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In the present study, magnesium nanoparticles (Mg NPs) were synthesized utilizing an aqueous extract of Berberis aristate rhizome and evaluated for antimicrobial and anti-inflammatory activity. Technofunctional properties of rhizome powder were evaluated and during thermal stability evaluation four stages of decomposition with a maximum delta Y value of 76.04 % was observed. Optimization of Mg NPs was carried out by employing eight different concentrations (C1-C8) and the C4 showed maximum absorbance at 330 nm confirming the NPs synthesis. The Mg NPs showed the particle size of 62 nm, zeta potential of -24.7 mV and hexagonal mprphology. Potential inhibition against S. aureus and E. coli (76.78 ± 0.05% and 74.62 ± 0.17%)and anti-inflammatory activity ranging from 42.43 ± 0.07-82.92 ± 0.04% was observed for Mg NPs. Therefore, green synthesis of Mg NPs is a promising approach for the development ofbiological active NPs to cure microbial infections.
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An HIV outbreak investigation during 2017-2018 in Unnao District, Uttar Pradesh, India, unearthed high prevalence of hepatitis C virus (HCV) antibodies among the study participants. We investigated these HCV infections by analyzing NS5B and core regions. We observed no correlation between HIV-HCV viral loads and clustering of HCV sequences, regardless of HIV serostatus. All HCV isolates belonged to genotype 3a. Monophyletic clustering of isolates in NS5B phylogeny indicates emergence of the outbreak from a single isolate or its closely related descendants. The nucleotide substitution rate for NS5B was 6 × 10-3 and for core was 2 × 10-3 substitutions/site/year. Estimated time to most recent common ancestor of these isolates was 2012, aligning with the timeline of this outbreak, which might be attributable to unsafe injection practices while seeking healthcare. HIV-HCV co-infection underlines the need for integrated testing, surveillance, strengthening of healthcare systems, community empowerment, and molecular analyses as pragmatic public health tools.
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Infecciones por VIH , Hepatitis C , Brotes de Enfermedades , Infecciones por VIH/epidemiología , Hepacivirus , Hepatitis C/epidemiología , Humanos , India/epidemiología , FilogeniaRESUMEN
Background & objectives: The COVID-19 pandemic had a distinct impact on scientific research and Ethics Committees (ECs). We conducted a mixed-methods investigation to understand the issues faced and solutions identified by ECs during this pandemic in India. Methods: A quantitative online survey form (30 members) and qualitative in-depth interviews (10 members) from various ECs were conducted. Thematic content analysis for qualitative and proportion analysis for quantitative data was carried out. Results: During the online survey, an average difficulty score, which was measured using the Visual Analogue Scale, was 5.3 (SD 2.1). Pressure for expedited approvals was felt by EC members with a drastic increase in the number of submission of research projects. The scarcity of information on investigational products (IPs) and requisite consent process posed major hurdles. Ongoing non-COVID studies and post-graduate dissertations were badly hit due to the shift in attention towards COVID-related research. Non-familiarity with virtual technology and lack of face-to-face interactions were highlighted as demerits. However, a few of the EC members welcomed newer methods, being time-saving, convenient and reducing travel hassles. Site monitoring and severe adverse event-related analyses were also negatively impacted upon. Solutions included the alternate methods of consenting (virtual, abbreviated), a detailed explanation of the protocol and IPs and benefits versus risk assessment. Interpretation & conclusions: Despite various challenges posed by the COVID-19 pandemic, the ECs in India steered well through the hurdles. Moreover, adapting a hybrid mode, technical training and updating guidelines were perceived as urgent by EC members.
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COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Comités de Ética en Investigación , Miembro de Comité , Encuestas y CuestionariosRESUMEN
Background & objectives: Globally, several countries consider HIV self-test as an important element in the toolbox to end AIDS by 2030. Against this background, the present investigation was conducted to pilot test the performance of an indigenous HIV oral self-test (HIVOST) and explore its acceptability. The overall purpose was to examine if this kit could serve as a promising tool and merit future larger clinical evaluation. Methods: A concurrent mixed-method investigation was undertaken during March-October 2019. One hundred and thirty two consecutive HIV/sexually transmitted diseases/tuberculosis clinic attendees were invited for participation; of whom, 100 were enrolled, and among them, 40 provided consent for qualitative in-depth interviews. The HIVOST kit assessed for its performance served as the 'index test', which worked on the principle of lateral flow chromatography. The results of the HIVOST were interpreted independently by the study physicians and participants at 20 min. HIVOST kit performance was assessed against the HIV confirmatory blood test result based on the national algorithm (3 rapid test or 1 ELISA and 2 rapid test) serving as the 'reference'. Sensitivity, specificity, positive predictive value, negative predictive value and inter-rater agreement were estimated. The voices and concerns of the study participants were coded followed by identification of qualitative themes and ideas. Results: The sensitivity and specificity of the index test at the end of 20 min as interpreted by the participants were 83.3 per cent [95% confidence interval (CI): 69.8 to 92.5] and 98 per cent (95% CI: 89.4 to 99.5), respectively. Study physicians and participants independently interpreted HIVOST results with substantial inter-rater agreement (kappa value 0.88; 95% CI: 0.78-0.97). All HIVOST test strips were valid. Majority of the participants preferred saliva over blood for HIV self-test. 'Comfort', 'confidentiality' and 'convenience' were the perceived advantages of HIVOST. Some of the participants wished the package inserts contained 'how-to-do instructions in local languages', 'expiry date (if any)' and 'contact helpline number'. A few of them highlighted the need for a confirmatory HIV result following oral self-test. Concerns of the participants revolved around potential self-harm following HIVOST-positive result and safe disposal of kits. Interpretation & conclusions: Two major highlights of the present investigation are (i) high level of concordance in HIVOST results interpreted by participants and physicians, and (ii) encouraging level of acceptance of HIVOST. These findings and encouraging HIVOST performance statistics lend support towards large-scale clinical evaluation of this index test.
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Infecciones por VIH , Tuberculosis , Estudios Transversales , Infecciones por VIH/diagnóstico , Humanos , Proyectos Piloto , Sensibilidad y Especificidad , Tuberculosis/diagnósticoRESUMEN
Just over a million people died globally in 2019 due to antibiotic resistance caused by ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The World Health Organization (WHO) also lists antibiotic-resistant Campylobacter and Helicobacter as bacteria that pose the greatest threat to human health. As it is becoming increasingly difficult to discover new antibiotics, new alternatives are needed to solve the crisis of antimicrobial resistance (AMR). Bacteria commonly found in complex communities enclosed within self-produced matrices called biofilms are difficult to eradicate and develop increased stress and antimicrobial tolerance. This review summarises the role of antimicrobial peptides (AMPs) in combating the silent pandemic of AMR and their application in clinical medicine, focusing on both the advantages and disadvantages of AMPs as antibiofilm agents. It is known that many AMPs display broad-spectrum antimicrobial activities, but in a variety of organisms AMPs are not stable (short half-life) or have some toxic side effects. Hence, it is also important to develop new AMP analogues for their potential use as drug candidates. The use of one health approach along with developing novel therapies using phages and breakthroughs in novel antimicrobial peptide synthesis can help us in tackling the problem of AMR.
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Antiinfecciosos , Enterococcus faecium , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Péptidos Antimicrobianos , Biopelículas , Farmacorresistencia Bacteriana , Humanos , Pruebas de Sensibilidad Microbiana , PandemiasRESUMEN
Cathepsin C plays a key role in the activation of several degradative enzymes linked to tissue destruction in chronic inflammatory and autoimmune diseases. Therefore, Cathepsin C inhibitors could potentially be effective therapeutics for the treatment of diseases such as chronic obstructive pulmonary disease (COPD) or acute respiratory distress syndrome (ARDS). In our efforts towards the development of a novel series of Cathepsin C inhibitors, we started working around AZD5248 (1), an α-amino acid based scaffold having potential liability of aortic binding. A novel series of amidoacetonitrile based Cathepsin C inhibitors were developed by the application of a conformational restriction strategy on 1. In particular, this work led to the development of a potent and selective Cathepsin C inhibitor 3p, free of aortic binding liability.
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Aorta/metabolismo , Tratamiento Farmacológico de COVID-19 , Catepsina C/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/síntesis química , Inhibidores de Cisteína Proteinasa/farmacología , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Acetonitrilos/química , Acetonitrilos/farmacología , Aminoácidos/química , Aminoácidos/farmacología , Compuestos de Bifenilo/farmacología , COVID-19/complicaciones , Humanos , Modelos Moleculares , Estructura Molecular , Síndrome de Dificultad Respiratoria/etiología , Relación Estructura-ActividadRESUMEN
BACKGROUND: Ending AIDS by 2030 is a global target, to which India is a signatory. HIV-self-test (HIVST) coupled with counselling and AIDS-care, including antiretroviral therapy, has the potential to achieve this. However, national programs are at varying stages of acceptance of HIVST, as discussions around its introduction spark controversy and debates. HIV-self-test, as yet, is not part of the AIDS control program in India. Against this backdrop, we explored acceptability of an HIV oral self-test (HIVOST) among truckers and young men and women. METHODS: A qualitative investigation with 41 in-depth-interviews and 15 group discussions were conducted in the district of Pune, in the western state of Maharashtra, India. These interactions were built around a prototype HIVOST kit, helped in taking the discussions forward. The software N-vivo (version 11.0) was used to manage the volumes of data generated through the aforementioned process. The study was conducted during June through December, 2019. RESULTS: While the truckers belonged to the age bracket 21-67 year, the youths were in the age group 18-24 year. 'Ease of doing HIVOST' and 'fear of needle pricks' were the reasons behind acceptance around HIVOST by both the study groups. Truckers felt that HIVOST would encourage one to know one's HIV status and seek help as appropriate. Accuracy of HIVOST result and disposal of the kits following use were concerns of a few. Most of the participants preferred saliva over blood as the specimen of choice. Instructions in local language reportedly would enable test-use by self. The truck drivers preferred undertaking HIVOST at the truckers-friendly 'Khushi clinics' or in the vehicle, while youths preferred the privacy of home. Some of the young men mis-perceived the utility of HIVOST by referring to doing a test on a partner immediately prior to sexual encounter. On the other hand, a few truckers had wrong information on HIV cure. CONCLUSIONS: Overall, the study communities expressed their acceptance towards HIV-self-test. The National AIDS Control Program, India would benefit by drawing upon the findings of the current investigation. Existing myths and misconceptions around HIV test and treatment require program attention.
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Infecciones por VIH , Autoevaluación , Adolescente , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Humanos , India , Masculino , Tamizaje Masivo , Vehículos a Motor , Conducta SexualRESUMEN
In the present study, the adhesive and viscoelastic properties of polydimethylsiloxane (PDMS) based nanocomposite pressure sensitive adhesives (PSAs) with embedded electrospun polyacrylonitrile (PAN) and polyvinyl alcohol (PVA) nanofibers as fillers were investigated. PDMS nanocomposite adhesive films using PAN and PVA nanofibers were synthesized by dispersing fillers in the matrix by a solvent mixing process. The adhesion strength and reusability of the prepared nanocomposite PSA films were measured using peel tests as the fraction of nanofibers in the polymer matrix is increased. The variations of the adhesive properties of the PSAs as function of the type and loading of filler were related to their rheological properties in terms of shear and elastic moduli. Although 3-fold enhancement of the adhesion strength was achieved with 0.5 wt% loading for both types (PAN and PVA) of nanocomposites as compared to elastic PDMS, the composite adhesive with PAN nanofibers can provide a superior balance of rheological properties, resulting in improved reusability over other PSAs. The differences in the adhesion and viscoelastic properties of the composite PSAs are attributed to the polymer chemistry, processability, and architecture of the electrospun nanofibers in the soft PDMS matrix.
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BACKGROUND: Emergence and spread of ß-lactamase resistant Klebsiella pneumoniae have posed a serious threat, especially in paediatric patients globally. The present study focuses on explore drug resistance profile and molecular characterization of carbapenemase and extended-spectrum ß-lactamase producing K. pneumoniae isolated from paediatric patients in Shenzhen, China. METHODS: Present study, a total of 31 isolates of multi-drug resistant K. pneumoniae were collected from Shenzhen Children's Hospital, China during Jan 2014 to December 2015. ESBLs production was confirmed by using the combination disc diffusion method followed by antimicrobial susceptibility. In addition, ß-lactamase encoding genes were determined by PCR assay and sequencing. The genotypic diversity and phylogenetic relationship were determined by multi-locus sequence typing (MLST) method and pulsed-field gel electrophoresis (PFGE). RESULTS: We examined 31, unique K. pneumoniae isolates collected from 2014 and 2015 in Shenzhen Children's Hospital, China. All the 31 isolates 100% were resistant to ceftazidime, ertapenem, ampicillin, cefazolin and ampicillin-sulbactam followed by ceftriaxone 94% (n = 29), aztreonam 89% (n = 26), cefepime 84% (n = 26), nitrofurantoin 75% (n = 24), piperacillin 52% (n = 16), and levofloxacin 49% (n = 15). Of the 31 ß-lactamase gene coding isolates, blaCTX-M was mainly detected in about 100% (n = 31), followed by blaKPC 71% (n = 22), blaSHV 61% (n = 19), blaNDM 25% (n = 8), blaCYM 13% (n = 4), blaOXA-48 9% (n = 3), blaGES 9% (n = 3) and blaTEM 6% (n = 2). Seventeen distinct sequences type were observed with ST20 being mostly identified 16% (n = 5). Pulsed-field gel electrophoresis (PFGE) typing showed that identical profile for the isolates recovered from the Department of Intensive Care Unit and Department of Neurology of our hospital. Plasmid replicon typing result indicates the presence of IncFIS type as highest in all isolates as 61% (n = 19), followed by IncFIB 23% (n = 7), IncFIA and IncFIC 16% (n = 5) each. CONCLUSION: Our study reports the occurrence and spread of extended ß-lactamase K. pneumoniae ST20 and ST2407 for the first time, in Shenzhen, particularly in paediatric patients. To prevent and control the infection by limiting the spread of infection-causing organisms it is very crucial to detect the presence of resistant genes at an early stage.
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Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Niño , Salud Infantil , Preescolar , China/epidemiología , Femenino , Genes Bacterianos , Humanos , Lactante , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/prevención & control , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , FilogeniaRESUMEN
Hyaluronidase (hyase) is a hyaluronic acid (HA) depolymerizing enzyme produced by many pathogenic bacteria as a virulence factor to establish and spread infections. Present studies established that a steroidal fraction (SF) isolated from leaves of Carissa carandas act as a strong hyase inhibitor. The kinetic parameters involved in the inhibition of hyase by purified SF were studied and compared with standard hyase inhibitor quercetin. The purified SF showed the highest inhibition with an IC50 of 5.19 mM in comparison with a standard inhibitor, quercetin (IC50 8.63 mM). The inhibition constant (Ki) of purified SF determined by Dixon plot was 8.32 mM, which was significantly lower than that of quercetin standard. The kinetic behavior of enzyme hyase revealed to be more complex than classical competitive and uncompetitive inhibition where inhibitor affects both Km and Vmax. The inhibitor (I) favored the binding to the enzyme-substrate (ES) complex where Km value appeared to decrease (Kmapp < Km). The inhibitor also leads to decrease in the apparent maximum velocity of the enzyme-substrate reaction (Vmaxapp < Vmax). These results signpost toward mixed nature of inhibition of enzyme hyase by purified SF. Anti-hyaluronidase activity by a bioactive metabolite from C. carandas has not been reported so far and has high therapeutic potential against spread of pathogen and its toxins in the host.
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Apocynaceae/química , Inhibidores Enzimáticos/farmacología , Hialuronoglucosaminidasa/antagonistas & inhibidores , Esteroides/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Hialuronoglucosaminidasa/química , Cinética , Hojas de la Planta/química , Esteroides/química , Esteroides/aislamiento & purificaciónRESUMEN
Background: mcr-1-mediated colistin resistance in Enterobacteriaceae is concerning, as colistin is used in treating multidrug-resistant Enterobacteriaceae infections. We identified trends in human fecal mcr-1-positivity rates and colonization with mcr-1-positive, third-generation cephalosporin-resistant (3GC-R) Enterobacteriaceae in Guangzhou, China, and investigated the genetic contexts of mcr-1 in mcr-1-positive 3GC-R strains. Methods: Fecal samples were collected from in-/out-patients submitting specimens to 3 hospitals (2011-2016). mcr-1 carriage trends were assessed using iterative sequential regression. A subset of mcr-1-positive isolates was sequenced (whole-genome sequencing [WGS], Illumina), and genetic contexts (flanking regions, plasmids) of mcr-1 were characterized. Results: Of 8022 fecal samples collected, 497 (6.2%) were mcr-1 positive, and 182 (2.3%) harbored mcr-1-positive 3GC-R Enterobacteriaceae. We observed marked increases in mcr-1 (0% [April 2011] to 31% [March 2016]) and more recent (since January 2014; 0% [April 2011] to 15% [March 2016]) increases in human colonization with mcr-1-positive 3GC-R Enterobacteriaceae (P < .001). mcr-1-positive 3GC-R isolates were commonly multidrug resistant. WGS of mcr-1-positive 3GC-R isolates (70 Escherichia coli, 3 Klebsiella pneumoniae) demonstrated bacterial strain diversity; mcr-1 in association with common plasmid backbones (IncI, IncHI2/HI2A, IncX4) and sometimes in multiple plasmids; frequent mcr-1 chromosomal integration; and high mobility of the mcr-1-associated insertion sequence ISApl1. Sequence data were consistent with plasmid spread among animal/human reservoirs. Conclusions: The high prevalence of mcr-1 in multidrug-resistant E. coli colonizing humans is a clinical threat; diverse genetic mechanisms (strains/plasmids/insertion sequences) have contributed to the dissemination of mcr-1, and will facilitate its persistence.
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Portador Sano/microbiología , Colistina/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/genética , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Portador Sano/epidemiología , Cefalosporinas/farmacología , China/epidemiología , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Heces/microbiología , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Prevalencia , Secuenciación Completa del GenomaRESUMEN
Fabrication of large area, multiscale microtextured surfaces engineered for antiadhesion properties remains a challenge. Compared to an elastic surface, viscoelastic solids show much higher surface stickiness, tack, and adhesion owing to the increased contact area and energy dissipation. Here, we show a simple, low cost, large-area and high throughput method with roll-to-roll compatibility to fabricate multiscale, rough microstructures resistant to adhesion in a viscoelastic layer by controlled tearing of viscous film. Even a high adhesive strength viscoelastic solid layer, such as partially cured PDMS, is made nonsticky simply by its controlled tearing. The torn surface shows a fracture induced, self-organized leaflike micropattern resistant to sticking. The topography and adhesion strength of these structures are readily tuned by changing the tearing speed and the film thickness. The microtexture displays a springlike recovery, low adhesive strength, and easy release properties even under the high applied loads.
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We investigate surface and sub-surface nanomechanical properties of nanocomposites based on a crosslinked polydimethylsiloxane (PDMS) elastomer and electrospun polyacrylonitrile (PAN) nanofibers. Fabrication of PDMS substrates with anisotropy with respect to surface elasticity and their characterization in terms of local nanomechanical properties are important for many areas of adhesion applications. PDMS nanocomposite substrates with variations in surface elasticity over large areas are prepared by controllably embedding electrospun PAN nanofibers (â¼600 nm) in a PDMS matrix using the solution casting technique. Variations of local surface stiffness properties of prepared composites are measured using force spectroscopy and force mapping modes of atomic force microscopy and compared with their macroscopic (bulk) mechanical properties. Since the surface of the prepared nanocomposite is elastically non-homogeneous, our studies are mainly focused on the investigation of the hysteresis (plasticity index) between loading and unloading curves which is a measure of energy dissipation in AFM indentation experiments. The distribution of the local plasticity index in the PAN/PDMS composites is related to the specific organization of electrospun nanofibers at the surface and sub-surface layers of the PDMS matrix. We observed that embedding 0.1-1% PAN nanofibers induces anti-plasticization effects for lower (0.1%) and higher (1%) concentrations of PAN nanofibers which represent the formation of interpenetrating networks and mat-like blended structures of PAN nanofibers within the PDMS matrix.
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The finding described in this study is the first report of leaf spot disease of cotton caused by Curvularia verruculosa surveyed in the state of Maharashtra (India). The isolated phytopathogenic fungal strain was identified using morphological characteristics and molecular identification of ITS gene sequence (MF784436) and D1D2 region of LSU gene (KY978073). The ability of fungal strain to secrete hydrolytic enzymes viz., pectinase, xylanase, protease, cellulase and lipase was detected. The secretion profile of hydrolytic enzymes by C. verruculosa was also examined in planta and in vitro. The secretion of cellulase, xylanase and protease was found to be inducible on cotton-stalk powder containing media; while secretion of pectinase and lipase was constitutive in glucose containing medium. The hydrolytic enzymes secretion during etiological progression of disease was detected on cotton leaves at regular interval of 24 h up to 10 days. A significant correlation (P < 0.05) was observed between hydrolytic enzymes secretion and disease severity index. The increased level of hydrolytic enzymes in infected plant sample indicates their role in disease progression. The newly documented fungal phytopathogen Curvularia verruculosa was deposited at National Fungal Culture Collection of India, Pune with accession number of NFCCI-4119.
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Implantation of temporary pacemaker lead is commonly performed procedure and is usually safe, but can sometimes develop rare and serious complication like intracardiac lead knotting which may require challenging retrieval techniques. We report a case of successful percutaneous retrieval of unusually knotted right internal jugular venous temporary pacing lead via left femoral transvenous approach using snare over a long sheath after cutting the electrode proximally and thus avoiding any surgical intervention.
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Inspired by the detachment mechanics of natural adhesive pads, we studied the change in cavity shape during peel tests on a 10% cross-linked polydimethylsiloxane (PDMS) elastic microchannel filled with 1% cross-linked viscous PDMS liquid (patterned bilayer). During peeling, we explored cavity shape as a function of microchannel dimensions and correlated the dimensionless cavity shape factor (CSF) and characteristic stress decay length, K-1. The peel test on the liquid-filled elastic microchannel shows three distinct cavity-shape regimes, elliptical, circular, and binary, based on the values of CSF and K-1. Such cavity formation and shape regimes could be important for improving the design of pressure-sensitive adhesives.
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Hyaluronidase (hyase) is a glycosidase enzyme that predominantly degrades hyaluronic acid (HA) having important applications in many biotechnological processes and therapeutics. Several assay methods have been proposed to screen hyase producing microorganisms; however, they rely on unique reagents and sophisticated instruments, which are expensive and could be unavailable in general laboratories. In the present studies, a rapid, simple, sensitive, highly reproducible, and cost-effective qualitative plate assay has been developed for the screening of hyase producing microorganisms. The routinely used plate assay method of Richman and Baer requires a special chemical cetylpyridinium chloride and long incubation period of 20 h; but still, the zones of clearance are not very clear and distinct. While, the present method requires an incubation period of only 1 h and the distinct zones of clearance appear with Gram's iodine within 1 min of time. This method does not require any special medium, unlike previously reported methods. Moreover, use of commonly available Gram's iodine makes this method suitable for many researchers. The results of the assay method were validated by TLC, zymographic analysis and determining the growth of isolates in minimal medium containing HA as a sole carbon source.
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Pruebas de Enzimas/métodos , Hialuronoglucosaminidasa/aislamiento & purificación , Streptococcus equi/enzimología , Medios de Cultivo/química , Pruebas de Enzimas/economía , Humanos , Ácido Hialurónico/aislamiento & purificación , Ácido Hialurónico/metabolismo , Hialuronoglucosaminidasa/metabolismo , Yodo , Sensibilidad y Especificidad , Sefarosa , Streptococcus equi/química , Streptococcus equi/crecimiento & desarrollo , Streptococcus mitis/enzimologíaRESUMEN
CTX-M-140, a novel CTX-M-type extended-spectrum ß-lactamase (ESBL), was identified in cephalosporin-resistant clinical isolates of Proteus mirabilis CTX-M-140 contained an alanine-to-threonine substitution at position 109 compared to its putative progenitor, CTX-M-14. When it was expressed in an Escherichia coli isogenic background, CTX-M-140 conferred 4- to 32-fold lower MICs of cephalosporins than those with CTX-M-14, indicating that the phenotype was attributable to this single substitution. For four mutants of CTX-M-14 that were constructed by site-directed mutagenesis (A109E, A109D, A109K, and A109R mutants), MICs of cephalosporins were similar to those for the E. coli host strain, which suggested that the alanine at position 109 was essential for cephalosporin hydrolysis. The kinetic properties of native CTX-M-14 and CTX-M-140 were consistent with the MICs for the E. coli clones. Compared with that of CTX-M-14, a lower hydrolytic activity against cephalosporins was observed for CTX-M-140. blaCTX-M-140 is located on the chromosome as determined by I-CeuI pulsed-field gel electrophoresis (I-CeuI-PFGE) and Southern hybridization. The genetic environment surrounding blaCTX-M-140 is identical to the sequence found in different plasmids with blaCTX-M-9-group genes among the Enterobacteriaceae Genome sequencing and analysis showed that P. mirabilis strains with blaCTX-M-140 have a genome size of â¼4 Mbp, with a GC content of 38.7% and 23 putative antibiotic resistance genes. Our results indicate that alanine at position 109 is critical for the hydrolytic activity of CTX-M-14 against oxyimino-cephalosporins.
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Sustitución de Aminoácidos , Antibacterianos/metabolismo , Cefalosporinas/metabolismo , Genoma Bacteriano , Proteus mirabilis/enzimología , beta-Lactamasas/genética , Alanina/metabolismo , Antibacterianos/farmacología , Composición de Base , Cefalosporinas/farmacología , Clonación Molecular , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Tamaño del Genoma , Hidrólisis , Isoenzimas/genética , Isoenzimas/metabolismo , Pruebas de Sensibilidad Microbiana , Mutación , Proteus mirabilis/efectos de los fármacos , Proteus mirabilis/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Treonina/metabolismo , beta-Lactamasas/metabolismoRESUMEN
mPGES-1 is inducible terminal synthase acting downstream of COX enzymes in arachidonic acid pathway, regulates the biosynthesis of pro-inflammatory prostaglandin PGE2. Cardiovascular side effect of coxibs and NSAIDs, selective for COX-2 inhibition, stimulated interest in mPGES-1, a therapeutic target with potential to deliver safe and effective anti-inflammatory drugs. The synthesis and structure activity relationship of a series of compounds from 2-aryl substituted quinazolin-4(3H)-one, pyrido[4,3-d]pyrimidin-4(3H)-one and pyrido[2,3-d]pyrimidin-4(3H)-one scaffolds as mPGES-1 inhibitor are discussed. A set of analogs (28, 48, 49) were identified with <10nM potencies in the recombinant human mPGES-1 enzyme and in the A549 cellular assays. These analogs were also found to be potent in the human whole blood assay (<400 nM). Furthermore, the representative compound 48 was shown to be selective with other prostanoid synthases and was able to effectively regulate PGE2 biosynthesis in clinically relevant inflammatory settings, in comparison with celecoxib.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Oxidorreductasas Intramoleculares/antagonistas & inhibidores , Pirimidinonas/farmacología , Quinazolinonas/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Oxidorreductasas Intramoleculares/metabolismo , Estructura Molecular , Prostaglandina-E Sintasas , Pirimidinonas/síntesis química , Pirimidinonas/química , Quinazolinonas/síntesis química , Quinazolinonas/química , Relación Estructura-ActividadRESUMEN
Otitis externa is an inflammatory and infectious disease that affects the external auditory canal. The term otorrhea refers to the outflow of discharge from the ear which is one of the main symptoms of otitis externa along with inflammation. External ear canal pathology or middle ear illness with tympanic membrane perforation is the etiological factor of otorrhea. Otorrhea is an indication of infection. Antimicrobial agents are the conventional treatment of various bacterial and fungal infections, but they have impediments such as resistance development, side effects, patient affordability, etc. The Gandhak Rasayana formulation mentioned in the Ayurvedic text can be a good option for the treatment of various infectious diseases. Karnasrava is a type of ear disease referred to as Vata predominant Tridoshaja disease and it is curable. The term Karnasrava signifies discharge from ear and is self-explanatory. Karnasrava consists of a wide spectrum of diseases and can have a near correlation with otitis externa as per signs and symptoms. Gandhak Rasayana exhibited significant antibacterial, antifungal and anti-inflammatory activity in otitis externa. Evaluating its antibacterial and antifungal activity can provide scientific evidence for the study through the present case report. A 31-year-old male patient registered in OPD at Sane Guruji Hospital, Hadapsar, Pune was clinically diagnosed as Karnasrava (Otitis externa) and pus culture positive for Klebsiella species. We started the treatment with Gandhak Rasayana-an Ayurvedic formulation of 250mg two tablets in the morning and evening with lukewarm water for 21 days. The outcome of the treatment was observed as a reduction in Karnashula (otalgia), Karnasrava (ear discharge), Karnakandu (itching), ear blockage and inflammatory changes. Post-treatment culture was negative for the organism. The improvement was noted in Brighton grading scale from grade III to grade I. Gandhak Rasayana showed significant antibacterial activity in the present case. Evaluating its antibacterial, antifungal and anti-inflammatory activity can provide scientific evidence for the study.