Intermediate filament proteins and epithelial differentiation in the embryonic ovary of the rat

Abstract. The development and sexual differentiation of gonads in female rat embryos and fetuses between the ages of 11 and 17 days was studied by immunocytochemical analysis of intermediate filament proteins and laminin by light and electron microscopy. In the 11-day-old pregonadal embryo, the surface epithelial cells in the ventral cortex of the mesonephros contained desmin but not cytokeratin or vimentin. The development of the gonad began on the following day by proliferative growth of the mesonephric surface cells, which like the subepithelial cells soon expressed vimentin in addition to desmin. The differentiation continued by formation of separate epithelial cell clusters, which joined into cords, irregular in shape and size. Desmin disappeared from the cord cells and cytokeratins appeared while vimentin remained in all somatic cell types. Desmin was especially abundant in some stromal cells adjacent to the epithelial tissues. After the segration of the basic ovarian tissues, vimentin and desmin decreased and cytokeratins appeared in the surface epithelial cells. New changes in cytokeratin expression appeared with the differentiation of the embryonic cords in a sex-specific manner with gradual decrease of reactivity for cytokeratin 18. No immunoreaction to the neurofilament proteins was found at the present ages, and the germ cells were negative for intermediate filaments. The results show that desmin is expressed in several primitive ovarian and mesonephric cells even though they are not myogenic. The sexual differences emerge after the incipient formation of the genetically female gonad, as different organization of the internal epithelial tissue with different timing of changes in intermediate filament proteins when compared with the male gonad.     

Mineralization of carbon and nitrogen in soil samples taken from three fertilized pine stands: Long-term effects

Seven years after fertilization the rate of CO₂ production in the soil samples taken from the organic horizons of a poor pine forest site (Calluna vulgaris site type), treated with urea or ammonium nitrate with lime, was lower than that in the unfertilized soil. The same trend was also observed in samples of theEmpetrum-Calluna site type 14 years after fertilization. In the more fertileVaccinium myrtillus site type these rapidly-soluble N fertilizers had a long-term enhancing effect on the production of CO₂. Apatite and biotite eliminated the decreasing effect of urea on the production of CO₂. One reason for this might be the long-term increase in soil pH caused by apatite and biotite, or their constituents (Ca, Mg, K, P). Nitroform (a slow-releasing N fertilizer) had no statistically significant effect on the production of CO₂ in soil samples from any of the forest types. Despite the high N mineralization in the samples from nitroform fertilized soils there was no nitrification, and the high content of total N indicated that after nitroform fertilization the losses of N were low.The correlation between the net mineralization values for C (CO₂ production) and N was poor. However, multiple linear regression analysis, which also took into account the effect of nutrients and pH, indicated that there was a link between the mineralization of C and N.     

Proteomic analysis of aneuploid lines in the homeologous group 1 of the hexaploid wheat cultivar Courtot

Three monosomic lines (MSLs) and three nullisomic lines (NSLs) of the homeologous group 1 and one euploid line of the bread wheat Triticum aestivum cultivar Courtot were used in a proteomic approach to investigate the effects of zero, one or two doses of chromosomes 1A, 1B and 1D on the amount of endosperm proteins. Polypeptides whose amounts changed significantly between each aneuploid line and the euploid line were identified using image analyses of two-dimensional gel electrophoresis patterns resulting from specific endosperm protein extractions. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and electrospray ionization tandem mass spectrometry were also used for protein identification. Removing one chromosome or a chromosome pair allowed varying responses to be observed for the remaining endosperm protein genes. Compensation phenomena for the high molecular weight glutenin subunits (HMW-GS) were detected only in the MSLs. Subunits Bx7, By8 and Dy12 were the only HMW-GS overexpressed (from 152-737%) when chromosomes 1A or 1B or 1D were at hemizygous state. Thirteen new protein spots were detected only in the NSL1D, and seven were identified as HMW-GS analogs. These seven new spots may result from the expression of inactive genes. The HMW-GS were of significantly higher volume in MSLs, whereas the low molecular weight glutenin subunits and the gamma-gliadins were of lower volume in aneuploid lines. Most of the down-regulated proteins in the MSLs were storage proteins encoded at loci located on another chromosome pair. Complex regulations between chromosomes and loci of the homeologous groups 1 and 6 in bread wheat are discussed.     

Urate Crystal Induced Inflammation and Joint Pain Are Reduced in Transient Receptor Potential Ankyrin 1 Deficient Mice – Potential Role for Transient Receptor Potential Ankyrin 1 in Gout

IntroductionIn gout, monosodium urate (MSU) crystals deposit intra-articularly and cause painful arthritis. In the present study we tested the hypothesis that Transient Receptor Poten-tial Ankyrin 1 (TRPA1), an ion channel mediating nociceptive signals and neurogenic in-flammation, is involved in MSU crystal-induced responses in gout by utilizing three experi-mental murine models.MethodsThe effects of selective pharmacological inhibition (by HC-030031) and genetic depletion of TRPA1 were studied in MSU crystal-induced inflammation and pain by using 1) spontaneous weight-bearing test to assess MSU crystal-induced joint pain, 2) subcutaneous air-pouch model resembling joint inflammation to measure MSU crystal-induced cytokine production and inflammatory cell accumulation, and 3) MSU crystal-induced paw edema to assess acute vascular inflammatory responses and swelling.ResultsIntra-articularly injected MSU crystals provoked spontaneous weight shift off from the affected limb in wild type but not in TRPA1 knock-out mice referring alleviated joint pain in TRPA1 deficient animals. MSU crystal-induced inflammatory cell infiltration and accumulation of cytokines MCP-1, IL-6, IL-1beta, MPO, MIP-1alpha and MIP-2 into subcu-taneous air-pouch (resembling joint cavity) was attenuated in TRPA1 deficient mice and in mice treated with the selective TRPA1 inhibitor HC-030031 as compared to control animals. Further, HC-030031 treated and TRPA1 deficient mice developed tempered inflammatory edema when MSU crystals were injected into the paw.ConclusionsTRPA1 mediates MSU crystal-induced inflammation and pain in experimental models supporting the role of TRPA1 as a potential mediator and a drug target in gout flare.     

Assessment of exposure to intermediate frequency electric fields and contact currents from a plasma ball

While electric fields at intermediate frequencies are not widely utilized for industrial technologies, surprisingly, certain toys emit the highest electric fields found in our living environment. These toys, plasma balls, are devices that use high voltage to create ionized light discharges. In this study, we assessed exposure to electric fields and contact/induced current from a recreational plasma ball device. The electric field strength was measured as a function of distance from the device, and the contact/induced current was measured with a current clamp in different exposure situations with point or grasping contact. The characteristic spectra of the electric field and contact current were measured, and both the multiple frequency rule and weighting of the spectra were applied according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 1998 and 2010 guidelines. The results indicate that the recommended reference levels for the general public are exceeded at distances <1.2 m, and that the contact currents in the hand may be twice higher than recommended by the general public guidelines.