Diurnal rhythms of proopiomelanocortin-derived N-terminal peptide, beta-lipotropin, beta-endorphin and adrenocorticotropin in normal subjects and in patients with Addison's disease and Cushing's disease

In order to clarify the diurnal pattern of secretion of plasma immunoreactive (IR) proopiomelanocortin (POMC)-derived peptides, IR-N-terminal peptide (Nt), IR-beta-endorphin (Ep), IR-beta-lipotropin (LPH), and IR-ACTH (ACTH) in normal subjects and in patients with Addison's disease and Cushing's disease, we measured these 4 peptides in the same plasma obtained at 0900 h and then every three hours until 0600 h at the next day. All four peptides showed diurnal rhythms with the peaks at 0600 h, and the nadirs of ACTH, LPH, Ep and Nt were at 0000 h, 0000 h, 1800 h and 0300, respectively in normal subjects. In patients with Addison's disease, these four peptides also showed diurnal rhythms with the peaks at 0600 h for ACTH and Ep and at 0900 h for LPH and Nt, and the nadirs at 2100 h for ACTH and Ep and at 0000 h for LPH and Nt. The molar ratios of Ep/ACTH, LPH/ACTH and Nt/ACTH in plasma also presented diurnal variations in normal subjects and in patients with Addison's disease. On the other hand, in patients with Cushing's disease, ACTH, LPH and Nt showed no rhythmicity or change in molar ratios of Ep/ACTH, LPH/ACTH or Nt/ACTH. Only Ep showed diurnal variation. The molar ratios of Ep/ACTH, LPH/ACTH and Nt/ACTH in patients with Cushing's disease were significantly higher than those in normal subjects and in patients with Addison's disease at 0000 h.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immunological detection of propolypeptide of von Willebrand factor on platelet surface

Recently we have found that propolypeptide of von Willebrand factor (pp-vWF) obtained from platelets binds to type I collagen. It is known that pp-vWF is present in platelet alpha-granules and is secreted upon activation. In this paper, we demonstrate the two following evidences to show that it is also present on the surface of resting platelets. [1] The antibody against pp-vWF bound to the surface of platelets. [2] The antibody induced aggregation of platelets. The binding of the antibody and the antibody-induced aggregation of platelets were inhibited in a dose-dependent manner by Fab fragment of the antibody. Platelets from von Willebrand disease patients bound less of the antibody and responded weakly to the antibody.     

Effect of phosphatidylinositol replacement by diacylglycerol on various physical properties of artificial membranes with respect to the role of phosphatidylinositol response

In an attempt to gain insight into the physiological role of phosphatidylinositol turnover enhanced by extracellular stimuli, the physical properties of artificial membranes (egg yolk phosphatidylcholine/bovine brain phosphatidylserine) containing phosphatidylinositol or diacylglycerol were studied by ESR using spin probes and freeze-fracture electron microscopy. Diacylglycerol lost both the ability to form lipid bilayer structures and its susceptibility to calcium ions. Yeast phosphatidylinositol included in dipalmitoylphosphatidylcholine liposomes lowered the phase transition temperature of dipalmitoylphosphatidylcholine and expanded the temperature range of phase transition. However, diacylglycerol at the same concentration did not undergo the effects caused by phosphatidylinositol but the phase transition temperature was slightly raised. Phase separation of phosphatidylserine induced by calcium ions was enhanced when the phosphatidylinositol was replaced by diacylglycerol in phosphatidylcholine/ phosphatidylserine/phosphatidylinositol (3:5:2, by molar ratio) mixtures. The mobility of phosphatidylcholine spin probe was decreased in phosphatidylcholine/ phosphatidylserine/diacylglycerol (3:5:2, by molar ratio) liposomes compared with phosphatidylcholine/phosphatidylserine/phosphatidylinositol (3:5:2, by molar ratio) liposomes. An additional component from protonated stearic acid spin probes was observed in phosphatidylcholine/phosphatidylinositol (8:2, by molar ratio) liposomes at 40°C, whereas the component was not seen in phosphatidylcholine/diacylglycerol (8:2, by molar ratio) liposomes. This may indicate the alteration of surface charge induced by the replacement of phosphatidylinositol by diacylglycerol. Indeed, in the presence of 1 mM Ca²⁺, the additional component was removed by an electrostatic interaction between Ca²⁺ and phosphatidylinositol molecules in phosphatidylcholine/phosphatidylinositol liposomes at 40°C. These results support the hypothesis that the enhanced turnover of phosphatidylinositol may play a triggering role for various cellular responses to exogenous stimuli by altering membrane physical states.     

Physiological studies on the action of CCC in Kyoho grapes

The physiological action of CCC for leaves of Kyoho grapes wasstudied. Leaves from the lower to upper positions of the primaryshoots and (primary) lateral shoots showed uneven photosyntheticactivities with peaks. The photosynthetic activity of each leaffrom both shoots was increased by treatment with CCC, whereasrespiratory activity was not affected with CCC. In the primaryshoots, CCC treatment increased the contents of chlorophylla and b in the leaves, but in the lateral shoots only chlorophyllb contents were increased. Dry weights of the leaves from thelateral shoots increased with CCC, but those of leaves locatedin the vicinity of nodes bearing the fruit clusters varied slightlyor were almost the same as the dry weight of non-treated leaves.Leaf thickness was increased by CCC and paralleled the variationin dry weight. The leaf area was decreased by CCC. (Received April 19, 1980; )     

14-Fluorobacteriorhodopsin and other fluorinated and 14-substituted analogues. An extra, unusually red-shifted pigment formed during dark adaptation

Five vinyl-substituted fluororetinal analogues (8-F, 10-F, 12-F, 14-F, and 13,14-F2) were found to give bacteriorhodopsin analogues with properties similar to those of the parent system. Of these, only 14-fluororetinal was found to give an extra red-shifted BR analogue (lambda max less than or equal to 680 nm) in equilibrium with the normal 587-nm pigment. The 680-nm pigment was enriched upon irradiation. It rearranged to the 587-nm pigment at room temperature (delta E [symbol: see text] = 20.8 kcal/mol). Chromophore extraction experiments revealed the all-trans geometry for the 680-nm pigment. 14-Chlororetinal gave a similarly red-shifted pigment while 14-methylretinal did not. A scheme for dark adaptation of the 14-halogenated bacteriorhodopsins has been proposed in which the new red-shifted pigment was assigned the all-trans, 15-syn geometry.     

An oral Salmonella vaccine promotes the down-regulation of cell surface Toll-like receptor 4 (TLR4) and TLR2 expression in mice

A single oral immunization with the Lon-protease-deficient Salmonella enterica serovar Typhimurium (strain CS2022) induced protective immunity in mice against a subcutaneous challenge with virulent Listeria monocytogenes as well as virulent Salmonella serovar Typhimurium. The populations of cell surface Toll-like receptor 4 (TLR4) and TLR2 on peritoneal macrophages decreased at week 6 after immunization. This population decrease was not reversed after a challenge with either Salmonella or Listeria. These results suggest that oral immunization with CS2022 induced immune tolerance correlated with the down-regulation of cell surface TLR expression. This down-regulation may in part account for the development of cross-protection against a Listeria challenge by immunization with CS2022.     

Association of a regulatory gene, slyA with a mouse virulence of Salmonella serovar Choleraesuis

The influence of slyA gene, originally found in Salmonella serovar Typhimurium as a regulatory gene for the expression of virulence genes, on a mouse virulence of S. serovar Choleraesuis was investigated by using an slyA-defective mutant. The defective mutant was constructed by the insertion of a kanamycin-resistance gene (aph) into the cloned slyA gene, and the homologous recombination with the intact slyA gene on the chromosome. The mutant strain showed the LD50 value for BALB/c mouse approximately 10(5) higher than that of the parent strain. The increase of the LD50 value was the same order as that shown by the mutation of the slyA gene of S. serovar Typhimurium, although LD50 of the wild-type strain of S. serovar Choleraesuis was 40-fold higher than that of S. serovar Typhimurium. The time course of infection observed in the mice organs also proved the clear difference of the virulence between the parent and the mutant strains. These results suggested that the slyA gene product functions as a virulence-associated regulator also in S. serovar Choleraesuis.     

Characterization of hypervariable regions in the putative envelope protein of hepatitis C virus.

We previously identified two hypervariable regions [HVR1 (27 amino acids) and HVR2 (7 amino acids)] in the putative envelope glycoprotein (gp70) by comparison of the amino acid sequences of many isolates of the HCV-II genotype. To understand the functional features of these HVRs, using the polymerase chain reaction we analyzed the rate of actual sequence variability in the region including HVR1 and HVR2 of HCV isolated successively at intervals of several months from two patients with chronic C-type hepatitis. In both patients, the amino acid sequence of HVR1, but not HVR2, was found to change dramatically during the observation period (about one amino acid per month). However, no alteration of the amino acid sequence of HVR1 of HCV was observed in a patient in the acute phase of chronic hepatitis. Restriction digestion analysis of sequence diversity showed that a HCV genome with a newly introduced mutation in HVR1 often became the predominant population at the next time of examination. Alterations of amino acids in HVR1 occurred sequentially in the two patients in the chronic phase. These findings suggest that mutations in HVR1 are involved in the mechanism of persistent chronic HCV infection.     

Serine protease inhibitors modulate chemotactic cytokine production by human lung fibroblasts in vitro

Chemotactic chemokines can be released from lung fibroblasts in response to interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha. An imbalance between proteases and antiproteases has been observed at inflammatory sites, and, therefore, protease inhibitors might modulate fibroblast release of chemotactic cytokines. To test this hypothesis, serine protease inhibitors (FK-706, alpha(1)-antitrypsin, or N(alpha)-p-tosyl-L-lysine chloromethyl ketone) were evaluated for their capacity to attenuate the release of neutrophil chemotactic activity (NCA) or monocyte chemotactic activity (MCA) from human fetal lung fibroblasts (HFL-1). Similarly, the release of the chemoattractants IL-8, granulocyte colony-stimulating factor, monocyte chemoattractant protein-1, macrophage colony-stimulating factor, and granulocyte/macrophage colony-stimulating factor, from HFL-1, were evaluated in response to IL-1beta and TNF-alpha. NCA, MCA, and chemotactic cytokines were attenuated by FK-706. However, matrix metalloproteinase inhibitors were without effect, and cysteine protease inhibitors only slightly attenuated chemotactic or cytokine release. These data suggest that IL-1beta and TNF-alpha may stimulate lung fibroblasts to release NCA and MCA by a protease-dependent mechanism and that serine protease inhibitors may attenuate the release.