PubMed Health⌕ Search

Biomedical subjects

Yoshikazu Adachi

Publications and source records attributed to Yoshikazu Adachi.

18 recordsLinked to original sources

Comparative analysis of sesame lignans (sesamin and sesamolin) in affecting hepatic fatty acid metabolism in rats.

Effects of sesamin and sesamolin (sesame lignans) on hepatic fatty acid metabolism were compared in rats. Rats were fed either a lignan-free diet, a diet containing 0.6 or 2 g/kg lignan (sesamin or sesamolin), or a diet containing both sesamin (1.4 g/kg) and sesamolin (0.6 g/kg) for 10 d. Sesamin and sesamolin dose-dependently increased the activity and mRNA abundance of various enzymes involved in hepatic fatty acid oxidation. The increase was much greater with sesamolin than with sesamin. These lignans increased parameters of hepatic fatty acid oxidation in an additive manner when added simultaneously to an experimental diet. In contrast, they decreased the activity and mRNA abundance of hepatic lipogenic enzymes despite dose-dependent effects not being necessarily obvious. Sesamin and sesamolin were equally effective in lowering parameters of lipogenesis. Sesamolin accumulated in serum at 33- and 46-fold the level of sesamin at dietary concentrations of 0.6 and 2 g/kg, respectively. The amount of sesamolin accumulated in liver was 10- and 7-fold that of sesamin at the respective dietary levels. Sesamolin rather than sesamin can account for the potent physiological effect of sesame seeds in increasing hepatic fatty acid oxidation observed previously. Differences in bioavailability may contribute to the divergent effects of sesamin and sesamolin on hepatic fatty acid oxidation. Sesamin compared to sesamolin was more effective in reducing serum and liver lipid levels despite sesamolin more strongly increasing hepatic fatty acid oxidation.

Animals↗

Hemolysis resulting from surface roughness under shear flow conditions using a rotational shear stressor.

The degree of hemolysis as a function of surface roughness value and roughened area under shear flow conditions was investigated using a rotational shear stressor. The shearing portion of the stressor is cone shaped in its upper and lower positions, with a cylindrical central section. Surface roughness was applied to the cylindrical section. Bovine blood was sheared for 30 min over a set of roughened surfaces of between arithmetic mean roughness (Ra) 0.1 and 0.8 mm covering 10% of the surface area of the cylindrical section (equivalent to 1.8% of the whole blood contact area) at a shear rate of 3750/s. The threshold value thus obtained for rapid increase in hemolysis was between Ra 0.6 and 0.8 mm. When sheared with a roughened surface of Ra 0.8 mm applied to the cylindrical surface at areas between 0 and 100% (equivalent to between 0 and 18% of the whole blood-contacting area), the hemolysis level did not increase from 10 to 100%, but a significant difference was obtained between 0 and 10%. This suggests that red blood cells were destroyed not by fatigue failure caused by rolling on the roughened surface, but due to the high shear stress generated by surface roughness. Moreover, it appears that the shear stress was generated over the entire cylindrical section, regardless of the area of surface roughness.

Animals↗

The specific antibody to Brachyspira aalborgi in serum obtained from a patient with intestinal spirochetosis.

Serum obtained from a patient histopathologically diagnosed as intestinal spirochetosis was investigated serodiagnostically by agglutination test. B. aalborgi which is a human intestinal spirochete reacted strongly with the human serum, while B. pilosicoli which has potential pathogenicity to humans reacted with the serum, but as strongly and its titer was different than the other three species. On the other hand, intestinal spirochetes (Matsumoto isolates) were isolated from the biopsy samples of the patient. The morphological, biochemical, and genetic characteristics of the isolates were very similar to those of B. aalborgi. Furthermore, the protein profiles of the Matsumoto isolates were also similar to those of B. aalborgi but were different than those of B. pilosicoli and B. hyodysenteriae. The reaction profiles of the Matsumoto isolates in immunoblotting were relatively similar to those of B. aalborgi except for a 74 kDa band but were different from those of B. pilosicoli and B. hyodysenteriae. Therefore, we identified the Matsumoto isolates as B. aalborgi and diagnosed the patient with a B. aalborgi infection.

Agglutination Tests↗

Canine intestinal lactic acid bacteria agglutinated with concanavalin A.

Twenty-six out of 46 representative lactic acid bacteria (LAB) that we isolated from 36 dogs in a previous study were agglutinated by concanavalin A (ConA) at a concentration of 0.1563 mg/ml, while isolates did not agglutinate without the addition of ConA. Amongst the isolates, L. reuteri, L. mucosae, and E. canintestini agglutinated strongly, while L. gallinarum, L. kitasatonis, L. acidophilus, L. saerimneri, B. animalis ssp. animalis, P. acidilactici, and E. hirae did not agglutinate. ConA-agglutination of LAB was specifically inhibited by D-glucose, D-galactose, and D-mannose at a concentration of 1.563 mg/ml. Among the sugars, ConA-agglutination was strongly inhibited by D-mannose, while the inhibition level by D-glucose and D-galactose were lower than that of D-mannose. ConA- agglutination of all the LAB isolates was inhibited by D-mannose, except for L. reuteri (one species) and L. mucosae (two species). ConA-agglutination of Bifidobacterium spp. was inhibited by only D-mannose. Based on our results, ConA-agglutination of LAB seems to be strain-specific, but not species-specific.

Agglutination Tests↗

Morphometry on lancet flukes found in Japanese sika deer (Cervus nippon centralis) captured in Iwate Prefecture, Japan.

Thirty-six flukes were collected from the livers of wild deer (Cervus nippon centralis) captured in Iwate Prefecture, Japan, and were served for morphometry. The length and/or the width of the body, suckers, testes, ovary, vitelline glands, cirrus pouch and eggs in the uterus of the flukes were measured. The distance between anterior end of the body and position of the maximal body-width or upper end of the testes were also determined. A remarked morphological characteristic was that the right and left testes did not lie tandem but lined bilaterally. Also the position of the maximal body-width did not always locate in the posterior part of the body of the fluke. The property was in accordance with those for Dicrocoelium chinensis.

Animals↗

Effects of griseoviridin and viridogrisein against swine dysentery in experimental infection by using mice and pigs.

Griseoviridin, a known antibiotic produced by Streptomyces cacaoi subsp. cacaoi, was found to be active against Brachyspira hyodysenteriae--the bacterium causing swine dysentery. An in vitro synergism is observed when it is used in combination with viridogrisein--a simultaneously produced antibiotic. In mouse experiments, the effect of griseoviridin alone was less than that of lincomycin--a commercially available swine dysentery medication. However, a 1:1 mixture of griseoviridin and viridogrisein revealed a noticeable synergistic effect. In an evaluation using pigs artificially infected with B. hyodysenteriae, a large difference was not observed between the effect of griseoviridin alone and that in combination with viridogrisein. Nevertheless, griseoviridin alone exhibited a therapeutic effect superior to that of lincomycin.

Animals↗

Comparison of immunoblot analysis of emergent multidrug-resistant Salmonella typhimurium definitive phage type 104 with a non-multidrug-resistant definitive phage type 104 strain.

BACKGROUND AND PURPOSE: The emergent multidrug-resistant (MDR) Salmonella typhimurium definitive phage type 104 (DT104) is a public and veterinary health problem not only due to its wide host range and potential for enhanced virulence, but also the difficulty associated with its control. There is thus a need to investigate possible antigens of MDR DT104. METHODS: Using standard protocols, whole cell lysates, outer membrane extracts and cell-free ultracentrifuge supernatants of selected isolates of MDR DT104 were prepared, electrophoretically separated and tested for their antigen-antibody reactivity in comparison with a non-MDR DT104 strain. RESULTS: Protein antigens of both strain types were recognized by antibodies in chick serum in a similar manner for all methods of antigen preparation used. CONCLUSIONS: This study did not find differences between the antibody recognition of MDR DT104 and that of the non-MDR DT104 strain tested. This observation should strengthen the quest for the possible use of vaccines to control this emergent strain in poultry.

Animals↗

Characterization of biofilm-forming abilities of antibiotic-resistant Salmonella typhimurium DT104 on hydrophobic abiotic surfaces.

BACKGROUND AND PURPOSE: Salmonella typhimurium DT104 strain has emerged as a global human and veterinary public health concern because of its antibiotic resistance and extensive host range. Although it is thought to be more virulent, to date, factors relevant to its virulence have not been fully elucidated. Thus, understanding how this strain forms biofilms on hydrophobic surfaces will add to current knowledge on its possible virulence mechanism. METHODS: Biofilm-forming abilities of clinical isolates of S. typhimurium DT104 from human and animal sources on hydrophobic inanimate surfaces were assessed by absorbance at 600 nm of crystal violet-bound cells recovered from 96-well tissue culture plates after growth in a nutrient-rich growth medium and various adjusted media; and scanning electron microscopy based on standard procedures. RESULTS: In the nutrient-rich growth medium, Luria-Bertani (LB), biofilms were formed in small quantities, preferentially on polystyrene (p<0.05), and followed different time courses. Significantly lower amounts of biofilms were formed on polystyrene when a nutrient-deficient growth medium (adherence test medium) was used. Inclusion of D-(+)-mannose in LB at a concentration of 100 mM significantly (p<0.05) inhibited biofilm formation on polystyrene. D-(+)-glucose relatively enhanced biofilm formation but D-(-)-mannitol only insignificantly influenced the process. The action of mannose on polyvinly chloride (PVC) was insignificant, suggesting that its action may be surface-dependent. Additionally, glucose significantly reduced biofilm growths of 2 of the isolates and only that of the PVC-loving strain T980021 on polystyrene and PVC, respectively. At the concentration tested, unlike xylose, both D-mannose and D-glucose significantly (p<0.05) inhibited bacterial growth, providing a possible mechanism for their inhibitory action on biofilm formation by S. typhimurium. While stress of starvation resulted in significant reduction in biofilm formation on polystyrene in all but the PVC-loving strain T980021, high osmolarity had little effect on the quantity of biofilm formed on polystyrene. The extent of primary attachment to polystyrene as well as their capacity to form biofilm did not correlate with their cell surface hydrophobicity and exopolysaccharide production. CONCLUSIONS: D-(+)-mannose inhibits biofilm formation by S. typhimurium DT104 on polystyrene but not on PVC. There was also a general lack of correlation between the ability of S. typhimurium DT104 to form biofilm and its physicochemical surface characteristics.

Animals↗

Hemolysis caused by surface roughness under shear flow.

In this study, the relationship between the degree of roughness of blood contact surfaces under laminar shear flow conditions and the level of hemolysis resulting from this roughness was investigated using a rotational shear stressor. Unlike previous in vitro experiments that used a pumped circuit, the level of hemolysis was directly evaluated under a constant shear flow. In total, 1.8% of the blood contact area was roughened to an arithmetic mean roughness (Ra) value of between 0.4 and 9.2 microm by machine processing and a shear load was applied for 30 min at a shear flow rate of 3750 s(-1). As a result, the threshold Ra value for the induction of hemolysis was found to be between 0.4 and 0.8 microm. In addition, the results of this experiment suggested that the high shear stress resulting from surface roughness plays a major role in determining the level of hemolysis caused by surface roughness.

Animals↗

Intestinal microflora in 45 crows in Ueno Zoo and the in vitro susceptibilities of 29 Escherichia coli isolates to 14 antimicrobial agents.

Microorganisms from 45 jungle crows (Corvus macrorhynchos) captured from July to December 2002 at Ueno Zoo, Tokyo were identified as Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Enterobacter agglomerans, Pseudomonas maltophila, Staphylococcus spp., Micrococcus spp., and Streptococcus spp. E. coli showed the highest rate of isolation (21.6%). In an in vitro susceptibility test for 29 isolates of E. coli to 14 antimicrobial agents, all the isolates were resistant to penicillin G, vancomycin, erythromycin, lincomycin, bicozamycin, sulfadimethoxine, and olaquindox. Several isolates of them were also resistant to tetracycline, oxytetracycline, streptomycin, chloramphenicol, and ampicillin. Twenty-nine isolates were divided into 19 serogroups and the most frequently identified serogroups were O8, O114 and O144, which showed the same multidrug-resistant patterns.

Animals↗

In vitro susceptibility of 21 antimicrobial agents to 37 isolates of Brachyspira hyodysenteriae isolated from pigs in Okinawa Prefecture.

The in vitro susceptibilities to 21 antimicrobial agents, of 37 isolates of Brachyspira (B.) hyodysenteriae isolated from pigs in Okinawa meat center and a pig farm in Okinawa Prefecture, Japan, were determined by the agar dilution method. Carbadox was the most active of all the agents tested against the isolates (MIC: <0.003 to 0.05). All the isolates were highly susceptible to olaquindox, tiamulin, dimetridazole, efrotomycin and valnemulin with MICs ranging from </=0.1 to 1.6 microg/ml. Penicillins, chloramphenicol, tetracyclines, terdecamycin and streptomycin were also active against the isolates. Most isolates were resistant to lincomycin, avilamycin and macrolides (with the exception of terdecamycin).

Animals↗

Brachyspira pilosicoli isolated from two beagles and one mongrel in Japan.

The feces, colonic contents, and colonic mucosa from two beagles and a mongrel with and without mucohemorrhagic diarrhea were anaerobically cultured and after 72 hr, lucent and rough colonies with weak beta-hemolysis were observed. Small spirochetes with one or two loose waves in the colonies were observed under a phase contrast microscope and the spirochete cells sometimes aggregated. The 16SrDNA sequencing results demonstrated that the canine isolates were B. pilosicoli and the base alignments registered in DDBJ. This is the first report concerning the isolation of B. pilosicoli from dogs in Japan.

Animals↗

A possibility of application of the 105-kilodaltons protein of Brachyspira alvinipulli cross-reacting with antisera to five species in the genus Brachyspira to diagnosis.

The antigenic properties of Brachyspira (B.) alvinipulli ATCC 51933 and strain C2 were analyzed and compared with those of B. hyodysenteriae ATCC 27164 and ATCC 31212, B. pilosicoli ATCC 51139, B. innocens ATCC 29796 and B. aalborgi NCTC 11492. In gel immunodiffusion tests, a protein in B. alvinipulli ATCC 51933 reacted strongly with anti-B. alvinipulli ATCC 51933-serum and formed two precipitin lines. Furthermore, by an immunoblotting technique, the 105-kilodaltons (kDa) protein in B. alvinipulli ATCC 51933 reacted strongly with each of the antisera to B. hyodysenteriae, B. pilosicoli, B. innocens and B. aalborgi. Therefore, the 105-kDa protein could be applied to diagnosis of chicken infection by B. alvinipulli and B. pilosicoli. But the 105-kDa protein reacting with the anti-B. alvinipulli ATCC 51933-serum was not confirmed in B. hyodysenteriae, B. pilosicoli, B. innocens and B. aalborgi. The N-terminal amino acid sequence of the 105-kDa protein isolated from B. alvinipulli ATCC 51933 was Met-Lys-Lys-Met-Val-Tyr-Phe-Phe-Gly-Asn. The amino acid alignment of this protein possessed 50% homology with the periplasmic-iron-binding protein BitC in B. hyodysenteriae.

Animals↗

Brachyspira pilosicoli isolated from pigs in Japan.

Two of four weak beta-hemolytic isolates of intestinal spirochetes isolated from pigs in Japan possessed a unique base alignment of TTTTTT on the 16S ribosomal DNA of Brachyspira pilosicoli and were identified as B. pilosicoli. The other two isolates were not identified by this technique. The identified isolates were 4.2 to 11 microm in length and 0.2 to 0.3 microm in diameter, 4 periplasmic flagella at each end were observed dominantly. The isolates were hippurate positive but indole negative. This is the first report on the isolation of B. pilosicoli from pigs in Japan.

Animals↗

Morphological properties of a human intestinal spirochete first isolated from a patient with diarrhea in Japan.

A human intestinal spirochete isolated from a rectal biopsy specimen was morphologically characterized. The isolate was comma-shaped, 3-6 microm in length, 0.2 micro m in diameter and had tapered ends. The surface layer, external to the outer envelope, was amorphous. Four string-like periplasmic flagella with a diameter of 20 nm were presented at each end of the SDS-treated cells. Thin sections of the bacterial cell revealed a high-density cytoplasmic membrane and flagella in the periplasmic space between the cytoplasmic membrane and the outer envelope. Three segments of equal length were observed in some of the cells, while other cells were bi-segmented and more frequently observed.

Biopsy↗

In vitro susceptibility and a new point mutation associated with tylosin-resistance in Japanese canine intestinal spirochetes.

The in vitro susceptibilities of six commonly used antimicrobial agents against 29 isolates of intestinal spirochetes isolated from dogs in Japan were examined by the agar dilution technique. In addition, the genetic basis of tylosin resistance in in vitro selected resistant mutants of two reference strains and three tylosin-susceptible field isolates obtained by three successive subcultures on blood agar containing 1 microg/ml of tylosin was investigated. Carbadox was the most active (MIC: < 0.00625) of all the antimicrobial agents. Although all the isolates were susceptible to tylosin, some were resistant to erythromycin. Tiamulin, lincomycin and dimetridazole were also very active against the isolates. All the resistant isolates did not harbor any plasmids. In vitro selected tylosin-resistant mutants of previously tylosin-susceptible isolates showed a new mutation in which their adenine at the base position equivalent to 2062 of 23S rDNA of Escherichia coli has been replaced by cytosine. These findings may both provide guidance towards the proper choice of antimicrobial agents for the treatment of canine intestinal spirochetosis, and add to the understanding of the genetic basis of tylosin resistance.

Animals↗

Serological survey of leptospirosis in sows with premature birth and stillbirth in Chiba and Gunma prefectures of Japan.

In 1996 and 1997, the seroprevalence against Leptospira in parturient sows with premature birth or stillbirth from two herds was investigated. In three out of four sow serum samples obtained in Gunma Prefecture, the antibody titers to Leptospira interrogans serovar copenhageni (M20) were higher than 10,000 (the reciprocal of the serum dilution). Furthermore, the antibody titers to L. interrogans serovar canicola (Hond Utrecht IV) were significantly high in the three sows and the titers ranged from 1,000 to 3,000. In sows obtained in Chiba Prefecture, significantly high antibody titers to serovar copenhageni (M20) were confirmed in eight out of 40 sows, and antibody titers greater than 10,000 in six of them. Significantly high antibody titers to L. interrogans serovar icterohaemorrhagiae (RGA) and L. canicola (Hond Utrecht IV) were confirmed in four and 18 out of the 40 sows, respectively, compared with the titers to the other serovars. These findings may indicate the prevalence of leptospirosis in pig herds in both Gunma and Chiba Prefectures.

Abortion, Veterinary↗