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1.
Nanotechnology ; 35(29)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38593756

RESUMO

Many studies suggest that probabilistic spiking in biological neural systems is beneficial as it aids learning and provides Bayesian inference-like dynamics. If appropriately utilised, noise and stochasticity in nanoscale devices can benefit neuromorphic systems. In this paper, we build a stochastic leaky integrate and fire (LIF) neuron, utilising a Mott memristor's inherent stochastic switching dynamics. We demonstrate that the developed LIF neuron is capable of biological neural dynamics. We leverage these characteristics of the proposed LIF neuron by integrating it into a population-coded spiking neural network and a spiking restricted Boltzmann machine (sRBM), thereby showcasing its ability to implement probabilistic learning and inference. The sRBM achieves a software-comparable accuracy of 87.13%. Unlike CMOS-based probabilistic neurons, our design does not require any external noise sources. The designed neurons are highly energy efficient and ultra-compact, requiring only three components: a resistor, a capacitor and a memristor device.

2.
Bioorg Chem ; 145: 107254, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432152

RESUMO

Vanillic acid (VA) - a naturally occurring phenolic compound in plants - is not only used as a flavoring agent but also a prominent metabolite post tea consumption. VA and its associated compounds are believed to play a significant role in preventing diseases, underscoring the need for a systematic investigation. Herein, we report a 4-step synthesis employing the classical organic reactions, such as Willamson's alkylation, Fischer-Spier reaction, and Steglich esterification, complemented with a protection-deprotection strategy to prepare 46 VA derivatives across the five series (1a-1i, 2a-2i, 3, 3a-3i, 4a-4i, 5a-5i) in high yields. The synthesized compounds were investigated for their antifungal, anti-inflammatory, and toxic effects. Notably, compound 1a demonstrated remarkable ROS inhibition with an IC50 value of 5.1 ± 0.7 µg/mL, which is more than twice as effective as the standard ibuprofen drug. A subset of the synthesized derivatives (2b, 2c, 2e, 3b-3d, 4a-4c, 5a, and 5e) manifested their antifungal effect against drug-resistant Candida strains. Compound 5g, in particular, revealed synergism with the established antifungal drugs amphotericin B (AMB) and fluconazole (FLZ), doubling FLZ's potency against azole resistant Candida albican ATCC 36082. Furthermore, 5g improved the potency of these antifungals against FLZ-sensitive strains, including C. glabrata ATCC 2001 and C. parapsilosis ATCC 22019, as well as various multidrug-resistant (MDR) Candida strains, namely C. albicans ATCC 14053, C. albicans CL1, and C. krusei SH2L OM341600. Additionally, pharmacodynamics of compound 5g was examined using time-kill assay, and a benign safety profile was observed with no hemolytic activity in whole blood, and no cytotoxicity towards the normal BJ human cell line. The synergistic potential of 5g was further investigated through both experimental methods and docking simulations.These findings highlight the therapeutic potential of VA derivatives, particularly in addressing inflammation and circumventing FLZ resistance in Candida albicans.


Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Ácido Vanílico/farmacologia , Ácido Vanílico/uso terapêutico , Azóis/farmacologia , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Fluconazol/farmacologia , Candida , Candida albicans , Candida glabrata , Inflamação/tratamento farmacológico
3.
Phytother Res ; 38(1): 331-348, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37882581

RESUMO

The isothiocyanates (ITCs) derived from the precursor glucosinolate molecules present in Brassica vegetables are bioactive organo-sulfur compounds with numerous pharmacologically important properties such as antioxidant, antiinflammatory, antimicrobial, and anticancer. Over the years, ITCs have been the focus of several research investigations associated with cancer treatment. Due to their potent chemo-preventive action, ITCs have been considered to be promising therapeutics for cancer therapy in place of the already existing conventional anticancer drugs. However, their wide spread use at the clinical stage is greatly restricted due to several factors such as low solubility in an aqueous medium, low bioavailability, low stability, and hormetic effect. To overcome these hindrances, nanotechnology can be exploited to develop nano-scale delivery systems that have the potential to enhance stability, and bioavailability and minimize the hermetic effect of ITCs.


Assuntos
Anticarcinógenos , Antineoplásicos , Brassica , Isotiocianatos/farmacologia , Verduras , Anticarcinógenos/farmacologia , Anticarcinógenos/uso terapêutico , Antineoplásicos/farmacologia
4.
J Mol Recognit ; 36(6): e3010, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36880368

RESUMO

The binding affinity of a drug with carrier proteins plays a major role in the distribution and administration of the drug within the body. Tizanidine (TND) is a muscle relaxant having antispasmodic and antispastic effects. Herein, we have studied the effect of tizanidine on serum albumins by spectroscopic techniques, such as absorption spectroscopic analysis, steady, state fluorescence, synchronous fluorescence, circular dichroism, and molecular docking. The binding constant and number of binding sites of TND with serum proteins were determined by means of fluorescence data. The thermodynamic parameters, like Gibbs' free energy (ΔG), enthalpy change (ΔH), and entropy change (ΔS), revealed that the complex formation is spontaneous, exothermic, and entropy driven. Further, synchronous spectroscopy revealed the involvement of Trp (amino acid) responsible for quenching of intensity in fluorescence in serum albumins in presence of TND. Circular dichroism results suggest that more folded secondary structure of proteins. In BSA the presence of 20 µM concentration of TND was able to gain most of its helical content. Similarly, in HSA the presence of 40 µM concentration of TND has been able to gain more helical content. Molecular docking and molecular dynamic simulation further confirm the binding of TND with serum albumins, thus validating our experimental results.


Assuntos
Músculos , Albumina Sérica , Simulação de Acoplamento Molecular , Preparações Farmacêuticas/metabolismo , Sítios de Ligação , Dicroísmo Circular , Termodinâmica , Músculos/metabolismo , Espectrometria de Fluorescência , Ligação Proteica , Soroalbumina Bovina/química
5.
Molecules ; 29(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38202737

RESUMO

Tinospora bakis (A.Rich.) Miers (Menispermaceae) has traditionally been used to alleviate headaches, rheumatism, mycetoma, and diabetes, among others. Despite its extensive use, the active components of the plant have never been investigated. In this work, a series of furanoditerpenoids (1-18) and five compounds from other classes (19-23) were isolated from T. bakis. Notably, two new compounds were discovered and named: tinobakisin (1) and tinobakiside (10). Their molecular structures were elucidated with NMR, MS, UV, IR, and ECD spectra. Additionally, known compounds (2-9 and 11-23) were corroboratively identified through spectral comparisons with previously reported data, while highlighting and addressing some inaccuracies in the prior literature. Remarkably, compounds 6, 7, 13, and 17 exhibited a superior anti-glycation effect, outperforming established agents like rutin and quercetin in a lab model of protein glycation with glucose. The overall findings suggest that furanoditerpenoids play a crucial role in the antidiabetic properties of T. bakis. This research marks the first comprehensive phytochemical investigation of T. bakis, opening the door for further investigation into furanoditerpenoids and their biological mechanisms.


Assuntos
Besouros , Diterpenos Clerodânicos , Menispermaceae , Tinospora , Animais , Diterpenos Clerodânicos/farmacologia , Glucose
6.
J Sci Food Agric ; 103(1): 73-82, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35794734

RESUMO

BACKGROUND: Ginger oleoresin is prone to destruction from air, light and high temperatures and has a limited shelf life if kept improperly. Its viscous and sticky characteristics also make it difficult to handle and utilize. These issues can be solved via microencapsulation. The goal of this research was to evaluate how different wall materials affect the properties of microencapsulated ginger oleoresin powder. RESULTS: Ginger oleoresin microcapsules were developed through spray drying technique using gum acacia (GA) and whey protein isolate (WPI) as wall materials. The characteristics of the obtained powder, including water activity, wettability and encapsulation efficiency, were evaluated, corresponded to values of 0.20, 90.54 s and 84.15% for whey protein isolate-based ginger oleoresin powder. Whey protein isolate microcapsules also exhibited higher phenolic content (27.26 mg gallic acid equivalents g-1 ), total flavonoid (2.94 mg quercetin equivalents g-1 ) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (68.71%) than GA microcapsules. Both WPI- and GA-based oleoresin microcapsules displayed poor flowability, but possessed a metastable amorphous state as indicated by X-ray diffraction. GA-encapsulated oleoresin microcapsules showed a significant increase in particle size (1983 nm) compared to WPI oleoresin microcapsules. Fourier transform infrared analysis of the developed oleoresin microcapsules indicated no change in molecular structure except for a variation in peak intensity. CONCLUSION: Whey protein isolate proved to be more efficient in maintaining the physicochemical and antioxidant activity of spray-dried ginger oleoresin powder. The present study revealed whey protein-based oleoresin powder could be used as a therapeutic agent in various nutraceutical applications. © 2022 Society of Chemical Industry.


Assuntos
Antioxidantes , Zingiber officinale , Cápsulas/química , Antioxidantes/química , Proteínas do Soro do Leite , Excipientes , Pós/química , Goma Arábica/química
7.
Medicina (Kaunas) ; 59(4)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37109636

RESUMO

Background and objectives: Endodontic surgery has evolved over the last two decades. The use of state-of-the-art guided endodontic surgical procedures produces a predictable outcome in the healing of lesions of endodontic origin. The main objective of this review paper is to define and characterize guided surgical endodontics as well as its benefits and drawbacks by reviewing the most recent relevant scientific literature. Methods: A literature search was conducted using multiple databases comprising of MEDLINE (via PubMed), EMBASE, and Web of Science. The terms used for the search were 'guided endodontics', 'surgical endodontics', and 'endodontic microsurgery'. Results: In total, 1152 articles were obtained from the analysis of the databases. Unrelated articles from the available full text of 388 articles were excluded. A total of 45 studies were finally included in the review. Conclusions: Surgical-guided endodontics is a relatively new area of study that is still maturing. It has many applications such as root canal access and localization, microsurgical endodontics, endodontic retreatment, and glass fiber post removal. Additionally, it does not matter how experienced the operator is; the procedure can be completed for the patient in less time and provides greater accuracy and safety than conventional endodontics.


Assuntos
Endodontia , Tratamento do Canal Radicular , Humanos , Tratamento do Canal Radicular/métodos , Endodontia/métodos , Microcirurgia/métodos
8.
Physiol Mol Biol Plants ; 29(12): 2005-2020, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38222272

RESUMO

Anthracnose (ANT) caused by Colletotrichum lindemuthianum is the most devastating seed-borne fungal disease of common bean. In response to fungal infections, it is hypothesized that pathogen-plant interactions typically cause hypersensitive reactions by producing reactive oxygen species, hydrogen peroxide and lipid peroxidation of cell membranes. esent study was conducted by inoculating susceptible bean genotype "SB174" and resistant bean genotype "E10" with pathogen "C. lindemuthianum". Defense-related enzymes (ascorbate peroxidase, peroxidase, lipid peroxidase, and catalase) and C-based compounds (total phenols and flavonoids) were studied using the detached bean leaf method. Comparative defense response was studied in different plant tissues (pod, stem, and seed) in susceptible and resistant bean genotypes under uninoculated and pathogen-inoculated conditions. The host‒pathogen interaction was studied at mock inoculation, 2, 4 and 6 days after inoculation (dai). Comparing the pathogen-inoculated bean leaves to water-treated bean leaves, defense enzymes as well as total phenols and flavonoids exhibited differential expression. In a comparative study, the enzyme activity also displayed differential biochemical responses in pods, stems and seeds in both contrasting genotypes. For example, 5.1-fold (pod), 1.5-fold (stem) and 1.06-fold (seed) increases in ascorbate peroxidase activity were observed in the susceptible genotype at 6 dai compared to mock inoculation. Similarly, catalase activity in pods was upregulated (1.47-fold) in the resistant genotype and downregulated (1.30-fold) in the susceptible genotype at 6 dai. The study revealed that defense-related antioxidative enzymes, phenols and flavonoids are fine-tuned to detoxify important reactive oxygen species (ROS) molecules, induce systemic resistance and are successfully controlled in common bean plants against pathogen invasion.

9.
J Clin Pediatr Dent ; 47(4): 80-85, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37408350

RESUMO

Orthodontic treatment requires the cooperation of patients as well as orthodontists. Therefore, the aim of the study was to investigate and address the challenges and barriers orthodontists have in achieving the desired orthodontic results, as well as make recommendations for ways to address the stated problems and introduce new innovative technologies to the area of orthodontics. This qualitative study wasbased on the grounded theory. Twelve orthodontists participated in face-to-face interviews, which were primarily comprised of open-ended questions. Data analysis was carried out manually using the "by hand" method. Orthodontists between the age group of 29-42 were interviewed. The answers varied depending on the years of experience of the interviewees. Teenagers and boys were found to be most non-compliant with the treatment. The average treatment span ranged between 6 months for mild cases up to 3 years for severe orthodontic cases occurring most commonly in government hospitals. Patient compliance plays a major role in orthodontics. Poor oral hygiene maintenance, brackets breakage by patients, and missed appointments were the major concerns mentioned by participants and hindered getting the desired results. Patients' main worries were related to the cost of therapy, premolar extractions, the length of treatment, and the possibility of relapse. Patient counseling and reinforcement at the start of the treatment can help to overcome the challenges and barriers in orthodontics since patient motivation is a very important factor in obtaining the desired results. It is recommended to conduct more training sessions for the orthodontists in order to introduce them to new technological paradigms.


Assuntos
Ortodontia , Masculino , Humanos , Adulto , Criança , Adolescente , Ortodontistas , Assistência Odontológica , Inquéritos e Questionários
10.
Am J Physiol Gastrointest Liver Physiol ; 322(6): G561-G570, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35293263

RESUMO

Proper mitochondrial function and adequate cellular ATP are necessary for normal pancreatic protein synthesis and sorting, maintenance of intracellular organelles and enzyme secretion. Inorganic phosphate is required for generating ATP and its limited availability may lead to reduced ATP production causing impaired Ca2+ handling, defective autophagy, zymogen activation, and necrosis, which are all features of acute pancreatitis. We hypothesized that reduced dietary phosphate leads to hypophosphatemia and exacerbates pancreatitis severity of multiple causes. We observed that mice fed a low-phosphate diet before the induction of pancreatitis by either repeated caerulein administration or pancreatic duct injection as a model of pressure-induced pancreatitis developed hypophosphatemia and exhibited more severe pancreatitis than normophosphatemic mice. Pancreatitis severity was significantly reduced in mice treated with phosphate. In vitro modeling of secretagogue- and pressure-induced pancreatic injury was evaluated in isolated pancreatic acini using cholecystokinin and the mechanoreceptor Piezo1 agonist, Yoda1, under low and normal phosphate conditions. Isolated pancreatic acini were more sensitive to cholecystokinin- and Yoda1-induced acinar cell damage and mitochondrial dysfunction under low-phosphate conditions and improved following phosphate supplementation. Importantly, even mice on a normal phosphate diet exhibited less severe pancreatitis when treated with supplemental phosphate. Thus, hypophosphatemia sensitizes animals to pancreatitis and phosphate supplementation reduces pancreatitis severity. These appear to be direct effects of phosphate on acinar cells through restoration of mitochondrial function. We propose that phosphate administration may be useful in the treatment of acute pancreatitis.NEW & NOTEWORTHY Impaired ATP synthesis disrupts acinar cell homeostasis and is an early step in pancreatitis. We report that reduced phosphate availability impairs mitochondrial function and worsens pancreatic injury. Phosphate supplementation improves mitochondrial function and protects against experimental pancreatitis, raising the possibility that phosphate supplementation may be useful in treating pancreatitis.


Assuntos
Hipofosfatemia , Pancreatite , Doença Aguda , Trifosfato de Adenosina/metabolismo , Animais , Ceruletídeo/farmacologia , Colecistocinina/metabolismo , Hipofosfatemia/metabolismo , Canais Iônicos/metabolismo , Camundongos , Pâncreas/metabolismo , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Fosfatos/metabolismo
11.
Gastroenterology ; 161(3): 982-995.e2, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34051238

RESUMO

BACKGROUND & AIMS: Heavy alcohol consumption is a common cause of acute pancreatitis; however, alcohol abuse does not always result in clinical pancreatitis. As a consequence, the factors responsible for alcohol-induced pancreatitis are not well understood. In experimental animals, it has been difficult to produce pancreatitis with alcohol. Clinically, alcohol use predisposes to hypophosphatemia, and hypophosphatemia has been observed in some patients with acute pancreatitis. Because of abundant protein synthesis, the pancreas has high metabolic demands, and reduced mitochondrial function leads to organelle dysfunction and pancreatitis. We proposed, therefore, that phosphate deficiency might limit adenosine triphosphate synthesis and thereby contribute to alcohol-induced pancreatitis. METHODS: Mice were fed a low-phosphate diet (LPD) before orogastric administration of ethanol. Direct effects of phosphate and ethanol were evaluated in vitro in isolated mouse pancreatic acini. RESULTS: LPD reduced serum phosphate levels. Intragastric administration of ethanol to animals maintained on an LPD caused severe pancreatitis that was ameliorated by phosphate repletion. In pancreatic acinar cells, low-phosphate conditions increased susceptibility to ethanol-induced cellular dysfunction through decreased bioenergetic stores, specifically affecting total cellular adenosine triphosphate and mitochondrial function. Phosphate supplementation prevented ethanol-associated cellular injury. CONCLUSIONS: Phosphate status plays a critical role in predisposition to and protection from alcohol-induced acinar cell dysfunction and the development of acute alcohol-induced pancreatitis. This finding may explain why pancreatitis develops in only some individuals with heavy alcohol use and suggests a potential novel therapeutic approach to pancreatitis. Finally, an LPD plus ethanol provides a new model for studying alcohol-associated pancreatic injury.


Assuntos
Metabolismo Energético , Hipofosfatemia/complicações , Mitocôndrias/metabolismo , Pâncreas/metabolismo , Pancreatite Alcoólica/metabolismo , Fosfatos/deficiência , Trifosfato de Adenosina/metabolismo , Animais , Modelos Animais de Doenças , Etanol , Hipofosfatemia/metabolismo , Hipofosfatemia/prevenção & controle , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Pâncreas/patologia , Pancreatite Alcoólica/induzido quimicamente , Pancreatite Alcoólica/patologia , Pancreatite Alcoólica/prevenção & controle , Fosfatos/administração & dosagem , Índice de Gravidade de Doença , Técnicas de Cultura de Tecidos
12.
Bioorg Chem ; 129: 106187, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36215785

RESUMO

A synthetic anabolic-androgenic steroid, methylstenbolone (1), was structurally transformed into a series of nine analogues, 2,17α-dimethyl-7α,17ß-dihydroxy-5α-androst-1-en-3-one (2), 2,17α-dimethyl-15ß,17ß-dihydroxy-5α-androst-1-en-3-one (3), 2,17α-dimethyl-6α,9α,17ß-trihydroxy-5α-androst-1-en-3-one (4), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3-one (5), 2-methyl-11ß,17ß-dihydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3-one (6), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3,6-dione (7), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5ß-androst-1-en-3,6-dione (8), 2,17α-dimethyl-7ß,17ß-dihydroxy-5α-androst-1-en-3-one (9), and 2,17α-dimethyl-12ß,17ß-hydroxy-5α-androst-1-en-3,7-dione (10) by fungal cell suspension cultures, Macrophomina phaseolina and Cunninghamella blakesleeana for the first time. Among those, compounds 2-4 and 6-10 were identified as new. Herein, spectral data of metabolite 5 was reported for the first time. Their structures were elucidated by NMR, MS, UV, and IR spectroscopic methods. Substrate 1 (IC50 10.1 ± 0.3 µg/mL) was identified as a potent anti-inflammatory agent against nitric oxide (NO) production. Its transformed products 3 (IC50 as 27.8 ± 1.1 µg/mL) and 9 (26.9 ± 0.4 µg/mL) displayed good inhibition. Compounds 2 (IC50 = 45.9 ± 0.8 µg/mL) and 6 (IC50 = 36.6 ± 1.2 µg/mL) were also active moderately against NO production, in comparison to standard LNMMA (IC50 = 24.2 ± 0.8 µg/mL). Cytotoxicity assay showed 1 was active to cancer cell line MCF7 (IC50 = 12.26 ± 0.35 µg/mL), compared to the standard Doxorubicin having IC50 as 1.25 ± 0.11 µg/mL. However, it is also toxic to human normal cell line (BJ) with IC50 as 8.69 ± 0.02 µg/mL. More importantly, all transformed products are non-cytotoxic on BJ. Therefore, biotransformation can be an efficient approach to reduce the toxicity of methylstenbolone.


Assuntos
Androstenóis , Anti-Inflamatórios , Humanos , Biotransformação , Anti-Inflamatórios/farmacologia
13.
Sensors (Basel) ; 22(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35408283

RESUMO

Reliable and efficient reconstruction of pure quantum states under the processing of noisy measurement data is a vital tool in fundamental and applied quantum information sciences owing to communication, sensing, and computing. Specifically, the purity of such reconstructed quantum systems is crucial in surpassing the classical shot-noise limit and achieving the Heisenberg limit, regarding the achievable precision in quantum sensing. However, the noisy reconstruction of such resourceful sensing probes limits the quantum advantage in precise quantum sensing. For this, we formulate a pure quantum state reconstruction method through eigenvalue decomposition. We show that the proposed method is robust against the depolarizing noise; it remains unaffected under high strength white noise and achieves quantum state reconstruction accuracy similar to the noiseless case.

14.
Sensors (Basel) ; 22(7)2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35408383

RESUMO

This paper presents a design of multiple input multiple output (MIMO) antenna array for 5G millimeter-wave (mm-wave) communication systems. The proposed MIMO configuration consists of a two antenna arrays combination. Each antenna array consists of four elements which are arranged in an even manner, while two arrays are then assembled with a 90-degree shift with respect to each other. The substrate used is a 0.254 mm thick Rogers RT5880 with a dielectric constant of 2.2 and loss tangent of 0.0009, correspondingly. The proposed MIMO antenna array covers the 37 GHz frequency band, dedicated for 5G millimeter-wave communication applications. The proposed antenna element yields a gain of 6.84 dB, which is enhanced up to 12.8 dB by adopting a four elements array configuration. The proposed MIMO antenna array performance metrics, such as envelope correlation coefficient (ECC) and diversity gain (DG), are observed, which are found to be under the standard threshold. More than 85% of the radiation efficiency of the proposed MIMO antenna array is observed to be within the desired operating frequency band. All the proposed designs are simulated in computer simulation technology (CST) software. Furthermore, the measurements are carried out for the proposed MIMO antenna array, where a good agreement with simulated results is observed. Thus, the proposed design can be a potential candidate for 5G millimeter-wave communication systems.


Assuntos
Software , Tecnologia sem Fio , Comunicação , Simulação por Computador , Desenho de Equipamento
15.
Molecules ; 27(4)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35209101

RESUMO

Two new ursane-type triterpenoids, named Polyanside A (1) and B (2), along with eleven known compounds (3-13), were isolated and elucidated from Maranthes polyandra (Benth.) Prance. The structures of these compounds were elucidated based on chemical evidence and multiple spectroscopic data. Isolated compounds were evaluated for anti-cancer, anti-inflammatory activities, and cytotoxicity on a normal human cell line (BJ). None of them showed activity and cytotoxicity. The hexane fraction was analyzed by GC-MS, resulting in the identification of forty-one compounds. This is the first comprehensive study on the phytochemistry of M. polyandra.


Assuntos
Chrysobalanaceae/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Fracionamento Químico , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
16.
Molecules ; 28(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36615406

RESUMO

The emergence of multidrug-resistant (MDR) pathogens and the gradual depletion of available antibiotics have exacerbated the need for novel antimicrobial agents with minimal toxicity. Herein, we report functionally substituted pyridine carbohydrazide with remarkable antimicrobial effect on multi-drug resistant strains. In the series, compound 6 had potent activity against four MDR strains of Candida spp., with minimum inhibitory concentration (MIC) values being in the range of 16-24 µg/mL and percentage inhibition up to 92.57%, which was exceptional when compared to broad-spectrum antifungal drug fluconazole (MIC = 20 µg/mL, 81.88% inhibition). Substitution of the octyl chain in 6 with a shorter butyl chain resulted in a significant anti-bacterial effect of 4 against Pseudomonas aeruginosa (ATCC 27853), the MIC value being 2-fold superior to the standard combination of ampicillin/cloxacillin. Time-kill kinetics assays were used to discern the efficacy and pharmacodynamics of the potent compounds. Further, hemolysis tests confirmed that both compounds had better safety profiles than the standard drugs. Besides, molecular docking simulations were used to further explore their mode of interaction with target proteins. Overall results suggest that these compounds have the potential to become promising antimicrobial drugs against MDR strains.


Assuntos
Anti-Infecciosos , Antifúngicos , Antifúngicos/farmacologia , Simulação de Acoplamento Molecular , Farmacorresistência Bacteriana Múltipla , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Piridinas/farmacologia , Testes de Sensibilidade Microbiana
17.
Environ Monit Assess ; 194(6): 393, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35482106

RESUMO

The present study was carried out to monitor the ambient concentrations of particulate matter and carbon dioxide caused by vehicular pollution in Srinagar City of Jammu and Kashmir, India, for a period of 12 months from June 2019 to May 2020 as the major contributions in these areas are due to vehicular movement. Out of five, four locations (viz. Dalgate, Jehangir Chowk, Parimpora and Pantha Chowk) had highest traffic density in the city and the fifth location (Shalimar) had low traffic volume. The sampling was done on every fortnight using AEROCET 831-aerosol mass monitor and CDM 901-CO2 monitor with each sampling being carried out three times a day, i.e. morning (9:00 am-10:30 am), afternoon (1:00 pm-2:30 pm) and evening (4:30 pm-6:00 pm) with three replications at each site based on the peak traffic hours. The results show that during the whole period, average PM1 concentrations ranged from 15.10 to 108.9 µg/m3, PM2.5 (28.70-577.50 µg/m3), PM4 (44.50-780.87 µg/m3), PM10 (57.13-1225.53 µg/m3), total suspended particulates (77.77-1410.27 µg/m3) and CO2 (332.4-655.0 ppm). The average concentrations of these parameters showed that the maximum PM1 concentration was found at Dalgate (53.77 µg/m3) and PM2.5 had its maximum average concentration at Jehangir Chowk (140.13 µg/m3). Other parameters like PM4, PM10, TSP and CO2 had a maximum average values at Jehangir Chowk (240.23 µg/m3, 633.40 µg/m3, 853.50 µg/m3 and 533.20 ppm, respectively). The pollution load was observed to be maximum during winter season followed by autumn, summer and spring. The lowest concentration of all pollutants except CO2 was observed in April 2020 and this might be due to COVID-19 lockdown observed in the country during the same period.


Assuntos
Poluentes Atmosféricos , COVID-19 , Poluentes Atmosféricos/análise , Dióxido de Carbono , Controle de Doenças Transmissíveis , Monitoramento Ambiental/métodos , Humanos , Material Particulado/análise
18.
Bull Environ Contam Toxicol ; 108(6): 1088-1097, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35113217

RESUMO

The present study was carried out during the years 2017-2018 and assessed the impact of anthropogenic activities on the physico-chemical characteristics of soil in the Kashmir Himalaya. At disturbed sites anthropogenic activities like deforestation, grazing, tourism, urbanization, traffic etc. are seen prominent and their effect on soil environment resulted in less vegetation cover and exhibited diminution in organic matter. There was a significant increase in moisture content (21.13 ± 1.51), organic carbon (2.65% ± 0.52%), available nitrogen (493.790 ± 2.105 kg/ha), and potassium (432.727 ± 1.738 kg/ha) at undisturbed area Baerabal Harwan. However, there was a reduced pH (5.39 ± 0.230) and available phosphorus (18.993 ± 1.370) at undisturbed area in contrast to disturbed sites. Significantly higher values of Fe, Cu, Zn and Ni were found in disturbed areas (46.33 ± 0.16, 3.972 ± 0.001, 2.224 ± 0.003 and 1.7033 ± 0.002 ppm) respectively. The present findings could be helpful in formulating conservation strategies of soil at disturbed areas that are affected by anthropogenic activities which effects the soil microbial health of the forest soils. The study therefore indicated the need for employing best forest management and effective enforcement with vigorous reforestation programmes and would be a way forward towards mitigating the ongoing deterioration of the plant-soil system, sustaining forest productivity and soil fertility in the long run, and protecting people's livelihoods.


Assuntos
Poluentes do Solo , Solo , Efeitos Antropogênicos , Carbono , Florestas , Humanos , Solo/química , Poluentes do Solo/análise
19.
Phytother Res ; 35(2): 823-834, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32930436

RESUMO

Aberrations in epigenetic mechanisms provide a fertile platform for tumour initiation and progression. Thus, agents capable of modulating the epigenetic environment of neoplasms will be a valuable addition to the anticancer therapeutics. Flavones are emerging as befitting anticancer agents due to their inherent antioxidant activity and the ability to restrain epi-targets namely histone deacetylases (HDACs). HDACs have broader implications in pathogenesis of various cancers. Chrysin, a flavone possessing the ability to inhibit HDACs could prove as a potential anticancer drug. Thus, in this article we focussed on Chrysin and its distinct antineoplastic effect against bellicose malignancies including lung, colorectal, cervical, gastric, melanoma, hepatocellular carcinoma and breast cancer. The underlying signalling cascades triggered by Chrysin for inducing cytotoxic effect in these cancer models are discussed. Importantly, approaches towards combinatorial treatments by Chrysin and commercial anticancer agents are taken into account. The downstream molecular mechanism aroused by combined therapy for abrogating onerous cancer chemoresistance is delineated as well. Moreover, the nano-combinatorial approach involving co-encapsulation of Chrysin with other herbal and non-herbal agents for clinical excellence is elucidated.


Assuntos
Antineoplásicos/uso terapêutico , Epigênese Genética/efeitos dos fármacos , Flavonas/química , Flavonoides/química , Inibidores de Histona Desacetilases/uso terapêutico , Plantas/química , Antineoplásicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Humanos
20.
Phytother Res ; 35(7): 3509-3532, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33580629

RESUMO

Various signaling mechanisms contribute significantly to the development of multiple cancers. Small molecules with the potential of influencing a wide variety of molecular targets may prove as broad-spectrum anticancer agents. Flavonoids from plant sources are strongly emerging as promising antineoplastic molecules because of their ability to hamper different cancer-driving signaling pathways. Further, these flavonoids offer an additional benefit due to their congenital antioxidant potential. This paper discusses the anticancer activity of luteolin against a number of cancers including leukemias, prostate cancer, pancreatic cancer, breast cancer, lung cancer, colorectal cancer, melanoma, liver, gastric, and brain cancer. Strong emphasis has been laid on key molecular mechanisms impacted by luteolin for exerting antineoplastic effect. Importantly, certain epigenetic targets like histone deacetylases (HDACs), DNA methylation regulator enzymes that are influenced by this befitting flavone for inducing cytotoxicity in certain preclinical cancer models, have also been made the part of this review. Additionally, the significantly improved therapeutic benefits of luteolin in combination with other therapeutics are comprehensively discussed. The current loopholes in luteolin research are also considered, which may open novel routes for further valuable studies on this promising flavone.


Assuntos
Antineoplásicos Fitogênicos , Luteolina , Neoplasias , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Humanos , Luteolina/farmacologia , Luteolina/uso terapêutico , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
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