Mapping of Col3a1 and Col6a3 to proximal murine chromosome 1 identifies conserved linkage of structural protein genes between murine chromosome 1 and human chromosome 2q

We have investigated the degree of synteny between the long arm (q) of human chromosome 2 and the proximal portion of mouse chromosome 1. To define the limits of synteny, we have determined whether mouse homologs of seven human genes mapping to chromosome 2q cosegregated with anchor loci on mouse chromosome 1. The loci investigated were NEB/Neb, ELN/Eln, COL3A1/Col3a1, CRYG/Len-2, FN1/Fn-1, VIL/Vil, and COL6A3/Col6a3. Ren-1,2 and Acrg were included as two proximal mouse chromosome 1 anchor loci. The segregation of restriction fragment length polymorphisms at these loci was analyzed in the progeny of Mus spretus x C57BL/6J hybrids backcrossed to the C57BL/6J inbred strain. We found that five of the structural protein loci and the two anchor loci form a linkage group on proximal murine chromosome 1. The proposed gene order of this group of linked markers is centromere - Col3a1 - Len-2-Fn-1-Vil-Acrg-Col6a3-Ren1,2. Neb and Eln are linked neither to each other nor to any other marker on proximal mouse chromosome 1. Therefore, the mouse loci Col3a1 and Col6a3 are identified as flanking markers of the linkage group of structural protein loci. The estimated genetic map distances are Col3a1-13.3 cM-Len-2-3.4 cM-Fn-1-3.8 cM-Vil-9.6 cM-Acrg-2.1 cM-Col6a3-18.3 cM-Ren1,2. The available map information for human chromosome 2q markers and mouse chromosome 1 markers presented here tentatively identifies Col3a1 and Col6a3 as the border markers that define the limits of the syntenic chromosome segment. The order of mouse genes on chromosome 1 and their human homologs on chromosome 2q also appears to be conserved, suggesting that mapping of murine genes on the conserved segment may be useful to predict gene order in man.     

Cross-reactivity of antibodies against T-2 with deepoxide T-2 toxin

Two types of antibodies raised against T-2 toxin, namely anti-T-2-HS-BSA and anti-3 -Ac -NEOS-HS -BSA, showed good cross-reactivity with deepoxy T-2 toxin. Our results indicate that the epoxide is not an important epitope for the production of antibody against T-2 toxin     

A scanning electron microscope study on the tegument of Proalarioides kobayashii Park, 1940 (Trematoda)

A SEM study was performed on the surface of adult P. kobayashii Park, 1940, recovered from the snake, Elaphe rufodorsata. The anterior part of the worms was cup-shape and equipped with oral, ventral suckers, pseudosuckers, and tribocytic organ, and the posterior one was finger-like and round-ended. The tegument of the anterior body was covered with 3-4 pointed small spines on the mid-ventral surface and 1-2 pointed ones on the lateral surface. Sensory papillae such as type II, dome-shape ones, and papillae with an opening were distributed over the ventral surface of the anterior portion. The round tribocytic organ was bearing small stout spines laterally, whereas the surface which comes in contact with the host tissues consisted of numerous long fibrillar fibers. The lip of the oral sucker contained type II papillae. Lateral margin of the anterior body revealed type III papillae.     

Mycotoxins: food contamination, mechanism, carcinogenic potential and preventive measures

Mycotoxins constitute a large number of naturally occurring fungal secondary metabolites with very diversified toxic effects in humans and animals. Among many mycotoxins discovered, aflatoxins, ochratoxin A, sterigmatocystin and several others are identified as carcinogens; several others were found to be mutagenic. Nevertheless, aflatoxin B1 has been found to be one of the most potent carcinogens and contamination of aflatoxins in the food supply is still a major concern. Whereas extensive studies have been made on aflatoxins, little is known about the mode of action of other carcinogenic and mutagenic mycotoxins. Recent progress on research for the carcinogenic and mutagenic mycotoxins is presented in this review with emphasis on their contamination in foods, their carcinogenic potential to humans, and the mode of action as well as possible preventive measures.     

Changes in soil microflora associated with control of Sclerotium Rolfsii by Furfuraldehyde

The efficacy of 2‐furfuraldehyde for control of Sclerotium rolfsii was studied in laboratory and greenhouse experiments. Mycelial growth of the fungus was reduced proportionally with concentrations of 0.1–0.5 ml furfuraldehyde l^‐1 agar medium, and viability of sclerotia diminished on exposure to 2‐furfuraldehyde vapours. Detectable populations of bacteria and fungi, including Trichoderma spp., were reduced significantly (9=0.05) when furfuraldehyde was added to the agar used for soil dilution plates of untreated soil. Repeated treatments of natural soil with the fumigant significantly increased populations of Trichoderma spp. and bacteria, but diminished numbers of actinomycetes. Increasing dosages applied to soil artificially infested with S. rolfsii caused a reduction of disease on lentil, Lens culinaris. Results indicate that the compound, when applied to field soil, changes the composition of soil microflora and has potential for integrated control of S. rolfsii.     

A Comparison of the Efficacy of Nuclear Polyhedrosis and Granulosis Viruses in Spray and Bait Formulations for the Control of Agrotis segetum (Lepidoptera: Noctuidae) in Maize

Agrotis segetum nuclear polyhedrosis virus (AsNPV) and granulosis virus (AsGV), propagated in laboratory cultures of A. segetum in England and A. ipsilon in Spain, respectively, were applied to plots of maize plants at the one‐ to four‐leaf stage of growth. Plots were arranged in a 6 x 6 Latin square design and infested with second‐instar A. segetum larvae (the common cutworm). Each virus was applied in separate treatments by two application methods; as an aqueous spray containing 0.1% Agral as a wetting agent, and as a bran bait. The NPV was applied at a rate of 4 X 10¹² polyhedra/ha, and the GV at 4 X 10¹³ granules/ha. Soil and plants were sampled for larvae on three occasions following virus treatment: 24 h, 4 days and 11 days. The larvae were reared on diet in the laboratory, until death or pupation, to examine the rate and level of viral infection. Infection data showed 87.5% and 91% NPV infection and 12.5% and 55% GV infection in spray and bait treatments, respectively, in larvae sampled 24 h after treatment. In larvae sampled 4 days after treatment, the results were 78% and 100% NPV infection, and 13% and 6% GV infection. A total of only six larvae were retrieved on day 11. In both treatments larvae infected with AsNPV died significantly more rapidly and at an earlier instar than those infected with AsGV, indicating that AsNPV appears to have better potential as a control agent for A. segetum.     

The expression of ceruloplasmin, an angiogenic glycoprotein, by mouse embryonic fibroblasts

Balb/c 3T3, Swiss 3T3 and Rous sarcoma virus transformed Balb/c 3T3 mouse embryonic fibroblasts produced ceruloplasmin in vitro, whereas primary cultures prepared from the Balb/c mouse embryos did not produce ceruloplasmin. The amount of ceruloplasmin synthesis by the Balb/c 3T3 cell line is enhanced by Rous sarcoma virus-transformation (1.5-3 fold) and by treatment with dexamethasone (about 2.4 fold). The protein was identified as ceruloplasmin by immunoprecipitation with ceruloplasmin-specific polyclonal antibody, and by similarity of peptide maps, and subunit molecular weight (135,000 dalton) to that of authentic ceruloplasmin from primary cultures of mouse hepatocytes.     

Cloning and DNA sequence of a plasmid-determined citrate utilization system in Escherichia coli.

The citrate utilization determinant from a large 200-kilobase (kb) naturally occurring plasmid was previously cloned into the PstI site of plasmid vector pBR325 creating the Cit+ tetracycline resistance plasmid pWR61 (15 kb). Tn5 insertion mutagenesis analysis of plasmid pWR61 limited the segment responsible for citrate utilization to a 4.8-kb region bordered by EcoRI and PstI restriction nuclease sites. The 4.8-kb fragment was cloned into phage M13, and the DNA sequence was determined by the dideoxyribonucleotide method. Within this sequence was a 1,296-base-pair open reading frame with a preceding ribosomal binding site. The 431-amino-acid polypeptide that could be translated from this open reading frame would be highly hydrophobic. A second long open reading frame with the potential of encoding a 379-amino-acid polypeptide preceded the larger open reading frame. Portions of the 4.8-kb fragment were further subcloned with restriction endonucleases BglII and BamHI, reducing the minimum size needed for a citrate-positive phenotype to a 1.9-kb BamHI-BglII fragment (which includes the coding region for the 431-amino-acid polypeptide, but only the distal 2/3 of the reading frame for the 379-amino-acid polypeptide). Citrate utilization results from a citrate transport activity encoded by the plasmid. With the 4.8-kb fragment (as with larger fragments) the citrate transport activity was inducible by growth on citrate. On transfer from glucose, succinate, malate, or glycerol medium to citrate medium, the Cit+ Escherichia coli strains showed a delay of 36 to 48 h before growth.