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1.
Taenia tapeworms of Finnish and Swedish wolves (Canis lupus) and Finnish brown bears (Ursus arctos), and muscle cysticerci of Svalbard reindeer (Rangifer tarandus platyrhynchus), Alaskan Grant's caribou (Rangifer tarandus granti) and Alaskan moose (Alces americanus) were identified on the basis of the nucleotide sequence of a 396 bp region of the mitochondrial cytochrome c oxidase subunit 1 gene. Two species were found from wolves: Taenia hydatigena and Taenia krabbei. The cysticerci of reindeer, caribou and one moose also represented T. krabbei. Most of the cysticercal specimens from Alaskan moose, however, belonged to an unknown T. krabbei-like species, which had been reported previously from Eurasian elks (Alces alces) from Finland. Strobilate stages from two bears belonged to this species as well. The present results suggest that this novel Taenia sp. has a Holarctic distribution and uses Alces spp. as intermediate and ursids as final hosts.  相似文献   

2.
Among strains isolated from herbal drugs in a mycological survey conducted in 1977–1980, five noteworthy species of pyrenomycetous ascomycetes are described and illustrated:Gelasinospora mirabilis var.gigaspora var. nov., isolated from Taraxaci Herba (Japanese name, Hokoei);Lophotrichus ampullus, isolated from Trichosanthis Radix (Japanese name, Karokon);L. bartlettii, isolated from Chamomillae Flos (Japanese name, Kamitsure);Sordaria conoidea, isolated from Plantaginis Semen (Japanese name, Shazenshi); andThielavia subthermophila, isolated from wood ofAbies webbiana, Plantaginis Semen and Plantaginis Herba (Japanese names, Shazenshi and Shazenso).  相似文献   

3.
Temporins are small antimicrobial peptides isolated from North American and Eurasian ranid frogs that are particularly active against Gram-positive bacteria. To date, no temporins have been characterized from North African frog species. We isolated three novel members of the temporin family, named temporin-1Sa (FLSGIVGMLGKLF(amide)), -1Sb (FLPIVTNLLSGLL(amide)), and -1Sc (FLSHIAGFLSNLF(amide)), from the skin of the Sahara frog Pelophylax (Rana) saharica originating from Tunisia. These temporins were identified by a combined mass spectrometry/molecular cloning approach. Temporin-1Sa was found to be highly active against Gram-positive and Gram-negative bacteria, yeasts and fungi (MIC=2-30muM). To our knowledge, this is the first 13-residue member of the temporin family with a net charge of +2 that shows such broad-spectrum activity with particularly high potency on the clinically relevant Gram-negative strains, Escherichia coli (MIC=10muM) and Pseudomonas aeruginosa (MIC=31muM). Moreover, temporin-1Sa displays significant antiparasitic activity (IC(50) approximately 20muM) against the promastigote and amastigote stages of Leishmania infantum.  相似文献   

4.
From cultures of human umbilical vein endothelial cells incubated with3H-glucosamine or35S-sulphate, we have purified three heparan sulphate proteoglycans: 1) a low density (1.31 g/ml) proteoglycan from the cell extract, 2) a low density proteoglycan from the medium, and 3) a high density (>1.4 g/ml) proteoglycan from the medium. The disaccharide composition of heparan sulphate chains from the low density proteoglycan of the medium was examined, using specific chemical and enzymic degradations followed by gel chromatography and strong anion exchange HPLC. Chains released from each of the different proteoglycan populations were then compared by gel chromatography and gradient polyacrylamide gel electrophoresis before and after various specific degradations. The results indicate that heparan sulphate from human endothelial cells are large polymers (MW>50,000) of low overall sulphation (32–35%N-sulphated glucosamine and an N/O-linked sulphate ratio of 2.0) with rare and solitary heparin-like disaccharides. Heparan sulphate from the different proteoglycan populations appeared to have similar structure except that chains from the high density fraction were larger polymers.Abbreviations HSPG heparan sulphate proteoglycan - DSPG dermatan sulphate proteoglycan - GlcNAc(6S) N-acetylglucosamine 6-sulphate - GlcNAc6R glucosamine with either-OH or-OSO3 at C-6 - GlcNR glucosamine with either-SO3 or-COCH3 as N-substituent - GlcNSO3 N-sulphated glucosamine - GlcNSO3(3S) N-sulphated glucosamine 3-sulphate - GlcA d-glucuronic acid - IdoA l-iduronic acid - IdoA(2S) iduronic acid 2-sulphate - HexA hexuronic acid - DHexA hexuronic acid with a 4,5-double bond - Xyl xylose - SAX strong anion exchange - d.p. degree of polymerization (a disaccharide has d.p.=1 etc) - AUFS absorbance units full scale The codes used for proteoglycans denote in turn: C 2, low-density (1.35–1.28 g/ml) HSPG from the cell extract; M 1a, high density (>1.4 g/ml) HSPG fraction from the spent medium; M 2a, low-density (1.31 g/ml) HSPG from the spent medium [6].  相似文献   

5.
6.
For use in differential diagnostics of typhoid fever, samples of the capsular polysaccharide from Salmonella enterica serovar Typhi (usually named Vi-antigen) were isolated and characterized by physicochemical and serological methods. It was shown that only the sample of Vi-antigen with the minimal (0.57%) admixture of the corresponding lipopolysaccharide (LPS) from S. typhi retained a high serological activity in the tests with monoreceptor anti-Vi sera. However, it exhibited a substantially weaker reaction with sera from normal donors and patients with acute nontyphoid salmonelloses, than Vi-antigen preparations with a higher (0.8–1.2%) LPS content. The chromatographically pure Vi-antigen was further purified by triple reprecipitation with hexadecyltrimethylammonium bromide. The content of the LPS admixture in the resulting Vi-antigen samples was determined quantitatively by GC. A high purification level of the Vi-antigen from the LPS admixture allows us to hope that this preparation could serve as a basic component of the test system for the diagnostics of typhoid fever.  相似文献   

7.
O-Linked glycans were isolated from human skim milk mucins or mucin-derived high-molecular weight glycopeptides and fractionated by anion exchange chromatography into neutral and acidic alditols. Major oligosaccharides contained in the acidic fraction were purified by high performance liquid chromatography and structurally characterized by a combination of fast atom bombardment mass spectrometry, methylation analysis and 500 MHz 1H-nuclear magnetic resonance spectroscopy. The structural aspects exhibited by these major species in the acidic fraction resemble those established previously for the neutral oligosaccharides from human skim milk mucins: 1) the size of the alditols varies from tri- to decasaccharides, 2) the core structure is of the ubiquitous type 2, 3) the backbone sequences are of the poly-N-acetyllactosamine type with a particular preponderance of linearly extended GlcNAc beta(1-3)Gal (major) or GlcNAc beta(1-6)Gal units (minor).  相似文献   

8.
Anthocyanins from tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton and Montmorency; sweet cherries, Prunus avium L. (Rosaceae); bilberries, Vaccinum myrtillus L. (Ericaceae); blackberries, Rubus sp. (Rosaceae); blueberries var. Jersey, Vaccinium corymbosum L. (Ericaceae); cranberries var. Early Black, Vaccinium macrocarpon Ait. (Ericaceae); elderberries, Sambucus canadensis (Caprifoliaceae); raspberries, Rubus idaeus (Rosaceae); and strawberries var. Honeoye, Fragaria x ananassa Duch. (Rosaceae), were investigated for cyclooxygenase inhibitory and antioxidant activities. The presence and levels of cyanidin-3-glucosylrutinoside 1 and cyanidin-3-rutinoside 2 were determined in the fruits using HPLC. The antioxidant activity of anthocyanins from cherries was comparable to the commercial antioxidants, tert-butylhydroquinone, butylated hydroxytoluene and butylated hydroxyanisole, and superior to vitamin E, at a test concentration of 125 microg/ml. Anthocyanins from raspberries and sweet cherries demonstrated 45% and 47% cyclooxygenase-I and cyclooxygenase-II inhibitory activities, respectively, when assayed at 125 microg/ml. The cyclooxygenase inhibitory activities of anthocyanins from these fruits were comparable to those of ibuprofen and naproxen at 10 microM concentrations. Anthocyanins 1 and 2 are present in both cherries and raspberry. The yields of pure anthocyanins 1 and 2 in 100 g Balaton and Montmorency tart cherries, sweet cherries and raspberries were 21, 16.5; 11, 5; 4.95, 21; and 4.65, 13.5 mg, respectively. Fresh blackberries and strawberries contained only anthocyanin 2 in yields of 24 and 22.5 mg/100 g, respectively. Anthocyanins 1 and 2 were not found in bilberries, blueberries, cranberries or elderberries.  相似文献   

9.
Genealogical pedigrees were collected from 976 farming couples who lived in a canton of central France in the XIXth and XXth century. Several methods (genealogical, isonymic and probability of origin of genes) were used to appraise the evolution of the biological structure of this population, which has gone through two phases. The first phase from 1800 to the World War I, shows gene flows between the farming population of the canton and those of neighbouring rural districts which are linked to an increase in consanguineous marriages. The second phase, from 1920 onwards, shows important gene flow from distant areas. This trend implies a decrease in consanguineous marriages.  相似文献   

10.
Campylobacter,salmonella and chlamydia in free-living birds of Croatia   总被引:2,自引:0,他引:2  
Campylobacteriosis, salmonellosis and avian chlamydiosis are zoonotic diseases in which birds have been suggested to play an important role as reservoirs. We have investigated the prevalence of Campylobacter and Salmonella spp. and Chlamydophila sp. in 107 free-living birds belonging to 25 species from 13 families from Croatia in order to examine the natural infections caused by these agents. Campylobacter jejuni-like organisms were isolated from 2 of 107 free-living bird species examined (1.9%). Salmonella was isolated from 8 fresh fecal specimens from free-living bird species (7.4%). These isolates were identified as S. typhimurium in 4 (3.7%), and S. enteriditis in 4 (3.7%) free-living birds. These samples originated from feral pigeons (Columba livia domesticus; n=14; 28.6%), rook (Corvus frugilegus; n=13; 15.4%), buzzard (Buteo buteo; n=12; 16.7%), black-headed gull (Larus ridibundus; n=8; 12.5%) and tawny owl (Strix aluco; n=8; 12.5%). The presence of Chlamydophila sp. was not detected in the free-living birds examined during this study. Epidemiological aspects and possible significance of the examined birds as a source of infections for domestic animals and humans are discussed.  相似文献   

11.
Two human urinary metabolites of the industrial solvent N,N-dimethylformamide (DMF), N-hydroxymethyl-N-methylformamide (HMMF) and N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC), were assayed using a new analytical method (gas chromatography and thermionic sensitive detection). Clean-up of urine samples includes a liquid–liquid extraction step followed by a solid-phase extraction step to separate HMMF and AMCC from other urine components. During clean-up, AMCC is converted into ethyl-N-methylcarbamate (EMC), and during gas chromatography, HMMF is degraded in the injector to N-methylformamide (NMF). All the validation data necessary for a quantitative procedure are given. The method was applied to urine samples from workers exposed to DMF and from the general population. The results were confirmed by mass spectrometric determination. For this purpose a further liquid–liquid extraction step was introduced in the clean-up procedure. Background levels of AMCC in the general population were identified.  相似文献   

12.
Samples of dying branches from 121 trees of Quercus pubescens, Q. cerris, and Q. petraea were taken from 102 sites in Seslerio autumnalis-Quercetum petraeae and Ostryo-Quercetum pubescentis forests. After nine months’ rearing in eclectors, branches were cut to 20-cm sections, and signs of infestation as well as larvae and adult insects were noted. We analysed 395 sections of branches from Q. pubescens, 125 sections from Q. cerris, and 85 sections from Q. petraea. We found 44 adult insects: 45% were from the Cerambycidae family (Callimus angulatus ssp. angulatus, Poecilium alni, and Exocentrus adspersus), 18% were from the Scolytinae subfamily (Scolytus intricatus, Xyleborus dispar), 4% from the Buprestidae family (Coraebus florentinus), 4.5% from the Cleridae family (Tilloidea unifasciata), and 28.5% from other families. In addition, 145 larvae were found: 50% from the Cerambycidae family, 39% from the Buprestidae family, 4% from the Scolytinae subfamily, and 7% from other families. Significant difference in the abundance of adult insects and larvae with regard to the diameter of branch sections and the host species were found. 78% of dying branches showed signs of infestation. Species of the Buprestidae, Scolytinae, and Cerambycidae represent important factors in the decline in oak vitality in the lower Karst region of Slovenia.  相似文献   

13.
The phylogeny of Old World monkeys has remained unresolved in part because of a lack of resolution in the Cercopithecinae. Competing morphological hypotheses have had Allen's swamp monkey (Allenopithecus nigroviridis) and the talapoins (Miopithecus spp.) as basal branches of either the tribe Cercopithecini or the tribe Papionini. Previous molecular analyses have not adequately addressed the issue. To better understand the evolutionary history of these primates, we sequenced and subjected to phylogenetic analysis 3.1 kb of 2 loci (TSPY and SRY) from the non-recombining portion of the Y-chromosome. Individuals from the genera Allenopithecus, Miopithecus, Erythrocebus, Chlorocebus, and Cercopithecus were surveyed and their sequences compared with those previously published for the Papionini and Colobinae. The results suggest Allenopithecus and Miopithecus are more closely related to the Cercopithecini than Papionini. Our data also support the hypothesis that within the Cercopithecini, Erythrocebus and Chlorocebus share a close evolutionary relationship, distinct from the other members of the tribe.  相似文献   

14.
The purpose of this study was to isolate fungi from the quarter milk of cow udders from several dairy herds and to identify the different genera and species involved in mastitis. A total of 2078 milk samples from normal, clinical and subclinical mastitis quarters from 22 dairy herds of 16 districts in the State of São Paulo, Brazil was utilized in this survey. Two hundred and fifty one (12.07%) fungi were isolated from the samples. Two hundred and eight of these (82.86%) were yeasts and 30 (11.95%) were moulds. The fungi were isolated in pure culture (24.77%) or in cultures mixed with bacteria (72.22%). The yeasts isolated were:Cryptococcus spp. (71 strains),Rhodotorula spp. (40),Candida spp. (68),Trichosporon cutaneum (21),Aureobasidium pullulans (7), andPichia ohmeri (1). Moulds classified in following genera were also isolated:Aspergillus (3),Penicillium (3),Alternaria (3),Phoma (3),Epicoccum (2), andGeotrichum (16).  相似文献   

15.
Amplified ribosomal DNA restriction enzyme analysis (ARDRA), pulsed field gel electrophoresis (PFGE) and ribotyping were used to differentiate among 24 strains of Brevibacterium linens, Brevibacterium casei and Brevibacterium epidermidis obtained from type culture collections or isolated from various smear ripened cheeses. ARDRA was applied to the 16S rDNA. B. linens was shown to be a quite heterogenic group with 2 to at least 4 copies of rrn operons per strain with aberrant nucleotide sequences. AccI gave genus specific restriction patterns and was used to separate Brevibacterium from Corynebacterium species. The expected species specificity of TaqI applied to B. linens type culture strains, but not to all strains isolated from cheese. By AvaI restriction, B. casei and B. linens were differentiated from B. epidermidis and the orange pigmented Arthrobacter casei, a new species of coryneform bacteria; by XmnI restriction, B. linens and B. epidermidis were differentiated from B. casei. One of 4 B. linens genotypes could not be distinguished from B. casei by this method. Here, the typical orange B. linens pigments were used for classification, which was confirmed by partial sequencing of the 16S rDNA.  相似文献   

16.
Summary The effects of temperature, photoperiod, phytochrome photoreversion and the response to a R/FR ratio gradient were investigated in seeds of four species from two contrasting tropical habitats; two species from a rain forest (Cecropia obtusifolia and Piper umbellatum) and two from a high altitude lava field covered by low vegetation (Buddleja cordata and Chenopodium ambrosioides). In the rain forest seed species the photoblastic response seems to be adapted to light quality changes due to canopy destruction, on the other hand, the lava field seed species seem to be adapted to instantaneous light stimulus such as would be produced by the sudden exposure of a buried seed to the soil surface light environment.  相似文献   

17.
Leaf tissue of four representative species from a limestone-sandstone transition, together with their respective soils, were analysed for cations. The species studied comprisedLeucospermum cuneiforme (Proteaceae) from the acid sandstone,Indigofera sp. nov. (Fabaceae) from the base-rich limestone,Elytropappus rhinocerotis (Asteraceae) from the transition zone andDodonaea angustifolia (Sapindaceae) which occured on all three substrates. The sandstone substrate is low in cations, particularly K and it is suggested that the Leucospermum may supplement its K nutrition with Na. Despite growing on soils of differing cation content, Dodonaea maintained a constant leaf cation content over the three substrates.  相似文献   

18.
A skull fragment (VM-0) from Orce, Granada, Spain, dated palaeomagnetically at about 1.6 Myr, is thought by some palaeontologist to be hominid, while others maintain it is equid. If hominid, it would be by far the oldest evidence ofHomo in Europe. Immunological studies on residual albumin in this fossil were carried out independently, and with different immunological methods, at the University of California, San Francisco (radioimmunoassay), and at the University of Granada, Spain (enzyme immunoassay). Other fossils attributed to hominids also studied wereVM1960 from Venta Micena, andCV-1 from Cueva Victoria, Murcia, Spain. Undisputed equid and bovid fossils from the same deposits and dated to a similar period as the Orce skull were also analyzed. Our results showed that species-specific albumin can be detected in 1.6 Myr-old hominid, equid and bovid fossils. The albumin from the Orce skull fragment and fromVM-1960 was immunologically closer to human albumin. These findings support the contention that theVM-0 andVM-1960 are hominid and that members of the genusHomo occupied southern Spain 1.6 Myr ago.  相似文献   

19.
The urinary glycoprotein uromodulin (Tamm-Horsfall glycoprotein) exhibits a pregnancy-associated ability to inhibit antigen-specific T cell proliferation, and the activity is associated with a carbohydrate moiety [Muchmore and Decker (1985) Science 229:479–81; Hessionet al., (1987) Science 237:1479–84; Muchmore, Shifrin and Decker (1987) J Immunol 138:2547–53]. We report here that the Man6(7)GlcNAc2-R glycopeptides derived from uromodulin inhibit antigen-specific T cell proliferation by 50% at 0.2–2 M, and further studies, reported elsewhere, confirm that oligomannose glycopeptides from other sources are also inhibitory, with Man9GlcNAc2-R the most inhibitory of those tested [Muchmoreet al., J Leukocyte Biol (in press)]. In this work, we have extended the observation of pregnancy-associated inhibitory activity to a second species, and have compared the oligomannose profile of Tamm-Horsfall glycoprotein (nonpregnant) with that of uromodulin (pregnant) derived from both human and bovine sources. Surprisingly, there was a pregnancy-associated decrease in the total content of oligomannose chains due predominantly to a reduction in Man5GlcNAc2-R and Man6GlcNAc2-R. Man7GlcNAc2-R, which did not decrease with pregnancy, comprised a significantly greater proportion of the total oligomannose chains in pregnant vs. nonpregnant samples from both species (human; 34.6% vs. 25.9%: bovine; 14.4% vs. 7.2%).  相似文献   

20.
Cyanobacteria (photoautotrophic prokariota) have potential for the control of pathogenic bacteria and fungi. The effect of intra and extracellular products from cyanobacterial strains on the growth of fungi isolated from “wood blue stain,” was tested. Extracellular products were obtained by concentration and sterilization of the culture medium where cyanobacteria were grown. Cyanobacterial substances promoted or inhibited fungal growth according to the fungal and cyanobacterial strains tested. Extracellular products from Nostoc muscorum 79a and the methanolic extract from Microchaete tenera 84b biomass inhibited growth of Sphaeropsis sapinea 2157 (64.7 and 775.6%, respectively). Extracellular products of Nostoc piscinale 59 and biomass methanolic extract from N. muscorum 79a produced the highest growth promotion of Trichoderma boningii 452 (105.0%) and T. viride 993 (136.7%). Extracellular products of the heterotrophic lactic acid bacterium Streptococcus termophilus were also tested and strongly inhibited (64–92%) all the fungal strains. The tested fungi have different sensitivity to the bioactive substances present in the biomass and/or the culture medium of the studied cyanobacteria and lactic acid bacterium. N. muscorum 79a, M. tenera 84b, and S. termophilus have potential to control the wood blue stain fungi by a friendly environmental alternative.  相似文献   

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