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1.
Opt Lett ; 47(3): 489-492, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103662

RESUMO

The prevalent material design principles for optical thermometry primarily rely on thermally driven changes in the relative intensities of the thermally coupled levels (TCLs) of rare-earth-doped phosphor materials, where the maximum achievable sensitivity is limited by the energy gap between the TCLs. In this work, a new, to the best of our knowledge, approach to thermometric material design is proposed, which is based on temperature tuning of PL emission from the visible to the NIR region. We demonstrate a model ferroelectric phosphor, Eu3+-doped 0.94(Na1/2Bi1/2TiO3)-0.06(BaTiO3) (NBT-6BT), which, by virtue of the contrasting effects of temperature on PL signals from the host and Eu3+ intraband transitions, can achieve a relative thermal sensitivity as high as 3.05% K-1. This model system provides a promising alternative route for developing self-referencing optical thermometers with high thermal sensitivity and good signal discriminability.

2.
Cardiol Young ; 30(11): 1722-1727, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32856582

RESUMO

INTRODUCTION: Lifetech Konar-multifunctional occluder is a novel device which is primarily used for the closure of ventricular septal defects. Being "multifunctional", the occluder has the potential to be useful in various structural cardiac defects. MATERIALS AND METHODS: We share our retrospective review from two centres regarding non-conventional usage of multifunctional occluders in CHD. Eight patients who underwent interventions using multifunctional occluders for lesions other than ventricular septal defects between March 2019 to September 2019 were included in the study. The patients were analysed based on demography, the size and type of lesion, procedural success, and development of complications. All patients were followed up in the outpatient department for a minimum period of 6 months. RESULTS: The median age and weight of the cohort were 3.2 years and 9 kg, respectively. Six patients had patent ductus arteriosus, while one patient had aorto-pulmonary window and one had a coronary arterio-venous fistula. The sizing of the occluders and the procedural approach were based on the underlying pathology. The most commonly used occluder was 6 × 4 mm variant. One patient had successful implantation but had significant intra-device residual flow and was thus replaced by a different occluder. There were no major complications, nor any incidences of device embolisation or malposition. On follow-up, all patients had uneventful course. CONCLUSION: Konar-multifunctional occluder can be safely used in lesions other than ventricular septal defects, when needed under specific circumstances. Its unique characteristics make it a versatile choice in a variety of cardiac lesions.


Assuntos
Permeabilidade do Canal Arterial , Dispositivo para Oclusão Septal , Cateterismo Cardíaco , Permeabilidade do Canal Arterial/cirurgia , Humanos , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
3.
Physiol Mol Biol Plants ; 26(8): 1583-1598, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32801488

RESUMO

C4 species, Amaranthus viridis L. exhibited a significant bioaccumulation of aluminium (Al) through the duration of 3- and 5-days exposure. As compared to control, Amaranthus appeared as excess-accumulator with maximum 5.85-fold bioaccumulation of Al in root. Cellular responses to Al tolerance initially scored tissue specific distribution of metal through cortical layers revealed by electron microscopy. The affected cells changed an oxidative status as read by histochemical stains, particularly, for hydrogen peroxide. Osmotic stress and its stability were scored by maximum proline and free amino acids accumulation with 1.53 and 1.59-fold increase over control. The accumulation of phenolics and flavonoids were over expressed in the ranges of 2.48-2.50-fold and 2.00-1.5-fold at 3- and 5-days respectively against control. Anti-oxidation to detoxify Al stress was facilitated by variants of peroxidases. For exclusion mechanism of metal, esterase activity significantly over expressed with maximum value of 1.80-fold at 5-days. The polymorphism of esterase exhibited few significant over produced bands, varied in numbers as detected by densitometric scanning. Moreover, plant extract was satisfactorily potential under in vitro anti-oxidation systems through assay of 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), ferric chelation activity etc. Therefore, weeds like Amaranthus would be a bioprospecting in role likely involved in phytoremediation of metal.

4.
J Am Coll Nutr ; 38(5): 415-423, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30696389

RESUMO

Objective: Tea (Camellia sinensis Linn.; family: Theaceae) is popular as a stimulant beverage across the globe and is also utilized as a functional antioxidant in alternative medicine. This study has evaluated the impact of seasonal variation on phyto-constituents of tea. Method: The antiproliferative potential of methanolic extracts of tea leaves collected in the rainy season (MECR) was compared with the extract of tea leaves collected in the autumn season (MECA) of the same mother plant. Evaluation of in vivo antitumor activity was carried out in adult female Swiss albino mice groups inoculated with Ehrlich ascites carcinoma (EAC) cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to compare efficacy of MECR with that of MECA in the EAC cell line. Both qualitative and quantitative tests for phytochemical constituents present in MECA and MECR were performed. Antitumor efficacy of both the extracts was determined by evaluating different tumor markers showing dose-dependent cytotoxicity. Results: Statistically significant reduction in EAC-induced tumor was observed in MECR treated mice compared to MECA treated ones. Cell decimation was significantly higher with MECR treatment, where restoration of different parameters including tissue structures returned to normal. Moreover, gas chromatography-mass spectrometry (GC-MS) study revealed the presence of cyclobarbital and benzazulene derivative in MECR, which is thought to be a novel source of these chemicals. Conclusions: To our knowledge, there is no report that has attempted to reveal nutritional changes in terms of efficacy and variation in anticancer constituents in tea leaves, plucked in two seasons. This study revealed a novel source of barbital and benzazulene derivative. The unique presence of cyclobarbital and benzazulene, as revealed from GC-MS data, in methanolic extract of tea leaves collected during the rainy season (MECR) may have contributed to its enhanced in vitro (adopting MTT assay) and in vivo (on EAC-infected Swiss albino mice) cytotoxicity vis-à-vis antiproliferative properties compared to methanolic extract of tea leaves collected during the autumn season (MECA). The nature of plucking leaves in the two selected seasons is different.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Metanol/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Chá/química , Animais , Antineoplásicos Fitogênicos/química , Barbital/farmacologia , Camellia sinensis , Carcinoma de Ehrlich , Linhagem Celular Tumoral , Feminino , Metanol/química , Camundongos , Extratos Vegetais/química , Estações do Ano
5.
Mol Biol Rep ; 46(1): 59-66, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30350235

RESUMO

The present work highlights some preliminary observations on metabolism in rice (Oryza sativa Linn.) when an aquatic fern Azolla pinnata R.Br. was co-cultured under 2,4-Dichlorophenoxy acetic acid toxicity. We have observed the effects of Azolla in both fresh and dried forms. This work signifies the possible physiological changes of a crop plant by using Azolla as a bioremediator. In brief the herbicide 2,4-D is considered as stressor to rice plants and by applying the fresh and dried Azolla we investigate the changes occurred. The activities of different nitrogen metabolizing enzymes and reactive oxygen species were observed. On the other hand chlorophyll and carotenoids synthesis were retrieved by addition of fresh and dried Azolla mass over 2,4-D toxicity. Thus, the efficiency of fresh and dried Azolla mass was evaluated under herbicidal toxicity in rice. We evaluate the bio remediating role of Azolla plants against 2,4-D stress and conclude this species would also be supporting in supplementation of major nutrients to rice plants.


Assuntos
Ácido 2,4-Diclorofenoxiacético/metabolismo , Técnicas de Cocultura/métodos , Oryza/efeitos dos fármacos , Clorofila/metabolismo , Gleiquênias/metabolismo , Nitrogênio/metabolismo , Oryza/metabolismo , Oryza/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/efeitos dos fármacos
6.
Ecotoxicol Environ Saf ; 183: 109600, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31509927

RESUMO

Involvement of abscisic acid (ABA) was studied for aluminium (Al) sensitivity through functioning of sub1A quantitative trait loci in rice cultivars. sub1A quantitative trait loci bearing cv. Swarna Sub1 was found almost compatible with non sub1A quantitative trait loci bearing cv. Swarna for abscisic acid accumulation all through the aluminium concentrations. However, abscisic acid was self inductive by over expression of its biosynthetic gene in nine-cis-epoxycarotenoid dioxygenase 3 (NCED3) more in cv. Swarna than other. The effect of abscisic acid pretreatment was variable for specific leaf weight, leaf mass ratio and others for the cultivars. Bio-accumulation of aluminium had revealed the sensitivity of toxicity more in cv. Swarna than other. In connection to oxidative stress generation of reactive oxygen species was detected by both histochemical and in vitro assays through hematoxylin, Evans blue and schiff's reactions. Abscisic acid pretreatment had significantly reversed the effects of aluminium toxicity for reactive oxygen species generation. Regardless of varieties sensitivity of aluminium was more prone in shoot than root as detected by nitro blue tetrazolium and 3,3'-diaminobenzidine mediated signalling. Activity in metal chelation in extra cellular spaces monitored through esterase activity and that also established independence of abscisic acid pretreatment for cv. Swarna Sub1. The specific polymorphism of esterase at protein level strengthened the bio-monitoring of aluminium through the rice varieties as well its modulation with abscisic acid. Abscisic acid has been discussed an important effectors to modulate the tolerance pathway of rice cultivars through intrusion of sub1A quantitative trait loci.


Assuntos
Ácido Abscísico/metabolismo , Alumínio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/efeitos dos fármacos , Locos de Características Quantitativas , Oryza/genética , Oryza/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
Pharmacol Res ; 132: 188-203, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29229353

RESUMO

1,4-benzothiazines have ameliorative effects through inhibition of COX-2 mediated STAT-3 pathways at G-protein couple receptor site. As per this scenario, we recently prepared and tested novel 1,4-benzothiazine derivatives against HT-29 human colon cancer cell line. Two compounds namely AR13 and AR15 showed higher inhibitions among all the synthesized compounds. In the present context, we conducted the in vivo antiproliferative action and identified the molecular mechanism associated to cytotoxic action of AR13 and AR15 in dimethylhydrazine (DMH) induced colorectal carcinoma (CRC) model. Various physiological, oxidative stress, histopathology, ELISA, qRT-PCR, western blot and NMR-based metabolomics were accomplished to evaluate the anticancer effect of titled compounds. Both compounds were subjected to histological and biochemical tests to observe the protective action of the compounds. ELISA showed potential role of these compounds to normalize increased levels of IL-2, IL-6 and COX-2 mediators. This action was more pronounced for COX-2 rather than IL-2 and IL-6. Gene expression analyses further revealed that both of them attenuated the over-expressed COX-2 gene. Furthermore, it was confirmed that these compounds exerted antitumor potential via preventing COX-2 induced JAK-2 and STAT-3 phosphorylation. This action was substansiated by immunohistochemistry using JAK2, p-JAK2, STAT3 and p-STAT3 targets in colon tissue. Finally, score plots of PLS-DA models exhibited significant metabolic discriminations between the treated and CRC groups, and both compounds showed ability to restore the imbalance of multiple metabolites during CRC. In conclusion, our study provided the evidence towards better antiproliferative effect of AR13 and AR15 in DMH-induced CRC through the blockade of COX-2/JAK-2/STAT-3 signal transduction pathway and could be demonstrated as useful anti-CRC candidate molecules for future anticancer therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Janus Quinase 2/metabolismo , Fator de Transcrição STAT3/metabolismo , Tiazinas/farmacologia , Animais , Antineoplásicos/uso terapêutico , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/genética , Dimetilidrazinas , Janus Quinase 2/genética , Masculino , Ratos Wistar , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico , Tiazinas/uso terapêutico
8.
Inorg Chem ; 57(20): 12727-12739, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30281293

RESUMO

The toxicity of nanomaterials can sometimes be attributed to photogenerated reactive oxygen species (ROS), but these ROS can also be scavenged by nanomaterials, yielding opportunities for crossover between the properties. The morphology of nanomaterials also influences such features due to defect-induced properties. Here we report morphology-induced crossover between pro-oxidant activity (ROS generation) and antioxidant activity (ROS scavenging) of MgO. To study this process in detail, we prepared three different nanostructures of MgO (nanoparticles, nanoplates, and nanorods) and characterized them by HRTEM. These three nanostructures effectively generate superoxide anions (O2•-) and hydroxyl radicals (•OH) at higher concentrations (>500 µg/mL) but scavenge O2•- at lower concentrations (40 µg/mL) with successful crossover at 200 µg/mL. Nanorods of MgO generate the highest levels of O2•-, whereas nanoparticles scavenge O2•- to the highest extent (60%). Photoluminescence studies reveal that such crossover is based on the suppression of F2+ and the evolution of F+, F2+, and F23+ defect centers. The evolution of these defect centers reflects the antibacterial activity of MgO nanostructures which is initiated at 200 µg/mL against Gram-positive S. aureus ATCC 29737 and among different bacterial strains including Gram-positive B. subtilis ATCC 6633 and M. luteus ATCC 10240 and Gram-negative E. coli ATCC K88 and K. pneumoniae ATCC 10031. Nanoparticles exhibited the highest antibacterial (92%) and antibiofilm activity (17%) against B. subtilis ATCC 6633 in the dark. Interestingly, the nitrogen-centered free radical DPPH is scavenged (100%) by nanoplates due to its large surface area (342.2 m2/g) and the presence of the F2+ defect state. The concentration-dependent interaction with an antioxidant defense system (ascorbic acid (AA)) highlights nanoparticles as potent scavengers of O2•- in the dark. Thus, our findings establish guidelines for the selection of MgO nanostructures for diverse therapeutic applications.


Assuntos
Antioxidantes/farmacologia , Óxido de Magnésio/farmacologia , Nanopartículas Metálicas/química , Oxidantes/farmacologia , Antioxidantes/química , Bactérias/metabolismo , Radical Hidroxila , Óxido de Magnésio/química , Oxidantes/química , Oxirredução , Espécies Reativas de Oxigênio
9.
Mol Biol Rep ; 45(5): 663-673, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29872937

RESUMO

The present work is emphasised with the herbicidal tolerance of Azolla pinnata R.Br. and its modulation with TiO2 nano-particle. Both carbohydrate and nitrogen metabolism were effected with 2,4-D as herbicide and in few cases TiO2-NP had recovered few detrimental effects. From the nutrient status in Azolla it recorded the recovery of nitrogen as well as potassium by TiO2-NP but not in case of phosphorus. However, a conversion of nitrate to ammonium was more induced by TiO2-NP under herbicidal toxicity. Similar results were obtained for inter-conversion of amino acid-nitrate pool, but no changes with glutamine synthase activity with TiO2-NP. Initially, the effects of 2,4-D was monitored with changes of chlorophyll content but had not been recovered with nanoparticle. Photosynthetic reserves expressed as both total and reducing sugar were insensitive to TiO2-NP interference but activity of soluble and wall bound invertase was in reverse trend as compared to control. The 2,4-D mediated changes of redox and its oxidative stress was ameliorated in plants with over expressed ADH activity. As a whole the Azolla bio system with TiO2 supplementation may be useful in sustenance against 2,4-D toxicity through recovery of nitrogen metabolism. Thus, Azolla-TiO2-NP bio system would be realised to monitor the herbicidal toxicity in soil and its possible bioremediation.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Gleiquênias/fisiologia , Titânio/metabolismo , Biodegradação Ambiental , Clorofila/metabolismo , Nanopartículas Metálicas , Nanopartículas , Nitrogênio/metabolismo , Oxirredução , Estresse Oxidativo/fisiologia , Fotossíntese , Potássio/metabolismo , Poluentes Químicos da Água
10.
EMBO Rep ; 15(7): 775-83, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24878851

RESUMO

A20 has been suggested to limit NF-κB activation by removing regulatory ubiquitin chains from ubiquitinated substrates. A20 is a ubiquitin-editing enzyme that removes K63-linked ubiquitin chains from adaptor proteins, such as RIP1, and then conjugates them to K48-linked polyubiquitin chains to trigger proteasomal degradation. To determine the role of the deubiquitinase function of A20 in downregulating NF-κB signaling, we have generated a knock-in mouse that lacks the deubiquitinase function of A20 (A20-OTU mice). These mice are normal and have no signs of inflammation, have normal proportions of B, T, dendritic, and myeloid cells, respond normally to LPS and TNF, and undergo normal NF-κB activation. Our results thus indicate that the deubiquitinase activity of A20 is dispensable for normal NF-κB signaling.


Assuntos
Cisteína Endopeptidases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , NF-kappa B/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Cisteína Endopeptidases/genética , Análise Mutacional de DNA , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Genótipo , Sistema Imunitário/citologia , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Imunofenotipagem , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipopolissacarídeos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Fenótipo , Choque/induzido quimicamente , Choque/genética , Choque/imunologia , Choque/metabolismo , Choque/mortalidade , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Fator de Necrose Tumoral alfa/farmacologia
11.
Physiol Mol Biol Plants ; 22(3): 371-380, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27729723

RESUMO

In the present experiment a pteridophytic species Azolla and an angiospermic species Vernonia were evaluated on the basis of cellular reactivity for herbicidal action through ongoing concentrations. Initially, both the species recorded a significant activity of IAA-oxidase as mark of IAA metabolism with herbicidal sensitivity. Still, Vernonia species were more affected on 2,4-D mediated auxin catabolism. The loss of auxin concentrations on the tissues by 2,4-D reaction was also reflected on growth parameters including relative growth rate and chlorophyll biosynthesis. In a dose dependent manner Vernonia plants were more affected with loss of chlorophyll content and decline in relative growth rate. On the other hand, both those parameters were adjusted significantly with 2,4-D accumulation in Azolla. The stability of cellular metabolism was documented by significant down regulation of protein and lipid peroxidation with concomitant moderation to superoxide and hydrogen peroxide accumulation. The later two were more vulnerable to damage in the Vernonia plant with profuse accumulation of protein and lipid peroxidation products. Similarly, tissue specific reaction to superoxide and hydrogen peroxide accumulation were distinctly demarcated in two species significantly. As a whole, the cellular responses and metabolite distribution to 2,4-D sensitization are the features to describe bio-indices for aquatic fern species Azolla with comparison to angiospermic species Vernonia.

12.
ACS Appl Mater Interfaces ; 16(21): 27532-27540, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38743018

RESUMO

Robust ferroelectricity in HfO2-based ultrathin films has the potential to revolutionize nonvolatile memory applications in nanoscale electronic devices because of their compatibility with the existing Si technology. However, to fully exploit the potential of ferroelectric HfO2-based thin films, it is crucial to develop strategies for the controlled stabilization of various HfO2-based polymorphs in nanoscale heterostructures. This study demonstrates how substrate-orientation-induced anisotropic strain can engineer the crystal symmetry, structural domain morphology, and growth orientation of ultrathin Hf0.5Zr0.5O2 (HZO) films. Epitaxial ultrathin HZO films were grown on the heterostructures of (001)- and (110)-oriented La2/3Sr1/3MnO3/SrTiO3 (LSMO/STO) substrate. Various structural analyses revealed that the (110)-oriented substrate promotes a higher degree of structural order (crystallinity) with improved stability of the (111)-oriented orthorhombic phase (Pca21) of HZO. Conversely, the (001)-oriented substrate not only induces a distorted orthorhombic structure but also facilitates the partial stabilization of nonpolar phases. Electrical measurements revealed robust ferroelectric properties in epitaxial thin films without any wake-up effect, where the well-ordered crystal symmetry stabilized by STO(110) facilitated better ferroelectric characteristics. This study suggests that tuning the epitaxial growth of ferroelectric HZO through substrate orientation can improve the stability of the metastable ferroelectric orthorhombic phase and thereby offer a better understanding of device applications.

13.
Toxicol Appl Pharmacol ; 267(1): 57-73, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23276653

RESUMO

Diabetes is a menacing problem, particularly to inhabitants of groundwater arsenic contaminated areas needing new medical approaches. This study examines if PLGA loaded nano-insulin (NIn), administered either intraperitoneally (i.p.) or through oral route, has a greater cost-effective anti-hyperglycemic potential than that of insulin in chronically arsenite-fed hyperglycemic mice. The particle size, morphology and zeta potential of nano-insulin were determined using dynamic light scattering method, scanning electronic and atomic force microscopies. The ability of the nano-insulin (NIn) to cross the blood-brain barrier (BBB) was also checked. Circular dichroic spectroscopic (CD) data of insulin and nano-insulin in presence or absence of arsenic were compared. Several diabetic markers in different groups of experimental and control mice were assessed. The mitochondrial functioning through indices like cytochrome c, pyruvate-kinase, glucokinase, ATP/ADP ratio, mitochondrial membrane potential, cell membrane potential and calcium-ion level was also evaluated. Expressions of the relevant marker proteins and mRNAs like insulin, GLUT2, GLUT4, IRS1, IRS2, UCP2, PI3, PPARγ, CYP1A1, Bcl2, caspase3 and p38 for tracking-down the signaling cascade were also analyzed. Results revealed that i.p.-injected nano-encapsulated-insulin showed better results; NIn, due to its smaller size, faster mobility, site-specific release, could cross BBB and showed positive modulation in mitochondrial signaling cascades and other downstream signaling molecules in reducing arsenic-induced-hyperglycemia. CD data indicated that nano-insulin had less distorted secondary structure as compared with that of insulin in presence of arsenic. Thus, overall analyses revealed that PLGA nano-insulin showed better efficacy in combating arsenite-induced-hyperglycemia than that of insulin and therefore, has greater potentials for use in nano-encapsulated form.


Assuntos
Arsênio/toxicidade , Hiperglicemia/induzido quimicamente , Hiperglicemia/prevenção & controle , Insulina/administração & dosagem , Ácido Láctico/administração & dosagem , Nanopartículas/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Feminino , Hiperglicemia/metabolismo , Insulina/química , Insulina/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo , Masculino , Camundongos , Nanopartículas/química , Ácido Poliglicólico/química , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Distribuição Aleatória
14.
AAPS PharmSciTech ; 14(3): 1219-26, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23934434

RESUMO

Targeting drug formulations to specific tissues and releasing the bioactive content in response to a certain stimuli remains a significant challenge in the field of biomedical science. We have developed a nanovehicle that can be used to deliver "drugs" to "specific" tissues. For this, we have simultaneously modified the surface of the nanovehicle with "drugs" and "tissue-specific ligands". The "tissue-specific ligands" will target the nanovehicle to the correct tissue and release the "drug" of interest in response to specific stimuli. We have synthesised a "lactose surface-modified gold nanovehicle" to target liver cells and release the model fluorescent drug (coumarin derivative) in response to the differential glutathione concentration (between blood plasma and liver cells). Lactose is used as the liver-specific targeting ligand given the abundance of L-galactose receptors in hepatic cells. The coumarin derivative is used as a fluorescent tag as well as a linker for the attachment of various biologically relevant molecules. The model delivery system is compatible with a host of different ligands and hence could be used to target other tissues as well in future. The synthesised nanovehicle was found to be non-toxic to cultured human cell lines even at elevated non-physiological concentrations as high as 100 µg/mL. We discover that the synthesised gold-based nanovehicle shows considerable stability at low extracellular glutathione concentrations; however coumarin is selectively released at high hepatic glutathione concentration.


Assuntos
Portadores de Fármacos , Ouro/química , Fígado/metabolismo , Nanopartículas Metálicas/química , Corantes Fluorescentes/química , Glutationa/química , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Ann Pediatr Cardiol ; 16(2): 127-130, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37767178

RESUMO

COVID-19 infection has myriad manifestations from self-limiting illness to stormy multi-organ failure. A 28-year-old woman negative for COVID reverse transcription-polymerase chain reaction underwent an uneventful elective device closure of atrial septal defect on intubation anesthesia. While a brief postprocedural endotracheal bleed was noted, significant hypoxia and respiratory distress ensued after extubation with biventricular dysfunction, pleural effusion, and radiographic evidence of acute respiratory distress syndrome. COVID antibodies were positive, and inflammatory markers were elevated. After a conservative multipronged medical management including anticoagulation, antibiotics, aspirin, beta-blocker, diuretics, and sildenafil, she improved in 1 week. The clinical course during this pandemic era gives a possibility of a post-COVID inflammatory syndrome as a potential etiology.

16.
Cureus ; 15(9): e45260, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37846260

RESUMO

Background Atrial septal defect (ASD) closure with significant left-to-right shunt and concurrent comorbidities poses challenges for intervention. A fenestrated atrial septal defect (FASD) device is a viable option for patients who cannot undergo complete occlusion due to hemodynamic and medical reasons. This study explores the use of FASD occluders in patients with secundum ASD and associated comorbidities where complete occlusion is difficult. Methodology This retrospective study collected the details of patients recommended for FASD closure diagnosed with significant secundum ASD and who had additional comorbidities between July 2015 and July 2023 in a tertiary cardiac center in eastern India. Among this cohort, patients who underwent FASD device placement were subjected to a comprehensive analysis. Results In total, 16 patients diagnosed with secundum ASD, characterized by significant left-to-right shunt and concurrent comorbidities, were considered for FASD closure during the study period. Ultimately, 13 patients (first group) underwent fenestrated atrial septal occluder implantation. The average age was 45.07 years, with the majority being females (n = 9). Comorbidities among this cohort included substantial left ventricular diastolic dysfunction (n = 7), left ventricular diastolic dysfunction coupled with moderate pulmonary hypertension (n = 1), severe pulmonary hypertension (n = 1), severe pulmonary valvular stenosis with right ventricular diastolic dysfunction (n = 2), and systemic lupus erythematosus (SLE) (n = 2). From this cohort, three patients did not undergo the intervention. The second group consisted of an elderly patient with severe left ventricular diastolic dysfunction, a young adult with a history of left atrial arrhythmia, and a child with Duchenne muscular dystrophy (DMD). The average ASD size among patients who underwent the intervention was 26.38 mm, with a thick-to-thick dimension measuring 31.15 mm. The procedure was successful in all 13 patients, with the most frequently used device being a 34 mm occluder (range = 28-40 mm). All devices, excluding the initial one, were custom-made atrial septal occluders (Lifetech Scientific). Among the patients, 12 exhibited left-to-right fenestration flow, while one patient experienced fenestration constriction, likely due to occluder overcrowding. The first patient had a handmade 5 mm fenestration in a 40 mm Amplatzer septal occluder, which got closed off at the one-year follow-up. The procedure was well-tolerated hemodynamically in all patients, with no major complications during the peri-procedural period. Short-term follow-up indicated favorable patient progress. Conclusions FASD closure emerges as a pivotal alternative for intricate scenarios involving secundum ASD coupled with concurrent comorbidities, offering individualized tailored solutions. Alongside the conventional associated comorbidities, such as left ventricular diastolic dysfunction and pulmonary hypertension, FASD devices hold the potential to extend their benefits to patients grappling with other complexities, including severe pulmonary valvular stenosis, SLE, predisposition to left atrial arrhythmia, and conditions like DMD. Ensuring meticulous evaluation of patient suitability and providing ongoing vigilant care becomes paramount for achieving optimal outcomes. The validation of these findings and the broadening of the comprehension of this approach necessitate further comprehensive investigations.

17.
Zhong Xi Yi Jie He Xue Bao ; 10(12): 1433-42, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23257138

RESUMO

OBJECTIVE: To evaluate the ameliorative efficacy of dihydroxy-isosteviol methyl ester (DIME) of Pulsatilla nigricans extract in arsenic-induced DNA damage in testis cells of mice. METHODS: The mice were treated with sodium arsenite (SA) solution intragastrically at a dose of 20 mg/kg per day and examined at 30, 60, and 90 d after treatment. We divided SA-intoxicated mice into two sub-groups: one fed with DIME at a dose of 35 mg/kg and the other with 85% alcohol. We analyzed the expressions of apoptotic signal proteins like CYP1A1, p53 and caspase 3, ascertained the level of cellular and DNA damage and estimated the level of testicular-toxicity biomarkers. We studied the interaction of DIME with calf thymus DNA as target through circular dichroism spectra and melting temperature profiles. RESULTS: We observed an elevation in all apoptotic and toxicity biomarkers leading to cellular and DNA damage in the SA-intoxicated mice which showed significant inhibition or reversal on administration of DIME. Results also showed that DIME interacted with DNA, bringing in discernible changes in structure and conformation. CONCLUSION: DIME has potentials for therapeutic use in amelioration of arsenic-induced reproductive toxicity.


Assuntos
Apoptose/efeitos dos fármacos , Diterpenos do Tipo Caurano/farmacologia , Extratos Vegetais/farmacologia , Pulsatilla/química , Espermátides/efeitos dos fármacos , Animais , Arsênio/toxicidade , Arsenitos/toxicidade , Dano ao DNA/efeitos dos fármacos , Masculino , Camundongos , Compostos de Sódio/toxicidade , Espermátides/citologia
18.
Zhong Xi Yi Jie He Xue Bao ; 10(2): 210-27, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22313889

RESUMO

OBJECTIVE: To examine if potentiated homeopathic drug Arsenicum Album 30C (Ars Alb 30C) can reduce sodium arsenite-induced toxicity in Escherichia coli. METHODS: E. coli were exposed to low arsenite insult after they grew up to log phase in standard Luria-Bertani medium. E. coli were treated with 1 or 2 mmol/L sodium arsenite alone (control), or Ars Alb 30C was added to the medium of a subset of sodium arsenite-treated bacteria (drug-treated), or homeopathically agitated alcohol was added to the medium containing a subset of sodium arsenite-treated bacteria (placebo-treated). A sub-set of untreated E. coli served as the negative control. Glucose uptake, specific activities of hexokinase, lipid peroxidase (LPO), superoxide dismutase (SOD) and catalase, intra- and extra-cellular sodium arsenite content, cell growth, cell membrane potential, DNA damage, intracellular reactive oxygen species (ROS), adenosine triphosphate (ATP) and free glutathione content and expressions of arsB and ptsG gene in normal control, sodium arsenite-treated, drug-treated and placebo-treated E. coli were analyzed. Treatments were blinded and randomized. RESULTS: In sodium arsenite-treated E. coli, glucose uptake, intracellular ROS, LPO and DNA damage increased along with decrease in the specific activities of hexokinase, SOD and catalase, intracellular ATP and free glutathione contents and cell membrane potential and growth, and there were increases in expression levels of arsB gene and ptsG gene. Ars Alb 30C administration reduced arsenic toxicity in E. coli by inhibiting generation of ROS and increasing tolerance to arsenite toxicity and cell growth. CONCLUSION: Ars Alb 30C ameliorated arsenic toxicity and DNA damage, validating efficacy of ultra-highly diluted remedies used in homeopathy.


Assuntos
Arsenicais/antagonistas & inibidores , Arsenitos/toxicidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Homeopatia , Espécies Reativas de Oxigênio/metabolismo , Dano ao DNA , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Peroxidação de Lipídeos , Regulação para Cima
19.
Zhong Xi Yi Jie He Xue Bao ; 10(3): 337-46, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22409925

RESUMO

OBJECTIVE: To examine to what degree an ultra-highly diluted homeopathic remedy, Arnica Montana 30C (AM-30C), used in the treatment of shock and injury, can modulate the expression of nucleotide excision repair genes in Escherichia coli exposed to ultraviolet (UV) irradiation. METHODS: E. coli were cultured to their log phase in a standard Luria-Bertani medium and then exposed to sublethal doses of UV irradiation at 25 and 50 J/m(2) for 22.5 and 45 s, respectively. The UV-exposed bacteria were then supplemented with either AM-30C (drug) or placebo (P-30C). The drug-treated and placebo-treated bacteria were subjected to assay for DNA damage and oxidative stress 90 min after UV exposure. Several protocols like comet assay, gel electrophoresis for DNA ladder and intracellular reactive oxygen species (ROS) generation, and biomarker measurement like superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) were conducted. The mRNA expressions of the excision repair genes like ultraviolet repair uvrA, B and C genes (or also known as excision repair genes) were estimated by reverse transcription-polymerase chain reaction method. RESULTS: The UV-exposed bacteria showed DNA damage and oxidative stress, as revealed by an increase in ROS generation, and a decrease in SOD, CAT and GSH activities. As compared to placebo, the AM-30C-treated bacteria showed less DNA damage and oxidative stress as manifested by a decrease in ROS generation, and an increase in SOD, CAT and GSH activities. AM-30C also up-regulated the expression of repair genes as compared to the control. CONCLUSION: AM-30C helped repair the DNA damage through up-regulation of repair genes and also ameliorated the oxidative stress through the reduction of ROS generation and suitable modulation of anti-oxidative stress enzymes.


Assuntos
Arnica , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/genética , Escherichia coli/efeitos dos fármacos , Homeopatia , Catalase/metabolismo , Ensaio Cometa , Escherichia coli/efeitos da radiação , Glutationa/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Raios Ultravioleta
20.
Zhong Xi Yi Jie He Xue Bao ; 10(5): 546-54, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22587977

RESUMO

OBJECTIVE: To examine if a homeopathic mother tincture (Phytolacca Decandra) is capable of precipitating silver nanoparticles from silver nitrate (AgNO(3)) and to characterize the biosynthesized nanoparticles for evaluating their biological activities. METHODS: A total of 100 mg of AgNO(3) was added to 20mL of Milli-Q water and stirred vigorously. Then 5mL of the homeopathic mother tincture of Phytolacca Decandra (ethanolic root extract of Phytolacca decandra) was added and stirred continuously. Reduction took place rapidly at 300K and completed in 10 min as shown by stable light greenish-yellow color of the solution which gave colloid of silver nanoparticles. The colloid solution was then centrifuged at 5000×g to separate the nanoparticles for further use. The nanoparticles were characterized by spectroscopic analysis, particle size analysis and zeta potential measurements, and morphology was analyzed by atomic force microscopy. The drug-DNA interaction was determined by circular dichroism spectrophotometry and melting temperature profiles by using calf thymus DNA as the target. The biological activities were determined using a cancer cell line A549 in vitro and using bacteria Escherichia coli and fungus Saccharomyces cerevisiae as test models. RESULTS: Phytolacca Decandra precipitated silver nanoparticles in ambient conditions. The nanoparticles had 91 nm particle size, with polydispersity index of 0.119 and zeta potential of -15.6 mV. The silver nanoparticles showed anticancer and antibacterial properties, but no clear antifungal properties. CONCLUSION: This could be a novel environment-friendly method to biosynthesize silver nanoparticles using a cost-effective, nontoxic manner. The homeopathic mother tincture may utilize this property of nano-precipitation in curing diseases or disease symptoms.


Assuntos
Química Verde , Homeopatia , Nanopartículas Metálicas , Phytolacca/química , Nitrato de Prata/química , Materia Medica/química , Tamanho da Partícula , Extratos Vegetais/química , Prata/química
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