Automated and simultaneous two-dimensional micro-high-performance liquid chromatographic determination of proline and hydroxyproline enantiomers in mammals

A fully automated 2D-HPLC system employing a microbore-ODS column and a narrowbore-enantioselective column has been developed for the simultaneous enantiomer determination of proline, trans-4-hydroxyproline and cis-4-hydroxyproline in mammals. As a first dimension, a monolithic ODS column of 0.53 mm i.d. showed 3-6 times larger theoretical plate numbers than those of particle-packed ODS columns, and the best enantioseparations were obtained by a Chiralpak QN-2-AX column of 1.5 mm i.d. in the second dimension (separation factors: 1.44-1.83). The R.S.D. values for within-day and dayto-day precisions were less than 5.8%, and the lower limits of quantitation for the D-enantiomers were 1 fmol. The present method was successfully applied to the determination of proline and hydroxyproline enantiomers in the serum and collagen-rich skin tissue. Small amounts of D-proline were found both in the serum (1.57 +/- 0.19 nmol/mL) and in the skin (0.093 +/- 0.015 nmol/mg protein), while the amounts of D-hydroxyproline were smaller than the lower limit of quantitation.     

Rapid and simple preparation of N-linked oligosaccharides by cellulose-column chromatography.

As a means of preparing N-linked oligosaccharides from hydrazinolysates of glycoproteins in a rapid and simple manner, a method has been developed using cellulose-column chromatography. Hydrazinolysates of human IgG, containing a series of biantennary complex type oligosaccharides, were applied to a cellulose column equilibrated with (4:1:1, v/v) 1-butanol-ethanol-water. The N-linked oligosaccharides were eluted with (1:1, v/v) ethanol-water, and analyzed by HPLC in combination with sequential glycosidase digestion. The oligosaccharides, with or without sialic acid, were quantitatively recovered in the fraction eluted with (1:1, v/v) ethanol-water without UV-detectable contamination by impurities derived from protein or the cellulose. Other types of N-linked oligosaccharides of alpha1-acid glycoprotein (tetraantennary complex-type), ovalbumin (hybrid-type), and ribonuclease B (high mannose-type) were also quantitatively prepared from the hydrazinolysates by elution of the cellulose column with (1:1, v/v) ethanol-water and these had as high a quality as those prepared by conventional paper chromatography.     

Abnormal IgG galactosylation and arthritis in MRL-Fas(lpr) or MRL-FasL(gld) mice are under the control of the MRL genetic background.

MRL mice bearing the lpr (Fas) or gld (Fas ligand) mutation, MRL-Fas(lpr) or MRL-FasL(gld), respectively, develop arthritis similar to rheumatoid arthritis, but C3H and C57BL/6 mice bearing such mutations do not. In MRL-Fas(lpr) mice, agalactosylated oligosaccharides in serum IgG increase significantly in comparison to MRL-+/+ mice without arthritis. In this study, an increased level of agalactosylation in IgG, as compared to MRL-+/+, was found in both MRL-Fas(lpr) and MRL-FasL(gld) mice. In contrast, the incidence of IgG without galactose was comparable among C3H-Fas(lpr), C3H-FasL(gld), and C3H-+/+ mice as well as between C57BL/6-Fas(lpr) and C57BL/6-+/+ mice. These results suggest that the increase in agalactosylated IgG and the development of arthritis in MRL-Fas(lpr) and MRL-FasL(gld) mice are controlled by the MRL genetic background.     

Prospectively Isolated Cancer-Associated CD10+ Fibroblasts Have Stronger Interactions with CD133+ Colon Cancer Cells than with CD133? Cancer Cells

Although CD133 has been reported to be a promising colon cancer stem cell marker, the biological functions of CD133⁺ colon cancer cells remain controversial. In the present study, we investigated the biological differences between CD133⁺ and CD133⁻ colon cancer cells, with a particular focus on their interactions with cancer-associated fibroblasts, especially CD10⁺ fibroblasts. We used 19 primary colon cancer tissues, 30 primary cultures of fibroblasts derived from colon cancer tissues and 6 colon cancer cell lines. We isolated CD133⁺ and CD133⁻ subpopulations from the colon cancer tissues and cultured cells. In vitro analyses revealed that the two populations showed similar biological behaviors in their proliferation and chemosensitivity. In vivo analyses revealed that CD133⁺ cells showed significantly greater tumor growth than CD133⁻ cells (P = 0.007). Moreover, in cocultures with primary fibroblasts derived from colon cancer tissues, CD133⁺ cells exhibited significantly more invasive behaviors than CD133⁻ cells (P<0.001), especially in cocultures with CD10⁺ fibroblasts (P<0.0001). Further in vivo analyses revealed that CD10⁺ fibroblasts enhanced the tumor growth of CD133⁺ cells significantly more than CD10⁻ fibroblasts (P<0.05). These data demonstrate that the in vitro invasive properties and in vivo tumor growth of CD133⁺ colon cancer cells are enhanced in the presence of specific cancer-associated fibroblasts, CD10⁺ fibroblasts, suggesting that the interactions between these specific cell populations have important roles in cancer progression. Therefore, these specific interactions may be promising targets for new colon cancer therapies.     

Skill-Specific Changes in Somatosensory Nogo Potentials in Baseball Players

Athletic training is known to induce neuroplastic alterations in specific somatosensory circuits, which are reflected by changes in somatosensory evoked potentials and event-related potentials. The aim of this study was to clarify whether specific athletic training also affects somatosensory Nogo potentials related to the inhibition of movements. The Nogo potentials were recorded at nine cortical electrode positions (Fz, Cz, Pz, F3, F4, C3, C4, P3 and P4) in 12 baseball players (baseball group) and in 12 athletes in sports, such as track and field events and swimming, that do not require response inhibition, such as batting for training or performance (sports group). The Nogo potentials and Go/Nogo reaction times (Go/Nogo RTs) were measured under a somatosensory Go/Nogo paradigm in which subjects were instructed to rapidly push a button in response to stimulus presentation. The Nogo potentials were obtained by subtracting the Go trial from the Nogo trial. The peak Nogo-N2 was significantly shorter in the baseball group than that in the sports group. In addition, the amplitude of Nogo-N2 in the frontal area was significantly larger in the baseball group than that in the sports group. There was a significant positive correlation between the latency of Nogo-N2 and Go/Nogo RT. Moreover, there were significant correlations between the Go/Nogo RT and both the amplitude of Nogo-N2 and Nogo-P3 (i.e., amplitude of the Nogo-potentials increases with shorter RT). Specific athletic training regimens may induce neuroplastic alterations in sensorimotor inhibitory processes.     

Escherichia coli mutants deficient in the production of alkaline phosphatase isozymes.

Escherichia coli K-12 mutants showing an altered isozyme pattern of alkaline phosphatase were isolated. Whereas wild-type strains synthesized all three isozymes in a synthetic medium supplemented with Casamino Acids or arginine but synthesized only isozyme 3 in a medium without supplement, the mutant strains synthesized isozyme 1 and a small amount (if any) of isozyme 2, but no isozyme 3, under all growth conditions. The mutation responsible for the altered isozyme pattern, designated iap, was mapped by P1 transduction in the interval between cysC and srl (at about 58.5 min on the E. coli genetic map). It was cotransducible with cysC and srl at frequencies of 0.54 and 0.08, respectively. The order of the genes in this region was srl-iap-cysC-argA-thyA-lysA. Three more independent mutations were also mapped in the same locus. We purified isozymes 1' and 3' from iap and iap+ strains and analyzed the sequences of four amino acids from the amino terminus of each polypeptide. They were Arg-Thr-Pro-Glu (or Gln) in isozyme 1' and Thr-Pro-Glu (or gln)-Met in isozyme 3', which were identical with those of corresponding isozymes produced by the wild-type phoA+ strain (P.M. Kelley, P.A. Neumann, K. Schriefer, F. Cancedda, M.J. Schlesinger, and R.A. Bradshaw, Biochemistry 12:3499-3503, 1973; M.J. Schlesinger, W. Bloch, and P.M. Kelley, p. 333-342, in Isozymes, Academic Press Inc., 1975). These results indicate that the different mobilities of isozymes 1, 2, and 3 are determined by the presence or absence of amino-terminal arginine residues in polypeptides.     

Changes in Brain Tissue and Behavior Patterns Induced by Single Short-Term Fasting in Mice

In humans, emaciation from long-term dietary deficiencies, such as anorexia, reportedly increases physical activity and brain atrophy. However, the effects of single short-term fasting on brain tissue or behavioral activity patterns remain unclear. To clarify the impact of malnutrition on brain function, we conducted a single short-term fasting study as an anorexia model using male adult mice and determined if changes occurred in migratory behavior as an expression of brain function and in brain tissue structure. Sixteen-week-old C57BL/6J male mice were divided into either the fasted group or the control group. Experiments were conducted in a fixed indoor environment. We examined the effects of fasting on the number of nerve cells, structural changes in the myelin and axon density, and brain atrophy. For behavior observation, the amount of food and water consumed, ingestion time, and the pattern of movement were measured using a time-recording system. The fasted mice showed a significant increase in physical activity and their rhythm of movement was disturbed. Since the brain was in an abnormal state after fasting, mice that were normally active during the night became active regardless of day or night and performed strenuous exercise at a high frequency. The brain weight did not change by a fast, and brain atrophy was not observed. Although no textural change was apparent by fasting, the neuronal neogenesis in the subventricular zone and hippocampus was inhibited, causing disorder of the brain function. A clear association between the suppression of encephalic neuropoiesis and overactivity was not established. However, it is interesting that the results of this study suggest that single short-term fasting has an effect on encephalic neuropoiesis.