Eitaro Hori

Involvement of IL-2/IL-2R system activation by parasite antigen in polyclonal expansion of CD4(+)25(+) HTLV-1-infected T-cells in human carriers of both HTLV-1 and S. stercoralis.

The intermediate state of HTLV-1 infection, often found in individuals dually infected with Strongyloides stercoralis (S. stercoralis) and HTLV-1, is assumed to be a preleukemic state of adult T-cell leukemia (ATL). To investigate the effects of S. stercoralis superinfection on the natural history of HTLV-1 infection, we characterized peripheral blood samples of these individuals in Okinawa, Japan, an endemic area for both HTLV-1 and S. stercoralis and we studied effects of the parasite antigen on T-cells. The dually infected individuals showed a significantly higher provirus load and an increase in CD4+25+ T cell population, with a significant, positive correlation. This increase was attributable to polyclonal expansion of HTLV-1-infected cells, as demonstrated by inverse-long PCR analysis of the integration sites. S. stercoralis antigen activated the IL-2 promoter in reporter gene assays, induced production of IL-2 by PBMC in vitro, and supported growth of IL-2 dependent cell lines immortalized by HTLV-1 infection or the transduction of Tax. Taken collectively, these results indicate that S. stercoralis infection induces polyclonal expansion of HTLV-1-infected cells by activating the IL-2/IL-2R system in dually infected carriers, an event which may be a precipitating factor for ATL and inflammatory diseases.

Inhibition of flight in Periplaneta americana (Linn.) by a trehalase inhibitor, validoxylamine A

Abstract Male adults of Periplaneta americana were graded into three groups according to their flight activity; very active (continuous flight longer than 5 min), active (1–5 min) and inactive (shorter than 1 min). 1H-NMR analysis showed that approx. 30 mM trehalose was present in the haemolymph of each of the above categories of untreated cockroaches. After exhaustive flight, the haemolymph trehalose concentration in very active individuals decreased to 2.5 min. The trehalase activity of the flight muscle was inhibited about 70% and the haemolymph trehalose concentration increased to about 3 times the normal level without change in the other haemolymph components. Trehalose also accumulated in the tissues of the cockroaches injected with validoxylamine A. These observations suggest that validoxylamine A inhibits the muscle trehalase and prevents the use of trehalose as a source of energy for flight.

Occurrence of high ratio of males after introduction of minocycline in a colony of leptotrombidium fletcheri infected with orientia tsutsugamushi

In colonies of Leptotrombidium fletcheri mites infected with Orientia tsutsugamushi (Ot), the agent of scrub typhus, males rarely appear. In the present study, the development of a high ratio of males was observed after introduction of minocycline (MC). A high dose of MC was injected subcutaneously into a mouse, and by feeding unfed larvae from an infected mite colony on this mouse, the Ot in the mites were successfully killed. Of a total of 130 unfed larvae attached to the mouse, 29 developed into females; of these, 9 laid an average of 112.4 eggs/female. Unfed larvae in the succeeding generations were attached to untreated mice. All adults in the P and F1 generations were females, and males started to appear at the F2 generation. The ratio of males to females was 332:7, 108:13, 263:61 and 71:9 at the F2, F3, F4 and F5 generations, respectively. These data suggest that Ot in the ovary or gonad may suppress the development of males.

Increased cerebral choline-compounds in Duchenne muscular dystrophy.

WE investigated the hypothesis that cell membrane function is abnormal in brains of subjects with Duchenne muscular dystrophy (DMD) using proton-nuclear magnetic resonance (NMR) spectroscopy of human brain extracts. The total amount of choline-containing compounds was significantly higher (about three times) than in normal controls and patients with other myopathies, while N-acetyl-L-aspartic acid and creatine were within the normal range. These findings indicate that abnormal cell membrane function may be correlated with the abnormal dystrophin or lack of dystrophin in the brain of patients with DMD.

Electron Microscopic Observations of the Embryo Leptotrombidium (Leptotrombidium) pallidum Naturally Infected with Rickettsia tsutsugamushi

Embryos of Leptotrombidium (Leptotrombidium) pallidum mites naturally infected with Rickettsia tsutsugamushi were examined by electron microscopy. Rickettsiae were not found in eggs just after oviposition, but were easily detected in cells at the various parts of the embryos just before hatching, indicating that the rickettsiae are surely vertically transmitted from infected adult mites to the larvae through embryos, and the rickettsiae may multiply in situ during the developing process of the embryo.

1H- and 13C-NMR spectroscopic study of the metabolites in young adult Angiostrongylus cantonensis maintained in vitro

1H- and 13C-nuclear magnetic resonance (NMR) spectroscopy were used to study metabolites excreted by young adult Angiostrongylus cantonensis maintained aerobically in the presence of D-[13C6]glucose. End-products of glucose metabolism identified and quantitated by means of 1H-NMR were lactate, acetate and alanine, in the molar ratio of 1:0.13:0.05 for males and 1:0.07:0.04 for females. 13C-NMR analyses proved that all the three products originated from the glucose present in the medium.

Morphology and identification of Chrysops larvae from Nigeria

Abstract. Mature larvae of four Afrotropical species of Chrysops (Diptera: Tabanidae): C.centurionis Austen, C.distinctipennis Austen, C.longicornis Macquart and C.silaceus Austen, are decribed and illustrated from specimens collected in Nigeria, identified by rearing associated adult flies. The descriptions pay special attention to the value of ultrastructural characters, such as cuticular striations, observed by scanning electron microscopy (SEM).

13C and 31P NMR spectroscopic studies on glucose metabolism in Tribolium confusum

Nuclear magnetic resonance (NMR) technology was applied to study the glucose metabolism in Tribolium confusum (Coleoptera). 13C signals of D‐(1‐13C)glucose eaten by beetles were clearly detected in such metabolites of the glucose metabolism as glycogen, trehalose, triacylglycerol, alanine and proline by 13C‐NMR. After glucose feeding the 31P‐NMR spectra of T. confusum showed the signal intensity increases in arginine‐phosphate, sugar‐phosphate and uridine diphosphoglucose. The results demonstrated the potential of NMR analysis for the study of glucose metabolism in T. confusum.