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1.
Artigo em Inglês | MEDLINE | ID: mdl-33129971

RESUMO

BACKGROUND: Left-sided ablation, targeting left inferior AV nodal extensions, is thought to be necessary for success in a small proportion of atrioventricular nodal re-entrant tachycardia (AVNRT) ablations; however Indian data are scarce in this regard. METHODS: Consecutive cases of AVNRT undergoing slow pathway ablation in a single centre over an 18-month period were retrospectively analyzed. Left-sided ablation at the posteroseptal mitral annulus was performed if right-sided ablation failed to abolish AVNRT. RESULTS: From January 2017 to June 2018, out of 215 consecutive supraventricular tachycardia (SVT) cases, 154 (71.6%) were AVNRT (47.1 ± 13.1 years, 46.1% male). Trans-septal ablation was required in 5 (3.2%) cases (mean age 48.8 ± 9.4 years; 4 female, 1 male); all with typical (slow-fast) form of AVNRT. Compared with cases needing only right-sided ablation, radiofrequency time (50.8 ± 16.9 vs. 9.9 ± 8.5 min; p = 0.005) and procedure time (166.0 ± 35.0 vs 79.6 ± 35.9 min; p = 0.004) were significantly longer for trans-septal cases, while baseline intervals and tachycardia cycle length were not significantly different. Junctional ectopy was seen in only 2 of the 5 cases during left-sided ablation, but acute success (non-inducibility) was obtained in 3 cases. There were no instances of AV block. Over mean follow-up of 12.2 ± 4.0 months, clinical recurrence of AVNRT occurred in one case, while others remained arrhythmia-free without medication. CONCLUSION: Left-sided ablation was required in a small proportion of AVNRT ablations. Trans-septal approach targeting the posteroseptal mitral annulus was safe and yielded good mid-term clinical success.

2.
Am J Physiol Heart Circ Physiol ; 317(1): H168-H180, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31026178

RESUMO

In this study, we investigated the role of DNA methylation [5-methylcytosine (5mC)] and 5-hydroxymethylcytosine (5hmC), epigenetic modifications that regulate gene activity, in dilated cardiomyopathy (DCM). A MYBPC3 mutant mouse model of DCM was compared with wild type and used to profile genomic 5mC and 5hmC changes by Chip-seq, and gene expression levels were analyzed by RNA-seq. Both 5mC-altered genes (957) and 5hmC-altered genes (2,022) were identified in DCM hearts. Diverse gene ontology and KEGG pathways were enriched for DCM phenotypes, such as inflammation, tissue fibrosis, cell death, cardiac remodeling, cardiomyocyte growth, and differentiation, as well as sarcomere structure. Hierarchical clustering of mapped genes affected by 5mC and 5hmC clearly differentiated DCM from wild-type phenotype. Based on these data, we propose that genomewide 5mC and 5hmC contents may play a major role in DCM pathogenesis. NEW & NOTEWORTHY Our data demonstrate that development of dilated cardiomyopathy in mice is associated with significant epigenetic changes, specifically in intronic regions, which, when combined with gene expression profiling data, highlight key signaling pathways involved in pathological cardiac remodeling and heart contractile dysfunction.


Assuntos
Cardiomiopatia Dilatada/genética , Metilação de DNA , Epigênese Genética , Íntrons , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Proteínas de Transporte/genética , Ilhas de CpG , Redes Reguladoras de Genes , Predisposição Genética para Doença , Hidroxilação , Masculino , Camundongos Mutantes , Mutação , Fenótipo , Regiões Promotoras Genéticas , Transcriptoma , Função Ventricular Esquerda/genética
3.
Pharm Biol ; 54(4): 674-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26510692

RESUMO

CONTEXT: Thymoquinone (TQ), an active component of Nigella sativa L. (Ranunculaceae), possesses anti-inflammatory and anti-oxidative properties. Polycystic ovary syndrome exhibits chronic inflammatory behavior, thus might involve nuclear factor kappa B (NF-κB) signaling and related molecular factors. OBJECTIVE: The objective of the present study is to investigate and validate the effect of TQ in polycystic ovary (PCO) rat. MATERIALS AND METHODS: To validate the effect of TQ (1 µM/ml), NF-κB activation, COX2 (cyclooxygenase-2) expression and reactive oxygen species (ROS) induction were studied in the KK1 cell line. To evaluate the effect of TQ (2 mg/200 µl olive oil/rat; sc) with an in vivo system, ovulation rate, levels of key ovulation mediators, and ovarian gelatinases activity were compared in superovulated, PCO, and RU486 + TQ-treated Wistar rats. RESULTS: In vitro studies showed that NF-κB nuclear translocation, COX2, and ROS expression were repressed via TQ supplementation in RU486-treated KK1 cells. Pretreatment of TQ in the PCO rat model induced significant restoration of normal physio-molecular behavior of ovary, such as reduced cysts formation, increased ovulation rate, and normalization of key ovarian factors [like TNF-α-stimulated gene/protein 6, hyaluronan, hyaluronan-binding protein 1, COX2, matrix metalloproteinases (membrane type 1-matrix metalloproteinase, MMP9 and MMP2)], tissue inhibitor of metalloproteinases (TIMP-1 and TIMP-2), and gelatinases (like MMP9 and -2) activity during follicular maturation. DISCUSSION AND CONCLUSION: Overall, most of the above molecular changes are regulated via NF-κB pathway, thus TQ, due to its modulatory effect on the NF-κB signaling, could elevate normal ovarian phenotype and physiological function in the PCO model, indicating its remarkable potential as a remedy for rat PCO.


Assuntos
Benzoquinonas/uso terapêutico , Modelos Animais de Doenças , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Animais , Benzoquinonas/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Feminino , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Síndrome do Ovário Policístico/patologia , Ratos , Ratos Wistar
4.
Mol Cell Biochem ; 398(1-2): 233-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25300617

RESUMO

Proper follicular development is crucial for cumulus-oocyte complex (COC) maturation, ovulation and luteinisation. All these ovarian processes are regulated by finely tuned rapid tissue remodeling that involves hyaluronan and interconnecting hyaladherins-rich extracellular matrix synthesis and its breakdown by various proteinase systems like matrix metalloproteinase (MMP). Disrupted tissue remodeling machinery can result into pathophysiologies like atretic follicular cysts formation in polycystic ovary syndrome (PCOS). In present study, we employ superovulated (SO) and polycystic ovary (PCO) rat models and demonstrate that on contrary to SO, PCO rat ovary illustrates abnormal follicular morphology with differential levels of various ovarian factors [like HA (hyaluronan), TSG-6 (TNF-α-stimulated gene/protein 6), PTX-3 (pentraxin-3), HABP1 (hyaluronan binding protein 1), MMP2 (matrix metalloproteinase), MT1-MMP (membrane type 1-matrix metalloproteinase) and COX2 (Cyclooxygenase-2)] along with hyperactivities of gelatinases (like MMP9 and -2). Besides cultured COC expansion is blocked by anti-HABP1 antibody treatment showing reduced HABP1 expression. Overall, as MT1-MMP has inverse relation with HABP1 level and direct effect on MMP2 activity, the observations from current in vivo and in vitro studies indicate that disrupted ovarian HABP1 along with concurrent altered expression and hyperactivation of related MMPs can lead to abnormal follicular maturation resulting into ovarian dysfunction in PCO rat.


Assuntos
Proteínas Mitocondriais/metabolismo , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Superovulação/metabolismo , Animais , Western Blotting , Proteína C-Reativa/metabolismo , Moléculas de Adesão Celular/metabolismo , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Ácido Hialurônico/metabolismo , Imuno-Histoquímica , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ovário/patologia , Ratos Wistar , Componente Amiloide P Sérico/metabolismo , Fatores de Tempo
5.
Artigo em Inglês | MEDLINE | ID: mdl-38957358

RESUMO

Type 2 diabetes mellitus (T2DM) is a metabolic disease and comorbidity associated with several conditions, including cardiac dysfunction leading to heart failure with preserved ejection fraction (HFpEF), in turn resulting in T2DM-induced cardiomyopathy (T2DM-CM). However, the molecular mechanisms underlying the development of T2DM-CM are poorly understood. It is hypothesized that molecular alterations in myopathic genes induced by diabetes promote the development of HFpEF, whereas cardiac myosin inhibitors can rescue the resultant T2DM-mediated cardiomyopathy. To test this hypothesis, a Leptin receptor-deficient db/db homozygous (Lepr db/db) mouse model was used to define the pathogenesis of T2DM-CM. Echocardiographic studies at 4 and 6 months revealed that Lepr db/db hearts started developing cardiac dysfunction by four months, and left ventricular hypertrophy with diastolic dysfunction was evident at 6 months. RNA-seq data analysis, followed by functional enrichment, revealed the differential regulation of genes related to cardiac dysfunction in Lepr db/db heart tissues. Strikingly, the level of cardiac myosin binding protein-C phosphorylation was significantly increased in Lepr db/db mouse hearts. Finally, using isolated skinned papillary muscles and freshly isolated cardiomyocytes, CAMZYOS ® (mavacamten, MYK-461), a prescription heart medicine used for symptomatic obstructive hypertrophic cardiomyopathy treatment, was tested for its ability to rescue T2DM-CM. Compared with controls, MYK-461 significantly reduced force generation in papillary muscle fibers and cardiomyocyte contractility in the db/db group. This line of evidence shows that 1) T2DM-CM is associated with hyperphosphorylation of cardiac myosin binding protein-C and 2) MYK-461 significantly lessened disease progression in vitro, suggesting its promise as a treatment for HFpEF.

6.
bioRxiv ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38948714

RESUMO

BACKGROUND: Primary hypertension in childhood tracks into adulthood and may be associated with increased cardiovascular risk. Studies conducted in children and adolescents provide an opportunity to explore the early cardiovascular target organ injury (CV-TOI) in a population free from many of the comorbid cardiovascular disease risk factors that confound studies in adults. METHODS: Youths (n=132, mean age 15.8 years) were stratified by blood pressure (BP) as low, elevated, and high-BP and by left ventricular mass index (LVMI) as low- and high-LVMI. Systemic circulating RNA, miRNA, and methylation profiles in peripheral blood mononuclear cells and deep proteome profiles in serum were determined using high-throughput sequencing techniques. RESULTS: VASH1 gene expression was elevated in youths with high-BP with and without high-LVMI. VASH1 expression levels positively correlated with systolic BP (r=0.3143, p=0.0034). The expression of hsa-miR-335-5p, one of the VASH1-predicted miRNAs, was downregulated in high-BP with high-LVMI youths and was inversely correlated with systolic BP (r=-0.1891, p=0.0489). GSE1 hypermethylation, circulating PROZ upregulation (log2FC=0.61, p=0.0049 and log2FC=0.62, p=0.0064), and SOD3 downregulation (log2FC=-0.70, p=0.0042 and log2FC=-0.64, p=0.010) were observed in youths with elevated BP and high-BP with high-LVMI. Comparing the transcriptomic and proteomic profiles revealed elevated HYAL1 levels in youths displaying high-BP and high-LVMI. CONCLUSIONS: The findings are compatible with a novel blood pressure-associated mechanism that may occur through impaired angiogenesis and extracellular matrix degradation through dysregulation of Vasohibin-1 and Hyaluronidase1 was identified as a possible mediator of CV-TOI in youth with high-BP and suggests strategies for ameliorating TOI in adult-onset primary hypertension.

7.
Int Tinnitus J ; 18(1): 35-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24995898

RESUMO

INTRODUCTION: The general consensus on the roles of hearing loss in triggering tinnitus seems not applicable in patients with normal hearing thresholds. The absence of hearing loss on the audiogram in this group of patients poses a serious challenge to the cochlear theories in explaining tinnitus generation in this group of patients. OBJECTIVE: To scrutinize auditory functioning in a sample of tinnitus subjects with normal hearing thresholds and non-tinnitus normally hearing control participants using transient evoked and distortion product otoacoustic emission (TEOAE and DPOAE) and Threshold Equalising Noise (TEN) test. METHODS: Twenty-seven tinnitus adult patients with normal hearing thresholds and 27 normally hearing volunteers were tested with TEOAE, DPOAE and TEN test. RESULTS: Abnormal TEOAE was significantly more in tinnitus group than in controls. No significant difference was observed in DPOAE and TEN test. Only one patient was found with a positive TEN test result, who was confirmed by Magnetic Resonance Imaging to have acoustic neuroma on the affected ear. CONCLUSION: These results suggest the possible existence of subtle auditory deficit in normally hearing tinnitus patients, which may be an early sign of diseases that are only diagnosed after the onset of hearing loss.


Assuntos
Limiar Auditivo/fisiologia , Perda Auditiva/diagnóstico , Ruído , Emissões Otoacústicas Espontâneas/fisiologia , Mascaramento Perceptivo/fisiologia , Zumbido/diagnóstico , Zumbido/fisiopatologia , Adulto , Feminino , Perda Auditiva/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/diagnóstico , Neuroma Acústico/fisiopatologia , Valor Preditivo dos Testes
8.
Environ Technol ; 44(2): 197-210, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34380379

RESUMO

Oil interceptors are traditional SuDS devices used in highway runoff treatment to remove both floatable impurities (leaves, oil) and total suspended solids (TSS). This paper presents the results of an examination of the performance of an oil interceptor based on particle size distribution (PSD) and TSS during three rainfall events. The interceptor is situated on one of the busiest motorways in the UK (where peak traffic flow is 30,000 vehicles per hour). Although the overall data collected for this study provided evidence that the interceptor removed, in most cases, 70% of TSS, the data for particle size distribution (PSD) showed that the interceptor did not always cope with particle separation for particles of less than 25 µm diameter.


Assuntos
Chuva , Movimentos da Água , Monitoramento Ambiental/métodos
9.
Heliyon ; 9(4): e15438, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37123982

RESUMO

There is a significant increase in the literature on learning resources in Higher Education (HE) but very limited evidence of studies that have taken a global overview of the context, range, and emerging trends from the previous research. This study aims to conduct a Scientometric analysis of research articles to accommodate a global overview and research trends under the theme of learning resources in HE. 4489 scientific articles were obtained as the dataset from the Web Of Science database between 1970 and 2022. Network maps and critical data were obtained by conducting co-authorship analysis for authors, organisations and countries and co-occurrence analysis for keywords from the VOSviewer software. The study revealed that the USA had a significant research input, and Salamin, N. from the University of Lausanne was recognised as the most frequently published author. The University of Illinois, USA, has the highest contribution to research articles, and the most popular research hotspots and trends were e-learning, Education, Academic libraries, Learning resources, and Cloud computing. However, the most critical finding from the study is that there needs to be real collaboration within the research theme and suggests ways to improve collaborations to enhance learning resources in HE. This study may be the first to conduct a scientometric analysis of Learning Resources in Higher education. This study offers valuable insight to academics, academic institutions, researchers, policymakers and pedagogical statutory bodies to understand the current context of learning resources in HE and recognise further develop research, collaborations and policies by considering critical findings from the study.

10.
Environ Sci Pollut Res Int ; 30(9): 24088-24100, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36334206

RESUMO

The role of nanozinc source (nanohydrozincite: nHZ; nanozinc oxide: nZO) on the performance of alkali-activated slag (AAS) was explored for the first time in the present work. The results showed that nHZ with different contents (0.5, 1.0, and 1.5 wt%) retards the early hydration rate of AAS, whereas nZO showed the lowest retardation effect. Zn(OH)2 is the main retarder inside AAS-nZO and AAS-nHZ, which consumes the dissolved Ca2+ (responsible for the early hardening of AAS) from slag to yield calcium zincate hydrate (CZH). The high retardation rate of nHZ is originated from its high affinity to consume much Ca2+ through the formation of additional pirssonite (Na2CO3.CaCO3.2H2O) double salt. Although adding nHZ induced the drying shrinkage of AAS, it improved the later compressive strengths (28 to 365 days), especially at low nHZ content (0.5 wt%), via the formation of CASH with lower Ca/Si ratio and higher binding capacity compared to that formed inside AAS and AAS-nZO. A further research is needed to reduce the drying shrinkage and to accelerate the early strength of AAS containing nHZ.


Assuntos
Álcalis , Cálcio , Força Compressiva , Dessecação , Óxidos
11.
J Biol Chem ; 286(28): 25076-87, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21586571

RESUMO

The human transcriptional positive coactivator 4 (PC4) activates several p53-dependent genes. It has been demonstrated that this is a consequence of direct interaction with p53. Previously, we have concluded that PC4 interacts mainly with the C-terminal negative regulatory domain of p53 through its DNA binding C-terminal half. NMR chemical shift perturbation studies with peptide fragments indicated that amino acids 380-386 of p53 are crucial for interaction with PC4. This was verified by fluorescence anisotropy and sedimentation velocity studies. A peptide consisting of p53-(380-386) sequence, when attached to a cell penetration tag and nuclear localization signal, localizes to the nucleus and inhibits luciferase gene expression from a transfected plasmid carrying a Luc gene under a p53-dependent promoter. Acetylation of lysine 382/381 enhanced the binding of this peptide to PC4 by about an order of magnitude. NMR and mutagenesis studies indicated that serine 73 of PC4 is an important residue for recognition of p53. Intermolecular nuclear Overhauser effect placed aspartate 76 in the vicinity of lysine 381, indicating that the region around residues 73-76 of PC4 is important for p53 recognition. We conclude that the 380-386 region of p53 interacts with the region around residues 73-76 of PC4, and acetylation of lysine 382/381 of p53 may play an important role in modulating p53-PC4 interaction and as a consequence PC4 mediated activation of p53 target genes.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acetilação , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Humanos , Lisina/química , Lisina/genética , Lisina/metabolismo , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/genética , Sinais de Localização Nuclear/metabolismo , Ressonância Magnética Nuclear Biomolecular , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína , Fatores de Transcrição/química , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética
12.
Heart Surg Forum ; 15(5): E286-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23092668

RESUMO

A patient presented with recurrent syncope due to transient severe hypotension. The patient's history, physical examination, and initial baseline investigation did not suggest a cardiovascular cause. After fluid resuscitation, a raised jugular venous pulse was noted. Bedside transthoracic echocardiogram showed a pericardial effusion and a proximally dilated aorta. Computed tomography of the thorax confirmed these findings and also demonstrated an intramural hematoma of the proximal aortic wall.The patient was transferred to a cardiothoracic center, where he was at first treated medically. He then developed sudden cardiogenic shock due to pericardial tamponade and was successfully operated on.It is important to recognize an acute intramural hematoma of the proximal aortic wall as a cardiothoracic emergency. This condition can present atypically, but nevertheless warrants urgent surgical intervention, equal to type A aortic dissection. Echocardiography can help in making the diagnosis.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Tamponamento Cardíaco/cirurgia , Ecocardiografia Transesofagiana , Hematoma/diagnóstico , Doença Aguda , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico por imagem , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/etiologia , Serviço Hospitalar de Emergência , Seguimentos , Hematoma/etiologia , Hematoma/cirurgia , Humanos , Hipotensão/diagnóstico , Hipotensão/etiologia , Masculino , Recidiva , Medição de Risco , Síncope/diagnóstico , Síncope/etiologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
Environ Technol ; 43(11): 1732-1744, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33180680

RESUMO

Although highway runoff has historically been extensively studied, the increasing complexity of stormwater management means that there are still significant gaps regarding the reduction of soluble metals. The work reported in this paper addresses these challenges by analysing the presence and behaviour of iron, copper and zinc in runoff from junction 24 of the M1 motorway in the UK (peak traffic flow: 30,000 vehicles per hour) and comparing it with other urban sources of metals found in the same catchment (a local brook and sewage treatment works). The sampling site included an interceptor and a treatment lagoon and the event monitoring indicated a trend by which the metals did not change their concentration or particulate soluble proportion immediately, hence showing that pre- and post-storm conditions are important factors when analysing the solubility of metals and their behaviour. The data provided further evidence of the important influence of storm characteristics on metal concentrations in highway runoff, in particular the effects of an antecedent dry weather period (ADWP). In addition, this study also helped us to better understand how the release of sodium the application of de-icer for road maintenance in winter affects the availability of zinc.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cobre/análise , Poeira/análise , Monitoramento Ambiental , Metais/análise , Metais Pesados/análise , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise , Zinco/análise
14.
Environ Sci Pollut Res Int ; 29(31): 47209-47224, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35182335

RESUMO

This study represents the sustainable/safe consumption of lead glass sludge (LGS) in the fabrication of thermally insulating foamed glass via sintering (750-950º C) and chlorination processes. The impact of selected additives including calcium chloride (CaCl2) and sodium hydroxide (NaOH) on the foaming efficiency and Pb-stabilization has been deeply investigated. LGS is mainly lead silicate material with considerable content of calcium carbonate, which acts as foaming agent during sintering process. The newly developed foamed-materials exhibited thermal conductivity of 0.054-0.136 W/m.K, density of 0.23-1.10 g/cm3, porosity of 63.3-92.6%, and compressive strength of 0.10-2.69 MPa. X-ray diffraction proved that the immobilization mechanism was attributed to the transformation of free Pb within LGS into insoluble ganomalite Pb9Ca5MnSi9O33 phase. Adding NaOH enhanced the foaming process accompanied by a significant reduction in Pb-leaching. Incorporating CaCl2 has resulted in a retardation in Pb-leaching, which associated with Pb-stabilization and Pb-vaporization. In an attempt to reduce CO2-emission, the potential use of alkali-rich-wastewater (AW) as eco-friendly alkali source in lieu of NaOH was studied. Regardless of the variation in Pb-concentrations in leachates, all samples recorded Pb-concentrations lower than the safe limit (≤ 5 mg/l), achieving Pb-immobilization of 95.98-99.87%. The significantly reduced thermal conductivity and enhanced Pb-immobilization efficiency along with the reasonable compressive strength summarize the major innovation presented in this study.


Assuntos
Chumbo , Esgotos , Álcalis , Cloreto de Cálcio , Hidróxido de Sódio
16.
Materials (Basel) ; 15(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36431551

RESUMO

The findings of an extensive experimental research study on the usage of nano-sized cement powder and other additives combined to form cement-fine-aggregate matrices are discussed in this work. In the laboratory, dry and wet methods were used to create nano-sized cements. The influence of these nano-sized cements, nano-silica fumes, and nano-fly ash in different proportions was studied to the evaluate the engineering properties of the cement-fine-aggregate matrices concerning normal-sized, commercially available cement. The composites produced with modified cement-fine-aggregate matrices were subjected to microscopic-scale analyses using a petrographic microscope, a Scanning Electron Microscope (SEM), and a Transmission Electron Microscope (TEM). These studies unravelled the placement and behaviour of additives in controlling the engineering properties of the mix. The test results indicated that nano-cement and nano-sized particles improved the engineering properties of the hardened cement matrix. The wet-ground nano-cement showed the best result, 40 MPa 28th-day compressive strength, without mixing any additive compared with ordinary and dry-ground cements. The mix containing 50:50 normal and wet-ground cement exhibited 37.20 MPa 28th-day compressive strength. All other mixes with nano-sized dry cement, silica fume, and fly ash with different permutations and combinations gave better results than the normal-cement-fine-aggregate mix. The petrographic studies and the Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) analyses further validated the above findings. Statistical analyses and techniques such as correlation and stepwise multiple regression analysis were conducted to compose a predictive equation to calculate the 28th-day compressive strength. In addition to these methods, a repeated measures Analysis of Variance (ANOVA) was also implemented to analyse the statistically significant differences among three differently timed strength readings.

17.
Biochim Biophys Acta ; 1799(10-12): 702-16, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20965294

RESUMO

Lysine acetylation appears to be crucial for diverse biological phenomena, including all the DNA-templated processes, metabolism, cytoskeleton dynamics, cell signaling, and circadian rhythm. A growing number of cellular proteins have now been identified to be acetylated and constitute the complex cellular acetylome. Cross-talk among protein acetylation together with other post-translational modifications fine-tune the cellular functions of different protein machineries. Dysfunction of acetylation process is often associated with several diseases, especially cancer. This review focuses on the recent advances in the role of protein lysine acetylation in diverse cellular functions and its implications in cancer manifestation.


Assuntos
Lisina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional , Acetilação , Aminoácido N-Acetiltransferase/metabolismo , Animais , Humanos
18.
Cells ; 10(4)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807406

RESUMO

Dilated cardiomyopathy (DCM) is characterized by pathologic cardiac remodeling resulting in chambers enlargement and impaired heart contractility. Previous reports and our in-silico analysis support the association of DCM phenotype and impaired tissue angiogenesis. Here, we explored whether the modulation in cardiac angiogenesis partly intervenes or rescues the DCM phenotype in mice. Here, a DCM mouse model [α-tropomyosin 54 (α-TM54) mutant] was crossbred with microRNA-210 transgenic mice (210-TG) to develop microRNA-210 (miR-210) overexpressing α-TM54 mutant mice (TMx210). Contrary to wild-type (WT) and 210-TG mice, a significant increase in heart weight to body weight ratio in aged mixed-gender TMx210 and DCM mice was recorded. Histopathological analysis revealed signs of pathological cardiac remodeling such as myocardial disarray, myofibrillar loss, and interstitial fibrosis in DCM and TMx210 mice. Contrary to WT and DCM, a significant increase in angiogenic potential was observed in TMx210 and 210-TG mice hearts which is reflected by higher blood vessel density and upregulated proangiogenic vascular endothelial growth factor-A. The echocardiographic assessment showed comparable cardiac dysfunction in DCM and TMx210 mice as compared to WT and 210-TG. Overall, the present study concludes that miR-210 mediated upregulated angiogenesis is not sufficient to rescue the DCM phenotype in mice.


Assuntos
Cardiomiopatia Dilatada/fisiopatologia , Neovascularização Fisiológica , Regulação para Cima , Animais , Cardiomiopatia Dilatada/genética , Modelos Animais de Doenças , Coração/fisiopatologia , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação/genética , Neovascularização Fisiológica/genética , Fenótipo , Transdução de Sinais , Tropomiosina/genética
19.
Funct Imaging Model Heart ; 12738: 273-284, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34263263

RESUMO

Accurate and efficient quantification of cardiac motion offers promising biomarkers for non-invasive diagnosis and prognosis of structural heart diseases. Cine cardiac magnetic resonance imaging remains one of the most advanced imaging tools to provide image acquisitions needed to assess and quantify in-vivo heart kinematics. The majority of cardiac motion studies are focused on human data, and there remains a need to develop and implement an image-registration pipeline to quantify full three-dimensional (3D) cardiac motion in mice where ideal image acquisition is challenged by the subject size and heart rate and the possibility of traditional tagged imaging is hampered. In this study, we used diffeomorphic image registration to estimate strains in the left ventricular wall in two wild-type mice and one diabetic mouse. Our pipeline resulted in a continuous and fully 3D strain map over one cardiac cycle. The estimation of 3D regional and transmural variations of strains is a critical step towards identifying mechanistic biomarkers for improved diagnosis and phenotyping of structural left heart diseases including heart failure with reduced or preserved ejection fraction.

20.
Int J Prev Med ; 11: 10, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089810

RESUMO

BACKGROUND: To explore the essence of game changing on applying joint venture (JV) approach for healthcare system improvement in developing countries. METHODS: This is cross-sectional study exploring the factors influencing the successful implementation of JV for the healthcare services in low- and middle-income countries (LMICs). The study included: Qatar Statistical Authority, CIA fact book, Ministry of Health Annual Report, Hamad Medical Corporation Annual Report, Organization for Economic Cooperation and Development information, and Qatar's healthcare system history. RESULTS: The research indicated that the LMIC healthcare system would benefit from affiliation with leading technology partner for healthcare reform. The findings support the view of LMIC healthcare systems' needs to incorporate joint venture approach in implementing JV concept for process improvement and knowledge transfer to contribute in country economic growth, development, and stability. Current study explored evidence supporting decision maker and management control of JV trends in different ways in comparison with developed countries. JV can also help the organization to share the risk and cost of large capital investment. CONCLUSIONS: The present study supports observations on expending the use of JVs as approach for improvement in LMIC healthcare system. The current study confirmed the advantages of JV which include helping businesses grow faster, increasing productivity, and generating greater profits, both parties sharing the risks and costs, accessing new markets and distribution networks.

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