Imaging of photoacoustic-mediated permeabilization of giant unilamellar vesicles (GUVs).

Target delivery of large foreign materials to cells requires transient permeabilization of the cell membrane without toxicity. Giant unilamellar vesicles (GUVs) mimic the phospholipid bilayer of the cell membrane and are also useful drug delivery vehicles. Controlled increase of the permeability of GUVs is a delicate balance between sufficient perturbation for the delivery of the GUV contents and damage to the vesicles.

Photoacoustic generation of intense and broadband ultrasound pulses with functionalized carbon nanotubes.

Carbon nanotubes (CNT) functionalized with siloxane groups were dissolved in polystyrene/tetrahydrofuran to produce thin films that generate broadband and intense ultrasound pulses when excited by pulsed lasers. These films absorb >99% of light in the visible and near-infrared and show no signs of fatigue after thousands of laser pulses. Picosecond laser pulses with fluences of 50 mJ cm-2 generate photoacoustic waves with exceptionally wide bandwidths (170 MHz at -6 dB) and peak pressures >1 MPa several millimeters away from the source.

Photoacoustic transfection of DNA encoding GFP.

Photoacoustic transfection consists in the use of photoacoustic waves, generated in the thermoelastic expansion of a confined material absorbing a short pulse of a laser, to produce temporary mechanical deformations of the cell membrane and facilitate the delivery of plasmid DNA into cells. We show that high stress gradients, produced when picosecond laser pulses with a fluence of 100 mJ/cm are absorbed by piezophotonic materials, enable transfection of a plasmid DNA encoding Green Fluorescent Protein (gWizGFP, 3.74 MDa) in COS-7 monkey fibroblast cells with an efficiency of 5% at 20 °C, in 10 minutes.

Racial inequities and aging: analysis of the 2010 cohort of the Health, Welfare and Aging Study (SABE).

Introduction: Understanding racial disparities in Brazil has been very complex and poorly investigated in some population segments, such as the elderly individuals.

Objective: This study aimed to present descriptively a comparative analysis in a racial perspective of sociodemographic profile, health conditions, and health service use by older people in the city of São Paulo.

Methods: This is a cross-sectional analysis of the Health, Welfare and Aging Study (SABE).

Multiplex TaqMan qPCR assay for specific identification of encapsulated Trichinella species prevalent in North America.

BACKGROUND Human trichinellosis is a foodborne parasitic zoonotic disease caused by ingestion of raw or undercooked meat infected with nematode larvae of the genus Trichinella. In the USA, sporadic cases and outbreaks caused by the consumption of wild game meat infected with Trichinella have been reported. The current methods for diagnosis such as serology and microscopy are not specific, may result in false negative results, and cannot differentiate encapsulated Trichinella larvae to species level.

Phthalocyanine Labels for Near-Infrared Fluorescence Imaging of Solid Tumors.

Diamagnetic metal complexes of phthalocyanines with n-butoxyl groups in all the α-benzo positions of the macrocycle skeleton, MPc(OBu)8, have strong near-infrared absorptions and intense fluorescences that are Stokes shifted by more than 15 nm. Interestingly, the silicon complex 6 is also remarkably photostable and nontoxic. The use of 6 in the fluorescence imaging of BALB/c mice bearing a 4T1-luc2 tumor in the mammary fat pad unambiguously revealed the presence of the tumor when it was only 1 mm in diameter and was not visible with the naked eye.