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991.
Jesús E. Blanco Miguel Blanco Jorge Blanco Azucena Mora Luis Balaguer Luis Cuervo Carlos Balsalobre Francisco Muoa 《Microbiology and immunology》1997,41(2):77-82
A field study was carried out with the objective of investigating the prevalence of enteropathogenic Escherichia coli (EPEC) with the eae gene in diarrhoeic rabbits. EPEC eae+ were isolated from 60 (74%) of 81 diarrhoeic rabbits sampled in 30 industrial fattening farms localized in the four provinces of Galicia (northwestern Spain). Attaching and effacing lesions were found in 44 of 50 animals processed for histology. The 111 E. coli strains identified belonged to 19 different O serogroups and 13 biotypes. However, 53 (48%) of the strains belonged to serogroup O103 and 36 (32%) showed the serobiotype O103:B14. The eae gene was significantly more frequent (100%; 47 of 47) among the highly pathogenic rhamnose-negative strains of serobiotypes O103:B6 and O103:B14 than among the E. coli strains belonging to other serobiotypes (36%; 23 of 64) (P < 0.001). In this first report about the prevalence of EPEC with the eae gene in rabbits, we conclude that the class of E. coli strains observed is a common cause of diarrhoea in Galician rabbit farms, and that highly pathogenic rhamnose-negative strains of serotype O103:K-:H2 and biotype B14 are specially predominant. 相似文献
992.
Several new bacteriophages infecting strain C3 ofCitrobacter intermedius have been isolated from fresh waters. The physicochemical properties, plaque morphology, growth characteristics, virion structure, and immunology of eight bacteriophage isolates are reported. The phages are classified into three groups according to their characteristics. 相似文献
993.
Chromosome counts of the following 30 taxa (106 populations) are given:Betonica officinalis (2n=16);Bidens frondosus (2n=48);Calamagrostis arundinacea (2n=28+0–2B);Dianthus carthusianorum subsp.latifolius (2n=30);Festuca gigantea (2n=42, 42+2B);Hypericum perforatum (2n=32);Koeleria macrantha (2n=28);Kohlrauschia prolifera (2n=30);Lilium martagon (2n=24+0–2B);Melica ciliata (2n=18);Poa remota (2n=14);Ranunculus polyanthemos (2n=16);R. sardous subsp.sardous (2n=16);Roegneria canina (2n=28+0–1B);Rudbeckia laciniata (2n=76);Scabiosa canescens (2n=16);Serratula tinctoria (2n=22);Seseli elatum subsp.heterophyllum var.beckii (2n=18);S. hippomarathrum (2n=20);Thlaspicaerulescens caerulescens subsp.tatrense (2n=14);Trifolium alpestre (2n=16);T. avense (2n=14);T. medium (2n=79, 80+0–2B, 82);T. rubens (2n=16);Veronica officinalis subsp. alpestris (2n=36);Vincetoxicum hirundinaria (2n=22);Vulpia bromoides (2n=14);Zerna benekenii (2n=28)Z. monoclada (2n=28+0–8B);Z. ramosa (2n=42). Remarks on taxonomy, nomenclature and chorology for some of these taxa are given. 相似文献
994.
Jacques Dornand Jean-Claude Bonnafous Jean Favero Agnés Gartner Jean-Claude Mani 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1984,804(4):398-403
It is now well established that human lymphoblastoid cell lines showing immaturity characters display ecto-5′-nucleotidase activities lower than normal levels. A recent paper (Sun, A.S., Holland, J.F. and Ohnuma, T. (1983) Biochim. Biophys. Acta 762, 577–584) mentioned that this phenomenon resulted from the presence of a 5′-nucleotidase inhibitor in these cell lines. We demonstrate here that the use of 5′-[3H]AMP as a substrate, and inadequate analysis of the products formed, led them to a misinterpretation. [3H]Adenosine derived from 5′-[3H]AMP hydrolysis was further transformed into [3H]inosine by the adenosine deaminase activity of the leukemic cell lines tested; [3H]inosine was precipitated with the excess substrate and was not taken into account in the ecto-5′-nucleotidase determination, which led the authors to confuse this adenosine deaminase activity with a 5′-nucleotidase inhibitor. We did not observe 5′-nucleotidase inhibition by leukemic cell cytosol when convenient assay methods were used and showed that the presence of such an inhibitor remains to be established. 相似文献
995.
Ethylene production and respiration by Granny Smith apples were inhibited by treatment with 20% CO2 for 2 hours. A similar effect was observed in tissue slices when treated at either 0 or 25°C.
The inhibition continued even after an extended aeration period. There is also an inhibition of ethylene emission in tissue slices incubated with exogenous 1-aminocyclopropane-1-carboxylic acid (ACC).
In general, CO2 treatment increased the ACC content of the tissue. These observations are consistent with the idea the action of CO2 is directed toward the enzyme system responsible for the conversion of ACC into ethylene.
相似文献996.
Fernando A. de Freitas José Andrés Yunes Marcio J. da Silva Paulo Arruda Adilson Leite 《Molecular genetics and genomics : MGG》1994,245(2):177-186
A genomic clone encoding the γ-kafirin gene from sorghum was isolated and sequenced. A 2938 bp sequenced fragment includes an intronless open reading frame of 636 nucleotides encoding a putative polypeptide of 212 amino acids. Comparison of the deduced amino acid sequence of γ-kafirin with the published sequences of γ-prolamins of maize, and Coix revealed highly conserved domains. The N-terminal region of these proteins contains the conserved hexapeptide PPPVHL, which is repeated eight times in γ-zein, four times in γ-kafirin and three times in γ-coixin. The number of PPPVHL repeats accounts predominantly for the differences in the molecular weights of γ-prolamins. Several putative regulatory sequences common to the γ-kafirin and γ-zein genes were identified in both the 5′ and the 3′ flanking regions. Putative GCN4-like regulatory sequences were found at positions ?192 and ?476 in the 5′ flanking region of γ-kafirin. In the 3′ noncoding region, three putative polyadenylation signals, two AATAAT and one AATGAA, were found at positions + 658, + 716, and + 785, respectively. In order to investigate the role of the putative GCN4-like motifs and other possible cis-acting element(s) of the γ-kafirin promoter, a series of deleted and chimeric promoter constructs were introduced into maize, Coix and sorghum tissues by particle bombardment. Histochemical analysis of β-glucuronidase (GUS) activity in different tissues indicated that the element(s) responsible for tissue specificity is probably located in the 285-bp proximal region of the promoter, while the remaining promoter sequence seems to carry the element(s) responsible for the quantitative response. 相似文献
997.
Gemma Fabris M. Pilar Marco Francisco Camps 《Archives of insect biochemistry and physiology》1994,27(2):77-87
The control of Spodoptera littoralis sex pheromone biosynthesis has been investigated with synthetic pheromone biosynthesis activating neuropeptide (PBAN) and different labeled tracers using an in vitro isolated gland system. Responsiveness of the glands to PBAN stimulation was impaired by careless tissue manipulation. The fact that PBAN is active in the isolated gland system suggests that this might be a target organ for this peptide in S. littoralis. As reported previously with Br-SOG extracts and intact females, label incorporation into the pheromone increased in glands treated with PBAN from all the precursors tested. However, the formation of labeled intermediates from d5E11–14:Acid also occurred in glands incubated in the absence of the peptide, but the amounts of d5Z9, E11–14:Acid were lower in PBAN treated glands than in controls. These results indicate that PBAN controls pheromone biosynthesis in S. littoralis by regulating the reduction of acyl moieties. © 1994 Wiley-Liss, Inc. 相似文献
998.
A gamete recognition mechanism in Antithamnion sparsum Tokidais proposed based on experiments using various lectins and carbohydrates.Spermatial binding to trichogynes is inhibited by pre-incubationof spermatia with concanavalin A (ConA) and/or L-fucose, whiletrichogyne receptors are blocked by the complementary carbohydrate-methyl D-mannose and/or the lectin Ulex europaeus agglutinin(UeA1). Binding inhibition (4050%) was observed with1050 mM carbohydrates and 2550 µg ml-1 lectins.The inhibitory effects of ConA and UeA1 is partially reversed(to 8090% of controls) by addition of -methyl D-mannoseand L-fucose, respectively. Lectin binding to spermatial surfaceswas visualized by Fluorescein isothiocyanate (FITC) conjugatedConA, whereas carbohydrate receptors along the trichogyne andspermatium were localized with -mannosylated-FITC-albumin andL-fucosylated-FITC-albumin, respectively. These results suggestthat gamete recognition in Antithamnion sparsum is mediatedby a double-docking recognition system consisting of spermatiapossessing surface L-fucose receptors and -methyl D-mannosemoiety, and trichogynes possessing the complementary receptors. (Received December 5, 1995; Accepted April 22, 1996) 相似文献
999.
Janire De-La-Torre Guillermo Quindós Cristina Marcos-Arias Xabier Marichalar-Mendia María Luisa Gainza Elena Eraso Amelia Acha-Sagredo José Manuel Aguirre-Urizar 《Revista iberoamericana de micología》2018,35(3):134-139
Background
Candida can be implicated in the pathology of chronic periodontitis.Aims
To analyze the oral Candida carriage in patients suffering from chronic periodontitis (CP) and its correlation with the severity of this condition.Methods
Microbiological samples were taken from 155 patients using the oral rinse (OR) technique and by using paper points in the periodontal pockets (GPP). These patients were divided into 3 groups: 89 patients without CP (control), 47 with moderate CP, and 19 with severe CP. Samples were cultured in a Candida chromogenic agar for Candida. Species were identified by microbiological and molecular methods.Results
Candida was isolated in the OR of 45 (50.6%), 21 (44.7%), and 11 (57.9%) patients, respectively, and in the GPP of 32 (36%), 14 (29.2%), and 10 (42.6%) patients from the control, moderate CP and severe CP groups, respectively. Candida was isolated more frequently and in a greater burden in OR than in GPP (p < 0.01). Candida albicans was the most prevalent species. GPP of patients with CP had poor fungal biodiversity (p < 0.01).Conclusions
Colonization by Candida was present in the samples of patients without CP, and with both moderate and severe CP. Nonetheless, patients with severe CP had a higher rate of Candida colonization, especially by C. albicans. 相似文献1000.
Priya A. Debisarun Katharina L. Gssling Ozlem Bulut Gizem Kilic Martijn Zoodsma Zhaoli Liu Marina Oldenburg Nadine Rüchel Bowen Zhang Cheng-Jian Xu Patrick Struycken Valerie A. C. M. Koeken Jorge Domínguez-Andrs Simone J. C. F. M. Moorlag Esther Taks Philipp N. Ostermann Lisa Müller Heiner Schaal Ortwin Adams Arndt Borkhardt Jaap ten Oever Reinout van Crevel Yang Li Mihai G. Netea 《PLoS pathogens》2021,17(10)