DNA and protein applications of near-infrared dyes

The near-infrared region of the spectrum (650-1100 nm) offers distinct advantages over the traditional UV/vis region for spectroscopic measurements. In the past, the lack of commercially available equipment capable of working in the near infrared limited the utility of near-infrared techniques. However, since the advent of photodiodes and semiconductor lasers, much progress has been made in the development of near-infrared techniques. This paper discusses the use of near-infrared dyes used in DNA and protein applications.     

Safety and efficacy of lenvatinib by starting dose based on body weight in patients with unresectable hepatocellular carcinoma in REFLECT

Journal of Gastroenterology - REFLECT was an open-label, phase 3 study comparing the efficacy and safety of lenvatinib versus sorafenib in patients with unresectable hepatocellular carcinoma...     

Selective and efficient catalytic and photocatalytic oxidation of diphenyl sulphide to sulfoxide and sulfone: the role of hydrogen peroxide and TiO2 polymorph

In this paper, we describe the role of anatase and rutile crystal phases on diphenyl sulphide (Ph₂S) catalytic and photocatalytic oxidation. The highly selective and efficient synthesis of diphenyl sulfoxide (Ph₂SO) and diphenyl sulfone (Ph₂SO₂) at titanium dioxide was demonstrated. Ph₂S oxidation in the presence of hydrogen peroxide at anatase-TiO₂ can take place both as a catalytic and photocatalytic reaction, while at rutile-TiO₂ only photocatalytic oxidation is possible. The reaction at anatase leads mainly to Ph₂SO₂, whereas, in the presence of rutile a complete conversion to Ph₂SO is achieved after only 15 min (nearly 100% selectivity). Studies on the mechanistic details revealed a dual role of H₂O₂. It acts as a substrate in the reaction catalysed only by anatase, but it also plays a key role in alternative photocatalytic oxidation pathways. The presented study shows the applicability of photocatalysis in efficient and selective sulfoxide and sulfone production.

Selective sulfoxide and sulfone production can be precisely controlled by choosing TiO₂ polymorph and the reaction mode (catalysis versus photocatalysis).     

Fe-Doped Barium Lanthanum Titanate as a Competitor to Other Lead-Free Piezoelectric Ceramics

Multiferroic solid solutions of Ba_1−xLa_xTi_1−x/4O₃ and iron (BLFT) were synthesized using the conventional mixed oxide method. The dependence of the piezoelectric coefficients on Fe content in BLFT ceramics was determined by the quasi-static and resonance method. The results indicate that 0.3 mol% addition of Fe³⁺ ions to the ceramic structure increased the value of the piezoelectric parameter d₃₃ to the maximum of 159 pC/N. This puts BLFT ceramics among other good-quality and lead-free piezoelectric ceramics. A major enhancement of dielectric properties related to the manipulation of Fe content in the barium lanthanum titanate (BLT) ceramics system is reported as well.     

Fasting serum sulfate levels before and after development of osteoarthritis in participants of the veterans administration normative aging longitudinal study do not differ from levels in participants in whom osteoarthritis did not develop

OBJECTIVE: To determine whether the development of osteoarthritis (OA) in men over a 33-year period is related to lower sulfate levels in stored serum collected during that time interval. METHODS: Stored serum samples from participants in the Veterans Administration Normative Aging Study were assayed for sulfate by ion-exchange chromatography. Samples had been obtained every 3-5 years during part or all of a 33-year portion of the study. Sulfate levels were determined in serum from all participants who underwent knee replacement surgery and had evidence of radiographic hand OA, from some of the participants who had evidence of radiographic hand OA but had not undergone knee replacement surgery, from all participants who underwent knee replacement surgery but had no evidence of radiographic hand OA, and from age-matched participants who had no evidence of OA by history, physical examination, or hand radiography. RESULTS: Serum sulfate levels in participants, with or without radiographic hand OA and/or knee replacements, who were ages 34-72 years at the first examination, ranged from 0.21 mM to 0.51 mM over the course of a maximum of 33 years. Both the overall mean and median sulfate levels rose from 0.32 mM at age 40-50 years to 0.38 mM at age 70-80 years, and the overall mean and median for all ages was 0.36 mM. There were no significant differences in sulfate levels between subjects in any of the 4 groups. CONCLUSION: There was no evidence of a relationship between these serum sulfate levels and the development of OA. However, all samples were collected after overnight fasting, and no participant was younger than age 34 years at the initiation of the study. It remains to be determined whether differences in the time of ingestion of daily dietary protein providing sulfate are related to the development of OA, or whether sulfate levels measured at an earlier age could be a factor.     

Cases of ineffective anti-hepatitis B vaccination--own observations

Between 1999-2001 there were 6 patients with acute hepatitis B, previously vaccinated according to the recommended schedule of anti-hepatitis B immunization for adults, hospitalized in the Department of Infectious Diseases (Bytom, Silesian University Medical School). The study presents epidemiological and clinical analysis of these cases. Special attention is paid to possibility of immune response failure in spite of anti-hepatitis B vaccination. It is emphasized, that efficiency of active hepatitis B prophylaxis should be verified by estimation of serum anti-HBs antibodies, especially in patients with planned surgery.     

The study of the quercetin action on human erythrocyte membranes

Quercetin is a naturally occurring flavonoid that exerts multiple pharmacological effects. In our previous study, we showed that quercetin greatly affects the lipid membrane. In this report, a study of quercetin on human erythrocyte membrane has been performed to determine the influence of this flavonoid on the fluidity and the conformational changes of membrane proteins. An additional aim of the study was to find how quercetin presence affects the resistance of membrane to haemolytic agents. The results showed that incorporation of quercetin into the erythrocyte membranes caused the changes of the partition coefficient of the Tempo spin label between the water and polar head group phases. In the studies, the W/S ratio has been used as a monitor of changes in protein conformation and in the environment within the membrane. It was observed that quercetin caused an increase in protein-protein interactions in human erythrocyte membranes. Haemolytic action of quercetin in the dark was also investigated. This compound showed protective effect against hypotonic haemolysis. However, in the heat-induced haemolysis quercetin caused acceleration of haemolysis. Dark reaction of erythrocyte with quercetin resulted in a shrinkage of the cells and alteration of their shapes. From the results we have concluded that modification of erythrocyte membrane by quercetin proceeds via reaction with membrane lipids and proteins.     

Transcutaneous and intracutaneous pO2 measurements in the assessment of peripheral arterial occlusive diseases

The purpose of the study was to compare the results of intra- and transcutaneous pO2-measurements of patients suffering from an arterial occlusive disease of the lower extremities (Fontaine I-IV) with that of 20 healthy volunteers. The measurements were performed by one transcutaneous and two intracutaneous pO2-electrodes on the dorsum of the foot. As reference we used the ratio pf/pft of the venous occlusion plethysmography of the calf. Already at rest the transcutaneous pO2 allows a significant separation of healthy persons and patients of Fontaine II. After a 3-minute ischemic period the greatly changed time parameters 'delay-time', 'half-time of the pO2 increase' as well as the 'pO2 recovery time' permit a significant separation of Fontaine III from healthy persons and Fontaine II. The findings show that both methods complete one another. The value of a local pO2 measurement for an individual therapy control is emphasized.     

Estimation of the dietary acrylamide exposure of the Polish population

The objective of our study was to determine acrylamide content in the Polish foods and to assess the average dietary acrylamide exposure of the Polish population. We analysed the acrylamide content in Polish food using GCQ-MS/MS method. The daily dietary acrylamide exposure was computed using a probabilistic approach for the total Polish population (1–96 years) and for the following age groups: 1–6, 7–18 and 19–96, using Monte Carlo simulation technique. To assess the Polish population exposure to acrylamide present in food, food consumption data was taken from the ‘Household Food Consumption and Anthropometric Survey in Poland’. The mean content of acrylamide in tested 225 samples of foodstuffs taken randomly all over Poland, ranged widely from 11 to 3647 μg/kg of product. For the total Polish population (1–96 years) the estimated acrylamide mean exposure is 0.43 μg/kg of body weight per day. The main sources of dietary acrylamide in Polish population were as follow: bread – supplied 45% of total dietary acrylamide intake, French fries and potato crisps – 23%, roasted coffee – 19%.