COPPER BENZOCHLORIN, A NOVEL PHOTOSENSITIZER FOR PHOTODYNAMIC THERAPY: EFFECTS ON A TRANSPLANTABLE UROTHELIAL TUMOR

Abstract— An iminum salt of octaethylbenzochlorin with copper in the aromatic ring, CDSI, was tested for its tumoricidal effects on theA–27 N-[4-(5-notro-2-furyl)-2-thiazoly] formamide tumor line. CDSI was found to be an effective photosensitiz4r in vivo when used in combination with either a xenon arc lamp or a pulsed alexandrite laser. Hemodynamically, CDSI and light caused a rapid decrease in tumor blood flow. skin photosensitization was found to be minimal when drug-injected mice werwe illuminated in a solar simulator.     

Einfluß von Form und Polarität der Moleküle auf das Röntgenspektrum von Flüssigkeiten

Zeitschrift für Physik A Hadrons and nuclei - Im Röntgenspektrogramm der meisten Flüssigkeiten tritt nur ein einziger intensiver „amorpher Ring“ auf. Dessen Zusammenhang...     

In situ electrochemical solid-phase extraction of anions and cations using polypyrrole and overoxidized sulfonated polypyrrole

A new method for the extraction of both anions and cations is proposed using electro-synthesized polypyrrole (PPy) and overoxidized sulfonated polypyrrole film (OSPPy). In situ anion (chloride, nitrate, sulfate) and cation (calcium, magnesium) uptake and release were examined under controlled potential conditions for prospective applications in electrochemically controlled solid-phase extraction (EC-SPE). The PPy film was used as an anode (anion-exchanger) and OSPPy film was used as a cathode (cation-exchanger) material and reverse order of the electrodes were investigated in EC-SPE. This new cell arrangement containing two ion exchanger polymer electrodes was developed to provide in situ removal of both anions and cations from aqueous solution. Simple preparation of the film coatings on a platinum plate was possible using a constant potential method. Applied positive and negative potentials facilitated the in situ extraction and desorption of ions, respectively. Both anions and cations were desorbed into sample aliquot and were determined by ion chromatography (IC). The method was validated using a standard reference material and tested for the determination of the ions in real water samples.     

Diffusion-weighted magnetic resonance imaging in differentiation of postobstructive consolidation from central lung carcinoma

Purpose

To prospectively evaluate diffusion-weighted (DW) magnetic resonance (MR) imaging for differentiation of postobstructive consolidation from centrally located lung carcinomas by using apparent diffusion coefficients (ADCs).

Materials and Methods

An institutional review board approved this study; informed consent was obtained from patients. Forty-nine consecutive patients (3 women, 46 men; mean age, 63.6 years; age range, 42–85 years) with lung carcinoma underwent DW MR imaging. Forty patients had central and nine patients had peripheral lung carcinomas. ADC of each lung carcinoma was calculated from DW MR images obtained with two different b values (0, 1000 s/mm²).In the final study group including 27 patients with central lung carcinoma accompanying distal lung consolidation (mean age, 67.2 years; 3 women, 24 men), ADCs of lung carcinomas were statistically compared among cytologic/histologic types and accompanying postobstructive consolidations. Unpaired t test was used for measurable variables with normal distribution, and Kruskal–Wallis variance analysis and Mann–Whitney U tests were used for the measurable variables without normal distribution.

Results

There was no significant difference between mean ADC values of all types of carcinomas (P=.302) and also between mean ADC values of central (1.91 ± 0.7×10⁻³ mm²/s) and peripheral carcinomas (1.58 ± 0. 6×10⁻³ mm²/s) (P=.224). The mean ADC value for the masses of central lung carcinoma with postobstructive consolidations was 1.83 ± 0.75×10⁻³ mm²/s, and for consolidation was 2.50 ± 0.76×10⁻³ mm²/s. ADC of central carcinoma masses was significantly lower than that of postobstructive consolidations (P=.003).

Conclusions

ADC values of central lung carcinoma masses appear to be lower than accompanying postobstructive consolidations. ADC values could be considered useful as a differentiating parameter among central lung carcinomas and accompanying postobstructive consolidations.     

Bioapplications of poly(amidoamine) (PAMAM) dendrimers in nanomedicine

Poly(amidoamine) (PAMAM) dendrimers are a novel class of spherical, well-designed branching polymers with interior cavities and abundant terminal groups on the surface which can form stable complexes with drugs, plasmid DNA, oligonucleotides, and antibodies. Amine‐terminated PAMAM dendrimers are able to solubilize different families of hydrophobic drugs, but the cationic charges on dendrimer surface may disturb the cell membrane. Therefore, surface modification by PEGylation, acetylation, glycosylation, and amino acid functionalization is a convenient strategy to neutralize the peripheral amine groups and improve dendrimer biocompatibility. Anticancer agents can be either encapsulated in or conjugated to dendrimer and be delivered to the tumor via enhanced permeability and retention (EPR) effect of the nanoparticle and/or with the help of a targeting moiety such as antibody, peptides, vitamins, and hormones. Biodegradability, non-toxicity, non-immunogenicity, and multifunctionality of PAMAM dendrimer are the key factors which facilitate steady increase of its application in drug delivery, gene transfection, tumor therapy, and diagnostics applications with precision and selectivity. This review deals with the major topics of PAMAM dendrimers including structure, synthesis, toxicity, surface modification, and also possible new applications of these spherical polymers in biomedical fields as dendrimer-based nanomedicine.     

Temperature dependent energy relaxation time in AlGaN/AlN/GaN heterostructures

The two-dimensional (2D) electron energy relaxation in Al_0.25Ga_0.75N/AlN/GaN heterostructures was investigated experimentally by using two experimental techniques; Shubnikov-de Haas (SdH) effect and classical Hall Effect. The electron temperature (T_e) of hot electrons was obtained from the lattice temperature (T_L) and the applied electric field dependencies of the amplitude of SdH oscillations and Hall mobility. The experimental results for the electron temperature dependence of power loss are also compared with the current theoretical models for power loss in 2D semiconductors. The power loss that was determined from the SdH measurements indicates that the energy relaxation of electrons is due to acoustic phonon emission via unscreened piezoelectric interaction. In addition, the power loss from the electrons obtained from Hall mobility for electron temperatures in the range T_e > 100 K is associated with optical phonon emission. The temperature dependent energy relaxation time in Al_0.25Ga_0.75N/AlN/GaN heterostructures that was determined from the power loss data indicates that hot electrons relax spontaneously with MHz to THz emission with increasing temperatures.     

Broadband circular polarizer based on high-contrast gratings

A circular polarizer, which is composed of periodic and two-dimensional dielectric high-contrast gratings, is designed theoretically such that a unity conversion efficiency is achieved at λ(0)=1.55 μm. The operation is obtained by the achievement of the simultaneous unity transmission of transverse magnetic and transverse electric waves with a phase difference of π/2, meaning that an optimized geometrical anisotropy is accomplished. By the utilization of the rigorous coupled-wave analysis and finite-difference time-domain methods, it is shown that a percent bandwidth of ～50% can be achieved when the operation bandwidth is defined as the wavelengths for which the conversion efficiency exceeds 0.9.