Development of a biosensor for human blood: new routes to body fluid identification

The identification of human blood at a crime scene can provide crucial information to an investigation whilst also providing a source of nuclear material which can be targeted for DNA profiling. Here, we report on the development of an immunofluorescent biosensor for the identification of human blood which has the potential to overcome the drawbacks of the current body fluid identification techniques. An antibody (Ab) raised against human erythrocytes was conjugated to fluorescent semiconductor quantum dots (QDs) by sulfhydryl chemistry. The conjugation was verified by agarose gel electrophoresis and immunohistochemistry. Incubation of liquid blood samples with the conjugated nanocrystals was shown to quench the fluorescence emission spectra in a concentration-dependent manner. A different effect was observed with unconjugated QDs incubated in blood. Full profiles were obtained from blood samples previously treated with the Ab-QDs, demonstrating that the method does not interfere with DNA profiling. To our knowledge, this is the first example of a hybrid Ab-QD sensor that has the potential to be employed for the identification of human blood. The results of this study are expected to open up a new research direction in the field of body fluid detection.     

Roots and polynomials as Homeomorphic spaces

We provide a unified, elementary, topological approach to the classical results stating the continuity of the complex roots of a polynomial with respect to its coefficients, and the continuity of the coefficients with respect to the roots. In fact, endowing the space of monic polynomials of a fixed degree n and the space of n roots with suitable topologies, we are able to formulate the classical theorems in the form of a homeomorphism. Related topological facts are also considered.     

Vocal aging and the impact on daily life: a longitudinal study

Longitudinal studies on vocal aging are scarce, and information on the impact of age-related voice changes on daily life is lacking. This longitudinal study reports on age-related voice changes and the impact on daily life over a time period of 5 years on 11 healthy male speakers, age ranging from 50 to 81 years. All males completed a questionnaire on vocal performance in daily life, and perceptual and acoustical analyses of vocal quality and analyses of maximum performance tasks of vocal function (voice range profile) were performed. Results showed a significant deterioration of the acoustic voice signal as well as increased ratings on vocal roughness judged by experts after the time period of 5 years. An increase of self-reported voice instability and the tendency to avoid social parties supported these findings. Smoking males had a lower speaking fundamental frequency compared with nonsmoking males, and this seemed reversible for males who stop smoking. This study suggests a normal gradual vocal aging process with clear consequences in daily life, which should be taken into consideration in clinical practice as well as in studies concerning communication in social life.     

Novel Copolymers of Styrene. 3. Oxy Ring-disubstituted 2-cyano-3-phenyl-2-propenamides

Novel electrophilic trisubstituted ethylene monomers, oxy ring-disubstituted 2-cyano-3-phenyl-2-propenamides, RC₆H₃CH? C(CN)CONH₂ (where R is 2,3-(CH₃O)₂, 2,4-(CH₃O)₂, 2,5-(CH₃O)₂, 2,6-(CH₃O)₂, 3,4-(CH₃O)₂, 3,5-(CH₃O)₂, 3-CH_3?4-CH₃O, 3-C₂H₅O-4-CH₃O, 3,4-(C₆H₅CH₂O)₂, 2-C₆H₅CH₂O-3-CH₃O, 3-C₆H₅CH₂O-4-CH₃O, 4-C₆H₅CH₂O-3-CH₃O) were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and cyanoacetamide, and characterized by CHN analysis, IR, ¹H- and ¹³C-NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, AIBN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, ¹H- and ¹³C-NMR. High T_g of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 300–500°C range with residue (2–9% wt), which then decomposed in the 500–800°C range.     

Development and Characterization of an Orodispersible Film for Vitamin D3 Supplementation

Vitamin D plays a crucial and very well-known role in regulation of calcium homeostasis and bone metabolism and mineralization. However, a huge and more recent body of evidence supports the positive influence of vitamin D on the regulation of immune response, ranging from protection against respiratory tract infections to prevention and management of asthma. Nevertheless, vitamin D deficiency is a very common condition and there is an increasing need for suitable products for proper supplementation, allowing good compliance also in specific populations. Orally disintegrating tablets (ODT) were first developed to overcome the difficulty experienced by pediatric and geriatric patients of swallowing traditional oral dosage forms and, recently, orodispersible films (ODF) are gaining popularity as novel dosage form for assuming active pharmaceutical ingredients, vitamins, and ingredients for food supplements. This study describes a 2000 IU Vitamin D3 ODF for daily intake, consisting of hydrophilic polymers and suitable excipients, manufactured by film-casting process. Elongation-at-break (E%), Young’s modulus (Y), and tensile strength (TS) were investigated using a dynamometer. Chemical stability was evaluated assaying the vitamin D3 in the films stored at different environmental conditions. In addition, in vitro disintegration and dissolution studies were performed. Correlation existed between the mechanical properties of the film and the residual water, acting as plasticizer. The stability study showed that vitamin D3 assay was ≥90% also after 3 months at 40 °C. The film disintegrated in less than 1 min and the vitamin D3 released was ≥75% after 15 min. An ODF with suitable properties can be manufactured and used as innovative dosage form for vitamin D3 food supplements.     

Versatile Bispidine-Based Bifunctional Chelators for 64CuII-Labelling of Biomolecules

Bifunctional chelators as parts of modular metal-based radiopharmaceuticals are responsible for stable complexation of the radiometal ion and for covalent linkage between the complex and the targeting vector. To avoid loss of complex stability, the bioconjugation strategy should not interfere with the radiometal chelation by occupying coordinating groups. The C9 position of the very stable Cu^II chelator 3,7-diazabicyclo[3.3.1]nonane (bispidine) is virtually predestined to introduce functional groups for facile bioconjugation as this functionalisation does not disturb the metal binding centre. We describe the preparation and characterisation of a set of novel bispidine derivatives equipped with suitable functional groups for diverse bioconjugation reactions, including common amine coupling strategies (bispidine-isothiocyanate) and the Cu-free strain-promoted alkyne–azide cycloaddition. We demonstrate their functionality and versatility in an exemplary way by conjugation to an antibody-based biomolecule and validate the obtained conjugate in vitro and in vivo.     

Densitometric Analysis of Diosgenin in Methanolic Extracts of Allium ursinum Collected at Different Times During Plant Development

JPC – Journal of Planar Chromatography – Modern TLC - Diosgenin in methanolic extracts of fresh leaves and bulbs of Allium ursinum collected at different times during plant development...     

Acoustical analysis and perceptual evaluation of tracheoesophageal prosthetic voice

Voice analysis was performed on 21 “standard” laryngectomized, male patients with a Provox® voice prosthesis, along with an age- and sex-matched control group of 20 normal speakers, using acoustical analyses (MDVP and CSL, Kay Elemetrics Corp.), maximum phonation time measurements, and perceptual evaluations. Comparison between MDVP and CSL revealed that the latter was not useful for the analysis of laryngectomized prosthetic voices. In contrast, MDVP seems suitable for this purpose, and contains a large number of parameters that significantly differentiate between patient and control speakers, as did the perceptual ratings and the maximum phonation time. Fundamental frequency appeared to be comparable for patients and control speakers. A significant influence of stoma occlusion and age was found for some voice parameters. Factor analyses showed correlations between the different MDVP parameters and correlations between the MDVP parameters and the perceptual ratings.