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1.
Proc Natl Acad Sci U S A ; 120(4): e2213727120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36656854

RESUMEN

The myophage possesses a contractile tail that penetrates its host cell envelope. Except for investigations on the bacteriophage T4 with a rather complicated structure, the assembly pattern and tail contraction mechanism of myophage remain largely unknown. Here, we present the fine structure of a freshwater Myoviridae cyanophage Pam3, which has an icosahedral capsid of ~680 Å in diameter, connected via a three-section neck to an 840-Å-long contractile tail, ending with a three-module baseplate composed of only six protein components. This simplified baseplate consists of a central hub-spike surrounded by six wedge heterotriplexes, to which twelve tail fibers are covalently attached via disulfide bonds in alternating upward and downward configurations. In vitro reduction assays revealed a putative redox-dependent mechanism of baseplate assembly and tail sheath contraction. These findings establish a minimal myophage that might become a user-friendly chassis phage in synthetic biology.


Asunto(s)
Myoviridae , Ensamble de Virus , Bacteriófago T4/química , Cápside , Proteínas de la Cápside/química , Microscopía por Crioelectrón , Myoviridae/química
2.
Prostate ; 84(6): 605-619, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38375594

RESUMEN

BACKGROUND: Metastatic castration-resistant prostate cancer (CRPC), the most refractory prostate cancer, inevitably progresses and becomes unresponsive to hormone therapy, revealing a pressing unmet need for this disease. Novel agents targeting HDAC6 and microtubule dynamics can be a potential anti-CRPC strategy. METHODS: Cell proliferation was examined in CRPC PC-3 and DU-145 cells using sulforhodamine B assay and anchorage-dependent colony formation assay. Flow cytometric analysis of propidium iodide staining was used to determine cell-cycle progression. Cell-based tubulin polymerization assay and confocal immunofluorescence microscopic examination determine microtubule assembly/disassembly status. Protein expressions were determined using Western blot analysis. RESULTS: A total of 82 novel derivatives targeting HDAC6 were designed and synthesized, and Compound 25202 stood out, showing the highest efficacy in blocking HDAC6 (IC50, 3.5 nM in enzyme assay; IC50, 1.0 µM in antiproliferative assay in CRPC cells), superior to tubastatin A (IC50, 5.4 µM in antiproliferative assay). The selectivity and superiority of 25202 were validated by examining the acetylation of both α-tubulin and histone H3, detecting cell apoptosis and HDACs enzyme activity assessment. Notably, 25202 but not tubastatin A significantly decreased HDAC6 protein expression. 25202 prolonged mitotic arrest through the detection of cyclin B1 upregulation, Cdk1 activation, mitotic phosphoprotein levels, and Bcl-2 phosphorylation. Compound 25202 did not mimic docetaxel in inducing tubulin polymerization but disrupted microtubule organization. Compound 25202 also increased the phosphorylation of CDC20, BUB1, and BUBR1, indicating the activation of the spindle assembly checkpoint (SAC). Moreover, 25202 profoundly sensitized cisplatin-induced cell death through impairment of cisplatin-evoked DNA damage response and DNA repair in both ATR-Chk1 and ATM-Chk2 pathways. CONCLUSION: The data suggest that 25202 is a novel selective and potent HDAC6 inhibitor. Compound 25202 blocks HDAC6 activity and interferes microtubule dynamics, leading to SAC activation and mitotic arrest prolongation that eventually cause apoptosis of CRPC cells. Furthermore, 25202 sensitizes cisplatin-induced cell apoptosis through impeding DNA damage repair pathways.


Asunto(s)
Cisplatino , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Cisplatino/farmacología , Neoplasias de la Próstata Resistentes a la Castración/patología , Tubulina (Proteína)/metabolismo , Puntos de Control de la Fase M del Ciclo Celular , Línea Celular Tumoral , Apoptosis , Proliferación Celular , Microtúbulos/metabolismo , Microtúbulos/patología , Histona Desacetilasa 6/metabolismo
3.
Brief Bioinform ; 23(3)2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35419596

RESUMEN

Cellular senescence (CS), a state of permanent growth arrest, is intertwined with tumorigenesis. Due to the absence of specific markers, characterizing senescence levels and senescence-related phenotypes across cancer types remain unexplored. Here, we defined computational metrics of senescence levels as CS scores to delineate CS landscape across 33 cancer types and 29 normal tissues and explored CS-associated phenotypes by integrating multiplatform data from ~20 000 patients and ~212 000 single-cell profiles. CS scores showed cancer type-specific associations with genomic and immune characteristics and significantly predicted immunotherapy responses and patient prognosis in multiple cancers. Single-cell CS quantification revealed intra-tumor heterogeneity and activated immune microenvironment in senescent prostate cancer. Using machine learning algorithms, we identified three CS genes as potential prognostic predictors in prostate cancer and verified them by immunohistochemical assays in 72 patients. Our study provides a comprehensive framework for evaluating senescence levels and clinical relevance, gaining insights into CS roles in cancer- and senescence-related biomarker discovery.


Asunto(s)
Neoplasias de la Próstata , Microambiente Tumoral , Senescencia Celular/genética , Genómica , Humanos , Inmunoterapia , Masculino , Neoplasias de la Próstata/genética , Microambiente Tumoral/genética
4.
Lupus ; 33(4): 403-408, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38407846

RESUMEN

OBJECTIVE: Interleukin-18 (IL-18) is a proinflammatory cytokine. This study aims to determine whether there is a causal relationship between circulating IL-18 concentrations and the risk of inflammatory and autoimmune diseases. METHODS: We collected significant single nucleotide polymorphisms (SNPs) associated with circulating IL-18 levels (p < 5 × 10-8) as instrumental variables (IVs) from a genome-wide association study (GWAS) involving 21,758 individuals of European descent. We mainly employed the inverse-variance weighed (IVW) method of two-sample Mendelian randomization (TSMR) analysis to estimate the causality of circulating IL-18 levels on inflammatory and autoimmune diseases. RESULTS: The IVW method results showed evidence of a causal relationship between IL-18 and the risk of systemic lupus erythematosus (SLE) (OR = 1.32; 95% CI 1.15, 1.50; p < .001) and type 1 diabetes (T1D) (OR = 1.22; 95% CI 1.06, 1.42; p = .007) in individuals of European ancestry. No significant heterogeneity or horizontal pleiotropy for SLE and T1D was detected. The sensitivity analysis, which involved removing confounding SNP, produced similar results for SLE and T1D. The results of sensitivity analysis using leave-one-out method indicated no single SNP significantly influenced the analysis results. However, we did not find any significant findings for multiple sclerosis, psoriasis, asthma, and osteoarthritis. CONCLUSIONS: Our analyses suggest that circulating IL-18 is significantly related to SLE and T1D and may serve as a potential target for the treatment of these diseases.


Asunto(s)
Enfermedades Autoinmunes , Diabetes Mellitus Tipo 1 , Lupus Eritematoso Sistémico , Humanos , Diabetes Mellitus Tipo 1/genética , Estudio de Asociación del Genoma Completo , Interleucina-18/genética , Lupus Eritematoso Sistémico/genética
5.
Eur Radiol ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39009880

RESUMEN

OBJECTIVES: To explore the interrelationships between structural and functional changes as well as the potential neurotransmitter profile alterations in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients. METHODS: Structural magnetic resonance imaging (sMRI) and resting-state functional MRI data from 20 drug-naïve BECTS patients and 33 healthy controls (HCs) were acquired. Parallel independent component analysis (P-ICA) was used to identify covarying components among gray matter volume (GMV) maps and fractional amplitude of low-frequency fluctuations (fALFF) maps. Furthermore, we explored the spatial correlations between GMV/fALFF changes derived from P-ICA and neurotransmitter maps in JuSpace toolbox. RESULTS: A significantly positive correlation (p < 0.001) was identified between one structural component (GMV_IC6) and one functional component (fALFF_IC4), which showed significant group differences between drug-naïve BECTS patients and HCs (GMV_IC6: p < 0.01; fALFF_IC4: p < 0.001). GMV_IC6 showed increased GMV in the frontal lobe, temporal lobe, thalamus, and precentral gyrus as well as fALFF_IC4 had enhanced fALFF in the cerebellum in drug-naïve BECTS patients compared to HCs. Moreover, significant correlations between GMV alterations in GMV_IC6 and the serotonin (5HT1a: p < 0.001; 5HT2a: p < 0.001), norepinephrine (NAT: p < 0.001) and glutamate systems (mGluR5: p < 0.001) as well as between fALFF alterations in fALFF_IC4 and the norepinephrine system (NAT: p < 0.001) were detected. CONCLUSION: The current findings suggest co-altered structural/functional components that reflect the correlation of language and motor networks as well as associated with the serotonergic, noradrenergic, and glutamatergic neurotransmitter systems. CLINICAL RELEVANCE STATEMENT: The relationship between anatomical brain structure and intrinsic neural activity was evaluated using a multimodal fusion analysis and neurotransmitters which might provide an important window into the multimodal neural and underlying molecular mechanisms of benign childhood epilepsy with central-temporal spikes. KEY POINTS: Structure-function relationships in drug-naïve benign childhood epilepsy with central-temporal spikes (BECTS) patients were explored. The interrelated structure-function components were found and correlated with the serotonin, norepinephrine, and glutamate systems. Co-altered structural/functional components reflect the correlation of language and motor networks and correlate with the specific neurotransmitter systems.

6.
Neurol Sci ; 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733435

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a debilitating and rapidly fatal neurodegenerative disease, which is characterized by the selective loss of the upper and lower motor neurons. The pathogenesis of ALS remains to be elucidated and has been connected to genetic, environmental and immune conditions. Evidence from clinical and experimental studies has suggested that the immune system played an important role in ALS pathophysiology. Autoantibodies are essential components of the immune system. Several autoantibodies directed at antigens associated with ALS pathogenesis have been identified in the serum and/or cerebrospinal fluid of ALS patients. The aim of this review is to summarize the presence and clinical significance of autoantibodies in ALS.

7.
J Integr Neurosci ; 22(5): 118, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37735122

RESUMEN

Although some progress has been made in tumor treatment, gliomas remain one of the tumors that can still seriously threaten human life and health. Due to the particularity of the immune microenvironment of the central nervous system and the strong invasiveness of tumors, the treatment of gliomas remains a major challenge. Currently, researchers have explored a large number of immunotherapy programs to improve the survival and prognosis of glioma patients, including tumor vaccines, immune checkpoint inhibitors, adoptive cell transfer therapy, viral vector therapy, and genetic engineering therapy. The goal of these programs is to activate or change the immunosuppressive environment and target tumor cells through drugs, combined with surgical resection, radiotherapy, chemotherapy, and anti-angiogenesis drugs, to achieve the purpose of treating glioma. This review briefly describes the immunosuppressive microenvironment of gliomas and summarizes recent immunotherapeutic strategies and their progress. The aim is to summarize the latest immunotherapies for the treatment of gliomas and provide new research directions.


Asunto(s)
Glioma , Inmunoterapia , Humanos , Glioma/terapia , Sistema Nervioso Central , Microambiente Tumoral
8.
J Am Chem Soc ; 144(30): 13556-13564, 2022 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-35867963

RESUMEN

Piperazic acid (Piz) is a nonproteinogenic amino acid possessing a rare nitrogen-nitrogen bond. However, little is known about how Piz is incorporated into nonribosomal peptides, including whether adenylation domains specific to Piz exist. In this study, we show that free piperazic acid is directly adenylated and then incorporated into the incarnatapeptin nonribosomal peptides through isotopic incorporation studies. We also use in vitro reconstitution to demonstrate adenylation of free piperazic acid with a three-domain nonribosomal peptide synthetase from the incarnatapeptin gene cluster. We furthermore use bioinformatics and site-directed mutagenesis to outline consensus sequences for the adenylation of piperazic acid, which can now be used for the prediction of gene clusters linked to piperazic-acid-containing peptides. Finally, we discover a fusion protein of a piperazate synthase and an adenylation domain, highlighting the close biosynthetic relationship of piperazic acid formation and its adenylation. Altogether, our work demonstrates the evolution of biosynthetic systems for the activation of free piperazic acid through adenylation, a pathway we suggest is likely to be employed in the majority of pathways to piperazic-acid-containing peptides.


Asunto(s)
Péptido Sintasas , Piridazinas , Nitrógeno , Péptido Sintasas/metabolismo , Péptidos/química , Piridazinas/química , Especificidad por Sustrato
9.
Bioorg Chem ; 119: 105494, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34836643

RESUMEN

Both HIV and DENV are serious threats to human life, health and social economy today. So far, no vaccine for either HIV or DENV has been developed successfully. The research on anti-HIV or DENV drugs is still of great significance. In this study we developed a series of novel 2-Aryl-1H-pyrazole-S-DABOs with C6-strucutral optimizations as potent NNRTIs, among which, 8 compounds had low cytotoxicity and EC50 values in the range of 0.0508 âˆ¼ 0.0966 µM, and their selectivity index was SI > 1415 âˆ¼ 3940. In particular, two compounds 4a and 4b were identified to have good inhibitory effects on DENV of four serotypes. The EC50 of compound 4a and 4b against DENV-II (13.2 µM and 9.23 µM, respectively) were better than that of the positive control ribavirin (EC50 = 40.78 µM). In addition, the effect of C-6 substituents on the anti-HIV or anti-DENV activity of these compounds was also discussed.


Asunto(s)
Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , VIH-1/efectos de los fármacos , Pirazoles/farmacología , Antivirales/síntesis química , Antivirales/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-Actividad
10.
BMC Ophthalmol ; 22(1): 162, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35395739

RESUMEN

AIM: To study the short-term change of macular function and the correlates after intravitreal conbercept for CRVO-ME. STUDY DESIGN: Prospective, clinical study. METHODS: Twenty Three patients(23 eyes) were recruited, who were non-ischemia central retinal vein occlusion diagnosed by FFA (fundus fluorescein angiography) and treated with intravitreal conbercept for macular edema, best - corrected visual acuity ( BCVA), central macular thickness(CMT), amplitude density of P1 wave and implicit time of P1,N1 wave from ring 1 and ring 2 of mf-ERG were measured before and 1 week、2 month after treatment. RESULTS: Compared to the baseline, BCVA、CMT、amplitude density of P1 wave and implicit time of P1,N1 wave from ring 1 and ring 2 were greatly improved at 1 W、2 M after treatment; better results were gained at 2 M compared to 1 W; Pearson correlation analysis shows no significantly correlation between the improvement of mf-ERG with the change of BCVA、CMT. CONCLUSION: The BCVA、the structure and the function of macular were greatly improved after intravitreal conbercept for central retinal vein occlusion induced macular edema; however no significantly correlation between the improvement of the function of macular with the strcture of macular and BCVA.


Asunto(s)
Edema Macular , Oclusión de la Vena Retiniana , Inhibidores de la Angiogénesis/uso terapéutico , Angiografía con Fluoresceína , Humanos , Inyecciones Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Edema Macular/etiología , Estudios Prospectivos , Proteínas Recombinantes de Fusión , Oclusión de la Vena Retiniana/diagnóstico , Oclusión de la Vena Retiniana/tratamiento farmacológico , Tomografía de Coherencia Óptica/métodos , Resultado del Tratamiento , Agudeza Visual
11.
Nano Lett ; 21(14): 6202-6210, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34259530

RESUMEN

Life is recognized as a sophisticated self-assembling material system. Cancer involves the overexpression and improper self-assembly of proteins, such as cytoskeleton protein vimentin, an emerging target related to tumor metastasis. Herein, we design a binding-induced fibrillogenesis (BIF) peptide that in situ forms fibrous networks, blocking the improper self-assembly of vimentin against cancer. The BIF peptide can bind to vimentin and subsequently perform fibrillogenesis to form fibers on vimentin. The resultant peptide fibrous network blocks vimentin skeletonization and inhibits the migration and invasion of tumor cells. In mouse models of tumor metastasis, the volume of tumor and the number of lung metastases are markedly decreased. Moreover, the efficacy of BIF peptide (5 mg/kg) is much higher than small molecular antimetastasis drug withaferin A (5 mg/kg) as a standard, indicating that the BIF peptide shows advantages over small molecular inhibitors in blocking the intracellular protein self-assembly.


Asunto(s)
Neoplasias de la Mama , Animales , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Movimiento Celular , Femenino , Humanos , Ratones , Péptidos , Vimentina/genética
12.
Yi Chuan ; 44(7): 581-590, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35858770

RESUMEN

MC1R (melanocortin 1 receptor) encodes the melanocortin-1 receptor, which can activate intracellular cAMP synthesis under the stimulation of the α-melanocyte stimulating hormone (α-MSH) ligand. Increased cAMP then activates the protein kinase A (PKA) pathway, resulting in the up-regulation of the expression of the microphthalmia-associated transcription factor (MITF) which is a critical regulatory factor of melanin synthesis, and tyrosinase (TYR), the rate-limiting enzyme of melanin synthesis tyrosinase (TYR), and ultimately affects production of eumelanin and pheomelanin, and the coat color phenotype of mammalian species. Previous reports have indicated that the mutation A243T in the transmembrane domain 6 (TM6) of MC1R protein might disrupt the function of MC1R, contributing to the red phenotype in Duroc pig. However, functional analysis of the A243T mutation in MC1R has not yet been carried out. In this study, we attempted to used single-stranded oligo-deoxyribonucleotides (ssODN) as donor templates to introduce the c.727G>A (A243T) mutation into MC1R in human melanoma cell line SK-MEL-2 by CRISPR/Cas9 to analyze its effects on MC1R functions. We found the occurrence of ssODN recombination reached to 10%. Unfortunately, Sanger sequencing MC1R in six single-cell clones revealed that none carried the c.727G>A mutation, but all carried undesired mutations surrounding the target site. Cells transfected with CRISPR/Cas9 plasmids and ssODN presented significantly attenuated cAMP activation, and down-regulated MITF and TYR expression, indicating that the editing MC1R could affect the melanin synthesis function in cells. This study provides a basis for further investigation the mechanism of MC1R mutation on animal coat color.


Asunto(s)
Melanoma , Receptor de Melanocortina Tipo 1 , Animales , Sistemas CRISPR-Cas , Humanos , Mamíferos/metabolismo , Melaninas/genética , Melanoma/genética , Melanoma/metabolismo , Monofenol Monooxigenasa/metabolismo , Receptor de Melanocortina Tipo 1/genética , Receptor de Melanocortina Tipo 1/metabolismo , Porcinos
13.
Appl Environ Microbiol ; 87(24): e0153421, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34586909

RESUMEN

Biological foaming (or biofoaming) is a frequently occurring problem in wastewater treatment plants (WWTPs) and is attributed to the overwhelming growth of filamentous bulking and foaming bacteria (BFB). Biological foaming has been intensively investigated, with BFB like Microthrix and Skermania having been identified from WWTPs and implicated in foaming. Nevertheless, studies are still needed to improve our understanding of the microbial diversity of WWTP biofoams and how microbial activities contribute to foaming. In this study, sludge foaming at the Qinghe WWTP of China was monitored, and sludge foams were investigated using culture-dependent and culture-independent microbiological methods. The foam microbiomes exhibited high abundances of Skermania, Mycobacterium, Flavobacteriales, and Kaistella. A previously unknown bacterium, Candidatus Kaistella beijingensis, was cultivated from foams, its genome was sequenced, and it was phenotypically characterized. Ca. K. beijingensis exhibits hydrophobic cell surfaces, produces extracellular polymeric substances (EPS), and metabolizes lipids. Ca. K. beijingensis abundances were proportional to EPS levels in foams. Several proteins encoded by the Ca. K. beijingensis genome were identified from EPS that was extracted from sludge foams. Ca. K. beijingensis populations accounted for 4 to 6% of the total bacterial populations in sludge foam samples within the Qinghe WWTP, although their abundances were higher in spring than in other seasons. Cooccurrence analysis indicated that Ca. K. beijingensis was not a core node among the WWTP community network, but its abundances were negatively correlated with those of the well-studied BFB Skermania piniformis among cross-season Qinghe WWTP communities. IMPORTANCE Biological foaming, also known as scumming, is a sludge separation problem that has become the subject of major concern for long-term stable activated sludge operation in decades. Biological foaming was considered induced by foaming bacteria. However, the occurrence and deterioration of foaming in many WWTPs are still not completely understood. Cultivation and characterization of the enriched bacteria in foaming are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the understanding of their relationships with foaming and performance of WWTPs.


Asunto(s)
Flavobacteriaceae , Aguas del Alcantarillado , Purificación del Agua , China , Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Filogenia , Aguas del Alcantarillado/microbiología
14.
Chemphyschem ; 22(12): 1193-1200, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-33969587

RESUMEN

Solar energy can be stored via either an indirect route in which electricity is involved as an intermediate step, or a direct route that utilizes photogenerated charge carriers for direct solar energy conversion. In this study, we investigate the fundamental difference between the direct and indirect routes in solar energy conversion using a new photoelectrochemical energy storage cell (PESC) as a model device. This PESC centers on a liquid junction that utilizes CH3 NH3 PbI3 perovskite to drive photoelectrochemical reactions of Benzoquinone (BQ) and Ferrocene (Fc) redox species. The experimental studies show that the equilibrium redox potentials are 0.1 V and -0.78 V (vs Ag/AgNO3 ) for Fc+ /Fc and BQ/BQ.- , respectively, which would produce a theoretical open-circuit voltage of 0.88 V for the storage device. The physics-based computational analysis shows a relatively flat reaction rate distribution in the electrode for the indirect route; however, in the direct route the photoelectrochemical reaction rate is critically affected by electron concentration due to strong light absorption of the perovskite material, which has been shown to vary by at least 10-fold in the transverse direction across the photoelectrode. The drastic variation of reaction rate in the photoelectrode creates an electric field that is 7.5 times stronger than the bulk electrolyte, which causes the photo-converted reaction product (i. e., BQ.- ) to drift away from the photoelectrode thereby creating a constant reaction driving force. As a result, it has been shown that the intrinsic solar to chemical conversion (ISTC) efficiency improves by ∼40 % for the direct route compared to the indirect route at 0.05 mA/cm2 .

15.
Rapid Commun Mass Spectrom ; 35(23): e9198, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34559434

RESUMEN

RATIONALE: Resolution and sensitivity are two key parameters for describing the performance of high-field asymmetric waveform ion mobility spectrometry (FAIMS). An increase in the resolving power of FAIMS has been realized by adding helium to nitrogen in planar FAIMS, but it comes at the expense of sensitivity. METHODS: Here, a new hollow needle-to-ring discharge device integrated on a PCB substrate is used as the ion source for FAIMS. Helium flows from the hollow part of the hollow needle to improve the ionization effect. Nitrogen carries the sample into the ionization chamber and is mixed with helium as the carrier gas. RESULTS: Under a nitrogen flow rate of 1 L min-1 , 1.5 L min-1 , 2 L min-1 , and 2.5 L min-1 , adding helium at different flow rates (0.2 L min-1 , 0.3 L min-1 , 0.5 L min-1 , and 1 L min-1 ) can simultaneously improve the separation ability and sensitivity. Helium and nitrogen with flow rates of 0.2, 0.3, 0.5, and 1 L min-1 were added to nitrogen (2 L min-1 ). The separation ability and sensitivity of the mixed gases doped with helium are better than those of nitrogen. The larger the RF voltage amplitude is, the more obvious the improvement in the separation ability when helium is added. However, helium doping has the opposite effect on the sensitivity. CONCLUSIONS: This study provides a new idea and technical means for the application of helium and nitrogen gas mixtures in planar FAIMS. This method can greatly improve the performance of FAIMS.

16.
Phys Chem Chem Phys ; 23(5): 3407-3416, 2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33506826

RESUMEN

The ferroelectric field-effect transistors (FeFETs) based on graphene/ferroelectric (Gr/FE) hybrid systems have been attracting a lot of attention in recent years. The interface interaction and charge transfer between graphene and the ferroelectric substrates are important factors that determine the performance of graphene-based FeFETs. According to our intuitive sense, the electrostatically doped carriers in graphene on the ferroelectric positive and negative surfaces should be n-type and p-type, respectively. In the present work, however, by employing first-principles density functional theory (DFT) calculations, we reveal that an unusual charge doping effect occurs in graphene on the thermodynamically preferred ferroelectric BiAlO3(0001) polar surfaces. The graphene on the BiAlO3(0001) positive surface is electrostatically doped p-type, while the BiAlO3(0001) negative surface induces n-type carriers in the graphene overlayer. Further analysis demonstrates that, although the electrostatic doping effect in the Gr/FE system depends on the polarization direction of the ferroelectric substrate, the resultant carrier type and density in graphene are determined by the specific band arrangement between graphene and the ferroelectric polar surface. In addition to the graphene-based FeFETs, our results predict that the Gr/BiAlO3(0001) systems can be used to fabricate graphene p-n homojunctions by engineering the domain pattern in the ferroelectric substrate.

17.
Neurol Sci ; 42(6): 2353-2361, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33044668

RESUMEN

OBJECTIVE: Exploring the role of amygdala enlargement (AE) in temporal lobe epilepsy (TLE) without ipsilateral mesial temporal sclerosis (MTS) using comprehensive presurgical workup tools including traditional tools, automatically volumetric analysis, high-density EEG (HD-EEG) source imaging (HD-ESI), and stereoelectroencephalography (SEEG). METHODS: Nine patients diagnosed with TLE-AE who underwent resective surgeries encompassing the amygdala were retrospectively studied. HD-ESI was obtained using 256-channel HD-EEG on the individualized head model. For automatic volumetric analysis, 48 matched controls were enrolled. Diagnosis and surgical strategies were based on a comprehensive workup following the anatomo-electro-clinical principle. RESULTS: At post-operative follow-up (average 30.9 months), eight patients had achieved Engel class I and one Engel class II recovery. HD-ESI yielded unifocal source estimates in anterior mesial temporal region in 85.7% of cases. Automatic volumetric analysis showed the AE sides were consistent with the values determined through other preoperative workup tools. Furthermore, the amygdala volume of the affected sides in AE was significantly greater than that of the larger sides in controls (p < 0.001). Meanwhile, the amygdala volume lateral index (LI) of AE was significantly higher than in controls (p < 0.001). SEEG analysis showed that ictal onsets arose from the enlarged amygdala (and hippocampus) in all cases. CONCLUSION: In addition to traditional workup tools, automatic volumetric analysis, HD-ESI on individualized head model, and invasive SEEG can provide evidence of epileptogenicity in TLE-AE. Resective surgical strategies encompassing the amygdala result in better prognosis. In suspected TLE cases, more attention should be focused on detecting enlargement of amygdala which sometimes is "hidden" in "MR-negative" non-MTS cases.


Asunto(s)
Epilepsia del Lóbulo Temporal , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/cirugía , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Hipocampo , Humanos , Imagen por Resonancia Magnética , Estudios Retrospectivos , Lóbulo Temporal
18.
Med Sci Monit ; 27: e928800, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33622998

RESUMEN

BACKGROUND Hepatocellular carcinoma (HCC) causes a heavy disease burden worldwide. Cell division cycle 45 (Cdc45) and its encoding gene (CDC45) have been studied for a long time, but their expression patterns and roles in liver carcinogenesis and advanced HCC deterioration are still incompletely understood. This study integrated tissue microarray and bioinformatics analyses to explore the expression and clinical value of CDC45 and Cdc45 in HCC. MATERIAL AND METHODS In HCC, the expression and relationships with clinic-pathological parameters of CDC45 and Cdc45 were investigated by integrating the RNA-sequencing data, downloaded from The Cancer Genome Atlas and Oncomine databases, and tissue microarray with immunohistochemistry staining. Co-expressed genes and genetic alterations of CDC45 separately obtained from Oncomine and cBioPortal databases were identified to shed light on the potential mechanisms of CDC45 in HCC. RESULTS CDC45 and Cdc45 were both overexpressed in HCC tissues, and the CDC45 level progressively increased from stage I to III. The survival outcomes of the group with high CDC45 expression were significantly worse compared with the group with low expression. Amplification and deep deletion were 2 major significant alteration types in HCC patients, and the outcomes were worse in patients with altered versus unaltered CDC45. NUDT1, E2F1, CCNE2, MCM5, and CENPM were identified as the most significantly co-expressed genes. CONCLUSIONS CDC45 and Cdc45 were both upregulated in HCC, and increased expression levels and genetic alternations of CDC45 were correlated with worse prognosis in HCC patients. CDC45 may promote HCC by co-expressing with NUDT1, E2F1, CCNE2, MCM5, and CENPM.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Biomarcadores de Tumor/genética , Proteínas de Ciclo Celular/metabolismo , Biología Computacional/métodos , Expresión Génica , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Pronóstico , Análisis de Secuencia de ARN , Transcriptoma
19.
Zhonghua Nan Ke Xue ; 27(9): 787-792, 2021 Sep.
Artículo en Zh | MEDLINE | ID: mdl-34914253

RESUMEN

OBJECTIVE: To evaluate the safety and clinical efficiency of holmium laser enucleation of the prostate (HoLEP) in the treatment of small-volume BPH (SBPH) complicated by severe lower urinary tract symptoms (LUTS). METHODS: We retrospectively analyzed the clinical data on 82 cases of SBPH with severe LUTS treated by HoLEP from January 2017 to December 2018. The patients were aged (65.5 ± 7.6) years, with a mean prostate volume of <40 ml, a total IPSS of 24.8 ± 4.6, a QOL score of 5.2 ± 0.8, the maximum urinary flow rate (Qmax) of (7.6 ± 3.7) ml/s, and a mean PSA level of (1.8 ± 1.4) µg/L. RESULTS: All the operations were successfully completed, the mean operation time averaging (30.2 ± 5.0) min, enucleation time (26.7 ± 5.6) min and comminution time (3.5 ± 1.1) min, and the enucleated tissue weighing (20.3 ± 4.9) g. After surgery, the bladders were irrigated for (3.5 ± 1.9) h, with (3.0 ± 1.7) L of rinse solution, and catheterization lasted (24.8 ± 9.7) h. Histopathology revealed moderate or severe lymphocytic infiltration in 69 cases (84.1%). At 6 months after operation, significant improvement was observed in the IPSS, QOL, Qmax and PSA level compared with the baseline (P < 0.05). To date, no urethral stricture-related reoperation was ever necessitated. CONCLUSIONS: HoLEP is safe and effective for the treatment of SBPH complicated by severe LUTS and can be employed after adequate preoperative evaluation of the patient.《.


Asunto(s)
Láseres de Estado Sólido , Síntomas del Sistema Urinario Inferior , Hiperplasia Prostática , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Síntomas del Sistema Urinario Inferior/cirugía , Masculino , Próstata/cirugía , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/cirugía , Calidad de Vida , Estudios Retrospectivos
20.
J Integr Neurosci ; 19(3): 513-519, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33070532

RESUMEN

"Tianma" (Gastrodia) and "gouteng" (Uncaria) are both widely used to treat cerebral ischemia. At the same time, "ezhu" (Curcuma longa) or turmeric, is derived from the dried roots of C. longa. It is a polyphenol known for its anti-inflammatory effects and its promotion of blood vessel endothelial function. This study explored the neuroprotective effects of a water extract of "tianma", "gouteng", and "ezhu" against ischemic injury. Flow cytometry analysis showed that Gastrodia, Uncaria, and Curcuma reduced the proportion of apoptotic cells in CoCl2 induced B35 (P = 0.0027) and SH-SY5Y (P = 0.0006) cell sample relative to the respective control group. Western blot indicated that Gastrodia, Uncaria, and Curcuma upregulated the expression of Bcl-2 and inversely downregulated Bax and Caspase-3 (P < 0.001). The infarct volume observed in the Gastrodia, Uncaria, and Curcuma group was also decreased compared with the control group (P < 0.05). Immunofluorescence detection revealed a lower expression of Caspase-7 in the Gastrodia, Uncaria, and Curcuma group than in the control group, while expression was negligible in the sham group. Gastrodia, Uncaria, and Curcuma confer neuroprotective effects in CoCl2 induced B35/SH-SY5Y cells and a rat model of ischemia by way of its anti-apoptotic effects.


Asunto(s)
Isquemia Encefálica/prevención & control , Medicamentos Herbarios Chinos/administración & dosificación , Gastrodia , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Extractos Vegetales/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Curcuma , Humanos , Ratas
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