Storage of human bone marrow before transplantation at 4 degrees C. The effect of cell proliferation potential particularly in hematopoietic cloned cell lines

The possibility of storage of human bone marrow CD34+ cells at 4 degrees C for bone marrow transplantation purposes was investigated. The cells were placed in Iscove medium supplemented with 20% serum (15% bovine calf serum + 5% human AB serum) for three weeks at 4 degrees C. During storage time clonogenicity of granulocytic-monocytic (CFU-GM) erythropoietic (BFU-E) and megakaryocytic (CFU-Meg) progenitors were investigated. It turns out that it is possible to keep human CD34+ cells at 4 degrees C for at least few days before transplantation. At day four of storage the number of CFU-GM and BFU-E cells still exceeded 50% of cells present at day 0. We have found however, CFU-Meg progenitors in comparison to others are much more sensitive to metabolic storage stress. This enhanced sensitivity of megakaryocytic progenitors could explain at least partially the well known ++phenomenon of retardation of thrombopoietic recovery in patients undergoing bone marrow transplantation.     

Haemoglobin binding with haptoglobin. Unequivocal demonstration that the beta-chains of human haemoglobin bind to haptoglobin

Haptoglobin binding to haemoglobin and its isolated alpha- and beta-chains was studied by use of a highly sensitive solid-phase radiometric assay. As expected, adsorbents of haemoglobin bound 125I-labelled haptoglobin more efficiently than did adsorbents of the alpha-chain. However, unexpectedly, adsorbents of the beta-chain were found to be essentially identical with those of the alpha-chain in their ability to bind haptoglobin. These results demonstrate, unequivocally, the ability of beta-chains to bind to haptoglobin, and indicate that this assay is particularly convenient and useful for studying haptoglobin interactions with haemoglobin and its alpha- and beta-chains.     

A comparative analysis of juvenile hormone metabolyzing enzymes in two species of Drosophila during development

The course of changes in the activities of enzymes degrading juvenile hormone (JH), epoxyde hydrolase (JHEH) and JH-esterase (JHE) was studied in two lines of Drosophila virilis (101 and 147) and in two lines of D. melanogaster (Canton-S and 921283). It was established for D. virilis that changes in the JH titre during pupal-adult development is determined by the activity level of JHE rather then JHEH, while in D. melanogaster developmental changes in JH titre are related to changes in the activity level of both JHE and JHEH. In adults of D. virilis, the high level of JH-hydrolysing activity is determined by JHE and in those of D. melanogaster by JHEH. Differences in the course of changes in the JHE activity level between adults of lines 101 and 147 of D. virilis were found, and also in the JHEH activity level between adults of lines Canton S and 921283 of D. melanogaster. It was shown that attainment of a definite JHE activity level in females of lines 101 and 147 agrees well with the onset of oviposition of fertilized eggs. The possible role of JHE in reproduction of D. virilis is discussed.     

The standard of care for oral diagnosis as it relates to oral cancer

The periodic oral examination of patients must be performed by the dentist as standard procedure. As a physician of the mouth, the dentist must also be able to recognize abnormalities or lesions and then provide, or refer patients for, diagnosis, treatment, and surveillance of the condition. With prompt and decisive action, the dentist can save lives and influence the morbidity of oral cancer. Conversely, inadequate diagnostic skills and improper documentation techniques can incur legal consequences.     

Polysulfated carbohydrates analyzed as ion-paired complexes with basic peptides and proteins using electrospray negative ionization mass spectrometry

Electrospray ionization mass spectrometry was used in the negative ion mode to analyze complexes of sucrose octasulfate, sucrose heptasulfate and sulfated alpha-, beta- and gamma-cyclodextrins with synthetically prepared basic peptides, the basic protein ubiquitin and polyamines. The spectra presented demonstrate that complexes with these basic molecules facilitate the analysis of these polysulfated oligosaccharides. Stable (1:1) complexes result from the ion pairing between the protonated basic arginine and lysine residues of the peptide and the anionic sulfate groups of the polysulfated oligosaccharides. Fragmentation of the polysulfated oligosaccharides resulting in the loss of SO3 could be suppressed by controlling the experimental conditions, such as the nozzle-skimmer voltage, used to obtain the spectra. In the absence of fragmentation, it was possible to obtain data on the purity of sucrose octasulfate and sucrose heptasulfate as well as the distribution of the sulfated cyclodextrins. The confounding presence of sodium counter-ions is also eliminated using this method. Complete chemical sulfation of oligosaccharides is difficult to achieve. Thus, data on sample purity are essential for the characterization of sulfated oligosaccharides used as pharmaceutical agents.