in PC-12 cells, Hep G2 cells, and RAW 264.7 cells. It showed strong green fluorescence signal in senescent cells and red fluorescence signal in normal cells, indicating that it can detect endogenous senescence-related ß-gal content in living cells. For in vivo drug-induced senescence imaging, after 5 weeks of injection of D-galactose or hydroxyurea, the mice showed significant fluorescence enhancement in specific channels to indicate the activity of ß-gal in vivo. At the same time, the senescence of cell-specific organs and skin tissues at the organ level were also detected, which proved that the drug-induced senescence of brain, skin, and muscle tissues was the most serious. These results supported the important application value of P1 in senescence biomedical research.

8.
Small ; : e2400740, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693082

RESUMEN

Integrating self-healing capabilities into printed stretchable electronic devices is important for improving performance and extending device life. However, achieving printed self-healing stretchable electronic devices with excellent device-level healing ability and stretchability while maintaining outstanding electrical performance remains challenging. Herein, a series of printed device-level self-healing stretchable electronic devices is achieved by depositing liquid metal/silver fractal dendrites/polystyrene-block-polyisoprene-block-polystyrene (LM/Ag FDs/SIS) conductive inks onto a self-healing thermoplastic polyurethane (TPU) film via screen printing method. Owing to the fluidic properties of the LM and the interfacial hydrogen bonding and disulfide bonds of TPU, the as-obtained stretchable electronic devices maintain good electronic properties under strain and exhibit device-level self-healing properties without external stimulation. Printed self-healing stretchable electrodes possess high electrical conductivity (1.6 × 105 S m-1), excellent electromechanical properties, and dynamic stability, with only a 2.5-fold increase in resistance at 200% strain, even after a complete cut and re-healing treatment. The printed self-healing capacitive stretchable strain sensor shows good linearity (R2 ≈0.9994) in a wide sensing range (0%-200%) and is successfully applied to bio-signal detection. Furthermore, the printed self-healing electronic smart label is designed and can be used for real-time environmental monitoring, which exhibits promising potential for practical application in food preservation packaging.

9.
Chemistry ; : e202402078, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976314

RESUMEN

The functionalization of aromatic N-heterocycles through silylium activation demonstrates exceptional selectivity and efficiency. Density functional theory (DFT) calculations unveil the detailed silylium catalysis mechanism and elucidate the origins of selectivity in this reaction. The phosphoramidimidate sulfonamide (PADI) precatalyst orchestrates of the catalytic cycle via three elementary steps. The Brønsted acidity of precatalyst significantly influences both the formation of silylium-based Lewis acid active species and the silylium activation of pyridine. Unlike disulfonimide (DSI)-type precatalysts, both Tf2NH and PADI precatalysts with strong acidities can easily promote the generation of activated silylium pyridine species. A semi-enclosed 'rigid' electronegative cavity in PADI-type anions constructs a well-defined recognition site, facilitating engagement with the positively charged silylium pyridine species. Due to the high electrophilicity and less steric demand at the C4-position of the pyridine substrate, the product with C4-regioselectivity was predominantly generated.

10.
Thromb J ; 22(1): 29, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509585

RESUMEN

INTRODUCTION: Thrombosis in ANCA-associated vasculitis (AAV) was prevalent and has been neglected in Chinese patients. This study tried to describe the clinical characteristics, identify the risk factors, and investigate the causal relationship between AAV and venous thromboembolism (VTE) by two-sample Mendelian randomization (MR) analysis. METHODS: In this retrospective, observational study, we included all hospitalized AAV patients from Jan 2013 to Apr 2022 in Peking Union Medical College Hospital. We collected their clinical data for multivariate regression analysis to determine the risk factors for thrombosis. The nomogram was constructed by applying these risk factors to predict thrombosis in AAV patients. As for MR analysis, we selected single nucleotide polymorphisms (SNPs) related to AAV from published genome-wide association studies and extracted the outcome data containing deep vein thrombosis (DVT) and pulmonary embolism (PE) from the UK biobank. RESULTS: 1203 primary AAV patients were enrolled, and thrombosis occurred in 11.3%. Multivariate regression suggested that older than 65 years, EGPA, neurological involvement, lung involvement, significantly elevated serum creatinine (> 500µmol/L), and elevated D-dimer were associated with thrombosis in AAV patients. The model demonstrated satisfied discrimination with an AUC of 0.769 (95% CI, 0.726-0.812). MR analysis showed that EGPA could increase the risk of developing DVT and PE (OR = 1.0038, 95%CI = 1.0035-1.0041, P = 0.009). CONCLUSION: Thrombosis was not rare in Chinese patients with AAV. Renal damage and old age emerged as critical risk factors for thrombosis. EGPA might have a potential causal relationship with DVT and PE.

11.
Artículo en Inglés | MEDLINE | ID: mdl-38319470

RESUMEN

PURPOSE: Acute kidney injury (AKI) following anticoagulant application has received growing attention as a significant emerging complication of anticoagulation. Nevertheless, there remains a lack of real-world studies to compare the incidence, clinical features, and prognosis of AKI across different anticoagulant regimens. METHODS: Disproportionality analysis and Bayesian analysis were used to identify suspected AKI cases after different anticoagulant use within the Food and Drug Administration's Adverse Event Reporting System from January 2004 to March 2023. The time to onset, fatality, and hospitalization rates of anticoagulant-associated AKI were also investigated. RESULTS: We identified 9313 anticoagulant-associated AKIs, which appeared to influence mostly patients over 65 years old (65.37%). Lepirudin displayed a stronger AKI association than others, based on the highest reporting odds ratio (ROR = 6.66, 95% CI = 3.97-11.18), proportional reporting ratio (PRR = 6.08, χ2 = 69.12), and empirical Bayes geometric mean (EBGM = 6.08, the lower 90% one-sided CI = 3.95). Warfarin showed the slightest association with AKI in oral anticoagulants, lower than any direct oral anticoagulants excluding apixaban. Edoxaban exhibited the highest potential renal risk among direct oral anticoagulants, with an ROR of 3.32 (95% CI = 2.95-3.72). The median time to AKI onset was 36 (IQR 7-205) days following the initiation of anticoagulation therapy, and most AKI cases occurred within the first month. CONCLUSION: Particular attention should be directed toward monitoring renal function in individuals receiving anticoagulants, including warfarin and direct oral anticoagulants, as well as other anticoagulant agents. This diligence is particularly imperative within the first month after anticoagulant administration for individuals with a tendency for AKI.

12.
Support Care Cancer ; 32(2): 115, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240829

RESUMEN

BACKGROUND AND AIM: Previous studies reported inconsistent results on the prevalence and prognostic implications of frailty among older adults with gastric cancer. This systematic review synthesized available literature pertaining on this topic to establish the prevalence and unfavorable outcomes of frailty in older adults with gastric cancer. METHODS: A comprehensive search was conducted across multiple English databases including PubMed, Cochrane Library, CINAHL, Embase, and Web of Science as well as Chinese databases, namely, CNKI, Wan Fang, and CBM, from inception to July 4, 2023, to identify potential studies. Data related to the incidence of frailty and its unfavorable outcomes in older adults with gastric cancer were extracted. RevMan5.3 and R 4.2.2 were used to evaluate pooled prevalence, hazard ratios (HR), and 95% confidence interval (CI). RESULTS: This review comprehensively selected 13 studies, comprising 9 cohort studies and 4 cross-sectional studies, on 44,117 older adults diagnosed with gastric cancer. The incidence of frailty among older adults with gastric cancer ranged from 10 to 71%. The pooled prevalence of frailty was 29% (95% CI 0.21-0.39). Frailty was found to be associated with an elevated risk of postoperative complications (HR = 1.99, 95% CI 1.45-2.73), prolonged postoperative hospital stay (HR = 2.68, 95% CI 2.38-3.02), likelihood of readmission (HR = 3.28, 95% CI 1.77-6.08), and an increased mortality risk (HR = 1.60, 95% CI 1.36-1.90). CONCLUSIONS: Frailty was associated with a poor prognosis in older adults with gastric cancer. Clinical medical staff should focus on the frailty of older adults with gastric cancer, conduct large-scale, multicenter, and prospective studies and early screening of patients, and provide guidance for the implementation of prevention and treatment strategies.


Asunto(s)
Fragilidad , Neoplasias Gástricas , Humanos , Anciano , Fragilidad/epidemiología , Fragilidad/complicaciones , Anciano Frágil , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/complicaciones , Estudios Prospectivos , Prevalencia , Estudios Transversales , Factores de Riesgo , Estudios Multicéntricos como Asunto
13.
Nucleic Acids Res ; 50(8): e46, 2022 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-35061906

RESUMEN

Given the fact that the localization of RNAs is closely associated with their functions, techniques developed for tracking the distribution of RNAs in live cells have greatly advanced the study of RNA biology. Recently, innovative application of fluorescent protein-labelled Cas9 and Cas13 into live-cell RNA tracking further enriches the toolbox. However, the Cas9/Cas13 platform, as well as the widely-used MS2-MCP technique, failed to solve the problem of high background noise. It was recently reported that CRISPR/Cas6 would exhibit allosteric alteration after interacting with the Cas6 binding site (CBS) on RNAs. Here, we exploited this feature and designed a Cas6-based switch platform for detecting target RNAs in vivo. Conjugating split-Venus fragments to both ends of the endoribonuclease-mutated Escherichia coli Cas6(dEcCas6) allowed ligand (CBS)-activated split-Venus complementation. We name this platform as Cas6 based Fluorescence Complementation (Cas6FC). In living cells, Cas6FC could detect target RNAs with nearly free background noise. Moreover, as minimal as one copy of CBS (29nt) tagged in an RNA of interest was able to turn on Cas6FC fluorescence, which greatly reduced the odds of potential alteration of conformation and localization of target RNAs. Thus, we developed a new RNA tracking platform inherently with high sensitivity and specificity.


Asunto(s)
Endorribonucleasas , ARN , Sitios de Unión , Sistemas CRISPR-Cas , Endorribonucleasas/metabolismo , Fluorescencia , Conformación Molecular , ARN/química
14.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001600

RESUMEN

G-quadruplexes (G4s) formed by guanine-rich nucleic acids play a role in essential biological processes such as transcription and replication. Besides the >1.5 million putative G-4-forming sequences (PQSs), the human genome features >640 million single-nucleotide variations (SNVs), the most common type of genetic variation among people or populations. An SNV may alter a G4 structure when it falls within a PQS motif. To date, genome-wide PQS-SNV interactions and their impact have not been investigated. Herein, we present a study on the PQS-SNV interactions and the impact they can bring to G4 structures and, subsequently, gene expressions. Based on build 154 of the Single Nucleotide Polymorphism Database (dbSNP), we identified 5 million gains/losses or structural conversions of G4s that can be caused by the SNVs. Of these G4 variations (G4Vs), 3.4 million are within genes, resulting in an average load of >120 G4Vs per gene, preferentially enriched near the transcription start site. Moreover, >80% of the G4Vs overlap with transcription factor-binding sites and >14% with enhancers, giving an average load of 3 and 7.5 for the two regulatory elements, respectively. Our experiments show that such G4Vs can significantly influence the expression of their host genes. These results reveal genome-wide G4Vs and their impact on gene activity, emphasizing an understanding of genetic variation, from a structural perspective, of their physiological function and pathological implications. The G4Vs may also provide a unique category of drug targets for individualized therapeutics, health risk assessment, and drug development.


Asunto(s)
Proteínas de Unión al ADN/ultraestructura , G-Cuádruplex , Genoma Humano/genética , Conformación de Ácido Nucleico , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/genética , Humanos , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Sitio de Iniciación de la Transcripción , Activación Transcripcional/genética
15.
BMC Biol ; 21(1): 89, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-37069605

RESUMEN

BACKGROUND: Sperm is formed through spermiogenesis, a highly complex process involving chromatin condensation that results in cessation of transcription. mRNAs required for spermiogenesis are transcribed at earlier stages and translated in a delayed fashion during spermatid formation. However, it remains unknown that how these repressed mRNAs are stabilized. RESULTS: Here we report a Miwi-interacting testis-specific and spermiogenic arrest protein, Ck137956, which we rename Tssa. Deletion of Tssa led to male sterility and absence of sperm formation. The spermiogenesis arrested at the round spermatid stage and numerous spermiogenic mRNAs were down-regulated in Tssa-/- mice. Deletion of Tssa disrupted the localization of Miwi to chromatoid body, a specialized assembly of cytoplasmic messenger ribonucleoproteins (mRNPs) foci present in germ cells. We found that Tssa interacted with Miwi in repressed mRNPs and stabilized Miwi-interacting spermiogenesis-essential mRNAs. CONCLUSIONS: Our findings indicate that Tssa is indispensable in male fertility and has critical roles in post-transcriptional regulations by interacting with Miwi during spermiogenesis.


Asunto(s)
Proteínas Argonautas , Semen , Espermatogénesis , Animales , Masculino , Ratones , Fertilidad/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Semen/metabolismo , Espermatogénesis/genética , Testículo/metabolismo , Proteínas Argonautas/genética
16.
Ren Fail ; 46(1): 2338483, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38604948

RESUMEN

BACKGROUND: Previous study consistently showed that lower serum sodium (SNa) was associated with a greater risk of mortality in hemodialysis (HD) patients. However, few studies have focused on the change in SNa (ΔSNa = post-HD SNa - pre-HD SNa) during an HD session. METHODS: In a retrospective cohort of maintenance HD adults, all-cause mortality and cardio-cerebrovascular event (CCVE) were followed up for a medium of 82 months. Baseline pre-HD SNa and ΔSNa were collected; time-averaged pre-HD SNa and ΔSNa were computed as the mean values within 1-year, 2-year and 3-year intervals after enrollment. Cox proportional hazards models were used to evaluate the relationships of pre-HD and ΔSNa with outcomes. RESULTS: Time-averaged pre-HD SNa were associated with all-cause mortality (2-year pre-HD SNa: HR [95% CI] 0.86 [0.74-0.99], p = 0.042) and CCVE (3-year pre-HD SNa: HR [95% CI] 0.83 [0.72-0.96], p = 0.012) with full adjustment. Time-averaged ΔSNa also demonstrated an association with all-cause mortality (3-year ΔSNa: HR [95% CI] 1.26 [1.03-1.55], p = 0.026) as well as with CCVE (3-year ΔSNa: HR [95% CI] 1.51 [1.21-1.88], p = <0.001) when fully adjusted. Baseline pre-HD SNa and ΔSNa didn't exhibit association with both outcomes. CONCLUSIONS: Lower time-averaged pre-HD SNa and higher time-averaged ΔSNa were associated with a greater risk of all-cause mortality and CCVE in HD patients.


Asunto(s)
Fallo Renal Crónico , Sodio , Adulto , Humanos , Estudios Retrospectivos , Diálisis Renal/efectos adversos , Modelos de Riesgos Proporcionales
17.
Ren Fail ; 46(1): 2295425, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38178377

RESUMEN

AIM: Tripterygium wilfordii Hook F (TwHF) has been shown to substantially reduce proteinuria in patients with diabetic kidney disease (DKD); however, the effect of TwHF on renal outcomes in DKD remains unknown. Accordingly, we aimed to establish the effects of TwHF on renal outcomes in patients with DKD. METHODS: Overall, 124 patients with DKD, induced by type 2 diabetes mellitus, with 24-h proteinuria > 2 g, and an estimated glomerular filtration rate > 30 mL/min/1.73 m2 were retrospectively investigated. The renal outcomes were defined as doubling serum creatinine levels or end-stage kidney disease. Kaplan-Meier curves and Cox regression analyses were performed to analyze prognostic factors for renal outcomes. RESULTS: By the end of the follow-up, renal outcomes were observed in 23 and 11 patients in the non-TwHF and TwHF groups, respectively (p = 0.006). TwHF significantly reduced the risk of renal outcomes (adjusted hazard ratio [HR] 0.271, 95% confidence interval [CI] 0.111-0.660, p = 0.004) in patients with chronic kidney disease (CKD) G3 (adjusted HR 0.274, 95%CI 0.081-0.932, p = 0.039). Based on the Kaplan-Meier analysis, 1- and 3-year proportions of patients without renal outcomes were significantly lower in the non-TwHF group than those in the TwHF group (92.8% vs. 95.5% and 47.2% vs. 76.8%, respectively; p = 0.0018). CONCLUSION: In DKD patients with severe proteinuria, TwHF could prevent DKD progression, especially in patients with CKD G3. A randomized clinical trial is needed to elucidate the benefits of TwHF on renal outcomes in patients with DKD.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Insuficiencia Renal Crónica , Humanos , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/tratamiento farmacológico , Tripterygium , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Estudios Retrospectivos , Proteinuria/tratamiento farmacológico , Proteinuria/etiología
18.
Ren Fail ; 46(1): 2302409, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38275162

RESUMEN

INTRODUCTION: Renal involvement of primary biliary cholangitis (PBC) usually presents as distal renal tubular acidosis. Proximal tubular (PT) dysfunctions in PBC were rarely reported with unclear clinicopathological characteristics and renal prognosis. METHODS: We identified 11 cases of PBC with PT dysfunctions (PBC-PT). Their medical document, kidney pathology, and follow-up data were retrospectively reviewed and analyzed. RESULTS: The 11 PBC-PT patients were mainly middle-aged (57.8 ± 5.2 years) females (81.8%). Most of them were asymptomatic PBC (7, 63.6%) with a high prevalence of elevated serum immunoglobulin M (IgM, 81.8%) and G (IgG, 54.5%) levels. In the kidney, they had a mean estimated glomerular filtration rate (eGFR) level of 46.54 ± 23.03 ml/min/1.73m2, and 81.8% of them had eGFR below 60 ml/min/1.73m2. They showed different degrees of PT dysfunctions, including hyperuricosuria, hypouricemia, normoglycemic glycosuria, generalized aminoaciduria, hyperphosphaturia, and hypophosphatemia. Their kidney pathology showed tubulointerstitial nephritis with lymphoplasmacytic infiltrates, brush border defects, and proximal tubulitis. After glucocorticoids treatment, the PT dysfunctions manifesting as hypophosphatemia, hypouricemia, and renal glycosuria all recovered, and the eGFR levels were improved from 43.24 ± 19.60 ml/min/1.73m2 to 55.02 ± 21.14 ml/min/1.73m2 (p = 0.028), accompanied by significant improvements of serum IgM levels (from 5.97 ± 4.55 g/L to 2.09 ± 1.48 g/L, p = 0.019). CONCLUSIONS: The PT dysfunctions were rare in PBC patients, and glucocorticoids treatment could benefit the improvements of eGFR and tubular functions.


Asunto(s)
Hipofosfatemia , Cirrosis Hepática Biliar , Nefritis Intersticial , Persona de Mediana Edad , Femenino , Humanos , Estudios Retrospectivos , Cirrosis Hepática Biliar/complicaciones , Nefritis Intersticial/patología , Inmunoglobulina M , Hipofosfatemia/complicaciones
19.
Chem Soc Rev ; 52(12): 3991-4005, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37278085

RESUMEN

Surface barriers to mass transfer in various nanoporous materials have been increasingly identified. These past few years especially, a significant impact on catalysis and separations has come to light. Broadly speaking, there are two types of barriers: internal barriers, which affect intraparticle diffusion, and external barriers, which determine the uptake and release rates of molecules into and out of the material. Here, we review the literature on surface barriers to mass transfer in nanoporous materials and describe how the existence and influence of surface barriers has been characterized, aided by molecular simulations and experimental measurements. As this is a complex, evolving research topic, without consensus from the scientific community at the time of writing, we present various current viewpoints, not always in agreement, on the origin, nature, and function of such barriers in catalysis and separation. We also emphasize the need for considering all the elementary steps of the mass transfer process in optimally designing new nanoporous and hierarchically structured adsorbents and catalysts.

20.
BMC Oral Health ; 24(1): 172, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308269

RESUMEN

BACKGROUND: The range of mandibular invasion by a tumour needs to be determined accurately to minimize unnecessary damage to the mandible. This study aimed to compare tumour boundary lines on computed tomography/magnetic resonance (CT/MR) images with those from pathological findings during the preoperative assessment of mandibular invasion by oral squamous cell carcinoma (OSCC). By comparing the methods, the potential of CT/MR for this application could be further elucidated. METHODS: Eight patients with OSCC were imaged with CT/MR, mandibular specimens were collected, and the material site was measured. Haematoxylin-eosin staining was used for histopathological assessment. The presence and boundaries of bone invasion were evaluated. The CT/MR and histopathological boundaries of bone invasion were delineated and merged to compare and calculate the deviation of CT/MR and histopathological boundaries using the Fréchet distance. RESULTS: The mean Fréchet distance between the CT and pathological tumour boundaries was 2.69 mm (standard error 0.46 mm), with a minimum of 1.18 mm, maximum of 3.64 mm, median of 3.10 mm, and 95% confidence interval of 1.40-3.97 mm. The mean Fréchet distance between the tumour boundaries on the MR and pathological images was 3.07 mm (standard error 0.56 mm), with a minimum of 1.53 mm, maximum of 4.74 mm, median of 2.90 mm, and 95% confidence interval of 1.53-4.61 mm. CONCLUSIONS: CT/MR imaging can provide an effective preoperative assessment of mandibular invasion of OSCC. Pathology images can be positioned on CT/MR scans with the help of computer software to improve the accuracy of the findings. The introduction of the Fréchet distance to compare tumour boundary lines is conducive to computer image diagnosis of tumour invasion of jaw boundaries.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Sensibilidad y Especificidad , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Tomografía Computarizada por Rayos X , Imagen por Resonancia Magnética , Neoplasias de Cabeza y Cuello/patología
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