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A photoredox approach for synthesizing sulfur-substituted analogues of isocytosine via coupling of modular phenyl propargyl chloride with thiourea has been reported. The resulting product with an amine group was found amenable to various late-stage modifications, providing access to a broad range of sulfur-containing isocytosine derivatives.
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Persistent water contaminants include a variety of substances that evade natural cleaning processes posing severe risks to ecosystems. Their adsorptive elimination is a key approach to safer attenuation. Herein we present the design and development of Prussian blue incorporated polypyrrole (PPY/PB) hybrid nanocomposite as a high-performance adsorbent for the elimination of malachite green (M.G.), isoniazid (INH) and 4-nitrophenol (4-NP) water contaminants. The nanocomposite synthesis was favored by strong dopant-polymer interactions, leading to a PPY/PB material with enhanced electro-active surface area compared to pristine PPY. The structure-activity response of the nanocomposite for the adsorption of target contaminants was unveiled by evaluating its maximum adsorption capacities under environmentally viable conditions. In-depth analysis and optimization of adsorption influencing factors (pH, temperature, and adsorbent dose) were performed. Using equilibrium studies, kinetic model fitting, aided with FTIR analysis, a multi-step mechanism for the adsorption of target contaminants on the nanocomposite was proposed. Furthermore, the PPY/PB nanocomposite also acts as a catalyst, enabling contaminant elimination following a synergistic scheme that was demonstrated using 4-NP contaminant. The synergetic adsorption and catalytic degradation of 4-NP using PPY/PB as adsorbent and catalyst was demonstrated in the presence of NaBH4 as a reducing agent in absence of light. In summary, this work highlights the targeted design of adsorbent, its optimization for adsorptive avidity, and the synergistic role of adsorption trapping in the catalytic degradation of persistent contaminants.
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We have developed a visible-light-driven method for thioester synthesis that relies on the unique dual role of thiobenzoic acids as one-electron reducing agents and reactants leading to the formation of sulfur radical species. This synthetic process offers a wide scope, accommodating various thioacid and thiol substrates without the need for a photocatalyst.
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Building energy management systems (BEMS) are integrated computerized systems that track and manage the energy use of many pieces of building-related machinery and equipment, including lighting, power systems, and HVAC systems. Modern buildings must have BEMSs in order to reduce energy usage while maintaining comfort. Not only for energy-saving purposes, BEMS is essential in enhancing the quality of the energy supply, which helps to gain a better understanding of how energy is used and the building's energy usage. When the dynamics of a building's energy usage are known, it is possible to determine which changes are most likely to reduce consumption. Numerous connected devices, operating modes, energy usage, and environmental factors can all be monitored and controlled in real-time using BEMS. Changing operating times and setting points to maximize comfort and efficiency is made simple by this. In this paper, we have primarily addressed the two significant issues of model optimization and electricity consumption forecasts. Future forecasting has been done using the LSTM based time series approach. We generated data on the amount of electricity consumed by a hospital facility and tested our suggested methodologies on actual data. The findings gained demonstrated that the strategies were successful with both types of data. On actual data, the trend in electricity consumption can be accurately predicted. Several model optimizers enhanced the suggested methods' performance as well. Our objective function gain accuracy result of 95%.
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HER2 is the membrane receptor tyrosine kinase showing overexpression in several human malignancies, particularly breast cancer. HER2 overexpression causes the activation of Ras- MAPK and PI3K/Akt/ NF-κB cellular signal transduction pathways that lead to cancer development and progression. HER2 is, therefore, presumed as one of the key targets for the development of tumor-specific therapies. Several preclinical have been developed that function by inhibiting the HER2 tyrosine kinase activity through the prevention of the dimerization process. Most HER2 inhibitors act as ATP competitors and prevent the process of phosphorylation, and abort the cell cycle progression and proliferation. In this review, the clinical drug candidates and potent pre-clinical newly developed molecules are described, and the core chemical scaffolds typically responsible for anti-HER2 activity are deciphered. In addition, the monoclonal antibodies that are either used in monotherapy or in combination therapy against HER2-positive cancer are briefly described. The identified key moieties in this study could result in the discovery of more effective HER2-targeted anticancer drug molecules and circumvent the development of resistance by HER2-specific chemotherapeutics in the future.
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Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Fosfatidilinositol 3-Quinases/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Descoberta de Drogas , Linhagem Celular Tumoral , Resistencia a Medicamentos AntineoplásicosRESUMO
A mild electron donor-acceptor complex-mediated approach for the synthesis of N-acyl-N,O-hemiacetals has been reported. The key feature of this protocol is that it allows for direct access to electrophilic N-acylimines at room temperature without prefunctionalization of the hydroxyl group. The in situ generated N-acylimine can react with different nucleophiles, viz., alcohols, thiols, and nitriles, to afford a diverse range of scaffolds such as N,O-, N,S-, and N,N-acetals.
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In this work, 1-(4-bromophenyl)-2a,8a-dihydrocyclobuta[b]naphthalene-3,8dione (1-(4-BP)DHCBN-3,8-D) has been characterized by single crystal X-ray to get it's crystal structure with R(all data) - R1 = 0.0569, wR2 = 0.0824, 13C and 1HNMR, as well as UV-Vis and IR spectroscopy. Quantum chemical calculations via DFT were used to predict the compound structural, electronic, and vibrational properties. The molecular geometry of 1-(4-BP)DHCBN-3,8-Dwas optimized utilizing the B3LYP functional at the 6-311++G(d,p) level of theory. The Infrared spectrum has been recorded in the range of 4000-550 cm-1. The Potential Energy Distribution (PED) assignments of the vibrational modes were used to determine the geometrical dimensions, energies, and wavenumbers, and to assign basic vibrations. The UV-Vis spectra of the titled compound were recorded in the range of 200-800 nm in ACN and DMSO solvents. Additionally, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gap and electronic transitions were determined using TD-DFT calculations, which also simulate the UV-Vis absorption spectrum. Natural Bond Orbital (NBO) analysis can be used to investigate electronic interactions and transfer reactions between donor and acceptor molecules. Temperature-dependent thermodynamic properties were also calculated. To identify the interactions in the crystal structure, Hirshfeld Surface Analysis was also assessed. The Molecular Electrostatic Potential (MEP) and Fukui functions were used to determine the nucleophilic and electrophilic sites. Additionally, the biological activities of 1-(4-BP)DHCBN-3,8-D were done using molecular docking. These results demonstrate a significant therapeutic potential for 1-(4-BP)DHCBN-3,8-D in the management of Covid-19 disorders. Molecular Dynamics Simulation was used to look at the stability of biomolecules.
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A mild photoredox approach enabling the first one-step synthesis of thiolated 2-aminothiazoles has been reported. Notably, the incorporation of thio group on electron-rich heteroarenes such as aminothiazoles via conventional nucleophilic aromatic substitution (SNAr) presents a significant challenge owing to polarity mismatch. Herein, we present a remarkable site-selective installation of thio group at the C-5 position of the electron-rich aminothiazole skeleton and successfully used them for the postfunctionalization of drugs and natural products.
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Alcinos , Tiazóis , ElétronsRESUMO
Coordination compounds as dopants to conducting polymers combine desirable properties of individual components for a synergistic effect. Prussian red (PR) a low spin iron (III) coordination compound was doped in polythiophene (PTP) matrix to explore propensity of this inorganic-organic hybrid composite material towards wastewater treatment. PR doping was observed to improve mechano, thermal, electrical, and photocatalytic attributes of pure PTP. PTP/PR composite characterization was attempted using the powder X-ray diffraction, TEM, TGA, FTIR, BET analysis and UV-Visible spectroscopy. Optimization of adsorption conditions, adsorbent regeneration, adsorption thermodynamics studies of PTP/PR were carried out using malachite green (MG) dye as a model system. Under optimized conditions 92% MG dye adsorption was observed over 20 mg PTP/PR nanocomposite in 20 minutes at pH 7. PTP/PR nanocomposite also demonstrated a complimentary performance with real wastewater samples. Thermodynamic studies indicate spontaneous process with electrostatic attraction as the predominant noncovalent interaction. This study highlights designing catalysts capable of synergistic adsorption and photocatalytic activities for effective wastewater treatment.
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Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Ferro , Cinética , Polímeros , Pós , Corantes de Rosanilina , Termodinâmica , Tiofenos , Águas Residuárias/químicaRESUMO
A photoredox thioformylation of terminal alkynes using nitromethane as a formyl anion equivalent, thereby leading to the synthesis of (E)-1,2-difunctionalized acrylaldehyde, has been described. The current strategy introduces an adaptable aldehyde function across an alkyne and offers a new route to synthesizing α-alkyl/aryl aldehydes.
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Objectives: To compare the outcome prophylactic antibiotics and routine pre-surgical and post-surgical in terms of incidence of surgical site infection (SSI) and to explore the effect of various factors such as duration of surgery and patient characteristics (if any). Methods: A double-blinded prospective analysis of a total of 60 patients with the primary inguinal hernia was conducted from 24th August 2020 to 24th August 2021 at the Surgical Department of Nishtar Medical University & Hospital, Multan. The participants of the study were categorized into two groups such that 30 consecutive patients were placed in the study group who were administered with a single dose of prophylactic antibiotic 30 minutes before to mesh repair surgery and the remaining 30 patients were placed in the control group who were administered routine antibiotics pre and post-operatively. The effects in patients were observed till 30 days following surgery for any sign of infection. All the collected data were analyzed through SPSS (version 19). Results: The rate of infection in both groups was noted. The incidence of infection in the study group (13.3%) was higher as compared to the control group (10%). No patient underwent mesh removal and no significant difference in terms of post-operative complications was observed in the results of both groups. Conclusion: Both the treatments, prophylactic antibiotics and routine pre-surgical and post-surgical were equally effective. However, we recommend the administration of prophylactic since they are cost-effective and prevent bacterial drug resistance.
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A photoredox approach enabling one-step synthesis of oxazetidines with a free -NH group via the combined use of alkyne, thiophenol, and azide has been reported. The synthesized oxazetidine with the free -NH group was stable enough for various late-stage transformations such as methylation, acetylation, tosylation, and ring-opening reaction to afford synthetically useful α-aminoketones.
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Alcinos , Azidas , Catálise , OxirreduçãoRESUMO
Sustainable agricultural production is critically antagonistic by fluctuating unfavorable environmental conditions. The introduction of mineral elements emerged as the most exciting and magical aspect, apart from the novel intervention of traditional and applied strategies to defend the abiotic stress conditions. The silicon (Si) has ameliorating impacts by regulating diverse functionalities on enhancing the growth and development of crop plants. Si is categorized as a non-essential element since crop plants accumulate less during normal environmental conditions. Studies on the application of Si in plants highlight the beneficial role of Si during extreme stressful conditions through modulation of several metabolites during abiotic stress conditions. Phytohormones are primary plant metabolites positively regulated by Si during abiotic stress conditions. Phytohormones play a pivotal role in crop plants' broad-spectrum biochemical and physiological aspects during normal and extreme environmental conditions. Frontline phytohormones include auxin, cytokinin, ethylene, gibberellin, salicylic acid, abscisic acid, brassinosteroids, and jasmonic acid. These phytohormones are internally correlated with Si in regulating abiotic stress tolerance mechanisms. This review explores insights into the role of Si in enhancing the phytohormone metabolism and its role in maintaining the physiological and biochemical well-being of crop plants during diverse abiotic stresses. Moreover, in-depth information about Si's pivotal role in inducing abiotic stress tolerance in crop plants through metabolic and molecular modulations is elaborated. Furthermore, the potential of various high throughput technologies has also been discussed in improving Si-induced multiple stress tolerance. In addition, a special emphasis is engrossed in the role of Si in achieving sustainable agricultural growth and global food security.
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The activation of caspases is central to apoptotic process in living systems. Defects in apoptosis have been implicated with carcinogenesis. Need to develop smart agents capable of inducing apoptosis in tumor cells is obvious. With this motive, diversity oriented synthesis of 1-benzylpyrrolidin-3-ol analogues was envisaged. The multi component Ugi reaction synthesized library of electronically diverse analogues was explored for cytotoxic propensity towards a panel of human cancer cell lines at 10 µM. The lead compounds exhibit a selective cytotoxicity towards HL-60 cells as compared to cell lines derived from solid tumors. Besides, their milder cytotoxic effect on non-cancerous cell lines reaffirm their selective action towards cancer cells only. The lead molecules were tested for their ability to target caspase-3, as a vital protease triggering apoptosis. The lead compounds were observed to induce apoptosis in HL-60 cells around 10 µM concentration. The lead compounds exhibited various non-covalent supra type interactions with caspase-3 key residues around the active site. The binding ability of lead compounds with caspase-3 was studied via molecular docking and molecular dynamic (MD) simulations. MD simulations indicated the stability of compound-caspase-3 complex throughout the 50 ns simulation run. The stability and bio-availability of the lead compounds under physiological conditions was assessed by their interaction with Bovine Serum Albumin (BSA) as model protein. BSA interactions of lead compounds were studied by various bio-physical methods and further substantiated with in silico MD simulations.
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Antineoplásicos/farmacologia , Caspase 3/metabolismo , Ativadores de Enzimas/farmacologia , Pirrolidinas/farmacologia , Animais , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Ativadores de Enzimas/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Pirrolidinas/metabolismo , Soroalbumina Bovina/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
A visible-light-mediated site-selective oxidative annulation of naphthols with alkynes for the synthesis of functionalized naphthofurans has been developed. The reaction relies on the in situ formation of an electron donor acceptor pair between phenylacetylene and thiophenol as the light-absorbing system to obviate the requirement of an added photocatalyst. The protocol facilitates the transformation of 1-naphthol and 2-naphthol as well as 1,4-naphthoquinone into a wide variety of highly functionalized naphthofurans.
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Alcinos , Naftóis , Catálise , Estrutura Molecular , Estresse OxidativoRESUMO
COVID-19 spread worldwide after its outbreak in December 2019. This review paper aims to educate the readers regarding SARS-CoV-2 diagnostic and detection tools and the issues experienced by researchers. We identify on-the-horizon point-of-care diagnostic tests and inspire scholars to develop their innovations past conception. It will also effectively avoid potential pandemics to establish plug-and-play diagnostic information to handle the SARS infection. The authors agree that arbitrary-access, interconnected systems with flexible functionality accessible at the point-of-care, would enable fast and precise diagnosis and tracking.
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COVID-19/diagnóstico , Animais , Teste para COVID-19/métodos , Reações Falso-Positivas , Humanos , Pandemias/prevenção & controle , SARS-CoV-2/patogenicidadeRESUMO
Acetylcholinesterase (AChE) inhibitors are actively used for the effective treatment of Alzheimer's disease. In recent years, the neuroprotective effects of organoselenium compounds such as ebselen and diselenides on the AChE activity have been investigated as potential therapeutic agents. In this work, we have carried out systematic kinetic and intrinsic fluorescence assays in combination with docking and molecular dynamics (MD) simulations to elucidate the molecular mechanism of the mixed inhibition of AChE by ebselen and diphenyl diselenide (DPDSe) molecules. Our MD simulations demonstrate significant heterogeneity in the binding modes and allosteric hotspots for DPDSe on AChE due to non-specific interactions. We have further identified that both ebselen and DPDSe can strongly bind around the peripheral anionic site (PAS), leading to non-competitive inhibition similar to other PAS-binding inhibitors. We also illustrate the entry of the DPDSe molecule into the gorge through a "side door", which offers an alternate entry point for AChE inhibitors as compared to the usual substrate entry point of the gorge. Together with results from experiments, these simulations provide mechanistic insights into the mixed type of inhibition for AChE using DPDSe as a promising inhibitor for AChE.
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Inibidores da Colinesterase , Compostos Organosselênicos , Acetilcolinesterase/metabolismo , Sítios de Ligação , Inibidores da Colinesterase/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica MolecularRESUMO
BACKGROUND: Reducing immunosuppression can effectively treat BK viremia (BKV) and BK nephropathy, but has been associated with increased risks for acute rejection and development of donor-specific antibodies (DSA). To date there have been no systematic evaluations of re-escalating immunosuppression in transplant patients with resolving BKV. Importantly, the safety of this approach and impact on graft survival is unclear. METHODS: We performed a single-center retrospective review of kidney transplant recipients between July 2011 and June 2013 who had immunosuppression reduction after developing BKV (plasma PCR ≥ 1000 copies/ml). Changes in immunosuppression and patient outcomes were tracked until occurrence of a complication event: biopsy-proven acute rejection (BPAR), detection of de novo DSA, or recurrent BKV. Patients were grouped according to whether or not net immunosuppression was eventually increased. RESULTS: Out of 88 patients with BKV, 44 (50%) had net immunosuppression increased while the other 44 did not. Duration of viremia, peak viremia, induction, and sensitization status were similar between the two groups. In a Kaplan-Meier analysis, increasing immunosuppression was associated with less BPAR (P = .001) and a trend toward less de novo DSA development (P = .06). Death-censored graft survival (P = .27) was not different between the two groups. In the net immunosuppression increase group, recurrent BKV occurred in 22.7% without any BKV-related graft losses. CONCLUSION: These findings support potential benefits of increasing immunosuppression in patients with low-level or resolved BKV, but prospective trials are needed to better understand such an approach.
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Vírus BK , Infecções por Polyomavirus , Humanos , Terapia de Imunossupressão , Imunossupressores , Transplante de Rim , Estudos Prospectivos , Estudos Retrospectivos , Infecções Tumorais por VírusRESUMO
A photoredox-mediated protocol for the synthesis of α-alkoxy-ß-ketosulfoxides and α,ß-dialkoxysulfoxides using alkynes, thiol, and alcohols is reported. This work presents a rare single-step synthesis of α-substituted sulfoxides, involving tandem introduction of a thiol and alcohol as a key enabling advancement. Furthermore, the method can be easily employed to access vinyl sulfoxides and ß-ketosulfoxides.
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Japanese encephalitis virus, a neurotropic flavivirus, causes sporadic encephalitis with nearly 25% fatal case reports. JEV infects neural stem/progenitor cells (NSPCs) and decreases their proliferation. Statin, a commonly used class of cholesterol lowering drug, has been shown to possess potent anti-inflammatory and neuroprotective effects in acute brain injury and chronic neurodegenerative conditions. Here, we aimed to check the efficacy of atorvastatin in alleviating the symptoms of Japanese encephalitis (JE). Using BALB/c mouse model of JEV infection, we observed that atorvastatin effectively reduces viral load in the subventricular zone (SVZ) of infected pups and decreases the resultant cell death. Furthermore, atorvastatin abrogates microglial activation and production of proinflammatory cyto/chemokine production post JEV infection in vivo. It also reduced interferon-ß response in the neurogenic environs. The neuroprotective role of atorvastatin is again evident from the rescued neurosphere size and decreased cell death in vitro. It has also been observed that upon atorvastatin administration, cell cycle regulatory proteins and cell survival proteins are also restored to their respective expression level as observed in uninfected animals. Thus the antiviral, immunomodulatory and neuroprotective roles of atorvastatin reflect in our experimental observations. Therefore, this drug broadens a path for future therapeutic measures against JEV infection.