Several Drosophila genes involved in the control of segmentation and segment identity share a 183-bp conserved sequence termed homeo box. Homeo box sequences have been detected and cloned from the genomes of insects like Drosophila to vertebrates such as mouse and man. Two chicken homeo box genes CHox1 and CHox3, are described. Cloning of the CHox1 and CHox3 homeo boxes was performed using Drosophila and murine homeo box sequences as probes under low-stringency conditions. Analysis of both chicken homeo box sequences revealed them to be homeo boxes that have diverged from the Antennapedia class with homologies to homeo boxes of other organisms in the range of 75-42% at the nucleotide level and 69-41% at the protein level. Analysis of CHox3 expression during early embryo development showed that the gene codes for five transcripts 1.3, 1.9, 2.6, 5.6 and 7.9 kb in size. Three of the transcripts (1.3, 1.9 and 5.6 kb) are also recognized by a flanking non-homeo box containing probe. The levels of the different transcripts changed during the first five days of development. The most abundant transcripts (1.3 and 1.9 kb) are already present at the time the egg is laid. Their transcription peaks at day 1 of incubation and then decreases. The CHox1 transcripts are present at very low levels between days 2.5 and 4 of development. These two chicken genes represent bona fide Hox genes in a branch of vertebrates that evolved parallel to mammals.
A storage-stable lyophilized collagen product comprises acid-sol. purified native collagen in combination with platelet growth factors. A pharmaceutical compn. for enhancing wound healing comprises an aq. soln. of water sol. acid-sol. purified native collagen and platelet derived growth factors. [on SciFinder(R)]
The parameters affecting simple coacervation and the ability to encapsulate oleic acid using this technique were investigated. Coacervation was achieved using different types of gelatin (bloom no., charge) and various electrolytes. The electrolytes used for the coacervation can be divided into 3 groups: (1) inert salts; (2) phase sepn. inducers, (a) pptn. inducing agents (PIA), and (b) coacervation inducing agents (CIA); and (3) coacervation inhibiting agents. The encapsulation of oleic acid was evaluated with two types of gelatin and various emulsifiers (anionic, cationic, and nonionic). For pos. charged gelatin, the encapsulation is incomplete in presence of cationic emulsifiers. For neg. charged gelatin no general trend was obsd. The stirring rate for each step of the prepn. of the microcapsules was evaluated. High stirring is essential only in the cooling stage. The study was carried out in view of encapsulation of particular bacteria dispersed in the oil phase. [on SciFinder(R)]
It has been shown in vitro that verapamil inhibits parathyroid hormone-induced bone resorption. To determine the effect of verapamil administration on bone histology in rats with chronic renal failure, male Wistar rats were divided into three groups: subtotally nephrectomized (SNX), SNX treated with verapamil, 8 mg/kg/day p.o. (SNX-V) and control (C). Thirteen weeks later, the mandibular condyle bone was studied by histomorphometry. When compared to C rats, SNX rats had active bone disease, with increased resorption parameters (resorption surface, active resorption surface, osteoclast number) and accelerated mineral appositional rate. These parameters improved with verapamil administration. When compared to C rats, SNX-V rats had decreased osteoid seam width and mineral appositional rate. Serum parathyroid hormone was similarly elevated in both uremic groups. These data suggest that verapamil administration improves active bone disease in rats with chronic renal failure and decreases bone formation.
The effects of surface active agents on pellet formation in the filamentous bacterium Streptomyces tendae were investigated. Addn. of Pluronic F68 or Brij 58 at inoculation to the fermn. medium (up to 0.1% wt./wt.) induced cellular aggregation. Below this concn., the av. pellet size increased with increasing surfactant concn. Above this point inhibition of pellet formation was obsd. Both surfactants caused aggregation of dispersed mycelia when added after fermn. [on SciFinder(R)]
Enhancement of emulsifying properties of a model protein, ovalbumin, was achieved by covalent attachment of hydrophobic groups using various esters of N-hydroxysuccinimide. The resulting modified proteins were much better emulsifiers than the native ovalbumin, even at low modification degree (20-30% of available amine groups): in tetradecane-water emulsions oil sepn. was obsd. within a few hours, when 0.7 mg/mL native ovalbumin was used, compared to ∼1 mo. until sepn. was obsd. when the modified proteins were used . The use of highly modified proteins prevented completely oil sepn. (≥2 mo.); for example, emulsions prepd. with 81% modified proteins with C8 or C6, showed no change in droplet size distribution even 50 days after prepn. The effect of chain length on emulsification was also investigated: an optimal chain length (C8) was found, for both low and high modifications. [on SciFinder(R)]
A review with 110 refs. on photosensitized regeneration of NAD(P)H cofactors by photochem. means. Reductive regeneration of NAD(P)H cofactors proceeds through coupling of photogenerated N,N'-dimethyl-4,4'-bipyridinium radical cation, which acts as electron carrier, to the enzymes lipoamide dehydrogenase, LipDH and ferredoxin reductase, FDR, resp. Regeneration of NAD(P)H is also accomplished by substitution of the enzymes and electron carrier by synthetic rhodium complexes acting as H-donors for the regeneration of NAD(P)H. Oxidn. of NAD(P)H proceeds either by reductive quenching of the excited photosensitizer by NAD(P)H or dark oxidn. of NAD(P)H by the oxidized photoproduct formed in the photosensitized electron-transfer process. The systems are applied in the dehydrogenation of alcs., hydroxy acids, and amino acids. [on SciFinder(R)]
