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1.
J Environ Sci (China) ; 148: 515-528, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095185

RESUMEN

The reduction of nitrobenzene to aniline is very important for both pollution control and chemical synthesis. Nevertheless, difficulties still remain in developing a catalytic system having high efficiency and selectivity for the production of aniline. Herein, it was found that PdO nanoparticles highly dispersed on TiO2 support (PdO/TiO2) functioned as a highly efficient catalyst for the reduction of nitrobenzene in the presence of NaBH4. Under favorable conditions, 95% of the added nitrobenzene (1 mmol/L) was reduced within 1 min with an ultra-low apparent activation energy of 10.8 kJ/mol by using 0.5%PdO/TiO2 as catalysts and 2 mmol/L of NaBH4 as reductants, and the selectivity to aniline even reached up to 98%. The active hydrogen species were perceived as dominant species during the hydrogenation of nitrobenzene by the results of isotope labeling experiments and ESR spectroscopic. A mechanism was proposed as follows: PdO activates the nitro groups and leads to in-situ generation of Pd, and the generated Pd acts as the reduction sites to produce active hydrogen species. In this catalytic system, nitrobenzene prefers to be adsorbed on the PdO nanoparticles of the PdO/TiO2 composite. Subsequently, the addition of NaBH4 results in in-situ generation of a Pd/PdO/TiO2 composite from the PdO/TiO2 composite, and the Pd nanoclusters would activate NaBH4 to generate active hydrogen species to attack the adsorbed nitro groups. This work will open up a new approach for the catalytic transfer hydrogenation of nitrobenzene to aniline in green chemistry.


Asunto(s)
Compuestos de Anilina , Nitrobencenos , Paladio , Titanio , Nitrobencenos/química , Compuestos de Anilina/química , Titanio/química , Hidrogenación , Catálisis , Paladio/química , Modelos Químicos
2.
bioRxiv ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39091883

RESUMEN

Patients with castration-resistant prostate cancer (CRPC) are generally unresponsive to tumor targeted and immunotherapies. Whether genetic alterations acquired during the evolution of CRPC impact immune and immunotherapy responses is largely unknown. Using our innovative electroporation-based mouse models, we generated distinct genetic subtypes of CRPC found in patients and uncovered unique immune microenvironments. Specifically, mouse and human prostate tumors with MYC amplification and p53 disruption had weak cytotoxic lymphocyte infiltration and an overall dismal prognosis. MYC and p53 cooperated to induce tumor intrinsic secretion of VEGF, which by signaling through VEGFR2 expressed on CD8+ T cells, could directly inhibit T cell activity. Targeting VEGF-VEGFR2 signaling in vivo led to CD8+ T cell-mediated tumor and metastasis growth suppression and significantly increased overall survival in MYC and p53 altered CPRC. VEGFR2 blockade also led to induction of PD-L1, and in combination with PD-L1 immune checkpoint blockade produced anti-tumor efficacy in multiple preclinical CRPC mouse models. Thus, our results identify a genetic mechanism of immune suppression through VEGF signaling in prostate cancer that can be targeted to reactivate immune and immunotherapy responses in an aggressive subtype of CRPC. Significance: Though immune checkpoint blockade (ICB) therapies can achieve curative responses in many treatment-refractory cancers, they have limited efficacy in CRPC. Here we identify a genetic mechanism by which VEGF contributes to T cell suppression, and demonstrate that VEGFR2 blockade can potentiate the effects of PD-L1 ICB to immunologically treat CRPC.

3.
Int J Mol Sci ; 25(15)2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39125826

RESUMEN

Watermelon is one of the most important edible plants worldwide. Owing to its special cultivation conditions, watermelon is exposed to many biological and abiotic stresses during its development. Lectin receptor-like kinases (LecRLKs) are plant-specific membrane proteins that play important roles in sensing and responding to environmental stimuli. Although the LecRLK gene family has been identified in a variety of plants, a comprehensive analysis has not yet been undertaken in watermelon. In this study, 61 putative LecRLK genes were identified in watermelon, consisting of 36 G-type, 24 L-type, and 1 C-type LecRLK genes. They were distributed in clusters on chromosomes, and members from the same subfamily were mostly clustered together. The analysis of the phylogenetic tree and conserved motif indicated that there were obvious differences among three ClaLecRLK subfamilies, and there was also rich diversity in the C-terminal within subfamilies. A collinear analysis revealed that the evolution of the ClaLecRLK gene family in different Cucurbitaceae crops was asynchronous. Furthermore, the analysis of the ClaLecRLK protein structure showed that not all proteins contained signal peptides and a single transmembrane domain. A subcellular localization assay confirmed that the number and position of transmembrane domains did not affect ClaLecRLK protein localization in cells. Transcriptome data revealed distinct expression patterns of LecRLK genes of watermelon in various tissues, and their responses to different fungi infection were also significantly different. Finally, the potential binding sites of the ClaLecRLK genes targeted by miRNA were predicted. This study enhances the understanding of the characteristics and functions of the LecRLK gene family in watermelon and opens up the possibility of exploring the roles that LecRLK genes may play in the life cycle of Cucurbitaceae plants.


Asunto(s)
Citrullus , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Citrullus/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilación de la Expresión Génica , Genoma de Planta , Estudio de Asociación del Genoma Completo , Familia de Multigenes , Cromosomas de las Plantas/genética
4.
Mol Biol Cell ; : mbcE24030122, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39083354

RESUMEN

Adaptation to environmental stress requires coordination between stress-defense programs and cell cycle progression. The immediate response to many stressors has been well characterized, but how cells survive in challenging environments long-term is unknown. Here, we investigate the role of the stress-activated phosphatase calcineurin (CN) in adaptation to chronic CaCl2 stress in Saccharomyces cerevisiae. We find that prolonged exposure to CaCl2 impairs mitochondrial function and demonstrate that cells respond to this stressor using two CN-dependent mechanisms - one that requires the downstream transcription factor Crz1 and another that is Crz1-independent. Our data indicate that CN maintains cellular fitness by promoting cell cycle progression and preventing CaCl2-induced cell death. When Crz1 is present, transient CN activation suppresses cell death and promotes adaptation despite high levels of mitochondrial loss. However, in the absence of Crz1, prolonged activation of CN prevents mitochondrial loss and further cell death by upregulating glutathione (GSH) biosynthesis genes thereby mitigating damage from reactive oxygen species. These findings illustrate how cells maintain long-term fitness during chronic stress and suggest that CN promotes adaptation in challenging environments by multiple mechanisms.

5.
Biochim Biophys Acta Mol Basis Dis ; 1870(7): 167438, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39059591

RESUMEN

Colorectal cancer (CRC) is one of the most common malignancies worldwide. Double-strand break (DSB) is the most severe type of DNA damage. However, few reviews have thoroughly examined the involvement of DSB in CRC. Latest researches demonstrated that DSB repair plays an important role in CRC. For example, DSB-related genes such as BRCA1, Ku-70 and DNA polymerase theta (POLQ) are associated with the occurrence of CRC, and POLQ even showed to affect the prognosis and resistance for radiotherapy in CRC. This review comprehensively summarizes the DSB role in CRC, explores the mechanisms and discusses the association with CRC treatment. Four pathways for DSB have been demonstrated. 1. Nonhomologous end joining (NHEJ) is the major pathway. Its core genes including Ku70 and Ku80 bind to broken ends and recruit repair factors to form a complex that mediates the connection of DNA breaks. 2. Homologous recombination (HR) is another important pathway. Its key genes including BRCA1 and BRCA2 are involved in finding, pairing, and joining broken ends, and ensure the restoration of breaks in a normal double-stranded DNA structure. 3. Single-strand annealing (SSA) pathway, and 4. POLθ-mediated end-joining (alt-EJ) is a backup pathway. This paper elucidates roles of the DSB repair pathways in CRC, which could contribute to the development of potential new treatment approaches and provide new opportunities for CRC treatment and more individualized treatment options based on therapeutic strategies targeting these DNA repair pathways.


Asunto(s)
Proteína BRCA1 , Neoplasias Colorrectales , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/terapia , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , ADN Polimerasa theta , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética , Reparación del ADN , ADN Polimerasa Dirigida por ADN/metabolismo , ADN Polimerasa Dirigida por ADN/genética , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Animales
6.
Syst Biol Reprod Med ; 70(1): 218-227, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39013025

RESUMEN

Sperm-derived genetic material contributes half of the genome to the embryo, hence it's crucial to investigate which sperm parameter influences blastocyst formation in the intracytoplasmic sperm injection (ICSI) cycles with severe male infertility. The retrospective study analyzed 296 ICSI cycles with severe oligoasthenoteratozoospermia (OAT) and 99 ICSI cycles with preimplantation genetic testing for aneuploidy (PGT-A). Following the correlation analysis, data stratifications were performed in the OAT ICSI subgroup. The results showed that the matching blastocyst in the OAT ICSI cycles had inferior sperm parameters. DFI and sperm morphology had an influence on the blastocyst formation rate and the high-quality blastocysts formation rate on Day6, but no significant effect on the blastocyst development on Day 5. The high-quality blastocysts formation rate and ratio of high-quality blastocyst on Day 6 were demonstrably better in the subgroup of the teratozoospermic morphology when DFI was within the normal range. In the case of the normal sperm morphology, no statistically significant difference was found in blastocyst development, although there were numerical differences within different DFI subgroups. It was concluded that the blastocyst quality and development declined with the decreased sperm qualities.


Asunto(s)
Blastocisto , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides , Humanos , Masculino , Estudios Retrospectivos , Femenino , Adulto , Infertilidad Masculina/terapia , Infertilidad Masculina/fisiopatología , Embarazo , Desarrollo Embrionario , Oligospermia/terapia , Oligospermia/fisiopatología
7.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38928029

RESUMEN

Metabolic engineering enables oilseed crops to be more competitive by having more attractive properties for oleochemical industrial applications. The aim of this study was to increase the erucic acid level and to produce wax ester (WE) in seed oil by genetic transformation to enhance the industrial applications of B. carinata. Six transgenic lines for high erucic acid and fifteen transgenic lines for wax esters were obtained. The integration of the target genes for high erucic acid (BnFAE1 and LdPLAAT) and for WEs (ScWS and ScFAR) in the genome of B. carinata cv. 'Derash' was confirmed by PCR analysis. The qRT-PCR results showed overexpression of BnFAE1 and LdPLAAT and downregulation of RNAi-BcFAD2 in the seeds of the transgenic lines. The fatty acid profile and WE content and profile in the seed oil of the transgenic lines and wild type grown in biotron were analyzed using gas chromatography and nanoelectrospray coupled with tandem mass spectrometry. A significant increase in erucic acid was observed in some transgenic lines ranging from 19% to 29% in relation to the wild type, with a level of erucic acid reaching up to 52.7%. Likewise, the transgenic lines harboring ScFAR and ScWS genes produced up to 25% WE content, and the most abundant WE species were 22:1/20:1 and 22:1/22:1. This study demonstrated that metabolic engineering is an effective biotechnological approach for developing B. carinata into an industrial crop.


Asunto(s)
Brassica , Ácidos Erucicos , Ésteres , Ingeniería Metabólica , Plantas Modificadas Genéticamente , Semillas , Ceras , Ácidos Erucicos/metabolismo , Ingeniería Metabólica/métodos , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Ceras/metabolismo , Ésteres/metabolismo , Semillas/genética , Semillas/metabolismo , Brassica/genética , Brassica/metabolismo , Ácidos Grasos/metabolismo , Aceites de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
J Integr Med ; 22(4): 503-514, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38849220

RESUMEN

OBJECTIVE: Studies have demonstrated that cycloastragenol induces antitumor effects in prostate, colorectal and gastric cancers; however, its efficacy for inhibiting the proliferation of lung cancer cells is largely unexplored. This study explores the efficacy of cycloastragenol for inhibiting non-small cell lung cancer (NSCLC) and elucidates the underlying molecular mechanisms. METHODS: The effects of cycloastragenol on lung cancer cell proliferation were assessed using an adenosine triphosphate monitoring system based on firefly luciferase and clonogenic formation assays. Cycloastragenol-induced apoptosis in lung cancer cells was evaluated using dual staining flow cytometry with an annexin V-fluorescein isothiocyanate/propidium iodide kit. To elucidate the role of cycloastragenol in the induction of apoptosis, apoptosis-related proteins were examined using Western blots. Immunofluorescence and Western blotting were used to determine whether cycloastragenol could induce autophagy in lung cancer cells. Genetic techniques, including small interfering RNA technology, were used to investigate the underlying mechanisms. The effects against lung cancer and biosafety of cycloastragenol were evaluated using a mouse subcutaneous tumor model. RESULTS: Cycloastragenol triggered both autophagy and apoptosis. Specifically, cycloastragenol promoted apoptosis by facilitating the accumulation of phorbol-12-myristate-13-acetate-induced protein 1 (NOXA), a critical apoptosis-related protein. Moreover, cycloastragenol induced a protective autophagy response through modulation of the adenosine 5'-monophosphate-activated protein kinase (AMPK)/unc-51-like autophagy-activating kinase (ULK1)/mammalian target of rapamycin (mTOR) pathway. CONCLUSION: Our study sheds new light on the antitumor efficacy and mechanism of action of cycloastragenol in NSCLC. This insight provides a scientific basis for exploring combination therapies that use cycloastragenol and inhibiting the AMPK/ULK1/mTOR pathway as a promising approach to combating lung cancer. Please cite this article as follows: Zhu LH, Liang YP, Yang L, Zhu F, Jia LJ, Li HG. Cycloastragenolinduces apoptosis and protective autophagy through AMPK/ULK1/mTOR axis in human non-small celllung cancer cell lines. J Integr Med. 2024; 22(4): 504-515.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Apoptosis , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Serina-Treonina Quinasas TOR , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Serina-Treonina Quinasas TOR/metabolismo , Apoptosis/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Animales , Autofagia/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ratones Desnudos , Ratones Endogámicos BALB C , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética
9.
Int J Gen Med ; 17: 1707-1712, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706751

RESUMEN

Background: There have been several studies regarding the susceptibility of A20 gene SNPs (rs2230926 and rs5029937) in rheumatoid arthritis (RA). However, little is known about the association between polymorphisms in the A20 promoter and RA. The aim of this study was to investigate the characteristics of A20 promoter polymorphisms and the association between these polymorphisms and clinical significance in Chinese RA patients. Methods: PCR and sequencing were used to identify A20 gene polymorphisms in peripheral blood mononuclear cells (PBMCs) from 123 RA cases and 31 healthy individuals. Results: Only one SNP (rs5029924) in the A20 gene promoter was identified in RA patients and healthy individuals. 6 patients who carried heterozygous rs5029924 (3918C>T) together with heterozygous rs5029937 (11,571 G>T) and rs2230926 (12,486 T>G, Phe127Cys) suffered from joints deformity or refractory RA. Conclusion: We reported the A20 promoter polymorphism rs5029924 in RA patients for the first time. rs5029924 concomitant with rs2230926 and rs5029937 may be a prognostic predictor for joint deformity or refractory RA.

10.
BMC Public Health ; 24(1): 1310, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745161

RESUMEN

BACKGROUND: This study examined the knowledge, attitude, and practice (KAP) toward allergic rhinitis (AR) among parents. METHODS: This cross-sectional study enrolled parents of children with AR at Ningbo Hangzhou Bay Hospital between December 2022 and March 2023. A self-administered questionnaire was developed to collect the demographic characteristics, knowledge, attitudes, and practices toward AR. RESULTS: This study included 480 questionnaires, and 78.33% were mothers. The mean knowledge, attitude, and practice scores were 13.49 ± 6.62 (possible range: 0-24), 33.99 ± 3.40 (possible range: 8-40), and 21.52 ± 3.36 (possible range: 5-26), indicating poor knowledge, positive attitudes, and proactive practice. Multivariable logistic regression analysis showed living in urban areas in Ningbo outside Hangzhou Bay New Zone (OR = 4.33, 95%CI: 1.52-12.34, P = 0.006), living in rural areas in Ningbo (OR = 2.15, 95%CI: 1.00-4.59, P = 0.049), being self-employed (OR = 1.99, 95%CI: 1.00-3.95, P = 0.049), monthly income per capita ≥ 20,000 CNY (OR = 1.89, 95%CI: 1.02-3.47, P = 0.042), child with one biological sibling (OR = 0.48, 95%CI: 0.30-0.78, P = 0.003), and ≥ 6 times hospital visits for AR (OR = 2.32, 95%CI: 1.40-3.86, P = 0.001) were independently associated with adequate knowledge. The knowledge (OR = 1.09, 95%CI: 1.05-1.13, P < 0.001) and ≥ 6 times hospital visits for AR (OR = 1.84, 95%CI: 1.06-3.22, P = 0.032) were independently associated with a positive attitude. The knowledge (OR = 1.08, 95%CI: 1.04-1.13, P = 0.001), attitude (OR = 1.41, 95%CI: 1.28-1.55, P < 0.001), monthly income per capita ≥ 20,000 CNY (OR = 3.59, 95%CI: 1.49-8.65, P = 0.004), no previous hospital visit for AR (OR = 0.35, 95%CI: 0.16-0.78, P = 0.003), and ≥ 6 times hospital visits for AR (OR = 0.40, 95%CI: 0.20-0.81, P = 0.011) were independently associated with the practice scores. CONCLUSIONS: The parents of children with AR had poor knowledge but positive attitudes and proactive practice toward AR. This study has identified a need for specific and reliable information initiatives to be introduced as a means of reducing parental concern and ensuring evidence-based strategies for managing children with AR.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Padres , Rinitis Alérgica , Humanos , China , Femenino , Masculino , Estudios Transversales , Adulto , Padres/psicología , Encuestas y Cuestionarios , Persona de Mediana Edad , Niño , Adulto Joven
11.
Autophagy ; : 1-16, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38726865

RESUMEN

AQP3 (aquaporin 3 (Gill blood group)), a member of the AQP family, is an aquaglyceroporin which transports water, glycerol and small solutes across the plasma membrane. Beyond its role in fluid transport, AQP3 plays a significant role in regulating various aspects of tumor cell behavior, including cell proliferation, migration, and invasion. Nevertheless, the underlying regulatory mechanism of AQP3 in tumors remains unclear. Here, for the first time, we report that AQP3 is a direct target for ubiquitination by the SCFFBXW5 complex. In addition, we revealed that downregulation of FBXW5 significantly induced AQP3 expression to prompt macroautophagic/autophagic cell death in hepatocellular carcinoma (HCC) cells. Mechanistically, AQP3 accumulation induced by FBXW5 knockdown led to the degradation of PDPK1/PDK1 in a lysosomal-dependent manner, thus inactivating the AKT-MTOR pathway and inducing autophagic death in HCC. Taken together, our findings revealed a previously undiscovered regulatory mechanism through which FBXW5 degraded AQP3 to suppress autophagic cell death via the PDPK1-AKT-MTOR axis in HCC cells.Abbreviation: BafA1: bafilomycin A1; CQ: chloroquine; CRL: CUL-Ring E3 ubiquitin ligases; FBXW5: F-box and WD repeat domain containing 5; HCC: hepatocellular carcinoma; HSPA8/HSC70: heat shock protein family A (Hsp70) member 8; 3-MA: 3-methyladenine; PDPK1/PDK1: 3-phosphoinositide dependent protein kinase 1; RBX1/ROC1: ring-box 1; SKP1: S-phase kinase associated protein 1; SCF: SKP1-CUL1-F-box protein.

12.
Nat Commun ; 15(1): 4410, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38782979

RESUMEN

Pancreatic ß cells secrete insulin in response to glucose elevation to maintain glucose homeostasis. A complex network of inter-organ communication operates to modulate insulin secretion and regulate glucose levels after a meal. Lipids obtained from diet or generated intracellularly are known to amplify glucose-stimulated insulin secretion, however, the underlying mechanisms are not completely understood. Here, we show that a Drosophila secretory lipase, Vaha (CG8093), is synthesized in the midgut and moves to the brain where it concentrates in the insulin-producing cells in a process requiring Lipid Transfer Particle, a lipoprotein originating in the fat body. In response to dietary fat, Vaha stimulates insulin-like peptide release (ILP), and Vaha deficiency results in reduced circulatory ILP and diabetic features including hyperglycemia and hyperlipidemia. Our findings suggest Vaha functions as a diacylglycerol lipase physiologically, by being a molecular link between dietary fat and lipid amplified insulin secretion in a gut-brain axis.


Asunto(s)
Encéfalo , Proteínas de Drosophila , Drosophila melanogaster , Secreción de Insulina , Insulina , Animales , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Encéfalo/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Eje Cerebro-Intestino/fisiología , Lipasa/metabolismo , Lipasa/genética , Grasas de la Dieta/metabolismo , Glucosa/metabolismo , Cuerpo Adiposo/metabolismo , Lipoproteína Lipasa/metabolismo , Lipoproteína Lipasa/genética , Masculino
13.
Phys Med Biol ; 69(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38722545

RESUMEN

Objective.In this work, we aim to propose an accurate and robust spectrum estimation method by synergistically combining x-ray imaging physics with a convolutional neural network (CNN).Approach.The approach relies on transmission measurements, and the estimated spectrum is formulated as a convolutional summation of a few model spectra generated using Monte Carlo simulation. The difference between the actual and estimated projections is utilized as the loss function to train the network. We contrasted this approach with the weighted sums of model spectra approach previously proposed. Comprehensive studies were performed to demonstrate the robustness and accuracy of the proposed approach in various scenarios.Main results.The results show the desirable accuracy of the CNN-based method for spectrum estimation. The ME and NRMSE were -0.021 keV and 3.04% for 80 kVp, and 0.006 keV and 4.44% for 100 kVp, superior to the previous approach. The robustness test and experimental study also demonstrated superior performances. The CNN-based approach yielded remarkably consistent results in phantoms with various material combinations, and the CNN-based approach was robust concerning spectrum generators and calibration phantoms.Significance. We proposed a method for estimating the real spectrum by integrating a deep learning model with real imaging physics. The results demonstrated that this method was accurate and robust in estimating the spectrum, and it is potentially helpful for broad x-ray imaging tasks.


Asunto(s)
Método de Montecarlo , Redes Neurales de la Computación , Fantasmas de Imagen , Rayos X , Procesamiento de Imagen Asistido por Computador/métodos
14.
Cell Rep ; 43(5): 114211, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38722741

RESUMEN

Multiple myeloma (MM) remains an incurable hematological malignancy demanding innovative therapeutic strategies. Targeting MYC, the notorious yet traditionally undruggable oncogene, presents an appealing avenue. Here, using a genome-scale CRISPR-Cas9 screen, we identify the WNK lysine-deficient protein kinase 1 (WNK1) as a regulator of MYC expression in MM cells. Genetic and pharmacological inhibition of WNK1 reduces MYC expression and, further, disrupts the MYC-dependent transcriptional program. Mechanistically, WNK1 inhibition attenuates the activity of the immunoglobulin heavy chain (IgH) enhancer, thus reducing MYC transcription when this locus is translocated near the MYC locus. WNK1 inhibition profoundly impacts MM cell behaviors, leading to growth inhibition, cell-cycle arrest, senescence, and apoptosis. Importantly, the WNK inhibitor WNK463 inhibits MM growth in primary patient samples as well as xenograft mouse models and exhibits synergistic effects with various anti-MM compounds. Collectively, our study uncovers WNK1 as a potential therapeutic target in MM.


Asunto(s)
Mieloma Múltiple , Proteínas Proto-Oncogénicas c-myc , Proteína Quinasa Deficiente en Lisina WNK 1 , Mieloma Múltiple/genética , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Mieloma Múltiple/metabolismo , Proteína Quinasa Deficiente en Lisina WNK 1/metabolismo , Proteína Quinasa Deficiente en Lisina WNK 1/genética , Humanos , Animales , Ratones , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Cadenas Pesadas de Inmunoglobulina/genética , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Cell Rep ; 43(4): 114041, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38573857

RESUMEN

CD24 is frequently overexpressed in ovarian cancer and promotes immune evasion by interacting with its receptor Siglec10, present on tumor-associated macrophages, providing a "don't eat me" signal that prevents targeting and phagocytosis by macrophages. Factors promoting CD24 expression could represent novel immunotherapeutic targets for ovarian cancer. Here, using a genome-wide CRISPR knockout screen, we identify GPAA1 (glycosylphosphatidylinositol anchor attachment 1), a factor that catalyzes the attachment of a glycosylphosphatidylinositol (GPI) lipid anchor to substrate proteins, as a positive regulator of CD24 cell surface expression. Genetic ablation of GPAA1 abolishes CD24 cell surface expression, enhances macrophage-mediated phagocytosis, and inhibits ovarian tumor growth in mice. GPAA1 shares structural similarities with aminopeptidases. Consequently, we show that bestatin, a clinically advanced aminopeptidase inhibitor, binds to GPAA1 and blocks GPI attachment, resulting in reduced CD24 cell surface expression, increased macrophage-mediated phagocytosis, and suppressed growth of ovarian tumors. Our study highlights the potential of targeting GPAA1 as an immunotherapeutic approach for CD24+ ovarian cancers.


Asunto(s)
Aciltransferasas , Antígeno CD24 , Neoplasias Ováricas , Fagocitosis , Animales , Femenino , Humanos , Ratones , Aciltransferasas/metabolismo , Amidohidrolasas/metabolismo , Amidohidrolasas/genética , Antígeno CD24/metabolismo , Línea Celular Tumoral , Glicosilfosfatidilinositoles/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Neoplasias Ováricas/terapia
16.
bioRxiv ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38562881

RESUMEN

Adaptation to environmental stress requires coordination between stress-defense programs and cell cycle progression. The immediate response to many stressors has been well characterized, but how cells survive in challenging environments long-term is unknown. Here, we investigate the role of the stress-activated phosphatase calcineurin (CN) in adaptation to chronic CaCl2 stress in Saccharomyces cerevisiae. We find that prolonged exposure to CaCl2 impairs mitochondrial function and demonstrate that cells respond to this stressor using two CN-dependent mechanisms - one that requires the downstream transcription factor Crz1 and another that is Crz1-independent. Our data indicate that CN maintains cellular fitness by promoting cell cycle progression and preventing CaCl2-induced cell death. When Crz1 is present, transient CN activation suppresses cell death and promotes adaptation despite high levels of mitochondrial loss. However, in the absence of Crz1, prolonged activation of CN prevents mitochondrial loss and further cell death by upregulating glutathione (GSH) biosynthesis genes thereby mitigating damage from reactive oxygen species. These findings illustrate how cells maintain long-term fitness during chronic stress and suggest that CN promotes adaptation in challenging environments by multiple mechanisms.

17.
Leukemia ; 38(5): 951-962, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553571

RESUMEN

Relapse in T-cell acute lymphoblastic leukemia (T-ALL) may signify the persistence of leukemia-initiating cells (L-ICs). Ectopic TAL1/LMO expression defines the largest subset of T-ALL, but its role in leukemic transformation and its impact on relapse-driving L-ICs remain poorly understood. In TAL1/LMO mouse models, double negative-3 (DN3; CD4-CD8-CD25+CD44-) thymic progenitors harbored L-ICs. However, only a subset of DN3 leukemic cells exhibited L-IC activity, and studies linking L-ICs and chemotolerance are needed. To investigate L-IC heterogeneity, we used mouse models and applied single-cell RNA-sequencing and nucleosome labeling techniques in vivo. We identified a DN3 subpopulation with a cell cycle-restricted profile and heightened TAL1/LMO2 activity, that expressed genes associated with stemness and quiescence. This dormant DN3 subset progressively expanded throughout leukemogenesis, displaying intrinsic chemotolerance and enrichment in genes linked to minimal residual disease. Examination of TAL/LMO patient samples revealed a similar pattern in CD7+CD1a- thymic progenitors, previously recognized for their L-IC activity, demonstrating cell cycle restriction and chemotolerance. Our findings substantiate the emergence of dormant, chemotolerant L-ICs during leukemogenesis, and demonstrate that Tal1 and Lmo2 cooperate to promote DN3 quiescence during the transformation process. This study provides a deeper understanding of TAL1/LMO-induced T-ALL and its clinical implications in therapy failure.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas con Dominio LIM , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteína 1 de la Leucemia Linfocítica T Aguda , Animales , Ratones , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteína 1 de la Leucemia Linfocítica T Aguda/metabolismo , Proteína 1 de la Leucemia Linfocítica T Aguda/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas con Dominio LIM/metabolismo , Proteínas con Dominio LIM/genética , Timo/metabolismo , Timo/patología , Humanos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología
18.
World J Clin Oncol ; 15(2): 329-355, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38455135

RESUMEN

BACKGROUND: Pyroptosis impacts the development of malignant tumors, yet its role in colorectal cancer (CRC) prognosis remains uncertain. AIM: To assess the prognostic significance of pyroptosis-related genes and their association with CRC immune infiltration. METHODS: Gene expression data were obtained from The Cancer Genome Atlas (TCGA) and single-cell RNA sequencing dataset GSE178341 from the Gene Expression Omnibus (GEO). Pyroptosis-related gene expression in cell clusters was analyzed, and enrichment analysis was conducted. A pyroptosis-related risk model was developed using the LASSO regression algorithm, with prediction accuracy assessed through K-M and receiver operating characteristic analyses. A nomogram predicting survival was created, and the correlation between the risk model and immune infiltration was analyzed using CIBERSORTx calculations. Finally, the differential expression of the 8 prognostic genes between CRC and normal samples was verified by analyzing TCGA-COADREAD data from the UCSC database. RESULTS: An effective pyroptosis-related risk model was constructed using 8 genes-CHMP2B, SDHB, BST2, UBE2D2, GJA1, AIM2, PDCD6IP, and SEZ6L2 (P < 0.05). Seven of these genes exhibited differential expression between CRC and normal samples based on TCGA database analysis (P < 0.05). Patients with higher risk scores demonstrated increased death risk and reduced overall survival (P < 0.05). Significant differences in immune infiltration were observed between low- and high-risk groups, correlating with pyroptosis-related gene expression. CONCLUSION: We developed a pyroptosis-related prognostic model for CRC, affirming its correlation with immune infiltration. This model may prove useful for CRC prognostic evaluation.

19.
J Fungi (Basel) ; 10(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38535238

RESUMEN

Pinus massoniana Lamb. is an important, common afforestation and timber tree species in China. Species of Pestalotiopsis are well-known pathogens of needle blight. In this study, the five representative strains were isolated from needle blight from needles of Pi. massoniana in Nanjing, Jiangsu, China. Based on multi-locus phylogenetic analyses of the three genomic loci (ITS, TEF1, and TUB2), in conjunction with morphological characteristics, a new species, namely Pestalotiopsis jiangsuensis sp. nov., was described and reported. Pathogenicity tests revealed that the five representative strains of the species described above were pathogenic to Pi. massoniana. The study revealed the diversity of pathogenic species of needle blight on Pi. massoniana. This is the first report of needle blight caused by P. jiangsuensis on Pi. massoniana in China and worldwide. This provides useful information for future research on management strategies of this disease.

20.
J Agric Food Chem ; 72(8): 4464-4475, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38376143

RESUMEN

Theobromine is an important quality component in tea plants (Camellia sinensis), which is produced from 7-methylxanthine by theobromine synthase (CsTbS), the key rate-limiting enzyme in theobromine biosynthetic pathway. Our transcriptomics and widely targeted metabolomics analyses suggested that CsMYB114 acted as a potential hub gene involved in the regulation of theobromine biosynthesis. The inhibition of CsMYB114 expression using antisense oligonucleotides (ASO) led to a 70.21% reduction of theobromine level in leaves of the tea plant, which verified the involvement of CsMYB114 in theobromine biosynthesis. Furthermore, we found that CsMYB114 was located in the nucleus of the cells and showed the characteristic of a transcription factor. The dual luciferase analysis, a yeast one-hybrid assay, and an electrophoretic mobility shift assay (EMSA) showed that CsMYB114 activated the transcription of CsTbS, through binding to CsTbS promoter. In addition, a microRNA, miR828a, was identified that directly cleaved the mRNA of CsMYB114. Therefore, we conclude that CsMYB114, as a transcription factor of CsTbS, promotes the production of theobromine, which is inhibited by miR828a through cleaving the mRNA of CsMYB114.


Asunto(s)
Camellia sinensis , Camellia sinensis/genética , Camellia sinensis/metabolismo , Teobromina/metabolismo , Cafeína/metabolismo , Hojas de la Planta/metabolismo , Té/metabolismo , Factores de Transcripción/genética , ARN Mensajero/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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