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1.
Nature ; 630(8016): 484-492, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811729

RESUMEN

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Asunto(s)
Bacterias , Bacteriófagos , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Bacterias/virología , Bacterias/genética , Bacterias/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Chryseobacterium/genética , Chryseobacterium/inmunología , Chryseobacterium/virología , Proteína 9 Asociada a CRISPR/química , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/inmunología , División del ADN , Sitios Genéticos/genética , Modelos Moleculares , Dominios Proteicos
2.
Mol Cell ; 82(6): 1199-1209.e6, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35219382

RESUMEN

A compact protein with a size of <1,000 amino acids, the CRISPR-associated protein CasX is a fundamentally distinct RNA-guided nuclease when compared to Cas9 and Cas12a. Although it can induce RNA-guided genome editing in mammalian cells, the activity of CasX is less robust than that of the widely used S. pyogenes Cas9. Here, we show that structural features of two CasX homologs and their guide RNAs affect the R-loop complex assembly and DNA cleavage activity. Cryo-EM-based structural engineering of either the CasX protein or the guide RNA produced two new CasX genome editors (DpbCasX-R3-v2 and PlmCasX-R1-v2) with significantly improved DNA manipulation efficacy. These results advance both the mechanistic understanding of CasX and its application as a genome-editing tool.


Asunto(s)
Edición Génica , ARN Guía de Kinetoplastida , Animales , Sistemas CRISPR-Cas/genética , Endonucleasas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Mamíferos/metabolismo , ARN/genética , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo
3.
Proc Natl Acad Sci U S A ; 121(22): e2402764121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38771879

RESUMEN

Staphylococcus aureus (S. aureus) can evade antibiotics and host immune defenses by persisting within infected cells. Here, we demonstrate that in infected host cells, S. aureus type VII secretion system (T7SS) extracellular protein B (EsxB) interacts with the stimulator of interferon genes (STING) protein and suppresses the inflammatory defense mechanism of macrophages during early infection. The binding of EsxB with STING disrupts the K48-linked ubiquitination of EsxB at lysine 33, thereby preventing EsxB degradation. Furthermore, EsxB-STING binding appears to interrupt the interaction of 2 vital regulatory proteins with STING: aspartate-histidine-histidine-cysteine domain-containing protein 3 (DHHC3) and TNF receptor-associated factor 6. This persistent dual suppression of STING interactions deregulates intracellular proinflammatory pathways in macrophages, inhibiting STING's palmitoylation at cysteine 91 and its K63-linked ubiquitination at lysine 83. These findings uncover an immune-evasion mechanism by S. aureus T7SS during intracellular macrophage infection, which has implications for developing effective immunomodulators to combat S. aureus infections.


Asunto(s)
Proteínas Bacterianas , Macrófagos , Proteínas de la Membrana , Infecciones Estafilocócicas , Staphylococcus aureus , Sistemas de Secreción Tipo VII , Ubiquitinación , Staphylococcus aureus/inmunología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/inmunología , Humanos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/microbiología , Animales , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/metabolismo , Sistemas de Secreción Tipo VII/metabolismo , Sistemas de Secreción Tipo VII/inmunología , Sistemas de Secreción Tipo VII/genética , Ratones , Evasión Inmune , Interacciones Huésped-Patógeno/inmunología
4.
Proc Natl Acad Sci U S A ; 121(11): e2312136121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38446848

RESUMEN

Anxiety is a remarkably common condition among patients with pharyngitis, but the relationship between these disorders has received little research attention, and the underlying neural mechanisms remain unknown. Here, we show that the densely innervated pharynx transmits signals induced by pharyngeal inflammation to glossopharyngeal and vagal sensory neurons of the nodose/jugular/petrosal (NJP) superganglia in mice. Specifically, the NJP superganglia project to norepinephrinergic neurons in the nucleus of the solitary tract (NTSNE). These NTSNE neurons project to the ventral bed nucleus of the stria terminalis (vBNST) that induces anxiety-like behaviors in a murine model of pharyngeal inflammation. Inhibiting this pharynx→NJP→NTSNE→vBNST circuit can alleviate anxiety-like behaviors associated with pharyngeal inflammation. This study thus defines a pharynx-to-brain axis that mechanistically links pharyngeal inflammation and emotional response.


Asunto(s)
Faringitis , Faringe , Humanos , Animales , Ratones , Ansiedad , Encéfalo , Células Receptoras Sensoriales , Inflamación
5.
Int J Cancer ; 155(8): 1400-1408, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38822730

RESUMEN

Nasopharyngeal carcinoma (NPC) risk prediction models based on Epstein-Barr virus (EBV)-antibody testing have shown potential for screening of NPC; however, the long-term stability is unclear. Here, we investigated the kinetics of two EBV-antibody NPC risk scores within the Taiwan NPC Multiplex Family Study. Among 545 participants with multiple blood samples, we evaluated the stability of a 2-marker enzyme-linked immunosorbent assay score and 13-marker multiplex serology score using the intra-class correlation coefficient (ICC) by fitting a linear mixed model that accounted for the clustering effect of multiple measurements per subject and age. We also estimated the clustering of positive tests using Fleiss's kappa statistic. Over an average 20-year follow-up, the 2-marker score showed high stability over time, whereas the 13-marker score was more variable (p < .05). Case-control status is associated with the kinetics of the antibody response, with higher ICCs among cases. Positive tests were more likely to cluster within the same individual for the 2-marker score than the 13-marker score (p < .05). The 2-marker score had an increase in specificity from ~90% for single measurement to ~96% with repeat testing. The 13-marker score had a specificity of ~73% for a single measurement that increased to ~92% with repeat testing. Among individuals who developed NPC, none experienced score reversion. Our findings suggest that repeated testing could improve the specificity of NPC screening in high-risk NPC multiplex families. Further studies are required to determine the impact on sensitivity, establish optimal screening intervals, and generalize these findings to general population settings in high-risk regions.


Asunto(s)
Anticuerpos Antivirales , Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Taiwán/epidemiología , Herpesvirus Humano 4/inmunología , Anticuerpos Antivirales/sangre , Masculino , Femenino , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/epidemiología , Infecciones por Virus de Epstein-Barr/virología , Adulto , Persona de Mediana Edad , Neoplasias Nasofaríngeas/virología , Neoplasias Nasofaríngeas/inmunología , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/sangre , Neoplasias Nasofaríngeas/epidemiología , Carcinoma Nasofaríngeo/virología , Carcinoma Nasofaríngeo/inmunología , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/sangre , Carcinoma Nasofaríngeo/epidemiología , Cinética , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Adulto Joven , Factores de Riesgo , Anciano
6.
Kidney Int ; 105(3): 562-581, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38142040

RESUMEN

The parathyroid gland is one of the main organs that regulate calcium and phosphorus metabolism. It is mainly composed of chief cells and oxyphil cells. Oxyphil cell counts are low in the parathyroid glands of healthy adults but are dramatically increased in patients with uremia and secondary hyperparathyroidism (SHPT). Increased oxyphil cell counts are related to drug treatment resistance, but the origin of oxyphil cells and the mechanism of proliferation remain unknown. Herein, three types of parathyroid nodules (chief cell nodules, oxyphil cell nodules and mixed nodules, respectively) excised from parathyroid glands of uremic SHPT patients were used for single-cell RNA sequencing (scRNA-seq), other molecular biology studies, and transplantation into nude mice. Through scRNA-seq of parathyroid mixed nodules from three patients with uremic SHPT, we established the first transcriptomic map of the human parathyroid and found a chief-to-oxyphil cell transdifferentiation characterized by gradual mitochondrial enrichment associated with the uremic milieu. Notably, the mitochondrial enrichment and cellular proliferation of chief cell and oxyphil cell nodules decreased significantly after leaving the uremic milieu via transplantation into nude mice. Remarkably, the phenotype of oxyphil cell nodules improved significantly in the nude mice as characterized by decreased mitochondrial content and the proportion of oxyphil cells to chief cells. Thus, our study provides a comprehensive single-cell transcriptome atlas of the human parathyroid and elucidates the origin of parathyroid oxyphil cells and their underlying transdifferentiating mechanism. These findings enhance our understanding of parathyroid disease and may open new treatment perspectives for patients with chronic kidney disease.


Asunto(s)
Hiperparatiroidismo Secundario , Glándulas Paratiroides , Adulto , Animales , Ratones , Humanos , Glándulas Paratiroides/metabolismo , Células Oxífilas , Ratones Desnudos , Transdiferenciación Celular , Hiperparatiroidismo Secundario/genética , Hiperparatiroidismo Secundario/terapia , Análisis de Secuencia de ARN
7.
Anal Chem ; 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39392688

RESUMEN

Ultrasensitive analysis of organic molecules is crucial for various fundamental research and applications. State-of-the-art techniques for this purpose can achieve detection limits of several hundred ppq (parts-per-quadrillion), while a higher sensitivity is pursued constantly. To achieve this goal, we develop femtosecond laser assisted chemical ionization for mass spectrometry. This technique combines the advantages of femtosecond laser ionization and chemical ionization, either of which enables subppt (parts-per-trillion) mass spectrometry analysis of organic molecules. The results demonstrate that the developed ionization technique, when employed in mass spectrometry, can surpass femtosecond laser ionization by more than 3 orders of magnitude in sensitivity, while still maintaining good versatility and the ability to work under ambient conditions. This work paves the way for subppq analysis of organic molecules in gas phase and even in ambient environments, which can open up new research fields for trace substance analysis in atmospheric environment, clinical diagnosis, biomedical studies, etc.

8.
Mol Carcinog ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150155

RESUMEN

Proliferation is a critical characteristic of the progression of gastric cancer (GC). Receptor tyrosine kinase-like orphan receptor 2 (ROR2), the orphan receptor tyrosine kinase-like receptor, exhibits effects on tumor growth due to its abnormal expression in cancer. The goal of our study was to assess the potential regulatory role exerted by the ROR2 on GC cells. Through previous bioinformatics analysis, we discovered an association between ROR2 and the G2/M phase of the GC cell cycle. However, little is known about the link between ROR2 and the G2/M phase cell cycle in GC. Here, the findings of our study indicate that ROR2, after transcribed expression by Twist1, activates the PI3K/AKT/mTOR/S6K signal transduction pathway, thus leading to the acceleration of the G2/M phase and subsequent promotion of cell proliferation in GC. Furthermore, the functional link among ROR2, Twist1, and G2/M phase of cell cycle was also confirmed in mouse xenograft tissues and human tissues. ROR2 expression was correlated with Twist expression and lower survival in vivo. Notably, our suggestion is that focusing on ROR2 as a potential therapeutic approach could show potential for the management of GC.

9.
J Transl Med ; 22(1): 345, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600566

RESUMEN

BACKGROUND: Hearing loss has been shown to be a risk factor for psychiatric disorders. In addition, long-term hearing loss is associated with increased hospitalization and mortality rates; however, the increased risk and duration of effect of hearing loss in combination with other chronic diseases on each psychiatric disorder are still not clearly defined. The purpose of this article is to clarify the risk of hearing loss for each disorder over time. METHODS: This was a retrospective cohort study, and a national health insurance research database in Taiwan was utilized. All (n = 1,949,101) Taiwanese residents who had a medical visit between 2000 and 2015 were included. Patients with hearing loss and a comparative retrospective cohort were analyzed. Every subject was tracked individually from their index date to identify the subjects who later received a diagnosis of a psychiatric disorder. The Kaplan‒Meier method was used to analyze the cumulative incidence of psychiatric disorders. Cox regression analysis was performed to identify the risk of psychiatric disorders. RESULTS: A total of 13,341 (15.42%) and 31,250 (9.03%) patients with and without hearing loss, respectively, were diagnosed with psychiatric disorders (P < 0.001). Multivariate analysis indicated that hearing loss significantly elevated the risk of psychiatric disorders (adjusted HR = 2.587, 95% CI 1.723-3.346, p < 0.001). CONCLUSION: Our findings indicate that patients with hearing loss are more likely to develop psychiatric disorders. Furthermore, the various psychiatric disorders are more likely to occur at different times. Our findings have important clinical implications, including a need for clinicians to implement early intervention for hearing loss and to pay close attention to patients' psychological status. Trial registration TSGHIRB No. E202216036.


Asunto(s)
Pérdida Auditiva , Trastornos Mentales , Humanos , Estudios de Cohortes , Pérdida Auditiva/complicaciones , Pérdida Auditiva/epidemiología , Incidencia , Trastornos Mentales/complicaciones , Trastornos Mentales/epidemiología , Factores de Riesgo , Taiwán/epidemiología
10.
PLoS Pathog ; 18(12): e1011027, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36469533

RESUMEN

Pseudomonas aeruginosa, a major inhabitant of numerous environmental reservoirs, is a momentous opportunistic human pathogen associated with severe infections even death in the patients suffering from immune deficiencies or metabolic diseases. Type III secretion system (T3SS) employed by P. aeruginosa to inject effector proteins into host cells is one of the pivotal virulence factors pertaining to acute infections caused by this pathogen. Previous studies showed that P. aeruginosa T3SS is regulated by various environmental cues such as calcium concentration and the host signal spermidine. However, how T3SS is regulated and expressed particularly under the ever-changing environmental conditions remains largely elusive. In this study, we reported that a tRNA modification enzyme PA3980, designated as MiaB, positively regulated T3SS gene expression in P. aeruginosa and was essential for the induced cytotoxicity of human lung epithelial cells. Further genetic assays revealed that MiaB promoted T3SS gene expression by repressing the LadS-Gac/Rsm signaling pathway and through the T3SS master regulator ExsA. Interestingly, ladS, gacA, rsmY and rsmZ in the LadS-Gac/Rsm signaling pathway seemed potential targets under the independent regulation of MiaB. Moreover, expression of MiaB was found to be induced by the cAMP-dependent global regulator Vfr as well as the spermidine transporter-dependent signaling pathway and thereafter functioned to mediate their regulation on the T3SS gene expression. Together, these results revealed a novel regulatory mechanism for MiaB, with which it integrates different environmental cues to modulate T3SS gene expression in this important bacterial pathogen.


Asunto(s)
Pseudomonas aeruginosa , Sistemas de Secreción Tipo III , Humanos , Sistemas de Secreción Tipo III/genética , Sistemas de Secreción Tipo III/metabolismo , Pseudomonas aeruginosa/metabolismo , Regulación Bacteriana de la Expresión Génica , Señales (Psicología) , Espermidina/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ARN de Transferencia/metabolismo
11.
Ann Surg Oncol ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154160

RESUMEN

BACKGROUND: Human papillomavirus (HPV) is a crucial prognostic factor in oropharyngeal cancer (OPC). p16 is a surrogate marker for diagnosing HPV+ OPC, however it is not direct evidence of HPV existence. OBJECTIVE: The purpose of our study was to evaluate an HPV DNA test-Cobas HPV assay-in diagnosing HPV+ OPC through neck lymph node aspiration. METHODS: Patients with suspected neck mass who received fine needle aspiration (FNA) or core needle biopsy (CNB) at the National Taiwan University Hospital between January 2018 and December 2022 were reviewed. Besides routine cytology and pathology study, needle rinse fluid was collected for the Cobas HPV assay to detect high-risk HPV. RESULTS: We analyzed 137 patients with suspected lymph nodes, 32 (23.4%) of whom were HPV+ OPC patients and 105 (76.6%) of whom had non-HPV-related disease. FNA was performed in 31 patients and CNB was performed in 106 patients, according to the size and necrosis status of the lymph nodes. For diagnosing HPV+ OPC, CNB combined with p16 immunohistochemistry staining showed sensitivity of 93.3%, specificity of 97.8%, positive predictive value (PPV) of 87.5%, negative predictive value (NPV) of 98.9%, and accuracy of 97.2%. On the other hand, for the needle rinse Roche Cobas HPV assay, the test showed sensitivity of 96.9%, specificity of 100%, PPV of 100%, NPV of 99.1%, and accuracy of 99.3%. Compared with p16 IHC staining, the Cobas HPV test showed better PPV with statistical significance (p = 0.04). CONCLUSION: The Cobas HPV assay is a US FDA-approved, highly automated, and readily used technique to directly detect the presence of high-risk HPV. We recommend utilizing the Cobas HPV assay in combination with routine cytology or histopathology examination in the work-up of neck lymphadenopathy.

12.
Opt Lett ; 49(4): 862-865, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359201

RESUMEN

A diode-pumped wavelength switchable passively Q-switched 2.3 µm Tm:YVO4 laser was demonstrated in this work. A Cr:ZnS saturable absorber was introduced into the cavity for initiating passive Q-switching. With the increase of the absorbed pump power, the passively Q-switched laser could be switched from the single wavelength of 2366 nm to the dual wavelength of 2290 and 2360 nm. The pulse duration and pulse repetition frequency could be tuned in the ranges of 0.745-1.782 µs and 2.9-43.4 kHz, respectively. The pulse energy and peak power were estimated to be 7.5 µJ and 10 W, respectively, at an absorbed pump power of 12 W.

13.
BMC Cancer ; 24(1): 1320, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39456017

RESUMEN

BACKGROUND: The evidence for adjuvant chemoradiotherapy (CRT) of oral cavity squamous cell carcinoma (OCSCC) with extra-nodal extension (ENE) in National Comprehensive Cancer Network (NCCN) guidelines is derived from patients with head and neck cancer. The guidelines further suggest a radiation dose ranging from 6000 to 6600 cGy. In this nationwide study, we sought to evaluate the prognostic significance of adjuvant therapy and the specific radiation dosage in Taiwanese patients with pure OCSCC and ENE. METHODS: A retrospective analysis of 1577 OCSCC patients with ENE who underwent resection and received adjuvant CRT or radiotherapy (RT) between January 2011 and December 2020 was conducted. RESULTS: Multivariable analysis revealed that adjuvant RT, more than four pathologically positive nodes, and radiation dosage below 6000 cGy were independent risk factors for unfavorable 5-year disease-specific survival (DSS) and overall survival (OS). Comparing patients who received CRT (n = 1453) to those treated with RT (n = 124) before and after propensity score (PS) matching, the 5-year outcomes were as follows: before PS matching, DSS (54% versus 30%, p < 0.0001), OS (42% versus 18%, p < 0.0001); after PS matching (n = 111 in each group), DSS (52% versus 30%, p = 0.0016), OS (38% versus 21%, p = 0.0019). For patients who underwent CRT, the 5-year outcomes for different radiation dose groups (6600 - 7000 cGy, n = 1155 versus 6000 - 6500 cGy, n = 199) were as follows: before PS matching, DSS (52% versus 54%, p = 0.1904), OS (43% versus 46%, p = 0.1610); after PS matching (n = 199 in each group), DSS (55% versus 54%, p = 0.8374), OS (46.5% versus 46.3%, p = 0.7578). CONCLUSIONS: For OCSCC patients with ENE, our study shows CRT improved survivals than RT alone, underscoring the clinical significance of chemotherapy. Patients undergoing CRT with irradiation doses ranging from 6000 to 6500 cGy exhibited comparable survival outcomes to those receiving doses of 6600-7000 cGy. This observation suggests that irradiation doses exceeding the 6600 cGy may not confer the survival advantage in these patients. Further research is needed to confirm our results and explore the optimal irradiation dose for managing these patients.


Asunto(s)
Quimioradioterapia Adyuvante , Neoplasias de la Boca , Humanos , Masculino , Femenino , Neoplasias de la Boca/terapia , Neoplasias de la Boca/radioterapia , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Taiwán/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos , Pronóstico , Anciano , Quimioradioterapia Adyuvante/métodos , Dosificación Radioterapéutica , Adulto , Extensión Extranodal , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad
14.
J Org Chem ; 89(3): 1633-1647, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38235569

RESUMEN

A metal-free and atom-economic route for the synthesis of naphtho[1,2-b]furan-3-ones has been realized via p-TsOH·H2O-catalyzed intramolecular tandem double cyclization of γ-hydroxy acetylenic ketones with alkynes in formic acid. The benzene-linked furanonyl-ynes are the key intermediates obtained by the scission/recombination of C-O double bonds. Further, the structural modifications of the representative product were implemented by reduction, demethylation, substitution, and [5 + 2]-cycloaddition.

15.
Cell ; 138(6): 1236-46, 2009 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-19747717

RESUMEN

The eukaryotic circadian oscillators consist of autoregulatory negative feedback loops. However, little is known about the role of posttranscriptional regulation of RNA in circadian oscillators. In the Neurospora circadian negative feedback loop, FRQ and FRH form the FFC complex that represses frq transcription. Here, we show that FFC also binds frq RNA and interacts with the exosome to regulate frq RNA decay. Consequently, frq RNA is robustly rhythmic as it is more stable when FRQ levels are low. Silencing of RRP44, the catalytic subunit of the exosome, elevates frq RNA levels and impairs clock function. In addition, rrp44 is a clock-controlled gene and a direct target of the WHITE COLLAR complex, and RRP44 controls the circadian expression of some ccgs. Taken together, these results suggest that FFC and the exosome are part of a posttranscriptional negative feedback loop that regulates frq transcript levels and the circadian output pathway.


Asunto(s)
Ritmo Circadiano , Exosomas/metabolismo , Regulación Fúngica de la Expresión Génica , Neurospora/genética , Relojes Biológicos , Proteínas Fúngicas/metabolismo , Neurospora/metabolismo , Procesamiento Postranscripcional del ARN
16.
Phys Chem Chem Phys ; 26(34): 22656-22664, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39158723

RESUMEN

Although Mo2C and earth-abundant 3d transition metals are regarded as potential catalysts to replace noble metal catalysts for effective hydrogen evolution reaction, their large-scale application is still inhibited by their own defects. Here, a facile thermal treatment method for nonprecious metal catalysts is developed to prepare a porous Ni/Mo2C composite catalyst. The loading density of Ni nanoparticles on the Mo2C surface has an important effect on the activity of the catalyst. By optimizing the Ni doping ratio, the Ni-40/Mo2C-17 sample exhibits the lowest onset overpotential and lowest overpotential at 10 mA cm-2 in both acidic and alkaline electrolytes, compared to other reported Ni- and Mo2C-based catalysts. In addition, theoretical calculations have also confirmed the synergistic effect between Ni nanoparticles and Mo2C, which can balance the thermodynamics between H adsorption and desorption of H2. This work provides an avenue for designing high-performance water-splitting catalytic materials using low-cost species, which exhibit excellent HER activity in a wide pH range.

17.
Surg Endosc ; 38(4): 2106-2115, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438672

RESUMEN

BACKGROUND: This study aimed to compare postoperative complications in patients with esophagogastric variceal bleeding (EVB) who underwent laparoscopic splenectomy combined with pericardial devascularization (LSPD) versus transjugular intrahepatic portosystemic shunt (TIPS) procedures. METHODS: A retrospective collection of medical records was conducted from January 2014 to May 2020 at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. The study included patients from the departments of trauma surgery, interventional radiology, and general surgery who were diagnosed with EVB caused by portal hypertension and treated with LSPD or TIPS. Follow-up data were obtained to assess the occurrence of postoperative complications in both groups. RESULTS: A total of 201 patients were included in the study, with 104 cases in the LSPD group and 97 cases in the TIPS group. There was no significant difference in the 1-year and 3-year post-surgery survival rates between the TIPS and LSPD groups (P = 0.669, 0.066). The 3-year survival rate of Child-Pugh B patients in the LSPD group was higher than TIPS group (P = 0.041). The LSPD group also had a significantly higher rate of freedom from rebleeding at 3-year post-surgery compared to the TIPS group (P = 0.038). Stratified analysis showed no statistically significant difference in the rebleeding rate between the two groups. Furthermore, the LSPD group had a higher rate of freedom from overt hepatic encephalopathy at 1-year and 3-year post-surgery compared to the TIPS group (P = 0.007, < 0.001). The LSPD group also had a lower rate of severe complications at 3-year post-surgery compared to the TIPS group (P = 0.020). CONCLUSION: Compared to TIPS, LSPD does not increase the risk of mortality and rebleeding, while demonstrating fewer complications. In patients classified as Child-Pugh A and B, the use of LSPD for treating EVB is both safe and effective.


Asunto(s)
Várices Esofágicas y Gástricas , Laparoscopía , Derivación Portosistémica Intrahepática Transyugular , Humanos , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/cirugía , Derivación Portosistémica Intrahepática Transyugular/efectos adversos , Esplenectomía/efectos adversos , Estudios Retrospectivos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/cirugía , Cirrosis Hepática/cirugía , Laparoscopía/efectos adversos , Pronóstico , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
18.
Mol Ther ; 31(1): 134-153, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36056553

RESUMEN

Glioblastoma (GBM) is the most aggressive primary malignant brain cancer and urgently requires effective treatments. Chimeric antigen receptor T (CAR-T) cell therapy offers a potential treatment method, but it is often hindered by poor infiltration of CAR-T cells in tumors and highly immunosuppressive tumor microenvironment (TME). Here, we armed an oncolytic adenovirus (oAds) with a chemokine CXCL11 to increase the infiltration of CAR-T cells and reprogram the immunosuppressive TME, thus improving its therapeutic efficacy. In both immunodeficient and immunocompetent orthotopic GBM mice models, we showed that B7H3-targeted CAR-T cells alone failed to inhibit GBM growth but, when combined with the intratumoral administration of CXCL11-armed oAd, it achieved a durable antitumor response. Besides, oAd-CXCL11 had a potent antitumor effect and reprogramed the immunosuppressive TME in GL261 GBM models, in which increased infiltration of CD8+ T lymphocytes, natural killer (NK) cells, and M1-polarized macrophages, while decreased proportions of myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs) and M2-polarized macrophages were observed. Furthermore, the antitumor effect of the oAd-CXCL11 was CD8+ T cell dependent. Our findings thus revealed that CXCL11-armed oAd can improve immune-virotherapy and can be a promising adjuvant of CAR-T therapy for GBM.


Asunto(s)
Neoplasias Encefálicas , Quimiocina CXCL11 , Glioblastoma , Inmunoterapia Adoptiva , Viroterapia Oncolítica , Receptores Quiméricos de Antígenos , Animales , Ratones , Adenoviridae/genética , Línea Celular Tumoral , Quimiocina CXCL11/genética , Glioblastoma/terapia , Receptores Quiméricos de Antígenos/genética , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Neoplasias Encefálicas/terapia
19.
J Med Internet Res ; 26: e56022, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231422

RESUMEN

BACKGROUND: Breast cancer is a leading global health concern, necessitating advancements in recurrence prediction and management. The development of an artificial intelligence (AI)-based clinical decision support system (AI-CDSS) using ChatGPT addresses this need with the aim of enhancing both prediction accuracy and user accessibility. OBJECTIVE: This study aims to develop and validate an advanced machine learning model for a web-based AI-CDSS application, leveraging the question-and-answer guidance capabilities of ChatGPT to enhance data preprocessing and model development, thereby improving the prediction of breast cancer recurrence. METHODS: This study focused on developing an advanced machine learning model by leveraging data from the Tri-Service General Hospital breast cancer registry of 3577 patients (2004-2016). As a tertiary medical center, it accepts referrals from four branches-3 branches in the northern region and 1 branch on an offshore island in our country-that manage chronic diseases but refer complex surgical cases, including breast cancer, to the main center, enriching our study population's diversity. Model training used patient data from 2004 to 2012, with subsequent validation using data from 2013 to 2016, ensuring comprehensive assessment and robustness of our predictive models. ChatGPT is integral to preprocessing and model development, aiding in hormone receptor categorization, age binning, and one-hot encoding. Techniques such as the synthetic minority oversampling technique address the imbalance of data sets. Various algorithms, including light gradient-boosting machine, gradient boosting, and extreme gradient boosting, were used, and their performance was evaluated using metrics such as the area under the curve, accuracy, sensitivity, and F1-score. RESULTS: The light gradient-boosting machine model demonstrated superior performance, with an area under the curve of 0.80, followed closely by the gradient boosting and extreme gradient boosting models. The web interface of the AI-CDSS tool was effectively tested in clinical decision-making scenarios, proving its use in personalized treatment planning and patient involvement. CONCLUSIONS: The AI-CDSS tool, enhanced by ChatGPT, marks a significant advancement in breast cancer recurrence prediction, offering a more individualized and accessible approach for clinicians and patients. Although promising, further validation in diverse clinical settings is recommended to confirm its efficacy and expand its use.


Asunto(s)
Inteligencia Artificial , Neoplasias de la Mama , Sistemas de Apoyo a Decisiones Clínicas , Internet , Aprendizaje Automático , Humanos , Femenino , Persona de Mediana Edad , Adulto , Anciano
20.
Am J Otolaryngol ; 45(5): 104420, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39067090

RESUMEN

BACKGROUND: Head and neck surgical simulation training (SST) is an important part in otolaryngology head and neck surgical education. In this study, we provide a live porcine model for SST in recurrent laryngeal nerve (RLN) and facial nerve (FN) dissection for otolaryngology head and neck residents. METHODS: A lecture with surgical manual is provided to illustrate the surgical landmarks of pig, and step-by-step procedures for thyroid and parotid surgery, as well as neck dissection. We used 4-month-old pig weighting 32 kg for the SST. The mentor demonstrated result of RLN injury with continuous nerve monitoring. Participants used monopolar stimulation probe (4 pulse/s, 100 µs, 3-8 mA; Medtronic) to identify and intermittent monitor the RLN and FN during the SST. After the dissection course, we conducted a questionnaire survey to check the effectiveness of this training model. RESULTS: Total 30 participants were recruited, including 16 female and 14 male resident doctors. There were 1, 4 and 25 learners for 3rd year, 4th and 5th years residents, respectively. Before this training course, 53 % (16/30) and 63 % (19/30) had successful experience in finding the RLN and FN, respectively. After the SST, all of our participants had successful identify the RLN and FN (p-value <0.01); all had positive response to stimulation and familiar with the procedure. CONCLUSIONS: The live porcine model is effectiveness in SST for RLN and FN dissection. Live porcine model with real-time RLN and FN monitoring should be provided for otolaryngology head and neck resident training.


Asunto(s)
Nervio Facial , Internado y Residencia , Otolaringología , Nervio Laríngeo Recurrente , Entrenamiento Simulado , Animales , Porcinos , Entrenamiento Simulado/métodos , Otolaringología/educación , Internado y Residencia/métodos , Nervio Facial/cirugía , Femenino , Humanos , Masculino , Nervio Laríngeo Recurrente/cirugía , Disección/educación , Modelos Animales , Competencia Clínica , Traumatismos del Nervio Laríngeo Recurrente/prevención & control , Disección del Cuello/educación
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