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1.
Cell ; 172(3): 578-589.e17, 2018 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-29373830

RESUMEN

KRASG12C was recently identified to be potentially druggable by allele-specific covalent targeting of Cys-12 in vicinity to an inducible allosteric switch II pocket (S-IIP). Success of this approach requires active cycling of KRASG12C between its active-GTP and inactive-GDP conformations as accessibility of the S-IIP is restricted only to the GDP-bound state. This strategy proved feasible for inhibiting mutant KRAS in vitro; however, it is uncertain whether this approach would translate to in vivo. Here, we describe structure-based design and identification of ARS-1620, a covalent compound with high potency and selectivity for KRASG12C. ARS-1620 achieves rapid and sustained in vivo target occupancy to induce tumor regression. We use ARS-1620 to dissect oncogenic KRAS dependency and demonstrate that monolayer culture formats significantly underestimate KRAS dependency in vivo. This study provides in vivo evidence that mutant KRAS can be selectively targeted and reveals ARS-1620 as representing a new generation of KRASG12C-specific inhibitors with promising therapeutic potential.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Experimentales/tratamiento farmacológico , Piperazinas/farmacología , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Quinazolinas/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Femenino , Células HCT116 , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Simulación del Acoplamiento Molecular , Mutación , Piperazinas/química , Piperazinas/uso terapéutico , Unión Proteica , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Quinazolinas/química , Quinazolinas/uso terapéutico
2.
Nature ; 585(7823): 63-67, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32879503

RESUMEN

Rechargeable lithium-ion batteries with high energy density that can be safely charged and discharged at high rates are desirable for electrified transportation and other applications1-3. However, the sub-optimal intercalation potentials of current anodes result in a trade-off between energy density, power and safety. Here we report that disordered rock salt4,5 Li3+xV2O5 can be used as a fast-charging anode that can reversibly cycle two lithium ions at an average voltage of about 0.6 volts versus a Li/Li+ reference electrode. The increased potential compared to graphite6,7 reduces the likelihood of lithium metal plating if proper charging controls are used, alleviating a major safety concern (short-circuiting related to Li dendrite growth). In addition, a lithium-ion battery with a disordered rock salt Li3V2O5 anode yields a cell voltage much higher than does a battery using a commercial fast-charging lithium titanate anode or other intercalation anode candidates (Li3VO4 and LiV0.5Ti0.5S2)8,9. Further, disordered rock salt Li3V2O5 can perform over 1,000 charge-discharge cycles with negligible capacity decay and exhibits exceptional rate capability, delivering over 40 per cent of its capacity in 20 seconds. We attribute the low voltage and high rate capability of disordered rock salt Li3V2O5 to a redistributive lithium intercalation mechanism with low energy barriers revealed via ab initio calculations. This low-potential, high-rate intercalation reaction can be used to identify other metal oxide anodes for fast-charging, long-life lithium-ion batteries.

3.
Mol Cell Proteomics ; 22(2): 100494, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36621768

RESUMEN

AMP-activated protein kinase alpha 2 (AMPKα2) regulates energy metabolism, protein synthesis, and glucolipid metabolism myocardial cells. Ketone bodies produced by fatty acid ß-oxidation, especially ß-hydroxybutyrate, are fatty energy-supplying substances for the heart, brain, and other organs during fasting and long-term exercise. They also regulate metabolic signaling for multiple cellular functions. Lysine ß-hydroxybutyrylation (Kbhb) is a ß-hydroxybutyrate-mediated protein posttranslational modification. Histone Kbhb has been identified in yeast, mouse, and human cells. However, whether AMPK regulates protein Kbhb is yet unclear. Hence, the present study explored the changes in proteomics and Kbhb modification omics in the hearts of AMPKα2 knockout mice using a comprehensive quantitative proteomic analysis. Based on mass spectrometry (LC-MS/MS) analysis, the number of 1181 Kbhb modified sites in 455 proteins were quantified between AMPKα2 knockout mice and wildtype mice; 244 Kbhb sites in 142 proteins decreased or increased after AMPKα2 knockout (fold change >1.5 or <1/1.5, p < 0.05). The regulation of Kbhb sites in 26 key enzymes of fatty acid degradation and tricarboxylic acid cycle was noted in AMPKα2 knockout mouse cardiomyocytes. These findings, for the first time, identified proteomic features and Kbhb modification of cardiomyocytes after AMPKα2 knockout, suggesting that AMPKα2 regulates energy metabolism by modifying protein Kbhb.


Asunto(s)
Ácido 3-Hidroxibutírico , Proteínas Quinasas Activadas por AMP , Miocardio , Animales , Humanos , Ratones , Ácido 3-Hidroxibutírico/química , Ácido 3-Hidroxibutírico/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Cromatografía Liquida , Ratones Endogámicos C57BL , Ratones Noqueados , Miocardio/metabolismo , Proteómica , Espectrometría de Masas en Tándem
4.
Nano Lett ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976365

RESUMEN

Sealing wet porous membranes is a major challenge when fabricating cell encapsulation devices. Herein, we report the development of an Autoclavable Transparent Thermal Cutter (ATTC) for reliably sealing wet nanofibrous membranes. Notably, the ATTC is autoclavable and transparent, thus enabling in situ visualization of the sealing process in a sterile environment and ensuring an appropriate seal. In addition, the ATTC could generate smooth, arbitrary-shaped sealing ends with excellent mechanical properties when sealing PA6, PVDF, and TPU nanofibrous tubes and PP microporous membranes. Importantly, the ATTC could reliably seal wet nanofibrous tubes, which can shoulder a burst pressure up to 313.2 ± 19.3 kPa without bursting at the sealing ends. Furthermore, the ATTC sealing process is highly compatible with the fabrication of cell encapsulation devices, as verified by viability, proliferation, cell escape, and cell function tests. We believe that the ATTC could be used to reliably seal cell encapsulation devices with minimal side effects.

5.
Apoptosis ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38960944

RESUMEN

BACKGROUND: Cetuximab is extensively used in the treatment of metastatic colorectal cancer (mCRC). However, resistance poses a significant challenge to successful therapy. Recently, paraptosis, a non-classical programmed cell death, has garnered increased attention for its potential application value in antitumor treatments. We aimed to identify the essential pathways and signaling molecules involved in paraptosis inhibition and select them as therapeutic targets in cetuximab resistance. Additionally, engineered exosome technology is used as a drug delivery system with both targeted and effector properties. RESULTS: By comparing the differential expression of paraptosis-related genes between drug-resistant colon cancer cells and sensitive cells, it was observed that the paraptosis level induced by cetuximab was significantly downregulated in drug-resistant cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified the focal adhesion kinase (FAK) signaling pathway as a key pathway involved in the suppression of paraptosis. The biological function of FAK in cetuximab-resistant cells was investigated through cell morphology observation, CCK-8 assay, colony formation assay, RT-qPCR, Western Blot, and loss-of-function experiments. The results showed that the FAK signaling pathway was significantly upregulated in cetuximab-resistant colon cancer cells, and siRNA interference targeting FAK could notably inhibit cell proliferation while upregulating the paraptosis level. Based on this, engineered colon cancer cells targeted and FAK siRNA loaded exosomes (CT-Exo-siFAK1) were constructed. In vitro experiments, CT-Exo-siFAK1 could effectively activate paraptosis and inhibit the proliferation of drug-resistant colon cancer cells. In vivo experiments also confirmed that CT-Exo-siFAK1 significantly suppressed tumor growth and metastasis while upregulating the paraptosis level. CONCLUSION: This study suggests that FAK signaling pathway-mediated inhibition of paraptosis levels is crucial in the sensitivity of cetuximab targeted therapy in colon cancer, and the use of engineered exosomes to deliver FAK siRNA may be an effective strategy to reverse cetuximab resistance.

6.
Ann Surg ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557705

RESUMEN

BACKGROUND AND AIMS: Surgery is pivotal in the management of neuroblastoma (NB), particularly in patients with Image-Defined Risk Factors (IDRFs). The International Neuroblastoma Surgical Report Form (INSRF) was introduced to enhance surgical reporting quality and analyze the defining role of extensive surgery in NB. This study reports our experience with INSRF and explores new criteria for evaluating the extent of surgical resection. METHODS: INSRF was deployed to critically analyze 166 patients with abdominal or pelvic NB who underwent surgery at our department between October 2021 and June 2023. Patient demographics, clinical characteristics, surgical datasets, and postoperative complications were described in detail. Receiver operating characteristic (ROC) curves were used to explore a new method to evaluate the extent of resection. A questionnaire was formulated to obtain attitudes/feedback and commentary from surgical oncologists with INSRF. RESULTS: 166 neuroblastoma patients with a median disease age 36.50 months. This study collated 320 INSRF reports. Among the 166 index cases, 137 were documented by two surgeons, with a concordance rate of 16.78%. Items with high inconsistency were (i) the extent of tumor resection (29.20%), (ii) renal vein involvement (25.55%), (iii) abdominal aorta encasement (16.79%), and (iv) mesenteric infiltration (17.52%). According to INSRF, the extent of resection was complete excision in 86 (51.81%) patients, minimal residual tumor < 5 cm3 in 67 (40.36%) patients, and incomplete excision > 5 cm3 in 13 (7.83%) patients. In ROC curve analysis, the number of vessels encased by tumors > 3 had a high predictive value in determining that a tumor could not be completely resected (AUC 0.916, sensitivity 0.838, specificity 0.826) using INSRF as the gold standard reference. The questionnaires showed that surgeons agreed that the extent of resection and tumor involvement of organ/vascular structures were important, while the definition and intervention(s) of intraoperative complications were less operational and understandable. CONCLUSIONS: INSRF has significant clinical application in neuroblastoma surgery. The extent of resection can be predicted based on the number of tumor-encased blood vessels. Supplementary information should be considered with the INSRF to aid practitioner reporting. Multicenter studies are needed to explore the defining role of INSRF in NB surgical management.

7.
Biochem Biophys Res Commun ; 726: 150213, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-38964186

RESUMEN

The F11 receptor (F11R) gene encoding junctional adhesion molecule A has been associated with gastric cancer (GC) and colorectal cancer (CRC), in which its role and regulation remain to be further elucidated. Recently F11R was also identified as a potential target of adenosine-to-inosine (A-to-I) mediated by the adenosine deaminases acting on RNA (ADARs). Herein, using RNA-Seq and experimental validation, our current study revealed an F11R RNA trinucleotide over-edited by ADAR, with its regulation of gene expression and clinical significance in four GC and three CRC cohorts. Our results found an over-edited AAA trinucleotide in an AluSg located in the F11R 3'-untranslated region (3'-UTR), which showed editing levels correlated with elevated ADAR expression across all GC and CRC cohorts in our study. Overexpression and knockdown of ADAR in GC and CRC cells, followed by RNA-Seq and Sanger sequencing, confirmed the ADAR-mediated F11R 3'-UTR trinucleotide editing, which potentially disrupted an RBM45 binding site identified by crosslinking immunoprecipitation sequencing (CLIP-seq) and regulated F11R expression in luciferase reporter assays. Moreover, the F11R trinucleotide editing showed promising predictive performance for diagnosing GC and CRC across GC and CRC cohorts. Our findings thus highlight both the potential biological and clinical significance of an ADAR-edited F11R trinucleotide in GC and CRC, providing new insights into its application as a novel diagnostic biomarker for both cancers.


Asunto(s)
Adenosina Desaminasa , Neoplasias Colorrectales , Regulación Neoplásica de la Expresión Génica , Edición de ARN , Proteínas de Unión al ARN , Neoplasias Gástricas , Humanos , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Estudios de Cohortes , Regiones no Traducidas 3'/genética , Línea Celular Tumoral , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Masculino , Femenino
8.
Small ; 20(16): e2306964, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38072815

RESUMEN

In this study, single-crystalline BiSBr is synthesized using a solution-based approach and conducted a systematic characterization of its photoelectric properties and photovoltaic performances. UV photoelectron spectroscopy and density functional theory (DFT) calculations reveal that BiSBr is an indirect p-type semiconductor, characterized by distinct positions and compositions of the valence band maximum and conduction band minimum. The BiSBr single crystal microrod features a significant electrical conductivity of 14 800 S m-1 along the c-axis, denoting minimal carrier resistance in this direction. For photovoltaic performance assessment, the authors successfully fabricated two homogeneous BiSBr films on TiO2 porous substrates: A microsheet array film via physical vapor deposition (PVD) and solvothermal treatment, and a BiSBr microsheet film via PVD and thermal treatment. The solar cell, comprising a BiSBr microsheet array film with an architecture of fluorine-doped tin oxide FTO/TiO2/BiSBr/(I3 -/I-)/Pt, demonstrated a power conversation efficiency of 1.40%, ≈11 times that of BiSBr microsheet film counterpart. These preliminary results underscore the potential of BiSBr microsheet arrays, producible through low-cost solution processes, as adept light absorbers, enhancing photovoltaic efficiency through effective light scattering and promoting efficient electron-hole separation and transport.

9.
Bioconjug Chem ; 35(5): 653-664, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38593046

RESUMEN

Disorder of complement response is a significant pathogenic factor causing some autoimmune and inflammation diseases. The Ornithodoros moubata Complement Inhibitor (OmCI), a small 17 kDa natural protein, was initially extracted from soft tick salivary glands. The protein was found binding to complement C5 specifically, inhibiting the activation of the complement pathway, which is a successful therapeutic basis of complement-mediated diseases. However, a short half-life due to rapid renal clearance is a common limitation of small proteins for clinical application. In this study, we extended the half-life of OmCI by modifying it with fatty acid, which was a method used to improve the pharmacokinetics of native peptides and proteins. Five OmCI mutants were initially designed, and single-site cysteine mutation was introduced to each of them. After purification, four OmCI mutants were obtained that showed similar in vitro biological activities. Three mutants of them were subsequently coupled with different fatty acids by nucleophilic substitution. In total, 15 modified derivatives were screened and tested for anticomplement activity in vitro. The results showed that coupling with fatty acid would not significantly affect their complement-inhibitory activity (CH50 and AH50). OmCIT90C-CM02 and OmCIT90C-CM05 were validated as the applicable OmCI bioconjugates for further pharmacokinetic assessments, and both showed improved plasma half-life in mice compared with unmodified OmCI (15.86, 17.96 vs 2.57 h). In summary, our data demonstrated that OmCI conjugated with fatty acid could be developed as the potential long-acting C5 complement inhibitor in the clinic.


Asunto(s)
Complemento C5 , Ácidos Grasos , Ornithodoros , Animales , Ácidos Grasos/química , Ratones , Complemento C5/antagonistas & inhibidores , Diseño de Fármacos , Semivida , Proteínas Inactivadoras de Complemento/farmacología , Proteínas Inactivadoras de Complemento/química , Inactivadores del Complemento/farmacología , Inactivadores del Complemento/farmacocinética , Inactivadores del Complemento/química , Humanos
10.
Clin Genet ; 105(1): 52-61, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37822034

RESUMEN

Haplotype-based noninvasive prenatal diagnosis (NIPD) is applicable for various recessive single-gene disorders in proband families. However, a comprehensive exploration of critical factors influencing the assay performance, such as fetal fraction, informative single nucleotide polymorphism (SNP) count, and recombination events, has yet to be performed. It is critical to identify key factors affecting NIPD performance, including its accuracy and success rate, and their impact on clinical diagnostics to guide clinical practice. We conducted a prospective study, recruiting 219 proband families with singleton pregnancies at risk for eight recessive single-gene disorders (Duchenne muscular dystrophy, spinal muscular atrophy, phenylketonuria, methylmalonic acidemia, hemophilia A, hemophilia B, non-syndromic hearing loss, and congenital adrenal hyperplasia) at 7-14 weeks of gestation. Haplotype-based NIPD was performed by evaluating the relative haplotype dosage (RHDO) in maternal circulation, and the results were validated via invasive prenatal diagnosis or newborn follow-ups. Among the 219 families, the median gestational age at first blood draw was 8+5 weeks. Initial testing succeeded for 190 families and failed for 29 due to low fetal fraction (16), insufficient informative SNPs (9), and homologous recombination near pathogenic variation (4). Among low fetal fraction families, successful testing was achieved for 11 cases after a redraw, while 5 remained inconclusive. Test failures linked to insufficient informative SNPs correlated with linkage disequilibrium near the genes, with F8 and MMUT exhibiting the highest associated failure rates (14.3% and 25%, respectively). Homologous recombination was relatively frequent around the DMD and SMN1 genes (8.8% and 4.8%, respectively) but led to detection failure in only 44.4% (4/9) of such cases. All NIPD results from the 201 successful families were consistent with invasive diagnostic findings or newborn follow-up. Fetal fraction, informative SNPs count, and homologous recombination are pivotal to NIPD performance. Redrawing blood effectively improves the success rate for low fetal fraction samples. However, informative SNPs count and homologous recombination rates vary significantly across genes, necessitating careful consideration in clinical practice. We have designed an in silico method based on linkage disequilibrium data to predict the number of informative SNPs. This can identify genomic regions where there might be an insufficient number of SNPs, thereby guiding panel design. With these factors properly accounted for, NIPD is highly accurate and reliable.


Asunto(s)
Distrofia Muscular de Duchenne , Pruebas Prenatales no Invasivas , Embarazo , Femenino , Recién Nacido , Humanos , Lactante , Pruebas Prenatales no Invasivas/métodos , Haplotipos/genética , Estudios Prospectivos , Diagnóstico Prenatal/métodos , Distrofia Muscular de Duchenne/diagnóstico
11.
Cardiovasc Diabetol ; 23(1): 113, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38555454

RESUMEN

BACKGROUND: The hemoglobin glycation index (HGI) is the difference between the observed and predicted values of glycosylated hemoglobin (HbA1c), which is closely associated with a variety of poor prognoses. However, there are still no studies on the correlation between HGI and poor prognosis in patients with critical coronary artery disease. The purpose of this study was to analyze the correlation between HGI and all-cause mortality in patients with critical coronary artery disease using the MIMIC-IV database. METHODS: The HGI was calculated by constructing a linear regression equation between HbA1c and fasting plasma glucose (FPG). A Kaplan‒Meier survival analysis model was constructed based on the HGI quartiles to clarify the differences in all-cause mortality rates between groups, and the log-rank test was used to assess the differences between groups. The hazard ratio (HR) of HGI as a risk factor for outcome events was assessed using the Cox proportional risk model and restricted cubic spline (RCS), with the Q2 group serving as the reference group. RESULTS: A total of 5260 patients were included in this study. The 30-day mortality rate of the patients was 4.94% and the mortality rate within 365 days was 13.12%. A low HGI was significantly associated with 30-day mortality (HR, 1.96; 95% CI, (1.38, 2.78); P < 0.001) and 365-day mortality (HR, 1.48; 95% CI, (1.19, 1.85); P < 0.001) in patients with critical coronary artery disease in the completely adjusted Cox proportional risk model. In addition, high levels of HGI were associated with 365-day mortality (HR, 1.31; 95% CI, (1.02, 1.69); P < 0.05). RCS analysis revealed a U-shaped relationship between HGI and outcome events. According to the stratified analysis, the interaction test revealed that the correlation between HGI and outcome events remained stable. CONCLUSION: There was a significant correlation between HGI and all-cause mortality in patients with critical coronary artery disease, particularly in those with low HGI. HGI can be used as a potential indicator for assessing the short- and long-term risk of mortality in such patients.


Asunto(s)
Enfermedad de la Arteria Coronaria , Diabetes Mellitus Tipo 2 , Humanos , Hemoglobina Glucada , Reacción de Maillard , Hemoglobinas/análisis , Medición de Riesgo , Pronóstico , Glucemia/análisis
12.
BMC Cancer ; 24(1): 754, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38907215

RESUMEN

PURPOSE: Diffuse midline glioma (DMG), H3 K27M-mutant is a type of diffuse high-grade glioma that occurs in the brain midline carrying an extremely poor prognosis under the best efforts of surgery, radiation, and other therapies. For better therapy, we explored the efficacy and toxicity of a novel therapy that combines apatinib and temozolomide in DMG. METHODS: A retrospective analysis of 32 patients with DMG who underwent apatinib plus temozolomide treatment was performed. Apatinib was given 500 mg in adults, 250 mg in pediatric patients once daily. Temozolomide was administered at 200 mg/m2/d according to the standard 5/28 days regimen. The main clinical data included basic information of patients, radiological and pathological characteristics of tumors, treatment, adverse reactions, prognosis. RESULTS: The objective response rate was 24.1%, and the disease control rate was 79.3%. The median PFS of all patients was 5.8 months, and median OS was 10.3 months. A total of 236 cycles of treatment were available for safety assessment and the toxicity of the combination therapy was relatively well tolerated. The most common grade 3 toxicities were myelosuppression including leukopenia (5.08%), neutropenia (4.24%), lymphopenia (2.12%), thrombocytopenia (1.69%) and anemia (1.27%). Grade 4 toxicities included neutropenia (2.12%), thrombocytopenia (2.12%) and proteinuria (1.69%). All the adverse events were relieved after symptomatic treatment or dose reduction. CONCLUSIONS: Apatinib plus temozolomide could be an effective regimen with manageable toxicities and favorable efficacy and may outperform temozolomide monotherapy, particularly in newly diagnosed adults with tumors located outside the pons. The novel therapy deserves further investigation in adult DMG patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Encefálicas , Glioma , Piridinas , Temozolomida , Humanos , Temozolomida/administración & dosificación , Temozolomida/uso terapéutico , Temozolomida/efectos adversos , Femenino , Masculino , Adulto , Piridinas/administración & dosificación , Piridinas/efectos adversos , Piridinas/uso terapéutico , Glioma/tratamiento farmacológico , Glioma/patología , Adolescente , Estudios Retrospectivos , Niño , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Adulto Joven , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Preescolar , Persona de Mediana Edad , Resultado del Tratamiento
13.
Psychol Med ; 54(2): 256-266, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37161677

RESUMEN

BACKGROUND: The incidence of adolescent depressive disorder is globally skyrocketing in recent decades, albeit the causes and the decision deficits depression incurs has yet to be well-examined. With an instrumental learning task, the aim of the current study is to investigate the extent to which learning behavior deviates from that observed in healthy adolescent controls and track the underlying mechanistic channel for such a deviation. METHODS: We recruited a group of adolescents with major depression and age-matched healthy control subjects to carry out the learning task with either gain or loss outcome and applied a reinforcement learning model that dissociates valence (positive v. negative) of reward prediction error and selection (chosen v. unchosen). RESULTS: The results demonstrated that adolescent depressive patients performed significantly less well than the control group. Learning rates suggested that the optimistic bias that overall characterizes healthy adolescent subjects was absent for the depressive adolescent patients. Moreover, depressed adolescents exhibited an increased pessimistic bias for the counterfactual outcome. Lastly, individual difference analysis suggested that these observed biases, which significantly deviated from that observed in normal controls, were linked with the severity of depressive symoptoms as measured by HAMD scores. CONCLUSIONS: By leveraging an incentivized instrumental learning task with computational modeling within a reinforcement learning framework, the current study reveals a mechanistic decision-making deficit in adolescent depressive disorder. These findings, which have implications for the identification of behavioral markers in depression, could support the clinical evaluation, including both diagnosis and prognosis of this disorder.


Asunto(s)
Trastorno Depresivo Mayor , Aprendizaje , Humanos , Adolescente , Refuerzo en Psicología , Recompensa , Condicionamiento Operante
14.
Biotechnol Bioeng ; 121(5): 1518-1531, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38548678

RESUMEN

Clostridium tyrobutyricum is an anaerobe known for its ability to produce short-chain fatty acids, alcohols, and esters. We aimed to develop inducible promoters for fine-tuning gene expression in C. tyrobutyricum. Synthetic inducible promoters were created by employing an Escherichia coli lac operator to regulate the thiolase promoter (PCathl) from Clostridium acetobutylicum, with the best one (LacI-Pto4s) showing a 5.86-fold dynamic range with isopropyl ß- d-thiogalactoside (IPTG) induction. A LT-Pt7 system with a dynamic range of 11.6-fold was then created by combining LacI-Pto4s with a T7 expression system composing of RNA polymerase (T7RNAP) and Pt7lac promoter. Furthermore, two inducible expression systems BgaR-PbgaLA and BgaR-PbgaLB with a dynamic range of ~40-fold were developed by optimizing a lactose-inducible expression system from Clostridium perfringens with modified 5' untranslated region (5' UTR) and ribosome-binding site (RBS). BgaR-PbgaLB was then used to regulate the expressions of a bifunctional aldehyde/alcohol dehydrogenase encoded by adhE2 and butyryl-CoA/acetate Co-A transferase encoded by cat1 in C. tyrobutyricum wild type and Δcat1::adhE2, respectively, demonstrating its efficient inducible gene regulation. The regulated cat1 expression also confirmed that the Cat1-catalyzed reaction was responsible for acetate assimilation in C. tyrobutyricum. The inducible promoters offer new tools for tuning gene expression in C. tyrobutyricum for industrial applications.


Asunto(s)
Clostridium acetobutylicum , Clostridium tyrobutyricum , Clostridium tyrobutyricum/genética , Clostridium tyrobutyricum/metabolismo , Clostridium acetobutylicum/genética , Regiones Promotoras Genéticas/genética , Expresión Génica , Acetatos/metabolismo
15.
Cell Commun Signal ; 22(1): 26, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200543

RESUMEN

BACKGROUND: Cardiolipin (CL) plays a critical role in maintaining mitochondrial membrane integrity and overall mitochondrial homeostasis. Recent studies have suggested that mitochondrial damage resulting from abnormal cardiolipin remodelling is associated with the pathogenesis of diabetic kidney disease (DKD). Acyl-coenzyme A:lyso-cardiolipin acyltransferase-1 (ALCAT1) was confirmed to be involved in the progression of Parkinson's disease, diet-induced obesity and other ageing-related diseases by regulating pathological cardiolipin remodelling. Thus, the purpose of this investigation was to determine the role of ALCAT1-mediated CL remodelling in DKD and to explore the potential underlying mechanism. METHODS: In vivo study, the mitochondrial structure was examined by transmission electron microscopy (TEM). The colocalization of ALCAT1 and synaptopodin was evaluated by double immunolabelling. Western blotting (WB) was performed to assess ALCAT1 expression in glomeruli. Lipidomics analysis was conducted to evaluate the composition of reconstructed cardiolipins. In vitro study, the lipidomics, TEM and WB analyses were similar to those in vivo. Mitochondrial function was evaluated by measuring the mitochondrial membrane potential (MMP) and the production of ATP and ROS. RESULTS: Here, we showed that increased oxidized cardiolipin (ox-CL) and significant mitochondrial damage were accompanied by increased ALCAT1 expression in the glomeruli of patients with DKD. Similar results were found in db/db mouse kidneys and in cultured podocytes stimulated with high glucose (HG). ALCAT1 deficiency effectively prevented HG-induced ox-CL production and mitochondrial damage in podocytes. In contrast, ALCAT1 upregulation enhanced ox-CL levels and podocyte mitochondrial dysfunction. Moreover, treatment with the cardiolipin antioxidant SS-31 markedly inhibited mitochondrial dysfunction and cell injury, and SS-31 treatment partly reversed the damage mediated by ALCAT1 overexpression. We further found that ALCAT1 could mediate the key regulators of mitochondrial dynamics and mitophagy through the AMPK pathway. CONCLUSIONS: Collectively, our studies demonstrated that ALCAT1-mediated cardiolipin remodelling played a crucial role in DKD, which might provide new insights for DKD treatment. Video Abstract.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Enfermedades Mitocondriales , Podocitos , Animales , Humanos , Ratones , Cardiolipinas , Mitocondrias
16.
Protein Expr Purif ; 219: 106475, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38552891

RESUMEN

AA139, a variant of natural antimicrobial peptide (AMP) arenicin-3, displayed potent activity against multidrug-resistant (MDR) and extensively drug-resistant (XDR) Gram-negative bacteria. Nevertheless, there were currently few reports on the bioprocess of AA139, and the yields were less than 5 mg/L. Additionally, it was difficult and expensive to prepare AA139 through chemical synthesis due to its complex structure. These factors have impeded the further research and following clinical application of AA139. Here, we reported a bioprocess for the preparation of AA139, which was expressed in Escherichia coli (E. coli) BL21 (DE3) intracellularly in a soluble form via SUMO (small ubiquitin-related modifier) fusion technology. Then, recombinant AA139 (rAA139, refer to AA139 obtained by recombinant expression in this study) was obtained through the simplified downstream process, which was rationally designed in accordance with the physicochemical characteristics. Subsequently, the expression level of the interest protein was increased by 54% after optimization of high cell density fermentation (HCDF). Finally, we obtained a yield of 56 mg of rAA139 from 1 L culture with a purity of 98%, which represented the highest reported yield of AA139 to date. Furthermore, various characterizations were conducted to confirm the molecular mass, disulfide bonds, and antimicrobial activity of rAA139.


Asunto(s)
Péptidos Antimicrobianos , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos , Péptidos Antimicrobianos/genética , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Péptidos Antimicrobianos/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/farmacología , Fermentación , Expresión Génica
17.
J Surg Res ; 294: 249-256, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37925953

RESUMEN

INTRODUCTION: Cardioplegia and cardiopulmonary bypass (CP/CPB) alters coronary arteriolar response to thromboxane A2 (TXA2) in patients undergoing cardiac surgery. Comorbidities, including hypertension (HTN), can further alter coronary vasomotor tone. This study investigates the effects of HTN on coronary arteriolar response to TXA2 pre and post-CP/CPB and cardiac surgery. MATERIALS AND METHODS: Coronary arterioles pre and post-CP/CPB were dissected from atrial tissue samples in patients with no HTN (NH, n = 9), well-controlled HTN (WC, n = 12), or uncontrolled HTN (UC, n = 12). In-vitro coronary microvascular reactivity was examined in the presence of TXA2 analog U46619 (10-9-10-4M). Protein expression of TXA2 receptor in the harvested right atrial tissue samples were measured by immunoblotting. RESULTS: TXA2 analog U46619 induced dose-dependent contractile responses of coronary arterioles in all groups. Pre-CPB contractile responses to U46619 were significantly increased in microvessels in the UC group compared to the NH group (P < 0.05). The pre-CP/CPB contractile responses of coronary arterioles were significantly diminished post-CP/CPB among the three groups (P < 0.05), but there remained an increased contractile response in the microvessels of the UC group compared to the WC and NH groups (P < 0.05). There were no significant differences in U46619-induced vasomotor tone between patients in the NH and WC groups (P > 0.05). There were no differences in expression of TXA2R among groups. CONCLUSIONS: Poorly controlled HTN is associated with increased contractile response of coronary arterioles to TXA2. This alteration may contribute to worsened recovery of coronary microvascular function in patients with poorly controlled HTN after CP/CPB and cardiac surgery.


Asunto(s)
Fibrilación Atrial , Procedimientos Quirúrgicos Cardíacos , Hipertensión , Humanos , Tromboxano A2/metabolismo , Tromboxano A2/farmacología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/metabolismo , Vasos Coronarios , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Puente Cardiopulmonar , Hipertensión/complicaciones
18.
Analyst ; 149(12): 3425-3432, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38720619

RESUMEN

Antimicrobial resistance poses a serious threat to human health due to the high morbidity and mortality caused by drug-resistant microbial infections. Therefore, the development of rapid, sensitive and selective identification methods is key to improving the survival rate of patients. In this paper, a sandwich-type electrochemical DNA biosensor based on a polyadenine-DNA tetrahedron probe was constructed. The key experimental conditions were optimized, including the length of polyadenine, the concentration of the polyadenine DNA tetrahedron, the concentration of the signal probe and the hybridization time. At the same time, poly-avidin-HRP80 was used to enhance the electrochemical detection signal. Finally, excellent biosensor performance was achieved, and the detection limit for the synthetic DNA target was as low as 1 fM. In addition, we verified the practicability of the system by analyzing E. coli with the MCR-1 plasmid and realized multi-channel detection of the drug resistance genes MCR-1, blaNDM, blaKPC and blaOXA. With the ideal electrochemical interface, the polyA-based biosensor exhibits excellent stability, which provides powerful technical support for the rapid detection of antibiotic-resistant strains in the field.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Escherichia coli , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Límite de Detección , Hibridación de Ácido Nucleico , Humanos , ADN Bacteriano/genética , ADN Bacteriano/análisis
19.
Bioorg Med Chem ; 100: 117630, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38330849

RESUMEN

Tirzepatide, the first approved dual GLP-1/GIP receptor agonist (RA), has achieved better clinical outcomes than other GLP-1RAs. However, it is an imbalanced dual GIP/GLP-1 RA, and it remains unclear whether the degree of imbalance is optimal. Here, we present a novel long-acting dual GLP-1/GIP RA that exhibits better activity than tirzepatide toward GLP-1R. A candidate conjugate, D314, identified via peptide design, synthesis, conjugation, and experimentation, was evaluated using chronic studies in db/db and diet induced obese (DIO) mice. D314 achieved favorable blood glucose and body weight-lowering effects, equal to those of tirzepatide. Its half-life in dogs (T1/2: 78.3 ± 14.01 h) reveals its suitability for once-weekly administration in humans. This preclinical study suggests the potential role of D314 as an effective agent for treating T2DM and obesity.


Asunto(s)
Diabetes Mellitus Tipo 2 , Péptido 1 Similar al Glucagón , Receptores de la Hormona Gastrointestinal , Animales , Perros , Humanos , Ratones , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/agonistas , Hipoglucemiantes/farmacología , Obesidad/tratamiento farmacológico , Receptores de la Hormona Gastrointestinal/agonistas , Receptores de la Hormona Gastrointestinal/uso terapéutico
20.
Methods ; 218: 149-157, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37572767

RESUMEN

Deep convolutional neural networks (DCNNs) have shown remarkable performance in medical image segmentation tasks. However, medical images frequently exhibit distribution discrepancies due to variations in scanner vendors, operators, and image quality, which pose significant challenges to the robustness of trained models when applied to unseen clinical data. To address this issue, domain generalization methods have been developed to enhance the generalization ability of DCNNs. Feature space-based data augmentation methods have been proven effective in improving domain generalization, but they often rely on prior knowledge or assumptions, which can limit the diversity of source domain data. In this study, we propose a novel random feature augmentation (RFA) method to diversify source domain data at the feature level without prior knowledge. Specifically, our RFA method perturbs domain-specific information while preserving domain-invariant information, thereby adequately diversifying the source domain data. Furthermore, we propose a dual-branches invariant synergistic learning strategy to capture domain-invariant information from the augmented features of RFA, enabling DCNNs to learn a more generalized representation. We evaluate our proposed method on two challenging medical image segmentation tasks, optic cup/disc segmentation on fundus images and prostate segmentation on MRI images. Extensive experimental results demonstrate the superior performance of our method over state-of-the-art domain generalization methods.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Masculino , Humanos
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