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Electrical conductivity is very important property of nanomaterials for using wide range of applications especially energy applications. Metal-organic frameworks (MOFs) are notorious for their low electrical conductivity and less considered for usage in pristine forms. However, the advantages of high surface area, porosity and confined catalytic active sites motivated researchers to improve the conductivity of MOFs. Therefore, 2D electrical conductive MOFs (ECMOF) have been widely synthesized by developing the effective synthetic strategies. In this article, we have summarized the recent trends in developing the 2D ECMOFs, following the summary of potential applications in the various fields with future perspectives.
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In the current study, the application of fluorescence spectroscopy along with the advanced statistical technique and confocal microscopy was investigated for the early detection of stripe rust infection in wheat grown under field conditions. The indigenously developed Fluorosensor fitted with LED, emitting monochromatic light was used that covered comparatively larger leaf area for recording fluorescence data thus presenting more reliable current status of the leaf. The examined leaf samples covered the entire range of stripe rust disease infection from no visible symptoms to the complete disease prevalence. The molecular changes were also assessed in the leaves as the disease progresses. The emission spectra mainly produce two fluorescence emission classes, namely the blue-green fluorescence (400-600 nm range) and chlorophyll fluorescence (650-800 nm range). The chlorophyll fluorescence region showed lower chlorophyll bands both at 685 and 735 nm in the asymptomatic (early diseased) and symptomatic (diseased) leaf samples than the healthy ones as a result of partial deactivation of PSII reaction centers. The 735 nm chlorophyll fluorescence band was either slight or completely absent in the leaf samples with lower to higher disease incidence and thus differentiate between the healthy and the infected leaf samples. The Hydroxycinnamic acids (caffeic and sinapic acids) showed decreasing trend, whereas the ferulic acid increased with the rise in disease infection. Peak broadening/shifting has been observed in case of ferulic acid and carotenes/carotenoids, with the increase in the disease intensity. While using the LEDs (365 nm), the peak broadening and the decline in the chlorophyll fluorescence bands could be used for the early prediction of stripe rust disease in wheat crop. The PLSR statistical techniques discriminated well between the healthy and the diseased samples, thus showed promise in early disease detection. Confocal microscopy confirmed the early prevalence of stripe rust disease infection in a susceptible variety at a stage when the disease is not detectable visually. It is inferred that fluorescence emission spectroscopy along with the chemometrics aided in the effective and timely diagnosis of plant diseases and the detected signatures provide the basis for remote sensing.
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Basidiomycota , Triticum , Espectrometría de Fluorescencia , Clorofila , Enfermedades de las PlantasRESUMEN
The rapid industrialization of the world is disparagingly manipulating our environment and natural ecosystem. The researchers are taking keen interest to invent novel material as photocatalyst for non-degradable organic pollutants. Solar energy-driven practices employing semiconductors are a novel approach towards wastewater remediation. Here in, we successfully synthesized a vigorous photocatalysts comprising of g-C3N4 and doped ZnO-W/M (M = Co, Ce, Yb, Sm) by co-precipitation followed by metals doping via calcination approach. The structural, morphological, and photocatalytic applications for organic pollutants of synthesized heterostructure nanocomposites were examined by XRD, FTIR, SEM, EDX and UV visible spectrophotometer. Diffraction peaks attributed to both g-C3N4 and ZnO-W were detected in the XRD spectra. The FTIR spectra also inveterate the formation of g-C3N4/ZnO-W/M composites. The SEM images reveal an agglomerated morphology and EDS analysis also confirmed close contact between g-C3N4, ZnO-W and doped metals. The abridged energy band gap of g-C3N4/ZnO-W/M (M = Ce, Yb, Sm, Co) nanocomposites calculated via Tauc plot are 2.68, 2.88, 3.24 and 3.29 eV respectively. Narrowing of bandgap is considered an imperative triumph for the degradation of industrial effluents. The photocatalytic activity was performed against four different dyes and follows the trend Ce > Yb > Sm > Co. The recyclability tests were carried out for different dyes and no substantial catalytic activity loss was observed even after the fourth experimental run, which proves that reported ternary heterojunctions exhibit high mechanical stability and reusability.The species trapping experiment exposed that generated h+ are the principal active specie for dye photodegradation reactions. This work disseminates a novel photocatalyst for the removal of synthetic dyes.
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Nanocompuestos , Óxido de Zinc , Óxido de Zinc/química , Ecosistema , Catálisis , Nanocompuestos/química , ColorantesRESUMEN
Fifth generation (5G) is a recent wireless communication technology in mobile networks. The key parameters of 5G are enhanced coverage, ultra reliable low latency, high data rates, massive connectivity and better support to mobility. Enhanced coverage is one of the major issues in the 5G and beyond 5G networks, which will be affecting the overall system performance and end user experience. The increasing number of base stations may increase the coverage but it leads to interference between the cell edge users, which in turn impacts the coverage. Therefore, enhanced coverage is one of the future challenging issues in cellular networks. In this survey, coverage enhancement techniques are explored to improve the overall system performance, throughput, coverage capacity, spectral efficiency, outage probability, data rates, and latency. The main aim of this article is to highlight the recent developments and deployments made towards the enhanced network coverage and to discuss its future research challenges.
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This Regular Feature is based on a PhD study assessing the level of health literacy among university students in Pakistan. A cross-sectional survey was carried out using the validated European Health Literacy Survey (HLS-EU-Q) and non-parametric tests used to analyse data with the aim of determining the influence of personal determinants on health literacy skills. The findings of the study concluded that the population had a low health literacy level with limited skills in accessing, understanding, appraising and applying information for health care. Gender, age, and native languages, all had a statistically significant influence on health literacy skills. Practical implications are presented for the role of university libraries in supporting the development of health literacy in their undergraduate student populations are presented, including the need for the provision of health information in native languages.
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Alfabetización en Salud , Humanos , Pakistán , Estudios Transversales , Prevalencia , Encuestas y Cuestionarios , EstudiantesRESUMEN
BACKGROUND: Computer aided diagnosis has gained momentum in the recent past. The advances in deep learning and availability of huge volumes of data along with increased computational capabilities has reshaped the diagnosis and prognosis procedures. OBJECTIVE: These methods are proven to be relatively less expensive and safer alternatives of the otherwise traditional approaches. This study is focused on efficient diagnosis of three very common diseases: lung cancer, pneumonia and Covid-19 using X-ray images. METHODS: Three different deep learning models are designed and developed to perform 4-way classification. Inception V3, Convolutional Neural Networks (CNN) and Long Short Term Memory models (LSTM) are used as building blocks. The performance of these models is evaluated using three publicly available datasets, the first dataset contains images for Lung cancer, second contains images for Covid-19 and third dataset contains images for Pneumonia and normal subjects. Combining three datasets creates a class imbalance problem which is resolved using pre-processing and data augmentation techniques. After data augmentation 1386 subjects are randomly chosen for each class. RESULTS: It is observed that CNN when combined with LSTM (CNN-LSTM) produces significantly improved results (accuracy of 94.5 %) which is better than CNN and InceptionV3-LSTM. 3,5, and 10 fold cross validation is performed to verify all results calculated using three different classifiersConclusions:This research concludes that a single computer-aided diagnosis system can be developed for diagnosing multiple diseases.
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COVID-19 , Aprendizaje Profundo , Neoplasias Pulmonares , Humanos , COVID-19/diagnóstico por imagen , Diagnóstico por Computador , Neoplasias Pulmonares/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Computadores , Prueba de COVID-19RESUMEN
The present study was aimed at measuring the concentration of aflatoxin M1 (AFM1) in the milk of Holstein Friesian cows, its effect on the milk quality and seasonal trends, as well as to investigate the efficacy of a commercial clay-based toxin binder. For this purpose, milk samples from dairy cows (n = 72) were collected and assayed for AFM1 before employing a clay-based toxin binder. The milk samples (n = 72) were collected from selected animals, revealing that 69.4% of the milk samples had AFM1 levels above the United States permissible limit (0.5 µg/kg). The incidence of AFM1 in milk during the winter and summer was 82.5% and 53.1%, respectively. Owing to the presence of AFM1, the level of milk fat, solids-not-fat, and protein were found to be low. Subsequently, the affected animals were divided into two groups, i.e., AFM1 positive control (n = 10) and the experimental group (n = 40). The experimental group of animals were fed the clay-based toxin binder at 25 g/animal/day. A progressive decrease of 19.8% in the AFM1 levels was observed on day 4 and on day 7 (53.6%) in the treatment group. Furthermore, the fat, solids-non-fat and protein increased significantly in the milk. In conclusion, a high level of AFM1 contamination occurs in the milk in Pakistan, affecting the quality of the milk production. Clay-based toxin binders may be used to ensure the milk quality and to protect the animal and consumer health.
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Enzootic bovine leucosis is caused by bovine leukaemia virus (BLV), a Deltaretrovirus belonging to the family Retroviridae. BLV causes huge economic losses to the dairy industry in the form of decreased milk production, premature culling, and poor reproductive performance of the animals. The aim of the present study was to determine the seroprevalence of BLV infection in buffalo in two districts of Punjab, Pakistan. A total of 384 samples were collected and analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA) to investigate the seroprevalence of BLV through the detection of the anti-BLV gp51 antibody. A predesigned data questionnaire proforma was employed to find out the association of risk factors with disease. Overall, 18.2% of buffaloes were seropositive for BLV in the study population. The results revealed a significant association (P < 0.05) of age with BLV infection. Furthermore, milk yield and pregnancy had a significant association with the seroprevalence of BLV infection in buffalo whereas no significant association was found with sex, breeding, and health status. Biochemical and oxidative stress markers revealed a significant decrease in liver enzymes alanine transaminase (ALT) and aspartate transaminase (AST), glutathione peroxidase (GPX), and superoxide dismutase (SOD) in seropositive animals as compared to healthy animals. It is concluded that BLV has a considerable prevalence in buffalo in Punjab, Pakistan and there is a dire need to investigate the disease epidemiology at both national and international levels and strategies should be developed to implement an effective control program.
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The rapid development of flexible and wearable optoelectronic devices, demanding the superior, reliable, and ultra-long cycling energy storage systems. But poor performances of electrode materials used in energy devices are main obstacles. Recently, single-atom catalysts (SACs) are considered as emerging and potential candidates as electrode materials for battery devices. Herein, we have discussed the recent methods for the fabrication of SACs for rechargeable metal-air batteries, metal-CO2 batteries, metal-sulfur batteries, and other batteries, following the recent advances in assembling and performance of these batteries by using SACs as electrode materials. The role of SACs to solve the bottle-neck problems of these energy storage devices and future perspectives are also discussed.
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The effect of Bacillus subtilis on the immune responses and morphometry of the immune organs was evaluated in broilers challenged with S. gallinarum. For this purpose, Salmonella-free birds (n = 240) were split into four groups with six replicates of ten birds each. Groups included an NC (negative control, non-infected + non-medicated), a PC-S (positive control, Salmonella-infected + non-medicated), an AT-S (Salmonella-infected + medicated with enrofloxacin), and a BS-S (Salmonella-infected + B. subtilis (2.0 × 1010 cfu/g; 0.1 g/kg) group. On day 21, the thickness of the thymus cortex and medulla, germinal centre area of the spleen, bursal follicular length and bursal follicular area increased (P < 0.05) in the BS-S when compared to the NC and PC-S groups. On day 35, the BS-S group exhibited a higher (P < 0.05) antibody titre against the Newcastle disease virus (NDV), and cortex of the thymus was thicker (P < 0.05) compared to the other groups. A decrease in the thymus medulla thickness, germinal area of the spleen and bursal follicular number were noted in the PC-S group when compared to the other treatment groups. In conclusion, the prophylactic use of B. subtilis type probiotics alleviated the stress resulting from a Salmonella gallinarum infection and improved the immune organs development and function in infected broilers.
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The structural evolution pattern and electronic properties of Lu-doped germanium anion clusters, LuGen- (n = 5-17), have been investigated using a global search method combined with a double hybrid density functional theory and by comparing the theoretical PES spectra with the experimental ones. It is found that, for the structural growth patterns, a Lu-linked configuration is preferred for n = 10-14 in which the Lu atom as a linker connects two Ge subclusters and a Lu-encapsulated Ge cage-like motif is preferred for n = 15-17. The simulated PES spectra agree with experimental ones, revealing that the current global minimum structures are the true minima. The properties such as relative stability, charge transfer, highest-energy occupied molecular orbital-lowest-energy unoccupied molecular orbital (HOMO-LUMO) gap, IR, Raman, and ultraviolet-visible (UV-vis) spectra have been evaluated. The results of IR and Raman spectra could provide additional ways to experimentally identify the structure of these clusters. The results of stability, HOMO-LUMO gap, and UV-vis spectra could make the LuGe16- cluster the most suitable building block for further development as a potential optoelectronic material.
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Heteroatom doping is considered an efficient strategy when tuning the electronic and structural modulation of catalysts to achieve improved performance towards renewable energy applications. Herein, we synthesized a series of carbon-based hierarchical nanostructures through the controlled pyrolysis of Co-MOF (metal organic framework) precursors followed by in situ phosphidation. Two kinds of catalysts were prepared: metal nanoparticles embedded in carbon nanotubes, and metal nanoparticles dispersed on the carbon surface. The results proved that the metal nanoparticles embedded in carbon nanotubes exhibit enhanced ORR electrocatalytic performance, owed to the enriched catalytic sites and the mass transfer facilitating channels provided by the hierarchical porous structure of the carbon nanotubes. Furthermore, the phosphidation of the metal nanoparticles embedded in carbon nanotubes (P-Co-CNTs) increases the surface area and porosity, resulting in faster electron transfer, greater conductivity, and lower charge transfer resistance towards ORR pathways. The P-Co-CNT catalyst shows a half-wave potential of 0.887 V, a Tafel slope of 67 mV dec-1, and robust stability, which are comparatively better than the precious metal catalyst (Pt/C). Conclusively, this study delivers a novel path for designing multiple crystal phases with improved catalytic performance for energy devices.
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Granulosa cells (GCs) are essential for follicular growth, development, and atresia. The orexin-A (OXA) neuropeptide is widely involved in the regulation of various biological functions. OXA selectively binds to orexin receptor type 1 (OX1R) and mediates all its biological actions via OX1R. This study aimed to explore the expression of OXA and OX1R and their regulatory role in GCs proliferation, cell cycle progression, apoptosis, oocyte maturation, and underlying molecular mechanisms of these processes and elucidate its novel signaling pathway. Western blotting and RT-qPCR showed that OXA and OX1R were expressed during different developmental stages of GCs, and siRNA transfection successfully inhibited the expression of OX1R at the translational and transcriptional levels. Flow cytometry revealed that OX1R knockdown upregulated GCs apoptosis and triggered S-phase arrest in cell cycle progression. RT-qPCR and Western blotting showed significantly reduced expression of Bcl-2 and elevated expression of Bax, caspase-3, TNF-α, and P21 in OX1R-silenced GCs. Furthermore, the CCK-8 assay showed that knockdown of OX1R suppressed GCs proliferation by downregulating the expression of PCNA, a proliferation marker gene, at the translational and transcriptional levels. Western blotting revealed that knockdown of OX1R resulted in a considerable decrease of the phosphorylation level of the AKT and ERK1/2 proteins, indicating that the AKT/ERK1/2 pathway is involved in regulating GCs proliferation and apoptosis. In addition, OX1R silencing enhanced the mRNA expression of GDF9 and suppressed the mRNA expression of BMP15 in mouse GCs. Collectively, these results reveal a novel regulatory role of OXA in the development of GCs and folliculogenesis by regulating proliferation, apoptosis, and cell cycle progression. Therefore, OXA can be a promising therapeutic agent for female infertility.
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Células de la Granulosa/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Orexinas/fisiología , Folículo Ovárico/citología , Folículo Ovárico/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Apoptosis/genética , Apoptosis/fisiología , Ciclo Celular/genética , Ciclo Celular/fisiología , Proliferación Celular/genética , Proliferación Celular/fisiología , Regulación hacia Abajo/genética , Femenino , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/fisiología , Sistema de Señalización de MAP Quinasas/genética , Ratones , Receptores de Orexina/genética , Receptores de Orexina/metabolismo , Orexinas/metabolismo , Folículo Ovárico/efectos de los fármacos , Cultivo Primario de CélulasRESUMEN
A series of new derivatives of 4-(2-chloroethyl)morpholine hydrochloride (5) were efficiently synthesized. Briefly, different aromatic organic acids (1a-f) were refluxed to acquire respective esters (2a-f) using conc. H2SO4 as catalyst. The esters were subjected to nucleophillic substitution by monohydrated hydrazine to acquire hydrazides (3a-f). The hydrazides were cyclized with CS2 in the presence of KOH to yield corresponding oxadiazoles (4a-f). Finally, the derivatives, 6a-f, were prepared by reacting oxadiazoles (4a-f) with 5 using NaH as activator. Structures of all the derivatives were elucidated through 1D-NMR EI-MS and IR spectral data. All these molecules were subjected to antibacterial and hemolytic activities and showed good antibacterial and hemolytic potential relative to the reference standards.
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Antibacterianos/química , Hemolíticos/química , Morfolinas/química , Oxadiazoles/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Hemolíticos/síntesis química , Hemolíticos/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Morfolinas/síntesis química , Morfolinas/farmacología , Oxadiazoles/síntesis química , Oxadiazoles/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Salmonella typhi/efectos de los fármacos , Espectrofotometría Infrarroja , Staphylococcus aureus/efectos de los fármacosRESUMEN
The activity of Rho-specific guanine nucleotide dissociation inhibitor α (RhoGDIα) is regulated by its own phosphorylation at different amino acid sites. These phosphorylation sites may have a crucial role in local Rho GTPases activation during cell migration. This paper is designed to explore the influence of phosphorylation on shear stress-induced spatial RhoGDIα activation. Based on the fluorescence resonance energy transfer biosensor sl-RhoGDIα, which was constructed to test the RhoGDIα activity in living cells, new RhoGDIα phosphomimetic mutation (sl-S101E/S174E, sl-Y156E, sl-S101E, sl-S174E) and phosphorylation-deficient mutation (sl-S101A/S174A, sl-Y156A, sl-S101A, sl-S174A) biosensors were designed to test their effects on RhoGDIα activation upon shear stress application in human umbilical vein endothelial cells (HUVECs). The results showed lower RhoGDIα activity at the downstream of HUVECs (the region from the edge of the nucleus to the edge of the cell along with the flow). The overall decrease in RhoGDIα activity was inhibited by Y156A-mutant, whereas the polarized RhoGDIα and Rac1 activity were blocked by S101A/S174A mutant. It is concluded that the Tyr156 phosphorylation mainly mediates shear stress-induced overall RhoGDIα activity, while Ser101/Ser174 phosphorylation mediates its polarization. This study demonstrates that differential phosphorylation of RhoGDIα regulates shear stress-induced spatial RhoGDIα activation, which could be a potential target to control cell migration.
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Fosforilación/fisiología , Inhibidor alfa de Disociación del Nucleótido Guanina rho/metabolismo , Línea Celular , Movimiento Celular/fisiología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Proteína de Unión al GTP rac1/metabolismoRESUMEN
Novel bi-heterocyclic benzamides were synthesized by sequentially converting 4-(1H-indol-3-yl)butanoic acid (1) into ethyl 4-(1H-indol-3-yl)butanoate (2), 4-(1H-indol-3-yl)butanohydrazide (3), and a nucleophilic 5-[3-(1H-indol-3-yl)propyl]-1,3,4-oxadiazole-2-thiol (4). In a parallel series of reactions, various electrophiles were synthesized by reacting substituted anilines (5a-k) with 4-(chloromethyl)benzoylchloride (6) to afford 4-(chloromethyl)-N-(substituted-phenyl)benzamides (7a-k). Finally, the nucleophilic substitution reaction of 4 was carried out with newly synthesized electrophiles, 7a-k, to acquire the targeted bi-heterocyclic benzamides, 8a-k. The structural confirmation of all the synthesized compounds was done by IR, 1 H NMR, 13 C NMR, EI-MS, and CHN analysis data. The inhibitory effects of these bi-heterocyclic benzamides (8a-k) were evaluated against alkaline phosphatase, and all these molecules were identified as potent inhibitors relative to the standard used. The kinetics mechanism was ascribed by evaluating the Lineweaver-Burk plots, which revealed that compound 8b inhibited alkaline phosphatase non-competitively to form an enzyme-inhibitor complex. The inhibition constant Ki calculated from Dixon plots for this compound was 1.15 µM. The computational study was in full agreement with the experimental records and these ligands exhibited good binding energy values. These molecules also exhibited mild cytotoxicity toward red blood cell membranes when analyzed through hemolysis. So, these molecules might be deliberated as nontoxic medicinal scaffolds to render normal calcification of bones and teeth.
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Fosfatasa Alcalina/antagonistas & inhibidores , Benzamidas/síntesis química , Inhibidores Enzimáticos/síntesis química , Animales , Benzamidas/química , Benzamidas/farmacología , Benzamidas/toxicidad , Bovinos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/toxicidad , Membrana Eritrocítica/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Cinética , Ligandos , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Relación Estructura-ActividadRESUMEN
The aims of the present investigation were to assess the antibacterial, antifungal, enzyme inhibition and hemolytic activities of various fractions of Rhynchosia pseudo-cajan Cambess. The methanolic extract of the plant was dissolved in the water (distilled) and then partitioned with the n-hexane, chloroform, EtOAc and n-BuOH sequentially. Antibacterial activity was checked against Escherichia coli, Pasturella multocida, Bacillus subtilis and Staphylococcus aureus by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Chloroform and ethyl acetate soluble fractions showed good activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. These fractions also showed good MIC values. The n-butanol soluble and remaining aqueous fraction also showed good activity against some strains. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. Chloroform, n-butanol and ethyl acetate soluble fraction showed good activity only against G. lucidum. Enzyme inhibition studies were done against four enzymes i.e. α-glucosidase, butyrylcholinesterase, acetyl cholinesterase and lipoxygenase. Aqueous fraction possessed very good activity against α-glucosidase, even greater than acarbose, a reference standard drug. Its IC50 value was found as 29.81±0.12 µg/ml as compared to acarbose having IC50 38.62±0.04 µg/ml. Chlroform and ethyl acetate soluble fractions also showed good activity against α-glucosidase. Ethyl acetate soluble and remaining aqueous fractions showed good activity against lipoxygenase. All the studied fractions showed very less toxicity i.e. <2.5%.
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Antibacterianos/farmacología , Antifúngicos/farmacología , Fabaceae/química , Hemólisis/efectos de los fármacos , Hemolíticos/farmacología , Extractos Vegetales/farmacología , 1-Butanol/química , Bacterias/efectos de los fármacos , Cloroformo/química , Pruebas Antimicrobianas de Difusión por Disco/métodos , Hongos/efectos de los fármacos , Hexanos/química , Pruebas de Sensibilidad Microbiana/métodos , Fitoterapia/métodosRESUMEN
The present study comprises the synthesis of a new series of benzenesulfonamides derived from N-sulfonation of 2-(4-methoxyphenyl)-1-ethanamine (1). The synthesis was initiated by the reaction of 2-(4-methoxyphenyl)-1-ethanamine (1) with benzenesulfonyl chloride (2), to yield N-(4-methoxyphenethyl)benzenesulfonamide (3). This parent molecule 3 was subsequently treated with various alkyl/aralkyl halides (4a-j) in N,N-dimethylformamide (DMF) and in the presence of a weak base lithium hydride (LiH) to obtain various N-(alkyl/aralkyl)-N-(4-methoxyphenethyl) benzenesulfonamides (5a-j). The characterization of these derivatives was carried out by spectroscopic techniques like IR, 1H-NMR, and 13C-NMR. Elemental analysis also supported this data. The biofilm inhibitory action of all the synthesized compounds was carried out on Escherichia coli and some of the compounds were identified to be very suitable inhibitors of this bacterial strain. Furthermore, the molecules were also tested for their cytotoxicity behavior to assess their utility as less cytotoxic therapeutic agents.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Sulfonamidas/síntesis química , Sulfonamidas/farmacología , Biopelículas/efectos de los fármacos , Relación Estructura-Actividad , Sulfonamidas/química , BencenosulfonamidasRESUMEN
Neutralization of bacterial cell surface potential using nanoscale materials is an effective strategy to alter membrane permeability, cytoplasmic leakage, and ultimate cell death. In the present study, an attempt was made to prepare biogenic silver nanoparticles using biomolecules from the aqueous rhizome extract of Coptis Chinensis. The biosynthesized silver nanoparticles were surface modified with chitosan biopolymer. The prepared silver nanoparticles and chitosan modified silver nanoparticles were cubic crystalline structures (XRD) with an average particle size of 15 and 20 nm respectively (TEM, DLS). The biosynthesized silver nanoparticles were surface stabilized by polyphenolic compounds (FTIR). Coptis Chinensis mediated silver nanoparticles displayed significant activity against E. coli and Bacillus subtilus with a zone of inhibition 12 ± 1.2 (MIC = 25 µg/mL) and 18 ± 1.6 mm (MIC = 12.50 µg/mL) respectively. The bactericidal efficacy of these nanoparticles was considerably increased upon surface modification with chitosan biopolymer. The chitosan modified biogenic silver nanoparticles exhibited promising activity against E. coli (MIC = 6.25 µg/mL) and Bacillus subtilus (MIC = 12.50 µg/mL). Our results indicated that the chitosan modified silver nanoparticles were promising agents in damaging bacterial membrane potential and induction of high level of intracellular reactive oxygen species (ROS). In addition, these nanoparticles were observed to induce the release of the high level of cytoplasmic materials especially protein and nucleic acids into the media. All these findings suggest that the chitosan functionalized silver nanoparticles are efficient agents in disrupting bacterial membrane and induction of ROS leading to cytoplasmic leakage and cell death. These findings further conclude that the bacterial-nanoparticles surface potential modulation is an effective strategy in enhancing the antibacterial potency of silver nanoparticles.
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Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Tecnología Química Verde , Nanopartículas del Metal/administración & dosificación , Plata , Antibacterianos/química , Bacterias/metabolismo , Bacterias/ultraestructura , Potenciales de la Membrana/efectos de los fármacos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Extractos Vegetales/química , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos XRESUMEN
The aim of the research work was to synthesize different biologically active carbamate derivatives bearing 2-furoyl-1-piperazine and having modest toxicity. The synthesis was completed as a multiple sequence. The structural confirmation of all the synthesized compounds was obtained by EI-MS, IR and 1H-NMR spectral data. The enzyme inhibition and antibacterial potential of the synthesized compounds was evaluated. To find the utility of the prepared compounds as possible therapeutic agents their cytotoxicity was also checked. All the compounds were active against acetylcholinesterase enzyme, especially 12 and 14 showed very good inhibitory potential relative to Eserine, a reference standard. Almost all the compounds showed good activities against both Gram-positive and Gram-negative bacterial strains.