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1.
Mol Biol Rep ; 51(1): 286, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329638

RESUMEN

BACKGROUND: Cellular resistance to cisplatin has been one of the major obstacles in the success of combination therapy for many types of cancers. Emerging evidences suggest that exosomes released by drug resistant tumour cells play significant role in conferring resistance to drug sensitive cells by means of horizontal transfer of genetic materials such as miRNAs. Though exosomal miRNAs have been reported to confer drug resistance, the exact underlying mechanisms are still unclear. METHODS AND RESULTS: In the present study, mature miRNAs secreted differentially by cisplatin resistant and cisplatin sensitive HepG2 cells were profiled and the effect of most significantly lowered miRNA in conferring cisplatin resistance when horizontally transferred, was analysed. we report miR-383 to be present at the lowest levels among the differentially abundant miRNAs expressed in exosomes secreted by cisplatin resistant cells compared to that that of cisplatin sensitive cells. We therefore, checked the effect of ectopic expression of miR-383 in altering cisplatin sensitivity of Hela cells. Drug sensitivity assay and apoptotic assays revealed that miR-383 could sensitise cells to cisplatin by targeting VEGF and its downstream Akt mediated pathway. CONCLUSION: Results presented here provide evidence for the important role of miR-383 in regulating cisplatin sensitivity by modulating VEGF signalling loop upon horizontal transfer across different cell types.


Asunto(s)
Cisplatino , MicroARNs , Humanos , Cisplatino/farmacología , Proteínas Proto-Oncogénicas c-akt/genética , Células HeLa , Factor A de Crecimiento Endotelial Vascular/genética , MicroARNs/genética
2.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35443524

RESUMEN

India witnessed a huge surge in Covid 19 cases in the second wave. There was also an increased presentation of Mucor mycosis cases associated with Covid 19 illness. Severe COVID-19 is a hyper-ferritinemic syndrome, but whether high ferritin is a marker of a severe systemic disease versus a modulator of pathophysiology is not known. Irrespective of its role, high ferritin levels lead to excess intracellular iron that generates reactive oxygen species resulting in tissue damage. There are many theories existing presently to associate the development of Mucor mycosis in Covid 19 patients. The present study is to evaluate the correlation between HbA1c and serum ferritin levels in COVID 19 associated Mucor mycosis and the associated outcomes. MATERIAL: It is prospective observational study. RT-PCR confirmed cases of COVID 19 pneumonia with clinical, microbiological or radiologically confirmed cases of mucor mycosis were selected after obtaining informed consent. Relevant clinical data collected, Serum Hba1c and Ferritin was sent. Data analysis was done using SPSS software. OBSERVATION: Among the 97 patients, 63 (64.9 %) were male and 34 (35.1%) were females, 10 (10.3 %) patients had no comorbidities, 82 (84.5 %) patients had diabetes mellitus, 32 (33.0 %) patients had hypertension and 30 (30.9 %) patients had both diabetes and hypertension. Mean Hba1c among the patients was 10.98 %. Mean serum ferritin level was 929.11 ng/dl. Mean Serum ferritin was significantly lower among survivors (843.8 ng/dl) when compared to non survivors (1150.2 ng/dl) (p= 0.034). CONCLUSION: Serum ferritin is significantly elevated in COVID-19- associated mucor mycosis (CAMCR) cases. The mean Hba1c of 10.98 % suggests a background of poorly controlled diabetes mellitus along with COVID 19 infection is a risk factor for mucor mycosis. Serum ferritin was significantly lower among survivors when compared to non survivors. Increased serum ferritin can be associated with poor prognosis and mortality in COVID-19 associated mucor mycosis.


Asunto(s)
COVID-19 , Diabetes Mellitus , Hipertensión , Diabetes Mellitus/epidemiología , Femenino , Ferritinas , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Mucor/metabolismo , SARS-CoV-2
3.
J Biomol Struct Dyn ; 40(6): 2701-2714, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33146070

RESUMEN

SARS-CoV-2 has become a pandemic causing a serious global health concern. The absence of effective drugs for treatment of the disease has caused its rapid spread on a global scale. Similarly to the SARS-CoV, the SARS-CoV-2 is also involved in a complex interplay with the host cells. This infection is characterized by a diffused alveolar damage consistent with the Acute Respiratory Disease Syndrome (ARDS). To explore the complex mechanisms of the disease at the system level, we used a network medicine tools approach. The protein-protein interactions (PPIs) between the SARS-CoV and the associated human cell proteins are crucial for the viral pathogenesis. Since the cellular entry of SARS-CoV-2 is accomplished by binding of the spike glycoprotein binding domain (RBD) to the human angiotensin-converting enzyme 2 (hACE2), a molecule that can bind to the spike RDB-hACE2 interface could block the virus entry. Here, we performed a virtual screening of 55 compounds to identify potential molecules that can bind to the spike glycoprotein and spike-ACE2 complex interface. It was found that the compound ethyl 1-{3-[(2,4-dichlorobenzyl) carbamoyl]-1-ethyl-6-fluoro-4-oxo-1,4-dihydro-7-quinolinyl}-4-piperidine carboxylate (the S54 ligand) and ethyl 1-{3-[(2,4-dichlorobenzyl) carbamoyl]-1-ethyl-6-fluoro-4-oxo-1,4-dihydro-7-quinolinyl}-4 piperazine carboxylate (the S55 ligand) forms hydrophobic interactions with Tyr41A, Tyr505B and Tyr553B, Leu29A, Phe495B, respectively of the spike glycoprotein, the hotspot residues in the spike glycoprotein RBD-hACE2 binding interface. Furthermore, molecular dynamics simulations and free energy calculations using the MM-GBSA method showed that the S54 ligand is a stronger binder than a known SARS-CoV spike inhibitor SSAA09E3 (N-(9,10-dioxo-9, 10-dihydroanthracen-2-yl) benzamide).Communicated by Ramaswamy H. Sarma.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , Antivirales/química , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Enzima Convertidora de Angiotensina 2/química , COVID-19 , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , SARS-CoV-2/efectos de los fármacos , Glicoproteína de la Espiga del Coronavirus/química
4.
Eur J Med Chem ; 219: 113442, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-33878562

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is becoming dangerous to human beings due to easy transmission mode and leading to the difficult-to-treat situation. The rapid resistance development of MRSA to many approved antibiotics is of major concern. There is a lot of scope to develop novel, efficient, specific, and nontoxic drug candidates to fight against MRSA isolates. The interesting molecular structure and adaptable feature of oxadiazole moiety which are bioisosteres of esters and amides, and these functional groups show improved resistance to esterases mediated hydrolytic cleavage, attracting researchers to develop required novel antibiotics based on oxadiazole core. This review summarizes the developments of oxadiazole-containing derivatives as potent antibacterial agents against multidrug-resistant MRSA strains and discussing the structure-activity relationship (SAR) in various directions. The current survey is the highlight of the present scenario of oxadiazole hybrids on MRSA studies, covering articles published from 2011 to 2020. This collective information may become a good platform to plan and develop new oxadiazole-based small molecule growth inhibitors of MRSA with minimal side effects.


Asunto(s)
Antibacterianos/farmacología , Oxadiazoles/química , Animales , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Diseño de Fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Oxadiazoles/metabolismo , Oxadiazoles/farmacología , Relación Estructura-Actividad
5.
Molecules ; 25(19)2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33008036

RESUMEN

PURPOSE: Curcumin is known for its anticancer and migrastatic activity in various cancers, including breast cancer. Newer curcumin derivatives are being explored to overcome limitations of curcumin like low bioavailability, stability, and side effects due to its higher dose. In this study, the synthesis of ST09, a novel curcumin derivative, and its antiproliferative, cytotoxic, and migrastatic properties have been explored both in vitro and in vivo. METHODS: After ST09 synthesis, anticancer activity was studied by performing standard cytotoxicity assays namely, lactate dehydrogenase (LDH) release assay, 3-(4, 5-dimethylthiazol-2-yl)-2-5-diphenyletrazolium bromide (MTT), and trypan blue exclusion assay. Annexin-FITC, cell cycle analysis using flow cytometry, and Western blotting were performed to elucidate cell death mechanisms. The effect on the inhibition of cell migration was studied by transwell migration assay. An EAC (Ehrlich Ascites carcinoma) induced mouse tumor model was used to study the effect of ST09 on tumor regression. Drug toxicity was measured using aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and flow-cytometry based lymphocyte count. Histological analysis was performed for assessment of any tissue injury post ST09 treatment. RESULTS: ST09 shows an approximate 100-fold higher potency than curcumin, its parent compound, on breast tumor cell lines MCF-7 and MDA-MB231. ST09 arrests the cell cycle in a cell type-specific manner and induces an intrinsic apoptotic pathway both in vitro and in vivo. ST09 inhibits migration by downregulating matrix metalloprotease 1,2 (MMP1,2) and Vimentin. In vivo, ST09 administration led to decreased tumor volume in a mouse allograft model by boosting immunity with no significant drug toxicity. CONCLUSION: ST09 exhibits antiproliferative and cytotoxic activity at nanomolar concentrations. It induces cell death by activation of the intrinsic pathway of apoptosis both in vitro and in vivo. It also inhibits migration and invasion. This study provides evidence that ST09 can potentially be developed as a novel antitumor drug candidate for highly metastatic and aggressive breast cancer.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Movimiento Celular/efectos de los fármacos , Curcumina/análogos & derivados , Curcumina/farmacología , Progresión de la Enfermedad , Neoplasias Mamarias Animales/patología , Aloinjertos/efectos de los fármacos , Animales , Puntos de Control del Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Curcumina/química , Modelos Animales de Enfermedad , Femenino , Humanos , Concentración 50 Inhibidora , Metaloproteinasas de la Matriz/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Pruebas de Toxicidad
6.
ACS Omega ; 4(4): 7903-7910, 2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31459878

RESUMEN

A carbon quantum dot-based carbon paste electrode was fabricated and used for the determination of adrenaline (AD) at the nanomolar level. This fabricated electrode exhibited tremendous electrocatalytic activity for the oxidation of adrenaline in supporting electrolyte (PBS of pH 7.4). Scan rate variation studies with the modified electrode revealed that the overall electrode process was controlled by a diffusion process. A lower detection limit of 6 nM was achieved by chronoamperometry. Interference by biological molecules such as serotonin (5-HT) and ascorbic acid (AA) in the electrochemical oxidation of AD on the fabricated electrode was tested. It was observed that with the modified electrode, the selective determination of AD was possible. Further, with the fabricated electrode, simultaneous analysis of AA, AD, and 5-HT was performed, and it was observed that the overlapped peaks of these analytes on the naked electrode were well resolved into three peaks on the modified electrode. Along with decent sensitivity and selectivity, the electrode also showed higher stability and antifouling nature. The real-time application of the projected scheme was proven by employing the said electrode for adrenaline in adrenaline bitartrate injections.

7.
J Phys Condens Matter ; 31(47): 475801, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31342931

RESUMEN

We report here the temperature dependence of electrical resistivity ([Formula: see text](T)), heat capacity (C(T)) and thermal conductivity ([Formula: see text](T)) of superconducting V1-x Ti x alloys in the absence and presence of external applied magnetic fields. The [Formula: see text](T) changes from positive temperature coefficient of resistivity (TCR) to negative TCR at about x = 0.7 indicating that many of these alloys lie close to the Mott-Ioffe-Regel (MIR) limit. The jump in the C(T) across the superconducting transition temperature ([Formula: see text]) indicates that these alloys are in the intermediate coupling limit. The [Formula: see text](T) increases in certain V1-x Ti x alloys as the temperature decreases below the [Formula: see text] indicating that the phonons dominate the heat conduction in the superconducting state, whereas we found that the electrons are the major carriers of heat in the normal state. Our analysis suggests that the unusual features of thermal conductivity have origin in (i) the electron mean free path approaching the inter atomic distances (MIR limit) and (ii) the renormalization of the phonon mean free path due to the presence of point defects and the electron-phonon interaction.

8.
Front Oncol ; 9: 1516, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32010617

RESUMEN

Generally, changes in the metabolic status of cells under conditions like hypoxia and accumulation of lactate can be sensed by various sensing mechanisms, leading to modulation of a number of signal transduction pathways and transcription factors. Several of the proangiogenic cytokines like VEGF, FGF, PDGF, TGF-ß, Ang-2, ILs, etc. are secreted by cancer cells, under hypoxic microenvironment. These cytokines bind to their receptors on the endothelial cells and activates a number of signaling pathways including Akt/PIP3, Src, p38/MAPK, Smad2/3, etc., which ultimately results in the proliferation and migration of endothelial cells. Transcription factors that are activated in response to the metabolic status of tumors include HIFs, NF-κb, p53, El-2, and FOXO. Many of these transcription factors has been reported to be regulated by a class of histone deacetylase called sirtuins. Sirtuins are NAD+ dependent histone deacetylases that play pivotal role in the regulation of tumor cell metabolism, proliferation, migration and angiogenesis. The major function of sirtuins include, deacetylation of histones as well as some non-histone proteins like NF-κB, FOXOs, PPAR⋎, PGC1-α, enzymes like acetyl coenzymeA and structural proteins like α tubulin. In the cell, sirtuins are generally considered as the redox sensors and their activities are dependent on the metabolic status of the cell. Understanding the intricate regulatory mechanisms adopted by sirtuins, is crucial in devising effective therapeutic strategies against angiogenesis, metastasis and tumor progression. Keeping this in mind, the present review focuses on the role of sirtuins in the process of tumor angiogenesis and the regulatory mechanisms employed by them.

9.
ACS Appl Mater Interfaces ; 10(50): 43343-43351, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30465433

RESUMEN

MXene/graphite composite paste electrode (MXene/GCPE)-based electrochemical sensor has been fabricated for the detection of adrenaline. The electrode exhibits a sensitive response to adrenaline in phosphate buffer solution of pH 7.4, and its catalytic activity is much higher than that of the bare graphite paste electrode. The electron-transfer reaction of MXene/GCPE is a diffusion controlled process. The graph of concentration of adrenaline with the peak current exhibits two linearities, one in the lower and other in the higher concentration range with a detection limit of 9.5 nM. The simultaneous analyses of adrenaline, ascorbic acid, and serotonin reveal that the fabricated electrode could separate the overlapped cyclic voltammetric peaks of these ternary mixtures. This electrode has been further employed in the detection of adrenaline in pharmaceutical samples with 99.2-100.8% recoveries.


Asunto(s)
Técnicas Electroquímicas/métodos , Epinefrina/análisis , Grafito/química , Electrodos , Límite de Detección
10.
Front Plant Sci ; 9: 1154, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30158943

RESUMEN

Plants being sessile are under constant threat of multiple abiotic and biotic stresses within its natural habitat. A combined stress involving an abiotic and a biotic factor reportedly increases susceptibility of the plants to pathogens. The emerging threat, collar rot disease of chickpea (caused by Sclerotium rolfsii Sacc.) is reported to be influenced by soil moisture condition (SMC). Hence, we studied the influence of differential SMC viz. upper optimum (100%), optimum (80%), lower optimum (60%), and limiting (40%) soil moisture conditions on colonization and collar rot development over the course of infection in two chickpea cultivars, Annigeri (susceptible to collar rot) and ICCV 05530 (moderately resistant to collar rot). Disease incidence was found to be directly proportional to increase in soil moisture (R2 = 0.794). Maximum incidence was observed at 80% SMC, followed by 100 and 60% SMC. Expression of genes (qPCR analysis) associated with host cell wall binding (lectin) and degradation viz. endopolygalacturonase-2, endoglucosidase, and cellobiohydrolase during collar rot development in chickpea were relatively less at limiting soil moisture condition (40%) as compared to optimum soil moisture condition (80%). As compared to individual stress, the expression of defense response genes in chickpea seedlings were highly up-regulated in seedlings challenged with combined stress. Our qPCR results indicated that the expression of defense-related genes in chickpea during interaction with S. rolfsii at low SMC was primarily responsible for delayed disease reaction. Involvement of moisture and biotic stress-related genes in combined stress showed a tailored defense mechanism.

11.
Ultramicroscopy ; 176: 5-10, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28038784

RESUMEN

We propose an experimental setup based on a streak camera approach inside an energy filter to measure time resolved properties of materials in the transmission electron microscope (TEM). In order to put in place the streak camera, a beam sweeper was built inside an energy filter. After exciting the TEM sample, the beam is swept across the CCD camera of the filter. We describe different parts of the setup at the example of a magnetic measurement. This setup is capable to acquire time resolved diffraction patterns, electron energy loss spectra (EELS) and images with total streaking times in the range between 100ns and 10µs.

12.
Mol Cell Biochem ; 420(1-2): 141-50, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27473146

RESUMEN

Isoxazole derivatives are an important group of chemotherapeutic prototypes. In the current study, we have synthesized few isoxazole derivatives and tested them for their antiproliferative properties in cancer cell lines such as MCF7 and HeLa. The lead compound, 3-(3,4-dimethoxyphenyl)-5-(thiophen-2-yl)isoxazole (2b), showed considerable inhibition of proliferation of MCF7 and HeLa cells with the IC50 values of 19.5 and 39.2 µM, respectively. Cell cycle analyses and annexin-FITC staining in 2b-treated breast adenocarcinoma cells (MCF7) showed increased sub-G1 population and apoptosis. Furthermore, we tested the tumor inhibitory effect of 2b and estrogen receptor expression profile in DMBA-induced mammary tumors in Sprague-Dawley rats. The gross morphology of tumor studies was investigated by histopathology and ERα protein expression was evaluated by immunohistochemistry, which showed tumor regression and downregulation of ERα in tumor cells. The present results implicate that compound 2b could be used for the further derivatization for the treatment of breast cancer.


Asunto(s)
9,10-Dimetil-1,2-benzantraceno/toxicidad , Androstenoles/farmacología , Apoptosis/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Receptor alfa de Estrógeno/biosíntesis , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Mamarias Experimentales , Proteínas de Neoplasias/biosíntesis , Animales , Femenino , Humanos , Células MCF-7 , Neoplasias Mamarias Experimentales/inducido químicamente , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Ratas , Ratas Sprague-Dawley
13.
Phys Med Biol ; 61(4): 1722-37, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26841072

RESUMEN

The irradiation of selective regions in a polymer gel dosimeter results in an increase in optical density and refractive index (RI) at those regions. An optical tomography-based dosimeter depends on rayline path through the dosimeter to estimate and reconstruct the dose distribution. The refraction of light passing through a dose region results in artefacts in the reconstructed images. These refraction errors are dependant on the scanning geometry and collection optics. We developed a fully 3D image reconstruction algorithm, algebraic reconstruction technique-refraction correction (ART-rc) that corrects for the refractive index mismatches present in a gel dosimeter scanner not only at the boundary, but also for any rayline refraction due to multiple dose regions inside the dosimeter. In this study, simulation and experimental studies have been carried out to reconstruct a 3D dose volume using 2D CCD measurements taken for various views. The study also focuses on the effectiveness of using different refractive-index matching media surrounding the gel dosimeter. Since the optical density is assumed to be low for a dosimeter, the filtered backprojection is routinely used for reconstruction. We carry out the reconstructions using conventional algebraic reconstruction (ART) and refractive index corrected ART (ART-rc) algorithms. The reconstructions based on FDK algorithm for cone-beam tomography has also been carried out for comparison. Line scanners and point detectors, are used to obtain reconstructions plane by plane. The rays passing through dose region with a RI mismatch does not reach the detector in the same plane depending on the angle of incidence and RI. In the fully 3D scanning setup using 2D array detectors, light rays that undergo refraction are still collected and hence can still be accounted for in the reconstruction algorithm. It is found that, for the central region of the dosimeter, the usable radius using ART-rc algorithm with water as RI matched medium is 71.8%, an increase of 6.4% compared to that achieved using conventional ART algorithm. Smaller diameter dosimeters are scanned with dry air scanning by using a wide-angle lens that collects refracted light. The images reconstructed using cone beam geometry is seen to deteriorate in some planes as those regions are not scanned. Refraction correction is important and needs to be taken in to consideration to achieve quantitatively accurate dose reconstructions. Refraction modeling is crucial in array based scanners as it is not possible to identify refracted rays in the sinogram space.


Asunto(s)
Algoritmos , Imagenología Tridimensional/métodos , Radiometría/métodos , Tomografía Óptica/métodos , Radiometría/normas , Refractometría
14.
Korean Circulation Journal ; : 499-506, 2016.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-227803

RESUMEN

BACKGROUND AND OBJECTIVES: We assessed plaque erosion of culprit lesions in patients with acute coronary syndrome in real world practice. SUBJECTS AND METHODS: Culprit lesion plaque rupture or plaque erosion was diagnosed with optical coherence tomography (OCT). Intravascular ultrasound (IVUS) was used to determine arterial remodeling. Positive remodeling was defined as a remodeling index (lesion/reference EEM [external elastic membrane area) >1.05. RESULTS: A total of 90 patients who had plaque rupture showing fibrous-cap discontinuity and ruptured cavity were enrolled. 36 patients showed definite OCT-plaque erosion, while 7 patients had probable OCT-plaque erosion. Overall, 26% (11/43) of definite/probable plaque erosion had non-ST elevation myocardial infarction (NSTEMI) while 35% (15/43) had ST elevation myocardial infarction (STEMI). Conversely, 14.5% (13/90) of plaque rupture had NSTEMI while 71% (64/90) had STEMI (p<0.0001). Among plaque erosion, white thrombus was seen in 55.8% (24/43) of patients and red thrombus in 27.9% (12/43) of patients. Compared to plaque erosion, plaque rupture more often showed positive remodeling (p=0.003) with a larger necrotic core area examined by virtual histology (VH)-IVUS, while negative remodeling was prominent in plaque erosion. Overall, 65% 28/43 of plaque erosions were located in the proximal 30 mm of a culprit vessel-similar to plaque ruptures (72%, 65/90, p=0.29). CONCLUSION: Although most of plaque erosions show nearly normal coronary angiogram, modest plaque burden with negative remodeling and an uncommon fibroatheroma might be the nature of plaque erosion. Multimodality intravascular imaging with OCT and VH-IVUS showed fundamentally different pathoanatomic substrates underlying plaque rupture and erosion.


Asunto(s)
Humanos , Síndrome Coronario Agudo , Membranas , Infarto del Miocardio , Placa Aterosclerótica , Rotura , Trombosis , Tomografía de Coherencia Óptica , Ultrasonografía
15.
Biochemistry ; 54(41): 6352-6, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26371545

RESUMEN

A simple method was employed for the synthesis of green luminescent carbon quantum dots (CQDs) from styrene soot. The CQDs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared, and Raman spectroscopy. The prepared carbon quantum dots did not show cellular toxicity and could successfully be used for labeling cells. We also evaluated the effects of carbon quantum dots on the process of angiogenesis. Results of a chorioallantoic membrane (CAM) assay revealed the significant decrease in the density of branched vessels after their treatment with CQDs. Further application of CQDs significantly downregulated the expression levels of pro-angiogenic growth factors like VEGF and FGF. Expression of VEGFR2 and levels of hemoglobin were also significantly lower in CAMs treated with CQDs, indicating that the CQDs inhibit angiogenesis. Data presented here also show that CQDs can selectively target cancer cells and therefore hold potential in the field of cancer therapy.


Asunto(s)
Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacología , Carbono/química , Carbono/farmacología , Puntos Cuánticos/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Factores de Crecimiento de Fibroblastos/genética , Humanos , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Factor A de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
16.
Med Phys ; 42(2): 750-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25652489

RESUMEN

PURPOSE: Proposing an image reconstruction technique, algebraic reconstruction technique-refraction correction (ART-rc). The proposed method takes care of refractive index mismatches present in gel dosimeter scanner at the boundary, and also corrects for the interior ray refraction. Polymer gel dosimeters with high dose regions have higher refractive index and optical density compared to the background medium, these changes in refractive index at high dose results in interior ray bending. METHODS: The inclusion of the effects of refraction is an important step in reconstruction of optical density in gel dosimeters. The proposed ray tracing algorithm models the interior multiple refraction at the inhomogeneities. Jacob's ray tracing algorithm has been modified to calculate the pathlengths of the ray that traverses through the higher dose regions. The algorithm computes the length of the ray in each pixel along its path and is used as the weight matrix. Algebraic reconstruction technique and pixel based reconstruction algorithms are used for solving the reconstruction problem. The proposed method is tested with numerical phantoms for various noise levels. The experimental dosimetric results are also presented. RESULTS: The results show that the proposed scheme ART-rc is able to reconstruct optical density inside the dosimeter better than the results obtained using filtered backprojection and conventional algebraic reconstruction approaches. The quantitative improvement using ART-rc is evaluated using gamma-index. The refraction errors due to regions of different refractive indices are discussed. The effects of modeling of interior refraction in the dose region are presented. CONCLUSIONS: The errors propagated due to multiple refraction effects have been modeled and the improvements in reconstruction using proposed model is presented. The refractive index of the dosimeter has a mismatch with the surrounding medium (for dry air or water scanning). The algorithm reconstructs the dose profiles by estimating refractive indices of multiple inhomogeneities having different refractive indices and optical densities embedded in the dosimeter. This is achieved by tracking the path of the ray that traverses through the dosimeter. Extensive simulation studies have been carried out and results are found to be matching that of experimental results.


Asunto(s)
Fenómenos Ópticos , Polímeros/química , Radiometría/métodos , Tomografía Computarizada por Rayos X , Algoritmos , Geles , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Dosis de Radiación , Relación Señal-Ruido
17.
J Clin Diagn Res ; 7(2): 296-301, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23542767

RESUMEN

INTRODUCTION: Peripheral insensate neuropathy is one of the most commonest and the earliest forms of peripheral neuropathy. It is one of the leading causes of the disability in working population who are at risk. METHODS: A study was conducted in Kasturba medical college (Manipal university) in the year 2009-12, which included examination of 818 people of more than 30yrs of age by random sampling method who were attending the outpatient clinic. A monofilament was used to determine the peripheral insensate neuropathy, which was defined by the presence of one or more insensate areas. RESULTS: In our study , the prevalence of peripheral insensate neuropathy was 16.2 % ( p-0.0001), among which 9.7% were males and 7.5% were females. The males were 1.27 times significantly at a higher risk than the females , even after a height adjustment to the gender difference in height. As the height increased, the prevalence of peripheral insensate neuropathy increased, irrespective of the diabetic and hypertensive statuses. The risk of the peripheral insensate neuropathy increases at a height of >167 cm in males and at a height of >159 cm in females. CONCLUSION: The authors conclude that body height is an important and an independent risk factor for peripheral insensate neuropathy, irrespective of co morbidities. Height as a marker, helps the health care professionals in identifying the people who are at risk for peripheral insensate neuropathy.

18.
J Clin Diagn Res ; 7(2): 326-30, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23543639

RESUMEN

BACKGROUND AND OBJECTIVES: A significant number of women experience perineal trauma following vaginal deliveries and they require stitches. This may result in perineal pain, dyspareunia and faulty healing. The type of suture material which is used, will influence these factors. This study was conducted to compare the impact of two absorbable suture materials which were used for episiotomy repair, namely vicryl rapide and chromic catgut in relation to a short term maternal morbidity, in terms of the perineal pain and the wound healing. METHODS: This was a prospective, randomized study which was conducted in the hospitals which were attached to JJMMC, Davangere. Four hundred women with episiotomies were randomly allocated to repair with either vicrylrapide or chromic catgut (200 each). The outcome measures which were assessed were perineal pain and wound healing at 24-48 hours, 3-5 days and 6 weeks postpartum. RESULTS: The two groups were similar at the trial entry. As compared to the chromic catgut group, the vicryl rapide group was associated with less pain (32.5% vs 57%) and a less need for analgesia (15.5% vs 0.5) at 3-5 days. There was also a signifi- cant reduction in the wound indurations, uncomfortable stitches and wound dehiscence (4% vs 13.5%) and a better wound healing (p<0.05 significant) in the vicrylrapide group. No significant difference was noted in the perineal pain at 6 weeks postpartum. Wound infections (3.5%) and wound resuturing (2%) were seen in the chromic catgut group and they were absent in the vicrylrapide group. INTERPRETATION AND CONCLUSION: So, this study concluded that vicrylrapide was the ideal suture material for episiotomy repair, which resulted in less perineal pain and a better wound healing.

19.
Lett Appl Microbiol ; 46(6): 643-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18384525

RESUMEN

AIM: This work is aimed at optimizing the production of a new heteropolysaccharide (HePS) of Leuconostoc sp. CFR-2181 by standardizing the fermentation conditions in a low cost semi-synthetic medium. METHODS AND RESULTS: Both nutritional and cultural parameters, such as carbon source and its concentration, initial pH of the exopolysaccharide (EPS) medium, fermentation temperature and fermentation period were optimized. Fermentation of the EPS medium (pH 6.7), containing sucrose at 5% (w/v) and 5% (v/v) inoculum, at 25 degrees C resulted in maximum production of HePS (18.38 g l(-1)) by the isolate in 4 h of fermentation. CONCLUSIONS: The isolate was found to produce good amount of HePS in just 4 h in a low cost semi-synthetic EPS medium. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on rapid production of HePS by any lactic culture, which can significantly reduce the cost of the EPS.


Asunto(s)
Microbiología Industrial/métodos , Leuconostoc/metabolismo , Polisacáridos Bacterianos/biosíntesis , Fermentación , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Microbiología Industrial/economía , Cinética , Leuconostoc/clasificación , Sacarosa/metabolismo , Temperatura , Factores de Tiempo
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