Pulsed laser deposition of polytetrafluoroethylene-gold composite layers

PTFE-metal composites are promising candidates for use as sensor materials. In present study PTFE-Au composite layers were deposited by alternated ablation of pressed Teflon pellets and gold plates with focused beam of an ArF excimer laser at 6 J/cm2 fluence, while keeping the substrate at 150 °C temperature. The morphology and chemical composition of the ~3–4 μm average thickness layers was studied by electron microscopy and energy dispersive X-ray spectroscopy. The layers were mainly formed of PTFE gains and clusters which are covered by a conductive Au film. For testing the applicability of such layers as sensing electrodes, composite layers were prepared on one of the two neighbouring electrode of a printed circuit board. Cholesterol and glucose solutions were prepared using 0.1M NaOH solvent containing 10% Triton X-100 surfactant. The electrodes were immersed in the solutions and voltage between the electrodes was measured while a constant current was drawn through the sample. The influence of the analyte concentration on the power spectral density of the voltage fluctuation was studied

Nanoparticle generation from nitinol target using pulsed laser ablation

The influence of experimental conditions (wavelength, liquid environment) on the properties of Ni-Ti nanoparticles generated by nanosecond laser ablation of NiTinol (Shape Memory Alloy) target and the elemental distribution of the irradiated surface were investigated. The studied laser wavelengths were 248 (KrF) and 1064 nm (Q-switched Nd:YAG). Nitinol targets were covered with thin liquid layer of distilled water and ethanol, respectively. The samples were irradiated with various numbers of pulses (500 in case of the investigation of the alloy surface and 20000 for the particle generation) and fluences (2 and 5 J/cm2). The morphology of laser treated NiTi surface and the size of the generated nanoparticles were studied as a function of both the laser fluence and the type of the applied liquids using scanning electron microscopy (SEM). Element mappings were realized by energy-dispersive X-ray spectroscopy (EDX). Our results clearly show that when using ethanol both the laser treated surface and the generated particles had a relatively homogeneous elemental distribution. However, under distilled water the irradiated surface and the generated particles showed a separated presence of Ni and Ti elements. For the higher fluence, formation of core-shell structured particles were observed in water environment

Design, synthesis and biological evaluation of novel estrone phosphonates as high affinity organic anion-transporting polypeptide 2B1 (OATP2B1) inhibitors

Organic anion-transporting polypeptide 2B1 (OATP2B1) is a multispecific membrane transporter mediating the cellular uptake of various exo- and endobiotics, including drugs and steroid hormones. Increased uptake of steroid hormones by OATP2B1 may increase tumor proliferation. Therefore, understanding OATP2B1′ s substrate/inhibitor recognition and inhibition of its function, e.g., in hormone-dependent tumors, would be highly desirable. To identify the crucial structural features that correlate with OATP2B1 inhibition, here we designed modifications at four positions of the estrane skeleton. 13α- or 13β-estrone phosphonates modified at ring A or ring D were synthesized. Hirao and Cu(I)-catalyzed azide–alkyne click reactions served in the syntheses as key steps. 13β-Derivatives displayed outstanding OATP2B1 inhibitory action with IC50 values in the nanomolar range (41–87 nM). A BODIPY-13α-estrone conjugate was additionally synthesized, modified at C-3-O of the steroid, containing a four-carbon linker between the triazole moiety and the BODIPY core. The fluorescent conjugate displayed efficient, submicromolar OATP2B1 inhibitory potency. The newly identified inhibitors and the structure–activity relationships specified here promote our understanding about drug recognition of OATP2B1

Attachment and proliferation of human osteoblast-like cells (MG-63) on laser-ablated titanium implant material.

Demand is increasing for shortening the long (3-6months) osseointegration period to rehabilitate patients' damaged chewing apparatus in as short a time as possible. For dental implants, as for biomaterials in general, the bio- and osseointegration processes can be controlled at molecular and cellular levels by modification of the implant surface. One of the most promising of such surface modifications is laser ablation, as demonstrated by our previous results [46]. Commercially pure (CP4) sand-blasted, acid-etched titanium disks (Denti(R) System Ltd., Hungary) were irradiated with a KrF excimer laser (248nm, fluence 0.4J/cm(2), FWHM 18ns, 2000 pulses), or with a Nd:YAG laser (532nm, 1.3J/cm(2), 10ns, 200 pulses) then examined by SEM, AFM, and XPS. In vitro attachment (24h) and proliferation (72h) of MG-63 osteoblast cells were investigated via dimethylthiazol-diphenyl tetrazolium bromide (MTT), alamarBlue (AB) assays alkaline phosphatase quantification (ALP) and SEM. SEM and AFM revealed significant changes in morphology and roughness. XPS confirmed the presence of TiO2 on each sample; after Nd:YAG treatment a reduced state of Ti (Ti(3+)) was also observed. MTT, AB and ALP measurements detected an increase in the number of cells between the 24- and 72hour observations; however, laser treatment did not affect cell attachment and proliferation significantly

A Koragyermekkori Evés-alvászavar Ambulancia ellátási modelljét kísérô tudományos nyomon követés módszertana = Methodology of scientific monitoring of care in the outpatient clinic of early childhood eating and sleep disorders

Háromrészes cikksorozatunkban a Heim Pál Országos Gyermekgyógyászati Intézet Madarász utcai Koragyermekkori EvésAlvászavar Ambulanciájának klinikai protokollját, az ellátás tudományos nyomonkö vetésének modelljét és kutatásunk elsô statisztikai eredményeit mutatjuk be. Az osztályos háttérrel is rendelkezô ambulancia az egészségügyi szektoron belül – interdiszciplináris ellátási modell keretében – elsôként nyújtott szervezett ellátást hazánkban a kora gyermekkori állapot-, érzelemés viselkedésszabályozási problémákat mutató csecsemôk, kisgyermekek és családjaik számára. = In a three-part article series, we present the clinical protocol used by the Early Childhood Eating and Sleep Disorders Outpatient Clinic at Madarász Street of the Heim Pál National Pediatric Institute; a model of the scientific monitoring of the care; and the first results obtained by this monitoring research. The Clinic that also has a hospital background was the first in the Hungarian health care system to pro - vide organized care for families of infants and young children struggling with early childhood emotional and behavioral regulation problems within a framework of interdisciplinary care model