Long-term blood pressure variability and cerebrovascular changes on CT in a community-based elderly population

The effects of long-term blood pressure (BP) levels on cerebrovascular changes were analyzed in a community-based healthy elderly population. Cranial computed tomography (CT) was performed for 300 residents aged 69 years and older. Long-term BP during the ten years prior to CT was assessed, and the cerebrovascular changes were compared among different patterns of long-term blood pressure variability. White matter lesions (WML) and/or silent infarctions (SI) were found in 73 subjects (23.6%). Multiple logistic regression analysis showed that subjects with long-term diastolic hypertension (DHT) had the highest risk of cerebrovascular changes (adjusted odds ratio (OR), 95% confidence interval (CI); 7.1, 2.4-21.6, for WML; 7.2, 2.7-19.4, for SI), and that long-term isolated systolic hypertension (ISHT) was significantly associated with SI (adjusted OR, 95%CI, 2.3, 1.1-4.9), but not with WML (adjusted OR, 95%CI, 1.3, 0.5-3.3). Efforts to prevent both DHT and ISHT would be beneficial, though different underlying mechanisms for WML and SI were suggested.

Synovial inflammation and hyperplasia induced by gliostatin/platelet-derived endothelial cell growth factor in rabbit knees

Neovascularization, proliferation of synovial cells, and mononuclear cell influx and activation are characteristic events observed in synovial joints in the pathohistology of rheumatoid arthritis (RA). The objective of this study was to examine synovial inflammation in rabbit knees induced by intra-articular administration of human gliostatin/platelet-derived endothelial cell growth factor (GLS/PD-ECGF), which shares a high degree of chemical homology with thymidine phosphorylase (dThdPase) and is known to have angiogenic activity. Purified recombinant human gliostatin (rHuGLS) and its mutant protein, which was prepared by site-directed mutagenesis and which lacks dThdPase activity, were administered at various doses to rabbit knee joints. The effects of rHuGLS and the mutant were examined histologically. Intra-articular injection of rHuGLS resulted in the development of diffuse synovitis resembling RA. The mutant protein also brought about the same effect. These findings suggest that human GLS can cause RA-like synovitis in rabbit knee joints via a mechanism other than its dThdPase activity.

Postnatal development of synovial capillaries of rats with special reference to permeability

The size of a substance is a major factor determining whether it can permeate the wall of synovial capillaries. The maximum diameter of particles that can move across the synovial capillary wall has generally been thought to be 50 nm. We studied the permeability of the synovial capillaries of the rat between day 20 and 30 after birth using a polystyrene particle whose diameter was 240 nm. In addition using lecithin-coated polystyrene particles, we studied the maturation of the barrier function supported by endothelial and peripheral cells against foreign bodies. Lecithin-coated particles were found within the fibroblast-like synovial cells near the capillary in the 20 day-old rats, while non-coated particles remained in the endothelial wall and in the peripheral cells of capillaries. In the 30 day-old rats, lecithin-coated particles were present in the peripheral cells and the neighboring synovial cells; however, the non-coated particles were never found in the synovial or perisynovial cells. The present study shows that the size of the transportable substance by transcytosis may be larger than previously thought. Furthermore, the synovial capillaries functionally changed between day 20 and 30 suggesting that active movement of the joint led to the functional maturation of the synovial capillaries.

A Drosophila Winged-helix nude (Whn)-like transcription factor with essential functions throughout development

A Drosophila gene, Dwhn (Drosophila whn-like), encoding a putative transcriptional regulator with a DNA binding domain similar to that of mouse Winged-helix nude (Whn) was cloned. Analyses of the phenotypes produced by a hypomorphic mutation and transgene expression suggested a role in cell fate decision during the differentiation of the compound eye, wing veins and bristles. During embryonic development, Dwhn expression started ubiquitously followed by more restricted expression in striking contrast to the expression patterns of other Drosophila forkhead (fkh) family genes whose local expression correlate well to their roles as local homeotic genes. This broad expression may correspond to the multiple defects in embryos homozygous for strong alleles, such as defects in the formation of central and peripheral nervous systems, germ band retraction, head involution, and dorsal closure. The DNA binding specificity of Dwhn differed from that of Whn despite the strong sequence conservation in the DNA binding domain. Dwhn is the first invertebrate Whn-like transcriptional regulator, and should provide insights into the basic functions and evolution of the whn family genes.

In Situ Polymerase Chain Reaction Visualization of Vibrio halioticoli Using Alginate Lyase Gene AlyVG2

A prokaryotic in situ polymerase chain reaction (PI-PCR) technique was applied to visualize Vibrio halioticoli cells using alginate lyase gene alyVG2 as a target gene. Prior to PI-PCR, a primer set, VG2-OS3, for specific amplification of an approximately 1.0-kb fragment from V. halioticoli genomic DNA was developed with amplified fragments from V. pelagius and V. fischeri DNAs as reference strains. One-stage PI-PCR using the primer set, digoxigenin-labeled dUTP, and indirect alkaline-phosphatase-linked fluorescence detection technique (HNPP/Fast Red TR as a substrate) failed to differentiate V. halioticoli IAM14596(T) cells from ATCC25916(T) cells of the closely related species V. pelagius. However, two-stage PI-PCR adding the extension and digoxigenin-labeling step of the amplified fragment into the first amplification stage allowed us to differentiate V. halioticoli cells from V. pelagius cells.

Cloning and Sequence Analysis of Vibrio halioticoli Genes Encoding Three Types of Polyguluronate Lyase

The alginate lyase-coding genes of Vibrio halioticoli IAM 14596(T), which was isolated from the gut of the abalone Haliotis discus hannai, were cloned using plasmid vector pUC 18, and expressed in Escherichia coli. Three alginate lyase-positive clones, pVHB, pVHC, and pVHE, were obtained, and all clones expressed the enzyme activity specific for polyguluronate. Three genes, alyVG1, alyVG2, and alyVG3, encoding polyguluronate lyase were sequenced: alyVG1 from pVHB was composed of a 1056-bp open reading frame (ORF) encoding 352 amino acid residues; alyVG2 gene from pVHC was composed of a 993-bp ORF encoding 331 amino acid residues; and alyVG3 gene from pVHE was composed of a 705-bp ORF encoding 235 amino acid residues. Comparison of nucleotide and deduced amino acid sequences among AlyVG1, AlyVG2, and AlyVG3 revealed low homologies. The identity value between AlyVG1 and AlyVG2 was 18.7%, and that between AlyVG2 and AlyVG3 was 17.0%. A higher identity value (26.0%) was observed between AlyVG1 and AlyVG3. Sequence comparison among known polyguluronate lyases including AlyVG1, AlyVG2, and AlyVG3 also did not reveal an identical region in these sequences. However, AlyVG1 showed the highest identity value (36.2%) and the highest similarity (73.3%) to AlyA from Klebsiella pneumoniae. A consensus region comprising nine amino acid (YFKAGXYXQ) in the carboxy-terminal region previously reported by Mallisard and colleagues was observed only in AlyVG1 and AlyVG2.

A possible barrier function of the articular surface

Since MacConaill first reported the existence of a thin additional layer of the articular cartilage and named it the lamina splendens, there have been various opinions as to the role of this layer in the lubrication of the articular surface. We studied the superficial portion of the articular cartilage in the 20 day-old and 30 day-old rats using light and transmission electron microscopy. Furthermore, we studied the articular cartilage of the rat whose "cover layer" had been removed mechanically. Also, intraarticular latex beads injection, intraarticular dye injection using lithium carmine and supravital staining experiments were performed. On day 20, dye injected intraarticularly was clearly observed by light microscopy in chondrocytes situated in the deeper layers. The dye injected in the 30 day-old rats, however, was not seen in the chondrocytes but was found only in the superficial layer. Dye was found in the chondrocytes when supravital staining was performed in the articular cartilage of 30 day-old rats after mechanical removal of the cover layer. By transmission electron microscopy, a superficial layer consisted of fine filamentous structures was observed on the articular surface of the 30 day-old rats. The cover layer was destroyed by intraarticular injected latex beads in 30 day-old rats. These findings strongly support the idea that the cover layer acts as a barrier against substances which invade from the surface of the articular cartilage. The development period of the cover layer coincides with the initiation of weight bearing, and joint cartilage debris and pressure changes might further promote maturation.

De novo synthesis of sphingolipids is required for cell survival by down-regulating c-Jun N-terminal kinase in Drosophila imaginal discs

Mitogen-activated protein kinase (MAPK) is a conserved eukaryotic signaling factor that mediates various signals, cumulating in the activation of transcription factors. Extracellular signal-regulated kinase (ERK), a MAPK, is activated through phosphorylation by the kinase MAPK/ERK kinase (MEK). To elucidate the extent of the involvement of ERK in various aspects of animal development, we searched for a Drosophila mutant which responds to elevated MEK activity and herein identified a lace mutant. Mutants with mild lace alleles grow to become adults with multiple aberrant morphologies in the appendages, compound eye, and bristles. These aberrations were suppressed by elevated MEK activity. Structural and transgenic analyses of the lace cDNA have revealed that the lace gene product is a membrane protein similar to the yeast protein LCB2, a subunit of serine palmitoyltransferase (SPT), which catalyzes the first step of sphingolipid biosynthesis. In fact, SPT activity in the fly expressing epitope-tagged Lace was absorbed by epitope-specific antibody. The number of dead cells in various imaginal discs of a lace hypomorph was considerably increased, thereby ectopically activating c-Jun N-terminal kinase (JNK), another MAPK. These results account for the adult phenotypes of the lace mutant and suppression of the phenotypes by elevated MEK activity: we hypothesize that mutation of lace causes decreased de novo synthesis of sphingolipid metabolites, some of which are signaling molecules, and one or more of these changes activates JNK to elicit apoptosis. The ERK pathway may be antagonistic to the JNK pathway in the control of cell survival.

Vibrio halioticoli sp. nov., a non-motile alginolytic marine bacterium isolated from the gut of the abalone Haliotis discus hannai

Six alginolytic, facultatively anaerobic, non-motile marine bacteria were isolated from the gut of abalone Haliotis discus hannai. DNA-DNA hybridization data showed that the six strains constituted a single genospecies. Phylogenetic analyses of 16S rDNA sequences indicated that the isolates should be assigned to the genus Vibrio. The phenotypic features of the isolates were closely related to Vibrio fischeri and Vibrio pelagius biovar I, but 13 traits (motility, luminescence, alginase production, lipase production, lysine decarboxylase, indole production, growth in 1 and 6% NaCl and assimilation of five carbon compounds) distinguished these strains from V. fischeri, and 17 traits (motility, growth at 37 degrees C, lipase production, indole production, growth in 1 and 6% NaCl, acid from sucrose and D-sorbitol, and assimilation of nine carbon compounds) distinguished these strains from V. pelagius. The G + C content of the isolates was 41.6-43.1 mol%. According to DNA-DNA hybridization data and 16S rDNA phylogenetic analyses, it was concluded that the six isolates constitute a new species different from any other Vibrio species. The name Vibrio halioticoli sp. nov. (type strain IAM 14596T) is proposed. A set of phenotypic features which enables differentiation of the new species from other species of the Vibrionaceae family is described.

Gliostatin/platelet-derived endothelial cell growth factor as a clinical marker of rheumatoid arthritis and its regulation in fibroblast-like synoviocytes

The objective was to assess the congruity of gliostatin/platelet-derived endothelial cell growth factor (GLS PD-ECGF) with other clinical markers of rheumatoid arthritis (RA) and to define its molecular mechanism of action in the complicated cytokine network during RA pathogenesis. Immunoassay systems were used to quantify GLS or cytokine levels in laboratory and clinical samples. Expression levels of GLS were determined by reverse transcription-polymerase chain reaction methods. The GLS levels in synovial fluid were correlated with interleukin-1 (IL-1) and IL-8. The serial data of serum GLS levels reflected well changes in the disease activity during the clinical course of four representative patients with RA. In cultured fibroblast-like synoviocytes, tumour necrosis factor-alpha (TNF-alpha), IL-1, IL-6 and IL-8 induced GLS expression. In conclusion, our results suggest that the serum GLS level, mostly derived from cytokine-stimulated synoviocytes, was a useful clinical marker of RA.

[Long-term changes in body mass index in rural inhabitants: Takasu study]

Based on community health examination data (1975-1992) of Takasu, a rural town in Hokkaido Prefecture, long-term changes in body mass index (BMI) were studied and contour maps were developed. The results were as follows: 1) A high median BMI, 23 or more, appeared in female age groups from 50's to 70's during the observation period, whereas the high median BMI appeared in male age groups 30's and 40's after 1981. 2) Median BMI in age groups 30's and 40's at the time of the initial observation increased gradually with age in both sexes.

[Longitudinal assessment of hematological parameters in the elderly]

Red blood cell count (RBC), hemoglobin level (Hb), hematocrit value (Ht), and white blood cell count (WBC) were determined periodically in 499 subjects (274 males, 225 females) aged 60 and over. RBC, Hb, and Ht showed a significant decrease after 5 years in both younger (60-64) and older (65 and over) male groups, and in the female groups except for the Hb level in the older group. Comparison between the younger and older group (cross-sectional study), revealed that the older male group showed lower levels of RBC, Hb, Ht than the younger male group, but the situation was completely the reverse in the females. No significant age-related changes were observed in WBC, but it was significantly higher in both the younger and older male groups than in the female groups. A significant decline with age was observed in both male and female MCV values. On the contrary, from a cross-sectional standpoint, the MCV values in the older female group were higher than those in the younger group. These findings revealed a completely reverse outcome in some parameters, when studied longitudinally and cross-sectionally. Therefore, the data should be evaluated longitudinally to elucidate the real effect of aging. It is pertinent to apply the WHO criteria (male 13 g/dl, female 12 g/dl) to the diagnosis of anemia of elderly people.