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The COVID-19 pandemic highlights an urgent need for effective antivirals. Targeting host processes co-opted by viruses is an attractive antiviral strategy with a high resistance barrier. Picolinic acid (PA) is a tryptophan metabolite endogenously produced in mammals. Here, we report the broad-spectrum antiviral activity of PA against enveloped viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus (IAV), flaviviruses, herpes simplex virus, and parainfluenza virus. Mechanistic studies reveal that PA inhibits enveloped virus entry by compromising viral membrane integrity, inhibiting virus-cellular membrane fusion, and interfering with cellular endocytosis. More importantly, in pre-clinical animal models, PA exhibits promising antiviral efficacy against SARS-CoV-2 and IAV. Overall, our data establish PA as a broad-spectrum antiviral with promising pre-clinical efficacy against pandemic viruses SARS-CoV-2 and IAV.
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COVID-19 , Vírus da Influenza A , Animais , Humanos , SARS-CoV-2/metabolismo , Internalização do Vírus , Pandemias , Replicação Viral , Antivirais/farmacologia , Antivirais/uso terapêutico , Mamíferos/metabolismoRESUMO
Chromium-doped calcium aluminozincate phosphor with a distinct amount of chromium was prepared via the sol-gel technique. The phase analysis and morphological study along with optical properties were conducted on the prepared material. The room temperature luminescent traits of the sample were studied in detail under 540 nm excitation wavelength. The deep red emission was confirmed from the CIE coordinates calculated using emission data. The decay curves were recorded to calculate the lifetime values for the aforementioned powder samples. The temperature-dependent luminescent characteristics were also investigated to identify the activation energy and thermal stability. The quantum yield was also calculated using luminescence spectra and found to be relatively good for the present phosphor. All of the investigated studies specified above signify that the synthesized phosphor is well suited as a red emitter in lighting and display devices.
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The substrate-induced effects on the polarizability (α) and first dipole hyperpolarizability (ß) of group-IV (i.e., graphene, silicene, germanene, stanene) and group-V (i.e., phosphorene, arsenene, antimonene, and bismuthene) elemental monolayer nanoflakes are investigated. Density functional theory calculations show that these monolayers are bound with varying degrees of interaction strength with the Ag(111) substrate surface. Calculated dipole moment and ß values are zero for the centrosymmetric configurations of the pristine elemental monolayers. On the other hand, substrate-induced changes in the electronic densities at the interface lead to substantially enhanced values of ß, making these materials attractive for applications in the next-generation photonic technologies at the nanoscale.
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Purpose: The aim of the study was to emphasize the compressive strength and flexural strength of glass-ionomer cement (GIC)-gold hybrid, conventional GIC, and resin-modified GIC (RMGIC). Methodology: Three GIC materials were used in the study: group A: GC-gold hybrid (Gold Label hybrid Universal Restorative), group B: type II conventional GIC, and group C: RMGIC. A total of 120 cylindrical test specimens of dimensions 4 mm diameter × 6 mm height were prepared from a custom-made Teflon mold according to respective study groups. The specimens prepared were then stored in 20 mL of deionized water at 37°C for 3 h daily for 30 days, and the solutions were changed every week, after which they were tested for compressive strength and flexural strength by using a universal force testing machine. All the results were analyzed by SPSS software and were subjected to statistical analysis using ANOVA followed by the Bonferroni post-hoc test. Results: The mean compressive strength was the highest for group A and lowest for group B. Similarly, the mean flexural strength was the highest for group A and lowest for group B. Conclusion: The conclusions can be drawn from this in-vitro study that the compressive strength and flexural strength of GC-gold hybrid were greater than those of RMGIC and conventional GIC.
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The anomalous origin of the left circumflex (Cx) artery (LCX) from the right coronary sinus or the right coronary artery (RCA) has been reported as one of the most common congenital coronary anomalies. However, the occurrence of double or twin Cx coronary arteries has been sparsely reported in the literature. We describe a rare case of a middle-aged male with acute myocardial infarction (MI) who had double Cx coronary arteries, one arising from the RCA and the other from the left main coronary artery. He underwent successful angioplasty with the stenting of the culprit right Cx artery (RCX).
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Coronavirus disease 2019 (COVID-19), although predominantly a respiratory illness, can have important cardiovascular implications, which include the development of myocardial injury/myocarditis, acute coronary syndromes, arrhythmias, pericarditis, and the occurrence of arterial and venous thrombosis. We describe a rare case of a middle-aged COVID-19 patient who developed sub-acute stent thrombosis after implantation of second-generation drug-eluting stents (DES) despite being adherent to dual antiplatelet therapy including ticagrelor and who subsequently developed multiple coronary artery aneurysms within a few weeks of the DES implantation.
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Isolated right ventricular myocardial infarction (RVMI) is a rare clinical presentation of acute coronary syndrome. A high index of suspicion is needed for its timely diagnosis and management to prevent serious complications like heart failure, cardiogenic shock, ventricular arrythmias or sudden cardiac death. Coronary anomalies are rare entities with a varied clinical presentation. We report an interesting case of a middle-aged female who presented with isolated RVMI, with a borderline blood pressure and sinus node dysfunction resulting from occlusion of an anomalous right coronary artery. The successful management of this patient with percutaneous coronary intervention using coronary stenting is also discussed.
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Angioplastia Coronária com Balão , Infarto Miocárdico de Parede Anterior , Infarto do Miocárdio , Intervenção Coronária Percutânea , Angioplastia Coronária com Balão/efeitos adversos , Infarto Miocárdico de Parede Anterior/complicações , Vasos Coronários , Feminino , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Intervenção Coronária Percutânea/efeitos adversosRESUMO
Pilot data on Hand hygiene (HH) compliance using a standard World Health Organisation checklist for 1-week suggested only 20% compliance. So, we planned a Quality Improvement study to improve HH compliance among health care providers in our Special Newborn Care Unit from 20% to 60% over 12 months. METHODS: We did this study in 3 phases: Baseline phase (2 months), Intervention phase (8 months), and Postintervention phase (2 months). A multidisciplinary Quality Improvement team composed of doctors, nursing staff, and ward attendants was constituted. The team analyzed potential barriers to HH by Fishbone analysis. Three trained observers randomly selected two target Special Newborn Care Unit patients daily and collected data on HH compliance unobtrusively during the three 8-h shifts over 24 h. In addition, we tested a range of interventions using multiple Plan Do Study Act cycles: Staff education; Displaying posters; Round the clock availability of soap and hand rub; Staff felicitation; Group performance feedback. We also collected data on healthcare-associated infections in all three phases. RESULTS: The total observations for HH during the baseline, intervention, and postintervention phase were 1488, 5808, and 1464, respectively. The HH compliance improved from 27.2% to 57.1% in the postintervention phase. There was no difference in the healthcare-associated infections among the three phases. CONCLUSIONS: The HH compliance rates improved significantly but not to the desired extent. So, we planned to increase our workforce, and improve our training program and infrastructure.
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MAIN CONCLUSION: Overexpression of forage sorghum oleosin genes in Arabidopsis oleosin-deficient mutant and yeast showed increased germination rate, triacylglycerol content, and protection against lipase-mediated TAG degradation. Plant lipids are an important source of ration for cattle or other livestock animals to fulfil their energy needs. Poor energy containing green forages are still one of the major sources of food for livestock animals, leaving the animals undernourished. This lowers the milk and meat production efficiency, thereby affecting human consumption. Oleosin, an essential oil body surface protein, is capable of enhancing and stabilizing the lipid content in plants. We identified and functionally characterized three forage sorghum oleosin genes (SbOle1, SbOle2, and SbOle3) in Arabidopsis and yeast. Phylogenetic analysis of SbOle proteins showed a close relationship with rice and maize oleosins. Expression analysis of SbOle genes determined a higher expression pattern in embryo followed by endosperm, while its expression in the non-seed tissues remained negligible. Overexpression of SbOle genes in Arabidopsis ole1-deficient mutants showed restoration of normal germination whereas control mutant seeds showed lower germination rates. Heterologous overexpression of SbOle in yeast cells resulted in increased TAG accumulation. Additionally, the TAG turnover assay showed the effectiveness of SbOle genes in reducing the yeast endogenous and rumen bacterial lipase-mediated TAG degradation. Taken together, our findings not only provide insights into forage sorghum oleosin for increasing the energy content in non-seed organs but also opened up the direction towards implication of oleosin in rumen protection of fodders.
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Proteínas de Arabidopsis , Arabidopsis , Sorghum , Animais , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Bovinos , Filogenia , Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética , Sementes/genética , Sorghum/genética , TriglicerídeosRESUMO
Vertically stacked, layered van der Waals (vdW) heterostructures offer the possibility to design materials, within a range of chemistries and structures, to possess tailored properties. Inspired by the naturally occurring mineral merelaniite, this paper studies a vdW heterostructure composed of a MoS2 monolayer and a PbS bilayer, using density functional theory. A commensurate 2D heterostructure film and the corresponding 3D periodic bulk structure are compared. The results find such a heterostructure to be stable and possess p-type semiconducting characteristics. Due to the heterostructure's weak interlayer bonding, its carrier mobility is essentially governed by the constituent layers; the hole mobility is governed by the PbS bilayer, whereas the electron mobility is governed by the MoS2 monolayer. Furthermore, we estimate the hole mobility to be relatively high (~106 cm2V-1s-1), which can be useful for ultra-fast devices at the nanoscale.
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Aim: To study sex-related differences in acute coronary syndrome (ACS) presentation, management and in-hospital outcomes. Materials & methods: We studied 621 ACS patients (150 women, 471 men) of low socio-economic status from South India from February 2015 to January 2016. Multivariable logistic regression methods were used to assess sex differences in the in-hospital outcomes. Adjudicated major adverse cardiovascular events (MACE) included in-hospital cardiac arrest, cardiogenic shock, heart failure, re-infarction, stroke, major bleeding and mortality. Results & conclusion: Mean age in women was 60.97 ± 11.23 years versus 54.5 ± 10.87 years in men (p < 0.001). Women had higher prevalence of hypertension and diabetes and presented with more non-ST elevation ACS. There were no differences in the use of antiplatelets, statins and other pharmacotherapy except for the higher use of nitrates in women. There were no differences in MACE rates between women and men (15.3 vs 9.6%; adjusted odds ratio: 1.43; CI: 0.76-2.69).
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Síndrome Coronariana Aguda , Síndrome Coronariana Aguda/epidemiologia , Idoso , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Caracteres Sexuais , Fatores Sexuais , Fatores Socioeconômicos , Resultado do TratamentoRESUMO
Flavivirus is a genus of medically important viruses, including Dengue virus (DENV), Zika virus (ZIKV), Yellow Fever virus (YFV), West Nile virus (WNV), Japanese encephalitis virus (JEV), etc. The global burden of these acute infection-causing viruses is ever-increasing. Primary febrile symptoms of most of these viruses can progress to hemorrhagic or neurological complications, and some like JEV, YFV have a greater than 15% mortality. The absence of antiviral therapy and highly effective vaccine candidates for these viruses highlights the need for research into virulence and immune evasion mechanisms at the molecular level. Interaction with the host needs to be carefully dissected to narrow down to a list of necessary factors for virus survival within the host. This review attempts to comprehensively compile research efforts made in the field of innate immune subversion strategies employed by the human Flaviviruses.
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Flavivirus , Infecção por Zika virus , Zika virus , Humanos , Evasão da Resposta Imune , Imunidade InataRESUMO
The nonlinear optical properties of van der Waals bilayer heterostructures composed of graphene/h-BN and graphene/phosphorene nanoflakes are investigated using time-dependent density functional theory. Our calculated results show a significant enhancement of the first-hyperpolarizability value, ß in heterostructures relative to the pristine nanoflakes at λ = 1064 nm. The calculated enhancement in optical nonlinearity mainly results from in-plane anisotropy induced by the interlayer electronic coupling between the adjacent nanoflake layers; a higher degree of anisotropy is induced by puckered phosphorene compared to atomically flat h-BN yielding χ (2) value corresponding to the second harmonic generation of â¼50 pm V-1 in the zigzag graphene/phosphorene bilayer heterostructure. The calculated results clearly show that graphene-based nanoflake heterostructures giving large NLO coefficients together with high electron mobility of these materials offer new opportunities as candidate materials of choice for next-generation photonics and integrated quantum technologies.
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Storage lipid mobilization by lipases and lipoxygenases (LOXs) in response to developmental cues take place during seed germination. After rice grain milling, the endogenous lipases and LOXs present in the bran fraction come in contact with the storage lipid reserve or triacylglycerol (TAG). Lipases catalyze the hydrolysis of TAGs to non-esterified fatty acids (NEFAs) and glycerol. The NEFAs, especially linoleic acid (18:2) produced, are further subjected to oxidative rancidity via peroxidation reaction catalyzed by LOXs. This results in the production of conjugated hydroperoxides of 18:2 that influence the off-flavors in rice bran lipids. The aim of this study is to understand how lipid mobilization and expression of lipase and LOX genes occur in the bran of germinating rice grains (Oryza sativavar. Pusa Basmati 1). Our results show that the primary source of storage lipids in bran is TAG, and its mobilization starts at 4 days after imbibition (4 DAI). Using publically available RNA-seq data and phylogeny analyses, we selected a total of 18 lipase and 16 LOX genes in rice for their expression profiles during onset of lipid mobilization. Gene expression analyses revealed OsLip1, OsLip9, and OsLip13; and OsLOX3 and OsLOX14 as the predominantly expressed genes in bran of germinating rice grains. This study explores two important events in the germinating rice grains, namely, mobilization of storage lipids and expression pattern of lipase and LOX genes. The information generated in this study can be used to efficiently manipulate the genes to enhance the shelf-stability of bran lipid reserve.
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Oryza , Germinação , Lipase/genética , Lipídeos , Lipoxigenase/genética , Lipoxigenases , Oryza/genéticaRESUMO
Electronic structure calculations based on density functional theory were performed to investigate structural, mechanical, and electronic properties of phosphorene-based large honeycomb dumbbell (LHD) hybrid structures and a new phosphorene allotrope, referred to as ψâ³-P. The LHD hybrids (i.e., X6P4; X being C or Si or Ge or Sn) and ψâ³-P have significantly higher bandgaps than the corresponding pristine LHD structures, except the case of C6P4, which is metallic. ψâ³-P is found to be a highly flexible p-type material which shows strain-engineered photocatalytic activity in a highly alkaline medium. The carrier mobility of the considered systems is as high as 105 cm2 V-1 s-1 (specifically the electron mobility of LHD structures). The calculated STM images display the surface morphologies of the LHD hybrids and ψâ³-P. The predicted phosphorus-based 2D structures with novel electronic properties may be candidate materials for nanoscale devices.
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Few-layer black phosphorene has recently attracted significant interest in the scientific community. In this paper, we consider several polymorphs of phosphorene nanoribbons (PNRs) and employ deformation potential theory within the effective mass approximation, together with density functional theory, to investigate their structural, mechanical and electronic properties. The results show that the stability of a PNR strongly depends on the direction along which it can be cut from its 2D counterpart. PNRs also exhibit a wide range of line stiffnesses ranging from 6 × 1010 eV m-1 to 18 × 1011 eV m-1, which has little dependence on the edge passivation. Likewise, the calculated electronic properties of PNRs show them to be either a narrow-gap semiconductor (E g < 1 eV) or a wide-gap semiconductor (E g > 1 eV). The carrier mobility of PNRs is found to be comparable to that of black phosphorene. Some of the PNRs show an n-type (p-type) semiconducting character owing to their higher electron (hole) mobility. Passivation of the edges leads to n-type â p-type transition in many of the PNRs considered. The predicted novel characteristics of PNRs, with a wide range of mechanical and electronic properties, make them potentially suitable for use in nanoscale devices.
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The van der Waals heterostructures of allotropes of phosphorene (α- and ß-P) with MoSe2 (H-, T-, ZT- and SO-MoSe2) are investigated in the framework of state-of-the-art density functional theory. The semiconducting heterostructures, ß-P/H-MoSe2 and α-P/H-MoSe2, form anti-type structures with type I and type II band alignments, respectively, whose bands are tunable with an external electric field. α-P/ZT-MoSe2 and α-P/SO-MoSe2 form ohmic semiconductor-metal contacts while the Schottky barrier in ß-P/T-MoSe2 can be reduced to zero by an external electric field to form ohmic contacts which is useful to realize high-performance devices. Simulated STM images of the given heterostructures reveal that α-P can be used as a capping layer to differentiate between various allotropes of underlying MoSe2. The dielectric response of the considered heterostructures is highly anisotropic in terms of lateral and vertical polarization. The tunable electronic and dielectric response of van der Waals phosphorene/MoSe2 heterostructures may find potential applications in the fabrication of optoelectronic devices.
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Alluvial aquifers of the agrarian state of Punjab of southwestern arid zone used for irrigation of rice crops are rich in arsenic concentration. In the present study, rice (Oryza sativa L.) crops were raised in pots in a greenhouse with a purpose to study whether selenium (Se) application was effective in ameliorating As uptake. The rice crop was irrigated with arsenic laced water (0, 2.5, 5.0, 10.0 µM As L-1) throughout the growing period, without and with selenium (0.05 and 0.10 mg kg-1) added through mustard biomass, grown ex situ in seleniferous soil. Arsenic uptake and dry matter yield in different parts of the rice crop were assayed after application of As alone and simultaneous supplementations (As + Se). An antagonistic interaction between Se and As was observed. Addition of As through irrigation water significantly reduced yield of rice grain, straw and root. However, subsequent addition of Se helped in mitigating the harmful effect of As and countered the yield reduction caused due to As toxicity. The effect of Se on dry matter yield was more pronounced at its higher dose (0.10 mg kg-1) as compared to its lower dose (0.05 mg kg-1). The presence of Se either alone or added along with As significantly reduced the As concentration and its uptake by different parts of rice and higher reduction in As concentration was observed with addition of the highest level of applied Se (0.10 mg kg-1). Our observations indicated that Se supplementation might be favourable to reduce As accumulation and toxicity in rice crops.
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Agricultura/métodos , Arsênio/metabolismo , Oryza/fisiologia , Selênio/metabolismo , Poluentes do Solo/metabolismo , Monitoramento Ambiental , Raízes de Plantas/efeitos dos fármacos , Solo , ÁguaRESUMO
Our main investigation in the present research was to developt and evaluate targeting ligand-anchored multiwalled carbon nanotubes (MWCNTs) as prospective targeted drug delivery system, with a special focus on the MWCNTs surface functionalization (FA-PEG bis-amine functionalized, carboxylated MWCNTs). In vitro release of 5-fluorouracil (5-FU) was studied at pH 7.4 phosphate buffer and 5.5 acetate buffer, which displayed initial faster followed by sustained release up to 900 min. Further, 5-FU/FA-PEG bis amine-MWCNTs was found to be long circulating, prolonged half-life and increased drug accumulation in target tissue.
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Sistemas de Liberação de Medicamentos/métodos , Fluoruracila , Nanotubos de Carbono/química , Avaliação Pré-Clínica de Medicamentos , Feminino , Fluoruracila/química , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Humanos , Células MCF-7RESUMO
We report the tailoring of the electronic structures of various structural phases of phosphorene (α-P, ß-P, γ-P and δ-P) based homo- and hetero-bilayers through in-plane mechanical strains, vertical pressure and transverse electric field by employing density functional theory. In-plane biaxial strains have considerably modified the electronic bandgap of both homo- and hetero-bilayers while vertical pressure induces metallization in the considered structures. The γ-P homo-bilayer structure showed the highest ultimate tensile strength (UTS â¼ 6.21 GPa) upon in-plane stretching. Upon application of a transverse electric field, the variation in the bandgap of hetero-bilayers was found to be strongly dependent on the polarity of the applied field which is attributed to the counterbalance between the external electric field and the internal field induced by different structural phases and heterogeneity in the arrangements of atoms of each surface of the hetero-bilayer system. Our results demonstrate that the electronic structures of the considered hetero- and homo-bilayers of phosphorene could be modified by biaxial strain, pressure and electric field to achieve the desired properties for future nano-electronic devices.