Skin Microbiome Compositional Changes in Atopic Dermatitis Accompany Dead Sea Climatotherapy

Dead Sea climatotherapy (DSC) is a well‐established therapeutic modality for the treatment of several diseases, including atopic dermatitis. Skin microbiome studies have shown that skin microbiome diversity is anticorrelated with both atopic dermatitis severity and concurrent Staphylococcus aureus overgrowth. This study aimed to determine whether DSC induces skin microbiome changes concurrent with clinical improvements in atopic dermatitis. We sampled 35 atopic dermatitis patients and ten healthy controls on both the antecubital and popliteal fossa. High‐resolution microbial community profiling was attained by sequencing multiple regions of the 16S rRNA gene. Dysbiosis was observed in both lesional and nonlesional sites, which was partially attenuated following treatment. Severe AD skin underwent the most significant community shifts, and Staphylococcus epidermidis, Streptococcus mitis and Micrococcus luteus relative abundance were significantly affected by Dead Sea climatotherapy. Our study highlights the temporal shifts of the AD skin microbiome induced by Dead Sea climatotherapy and offers potential explanations for the success of climatotherapy on a variety of skin diseases, including AD.     

Fullerenes inside carbon nanotubes and multi-walled carbon nanotubes: optimum and maximum sizes

The potential energies of interaction between carbon nanotubes and internal fullerenes of spherical and ellipsoidal shape, as well as between nanotubes in multi-walled nanotubes were calculated using the Lennard–Jones (LJ) potential for carbon–carbon interactions. The optimum and maximum size of internal fullerenes and multi-walled nanotubes are determined as a function of the external nanotube radius. It was found that at the potential energy minimum, the van der Waals distance is close to that in graphite for all studied cases. The calculated results agree with available experimental observations and could be used as a guide for future experiments.     

Magnetic properties of Co-ferrite-doped hydroxyapatite nanoparticles having a core/shell structure

The magnetic properties of Co-ferrite-doped hydroxyapatite (HAP) nanoparticles of composition Ca_10−3xFe_2xCo_x(PO₄)₆(OH)₂ (where x=0, 0.1, 0.2, 0.3, 0.4 and 0.5% mole) are studied. Transmission electron microscope micrograms show that the 90 nm size nanoparticles annealed at 1250 °C have a core/shell structure. Their electron diffraction patterns show that the shell is composed of the hydroxyapatite and the core is composed of the Co-ferrite, CoFe₂O₄. Electron spin resonance measurements indicate that the Co²⁺ ions are being substituted into the Ca(1) sites in HAP lattice. X-ray diffraction studies show the formation of impurity phases as higher amounts of the Fe³⁺/Co²⁺ ions which are substituted into the HAP host matrix. The presence of two sextets (one for the A-site Fe³⁺ and the other for the B-site Fe³⁺) in the Mössbauer spectrum for all the doped samples clearly indicates that the CoFe₂O₄.cores are in the ferromagnetic state. Evidence of the impurity phases is seen in the appearance of doublet patterns in the Mössbauer spectrums for the heavier-doped (x=0.4 and 0.5) specimens. The decrease in the saturation magnetizations and other magnetic properties of the nanoparticles at the higher doping levels is consistent with some of the Fe³⁺ and Co²⁺ which being used to form the CoO and Fe₂O₃ impurity phase seen in the XRD patterns.     

Reinvestigation of dimerization of Z-N-alkylarylmethylideneindoxyls upon exposure to UV-vis radiation

Russian Chemical Bulletin - N-Alkyl-2-arylmethylideneindoxyls upon exposure to UV or visible light undergo dimerization not to cyclobutane adducts as it has been reported earlier, but to...     

Molecular structure of the cobalt(ii) chloride complex with triphenyl-N-(2-pyrimidyl)phosphineimine

An X-ray structural study of the cobalt(ii) chloride complex with triphenyl-N-(2-pyrimidyl)phosphineimine has been performed (automatic diffractometer, Mo-–K , 2916 observed reflections, the heavy-atom method, the least squares method in anisotropicisotropic approximation toR=0.043). The crystals are monoclinic,a=15.979(6) Å,b=17.391(6) Å,c=14.976(6) Å, =104.21(2)°,V=4034(5) ų,d _calc=1.384 g cm^–3,Z=4, space groupP2₁/c. The Co atom has a distorted tetrahedral coordination by two Cl atoms (2.268(2) Å and 2.278(3) Å) and two N atoms (2.030(4) Å and 2.025(5) Å) of the two pyrimidine heterocycles. The Cl-Co-Cl and N-Co-N bond angles are equal to 107.7(1)° and 123.4(2)°, respectively. Additional weak coordination of the Co atom by two N atoms of the imine groups [Co...N 2.982(4) Å and 3.045(4) Å] is also observed in the molecule of the complex, and this coordination changes the nearest environment of the Co atom to distorted octahedral coordination. The lengths of the phosphorus-imine P=N bonds are 1.596(6) Å and 1.585(6) Å. The results obtained are compared with previous structural investigations of similar complexes of transition metals with iminophosphoranes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1203–1206, July, 1993.     

One-dimensional statistical mechanics models with application to peapods

Quasi one-dimensional systems of molecules of C₆₀ encapsulated in (10/10) nanotubes were studied by both lattice-gas and Takashi–Gursey configurational integral methods of statistical mechanics for both open and capped finite nanotubes as well as infinite nanotubes. From well-established potentials, the energy, heat capacity compressibility, equation of state and absorption isotherms were computed as a function of temperature and molecular density. The existing theories were extended to include the calculation of clustering, and the number of clusters as a function of size was computed for a variety of temperatures and densities. For both models, all molecules are frozen into a single cluster, and increasing the temperature results in a break-up into smaller clusters. The corresponding heat capacity has a broad maximum, which is lower for the T–G model than for the lattice-gas model. The equations of state have a similar form in both models and are identical at low temperatures. The absorption isotherms show that filling of the tubes can take place at all temperatures of practical interest. Peapods are nearly ideal realizations of one-dimensional systems whose thermodynamic and structural properties can be accurately obtained by statistical mechanics. Received: 15 November 2001 / Accepted: 25 October 2002 / Published online: 10 March 2003 RID="*" ID="*"Corresponding author. Fax: +1-215/573-2128, E-mail: lag@sol1.lrsm.upenn.edu RID="**" ID="**"Present address: Dept. of Physics, North Carolina State University, Raleigh, NC 27695, USA     

Enhancement of the hydrophobicity of silk fabrics by SF6 plasma

Hydrophobic properties are of interest in fabric and textile manufacture. We have used radio-frequency inductively coupled SF₆plasma to modify the surface of Thai silk fabrics for the enhancement of the hydrophobic property. The water contact angle of fabrics increased from 0°up to 145°after SF₆ plasma treatment. The measured water absorption time was found to depend upon the treatment time and RF power, for SF₆ pressures lower than 0.05 Torr. At higher SF₆ pressures, all samples achieved absorption times in excess of 200 min, regardless of the treatment time and RF power. The morphology changes of fabrics after plasma treatment were characterized by scanning electron microscopy and atomic force microscopy. After plasma treatment, the RMS surface roughness of the fibres increased from about 10 to 30 nm. From X-ray photoelectron microscopy analysis, we found that the hydrophobicity of the fabrics is the highest when the fluorine/carbon ratio at the surface increases. A small decrease of the oxygen/carbon ratio was also observed on the fabrics that showed the longest absorption times.