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1.
FEBS J ; 2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39344089

RESUMEN

Purine-pyrimidine repeats (PPRs) can form left-handed Z-form DNA and induce DNA double-strand breaks (DSBs), posing a risk for genomic rearrangements and cancer. The zinc finger (ZF) and BTB domain-containing protein 43 (ZBTB43) is a transcription factor containing two Cys2-His2 (C2H2) and one C3H1 zinc fingers and plays a crucial role in maintaining genomic and epigenomic integrity by converting mutagenic Z-form PPRs to the B-form in prospermatogonia. Despite its importance, the molecular mechanism underlying the recognition of PPRs by ZBTB43 remains elusive. In this study, we determined the X-ray crystal structure of the ZBTB43 ZF1-3 in complex with the B-form DNA containing the CA repeats sequence. The structure reveals that ZF1 and ZF2 primarily recognize the CACA sequence through specific hydrogen-bonding and van der Waals contacts via a quadruple center involving Arg389, Met411, His413, and His414. These interactions were further validated by fluorescence-based DNA-binding assays using mutated ZBTB43 variants. Our structural investigation provides valuable insights into the recognition mechanism of PPRs by ZBTB43 and suggests a potential role for ZBTB43 in the transformation of Z-DNA to B-DNA, contributing to the maintenance of genomic stability.

2.
JACS Au ; 4(8): 3094-3103, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39211607

RESUMEN

The transcriptional coactivators EP300 and CREBBP are critical regulators of gene expression that share high sequence identity but exhibit nonredundant functions in basal and pathological contexts. Here, we report the development of a bifunctional small molecule, MC-1, capable of selectively degrading EP300 over CREBBP. Using a potent aminopyridine-based inhibitor of the EP300/CREBBP catalytic domain in combination with a VHL ligand, we demonstrate that MC-1 preferentially degrades EP300 in a proteasome-dependent manner. Mechanistic studies reveal that selective degradation cannot be predicted solely by target engagement or ternary complex formation, suggesting additional factors govern paralogue-specific degradation. MC-1 inhibits cell proliferation in a subset of cancer cell lines and provides a new tool to investigate the noncatalytic functions of EP300 and CREBBP. Our findings expand the repertoire of EP300/CREBBP-targeting chemical probes and offer insights into the determinants of selective degradation of highly homologous proteins.

3.
Adv Sci (Weinh) ; 11(35): e2308417, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39041891

RESUMEN

O6-methylguanine DNA methyltransferase (MGMT) removes alkyl adducts from the guanine O6 position (O6-MG) and repairs DNA damage. High MGMT expression results in poor response to temozolomide (TMZ). However, the biological importance of MGMT and the mechanism underlying its high expression in pancreatic neuroendocrine tumors (PanNETs) remain elusive. Here, it is found that MGMT expression is highly elevated in PanNET tissues compared with paired normal tissues and negatively associated with progression-free survival (PFS) time in patients with PanNETs. Knocking out MGMT inhibits cancer cell growth in vitro and in vivo. Ectopic MEN1 expression suppresses MGMT transcription in a manner that depends on ß-Catenin nuclear export and degradation. The Leucine 267 residue of MEN1 is crucial for regulating ß-Catenin-MGMT axis activation and chemosensitivity to TMZ. Interference with ß-Catenin re-sensitizes tumor cells to TMZ and significantly reduces the cytotoxic effects of high-dose TMZ treatment, and MGMT overexpression counteracts the effects of ß-Catenin deficiency. This study reveals the biological importance of MGMT and a new mechanism by which MEN1 deficiency regulates its expression, thus providing a potential combinational strategy for treating patients with TMZ-resistant PanNETs.


Asunto(s)
Metilasas de Modificación del ADN , Enzimas Reparadoras del ADN , Resistencia a Antineoplásicos , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Temozolomida , beta Catenina , Temozolomida/farmacología , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , beta Catenina/metabolismo , beta Catenina/genética , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/metabolismo , Ratones , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Animales , Metilasas de Modificación del ADN/metabolismo , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Línea Celular Tumoral , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Antineoplásicos Alquilantes/farmacología , Modelos Animales de Enfermedad , Masculino , Ratones Desnudos , Femenino
4.
Phys Med Biol ; 69(15)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-38986480

RESUMEN

Objective.Automated detection and segmentation of breast masses in ultrasound images are critical for breast cancer diagnosis, but remain challenging due to limited image quality and complex breast tissues. This study aims to develop a deep learning-based method that enables accurate breast mass detection and segmentation in ultrasound images.Approach.A novel convolutional neural network-based framework that combines the You Only Look Once (YOLO) v5 network and the Global-Local (GOLO) strategy was developed. First, YOLOv5 was applied to locate the mass regions of interest (ROIs). Second, a Global Local-Connected Multi-Scale Selection (GOLO-CMSS) network was developed to segment the masses. The GOLO-CMSS operated on both the entire images globally and mass ROIs locally, and then integrated the two branches for a final segmentation output. Particularly, in global branch, CMSS applied Multi-Scale Selection (MSS) modules to automatically adjust the receptive fields, and Multi-Input (MLI) modules to enable fusion of shallow and deep features at different resolutions. The USTC dataset containing 28 477 breast ultrasound images was collected for training and test. The proposed method was also tested on three public datasets, UDIAT, BUSI and TUH. The segmentation performance of GOLO-CMSS was compared with other networks and three experienced radiologists.Main results.YOLOv5 outperformed other detection models with average precisions of 99.41%, 95.15%, 93.69% and 96.42% on the USTC, UDIAT, BUSI and TUH datasets, respectively. The proposed GOLO-CMSS showed superior segmentation performance over other state-of-the-art networks, with Dice similarity coefficients (DSCs) of 93.19%, 88.56%, 87.58% and 90.37% on the USTC, UDIAT, BUSI and TUH datasets, respectively. The mean DSC between GOLO-CMSS and each radiologist was significantly better than that between radiologists (p< 0.001).Significance.Our proposed method can accurately detect and segment breast masses with a decent performance comparable to radiologists, highlighting its great potential for clinical implementation in breast ultrasound examination.


Asunto(s)
Neoplasias de la Mama , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador , Humanos , Neoplasias de la Mama/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía/métodos , Femenino , Ultrasonografía Mamaria/métodos , Redes Neurales de la Computación
5.
Viruses ; 16(7)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39066328

RESUMEN

Retroviral integration is mediated by intasome nucleoprotein complexes wherein a pair of viral DNA ends are bridged together by a multimer of integrase (IN). Atomic-resolution structures of HIV-1 intasomes provide detailed insights into the mechanism of integration and inhibition by clinical IN inhibitors. However, previously described HIV-1 intasomes are highly heterogeneous and have the tendency to form stacks, which is a limiting factor in determining high-resolution cryo-EM maps. We have assembled HIV-1 intasomes in the presence of excess IN C-terminal domain protein, which was readily incorporated into the intasomes. The purified intasomes were largely homogeneous and exhibited minimal stacking tendencies. The cryo-EM map resolution was further improved to 2.01 Å, which will greatly facilitate structural studies of IN inhibitor action and drug resistance mechanisms. The C-terminal 18 residues of HIV-1 IN, which are critical for virus replication and integration in vitro, have not been well resolved in previous intasome structures, and its function remains unclear. We show that the C-terminal tail participates in intasome assembly, resides within the intasome core, and forms a small alpha helix (residues 271-276). Mutations that disrupt alpha helix integrity impede IN activity in vitro and disrupt HIV-1 infection at the step of viral DNA integration.


Asunto(s)
Microscopía por Crioelectrón , Integrasa de VIH , VIH-1 , Integración Viral , VIH-1/genética , VIH-1/fisiología , VIH-1/enzimología , VIH-1/química , Integrasa de VIH/metabolismo , Integrasa de VIH/química , Integrasa de VIH/genética , Humanos , Dominios Proteicos , Modelos Moleculares , ADN Viral/genética , ADN Viral/metabolismo
6.
Phys Med Biol ; 69(16)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39079547

RESUMEN

Objective.A bone-inclusive ASTM phantom is proposed to improve the assessment of radiofrequency electromagnetic field (RF-EMF) power deposition near orthopedic device under 1.5 T and 3 T magnetic resonance imaging (MRI).Approach.A phantom is created by introducing a cylindrical bone structure inside the American Society for Testing and Materials (ASTM) phantom. Four orthopaedic implant families-rod, nailing system, plate system, and hip replacement-are used in the study. RF-EMF power deposition (in terms of peak averaged specific absorption rate over 1 gram) near these implants are evaluated by placing these implants inside the standard ASTM phantom, the developed bone-inclusive ASTM phantom, and two anatomically representative human body phantoms, known as Duke and Ella. Numerical simulations are performed to calculate the RF-EMF power deposition near various orthopaedic devices within these phantoms.Main Results.For devices implanted inside or near bone tissue, the evaluation of RF-EMF power deposition using the developed bone-inclusive ASTM phantom shows better correlations to the human body phantoms than the ASTM phantom. This improvement is attributed to the portion of the devices implanted within the bone tissue.Significance.The bone-inclusive ASTM phantom has the different tissue of interests surrounding the implants compared to the ASTM phantom. This variation can lead to the different resonance frequency under RF-EMF exposure. This leads to better correlation of RF-EMF power deposition near orthopaedic implants inside human body, making the bone-inclusive ASTM phantom more suitable for evaluating RF-EMF power deposition than ASTM phantom in MRI scans.


Asunto(s)
Huesos , Campos Electromagnéticos , Imagen por Resonancia Magnética , Fantasmas de Imagen , Ondas de Radio , Imagen por Resonancia Magnética/instrumentación , Humanos , Huesos/diagnóstico por imagen , Prótesis e Implantes , Ortopedia
7.
J Biol Chem ; 300(7): 107468, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876301

RESUMEN

The nucleosome remodeling and deacetylase (NuRD) complex plays a pivotal role in chromatin regulation and transcriptional repression. In mice, methyl-CpG binding domain 3 isoform C (MBD3C) interacts specifically with the histone H3 binding protein WD repeat-containing protein 5 (WDR5) and forms the WDR5-MBD3C/Norde complex. Despite the functional significance of this interaction on embryonic stem cell gene regulation, the molecular mechanism underlying MBD3C recognition by WDR5 remains elusive. Here, we determined the crystal structure of WDR5 in complex with the peptide (residues 40-51) derived from the MBD3C protein at a resolution of 1.9 Å. Structural analysis revealed that MBD3C utilizes a unique binding mode to interact with WDR5, wherein MBD3C Arg43 and Phe47 are involved in recognizing the WDR5-interacting (WIN) site and Tyr191-related B site on the small surface of WDR5, respectively. Notably, the binding induces a ∼91° rotation of WDR5 Tyr191, generating the hydrophobic B site. Furthermore, mutation experiments combined with isothermal titration calorimetry (ITC) assays confirmed the importance of both Arg43 and Phe47 in mediating WDR5 binding affinity. By determining structures of various peptides bound to WDR5, we demonstrated that the WDR5 WIN site and B site can be concurrently recognized by WIN motif peptides containing ''Arg-Cies/Ser-Arg-Val-Phe'' consensus sequence. Overall, this study reveals the structural basis for the formation of the WDR5-MBD3C subcomplex and provides new insights into the recognition mode of WDR5 for the WIN motif. Moreover, these findings shed light on structural-based designs of WDR5-targeted anti-cancer small molecule inhibitors or peptide-mimic drugs.


Asunto(s)
Unión Proteica , Ratones , Animales , Cristalografía por Rayos X , Secuencias de Aminoácidos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Humanos , Sitios de Unión
8.
Cancer Control ; 31: 10732748241251580, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38712609

RESUMEN

BACKGROUND: Immune-based therapies are commonly employed to combat hepatocellular carcinoma (HCC). However, the presence of immune-regulating elements, especially regulatory T cells (Tregs), can dramatically impact the treatment efficacy. A deeper examination of the immune-regulation mechanisms linked to these inhibitory factors and their impact on HCC patient outcomes is warranted. METHODS: We employed multicolor fluorescence immunohistochemistry (mIHC) to stain Foxp3, cytokeratin, and nuclei on an HCC tissue microarray (TMA). Leveraging liver cancer transcriptome data from TCGA, we built a prognostic model focused on Treg-associated gene sets and represented it with a nomogram. We then sourced liver cancer single-cell RNA sequencing data (GSE140228) from the GEO database, selectively focusing on Treg subsets, and conducted further analyses, including cell-to-cell communication and pseudo-time trajectory examination. RESULTS: Our mIHC results revealed a more substantial presence of Foxp3+Tregs in HCC samples than in adjacent normal tissue samples (P < .001). An increased presence of Foxp3+Tregs in HCC samples correlated with unfavorable patient outcomes (HR = 1.722, 95% CI:1.023-2.899, P = .041). The multi-factorial prognosis model we built from TCGA liver cancer data highlighted Tregs as a standalone risk determinant for predicting outcomes (HR = 3.84, 95% CI:2.52-5.83, P < .001). Re-analyzing the scRNA-seq dataset (GSE140228) showcased distinctive gene expression patterns in Tregs from varying tissues. Interactions between Tregs and other CD4+T cell types were predominantly governed by the CXCL13/CXCR3 signaling pathway. Communication pathways between Tregs and macrophages primarily involved MIF-CD74/CXCR4, LGALS9/CD45, and PTPRC/MRC1. Additionally, macrophages could influence Tregs via HLA-class II and CD4 interactions. CONCLUSION: An elevated presence of Tregs in HCC samples correlated with negative patient outcomes. Elucidating the interplay between Tregs and other immune cells in HCC could provide insights into the modulatory role of Tregs within HCC tissues.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Linfocitos T Reguladores , Humanos , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Linfocitos T Reguladores/inmunología , Pronóstico , Factores de Transcripción Forkhead/metabolismo , Masculino , Femenino
9.
Exp Cell Res ; 439(1): 114074, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38710403

RESUMEN

Ferroptosis inhibits tumor progression in pancreatic cancer cells, while PITX2 is known to function as a pro-oncogenic factor in various tumor types, protecting them from ferroptosis and thereby promoting tumor progression. In this study, we sought to investigate the regulatory role of PITX2 in tumor cell ferroptosis within the context of pancreatic cancer. We conducted PITX2 knockdown experiments using lentiviral infection in two pancreatic cancer cell lines, namely PANC-1 and BxPC-3. We assessed protein expression through immunoblotting and mRNA expression through RT-PCR. To confirm PITX2 as a transcription factor for GPX4, we employed Chromatin Immunoprecipitation (ChIP) and Dual-luciferase assays. Furthermore, we used flow cytometry to measure reactive oxygen species (ROS), lipid peroxidation, and apoptosis and employed confocal microscopy to assess mitochondrial membrane potential. Additionally, electron microscopy was used to observe mitochondrial structural changes and evaluate PITX2's regulation of ferroptosis in pancreatic cancer cells. Our findings demonstrated that PITX2, functioning as a transcription factor for GPX4, promoted GPX4 expression, thereby exerting an inhibitory effect on ferroptosis in pancreatic cancer cells and consequently promoting tumor progression. Moreover, PITX2 enhanced the invasive and migratory capabilities of pancreatic cancer cells by activating the WNT signaling pathway. Knockdown of PITX2 increased ferroptosis and inhibited the proliferation of PANC-1 and BxPC-3 cells. Notably, the inhibitory effect on ferroptosis resulting from PITX2 overexpression in these cells could be countered using RSL3, an inhibitor of GPX4. Overall, our study established PITX2 as a transcriptional regulator of GPX4 that could promote tumor progression in pancreatic cancer by reducing ferroptosis. These findings suggest that PITX2 may serve as a potential therapeutic target for combating ferroptosis in pancreatic cancer.


Asunto(s)
Ferroptosis , Regulación Neoplásica de la Expresión Génica , Proteína del Homeodomínio PITX2 , Proteínas de Homeodominio , Neoplasias Pancreáticas , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Especies Reactivas de Oxígeno , Factores de Transcripción , Animales , Humanos , Ratones , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Ferroptosis/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Peroxidación de Lípido , Potencial de la Membrana Mitocondrial/genética , Ratones Desnudos , Mitocondrias/metabolismo , Mitocondrias/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Vía de Señalización Wnt/genética
10.
bioRxiv ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38746397

RESUMEN

The transcriptional coactivators EP300 and CREBBP are critical regulators of gene expression that share high sequence identity but exhibit non-redundant functions in basal and pathological contexts. Here, we report the development of a bifunctional small molecule, MC-1, capable of selectively degrading EP300 over CREBBP. Using a potent aminopyridine-based inhibitor of the EP300/CREBBP catalytic domain in combination with a VHL ligand, we demonstrate that MC-1 preferentially degrades EP300 in a proteasome-dependent manner. Mechanistic studies reveal that selective degradation cannot be predicted solely by target engagement or ternary complex formation, suggesting additional factors govern paralogue-specific degradation. MC-1 inhibits cell proliferation in a subset of cancer cell lines and provides a new tool to investigate the non-catalytic functions of EP300 and CREBBP. Our findings expand the repertoire of EP300/CREBBP-targeting chemical probes and offer insights into the determinants of selective degradation of highly homologous proteins.

11.
Inorg Chem ; 63(17): 7937-7945, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38629190

RESUMEN

The urea-assisted water splitting not only enables a reduction in energy consumption during hydrogen production but also addresses the issue of environmental pollution caused by urea. Doping heterogeneous atoms in Ni-based electrocatalysts is considered an efficient means for regulating the electronic structure of Ni sites in catalytic processes. However, the current methodologies for synthesizing heteroatom-doped Ni-based electrocatalysts exhibit certain limitations, including intricate experimental procedures, prolonged reaction durations, and low product yield. Herein, Fe-doped NiO electrocatalysts were successfully synthesized using a rapid and facile solution combustion method, enabling the synthesis of 1.1107 g within a mere 5 min. The incorporation of iron atoms facilitates the modulation of the electronic environment around Ni atoms, generating a substantial decrease in the Gibbs free energy of intermediate species for the Fe-NiO catalyst. This modification promotes efficient cleavage of C-N bonds and consequently enhances the catalytic performance of UOR. Benefiting from the tunability of the electronic environment around the active sites and its efficient electron transfer, Fe-NiO electrocatalysts only needs 1.334 V to achieve 50 mA cm-2 during UOR. Moreover, Fe-NiO catalysts were integrated into a dual electrode urea electrolytic system, requiring only 1.43 V of cell voltage at 10 mA cm-2.

12.
J Mol Biol ; 436(10): 168557, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38582148

RESUMEN

Retroviral DNA integration is mediated by nucleoprotein complexes (intasomes) in which a pair of viral DNA ends are bridged by a multimer of integrase (IN). Most of the high-resolution structures of HIV-1 intasomes are based on an HIV-1 IN with an Sso7d protein domain fused to the N-terminus. Sso7d-IN aggregates much less than wild-type IN and has been critical for structural studies of HIV-1 intasomes. Unexpectedly, these structures revealed that the common core architecture that mediates catalysis could be assembled in various ways, giving rise to both tetrameric and dodecameric intasomes, together with other less well-characterized species. This differs from related retroviruses that assemble unique multimeric intasomes, although the number of protomers in the intasome varies between viruses. The question of whether the additional Sso7d domain contributes to the heterogeneity of HIV-1 intasomes is therefore raised. We have addressed this by biochemical and structural studies of intasomes assembled with wild-type HIV-1 IN. Negative stain and cryo-EM reveal a similar range of multimeric intasome species as with Sso7d-IN with the same common core architecture. Stacks of intasomes resulting from domain swapping are also seen with both wild-type and Sso7d-IN intasomes. The propensity to assemble multimeric intasome species is, therefore, an intrinsic property of HIV-1 IN and is not conferred by the presence of the Sso7d domain. The recently solved intasome structures of different retroviral species, which have been reported to be tetrameric, octameric, dodecameric, and hexadecameric, highlight how a common intasome core architecture can be assembled in different ways for catalysis.


Asunto(s)
Integrasa de VIH , VIH-1 , Integración Viral , Humanos , ADN Viral/química , Integrasa de VIH/química , VIH-1/enzimología , Modelos Moleculares , Nucleoproteínas/química , Multimerización de Proteína
13.
Biosci Trends ; 18(2): 165-175, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38583982

RESUMEN

Hearing loss is the third most prevalent physical condition affecting communication, well-being, and healthcare costs. Sensorineural hearing loss often occurs first in the high-frequency region (basal turn), then towards the low-frequency region (apical turn). However, the mechanism is still unclear. Supporting cells play a critical role in the maintenance of normal cochlear function. The function and supporting capacity of these cells may be different from different frequency regions. Hensen's cells are one of the unique supporting cell types characterized by lipid droplets (LDs) in the cytoplasm. Here, we investigated the morphological and gene expression differences of Hensen's cells along the cochlear axis. We observed a gradient change in the morphological characteristics of Hensen's cells along the cochlear tonotopic axis, with larger and more abundant LDs observed in apical Hensen's cells. Smart-seq2 RNA-seq revealed differentially expressed genes (DEGs) between apical and basal Hensen's cells that clustered in several pathways, including unsaturated fatty acid biosynthesis, cholesterol metabolism, and fatty acid catabolism, which are associated with different energy storage capacities and metabolic potential. These findings suggest potential differences in lipid metabolism and oxidative energy supply between apical and basal Hensen's cells, which is consistent with the morphological differences of Hensen's cells. We also found differential expression patterns of candidate genes associated with hereditary hearing loss (HHL), noise-induced hearing loss (NIHL), and age-related hearing loss (ARHL). These findings indicate functional heterogeneity of SCs along the cochlear axis, contribute to our understanding of cochlear physiology and provide molecular basis evidence for future studies of hearing loss.


Asunto(s)
Análisis de Secuencia de ARN , Animales , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva Sensorineural/patología , Metabolismo de los Lípidos/genética , Cóclea/patología , Cóclea/metabolismo , Gotas Lipídicas/metabolismo , Humanos
14.
Surg Endosc ; 38(5): 2622-2631, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38499780

RESUMEN

BACKGROUND: Postoperative pancreatic fistula (POPF) is the most prevalent complications following minimally invasive pancreaticoduodenectomy (MIPD). Only one model related to MIPD exists, and previous POPF scoring prediction methods are based on open pancreaticoduodenectomy patients. Our objectives are to determine the variables that may increase the probability of pancreatic fistula following MIPD and to develop and validate a POPF predictive risk model. METHODS: Data from 432 patients who underwent MIPD between July 2015 and May 2022 were retrospectively collected. A nomogram prediction model was created using multivariate logistic regression analysis to evaluate independent factors for POPF in patients undergoing MIPD in the modeling cohort. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) and the calibration curve were used to verify the nomogram prediction model internally and externally within the modeling cohort and the verification cohort. RESULTS: Multivariate logistic regression analysis showed that body mass index (BMI), albumin, triglycerides, pancreatic duct diameter, pathological diagnosis and intraoperative bleeding were independent variables for POPF. On the basis of this information, a model for the prediction of risks associated with POPF was developed. In accordance with the ROC analysis, the modeling cohort's AUC was 0.819 (95% CI 0.747-0.891), the internal validation cohort's AUC was 0.830 (95% CI 0.747-0.912), and the external validation cohort's AUC was 0.793 (95% CI 0.671-0.915). Based on the calibration curve, the estimated values of POPF have a high degree of concordance with the actual values that were measured. CONCLUSIONS: This model for predicting the probability of pancreatic fistula following MIPD has strong predictive capacity and can provide a trustworthy predictive method for the early screening of high-risk patients with pancreatic fistula after MIPD and timely clinical intervention.


Asunto(s)
Nomogramas , Fístula Pancreática , Pancreaticoduodenectomía , Complicaciones Posoperatorias , Humanos , Fístula Pancreática/etiología , Fístula Pancreática/epidemiología , Pancreaticoduodenectomía/efectos adversos , Femenino , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/diagnóstico , Anciano , Factores de Riesgo , Curva ROC , Adulto , Medición de Riesgo/métodos
15.
Cancer Lett ; 588: 216769, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38438098

RESUMEN

Cancer-associated fibroblasts (CAFs) play an important role in a variety of cancers. However, the role of tumor stroma in nonfunctional pancreatic neuroendocrine tumors (NF-PanNETs) is often neglected. Profiling the heterogeneity of CAFs can reveal the causes of malignant phenotypes in NF-PanNETs. Here, we found that patients with high stromal proportion had poor prognosis, especially for that with infiltrating stroma (stroma and tumor cells that presented an infiltrative growth pattern and no regular boundary). In addition, myofibroblastic CAFs (myCAFs), characterized by FAP+ and α-SMAhigh, were spatially closer to tumor cells and promoted the EMT and tumor growth. Intriguingly, only tumor cells which were spatially closer to myCAFs underwent EMT. We further elucidated that myCAFs stimulate TGF-ß expression in nearby tumor cells. Then, TGF-ß promoted the EMT in adjacent tumor cells and promoted the expression of myCAFs marker genes in tumor cells, resulting in distant metastasis. Our results indicate that myCAFs cause spatial heterogeneity of EMT, which accounts for liver metastasis of NF-PanNETs. The findings of this study might provide possible targets for the prevention of liver metastasis.


Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias Hepáticas , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Línea Celular Tumoral , Tumores Neuroendocrinos/patología , Fibroblastos Asociados al Cáncer/metabolismo , Neoplasias Pancreáticas/patología , Fenotipo , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias Hepáticas/patología , Microambiente Tumoral
16.
Microb Biotechnol ; 17(2): e14415, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38381074

RESUMEN

Green manufacture of steroid precursors from diosgenin by microbial replacing multistep chemical synthesis has been elusive. It is currently limited by the lack of strain and degradation mechanisms. Here, we demonstrated the feasibility of this process using a novel strain Mycolicibacterium sp. HK-90 with efficiency in diosgenin degradation. Diosgenin degradation by strain HK-90 involves the selective removal of 5,6-spiroketal structure, followed by the oxygenolytic cleavage of steroid nuclei. Bioinformatic analyses revealed the presence of two complete steroid catabolic gene clusters, SCG-1 and SCG-2, in the genome of strain HK-90. SCG-1 cluster was found to be involved in classic phytosterols or cholesterol catabolic pathway through the deletion of key kstD1 gene, which promoted the mutant m-∆kstD1 converting phytosterols to intermediate 9α-hydroxyandrostenedione (9-OHAD). Most impressively, global transcriptomics and characterization of key genes suggested SCG-2 as a potential gene cluster encoding diosgenin degradation. The gene inactivation of kstD2 in SCG-2 resulted in the conversion of diosgenin to 9-OHAD and 9,16-dihydroxy-pregn-4-ene-3,20-dione (9,16-(OH)2 -PG) in mutant m-ΔkstD2. Moreover, the engineered strain mHust-ΔkstD1,2,3 with a triple deletion of kstDs was constructed, which can stably accumulate 9-OHAD by metabolizing phytosterols, and accumulate 9-OHAD and 9,16-(OH)2 -PG from diosgenin. Diosgenin catabolism in strain mHust-ΔkstD1,2,3 was revealed as a progression through diosgenone, 9,16-(OH)2 -PG, and 9-OHAD to 9α-hydroxytestosterone (9-OHTS). So far, this work is the first report on genetically engineered strain metabolizing diosgenin to produce 21-carbon and 19-carbon steroids. This study presents a promising biosynthetic platform for the green production of steroid precursors, and provide insights into the complex biochemical mechanism of diosgenin catabolism.


Asunto(s)
Diosgenina , Fitosteroles , Esteroides , Carbono , Comercio
17.
Ann Surg ; 279(4): 605-612, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37965767

RESUMEN

OBJECTIVE: This study aimed to estimate whether the potential short-term advantages of laparoscopic pancreaticoduodenectomy (LPD) could allow patients to recover in a more timely manner and achieve better long-term survival than with open pancreaticoduodenectomy (OPD) in patients with pancreatic or periampullary tumors. BACKGROUND: LPD has been demonstrated to be feasible and may have several potential advantages over OPD in terms of shorter hospital stay and accelerated recovery than OPD. METHODS: This noninferiority, open-label, randomized clinical trial was conducted in 14 centers in China. The initial trial included 656 eligible patients with pancreatic or periampullary tumors enrolled from May 18, 2018, to December 19, 2019. The participants were randomized preoperatively in a 1:1 ratio to undergo either LPD (n=328) or OPD (n=328). The 3-year overall survival (OS), quality of life, which was assessed using the 3-level version of the European Quality of Life-5 Dimensions, depression, and other outcomes were evaluated. RESULTS: Data from 656 patients [328 men (69.9%); mean (SD) age: 56.2 (10.7) years] who underwent pancreaticoduodenectomy were analyzed. For malignancies, the 3-year OS rates were 59.1% and 54.3% in the LPD and OPD groups, respectively ( P =0.33, hazard ratio: 1.16, 95% CI: 0.86-1.56). The 3-year OS rates for others were 81.3% and 85.6% in the LPD and OPD groups, respectively ( P =0.40, hazard ratio: 0.70, 95% CI: 0.30-1.63). No significant differences were observed in quality of life, depression and other outcomes between the 2 groups. CONCLUSION: In patients with pancreatic or periampullary tumors, LPD performed by experienced surgeons resulted in a similar 3-year OS compared with OPD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03138213.


Asunto(s)
Laparoscopía , Neoplasias Pancreáticas , Masculino , Humanos , Persona de Mediana Edad , Pancreaticoduodenectomía/métodos , Estudios de Seguimiento , Calidad de Vida , Laparoscopía/métodos , Tiempo de Internación , Estudios Retrospectivos , Complicaciones Posoperatorias/cirugía
18.
J Environ Manage ; 351: 119937, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38159304

RESUMEN

Petroleum hydrocarbon (PHC) degrading bacteria have been frequently discovered. However, in practical application, a single species of PHC degrading bacterium with weak competitiveness may face environmental pressure and competitive exclusion due to the interspecific competition between petroleum-degrading bacteria as well as indigenous microbiota in soil, leading to a reduced efficacy or even malfunction. In this study, the diesel degradation ability and environmental robustness of an endophytic strain Pseudomonas aeruginosa WS02, were investigated. The results show that the cell membrane surface of WS02 was highly hydrophobic, and the strain secreted glycolipid surfactants. Genetic analysis results revealed that WS02 contained multiple metabolic systems and PHC degradation-related genes, indicating that this strain theoretically possesses the capability of oxidizing both alkanes and aromatic hydrocarbons. Gene annotation also showed many targets which coded for heavy metal resistant and metal transporter proteins. The gene annotation-based inference was confirmed by the experimental results: GC-MS analysis revealed that short chain PHCs (C10-C14) were completely degraded, and the degradation of PHCs ranging from C15-C22 were above 90% after 14 d in diesel-exposed culture; Heavy metal (Mn2+, Pb2+ and Zn2+) exposure was found to affect the growth of WS02 to some extent, but not its ability to degrade diesel, and the degradation efficiency was still maintained at 39-59%. WS02 also showed a environmental robustness along with PHC-degradation performance in the co-culture system with other bacterial strains as well as in the co-cultured system with the indigenous microbiota in soil fluid extracted from a PHC-contaminated site. It can be concluded that the broad-spectrum diesel degradation efficacy and great environmental robustness give P. aeruginosa WS02 great potential for application in the remediation of PHC-contaminated soil.


Asunto(s)
Metales Pesados , Petróleo , Contaminantes del Suelo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Biodegradación Ambiental , Contaminantes del Suelo/análisis , Petróleo/análisis , Hidrocarburos/metabolismo , Bacterias/metabolismo , Suelo/química , Metales Pesados/análisis , Microbiología del Suelo
19.
Foods ; 12(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37959022

RESUMEN

The structure and assembly properties of ferritin derived from aquatic products remain to be explored. Constructing diverse three-dimensional (3D) protein architectures with the same building blocks has important implications for nutrient delivery, medicine and materials science. Herein, ferritin from Asterias forbesii (AfFer) was prepared, and its crystal structure was resolved at 1.91 Å for the first time. Notably, different from the crystal structure of other reported ferritin, AfFer exhibited a BCT lattice arrangement in its crystals. Bioinspired by the crystal structure of AfFer, we described an effective approach for manufacturing 3D porous, crystalline nanoarchitectures by redesigning the shared protein interface involved in different 3D protein arrays. Based on this strategy, two 3D superlattices of body-centered tetragonal and simple cubicwere constructed with ferritin molecules as the building blocks. This study provided a potentially generalizable strategy for constructing different 3D protein-based crystalline biomaterials with the same building blocks.

20.
Sensors (Basel) ; 23(21)2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37960672

RESUMEN

Short message services (SMS), microblogging tools, instant message apps, and commercial websites produce numerous short text messages every day. These short text messages are usually guaranteed to reach mass audience with low cost. Spammers take advantage of short texts by sending bulk malicious or unwanted messages. Short texts are difficult to classify because of their shortness, sparsity, rapidness, and informal writing. The effectiveness of the hidden Markov model (HMM) for short text classification has been illustrated in our previous study. However, the HMM has limited capability to handle new words, which are mostly generated by informal writing. In this paper, a hybrid model is proposed to address the informal writing issue by weighting new words for fast short text filtering with high accuracy. The hybrid model consists of an artificial neural network (ANN) and an HMM, which are used for new word weighting and spam filtering, respectively. The weight of a new word is calculated based on the weights of its neighbor, along with the spam and ham (i.e., not spam) probabilities of short text message predicted by the ANN. Performance evaluations on benchmark datasets, including the SMS message data maintained by University of California, Irvine; the movie reviews, and the customer reviews are conducted. The hybrid model operates at a significantly higher speed than deep learning models. The experiment results show that the proposed hybrid model outperforms other prominent machine learning algorithms, achieving a good balance between filtering throughput and accuracy.

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