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1.
Toxicol Sci ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38745431

RESUMEN

The ubiquitous existence of microplastics and nanoplastics raises concerns about their potential impact on the human reproductive system. Limited data exists on microplastics within the human reproductive system and their potential consequences on sperm quality. Our objectives were to quantify and characterize the prevalence and composition of microplastics within both canine and human testes and investigate potential associations with the sperm count, and weights of testis and epididymis. Using advanced sensitive Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS), we quantified 12 types of microplastics within 47 canine and 23 human testes. Data on reproductive organ weights, and sperm count in dogs were collected. Statistical analyses, including descriptive analysis, correlational analysis, and multivariate linear regression analyses were applied to investigate the association of microplastics with reproductive functions. Our study revealed the presence of microplastics in all canine and human testes, with significant inter-individual variability. Mean total microplastic levels were 122.63 µg/g in dogs and 328.44 µg/g in humans. Both humans and canines exhibit relatively similar proportions of the major polymer types, with PE being dominant. Furthermore, a negative correlation between specific polymers such as PVC and PET and the normalized weight of the testis was observed. These findings highlight the pervasive presence of microplastics in the male reproductive system in both canine and human testes, with potential consequences on male fertility.

2.
Cancer Immunol Immunother ; 73(7): 116, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713408

RESUMEN

OBJECTIVES: Nivolumab is approved as adjuvant therapy for resected stage III/IV melanoma based on the phase 3 CheckMate 238 trial. This analysis compared outcomes from CheckMate 238 with those from the real-world Flatiron Health electronic health record-derived de-identified database in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab. MATERIALS: Outcomes included baseline characteristics, overall survival (OS) in the CheckMate 238 cohort (randomization until death or last known alive), and real-world overall survival (rwOS) in the Flatiron Health cohort (nivolumab initiation until death or data cutoff). rwOS was compared with OS using unadjusted and adjusted Cox proportional hazards models. Inverse probability of treatment weighting (IPTW) was combined with the adjusted model to reduce baseline discrepancies. RESULTS: The CheckMate 238 and real-world cohorts included 369 and 452 patients, respectively (median age, 56.0 and 63.0 years; median follow-up, 61.4 vs. 25.5 months). rwOS was not different from OS in the unadjusted (hazard ratio [HR] 1.27; 95% CI 0.92-1.74), adjusted (HR 1.01; 95% CI 0.67-1.54), and adjusted IPTW (HR 1.07; 95% CI 0.70-1.63) analyses. In the adjusted analysis, 2-year OS and rwOS rates were 84%. Median OS and rwOS were not reached. After IPTW, OS and rwOS were not different (HR 1.07; 95% CI 0.70-1.64). CONCLUSIONS: In this comparative analysis, OS in the CheckMate 238 trial was similar to rwOS in the Flatiron Health database after adjustments in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab, validating the trial results.


Asunto(s)
Melanoma , Estadificación de Neoplasias , Nivolumab , Humanos , Melanoma/tratamiento farmacológico , Melanoma/mortalidad , Melanoma/patología , Melanoma/cirugía , Nivolumab/uso terapéutico , Femenino , Masculino , Persona de Mediana Edad , Quimioterapia Adyuvante/métodos , Anciano , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Resultado del Tratamiento , Antineoplásicos Inmunológicos/uso terapéutico , Adulto
3.
Toxicol Lett ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38768835

RESUMEN

Aging increases susceptibility to lung disease, but the topic is understudied, especially in relation to environmental exposures with the bulk of rodent studies using young adults. This study aims to define the pulmonary toxicity of naphthalene (NA) and the impacts of a dietary antioxidant, ergothioneine (ET), in the liver and lungs of middle-aged mice. NA causes a well-characterized pattern of conducting airway epithelial injury in the lung in young adult mice, but NA's toxicity has not been characterized in middle-aged mice, aged 1 - 1.5 years. ET is a dietary antioxidant that is synthesized by bacteria and fungi. The ET transporter (ETT), SLC22A4, is upregulated in tissues that experience high levels of oxidative stress. In this study, middle-aged male and female C57BL/6J mice, maintained on an ET-free synthetic diet from conception, were gavaged with 70mg/kg of ET for five consecutive days. On day 8, the mice were exposed to a single intraperitoneal NA dose of 50, 100, 150, or 200mg/kg. At 24hours post NA injection samples were collected and analyzed for ET concentration and reduced (GSH) and oxidized glutathione (GSSG) concentrations. Histopathology, morphometry, and gene expression were examined. Histopathology of mice exposed to 100mg/kg of NA suggests reduction in toxicity in the terminal airways of both male (p ≤ 0.001) and female (p ≤ 0.05) middle-aged mice by the ET pretreatment. Our findings in this study are the first to document the toxicity of NA in middle-aged mice and show some efficacy of ET in reducing NA toxicity.

4.
Adv Mater ; : e2402435, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38723286

RESUMEN

III-V semiconductors possess high mobility, high frequency response, and detection sensitivity, making them potentially attractive for beyond-silicon electronics applications. However, the traditional heteroepitaxy of III-V semiconductors is impeded by a significant lattice mismatch and the necessity for extreme vacuum and high temperature conditions, thereby impeding their in situ compatibility with flexible substrates and silicon-based circuits. In this study, a novel approach is presented for fabricating ultrathin InSb single-crystal nanosheets on arbitrary substrates with a thickness as thin as 2.4 nm using low-thermal-budget van der Waals (vdW) epitaxy through chemical vapor deposition (CVD). In particular, in situ growth has been successfully achieved on both silicon-based substrates and flexible polyimide (PI) substrates. Notably, the growth temperature required for InSb nanosheets (240 °C) is significantly lower than that employed in back-end-of-line processes (400 °C). The field effect transistor devices based on fabricated ultrathin InSb nanosheets exhibit ultra-high on-off ratio exceeding 108 and demonstrate minimal gate leakage currents. Furthermore, these ultrathin InSb nanosheets display p-type characteristics with hole mobilities reaching up to 203 cm2 V-1 s-1 at room temperatures. This study paves the way for achieving heterogeneous integration of III-V semiconductors and facilitating their application in flexible electronics.

5.
Biochem Pharmacol ; 224: 116247, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697311

RESUMEN

Current therapeutic options for renal cell carcinoma (RCC) are very limited, which is largely due to inadequate comprehension of molecular pathological mechanisms as well as RCC's resistance to chemotherapy. Dual-specificity phosphatase 6 (DUSP6) has been associated with numerous human diseases. However, its role in RCC is not well understood. Here, we show that diminished DUSP6 expression is linked to RCC progression and unfavorable prognosis. Mechanistically, DUSP6 serves as a tumor suppressor in RCC by intervening the TAF10 and BSCL2 via the ERK-AKT pathway. Further, DUSP6 is also transcriptionally regulated by HNF-4a. Moreover, docking experiments have indicated that DUSP6 expression is enhanced when bound by Calcium saccharate, which also inhibits RCC cell proliferation, metabolic rewiring, and sunitinib resistance. In conclusion, our study identifies Calcium saccharate as a prospective pharmacological therapeutic approach for RCC.


Asunto(s)
Antineoplásicos , Carcinoma de Células Renales , Fosfatasa 6 de Especificidad Dual , Glucólisis , Neoplasias Renales , Proteínas Proto-Oncogénicas c-akt , Sunitinib , Humanos , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Sunitinib/farmacología , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Glucólisis/efectos de los fármacos , Glucólisis/fisiología , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Fosfatasa 6 de Especificidad Dual/metabolismo , Fosfatasa 6 de Especificidad Dual/genética , Antineoplásicos/farmacología , Ratones , Ratones Desnudos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Masculino
6.
Mol Metab ; : 101957, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38740087

RESUMEN

Compromised hepatic fatty acid oxidation (FAO) has been observed in human MASH patients and animal models of MASLD/MASH. It remains poorly understood how and when the hepatic FAO pathway is suppressed during the progression of MASLD towards MASH. Hepatic ChREBP⍺ is a classical lipogenic transcription factor that responds to the intake of dietary sugars. We examined its role in regulating hepatocyte fatty acid oxidation (FAO) and the impact of hepatic Chrebpa deficiency on sensitivity to diet-induced MASLD/MASH in mice. We discovered that hepatocyte ChREBP⍺ is both necessary and sufficient to maintain FAO in a cell-autonomous manner independently of its DNA-binding activity. Supplementation of synthetic PPAR⍺/δ agonist is sufficient to restore FAO in Chrebp-/- primary murine hepatocytes. Hepatic ChREBP⍺ was decreased in mouse models of diet-induced MAFSLD/MASH and in patients with MASH. Hepatocyte-specific Chrebp⍺ knockout impaired FAO, aggravated liver steatosis and inflammation, leading to early-onset fibrosis in response to diet-induced MASH. Conversely, liver overexpression of ChREBP⍺-WT or its non-lipogenic mutant enhanced FAO, reduced lipid deposition, and alleviated liver injury, inflammation, and fibrosis. RNA-seq analysis identified the CYP450 epoxygenase (CYP2C50) pathway of arachidonic acid metabolism as a novel target of ChREBP⍺. Over-expression of CYP2C50 partially restores hepatic FAO in primary hepatocytes with Chrebp⍺ deficiency and attenuates preexisting MASH in the livers of hepatocyte-specific Chrebp⍺-deleted mice. Thus, our findings support the protective role of hepatocyte ChREBPa against diet-induced MASLD/MASH in mouse models in part via promoting CYP2C50-driven FAO.

7.
Open Med (Wars) ; 19(1): 20240951, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38623457

RESUMEN

Objective: In the present study, we investigated the impact of left atrial appendage closure (LAAC) following catheter ablation (CA) on the left atrial structure and functioning of patients with paroxysmal atrial fibrillation (AF). Methods: Patients with paroxysmal AF were enrolled in this single-center prospective cohort study between April 2015 and July 2021; 353 patients received CA alone, while 93 patients received CA in combination with Watchman LAAC. We used age, gender, CHA2DS2-VASc, and HAS-BLED scores as well as other demographic variables to perform propensity score matching. Patients with paroxysmal AF were randomly assigned to the CA combined with Watchman LAAC group (combined treatment group) and the simple CA group, with 89 patients in each group. The left atrial structure, reserve, ventricular diastole, and pump functions and their changes in patients were assessed using routine Doppler echocardiography and 2D speckle tracking echocardiography over the course of a 1-year follow-up. Results: At 1-week follow-up, the reserve, ventricular diastole, and pump functions of the left atrium (LA) increased in both groups; these functions were gradually restored at the 1- to 3-month follow-up; they were close to or returned to their pre-operative levels at the 3-month follow-up; and no significant differences were found compared with the pre-operative levels at the 12-month follow-up. In the first 3 months, the reserve (Ƹ, SRs) and pump functions (SRa) in the combined treatment group decreased significantly when compared with the simple CA group, and the differences were statistically significant. Conclusion: Patients with paroxysmal AF may experience a short term, partial effect of LAAC on LA reserve and pump functions, which are gradually restored and the effect disappears by 12 months.

8.
Angew Chem Int Ed Engl ; : e202402949, 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644342

RESUMEN

Photoimmunotherapy is a promising cancer treatment modality. While potent 1-e- oxidative species are known to induce immunogenic cell death (ICD), they are also associated with unspecific oxidation and collateral tissue damage. This difficulty may be addressed by post-generation radical reinforcement. Namely, non-oxidative radicals are first generated and subsequently activated into powerful oxidative radicals to induce ICD. Here, we developed a photo-triggered molecular donor (NPCD565) of nitrosoperoxycarbonate (ONOOCO2-), the first of its class to our knowledge, and further evaluated its feasibility for immunotherapy. Upon irradiation of NPCD565 by light within a broad spectral region from ultraviolet to red, ONOOCO2- is released along with a bright rhodamine dye (RD565), whose fluorescence is a reliable and convenient build-in reporter for the localization, kinetics, and dose of ONOOCO2- generation. Upon photolysis of NPCD565 in 4T1 cells, damage-associated molecular patterns (DAMPs) indicative of ICD were observed and confirmed to exhibit immunogenicity by induced maturation of dendritic cells. In vivo studies with a bilateral tumor-bearing mouse model showcased the potent tumor-killing capability of NPCD565 of the primary tumors and growth suppression of the distant tumors. This work unveils the potent immunogenicity of ONOOCO2-, and its donor (NPCD565) has broad potential for photo-immunotherapy of cancer.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38668843

RESUMEN

Our study aims to find the relevant mechanism of Mume Fructus in the treatment of triple-negative breast cancer (TNBC) by network pharmacology analysis and experimental validation. The effective compounds of Mume Fructus and TNBC-related target genes were imported into Cytoscape to construct a Mume Fructus-effective compounds-disease target network. The common targets of Mume Fructus and TNBC were determined by drawing Venn diagrams. Then, the intersection targets were transferred to the STRING database to construct a protein-protein interaction (PPI) network. To investigate the mechanism of Mume Fructus in treatment of TNBC, breast cancer cell (MDA-MB-231) was treated with Mume Fructus and/or transfected with small interference RNA-PKM2(siPKM2). CCK-8 assay, cell clonal formation assay, transwell, flow cytometry, qRT-PCR, and western blotting were performed. Eight effective compounds and 145 target genes were obtained, and the Mume Fructus- effective compounds-disease target network was constructed. Then through the analysis of the PPI network, we obtained 10 hub genes including JUN, MAPK1, RELA, AKT1, FOS, ESR1, IL6, MAPK8, RXRA, and MYC. KEGG enrichment analysis showed that JUN, MAPK1, RELA, FOS, ESR1, IL6, MAPK8, and RXRA were enriched in the Th17 cell differentiation signaling pathway. Loss of PKM2 and Mume Fructus both inhibited the malignant phenotype of MDA-MB-231 cells. And siPKM2 further aggravated the Mume Fructus inhibition of malignancy of breast cancer cells. Network pharmacology analysis suggests that Mume Fructus has multiple therapeutic targets for TNBC and may play a therapeutic role by modulating the immune microenvironment of breast cancer.

10.
Abdom Radiol (NY) ; 49(5): 1584-1592, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38502213

RESUMEN

PURPOSE: We sought to summarize the value of contrast-enhanced computed tomography (CECT) in the differential diagnosis of bladder paraganglioma (BPG) and bladder cancer. METHODS: The medical records of 19 patients with BPG (13 males, 6 females) and 56 patients with bladder cancer (49 males, 7 females) between November 2007 and June 2023 were retrospectively reviewed. All patients underwent unenhanced and contrast-enhanced CT scanning. RESULTS: Patient age (46.4 ± 11.1 years vs. 58.6 ± 16.0 years), tumor calcification (1/19 vs. 18/56), stalk (0/19 vs. 10/56), internal vessels (15/19 vs. 19/56) and the enlarged adjacent supplying artery (14/19 vs. 10/56) were significantly different between BPG and bladder cancer (P < 0.05). The CT value in the corticomedullary phase (92.4 ± 16.6 HU vs. 64.0 ± 14.5 HU) and the contrast-enhanced value in the corticomedullary phase (54.5 ± 17.4 HU vs. 28.5 ± 12.8 HU) were significantly greater in BPG patients than in bladder cancer patients (P < 0.001), with corresponding area under the curve values of 0.930 and 0.912, respectively. The optimal cutoff values were 83.2 HU and 38.5 HU, respectively. A CT value > 83.2 HU in the corticomedullary phase and a contrast-enhanced CT value > 38.5 HU in the corticomedullary phase were used to indicate BPG with sensitivities of 78.9% and 89.5%, respectively, and specificities of 94.6% and 75.0%, respectively. CONCLUSION: The corticomedullary phase of CECT plays an important role in the preoperative differential diagnosis of BPG and bladder cancer.


Asunto(s)
Medios de Contraste , Paraganglioma , Tomografía Computarizada por Rayos X , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Masculino , Femenino , Persona de Mediana Edad , Diagnóstico Diferencial , Paraganglioma/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Vejiga Urinaria/diagnóstico por imagen
11.
J Cell Biol ; 223(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429999

RESUMEN

Cholesterol from low-density lipoprotein (LDL) can be transported to many organelle membranes by non-vesicular mechanisms involving sterol transfer proteins (STPs). Fatty acid-binding protein (FABP) 7 was identified in our previous study searching for new regulators of intracellular cholesterol trafficking. Whether FABP7 is a bona fide STP remains unknown. Here, we found that FABP7 deficiency resulted in the accumulation of LDL-derived cholesterol in lysosomes and reduced cholesterol levels on the plasma membrane. A crystal structure of human FABP7 protein in complex with cholesterol was resolved at 2.7 Å resolution. In vitro, FABP7 efficiently transported the cholesterol analog dehydroergosterol between the liposomes. Further, the silencing of FABP3 and 8, which belong to the same family as FABP7, caused robust cholesterol accumulation in lysosomes. These two FABP proteins could transport dehydroergosterol in vitro as well. Collectively, our results suggest that FABP3, 7, and 8 are a new class of STPs mediating cholesterol egress from lysosomes.


Asunto(s)
Colesterol , Proteínas de Unión a Ácidos Grasos , Lisosomas , Humanos , Membrana Celular/metabolismo , Colesterol/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Lisosomas/metabolismo , Esteroles/metabolismo
12.
Heliyon ; 10(5): e27234, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38463812

RESUMEN

Cellular immunotherapy is a crucial aspect of current tumor immunotherapy, though it presents several challenges such as immune cell dysfunction, limited recognition of neoantigens, and inadequate lymphocyte infiltration into the tumor microenvironment. This study proposes a novel approach utilizing a combination of dendritic cell (DC)-based cellular immunotherapy and a photothermal nanoadjuvant black phosphorus (BP) nanoparticles to overcome these challenges. A new platform called PLGA@BP-R848, which consists of modifying poly-(lactic-co-glycolic acid) (PLGA) onto BP nanosheets loading the immune adjuvant R848. The PLGA@BP-R848 nanoparticles demonstrated exceptional drug delivery and release capabilities, as well as a photothermal effect, biocompatibility, and the ability to activate the mitochondrial apoptotic pathway Blc-2-Bax-Cytochrome c-caspase-3 and inhibit the PI3K-AKT-mTOR signaling pathway. In a hepatocellular carcinoma mouse model, the binding of PLGA@BP-R848 nanoparticles and dendritic cells primed with GPC3 peptides, successfully induced a systemic anti-tumor immune response. PLGA@BP-R848 nanoparticles bolster immune cell infiltration into tumors and induce cancer cell apoptosis. The synergistic therapy involving dendritic cells and photothermal nanoadjuvant effectively suppressed tumor growth, and facilitated the formation of tertiary lymphatic structures (TLS) in tumors. This study presents a novel approach in using photothermal nanoadjuvants to advance antitumor effect of cellular immunotherapy, such as DCs therapy.

13.
ACS Nano ; 18(11): 7739-7768, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38456396

RESUMEN

Silicon transistors are approaching their physical limit, calling for the emergence of a technological revolution. As the acknowledged ultimate version of transistor channels, 2D semiconductors are of interest for the development of post-Moore electronics due to their useful properties and all-in-one potentials. Here, the promise and current status of 2D semiconductors and transistors are reviewed, from materials and devices to integrated applications. First, we outline the evolution and challenges of silicon-based integrated circuits, followed by a detailed discussion on the properties and preparation strategies of 2D semiconductors and van der Waals heterostructures. Subsequently, the significant progress of 2D transistors, including device optimization, large-scale integration, and unconventional devices, are presented. We also examine 2D semiconductors for advanced heterogeneous and multifunctional integration beyond CMOS. Finally, the key technical challenges and potential strategies for 2D transistors and integrated circuits are also discussed. We envision that the field of 2D semiconductors and transistors could yield substantial progress in the upcoming years and hope this review will trigger the interest of scientists planning their next experiment.

14.
ACS Nano ; 18(11): 8475-8483, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38456704

RESUMEN

The magnetic skyrmions exhibit intriguing topological behaviors, holding promise for future applications in the realm of spintronic devices. Despite recent advancements, achieving spontaneous magnetic skyrmions and topological transitions in magnets featuring uniaxial magnetic anisotropy, particularly at elevated temperatures (>100 K), remains a challenging endeavor. Here, single-crystal Fe5Si3 nanorods with the central symmetry and uniaxial magnetic anisotropy were successfully synthesized on a mica substrate through chemical vapor deposition, which exhibit a high Curie temperature (TC) of about 372 K. The real-time observation, facilitated by Lorentz transmission electron microscopy, revealed the spontaneous formation of magnetic skyrmions and evolution of domains in focused ion beam-prepared Fe5Si3 thin foils. Moreover, Fe5Si3 device transport measurements expose notable magnetoresistance (MR) effects, enabling the interchange between positive and negative MR across specific temperature settings. These results offer various potential avenues for exploring diverse topological spin textures and their formation mechanisms, indicating inventive applications for iron-silicon alloy in the realm of spintronics.

15.
Sci Adv ; 10(11): eadk9474, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38478614

RESUMEN

Memristors are considered promising energy-efficient artificial intelligence hardware, which can eliminate the von Neumann bottleneck by parallel in-memory computing. The common imperfection-enabled memristors are plagued with critical variability issues impeding their commercialization. Reported approaches to reduce the variability usually sacrifice other performances, e.g., small on/off ratios and high operation currents. Here, we demonstrate an unconventional Ag-doped nonimperfection diffusion channel-enabled memristor in van der Waals indium phosphorus sulfide, which can combine ultralow variabilities with desirable metrics. We achieve operation voltage, resistance, and on/off ratio variations down to 3.8, 2.3, and 6.9% at their extreme values of 0.2 V, 1011 ohms, and 108, respectively. Meanwhile, the operation current can be pushed from 1 nA to 1 pA at the scalability limit of 6 nm after Ag doping. Fourteen Boolean logic functions and convolutional image processing are successfully implemented by the memristors, manifesting the potential for logic-in-memory devices and efficient non-von Neumann accelerators.

16.
PLoS Biol ; 22(3): e3002514, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38483978

RESUMEN

The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a system is a powerful tool in gene editing; however, crRNA-DNA mismatches might induce unwanted cleavage events, especially at the distal end of the PAM. To minimize this limitation, we engineered a hyper fidelity AsCas12a variant carrying the mutations S186A/R301A/T315A/Q1014A/K414A (termed HyperFi-As) by modifying amino acid residues interacting with the target DNA and crRNA strand. HyperFi-As retains on-target activities comparable to wild-type AsCas12a (AsCas12aWT) in human cells. We demonstrated that HyperFi-As has dramatically reduced off-target effects in human cells, and HyperFi-As possessed notably a lower tolerance to mismatch at the position of the PAM-distal region compared with the wild type. Further, a modified single-molecule DNA unzipping assay at proper constant force was applied to evaluate the stability and transient stages of the CRISPR/Cas ribonucleoprotein (RNP) complex. Multiple states were sensitively detected during the disassembly of the DNA-Cas12a-crRNA complexes. On off-target DNA substrates, the HyperFi-As-crRNA was harder to maintain the R-loop complex state compared to the AsCas12aWT, which could explain exactly why the HyperFi-As has low off-targeting effects in human cells. Our findings provide a novel version of AsCas12a variant with low off-target effects, especially capable of dealing with the high off-targeting in the distal region from the PAM. An insight into how the AsCas12a variant behaves at off-target sites was also revealed at the single-molecule level and the unzipping assay to evaluate multiple states of CRISPR/Cas RNP complexes might be greatly helpful for a deep understanding of how CRISPR/Cas behaves and how to engineer it in future.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Humanos , Sistemas CRISPR-Cas/genética , ARN Guía de Sistemas CRISPR-Cas , Endonucleasas/genética , Endonucleasas/metabolismo , ADN/genética
17.
Front Biosci (Landmark Ed) ; 29(3): 92, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38538272

RESUMEN

Phosphoglycerate kinase 1 (PGK1) serves as a pivotal enzyme in the cellular glycolysis pathway, facilitating adenosine-triphosphate (ATP) production in tumor cells and driving the Warburg effect. PGK1 generates ATP through the reversible phosphorylation reaction of 1,3-bisphosphoglycerate (1,3-BPG) to Mg-adenosine-5'-diphosphate (Mg-ADP). In addition to its role in regulating cellular metabolism, PGK1 plays a pivotal role in autophagy induction, regulation of the tricarboxylic acid cycle (TCA), and various mechanisms including tumor cell drug resistance, and so on. Given its multifaceted functions within cells, the involvement of PGK1 in many types of cancer, including breast cancer, astrocytoma, metastatic colon cancer, and pancreatic ductal adenocarcinoma, is intricate. Notably, PGK1 can function as an intracellular protein kinase to coordinate tumor growth, migration, and invasion via posttranslational modifications (PTMs). Furthermore, elevated expression levels of PGK1 have been observed in cancer tissues, indicating its association with unfavorable treatment outcomes and prognosis. This review provides a comprehensive summary of PGK1's expression pattern, structural features, functional properties, involvement in PTMs, and interaction with tumors. Additionally highlighted are the prospects for developing and applying related inhibitors that confirm the indispensable value of PGK1 in tumor progression.


Asunto(s)
Neoplasias del Colon , Fosfoglicerato Quinasa , Humanos , Adenosina/metabolismo , Adenosina Trifosfato/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/tratamiento farmacológico , Fosfoglicerato Quinasa/genética , Fosfoglicerato Quinasa/metabolismo , Fosforilación
18.
Biochem Pharmacol ; 223: 116172, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552852

RESUMEN

The enzyme tryptophan 2,3-dioxygenase (TDO2) has been implicated in the dysregulation across a variety of human cancers. Despite this association, the implications of TDO2 in the progression of bladder cancer have eluded thorough understanding. In this study, we demonstrate that TDO2 expression is notably elevated in bladder cancer tissues and serves as an unfavorable prognostic factor for overall survival. Through a series of biological functional assays, we have determined that TDO2 essentially enhances cell proliferation, metastatic potential, and imparts a decreased sensitivity to the chemotherapeutic agent cisplatin. Our mechanistic investigations reveal that TDO2 augments aryl hydrocarbon receptor (AhR) signaling pathways and subsequently upregulates the expression of SPARC and FILIP1L. Importantly, we have identified a positive correlation between TDO2 levels and the basal/squamous subtype of bladder cancer, and we provide evidence to suggest that TDO2 expression is modulated by the tumor suppressors RB1 and TP53. From a therapeutic perspective, we demonstrate that the targeted inhibition of TDO2 with the molecular inhibitor 680C91 markedly attenuates tumor growth and metastasis while concurrently enhancing the efficacy of cisplatin. These findings open a new therapeutic avenue for the management of bladder cancer.


Asunto(s)
Triptófano Oxigenasa , Neoplasias de la Vejiga Urinaria , Humanos , Cisplatino/farmacología , Cisplatino/uso terapéutico , Cisplatino/metabolismo , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Triptófano/metabolismo , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Osteonectina/genética
19.
Nano Lett ; 24(6): 2118-2124, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38305203

RESUMEN

Ferroelectric two-dimensional (2D) materials with a high transition temperature are highly desirable for new physics and next-generation memory electronics. However, the long-range polar order of ferroelectrics will barely persist when the thickness reaches the nanoscale. In this work, we synthesized 2D CuCrS2 nanosheets with thicknesses down to one unit cell via van der Waals epitaxy in a chemical vapor deposition system. A combination of transmission electron microscopy, second-harmonic generation, and Raman spectroscopy measurements confirms the R3m space group and noncentrosymmetric structure. Switchable ferroelectric domains and obvious ferroelectric hysteresis loops were created and visualized by piezoresponse force microscopy. Theoretical calculation helps us understand the mechanism of ferroelectric switching in CuCrS2 nanosheets. Finally, we fabricated a ferroelectric memory device that achieves an on/off ratio of ∼102 and remains stable after 2000 s, indicating its applicability in novel nanoelectronics. Overall, 2D CuCrS2 nanosheets exhibit excellent ferroelectric properties at the nanoscale, showing great promise for next-generation devices.

20.
iScience ; 27(2): 108966, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38327779

RESUMEN

Nanobody, referred to the variable domain of heavy-chain-only antibodies, has several advantages such as small size and feasible Escherichia coli expression, making them promising for scientific research and therapies. Conventional nanobody screening and expression methods often suffer from the need for subcloning into expression vectors and amplification-induced diversity loss. Here, we developed an integrated method for simultaneous screening and expression. Nanobody libraries were cloned and secretly expressed in the culture medium. Target-specific nanobodies were isolated through 1-3 rounds of dilution and regrowth following the Poisson distribution. This ensured no dismissal of positive clones, with populations of positive clones increasing over 10-fold in each dilution round. Ultimately, we isolated 5 nanobodies against death domain receptor 5 and 5 against Pyrococcus furiosus DNA polymerase directly from their immunized libraries. Notably, our approach enables nanobody screening without specialized instruments, demonstrating broad applicability in routine monoclonal nanobody production for diverse biomedical applications.

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