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1.
Environ Monit Assess ; 196(5): 473, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662282

RESUMEN

Aerosol optical depth (AOD) serves as a crucial indicator for assessing regional air quality. To address regional and urban pollution issues, there is a requirement for high-resolution AOD products, as the existing data is of very coarse resolution. To address this issue, we retrieved high-resolution AOD over Kanpur (26.4499°N, 80.3319°E), located in the Indo-Gangetic Plain (IGP) region using Landsat 8 imageries and implemented the algorithm SEMARA, which combines SARA (Simplified Aerosol Retrieval Algorithm) and SREM (Simplified and Robust Surface Reflectance Estimation). Our approach leveraged the green band of the Landsat 8, resulting in an impressive spatial resolution of 30 m of AOD and rigorously validated with available AERONET observations. The retrieved AOD is in good agreement with high correlation coefficients (r) of 0.997, a low root mean squared error of 0.035, and root mean bias of - 4.91%. We evaluated the retrieved AOD with downscaled MODIS (MCD19A2) AOD products across various land classes for cropped and harvested period of agriculture cycle over the study region. It is noticed that over the built-up region of Kanpur, the SEMARA algorithm exhibits a stronger correlation with the MODIS AOD product compared to vegetation, barren areas and water bodies. The SEMARA approach proved to be more effective for AOD retrieval over the barren and built-up land categories for harvested period compared with the cropping period. This study offers a first comparative examination of SEMARA-retrieved high-resolution AOD and MODIS AOD product over a station of IGP.


Asunto(s)
Aerosoles , Contaminantes Atmosféricos , Ciudades , Monitoreo del Ambiente , Imágenes Satelitales , India , Monitoreo del Ambiente/métodos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Algoritmos
2.
J Kidney Cancer VHL ; 10(4): 1-6, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37814604

RESUMEN

Our study aims to discern the immediate and intermediate-term oncological outcomes of the patients with small renal mass and who were surgically unfit or were having a bilateral tumor and underwent radiofrequency ablation (RFA) of the mass. We retrospectively and prospectively analyzed the status of the patients who were diagnosed to have small renal masses and were biopsy-proven renal cell carcinoma (RCC) cases, who underwent RFA at our institute from the year 2013 to 2022. Patients were followed-up for 3 years. Data regarding complications were analyzed for all patients who underwent renal RFA along with the 3-year recurrence-free survival (RFS) rate. A total of 28 patients were eligible for the study based on our inclusion and exclusion criteria. Their renal function was recorded. They underwent RFA and were followed-up for a period of 3 years for RFS. Four patients out of the total had immediate complications, out of which two developed a hematoma. Three-year-follow-ups showed six recurrences, overall having 78.6% RFS. Post-procedural renal function was stable as documented by Estimated glomerular filtration rate. Oncological results of RFA in patients with small renal masses who are surgically unfit are associated with a low risk of immediate and intermediate-term deterioration of renal function.

3.
Cephalalgia ; 43(2): 3331024221143540, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36739514

RESUMEN

OBJECTIVE: We aimed to determine the association between iron deficiency anemia and chronic daily headache. METHODS: This case-control study was conducted in a tertiary care center in Dehradun, India. One hundred patients with chronic daily headache were randomly selected for the study with an equal number of controls. Subsets of chronic daily headache were diagnosed as per the 3rd edition of the International Classification of Headache Disorders. The study participants were assessed for iron deficiency anemia. RESULTS: The mean age of the patients was 51.1 ± 22.1 years. Male: female ratio was 1:1.08. Chronic migraine was present in 62 (62%), tension-type headache in 23 (23%), and new daily persistent headache in 15 (15%) patients. The majority (96%) of patients had chronic daily headache of mild to moderate severity. Chronic daily headache was of long duration in all patients. Sixty-four (64%) patients had anemia of which 51 (51%) patients had iron deficiency anemia. Iron deficiency anemia showed a significant association with chronic daily headache (p < 0.001), but not with its type, subtype, and duration. Severe iron deficiency anemia had a significant association with the severity of chronic daily headache (p = 0.021). Serum iron, ferritin, total iron-binding capacity, and transferrin saturation also had a significant association with chronic daily headache (p < 0.05 for each), but not with its type, subtype, duration, and severity. Logistic regression analysis showed that iron deficiency anemia, total iron-binding capacity, and transferrin saturation had an independent association with chronic daily headache (p < 0.05 for each). CONCLUSIONS: Iron deficiency anemia had an independent association with chronic daily headache. Severe iron deficiency anemia was related to the severity of chronic daily headache.


Asunto(s)
Anemia Ferropénica , Trastornos de Cefalalgia , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anemia Ferropénica/complicaciones , Anemia Ferropénica/epidemiología , Estudios de Casos y Controles , Trastornos de Cefalalgia/complicaciones , Trastornos de Cefalalgia/epidemiología , Hierro , Transferrinas
4.
Pharmacy (Basel) ; 11(1)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36827665

RESUMEN

(1) Background: Hyperphosphatemia is correlated with an increased rate of mortality and morbidity due to cardiovascular diseases in chronic kidney disease (CKD) patients. It can be improved by restricting dietary intake of phosphate and oral phosphate binders, such as lanthanum carbonate and sevelamer carbonate. (2) Objective: To evaluate the clinical efficacy of sevelamer carbonate in comparison to lanthanum carbonate as phosphate binders for the treatment of hyperphosphatemia in CKD patients. (3) Methods: A randomized control comparative clinical study was conducted for one year on 150 CKD patients associated with hyperphosphatemia, divided into two groups, i.e., Group 1 (n = 75) treated with sevelamer carbonate 800 mg thrice daily and Group 2 (n = 75) treated with lanthanum carbonate 500 mg thrice daily. The patients were assessed at the time of enrollment in the study, after three months and after six months from baseline for different parameters, i.e., complete blood count, liver function tests, renal function tests, electrolytes, and serum phosphate level. (4) Results: 150 CKD patients aged 51-60 participated in the study. The mean age of patients was 54 ± 4.6 years, and males (55.71%) were more common than females (44.29%). Hypertension was the common comorbidity in both groups with chronic kidney disease. After six months of treatment, the mean serum phosphate level was significantly decreased from 8.31 ± 0.09 mg/dL to 5.11 ± 0.18 (38%) in Group 1 and from 8.79 ± 0.28 mg/dl to 4.02 ± 0.12 (54%; p < 0.05) in Group 2, respectively. In both groups, no significant difference was found in other parameters such as parathyroid hormone, calcium, uric acid, LFT, RFT, CBC, etc. (5) Conclusion: Lanthanum carbonate is more efficacious in lowering serum phosphate concentrations and effectively managing hyperphosphatemia as compared to sevelamer carbonate.

5.
J Inorg Biochem ; 238: 112059, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36345069

RESUMEN

A series of nine new complexes of ruthenium(II), rhodium(III), and iridium(III) incorporated with pyrazoline-based ligands were synthesized and characterized by various spectroscopic techniques such as FTIR, 1H NMR, 13C NMR, UV-Vis spectroscopy, ESI-MS spectrometry and X-ray crystallographic studies. All the synthesized compounds were assessed for their antibacterial abilities against Gram-positive and Gram-negative bacterial strains. The compounds showed better antibacterial activity against two Gram-positive bacteria (Staphylococcus aureus and Bacillus Thuringiensis), with activities superior to standard kanamycin. Antioxidant studies revealed the mild radical scavenging proficiency of the compounds. DNA binding studies using fluorescence spectroscopy showed that the compounds could bind to Salmon Milt DNA electrostatically via external contact and groove surface binding with moderate affinity. The synthesized complexes were tested for anticancer activity using cell cytotoxicity and apoptosis assays in Dalton's lymphoma (DL) cell lines. The findings were compared to cisplatin (the standard drug) under identical experimental conditions. The cell viability results showed that complex 7 induced higher cytotoxicity in the DL cell line than the other tested compounds. The results of the molecular docking analysis further suggest that selective complexes have complete contact with the active amino acids sites of anti-apoptotic Bcl-2 family protein.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Rodio , Rutenio , Rutenio/química , Iridio/farmacología , Iridio/química , Complejos de Coordinación/química , Rodio/química , Simulación del Acoplamiento Molecular , Proliferación Celular , Antineoplásicos/farmacología , Antineoplásicos/química , Ligandos , Antibacterianos/farmacología , Antibacterianos/química , ADN/química
6.
J Forensic Leg Med ; 90: 102397, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35841695

RESUMEN

AIM: This research aims to investigate the utility of the Near Infra-Red (NIR) photographic technique in visualizing forensic evidence in a post-mortem examination. MATERIAL AND METHODS: A total of twenty-six deceased (male: n = 15; female: n = 11) were brought to the Mortuary of King George's Medical University, Chowk, Lucknow, Uttar Pradesh, India (226003), and were used to investigate the applicability of the human visible spectrum (HVS) & near-infrared photography. In the investigation, a modified Nikon D5300 crop-framed digital single-lens reflex camera was used for NIR Photography in combination with a Micro-Nikkor 105 mm, f/2.8, (Nikon Inc., Melville, NY, USA), Hoya R72 (760nm-860nm) infrared filter and a Nikon D5600 crop-framed digital single-lens reflex camera in combination with Nikkor 50mm lens for Human Visible Spectrum (HVS) Photography. RESULTS: The finding of the study reported that the application of the NIR photography would be the best of the investigative techniques for visualization and photo-documentation of forensically relevant post-mortem findings, such as - trace evidences (e.g., blood spots & soil particles on dark clothing), in external findings (e.g., contusion on victim's body) also for internal findings in a road traffic accident (RTA), gunshot, and drowning victim (e.g., mud particles in the trachea of drowning victim & localizing contusion of the scalp in road traffic accident cases). CONCLUSION: Human visible spectrum (HVS) photographs taken with Nikon D5600 provides substantial evidence for documentation purpose, the best results for trace evidence & contusion visualization in Post-mortem examination of the deceased were achieved with the NIR Photography in combination with indirect sunlight & room light as an infrared light source. (At a wavelength of 760nm-860nm).


Asunto(s)
Contusiones , Ahogamiento , Autopsia , Femenino , Medicina Legal/métodos , Humanos , Masculino , Fotograbar/métodos
7.
J Struct Biol ; 214(1): 107829, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34974142

RESUMEN

In plant chloroplasts, thiol regulation is driven by two systems. One relies on the activity of thioredoxins through their light dependent reduction by ferredoxin via a ferredoxin-thioredoxin reductase (FTR). In the other system, a NADPH-dependent redox regulation is driven by a NADPH-thioredoxin reductase C (NTRC). While the thioredoxin system has been deeply studied, a more thorough understanding of the function of this plant specific NTRC is desirable. NTRC is a single polypeptide harbouring a thioredoxin domain (Trx) at the C-terminus of a NADPH-dependent Thioredoxin reductase (TrxR). To provide functional and structural insights, we studied the crystal structure of the TrxR domain of the NTRC from Chlamydomonas reinhardtii (CrNTRC, Cre01.g054150.t1.2) and its Cys136Ser (C136S) mutant, which is characterized by the mutation of the resolving cysteine in the active site of the TrxR domain. Furthermore, we confirmed the role of NTRC as electron donor for 2-Cys peroxiredoxin (PRX) also in C. reinhardtii. The structural data of TrxR were employed to develop a scheme of action which addresses electron transfer between TrxR and Trx of NTRC and between NTRC and its substrates.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Chlamydomonas reinhardtii , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , NADP , Oxidación-Reducción , Oxidorreductasas/metabolismo , Reductasa de Tiorredoxina-Disulfuro/genética , Reductasa de Tiorredoxina-Disulfuro/metabolismo , Tiorredoxinas/metabolismo
8.
Eur J Pharm Sci ; 171: 106125, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35033697

RESUMEN

Vascular endothelial growth factor (VEGF) is considered as one of the vital growth factors for angiogenesis, which is primarily responsible for the progress and maintenance of new vascular network in tumor. Numerous studies report that inhibition of VEGF-induced angiogenesis is a potent technique for cancer suppression. Recently, RNA interference, especially small interfering RNA (siRNA) signified a promising approach to suppress the gene expression. However, the clinical implementation of biological macromolecules such as siRNA is significantly limited because of stability and bioavailability issues. Herein, self-assembled peptide nanospheres have been generated from L,L-cyclic peptides using hydrophobic (Trp), positively charged (Arg) and cysteine (Cys) amino acid residues and demonstrated as vehicles for intracellular delivery of VEGF siRNA and VEGF antisense oligonucleotide. Formation of peptide nanostructures is confirmed by HR-TEM, AFM, SEM and DLS analysis. Possible mechanism of self-assembly of the cyclic peptides and their binding with macromolecules are demonstrated by in-silico analysis. Gel electrophoresis reveals that the newly generated peptide based organic materials exhibit strong binding affinity toward siRNAs / antisense oligonucleotides (ASOs) at optimum concentration. Flow cytometry and confocal microscopy results confirm the efficiency of the new biomaterials toward the intracellular delivery of fluorescent labeled siRNA / ASOs. Furthermore, VEGF expression evaluated by western blot and RT-PCR upon the delivery of functional VEGF siRNA/ASOs suggests that very low concentrations of VEGF siRNA/ASOs cause significant gene knockdown at protein and mRNA levels, respectively.


Asunto(s)
Nanosferas , Factor A de Crecimiento Endotelial Vascular , Línea Celular Tumoral , Citoplasma/metabolismo , Péptidos Cíclicos , ARN Interferente Pequeño/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
Environ Sci Pollut Res Int ; 29(14): 20007-20016, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33179183

RESUMEN

Inevitably increase in plastic demand has resulted in an overgrowing production on a global scale. The utilization of plastics has been applied to a number of industries as it is a durable, moldable, and inexpensive material. High exploitation of plastic had resulted in a hefty amount of waste production, which is not easy to recycle due to its non-degradable nature and results in landfills. Nowadays, waste to energy processes such as pyrolysis has emerged as a superlative process for the management of plastic waste by converting it into useful products. On the other hand, the employment of carbon nanotubes (CNT's) has shown high growth in their production. CNT's were generally synthesized from conventional gases like methane, ethane, and ethylene. Plastic waste can be utilized to substitute the feed material for the CNT synthesis via pyrolysis method. In this study, a two-step pyrolysis process was investigated for product recovery and CNT's production. The first steps consisted of catalytic and non-catalytic degradation of mixed plastic waste in a vertical fixed bed reactor at 500 °C with a heating rate of 20 °C/min for the production of pyrolytic oil and gases and were analyzed. The second step consists of the employment of catalytic pyrolysis gases in a horizontal tube reactor maintained at a temperature of 800 °C over a bed of catalyst for the synthesis of CNT's via catalytic vapor deposition (CVD) technique. It was established that the use of catalyst decreases the oil phase production from 80.5 to 64%, char from 9 to 6.5% while an increase in gas phase production from 10.5 to 29.5% was reported. The alteration of hydrocarbons to CNT's was investigated via pre- and post-GC analysis of the gas samples. Post gas investigation indicates an increased concentration of hydrogen in the sample. Also, the decline of hydrocarbon gases concentration was observed in post sample analysis. Also, transmission electron microscopy (TEM) analysis confirms the synthesis of CNT's.


Asunto(s)
Nanotubos de Carbono , Pirólisis , Catálisis , Gases , Plásticos , Reciclaje
10.
Ann Oper Res ; 319(1): 1045-1098, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-32836617

RESUMEN

Quality management has been widely discussed in the literature, and recent special issues on humanitarian supply chains and relief operations have emphasized the increasing importance of quality management in this key emerging area. In this paper, we provide an extensive literature review in the field of quality management in humanitarian operations and disaster relief management. Our comprehensive review, comprising 61 articles published from 2009 to 2018, leads to the identification of enablers (e.g., transparency, policy framework), challenges (e.g., financial services, identity protection), and theory development approaches, as well as numerous research gaps that must be addressed.

11.
Inf Syst Front ; : 1-25, 2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-34840520

RESUMEN

Social media has played a pivotal role in polarising views on politics, climate change, and more recently, the Covid-19 pandemic. Social media induced polarisation (SMIP) poses serious challenges to society as it could enable 'digital wildfires' that can wreak havoc worldwide. While the effects of SMIP have been extensively studied, there is limited understanding of the interplay between two key components of this phenomenon: confirmation bias (reinforcing one's attitudes and beliefs) and echo chambers (i.e., hear their own voice). This paper addresses this knowledge deficit by exploring how manifestations of confirmation bias contributed to the development of 'echo chambers' at the height of the Covid-19 pandemic. Thematic analysis of data collected from 35 participants involved in supply chain information processing forms the basis of a conceptual model of SMIP and four key cross-cutting propositions emerging from the data that have implications for research and practice.

12.
Protein Pept Lett ; 28(9): 996-1008, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33588715

RESUMEN

Serine is ubiquitously synthesized in all living organisms from the glycolysis intermediate 3-phosphoglycerate (PGA) by phosphoserine biosynthetic pathway, consisting of three different enzymes, namely: 3-phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Any functional defect or mutation in these enzymes may cause deliberating conditions, such as colon cancer progression and chemoresistance in humans. Phosphoserine aminotransferase (PSAT) is the second enzyme in this pathway that converts phosphohydroxypyruvate (PHP) to O-phospho-L-serine (OPLS). Humans encode two isoforms of this enzyme: PSAT1 and PSAT2. PSAT1 exists as a functional dimer, where each protomer has a large and a small domain; each large domain contains a Lys residue that covalently binds PLP. The PLP-binding site of human PSAT1 and most of its active site residues are highly conserved in all known PSAT structures except for Cys-80. Interestingly, Two PSAT structures from different organisms show halide binding near their active site. While the human PSAT1 shows a water molecule at this site with different interacting residues, suggesting the inability of halide binding in the human enzyme. Analysis of the human PSAT1 structure showed a big patch of positive charge around the active site, in contrast to the bacterial PSATs. Compared to human PSAT1, the PSAT2 isoform lacks 46 residues at its C-terminal tail. This tail region is present at the opening of the active site as observed in the other PSAT structures. Further structural work on human PSAT2 may reveal the functional importance of these 46 residues.


Asunto(s)
Eucariontes , Transaminasas , Animales , Dominio Catalítico , Eucariontes/enzimología , Eucariontes/genética , Humanos , Especificidad de la Especie , Transaminasas/química , Transaminasas/genética , Transaminasas/metabolismo
13.
J Environ Manage ; 261: 110112, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32001431

RESUMEN

The current energy demand and diminishing conventional fuels have forced researchers to find an alternative source of energy. Waste to energy is the current trend for converting waste materials (plastic waste) into valuable fuels. This article mainly discussed the detailed characterization of the pyrolytic products, their comparative analysis and the reaction mechanism at varying operating temperature. This article is a successor of part 1, which primarily focused on the characterization of different waste plastics, their TG analysis, the effect of reactor temperature on yield analysis in a batch reactor and their detailed degradation mechanism. Furthermore, the results presented in this article report the characterization of products at three processing temperatures of 450, 500 and 550 °C. The pyrolytic oils from all wastes excluding PS show a very low density ranging from 0.71 to 0.76 kg/m3, whereas PS pyrolytic density is reported between 0.86 and 0.88 kg/m3. The viscosity of oils increases with an increase in the processing temperature and is similar to the conventional fuels. The FTIR analysis of the products (oil & gases) obtained from HDPE, PP and mixed plastic waste (MIX) shows a large presence of alkanes and a higher presence of aromatics. PS analysis reported a large presence of aromatics (~75%). The GC-MS analysis of all pyrolytic oils from waste plastics, simulated wastes (virgin plastics) and distilled fraction of MIX pyrolysis oil is compared. The GC analysis of non-condensable gases at all processing temperature reports that MIX produce the maximum H2; HDPE, PS and MIX produces a high amounts of CH4 too. The formation of lower hydrocarbons (C5-C12) in pyrolysis oil shows a trend as MIX > PP > PS > HDPE, while for the heavier hydrocarbons (>C19) it is HDPE > PP > PS > MIX. The potential of the utilization of these products has been discussed in different sectors for future research.


Asunto(s)
Plásticos , Residuos , Hidrocarburos , Aceites , Temperatura
14.
Int J Pharm ; 563: 198-207, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-30953762

RESUMEN

Based on the cell penetrating ability of tryptophan-containing peptides, eight linear hexapeptides have been designed, synthesized and explored their efficiency toward the synthesis of gold nanoparticles under sunlight. The peptide generated gold nanoparticles (LP-GNPs) have been characterized by UV-visible spectroscopy, Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS) techniques. The binding ability of LP-GNPs toward siRNA, evaluated by gel electrophoresis indicates that sequence-selective-GNPs without any surface modifications exhibit strong affinity toward negatively charged biomolecules. Cellular uptake studies suggest that LP-GNPs exhibit significant uptake of fluorescence-labeled siRNA inside the cells as evidenced from Fluorescence Microscopy. In vitro gene silencing efficiency using newly generated GNPs revealed that above mentioned LP-GNPs efficiently down-regulate the level of GAPGH gene in colon cancer cells. Comparative gene silencing efficiency results indicate that anisotropic LP7-GNPs exhibit comparable efficacy to other existing carrier systems, such as Lipofectamine 2000 in presence of serum, mimicking in-vivo system. In conclusion, our results demonstrate that peptide-GNPs based delivery system for siRNA emerges to be effective to deliver RNAi therapeutics, uncovering new avenue in oncotherapy.


Asunto(s)
Arginina/administración & dosificación , Oro/administración & dosificación , Nanopartículas del Metal/administración & dosificación , Oligopéptidos/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Triptófano/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Técnicas de Transferencia de Gen , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Células HCT116 , Humanos
15.
A A Pract ; 12(5): 176-179, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30550435

RESUMEN

Multiple-system atrophy, a rare adult-onset neurodegenerative disease, is associated with autonomic dysfunction, features of parkinsonism, and cerebellar ataxia. This article discusses multiple-system atrophy pathophysiology, clinical presentation, and perioperative issues pertinent to anesthesia.


Asunto(s)
Anestesia de Conducción/normas , Anestesia General/normas , Atrofia de Múltiples Sistemas/diagnóstico , Atrofia de Múltiples Sistemas/cirugía , Guías de Práctica Clínica como Asunto/normas , Anestesia/métodos , Anestesia/normas , Anestesia de Conducción/métodos , Anestesia General/métodos , Humanos
16.
Artif Cells Nanomed Biotechnol ; 46(sup3): S763-S773, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30311806

RESUMEN

RNA interference shows a great strategy for biological studies; however, delivering of small interfering RNA (siRNA) remains challenging. Although several delivery vehicles, including cell-penetrating peptides, have been developed, their implementation is often restricted because of their endosomal entrapment. Herein, we report the formation of self-assembled nanostructures from rationally designed cyclic peptides and explore them for efficient delivery of functional biomacromolecules such as siRNA into mammalian cells. The newly obtained soft materials make stable complexes with siRNAs, thereby increasing their stability and deliver fluorescent labelled siRNA inside the cells as evident from confocal microscopy analysis. Flow cytometry analysis reveals that significant uptake of FAM-siRNA occurs in the presence of peptide nanostructures compared with siRNA alone. Peptide nanostructure-mediated delivery of very low concentration of siRNA causes significant knockdown of the target gene as observed at protein level by Western blot analysis, which is comparable to lipofectamine, commercially available transfection agent.


Asunto(s)
Portadores de Fármacos , Nanoestructuras/química , Péptidos Cíclicos , ARN Interferente Pequeño , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacología , Células HCT116 , Humanos , Nanoestructuras/ultraestructura , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacocinética , Péptidos Cíclicos/farmacología , ARN Interferente Pequeño/química , ARN Interferente Pequeño/farmacocinética , ARN Interferente Pequeño/farmacología
17.
Chem Commun (Camb) ; 54(32): 3981-3984, 2018 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-29611570

RESUMEN

Polyphenol functionalized silver nanoparticles (AgNPs) have been developed and demonstrated as colorimetric sensors for the selective detection of gadolinium. The newly obtained AgNP-Gd3+ conjugates exhibit high aqueous dispersibility and excitation dependent fluorescence emission. The conjugates offer multicolor bioimaging potential owing to their excellent luminescence properties.

18.
J Photochem Photobiol B ; 164: 306-313, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27721164

RESUMEN

In this article, light induced plant extract mediated one pot synthesis of silver nanoparticles (AgNPs) has been demonstrated and potential mechanistic insight in the synthesis has been investigated. Bioactive molecules containing medicinal plant Cassytha filiformis has been explored for the synthesis of silver nanoparticles. The as-synthesized silver nanoparticles were characterized by various analytical techniques including Ultraviolet-visible spectroscopy (UV-Vis), High Resolution Transmission Electron Microscopy (HR-TEM), Dynamic Light Scattering (DLS) and Fourier Transform Infrared Spectroscopy (FT-IR). Among different light sources (sunlight, room light, UV) applied the sunlight was found to be efficient external stimuli to induce rapid synthesis of AgNPs at room temperature. Modified DPPH assay indicated that polyphenolic compounds were most likely involved in the synthesis of AgNPs. Possible molecule responsible for the synthesis of AgNPs was identified, purified and characterized. Potential biomedical applications such as antibacterial, antifungal and anticancer activities of AgNPs have been evaluated. Irrespective of nature of pathogenic strains nanoparticles exhibited significant antibacterial activities against Gram positive (Streptococcus aureus) and Gram negative (Escherichia coli) bacterial pathogens. It showed higher activity on E. coli than on S. aureus. Distinct antifungal activity (MIC=5.244µg/ml) and remarkable anticancer activity (IC50=10µg/ml) was found against Candida albicans and HCT116 (colorectal carcinoma) cells, respectively. Taken together, these findings suggested that light induced plant generated silver nanoparticles could be used for various biomedical purposes.


Asunto(s)
Nanopartículas del Metal/química , Procesos Fotoquímicos , Plata/química , Microscopía Electrónica de Transmisión , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
19.
Biochim Biophys Acta ; 1860(7): 1508-18, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27102280

RESUMEN

BACKGROUND: Phosphoserine aminotransferase (PSAT) catalyses the second reversible step of the phosphoserine biosynthetic pathway in Trichomonas vaginalis, which is crucial for the synthesis of serine and cysteine. METHODS: PSAT from T. vaginalis (TvPSAT) was analysed using X-ray crystallography, enzyme kinetics, and molecular dynamics simulations. RESULTS: The crystal structure of TvPSAT was determined to 2.15Å resolution, and is the first protozoan PSAT structure to be reported. The active site of TvPSAT structure was found to be in a closed conformation, and at the active site PLP formed an internal aldimine linkage to Lys 202. In TvPSAT, Val 340 near the active site while it is Arg in most other members of the PSAT family, might be responsible in closing the active site. Kinetic studies yielded Km values of 54 µM and 202 µM for TvPSAT with OPLS and AKG, respectively. Only iodine inhibited the TvPSAT activity while smaller halides could not inhibit. CONCLUSION: Results from the structure, comparative molecular dynamics simulations, and the inhibition studies suggest that iodine is the only halide that can bind TvPSAT strongly and may thus inhibit the activity of TvPSAT. The long loop between ß8 and α8 at the opening of the TvPSAT active site cleft compared to other PSATs, suggests that this loop may help control the access of substrates to the TvPSAT active site and thus influences the enzyme kinetics. GENERAL SIGNIFICANCE: Our structural and functional studies have improved our understanding of how PSAT helps this organism persists in the environment.


Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Yoduros/farmacología , Transaminasas/antagonistas & inhibidores , Trichomonas vaginalis/enzimología , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Yoduros/química , Yoduros/metabolismo , Cinética , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad , Transaminasas/química , Transaminasas/aislamiento & purificación , Transaminasas/metabolismo
20.
Indian J Endocrinol Metab ; 19(3): 369-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25932392

RESUMEN

BACKGROUND: Leprosy is a chronic granulomatous disease and affects many internal organs in addition to the skin and peripheral nerves. Endocrine dysfunction is often silent and is often missed in patients of leprosy leading to significant morbidity. We studied the presence of occult endocrine disorders in leprosy patients and compared the same with disease parameters. MATERIALS AND METHODS: We evaluated 40 patients of leprosy (aged 18-70 years, any duration) in this cross-sectional, observational study. All subjects were assessed for pituitary, thyroid, adrenal, gonadal function, and dynamic testing was done when deemed necessary. The participants were divided into two groups: Group 1 (Leprosy, n = 40) and Group 2 (Controls, n = 20) and the data were analyzed with appropriate statistical tests. RESULTS: The study participants (35 males, 5 females) had a mean age of 36.4 ± 11.3 years, and duration of the disease was 2.5 ± 5.5 years. Eleven out of 40 patients showed results consistent with an endocrine disorder, including subclinical hypothyroidism (n = 4), sick euthyroid syndrome (n = 3), growth hormone (GH) deficiency (n = 2), primary hypogonadism (n = 2) and secondary hypogonadism in one patient. One patient had partial hypopituitarism (GH deficiency and secondary hypogonadism) and none of the controls showed any hormonal dysfunction. Testosterone levels showed inverse correlation with the number of skin patches (P = 0.0006). CONCLUSION: Occult endocrine dysfunction is seen in a quarter of patients with leprosy. Thyroid and gonadal axes abnormalities are common, and the severity is more in lepromatous forms of the disease. Further large studies are required to confirm the findings observed in our study.

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