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1.
Langmuir ; 38(35): 10893-10901, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36007164

RESUMEN

The organization of the self-assembled monolayer (SAM) determines its electronic structure and so governs the charge transport process and device performance when adopted into a molecular device. We report a systematic study on the supramolecular structure and rectification performance of the ferrocene (11-ferrocenyl-1-undecanethiol, FUT) based SAM modulated by mixed SAM with inert 1-undecanethiol (C11SH) as diluent. We compared mixed SAMs by two different post assembly strategies, i.e., post assembly of C11SH on FUT SAM and post assembly of FUT on C11SH SAM. The organization and structure of FUT in the mixed SAM were extensively studied by cyclic voltammetry (CV) using the Laviron model. Rectification properties of the mixed SAM obtained using eutectic indium gallium (EGaIn) as the top electrode revealed that the magnitude and stability of the rectification ratio (RR) strongly correlated to not only the amount but also the phase structure and orientation of the FUT in the monolayer, resulting in a tunable RR and increased stability. The mixed monolayer achieved an increased performance relative to pure FUT by post assembling FUT on C11SH SAM, which formed an optimally dense and well-packed monolayer with the FUT head resting on the top of the alkane SAM.

2.
J Am Chem Soc ; 142(21): 9708-9717, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32362123

RESUMEN

We report a novel solid-state molecular device structure based on double self-assembled monolayers (D-SAM) incorporated into the suspended nanowire architecture to form a "Au|SAM-1||SAM-2|Au" junction. Using commercially available thiol molecules that are devoid of synthetic difficulty, we constructed a "Au|S-(CH2)6-ferrocene||SAM-2|Au" junction with various lengths and chemical structures of SAM-2 to tune the coupling between the ferrocene conductive molecular orbital and electrode of the junction. Combining low noise and a wide temperature range measurement, we demonstrated systematically modulated conduction depending on the length and chemical nature of SAM-2. Meanwhile, the transport mechanism transition from tunneling to hopping and the intermediate state accompanied by the current fluctuation due to the coexistence of the hopping and tunneling transport channels were observed. Considering the versatility of this solid-state D-SAM in modulating the electrode-molecule interface and electroactive groups, this strategy thus provides a novel facile strategy for tailorable nanoscale charge transport studies and functional molecular devices.

3.
Pak J Pharm Sci ; 33(1): 149-160, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32122843

RESUMEN

A series of new compounds (5a-q), derived from 5-(1-(4-nitrophenylsulfonyl) piperidin-4-yl)-4-phenyl-4H-1,2,4-triazole-3-thiol (3) were proficiently synthesized to evaluate their biological activities. 1-(4-Nitrophenylsulfonyl) piperidine-4-carbohydrazide (2) was refluxed with phenylisothiocyanate to yield an adduct which was cyclized to compound 3 by reflux reaction with 10 % potassium hydroxide. The targeted compounds 5a-q, were synthesized by stirring alkyl/aralkyl halides (4a-q) and compound 3 in a polar aprotic solvent. 1H-NMR, 13C-NMR, EI-MS and IR spectral techniques were employed to confirm the structures of all the synthesized compounds. The compounds were biologically evaluated for BSA binding studies followed by anti-bacterial, anti-inflammatory and acetylcholinesterase (AChE) activities. The active sites responsible for the best AChE inhibition were identified through molecular docking studies. Compound 5e bearing 4-chlorobenzyl moiety found most active antibacterial and anti-inflammatory agent among the synthesized compounds. The whole library of synthesized compounds except compounds 5d and 5f was found highly active for AChE inhibition and recommended for in vivo studies so that their therapeutic applications may come in utilization.


Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Inhibidores de la Colinesterasa/farmacología , Simulación del Acoplamiento Molecular , Albúmina Sérica/metabolismo , Triazoles/farmacología , Antibacterianos/síntesis química , Antiinflamatorios/síntesis química , Inhibidores de la Colinesterasa/síntesis química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Piperidinas/química , Relación Estructura-Actividad , Triazoles/síntesis química , Triazoles/química
5.
Phys Chem Chem Phys ; 21(47): 26058-26065, 2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31746863

RESUMEN

Histidine works as an important mediator in the charge transport process through proteins via its conjugate side group. It can also stabilize a peptide's secondary structure through hydrogen bonding of the imidazole group. In this study, the conformation of the self-assembled monolayer (SAM) and the charge transport of the tailor-made oligopeptide hepta-histidine derivative (7-His) were modulated through the pH control of the assembly environment. Histidine is found to be an efficient tunneling mediator in monolayer junctions with an attenuation factor of ß = ∼0.5 Å-1. Successful theoretical model fitting indicates a linear increase in the number of tunneling sites as the 7-His SAM thickness increases, following the deprotonation of histidine. Combined with the ultraviolet photoelectron spectroscopy (UPS) measurements, a modulable charge transport pathway through 7-His with imidazole groups of histidine as tunneling foot stones is revealed. Histidine therefore possesses a large potential for modulable functional (bio)electronic devices.

6.
Pak J Pharm Sci ; 31(6 (Supplementary): 2645-2654, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30587474

RESUMEN

Microwave and conventional techniques were employed to synthesize a novel array of compounds 7a-g with 1,2,4-triazole and piperidine rings having great biological importance. The microwave assisted method has a better operational scope with respect to time and yield comparative to the conventional method. 1H-NMR, 13C-NMR and IR techniques were employed to justify the structure of synthesized compounds. The antioxidant, butyrylcholinesterase inhibition and urease inhibition potential of every synthesized compound was evaluated. Every member of the synthesized series was found potent against mentioned activities. Compound 7g was the most active anti-urease agent having IC50 (µM) value 16.5±0.09 even better than the thiourea with an IC50(µM) value of 24.3±0.24. The better urease inhibition potential of 7g was also elaborated and explained by docking and bovine serum albumin (BSA) binding studies.


Asunto(s)
Simulación por Computador , Microondas , Simulación del Acoplamiento Molecular/métodos , Albúmina Sérica Bovina/metabolismo , Triazoles/metabolismo , Animales , Bovinos , Unión Proteica/fisiología , Estructura Terciaria de Proteína , Albúmina Sérica Bovina/síntesis química , Relación Estructura-Actividad , Triazoles/síntesis química
7.
Pak J Pharm Sci ; 31(6 (Supplementary): 2697-2708, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30587482

RESUMEN

The research was aimed to unravel the enzymatic potential of sequentially transformed new triazoles by chemically converting 4-methoxybenzoic acid via Fischer's esterification to 4-methoxybenzoate which underwent hydrazinolysis and the corresponding hydrazide (1) was cyclized with phenyl isothiocyanate (2) via 2-(4-methoxybenzoyl)-N-phenylhydrazinecarbothioamide (3); an intermediate to 5-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-triazol-3-thiol (4). The electrophiles; alkyl halides 5(a-g) were further reacted with nucleophilic S-atom to attain a series of S-alkylated 5-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-triazole-3-thiols 6(a-g). Characterization of synthesized compounds was accomplished by contemporary spectral techniques such as FT-IR, 1H-NMR, 13C-NMR and EI-MS. Excellent cholinesterase inhibitory potential was portrayed by 3-(n-heptylthio)-5-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-triazole; 6g against AChE (IC50; 38.35±0.62µM) and BChE (IC50; 147.75±0.67µM) enzymes. Eserine (IC50; 0.04±0.01µM) was used as reference standard. Anti-proliferative activity results ascertained that derivative encompassing long straight chain substituted at S-atom of the moiety was the most potent with 4.96 % cell viability (6g) at 25µM and with 2.41% cell viability at 50µMamong library of synthesized derivatives. In silico analysis also substantiated the bioactivity statistics.


Asunto(s)
Inhibidores de la Colinesterasa/síntesis química , Simulación por Computador , Simulación del Acoplamiento Molecular/métodos , Compuestos de Sulfhidrilo/síntesis química , Triazoles/síntesis química , Inhibidores de la Colinesterasa/metabolismo , Células HCT116 , Humanos , Compuestos de Sulfhidrilo/metabolismo , Triazoles/metabolismo
8.
Pak J Pharm Sci ; 27(3): 517-24, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24811811

RESUMEN

A new series of N-aryl/aralkyl substitued-2"-[(phenylsulfonyl)(piperidin-1-yl)amino]acetamide (7a-k) was synthesized. These derivatives were geared up by the pairing of benzenesulfonyl chloride (4) with 1-aminopiperidine (5) under dynamic pH control in aqueous media to afford parent compound N-(Piperidin-1-yl) benzenesulfonamide (6), followed by the substitution at nitrogen atom with different electrophiles N-aryl/aralkyl-substituted-2-bromoacetamides (3a-k) in the presence of sodium hydride (NaH) and N,N-Dimethylformamide (DMF) to give a new series of N-substituted derivatives of acetamide (7a-k) bearing piperidine moiety. All the synthesized compounds were confirmed on the basis of IR, EIMS and (1)H-NMR spectral data. The synthesized compounds were evaluated against acetylcholinesterase and butyrylcholinesterase (AChE and BChE) respectively and lipoxygenase (LOX) enzymes. Almost all the synthesized compounds displayed promising activity but few of them remained inactive against lipoxygenase enzymes.


Asunto(s)
Acetamidas/síntesis química , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Lipooxigenasa/síntesis química , Acetamidas/farmacología , Acetilcolinesterasa/metabolismo , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Lipooxigenasa/farmacología , Relación Estructura-Actividad
9.
Heliyon ; 10(7): e27303, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38571584

RESUMEN

Five 2-phenylacetohydrazide derivatives (BPAH = N'-benzylidene-2-phenylacetohydrazide, HBPAH = N'-(2-hydroxybenzylidene)-2-phenylacetohydrazide), PPAH = 2-phenyl-N'-3-phenylallylideneacetohydrazide, FMPAH = N'-(furan-2-ylmethylene)-2-phenylaceto hydrazide and EPAH = N'-ethylidene-2-phenylacetohydrazide were synthesized by the condensation of 2-phenylacetohydrazide with the corresponding aldehyde. The synthesized compounds were characterized by FTIR, 1D, and 2D NMR spectroscopy. The structure of the BPAH and PPAH were analyzed by single crystal X-ray diffraction analysis and in both crystallized compounds, the molecules adopted trans geometry around the -C[bond, double bond]N- (imine) functional group. To explore the pharmacological significance of these compounds, the binding ability of these compounds with Bovine Serum Albumin (BSA) was investigated using fluorescence spectroscopy. BPAH and PPAH showed the highest binding ability while EPAH, HBPAH, and FMPAH had lower binding ability to BSA molecules. Thermodynamic parameters ΔG, ΔH°, and ΔS° demonstrated that interactions of BSA with compounds BPAH, EPAH, FMAH, and HBPAH were exothermic while for PPAH it was endothermic. The negative enthalpy and entropy of the compounds BPAH, EPAH, FMAH, and HBPAH indicated that van der Waals' forces and hydrogen bonding played a major role in stabilizing the BSA binding with the molecules. Hydrophobic interactions were predominant in the binding of PPAH with BSA tends to interact with two sets of BSA binding sites with an increase in temperature.

10.
ACS Omega ; 9(14): 16262-16278, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38617664

RESUMEN

Phosphodiesterases (PDEs) are vital in signal transduction, specifically by hydrolyzing cAMP and cGMP. Within the PDE family, PDE10A is notable for its prominence in the striatum and its regulatory function over neurotransmitters in medium-spiny neurons. Given the dopamine deficiency in Parkinson's disease (PD) that affects striatal pathways, PDE10A inhibitors could offer therapeutic benefits by modulating D1 and D2 receptor signaling. This study was motivated by the successful history of quinazoline/quinazoline scaffolds in the inhibition of PDE10A. This study involved detailed in silico evaluations through docking followed by pharmacological, pharmacophoric, and pharmacokinetic analyses, prioritizing central nervous system (CNS)-active drug criteria. Seven cyclic peptides, those featuring the quinazoline/quinazoline moiety at both termini, exhibited notably enhanced docking scores compared to those of the remaining alkaloids within the screened library. We identified 7 quinolines and 1 quinazoline including Lepadin G, Aspernigerin, CJ-13536, Aurachin A, 2-Undecyl-4(1H)-quinolone, Huajiaosimuline 3-Prenyl-4-prenyloxyquinolin-2-one, and Isaindigotone that followed the standard CNS active drug criteria. The dominant quinoline ring in our study and its related quinazoline were central to our evaluations; therefore, the pharmacophoric features of these scaffolds were highlighted. The top alkaloids met all CNS-active drug properties; while nonmutagenic and without PAINS alerts, many indicated potential hepatotoxicity. Among the compounds, Huajiaosimuline was particularly significant due to its alignment with lead-likeness and CNS-active criteria. Aspernigerin demonstrated its affinity for numerous dopamine receptors, which signifies its potential to alter dopaminergic neurotransmission that is directly related to PD. Interestingly, the majority of these alkaloids had biological targets primarily associated with G protein-coupled receptors, critical in PD pathophysiology. They exhibit superior excretion parameters and toxicity end-points compared to the standard. Notably, selected alkaloids demonstrated stability in the binding pocket of PDE10A according to the molecular dynamic simulation results. Our findings emphasize the potential of these alkaloids as PDE10A inhibitors. Further experimental studies may be necessary to confirm their actual potency in inhibiting PDE10A before exploring their therapeutic potential in PD.

11.
Pak J Pharm Sci ; 26(3): 479-85, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23625420

RESUMEN

In the present work, a series of 2-O-substituted derivatives of 1-[(3,5-dichloro-2-hydroxy phenyl) sulfonyl]piperidine (5a-j) were synthesized. These derivatives were geared up by the coupling of 3,5-dichloro-2-hydroxy benzenesulfonyl chloride (1) with piperidine (2) under dynamic pH control in aqueous media to form parent compound 1-[(3,5-dichloro-2-hydroxyphenyl)sulfonyl]piperidine (3), followed by the substitution at oxygen atom with different electrophiles (4a-j) in the presence of sodium hydride (NaH) and dimethyl formamide (DMF) to give a series of O-substituted derivatives of sulfonamides bearing piperidine nucleus 5a-j. The synthesized O-substituted sulfonamides were spectrally characterized. The bioactivity of all the synthesized compounds were evaluated against lipoxygenase (LOX), acetylcholinesterae (AChE) and butyrylcholinesterase (BChE) enzymes and found to be having talented activity against butyrylcholinesterase enzyme.


Asunto(s)
Piperidinas/síntesis química , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Concentración de Iones de Hidrógeno , Lipooxigenasa/metabolismo , Inhibidores de la Lipooxigenasa/síntesis química , Inhibidores de la Lipooxigenasa/química , Inhibidores de la Lipooxigenasa/farmacología , Oxígeno/química , Piperidinas/química , Piperidinas/farmacología , Compuestos de Sodio/química , Relación Estructura-Actividad
12.
Cureus ; 15(9): e45969, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37900368

RESUMEN

Senior-Loken syndrome (SLS) is a rare autosomal recessive disorder affecting the eyes and the kidneys. It is an extremely rare disorder with an incidence of 1/1,000,000. Like most hereditary disorders, it is more commonly seen in families with consanguineous marriages. Here, we present a case of a 35-year-old male with a complicated past medical history, who presented to us in the outpatient department for kidney transplant consideration. The patient was diagnosed case of Senior-Loken syndrome with a family history of autoimmune diseases, renal disease, and multiple unexplained miscarriages. He also had multiple dialysis access-related complications requiring frequent access changes. He previously had an unrelated pre-emptive renal transplant which resulted in graft failure within 48 hours. In view of his history, a prothrombotic condition was suspected and the patient was started on warfarin. Workup was positive for lupus anticoagulant and hematology recommended lifelong anticoagulation. The patient had a related renal transplant that was successful. He is now on apixaban and has not had any thrombotic complications to date. This patient had antiphospholipid syndrome leading to multiple thrombotic events and a failed graft, but was never worked up for autoimmune disorders despite having a strong family history. His renal disease was presumed to be secondary to a rare condition - Senior-Loken syndrome and he was not investigated for a co-existing condition (e.g., antiphospholipid syndrome {APLS} in this case) which led to early graft failure. Hence when considering a patient for transplant, care should be taken to rule out autoimmune diseases and not ignore possible co-existing conditions in the presence of a renal pathology.

13.
Chempluschem ; 88(5): e202300131, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37221621

RESUMEN

Mixed self-assembled monolayers (mixed SAMs)-based molecular-scale electronic devices in recent years have gained great achievement in the fundamental study on charge transport mechanism and electronic functionalities. This review aims to summarize the preparation and characterization, structure modulation, and applications of heterogeneous mixed SAMs in molecular electronics. One key advantage of SAM-based molecular devices compared to single molecular devices is the ability to tune the intermolecular interactions, and two-dimensional (2-D) assembly structure allows for the optimization of charge transport in desired devices. Herein we review the qualitative and quantitative examination of the nanoscale organization and intermolecular interactions of mixed SAMs obtained by various mixed SAM preparation and characterization techniques. The use of mixed SAMs to control the structural order and compactness of SAM to form high-performance molecular electronic devices is also reviewed. Finally, we wrap up the review by discussing the challenges of this technique for the development of novel electronic functional devices in the future.

14.
Comput Intell Neurosci ; 2023: 9266889, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959840

RESUMEN

To diagnose an illness in healthcare, doctors typically conduct physical exams and review the patient's medical history, followed by diagnostic tests and procedures to determine the underlying cause of symptoms. Chronic kidney disease (CKD) is currently the leading cause of death, with a rapidly increasing number of patients, resulting in 1.7 million deaths annually. While various diagnostic methods are available, this study utilizes machine learning due to its high accuracy. In this study, we have used the hybrid technique to build our proposed model. In our proposed model, we have used the Pearson correlation for feature selection. In the first step, the best models were selected on the basis of critical literature analysis. In the second step, the combination of these models is used in our proposed hybrid model. Gaussian Naïve Bayes, gradient boosting, and decision tree classifier are used as a base classifier, and the random forest classifier is used as a meta-classifier in the proposed hybrid model. The objective of this study is to evaluate the best machine learning classification techniques and identify the best-used machine learning classifier in terms of accuracy. This provides a solution for overfitting and achieves the highest accuracy. It also highlights some of the challenges that affect the result of better performance. In this study, we critically review the existing available machine learning classification techniques. We evaluate in terms of accuracy, and a comprehensive analytical evaluation of the related work is presented with a tabular system. In implementation, we have used the top four models and built a hybrid model using UCI chronic kidney disease dataset for prediction. Gradient boosting achieves around 99% accuracy, random forest achieves 98%, decision tree classifier achieves 96% accuracy, and our proposed hybrid model performs best getting 100% accuracy on the same dataset. Some of the main machine learning algorithms used to predict the occurrence of CKD are Naïve Bayes, decision tree, K-nearest neighbor, random forest, support vector machine, LDA, GB, and neural network. In this study, we apply GB (gradient boosting), Gaussian Naïve Bayes, and decision tree along with random forest on the same set of features and compare the accuracy score.


Asunto(s)
Algoritmos , Aprendizaje Automático , Humanos , Teorema de Bayes , Redes Neurales de la Computación , Bosques Aleatorios , Máquina de Vectores de Soporte
15.
RSC Adv ; 13(43): 30052-30070, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37849696

RESUMEN

Hepatitis C Virus (HCV), affecting millions of people worldwide, is the leading cause of liver disorder, cirrhosis, and hepatocellular carcinoma. HCV is genetically diverse having eight genotypes and several subtypes predominant in different regions of the globe. The HCV NS3/4A protease is a primary therapeutic target for HCV with various FDA-approved antivirals and several clinical developments. However, available protease inhibitors (PIs) have lower potency against HCV genotype 3 (GT3), prevalent in South Asia. In this study, the incumbent computational tools were utilized to understand and explore interactions of the HCV GT3 receptor with the potential inhibitors after the virtual screening of one million compounds retrieved from the ZINC database. The molecular dynamics, pharmacological studies, and experimental studies uncovered the potential PIs as ZINC000224449889, ZINC000224374291, and ZINC000224374456 and the derivative of ZINC000224374456 from the ZINC library. The study revealed that these top-hit compounds exhibited good binding and better pharmacokinetics properties that might be considered the most promising compound against HCV GT3 protease. Viability test, on primary healthy Human Gingival Fibroblasts (HGFs) and cancerous AGS cell line, was also carried out to assess their safety profile after administration. In addition, Surface Plasmon Resonance (SPR) was also performed for the determination of affinity and kinetics of synthesized compounds with target proteins.

16.
ACS Omega ; 8(13): 11952-11965, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37033856

RESUMEN

An array of 1,3,4-oxadiazole hybrids, 7a-s, structurally intriguing cores with potential in natural product synthesis and drug discovery, have been synthesized using innovative comparable conventional and microwave-assisted protocols. The synthesis was performed by the reaction of secondary amine-based acetamides, 6a-s, as the electrophile and piperidine-based oxadiazoles as the nucleophile, 3, under the metal-free reaction conditions. High yield in minimum time with highest purity was obtained by the microwave-irradiated method instead of the conventional one. The structural elucidations were made through infrared, 1H NMR, 13C NMR, and elemental analysis studies. The whole array of synthesized compounds, 7a-s, was evaluated for their potential against α-glucosidase and butyryl cholinesterase (BChE) enzymes. Natural bond orbital and structural optimizations were made by using the B3LYP method and the basis set of 6-311++G(d,p). Frontier molecular orbitals and molecular electrostatic potential were calculated at the same level of selected compounds as potential candidates against BChE and α-glucosidase enzymes utilizing the time-dependent density functional theory. Fifteen compounds out of 19 were observed to be active against α-glucosidase enzyme in comparison with acarbose as the reference standard and 7 against the BChE enzyme compared to eserine as the reference standard. The highest potential of compound 7j against BChE is well correlated by the higher binding interaction with target protein as -10.2, calculated by docking studies. The recruited compounds against both enzymes could be the best anti-enzymatic drugs and part of drugs discovery programs after further analysis.

17.
Toxics ; 11(7)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37505605

RESUMEN

The intake of toxic metals from cooking utensils through food is of growing concern to the medical community. This intake poses serious risk to human health. In many developing countries, different types of contaminated metals scraps are used to make cooking utensils. The leaching of both nutritionally essential and toxic metals in significant quantities from cookware during the cooking process results in food contamination and poses a substantial health risk. In the present study, the leaching of some toxic and potentially toxic metals from cooking utensils into different solutions and food was investigated. A preliminary survey indicated that the majority of individuals tend to use aluminum cookware due to its affordability, overlooking the potential health risks associated with these inexpensive and lower-quality cooking utensils. XRF analysis revealed that aluminum, steel, and copper cookware had K, Ca, Pb, Cd, Ni, V, Sn Mo, Zn, Bi, and Tb as contaminants. In addition, aluminum (3.2 ± 0.25 to 4.64 ± 0.20 g/kg) and copper cookware (2.90 ± 0.12 g/kg) were highly contaminated with lead. The time and pH-dependent study revealed that leaching of metals (Al, Pb, Ni, Cr, Cd, Cu, and Fe, etc.) into food was predominantly from anodized and non-anodized aluminum cookware. More metal leaching was observed from new aluminum cookware compared to old. Acidic food was found to cause more metals to leach during cooking. Blood metal analysis of the local population revealed the presence of high concentrations of Al, Pb, Cd, and Ni. In conclusion, leaching of toxic or potentially toxic metals from cookware into food, especially from anodized and non-anodized aluminum cookware, poses a potential public health risk. Practical applications: Cooking utensils are routinely used for the preparation of food. However, the harmful impact posed by these essential items is largely unknown. The current research briefly explains the toxic metals leaching from cookware in a pH-dependent manner and leaves a message to the public, especially in developing countries like Pakistan, regarding the type of cookware suitable for cooking purposes.

18.
J Med Chem ; 66(3): 1928-1940, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36701569

RESUMEN

Although cyclin-dependent kinase 2 (CDK2) is a validated target for both cancer and contraception, developing a CDK2 inhibitor with exquisite selectivity has been challenging due to the structural similarity of the ATP-binding site, where most kinase inhibitors bind. We previously discovered an allosteric pocket in CDK2 with the potential to bind a selective compound and then discovered and structurally confirmed an anthranilic acid scaffold that binds this pocket with high affinity. These allosteric inhibitors are selective for CDK2 over structurally similar CDK1 and show contraceptive potential. Herein, we describe the screening and optimization that led to compounds like EF-4-177 with nanomolar affinity for CDK2. EF-4-177 is metabolically stable, orally bioavailable, and significantly disrupts spermatogenesis, demonstrating this series' therapeutic potential. This work details the discovery of the highest affinity allosteric CDK inhibitors reported and shows promise for this series to yield an efficacious and selective allosteric CDK2 inhibitor.


Asunto(s)
Anticonceptivos Masculinos , Masculino , Humanos , Animales , Ratones , Quinasa 2 Dependiente de la Ciclina , Relación Estructura-Actividad , Anticonceptivos Masculinos/farmacología , Recuento de Espermatozoides , Semen/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química
19.
Nat Commun ; 14(1): 3213, 2023 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-37270540

RESUMEN

Compared to most ATP-site kinase inhibitors, small molecules that target an allosteric pocket have the potential for improved selectivity due to the often observed lower structural similarity at these distal sites. Despite their promise, relatively few examples of structurally confirmed, high-affinity allosteric kinase inhibitors exist. Cyclin-dependent kinase 2 (CDK2) is a target for many therapeutic indications, including non-hormonal contraception. However, an inhibitor against this kinase with exquisite selectivity has not reached the market because of the structural similarity between CDKs. In this paper, we describe the development and mechanism of action of type III inhibitors that bind CDK2 with nanomolar affinity. Notably, these anthranilic acid inhibitors exhibit a strong negative cooperative relationship with cyclin binding, which remains an underexplored mechanism for CDK2 inhibition. Furthermore, the binding profile of these compounds in both biophysical and cellular assays demonstrate the promise of this series for further development into a therapeutic selective for CDK2 over highly similar kinases like CDK1. The potential of these inhibitors as contraceptive agents is seen by incubation with spermatocyte chromosome spreads from mouse testicular explants, where they recapitulate Cdk2-/- and Spdya-/- phenotypes.


Asunto(s)
Quinasa 2 Dependiente de la Ciclina , Ciclinas , Inhibidores de Proteínas Quinasas , Animales , Ratones , Anticoncepción , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Ciclinas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Relación Estructura-Actividad
20.
Antibiotics (Basel) ; 11(4)2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35453267

RESUMEN

The high rates of bacterial infections affect the economy worldwide by contributing to the increase in morbidity and treatment costs. The present cross-sectional study was carried out to evaluate the prevalence of bacterial infection in urinary tract infection (UTI) patients and to evaluate the antimicrobial resistance rate (AMR) in a Tertiary Care Hospital in Lahore, Pakistan. The study was conducted for the period of one year from January 2020 to December 2020. A total of 1899 different clinical samples were collected and examined for bacterial cultures using standard procedures. Samples were inoculated on different culture media to isolate bacterial isolates and for identification and susceptibility testing. A total of 1107/1899 clinical samples were positive for Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli) and other bacterial isolates. Methicillin-resistant S. aureus (MRSA) prevalence was 16.93% from these positive cases. MRSA strains were found to be highly resistant to amikacin, clindamycin, fusidic acid, gentamicin and tobramycin, while highest sensitivity was noted against vancomycin (100%) and linezolid (100%). MRSA and high rates of multidrug resistance (MDR) pose a serious therapeutic burden to critically ill patients. A systematic and concerted effort is essential to rapidly identify high-risk patients and to reduce the burden of AMR.

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