Long-wavelength Ultraviolet A1 and Visible Light Photoprotection: A Multimodality Assessment of Dose and Response

Human skin is exposed to visible light (VL; 400–700 nm) and long-wavelength ultraviolet A1 (UVA1) radiation (370–400 nm) after the application of organic broad-spectrum sunscreens. The biologic effects of these wavelengths have been demonstrated; however, a dose–response has not been investigated. Ten subjects with Fitzpatrick skin phototype IV-VI were enrolled. Subjects were irradiated with 2 light sources (80–480 J cm⁻²): one comprising VL with less than 0.5% UVA1 (VL+UVA1) and the other pure VL. Skin responses were evaluated for 2 weeks using clinical and spectroscopic assessments. 4-mm punch biopsies were obtained from nonirradiated skin and sites irradiated with 480 J cm⁻² of VL+UVA1 and pure VL 24 h after irradiation. Clinical and spectroscopic assessments demonstrated a robust response at VL+UVA1 sites compared with pure VL. Histology findings demonstrated a statistically significant increase in the marker of inflammation (P < 0.05) and proliferation (P < 0.05) at the irradiated sites compared with nonirradiated control. Threshold doses of VL+UVA1 resulting in biologic responses were calculated. Results indicate that approximately 2 h of sun exposure, which equates to VL+UVA1 dose (~400 J cm⁻²), is capable of inducing inflammation, immediate erythema and delayed tanning. These findings reinforce the need of photoprotection beyond the UV range.     

Task Specific Onium Salts and Ionic Liquids as Soluble Supports in Grieco ’s Multicomponent Synthesis of Tetrahydroquinolines

In this work was presented an application of the use of task specific onium salts (TSOSs) as soluble supports in Grieco’s multicomponent synthesis of tetrahydroquinolines. These soluble supports are of wide applicability and combine advantages of solid phase synthesis without its limitations with those of solution phase chemistry. After a simple washing step, products were cleaved from the supports and obtained in pure form and good yields.     

Analysis of anions by solid-state spot-tests

Trituration and capillary solid-state spot-tests for 25 anions with a number of organic and inorganic reagents have been examined. A comparative study of the corresponding reactions in solution has also been made. Incorporation of a glass-wool plug in the capillary improves the selectivity. Schemes are presented for possible use of the technique.     

An electrolytic device for preparation of hydrogen and oxygen from water for isotopic analysis

An electrolytic device for decomposition of water has been developed which readily gives hydrogen and oxygen for isotopic measurement with a mass spectrometer. A 20-mul sample can be decomposed quantitatively in 10 min with good reproducibility. The results produced are comparable with those obtained by reduction with uranium.     

Soft-laser scanning densitometry performed on a 35-mm slide illustrating SDS-PAGE separation of adenovirion polypeptides

Virion polypeptides (35 S), methionine-labeled and purified by CsCl gradient centrifugation, were separated by SDS-gel electrophoresis. Analysis of their band pattern was performed by scanning the images of the SDS-gels shown on a 35-mm slide. The densitometric tracings revealed the presence of 17 protein bands, although only 15 of them were visible to the naked eye. The high sensitivity and resolving capacities of the soft-laser scanning densitometer enabled us to detect trace amounts of protein bands separated in SDS-gels and to obtain a resolution compatible to that of electrophoresis. Fourfold electronic amplification of the densitometric tracings, produced by a computer, generated new information regarding the pattern of the electrophoregram. The facility to amplify peaks of importance is particularly advantageous when faint or overlapping protein bands revealed on a gel are assessed.     

Natural and fallout radionuclide concentrations in the environment of Islamabad

A study on the concentration of natural and fallout radionuclides in environmental samples collected from different localities of Islamabad was performed. For the determination of gamma-emitters such as ²³⁸U, ²³²Th, ⁴⁰K and ¹³⁷Cs high purity germanium (HPGe) detector was used while for the analysis of ⁹⁰Sr, a beta-emitter, liquid scintillation counting system was used. The indoor absorbed dose rate was measured by a CaF₂ : Dy thermoluminescence detector. Other radiation parameters were also determined to evaluate the radiation hazard. All the results were well within the permissible limits showing that there is no radiation hazard in the environment of Islamabad.     

Heterocyclic synthesis via enaminones: Novel synthesis of (1H)‐pyridin‐2‐one,pyrazolo[1,5‐a]pyrimidine and isoxazole derivatives incorporating a N‐methylphthalimide and their biological evaluation

Novel synthesis of (1H)‐pyridin‐2‐one, pyrazolo[1,5‐a]pyrimidine and isoxazole derivatives incorporating N‐methylphthalimide moiety are reported. Reaction of enaminone 2 with malononitrile affords 4. Condensation of 2 with cyanothioacetamide or benzoylacetonitrile affords compounds 6 and 7 respectively. Reaction of 2 with hydrazine hydrate afford 2,3‐dihydrophthalazine‐1,4‐dione ( 10 ). Condensation of 2 with hydroxylamine and 3‐aminopyrazole derivatives affords compounds 12 and 15a,b respectively. Antimicrobial and antifungal activity were determined for representative compounds and most of them showed moderate activity as antimicrobial agents, while compounds 2 and 7 show strong activity against Aspergillus niger. The structure of the newly synthesized compounds was elucidated by elemental analyses and ¹H nmr spectra and some cases by ¹³C nmr investigation.     

汞(II)与牛血红蛋白相互作用的研究

本文采用紫外光谱(UV/VIS)、荧光光谱和圆二色谱等方法,对汞(II)与牛血红蛋白(BHb)的相互作用进行了研究。结果表明:Hg2 处理导致BHb紫外吸收的增加,出现LMCT带,并随Hg2 浓度的增加LMCT带强度显著增强。BHb分子中Soret带的吸收随着Hg2 作用时间的增加而持续降低,表明Hg2 使部分血红素辅基从BHb中脱离出来。蛋白内源荧光光谱显示,Hg2 与BHb的结合会影响蛋白质的三级结构和四级结构。远紫外圆二色谱表明,Hg2 处理会导致BHb蛋白的α-螺旋含量减少。     

Structure determination of bioactive galloyl derivatives by NMR spectroscopy

The investigation of the chemical constituents of Symplocos racemosa Roxb led to the isolation of two new glycosides, symcomoside A (1) and symcomoside B (2), together with one known glycoside, tortoside C (3), which is reported for the first time from this plant. The structures of the new compounds were determined by 1D and 2D homonuclear and heteronuclear NMR spectroscopy, from chemical evidence and by comparison with published data for closely related compounds. Symcomoside B (2) showed potent inhibitory activity against alpha-glucosidase in a concentration-dependent fashion with an IC50 value of 0.733 +/- 0.033 mM whereas symcomoside A (1) showed very weak inhibitory activity against alpha-glucosidase (9.90% in 0.70 mM).