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1.
J Liposome Res ; : 1-18, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38591935

RESUMEN

The clinical use of selegiline hydrochloride in conventional dosage forms is to reduce the progression of Parkinson's disease (PD). However, its limited access to the brain, short half-life, and first-pass metabolism minimize brain uptake. Nano-based liposomes offer promising tools for brain-targeted delivery of therapeutics, especially intranasally administered cationic liposomes that target the brain region via the olfactory route and reduce biodistribution. In the present work, cationic liposomes encapsulated with selegiline hydrochloride were fabricated for intranasal administration against PD. The liposomes were initially optimized by Box Behnken design, and the selected run was coated with stearylamine to provide a cationic charge to the liposomes. The final coated liposomes, SH-LP3, demonstrated a minimum size of 173 ± 2.13 nm, an ideal zeta potential of +16 ± 1.98, and achieved a maximum entrapment efficiency of 40.14 ± 1.83%. Morphology analysis showed the spherical shape of liposomes in the size range of 100-200 nm. The in vitro cytotoxicity assay in SHSY5Y cell lines showed a significant decrease in toxicity, almost ten times less, compared to pure selegiline hydrochloride. Animal studies on rotenone-lesioned C57BL6 mice model for PD were performed to investigate the effect of intranasally administered liposomes. The SH-LP3 formulation exhibited remarkable effectiveness in relieving symptoms of PD. This extensive analysis emphasizes the possibility of intranasally administered SH-LP3 liposomes as a feasible treatment option for PD. The formulation not only delivers continuous drug release but also displays better safety and efficacy, providing a platform for additional studies and growth in the domain of PD treatment.

2.
J Biomol Struct Dyn ; : 1-17, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37948295

RESUMEN

F. carica is a small tree and commonly used as a traditional medicine against several disorders. Diabetes is currently treated with insulin and oral hypoglycemic medicines such as sulphonyl urea derivatives, bigunides, thiazolidinediones and alpha-glucosidase inhibitors. Peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists were found to be very much beneficial in the management of diabetes by inhibiting hepatic gluconeogenesis. The aim of this study is to evaluate the bioactive phytoconstituents from Ficus carica Linn. against the target PPAR-γ agonist by in silico docking approach. We investigated 68 phytoconstituents as potential inhibitors of PPAR-γ agonists and the top 24 phytoconstituents were further selected for molecular docking studies. Drug ability, side effects, and ADMET analysis were determined by using MolSoft, toxtree freeware, and ADMET SAR web server, respectively. The phytoconstituents were docked with the target PPAR-γ (PDB ID: 4Y29, 1.98 Å) receptor. Quercetin-3-o-rutinoside possessed the highest G score -14.22 kcal/mol, followed by Angelicin with a G score of -13.56 kcal/mol. All the other phytoconstituents displayed good pharmacokinetic and toxicological parameters with values within the permissible limits. The ligand-protein interaction was calculated by molecular dynamic (MD) simulation study. Subsequently, the binding free energy of the Quercetin-3-o-rutinosideand Pioglitazone complex was calculated using MMPBSA analysis. The results indicated that some of the phytoconstituents from Ficus carica have potency as an anti-diabetic agents. So, these bioactive phytoconstituents like Quercetin-3-o-glucoside, 5-O-caffeoylquinic acids may act as a good agonist for PPAR-γ.Communicated by Ramaswamy H. Sarma.

3.
Curr Drug Res Rev ; 15(1): 88-100, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36017854

RESUMEN

BACKGROUND: Breast cancer is the most commonly diagnosed and major cause of cancer-related deaths in women worldwide. Disruption of the normal regulation of cell cycle progression and proliferation are the major events leading to cancer. Human Polo-like Kinase 1 (PLK1) plays an important role in the regulation of cellular division. High PLK1 expression is observed in various types of cancer including breast cancer. 1,3,4-oxadiazoles are the fivemembered heterocycles, that serve as versatile lead molecules for designing novel anticancer agents and they mainly act by inhibiting various enzymes and kinases. OBJECTIVE: A novel series of 1,3,4-oxadiazole derivatives (A1-A26) were designed and subjected to an in-silico analysis against PLK1 enzyme (PDB ID:1q4k), targeting breast cancer. METHODS: The chemical structure of each compound (A1-26) was drawn using ChemDraw software. The 3D structure model of protein target (PDB ID:1q4k) was built using the SWISSMODEL server. Molecular docking simulation was performed to determine the designed compound's probable binding mode and affinity towards the protein target (PDB ID:1q4k). The designed compounds were subjected to ADME screening, as well as Prime MM/GBSA simulations using Schrodinger suite 2020-4. Furthermore, the safety profile of compounds was examined through the OSIRIS property explorer program and the results were compared with the standard drugs, 5-fluorouracil and cyclophosphamide. RESULTS: Based on the binding affinity scores, the compounds were found selective to target protein 1q4k through hydrogen bonding and hydrophobic interactions. The compounds A11, A12, and A13 were found to have higher G scores and binding free energy values. The ADME screening results were also found to be within the acceptable range. Moreover, the in-silico toxicity prediction assessments suggest that all designed compounds have a low risk of toxicity, and have higher efficiency for the target receptor. CONCLUSION: The study showed that the substitution of electron-donating groups at the various position of the aromatic ring, which is bonded at the second position of the substituted 1,3,4- oxadiazole nucleus resulted in compounds with good binding energy and G score compared to the standard drugs, and hence, they can be further developed as potent PLK1 enzyme inhibitors.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Femenino , Humanos , Simulación del Acoplamiento Molecular , Oxadiazoles/farmacología , Oxadiazoles/química , Antineoplásicos/farmacología , Antineoplásicos/química , Simulación de Dinámica Molecular
4.
Phys Rev Lett ; 128(8): 081803, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275651

RESUMEN

One of the outstanding problems in physics is to explain the baryon-antibaryon asymmetry observed in nature. According to the well-known Sakharov criterion for explaining the observed asymmetry, it is essential that CP violation exist. Even though CP violation has been observed in meson decays and is an integral part of the standard model (SM), measurements in meson decays indicate that CP violation in the SM is insufficient to explain the observed baryon-antibaryon asymmetry. The SM predicts the existence of yet to be observed CP violation in baryon decays. A critical test of the SM requires that CP violation be measured in baryon decays as well, in order to verify that it agrees with the measurement using meson decays. In this Letter we propose a new method to measure the CP violating phase in b baryons, using interference arising implicitly due to Bose symmetry considerations of the decaying amplitudes.

5.
Sci Rep ; 9(1): 5160, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30914713

RESUMEN

This study probes the temperature-dependent strain that is strongly correlated with the orbital and magnetic structures of epitaxial films of Nd0.35Sr0.65MnO3 (NSMO) that are fabricated by pulsed laser deposition with two thicknesses, 17 (NS17) and 103 nm (NS103) on SrTiO3 (STO) substrate. This investigation is probed using X-ray diffraction (XRD) and absorption-based techniques, X-ray linear dichroism (XLD) and the X-ray magnetic circular dichroism (XMCD). XRD indicates a significant shift in the (004) peak position that is associated with larger strain in NS17 relative to that of NS103 at both 30 and 300 K. Experimental and atomic multiplet simulated temperature-dependent Mn L3,2-edge XLD results reveal that the stronger strain in a thinner NS17 film causes less splitting of Mn 3d eg state at low temperature, indicating an enhancement of orbital fluctuations in the band above the Fermi level. This greater Mn 3d orbital fluctuation can be the cause of both the enhanced ferromagnetism (FM) as a result of spin moments and the reduced Néel temperature of C-type antiferromagnetism (AFM) in NS17, leading to the FM coupling of the canted-antiferromagnetism (FM-cAFM) state in NSMO/STO epitaxial films at low temperature (T = 30 K). These findings are also confirmed by Mn L3,2-edge XMCD measurements.

6.
Environ Microbiol ; 18(9): 2810-24, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26769275

RESUMEN

TRAM domain proteins present in Archaea and Bacteria have a ß-barrel shape with anti-parallel ß-sheets that form a nucleic acid binding surface; a structure also present in cold shock proteins (Csps). Aside from protein structures, experimental data defining the function of TRAM domains is lacking. Here, we explore the possible functional properties of a single TRAM domain protein, Ctr3 (cold-responsive TRAM domain protein 3) from the Antarctic archaeon Methanococcoides burtonii that has increased abundance during low temperature growth. Ribonucleic acid (RNA) bound by Ctr3 in vitro was determined using RNA-seq. Ctr3-bound M. burtonii RNA with a preference for transfer (t)RNA and 5S ribosomal RNA, and a potential binding motif was identified. In tRNA, the motif represented the C loop; a region that is conserved in tRNA from all domains of life and appears to be solvent exposed, potentially providing access for Ctr3 to bind. Ctr3 and Csps are structurally similar and are both inferred to function in low temperature translation. The broad representation of single TRAM domain proteins within Archaea compared with their apparent absence in Bacteria, and scarcity of Csps in Archaea but prevalence in Bacteria, suggests they represent distinct evolutionary lineages of functionally equivalent RNA-binding proteins.


Asunto(s)
Proteínas Arqueales/química , Methanosarcinaceae/genética , ARN de Archaea/química , Proteínas de Unión al ARN/química , Regiones Antárticas , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Frío , ARN de Archaea/metabolismo , ARN Ribosómico 5S/química , ARN Ribosómico 5S/metabolismo , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
7.
Indian J Med Microbiol ; 33(2): 231-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25865973

RESUMEN

INTRODUCTION: Class1 integrons are one of the prevalent mechanisms of antibiotic resistance gene transfer in Gram-negative organisms, but their prevalence and role in the spread of antibiotic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) is unexplored. The purpose of this study was to investigate the prevalence of class 1 integrons in clinical isolates of MRSA. MATERIALS AND METHODS: Total 143 MRSA isolates obtained from two different cities in India (Pune and Mumbai) were characterized by biochemical tests, and the antibiotic sensitivity was performed using the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of class 1 integrons, sul1/qacE0Δ1 region of class 1 integron and mecA gene among these isolates was determined by polymerase chain reaction (PCR). RESULTS: All 143 isolates were mecA positive and coagulase-positive. Overall, 71% of the MRSA isolates carried class 1 integrons; 58% (45/77) of the isolates obtained from Mumbai and 85% (56/66) of the isolates from Pune carried class 1 integrons. In all, 39% of these isolates carried sul1/qacEΔ1 region, thus confirming the association of class 1 integrons with antibiotic resistance genes. Along with ß-lactam antibiotics the MRSA isolates were resistant to several other antibiotics, with resistance to erythromycin, ciprofloxacin and trimethoprim-sulfamethoxazole being observed in 75%, 66% and 60% of the isolates, respectively. CONCLUSION: To the best of our knowledge, this is the first report of class 1 integrons in MRSA isolates from India. The study provides insights into the prevalence of a novel mechanism adapted by MRSA for the propagation of antibiotic resistance genes.


Asunto(s)
Integrones , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Ciudades , ADN Bacteriano/genética , Humanos , India/epidemiología , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Prevalencia
8.
Am J Transplant ; 14(9): 2168-72, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25041695

RESUMEN

The impact of kidney donation on the ability to change or initiate health or life insurance following donation is unknown. To quantify this risk, we surveyed 1046 individuals who donated a kidney at our center between 1970 and 2011. Participants were asked whether they changed or initiated health or life insurance after donation, and if they had any difficulty doing so. Among 395 donors who changed or initiated health insurance after donation, 27 (7%) reported difficulty; among those who reported difficulty, 15 were denied altogether, 12 were charged a higher premium and 8 were told they had a preexisting condition because they were kidney donors. Among 186 donors who changed or initiated life insurance after donation, 46 (25%) reported difficulty; among those who reported difficulty, 23 were denied altogether, 27 were charged a higher premium and 17 were told they had a preexisting condition because they were kidney donors. In this single-center study, a high proportion of kidney donors reported difficulty changing or initiating insurance, particularly life insurance. These practices by insurers create unnecessary burden and stress for those choosing to donate and could negatively impact the likelihood of live kidney donation among those considering donation.


Asunto(s)
Seguro de Salud , Riñón , Donadores Vivos , Adulto , Honorarios y Precios , Femenino , Humanos , Seguro de Salud/economía , Masculino
9.
Indian Heart J ; 66(1): 11-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24581090

RESUMEN

BACKGROUND: Drug eluting stents have remarkably improved results of percutaneous coronary angioplasty. Most of the currently available drug eluting stents uses a durable polymer as drug carrier which has been implicated in local inflammatory response and continued incidence of late and very late stent thrombosis. The Pronova XR stent is one from those new generation polymer free sirolimus eluting stents in which pharmaceutical excipient is used for the timed release of sirolimus from the XR stent platform instead of a polymeric coating. METHODOLOGY: We consecutively recruited 121 patients undergoing elective or urgent PCI at our center. All the patients were followed up clinically and mandatory follow up angiogram at 6 months was done for one third of the total patients. An independent core lab analyzed paired angiograms. RESULTS: The primary efficacy endpoint was death, MI, TVR at 6 months which occurred in 6.66% patients. The QCA analysis showed reference vessel diameter of 2.5 + 0.44 mm at baseline and the minimal luminal diameter was 0.88 + 0.43 mm giving baseline diameter stenosis of 65.26 + 15.89%. The immediate post procedure in-segment diameter stenosis assessed was 23.68 + 8.96% which increased to 36.02 + 24.48% at follow up with a late lumen loss of 0.25 + 0.76 mm at mean of 191 days. CONCLUSION: Coronary angioplasty with polymer free Pronova XR stents results in acceptable late lumen loss and very low target lesion revascularisation at short and intermediate term in unselected patients.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Estenosis Coronaria/terapia , Stents Liberadores de Fármacos , Sirolimus/administración & dosificación , Anciano , Angioplastia Coronaria con Balón/métodos , Angioplastia Coronaria con Balón/mortalidad , Estudios de Cohortes , Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/mortalidad , Excipientes/farmacología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Polímeros , Estudios Prospectivos , Diseño de Prótesis , Falla de Prótesis , Medición de Riesgo , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Tasa de Supervivencia , Resultado del Tratamiento
10.
J Assoc Physicians India ; 62(10): 60-3, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25906527

RESUMEN

Vascular malformations are difficult to treat because of poor results of treatment and recurrence of symptoms. Percutaneous and/or transluminal embolisation has refined the treatment of surface vascular lesions; especially with availability of variety of sclerosants.We report a case of a young girl with vascular malformation of right foot, which was treated with percutaneous sclerotherapy with sodium tetradecyl sulphate (STS). Result was excellent and so far the patient is free of her symptoms.


Asunto(s)
Enfermedades del Pie/terapia , Soluciones Esclerosantes/uso terapéutico , Escleroterapia/métodos , Tetradecil Sulfato de Sodio/uso terapéutico , Arterias Tibiales/anomalías , Malformaciones Vasculares/terapia , Adolescente , Femenino , Humanos
12.
Drug Res (Stuttg) ; 63(12): 650-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23904216

RESUMEN

Dimedone derivatives (L1-L4) with methyl substitution at the ortho, para and meta positions were synthesized and their anti-radical, photoreactive and photostability activities were evaluated. All compounds are characterized by spectroscopic techniques and by single crystal X ray diffraction. UV exposure experiments on pBR322 showed inhibition of plasmid DNA fragmentation by UV radiation in a dose dependent manner. Radical scavenging assays and ESR spectra indicate that these compounds possess antiradical activities and do not photodegrade to form other side products as confirmed by chromatographic analysis. They are non-cytotoxic towards human keratinocyte HaCaT cell line indicates their potentiality in sunscreens.


Asunto(s)
Ciclohexanonas/farmacología , Depuradores de Radicales Libres/farmacología , Queratinocitos/efectos de los fármacos , Protectores Solares/farmacología , Línea Celular , Cristalografía por Rayos X , Ciclohexanonas/síntesis química , Ciclohexanonas/química , Fragmentación del ADN/efectos de los fármacos , Fragmentación del ADN/efectos de la radiación , Relación Dosis-Respuesta a Droga , Depuradores de Radicales Libres/síntesis química , Depuradores de Radicales Libres/química , Humanos , Queratinocitos/efectos de la radiación , Plásmidos , Análisis Espectral , Relación Estructura-Actividad , Protectores Solares/síntesis química , Protectores Solares/química
14.
Am J Transplant ; 12(2): 400-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21992578

RESUMEN

Despite the fact that suboptimal kidneys have worse outcomes, differences in waiting times and wait-list mortality have led to variations in the use of these kidneys. It is unknown whether aggressive center-level use of one type of suboptimal graft clusters with aggressive use of other types of suboptimal grafts, and what center characteristics are associated with an overall aggressive phenotype. United Network for Organ Sharing (UNOS) data from 2005 to 2009 for adult kidney transplant recipients was aggregated to the center level. An aggressiveness score was assigned to each center based on usage of suboptimal grafts. Deceased-donor transplant volume correlated with aggressiveness in lower volume, but not higher volume centers. Aggressive centers were mostly found in regions 2 and 9. Aggressiveness was associated with wait-list size (RR 1.69, 95% CI 1.20-2.34, p = 0.002), organ shortage (RR 2.30, 95% CI 1.57-3.37, p < 0.001) and waiting times (RR 1.75, 95% CI 1.20-2.57, p = 0.004). No centers in single-center OPOs were classified as aggressive. In cluster analysis, the most aggressive centers were aggressive in all metrics and vice versa; however, centers with intermediate aggressiveness had phenotypic patterns in their usage of suboptimal kidneys. In conclusion, wait-list size, waiting times, geographic region and OPO competition seem to be driving factors in center-level aggressiveness.


Asunto(s)
Supervivencia de Injerto , Fallo Renal Crónico/cirugía , Trasplante de Riñón/estadística & datos numéricos , Donantes de Tejidos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Listas de Espera , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Retrospectivos , Factores de Tiempo
15.
Am J Transplant ; 11(11): 2388-404, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21794084

RESUMEN

Approximately 50,000 women of reproductive age in the United States are currently living after kidney transplantation (KT), and another 2800 undergo KT each year. Although KT improves reproductive function in women with ESRD, studies of post-KT pregnancies are limited to a few voluntary registry analyses and numerous single-center reports. To obtain more generalizable inferences, we performed a systematic review and meta-analysis of articles published between 2000 and 2010 that reported pregnancy-related outcomes among KT recipients. Of 1343 unique studies, 50 met inclusion criteria, representing 4706 pregnancies in 3570 KT recipients. The overall post-KT live birth rate of 73.5% (95%CI 72.1-74.9) was higher than the general US population (66.7%); similarly, the overall post-KT miscarriage rate of 14.0% (95%CI 12.9-15.1) was lower (17.1%). However, complications of preeclampsia (27.0%, 95%CI 25.2-28.9), gestational diabetes (8.0%, 95%CI 6.7-9.4), Cesarean section (56.9%, 95%CI 54.9-58.9) and preterm delivery (45.6%, 95%CI 43.7-47.5) were higher than the general US population (3.8%, 3.9%, 31.9% and 12.5%, respectively). Pregnancy outcomes were more favorable in studies with lower mean maternal ages; obstetrical complications were higher in studies with shorter mean interval between KT and pregnancy. Although post-KT pregnancy is feasible, complications are relatively high and should be considered in patient counseling and clinical decision making.


Asunto(s)
Trasplante de Riñón , Resultado del Embarazo , Adulto , Cesárea , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Persona de Mediana Edad , Embarazo , Complicaciones del Embarazo/epidemiología
16.
J Pharm Bioallied Sci ; 3(2): 302-5, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21687363

RESUMEN

Herbs have been used for medicinal purposes for centuries. According to recent investigations, they may help reduce the risk of chronic diseases, cardiovascular disease, and cancer due to antioxidant properties, which in turn can be attributed to the various phytoconstituents. With this intention, evaluation of antioxidant activity was performed. Methanol extract of aerial parts of Artemisia pallens Wall was screened for its antioxidant activity due to phenolic and flavonoid contents, by employing radical scavenging assays; 2,2 -diphenyl, 1-picryl hydrazyl (DPPH) and nitric oxide. Ascorbic acid was used as a standard. Quantitative determination of phenols and flavonoids were carried out using spectrophotometric method. Total flavonoid content was determined as quercetin equivalent and total phenolic content was determined as pyrocatechol equivalent using Folin-Ciocalteu reagent. Plant produces more phenolic compounds than flavonoids. IC(50) value of methanol extract for DPPH free radical scavenging activity was found to be 292.7 µg, whereas for nitric oxide it was 204.61 µg. The result obtained in the present study indicates that the aerial parts of this plant are a rich source of natural antioxidants.

17.
J Assoc Physicians India ; 59 Suppl: 31-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22624279

RESUMEN

Recently the reperfusion therapy in the form of Primary Percutaneous Coronary intervention (PPCI) has become the gold standard for the treatment of Acute Myocardial Infarction. In spite of rapid revascularization either with PPCI or thrombolytic therapy, the significant number of patients develops decreased left ventricular function leading to heart failure which can increase long-term mortality and morbidity. The number of strategies are being evolved and evaluated to reduce this post infarct heart failure. They are being developed at the level of optimizing the outcomes of PPCI, protection against the reperfusion injury, and novel therapies like cardiac repair and regeneration and sonothrombolysis. Thrombus aspiration using simple aspiration catheters during PPCI are getting established as a useful adjunct tool to reduce distal embolisation and consequently improving myocardial salvage. The newer antiplatelet drugs like Prasugrel and Ticagrelor may replace the Clopidogrel to reduce ischemic complications. The reduction in reperfusion injury using drugs has shown mixed results. The newer modalities like cardiac repair and regeneration using stem cell therapy looks promising but are yet to be established.


Asunto(s)
Antifibrinolíticos/uso terapéutico , Manejo de la Enfermedad , Infarto del Miocardio/terapia , Reperfusión Miocárdica , Terapia Trombolítica , Humanos , Precondicionamiento Isquémico , Infarto del Miocardio/tratamiento farmacológico , Trasplante de Células Madre , Resultado del Tratamiento
18.
Phys Rev Lett ; 107(27): 271801, 2011 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-22243303

RESUMEN

We present a new method using Dalitz plots and Bose symmetry of pions that allows the complete determination of the magnitudes and phases of weak decay amplitudes. We apply the method to processes such as B→K*π, with the subsequent decay of K*→Kπ. Our approach enables the additional measurement of an isospin amplitude without any theoretical assumption. This advance will help in measuring the weak phase and probing for new physics beyond the standard model with fewer assumptions.

19.
Clin Radiol ; 65(7): 567-81, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20541656

RESUMEN

Targeted contrast-enhanced ultrasound (molecular ultrasound) is an emerging imaging strategy that combines ultrasound technology with novel molecularly-targeted ultrasound contrast agents for assessing biological processes at the molecular level. Molecular ultrasound contrast agents are nano- or micro-sized particles that are targeted to specific molecular markers by adding high-affinity binding ligands onto the surface of the particles. Following intravenous administration, these targeted ultrasound contrast agents accumulate at tissue sites overexpressing specific molecular markers, thereby enhancing the ultrasound imaging signal. High spatial and temporal resolution, real-time imaging, non-invasiveness, relatively low costs, lack of ionising irradiation and wide availability of ultrasound systems are advantages compared to other molecular imaging modalities. In this article we review current concepts and future directions of molecular ultrasound imaging, including different classes of molecular ultrasound contrast agents, ongoing technical developments of pre-clinical and clinical ultrasound systems, the potential of molecular ultrasound for imaging different diseases at the molecular level, and the translation of molecular ultrasound into the clinic.


Asunto(s)
Medios de Contraste , Imagen Molecular/métodos , Neoplasias/diagnóstico por imagen , Neovascularización Patológica/diagnóstico por imagen , Humanos , Microburbujas , Imagen Molecular/tendencias , Neoplasias/genética , Neoplasias/patología , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Ultrasonografía
20.
Colloids Surf B Biointerfaces ; 75(2): 584-9, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19879738

RESUMEN

In this paper, a single-step room-temperature biosynthetic route for producing gold nanostructures using pear fruit is reported. The alkaline conditions of the pear fruit extract induced gold nanoparticles with plate-like morphologies. Successfully biosynthesized triangular and hexagonal nanoplates were observed, elegantly assembled with hexagonal gold nanoparticles. Nanostructure size, crystal nature, purity and morphologies were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and energy dispersive X-ray analysis (EDAX). The edge lengths of the nanostructures ranged from 200 to 500 nm. Using AFM analysis, the nanohexagons were observed to have a thickness ranging from 12 to 20 nm. The XRD patterns showed a (1 1 1) preferential orientation of the nanostructures. The XPS and EDAX analysis also confirmed the presence of pure-phase Au without any substantial impurities. The preparation of nanostructured gold particles using pear fruit provides an environmentally friendly option, as compared to currently available chemical and/or physical methods.


Asunto(s)
Frutas/química , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Pyrus/química , Temperatura , Álcalis/química , Nanopartículas del Metal/ultraestructura , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Difracción de Rayos X
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