Comparison of chemical analyses of boat and helicopter-collected water samples

Helicopters can be used to collect water samples from many lakes over a wide geographic area within a relatively short time period. Here we report the results from an experiment in which sequential water samples from a lake were collected first from a nonmotorized boat and then immediately afterward from a helicopter. No significant differences were found between the means of the measurement of 20 chemical parameters for the two methods of collection. When compared to obtaining samples from a boat, collection of samples from a helicopter platform had no effect on the content of the water samples.     

Rabbit collagenase. Immunological identity of the enzymes released from cells and tissues in normal and pathological conditions.

1. The immunological cross-reactivity between rabbit collagenases from a variety of normal and pathological sources was examined. The specific antibody raised against collagenase secreted from normal rabbit synovial fibroblasts gave reactions of complete identity with collagenases secreted from fibroblasts derived from rabbit skin, and from synovium from experimentally arthritic rabbits. 2. The rabbit fibroblast collagenase was immunologically identical with collagenases obtained from the organ culture medium of normal rabbit skin, synovium, ear fibrocartilage and subchondral bone. 3. Collagenases from the culture media of normal rabbit synovium and from hyperplastic synovium of rabbits made experimentally arthritic were identical. 4. The collagenase secreted from rabbit fibroblasts gave a reaction completely identical with that of a collagenase extracted directly from a rabbit carcinoma. 5. IgG (immunoglobulin G) from a specific antiserum to rabbit fibroblast collagenase was a potent inhibitor of the collagenases obtained from the culture media of the various rabbit cells and tissues. 6. Collagenases from human synovium and from mouse macrophages and bone were neither precipitated nor inhibited by antibodies to rabbit collagenase. 7. No immunoreactive material was found in lysates of rabbit polymorphonuclear leucocyte granules with the specific antisera to rabbit fibroblast collagenase. No evidence for inactive forms of rabbit collagenase in lysates of the rabbit synovial fibroblasts could be found, either by double immunodiffusion against the specific collagenase, or by displacement of active enzyme from inhibition by the IgG.     

A PCR primer-specific to Cylindrocarpon heteronema for detection of the pathogen in apple wood

Abstract An oligonucleotide primer (ChInt) was synthesised from the variable internally transcribed spacer (ITS) 1 region of ribosomal DNA (rDNA) of Cylindrocarpon heteronema . PCR with primers ChInt and ITS4 (from a conserved sequence of the rDNA) amplified a 470-bp fragment from several isolates of C. heteronema but not from various apple wood saprophytes. Amplification of this fragment was achieved from 1–2 pg of fungal DNA. These primers amplified a fragment of the same size from DNA extracted from cankered wood but only after impurities were removed from the DNA on a Qiagen tip-5 column. Southern hybridization analysis confirmed the 470-bp fragment from C. heteronema DNA and cankered wood to be identical.     

Parastrongylus (=Angiostrongylus) cantonensis now endemic in Louisiana wildlife

Parastrongylus (=Angiostrongylus) cantonensis, a lung worm of rats, was first reported in the United States in 1987, with a probable introduction by infected rats from ships docking in New Orleans, Louisiana, during the mid-1980s. Since then, it has been reported in nonhuman primates and a boy from New Orleans, and in a horse from Picayune, Mississippi, a distance of 87 km from New Orleans. Parastrongylus cantonensis infection is herein reported in a lemur (Varencia variegata rubra) from New Iberia, Louisiana, a distance of 222 km from New Orleans, and in a wood rat (Neotomafloridanus) and in 4 opossums (Didelphis virginiana) from Baton Rouge, Louisiana, a distance of 124 km from New Orleans. The potential of a great variety of gastropods serving as intermediate hosts in Louisiana may pose a threat to wildlife as well as to domesticated animals in the areas where infected Norway rats (Rattus norvegicus) are present.     

Site of binding of IgG2b and IgG2a by mouse macrophage Fc receptors by using cyanogen bromide fragments

Cyanogen bromide fragments of murine IgG2b and IgG2a immunoglobulins were used to localize the sequences that are bound by specific IgG2b and IgG2a Fc receptors on murine macrophages. One fragment from the CH2 domain of IgG2b bound to the gamma 2b Fc receptor. Two fragments from IgG2a--one one from the CH2 domain, differing by only four amino acids from the homologous IgG2b fragment, and the other from the CH3 domain--specifically bound to the gamma 2a Fc receptor. In both a rosetting assay and a radioactive binding assay, these two fragments from IgG2a competed with intact IgG2a: however, they did not compete with each other. Rather, binding of the fragment from the CH3 domain of IgG2a augmented the binding of the fragment from the CH2 domain of IgG2a but not that of the homologous fragment from IgG2b. The binding of both IgG2a fragments was abolished by trypsin treatment of macrophages. These data suggest that 1) a sequence in the CH2 domain of IgG2b is sufficient for binding to the gamma 2b Fc receptor, 2) sequences from both the CH2 and CH3 domains of IgG2a bind to the gamma 2a Fc receptor, and 3) the binding of sequences from the CH3 domain of IgG2a may induce a conformational change in the gamma 2a Fc receptor that leads to enhanced binding of sequences from the CH2 domain.     

Cloned hst gene from normal human leukocyte DNA transforms NIH3T3 cells

The hst gene was originally identified as a transforming gene in DNAs from stomach cancers and a noncancerous portion of stomach mucosa by transfection assays using NIH3T3 cells (1,2). Subsequently, the hst gene obtained directly from leukocyte DNA of a leukemia patient was sequenced (3,4). Here, cosmid clones containing the hst gene were isolated directly from normal human leukocyte DNA and from T361-2nd-1 cells, a secondary transformant of NIH3T3 cells induced by transfection of DNA from a stomach cancer. All clones containing the hst gene from these different sources transformed NIH3T3 cells with similar efficiency. Restriction map of the hst gene from normal leukocyte DNA was identical with that from leukocyte DNA of a leukemia patient, while the hst gene from T361-2nd-1 cells was rearranged at the 168th nucleotide upstream of the TATA box.     

克隆绵羊——多莉(DOLLY)的研究进展

多莉,第一例大型克隆哺乳动物,由一只称为FinnDorset的6岁母羊乳腺体细胞的基础生命物质经细胞核转移等操作而产生。成果公布后,持怀疑观点的学者提出,提供体细胞的母羊是否本身处在妊娠状态?推测多莉是由胚胎细胞产生,并非体细胞本身克隆所致。由于6岁的母羊死于1995年,只能用其冷冻保存的乳腺组织在Hannah研究中心进行细胞群体的分析。首先,用微卫星扩增技术,以三套引物进行测定;其次,进行DNA指纹分析来断定供体体细胞起源,以确定多莉的真实性。最后证实多莉来自成年母羊乳腺的体细胞。     

Detection of Nitrosomonas spp. by polymerase chain reaction

Abstract A unique genomic DNA fragment was isolated from Nitrosomonas europaea ATCC 19718. Based on the sequence of this fragment, oligonucleotide primers for polymerase chain reaction amplification were prepared which amplify sequences of 775 and 658 bp. The predicted DNA fragments were both amplified from the genome of N. europaea and a Nitrosomonas spp. isolated from a local oxidation pond. The primers failed to amplify DNA from the genomes of the ammonia oxidiser Nitrosolobous multiformis , the nitrite oxidiser Nitrococcus mobilis as well as from the genomes of other unrelated heterotrophic bacteria. These DNA sequences could be amplified from 0.01 ng of N. europaea genomic DNA or from 100 intact cells, and it was possible to detect Nitrosomonas DNA in a DNA mixture extracted from water samples drawn from a local oxidation pond.     

Characterization and authentication of insect cell lines using RAPD markers

Random amplified polymorphic DNA (RAPD) analysis was used to characterize 11 insect cell lines, including six from lepidoptera (five species), one from diptera and four from coleoptera (one species: Leptinotarsa decemlineata). Whatever the order and even when comparing two closely related species from the same genus (Spodoptera), the DNA fingerprints are very different from one species or from one primer to the other. On the other hand, two independently isolated cell lines from the lepidopteran Phthorimaea operculella produce nearly identical profiles with only minor differences. Finally, a statistical analysis based on Nei's similarity coefficient was performed on the fingerprints of four independent cell lines from the Colorado potato beetle, L. decemlineata. Each possesses a common recognizable pattern also found in field-collected insects, while also showing a series of polymorphic markers which allow one to distinguish each cell line from the three others. RAPD fingerprinting, together with the use of appropriate statistics, thus constitutes a highly specific method both for the authentication of the species from which a cell line was developed and for the individual characterization of each cell line from a given species.     

Detecting cellulase and esterase enzyme activities encoded by novel genes present in environmental DNA libraries

A genomic DNA library was made from the alkaliphilic cellulase-producing Bacillus agaradhaerans in order to prove our technologies for gene isolation prior to using them with samples of DNA isolated directly from environmental samples. Clones expressing a cellulase activity were identified and sequenced. A new cellulase gene was identified. Genomic DNA libraries were then made from DNA isolated directly from the Kenyan soda lakes, Lake Elmenteita and Crater Lake. Crater Lake clones expressing a cellulase activity and Lake Elmenteita clones expressing a lipase/esterase activity were identified and sequenced. These were encoded by novel genes as judged by DNA sequence comparisons. Genomic DNA libraries were also made from laboratory enrichment cultures of Lake Nakuru and Lake Elmenteita samples. Selective enrichment cultures were grown in the presence of carboxymethylcellulose (CMC) and olive oil. A number of new cellulase and lipase/esterase genes were discovered in these libraries. Cellulase-positive clones from Lake Nakuru were isolated at a frequency of 1 in 15,000 from a library made from a CMC enrichment as compared to 1 in 60,000 from a minimal medium enrichment. Esterase/lipase-positive clones from Lake Elmenteita were isolated with a frequency of 1 in 30,000 from a library made from an olive-oil enrichment as compared to 1 in 100,000 from an environmental library.Communicated by K. Horikoshi     

Molecular cloning of human interleukin 2 cDNA and its expression in E. coli.

A recombinant plasmid containing human interleukin 2 (IL2) cDNA was identified in a cDNA library constructed from mRNA derived from PHA-TPA induced splenocytes. Using this cDNA as a hybridization probe, a DNA fragment containing the IL2 gene was isolated from a collection of hybrid phages derived from human genomic DNA. A unique reading frame was identified from the nucleotide sequence derived from these plasmids coding for a polypeptide of 153 amino acids and containing a putative signal sequence of 20 amino acids. A mature polypeptide starting with either Met-Ala-Pro or Met-Pro was expressed in E. coli under control of the E. coli trp promoter or using a combination of the phage lambda PL promoter and a ribosome binding site derived from phage Mu. The bacterial IL2 polypeptide had a molecular weight of 15,000 daltons and accounted for more than 10% of the total E. coli proteins in fully induced cells; it was biologically active in the T-cell specific DNA synthesis assay, even after recovery from a SDS-containing polyacrylamide gel.     

Caligus nolani n. sp. (Copepoda: Caligidae), a parasite of Patagonotothen sima (Richardson) (Teleostei: Pisces) from the Falkland Islands,and a note on Clavella bowmani,Kabata, 1963 (Copepoda: Lernaeopodidae)

Both sexes of a new species of parasitic copepod, Caligus nolani (Caligidae: Siphonostomatoida) from the skin of the nototheniid fish Patagonotothen sima from the Falkland Islands, are described. The male differs superficially from the female in having a more rounded cephalothoracic shield, a thinner genital complex and a two-segmented abdomen. C. nolani can be separated from all other species of Caligus by the shapes of the sternal furca and second antenna. Clavella bowmani Kabata, 1963 from P. sima is the first record of this species from the Falkland Islands.     

Two new British species of Halticoptera (Hymenoptera: Chalcidoidea,Pteromalidae)

The female of a new species of Halticoptera is described from a single specimen from Britain, and the male and female of a second new species are described from material from Britain and Czechoslovakia. Halticop-terina triannulata is recorded from Britain for the first time.     

Differences in molybdenum uptake by micro-organisms from the rhizosphere ofraphanus sativus L. grown in two soils of similar origin

Summary Differences have been shown in molybdenum uptake by microorganisms from the rhizosphere and soil sampled away from the roots, of the radish,Raphanus sativus L., grown in market garden soils from Napier and Hastings (New Zealand).The organisms from the rhizosphere of plants in Hastings soil concentrated up to 55 ppm of molybdenum dry weight when grown in a liquid medium made from Hastings soil extract and supplemented with carbon, phosphorus, nitrogen, sulphur and molybdenum. The growth from an inoculum of pooled fungal isolates from the rhizosphere has been shown to contain a higher concentration of molybdenum than growth from pooled bacterial or streptomycete isolates. The growth from a combined bacterial and streptomycete inoculum contained a higher concentration of molybdenum than the growth from either group alone.Organisms from the rhizosphere and soil sampled away from the roots of radishes grown in Napier soil did not contain such high concentrations of molybdenum.No significant differences in the frequency of morphological types were found in the isolates from either soil.     

N-Acetyl-β-d-hexosaminidase component A. Different forms in human tissues and fluids

1. Hexosaminidase A of human serum was resolved into two components, a minor form with properties identical with those of the single hexosaminidase A component of human liver, and a major form with significantly different properties. 2. The major serum hexosaminidase A form was eluted from a DEAE-cellulose column at a lower salt concentration than that required to elute the liver form. 3. A multiple-pass technique was used to elute the major serum enzyme A from a Sephadex G-150 column before that of liver enzyme A. 4. Clostridium perfringens neuraminidase converted the major component of serum hexosaminidase A into a form that was held less tightly by DEAE-cellulose, but the minor component of the A enzyme of serum, and the A enzyme of liver were not affected. 5. The hexosaminidase A from tears was similar to the A enzyme from serum, whereas those from several human tissues and from urine and lymph were similar to the liver form. 6. The A enzyme from serum may be derived from the A enzyme from liver by glycosylation before secretion.     

Tributyltin-resistant bacteria from estuarine and freshwater sediments.

Resistance to tributyltin (TBT) was examined in populations from TBT-polluted sediments and nonpolluted sediments from an estuary and from fresh water as well as in pure cultures isolated from those sediments. The 50% effective concentrations (EC50s) for populations were higher at a TBT-polluted freshwater site than at a site without TBT, suggesting that TBT selected for a TBT-resistant population. In contrast, EC50s were significantly lower for populations from a TBT-contaminated estuarine site than for those from a site without TBT, suggesting that other factors in addition to TBT determine whether populations become resistant. EC50s for populations from TBT-contaminated freshwater sediments were nearly 30 times higher than those for populations from TBT-contaminated estuarine sediments. We defined a TBT-resistant bacterium as one which grows on trypticase soy agar containing 8.4 microM TBT, a concentration which prevented the growth of 90% of the culturable bacteria from these sediments. The toxicity of TBT in laboratory media was influenced markedly by the composition of the medium and whether it was liquid or solid. Ten TBT-resistant isolates from estuarine sediments and 19 from freshwater sediments were identified to the genus level. Two isolates, each a Bacillus sp., may be the first gram-positive bacteria isolated from fresh water in the presence of a high concentration of TBT. There was a high incidence of resistance to heavy metals: metal resistance indices were 0.76 for estuarine isolates and 0.68 for freshwater isolates.(ABSTRACT TRUNCATED AT 250 WORDS)     

A new approach for study of structural and functional properties of proteins with unknown functions

Selected proteins were produced in Escherichia coli bacterial expression system--three proteins from extremophil bacteria: a putative monooxygenase from Deinococcus radiodurans, a putative nucleotidyltransferase from Thermotoga maritima, a putative oxidoreductase from Exiguobacterium sibiricum; and a shaperon from Homo sapiens DJ-1. The protocol of isolation & purification of recombinant proteins were developed that allowed to obtain expression products with the purity of no less than 96%. Conditions for the crystallization have been selected that allowed a stable growth of crystals. Preliminary x-ray experiments were conducted in order to confirm the quality of produced crystals; the resolution of obtained structural data was from 1.2 to 1.8 angstrom.     

Genetic consequences of irradiation in a scots pine <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L. population

The genetic consequences of irradiation were studied in a Scots pine population from a region contaminated as a result of the Chernobyl meltdown. Mutations of isozyme loci were not detected in seeds collected from trees of the first post-meltdown generation in 2004. The frequency of cells with chromosome aberrations in the root meristem of seedlings grown from the seeds did not differ from the control level. A deviation from the expected ratio 1: 1 was observed for some isozyme alleles in endosperms of seeds obtained from heterozygous trees.     

Chemical composition and oxidative status of tissues from Iberian pigs as affected by diets: extensive feeding v. oleic acid- and tocopherol-enriched mixed diets

The present work was intended to analyse the chemical composition and oxidative stability of the muscle biceps femoris and adipose tissues from Iberian pigs fed different finishing diets: free-range feeding on grass and acorns in a 'Montanera' traditional system (MON), fed in confinement with a mixed diet containing high-oleic sunflower oil (115 g/kg of diet) and supplemented with 250 mg/kg α-tocopherol (HOVE), and fed in confinement with a tocopherol-non-supplemented control mixed diet (CON). Muscles from MON pigs contained significantly (P < 0.05) higher amounts of intramuscular fat than those from HOVE and CON pigs. Muscles from MON and HOVE pigs had significantly higher levels of α-tocopherol than muscles from CON pigs whereas free-range feeding provided significantly higher levels of γ-tocopherol to muscles from MON pigs than the experimental diets did to CON and HOVE pigs. Adipose tissues from MON and HOVE pigs contained significantly lower proportions of saturated fatty acids and significantly higher levels of oleic acid and monounsaturated fatty acids than those from CON pigs. Tissues from MON pigs contained significantly smaller levels of polyunsaturated fatty acids than those from CON and HOVE pigs. To a higher extent, feeding background affected the fatty acid composition of polar lipids from the muscle biceps femoris than that of neutral lipids. Tissues from MON pigs contained significantly smaller ω-6/ω-3 values than those from pigs fed mixed diets. Compared to tissues from CON pigs, those from MON and HOVE pigs exhibited a higher oxidative stability as a likely result of a most favourable fatty acid composition and the presence of higher tocopherol levels.     

A note on the interpretation of perseveration in discrimination

The effect of one judgment upon the next judgment in a discrimination situation is considered to be the result of two types of perseveration. One arises from the judgment itself. The other results from a persistence, from one trial to the next, of a transient bias. It is shown that the resulting perseveration can then be a function of the difficulty of the first of the pair of choices. Expressions are derived from which the extent of each effect can be measured from observed proportions of responses.