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1.
Bioorg Med Chem Lett ; 113: 129971, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39306048

RESUMEN

Hepatocellular carcinoma (HCC) is considered as one of the leading causes of death in liver disease patients. Several signal transduction pathways are involved in HCC pathogenesis. Multikinase inhibitors (MKIs) show beneficial effects for HCC and the FDA approved a few MKIs including sorafenib, lenvatinib for HCC treatments. Here, a novel series of phenylacetamide derivatives were designed, synthesized and evaluated as multikinase inhibitors. Several compounds showed nanomolar IC50 values against FLT1, FLT3, FLT4, KDR, PDGFRα, PDGFRß. The compounds were tested against human hepatocellular carcinoma (HCC), human colon adenocarcinoma and human gastric carcinoma cell lines. With favorable pharmacokinetics profiles, compound 12 and compound 14 were selected for in vivo efficacy studies in Hep3B mice models and demonstrated efficacious than sorafenib.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Inhibidores de Proteínas Quinasas , Animales , Humanos , Ratones , Acetamidas/química , Acetamidas/síntesis química , Acetamidas/farmacología , Acetamidas/farmacocinética , Administración Oral , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Estructura Molecular , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Relación Estructura-Actividad , Oxazoles/química , Oxazoles/farmacología , Bencimidazoles/química , Bencimidazoles/farmacología , Bencenoacetamidas/química , Bencenoacetamidas/farmacología
2.
RSC Med Chem ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39246743

RESUMEN

Lung cancer is a leading cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC) accounts for the major portion (80-85%) of all lung cancer cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are commonly used as the targeted therapy for EGFR-mutated NSCLC. The FDA has approved first-, second- and third-generation EGFR-TKIs as therapeutics options. Osimertinib, the third-generation irreversible EGFR-TKI, has been approved for the treatment of NSCLC patients with the EGFRT790M mutation. However, due to the EGFRC797S mutation in the kinase domain of EGFR, resistance to osimertinib is observed and that limits the long-term effectiveness of the drug. The C797S mutation is one of the major causes of drug resistance against the third-generation EGFR TKIs. The C797S mutations including EGFR double mutations (19Del/C797S or L858R/C797S) and or EGFR triple mutations (19Del/T790M/C797S or L858R/T790M/C797S) cause major resistance to the third-generation EGFR-TKIs. Therefore, the discovery and development of fourth-generation EGFR-TKIs to target triple mutant EGFR with C797S mutation is a challenging topic in medicinal chemistry research. In this review, we discuss the discovery of novel fourth-generation EGFR TKIs, medicinal chemistry approaches and the strategies to overcome the C797S mutations. In vitro activities of EGFR-TKIs (2019-2024) against mutant EGFR TK, anti-proliferative activities, structural modifications, binding modes of the inhibitors and in vivo efficacies in animal models are discussed here.

3.
Indian J Public Health ; 68(2): 239-242, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38953812

RESUMEN

INTRODUCTION: India has run a nationwide vaccination campaign against COVID-19, which has recently introduced a precaution (third) dose for health workers. This study assessed the perception and attitude of health workers toward the Indian vaccination campaign against COVID-19, with an emphasis on this major change. MATERIALS AND METHODS: A printed questionnaire was distributed among health-care workers at the Medical College of West Bengal. The completed forms were analyzed. RESULTS: Most of the participants were doctors (83.7%). Although all had received two doses of vaccine before, 44.4% were unwilling to be vaccinated with the third dose in the present scenario. The majority (63.8%) of the patients were concerned about side effects. The emergence of new COVID strains (65.6%) was viewed as a threat to the effectiveness of the vaccines. Participants with higher age, comorbidities, and those with the perception that the third dose was being introduced appropriately and would be effective against newer strains of the vaccine tended to be more willing to get vaccinated with the precaution dose compared to their counterparts. CONCLUSION: A dilemma regarding the acceptance of precaution doses was noted among health workers. This warrants the availability of more comprehensive information to increase acceptance of these vaccines.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Personal de Salud , Humanos , India , Vacunas contra la COVID-19/administración & dosificación , Masculino , COVID-19/prevención & control , Femenino , Adulto , Personal de Salud/psicología , SARS-CoV-2 , Actitud del Personal de Salud , Persona de Mediana Edad , Encuestas y Cuestionarios , Vacunación/psicología , Adulto Joven , Vacilación a la Vacunación/psicología
4.
Chem Asian J ; 19(20): e202400629, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39041342

RESUMEN

Levodopa, a widely prescribed drug in Parkinson's disease treatment, stands as the foremost prodrug of dopamine. An affordable self-testing kit is utilized to monitor levodopa content in anti-parkinson drugs in human serum. A photoluminescent trinuclear Zn(II) complex [Zn3(L)2(κ1-OAc)2(κ2-OAc)2] has been synthesized, which cleaves into mononuclear ZC in aqueous solution. ZC was found to detect L-Dopa in Tris-HCl buffer, exhibiting a moderate decrease in PL-emission. The real-life utility of the ZC probe is limited, for its lower sensitivity (LOD 35.3 µM) and separation challenges. Therefore, an interface between homogeneous and heterogeneous supports has been explored, leading to the strategic development of NGOZC, where ZC was grafted onto NGOQD (Graphene oxide quantum dots). This material enables naked- eye detection under both ambient and UV light with color change from bright cyan to green, followed by dark. The nitrogen doping effect was investigated by several comparative investigations involving the synthesis of ZC-grafted GOQD, leading to enhanced quenching performance. Steady-state and time-resolved fluorescence titration study, morphological analysis, and computational calculations have been performed to get insights into the sensing mechanism. To the best of our knowledge, this as-synthesized NGOZC (LOD 1.78 nM) represents a promising strategy and platform for applications in biosensors, especially for Parkinson's and Alzheimer's diseases.


Asunto(s)
Grafito , Enfermedad de Parkinson , Puntos Cuánticos , Zinc , Enfermedad de Parkinson/tratamiento farmacológico , Zinc/química , Humanos , Puntos Cuánticos/química , Grafito/química , Levodopa/química , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Nitrógeno/química , Nanoestructuras/química , Luminiscencia
5.
Nanoscale Horiz ; 9(9): 1522-1531, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-38954430

RESUMEN

Spintronics-based artificial neural networks (ANNs) exhibiting nonvolatile, fast, and energy-efficient computing capabilities are promising neuromorphic hardware for performing complex cognitive tasks of artificial intelligence and machine learning. Early experimental efforts focused on multistate device concepts to enhance synaptic weight precisions, albeit compromising on cognitive accuracy due to their low magnetoresistance. Here, we propose a hybrid approach based on the tuning of tunnel magnetoresistance (TMR) and the number of states in the compound magnetic tunnel junctions (MTJs) to improve the cognitive performance of an all-spin ANN. A TMR variation of 33-78% is controlled by the free layer (FL) thickness wedge (1.6-2.6 nm) across the wafer. Meanwhile, the number of resistance states in the compound MTJ is manipulated by varying the number of constituent MTJ cells (n = 1-3), generating n + 1 states with a TMR difference between consecutive states of at least 21%. Using MNIST handwritten digit and fashion object databases, the test accuracy of the compound MTJ ANN is observed to increase with the number of intermediate states for a fixed FL thickness or TMR. Meanwhile, the test accuracy for a 1-cell MTJ increases linearly by 8.3% and 7.4% for handwritten digits and fashion objects, respectively, with increasing TMR. Interestingly, a multifarious TMR dependence of test accuracy is observed with the increasing synaptic complexity in the 2- and 3-cell MTJs. By leveraging on the bimodal tuning of multilevel and TMR, we establish viable paths for enhancing the cognitive performance of spintronic ANN for in-memory and neuromorphic computing.

6.
Sci Adv ; 10(26): eadl2492, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38924395

RESUMEN

Bioproduction of 1-alkenes from naturally abundant free fatty acids offers a promising avenue toward the next generation of hydrocarbon-based biofuels and green commodity chemicals. UndB is the only known membrane-bound 1-alkene-producing enzyme, with great potential for 1-alkene bioproduction, but the enzyme exhibits limited turnovers, thus restricting its widespread usage. Here, we explore the molecular basis of the limitation of UndB activity and substantially improve its catalytic power. We establish that the enzyme undergoes peroxide-mediated rapid inactivation during catalysis. To counteract this inactivation, we engineered a chimeric membrane enzyme by conjugating UndB with catalase that protected UndB against peroxide and enhanced its number of turnovers tremendously. Notably, our chimeric enzyme is the only example of a membrane enzyme successfully engineered with catalase. We subsequently constructed a whole-cell biocatalytic system and achieved remarkable efficiencies (up to 95%) in the biotransformation of a wide range of fatty acids (both aliphatic and aromatic) into corresponding 1-alkenes with numerous biotechnological applications.


Asunto(s)
Alquenos , Biocatálisis , Catalasa , Alquenos/metabolismo , Catalasa/genética , Catalasa/metabolismo , Ácidos Grasos/metabolismo , Ingeniería de Proteínas/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/genética
7.
Dalton Trans ; 53(23): 9979-9994, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38812408

RESUMEN

Herein, we present a dark-green crystalline tetranuclear Cu(II) Schiff base complex {C1 = [Cu4L4](ClO4)4(DMF)4(H2O)} using a N,N,O donor ligand (HL), namely 2-(((2-hydroxypropyl)imino)methyl)-6-methoxyphenol. Spectro-photometrical investigation on the ß-lactamase-like activity of this coordinately saturated system revealed its catalytic inefficiency towards hydrolysis of nitrocefin as a model substrate. This complex has attracted significant interest as a promising photo-catalyst owing to its narrow band gap (2.40 eV) as predicted from DFT calculations and its higher responsivity towards UV light. Therefore, C1 is effectively involved in the photocatalytic reduction of perchlorate to Cl- in the presence of a hole scavenger (H2O-MeOH) under prolonged UV irradiation and itself becomes photo-cleaved to yield a new dark-brown colored chlorobridged dinuclear crystalline complex C2 {[CuL(H2O)2Cl3]H2O}. Furthermore, C2 was deployed as a functional ß-lactamase model and was found to show a remarkable catalytic proficiency towards the hydrolysis of nitrocefin in 70 : 30 (V/V) MeOH-H2O medium. This pro-catalyst C2 has been speculated to generate an aqua bridged active catalyst that plays a crucial factor in hydrolysis. This phenomenon was again experimentally established by potentiometric pH titration where C2 displays only one pKa value (7.11) in the basic pH range, indicating the deprotonation of the bridged water molecule. Based on several other kinetic studies, it may be postulated that the hydrolysis of nitrocefin is initiated by the nucleophilic attack of a bridging hydroxide, followed by very fast protonation of the intermediate to furnish the hydrolyzed product. It is noteworthy that the rate of nitrocefin hydrolysis is greatly inhibited in the presence of external chloride concentration. To the best of our knowledge, this is the first report on the photochemical behavior of such a tetranuclear copper(II) Schiff base complex. Our current interest is focused on inventing a potent ß-lactamase inhibitory therapeutic as well as elucidating its mechanism through comprehensive chemical analysis.


Asunto(s)
Complejos de Coordinación , Cobre , Teoría Funcional de la Densidad , Procesos Fotoquímicos , Rayos Ultravioleta , beta-Lactamasas , Cobre/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , beta-Lactamasas/metabolismo , beta-Lactamasas/química , Inhibidores de beta-Lactamasas/química , Inhibidores de beta-Lactamasas/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Hidrólisis , Farmacorresistencia Microbiana , Estructura Molecular
8.
Indian J Surg Oncol ; 15(Suppl 2): 238-248, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38817989

RESUMEN

Some dietary elements, tobacco use, have long been suspected as risk factors for gall bladder carcinoma. The objective of the study was to describe the dietary pattern of the patients with gall bladder carcinoma and to compare the dietary ingredients, and addiction between the cases and controls. Fifty-six gall bladder carcinoma cases and 56 matched controls were compared for diet and addiction patterns. Fried food, junk food, vanaspati, frozen fish, dried fish, red meat, kheer, milled mustard oil, puffed rice containing urea, chili powder, less water consumption, extra salt, tobacco exposure, betel leaf, and alcohol consumption were significantly related with gall bladder carcinoma. Green tea, sunflower oil, butter, ghee, fish intake more than twice weekly, sea fish, packaged milk, some fruits, and vegetables were found protective. Some dietary elements and addiction are related to gall bladder carcinoma, whereas some food items have a protective role.

9.
Nat Commun ; 15(1): 4132, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755165

RESUMEN

The regulated release of chemical messengers is crucial for cell-to-cell communication; abnormalities in which impact coordinated human body function. During vesicular secretion, multiple SNARE complexes assemble at the release site, leading to fusion pore opening. How membrane fusion regulators act on heterogeneous SNARE populations to assemble fusion pores in a timely and synchronized manner, is unknown. Here, we demonstrate the role of SNARE chaperones Munc13-1 and Munc18-1 in rescuing individual nascent fusion pores from their diacylglycerol lipid-mediated inhibitory states. At the onset of membrane fusion, Munc13-1 clusters multiple SNARE complexes at the release site and synchronizes release events, while Munc18-1 stoichiometrically interacts with trans-SNARE complexes to enhance N- to C-terminal zippering. When both Munc proteins are present simultaneously, they differentially access dynamic trans-SNARE complexes to regulate pore properties. Overall, Munc proteins' direct action on fusion pore assembly indicates their role in controlling quantal size during vesicular secretion.


Asunto(s)
Fusión de Membrana , Proteínas Munc18 , Proteínas del Tejido Nervioso , Proteínas SNARE , Animales , Ratas , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Proteínas Munc18/metabolismo , Proteínas Munc18/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas SNARE/metabolismo , Proteínas SNARE/genética
10.
ACS Appl Mater Interfaces ; 16(8): 10335-10343, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38376994

RESUMEN

The quest to mimic the multistate synapses for bioinspired computing has triggered nascent research that leverages the well-established magnetic tunnel junction (MTJ) technology. Early works on the spin transfer torque MTJ-based artificial neural network (ANN) are susceptible to poor thermal reliability, high latency, and high critical current densities. Meanwhile, work on spin-orbit torque (SOT) MTJ-based ANN mainly utilized domain wall motion, which yields negligibly small readout signals differentiating consecutive states and has designs that are incompatible with technological scale-up. Here, we propose a multistate device concept built upon a compound MTJ consisting of multiple SOT-MTJs (number of MTJs, n = 1-4) on a shared write channel, mimicking the spin-based ANN. The n + 1 resistance states representing varying synaptic weights can be tuned by varying the voltage pulses (±1.5-1.8 V), pulse duration (100-300 ns), and applied in-plane fields (5.5-10.5 mT). A large TMR difference of more than 13.6% is observed between two consecutive states for the 4-cell compound MTJ, a 4-fold improvement from reported state-of-the-art spin-based synaptic devices. The ANN built upon the compound MTJ shows high learning accuracy for digital recognition tasks with incremental states and retraining, achieving test accuracy as high as 95.75% in the 4-cell compound MTJ. These results provide an industry-compatible platform to integrate these multistate SOT-MTJ synapses directly into neuromorphic architecture for in-memory and unconventional computing applications.

11.
World J Pediatr Congenit Heart Surg ; 15(4): 439-445, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38263667

RESUMEN

Background: Treatment of congenital heart disease (CHD), being the most common congenital anomaly, puts immense financial burden in low- and middle-income countries (LMICs) and contributes significantly to infant mortality. We report experiences of treatment of CHD in the Indian state of West Bengal by a public-private partnership (PPP) model. Methods: Under the Rashtriya Bal Swasthya Karyakram, the government of the state of West Bengal in India launched a program called the "Sishu Sathi Scheme" to provide free treatment to children who need heart surgeries, irrespective of economic status. Treatment was provided in selected private hospitals and some public hospitals in a reimbursement model where government compensated the hospitals. Data were collected on such procedures from 2013 to 2022 and analyzed. Results: A total of 27,844 patients with CHD received treatment under the Sishu Sathi Scheme from August 2013 to December 2022. The average number of patients per year was 3,093. Detailed data of procedures from January 2016 to December 2022 showed a total of 22,572 procedures (6,249 device interventions, 4,840 cardiac catheterizations, and 11,483 surgical interventions). The in-hospital mortality of surgical procedures and catheterization lab procedures were 5.2% and 0.9%, respectively. Conclusions: A large number of patients with CHD were successfully treated under a PPP in the state of West Bengal in India. In spite of its inherent challenges, this model is of special relevance in LMICs where access and affordability for treatment of CHD always remain a challenge.


Asunto(s)
Cardiopatías Congénitas , Asociación entre el Sector Público-Privado , Humanos , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/terapia , India , Asociación entre el Sector Público-Privado/organización & administración , Lactante , Masculino , Femenino , Procedimientos Quirúrgicos Cardíacos/estadística & datos numéricos , Procedimientos Quirúrgicos Cardíacos/economía , Recién Nacido , Preescolar , Estudios Retrospectivos , Niño
12.
Life Sci Alliance ; 7(4)2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38238088

RESUMEN

The precise cell-to-cell communication relies on SNARE-catalyzed membrane fusion. Among ∼70 copies of synaptobrevin2 (syb2) in synaptic vesicles, only ∼3 copies are sufficient to facilitate the fusion process at the presynaptic terminal. It is unclear what dictates the number of SNARE complexes that constitute the fusion pore assembly. The structure-function relation of these dynamic pores is also unknown. Here, we demonstrate that syb2 monomers and dimers differentially engage in regulating the trans-SNARE assembly during membrane fusion. The differential recruitment of two syb2 structures at the membrane fusion site has consequences in regulating individual nascent fusion pore properties. We have identified a few syb2 transmembrane domain residues that control monomer/dimer conversion. Overall, our study indicates that syb2 monomers and dimers are differentially recruited at the release sites for regulating membrane fusion events.


Asunto(s)
Fusión de Membrana , Proteínas SNARE , Fusión de Membrana/fisiología , Proteínas SNARE/genética , Sinapsis , Comunicación Celular , Terminales Presinápticos
13.
Protein Sci ; 33(2): e4893, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38160318

RESUMEN

Integral membrane enzymes play essential roles in a plethora of biochemical processes. The fatty acid desaturases (FADS)-like superfamily is an important group of integral membrane enzymes that catalyze a wide array of reactions, including hydroxylation, desaturation, and cyclization; however, due to the membrane-bound nature, the majority of these enzymes have remained poorly understood. UndB is a member of the FADS-like superfamily, which catalyzes fatty acid decarboxylation, a chemically challenging reaction at the membrane interface. UndB reaction produces terminal olefins that are prominent biofuel candidates and building blocks of polymers with widespread industrial applications. Despite the great importance of UndB for several biotechnological applications, the enzyme has eluded comprehensive investigation. Here, we report details of the expression, solubilization, and purification of several constructs of UndB to achieve the optimally functional enzyme. We gained important insights into the biochemical, biophysical, and catalytic properties of UndB, including the thermal stability and factors influencing the enzyme activity. Additionally, we established the ability and kinetics of UndB to produce dienes by performing di-decarboxylation of diacids. We found that the reaction proceeds by forming a mono-carboxylic acid intermediate. Our findings shed light on the unexplored biochemical properties of the UndB and extend opportunities for its rigorous mechanistic and structural characterization.


Asunto(s)
Alquenos , Ácidos Grasos , Alquenos/química , Alquenos/metabolismo , Ácidos Grasos/química , Hidroxilación , Ácidos Carboxílicos
14.
Nat Commun ; 14(1): 7761, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012142

RESUMEN

Synaptotagmin-1 and synaptotagmin-7 are two prominent calcium sensors that regulate exocytosis in neuronal and neuroendocrine cells. Upon binding calcium, both proteins partially penetrate lipid bilayers that bear anionic phospholipids, but the specific underlying mechanisms that enable them to trigger exocytosis remain controversial. Here, we examine the biophysical properties of these two synaptotagmin isoforms and compare their interactions with phospholipid membranes. We discover that synaptotagmin-1-membrane interactions are greatly influenced by membrane order; tight packing of phosphatidylserine inhibits binding due to impaired membrane penetration. In contrast, synaptotagmin-7 exhibits robust membrane binding and penetration activity regardless of phospholipid acyl chain structure. Thus, synaptotagmin-7 is a super-penetrator. We exploit these observations to specifically isolate and examine the role of membrane penetration in synaptotagmin function. Using nanodisc-black lipid membrane electrophysiology, we demonstrate that membrane penetration is a critical component that underlies how synaptotagmin proteins regulate reconstituted, exocytic fusion pores in response to calcium.


Asunto(s)
Calcio , Sinaptotagmina I , Sinaptotagminas/metabolismo , Calcio/metabolismo , Sinaptotagmina I/metabolismo , Exocitosis/fisiología , Membrana Celular/metabolismo , Proteínas de Unión al Calcio/metabolismo , Fosfolípidos/metabolismo
15.
Chem Asian J ; 18(22): e202300654, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37818755

RESUMEN

Two Zn(II)-based compounds, [Zn2 L1 (OAc)3 (MeOH)] (1) and [Zn2 L2 (OAc)3 ]n (2), have been reported where HL1 is (E)-4-bromo-2-methoxy-6-(((2-morpholino ethyl)imino) methyl)phenol and HL2 is (E)-4-bromo-2-methoxy-6-(((2-(piperazine-1-yle)ethyl)imino)methyl) phenol. Single-crystal X-ray diffraction (SCXRD) analysis unveils vivid change in structural arrangements and dimensionality from 1 to 2 due to change in coordinated atom from oxygen to nitrogen of the ligands. SCXRD study shows that compound 1 is dinuclear but compound 2 has a 1-dimensional polymeric structure having helical chain. Structural diversity greatly influences the catalytic activity. Compound 1 acts as excellent catalyst for conversion of 3, 5-di-tert-butyl catechol (3, 5-DTBC) to 3, 5-di-tert-butylbenzoquinone (3, 5-DTBQ) with the turnover number (kcat ) value of 34.94 sec-1 . Further, compound 1 reveals phosphatase like activity for conversion of disodium salt of (4-nitrophenyl)-phosphate hexahydrate to p-nitrophenolate with the kcat value of 24.64 sec-1 . Interestingly, compound 2 does not show any catalytic activity. To correlate this distinctly different catalytic behavior of two compounds, DFT calculation was carried out. The calculation reveals that detachment of coordinated methanol from coordination sphere of zinc in compound 1 is energetically favourable which creates room for substrate binding, resulting in high catalytic activity. By contrast, in compound 2, detachment of piperazine or Zn-O of -COOH group is energetically unfavourable, resulting in no catalytic activity.

16.
Sci Rep ; 13(1): 18039, 2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37865670

RESUMEN

The detection and discrimination of Fe2+ and Fe3+ ions have been investigated using a simple probe (L), produced by the condensation of ethylenediamine and 3-ethoxysalicyaldehyde. Single crystal X-ray structures demonstrate that L interacts with Fe2+ and Fe3+. In aqueous-DMSO media, the L recognises AsO2- by fluorescence and colorimetry techniques. The AsO2- aided PET inhibition and H-bond assisted chelation enhanced fluorescence (CHEF) boost fluorescence by 91-fold. The L can detect 0.354 ppb Fe2+, 0.22 ppb Fe3+ and 0.235 ppt AsO2-.

17.
ACS Appl Bio Mater ; 6(8): 3278-3290, 2023 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-37565455

RESUMEN

This work delivers a targeted synthesis of four isostructural O-substituted imidazole-based zinc(II) complexes, namely, [Zn2(L1)2(I)2](DMF) (1), [Zn2(L2)2(I)2](DMF) (2), [Zn2(L1)2(Br)2] (3), and [Zn2(L2)2(Br)2] (4), derived from homologous Schiff-base ligands HL1 and HL2 to explore their impact on free radicals, microbes, and dephosphorylation of phosphoesters. The antioxidant activity of all complexes was checked by various radical scavenging assays (ABTS+•, DPPH•, and H2O2 radical quenching). Among them, complex 2 showed superior radical quenching activity, as indicated by its lowest EC50 value and thus maximum antioxidative capability. Again, antibacterial assays against several Gram-positive and Gram-negative bacteria were conducted to evaluate the zone of inhibition. The minimum bactericidal concentration and minimum inhibitory concentration values from the microdilution method for all complexes revealed complex 3 to have maximum potency against Gram-positive bacteria. The P-O bond hydrolysis in the phospholipid chain caused by the hydrolytic phosphoesterase activity of the Zn(II)-complexes plays a crucial role in cell membrane rupture. A model substrate 4-PNPP was used to explain the potency of monomeric Zn(II) complex (3) for cell penetration over dimeric one (2) with a proper mechanism. Furthermore, a heme model substrate, Fe(TPP)Cl, has been introduced with the most potent complex 3 and has spectrophotometric evidence for covalent interaction with imidazole and Fe(III) that can disrupt the nitric oxide dioxygenase function of flavohemoglobin, leading to bacterial cell death. To our knowledge, this is the first case to report a novel mechanism of antimicrobial action where both the metal and the ligand are cooperatively involved in bacterial cell death. The main goal of this work is to invent multifunctional therapeutics as well as the proper chemical rationalization of biological processes using mechanistic approaches, which includes investigating the roles of halides, imidazoles, and solution-phase structural variations of complexes..


Asunto(s)
Antibacterianos , Compuestos Férricos , Antibacterianos/química , Peróxido de Hidrógeno , Bacterias Gramnegativas , Bacterias Grampositivas , Imidazoles/farmacología , Imidazoles/química , Zinc/farmacología , Zinc/química , Antioxidantes/química , Radicales Libres , Bacterias
18.
Indian J Public Health ; 67(2): 215-220, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37459015

RESUMEN

Background: Domestic work being unrecognized as a formal form of occupation in India, workers are often deprived of basic social security, including access to proper health care. Self-negligence coupled with societal neglect makes them vulnerable to injury and a variety of illnesses. Objectives: We aimed to study the morbidity pattern of women domestic workers residing in a slum area of Kolkata, West Bengal, India. Materials and Methods: An observational descriptive cross-sectional study was carried out by interviewing and clinically examining 106 randomly selected women domestic workers. Results: The majority (82.08%) had health complaints: heart burn being most common (40.57%). Musculoskeletal and dermatological issues were common. Anemia (31.25%) was a common prediagnosed morbidity. Pallor (33.96%) and dental caries (31.13%) were common; 50.94% reported workplace injury. Of those having complaints, 77.36% sought health care, 59.43% of whom relied on health facilities. Lack of time (54.05%), felt need (35.14%) and money (21.62%) affected adequate care seeking. Participants with cardiorespiratory complaints tended to visit health facilities significantly more (P < 0.05). Conclusion: Health vulnerabilities and neglectful behavior among domestic workers are evident, making the need to sensitize them about their health risks and ways to overcome such issues very vital. Awareness should also be generated about government health schemes to encourage timely health checkup and necessary intervention.


Asunto(s)
Caries Dental , Humanos , Femenino , Estudios Transversales , India/epidemiología , Aceptación de la Atención de Salud , Morbilidad
19.
ACS Med Chem Lett ; 14(6): 727-736, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37312837

RESUMEN

Prostaglandin E2 (PGE2) receptor 4 (EP4) is one of four EP receptors commonly upregulated in the tumor microenvironment and plays vital roles in stimulating cell proliferation, invasion, and metastasis. Biochemical blockade of the PGE2-EP4 signaling pathway is a promising strategy for controlling inflammatory and immune related disorders. Recently combination therapies of EP4 antagonists with anti-PD-1 or chemotherapy agents have emerged in clinical studies for lung, breast, colon, and pancreatic cancers. Herein, a novel series of indole-2-carboxamide derivatives were identified as selective EP4 antagonists, and SAR studies led to the discovery of the potent compound 36. Due to favorable pharmacokinetics properties and good oral bioavailability (F = 76%), compound 36 was chosen for in vivo efficacy studies. Compound 36 inhibited tumor growth in a CT-26 colon cancer xenograft better than E7046 and a combination of 36 with capecitabine significantly suppressed tumor growth (TGI up to 94.26%) in mouse models.

20.
ACS Appl Mater Interfaces ; 15(22): 26442-26456, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37232423

RESUMEN

The progression of a new class of compounds to inhibit the uncontrolled proliferation of carcinoma cells has become one of the most powerful weapons to combat "cancer". To this end, a new Mn(II)-based metal-organic framework, namely, [{Mn(5N3-IPA)(3-pmh)}(H2O)]α (5N3H2-IPA = 5-azidoisophthalic acid and 3-pmh = (3-pyridylmethylene)hydrazone), has been synthesized adopting a mixed ligand approach and exploited as a successful anticancer agent via systematic in vitro and in vivo studies. Single-crystal X-ray diffraction analyses depict that MOF 1 exhibits a 2D pillar-layer structure consisting of water molecules in each 2D void space. Due to the insolubility of the as-synthesized MOF 1, a green hand grinding methodology has been adopted to scale down the particle size to the nanoregime keeping its structural integrity intact. The nanoscale metal-organic framework (NMOF 1) adopts a discrete spherical morphology as affirmed by scanning electron microscopic analysis. The photoluminescence studies revealed that NMOF 1 is highly luminescent, enhancing its biomedical proficiency. Initially, the affinity of the synthesized NMOF 1 for GSH-reduced has been evaluated by various physicochemical techniques. NMOF 1 constrains the proliferation of cancer cells in vitro by inducing G2/M seizure and accordingly leads to apoptotic cell death. More significantly, compared to cancer cells, NMOF 1 exhibits less cytotoxicity against normal cells. It has been demonstrated that NMOF 1 interacts with GSH, causing a drop in cellular GSH levels and the production of intercellular ROS. It is quite intriguing that we discovered that NMOF 1-mediated ROS generation aids in significantly modifying the mitochondrial redox status, which is a crucial factor in apoptosis. According to mechanistic research, NMOF 1 increases the production of proapoptotic proteins and lowers the expression of antiapoptotic proteins, which significantly aids in activating caspase 3 and the subsequent cleavage of PARP1 and cell death via intrinsic apoptotic pathways. Finally, an in vivo investigation using immuno-competent syngeneic mice demonstrates that NMOF 1 can stop tumor growth without causing adverse side effects.


Asunto(s)
Antineoplásicos , Estructuras Metalorgánicas , Neoplasias de la Mama Triple Negativas , Humanos , Animales , Ratones , Especies Reactivas de Oxígeno/metabolismo , Estructuras Metalorgánicas/farmacología , Estructuras Metalorgánicas/química , Apoptosis , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Línea Celular Tumoral , Puntos de Control de la Fase G2 del Ciclo Celular , Antineoplásicos/farmacología , Antineoplásicos/química , Glutatión/farmacología
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