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.     

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.     

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.     

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.     

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。     

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.     

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.     

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.     

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.     

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.     

Aeolid opisthobranch molluscs (Glaucidae) from the Indian Ocean and the south-west Pacific

Eight aeolid opisthobranch molluscs of the subfamilies Facelininae, Favorininae, and Herviellinae are reported from Tanzanian waters, and two species from Northwestern India. New records from Queensland, Australia greatly extend the range of two species reported from Tanzania. Phidiana militaris (Alder & Hancock) and P. indica (Bergh) are shown to be distinct and a species from New Zealand, originally identified as P. militaris , is shown to be new. P. bourailli (Risbec), previously reported only from New Caledonia, is described from Tanzania, as is a new species of Phidiana. Favorinus japonicus Baba is reported from Tanzania, the first published record outside Japan, a new species of Godiva is described from Tanzania and Queensland, and three new species of Sakuraeolis are described, one from India and two from Tanzania. A new species of Herviella is described from Tanzania.     

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.     

Active drag, useful mechanical power output and hydrodynamic force coefficient in different swimming strokes at maximal velocity.

By comparing the time of the same distance swum with and without an added resistance, under the assumption of an equal power output in both cases, the drag of 73 top swimmers was estimated. The active drag Fr(a.d.) at maximal swimming velocities varied considerably across strokes and individuals. In the females Fr(a.d.) ranged from 69.78 to 31.16 N in the front-crawl, from 83.04 to 37.78 N in dolphin, from 93.56 to 45.19 N in breaststroke, and from 65.51 to 37.79 N in back-stroke. In the males Fr(a.d.) ranged from 167.11 to 42.23 N in front-crawl, from 156.09 to 46.95 N in dolphin, from 176.87 to 55.61 N in breaststroke, and from 146.28 to 46.36 N in back-stroke. Also, the ratio of Fr(a.d.) to the passive drag Fr(a.d.) as determined for the analogical velocity in a tugging condition (in standard body position-front gliding) shows considerable individual variations. In the female swimmers variations in Fr(a.d.)/Fr(p.d.) ranged from 145.17 to 59.94% in front-crawl, from 192.39 to 85.57% in dolphin, from 298.03 to 124.50% in breaststroke, and from 162.87 to 85.61% in back-stroke. In the male swimmers variations in Fr(a.d.)/Fr(p.d.) ranged from 162.24 to 62.39% in front-crawl, from 191.70 to 70.38% in dolphin, from 295.57 to 102.83% in breaststroke, and from 198.82 to 74.48% in back-stroke. The main reason for such variations is found in the individual features of swimming technique and can be quantitatively estimated with the hydrodynamic force coefficient, which thus provides an adequate index of technique.     

Analysis of epidemic and sporadic strains of Listeria monocytogenes by pyrolysis mass spectrometry

Twenty-six cultures of Listeria monocytogenes , serovar 4b, including 10 from a food-borne outbreak in Switzerland and sporadic patient and food isolates from both Switzerland and the UK, were compared by pyrolysis mass spectrometry (PMS). This clustered all of the Swiss epidemic isolates with four other isolates indistinguishable from the Swiss strain by phage typing, a phage non-typable isolate from a Swiss patient not known to be part of the epidemic and two strains (both from Switzerland) of a different phage type. The eight strains excluded from the PMS-derived cluster were all either known to be unrelated to the epidemic, or of a phage type distinct from the epidemic strain, or both.     

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)     

Detection and partial characterization of a human mast cell carboxypeptidase

Using a high performance liquid chromatography assay that detects the cleavage of the C-terminal leucine from angiotensin I, we have identified a carboxypeptidase activity in mast cells from human lung and in dispersed mast cell preparations from human skin. The enzyme activity was detected in a preparation of dispersed human mast cells from lung of greater than 99% purity and was released with histamine after stimulation with goat anti-human IgE. In nine preparations of dispersed human mast cells from lung of 10 to 99% purity, net percentage of release of carboxypeptidase correlated with the release of histamine, localizing carboxypeptidase to mast cell secretory granules. The enzyme activity was also detected in preparations of dispersed human mast cells from skin and in extracts of whole skin. The inhibitor profile and m.w. of carboxypeptidase activity from preparations of dispersed mast cells from skin was similar to that from dispersed mast cells from lung. Mast cell carboxypeptidase had a m.w. on gel filtration of 30,000 to 35,000. The enzyme in crude lysates of dispersed mast cell preparations had optimal activity between pH 8.5 and 9.5 and was inhibited by potato inhibitor, which distinguished it from carboxypeptidase in cultured human foreskin keratinocytes and adult fibroblasts, and from other proteolytic mast cell enzymes. The enzyme activity was also inhibited by EDTA, o-phenanthroline, and, to a small extent, by 8-OH quinoline, but not by Captopril, soybean trypsin inhibitor, or pepstatin. These findings demonstrate that human mast cell secretory granules contain carboxypeptidase in addition to tryptase and chymase. It appears that mast cells from skin may have a higher content of carboxypeptidase than do mast cells from lung.     

Functional and structural relationship of various extradiol aromatic ring-cleavage dioxygenases of Pseudomonas origin

Abstract The extradiol ring-cleavage dioxygenases derived from seven different Pseudomonas strains were expressed in Escherichia coli and the substrate specificities were investigated for a variety of catecholic compounds. The substrate range of four 2,3-dihydroxybiphenyl dioxygenases from biphenyl-utilizing bacteria, 3-methylcatechol dioxygenase from toluene utilizing Pseudomonas putida F1, 1,2-dihydroxynaphthalene dioxygenase from a NAH7 plasmid, and catechol 2,3-dioxygenase from a TOL plasmid pWW0 were compared. Among the dioxygenases, that from Pseudomonas pseudoalcaligenes KF707 showed a very narrow substrate range. Contrary to this, the dioxygenase from pWW0 showed a relaxed substrate range. The seven extradiol dioxygenases from the various Pseudomonas strains are highly diversified in terms of substrate specificity.     

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.     

Saprophytic fungi isolated from the hair of domestic and laboratory animals with suspected dermatophytosis

Hair samples from domestic and laboratory animals with suspected dermatophytosis were examined for the presence of saprophytic fungi. A nutritionally poor base medium, developed by the author, was used in the isolation and identification of the saprophytes. Three hundred and ninety-four specimens were examined of which 246 were from dogs, 75 from cats, 30 from horses, 19 from cows, 12 from guinea pigs, 5 from rats, 2 from parakeets, 2 from chinchillas and one each from a goat, a mink and a lesser panda (Ailurus fulgens). Moulds classified in 32 genera were isolated. The commonest in order of frequency were members of the genera Penicillium, Cladosporium, Aspergillus, Mucor, Aureobasidium, Alternaria, Scopulariopsis, Trichoderma and Trichothecium. The yeasts that were isolated were not identified. Aureobasidium pullulans was isolated significantly more often (chi 2 test p less than 0.025) from the dog samples than those from cats, Cladosporium spp. in the samples from dogs than horses, Mucor spp. from the cow samples than horses, Penicillium spp. from the dog samples than those of cats or horses. Skin infections caused by any of the contaminants were not encountered.