Prostaglandin Metabolism during Cell Aggregation in the Regenerating Vertebrate Appendage

Prostaglandin metabolism during cell aggregation period was studied in the regenerating tail of the house lizard. On the basis of scanning electron microscopy it was observed that similar kinds of cells in the blastema aggregate to form promuscie aggregate and procartilage aggregate on the 13th day of tail regeneration. In order to understand the prostaglandin metabolism the following parameters were analysed. Fatty acid composition of phospholipids and free fatty acids analysed by gas chromatography. The activity of two rate limiting enzymes-phosholipase A and C, and the activity of the enzymes which are responsible for the oxygenation of polyunsaturated fatty acids-lipoxygenase and cycloxygenase were also estimated. The characterization of the endogenous prostaglandins were carried out by high performance liquid chromatography. On the basis of the above investigations, we observed an increase in phospholipase C activity and resultant increase in free arachidonic acid level. High activity of cycloxygenase and presence of prostaglandin E2 (PGE2) were also observed PGE2 was reported to stimulate cAMP production and resultant cell differentiation. These observations suggest the involvement of prostaglandin metabolism during cell aggregation period in the regenerating blastema and resultant cytodifferentiation of blastemal cells.     

Megaoesophagus in the mouse: histochemical and ultrastructural studies

Histochemical and ultrastructural studies of the muscle coat of the oesophagus from ICRC/HiCri mice (with megaoesophagus) and DBA/2fNCri mice (normal oesophagus) were carried out. The striking observation from histochemical studies was the presence of smooth muscle in the abdominal segment of the oesophagus from ICRC mouse in contrast to the control strain where smooth muscle was present only in the lowermost portion adjoining the stomach. Ultrastructural studies of the oesophageal wall from 5- and 10-day-old ICRC mice revealed an apparently normal muscle coat. In 3-month-old ICRC mice the upper abdominal segment of the oesophagus showed several abnormalities of smooth muscle fibres and paucity of plexus tissue accompanied by interstitial collagen deposition. The abnormalities were more severe in 1-year-old animals and were seen throughout the abdominal segment. From this study it is suggested that the primary cause of megaoesophagus in ICRC mice is neurogenic and not myogenic.     

Papillary cystic neoplasm of the pancreas. Report of a case diagnosed by fine needle aspiration cytology

Fine needle aspiration (FNA) performed on a young woman who presented with a mass in the left hypochondrium yielded fluid. Smears and Cytospin preparations of the fluid showed good cellularity, consisting of relatively monomorphic cells forming a perivascular papillary pattern. FNA cytology thus suggested a diagnosis of papillary cystic neoplasm of the pancreas. Surgical removal of the pancreatic tumor and detailed histologic study confirmed the cytologic diagnosis.     

Studies of the male reproductive system of the amphipod Orchestia platensis Kr?yer (Crustacea: Amphipoda)

Morphological details of the testis, seminal vesicles and vas deferens of Orchestia platensis are described. The follicular lumen of the mature testis contains spermatogonia, spermatocytes, spermatids and spermatozoa. The histochemical nature of the testis and the vas deferens is elucidated. The spermatozoa and vas deferens contain acid sulphated mucopolysaccharides and neutral mucopolysaccharides. In addition, they contain basic proteins, disulphide groups, lipids, phospholipids, RNA and DNA.     

The Influence of Some Phenolic Compounds on Nodulation in Pigeonpea (Cajanus cajan(L.) Millsp.)

Studies on exogenous application of phenolic compoundsviz: p-hydroxybenzoic acid, resorcinol and chlorogenic acid each with concentration of 10^-4 M are done on the legume (Cajanus cajan (L.)Millsp.) AL-15. The effect of applied phenolic compounds as well as of structural differences in phenols indicate a marked influence of phenolic compounds in regulating growth processes in plants. Fresh and dry mass of various plant parts increased after foliar spray with phenols resulting in an improved harvest index. It is seen that phenols also play an important role in the initiation and development of nodules.     

Mevalonate-metabolizing enzymes in Arachis hypogaea

Summary The activities of the mevalonate metabolizing enzymes-HMG-CoA reductase, mevalonate kinase, mevalonate phosphokinase and mevalonate pyrophosphate decarboxylase -were assayed with the respective substrates in green seedlings of Arachis hypogaea. MVAPP decarboxylase is the rate-limiting step among these enzymes and is inhibited by phenolic acids. Its activity in the seedlings was found to decrease in the absence of light and on treatment with abscisic acid. These results suggest that regulation of isoprene pathway in groundnut seedlings may occur at the level of mevalonate decarboxylation.Abbreviations HMG CoA 3-hydroxy-3-methyl-glutaryl coenzyme A - MVA Mevalonate - MVAP Mevalonate-5-phosphate - MVAPP Mevalonate-5-pyrophosphate - DTT Dithiothreitol - ABA Abscisic Acid     

Molecular cytogenetic characterization of an alloplasmic durum wheat line with a portion of chromosome 1D of Triticum aestivum carrying the scs(ae) gene.

Triticum aestivum (2n = 6x = 42, AABBDD) with Triticum longissimum (2n = 2x = 14; S1S1) cytoplasm ((lo) cytoplasm) has normal fertility and plant vigor. However, the nucleus of durum wheat (Triticum turgidum (2n = 4x = 28, AABB)) is incompatible with the T. longissimum cytoplasm, producing non-viable progeny. This incompatibility is alleviated by scs(ae), a species cytoplasm-specific (scs) gene, on the long arm of chromosome 1D (1DL) of common wheat. The hemizygous (lo) durum scs(ae) line is male sterile and is maintained by crossing to normal durum wheat. After pollination, the seeds produced are either plump and viable (with scs(ae)) or shriveled and inviable (without scsae). Thus, the chromosome with scs(ae) is inherited as a whole without recombination. The objectives of this study were to characterize the chromosome carrying scs(ae) and to determine the process through which this gene was introgressed into the (lo) durum background. Molecular marker analysis with 27 probes and primers mapped to homoeologous group 1 and genomic in situ hybridization using differentially labeled total genomic DNA of durum wheat and Aegilops tauschii suggest the presence of a 1AL segment in place of the distal region of 1DL. Owing to the absence of any detectable duplications or deletions, homoeologous recombination is the most likely mechanism by which this introgression occurred.