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1.
Proc Natl Acad Sci U S A ; 119(22): e2118124119, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35617426

RESUMEN

Fragile X­associated tremor/ataxia syndrome (FXTAS) is a debilitating late-onset neurodegenerative disease in premutation carriers of the expanded CGG repeat in FMR1 that presents with a spectrum of neurological manifestations, such as gait ataxia, intention tremor, and parkinsonism [P. J. Hagerman, R. J. Hagerman, Ann. N. Y. Acad. Sci. 1338, 58­70 (2015); S. Jacquemont et al., JAMA 291, 460­469 (2004)]. Here, we performed whole-genome sequencing (WGS) on male premutation carriers (CGG55­200) and prioritized candidate variants to screen for candidate genetic modifiers using a Drosophila model of FXTAS. We found 18 genes that genetically modulate CGG-associated neurotoxicity in Drosophila, such as Prosbeta5 (PSMB5), pAbp (PABPC1L), e(y)1 (TAF9), and CG14231 (OSGEPL1). Among them, knockdown of Prosbeta5 (PSMB5) suppressed CGG-associated neurodegeneration in the fly as well as in N2A cells. Interestingly, an expression quantitative trait locus variant in PSMB5, PSMB5rs11543947-A, was found to be associated with decreased expression of PSMB5 and delayed onset of FXTAS in human FMR1 premutation carriers. Finally, we demonstrate evidence that PSMB5 knockdown results in suppression of CGG neurotoxicity via both the RAN translation and RNA-mediated toxicity mechanisms, thereby presenting a therapeutic strategy for FXTAS.


Asunto(s)
Ataxia , Síndrome del Cromosoma X Frágil , Complejo de la Endopetidasa Proteasomal , Temblor , Animales , Ataxia/genética , Modelos Animales de Enfermedad , Drosophila melanogaster , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Humanos , Masculino , Complejo de la Endopetidasa Proteasomal/genética , Temblor/genética
2.
Proteins ; 92(10): 1147-1160, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38441337

RESUMEN

Antibodies represent a crucial class of complex protein therapeutics and are essential in the treatment of a wide range of human diseases. Traditional antibody discovery methods, such as hybridoma and phage display technologies, suffer from limitations including inefficiency and a restricted exploration of the immense space of potential antibodies. To overcome these limitations, we propose a novel method for generating antibody sequences using deep learning algorithms called AbDPP (target-oriented antibody design with pretraining and prior biological knowledge). AbDPP integrates a pretrained model for antibodies with biological region information, enabling the effective use of vast antibody sequence data and intricate biological system understanding to generate sequences. To target specific antigens, AbDPP incorporates an antibody property evaluation model, which is further optimized based on evaluation results to generate more focused sequences. The efficacy of AbDPP was assessed through multiple experiments, evaluating its ability to generate amino acids, improve neutralization and binding, maintain sequence consistency, and improve sequence diversity. Results demonstrated that AbDPP outperformed other methods in terms of the performance and quality of generated sequences, showcasing its potential to enhance antibody design and screening efficiency. In summary, this study contributes to the field by offering an innovative deep learning-based method for antibody generation, addressing some limitations of traditional approaches, and underscoring the importance of integrating a specific antibody pretrained model and the biological properties of antibodies in generating novel sequences. The code and documentation underlying this article are freely available at https://github.com/zlfyj/AbDPP.


Asunto(s)
Aprendizaje Profundo , Humanos , Algoritmos , Anticuerpos/química , Anticuerpos/inmunología , Anticuerpos/metabolismo , Secuencia de Aminoácidos , Antígenos/inmunología , Antígenos/química
3.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34643213

RESUMEN

Understanding the impact of non-coding sequence variants on complex diseases is an essential problem. We present a novel ensemble learning framework-CASAVA, to predict genomic loci in terms of disease category-specific risk. Using disease-associated variants identified by GWAS as training data, and diverse sequencing-based genomics and epigenomics profiles as features, CASAVA provides risk prediction of 24 major categories of diseases throughout the human genome. Our studies showed that CASAVA scores at a genomic locus provide a reasonable prediction of the disease-specific and disease category-specific risk prediction for non-coding variants located within the locus. Taking MHC2TA and immune system diseases as an example, we demonstrate the potential of CASAVA in revealing variant-disease associations. A website (http://zhanglabtools.org/CASAVA) has been built to facilitate easily access to CASAVA scores.


Asunto(s)
Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Genoma Humano , Genómica , Humanos , Aprendizaje Automático
4.
Skin Res Technol ; 30(8): e13904, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39149890

RESUMEN

BACKGROUND: Pressure ulcer (PU) is known to be associated with abnormalities of micronutrient status. However, to date, it is not clear whether a causal relationship exists between circulating levels of micronutrients and their supplementations and PU. METHODS: A two-sample Mendelian randomization (MR) study was conducted using summary statistics from Genome-Wide Association Studies (GWAS). Genetic instrumental variables (IVs) for 13 micronutrients were identified from a GWAS of 67 582 participants, IVs for supplement zinc were acquired from 18 826 cases and 44 255 880 controls, and IVs for PU were obtained from 663 PUs and 207 482 controls. The MR analysis was conducted using the MR base platform. The main analysis method was inverse variance weighted (IVW) analysis, supplemented by MR Egger, Weighted median, Weighted mode, and Simple mode analyses. Heterogeneity was assessed using Cochran's Q statistic for MR-IVW and Rucker's Q statistic for MR-Egger. Pleiotropy was determined by the MR-Egger regression. Sensitivity analysis was conducted using the leave-one-out method, and publication bias was evaluated using funnel plots. RESULTS: Genetically predicted lower circulating zinc levels were found to be causally linked to the development of PU (OR = 0.758, 95%CI 0.583-0.987, P = 0.040). However, there was no significant evidence of a causal relationship between supplemental zinc intake and PU development (P > 0.05). Additionally, no causal association was observed between the other circulating micronutrients and the occurrence of PU. Furthermore, there was no indication of horizontal pleiotropy or heterogeneity among genetic variants (P > 0.05), and the robustness of the findings was confirmed through leave-one-out tests and funnel plots. CONCLUSIONS: Our findings indicate a potential causal association between circulating zinc levels and decreased risk of PU. However, zinc supplementation did not demonstrate a significant reduction in the risk of PU. Further research is warranted to elucidate the underlying mechanisms through which zinc influences the pathogenesis of PU and evaluate the efficacy of zinc supplementation in the prevention and management of PU.


Asunto(s)
Suplementos Dietéticos , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Micronutrientes , Úlcera por Presión , Zinc , Humanos , Úlcera por Presión/genética , Úlcera por Presión/sangre , Úlcera por Presión/epidemiología , Micronutrientes/sangre , Zinc/sangre , Zinc/deficiencia , Polimorfismo de Nucleótido Simple/genética
5.
Mar Drugs ; 22(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39195472

RESUMEN

Chlamydomonas reinhardtii polysaccharides (CRPs) are bioactive compounds derived from C. reinhardtii, yet their potential in cancer therapy remains largely unexplored. This study optimized the ultrasound-assisted extraction conditions using response surface methodology and proceeded with the isolation and purification of these polysaccharides. The optimal extraction conditions were identified as a sodium hydroxide concentration of 1.5%, ultrasonic power of 200 W, a solid-to-liquid ratio of 1:25 g/mL, an ultrasonic treatment time of 10 min, and a water bath duration of 2.5 h, yielding an actual extraction rate of 5.71 ± 0.001%, which closely aligns with the predicted value of 5.639%. Infrared analysis revealed that CRP-1 and CRP-2 are α-pyranose structures containing furoic acid, while CRP-3 and CRP-4 are ß-pyranose structures containing furoic acid. Experimental results demonstrated that all four purified polysaccharides inhibited the proliferation of cervical (HeLa) hepatoma (HepG-2) and colon (HCT-116) cancer cells, with CRP-4 showing the most significant inhibitory effect on colon cancer and cervical cancer, achieving inhibition rates of 60.58 ± 0.88% and 40.44 ± 1.44%, respectively, and significantly reducing the migration of HeLa cells. DAPI staining confirmed that the four purified polysaccharides inhibit cell proliferation and migration by inducing apoptosis in HeLa cells. CRP-1 has the most significant inhibitory effect on the proliferation of liver cancer cells. This study not only elucidates the potential application of C. reinhardtii polysaccharides in cancer therapy but also provides a scientific basis for their further development and utilization.


Asunto(s)
Antineoplásicos , Proliferación Celular , Chlamydomonas reinhardtii , Polisacáridos , Polisacáridos/farmacología , Polisacáridos/aislamiento & purificación , Polisacáridos/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/aislamiento & purificación , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Células HeLa , Células Hep G2 , Células HCT116 , Animales , Línea Celular Tumoral
6.
Plant Dis ; 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38170442

RESUMEN

In September 2022, leaf blight symptoms (Fig. 1) were detected on six-year-old kiwi trees (Actinidia chinensis cv. 'Hongyang') in Xuzhou municipality (117.29º E, 34.23º N), Jiangsu Province. Early-stage disease symptoms included light brown necrotic lesions of irregular shape ranging in length from 0.2 to 2.4 cm, which turned into leaf blight after approximately 2 weeks. Those symptoms were similar to those previously reported during a Pestalotiopsis sp. infection on kiwi trees in Turkey (Karakaya 2001). Approximately 20% of the leaves from 300 trees examined in one kiwi orchard, 3000 m2 in size, showed the disease symptoms. Ten leading edges of symptomatic leaves were sterilized with 2% sodium hypochlorite for 1 min, rinsed twice with sterile ddH2O and cultured at 26ºC for 3 days on PDA medium containing 50 µg/ml chloramphenicol. The fungal colonies were collected, and the single spore isolation method was used to obtain four isolates. The obtained isolates showed white aerial mycelia that turned greyish after 2 days of cultivation on PDA medium at 26ºC. ITS (OR054113, OR054153-OR054155), TUB2 (OR060951-OR060953, OR249978), and CMD (OR255947-OR255950) genes were amplified using the ITS1/ITS4, BT2a/BT2b and CMD5/CMD6 primers, respectively (Visagie et al. 2014a). The obtained ITS, TUB2, and CMD sequences shared 99.81%-100%, 96.72%-96.96%, and 90.17%-92.58% homology compared to the ex-type strain P. oxalicum CBS 219.30 (MH855125, KF296462, and KF296367), while the obtained ITS and TUB2 sequences showed 99.62%-99.81%, and 96.46%-96.72% identity compared to the representative strain P. oxalicum DTO 179B9 (KJ775647 and KJ775140) (Visagie et al. 2014b). The sequences obtained also showed high homology compared to P. oxalicum HP7-1 (ITS: 99.81%-100% homology; TUB2: 98.98%-99.38% homology; CMD: 94.71%-95.10% homology) (Li et al. 2022). A molecular phylogenetic tree was constructed using MEGA X with representative Penicillium strains retrieved from GenBank (Fig. 2). Microscope observations revealed the presence of curved septate hyphae. Conidia were colorless, unicellular, and ellipsoidal (5-8 µm in length; > 2000 observations), whereas conidiophores were mainly monoverticillate (approximately 20% of the conidiophores were biverticillate) (50-70 µm in length; 43 observations) and contained cylindrical phialides (13-15 µm in length). These findings are consistent with P. oxalicum morphology (Wu et al. 2022; Zheng et al. 2023). The pathogenicity of the four isolates was screened using healthy non-detached 'Hongyang' kiwi leaves. Fifteen leaves from five different two-month-old trees were used for each isolate, with three repetitions. For inoculation, a 10 mL solution containing 1 × 106 spores/mL was sprayed on the leaves. Sterilized water was used in the control experiment, which was carried out using fifteen leaves from five different two-month-old trees, with three repetitions. Inoculated trees were stored at 26ºC and 60% relative humidity for 2 days. All the infected leaves had necrotic lesions and leaf blight symptoms comparable to those found in the field, but the control leaves had no lesions. The pathogen was recovered, and its identity was confirmed by ITS sequencing and morphology analysis, fulfilling Koch's postulates. P. oxalicum is a common cause of blue mould in postharvest fruits (Tang et al. 2020). P. oxalicum has been recently reported as the causal agent of leaf spot in pineapple (Wu et al. 2022; Zheng et al. 2023), and leaf blight on maize (Han et al. 2023). Although Alternaria sp., Glomerella cingulate, Pestalotiopsis sp., Phomopsis sp., and Phoma sp. were previously isolated from kiwi leaves with blight symptoms (Kim et al. 2017), this is the first report of P. oxalicum causing leaf blight on kiwi trees worldwide. P. oxalicum is a well-known source of mycotoxins, such as secalonic acid (Otero et al. 2020), indicating that its presence in kiwifruit orchards may pose a significant risk to human health. The discovery of this hazardous pathogen in kiwi trees must drive the development of management strategies. Kiwifruit is an important dietary source of vitamins, fiber, folate, and potassium, and China is the major producer of kiwifruit, with more than 1.2 million metric tons harvested in 2021. This report will help to generate a better understanding of the pathogens affecting kiwifruit orchards in China.

7.
Int Wound J ; 21(3): e14829, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38494175

RESUMEN

This review aims to systematically evaluate the association between hypertension and pressure ulcer (PU). PubMed, Embase, Web of Science, and Cochrane Library were searched for studies from their inception until September 12, 2023. Literature search, data extraction, and quality assessment were conducted independently by two researchers. The random-effects model was used to calculate the combined odds ratio (OR) and corresponding 95% confidence interval (CI) of hypertension in patients with PU; subgroup analyses were performed to explore the source of between-study heterogeneity; sensitivity analysis was used to test the robust of the combined result; and funnel plot and Egger's test were used to assess the publication bias. Finally, a total of 19 studies with 564 716 subjects were included; the overall pooled result showed no significant association between hypertension and risk of developing PU (OR = 1.15, 95% CI = 0.90-1.47, p = 0.27); and the sensitivity analysis and publication bias analysis showed robust of the combined result. Subgroup analysis indicated a significant association between hypertension and PU when the primary disease was COVID-19 (OR = 1.73, 95% CI = 1.35-2.22, p < 0.0001). No association between hypertension and PU was seen in subgroup analysis on the patient source and study design. In sum, there is no significantly statistical association between hypertension and the occurrence of PU in most cases, while the risk of PU significantly elevates among COVID-19 patients combined with hypertension regardless of patient source and study design.


Asunto(s)
COVID-19 , Hipertensión , Úlcera por Presión , Humanos , Úlcera por Presión/epidemiología , Úlcera por Presión/etiología , Hipertensión/epidemiología , Proyectos de Investigación
8.
Neurobiol Dis ; 185: 106257, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37562656

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder influenced by a complex interplay of environmental, epigenetic, and genetic factors. DNA methylation (5mC) and hydroxymethylation (5hmC) are DNA modifications that serve as tissue-specific and temporal regulators of gene expression. TET family enzymes dynamically regulate these epigenetic modifications in response to environmental conditions, connecting environmental factors with gene expression. Previous epigenetic studies have identified 5mC and 5hmC changes associated with AD. In this study, we performed targeted resequencing of TET1 on a cohort of early-onset AD (EOAD) and control samples. Through gene-wise burden analysis, we observed significant enrichment of rare TET1 variants associated with AD (p = 0.04). We also profiled 5hmC in human postmortem brain tissues from AD and control groups. Our analysis identified differentially hydroxymethylated regions (DhMRs) in key genes responsible for regulating the methylome: TET3, DNMT3L, DNMT3A, and MECP2. To further investigate the role of Tet1 in AD pathogenesis, we used the 5xFAD mouse model with a Tet1 KO allele to examine how Tet1 loss influences AD pathogenesis. We observed significant changes in neuropathology, 5hmC, and RNA expression associated with Tet1 loss, while the behavioral alterations were not significant. The loss of Tet1 significantly increased amyloid plaque burden in the 5xFAD mouse (p = 0.044) and lead to a non-significant trend towards exacerbated AD-associated stress response in 5xFAD mice. At the molecular level, we found significant DhMRs enriched in genes involved in pathways responsible for neuronal projection organization, dendritic spine development and organization, and myelin assembly. RNA-Seq analysis revealed a significant increase in the expression of AD-associated genes such as Mpeg1, Ctsd, and Trem2. In conclusion, our results suggest that TET enzymes, particularly TET1, which regulate the methylome, may contribute to AD pathogenesis, as the loss of TET function increases AD-associated pathology.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , 5-Metilcitosina , Epigénesis Genética , Metilación de ADN , Factores de Transcripción/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo
9.
Nutr Metab Cardiovasc Dis ; 32(3): 641-647, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35115210

RESUMEN

BACKGROUND AND AIMS: Hyperuricemia is widely thought as a risk factor for myocardial infarction (MI) and all-cause mortality; however, the relation of serum uric acid (sUA) and subclinical myocardial injury (SCeMI) remains unclear. We hypothesize that sUA is associated with subclinical myocardial injury. METHODS AND RESULTS: A total of 5880 adult individuals (57.9 ± 13.0 years, 54.23% women) without known cardiovascular disease from National Health and Nutrition Examination Survey (NHANES) III were included. Determined by Cardiac Infarction Injury Score (CIIS) from 12-lead electrocardiogram, SCeMI was defined by CIIS ≥10 units. The relationship between sUA and SCeMI was analyzed by using logistic regression models and the smooth curve fitting. Subgroup analyses were conducted. After adjusting for potential confounding variables, the smooth curve fitting revealed a non-linear relationship between sUA level and SCeMI. When sUA was above the inflection point 266.5 µmol/L, each 100 unit increase in sUA increase the risk of SCeMI by 15%. In women group, when sUA>340.3 µmol/L, each 100 unit increase in sUA increase the risk of SCeMI by 71%, but no significant correlation was observed in men group. CONCLUSIONS: Our findings confirm that sUA is an independent risk factor for subclinical myocardial injury after adjusting for potential confounding variables, and existence of such an association in women only, which require more random control trials to confirm the strategy of cardiovascular disease prevention based on sUA reduction in female.


Asunto(s)
Hiperuricemia , Infarto del Miocardio , Adulto , Femenino , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiología , Masculino , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Infarto del Miocardio/prevención & control , Encuestas Nutricionales , Factores de Riesgo , Ácido Úrico
10.
Biochem Biophys Res Commun ; 533(3): 404-409, 2020 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-32972753

RESUMEN

Due to the increasing drug-resistant of Candida albicans (C. albicans), there is an urgent need to develop a novel therapeutic agent for C. albicans induced inflammatory disease treatment. Antimicrobial peptides (AMPs) are regarded as one of the most promising antifungal drugs. However, most of the designed AMPs showed side-effects. In the present study, 10 novel peptides were designed based on the sequence of frog skin secretions peptide (Ranacyclin AJ). Among them, AKK8 (RWRFKWWKK) exhibited the strongest antifungal effect against both standard and clinically isolated drug-resistant C. albicans. AKK8 killed C. albicans (within 30 min), and the antifungal effect lasted for 24 h, showed an efficient and long lasted antifungal effect against C. albicans. Notably, AKK8 showed low toxicity to human red blood cells and high stability in human serum. Moreover, AKK8 administration showed therapeutic effects on systemic infections mice induced by the clinical drug-resistant C. albicans, in a dose-depended manner. These findings suggested that AKK8 may be a potential candidate for the anti-inflammation treatments for diseases caused by clinical drug-resistant C. albicans.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Animales , Antifúngicos/sangre , Antifúngicos/química , Candida albicans/ultraestructura , Candidiasis/sangre , Candidiasis/tratamiento farmacológico , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Citocinas/sangre , Diseño de Fármacos , Farmacorresistencia Fúngica/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Ratones , Péptidos/sangre , Péptidos/química , Péptidos/farmacología
11.
Molecules ; 24(12)2019 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-31238562

RESUMEN

This study aimed to screen an effective flavonoid with promising whitening and antioxidant capacities, and design flavonoid-loaded niosomes to improve its solubility, stability, and penetration. In vitro anti-tyrosinase and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging experiments were conducted to investigate the whitening and antioxidant capacities of several flavonoids, including quercetin, morin, festin, myricetin, rutin, and breviscapine. The conductivity, viscosity, and particle size of Span60-RH40-based formulation of nonionic surfactant vesicles (niosomes) with different mass ratios were studied to determine the most appropriate formulation. Drug-loaded niosomes were characterized for size, zeta potential, morphology, and entrapment efficiency. The photostability, solubility, release behavior, ex vivo drug penetration, and skin retention were also studied. The results showed that quercetin has considerable whitening and antioxidant capacities and Span60-RH40 at a mass ratio of 9:11 forms spherical or oval niosomes of 97.6 ± 3.1 nm with a zeta potential range of 31.1 ± 0.9 mV, and drug entrapment efficiency as high as 87.3 ± 1.6%. Niosomes remarkably improved the solubility and photostability of quercetin. Furthermore, compared to quercetin solution, quercetin-niosomes had the advantages of sustained release and improved transdermal penetration, with skin retention 2.95 times higher than quercetin solution.


Asunto(s)
Antioxidantes/administración & dosificación , Portadores de Fármacos , Liposomas , Monofenol Monooxigenasa/antagonistas & inhibidores , Nanopartículas , Inhibidores de Proteasas/administración & dosificación , Quercetina/administración & dosificación , Administración Cutánea , Animales , Antioxidantes/química , Química Farmacéutica , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Estabilidad de Medicamentos , Flavonoides , Liposomas/química , Estructura Molecular , Nanopartículas/química , Inhibidores de Proteasas/química , Quercetina/química , Ratas , Solubilidad
12.
Chemistry ; 23(55): 13633-13637, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28833747

RESUMEN

The 2-aminophenylaluminum dihydride (2-TMP-C6 H4 )AlH2  (2) has been prepared and characterized for the first time. Compound 2 features an intramolecular N⋅⋅⋅Al donor-acceptor bond. 2 reacted with N-methylpyrrole and N-methylindole (both at 50 °C) by means of the elusive AlH C(sp2 )-H dehydroalumination to aluminum heteroaryls (3 and 4). Moreover, 2 reacted with PhCCSiMe3 (at room temperature) and Ph2 CCNR (R=iPr or 2,6-iPr2 C6 H3 , at -30 to 20 °C ) to yield aluminaindene heterocycle (8) and alumina-aza-naphthalene heterocycle (9 and 10), respectively. These reactions underwent hydroalumination followed by AlH C(sp2 )-H dehydroalumination. The reaction mechanism has been studied by combining experiment and quantum chemical calculations, with the result that the key heteroarene or arene C(sp2 )-H bond activation is involved under cooperative interaction by the inherent N/Al donor/acceptor pair. The reported reactions open a straightforward route to heteroaryl and unique heterocyclic aluminum compounds.

13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(2): 432-8, 2014 Apr.
Artículo en Zh | MEDLINE | ID: mdl-25039155

RESUMEN

Expression conditions of induction strategies for the cytoplasmic inclusion bodies (IBs) production of liver targeted interferon IFN-CSP by recombinant Escherichia coli (E. coli) BL21 (DE3) were optimized in shake-flask cultures in this study. The factors of the optimized protocol included in the present study were pH, inducer IPTG (isopropyl beta-D-thiogalactoside) concentration, culture growth temperature, incubation time and induction point. The effects of those factors were investigated by 'single variable at a time' method, aimed to analyze characterization of the recombinant strain. Orthogonal experimental design was further used to optimize the above critical factors for IFN-CSP production. According to the expression optimization result, it was confirmed that the main influence factors were cell density and induction temperature. The IFN-CSP gene expression optimized conditions were: pH value of the culture medium was 6.0, culture temperature 37 degrees C, adding IPTG to final concentration 0.4 mmol/L when the recombinant strain growth density OD600 achieved 0.8 and induction time 4 h. At this point, the IBs represented 74.3% of the total cellular protein. Compared with the non-optimized condition, IFN-CSP production obtained in optimized induction strategies were increased by approx. 1.2-fold. The optimized induction strategy yielded 688.8 mg/L of IFN-CSP, providing experimental data to study the biology activity and productive technology of IFN-CSP.


Asunto(s)
Biotecnología/métodos , Técnicas de Cultivo de Célula/métodos , Escherichia coli/metabolismo , Interferones/biosíntesis , Medios de Cultivo/química , Expresión Génica , Hígado , Temperatura
14.
IEEE Trans Cybern ; 54(2): 1062-1074, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38133985

RESUMEN

Multiobjective particle swarm optimization (MOPSO) has been proven effective in solving multiobjective problems (MOPs), in which the evolutionary parameters and leaders are selected randomly to develop the diversity. However, the randomness would cause the evolutionary process uncertainty, which deteriorates the optimization performance. To address this issue, a robust MOPSO with feedback compensation (RMOPSO-FC) is proposed. RMOPSO-FC provides a novel closed-loop optimization framework to reduce the negative influence of uncertainty. First, Gaussian process (GP) models are established by dynamically updated archives to obtain the posterior distribution of particles. Then, the feedback information of particle evolution can be collected. Second, an intergenerational binary metric is designed based on the feedback information to evaluate the evolutionary potential of particles. Then, the particles with negative evolutionary directions can be identified. Third, a compensation mechanism is presented to correct the negative evolution of particles by modifying the particle update paradigm. Then, the compensated particles can maintain the positive exploration toward the true PF. Finally, the comparative simulation results illustrate that the proposed RMOPSO-FC can provide superior search capability of PFs and algorithmic robustness over multiple runs.

15.
ACS Appl Mater Interfaces ; 16(9): 11730-11739, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38407090

RESUMEN

Photoluminescent metal-organic frameworks (MOFs) have been a subject of considerable interest for many years. However, the regulation of excited states of MOFs at the single crystal level remains restricted due to a lack of control methods. The singlet-triplet emissive property can be significantly influenced by crystal conformational distortions. This review introduces an intelligent responsive MOF material, denoted as LIFM-SHL-3a, characterized by flexible C-S-C bonds. LIFM-SHL-3a integrates elastic structural dynamics with fluorescence and room temperature phosphorescence (RTP) modulation under heating conditions. The deformable carbon-sulfur bond essentially propels the distortion of molecular conformation and alters the stacking mode, as illustrated by single-crystal-to-single-crystal transformation detection. The deformation of flexible C-S-C bonds leads to different noncovalent interactions in the crystal system, thereby achieving modulation of the fluorescence (F) and RTP bands. In the final state structure, the ratio of fluorescence is 66.7%, and the ratio of RTP is 32.6%. This stands as a successful demonstration of modulating F/RTP within the dynamic MOF, unlocking potential applications in optical sensing and beyond. Especially, a PL thermometer with a relative sensitivity of 0.096-0.104%·K-1 in the range of 300-380 K and a H2S probe with a remarkably low LOD of 125.80 nM can be obtained using this responsive MOF material of LIFM-SHL-3a.

16.
Chem Sci ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39386906

RESUMEN

In this study, Förster resonance energy transfer (FRET) is harnessed to construct a novel stimulus-responsive long-persistent luminescence (LPL) system. Two organic molecules, DPSD and DPOD, were initially found to have no afterglow under ambient conditions, but exhibited prolonged afterglow upon friction with paper, showing a significantly promoted transition of triplet excited states. Substituting paper with α-cellulose (the main composition of paper) reveals a novel host-guest long afterglow system and allows for a deeper investigation of the above paper-promoted LPL phenomenon. The activation of the LPL effect was achieved by matrixing these components through a grinding process, capitalizing on the efficient FRET from the host to the guest owing to the appropriate energy level match, and the robust intersystem crossing (ISC) capability of the guest. This model presents a new matrix strategy to achieve efficient LPL by a facile, low cost and easy-to-handle process. Furthermore, we successfully implemented anti-counterfeiting, encryption and decryption, decoration, and water/heat stimulus-responsive applications of the obtained materials. These advancements bring LPL materials one step closer to practical commercialization.

17.
Stem Cell Res Ther ; 15(1): 22, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273351

RESUMEN

OBJECTIVE: In recent years, cell therapy has emerged as a new research direction in the treatment of diabetes. However, the underlying molecular mechanisms of mesenchymal stem cell (MSC) differentiation necessary to form such treatment have not been clarified. METHODS: In this study, human umbilical cord mesenchymal stem cells (HUC-MSCs) isolated from newborns were progressively induced into insulin-producing cells (IPCs) using small molecules. HUC-MSC (S0) and four induced stage (S1-S4) samples were prepared. We then performed transcriptome sequencing experiments to obtain the dynamic expression profiles of both mRNAs and long noncoding RNAs (lncRNAs). RESULTS: We found that the number of differentially expressed lncRNAs and mRNAs trended downwards during differentiation. Gene Ontology (GO) analysis showed that the target genes of differentially expressed lncRNAs were associated with translation, cell adhesion, and cell connection. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the NF-KB signalling pathway, MAPK signalling pathway, HIPPO signalling pathway, PI3K-Akt signalling pathway, and p53 signalling pathway were enriched in these differentially expressed lncRNA-targeting genes. We also found that the coexpression of the lncRNA CTBP1-AS2 with PROX1 and the lncRNAs AC009014.3 and GS1-72M22.1 with JARID2 mRNA was related to the development of pancreatic beta cells. Moreover, the coexpression of the lncRNAs: XLOC_ 050969, LINC00883, XLOC_050981, XLOC_050925, MAP3K14- AS1, RP11-148K1.12, and CTD2020K17.3 with p53, regulated insulin secretion by pancreatic beta cells. CONCLUSION: In this study, HUC-MSCs combined with small molecule compounds were successfully induced into IPCs. Differentially expressed lncRNAs may regulate the insulin secretion of pancreatic beta cells by regulating multiple signalling pathways. The lncRNAs AC009014.3, Gs1-72m21.1, and CTBP1-AS2 may be involved in the development of pancreatic beta cells, and the lncRNAs: XLOC_050969, LINC00883, XLOC_050981, XLOC_050925, MAP3K14-AS1, RP11-148K1.12, and CTD2020K17.3 may be involved in regulating the insulin secretion of pancreatic beta cells, thus providing a lncRNA catalogue for future research regarding the mechanism of the transdifferentiation of HUC-MSCs into IPCs. It also provides a new theoretical basis for the transplantation of insulin-producing cells into diabetic patients in the future.


Asunto(s)
Insulinas , Células Madre Mesenquimatosas , ARN Largo no Codificante , Humanos , Recién Nacido , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteína p53 Supresora de Tumor/genética , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/metabolismo , Insulinas/genética , Insulinas/metabolismo , Redes Reguladoras de Genes , Perfilación de la Expresión Génica
18.
NPJ Biofilms Microbiomes ; 10(1): 59, 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034349

RESUMEN

The dominant bacteria in the hindgut of calves play an important role in their growth and health, which could even lead to lifelong consequences. However, the identification of core probiotics in the hindgut and its mechanism regulating host growth remain unclear. Here, a total of 1045 fecal samples were analyzed by 16S rRNA gene sequencing from the 408 Holstein dairy calves at the age of 0, 14, 28, 42, 56, and 70 days to characterize the dynamic changes of core taxa. Moreover, the mechanisms of nutrient metabolism of calf growth regulated by core bacteria were investigated using multi-omics analyses. Finally, fecal microbiota transplantation (FMT) in mice were conducted to illustrate the potential beneficial effects of core bacteria. Four calf enterotypes were identified and enterotypes dominated by Bifidobacterium and Oscillospiraceae_UCG-005 were representative. The frequency of enterotype conversion shifted from variable to stable. The close relationship observed between phenotype and enterotype, revealing a potential pro-growth effect of Bifidobacterium, might be implemented by promoting the use of carbohydrate, activating the synthesis of volatile fatty acids, amino acids and vitamin B6, and inhibiting methane production in the hindgut. The FMT results indicated the beneficial effect of Bifidobacterium on host growth and hindgut development. These results support the notion that the Bifidobacterium-dominated fecal microbiome would be an important driving force for promoting the host growth in the early life. Our findings provide new insights into the potential probiotic mining and application strategies to promote the growth of young animals or improve their growth retardation.


Asunto(s)
Bifidobacterium , Trasplante de Microbiota Fecal , Heces , Microbioma Gastrointestinal , ARN Ribosómico 16S , Animales , Heces/microbiología , Bovinos , ARN Ribosómico 16S/genética , Bifidobacterium/genética , Bifidobacterium/crecimiento & desarrollo , Ratones , Trasplante de Microbiota Fecal/métodos , Fenotipo , Probióticos/administración & dosificación , Filogenia , ADN Bacteriano/genética
19.
J Hazard Mater ; 480: 136005, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39369676

RESUMEN

Virulence factor genes (VFGs) pose a potential threat to ecological security and animal health, and have attracted increasing attention in the livestock industry. As one of the primary livestock types, dairy cattle may be an important source of VFG transmission. However, the distribution, transmission, and evolution of VFGs in the gastrointestinal tract and surrounding environment of dairy cattle remain unclear. In the present study, a total of 263 samples were collected from cows, calves, colostrum, farm wastewater, and soil. Metagenomics was conducted to analyze changes in the microbiome and VFGs characteristics in these ecological niches. The VFGs of the cows showed distinct differences between the rumen and feces, and were influenced by the region. The dominant VFG hosts was regulated by their microbial structure. Colostrum administration of cows increased VFG abundance in their newborn calf feces sharply and Enterobacteriaceae became the primary host. While diet was the primary driving force for the temporal variation in calf VFGs. For samples of the surrounding environment, water and soil had higher VFG concentrations and were more structurally stable. Moreover, extensive interactions between the mobile genetic elements and VFGs and gene mobile analysis map based on metagenomic binning both displayed the potential horizontal transfer ability of VFGs in the cows and environment. Our study revealed the prevalence, diffusion, and regulatory factors of VFGs in dairy cattle production systems, providing novel insights into reducing livestock VFGs and limiting their spread.

20.
Microbiome ; 12(1): 216, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39438998

RESUMEN

BACKGROUND: The maternal gut microbiome is the direct and important source of early colonization and development of the neonatal gut microbiome. However, differences in unique and shared features between mothers with different physiological phenotypes and their newborns still lack exhaustive investigation. Here, using a cow-to-calf model, a comprehensive investigation was conducted to elucidate the pattern and characterization of microbial transfer from the maternal source to the offspring. RESULTS: The microbiota in the rumen and feces of dairy cows were divided into two clusters via enterotype analysis. The cows from the enterotype distinguished by Prevotella in the rumen had better production performance, whereas no difference was observed in the cows classified by feces enterotype. Furthermore, through a pairwise combination of fecal and ruminal enterotypes, we screened a group of dairy cows with excellent phenotypes. The gastrointestinal microbiomes of cows with different phenotypes and their offspring differed significantly. The rumen was a more important microbial source for meconium than feces. Transmission of beneficial bacteria from mother to offspring was observed. Additionally, the meconium inherits advantageous metabolic functions of the rumen. The resistome features of the rumen, feces, and meconium were consistent, and resistome abundance from cows to calves showed an expanding trend. The interaction between antibiotic-resistance genes and mobile genetic elements from the rumen to meconium was the most remarkable. The diversity of core metabolites from cows to calves was stable and not affected by differences in phenotypes. However, the abundance of specific metabolites varied greatly. CONCLUSIONS: Our study demonstrates the microbial taxa, metabolic function, and resistome characteristics of maternal and neonatal microbiomes, and reveals the potential vertical transmission of the microbiome from a cow-to-calf model. These findings provide new insights into the transgenerational transmission pattern of the microbiome. Video Abstract.


Asunto(s)
Animales Recién Nacidos , Bacterias , Heces , Microbioma Gastrointestinal , Meconio , Rumen , Animales , Bovinos , Microbioma Gastrointestinal/genética , Heces/microbiología , Femenino , Rumen/microbiología , Meconio/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Embarazo
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