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1.
Nat Rev Cardiol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499868

RESUMO

The adult heart is a complex, multicellular organ that is subjected to a series of regulatory stimuli and circuits and has poor reparative potential. Despite progress in our understanding of disease mechanisms and in the quality of health care, ischaemic heart disease remains the leading cause of death globally, owing to adverse cardiac remodelling, leading to ischaemic cardiomyopathy and heart failure. Therapeutic targets are urgently required for the protection and repair of the ischaemic heart. Moreover, personalized clinical biomarkers are necessary for clinical diagnosis, medical management and to inform the individual response to treatment. Non-coding RNAs (ncRNAs) deeply influence cardiovascular functions and contribute to communication between cells in the cardiac microenvironment and between the heart and other organs. As such, ncRNAs are candidates for translation into clinical practice. However, ncRNA biology has not yet been completely deciphered, given that classes and modes of action have emerged only in the past 5 years. In this Review, we discuss the latest discoveries from basic research on ncRNAs and highlight both the clinical value and the challenges underscoring the translation of these molecules as biomarkers and therapeutic regulators of the processes contributing to the initiation, progression and potentially the prevention or resolution of ischaemic heart disease and heart failure.

2.
Int J Health Sci (Qassim) ; 17(3): 33-38, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151747

RESUMO

Objective: Urinary bladder cancer (UBC) is the fourth most common cancer among men and tenth most common cancer in women. This study investigated an association of interleukins -17A promoter region single nucleotide polymorphism (SNP)-rs2275913 with UBC in Pakistani population. Methods: Population-based study was designed with 127 UBC patients and 100 healthy individuals. Only UBC Patients were included and other diseases hepatitis or any other malignancy/cancer were excluded from the study. Polymerase chain reaction Restriction fragment length polymorphism technique was used to genotype the rs2275913 SNP in patients and control. Linear regression analysis was performed on the genotype data and allelic frequency data. Online statistical tool was used to calculate ratio of odds. Results: Linear regression analysis showed that there was no association between rs2275913 SNP and UBC patients in the dominant model (OR = 0.815, CI = 0.415-1.6), recessive model (OR = 0.389, CI = 0.014-5.565), codominant model (OR = 0.376, CI=0.013-5.420) and (OR = 0.855, CI = 0.427-1.713). Moreover, among the UBC samples, low-grade non-muscle invasive UBC samples dominant model (OR = 0.722, CI = 0.316-1.637), recessive model (OR = 0.000, CI = 0.000-5.864), codominant model (OR = 0.864, CI = 0.030-12.668), and (OR = 0.788, CI = 0.341-1.806) did also not show any association. When same analysis was performed for high-grade muscle invasive UBC, dominant (OR = 0.936, CI = 0.403-2.155), recessive model (OR = 0.875, CI = 0.031-12.696), and codominant model (OR = 0.864, CI = 0.030-12.668,), and (OR = 0.942, CI = 0.394-2.232) did not show any association. Conclusion: Results revealed that rs2275913 did not show any associated with the high risk of UBC in Pakistani population. Some limitations of the studies are firstly, the samples size and other are detailed information on UBC and role of inflammation.

3.
J Ayub Med Coll Abbottabad ; 35(1): 60-63, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36849378

RESUMO

BACKGROUND: Chronic kidney disease (CKD) and non-alcoholic fatty liver disease (NAFLD) are becoming a health concern, owing to their increasing incidence and prevalence. Both entities are linked to poor outcomes and increased costs, hence greatly impacting the healthcare system and economy. Therefore, it is imperative to establish the link between the two, so as to prevent disease progression and complications. METHODS: The study was an observational retrospective study done in Karachi, from November 2021 to May 2022. It was conducted on 255 patients who were diagnosed with NAFLD, and the presence of CKD was then determined by calculating their GFRs. RESULTS: Out of the 255 patients diagnosed with hepatosteatosis, 76% had a normal GFR, 20% had a mild decrease and 4% were noted to have a moderate reduction in their GFR. When cross-tabulated with CAP score, it was found that 28% had S1 grade steatosis, out of which 85% had a normal GFR, 13% had a mild decrease and 2% had a moderate decrease in GFR. 22% had S2 grade steatosis, out of which 76% had a normal GFR, 18% had a mild decrease and 6% had a moderate reduction in GFR. 50% patients had S3 grade steatosis, out of which 70% had a normal GFR, 25% had a mild decrease and 5% had a moderate reduction in GFR. CONCLUSIONS: There is an association present between NAFLD and the development of low GFR. Therefore, it is important that patients diagnosed with NAFLD are regularly screened for CKD, so as to prevent its development and complications.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Insuficiência Renal Crônica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Estudos Retrospectivos , Progressão da Doença , Insuficiência Renal Crônica/epidemiologia
4.
Cells ; 11(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36496981

RESUMO

Bicuspid aortic valve (BAV) patients develop ascending aortic (AAo) dilation. The pathogenesis of BAV aortopathy (genetic vs. haemodynamic) remains unclear. This study aims to identify regional changes around the AAo wall in BAV patients with aortopathy, integrating molecular data and clinical imaging. BAV patients with aortopathy (n = 15) were prospectively recruited to surgically collect aortic tissue and measure molecular markers across the AAo circumference. Dilated (anterior/right) vs. non-dilated (posterior/left) circumferential segments were profiled for whole-genomic microRNAs (next-generation RNA sequencing, miRCURY LNA PCR), protein content (tandem mass spectrometry), and elastin fragmentation and degeneration (histomorphometric analysis). Integrated bioinformatic analyses of RNA sequencing and proteomic datasets identified five microRNAs (miR-128-3p, miR-210-3p, miR-150-5p, miR-199b-5p, and miR-21-5p) differentially expressed across the AAo circumference. Among them, three miRNAs (miR-128-3p, miR-150-5p, and miR-199b-5p) were predicted to have an effect on eight common target genes, whose expression was dysregulated, according to proteomic analyses, and involved in the vascular-endothelial growth-factor signalling, Hippo signalling, and arachidonic acid pathways. Decreased elastic fibre levels and elastic layer thickness were observed in the dilated segments. Additionally, in a subset of patients n = 6/15, a four-dimensional cardiac magnetic resonance (CMR) scan was performed. Interestingly, an increase in wall shear stress (WSS) was observed at the anterior/right wall segments, concomitantly with the differentially expressed miRNAs and decreased elastic fibres. This study identified new miRNAs involved in the BAV aortic wall and revealed the concomitant expressional dysregulation of miRNAs, proteins, and elastic fibres on the anterior/right wall in dilated BAV patients, corresponding to regions of elevated WSS.


Assuntos
Doenças da Aorta , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , MicroRNAs , Humanos , Doença da Válvula Aórtica Bicúspide/complicações , Doença da Válvula Aórtica Bicúspide/metabolismo , Doença da Válvula Aórtica Bicúspide/patologia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/complicações , Valva Aórtica/patologia , Proteômica , Doenças da Aorta/metabolismo , Imageamento por Ressonância Magnética , MicroRNAs/genética , MicroRNAs/metabolismo
5.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36209413

RESUMO

MOTIVATION: Single-cell/nuclei RNA-sequencing (scRNA-seq) technologies can simultaneously quantify gene expression in thousands of cells across the genome. However, the majority of the noncoding RNAs, such as microRNAs (miRNAs), cannot currently be profiled at the same scale. MiRNAs are a class of small noncoding RNAs and play an important role in gene regulation. MiRNAs originate from the processing of primary transcripts, known as primary-microRNAs (pri-miRNAs). The pri-miRNA transcripts, independent of their cognate miRNAs, can also function as long noncoding RNAs, code for micropeptides or even interact with DNA, acting like enhancers. Therefore, it is apparent that the significance of scRNA-seq pri-miRNA profiling expands beyond using pri-miRNA as proxies of mature miRNAs. However, there are no computational methods that allow profiling and quantification of pri-miRNAs at the single-cell-type resolution. RESULTS: We have developed a simple yet effective computational framework to profile pri-MiRNAs from single-cell RNA-sequencing datasets (PPMS). Based on user input, PPMS can profile pri-miRNAs at cell-type resolution. PPMS can be applied to both newly produced and publicly available datasets obtained via single cell or single-nuclei RNA-seq. It allows users to (i) investigate the distribution of pri-miRNAs across cell types and cell states and (ii) establish a relationship between the number of cells/reads sequenced and the detection of pri-miRNAs. Here, to demonstrate its efficacy, we have applied PPMS to publicly available scRNA-seq data generated from (i) individual chambers (ventricles and atria) of the human heart, (ii) human pluripotent stem cells during their differentiation into cardiomyocytes (the heart beating cells) and (iii) hiPSCs-derived cardiomyocytes infected with severe acute respiratory syndrome coronavirus 2.


Assuntos
COVID-19 , MicroRNAs , Pequeno RNA não Traduzido , Humanos , Processamento Pós-Transcricional do RNA , Regulação da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo
6.
Molecules ; 27(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35807359

RESUMO

The purpose of this study was to find the biological propensities of the vegetable plant Pleurospermum candollei by investigating its phytochemical profile and biological activities. Phytochemical analysis was done by spectroscopic methods to investigate the amount of total polyphenols, and biological evaluation was done by the different antioxidant, enzyme inhibitory (tyrosinase, α-amylase, and α-glucosidase), thrombolytic, and antibacterial activities. The highest amount of total phenolic and flavonoid contents was observed in methanolic extract (240.69 ± 2.94 mg GAE/g and 167.59 ± 3.47 mg QE/g); the fractions showed comparatively less quantity (57.02 ± 1.31 to 144.02 ± 2.11 mg GAE/g, and 48.21 ± 0.75 to 96.58 ± 2.30 mg QE/g). The effect of these bioactive contents was also related to biological activities. GCMS analysis led to the identification of bioactive compounds with different biological effects from methanolic extract (antioxidant; 55.07%, antimicrobial; 56.41%), while the identified compounds from the n-hexane fraction with antioxidant properties constituted 67.86%, and those with antimicrobial effects constituted 82.95%; however, the synergetic effect of polyphenols may also have contributed to the highest value of biological activities of methanolic extract. Molecular docking was also performed to understand the relationship of identified secondary metabolites with enzyme-inhibitory activities. The thrombolytic activity was also significant (40.18 ± 1.80 to 57.15 ± 1.10 % clot lysis) in comparison with streptokinase (78.5 ± 1.53 to 82.34 ± 1.25% clot lysis). Methanolic extract also showed good activity against Gram-positive strains of bacteria, and the highest activity was observed against Bacillus subtilis. The findings of this study will improve our knowledge of phytochemistry, and biological activities of P. candollei, which seems to be a ray of hope to design formulations of natural products for the improvement of health and prevention of chronic diseases; however, further research may address the development of novel drugs for use in pharmaceuticals.


Assuntos
Anti-Infecciosos , Apiaceae , Produtos Biológicos , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Metanol/química , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia
7.
J Mech Behav Biomed Mater ; 126: 105016, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34871959

RESUMO

The effect of neodymium (Nd+3) on ZnO thin films has been studied with varying Nd doping percentage ranging from 1 to 5 wt%. XRD graphs confirmed that Nd ions have incorporated into the ZnO lattice without any structural modification. The increase of crystallite size was observed to vary from 27.5 to 31.90 nm with the increment in Nd amount. The optical spectra exhibited transparency in the visible region. The higher transmission was possessed at 1 wt at% Nd concentration. The band gap of Nd-doped ZnO thin films showed variation with the increase in Nd dopant concentration. The increment in dielectric constant and tangent loss was observed with the increase in Nd doping. The change in DC conductivity with frequency was measured by using Jonscher's power law while AC conductivity was explained with the hopping-barrier mechanism. The effects of Nd concentration on antibacterial efficiency against four different bacterial strains Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella Pneumonia (K. Pneumonia), and Staphylococcus aureus (S. aureus) were investigated whereas antifungal activity of Nd-ZnO was done against Aspergillus fumigate by using agar disc-diffusion method. ZnO with 4 wt % Nd demonstrated the best photo-catalytic property.


Assuntos
Nanoestruturas , Óxido de Zinco , Antibacterianos/farmacologia , Escherichia coli , Staphylococcus aureus
9.
Mol Ther ; 29(7): 2239-2252, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-33744469

RESUMO

MicroRNAs (miRNAs) regulate gene expression by post-transcriptional inhibition of target genes. Proangiogenic small extracellular vesicles (sEVs; popularly identified with the name "exosomes") with a composite cargo of miRNAs are secreted by cultured stem cells and present in human biological fluids. Lipid nanoparticles (LNPs) represent an advanced platform for clinically approved delivery of RNA therapeutics. In this study, we aimed to (1) identify the miRNAs responsible for sEV-induced angiogenesis; (2) develop the prototype of bioinspired "artificial exosomes" (AEs) combining LNPs with a proangiogenic miRNA, and (3) validate the angiogenic potential of the bioinspired AEs. We previously reported that human sEVs from bone marrow (BM)-CD34+ cells and pericardial fluid (PF) are proangiogenic. Here, we have shown that sEVs secreted from saphenous vein pericytes and BM mesenchymal stem cells also promote angiogenesis. Analysis of miRNA datasets available in-house or datamined from GEO identified the let-7 family as common miRNA signature of the proangiogenic sEVs. LNPs with either hsa-let-7b-5p or cyanine 5 (Cy5)-conjugated Caenorhabditis elegans miR-39 (Cy5-cel-miR-39; control miRNA) were prepared using microfluidic micromixing. let-7b-5p-AEs did not cause toxicity and transferred functionally active let-7b-5p to recipient endothelial cells (ECs). let-7b-AEs also improved EC survival under hypoxia and angiogenesis in vitro and in vivo. Bioinspired proangiogenic AEs could be further developed into innovative nanomedicine products targeting ischemic diseases.


Assuntos
Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Lipossomos/química , MicroRNAs/metabolismo , Nanopartículas/química , Neovascularização Fisiológica , Líquido Pericárdico/fisiologia , Animais , Exossomos/genética , Vesículas Extracelulares/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Camundongos , MicroRNAs/genética
10.
Int J Mol Sci ; 21(5)2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32138369

RESUMO

MicroRNAs (miRs) regulate complex processes, including angiogenesis, by targeting multiple mRNAs. miR-24-3p-3p directly represses eNOS, GATA2, and PAK4 in endothelial cells (ECs), thus inhibiting angiogenesis during development and in the infarcted heart. miR-24-3p is widely expressed in cardiovascular cells, suggesting that it could additionally regulate angiogenesis by acting on vascular mural cells. Here, we have investigated: 1) new miR-24-3p targets; 2) the expression and the function of miR-24-3p in human vascular ECs; 3) the impact of miR-24-3p inhibition in the angiogenesis reparative response to limb ischemia in mice. Using bioinformatics target prediction platforms and 3'-UTR luciferase assays, we newly identified Notch1 and its Delta-like ligand 1 (Dll1) to be directly targeted by miR-24-3p. miR-24-3p was expressed in human ECs and pericytes cultured under normal conditions. Exposure to hypoxia increased miR-24-3p in ECs but not in pericytes. Transfection with a miR-24-3p precursor (pre-miR-24-3p) increased miR-24-3p expression in ECs, reducing the cell survival, proliferation, and angiogenic capacity. Opposite effects were caused by miR-24-3p inhibition. The anti-angiogenic action of miR-24-3p overexpression could be prevented by simultaneous adenovirus (Ad)-mediated delivery of constitutively active Notch intracellular domain (NICD) into cultured ECs. We next demonstrated that reduced Notch signalling contributes to the anti-angiogenic effect of miR-24-3p in vitro. In a mouse unilateral limb ischemia model, local miR-24-3p inhibition (by adenovirus-mediated miR-24-3p decoy delivery) restored endothelial Notch signalling and increased capillary density. However, the new vessels appeared disorganised and twisted, worsening post-ischemic blood perfusion recovery. To better understand the underpinning mechanisms, we widened the search for miR-24-3p target genes, identifying several contributors to vascular morphogenesis, such as several members of the Wingless (Wnt) signalling pathway, ß-catenin signalling components, and VE-cadherin, which synergise to regulate angiogenesis, pericytes recruitment to neoformed capillaries, maturation, and stabilization of newly formed vessels. Among those, we next focussed on ß-catenin to demonstrate that miR-24-3p inhibition reduces ß-catenin expression in hypoxic ECs, which is accompanied by reduced adhesion of pericytes to ECs. In summary, miR-24-3p differentially targets several angiogenesis modulators and contributes to autonomous and non-autonomous EC crosstalk. In ischemic limbs, miR-24-3p inhibition increases the production of dysfunctional microvessels, impairing perfusion. Caution should be observed in therapeutic targeting of miR-24-3p.


Assuntos
Isquemia/metabolismo , MicroRNAs/metabolismo , Receptores Notch/metabolismo , Regiões 3' não Traduzidas/genética , Regiões 3' não Traduzidas/fisiologia , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Extremidades/patologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isquemia/genética , Isquemia/patologia , Masculino , Camundongos , MicroRNAs/genética , Músculo Esquelético/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores Notch/genética , beta Catenina/genética , beta Catenina/metabolismo
11.
Dev Biol ; 457(1): 69-82, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539539

RESUMO

Vertebrate ear progenitors are induced by fibroblast growth factor signalling, however the molecular mechanisms leading to the coordinate activation of downstream targets are yet to be discovered. The ear, like other sensory placodes, arises from the pre-placodal region at the border of the neural plate. Using a multiplex NanoString approach, we determined the response of these progenitors to FGF signalling by examining the changes of more than 200 transcripts that define the otic and other placodes, neural crest and neural plate territories. This analysis identifies new direct and indirect FGF targets during otic induction. Investigating changes in histone marks by ChIP-seq reveals that FGF exposure of pre-placodal cells leads to rapid deposition of active chromatin marks H3K27ac near FGF-response genes, while H3K27ac is depleted in the vicinity of non-otic genes. Genomic regions that gain H3K27ac act as cis-regulatory elements controlling otic gene expression in time and space and define a unique transcription factor signature likely to control their activity. Finally, we show that in response to FGF signalling the transcription factor dimer AP1 recruits the histone acetyl transferase p300 to selected otic enhancers. Thus, during ear induction FGF signalling modifies the chromatin landscape to promote enhancer activation and chromatin accessibility.


Assuntos
Orelha/embriologia , Elementos Facilitadores Genéticos , Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Animais , Proteínas Aviárias/metabolismo , Embrião de Galinha , Fatores de Transcrição Forkhead/metabolismo , Código das Histonas , Proteínas Oncogênicas v-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
13.
Mol Ther Nucleic Acids ; 17: 49-62, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31220779

RESUMO

MicroRNA-15a (miR-15a) and miR-16, which are transcribed from the miR-15a/miR-16-1 cluster, inhibit post-ischemic angiogenesis. MicroRNA (miRNA) binding to mRNA coding sequences (CDSs) is a newly emerging mechanism of gene expression regulation. We aimed to (1) identify new mediators of the anti-angiogenic action of miR-15a and -16, (2) develop an adenovirus (Ad)-based miR-15a/16 decoy system carrying a luciferase reporter (Luc) to both sense and inhibit miR-15a/16 activity, and (3) investigate Ad.Luc-Decoy-15a/16 therapeutic potential in a mouse limb ischemia (LI) model. LI increased miR-15a and -16 expression in mouse muscular endothelial cells (ECs). The miRNAs also increased in cultured human umbilical vein ECs (HUVECs) exposed to serum starvation, but not hypoxia. Using bioinformatic tools and luciferase activity assays, we characterized miR-15a and -16 binding to Tie2 CDS. In HUVECs, miR-15a or -16 overexpression reduced Tie2 at the protein, but not the mRNA, level. Conversely, miR-15a or -16 inhibition improved angiogenesis in a Tie2-dependent manner. Local Ad.Luc-Decoy-15a/16 delivery increased Tie2 levels in ischemic skeletal muscle and improved post-LI angiogenesis and perfusion recovery, with reduced toe necrosis. Bioluminescent imaging (in vivo imaging system [IVIS]) provided evidence that the Ad.Luc-Decoy-15a/16 system responds to miR-15a/16 increases. In conclusion, we have provided novel mechanistic evidence of the therapeutic potential of local miR-15a/16 inhibition in LI.

14.
PLoS One ; 14(3): e0213685, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30870483

RESUMO

This study aimed to optimise techniques for whole transcriptome and small RNA analyses on clinical tissue samples from patients with cardiovascular disease. Clinical samples often represent a particular challenge to extracting RNA of sufficient quality for robust RNA sequencing analysis, and due to availability, it is rarely possible to optimise techniques on the samples themselves. Therefore, we have used equivalent samples from pigs undergoing cardiopulmonary bypass surgery to test different protocols for optimal RNA extraction, and then validated the protocols in human samples. Here we present an assessment of the quality and quantity of RNA obtained using a variety of commercially-available RNA extraction kits on both left ventricular biopsies and blood plasma. RNA extraction from these samples presents different difficulties; left ventricular biopsies are small and fibrous, while blood plasma has a low RNA content. We have validated our optimised extraction techniques on human clinical samples collected as part of the ARCADIA (Association of non-coding RNAs with Coronary Artery Disease and type 2 Diabetes) cohort study, resulting in successful whole transcriptome and small RNA sequencing of human left ventricular tissue.


Assuntos
Biópsia/métodos , Perfilação da Expressão Gênica/métodos , Ventrículos do Coração/patologia , RNA/análise , Transcriptoma , Adulto , Idoso , Animais , Ponte Cardiopulmonar , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Eletroforese Capilar , Feminino , Ventrículos do Coração/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Estudos Prospectivos , Controle de Qualidade , Análise de Sequência de RNA , Suínos
15.
Colloids Surf B Biointerfaces ; 171: 383-390, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30059854

RESUMO

The role of Ag dopant on ZnO thin films are studied. Ag doped ZnO thin films were deposited by sol-gel dip coating on glass substrates. The X-ray diffraction analysis shows hexagonal wurtzite with preferred orientation along the (101) plane. The crystallite size decreases from 33.40 nm to 28.37 nm with increase in silver doping percentage. Optical examination shows that the band gap decrease with an increase in the Ag doping in ZnO. The structural and optical results prove that Ag has substituted Zn in ZnO lattice. Silver doped ZnO is effective against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) bacteria. The roughness and the surface oxygen species accelerate the bacteria killing properties of Ag doped ZnO. They have pharmacological utility as a replacement of the antibiotics, bactericide and disinfectants. The TGA study showed that the thermal stability of the Ag doped ZnO takes place between 380-435 °C.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Óxido de Zinco/farmacologia , Antibacterianos/química , Géis/química , Géis/farmacologia , Testes de Sensibilidade Microbiana , Fenômenos Ópticos , Tamanho da Partícula , Prata/química , Propriedades de Superfície , Óxido de Zinco/química
16.
Bioinformatics ; 34(5): 890-892, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28961702

RESUMO

Summary: MWASTools is an R package designed to provide an integrated pipeline to analyse metabonomic data in large-scale epidemiological studies. Key functionalities of our package include: quality control analysis; metabolome-wide association analysis using various models (partial correlations, generalized linear models); visualization of statistical outcomes; metabolite assignment using statistical total correlation spectroscopy (STOCSY); and biological interpretation of metabolome-wide association studies results. Availability and implementation: The MWASTools R package is implemented in R (version > =3.4) and is available from Bioconductor: https://bioconductor.org/packages/MWASTools/. Contact: m.dumas@imperial.ac.uk. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Metaboloma , Metabolômica/métodos , Software , Estudos de Associação Genética , Humanos , Metabolômica/normas , Modelos Biológicos , Controle de Qualidade
17.
Sci Rep ; 7(1): 6162, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28733657

RESUMO

During development cell commitment is regulated by inductive signals that are tightly controlled in time and space. In response, cells activate specific programmes, but the transcriptional circuits that maintain cell identity in a changing signalling environment are often poorly understood. Specification of inner ear progenitors is initiated by FGF signalling. Here, we establish the genetic hierarchy downstream of FGF by systematic analysis of many ear factors combined with a network inference approach. We show that FGF rapidly activates a small circuit of transcription factors forming positive feedback loops to stabilise otic progenitor identity. Our predictive network suggests that subsequently, transcriptional repressors ensure the transition of progenitors to mature otic cells, while simultaneously repressing alternative fates. Thus, we reveal the regulatory logic that initiates ear formation and highlight the hierarchical organisation of the otic gene network.


Assuntos
Orelha Interna/crescimento & desenvolvimento , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica/veterinária , Redes Reguladoras de Genes , Animais , Embrião de Galinha , Orelha Interna/química , Retroalimentação Fisiológica , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais , Fatores de Transcrição/genética
18.
Development ; 144(15): 2810-2823, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28684624

RESUMO

In vertebrates, cranial placodes contribute to all sense organs and sensory ganglia and arise from a common pool of Six1/Eya2+ progenitors. Here we dissect the events that specify ectodermal cells as placode progenitors using newly identified genes upstream of the Six/Eya complex. We show in chick that two different tissues, namely the lateral head mesoderm and the prechordal mesendoderm, gradually induce placode progenitors: cells pass through successive transcriptional states, each identified by distinct factors and controlled by different signals. Both tissues initiate a common transcriptional state but over time impart regional character, with the acquisition of anterior identity dependent on Shh signalling. Using a network inference approach we predict the regulatory relationships among newly identified transcription factors and verify predicted links in knockdown experiments. Based on this analysis we propose a new model for placode progenitor induction, in which the initial induction of a generic transcriptional state precedes regional divergence.


Assuntos
Transdução de Sinais/fisiologia , Vertebrados/embriologia , Animais , Comunicação Celular/genética , Comunicação Celular/fisiologia , Embrião de Galinha , Galinhas , Ectoderma/citologia , Ectoderma/embriologia , Ectoderma/metabolismo , Eletroporação , Gânglios Sensitivos/citologia , Gânglios Sensitivos/embriologia , Gânglios Sensitivos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hibridização In Situ , Análise de Sequência com Séries de Oligonucleotídeos , Codorniz , Órgãos dos Sentidos/citologia , Órgãos dos Sentidos/embriologia , Órgãos dos Sentidos/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Vertebrados/metabolismo
19.
Genesis ; 51(5): 296-310, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23174848

RESUMO

Setting up the body plan during embryonic development requires the coordinated action of many signals and transcriptional regulators in a precise temporal sequence and spatial pattern. The last decades have seen an explosion of information describing the molecular control of many developmental processes. The next challenge is to integrate this information into logic "wiring diagrams" that visualize gene actions and outputs, have predictive power and point to key control nodes. Here, we provide an experimental workflow on how to construct gene regulatory networks using the chick as model system.


Assuntos
Galinhas/genética , Redes Reguladoras de Genes , Animais , Embrião de Galinha , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica
20.
Bioinformation ; 6(8): 293-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21769188

RESUMO

Acquisition of new genetic material through horizontal gene transfer has been shown to be an important feature in the evolution of many pathogenic bacteria. Changes in the genetic repertoire, occurring through gene acquisition and deletion, are the major events underlying the emergence and evolution of bacterial pathogens. However, horizontal gene transfer across the domains i.e. archaea and bacteria is not so common. In this context, we explore events of horizontal gene transfer between archaea and bacteria. In order to determine whether the acquisition of archaeal genes by lateral gene transfer is an important feature in the evolutionary history of the pathogenic bacteria, we have developed a scheme of stepwise eliminations that identifies archaeal-like genes in various bacterial genomes. We report the presence of 9 genes of archaeal origin in the genomes of various bacteria, a subset of which is also unique to the pathogenic members and are not found in respective non-pathogenic counterparts. We believe that these genes, having been retained in the respective genomes through selective advantage, have key functions in the organism's biology and may play a role in pathogenesis.

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