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1.
Nano Lett ; 24(21): 6269-6277, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38743874

RESUMO

Accurately decoding the three-dimensional atomic structure of surface active sites is essential yet challenging for a rational catalyst design. Here, we used comprehensive techniques combining the pair distribution function and reverse Monte Carlo simulation to reveal the surficial distribution of Pd active sites and adjacent coordination environment in palladium-copper nanoalloys. After the fine-tuning of the atomic arrangement, excellent catalytic performance with 98% ethylene selectivity at complete acetylene conversion was obtained in the Pd34Cu66 nanocatalysts, outperforming most of the reported advanced catalysts. The quantitative deciphering shows a large number of active sites with a Pd-Pd coordination number of 3 distributed on the surface of Pd34Cu66 nanoalloys, which play a decisive role in highly efficient semihydrogenation. This finding not only opens the way for guiding the precise design of bimetal nanocatalysts from atomic-level insight but also provides a method to resolve the spatial structure of active sites.

2.
Diabetologia ; 67(6): 1138-1154, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38489029

RESUMO

AIMS/HYPOTHESIS: A hallmark chronic complication of type 2 diabetes mellitus is vascular hyperpermeability, which encompasses dysfunction of the cerebrovascular endothelium and the subsequent development of associated cognitive impairment. The present study tested the hypothesis that during type 2 diabetes circulating small extracellular vesicles (sEVs) exhibit phenotypic changes that facilitate pathogenic disruption of the vascular barrier. METHODS: sEVs isolated from the plasma of a mouse model of type 2 diabetes and from diabetic human individuals were characterised for their ability to disrupt the endothelial cell (EC) barrier. The contents of sEVs and their effect on recipient ECs were assessed by proteomics and identified pathways were functionally interrogated with small molecule inhibitors. RESULTS: Using intravital imaging, we found that diabetic mice (Leprdb/db) displayed hyperpermeability of the cerebrovasculature. Enhanced vascular leakiness was recapitulated following i.v. injection of sEVs from diabetic mice into non-diabetic recipient mice. Characterisation of circulating sEV populations from the plasma of diabetic mice and humans demonstrated increased quantity and size of sEVs compared with those isolated from non-diabetic counterparts. Functional experiments revealed that sEVs from diabetic mice or humans induced the rapid and sustained disruption of the EC barrier through enhanced paracellular and transcellular leak but did not induce inflammation. Subsequent sEV proteome and recipient EC phospho-proteome analysis suggested that extracellular vesicles (sEVs) from diabetic mice and humans modulate the MAPK/MAPK kinase (MEK) and Rho-associated protein kinase (ROCK) pathways, cell-cell junctions and actin dynamics. This was confirmed experimentally. Treatment of sEVs with proteinase K or pre-treatment of recipient cells with MEK or ROCK inhibitors reduced the hyperpermeability-inducing effects of circulating sEVs in the diabetic state. CONCLUSIONS/INTERPRETATION: Diabetes is associated with marked increases in the concentration and size of circulating sEVs. The modulation of sEV-associated proteins under diabetic conditions can induce vascular leak through activation of the MEK/ROCK pathway. These data identify a new paradigm by which diabetes can induce hyperpermeability and dysfunction of the cerebrovasculature and may implicate sEVs in the pathogenesis of cognitive decline during type 2 diabetes.


Assuntos
Permeabilidade Capilar , Diabetes Mellitus Tipo 2 , Vesículas Extracelulares , Animais , Vesículas Extracelulares/metabolismo , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Humanos , Masculino , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Proteômica , Camundongos Endogâmicos C57BL
3.
Bioorg Chem ; 145: 107241, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437761

RESUMO

The discovery of new small molecule-based inhibitors is an attractive field in medicinal chemistry. Structurally diversified heterocyclic derivatives have been investigated to combat multi-drug resistant bacterial infections and they offers several mechanism of action. Methicillin-resistant Staphylococcus aureus (MRSA) is becoming more and more deadly to humans because of its simple method of transmission, quick development of antibiotic resistance, and ability to cause hard-to-treat skin and filmy diseases. The sulfur (SVI) particularly sulfonyl and sulfonamide based heterocyclic moieties, have found to be good anti-MRSA agents. The development of new nontoxic, economical and highly active sulfur (SVI) containing derivatives has become hot research topics in drug discovery research. Presently, more than 150 FDA approved Sulfur (SVI)-based drugs are available in the market, and they are widely used to treat various types of diseases with different therapeutic potential. The present collective data provides the latest advancements in Sulfur (SVI)-hybrid compounds as antibacterial agents against MRSA. It also examines the outcomes of in-vitro and in-vivo investigations, exploring potential mechanisms of action and offering alternative perspectives on the structure-activity relationship (SAR). Sulfur (SVI)-hybrids exhibits synergistic effects with existing drugs to provide antibacterial action against MRSA.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Enxofre/farmacologia
4.
J Am Chem Soc ; 145(49): 26728-26735, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38015199

RESUMO

Deciphering the three-dimensional (3D) insight into nanocatalyst surfaces at the atomic level is crucial to understanding catalytic reaction mechanisms and developing high-performance catalysts. Nevertheless, better understanding the inherent insufficiency of a long-range ordered lattice in nanocatalysts is a big challenge. In this work, we report the local structure of Pd nanocatalysts, which is beneficial for demonstrating the shape-structure-adsorption relationship in acetylene hydrogenation. The 5.27 nm spherical Pd catalyst (Pdsph) shows an ethylene selectivity of 88% at complete acetylene conversion, which is much higher than those of the Pd octahedron and Pd cube and superior to other reported monometallic Pd nanocatalysts so far. By virtue of the local structure revelation combined with the atomic pair distribution function (PDF) and reverse Monte Carlo (RMC) simulation, the atomic surface distribution of the unique compressed strain of Pd-Pd pairs in Pdsph was revealed. Density functional theory calculations verified the obvious weakening of the ethylene adsorption energy on account of the surface strain of Pdsph. It is the main factor to avoid the over-hydrogenation of acetylene. The present work, entailing shape-induced surface strain manipulation and atomic 3D insight, opens a new path to understand and optimize chemical activity and selectivity in the heterogeneous catalysis process.

5.
Biometals ; 36(1): 137-152, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36434352

RESUMO

Selenium (Se) is an essential trace element for the body. Various organs of the body, including the intestine, are affected by its deficiency. Se deficiency can induce oxidative stress and inflammatory responses in the intestine. It can also increase intestinal permeability and decrease intestinal immune function in mammals. However, the detailed studies, conducted on the intestinal molecular mechanisms of Se deficiency-induced injury in poultry, are limited. This study explored the adverse effects of Se deficiency on intestinal permeability and its mechanism. A Se-deficient chicken model was established, and the morphological changes in the chicken duodenum tissues were observed using a light microscope and transmission electron microscope (TEM). Western blotting, qRT-PCR, and other methods were used to detect the expression levels of selenoproteins, oxidative stress indicators, inflammatory factors, tight junction (TJ) proteins, antimicrobial peptides, and other related indicators in intestinal tissues. The results showed that Se deficiency could decrease the expression levels of selenoproteins and antioxidant capacity, activate the nuclear factor kappa-B (NF-κB) pathway, cause inflammation, and decrease the expression levels of TJ proteins and antimicrobial peptides in the duodenum tissues. The study also demonstrated that Se deficiency could increase intestinal permeability and decrease antimicrobial peptides via reactive oxygen species (ROS)/NF-κB. This study provided a theoretical basis for the scientific prevention and control of Se deficiency in poultry. Se deficiency decreased the expression levels of selenoproteins and increased ROS levels to activate the NF-κB pathway, resulting in the production of pro-inflammatory cytokines, reducing the expression levels of TJ protein, and weakening the expression of antimicrobial peptides, which contributed to the higher intestinal permeability. Oxidative stress weakened the expression of antimicrobial peptides.


Assuntos
NF-kappa B , Selênio , Animais , NF-kappa B/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Galinhas/metabolismo , Peptídeos Antimicrobianos , Transdução de Sinais , Duodeno/metabolismo , Selenoproteínas/metabolismo , Mamíferos/metabolismo
6.
Ecotoxicol Environ Saf ; 248: 114303, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36403304

RESUMO

Zinc is an essential nutrient for life, but over-accumulation can result in toxicity. Anthropogenic activities can increase zinc concentrations in aquatic environments (e.g., to ∼0.46-1.00 mg/L), which are above the safe level of 0.1 mg/L. We investigated the behavior and physiology of zebrafish (Danio rerio) in response to environment-related exposure to zinc chloride at 0.0 (Ctrl), 1.0 (ZnCl2-low) and 1.5 (ZnCl2-high) mg/L for 6 weeks (the zinc conversion ratio of zinc chloride is ∼0.48 and the nominal (measured) values were: Ctrl, 0 (∼0.01); ZnCl2-low, 0.48 (∼0.51); ZnCl2-high, 0.72 (∼0.69) mg/L). Low-zinc exposure resulted in significantly increased locomotion and fast moving behaviors, while high-zinc exposure resulted in significantly increased aggression and freezing frequency. Single cell RNA-seq of neurons, astrocytes, and oligodendrocytes of the brain revealed expression of genes related to ion transport, neuron generation, and immunomodulation that were heterogeneously regulated by zinc exposure. Astrocyte-induced central nervous system inflammation potentially integrated neurotoxicity and behavior. Integrated analyses of brain and hepatic transcriptional signatures showed that genes (and pathways) dysregulated by zinc were associated with sensory functions, circadian rhythm, glucose and lipid metabolism, and amyloid ß-protein clearance. Our results showed that environment-related zinc contamination can be heterogeneously toxic to brain cells and can disturb coordination of brain-liver physiology. This may disrupt neurobehavior and cause a neurodegeneration-like syndrome in adult zebrafish.


Assuntos
Transtornos Cronobiológicos , Peixe-Zebra , Animais , Zinco/toxicidade , Peptídeos beta-Amiloides , Encéfalo , Agressão , Fígado
7.
Surg Radiol Anat ; 44(3): 491-494, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35254492

RESUMO

In the routine dissections study for medical postgraduates, a rare anatomical variation between the right leg and the ankle was observed on the Asian male cadaver. The peronaeus tertius muscle in this cadaver's right leg divided into two tendons: the first tendon was attached to the base of the fifth metatarsal bone, and the second tendon was inserted into the base of the fourth metatarsal bone. The purpose of this paper is to provide detailed anatomical case reports, and to discuss the possible causes and mechanisms of the variation by reviewing relevant literature, so as to provide some reference for future anatomical and clinical related disease research.


Assuntos
Variação Anatômica , Tendões , Tornozelo , Articulação do Tornozelo , Cadáver , Humanos , Perna (Membro) , Masculino , Músculo Esquelético
8.
Build Environ ; 218: 109137, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35502296

RESUMO

A COVID-19 outbreak occurred in May 2020 in a public housing building in Hong Kong - Luk Chuen House, located in Lek Yuen Estate. The horizontal cluster linked to the index case' flat (flat 812) remains to be explained. Computational fluid dynamics simulations were conducted to obtain the wind-pressure coefficients of each external opening on the eighth floor of the building. The data were then used in a multi-zone airflow model to estimate the airflow rate and aerosol concentration in the flats and corridors on that floor. Apart from flat 812 and corridors, the virus-laden aerosol concentrations in flats 811, 813, 815, 817 and 819 (opposite to flat 812, across the corridor) were the highest on the eighth floor. When the doors of flats 813 and 817 were opened by 20%, the hourly-averaged aerosol concentrations in these two flats were at least four times as high as those in flats 811, 815 and 819 during the index case's home hours or the suspected exposure period of secondary cases. Thus, the flats across the corridor that were immediately downstream from flat 812 were at the highest exposure risk under a prevailing easterly wind, especially when their doors or windows that connected to the corridor were open. Given that the floorplan and dimension of Luk Chuen House are similar to those of many hotels, our findings provide a probable explanation for COVID-19 outbreaks in quarantine hotels. Positive pressure and sufficient ventilation in the corridor would help to minimise such cross-corridor infections.

9.
Nat Chem Biol ; 15(11): 1035-1042, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31451763

RESUMO

Until recently, the existence of extracellular kinase activity was questioned. Many proteins of the central nervous system are targeted, but it remains unknown whether, or how, extracellular phosphorylation influences brain development. Here we show that the tyrosine kinase vertebrate lonesome kinase (VLK), which is secreted by projecting retinal ganglion cells, phosphorylates the extracellular protein repulsive guidance molecule b (RGMb) in a dorsal-ventral descending gradient. Silencing of VLK or RGMb causes aberrant axonal branching and severe axon misguidance in the chick optic tectum. Mice harboring RGMb with a point mutation in the phosphorylation site also display aberrant axonal pathfinding. Mechanistic analyses show that VLK-mediated RGMb phosphorylation modulates Wnt3a activity by regulating LRP5 protein gradients. Thus, the secretion of VLK by projecting neurons provides crucial signals for the accurate formation of nervous system circuitry. The dramatic effect of VLK on RGMb and Wnt3a signaling implies that extracellular phosphorylation likely has broad and profound effects on brain development, function and disease.


Assuntos
Orientação de Axônios , Axônios/metabolismo , Animais , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Fosforilação
10.
J Environ Manage ; 292: 112822, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030017

RESUMO

Estimating the composition of construction waste is crucial to the efficient operation of various waste management facilities, such as landfills, public fills, and sorting plants. However, this estimating task is often challenged by the desire of quickness and accuracy in real-life scenarios. By harnessing a valuable data set in Hong Kong, this research develops a big data-probability (BD-P) model to estimate construction waste composition based on bulk density. Using a saturated data set of 4.27 million truckloads of construction waste, the probability distribution of construction waste bulk density is derived, and then, based on the Law of Joint Probability, the BD-P model is developed. A validation experiment using 604 ground truth data entries indicates a model accuracy of 90.2%, Area Under Curve (AUC) of 0.8775, and speed of around 52 s per load in estimating the composition of each incoming construction waste load. The BD-P model also informed a linear model which can perform the estimation with an accuracy of 88.8% but consuming 0.4 s per case. The major novelty of this research is to harmonize big data analytics and traditional probability theories in improving the classic challenge of predictive analyses. In the practical sphere, it satisfactorily solves the construction waste estimation problem faced by many waste management facility operators. In the academic sphere, this research provides a vivid example that big data and theories are not adversaries, but allies.


Assuntos
Materiais de Construção , Gerenciamento de Resíduos , Big Data , Hong Kong , Probabilidade , Instalações de Eliminação de Resíduos
11.
J Environ Manage ; 286: 112233, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33684803

RESUMO

There are various scenarios challenging human experts to judge the interior of something based on limited surface information. Likewise, at waste disposal facilities around the world, human inspectors are often challenged to gauge the composition of waste bulks to determine admissibility and chargeable levy. Manual approaches are laborious, hazardous, and prone to carelessness and fatigue, making unattended gauging of construction waste composition using simple surface information highly desired. This research attempts to contribute to automated waste composition gauging by harnessing a valuable dataset from Hong Kong. Firstly, visual features, called visual inert probability (VIP), characterizing inert and non-inert materials are extracted from 1127 photos of waste bulks using a fine-tuned convolutional neural network (CNN). Then, these visual features together with easy-to-obtain physical features (e.g., weight and depth) are fed to a tailor-made support vector machine (SVM) model to determine waste composition as measured by the proportions of inert and non-inert materials. The visual-physical feature hybrid model achieved a waste composition gauging accuracy of 94% in the experiments. This high performance implies that the model, with proper adaption and integration, could replace human inspectors to smooth the operation of the waste disposal facilities.


Assuntos
Instalações de Eliminação de Resíduos , Gerenciamento de Resíduos , Materiais de Construção , Hong Kong , Humanos , Modelos Teóricos , Redes Neurais de Computação , Máquina de Vetores de Suporte
12.
Molecules ; 26(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578967

RESUMO

This study evaluated the anti-ascites effect of total diterpenoids extracted from Euphorbiae Ebracteolatae Radix (TDEE) on malignant ascitic mice and elucidated its underlying mechanism. TDEE was extracted by dichloromethane and subjected to column chromatography. The purity of six diterpenoids isolated from TDEE was determined to be 77.18% by HPLC. TDEE (3 and 0.6 g raw herbs/kg, p.o.) reduced ascites and increased urine output. Meanwhile, analysis of tumor cell viability, cycle and apoptosis indicated that TDEE had no antitumor activity. In addition, the expression levels of aquaporins (AQPs) and the membrane translocation levels of protein kinase C (PKC) α and PKCß in kidney and cells were measured. TDEE reduced the levels of AQP1-4, and inhibited PKCß expression in membrane fraction. Four main diterpenoids, except compound 2, reduced AQP1 level in human kidney-2 cells. Compounds 4 and 5 inhibited AQP2-4 expression in murine inner medullary collecting duct cells. The diterpenoid-induced inhibition of AQP1-4 expression was blocked by phorbol-12-myristate-13-acetate (PMA; agonist of PKC). The diterpenoids from TDEE are the main anti-ascites components. The anti-ascites effect of diterpenoids may be associated with alterations in AQPs in the kidneys to promote diuresis. The inhibition of AQP1-4 expression by TDEE is related to the inhibition of PKCß activation.


Assuntos
Aquaporinas/metabolismo , Ascite/tratamento farmacológico , Diterpenos/farmacologia , Euphorbia/química , Rim/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Proteína Quinase C/antagonistas & inibidores , Animais , Apoptose , Aquaporinas/genética , Ascite/metabolismo , Ascite/patologia , Carcinoma Hepatocelular , Proliferação de Células , Regulação da Expressão Gênica , Humanos , Rim/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Zhongguo Zhong Yao Za Zhi ; 46(22): 5912-5921, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-34951182

RESUMO

This study investigated the material basis and mechanism of Pinelliae Rhizoma Decoction in the treatment of airway inflammation. The cigarette smoke combined with lipopolysaccharide(LPS) was used to induce an airway inflammation model in mice. The expression levels of IL-6 and IL-8 in the bronchoalveolar lavage fluid(BALF) and the phosphorylation levels of p38 and IκB in the lungs of mice were taken as indexes to screen the effective extracts by system solvent extraction from Pinelliae Rhizoma Decoction(dichloromethane extract, ethyl acetate extract, n-butanol extract, etc.). Meanwhile, the human bronchial epithelial(16-HBE) cell model of cigarette smoke extract(CSE)-induced injury was established, and the mRNA expression levels of IL-6 and IL-8 and the phosphorylation levels of p38 and IκB proteins were also taken as indexes to evaluate the anti-inflammatory effect of different extracts of Pinelliae Rhizoma Decoction. The results showed that Pinelliae Rhizoma Decoction significantly antagonized airway inflammation in mice by down-regulating the expression levels of IL-6 and IL-8 in mice with airway inflammation and 16-HBE cells with CSE-induced injury and inhibiting the phosphorylation levels of p38 and IκB. The dichloromethane and ethyl acetate extracts of Pinelliae Rhizoma Decoction showed significant anti-inflammatory effects, while such effects of other extracts were not prominent. Furthermore, the database of Pinelliae Rhizoma composition was constructed, and the components in effective extracts were analyzed by HPLC-TOF-MS and Nano-LC-MS/MS. As revealed by the results, the compositions of the two effective extracts were similar with 36 common components. They were combined and then divided into Pinelliae Rhizoma alkaloids(PTAs) and Pinelliae Rhizoma non-alkaloids(PTNAs) by 732 cation-exchange resin. Further in vitro investigation confirmed the significant anti-inflammatory effect of PTNAs, while such effect of PTAs was not manifest. The MS analysis showed 172 peptides and 7 organic acids in PTNAs. The peptide content in PTNAs was 63.5% measured by quantitative analysis of BCA assay, and the organic acid content was 9.92% by potentiometric titration method. The findings of this study suggested that Pinelliae Rhizoma Decoction could antagonize airway inflammation in mice by inhibiting phosphorylation of p38 and IκB and blocking the activation of MAPK and NF-κB signaling pathways, and the effective components were related to the peptides and organic acids in PTNAs. The above results lay a foundation for the research on the mechanism and material basis of Pinelliae Rhizoma in antagonizing airway inflammation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inflamação/tratamento farmacológico , Pinellia , Doenças Respiratórias/tratamento farmacológico , Animais , Camundongos , NF-kappa B/genética , Pinellia/química , Rizoma , Espectrometria de Massas em Tandem
14.
J Physiol ; 598(13): 2757-2773, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32347541

RESUMO

KEY POINTS: The hypothalamic-pituitary-adrenal (HPA) axis habituates to repeated stress exposure. We studied hypothalamic corticotropin-releasing hormone (CRH) neurons that form the apex of the HPA axis in a mouse model of stress habituation using repeated restraint. The intrinsic excitability of CRH neurons decreased after repeated stress in a time course that coincided with the development of HPA axis habituation. This intrinsic excitability plasticity co-developed with an expansion of surface membrane area, which increased a passive electric load and dampened membrane depolarization in response to the influx of positive charge. We report a novel structure-function relationship for intrinsic excitability plasticity as a neural correlate for HPA axis habituation. ABSTRACT: Encountering a stressor immediately activates the hypothalamic-pituitary-adrenal (HPA) axis, but this stereotypic stress response also undergoes experience-dependent adaptation. Despite the biological and clinical importance, how the brain adjusts stress responsiveness in the long term remains poorly understood. We studied hypothalamic corticotropin-releasing hormone neurons that form the apex of the HPA axis in a mouse model of stress habituation using repeated restraint. Using patch-clamp electrophysiology in acute slices, we found that the intrinsic excitability of these neurons substantially decreased after daily repeated stress in a time course that coincided with their loss of stress responsiveness in vivo. This intrinsic excitability plasticity co-developed with an expansion of surface membrane area, which increased a passive electric load, and dampened membrane depolarization in response to the influx of positive charge. Multiphoton imaging and electron microscopy revealed that repeated stress augmented ruffling of the plasma membrane, suggesting an ultrastructural plasticity that may efficiently accommodate the membrane area expansion. Overall, we report a novel structure-function relationship for intrinsic excitability plasticity as a neural correlate for adaptation of the neuroendocrine stress response.


Assuntos
Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Animais , Corticosterona , Hormônio Liberador da Corticotropina/metabolismo , Hipertrofia , Sistema Hipotálamo-Hipofisário/metabolismo , Camundongos , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Estresse Fisiológico , Estresse Psicológico
15.
Bioorg Chem ; 105: 104400, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33128966

RESUMO

The rise of drug-resistance has made the deserted clinical requirement to improve of new classes of antibiotics agents. The development of antibacterial agents with the novel method of activity stays a high need worldwide. The treatment of bacterial infections remains a test in light of developing irresistible sicknesses and the expanding number of multidrug-resistance microbial pathogens. Therefore, there is a need for powerful activities to think of new successful therapeutic agents, and it is dire to find novel synthetic analogs against bacterial targets. The improvements of new, less harmful, minimum side-effort, and extremely dynamic sulfonyl or sulfonamide-bearing analogs are hot research topics in medicinal chemistry. This present review summarizes the current innovations of sulfonyl or sulfonamide-based derivatives with potential antibacterial activities against various Gram-positive and Gram-negative bacterial strains and discussing its various aspects of structure-activity relationship (SAR).


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Sulfonamidas/farmacologia , Sulfonas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Compostos Heterocíclicos/química , Testes de Sensibilidade Microbiana , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonas/síntese química , Sulfonas/química
16.
Neuropathology ; 40(1): 104-108, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31828823

RESUMO

Nemaline myopathy (NEM) is a congenital myopathy that typically presents with proximal muscle weakness and hypotonia. To date, 13 genes have been associated with NEM. The Kelch repeat and BTB domain-containing protein 13 (KBTBD13) gene (KBTBD13)-related NEM is a rarely reported condition, and not a single case has been reported in Asia. Here, we report the case of a mother and daughter in China with NEM caused by a mutation (c.1222C>T) in KBTBD13. Their shared clinical phenotype is symmetrical muscle weakness in the arms and legs with childhood onset. Muscle magnetic resonance imaging showed the unique replacement mode of muscle with fibro-fatty tissue. Histopathological examination revealed the presence of fibers containing rod-shaped structures in the cytoplasm or under the sarcolemma. DNA sequencing analysis detected a heterozygous mutation (c.1222C>T) in KBTBD13 in this family. A founder effect for the variant may exist in the Low Countries of Belgium and the Netherlands, and the mutation may be a hotspot mutation in Europe, as it has not been reported in Asia. Our case study expands the spectrum of KBTBD13-related NEM.


Assuntos
Proteínas Musculares/genética , Mutação/genética , Miopatias da Nemalina/diagnóstico por imagem , Miopatias da Nemalina/genética , China , Feminino , Humanos , Pessoa de Meia-Idade , Linhagem
17.
Fish Physiol Biochem ; 46(5): 1743-1757, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32514853

RESUMO

Gonadotropin-releasing hormone (GnRH) is a key neuropeptide of the reproductive system. However, little is known about the role of GnRH in the spotted scat (Scatophagus argus). Here, three GnRH subtypes (cGnRH-II, sGnRH, and sbGnRH) were identified in the spotted scat. cGnRH-II and sGnRH were only expressed in the brains and gonads of both male and female fish, exhibiting a tissue-specific expression pattern, while sbGnRH was expressed at different transcription levels in all examined tissues. During ovarian maturation, hypothalamus-associated sbGnRH was upregulated, while the expression of sGnRH was variable and cGnRH-II first increased and then decreased. In vivo experiments showed that sbGnRH significantly promoted the expression of fsh and lh genes in a dose-dependent manner and exhibited a desensitization effect on lh expression at high concentrations. For sGnRH and cGnRH-II, only high concentrations could induce fsh and lh expression. Furthermore, treatment with highly concentrated sbGnRH peptide also induced fsh and lh expression, whereas the sGnRH and cGnRH-II peptides only induced fsh expression in vitro. 17ß-Estradiol (E2) significantly inhibited the expression of sbGnRH mRNA in a dose-dependent manner and did not impact sGnRH and cGnRH-II mRNA levels in vivo or in vitro. The inhibitory effect of E2 on sbGnRH expression was attenuated by the estrogen receptor (ER) broad-spectrum antagonist (fulvestrant) and the ERα-specific antagonist (methyl-piperidinopyrazole), respectively, implying that the feedback regulation on sbGnRH is mediated via ERα. This study provides a theoretical basis for the reproductive endocrinology of the spotted scat by studying GnRH.


Assuntos
Estrogênios/metabolismo , Peixes/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar , Estradiol , Feminino , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/genética , Hipotálamo , Hormônio Luteinizante/metabolismo , Ovário/crescimento & desenvolvimento , Filogenia , Receptores de Estrogênio/antagonistas & inibidores , Transcriptoma/efeitos dos fármacos
18.
Acta Pharmacol Sin ; 40(2): 279-287, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29872134

RESUMO

Mucolipidosis II α/ß, mucolipidosis III α/ß, and mucolipidosis III γ are autosomal recessive disorders belonging to the family of lysosomal storage disorders caused by deficiency of the UDP-N-acetylglucosamine, a lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase) localized in the Golgi apparatus, which is essential for normal processing and packaging of soluble lysosomal enzymes with initiating the first step of tagging lysosomal enzymes with mannose-6-phosphate (M6P). Mucolipidosis II and III are caused by mutations in the GNPTAB and GNPTG genes, and patients with these diseases are characterized by short stature, skeletal abnormalities, and developmental delay. In this study we report 38 patients with mucolipidosis II and III enrolled in Eastern China during the past 8 years. The diagnosis was made based on clinical characteristics and measurement of plasma lysosomal enzyme activity. Sanger sequencing of GNPTAB and/or GNPTG for all patients and real-time quantitative PCR were performed to confirm the diagnosis. In addition, 11 cases of prenatal mucolipidosis II were diagnosed based on measurement of the enzyme activity in amniotic fluid supernatant and genetic testing of cultured amniotic cells. Based on molecular genetic tests, 30 patients were diagnosed with mucolipidosis II α/ß, 6 were diagnosed with III α/ß and 2 were diagnosed with III γ. Thirty-seven different GNPTAB gene mutations were identified in 29 patients with mucolipidosis II α/ß and six patients with III α/ß. These mutations included 22 new mutations (p.W44X, p.E279X, p.W416X, p.W463X, p.Q802X, p.Q882X, p.A34P, p.R334P, p.D408N, p.D534N, p.Y997C, p.D1018V, p.L1025S, p.L1033P, c.88_89delAC, c.890_891insT, c.1150_1151insTTA, c.1523delG, c.2473_2474insA, c.2980_2983delGCCT, c.3094delA, and deletion of exon 9). Four new GNPTG gene mutations were identified (c.13delC, p.Y81X, p.G126R and c.609+1delG) in two mucolipidosis III γ patients. Among the 11 cases of prenatal diagnosis, four were mucolipidosis II fetuses, three were heterozygous, and the remaining four were normal fetuses. This study expands the mutation spectrum of the GNPTAB and GNPTG genes and contributes to specific knowledge of mucolipidosis II/III in a population from Eastern China.


Assuntos
Mucolipidoses/diagnóstico , Mucolipidoses/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Adolescente , Povo Asiático , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mucolipidoses/classificação , Mutação de Sentido Incorreto , Gravidez , Diagnóstico Pré-Natal
19.
Fish Physiol Biochem ; 45(6): 1963-1980, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31399918

RESUMO

Scatophagus argus is a new emerging aquaculture fish in East and Southeast Asia. To date, research on reproductive development and regulation in S. argus is lacking. Additionally, genetic and genomic information about reproduction, such as gonadal transcriptome data, is also lacking. Herein, we report the first gonadal transcriptomes of S. argus and identify genes potentially involved in reproduction and gonadal development. A total of 136,561 unigenes were obtained by sequencing of testes (n = 3) and ovaries (n = 3) at stage III. Genes upregulated in males and females known to be involved in gonadal development and gametogenesis were identified, including male-biased dmrt1, amh, gsdf, wt1a, sox9b, and nanos2, and female-biased foxl2, gdf9, bmp15, sox3, zar1, and figla. Serum estradiol-17ß and 11-ketotestosterone levels were biased in female and male fish, respectively. Sexual dimorphism of serum steroid hormone levels were interpreted after expression analysis of 20 steroidogenesis-related genes, including cyp19a1a and cyp11b2. This gonadal transcript dataset will help investigate functional genes related to reproduction in S. argus.


Assuntos
Peixes/genética , Gônadas/fisiologia , Caracteres Sexuais , Transcriptoma , Animais , Feminino , Hormônios Esteroides Gonadais/sangue , Masculino , RNA-Seq
20.
J Cell Mol Med ; 22(11): 5477-5485, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30133116

RESUMO

Recently, it was reported that long non-coding RNAs (lncRNAs) participated in promoting hepatocellular carcinoma (HCC) initiation and progression. Herein, we reported that the expression level of LINC01287 was elevated in HCC cell lines and tissues. LINC01287 down-regulation inhibited HCC cells growth and invasion both in vitro and in vivo. LINC01287 exerted as a ceRNA and negatively regulated miR-298 expression. MYB was identified as a downstream target of miR-298. The miR-298/MYB axis mediated LINC01287's effect on HCC. To the best of our knowledge, our findings provided the first evidence that LINC01287 functioned as an oncogene in HCC. LINC01287 may be a candidate prognostic biomarker and a target for new therapies in HCC patients.


Assuntos
Carcinoma Hepatocelular/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-myb/genética , RNA Longo não Codificante/genética , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Xenoenxertos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
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