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1.
Cell ; 157(7): 1605-18, 2014 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-24949972

RESUMEN

Translational readthrough, observed primarily in less complex organisms from viruses to Drosophila, expands the proteome by translating select transcripts beyond the canonical stop codon. Here, we show that vascular endothelial growth factor A (VEGFA) mRNA in mammalian endothelial cells undergoes programmed translational readthrough (PTR) generating VEGF-Ax, an isoform containing a unique 22-amino-acid C terminus extension. A cis-acting element in the VEGFA 3' UTR serves a dual function, not only encoding the appended peptide but also directing the PTR by decoding the UGA stop codon as serine. Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 binds this element and promotes readthrough. Remarkably, VEGF-Ax exhibits antiangiogenic activity in contrast to the proangiogenic activity of VEGF-A. Pathophysiological significance of VEGF-Ax is indicated by robust expression in multiple human tissues but depletion in colon adenocarcinoma. Furthermore, genome-wide analysis revealed AGO1 and MTCH2 as authentic readthrough targets. Overall, our studies reveal a novel protein-regulated PTR event in a vertebrate system.


Asunto(s)
Células Endoteliales/metabolismo , Biosíntesis de Proteínas , Factor A de Crecimiento Endotelial Vascular/genética , Regiones no Traducidas 3' , Secuencia de Aminoácidos , Animales , Aorta/citología , Secuencia de Bases , Bovinos , Línea Celular , Codón de Terminación , Células HEK293 , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Humanos , Ratones , Datos de Secuencia Molecular , Isoformas de Proteínas/genética , Alineación de Secuencia
2.
Proc Natl Acad Sci U S A ; 120(16): e2217665120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37036971

RESUMEN

The mitochondrial calcium uniporter is a Ca2+ channel that imports cytoplasmic Ca2+ into the mitochondrial matrix to regulate cell bioenergetics, intracellular Ca2+ signaling, and apoptosis. The uniporter contains the pore-forming MCU subunit, an auxiliary EMRE protein, and the regulatory MICU1/MICU2 subunits. Structural and biochemical studies have suggested that MICU1 gates MCU by blocking/unblocking the pore. However, mitoplast patch-clamp experiments argue that MICU1 does not block, but instead potentiates MCU via allosteric mechanisms. Here, we address this direct clash of the proposed MICU1 function. Supporting the MICU1-occlusion mechanism, patch-clamp demonstrates that purified MICU1 strongly suppresses MCU Ca2+ currents, and this inhibition is abolished by mutating the MCU-interacting K126 residue. Moreover, a membrane-depolarization assay shows that MICU1 prevents MCU-mediated Na+ flux into intact mitochondria under Ca2+-free conditions. Examining the observations underlying the potentiation model, we found that MICU1 occlusion was not detected in mitoplasts not because MICU1 cannot block, but because MICU1 dissociates from the uniporter complex. Furthermore, MICU1 depletion reduces uniporter transport not because MICU1 can potentiate MCU, but because EMRE is down-regulated. These results firmly establish the molecular mechanisms underlying the physiologically crucial process of uniporter regulation by MICU1.


Asunto(s)
Calcio , Proteínas de Transporte de Membrana Mitocondrial , Calcio/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Canales de Calcio/metabolismo , Membranas Mitocondriales/metabolismo , Calcio de la Dieta , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo
3.
J Virol ; 98(4): e0177323, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38530012

RESUMEN

Dengue vaccine candidates have been shown to improve vaccine safety and efficacy by altering the residues or accessibility of the fusion loop on the virus envelope protein domain II (DIIFL) in an ex vivo animal study. The current study aimed to comprehensively investigate the impact of DIIFL mutations on the antigenicity, immunogenicity, and protective efficacy of Japanese encephalitis virus (JEV) virus-like particles (VLPs) in mice. We found the DIIFL G106K/L107D (KD) and W101G/G106K/L107D (GKD) mutations altered the binding activity of JEV VLP to cross-reactive monoclonal antibodies but had no effect on their ability to elicit total IgG antibodies in mice. However, JEV VLPs with KD or GKD mutations induced significantly less neutralizing antibodies against JEV. Only 46% and 31% of the KD and GKD VLPs-immunized mice survived compared to 100% of the wild-type (WT) VLP-immunized mice after a lethal JEV challenge. In passive protection experiments, naïve mice that received sera from WT VLP-immunized mice exhibited a significantly higher survival rate of 46.7% compared to those receiving sera from KD VLP- and GKD VLP-immunized mice (6.7% and 0%, respectively). This study demonstrated that JEV DIIFL is crucial for eliciting potently neutralizing antibodies and protective immunity against JEV. IMPORTANCE: Introduction of mutations into the fusion loop is one potential strategy for generating safe dengue and Zika vaccines by reducing the risk of severe dengue following subsequent infections, and for constructing live-attenuated vaccine candidates against newly emerging Japanese encephalitis virus (JEV) or Japanese encephalitis (JE) serocomplex virus. The monoclonal antibody studies indicated the fusion loop of JE serocomplex viruses primarily comprised non-neutralizing epitopes. However, the present study demonstrates that the JEV fusion loop plays a critical role in eliciting protective immunity in mice. Modifications to the fusion loop of JE serocomplex viruses might negatively affect vaccine efficacy compared to dengue and zika serocomplex viruses. Further studies are required to assess the impact of mutant fusion loop encoded by commonly used JEV vaccine strains on vaccine efficacy or safety after subsequent dengue virus infection.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Vacunas contra la Encefalitis Japonesa , Animales , Ratones , Aminoácidos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Dengue , Virus de la Encefalitis Japonesa (Especie)/fisiología , Encefalitis Japonesa/inmunología , Encefalitis Japonesa/prevención & control , Epítopos , Vacunas contra la Encefalitis Japonesa/genética , Proteínas del Envoltorio Viral/genética , Virus Zika , Infección por el Virus Zika
4.
Bioinformatics ; 40(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38924517

RESUMEN

MOTIVATION: The annotation of cell types from single-cell transcriptomics is essential for understanding the biological identity and functionality of cellular populations. Although manual annotation remains the gold standard, the advent of automatic pipelines has become crucial for scalable, unbiased, and cost-effective annotations. Nonetheless, the effectiveness of these automatic methods, particularly those employing deep learning, significantly depends on the architecture of the classifier and the quality and diversity of the training datasets. RESULTS: To address these limitations, we present a Pruning-enabled Gene-Cell Net (PredGCN) incorporating a Coupled Gene-Cell Net (CGCN) to enable representation learning and information storage. PredGCN integrates a Gene Splicing Net (GSN) and a Cell Stratification Net (CSN), employing a pruning operation (PrO) to dynamically tackle the complexity of heterogeneous cell identification. Among them, GSN leverages multiple statistical and hypothesis-driven feature extraction methods to selectively assemble genes with specificity for scRNA-seq data while CSN unifies elements based on diverse region demarcation principles, exploiting the representations from GSN and precise identification from different regional homogeneity perspectives. Furthermore, we develop a multi-objective Pareto pruning operation (Pareto PrO) to expand the dynamic capabilities of CGCN, optimizing the sub-network structure for accurate cell type annotation. Multiple comparison experiments on real scRNA-seq datasets from various species have demonstrated that PredGCN surpasses existing state-of-the-art methods, including its scalability to cross-species datasets. Moreover, PredGCN can uncover unknown cell types and provide functional genomic analysis by quantifying the influence of genes on cell clusters, bringing new insights into cell type identification and characterizing scRNA-seq data from different perspectives. AVAILABILITY AND IMPLEMENTATION: The source code is available at https://github.com/IrisQi7/PredGCN and test data is available at https://figshare.com/articles/dataset/PredGCN/25251163.


Asunto(s)
Análisis de la Célula Individual , Transcriptoma , Análisis de la Célula Individual/métodos , Transcriptoma/genética , Programas Informáticos , Anotación de Secuencia Molecular/métodos , Animales , Humanos , Perfilación de la Expresión Génica/métodos , Biología Computacional/métodos , Algoritmos
5.
FASEB J ; 38(1): e23397, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38149908

RESUMEN

Toxoplasma gondii relies heavily on the de novo pyrimidine biosynthesis pathway for fueling the high uridine-5'-monophosphate (UMP) demand during parasite growth. The third step of de novo pyrimidine biosynthesis is catalyzed by dihydroorotase (DHO), a metalloenzyme that catalyzes the reversible condensation of carbamoyl aspartate to dihydroorotate. Here, functional analyses of TgDHO reveal that tachyzoites lacking DHO are impaired in overall growth due to decreased levels of UMP, and the noticeably growth restriction could be partially rescued after supplementation with uracil or high concentrations of L-dihydroorotate in vitro. When pyrimidine salvage pathway is disrupted, both DHOH35A and DHOD284E mutant strains proliferated much slower than DHO-expressing parasites, suggesting an essential role of both TgDHO His35 and Asp284 residues in parasite growth. Additionally, DHO deletion causes the limitation of bradyzoite growth under the condition of uracil supplementation or uracil deprivation. During the infection in mice, the DHO-deficient parasites are avirulent, despite the generation of smaller tissue cysts. The results reveal that TgDHO contributes to parasite growth both in vitro and in vivo. The significantly differences between TgDHO and mammalian DHO reflect that DHO can be exploited to produce specific inhibitors targeting apicomplexan parasites. Moreover, potential DHO inhibitors exert beneficial effects on enzymatic activity of TgDHO and T. gondii growth in vitro. In conclusion, these data highlight the important role of TgDHO in parasite growth and reveal that it is a promising anti-parasitic target for future control of toxoplasmosis.


Asunto(s)
Parásitos , Toxoplasma , Animales , Ratones , Dihidroorotasa , Pirimidinas/farmacología , Uracilo , Uridina Monofosfato , Mamíferos
6.
Proc Natl Acad Sci U S A ; 119(29): e2206462119, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858305

RESUMEN

Emulsification is a crucial technique for mixing immiscible liquids into droplets in numerous areas ranging from food to medicine to chemical synthesis. Commercial emulsification methods are promising for high production, but suffer from high energy input. Here, we report a very simple and scalable emulsification method that employs the drag-reducing liquid gating structure to create a smooth liquid-liquid interface for the reduction of resistance and tunable generation of droplets with good uniformity. Theoretical modeling and experimental results demonstrate that our method exhibits ultrahigh efficiency, which can reach up to more than 4 orders of magnitude greater energy-saving compared to commercial methods. For temperature-sensitive biological components, such as enzymes, proteins, and bacteria, it can offer a comfortable environment to avoid exposure to high temperatures during emulsifying, and the interface also enables the suppression of fouling. This unique drag-reducing liquid gating interfacial emulsification mechanism promotes the efficiency of droplet generation and provides fresh insight into the innovation of emulsifications that can be applied in many fields, including the food industry, the daily chemical industry, biomedicine, material fabrication, the petrochemical industry, and beyond.

7.
Int J Cancer ; 155(1): 27-39, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38430541

RESUMEN

Information about the NMR metabolomics landscape of overall, and common cancers is still limited. Based on a cohort of 83,290 participants from the UK Biobank, we used multivariate Cox regression to assess the associations between each of the 168 metabolites with the risks of overall cancer and 20 specific types of cancer. Then, we applied LASSO to identify important metabolites for overall cancer risk and obtained their associations using multivariate cox regression. We further conducted mediation analysis to evaluate the mediated role of metabolites in the effects of traditional factors on overall cancer risk. Finally, we included the 13 identified metabolites as predictors in prediction models, and compared the accuracies of our traditional models. We found that there were commonalities among the metabolic profiles of overall and specific types of cancer: the top 20 frequently identified metabolites for 20 specific types of cancer were all associated with overall cancer; most of the specific types of cancer had common identified metabolites. Meanwhile, the associations between the same metabolite with different types of cancer can vary based on the site of origin. We identified 13 metabolic biomarkers associated with overall cancer, and found that they mediated the effects of traditional factors. The accuracies of prediction models improved when we added 13 identified metabolites in models. This study is helpful to understand the metabolic mechanisms of overall and a wide range of cancers, and our results also indicate that NMR metabolites are potential biomarkers in cancer diagnosis and prevention.


Asunto(s)
Metabolómica , Neoplasias , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Metaboloma , Metabolómica/métodos , Neoplasias/epidemiología , Neoplasias/metabolismo , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Biobanco del Reino Unido , Reino Unido/epidemiología
8.
Angiogenesis ; 27(3): 333-349, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38580870

RESUMEN

Sustained angiogenesis stands as a hallmark of cancer. The intricate vascular tumor microenvironment fuels cancer progression and metastasis, fosters therapy resistance, and facilitates immune evasion. Therapeutic strategies targeting tumor vasculature have emerged as transformative for cancer treatment, encompassing anti-angiogenesis, vessel normalization, and endothelial reprogramming. Growing evidence suggests the dynamic regulation of tumor angiogenesis by infiltrating myeloid cells, such as macrophages, myeloid-derived suppressor cells (MDSCs), and neutrophils. Understanding these regulatory mechanisms is pivotal in paving the way for successful vasculature-targeted cancer treatments. Therapeutic interventions aimed to disrupt myeloid cell-mediated tumor angiogenesis may reshape tumor microenvironment and overcome tumor resistance to radio/chemotherapy and immunotherapy.


Asunto(s)
Células Mieloides , Neoplasias , Neovascularización Patológica , Microambiente Tumoral , Humanos , Neoplasias/irrigación sanguínea , Neoplasias/patología , Neoplasias/terapia , Neoplasias/inmunología , Neovascularización Patológica/patología , Animales , Células Mieloides/patología , Células Mieloides/metabolismo , Células Supresoras de Origen Mieloide/metabolismo , Células Supresoras de Origen Mieloide/inmunología , Angiogénesis
9.
BMC Med ; 22(1): 161, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38616254

RESUMEN

BACKGROUND: To study the shared genetic structure between autoimmune diseases and B-cell acute lymphoblastic leukemia (B-ALL) and identify the shared risk loci and genes and genetic mechanisms involved. METHODS: Based on large-scale genome-wide association study (GWAS) summary-level data sets, we observed genetic overlaps between autoimmune diseases and B-ALL, and cross-trait pleiotropic analysis was performed to detect shared pleiotropic loci and genes. A series of functional annotation and tissue-specific analysis were performed to determine the influence of pleiotropic genes. The heritability enrichment analysis was used to detect crucial immune cells and tissues. Finally, bidirectional Mendelian randomization (MR) methods were utilized to investigate the casual associations. RESULTS: Our research highlighted shared genetic mechanisms between seven autoimmune disorders and B-ALL. A total of 73 pleiotropic loci were identified at the genome-wide significance level (P < 5 × 10-8), 16 of which had strong evidence of colocalization. We demonstrated that several loci have been previously reported (e.g., 17q21) and discovered some novel loci (e.g., 10p12, 5p13). Further gene-level identified 194 unique pleiotropic genes, for example IKZF1, GATA3, IKZF3, GSDMB, and ORMDL3. Pathway analysis determined the key role of cellular response to cytokine stimulus, B cell activation, and JAK-STAT signaling pathways. SNP-level and gene-level tissue enrichment suggested that crucial role pleiotropic mechanisms involved in the spleen, whole blood, and EBV-transformed lymphocytes. Also, hyprcoloc and stratified LD score regression analyses revealed that B cells at different developmental stages may be involved in mechanisms shared between two different diseases. Finally, two-sample MR analysis determined causal effects of asthma and rheumatoid arthritis on B-ALL. CONCLUSIONS: Our research proved shared genetic architecture between autoimmune disorders and B-ALL and shed light on the potential mechanism that might involve in.


Asunto(s)
Artritis Reumatoide , Asma , Enfermedades Autoinmunes , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Estudio de Asociación del Genoma Completo , Enfermedades Autoinmunes/genética
10.
Small ; 20(32): e2401226, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38511543

RESUMEN

Electroredox of organics provides a promising and green approach to producing value-added chemicals. However, it remains a grand challenge to achieve high selectivity of desired products simultaneously at two electrodes, especially for non-isoelectronic transfer reactions. Here a porous heterostructure of Mo2C@Co-NC is successfully fabricated, where subnanometre ß-Mo2C clusters (<1 nm, ≈10 wt%) are confined inside porous Co, N-doped carbon using metalorganic frameworks. It is found that Co species not only promote the formation of ß-Mo2C but also can prevent it from oxidation by constructing the heterojunctions. As noted, the heterostructure achieves >96% yield and 92% Faradaic efficiency (FE) for aldehydes in anodic alcohol oxidation, as well as >99.9% yield and 96% FE for amines in cathodal nitrocompounds reduction in 1.0 M KOH. Precise control of the reaction kinetics of two half-reactions by the electronic interaction between ß-Mo2C and Co is a crucial adjective. Density functional theory (DFT) gives in-depth mechanistic insight into the high aldehyde selectivity. The work guides authors to reveal the electrooxidation nature of Mo2C at a subnanometer level. It is anticipated that the strategy will provide new insights into the design of highly effective bifunctional electrocatalysts for the coproduction of more complex fine chemicals.

11.
BMC Cancer ; 24(1): 774, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937672

RESUMEN

BACKGROUND: Although it is thought that prostatitis or benign prostatic hyperplasia (BPH) is related to prostate cancer (PCa), the underlying causal effects of these diseases are unclear. METHODS: We assessed the causal relationship between prostatitis or BPH and PCa using a two-sample Mendelian randomization (MR) approach. The data utilized in this study were sourced from genome-wide association study. The association of genetic variants from cohorts of prostatitis or BPH and PCa patients was determined using inverse-variance weighted and MR Egger regression techniques. The direction of chance was determined using independent genetic variants with genome-wide significance (P < 5 × 10-6). The accuracy of the results was confirmed using sensitivity analyses. RESULTS: MR analysis showed that BPH had a significant causal effect on PCa (Odds Ratio = 1.209, 95% Confidence Interval: 0.098-0.281, P = 5.079 × 10- 5) while prostatitis had no significant causal effect on PCa (P > 0.05). Additionally, the pleiotropic test and leave-one-out analysis showed the two-sample MR analyses were valid and reliable. CONCLUSIONS: This MR study supports that BPH has a positive causal effect on PCa, while genetically predicted prostatitis has no causal effect on PCa. Nonetheless, further studies should explore the underlying biochemical mechanism and potential therapeutic targets for the prevention of these diseases.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Hiperplasia Prostática , Neoplasias de la Próstata , Prostatitis , Humanos , Masculino , Neoplasias de la Próstata/genética , Hiperplasia Prostática/genética , Prostatitis/genética , Prostatitis/complicaciones , Polimorfismo de Nucleótido Simple , Predisposición Genética a la Enfermedad
12.
BMC Cancer ; 24(1): 458, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609917

RESUMEN

BACKGROUND: The identification of survival predictors is crucial for early intervention to improve outcome in acute myeloid leukemia (AML). This study aim to identify chest computed tomography (CT)-derived features to predict prognosis for acute myeloid leukemia (AML). METHODS: 952 patients with pathologically-confirmed AML were retrospectively enrolled between 2010 and 2020. CT-derived features (including body composition and subcutaneous fat features), were obtained from the initial chest CT images and were used to build models to predict the prognosis. A CT-derived MSF nomogram was constructed using multivariate Cox regression incorporating CT-based features. The performance of the prediction models was assessed with discrimination, calibration, decision curves and improvements. RESULTS: Three CT-derived features, including myosarcopenia, spleen_CTV, and SF_CTV (MSF) were identified as the independent predictors for prognosis in AML (P < 0.01). A CT-MSF nomogram showed a performance with AUCs of 0.717, 0.794, 0.796 and 0.792 for predicting the 1-, 2-, 3-, and 5-year overall survival (OS) probabilities in the validation cohort, which were significantly higher than the ELN risk model. Moreover, a new MSN stratification system (MSF nomogram plus ELN risk model) could stratify patients into new high, intermediate and low risk group. Patients with high MSN risk may benefit from intensive treatment (P = 0.0011). CONCLUSIONS: In summary, the chest CT-MSF nomogram, integrating myosarcopenia, spleen_CTV, and SF_CTV features, could be used to predict prognosis of AML.


Asunto(s)
Leucemia Mieloide Aguda , Nomogramas , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Área Bajo la Curva , Leucemia Mieloide Aguda/diagnóstico por imagen
13.
Langmuir ; 40(31): 16400-16418, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39049446

RESUMEN

This study describes the preparation of Ni-P-Cr3C2 composite coatings using pulsed electrodeposition, with varying Cr3C2 concentrations (0, 1, 2, 3, 4, and 5 g/L). Subsequently, the Ni-P-Cr3C2 composite coatings are heat-treated at different temperatures (200, 400, and 600 °C) using the characteristic of Cr3C2 oxidizing to Cr2O3 at high temperatures. The Ni-P coatings, Ni-P-Cr3C2 composite coatings, and heat-treated-state Ni-P-Cr3C2 composite coatings are compared and discussed. The results show that the hardness, wear resistance, and corrosion resistance of the composite coatings are optimized when the Cr3C2 content is 3 g/L and the heat-treatment temperature is 400 °C. This is due to the presence of oxides such as Cr2O3 on the surface of the composite coatings after heat treatment at 400 °C. By efficiently enhancing the coating's densification to the substrate, these oxides raise the composite coating's resistance to corrosion and wear. The Ni-P-Cr3C2 composite coating in its heat-treated makeup at 400 °C is found to have long-term corrosion resistance in the 3.5 wt % NaCl solution immersion test. This study provides a new idea in the field of corrosion.

14.
Rapid Commun Mass Spectrom ; 38(4): e9688, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38212651

RESUMEN

RATIONALE: Phenylethylamines are one of the most common types of new psychoactive substances, following synthetic cannabinoids and synthetic cathinones. They are regulated in many countries because of their strong hallucinogenic effects, which can cause serious nerve damage. There is a wide variety of phenylethylamines, exhibiting rapid renewal and extremely similar structures, therefore accurate qualitative analysis of isomers is a difficult problem in current drug analysis. METHODS: The dissociation pathways of the position isomers 2-(2-methylaminoprolyl)benzofuran (2-MAPB) and 5-(2-methylaminopropyl)benzofuran (5-MAPB) were investigated by gas chromatography-mass spectrometry and liquid chromatography coupled to high-resolution quadrupole Orbitrap MS. The dissociation patterns of the phenethylamine-based designer drugs 2-MAPB and 5-MAPB were explored and extended in this work based on MS combined with density functional theory studies. RESULTS: For electron ionization mass spectrometry (EI-MS) analysis, the dissociation patterns of 2-MAPB were similar to those of 5-MAPB. For electrospray ionization mass spectrometry (ESI-MSn ) analysis, the hydrogen atom on amino group was facile to form a intramolecular hydrogen bond with the oxygen atom on the parent nucleus of benzofuran in the structure of 2-MAPB, leading to higher abundance of the product ion at m/z 58. However, there was a conjugated system between the positive charge formed by the cleavage of the 5-MAPB side chain and the benzofuran ring, enabling the 5-MAPB to generate a product ion at m/z 131. Computational study showed that energy barrier and spin density difference distribution jointly control the selective dissociation in EI-MS, while different types of orbital interaction induced by intramolecular hydrogen bond led to different dissociation results in ESI-MSn . CONCLUSIONS: These different dissociation patterns could be used to distinguish 2-MAPB from 5-MAPB. This could assist forensic laboratories in the differentiation and characterization of potential isomers in these kinds of compounds, especially in mixtures.

15.
J Am Acad Dermatol ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38878041

RESUMEN

BACKGROUND: Dupilumab effectively treats atopic dermatitis (AD); however, its role in halting the atopic march remains uncertain. OBJECTIVE: To investigate dupilumab's effect on atopic march in pediatric AD patients versus conventional immunomodulators. METHODS: This retrospective cohort study utilized data from the TriNetX US Collaborative Network (2011-2024). Pediatric AD patients (≤18 years) were categorized into DUPI-cohort (newly prescribed dupilumab) or CONV-cohort (prescribed conventional immunomodulators without dupilumab). After 1:1 propensity-score matching, we analyzed atopic march progression, defined by the incident asthma or allergic rhinitis (AR). Cumulative incidence was plotted using Kaplan-Meier, with risk assessment via Cox regression. RESULTS: The study included 2192 patients in each cohort. The 3-year cumulative incidence of atopic march progression was lower in the DUPI-cohort than the CONV-cohort (20.09% vs 27.22%; P < .001). The DUPI-cohort demonstrated significant risk reduction in atopic march progression (hazard ratio [HR] 0.68, 95% CI 0.55-0.83), individual asthma (HR 0.60, 0.45-0.81), and individual AR (HR 0.69, 0.54-0.88). Younger patients on dupilumab exhibited a greater risk reduction for atopic march progression and individual asthma, contrasting with the opposite age-related pattern for individual AR. LIMITATIONS: Observational study. CONCLUSION: Among pediatric AD patients, dupilumab was associated with reduced risk of atopic march progression compared with conventional therapies.

16.
Appl Microbiol Biotechnol ; 108(1): 242, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38416210

RESUMEN

Flavivirus virus-like particles (VLPs) exhibit a striking structural resemblance to viral particles, making them highly adaptable for various applications, including vaccines and diagnostics. Consequently, increasing VLPs production is important and can be achieved by optimizing expression plasmids and cell culture conditions. While attempting to express genotype III (GIII) Japanese encephalitis virus (JEV) VLPs containing the G104H mutation in the envelope (E) protein, we failed to generate VLPs in COS-1 cells. However, VLPs production was restored by cultivating plasmid-transfected cells at a lower temperature, specifically 28 °C. Furthermore, we observed that the enhancement in JEV VLPs production was independent of amino acid mutations in the E protein. The optimal condition for JEV VLPs production in plasmid-transfected COS-1 cells consisted of an initial culture at 37 °C for 6 h, followed by a shift to 28 °C (37/28 °C) for cultivation. Under 37/28 °C cultivation conditions, flavivirus VLPs production significantly increased in various mammalian cell lines regardless of whether its expression was transiently transfected or clonally selected cells. Remarkably, clonally selected cell lines expressing flavivirus VLPs consistently achieved yields exceeding 1 µg/ml. Binding affinity analyses using monoclonal antibodies revealed similar binding patterns for VLPs of genotype I (GI) JEV, GIII JEV, West Nile virus (WNV), and dengue virus serotype 2 (DENV-2) produced under both 37 °C or 37/28 °C cultivation conditions. In summary, our study demonstrated that the production of flavivirus VLPs can be significantly improved under 37/28 °C cultivation conditions without affecting the conformational structure of the E protein. KEYPOINTS: • Low-temperature culture (37/28 °C) enhances production of flavivirus VLPs. • Flavivirus VLPs consistently achieved yields exceeding 1 µg/ml. • 37/28 °C cultivation did not alter the structure of flavivirus VLPs.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Flavivirus , Chlorocebus aethiops , Animales , Flavivirus/genética , Temperatura , Virus de la Encefalitis Japonesa (Especie)/genética , Frío , Células COS , Mamíferos
17.
Antonie Van Leeuwenhoek ; 117(1): 8, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38170331

RESUMEN

During our studies on the microorganism diversity from air of manufacturing shop in a pharmaceutical factory in Shandong province, China, a Gram-stain-positive, aerobic, cocci-shaped bacterium, designated LY-0111T, was isolated from a settling dish. Strain LY-0111T grew at temperature of 10-42 °C (optimum 35 °C), pH of 5.0-10.0 (optimum pH 7.0) and NaCl concentration of 1-12% (optimum 0.5-3%, w/v). Based on the 16S rRNA gene sequence analysis, the strain shared the highest sequence similarities to Nesterenkonia halophila YIM 70179T (96.2%), and was placed within the radiation of Nesterenkonia species in the phylogenetic trees. The genome of the isolate was sequenced, which comprised 2,931,270 bp with G + C content of 66.5%. A supermatrix tree based on the gene set bac120 indicated that LY-0111T was close related to Nesterenkonia xinjiangensis YIM 70097T (16S rRNA gene sequence similarity 95.3%). Chemotaxonomic analysis indicated that the main respiratory quinones were MK-7, MK-8, and MK-9, the predominant cellular fatty acids were anteiso-C15:0 and iso-C15:0, and the major polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. According to the phenotypic, chemotaxonomic and phylogenetic features, strain LY-0111T is considered to represent a novel species, for which the name Nesterenkonia aerolata sp. nov. is proposed. The type strain is LY-0111T (= JCM 36375T = GDMCC 1.3945T). In addition, Nesterenkonia jeotgali was proposed as a later synonym of Nesterenkonia sandarakina, according to the ANI (96.8%) and dDDH (72.9%) analysis between them.


Asunto(s)
Ácidos Grasos , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Hibridación de Ácido Nucleico , Ácidos Grasos/análisis , Preparaciones Farmacéuticas , China , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Fosfolípidos/análisis
18.
BMC Nephrol ; 25(1): 194, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38862914

RESUMEN

BACKGROUND: Early identification of high-risk individuals with cisplatin-induced nephrotoxicity (CIN) is crucial for avoiding CIN and improving prognosis. In this study, we developed and validated a CIN prediction model based on general clinical data, laboratory indications, and genetic features of lung cancer patients before chemotherapy. METHODS: We retrospectively included 696 lung cancer patients using platinum chemotherapy regimens from June 2019 to June 2021 as the traing set to construct a predictive model using Absolute shrinkage and selection operator (LASSO) regression, cross validation, and Akaike's information criterion (AIC) to select important variables. We prospectively selected 283 independent lung cancer patients from July 2021 to December 2022 as the test set to evaluate the model's performance. RESULTS: The prediction model showed good discrimination and calibration, with AUCs of 0.9217 and 0.8288, sensitivity of 79.89% and 45.07%, specificity of 94.48% and 94.81%, in the training and test sets respectively. Clinical decision curve analysis suggested that the model has value for clinical use when the risk threshold ranges between 0.1 and 0.9. Precision-Recall (PR) curve shown in recall interval from 0.5 to 0.75: precision gradually declines with increasing Recall, up to 0.9. CONCLUSIONS: Predictive models based on laboratory and demographic variables can serve as a beneficial complementary tool for identifying high-risk populations with CIN.


Asunto(s)
Antineoplásicos , Cisplatino , Neoplasias Pulmonares , Humanos , Cisplatino/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , China/epidemiología , Neoplasias Pulmonares/tratamiento farmacológico , Estudios de Casos y Controles , Antineoplásicos/efectos adversos , Estudios Retrospectivos , Anciano , Enfermedades Renales/inducido químicamente , Medición de Riesgo
19.
Mycoses ; 67(1): e13680, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38214420

RESUMEN

CIITA, a member of NOD-like receptor (NLR) family, is the major MHC II trans-activator and mediator of Th1 immunity, but its function and interaction with NLRP3 have been little studied. We found activation of NLRP3 inflammasome, increased expression of CIITA, CBP, pSTAT1, STAT1, MHC II, IFN-γ and IFN-γ-inducible chemokines (CCL1 and CXCL8), and colocalisation of NLRP3 with CIITA in Malassezia folliculitis lesions, Malassezia globosa-infected HaCaT cells and mouse skin. CoIP with anti-CIITA or anti-NLRP3 antibody pulled down NLRP3 or both CIITA and ASC. NLRP3 silencing or knockout caused CIITA downexpression and their colocalisation disappearance in HaCaT cells and mouse skin of Nlrp3-/- mice, while CIITA knockdown had no effect on NLRP3, ASC, IL-1ß and IL-18 expression. NLRP3 inflammasome inhibitors and knockdown significantly suppressed IFN-γ, CCL1, CXCL8 and CXCL10 levels in M. globosa-infected HaCaT cells. CCL1 and CXCL8 expression was elevated in Malassezia folliculitis lesions and reduced in Nlrp3-/- mice. These results demonstrate that M. globosa can activate NLRP3 inflammasome, CIITA/MHC II signalling and IFN-γ-inducible chemokines in human keratinocytes and mouse skin. NLRP3 may regulate CIITA by their binding and trigger Th1 immunity by secreting CCL1 and CXCL8/IL-8, contributing to the pathogenesis of Malassezia-associated skin diseases.


Asunto(s)
Quimiocinas C , Foliculitis , Malassezia , Humanos , Ratones , Animales , Interferón gamma , Interferones , Antígenos de Histocompatibilidad Clase II/genética , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Inflamasomas , Regiones Promotoras Genéticas , Transactivadores/genética , Transactivadores/metabolismo , Quimiocinas/genética , Queratinocitos
20.
Foodborne Pathog Dis ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133119

RESUMEN

Toxoplasma gondii is a widespread protozoan parasite approximately infecting one-third of the world population and can cause serious public health problems. In this study, we investigated the protective effect of the attenuated vaccine Pru:Δcdpk2 against acute toxoplasmosis and explored the underlying immune mechanisms of the protection in pigs. The systemic T-cell and natural killer (NK) cell responses were analyzed, including kinetics, phenotype, and multifunctionality (interferon [IFN]-γ, tumor necrosis factor [TNF]-α), and the IFN-γ levels were analyzed in PBMCs. Our results showed that T. gondii-specific antibodies were induced by Pru:Δcdpk2. After challenging with RH, the antibodies were able to respond quickly in the immunized group, and the expression level was significantly higher than that in the unimmunized group. The expression level of IFN-γ significantly increased after vaccination, and the CD3+ γδ-, NK, and CD3+ γδ+ cell subsets also significantly increased. At the same time, functional analysis indicated that these cells were polarized toward a Th1 phenotype, showing the ability to secrete IFN-γ and TNF-α. The CD4+CD8α-T cell population exhibited a higher frequency of IFN-γ+ producing cells compared with the CD4-CD8α+ and CD4+CD8α+ cell populations during the early days of vaccination. Our results indicated that the attenuated vaccine could induce the expression of NK, γδ, and CD3αß cells in pigs, and IFN-γ and TNF-α secreted by these cells are important for resistance to T. gondii infection.

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