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A small irregular coccoid methanogenic bacterium (PA T ) was isolated from the hindgut of the cockroach Periplaneta americana. Fluorescence microscopy and transmission electron microscopy of the hindgut of P. americana suggest that the organism occurs abundantly in the microbiota attached to the hindgut wall. The strain produces methane by the reduction of methanol and methylated amines with molecular hydrogen. Acetate, coenzyme M, yeast extract, tryptic soy broth and vitamins are required for growth. The cells lack a rigid cell wall and lyse immediately in buffers of low ionic strength. Maximum rate of growth (specific growth rate, 022 h V1 ) occurs in a rich medium at 39 SC, at a pH range of 72-77 and at a salt concentration below 100 mM NaCl. Sequence analysis of the small-subunit rDNA indicates that strain PA T is related to the family Methanosarcinaceae but does not belong to any previously described genus. Therefore, it is proposed that strain PA T be classified in a new genus, related to the Methanosarcinaceae, as Methanomicrococcus blatticola (type strain PA T l DSM 13328 T ).

Amorphous solid dispersions (ASDs) represent a promising formulation approach for poorly soluble drugs. We explored the formulation-related impact of ASDs on permeation rate, apparent solubility and molecular solubility of the poorly soluble drug ABT-102. The influence of fasted state simulated intestinal fluid (FaSSIF) as dispersion medium was also studied. ASDs were prepared by hot-melt extrusion. Permeation rate was assessed by the Caco-2 transwell assay. Cell viability and barrier integrity were assured by AlamarBlue©, TEER and permeability of the hydrophilic marker carboxyfluorescein. Apparent solubility and molecular solubility were evaluated by using centrifugation and inverse dialysis, respectively. The in vitro permeation rate of ABT-102 from aqueous dispersions of the ASD was found 4 times faster than that from the dispersions of the crystals, while apparent solubility and molecular solubility of ABT-102 were increased. Yet, a further increase in apparent solubility due to micellar solubilization as observed when dispersing the ASD in FaSSIF, did not affect molecular solubility or permeation rate. Overall, a good correlation between permeation rate and molecular solubility but not apparent solubility was seen.

The lateral compound eye of Scutigera coleoptrata was examined by electron microscopy. Each ommatidium consists of a dioptric apparatus, formed by a cornea and a multipartite eucone crystalline cone, a bilayered retinula and a surrounding sheath of primary pigment and interommatidial pigment cells. With reference to the median eye region, each cone is made up of eight cone segments belonging to four cone cells. The nuclei of the cone cells are located proximally outside the cone near the transition area between distal and proximal retinula cells. The connection between nuclear region and cone segment is via a narrow cytoplasmic strand, which splits into two distal cytoplasmic processes. Additionally, from the nuclear region of each cone cell a single cytoplasmic process runs in a proximal direction to the basement membrane. The bilayered rhabdom is usually made up of the rhabdomeres of 9-12 distal retinula cells and four proximal retinula cell. The pigment shield is composed of primary pigment cells (which most likely secrete the corneal lens) and interommatidial pigment cells. The primary pigment cells underlie the cornea and surround, more or less, the upper third of the crystalline cone. By giving rise to the cornea and by functioning as part of the pigment shield these pigment cells serve a double function. Interommatidial pigment cells extend from the cornea to the basement membrane and stabilise the ommatidium. In particular, the presence of cone cells, primary pigment cells as well as interommatidial pigment cells in the compound eye of S. coleoptrata is seen as an important morphological support for the Mandibulata concept. Furthermore, the phylogenetic significance of these cell types is discussed with respect to the Tetraconata.