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1.
Nanotechnology ; 30(49): 495205, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31476745

RESUMO

Hybrid semiconductor nanostructures have attracted tremendous response due to their unique properties and applications in nano-optoelectronics and sensors. Here, we fabricated a back-gated transistor based on 300 nm channel of the Azurin-TiO2 hybrid nanostructure, whose enhanced performance is attributed to the synergetic effect of the metal oxide and azurin. Surface potential mapping under the dark and light condition using Kelvin probe force microscopy, gives the perfect correlation of band gap estimation for Azurin, TiO2 and Azurin-TiO2 nanostructures. The extracted parameters of the transistor exhibit the majority carrier mobility of 2.26 cm2 V-1 s-1, Schottky barrier height of 133.56 meV and low off current (6 × 10-10 A). The photodetector showed the high spectral response of 8.7 × 105 A W-1 and detectivity of 6.4 × 1014 Jones for 260 nm wavelength, at an applied gate bias of 5 V. The short carrier transit time (3 µs) and large recombination time (0.4 s) with multiple recirculations of photo generated carries facilitate the high gain of 2.6 × 106. A significant rejection ratio (R 260/R 530) of 56.2 at V GS = 5 V and the linear dynamic range of 45.75 dB for 260 nm wavelength is achieved. The obtained rise and fall time of the photodetector is 0.52 s, and 0.65 s, respectively. This study suggests the applicability of Azurin-TiO2 hybrid nanostructures with high performance for the biocompatible optoelectronic devices.

2.
Mater Sci Eng C Mater Biol Appl ; 104: 109881, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499940

RESUMO

Thymoquinone (TQ) loaded monodispersed mesoporous silica nanoparticles (TQ-MSNPs) with size of 188 ±â€¯3 nm were prepared and characterized using DLS, TEM and FTIR. These TQ-MSNPs overcome the limitations of free TQ like hydrophobicity, low aqueous and photo stability and thus enhance its anticancer activity. In vitro release kinetics showed biphasic drug release where up to 50% was released in first 8 h and subsequently 98% released after 48 h. Enhanced cytotoxicity of TQ-MSNPs was observed against MCF-7 and HeLa cell lines as compared to free TQ. DAPI and Annexin V-FITC/PI staining confirmed the induction of apoptosis in cancer cells following treatment with TQ-MSNPs. Also, TQ-MSNPs exhibited enhanced anti-invasion properties against both cell lines as very low concentration of loaded TQ imparts similar benefits as free TQ. Both TQ and TQ-MSNPs exerted their cytotoxicity via reactive oxygen species (ROS) generation, as addition of an antioxidant NAC attenuated their killing activity.

3.
Genes Dev ; 33(17-18): 1236-1251, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416966

RESUMO

Tumors display increased uptake and processing of nutrients to fulfill the demands of rapidly proliferating cancer cells. Seminal studies have shown that the proto-oncogene MYC promotes metabolic reprogramming by altering glutamine uptake and metabolism in cancer cells. How MYC regulates the metabolism of other amino acids in cancer is not fully understood. Using high-performance liquid chromatography (HPLC)-tandem mass spectrometry (LC-MS/MS), we found that MYC increased intracellular levels of tryptophan and tryptophan metabolites in the kynurenine pathway. MYC induced the expression of the tryptophan transporters SLC7A5 and SLC1A5 and the enzyme arylformamidase (AFMID), involved in the conversion of tryptophan into kynurenine. SLC7A5, SLC1A5, and AFMID were elevated in colon cancer cells and tissues, and kynurenine was significantly greater in tumor samples than in the respective adjacent normal tissue from patients with colon cancer. Compared with normal human colonic epithelial cells, colon cancer cells were more sensitive to the depletion of tryptophan. Blocking enzymes in the kynurenine pathway caused preferential death of established colon cancer cells and transformed colonic organoids. We found that only kynurenine and no other tryptophan metabolite promotes the nuclear translocation of the transcription factor aryl hydrocarbon receptor (AHR). Blocking the interaction between AHR and kynurenine with CH223191 reduced the proliferation of colon cancer cells. Therefore, we propose that limiting cellular kynurenine or its downstream targets could present a new strategy to reduce the proliferation of MYC-dependent cancer cells.


Assuntos
Neoplasias do Colo/fisiopatologia , Cinurenina/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Triptofano/metabolismo , Sistema ASC de Transporte de Aminoácidos/genética , Antineoplásicos/farmacologia , Arilformamidase/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Indóis/farmacologia , Cinurenina/genética , Transportador 1 de Aminoácidos Neutros Grandes/genética , Antígenos de Histocompatibilidade Menor/genética , Oximas/farmacologia , Sulfonamidas/farmacologia
4.
iScience ; 19: 83-92, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31357170

RESUMO

Fine-tuning of transcriptional responses can be critical for long-term outcomes in response to an environmental challenge. The circadian protein Nocturnin belongs to a family of proteins that include exonucleases, endonucleases, and phosphatases and is most closely related to the CCR4 family of deadenylases that regulate the cellular transcriptome via control of poly(A) tail length of RNA transcripts. In this study, we investigate the role of Nocturnin in regulating the transcriptional response and downstream metabolic adaptations during cold exposure in brown adipose tissue. We find that Nocturnin exhibits dual localization within the cytosol and mitochondria, and loss of Nocturnin causes changes in expression of networks of mRNAs involved in mitochondrial function. Furthermore, Nocturnin-/- animals display significantly elevated levels of tricarboxylic acid cycle intermediates, indicating that they have distinct metabolic adaptations during a prolonged cold exposure. We conclude that cold-induced stimulation of Nocturnin levels can regulate long-term metabolic adaptations to environmental challenges.

5.
Curr Genet ; 65(6): 1325-1332, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31119371

RESUMO

Centromere identity is specified epigenetically by specialized nucleosomes containing the evolutionarily conserved centromeric histone H3 variant (Cse4 in budding yeast, CENP-A in humans) which is essential for faithful chromosome segregation. However, the mechanisms of epigenetic regulation of Cse4 have not been clearly defined. We have identified two kinases, Cdc5 (Plk1 in humans) and Ipl1 (Aurora B kinase in humans) that phosphorylate Cse4 to prevent chromosomal instability (CIN). Cdc5 associates with Cse4 in mitosis and Cdc5-mediated phosphorylation of Cse4 is coincident with the centromeric enrichment of Cdc5 during metaphase. Defects in Cdc5-mediated Cse4 phosphorylation causes CIN, whereas constitutive association of Cdc5 with Cse4 results in lethality. Cse4 is also a substrate for Ipl1 and phospho-mimetic cse4 mutants suppress growth defects of ipl1 and Ipl1 kinetochore substrate mutants, namely dam1 spc34 and ndc80. Ipl1-mediated phosphorylation of Cse4 regulates kinetochore-microtubule interactions and chromosome biorientation. We propose that collaboration of Cdc5- and Ipl1-mediated phosphorylation of Cse4 modulates kinetochore structure and function, and chromosome biorientation. These findings demonstrate how phosphorylation of Cse4 regulates the integrity of the kinetochore, and acts as an epigenetic marker for mitotic control.

6.
Medicine (Baltimore) ; 98(20): e15668, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31096497

RESUMO

INTRODUCTION: Intravascular migration of a double J stent into the inferior vena cava is an uncommon complication. The management of such complication is less reported in the literature. This study aimed to reveal the diagnosis and treatment process of migration of a double J stent into the inferior vena cava. PATIENT CONCERNS: A 53-year-old male patients was transferred to our hospital because of migration of a double J stent into the inferior vena cava after left-side pyelolithotomy. DIAGNOSIS: In accordance with manifestations on computed tomography urography, the patient was diagnosed with migration of a double J stent into the inferior vena cava. INTERVENTIONS: Percutaneous nephroscope under C-arm guidance was performed to remove the migrated stent. After the operation, the patient was treated with continued anticoagulants and antibiotics. OUTCOMES: The migrated stent was removed successfully without any complications, and a new double J stent was placed and its location was confirmed under C-arm. The patient was discharged in good condition and the follow-up was uneventful. CONCLUSION: Intravascular migration of a double J stent into the inferior vena cava is an uncommon complication. Radiologic imaging after placement of ureteral stent is critical for prevention of this complication. Percutaneous nephroscope under C-arm guidance is a safe and effective approach to remove the migrated DJS in the IVC.


Assuntos
Migração de Corpo Estranho/cirurgia , Stents , Veia Cava Inferior/cirurgia , Antibacterianos/uso terapêutico , Anticoagulantes/uso terapêutico , Migração de Corpo Estranho/diagnóstico por imagem , Humanos , Cálculos Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Veia Cava Inferior/diagnóstico por imagem
7.
Biosens Bioelectron ; 136: 23-30, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31029006

RESUMO

In this study, we report a facile, reusable, and highly sensitive label-free impedance sensor for discriminating Gram-positive and Gram-negative bacteria. The impedance sensor was fabricated using gold interdigitated electrodes onto a tungsten oxide thin film. X-Ray diffraction confirmed the formation of polycrystalline tungsten oxide. Field emission scanning electron microscopy and atomic force microscopy revealed that tungsten oxide has a porous structure. Tungsten oxide was functionalized with vancomycin, a glycopeptide antibiotic known to have a specific interaction with the peptidoglycan layer of Gram-positive bacteria. Fourier transform infrared microscopy and scanning electron microscopy were employed to test the morphological coating of vancomycin on interdigitated electrodes/tungsten oxide sensor. The functionalized tungsten oxide sensor was highly efficient in the capture of Gram-positive bacteria. The impedance measurement was also sensitive to differentiate between viable and non-viable Gram-positive bacteria. Limit of detection 102 colony forming unit/ml, linear dynamic range 102-107 colony forming unit/ml under physiological conditions and reusable nature of this vancomycin coated impedance sensor provide a label-free strategy for quick, sensitive and highly selective detection of Gram-positive bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Positivas/isolamento & purificação , Vancomicina/farmacologia , Impedância Elétrica , Eletrodos , Bactérias Gram-Negativas/classificação , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/citologia , Bactérias Gram-Positivas/efeitos dos fármacos , Viabilidade Microbiana , Microscopia de Força Atômica , Óxidos , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier , Tungstênio
8.
Int J Surg Case Rep ; 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30948268

RESUMO

INTRODUCTION: Partial anomalous pulmonary venous connection (PAPVC) is a rare entity. Only 10% of these are left sided. An intact atrial septum is further uncommon. PRESENTATION OF CASE: We present a case of left sided PAPVC with no atrial septal defect (ASD), who presented with effort intolerance and an unremarkable physical examination. Computed tomography pulmonary angiography (CTPA) confirmed the primary diagnosis as suggested by an initial 2-D echocardiography, and aided in better understanding of the anatomy. CONCLUSION: Patient underwent successful surgery through a simple & reproducible technique of anastomosis of vertical vein to left atrial appendage. Patient recovered uneventfully and was discharged on day 10.

9.
Cell Metab ; 29(6): 1291-1305.e8, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31006591

RESUMO

The hepatic TCA cycle supports oxidative and biosynthetic metabolism. This dual responsibility requires anaplerotic pathways, such as pyruvate carboxylase (PC), to generate TCA cycle intermediates necessary for biosynthesis without disrupting oxidative metabolism. Liver-specific PC knockout (LPCKO) mice were created to test the role of anaplerotic flux in liver metabolism. LPCKO mice have impaired hepatic anaplerosis, diminution of TCA cycle intermediates, suppressed gluconeogenesis, reduced TCA cycle flux, and a compensatory increase in ketogenesis and renal gluconeogenesis. Loss of PC depleted aspartate and compromised urea cycle function, causing elevated urea cycle intermediates and hyperammonemia. Loss of PC prevented diet-induced hyperglycemia and insulin resistance but depleted NADPH and glutathione, which exacerbated oxidative stress and correlated with elevated liver inflammation. Thus, despite catalyzing the synthesis of intermediates also produced by other anaplerotic pathways, PC is specifically necessary for maintaining oxidation, biosynthesis, and pathways distal to the TCA cycle, such as antioxidant defenses.

10.
Cell Rep ; 26(13): 3709-3725.e7, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917323

RESUMO

Mitochondrial Ca2+ uniporter (MCU)-mediated Ca2+ uptake promotes the buildup of reducing equivalents that fuel oxidative phosphorylation for cellular metabolism. Although MCU modulates mitochondrial bioenergetics, its function in energy homeostasis in vivo remains elusive. Here we demonstrate that deletion of the Mcu gene in mouse liver (MCUΔhep) and in Danio rerio by CRISPR/Cas9 inhibits mitochondrial Ca2+ (mCa2+) uptake, delays cytosolic Ca2+ (cCa2+) clearance, reduces oxidative phosphorylation, and leads to increased lipid accumulation. Elevated hepatic lipids in MCUΔhep were a direct result of extramitochondrial Ca2+-dependent protein phosphatase-4 (PP4) activity, which dephosphorylates AMPK. Loss of AMPK recapitulates hepatic lipid accumulation without changes in MCU-mediated Ca2+ uptake. Furthermore, reconstitution of active AMPK, or PP4 knockdown, enhances lipid clearance in MCUΔhep hepatocytes. Conversely, gain-of-function MCU promotes rapid mCa2+ uptake, decreases PP4 levels, and reduces hepatic lipid accumulation. Thus, our work uncovers an MCU/PP4/AMPK molecular cascade that links Ca2+ dynamics to hepatic lipid metabolism.

11.
Indian J Dent Res ; 30(1): 10-14, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900649

RESUMO

Introduction: Tobacco use is one of the major preventable causes of death and disability worldwide. The practice of law can be demanding and exceedingly stressful. Trends in tobacco use among young people are important to document because these findings will help inform the development of appropriate preventive intervention programs for youth. Aim: To assess prevalence of tobacco and associated risk factors among university law students in Indore city. Objective: To identify the strength of association related to tobacco consumption. Materials and Methods: A descriptive cross-sectional study was conducted among 278 law students in Indore city using convenient sampling technique. The data was collected using pre-tested close ended self-administered questionnaire. Frequency distribution analysis was performed. Bivariate analysis was done followed by logistic regression analysis. The level of significance for all the tests was set at P < 0.05. Results: The present study revealed that 32% of the study subjects consumed smoking tobacco as compared to 2.5% of smokeless tobacco. Nearly two-third of the law students consumed tobacco at public places 185 (66.5%) under the influence of friends. Only 18 (6.5%) study subjects tried to quit tobacco in the last 12 months whereas 65 (23.4%) of them never wanted to quit the habit of tobacco consumption. A bivariate analysis was performed to identify the risk factors related to tobacco consumption. It was found that male individuals (OR=2.04, P =0.004*) whose family members had the habit of tobacco consumption (OR=2.9, P =0.002*) were at a higher risk for consuming tobacco. The factors that became significant in bivariate analysis were then entered in logistic regression analysis [Enter method] to identify the strength of association. The individuals who had the habit of tobacco consumption among family members emerged as the strongest risk predictor leading to tobacco consumption amongst the students. Conclusion: The present study revealed that smoking form of tobacco consumption (cigarette- 32%) was more prevalent among the male study subjects under the influence of friends and with family members who had the habit of consuming tobacco at their place of residence.


Assuntos
Jurisprudência , Estudantes/estatística & dados numéricos , Fumar Tabaco/epidemiologia , Universidades/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Família , Feminino , Amigos , Humanos , Índia/epidemiologia , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
12.
Mol Biol Cell ; 30(8): 1020-1036, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30726152

RESUMO

Evolutionarily conserved polo-like kinase, Cdc5 (Plk1 in humans), associates with kinetochores during mitosis; however, the role of cell cycle-dependent centromeric ( CEN) association of Cdc5 and its substrates that exclusively localize to the kinetochore have not been characterized. Here we report that evolutionarily conserved CEN histone H3 variant, Cse4 (CENP-A in humans), is a substrate of Cdc5, and that the cell cycle-regulated association of Cse4 with Cdc5 is required for cell growth. Cdc5 contributes to Cse4 phosphorylation in vivo and interacts with Cse4 in mitotic cells. Mass spectrometry analysis of in vitro kinase assays showed that Cdc5 phosphorylates nine serine residues clustered within the N-terminus of Cse4. Strains with cse4-9SA exhibit increased errors in chromosome segregation, reduced levels of CEN-associated Mif2 and Mcd1/Scc1 when combined with a deletion of MCM21. Moreover, the loss of Cdc5 from the CEN chromatin contributes to defects in kinetochore integrity and reduction in CEN-associated Cse4. The cell cycle-regulated association of Cdc5 with Cse4 is essential for cell viability as constitutive association of Cdc5 with Cse4 at the kinetochore leads to growth defects. In summary, our results have defined a role for Cdc5-mediated Cse4 phosphorylation in faithful chromosome segregation.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Segregação de Cromossomos/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces/metabolismo , Proteínas de Ciclo Celular/fisiologia , Centrômero/metabolismo , Proteína Centromérica A/fisiologia , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histonas/metabolismo , Cinetocoros/metabolismo , Mitose , Proteínas Nucleares/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/fisiologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomycetales/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo
13.
Proc Natl Acad Sci U S A ; 116(9): 3662-3667, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808755

RESUMO

Kaufman oculocerebrofacial syndrome (KOS) is a recessive neurodevelopmental disorder characterized by intellectual disability and lack of speech. KOS is caused by inactivating mutations in UBE3B, but the underlying biological mechanisms are completely unknown. We found that loss of Ube3b in mice resulted in growth retardation, decreased grip strength, and loss of vocalization. The brains of Ube3b -/- mice had hypoplasia of the corpus callosum, enlarged ventricles, and decreased thickness of the somatosensory cortex. Ube3b -/- cortical neurons had abnormal dendritic morphology and synapses. We identified 22 UBE3B interactors and found that branched-chain α-ketoacid dehydrogenase kinase (BCKDK) is an in vivo UBE3B substrate. Since BCKDK targets several metabolic pathways, we profiled plasma and cortical metabolomes from Ube3b -/- mice. Nucleotide metabolism and the tricarboxylic acid cycle were among the pathways perturbed. Substrate-induced mitochondrial respiration was reduced in skeletal muscle but not in liver of Ube3b -/- mice. To assess the relevance of these findings to humans, we identified three KOS patients who had compound heterozygous UBE3B mutations. We discovered changes in metabolites from similar pathways in plasma from these patients. Collectively, our results implicate a disease mechanism in KOS, suggest that it is a metabolic encephalomyopathy, and provide an entry to targeted therapies.


Assuntos
Anormalidades do Olho/genética , Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Deformidades Congênitas dos Membros/genética , Microcefalia/genética , Proteínas Quinases/genética , Ubiquitina-Proteína Ligases/genética , Adolescente , Adulto , Animais , Encéfalo/fisiopatologia , Criança , Anormalidades do Olho/fisiopatologia , Facies , Humanos , Deficiência Intelectual/fisiopatologia , Transtornos do Desenvolvimento da Linguagem/fisiopatologia , Deformidades Congênitas dos Membros/fisiopatologia , Masculino , Redes e Vias Metabólicas , Camundongos , Camundongos Knockout , Microcefalia/fisiopatologia , Mutação , Fenótipo , Ubiquitina/genética
14.
Elife ; 82019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30735131

RESUMO

Although numerous long noncoding RNAs (lncRNAs) have been identified, our understanding of their roles in mammalian physiology remains limited. Here, we investigated the physiologic function of the conserved lncRNA Norad in vivo. Deletion of Norad in mice results in genomic instability and mitochondrial dysfunction, leading to a dramatic multi-system degenerative phenotype resembling premature aging. Loss of tissue homeostasis in Norad-deficient animals is attributable to augmented activity of PUMILIO proteins, which act as post-transcriptional repressors of target mRNAs to which they bind. Norad is the preferred RNA target of PUMILIO2 (PUM2) in mouse tissues and, upon loss of Norad, PUM2 hyperactively represses key genes required for mitosis and mitochondrial function. Accordingly, enforced Pum2 expression fully phenocopies Norad deletion, resulting in rapid-onset aging-associated phenotypes. These findings provide new insights and open new lines of investigation into the roles of noncoding RNAs and RNA binding proteins in normal physiology and aging.

15.
Front Microbiol ; 9: 2703, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30483230

RESUMO

The rice bacterial blight pathogen Xanthomonas oryzae pv. oryzae (Xoo) injects transcription activator-like effectors (TALEs) that bind and activate host "susceptibility" (S) genes important for disease. Clade III SWEET genes are major S genes for bacterial blight. The resistance genes xa5, which reduces TALE activity generally, and xa13, a SWEET11 allele not recognized by the cognate TALE, have been effectively deployed. However, strains that defeat both resistance genes individually were recently reported in India and Thailand. To gain insight into the mechanism(s), we completely sequenced the genome of one such strain from each country and examined the encoded TALEs. Strikingly, the two strains are clones, sharing nearly identical TALE repertoires, including a TALE known to activate SWEET11 strongly enough to be effective even when diminished by xa5. We next investigated SWEET gene induction by the Indian strain. The Indian strain induced no clade III SWEET in plants harboring xa13, indicating a pathogen adaptation that relieves dependence on these genes for susceptibility. The findings open a door to mechanistic understanding of the role SWEET genes play in susceptibility and illustrate the importance of complete genome sequence-based monitoring of Xoo populations in developing varieties with effective disease resistance.

16.
Biosens Bioelectron ; 126: 478-484, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30472445

RESUMO

The in-situ and rapid detection of live and dead bacteria is essential for human and environmental care. It has become one of the biggest needs in the biological and medical sciences to prevent infectious diseases, which usually occur in hospitals and field clinics. In the current scenario, antibiotic resistance is one of the severe public health problems, which requires a quick and efficient solution. Here, we report a facile sensitive, portable, user-friendly, cost-effective and time saving approach for detection of live, dead and drug-resistant bacteria. The endogenous H2S evolution was targeted to differentiate between live and dead as well as antibiotic resistant bacteria. The silver nanorods (AgNRs) arrays sensors were fabricated by glancing angle deposition technique. The colorimetric and water wettability features of as-synthesized AgNRs are found to be highly sensitive and selective for H2S. E. coli. P. aeruginosa, B. subtilis and S. aureus were used as a model organism in this study. All the bacteria were found to produce H2S by their metabolism process. In order to detect the antibiotic resistant E. coli were grown in the presence of different concentration of ampicillin in Luria broth. A drastic visible change in color as well as wetting of AgNRs array was observed. To make the technique easy, a user-friendly and field deployable mobile app 'Colorimetric Detector' was developed. This technique takes only 4-6 h whereas the conventional methods need around 24 h for the same. This dual mode facile and, inexpensive method can be easily scaled up in the field of diagnostics.

17.
Chemosphere ; 217: 483-495, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30439660

RESUMO

An aero-gel based solid solution of titanium and cerium oxide nanoparticles have been used for the first time for ultra fast and trace level removal of arsenic from water. The interconnected long range ordered mesoporous structure was observed from TEM analysis which has been verified as an essential facet for the fast removal of arsenic in this study. The HR-XRD spectra indicated the face centred cubic structure with Fm3¯m space group. Le-Bail refinement and Raman spectroscopy confirmed the formation of single phase solid solution of Ce1-XTixO2-Y oxide nanoparticles. The HR-XPS and FT-IR study indicated the surface complexation and partial oxidation of As(III) to As(V) via electron transfer mechanism by reduction of Ce(IV) to Ce(III) and Ti(IV) to Ti(III) simultaneously during adsorption process. The kinetics study demonstrated 99% removal of As(III) within 10 min of initiating the adsorption process. The effect of pH and interfering ions confirmed the wide range of applicability for solid solution of titania and cerium oxide nanoparticles over the different environmental conditions for the removal of arsenic. The adsorption capacity for our best adsorbent (Ce0.8Ti0.2O2-y) was found to be 2 × 105 mg kg-1 while the lowest concentration of water body system was 7 µg L-1 which is the minimum concentration of arsenic achieved by any metal oxide based adsorbent.

18.
Cell Rep ; 25(8): 2223-2233.e6, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30463017

RESUMO

Pathways underlying metabolic reprogramming in cancer remain incompletely understood. We identify the transmembrane serine protease TMPRSS11B as a gene that promotes transformation of immortalized human bronchial epithelial cells (HBECs). TMPRSS11B is upregulated in human lung squamous cell carcinomas (LSCCs), and high expression is associated with poor survival of non-small cell lung cancer patients. TMPRSS11B inhibition in human LSCCs reduces transformation and tumor growth. Given that TMPRSS11B harbors an extracellular (EC) protease domain, we hypothesized that catalysis of a membrane-bound substrate modulates tumor progression. Interrogation of a set of soluble receptors revealed that TMPRSS11B promotes solubilization of Basigin, an obligate chaperone of the lactate monocarboxylate transporter MCT4. Basigin release mediated by TMPRSS11B enhances lactate export and glycolytic metabolism, thereby promoting tumorigenesis. These findings establish an oncogenic role for TMPRSS11B and provide support for the development of therapies that target this enzyme at the surface of cancer cells.

19.
Mater Sci Eng C Mater Biol Appl ; 92: 673-684, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184794

RESUMO

Curcumin was employed to prepare anticancer nanoparticles (size 175 ±â€¯15 nm) using anti-inflammatory enzyme serratiopeptidase by desolvation method. Here serratiopeptidase acted as a carrier as well as bioactive molecule in the nanoformulations. The Cur-SPD NPs (curcumin loaded serratiopeptidase nanoparticles) were characterized using DLS, FESEM and FTIR. The in vitro release behavior depicted biphasic pattern at 37 °C (pH 7.4) and release of 95% of both molecules occurred in 24 h. Serratiopeptidase not only provided stability to curcumin but also increased its effectiveness against cancer cells. These nanoparticles had anti-cancer activity in MCF-7 and HeLa cell lines as shown by cytotoxicity assay, DAPI nuclear staining, ROS production and DNA damage. The immunomodulatory tests showed that Cur-SPD NPs reduce level of IL-6 but increase TNFα level in THP1 cell lines. Structural similarity of serratiopeptidase to matrix metallo proteases (MMPs), particularly MMP8, have been found (based on low RMSD values) to induce TNFα production and play tumour suppressive role in certain cancers. Thus anti-cancer properties of Cur-SPD NPs may be attributed to synergistic effect of curcumin and serratiopeptidase. Thus results in present investigation provide an insight on role of serratiopeptidase in development of co-delivery of multifunctional nanoparticles with anti-cancer properties introduction.

20.
Bioresour Technol ; 269: 121-126, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30157443

RESUMO

Acrylamide is a potent carcinogen and neurotoxin formed by the Maillard reaction when l-asparagine reacts with starch at high temperature. It is formed in food materials mainly deep fried and bakery products. Enzymatic pretreatment of these food products with asparaginase enzyme leads to reduction in acrylamide. However, enzymatic process is quite expensive due to high cost, low catalytic efficiency as well as problem with enzyme reusability. Present work deals with these problems by exploring l-asparaginase from Bacillus aryabhattai. Asparaginase enzyme was immobilized on APTES modified magnetic nanoparticles. It was found to be more than three-fold increase their thermal stability from free enzyme and retained 90% activity after fifth cycle. The immobilized enzyme also showed better affinity towards its substrate. During pretreatment of asparagine in a starch-asparagine food model system and it was clearly demonstrated that asparaginase nanoconjugates had reduced the formation of acrylamide by more than 90% within 30 min.


Assuntos
Acrilamida/química , Asparaginase/metabolismo , Nanopartículas de Magnetita , Asparagina , Reação de Maillard
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