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1.
Hosp Pediatr ; 13(12): 1039-1047, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37927058

RESUMO

BACKGROUND AND OBJECTIVES: Performance of minor procedures is highly variable among pediatric hospitalists. Our objective was to describe procedural frequency and measure self-assessed competence in recommended minor procedures among practicing hospitalists. METHODS: An electronic survey was administered across 20 US institutions. An individual survey assessed training, frequency, independence, and success in performing 11 minor procedures. The site survey described practice settings at participating study sites. The primary outcome was respondents' self-assessed competence (SAC), derived by averaging self-assessed independence and success scores (each on a 5-point Likert scale) across all 11 minor procedures. Associations between predictor variables and SAC were determined through analysis of variance for categorical variables and fitted regression models for continuous variables. RESULTS: Of the 360 survey respondents, the majority were female (70%), not fellowship trained (78%), and had 10 years or fewer experience as a hospitalist (72%). Lumbar puncture and bag mask ventilation were most frequently performed. Greater procedural frequency and time since graduation from training were associated with higher SAC scores among respondents. Practice characteristics, including comanagement of patients and reserved time for practicing procedures, were associated with higher SAC scores. The presence of a simulation center and fellowship program was not associated with higher SAC scores. CONCLUSIONS: Pediatric hospitalists that performed procedures more frequently had higher self-assessed procedural competence. Tailored opportunities with increased hands-on experience in performing minor procedures may be important to develop and maintain procedural skills.


Assuntos
Médicos Hospitalares , Humanos , Masculino , Feminino , Criança , Inquéritos e Questionários , Punção Espinal , Bolsas de Estudo
2.
Artigo em Inglês | MEDLINE | ID: mdl-36438886

RESUMO

South Asians represent a growing percentage of the diverse population in the U.S. and are disproportionately impacted by a greater burden of aggressive and premature cardiovascular disease. There are multiple potential explanations for these findings including a high prevalence of traditional risk factors (particularly diabetes, dyslipidemia, and obesity), a genetic predisposition, and unique lifestyle factors. In this review, we discuss the cardiovascular risk stratification and disease management goals for South Asian adults. We review the pharmacologic and non-pharmacologic interventions studied in this population and discuss the role of specialized clinics and digital outreach to improve care for this vulnerable group of patients.

3.
Aliment Pharmacol Ther ; 54 Suppl 1: S24-S32, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34927758

RESUMO

Symptoms of irritable bowel syndrome (IBS) characteristically fluctuate over time. We aimed to review the natural history of IBS and IBS subgroups including bowel habit disturbances, and the overlap of IBS with other gastrointestinal disorders. The community incidence of IBS is approximately 67 per 1000 person years. The prevalence of IBS is stable over time because symptoms fluctuate and there is a portion who experience resolution of their GI symptoms similar in number to those developing new-onset IBS. The proportion who report resolution of symptoms varies amongst population-based studies from 17% to 55%. There is evidence of substantial movement between subtypes of IBS. For example in a clinical trial cohort, only one in four patients retained their baseline classification throughout the study periods, two in three moved between IBS-C (constipation) and IBS-M (mixed), while over half switched between IBS-D (diarrhoea) and IBS-M. The least stable group was IBS-M. There are very limited data on drivers of bowel habit change in IBS. There are emerging evidence fluctuations in intestinal immune activity might account for symptom variability over time. It is of clinical importance to recognise the substantial overlap of IBS symptoms with other gastrointestinal syndromes including gastro-oesophageal reflux disease. This is important to ensure the correct clinical diagnosis of IBS is made and patients are not over investigated. Knowledge of the natural history, stability of subgroups and overlap of IBS with other gastrointestinal conditions should be considered in therapeutic decision making.


Assuntos
Síndrome do Intestino Irritável , Constipação Intestinal/epidemiologia , Constipação Intestinal/etiologia , Defecação , Diarreia/epidemiologia , Hábitos , Humanos , Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/epidemiologia
4.
Nanotechnology ; 33(8)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34753112

RESUMO

The multifunctional upconversion nanoparticles (UCNPs) are fascinating tool for biological applications. In the present work, photon upconverting NaGdF4:Yb,Er and Ag nanoparticles decorated NaGdF4:Yb,Er (NaGdF4:Yb,Er@Ag) nanoparticles were prepared using a simple polyol process. Rietveld refinement was performed for detailed crystal structural and phase fraction analysis. The morphology of the NaGdF4:Yb,Er@Ag was examined using high-resolution transmission electron microscope, which reveals silver nanoparticles of 8 nm in size were decorated over spherical shaped NaGdF4:Yb,Er nanoparticles with a mean particle size of 90 nm. The chemical compositions were confirmed by EDAX and inductively coupled plasma-optical emission spectrometry analyses. The upconversion luminescence (UCL) of NaGdF4:Yb,Er at 980 nm excitation showed an intense red emission. After incorporating the silver nanoparticles, the UCL intensity decreased due to weak scattering and surface plasmon resonance effect. The VSM magnetic measurement indicates both the UCNPs possess paramagnetic behaviour. The NaGdF4:Yb,Er@Ag showed computed tomography imaging. Magnetic resonance imaging study exhibited better T1 weighted relaxivity in the NaGdF4:Yb,Er than the commercial Gd-DOTA. For the first time, the optical trapping was successfully demonstrated for the upconversion NaGdF4:Yb,Er nanoparticle at near-infrared 980 nm light using an optical tweezer setup. The optically trapped UCNP possessing paramagnetic property exhibited a good optical trapping stiffness. The UCL of trapped single UCNP is recorded to explore the effect of the silver nanoparticles. The multifunctional properties for the NaGdF4:Yb,Er@Ag nanoparticle are demonstrated.

5.
Mikrochim Acta ; 187(6): 317, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385722

RESUMO

The effect of novel silver nanowire encapsulated NaGdF4:Yb,Er hybrid nanocomposite on the upconversion emission and bioimaging properties has been investigated. The upconvension nanomaterials were synthesised by polyol method in the presence of ethylene glycol, PVP and ethylenediamine. The NaGdF4:Yb,Er-Ag hybrid was formed with upconverting NaGdF4:Yb,Er nanoparticles of size ~ 80 nm and silver nanowires of thickness ~ 30 nm. The surface plasmon induced by the silver ion in the NaGdF4:Yb,Er-Ag nanocomposite resulted an intense upconversion green emission at 520 nm and red emission at 660 nm by NIR diode laser excitation at 980 nm wavelength. The UV-Vis-NIR spectral absorption at 440 nm and 980 nm, the intense Raman vibrational modes and the strong upconversion emission results altogether confirm the localised surface plasmon resonance effect of silver ion in the hybrid nanocomposite. MRI study of both NaGdF4:Yb,Er nanoparticle and NaGdF4:Yb,Er-Ag nanocomposite revealed the T1 relaxivities of 22.13 and 10.39 mM-1 s-1, which are larger than the commercial Gd-DOTA contrast agent of 3.08 mM-1 s-1. CT imaging NaGdF4:Yb,Er-Ag and NaGdF4:Yb,Er respectively showed the values of 53.29 HU L/g and 39.51 HU L/g, which are higher than 25.78 HU L/g of the CT contrast agent Iobitridol. The NaGdF4:Yb,Er and NaGdF4:Yb,Er-Ag respectively demonstrated a negative zeta potential of 54 mV and 55 mV, that could be useful for biological application. The in vitro cytotoxicity of the NaGdF4:Yb,Er tested in HeLa and MCF-7 cancer cell line by MTT assay demonstrated a cell viability of 90 and 80 %, respectively. But, the cell viability of NaGdF4:Yb,Er-Ag slightly decreased to 80 and 78%. The confocal microscopy imaging showed that the UCNPs are effectively up-taken inside the nucleolus of the cancer cells, and it might be useful for NIR laser-assisted phototherapy for cancer treatment. Graphical abstract.


Assuntos
Meios de Contraste/química , Corantes Fluorescentes/química , Fluoretos/química , Gadolínio/química , Nanocompostos/química , Nanofios/química , Linhagem Celular Tumoral , Meios de Contraste/efeitos da radiação , Érbio/química , Érbio/efeitos da radiação , Corantes Fluorescentes/efeitos da radiação , Fluoretos/efeitos da radiação , Gadolínio/efeitos da radiação , Humanos , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/química , Nanopartículas Metálicas/efeitos da radiação , Microscopia Confocal , Microscopia de Fluorescência , Nanocompostos/efeitos da radiação , Nanofios/efeitos da radiação , Prata/química , Prata/efeitos da radiação , Tomografia Computadorizada por Raios X , Itérbio/química , Itérbio/efeitos da radiação
6.
Dalton Trans ; 47(41): 14426-14430, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30272068

RESUMO

By using a terephthalate containing ionic liquid, a new metal-organic framework, hcp UiO-66, comprising (Zr12O8(OH)14) double clusters and terephthalate ligands has been synthesized. The hydrothermal synthesis of hcp UiO-66 might help to establish metal-organic frameworks for industrial scale applications.

7.
Clin Pediatr (Phila) ; 57(12): 1391-1397, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29992835

RESUMO

We aimed to determine median cumulative radiation exposure in pediatric intensive care unit (PICU) patients, proportion of patients with high radiation exposure (above annual average radiation per person of 6.2 mSv), and determine risk factors for high exposure. This was a retrospective chart review of PICU patients up to 18 years of age admitted to a large community hospital over 2 years. Radiologic studies and radiation exposure were determined for each patient, and total hospital radiation exposure was classified as high (>6.2 mSv) or not (≤6.2 mSv). Median radiation exposure per patient was 0.2 mSv (interquartile range = 2.1) and 11.7% of patients received >6.2 mSv radiation during their hospitalization. Factors associated with high radiation exposure included admission for trauma or surgery, number of computed tomography scans, age, and PICU length of stay (all P < .0001). We concluded that subsets of PICU patients are at risk of high radiation exposure. Policies and protocols may help minimize radiation exposure among PICU patients.


Assuntos
Pacientes Internados/estatística & dados numéricos , Unidades de Terapia Intensiva Pediátrica , Exposição à Radiação/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Hospitais Comunitários , Humanos , Lactente , Recém-Nascido , Tempo de Internação/estatística & dados numéricos , Masculino , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X/estatística & dados numéricos
8.
RSC Adv ; 8(14): 7457-7464, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35539119

RESUMO

The present case study critically assesses the efficacy of a previously proposed segmentation methodology as a means to discriminate phases via post-processing the image of an elemental map. In the Bi2Te2.5S0.5 multiphase compound, the reference spectra of the Bi2Te3 and Bi2Te2S phases are distinct enough to effectively distinguish two phases during map acquisition. Since the counts of the sulphur-K peak in the X-ray emission data are significantly higher for Bi2Te2S compared to Bi2Te3, the segmentation methodology exploits this variation and enables successful phase discrimination via post-processing the image of the elemental map.

9.
J Magn Reson ; 282: 89-103, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28797926

RESUMO

An improved implementation of single-crystal magic-angle-spinning (MAS) NMR is presented which gives access to chemical shift tensors both in orientation (relative to the crystal axis system) and principal axis values. For mounting arbitrary crystals inside ordinary MAS rotors, a mounting tool is described which allows to relate the crystal orientation determined by diffraction techniques to the rotor coordinate system. The crystal is finally mounted into a MAS rotor equipped with a special insert which allows a defined reorientation of the single-crystal by 90°. The approach is based on the idea that the dispersive spectra, which are obtained when applying read-pulses at specific rotor-phases, not only yield the size of the eigenvalues but also encode the orientation of the different chemical shift (rank-2) tensors. For this purpose two 2D-data sets with orthogonal crystal orientation are fitted simultaneously. The presented analysis for chemical shift tensors is supported by an analytical formula which allows fast calculation of phase and amplitude of individual spinning side-bands and by a protocol which solves the problem of finding the correct reference phase of the spectrum. Different rotor-synchronized pulse-sequences are introduced for the same reason. Experiments are performed on L-alanine and O-phosphorylethanolamine and the observed errors are analyzed in detail. The experimental data are opposed to DFT-computed chemical shift tensors which have been obtained by the extended embedded ion method.

10.
J Am Heart Assoc ; 6(7)2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28668820

RESUMO

BACKGROUND: Previous studies have documented a high prevalence of atrial fibrillation (AF) in individuals with obstructive sleep apnea (OSA). Central sleep apnea (CSA) has been associated with AF in patients with heart failure. However, data from prospective cohorts are sparse and few studies have distinguished the associations of obstructive sleep apnea from CSA with AF in population studies. METHODS AND RESULTS: We assessed the association of obstructive sleep apnea and CSA with incident AF among 2912 individuals without a history of AF in the SHHS (Sleep Heart Health Study), a prospective, community-based study of existing ("parent") cohort studies designed to evaluate the cardiovascular consequences of sleep disordered breathing. Incident AF was documented by 12-lead ECG or assessed by the parent cohort. obstructive sleep apnea was defined by the obstructive apnea-hypopnea index (OAHI). CSA was defined by a central apnea index ≥5 or the presence of Cheyne Stokes Respiration. Logistic regression was used to assess the association between sleep disordered breathing and incident AF. Over a mean of 5.3 years of follow-up, 338 cases of incident AF were observed. CSA was a predictor of incident AF in all adjusted models and was associated with 2- to 3-fold increased odds of developing AF (central apnea index ≥5 odds ratio [OR], 3.00, 1.40-6.44; Cheyne-Stokes respiration OR, 1.83, 0.95-3.54; CSA or Cheyne-Stokes respiration OR, 2.00, 1.16-3.44). In contrast, OAHI was not associated with incident AF (OAHI per 5 unit increase OR, 0.97, 0.91-1.03; OAHI 5 to <15 OR, 0.84, 0.59-1.17; OAHI 15 to <30 OR, 0.93, 0.60-1.45; OAHI ≥30 OR, 0.76, 0.42-1.36). CONCLUSIONS: In a prospective, community-based cohort, CSA was associated with incident AF, even after adjustment for cardiovascular risk factors.


Assuntos
Fibrilação Atrial/etiologia , Apneia do Sono Tipo Central/complicações , Apneia Obstrutiva do Sono/complicações , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco
11.
Pharm Dev Technol ; 22(1): 90-102, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27291246

RESUMO

In the present study, a lyophilized milk-based solid dispersion (SD) of ritonavir (RTV) was developed with the goal of improving its aqueous solubility. The SD was prepared by lyophilization, and characterized for its physicochemical and functional properties. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), photomicroscopy and powder X-ray diffraction (PXRD) were used to confirm the formation and robustness of the SD formulation. The prepared SD formulations were functionally evaluated by saturation solubility, in vitro drug release and ex vivo permeation studies. The optimized SD formulation exhibited a significantly higher (30-fold) aqueous solubility (11.36 ± 0.06 µg/mL), compared to the pure RTV (0.37 ± 0.03 µg/mL). The in vitro dissolution studies revealed a significantly higher (∼10-fold) efficiency of the optimized SD formulation in releasing the RTV, compared to the pure RTV. The ex vivo permeation studies with the everted intestine method showed that prepared SD formulation significantly improved the permeation of RTV (75.6 ± 3.09, % w/w), compared to pure RTV (20.45 ± 1.68, % w/w). Thus, SD formulation utilizing lyophilized milk as a carrier appears to be a promising alternative strategy to improve the aqueous solubility of poorly water soluble drugs.


Assuntos
Liofilização , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/farmacocinética , Absorção Intestinal , Ritonavir/química , Ritonavir/farmacocinética , Animais , Varredura Diferencial de Calorimetria , Inibidores do Citocromo P-450 CYP3A/química , Inibidores do Citocromo P-450 CYP3A/farmacocinética , Feminino , Liofilização/métodos , Mucosa Intestinal/metabolismo , Masculino , Micelas , Leite/química , Permeabilidade , Difração de Pó , Ratos Sprague-Dawley , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X
12.
Eur J Pharm Sci ; 108: 23-35, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590125

RESUMO

In an attempt to improve the solubility and permeability of Standardized Bacopa Extract (SBE), a complexation approach based on phospholipid was employed. A solvent evaporation method was used to prepare the SBE-phospholipid complex (Bacopa Naturosome, BN). The formulation and process variables were optimized using a central-composite design. The formation of BN was confirmed by photomicroscopy, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Powder X-ray Diffraction (PXRD). The saturation solubility, the in-vitro dissolution, and the ex-vivo permeability studies were used for the functional evaluation of the prepared complex. BN exhibited a significantly higher aqueous solubility compared to the pure SBE (20-fold), or the physical mixture of SBE and the phospholipid (13-fold). Similarly, the in-vitro dissolution revealed a significantly higher efficiency of the prepared complex (BN) in releasing the SBE (>97%) in comparison to the pure SCE (~42%), or the physical mixture (~47%). The ex-vivo permeation studies showed that the prepared BN significantly improved the permeation of SBE (>90%), compared to the pure SBE (~21%), or the physical mixture (~24%). Drug-phospholipid complexation may thus be a promising strategy for solubility enhancement of bioactive phytoconstituents.


Assuntos
Bacopa/química , Excipientes/química , Fosfolipídeos/química , Compostos Fitoquímicos/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Antidepressivos/administração & dosagem , Disponibilidade Biológica , Química Farmacêutica , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Masculino , Camundongos , Tamanho da Partícula , Permeabilidade , Difração de Pó , Solubilidade
13.
J Am Chem Soc ; 139(2): 904-909, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-27992224

RESUMO

Microporous organically pillared layered silicates (MOPS) are a class of microporous hybrid materials that, by varying pillar density, allows for optimization of guest recognition without the need to explore different framework topologies. MOPS are found to be capable of discriminating two very similar gases, carbon dioxide and acetylene, by selective gate-opening solely through quenching pillar dynamics. Contrary to conventional gate-opening in metal organic frameworks, the additional adsorption capacity is realized without macroscopic volume changes, thus avoiding mechanical stress on the framework. Of the two gases studied, only CO2 can accomplish freezing of pillar dynamics. Moreover, the shape of the slit-type micropores in MOPS can easily be fine-tuned by reducing the charge density of the silicate layers. This concomitantly reduces the Coulomb attraction of cationic interlayer space and anionic host layers. Surprisingly, we found that reducing the charge density then alters the gate-opening mechanism to a conventional structural gate-opening involving an increase in volume.

14.
Phys Chem Chem Phys ; 18(48): 32814-32819, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27878169

RESUMO

Multiphase thermoelectric materials have recently attracted considerable attention due to the high thermoelectric efficiencies which can be achieved in these compounds compared to their single-phase counterparts. However, there is very little known on the structural evolution of these phases as a function of temperature. In this work we performed an in situ high temperature structural characterisation of recently reported high efficiency p-type multiphase (PbTe)0.65(PbS)0.25(PbSe)0.1 compounds by hot stage transmission electron microscopy and high-resolution neutron powder diffraction. We observed the microstructural evolution of precipitates and determined the lattice parameters of phases as a function of temperature for materials, which have been heavily and lightly doped with sodium. The role of the sodium is to optimize the concentration of charge carriers. It has been shown to distribute heterogeneously between the phases in multiphase compounds. The dissolution of secondary phases is found to occur at elevated temperatures. Although sodium concentration produces no significant differences between the lattice constants of the phases and the dissolution sequence of precipitates, it affects quite significantly the kinetics of precipitation. The heavily doped samples reach structural thermodynamic equilibrium more quickly than the lightly doped compound. These results are a step forward in designing high performance multiphase thermoelectric materials.

15.
Insights Imaging ; 6(5): 559-72, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26337049

RESUMO

The purpose of this article is to describe the various portosystemic collateral pathways pertinent to portal hypertension on multi-detector row computed tomography (MDCT) and their clinical relevance, with special emphasis on the uncommon ones. The knowledge and understanding of the various patterns of portosystemic collateral channels has important implications both for the clinician and the interventionist. MDCT with its advanced post processing capabilities can exquisitely demonstrate these vascular pathways to help in therapeutic decision making. Teaching points • Portosystemic collaterals are an important cause of bleeding and hepatic encephalopathy. • Radiologists should be familiar with the imaging findings to effectively identify them. • Pre-operative knowledge of portosystemic collaterals is essential to avoid inadvertent vascular injury.

16.
J Clin Diagn Res ; 8(10): SC01-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25478430

RESUMO

BACKGROUND AND OBJECTIVES: The chromosomal abnormalities are one of the important causes of male infertility. In view of the genetic risks for the next generation, the importance of careful evaluation of karyotype is essential. The objective of this study was to determine the frequency of chromosomal abnormalities in infertile men with primary infertility from Indian population. MATERIALS AND METHODS: The 78 infertile men with primary infertility, out of which 26 men were azoospermic, 19 men were oligospermic, 4 men were asthenospermic and 29 men were oligoasthenospermic were studied. Karyoptying was performed on peripheral blood lymphocytes by using the Giemsa trypsin banding (GTG) banding technique. Additional data was collected from published studies in Indian population leading to a total of 1814 cases. RESULTS: Chromosome analysis of 78 infertile males showed major chromosome abnormalities in 10.2%, with 6.4% in autosomal chromosome abnormalities and 3.8% in sex chromosome abnormalities. The incidence of major chromosome abnormalities in oligospermic males were 21% and azoospermic males were 15.4 %. Chromosomal polymorphic variants were identified to be 16.7%. Combining the data from other published studies identified 153/ 1814 (8.4%) infertile men of chromosomal abnormalities; with 10.8% in azoospermia, 7.3% in oligospermia and 7.3% in oligoasthenoteratospermic from India. INTERPRETATION AND CONCLUSION: The overall high prevalence of chromosomal abnormalities in infertile males suggests that the conventional chromosomal analysis is an important investigative tool for male infertility, especially prior to use of any assisted reproductive techniques.

17.
Arterioscler Thromb Vasc Biol ; 34(12): 2563-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25278288

RESUMO

OBJECTIVE: Current antiplatelet strategies to prevent myocardial infarction and stroke are limited by bleeding risk. A better understanding of the roles of distinct platelet-activating pathways is needed. We determined whether platelet activation by 2 key primary activators, thrombin and collagen, plays distinct, redundant, or interacting roles in tail bleeding and carotid thrombosis in mice. APPROACH AND RESULTS: Platelets from mice deficient for the thrombin receptor protease-activated receptor-4 (Par4) and the collagen receptor glycoprotein VI protein (GPVI) lack responses to thrombin and collagen, respectively. We examined tail bleeding and FeCl3-induced carotid artery occlusion in mice lacking Par4, GPVI, or both. We also examined a series of Par mutants with increasing impairment of thrombin signaling in platelets. Ablation of thrombin signaling alone by Par4 deficiency increased blood loss in the tail bleeding assay and impaired occlusive thrombus formation in the carotid occlusion assay. GPVI deficiency alone had no effect. Superimposing GPVI deficiency on Par4 deficiency markedly increased effect size in both assays. In contrast to complete ablation of thrombin signaling, 9- and 19-fold increases in EC50 for thrombin-induced platelet activation had only modest effects. CONCLUSIONS: The observation that loss of Par4 uncovered large effects of GPVI deficiency implies that Par4 and GPVI made independent, partially redundant contributions to occlusive thrombus formation in the carotid and to hemostatic clot formation in the tail under the experimental conditions examined. At face value, these results suggest that thrombin- and collagen-induced platelet activation can play partially redundant roles, despite important differences in how these agonists are made available to platelets.


Assuntos
Trombose das Artérias Carótidas/sangue , Colágeno/sangue , Hemorragia/sangue , Ativação Plaquetária/fisiologia , Trombina/metabolismo , Animais , Plaquetas/metabolismo , Trombose das Artérias Carótidas/etiologia , Hemorragia/etiologia , Hemostasia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Glicoproteínas da Membrana de Plaquetas/deficiência , Glicoproteínas da Membrana de Plaquetas/genética , Receptores Ativados por Proteinase/sangue , Receptores Ativados por Proteinase/deficiência , Receptores Ativados por Proteinase/genética , Receptores de Trombina/sangue , Receptores de Trombina/deficiência , Receptores de Trombina/genética , Cauda
18.
Indian J Hum Genet ; 18(1): 117-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22754235

RESUMO

We present a case with a 4p terminal deletion, evidenced in GTG-banded chromosome study. Phenotypic signs described in the classical Wolf-Hirschhorn syndrome were found on clinical examination of our patient.

19.
Phys Chem Chem Phys ; 14(33): 11610-25, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22801707

RESUMO

The electrical conductivity of aluminium doped zinc oxide (AZO, ZnO:Al) materials depends on doping induced defects and grain structure. This study aims at relating macroscopic electrical conductivity of AZO nanoparticles with their atomic structure, which is non-trivial because the derived materials are heavily disordered and heterogeneous in nature. For this purpose we synthesized AZO nanoparticles with different doping levels and narrow size distribution by a microwave assisted polyol method followed by drying and a reductive treatment with forming gas. From these particles electrically conductive, optically transparent films were obtained by spin-coating. Characterization involved energy-dispersive X-ray analysis, wet chemical analysis, X-ray diffraction, electron microscopy and dynamic light scattering, which provided a basis for a detailed structural solid-state NMR study. A multinuclear ((27)Al, (13)C, (1)H) spectroscopic investigation required a number of 1D MAS NMR and 2D MAS NMR techniques (T(1)-measurements, (27)Al-MQMAS, (27)Al-(1)H 2D-PRESTO-III heteronuclear correlation spectroscopy), which were corroborated by quantum chemical calculations with an embedded cluster method (EEIM) at the DFT level. From the combined data we conclude that only a small part of the provided Al is incorporated into the ZnO structure by substitution of Zn. The related (27)Al NMR signal undergoes a Knight shift when the material is subjected to a reductive treatment with forming gas. At higher (formal) doping levels Al forms insulating (Al, H and C containing) side-phases, which cover the surface of the ZnO:Al particles and increase the sheet resistivity of spin-coated material. Moreover, calculated (27)Al quadrupole coupling constants serve as a spectroscopic fingerprint by which previously suggested point-defects can be identified and in their great majority be ruled out.

20.
Am J Cardiol ; 110(6): 891-6, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22727181

RESUMO

Abdominal aortic calcium (AAC) is associated with incident cardiovascular disease. However, the age- and gender-related distribution of AAC in a community-dwelling population free of standard cardiovascular disease risk factors has not been described. A total of 3,285 participants (aged 50.2 ± 9.9 years) in the Framingham Heart Study Offspring and Third Generation cohorts underwent abdominal multidetector computed tomography from 1998 to 2005. The presence and amount of AAC was quantified (Agatston score) by an experienced reader using standardized criteria. A healthy referent subsample (n = 1,656, 803 men) free of hypertension, hyperlipidemia, diabetes, obesity, and smoking was identified, and participants were stratified by gender and age (<45, 45 to 54, 55 to 64, 65 to 74, and ≥75 years). The prevalence and burden of AAC increased monotonically and supra-linearly with age in both genders but was greater in men than in women in each age group. For those <45 years old, <16% of the referent subsample participants had any quantifiable AAC. However, for those >65 years old, nearly 90% of the referent participants had >0 AAC. Across the entire study sample, AAC prevalence and burden similarly increased with greater age. Defining the 90th percentile of the referent group AAC as "high," the prevalence of high AAC was 19% for each gender in the overall study sample. The AAC also increased across categories of 10-year coronary heart disease risk, as calculated using the Framingham Risk Score, in the entire study sample. We found AAC to be widely prevalent, with the burden of AAC associated with 10-year coronary risk, in a white, free-living adult cohort.


Assuntos
Aorta Abdominal/patologia , Doenças da Aorta/epidemiologia , Calcinose/epidemiologia , Adulto , Fatores Etários , Aorta Abdominal/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Prevalência , Fatores de Risco
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