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MOTIVATION: Molecular dynamics (MD) is a computational experiment that is crucial for understanding the structure of biological macro and micro molecules, their folding, and the inter-molecular interactions. Accurate knowledge of these structural features is the cornerstone in drug development and elucidating macromolecules functions. The open-source GROMACS biomolecular MD simulation program is recognized as a reliable and frequently used simulation program for its precision. However, the user requires expertise, and scripting skills to carrying out MD simulations. RESULTS: We have developed an end-to-end interactive MD simulation application, MolDy for Gromacs. This front-end application provides a customizable user interface integrated with the Python and Perl-based logical backend connecting the Linux shell and Gromacs software. The tool performs analysis and provides the user with simulation trajectories and graphical representations of relevant biophysical parameters. The advantages of MolDy are (i) user-friendly, does not requiring the researcher to have prior knowledge of Linux; (ii) easy installation by a single command; (iii) freely available for academic research; (iv) can run with minimum configuration of operating systems; (v) has valid default prefilled parameters for beginners, and at the same time provides scope for modifications for expert users. AVAILABILITY AND IMPLEMENTATION: MolDy is available freely as compressed source code files with user manual for installation and operation on GitHub: https://github.com/AIBResearchMolDy/Moldyv01.git and on https://aibresearch.com/innovations.
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Simulação de Dinâmica Molecular , Software , Interface Usuário-ComputadorRESUMO
The pathogenesis of lung fibrosis involves hyperactivation of innate and adaptive immune pathways that release inflammatory cytokines and growth factors such as tumor growth factor (TGF)ß1 and induce aberrant extracellular matrix protein production. During the genesis of pulmonary fibrosis, resident alveolar macrophages are replaced by a population of newly arrived monocyte-derived interstitial macrophages that subsequently transition into alveolar macrophages (Mo-AMs). These transitioning cells initiate fibrosis by releasing profibrotic cytokines and remodeling the matrix. Here, we describe a strategy for leveraging the up-regulation of the mannose receptor CD206 in interstitial macrophages and Mo-AM to treat lung fibrosis. We engineered mannosylated albumin nanoparticles, which were found to be internalized by fibrogenic CD206+ monocyte derived macrophages (Mo-Macs). Mannosylated albumin nanoparticles incorporating TGFß1 small-interfering RNA (siRNA) targeted the profibrotic subpopulation of CD206+ macrophages and prevented lung fibrosis. The findings point to the potential utility of mannosylated albumin nanoparticles in delivering TGFß-siRNA into CD206+ profibrotic macrophages as an antilung fibrosis strategy.
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Linfotoxina-alfa , Macrófagos Alveolares , Nanopartículas , Fibrose Pulmonar , RNA Interferente Pequeno , Animais , Bleomicina/farmacologia , Modelos Animais de Doenças , Linfotoxina-alfa/genética , Macrófagos Alveolares/imunologia , Receptor de Manose , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/terapia , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genéticaRESUMO
SignificanceHepatitis C virus chronically infects approximately 1% of the world's population, making an effective vaccine for hepatitis C virus a major unmet public health need. The membrane-associated E1E2 envelope glycoprotein has been used in clinical studies as a vaccine candidate. However, limited neutralization breadth and difficulty in producing large amounts of homogeneous membrane-associated E1E2 have hampered efforts to develop an E1E2-based vaccine. Our previous work described the design and biochemical validation of a native-like soluble secreted form of E1E2 (sE1E2). Here, we describe the immunogenic characterization of the sE1E2 complex. sE1E2 elicited broadly neutralizing antibodies in immunized mice, with increased neutralization breadth relative to the membrane-associated E1E2, thereby validating this platform as a promising model system for vaccine development.
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Anticorpos Amplamente Neutralizantes , Anticorpos Anti-Hepatite C , Hepatite C , Imunogenicidade da Vacina , Proteínas do Envelope Viral , Vacinas contra Hepatite Viral , Animais , Anticorpos Amplamente Neutralizantes/biossíntese , Anticorpos Amplamente Neutralizantes/sangue , Hepatite C/prevenção & controle , Anticorpos Anti-Hepatite C/biossíntese , Anticorpos Anti-Hepatite C/sangue , Camundongos , Multimerização Proteica , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/química , Vacinas contra Hepatite Viral/imunologiaRESUMO
Distal arthrogryposis type 5D (DA5D) is clinically characterized by knee extension contractures, distal joint contractures, clubfoot, micrognathia, ptosis, and scoliosis. We report nine affected individuals from eight unrelated Indian families with DA5D. Although the overall musculoskeletal phenotype is not very distinct from other distal arthrogryposis, the presence of fixed knee extension contractures with or without scoliosis could be an important early pointer to DA5D. We also report a possible founder variant in ECEL1 along with four novel variants and further expand the genotypic spectrum of DA5D.
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Artrogripose , Efeito Fundador , Fenótipo , Humanos , Artrogripose/genética , Artrogripose/patologia , Masculino , Feminino , Índia , Criança , Pré-Escolar , Linhagem , Adolescente , Mutação/genética , Lactente , Estudos de Associação Genética , Estudos de Coortes , Genótipo , Adulto , MetaloendopeptidasesRESUMO
Hepatitis C virus (HCV) is a major worldwide health burden, and a preventive vaccine is needed for global control or eradication of this virus. A substantial hurdle to an effective HCV vaccine is the high variability of the virus, leading to immune escape. The E1E2 glycoprotein complex contains conserved epitopes and elicits neutralizing antibody responses, making it a primary target for HCV vaccine development. However, the E1E2 transmembrane domains that are critical for native assembly make it challenging to produce this complex in a homogenous soluble form that is reflective of its state on the viral envelope. To enable rational design of an E1E2 vaccine, as well as structural characterization efforts, we have designed a soluble, secreted form of E1E2 (sE1E2). As with soluble glycoprotein designs for other viruses, it incorporates a scaffold to enforce assembly in the absence of the transmembrane domains, along with a furin cleavage site to permit native-like heterodimerization. This sE1E2 was found to assemble into a form closer to its expected size than full-length E1E2. Preservation of native structural elements was confirmed by high-affinity binding to a panel of conformationally specific monoclonal antibodies, including two neutralizing antibodies specific to native E1E2 and to its primary receptor, CD81. Finally, sE1E2 was found to elicit robust neutralizing antibodies in vivo. This designed sE1E2 can both provide insights into the determinants of native E1E2 assembly and serve as a platform for production of E1E2 for future structural and vaccine studies, enabling rational optimization of an E1E2-based antigen.
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Hepacivirus/efeitos dos fármacos , Anticorpos Anti-Hepatite C/biossíntese , Hepatite C/prevenção & controle , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Neutralizantes/biossíntese , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Feminino , Expressão Gênica , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Hepatite C/imunologia , Hepatite C/patologia , Hepatite C/virologia , Humanos , Imunogenicidade da Vacina , Camundongos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Engenharia de Proteínas/métodos , Multimerização Proteica , Receptores Virais/genética , Receptores Virais/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Solubilidade , Tetraspanina 28/genética , Tetraspanina 28/imunologia , Vacinação , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Vacinas contra Hepatite Viral/administração & dosagem , Vacinas contra Hepatite Viral/química , Vacinas contra Hepatite Viral/genéticaRESUMO
The inclusion of fluorine motifs in drugs and drug delivery systems is an established tool for modulating their biological potency. Fluorination can improve drug specificity or boost the vehicle's ability to cross cellular membranes. However, the approach has yet to be applied to vaccine adjuvants. Herein, the synthesis of fluorinated bioisostere of a clinical stage immunoadjuvant-poly[di(carboxylatophenoxy)phosphazene], PCPP-is reported. The structure of water-soluble fluoropolymer-PCPP-F, which contains two fluorine atoms per repeat unit-was confirmed using 1H, 31P and 19F NMR, and its molecular mass and molecular dimensions were determined using size-exclusion chromatography and dynamic light scattering. Insertion of fluorine atoms in the polymer side group resulted in an improved solubility in acidic solutions and faster hydrolytic degradation rate, while the ability to self-assemble with an antigenic protein, lysozyme-an important feature of polyphosphazene vaccine adjuvants-was preserved. In vivo assessment of PCPP-F demonstrated its greater ability to induce antibody responses to Hepatitis C virus antigen when compared to its non-fluorinated counterpart. Taken together, the superior immunoadjuvant activity of PCPP-F, along with its improved formulation characteristics, demonstrate advantages of the fluorination approach for the development of this family of macromolecular vaccine adjuvants.
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Adjuvantes Imunológicos , Flúor , Adjuvantes Imunológicos/química , Adjuvantes de Vacinas , Polímeros/química , Compostos Organofosforados/químicaRESUMO
Omicron is a new variant of SARS-CoV-2, which is currently infecting people around the world. Spike glycoprotein, an important molecule in pathogenesis of infection has been modeled and the interaction of its Receptor Binding Domain with human ACE-receptor has been analysed by simulation studies. Structural analysis of Omicron spike glycoprotein shows the 30 mutations to be distributed over all domains of the trimeric protein, wherein the mutant residues are seen to be participating in higher number of intra-molecular interactions including two salt bridges emanating from mutant residues thereby stabilizing their conformation, as compared to wild type. Complex of Receptor Binding Domain (RBD) with human ACE-2 receptor shows seven mutations at interacting interface comprising of two ionic interactions, eight hydrogen bonds and seven Van der Waals interactions. The number and quality of these interactions along with other binding biophysical parameters suggests more potency of RBD domain to the receptor as compared to the wild type counterpart. Results of this study explains the high transmissibility of Omicron variant of SARS-CoV-2 that is currently observed across the world.
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Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/transmissão , COVID-19/virologia , SARS-CoV-2/química , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Fenômenos Biofísicos , COVID-19/metabolismo , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Simulação de Dinâmica Molecular , Mutação , Pandemias , Domínios e Motivos de Interação entre Proteínas/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Homologia Estrutural de ProteínaRESUMO
From the oasis of Cholistan, true branching heterocystous cyanobacterial strains were studied for, the cell arrangement in primary branches being mono- or bi-seriate; the shape of cells in main filament large and irregular; profused secondary branching emerging on one or both sides and tapering along their length. In these observed traits, two clear morphological taxa were recognized, both well-assorted from the previously described species of the genus Westiellopsis. Both strains showed culturing responses and were studied for antibacterial, cytotoxic, and anticancer potentials. The strain derived from the site B-10 provenance exhibited antibacterial activity against Pseudomonas (18 mm), Klebsiella (15 mm), Staphylococcus (22 mm). On the contrary, the strain of site A-44 showed no activity against any of the above-mentioned bacterial strains. The cytotoxicity assay for the strain of the B-10 site showed 36% larval mortality, whereas strain A-44 showed 24% larval mortality. Performance of the strain B-10 in MTT assay (assessed on HCT-116 cell lines) revealed a dose-dependent activity: at 200, 100, 50, and 25 µg/ml; achieving a growth inhibition of 50.15%, 40.22%, 33.72%, and 10.21%, respectively; and the strain of A-44 could only exhibit a 30.06% growth inhibition at 200 µg/ml. The 16S rRNA sequencing revealed the sequence homology with Neowestiellopsis. Based on data presented here we report two diverse taxa of true branching Nostocales from Cholistan oasis, Pakistan.
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Cianobactérias , Antibacterianos/farmacologia , Cianobactérias/genética , DNA Bacteriano/genética , Paquistão , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
DNA Gyrase is a type II topoisomerase that utilizes the energy of ATP hydrolysis for introducing negative supercoils in DNA. The protein comprises two subunits GyrA and GyrB that form a GyrA2GyrB2 heterotetramer. GyrB subunit contains the N-terminal domain (GBNTD) for ATPase activity and the C-terminal domain (GBCTD) for interaction with GyrA and DNA. Earlier structural studies have revealed three different conformational states for GBNTD during ATP hydrolysis defined as open, semi-open, and closed. Here we report, the three-dimensional structure of a new transient closed conformation of GBNTD from Salmonella Typhi (StGBNTD) at 1.94 Å resolution. Based on the structural analysis of this transient closed conformation, we propose the role of protein in the mechanism of ATP hydrolysis. We further explored the effect of pH on ATPase activity and structural stability of the GBNTD using CD and fluorescence spectroscopy at varying pH environment. Kinetic parameters obtained from the ATPase assay were correlated with its secondary and tertiary structure at their respective pH environment. The protein possessed maximum ATPase activity and structural stability at optimum pH 8. At acidic pH, a remarkable decrease in both enzymatic activity and structural stability was observed whereas at alkaline pH there was no significant change. The structural analysis of StGBNTD reveals the role of polar interactions in stabilizing the overall dimeric conformation of the protein.
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Adenosina Trifosfatases/química , DNA Girase/química , Salmonella typhi/enzimologia , Adenosina Trifosfatases/genética , Cristalografia por Raios X , DNA Girase/genética , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Domínios Proteicos , Salmonella typhi/genéticaRESUMO
Two well-defined synthetic polyphosphazene immunoadjuvants, PCPP and PCEP, were studied for their ability to potentiate the immune response to the hepatitis C virus (HCV) E2 glycoprotein antigen in vivo. We report that PCEP induced significantly higher serum neutralization and HCV-specific IgG titers in mice compared to other adjuvants used in the study: PCPP, Alum, and Addavax. PCEP also shifted the response toward the desirable balanced Th1/Th2 immunity, as evaluated by the antibody isotype ratio (IgG2a/IgG1). The in vivo results were analyzed in the context of antigen-adjuvant molecular interactions in the system and in vitro immunostimulatory activity of formulations. Asymmetric flow field flow fractionation (AF4) and dynamic light scattering (DLS) analysis showed that both PCPP and PCEP spontaneously self-assemble with the E2 glycoprotein with the formation of multimeric water-soluble complexes, which demonstrates the role of polyphosphazene macromolecules as vaccine delivery vehicles. Intrinsic in vitro immunostimulatory activity of polyphosphazene adjuvants, which was assessed using a mouse macrophage cell line, revealed comparable activities of both polymers and did not provide an explanation of their in vivo performance. However, PCEP complexes with E2 displayed greater stability against agglomeration and improved in vitro immunostimulatory activity compared to those of PCPP, which is in line with superior in vivo performance of PCEP. The results emphasize the importance of often neglected antigen-polyphosphazene self-assembly mechanisms in formulations, which can provide important insights on their in vivo behavior and facilitate the establishment of a structure-activity relationship for this important class of immunoadjuvants.
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Adjuvantes Imunológicos/administração & dosagem , Antígenos da Hepatite C/administração & dosagem , Hepatite C/prevenção & controle , Proteínas do Envelope Viral/administração & dosagem , Vacinas contra Hepatite Viral/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Feminino , Hepacivirus/imunologia , Hepatite C/imunologia , Hepatite C/virologia , Antígenos da Hepatite C/imunologia , Antígenos da Hepatite C/ultraestrutura , Humanos , Imunogenicidade da Vacina , Camundongos , Modelos Animais , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/imunologia , Polímeros/administração & dosagem , Polímeros/química , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/ultraestrutura , Relação Estrutura-Atividade , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/isolamento & purificação , Proteínas do Envelope Viral/ultraestrutura , Vacinas contra Hepatite Viral/imunologiaRESUMO
RATIONALE: Increased expression of CLIC4 (chloride intracellular channel 4) is a feature of endothelial dysfunction in pulmonary arterial hypertension, but its role in disease pathology is not fully understood. OBJECTIVE: To identify CLIC4 effectors and evaluate strategies targeting CLIC4 signaling in pulmonary hypertension. METHODS AND RESULTS: Proteomic analysis of CLIC4-interacting proteins in human pulmonary artery endothelial cells identified regulators of endosomal trafficking, including Arf6 (ADP ribosylation factor 6) GTPase activating proteins and clathrin, while CLIC4 overexpression affected protein regulators of vesicular trafficking, lysosomal function, and inflammation. CLIC4 reduced BMPRII (bone morphogenetic protein receptor II) expression and signaling as a result of Arf6-mediated reduction in gyrating clathrin and increased lysosomal targeting of the receptor. BMPRII expression was restored by Arf6 siRNA, Arf inhibitor Sec7 inhibitor H3 (SecinH3), and inhibitors of clathrin-mediated endocytosis but was unaffected by chloride channel inhibitor, indanyloxyacetic acid 94 or Arf1 siRNA. The effects of CLIC4 on NF-κB (nuclear factor-kappa B), HIF (hypoxia-inducible factor), and angiogenic response were prevented by Arf6 siRNA and SecinH3. Sugen/hypoxia mice and monocrotaline rats showed elevated expression of CLIC4, activation of Arf6 and NF-κB, and reduced expression of BMPRII in the lung. These changes were established early during disease development. Lung endothelium-targeted delivery of CLIC4 siRNA or treatment with SecinH3 attenuated the disease, reduced CLIC4/Arf activation, and restored BMPRII expression in the lung. Endothelial colony-forming cells from idiopathic pulmonary hypertensive patients showed upregulation of CLIC4 expression and Arf6 activity, suggesting potential importance of this pathway in the human condition. CONCLUSIONS: Arf6 is a novel effector of CLIC4 and a new therapeutic target in pulmonary hypertension.
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Fatores de Ribosilação do ADP/antagonistas & inibidores , Anti-Hipertensivos/farmacologia , Canais de Cloreto/metabolismo , Células Endoteliais/efeitos dos fármacos , Hipertensão Pulmonar/prevenção & controle , Proteínas Mitocondriais/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Terapêutica com RNAi , Triazóis/farmacologia , Fator 6 de Ribosilação do ADP , Fatores de Ribosilação do ADP/genética , Fatores de Ribosilação do ADP/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Células Cultivadas , Canais de Cloreto/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipóxia/complicações , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/genética , Terapia de Alvo Molecular , Monocrotalina , Proteômica/métodos , Artéria Pulmonar/metabolismo , Artéria Pulmonar/fisiopatologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Transdução de SinaisRESUMO
We report a 55-year-old male patient with lone paroxysmal atrial fibrillation who underwent routine transesophageal echocardiography (TOE) at our institution. In a mid-esophageal 125° three-chamber angulation, a distinct thinning of the left atrial (LA) wall was observed, forming a 7 × 4 mm canal with only a small membrane separating the LA from the pericardial space. Cardiac magnetic resonance imaging diagnosed a small LA diverticulum. To the best of our knowledge, this is the first manuscript describing detection of a small LA diverticulum via TOE.
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Apêndice Atrial , Fibrilação Atrial , Divertículo , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/diagnóstico por imagem , Divertículo/diagnóstico por imagem , Ecocardiografia Transesofagiana , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
AIM: The International Endodontic Journal (IEJ) has served as a platform for research and clinical practice in Endodontics since 1967. This study provides a bibliographic analysis and overview of the publications that have appeared in the IEJ from 1967 to 2020. METHODOLOGY: A literature search was performed in Elsevier's Scopus database to locate all the publications of the International Endodontic Journal. Various bibliometric software packages including the open-source visualization software Gephi and Biblioshiny (version 2.0) were employed for data visualization and analysis. RESULTS: A total of 3739 records with citation and bibliographic details were selected and retrieved to allow a bibliometric analysis to be performed. The bibliometric analysis indicates that the IEJ has grown both in terms of productivity and influence. Over time, the journal has been associated with an increase in the number of manuscripts published and the citations they have attracted, but with minor downward fluctuations in citations in the last few years. Bibliographic coupling of the IEJ articles revealed that the major research themes published in the journal include 'endodontics', 'root canal treatment', 'calcium hydroxide', 'apical periodontitis', 'mineral trioxide aggregate', 'microbiology', 'cyclic fatigue', 'cone-beam computed tomography' and 'micro-computed tomography'. Authors affiliated to institutions in the UK were the major contributors to the journal and were linked with other countries such as Brazil, USA and Malaysia. The largest number of publications were from the University of São Paulo, Brazil. CONCLUSION: The IEJ is one of the leading journals in Endodontology and has been providing a platform for innovative research and clinical reports for more than 50 years. Publications have been associated with a wide range of authors, institutions and countries around the world.
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Bibliometria , Endodontia , Tomografia Computadorizada de Feixe Cônico , Bases de Dados Factuais , Microtomografia por Raio-XRESUMO
AIM: To fabricate and characterize nano-hydroxyapatite (nHA) grafted and non-grafted glass fibre-based endodontic posts. METHODOLOGY: Experimental glass fibre posts were fabricated using silanized nHA grafted (ex-HA) and non-grafted glass fibre (ex-P) reinforced resins. The structural analysis and morphological patterns were analysed with Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. EverStick® glass fibre posts (eS) were used as a control group. The degree of conversion, flexural strength, and flexural modulus was investigated and the fractured structure was evaluated with a scanning electron microscope. Root canals were prepared in human extracted teeth restored with experimental and control posts. The push-out bond strength was evaluated with radicular dentine at days 7, 30, and 90, and the presence of voids at the interface were measured at day 1, 7, 30, and 90 with micro-computed tomography. The Shapiro-Wilk test and one-way ANOVA post-hoc Tukey's test were performed. The level of significance was set at 0.05. RESULTS: The SEM and FTIR confirmed the presence of a silane-coupling agent on the glass fibres. The ex-HA post had a significantly lower degree of conversion compared to the ex-P post (p = .0008), but a significantly higher conversion than the eS post (p = .0014). The maximum flexural strength value was obtained with the ex-HA post with an insignificant difference (p = .366) compared to ex-P post and a significant difference (p = .029) compared to the eS post. The flexural modulus of ex-HA, ex-P, and eS posts were significantly different (p = .037). Similarly, the ex-HA post had a significantly higher push-out bond strength at days 7 and 30 (p = .037) compared to the ex-P and eS posts. The volume of voids had a nonlinear behaviour amongst the groups with no significant difference between the posts. CONCLUSION: The fabrication of the experimental posts was successful and the ex-HA post had greater flexural strength and push-out bond strength compared to the ex-P post. The degree of conversion of the ex-HA post was lower than the ex-P and eS posts. The volume of voids of ex-HA and ex-P posts was lower than that of eS posts.
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Colagem Dentária , Técnica para Retentor Intrarradicular , Apatitas , Resinas Compostas , Análise do Estresse Dentário , Dentina , Vidro , Humanos , Laboratórios , Teste de Materiais , Cimentos de Resina , Microtomografia por Raio-XRESUMO
How to cite this article: Ansari AS. Therapeutic Options for the Treatment of Carbapenem-resistant Enterobacteriaceae Infections: Hope in the Times of Hype and Despair. Indian J Crit Care Med 2021;25(7):752-753.
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INTRODUCTION: Radiofrequency (RF) ablation is a commonly used tool in the invasive electrophysiology laboratory to treat a variety of rhythm disorders. Reliable creation of transmural ablation lesions is crucial for long-term success. Lesion size index (LSI) is a multiparametric index that incorporates time, power, contact force (CF), and impedance data recorded during RF ablation in a weighted formula and has been shown to predict the extent of myocardial tissue lesions. Whether the force stability of contact influences lesion size in LSI-guided ablations is unknown. OBJECTIVES: The aim of this study was to analyze the influence of the force stability of contact on lesion size during LSI-guided ablations in an ex-vivo model. METHODS AND RESULTS: A total of 267 RF lesions (n = 6 hearts) were created on porcine myocardial slabs by using an open-tip irrigated ablation catheter with the following settings: 35 W with either intermittent (varied between 0 and up to 20 g), variable (10 to 20 g), or constant tissue contact (15 g) in a perpendicular or parallel fashion (applied manually) up to a target LSI of either 5 or 6. Subsequently, lesion width and depth were determined. Lesion width was mainly influenced by catheter tip orientation and LSI, whereas lesion depth was mainly influenced by LSI alone. The force stability of catheter contact had no relevant impact on lesion width or depth. CONCLUSION: The force stability of catheter contact has only little effect on lesion depth or width in LSI-guided catheter ablation while the catheter orientation primarily affects lesion width.
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Procedimentos Cirúrgicos Cardíacos/métodos , Ablação por Radiofrequência/métodos , Animais , Procedimentos Cirúrgicos Cardíacos/instrumentação , Técnicas In Vitro , Modelos Animais , Ablação por Radiofrequência/instrumentação , SuínosRESUMO
BACKGROUND: Atrial and ventricular arrhythmias significantly contribute to morbidity and mortality of patients with cardiac disease. Ablation of these arrhythmias has shown to improve clinical outcomes, yet targeted ablation strategies rely on proper mapping capabilities. In the present study, we compare different modes of high-resolution mapping in clinically relevant arrhythmias using HD grid. METHODS AND RESULTS: Using the Advisor™ HD Grid Mapping Catheter in either the standard, the wave (bipolar along spline and bipolar orthogonal) or the wave diagonal setting, low-voltage areas were determined. Low-voltage was defined as local electrograms with an amplitude <0.5 mV (bipolar; atria/ventricle) or <4 mV (unipolar; ventricle). Ultra high-density mapping in 47 patients with ventricular tachycardia, ventricular premature beats, atrial fibrillation and atrial tachycardia provided reliable information for the understanding of the arrhythmia mechanism resulting in safe ablation procedures. Regions of low voltage were significantly decreased by 14 ± 2% and 31 ± 3% with wave and wave diagonal settings as compared to standard settings, respectively. CONCLUSION: Substrate mapping and risk stratification relies on proper low voltage discrimination. Even though the Advisor™ HD Grid Mapping Catheter was safely used in all cases, the extent of low voltage areas was mapping-mode dependent.
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Ablação por Cateter , Taquicardia Ventricular , Catéteres , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Humanos , Taquicardia Ventricular/cirurgiaRESUMO
AIM/OBJECTIVE/INTRODUCTION: Cytokine storm or cytokine release syndrome (CRS) is inevitable in severe and critically ill patients with novel coronavirus disease-2019 (COVID-19). This review aimed to discuss current therapeutic options for the management of CRS in COVID-19. BACKGROUND: Cytokine storm is caused by the colossal release of proinflammatory cytokines [e.g., IL (interleukin)-2, IL-6, IL-8 TNF (tumor necrosis factor)-α, etc.] causing dysregulated, hyperimmune response. This immunopathogenesis leads to acute lung injury and acute respiratory distress syndrome (ARDS). Targeting cytokine storm with the therapies that are already available in India with the support of published guidelines and consensus can assist in achieving a better outcome in COVID-19. REVIEW RESULTS: We predominantly included published guidelines or consensus recommendations about the management of cytokine storm in COVID-19. From the existing literature evidence, it is observed that among the currently available agents, low-dose corticosteroids and heparin can be beneficial in managing cytokine storm. The use of serine protease inhibitors such as ulinastatin has been advised by some experts. Though therapies such as high-dose vitamin C and interleukin-6 inhibitors (e.g., tocilizumab) have been advised, the evidence regarding their use for cytokine storm in COVID-19 is limited. Therapies such as Janus kinase inhibitors (JAK) inhibitors and Neurokinin-1 receptor (NK-1) antagonists are still in research. Besides, pharmaceutical treatments, use of blood purification strategies, and convalescent plasma may be life-saving options in some of the critically ill COVID-19 patients. For these therapies, there is a need to generate further evidence to substantiate their use in CRS management. CONCLUSION: Current management of COVID-19 is preventive and supportive. Different therapies can be used to prevent and treat the cytokine storm. More research is needed for further supporting the use of these treatments in COVID-19. HOW TO CITE THIS ARTICLE: Mehta Y, Dixit SB, Zirpe KG, Ansari AS. Cytokine Storm in Novel Coronavirus Disease (COVID-19): Expert Management Considerations. Indian J Crit Care Med 2020;24(6):429-434.
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Distal-less homeobox 3 (Dlx3), a member of the Dlx family of homeobox proteins, is a transcriptional activator of runt-related transcription factor 2 (Runx2) during osteogenic differentiation. It has been demonstrated that forced expression of Runx2 induces an osteogenic program and ectopic calcification in muscles. Therefore, it would be reasonable to predict that Dlx3 also affects myogenic differentiation. The relationship between Dlx3 and myogenesis, however, remains poorly understood. Therefore, in this study, the role and regulation of Dlx3 during myogenic differentiation were investigated. Expression level of Dlx3 was downregulated in human mesenchymal stem cells (MSCs), mouse MSCs, and C2C12 cells cultured in myogenic medium. Dlx3 level was inversely correlated with myogenic differentiation 1 and the muscle-specific microRNA, microRNA-133 (miR-133). The expression level of Runx2 was closely regulated by Dlx3 even under myogenic conditions. Overexpression of Dlx3 markedly downregulated expression levels of myogenic transcription factors and myotube formation in C2C12 cells, whereas Dlx3 knockdown enhanced myogenic differentiation. The Dlx3 3'-untranslated region (3'-UTR) has two potential binding sites for miR-133. Luciferase reporter assays demonstrated that Dlx3 is a direct target of miR-133a and miR-133b, and that the two target sites are redundantly active. Taken together, these results suggest that Dlx3 is a negative regulator of myogenic differentiation and that miR-133a and miR-133b enhance myogenic differentiation, partly through inhibition of Dlx3 expression via direct targeting of the Dlx3 3'-UTR.
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MoS2 2D nanosheets (NS) with intercalated 0D quantum dots (QDs) represent promising structures for creating low-dimensional (LD) resistive memory devices. Nonvolatile memristors based 2D materials demonstrate low power consumption and ultrahigh density. Here, the observation of a photoinduced phase transition in the 2D NS/0D QDs MoS2 structure providing dynamic resistive memory is reported. The resistive switching of the MoS2 NS/QD structure is observed in an electric field and can be controlled through local QD excitations. Photoexcitation of the LD structure at different laser power densities leads to a reversible MoS2 2H-1T phase transition and demonstrates the potential of the LD structure for implementing a new dynamic ultrafast photoresistive memory. The dynamic LD photomemristive structure is attractive for real-time pattern recognition and photoconfiguration of artificial neural networks in a wide spectral range of sensitivity provided by QDs.