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INTRODUCTION: Cirrhotic patients are at a higher risk for sustaining orthopedic fractures with a reported prevalence of 5% to 20%. Cirrhosis also affects wound healing and bleeding risk, and hence, impacts the postoperative outcomes after fracture repair. However, there is limited data available on the postoperative risk factors and clinical outcomes of fractures in patients with chronic liver disease (CLD). METHODS: Data from the National Inpatient Sample for the years 2012 to 2015 were analyzed. Patients were identified using ICD-9 codes for any fracture. ICD-9 codes for CLD were used to categorize patients into CLD and non-CLD groups. Primary outcomes included inpatient mortality, length of stay (LOS), and total hospital charges. Secondary outcomes included complications such as postoperative infection, prosthetic failure, bleeding, and improper wound healing. RESULTS: A total of 931,193 patient encounters for orthopedic fractures were identified and divided into 17,388 with CLD and 913,806 without CLD (non-CLD). The inpatient mortality in patients with CLD was almost twice that of non-CLD patients (odds ratio, 1.95; 95% confidence interval, 1.8-2.1). Patients with CLD also had a longer mean LOS at 7.4±8.6 days versus 5.6±7.2 days (P<0.001) and higher total hospital charges at $76,198±99,494 versus $64,294±95,673 (P<0.001). CLD patients also had higher rates of infections, improper wound healing, and bleeding. DISCUSSION: In this large retrospective study, CLD patients with fractures had significantly higher mortality, LOS and hospital charges. These findings correlate with the higher rates of infection, bleeding, and poorer wound healing in this population. Increased clinician awareness of these risks is a key to improving the care of CLD patients.
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Fracturas Óseas/cirugía , Hepatopatías/complicaciones , Complicaciones Posoperatorias/epidemiología , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Femenino , Precios de Hospital , Humanos , Pacientes Internos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Cicatrización de Heridas/fisiologíaRESUMEN
BACKGROUND: Multidrug resistance-associated protein 1 (MRP1) overexpression plays a major role in chemoresistance in glioblastoma multiforme (GBM) contributing to its notorious deadly nature. Although MRP1-siRNA transfection to GBM in vitro has been shown to sensitise the cells to drug, MRP1 silencing in vivo and the phenotypic influence on the tumour and normal tissues upon MRP1 down-regulation have not been established. Here, porous silicon nanoparticles (pSiNPs) that enable high-capacity loading and delivery of siRNA are applied in vitro and in vivo. RESULT: We established pSiNPs with polyethyleneimine (PEI) capping that enables high-capacity loading of siRNA (92 µg of siRNA/mg PEI-pSiNPs), and optimised release profile (70% released between 24 and 48 h). These pSiNPs are biocompatible, and demonstrate cellular uptake and effective knockdown of MRP1 expression in GBM by 30%. Also, siRNA delivery was found to significantly reduce GBM proliferation as an associated effect. This effect is likely mediated by the attenuation of MRP1 transmembrane transport, followed by cell cycle arrest. MRP1 silencing in GBM tumour using MRP1-siRNA loaded pSiNPs was demonstrated in mice (82% reduction at the protein level 48 h post-injection), and it also produced antiproliferative effect in GBM by reducing the population of proliferative cells. These results indicate that in vitro observations are translatable in vivo. No histopathological signs of acute damage were observed in other MRP1-expressing organs despite collateral downregulations. CONCLUSIONS: This study proposes the potential of efficient MRP1-siRNA delivery by using PEI-capped pSiNPs in achieving a dual therapeutic role of directly attenuating the growth of GBM while sensitising residual tumour cells to the effects of chemotherapy post-resection.
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Silenciador del Gen , Glioblastoma/patología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Nanopartículas/química , Polietileneimina/química , ARN Interferente Pequeño/administración & dosificación , Silicio/química , Animales , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Ratones Desnudos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Nanopartículas/ultraestructura , Especificidad de Órganos , Fenotipo , Porosidad , Propionatos/farmacología , Quinolinas/farmacologíaRESUMEN
The occurrence of resistant bacteria to specific heavy metals can be associated with increasing load of the metals in the environment. River Yamuna is polluted by various toxic heavy metals discharged by several industrial and agricultural sources. Therefore, the use of heavy metal-resistant bacteria as an indicator of metal pollution was tested in the present study. For the purpose of the study, the heavy metal resistance status of 42 Escherichia coli strains isolated from River Yamuna water from 7 sampling sites within a span of 2 years was determined using growth curves and plate dilution method in terms of minimum inhibitory concentration (MIC) values by comparing with MIC value of control strain. Seasonally, the lowest mean MIC value was observed for bacterial strains isolated in post-monsoon (December) 2013 and highest mean MIC value was observed for bacterial strains isolated in monsoon (August) 2015. Site-wise analysis of the maximum mean MIC values for all the isolated strains showed the highest mean Ni MIC value for the bacterial strains isolated from site S4 (ITO), highest mean Cu MIC, Cr MIC, and Fe MIC values for the bacterial strains isolated from site S2 (Najafgarh drain intermixing zone) and highest mean Cd MIC, Pb MIC, and Zn MIC values for the bacterial strains isolated from site S7 (Shahdara drain intermixing zone). Correlation analysis between mean MIC site-wise results with mean heavy metal site-wise concentrations showed significant positive correlation indicating that the higher the mean concentration of a given heavy metal at a given site, the higher the mean MIC value for the strains isolated from the same site indicating higher level of resistance. Overall, the present study has shown that the presence of heavy metals in River Yamuna caused due to indiscriminate discharge of various effluents from different kind of sources as well as due to insufficient treatment capacity of sewage treatment plants as well as common effluent treatment plants, has serious impacts on its bacterial microflora as it leads to the development of resistant strains.
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Monitoreo del Ambiente/métodos , Escherichia coli/aislamiento & purificación , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Agricultura , India , RíosRESUMEN
This investigation delves into the complex interaction at metal-semiconductor interfaces, highlighting the magnetic proximity effect in Ni/Si interfaces through systematic X-ray magnetic circular dichroism (XMCD) studies at Ni and Si edges. We analyzed two Ni/Si heterostructures with differing semiconductor doping, uncovering a magnetic proximity effect manifesting as equilibrium magnetization in the semiconductor substrate induced by the adjacent Ni layer. Our results display distinct magnetization signs corresponding to the doping levels: low-doped samples show parallel alignment to the Ni layer, while high-doped samples align antiparallel, indicating a nuanced interplay of underlying magnetization mechanisms. These findings pinpoint the roles of electron tunneling and exchange splitting modification in the magnetization behavior. The study enriches the understanding of ferromagnetic-semiconductor interface behavior, setting a precedent for the design of advanced spintronic devices that leverage the nuanced magnetic properties of these hybrid systems.
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Previously, we have shown that a combination of metabolic modifiers 2-deoxy-D-glucose (2-DG) and 6-aminonicotinamide (6-AN) results in oxidative stress mediated radiosensitization of malignant cells via mitochondrial dysfunction and non-coordinated expression of antioxidant defense, besides inhibition of repair and recovery. In the present study, our objective was to study, in a panel of human malignant cells of various origins (lung carcinoma, squamous carcinoma, oral carcinoma, and glioblastoma), if the inhibitory activity of combination (2-DG+6-AN+2 Gy) against tumor growth could be considered a general phenomenon and to determine its effect on the cell cycle. The results revealed that combination (2-DG+6-AN+2 Gy) treatment result in significant cell growth inhibition and induced ROS generation in all cancer cells studied. The anti-proliferative effect was related to the ability of combination (2-DG+6-AN+2 Gy) to provoke growth inhibition at the G2/M arrest and apoptosis. Furthermore, combination (2-DG+6-AN+2 Gy) induced G2/M arrest is closely correlated to decreased cyclin A, cyclin B1, and cdc2 levels.
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6-Aminonicotinamida/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Desoxiglucosa/farmacología , Apoptosis/efectos de la radiación , Western Blotting , Proteína Quinasa CDC2 , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Puntos de Control del Ciclo Celular/efectos de la radiación , División Celular/efectos de los fármacos , División Celular/efectos de la radiación , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Quimioradioterapia , Ciclina A/metabolismo , Ciclina B/metabolismo , Quinasas Ciclina-Dependientes , Citometría de Flujo , Fase G2/efectos de los fármacos , Fase G2/efectos de la radiación , Humanos , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The scope of this paper is to outline the main marks and performances of the MagneDyn beamline, which was designed and built to perform ultrafast magnetodynamic studies in solids. Open to users since 2019, MagneDyn operates with variable circular and linear polarized femtosecond pulses delivered by the externally laser-seeded FERMI free-electron laser (FEL). The very high degree of polarization, the high pulse-to-pulse stability, and the photon energy tunability in the 50-300 eV range allow performing advanced time-resolved magnetic dichroic experiments at the K-edge of light elements, e.g., carbon and at the M- and N-edge of the 3d-transition-metals and rare earth elements, respectively. To this end, two experimental end-stations are available. The first is equipped with an in situ dedicated electromagnet, a cryostat, and an extreme ultraviolet Wollaston-like polarimeter. The second, designed for carry-in user instruments, hosts also a spectrometer for pump-probe resonant x-ray emission and inelastic spectroscopy experiments with a sub-eV energy resolution. A Kirkpatrick-Baez active optics system provides a minimum focus of â¼20×20µm2 FWHM at the sample. A pump laser setup, synchronized with the FEL-laser seeding system, delivers sub-picosecond pulses with photon energies ranging from the mid-IR to near-UV for optical pump-FEL probe experiments with a minimal pump-probe jitter of few femtoseconds. The overall combination of these features renders MagneDyn a unique state-of-the-art tool for studying ultrafast magnetic and resonant emission phenomena in solids.
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Oxidative stress-mediated mitochondrial dysfunction is known to induce intrinsic pathway of apoptosis. Previously, we have shown that a combination of metabolic modifiers 2-deoxy-D-glucose (2-DG) and 6-aminonicotinamide (6-AN) results in oxidative stress-mediated radiosensitization of malignant cells via noncoordinated expression of antioxidant defense. We now show that the combination (2-DG + 6-AN + 2Gy) induces significant alterations in mitochondrial membrane potential and oxidative damage to lipid and proteins selectively in malignant cells resulting in the release of cytochrome c from mitochondria and increase in Bax/Bcl-2 ratio stimulating intrinsic pathway of apoptosis, besides enhancing the mitotic death linked to cytogenetic damage. These results highlight the role of mitochondrial dysfunction in selective radiosensitization by 2-DG + 6-AN, besides inhibition of energy-linked DNA repair processes and generation of oxidative stress reported earlier.
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6-Aminonicotinamida/farmacología , Desoxiglucosa/farmacología , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fármacos Sensibilizantes a Radiaciones/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Western Blotting , Línea Celular Tumoral , Rayos gamma/efectos adversos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de la radiación , Mitocondrias/efectos de la radiación , Estrés Oxidativo/efectos de la radiaciónRESUMEN
Functional chest pain, functional heartburn, and reflux hypersensitivity are 3 functional esophageal disorders defined by the Rome IV criteria. Specific criteria, combining symptoms and the results of objective testing, allow for an accurate diagnosis of these conditions. Management may include medications targeted at optimizing acid suppression or neuromodulation, as well as a host of complementary or alternative treatment options. Psychological and behavioral interventions, such as cognitive behavioral therapy and hypnotherapy, have displayed substantial benefits in the treatment of functional chest pain and functional heartburn. Acid suppression and focused neuromodulation are key evidence-based treatment options for reflux hypersensitivity.
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Enfermedades del Esófago , Reflujo Gastroesofágico , Dolor en el Pecho/etiología , Dolor en el Pecho/terapia , Monitorización del pH Esofágico , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/terapia , Pirosis/diagnóstico , Pirosis/etiología , Pirosis/terapia , HumanosRESUMEN
BACKGROUND: To date, studies investigating the inflammatory bowel disease (IBD) patient experience with coronavirus disease 2019 (COVID-19) have consistently reported that the observed rate of COVID-19 within this population is similar to the general population. Limited research has suggested that corticosteroid use in the IBD population may be associated with worse COVID-19 outcomes, but it is still yet to be determined if specific IBD-related clinical factors are associated with worse outcomes. Our goal was to describe clinical COVID-19 outcomes for IBD patients and to identify the clinical factors that may be associated with worse outcomes. METHODS: In this retrospective study, we utilized the inpatient database within the largest hospital network in the New York City Metropolitan area to identify all IBD patients with confirmed COVID-19. RESULTS: Of 83 IBD/COVID-19 patients presenting to a hospital network emergency room, 56 were hospitalized. Overall, 19.6% of hospitalized IBD patients died, compared with 22.2% of all hospital system COVID-19 patients during the time period. There was no association between pre-admission corticosteroid use or biologic treatment with a severe course of COVID-19. CONCLUSIONS: In contrast to some prior reports, we did not observe an association of pre-admission corticosteroid use and adverse outcomes. While the mortality rate was high for IBD/COVID-19 patients, it was not greater than that for hospitalized COVID-19 patients generally. Though our results are encouraging, we continue to support the recommendations of the leading gastrointestinal and IBD societies to regard our patients as "at risk", and to observe caution in their care.
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In this paper, we report the existence of defect induced intrinsic room-temperature ferromagnetism (RTFM) in Cu doped ZnO synthesized via a facile sol-gel route. The wurtzite crystal structure of ZnO remained intact up to certain Cu doping concentrations under the present synthesis environment as confirmed by the Rietveld refined X-ray diffraction pattern with the average crystallite size between 35 and 50 nm. Field emission scanning electron microscopy reveals the formation of bullet-like morphologies for pure and Cu doped ZnO. Diffuse reflectance UV-vis shows a decrease in the energy band gap of ZnO on Cu doping. Further, these ZnO samples exhibit strong visible photoluminescence in the region of 500-700 nm associated with defects/vacancies. Near-edge X-ray absorption fine-structure measurements at Zn, Cu L3,2- and O K-edges ruled out the existence of metallic Cu clusters in the synthesized samples (up to 2% doping concentration) supporting the XRD results and providing the evidence of oxygen vacancy mediated ferromagnetism in Cu : ZnO systems. The observed RTFM in Cu doped ZnO nanostructures can be explained by polaronic percolation of bound magnetic polarons formed by oxygen vacancies. Further, extended X-ray absorption fine-structure data at Zn and Cu K-edges provide the local electronic structure information around the absorbing (Zn) atom. The above findings for ZnO nanostructures unwind the cause of magnetism and constitute a significant lift towards realizing spin-related devices and optoelectronic applications.
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Background: Lack of research data is one of the major challenges identified in traditional medicine (TM). Further, there is an urgent need to strengthen and streamline clinical research processes as well as develop research databases in TM. The Clinical Trials Registry-India (CTRI), a free, online primary register of the WHO's International Clinical Trials Registry Platform, undertakes registration of all clinical trials being conducted in India, including TM trials. However, as the CTRI data set items are primarily designed to capture information of interventional trials of the conventional system of medicine, key fields relevant to the TM system are not adequately captured in the CTRI. Aims and Objectives: The current study was conceptualized with the objective to review the type and quality of trials registered in the CTRI as well as identify the specific data set items in CTRI which may be customized as per Ayurveda studies. Materials and methods: The trials registered from July 1, 2018, to March 31, 2020, were analyzed to decipher the kind of research being undertaken in the field of Ayurveda. These trials were manually reviewed independently by two Ayurveda reviewers to gain insights into the discrepancies. Along with these analysis, brainstorming sessions with Ayurveda experts were also held. Results: The fields which were identified and need tweaking and customization were the fields "health condition" and "intervention/comparator agent." Conclusions: These modifications in the CTRI would enable the capture of more effective Ayurveda-specific information which would in turn help to standardize and streamline research practices as well as raise the standard of research.
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Nanoparticle radiosensitization has been demonstrated well to enhance the effects of radiotherapy, motivate the improvement of therapeutic ratios, and decrease morbidity in cancer treatment. A significant challenge exists in optimizing formulations and translation due to insufficient knowledge of the associated mechanisms, which have historically been limited to physical concepts. Here, we investigated a concept for the role of biological mechanisms. The mere presence of gold nanoparticles led to a down-regulation of thymidylate synthase, important for DNA damage repair in the radioresistant S-phase cells. By developing a cross-correlative methodology to reveal probabilistic gold nanoparticle uptake by cell sub-populations and the associated sensitization as a function of the uptake, a number of revealing observations have been achieved. Surprisingly, for low numbers of nanoparticles, a desensitization action was observed. Sensitization was discovered to preferentially impact S-phase cells, in which impairment of the DNA damage response by the homologous recombination pathway dominates. This small but radioresistant cell population correlates with much greater proliferative ability. Thus, a paradigm is presented whereby enhanced DNA damage is not necessarily due to an increase in the number of DNA double-strand breaks (DSBs) created but can be from a nanoparticle-induced impairment of the damage response by down-regulating repair proteins such as thymidylate synthase.
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Nanopartículas/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Análisis de la Célula Individual , Línea Celular Tumoral , Roturas del ADN de Doble Cadena , Regulación hacia Abajo/efectos de los fármacos , Endocitosis/efectos de los fármacos , Oro/química , Histonas/metabolismo , Humanos , Nanopartículas/ultraestructura , Fase S/efectos de los fármacos , Timidilato Sintasa/metabolismoRESUMEN
Chylous ascites (CA) is a rare form of ascites that results from the leakage of lipid-rich lymph into the peritoneal cavity. This usually occurs due to trauma and rupture of the lymphatics or increased peritoneal lymphatic pressure secondary to obstruction. The underlying etiologies for CA have been classified as traumatic, congenital, infectious, neoplastic, postoperative, cirrhotic or cardiogenic. Since malignancy and cirrhosis account for about two-thirds of all the cases of CA in Western countries, in this article we have attempted to reclassify CA based on portal and non-portal etiologies. The diagnosis of CA is based on the distinct characteristic of the ascitic fluid which includes a milky appearance and a triglyceride level of >200 mg/dL. The management consists of identifying and treating the underlying disease process, dietary modification, and diuretics. Some studies have also supported the use of agents such as orlistat, somatostatin, octreotide and etilefrine. Paracentesis and surgical interventions in the form of transjugular intrahepatic portosystemic shunt (commonly known as TIPS), peritoneal shunt, angiography with embolization of a leaking vessel, and laparotomy remain as treatment options for cases refractory to medical management.
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An explicit study of comparison on the basis of structure and electronic properties of ZnO nanostructures was discussed. ZnO synthesized by sol-gel and hydrothermal method without using any surfactant leads to the formation of two different morphologies. Rietveld crystal structure refinement of X-ray diffraction patterns confirmed the wurtzite structure of both samples. Raman spectra also confirmed the wurtzite phase formation and improved crystallinity in sample synthesized by hydrothermal route that are concurrent with results obtained from X-ray diffraction. Field-emission scanning electron microscopy revealed the formation of ZnO spherical nanoparticle structure for sol-gel method and flower like µ-structure for ZnO prepared through hydrothermal route. Williamson-Hall equations applied to study the strain and stress parameters present in the material, show the decrease in their values as the crystal size increases. Energy band gap is calculated using diffused reflectance spectroscopy. Near-edge X-ray absorption fine-structure measurements at O K- and Zn L3,2- edges simulated with FEFF9.05 code confirmed the presence of oxygen vacancies. Further extended x-ray absorption fine-structure revealed a similar local atomic structure for both samples despite having different morphologies.
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Gastrointestinal (GI) metastasis from primary lung cancer is a rare clinical finding. Lung cancer most often metastasizes to the brain, bone, liver, and adrenal glands; with gastrointestinal involvement being very rare. We report a case of a 39-year-old female with a diagnosis of poorly differentiated Squamous Cell Carcinoma (SCC) of the lung presenting with dizziness and melena. Esophagogastroduodenoscopy (EGD) showed a bleeding mass in the stomach. Final biopsy report and Immunohistochemistry (IHC) of the specimen were consistent with SCC lung metastasis. While it is imperative to have a high clinical suspicion for GI metastasis in patients with primary lung cancer presenting with GI symptoms, it may be challenging to establish diagnosis. Endoscopy along with pathology and immunohistochemistry play a crucial role in differentiating primary GI malignancies from metastasis.
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Ectopic varices (ECV) occur along the gastrointestinal (GI) tract outside the common variceal sites and represent 2%-5% of all GI variceal bleeds with mortality rates up to 40%. Management is challenging because of inaccessibility and increased risk of rebleeding. We report what is to our knowledge the first clinical use of a new microvascular plug (MVP) with transjugular intrahepatic portosystemic shunt (TIPSS) for a bleeding duodenal varix (DV). A 68-year-old man presented with melena. Endoscopy demonstrated a grade II varix in the second part of the duodenum with red wale sign. TIPSS was performed and portogram revealed a single DV. Poststent placement venogram revealed a persistent varix and hence a 5-7 mm MVP was deployed. Subsequent imaging showed cessation of blood through the DV. The patient had no further bleeding. TIPSS with embolisation is an effective treatment for ECV. This MVP offers advantages due to its size and compatibility and can be redeployed in case of suboptimal placement.
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Duodeno/irrigación sanguínea , Embolización Terapéutica/instrumentación , Várices/diagnóstico , Anciano , Diagnóstico Diferencial , Endoscopía del Sistema Digestivo , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Derivación Portosistémica Intrahepática Transyugular , Várices/complicaciones , Várices/diagnóstico por imagen , Várices/cirugíaRESUMEN
Continuing our research efforts in developing mesoporous silicon nanoparticle-based biomaterials for cancer therapy, we employed here porous silicon nanoparticles as a nanocarrier to deliver contrast agents to diseased cells. Nanoconfinement of small molecule Gd-chelates (L1-Gd) enhanced the T1 contrast dramatically compared to distinct Gd-chelate (L1-Gd) by virtue of its slow tumbling rate, increased number of bound water molecules, and their occupancy time. The newly synthesized Gd-chelate (L1-Gd) was covalently grafted on silicon nanostructures and conjugated to an antibody specific for epidermal growth factor receptor (EGFR) via a hydrazone linkage. The salient feature of this nanosized contrast agent is the capability of EGFR targeted delivery to cancer cells. Mesoporous silicon nanoparticles were chosen as the nanocarrier because of their high porosity, high surface area, and excellent biodegradability. This type of nanosized contrast agent also performs well in high magnetic fields.
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Nanopartículas , Medios de Contraste , Receptores ErbB , Gadolinio , Imagen por Resonancia Magnética , SilicioRESUMEN
It has been universally delineated that the plasmonic metal nanoparticles can enhance the efficiency of photovoltaic cell by increasing the probability of energetic solar photons capturing phenomena using localized surface plasmonic resonance response. In this paper, we developed a novel in-situ simple approach to synthesize noble plasmonic silver nanoparticles (AgNP) from aqueous poly-vinyl-pyrrolidone solution of metal salt using radiolysis of water via synchrotron monochromatic X-ray irradiation without any chemical reducing agent. X-ray irradiation of water produces hydrated electrons (e(-)aq), superoxide (O(-)2) and atom radicals H*, which triggers the reaction and reduces metal salt. X-ray radiolysis based synthesis provides the control over the reaction and prevent the formation of secondary products as occurs in case of chemical reduction route. In the previous studies, synchrotron "white" X-rays had been examined for the synthesis of metal nanoparticles, but that technique limits only upto the material synthesis while in this work we explored the role of "monochromatic" X-rays for the production of bulk amount of nanoparticles which would also provide the feasibility of in-situ characterization. Transmission electron micrographs show that the synthesized AgNP appears spherical with diameter of 2-6 nm and is in agreement with the size estimation from uv-vis spectra by "Mie theory".
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Our earlier studies have shown that simultaneous inhibition of glycolysis and pentose phosphate pathway using 2-deoxy-d-glucose (2-DG, an inhibitor of glycolysis) and 6-aminonicotinamide (6-AN, an inhibitor of pentose phosphate pathway) lead to metabolic oxidative stress (MOS), resulting in radiosensitization in malignant cells. Present study was carried out to investigate the effects of 2-DG and 6-AN on intricately regulated endogenous antioxidant defense against MOS during radiosensitization by this combination. Two human tumor cell lines {Head and Neck Squamous carcinoma (KB) and Glioma (BMG-1)} and one non-malignantly transformed cell line (human embryonic kidney, HEK) were used in this study. The presence of 2-DG and 6-AN (added just before irradiation) for 4h, significantly decreased the clonogenicity and metabolic viability of KB and BMG-1 cell lines, while no significant change was seen in HEK cells. Accumulation of ROS was observed only in malignant cell lines, which displayed a compromised redox status evident from enhanced NADP(+)/NADPH and GSSG/GSH ratios and a concomitant decrease in glutathione reductase level and activity at 24h following treatment. The levels and activities of Cu, Zn-SOD and Mn-SOD increased with MOS and were accompanied by a decreased GPx and unaltered catalase activity and level. These results suggest that non-coordinated expression of antioxidant defense, besides compromised redox status, led to selective radiosensitization in the malignant cells.