In vitro screening procedure for osmotic tolerance in Prunus

Significant growth differences (p<0.01) were observed for two micropropagated Prunus accessions after 14 days in culture when 685 mM mannitol was included in Quoirin and Lepoivre nutrient medium. While there was an 11% growth increase in fresh weight during the 28-day culture period for accession K537-067, explants from New Jersey Plumcot No. 3 increased fresh weight an average of 123%. Similar tests were conducted to determine the repeatability of this short term in vitro screening procedure. Explants of Mananna 2624 were subjected to two levels of mannitol, 275 mM and 550 mM, included in the Quoirin and Lepoivre nutrient medium. Three successive 28-day tests were conducted. Explants were examined at both 14 and 28 days after the onset of the experiment for net growth changes. Addition of mannitol to the nutrient medium at concentrations of 275 mM and 550 mM decreased explant fresh weights of Marianna 2624 to 36% and 28% of controls, respectively, at 28 days past initial culture. Initial fresh weight and fresh weight changes at day 14 were significantly different (p 0.05) between tests. No significant differences existed between tests with regard to weight changes at 28 days past initial culture. This information may aid Prunus breeders in the choice of procedures for inducing drought stress and screening large numbers of plant accessions.Abbreviations K5 K537-067 - M2624 Marianna 2624 - NJPC3 New Jersey Plumcot No. 3 - Q & L Quoirin and Lepoivre     

An expeditious synthesis of blood-group antigens,ABO histo-blood group type II antigens and xenoantigen oligosaccharides with amino type spacer−arms

Blood group oligosaccharides are one of the most clinically important antigen families and they may also act as secondary ligands for bacterial toxins from Escherichia coli and Vibrio cholerae. Herein we report the synthesis of spacered (sp = CH₂CH₂CH₂NH₂) glycosides of A antigen {α-D-GalNAc-(l→3)-[α-L-Fuc-(l→2)]-β-D-Gal-}, B antigen{α-D-Gal-(l→3)-[α-L-Fuc-(l→2)]-β-D-Gal-}, LewisX{α-D-Gal-(l→4)-[α-L-Fuc-(l→3)]-β-D-GlcNAc-}, A type-II {α-D-GalNAc-(l→3)-[α-L-Fuc-(l→2)]-β-D-Gal-(1→4)-β-D-GlcNAc-}, B type-II {α-D-Gal-(l→3)-[α-L-Fuc-(l→2)]-β-D-Gal-(1→4)-β-D-GlcNAc-}, H type-II{α-L-Fuc-(l→2)-β-D-Gal-(1→4)-β-D-GlcNAc-}, xenoantigen {α-D-Gal-(l→3)-β-D-Gal-(1→4)-[α-L-Fuc-(l→2)]-β-D-GlcNAc-} and Linear B Type II {α-D-Gal-(l→3)-β-D-Gal-(1→4)-β-D-GlcNAc-} useful for a range of biochemical investigations. This linker was chosen so as to facilitate the future conjugation of the antigens to proteins or other molecules. We also measured the affinities of some synthesized oligosaccharides against El Tor CTB strain from V. cholera.     

Cytotoxicity of zinc chloride in mice in vivo

Intraperitoneal administration of zinc chloride (ZnCl2) to Swiss albino mice in vivo induced a significant (p less than or equal to 0.05) increase in the frequencies of chromosomal aberrations of the bone-marrow cells at all concentrations used following acute (7.5, 10, 15 mg/kg body weight) and chronic (2.0, 3.0 mg/kg body wt) treatment. The degree of clastogenicity was directly proportional to the concentrations (p less than or equal to 0.05, trend test) and indirectly to the period of treatment (p less than or equal to 0.05, ANOVA test). It induced a dose-dependent, statistically significant increase (Mann-Whitney U statistics, Student's t-test) in sperm-head abnormalities. The data designate ZnCl2 as a potent clastogen and as a toxic chemical at the concentrations used.     

Interaction of nematodes with nematophagus fungi: induction of trap formation, attraction and detection of attractants

Induction of trap formation in Arthrobotrys oligospora, A. conoides and Monacrosporium cystosporum was studied during a 24 h period in the presence of the free-living nematodes Panagrellus redivivus on various nutrient media. A definite pattern of trap formation was observed in these fungi. Low nutrient mineral salt medium had the most pronounced effect on trap formation. Attraction and repulsion of P. redivivus towards these three nematophagous and three non-nematophagous fungi was studied. The nematodes were attracted towards three nematophagous and one non-nematophagous fungi, the other two repelled them. Attractants of the nematophagous fungi were determined by thin-layer chromatography. In the case of A. oligospora and M. cystosporum, four spots were traced, whereas in A. conoides, five spots were detected.     

Murine nasal septa for respiratory epithelial air-liquid interface cultures

Air-liquid interface models using murine tracheal respiratory epithelium have revolutionized the in vitro study of pulmonary diseases. This model is often impractical because of the small number of respiratory epithelial cells that can be isolated from the mouse trachea. We describe a simple technique to harvest the murine nasal septum and grow the epithelial cells in an air-liquid interface. The degree of ciliation of mouse trachea, nasal septum, and their respective cultured epithelium at an air-liquid interface were compared by scanning electron microscopy (SEM). Immunocytochemistry for type IV beta-tubulin and zona occludens-1 (Zo-1) are performed to determine differentiation and confluence, respectively. To rule out contamination with olfactory epithelium (OE), immunocytochemistry for olfactory marker protein (OMP) was performed. Transepithelial resistance and potential measurements were determined using a modified vertical Ussing chamber SEM reveals approximately 90% ciliated respiratory epithelium in the nasal septum as compared with 35% in the mouse trachea. The septal air-liquid interface culture demonstrates comparable ciliated respiratory epithelium to the nasal septum. Immunocytochemistry demonstrates an intact monolayer and diffuse differentiated ciliated epithelium. These cultures exhibit a transepithelial resistance and potential confirming a confluent monolayer with electrically active airway epitheliumn containing both a sodium-absorptive pathway and a chloride-secretory pathway. To increase the yield of respiratory epithelial cells harvested from mice, we have found the nasal septum is a superior source when compared with the trachea. The nasal septum increases the yield of respiratory epithelial cells up to 8-fold.