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1.
J Inorg Biochem ; 257: 112598, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38763101

RESUMO

In this work, we report on the synthesis of a novel zinc(II) coordination compound [ZnL2] (1), which was readily obtained from the reaction of Zn(OAc)·2H2O and N'-(pyridin-2-ylmethylene)nicotinohydrazide (HL) in methanol. Recrystallization of 1 from dimethylformamide under ambient conditions allowed to produce yellow block-like crystals of 1·H2O. Complex 1·H2O was characterized by FT-IR and 1H NMR spectroscopy, while its optical properties were studied by UV-vis and spectrofluorimetry in methanol. The crystal structure of the title complex was revealed by single crystal X-ray diffraction and further explored in detail by the Hirshfeld surface analysis. Theoretical investigations based on the DFT calculations have also been applied to show the electronic properties of complex 1. The antitumor activities of the parent ligand HL and complex 1 were studied using Dalton's lymphoma malignant cancer model. Both compounds were found to induce concentration-dependent cytotoxicity and apoptotic cell death, leading to a decrease in cell viability, body weight, and tumor volume in mice with the superior activity of complex 1 over HL. Mice treated with complex 1 demonstrated an increase in life span with a survival period of 23 days. Finally, using a molecular docking approach, we have probed complex 1 to inhibit the recombinant mouse tumor-necrosis factor alpha (mTNF).


Assuntos
Antineoplásicos , Complexos de Coordenação , Zinco , Zinco/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Animais , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Humanos , Cristalografia por Raios X , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos
2.
ACS Sens ; 8(9): 3307-3319, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37540230

RESUMO

With the expansion of the Internet-of-Things (IoT), the use of gas sensors in the field of wearable technology, smart devices, and smart homes has increased manifold. These gas sensors have two key applications─one is the detection of gases present in the environment and the other is the detection of Volatile Organic Compounds (VOCs) that are found in the breath. In this review, we focus systematically on the advancements in the field of various spectroscopic methods such as mass spectrometry-based analysis and point-of-care approach to detect VOCs and gases for environmental monitoring and disease diagnosis. Additionally, we highlight the development of smart sensors that work on the principle of electrochemical detection and provide examples of the same through an extensive literature review. At the end of this review, we highlight various challenges and future perspectives.


Assuntos
Líquidos Corporais , Compostos Orgânicos Voláteis , Dispositivos Eletrônicos Vestíveis , Gases/análise , Líquidos Corporais/química , Compostos Orgânicos Voláteis/análise , Espectrometria de Massas
3.
Probiotics Antimicrob Proteins ; 15(6): 1596-1607, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36593373

RESUMO

The study focuses on the isolation, characterization, and expression analysis of a lectin from the hepatopancreas of Macrobrachium rosenbergii. The protein was isolated by affinity chromatography on a melibiose-agarose column. The molecular weight of the native protein was found to be ~120 kDa which consists of a single polypeptide of ~39.5 kDa. On mass spectrometric analysis, the protein was identified as lipopolysaccharide- and beta-1,3-glucan binding protein (LGBP). LGBP showed hemagglutination with rabbit RBC like a lectin and its carbohydrate-binding specificity was determined by the hemagglutination inhibition test. The protein also showed antibacterial activity against two Gram-negative bacteria Vibrio harveyi and Aeromonas sobria, and one Gram positive bacteria Bacillus cereus in the disc diffusion test. Rabbit antiserum was raised against the purified LGBP and used to develop a sandwich ELISA system for quantitation of the protein in hepatopancreas and serum samples of M. rosenbergii. The expression of the LGBP transcripts in muscle, hepatopancreas, and gill tissues from M. rosenbergii juveniles at 72 h post-challenge of V. harveyi was not modulated as noticed in qPCR analysis. However, significant increases in the concentrations of LGBP protein in hepatopancreas (5.23 ± 0.45 against 3.43 ± 0.43 mg/g tissue in control) and serum (1.08 ± 0.14 against 0.61 ± 0.08 µg/ml in control) were observed in the challenged group of prawns in ELISA suggesting its putative role against bacterial infections. The study for the first time characterized the native LGBP of M. rosenbergii showing a multifunctional role in immunity.


Assuntos
Palaemonidae , Animais , Coelhos , Lipopolissacarídeos/metabolismo , Hepatopâncreas , Lectinas
4.
J Phys Chem Lett ; 13(36): 8564-8572, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36069730

RESUMO

Cancer cells secrete extracellular vesicles (EVs) covered with a carbohydrate polymer, hyaluronan (HA), linked to tumor malignancy. Herein, we have unravelled the contour lengths of HA on a single cancer cell-derived EV surface using single-molecule force spectroscopy (SMFS), which divulges the presence of low molecular weight HA (LMW-HA < 200 kDa). We also discovered that these LMW-HA-EVs are significantly more elastic than the normal cell-derived EVs. This intrinsic elasticity of cancer EVs could be directly allied to the LMW-HA abundance and associated labile water network on EV surface as revealed by correlative SMFS, hydration dynamics with fluorescence spectroscopy, and molecular dynamics simulations. This method emerges as a molecular biosensor of the cancer microenvironment.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Ácido Hialurônico/química , Peso Molecular , Microambiente Tumoral
5.
RSC Adv ; 11(33): 20519-20528, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35479925

RESUMO

Breath analytics is currently being explored for the development of point-of-care devices in non-invasive disease detection. It is based on the measurement of volatile organic compounds (VOCs) and gases that are produced by the body because of the metabolic pathways. The levels of these metabolites vary due to alteration in the endogenous oxidative stress-related metabolic pathways and can be correlated to understand the underlying disease condition. The levels of exhaled hydrocarbons in human breath can be used to design a rapid, easy to use method for lung cancer detection. This work outlines the development of an electrochemical sensing platform that can be used for the non-invasive diagnosis of lung cancer by monitoring isopentane levels in breath. This electrochemical sensor platform involves the use of [BMIM]BF4@ZIF-8 for sensing the target analyte. This synthesized nanocomposite offers advantages for gas sensing applications as it possesses unique properties such as an electrochemically active Room Temperature Ionic Liquid (RTIL) and a crosslinking Metal Organic Framework (MOF) that provides increased surface area for gas absorption. This is the first report of a hydrocarbon-based sensor platform developed for lung cancer diagnosis. The developed sensor platform displays sensitivity and specificity for the detection of isopentane up to 600 parts-per-billion. We performed structural and morphological characterization of the synthesized nanocomposite using various analytical techniques such as PXRD, FESEM, FTIR, and DLS. We further analyzed the electrochemical activity of the synthesized nanocomposite using a standard glassy carbon electrode. The application of the nanocomposite for isopentane sensing was done using a commercially available carbon screen printed electrode. The results so obtained helped in strengthening our hypothesis and serve as a proof-of-concept for the development of a breathomics-enabled electrochemical strategy. We illustrated the specificity of the developed nanocomposite by cross-reactivity studies. We envision that the detection platform will allow sensitive and specific sensing of isopentane levels such that it can used for point of care applications in noninvasive and early diagnosis of lung cancer, thereby leading to its early treatment and decrease in mortality rate.

6.
Micromachines (Basel) ; 11(3)2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32213807

RESUMO

C-reactive protein (CRP) is considered to be an important biomarker associated with many diseases. During any physiological inflammation, the level of CRP reaches its peak at 48 h, whereas its half-life is around 19 h. Hence, the detection of low-level CRP is an important task for the prognostic management of diseases like cancer, stress, metabolic disorders, cardiovascular diseases, and so on. There are various techniques available in the market to detect low-level CRP like ELISA, Western blot, etc. An electrochemical biosensor is one of the important miniaturized platforms which provides sensitivity along with ease of operation. The most important element of an electrochemical biosensor platform is the electrode which, upon functionalization with a probe, captures the selective antibody-antigen interaction and produces a digital signal in the form of potential/current. Optimization of the electrode design can increase the sensitivity of the sensor by 5-10-fold. Herein, we come up with a new sensor design called the spiral electrochemical notification coupled electrode (SENCE) where the working electrode (WE) is concentric in nature, which shows better response than the market-available standard screen-printed electrode. The sensor is thoroughly characterized using a standard Ferro/Ferri couple. The sensing performance of the fabricated platform is also characterized by the detection of standard H2O2 using a diffusion-driven technique, and a low detection limit of 15 µM was achieved. Furthermore, we utilized the platform to detect a low level (100 ng/mL) of CRP in synthetic sweat. The manuscript provides emphasis on the design of a sensor that can offer good sensitivity in electrochemical biosensing applications.

7.
Proc Natl Acad Sci U S A ; 117(11): 6189-6195, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123116

RESUMO

Neurofibromatosis 1 (NF1) is caused by mutations in the NF1 gene, which encodes the protein, neurofibromin, an inhibitor of Ras activity. Cortical GABAergic interneurons (CINs) are implicated in NF1 pathology, but the cellular and molecular changes to CINs are unknown. We deleted mouse Nf1 from the medial ganglionic eminence, which gives rise to both oligodendrocytes and CINs that express somatostatin and parvalbumin. Nf1 loss led to a persistence of immature oligodendrocytes that prevented later-generated oligodendrocytes from occupying the cortex. Moreover, molecular and cellular properties of parvalbumin (PV)-positive CINs were altered by the loss of Nf1, without changes in somatostatin (SST)-positive CINs. We discovered that loss of Nf1 results in a dose-dependent decrease in Lhx6 expression, the transcription factor necessary to establish SST+ and PV+ CINs, which was rescued by the MEK inhibitor SL327, revealing a mechanism whereby a neurofibromin/Ras/MEK pathway regulates a critical CIN developmental milestone.


Assuntos
Córtex Cerebral/patologia , Neurônios GABAérgicos/patologia , Interneurônios/patologia , Proteínas com Homeodomínio LIM/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurofibromatose 1/patologia , Neurofibromina 1/genética , Fatores de Transcrição/metabolismo , Aminoacetonitrila/administração & dosagem , Aminoacetonitrila/análogos & derivados , Animais , Células Cultivadas , Córtex Cerebral/citologia , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Neurônios GABAérgicos/metabolismo , Humanos , Interneurônios/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Eminência Mediana/citologia , Camundongos , Camundongos Knockout , Neurofibromatose 1/genética , Neurofibromina 1/metabolismo , Neuroglia/citologia , Parvalbuminas/metabolismo , Cultura Primária de Células , Somatostatina/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo
8.
Cell Rep ; 26(5): 1157-1173.e5, 2019 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-30699346

RESUMO

Mafb and c-Maf transcription factor (TF) expression is enriched in medial ganglionic eminence (MGE) lineages, beginning in late-secondary progenitors and continuing into mature parvalbumin (PV+) and somatostatin (SST+) interneurons. However, the functions of Maf TFs in MGE development remain to be elucidated. Herein, Mafb and c-Maf were conditionally deleted, alone and together, in the MGE and its lineages. Analyses of Maf mutant mice revealed redundant functions of Mafb and c-Maf in secondary MGE progenitors, where they repress the generation of SST+ cortical and hippocampal interneurons. By contrast, Mafb and c-Maf have distinct roles in postnatal cortical interneuron (CIN) morphological maturation, synaptogenesis, and cortical circuit integration. Thus, Mafb and c-Maf have redundant and opposing functions at different steps in CIN development.


Assuntos
Linhagem da Célula , Córtex Cerebral/metabolismo , Interneurônios/metabolismo , Fator de Transcrição MafB/metabolismo , Proteínas Proto-Oncogênicas c-maf/metabolismo , Potenciais de Ação , Animais , Animais Recém-Nascidos , Apoptose , Membrana Celular/metabolismo , Movimento Celular , Proliferação de Células , Hipocampo/metabolismo , Eminência Mediana/metabolismo , Camundongos Knockout , Neuritos/metabolismo , Neurogênese , Parvalbuminas/metabolismo , Somatostatina/metabolismo , Sinapses/metabolismo
9.
ACS Omega ; 3(8): 9872-9879, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459115

RESUMO

Clean energy is the main requirement for human life. Redox flow battery may be an alternative to fossil fuels. An ion-exchange membrane is the heart of the redox flow battery. In the present study, we synthesize semi-interpenetrating cross-linked copolymer amphoteric ion-exchange membranes (AIEMs) with a partially rigid backbone. The styrene sulfonate and vinyl benzyl chloride monomers are used as the cationic and anionic moieties into the AIEMs. Three different types of quaternizing agents are used to convert a primary amine into a quaternary amine group. Here, we avoid the use of the carcinogenic chemical CMME, commonly used for the synthesis of anion-exchange membranes. The prepared membranes exhibit good electrochemical and physicochemical properties with a high acidic stability. The membranes also show moderate water uptake and dimensional change. The ZWMO membrane shows better properties among the AIEMs, with an ionic conductivity of 3.12 × 10-2 S cm-1 and 5.49 water molecules per functional group. The anion and cation-exchange capacities of the ZWMO membranes are calculated to be 1.11 and 0.62 mequiv/g. All AIEMs show good thermal and mechanical stabilities, calculated by differential scanning calorimetry, dynamic mechanical analysis, and universal testing machine analysis. The membranes show low vanadium ion permeability than the commercial membrane Nafion for their use in vanadium redox flow batteries. Further, the AIEMs are applied in redox flow batteries as separators and deliver good results with the charging and discharging phenomena, with 87% voltage efficiency and 91% current efficiency.

10.
Cereb Cortex ; 28(11): 3868-3879, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29028946

RESUMO

Human mutations in CNTNAP2 are associated with an array of neuropsychiatric and neurological syndromes, including speech and language disorders, epilepsy, and autism spectrum disorder (ASD). We examined Cntnap2's expression and function in GABAergic cortical interneurons (CINs), where its RNA is present at highest levels in chandelier neurons, PV+ neurons and VIP+ neurons. In vivo functions were studied using both constitutive Cntnap2 null mice and a transplantation assay, the latter to assess cell autonomous phenotypes of medial ganglionic eminence (MGE)-derived CINs. We found that Cntnap2 constitutive null mutants had normal numbers of MGE-derived CINs, but had reduced PV+ CINs. Transplantation assays showed that Cntnap2 cell autonomously regulated the physiology of parvalbumin (PV)+, fast-spiking CINs; no phenotypes were observed in somatostatin+, regular spiking, CINs. We also tested the effects of 4 human CNTNAP2 ASD missense mutations in vivo, and found that they impaired PV+ CIN development. Together, these data reveal that reduced CNTNAP2 function impairs PV+ CINs, a cell type with important roles in regulating cortical circuits.


Assuntos
Neurônios GABAérgicos/fisiologia , Interneurônios/fisiologia , Proteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Alelos , Animais , Transtorno do Espectro Autista , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Parvalbuminas/metabolismo , Proteína Reelina , Serina Endopeptidases/metabolismo , Córtex Somatossensorial/fisiologia , Telencéfalo/crescimento & desenvolvimento
11.
J Mater Chem B ; 4(48): 7888-7894, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263779

RESUMO

A benzoxazinone based fluorescent probe for the specific and efficient detection of bisulfite ions in aqueous medium is described. The probe formed a bisulfite/sulphite adduct with an associated turn-on fluorescence response in the red wavelength region. No interference was observed in the detection process from all possible competing anions and molecules, including cyanide ion, cysteine, homocysteine and glutathione. In addition, the probe showed a fast response time, low detection limit, and cell membrane permeability. Furthermore, the probe was two-photon excitable, enabling imaging of endogenous bisulfite ions in HeLa cells as well as in deep tissues from different organs of mouse.

12.
Aging Cell ; 2(4): 223-31, 2003 08.
Artigo em Inglês | MEDLINE | ID: mdl-12934716

RESUMO

The transcription of manganese superoxide dismutase (MnSOD), expression of which is essential for detoxification of superoxide radicals from mitochondria, has been shown to be regulated in vitro by many factors and conditions including oxidative stress, cytokines, lipopolysaccharide, cytoplasmic myc (c-myc), p53 and tumour necrosis factors. Here we describe genomic regions in Drosophila melanogaster with regulatory effects on transcription of the MnSOD gene at an organism-wide level. To understand the integrated regulation of MnSOD expression we screened chromosomes of D. melanogaster to locate deficiencies that altered the expression of MnSOD. Suppressors of MnSOD were screened by assessing the relative message abundance of MnSOD in 149 deletions covering approximately 81% of the Drosophila genome. The chromosomal deficiency Df(2R)017 significantly up-regulated MnSOD mRNA by 1.7-fold. Deficiency in four other genomic intervals, Df(1)ct-J4, Df(2L)BSC4, Df(3L)66C-G28 and Df(3R)Scr, down-regulated MnSOD expression. Changes in MnSOD expression were positively associated with paraquat sensitivity of the deletion genotypes. Thus, at least one candidate enhancer and four candidate suppressors exist in the Drosophila genome to regulate the transcriptional activity of the MnSOD gene in vivo.


Assuntos
Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Regulação Enzimológica da Expressão Gênica/genética , Genoma , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Animais , Regulação para Baixo/genética , Tolerância a Medicamentos/genética , Radicais Livres/metabolismo , Deleção de Genes , Genes Reguladores/genética , Mutação/genética , Paraquat/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Transcrição Gênica/genética , Regulação para Cima/genética
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