In vitro effects of malathion and O,O,S-trimethyl phosphorothioate on cytotoxic T-lymphocyte responses

Oral administration of O,O,S-trimethyl phosphorothioate (OOS), an impurity present in technical formulations of malathion, has been shown to be associated with a high incidence of pneumonia in rats and to be highly immunosuppressive in mice. Based on these findings, an in vitro model was established to study the effect of this and other organophosphorus compounds on murine cytotoxic T-lymphocyte (CTL) responses. The organophosphorus compounds were tested for their ability to block in vitro generation of CTL responses to alloantigen and/or the expression of these cytotoxic responses. Responses were generated in C57Bl/6 (H-2^b) spleen cells to mitomycin C-blocked P815 (H-2^d) tumor cells. The cytotoxicity of the cultured splenocytes to P815 target was measured using a 4-hr chromium release assay. These data demonstrated that malathion was able to block the ability of splenocytes to sensitize to P815 at concentrations as low as 25 μg/ml, but was not able to block the expression of cytotoxicity by mature killer T cells. The same was true for OOS which had been activated by preincubation with rat liver postmitochondrial supernatant (PMS). Activated OOS blocked the generation of CTL responses at concentrations as low as 75 μg/ml while having no effect on mature cytotoxic cells. In fact, both malathion and activated OOS were no longer able to suppress CTL responses if treatment was performed as early as 24 hr after exposure to antigen. Additionally, it was demonstrated that when malathion was preincubated with PMS it was no longer suppressive and that OOS without activation failed to suppress CTL responses.     

Microdroplet In Vitro Fertilization Can Reduce the Number of Spermatozoa Necessary for Fertilizing Oocytes

Successful in vitro fertilization (IVF) in mice has been achieved using spermatozoa at concentrations specifically optimized for the experimental conditions, such as species and source of spermatozoa. Although IVF in mice is mostly performed using about 80–500 µl drops, it is expected that the number of spermatozoa used for insemination can be reduced by decreasing the size of the IVF drops. The present study was undertaken to examine the extent to which the number of spermatozoa used for IVF could be reduced by using small droplets (1 µl). We devised the experimental parameters using frozen–thawed spermatozoa from C57BL/6 mice in anticipation of broader applications to other mouse facilities. We found that as few as 5 spermatozoa per droplet could fertilize oocytes (1 or 3 oocytes per droplet), although the fertilization rates were low (13–15%). Practical fertilization rates (> 40%) could be achieved with frozen-thawed C57BL/6J spermatozoa, which are sensitive to cryopreservation, when 20 sperm per droplet were used to inseminate 3 oocytes. Even with spermatozoa from a very poor quality suspension (10% motility), about 25% of oocytes were fertilized. Our calculations indicate that the number of inseminated spermatozoa per oocyte can be reduced to 1/96–1/240 by this method. In two separate embryo transfer experiments, 60% and 47%, respectively, of embryos developed to term. Our microdroplet IVF method may be particularly advantageous when only a limited number of motile spermatozoa are available because of inadequate freezing-thawing or genetic reasons.     

A new source of basaltic meteorites inferred from Northwest Africa 011

Eucrites are a class of basaltic meteorites that share common mineralogical, isotopic, and chemical properties and are thought to have been derived from the same parent body, possibly asteroid 4 Vesta. The texture, mineralogy, and noble gas data of the recently recovered meteorite, Northwest Africa (NWA) 011, are similar to those of basaltic eucrites. However, the oxygen isotopic composition of NWA011 is different from that of other eucrites, indicating that NWA011 may be derived from a different parent body. The presence of basaltic meteorites with variable oxygen isotopic composition suggests the occurrence of multiple basaltic meteorite parent bodies, perhaps similar to 4 Vesta, in the early solar system.     

ENDOSCOPIC ULTRASONOGRAPHY OF THE PANCREAS IN THE DOG

Endoscopic ultrasonography was done in 12 normal adult dogs to investigate its efficacy in visualization of the pancreas. The endoscopic ultrasonographic device used in the present study had a curved-array ultrasound transducer mounted in front of the objective lens. The tip of the ultrasonic endoscope was inserted into the stomach, and all examinations of the pancreas were performed from within the stomach. Endoscopic ultrasonography provided good images of most parts of the pancreas except for the ends of each lobe. Useful information about the pancreatic parenchyma, including pancreatic lobular structure, pancreatic duct, and vessels of the pancreas was obtained by endoscopic ultrasonography. Blood flow within vessels was detected using color Doppler and pulsed-wave Doppler examination. These results suggest that endoscopic ultrasonography is available as an effective diagnostic modality in small animal practice.     

New anthraquinone glycosides from the roots of Morinda citrifolia

Six new anthraquinone glycosides: digiferruginol-1-methylether-11-O-β-gentiobioside (1); digiferruginol-11-O-β-primeveroside (2); damnacanthol-11-O-β-primeveroside (3); 1-methoxy-2-primeverosyloxymethyl-anthraquinone-3-olate (4); 1-hydroxy-2-primeverosyloxymethyl-anthraquinone-3-olate (5); and 1-hydroxy-5,6-dimethoxy-2-methyl-7-primeverosyloxyanthraquinone (6) were isolated from Morinda citrifolia (Rubiaceae) roots together with four known anthraquinone glycosides. The structures of the new compounds were established using spectral methods. For five of the new compounds, the sugar is attached via the hydroxymethyl group of the anthraquinone C-2 carbon. This type of bond is rarely found for anthraquinone glycosides isolated from natural sources.     

Corynespora leaf spot of scarlet sage caused by <Emphasis Type="Italic">Corynespora cassiicola</Emphasis>

A leaf spot disease of scarlet sage (Salvia splendens Sellow ex J.A. Shultes) found in Kanagawa and Tokyo prefectures was demonstrated to be caused by Corynespora cassiicola (Berk. and Curt.) Wei based on inoculation experiments, and morphological identification of the pathogenic fungus. Isolates of C. cassiicola from cucumber, green pepper, and hydrangea were also pathogenic to scarlet sage leaves. Although the isolates from cucumber, green pepper, and hydrangea were pathogenic to scarlet sage leaves, the scarlet sage isolate was not pathogenic to cucumber, green pepper, hydrangea, eggplant, tomato or soybean.     

Chemical constituents of Baeckea frutescens leaves inhibit copper-induced low-density lipoprotein oxidation

Oxidative modification of LDL plays an important role in the genesis of arteriosclerosis. This study focused on the effects of the leaves of Baeckea frutescens in the prevention of arteriosclerosis. The leaves of B. frutescens have afforded, besides known flavonoid and chromone glycosides, a novel biflavonoid glycoside, characterized as 3-O-α-l-rhamnopyranosylmyricetinyl-(I-2″,II-2″)-3-O-α-l-rhamnopyranosylmyricetin on the basis of chemical and spectral evidence. This compound exhibited marked inhibition of copper-induced LDL oxidation.     

Alternaria Leaf Spot on Three Species of Pelargonium Caused by Alternaria alternata in Japan

A new disease of pelargonium (Pelargonium domesticum Bailey), ivy geranium (P. peltatum (L.) L'Hér. ex Ait.) and scented geranium (P. graveolens L'Hér.), primarily causing brown spots on leaves, was found in Kawasaki-shi in Kanagawa Prefecture and Tachikawa-shi in Tokyo. An Alternaria sp. was consistently isolated from these diseased leaves, and the isolates were pathogenic to their host leaves. Based on morphological characteristics, the causal fungus in all three cases was identified as Alternaria alternata (Fr.) Keissler. Because Alternaria leaf spot of geranium by A. alternata has already been reported, the pathogenicity of isolates from four groups of genus Pelargonium was investigated. The isolates from scented geranium were pathogenic only to their original host, but the isolates from pelargonium, ivy geranium and geranium were pathogenic to all groups of pelargonium. This is the first report of this disease on pelargonium, ivy geranium and scented geranium caused by A. alternata in Japan. We propose the names for these diseases as Alternaria leaf spot of pelargonium (kappan-byo), Alternaria leaf spot of ivy geranium (kappan-byo) and Alternaria leaf spot of scented geranium (kappan-byo). Received 11 December 2000/ Accepted in revised form 19 July 2001     

2-arylalkanoates,a new group of synthetic pyrethroid esters not containing cyclopropanecarboxylates

Although structure modifications of natural pyrethrin constituents have disclosed a variety of potent synthetic analogues, all known examples are cyclopropanecarboxylate esters, a grouping that appeared to be essential for insecticidal activity. Some new substituted 2-phenylalkanoates, whose biological activities are of a similar nature and potency to those of conventional pyrethroids, are now reported. 5-Benzyl-3-furylmethyl and 3-phenoxybenzyl 3-methyl-2-phenylbutyrates and their analogues are potent insecticides. Activity is increased on the introduction of appropriate groups into the 3 and/or 4-positions of the aryl ring and the (S)-2-phenylalkanoates are far more active than their (R)-enantiomorphs. Structure/activity relationships are compared with those for conventional pyrethroids. Some of the new series compare favourably with typical insecticides in tests against Musca domestica, Spodoptera litura and Plutella xylostella.