Experimental central nervous system phaeohyphomycosis following intranasal inoculation of Xylohypha bantiana in cortisone-treated mice

Experimental central nervous system (CNS) phaeohyphomycosis was established in cortisone-treated mice following intranasal exposure to conidia of Xylohypha bantiana (Cladosporium bantianum, C. trichoides). X. bantiana was recovered from the lungs of 78% of intranasally inoculated normal mice sacrificed within the first 3 days of infection and from 15% at day 28. The fungus was not recovered from the brains of normal mice. In contrast, X. bantiana was recovered from only 33% of the lungs of cortisone-treated mice within the first 3 days of infection. However, the fungus was recovered from the brains of 11% of cortisone-treated mice sacrificed or dying over a 28 day period. Histologically and temporally the CNS disease in cortisone-treated, intranasally inoculated mice was consistent with hematogenous dissemination from a primary pulmonary focus.     

Proton conduction in bacteriophodopsin via a hydrogen-bonded chain with large proton polarizability

A Corey-Pauling-Kolthun molecular model of bacteriorhodopsin was built. This model shows that a largely structurally symmetrical hydrogen bonded chain asp, 6 tyr, glu may be formed. With regard to the total proton potential this chain shows very large proton polarizability and thus via this chain the positive charge can be conducted to the outside of the membrane via a Grotthus mechanism.     

Studies of the specific role of the subunits of choriogonadotropin for biological, immunological and physical properties of the hormone. Digestion of choriogonadotropin and its isolated subunits with serine carboxypeptidase

The residues 90-92 can be split off from the C-terminal region of the isolated alpha-subunit of choriogonadotropin (residues 88--92: -Tyr-Tyr-His-Lys-Ser-OH) by means of serine carboxypeptidase (des-Lys91,Ser92-alpha-subunit; des-(90-92)-alpha-subunit). However, when choriogonadotropin is digested by serine carboxypeptidase, only the residues 143-145 (-Leu-Pro-Gln-OH) form the C-terminus of the beta-subunit are released (des-(143-145)-choriogonadotropin). Depending on the pH conditions, glutamine 145 and the residues 143-145, respectively, are liberated by digestion of the isolated beta-subunit (des-Gln145-beta-subunit and des-(143-145)-beta-subunit, respectively). The present study provides evidence that the C-termini of both the isolated subunits and those in choriogonadotropin are probably arranged on the surface of the molecules. The biological activity of des-(143-145)-choriogonadotropin is not significantly decreased. The immunological activity, however, is reduced when measured by complement fixation. In comparison to the native hormone, a four-fold amount of des-(143-145)-choriogonadotropin has to be applied to obtain highest complement fixation. The conformation of des-(143-145)-choriogonadotropin does not seem to differ from that of the native hormone, when estimated both by CD measurements and by Ans-choriogonadotropin fluorescence. The respective determinant therefore seems to depend, at least to some extent, on the sequence of the C-terminal region of the beta-subunit of the hormone; complement fixation, however, does not seem to be affected significantly, when the des-(143-145)-beta-subunit is compared with the native beta-subunit using an antiserum against the native beta-subunit. This provides evidence that this C-terminal determinant is possibly more immunogenic at the hormone than at the isolated beta-subunit. The biological activity of recombined choriogonadotropin in vivo as well as in vitro is markedly reduced when serine 92 is removed from the C-terminus of the alpha-subunit (des-Ser92,Lys91-alpha-native beta-subunit: 36% residual activity in vivo). Biological activity is lost when the residues 88-90 are removed by digestion of the des-Ser92,Lys91-alpha-subunit with carboxypeptidase A. Recombination products between a modified alpha-and the native beta-subunit show a reduced Anschoriogonadotropin fluorescence (des-Lys91,-Ser92-alpha + native beta-subunit: 52%; des-(88-92)-alpha- + native beta-subunit: 23%). The Ans-induced aggregation of choriogonadotropin, however, also takes place in those recombination products which display a low Ans-choriogonadotropin fluorescence, indicating that the reduction is probably not caused by a portion of the molecules losing their binding sites for Ans. Therefore the diminished Ans-choriogonadotropin fluorescence seems to signal small conformational changes. The CD spectra of the native and the des-(90-92)-alpha-subunit, however, seem not to differ significantly. It is shown that the release of amino acids from the C-terminus of the alpha-subunit causes a disturbance of the interaction between the subunits. This seems to prevent an effective conformational change of the beta-subunit which probably is a prerequisite for the binding of the hormone to the receptors of Leydig cells.     

Effect of sensory stimulation applied under the great toe on postural ability in patients with fibromyalgia

Abstract

Fibromyalgia (FM) is a chronic pain syndrome, characterised by several symptoms. One of the most prevalent symptoms in FM is balance impairment that compromise the autonomy, function and performance status of patients.

Purpose: The main objective of the present study was to evaluate the effect of sensory stimulation provided by the use of a low additional thickness of 0.8?mm placed under the great toes bilaterally on the centre of pressure (CoP) measures in patients with FM. It was hypothesised that postural ability would change with a low focal additional thickness used to compute these measures.

Materials and Method: Twenty-four patients with FM voluntarily participated in this study. Postural performance during quiet standing was investigated through the CoP displacements recorded using a force-plate. Sensory stimulation was provided by a small additional thickness of 0.8?mm placed under the great toe bilaterally and two conditions were compared: additional thickness 0 (control) and 0.8?mm.

Results: An improvement of body balance through spatial parameters with sensory cutaneous stimulation applied under the great toe bilaterally were observed in patients with FM. Our results showed a significant decrease of surface area and mean speed of CoP, associated to a significant decrease of variance of speed. An additional observation is that sagittal (Y) mean position of the CoP gets more anterior (+ 5?mm) relative to control condition.

Conclusion: These findings brings new clinical perspectives in the development of intervention strategies in the management of patients with FM and balance disorders, completing validated therapeutic strategies.     

Membrane Particle Distribution in the Sternal Epithelia of the Terrestrial Isopod Porcellio scaber Latr. (Crustacea, Oniscidea) during CaCO3 Deposit Formation and Resorption, a Freeze-Etch Analysis

The anterior sternal epithelium of terrestrial isopods transports cuticular Ca²⁺ to and from large sternal CaCO₃ deposits. We analyzed the anterior and posterior sternal epithelium by the means of the freeze-etch technique and measured the size distribution and density of intramembrane particles (IMPs) during three different molting stages. At least three IMP size classes around 4.5, 7.7, and 9.4 nm can be distinguished on the P-face of the apical and basolateral plasma membrane. An additional size class of around 12.8 nm is restricted to the apical compartment. In the anterior sternal epithelium, the density of these large particles changes by a factor of 1.9 during the molt cycle, suggesting a role in CaCO₃ formation and/or resorption. The density of the smaller IMPs rises transiently by a factor of 1.3 in the posterior sternal epithelium only. The IMP density of the basolateral plasma membrane increases significantly by a factor of 1.4 and 1.3 in the anterior and posterior sternal epithelia, respectively. The results indicate that increases in the IMP density contribute to the differentiation to an increased transport activity during the cyclic enlargements of the plasma membrane surface area in the anterior sternal epithelium.