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71.
A Mycobacterium leprae-specific gene encoding an immunologically recognized 45 kDa protein 总被引:1,自引:0,他引:1
Tobias F. Rinke de Wit Josephine E. Clark-Curtiss Feseha Abebe Arend H. J. Kolk Anneke A. M. Janson Miranda van Agterveld Jelle E. R. Thole 《Molecular microbiology》1993,10(4):829-838
By screening a Mycobacterium leprae lambda gt11 expression library with a serum from an Ethiopian lepromatous leprosy (LL) patient a clone was isolated (LL4) belonging to hybridization group III of a panel of previously isolated M. leprae clones. Members of this hybridization group encode a serologically recognized 45 kDa protein. The complete DNA sequences of the partially overlapping clones LL4 and L1 (hybridization group III) are presented and these revealed the presence of an open reading frame (ORF) predicting a protein with a molecular size of 42 448 Da. Southern hybridizations on total genomic DNA of M. Ieprae, Mycobacterium tuberculosis and eight atypical mycobacteria showed that the LL4 DNA fragment is specific for M. Ieprae DNA even under low-stringency conditions. The M. Ieprae specificity of LL4 DNA was further confirmed by the polymerase chain reaction using four different sets of primers. Western blotting analyses showed that the M. Ieprae 45 kDa protein is frequently recognized by antibodies from leprosy patients and that this recognition is specific since no antibodies could be detected in sera of tuberculosis patients. T-cell proliferation assays also demonstrated T-cell recognition by leprosy patients and healthy contacts of the M. Ieprae 45 kDa protein. The specificity of the LL4 DNA region and the 45 kDa antigen that is encoded by hybridization group III could provide unique tools for the development of M. Ieprae-specific immunological and DNA reagents. 相似文献
72.
Davide Scaccini Davide Bramuzzo Cengiz Bostancı Massimo Faccoli Isabel Martinez-Sañudo Alexey Matov Alberto Zilli Alberto Pozzebon 《Journal of Applied Entomology》2023,147(3):239-243
The Asian walnut moth, Garella musculana (Erschov, 1874) (Lepidoptera: Nolidae), is a major pest of walnut. Native to Central Asia, it was found to be invasive in 2008 in Sevastopol (Crimea) and nowadays widespread in Turkey, Bulgaria, Romania and Russia. Here, we account for the finding of G. musculana in NE Italy (Veneto region) in 2021, where adults were found in a light lamp, representing the first record of the Asian walnut moth for this country and Western Europe. Adult specimens were identified morphologically on both external characters and genitalia features. G. musculana larvae and damage were also observed on a plantation of Juglans regia L. (Fagales: Juglandaceae) located in Veneto in October 2021. A COI-barcoding analysis was performed to attain a molecular characterization of our specimens and probate our morphological identification. However, because no sequence of G. musculana was present in major gene databases and the similarity of our sequences with those attributed to Garella ruficirra (Hampson, 1905) (Lepidoptera: Nolidae) made clear that these taxa deserved further scrutiny regarding their specific distinction. Some subtle differences in the male terminalia could be found between them and their vast geographic distributions, but the strong similarity in most features calls for further morphological and genetical insights on a broad set of samples to assess whether they represent two closely related, substantially parapatric species, or a unique, geographically varying entity. Solving this issue may turn out crucial in the identification and proper management of walnut moths of the genus Garella. 相似文献
73.
Prof. Christchellyn Klegin Prof. Dr. Eduardo Miranda Ethur Bárbara Buhl Ana Caroline Giacomin Prof. Dr. Juçara Bordin Prof. Dr. Neusa Fernandes de Moura Matheus Henrique Oliveira de Sousa 《化学与生物多样性》2023,20(6):e202300253
The present study aimed to examine the phenolic content and evaluate the antimicrobial and antioxidant potential of ethanol extracts from the moss species Phyllogonium viride Brid. on the pathogenic bacteria Salmonella enterica serovar enteritidis, Staphylococcus aureus, Listeria monocytogenes and Escherichia coli, and the pathogenic fungi Candida albicans and Cryptococcus neoformans. The antimicrobial activity was determined from Minimum Inhibitory Concentration (MIC) Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC). Antioxidant activity was determined by the DPPH method. Folin-Denis reagent was used for the content of total phenolics and flavonoids and HPLC-DAD for identification of phenolic compounds. The results showed that bacteriostatic and bactericidal activities occurred at concentrations ranging from 9.76 μg/mL–78.13 μg/mL among all evaluated microorganisms. These values, considering the criteria used, suggest the P. viride extract as a potent antimicrobial. For antioxidant activity, P. viride extract was considered weak. Analysis of the phenolic content showed a wide range of compounds, with Kaempferol (0.41 mg/g) being the major compound, followed by t-cinnamic acid and caffeic acid (0.17 mg/g). Although P. viride is a species of moss not yet referenced in scientific publications of biotechnological interest, it has shown promising potential for further studies and possible application as an antimicrobial of natural origin. 相似文献
74.
75.
Ysabel Santos R. Laixier Isabel Bandin J. Lamas Alicia E. Toranzo 《Zeitschrift fur angewandte Ichthyologie》1991,7(3):160-167
The susceptibility of turbot, coho salmon, and rainbow trout to strains of Vibrio anguillarum of serotypes 01 and 02 and their extracellular products (ECP) was investigated in order to clarify the role of exotoxins in the mechanism of virulence of both serotypes. All V. anguillarum isolates were virulent for trout, salmon, and turbot. Despite the origin of the strains tested, rainbow trout was the most susceptible fish species to experimentally induced vibriosis. Coho salmon and turbot did not differ significantly in their susceptibility to V. anguillarum live cells. In contrast, the ECP from Vibrio strains of serotypes 01 and 02 exhibited similar lethal dose for turbot, salmon, and trout (ranging from 4.52 to 7.32 μg protein/g fish). Therefore, differences in susceptibility to vibriosis are not completely due to a differential sensitivity of fish to the extracellular products of Vibrio strains. The ECP from 7 of 10 V. anguillarum strains possessed vascular permeability factors, and all the extracts displayed proteolytic, hemolytic and cytotoxic activities. All the biological activities of ECP were lost after heat treatment at 80° C/10 min. 相似文献
76.
Aonio Bernao Isabel Meseguer María Victorina Aguilar María Carmen Martínez Para María José González Mu?oz 《Journal of trace elements in medicine and biology》2004,18(1):33-39
This 12-day study was conducted to evaluate the effects of three different levels of dietary chromium (100, 200, and 500 microg/day) in the form of chromium picolinate (CrPic) on growth and protein use in weaned rats. No significant effect of CrPic on body weight gain, food intake, or food conversion rate was observed. Elevated doses of CrPic seemed to increase muscle mass, either by stimulating protein anabolism by activation of insulin by chromium or by lowering protein degradation. However, these effects had no repercussions on overall growth, suggesting that any anabolic effect of chromium due to the action of insulin was probably marginal. 相似文献
77.
Isabel Figueiral 《Vegetation History and Archaeobotany》1996,5(1-2):121-129
The analysis of archaeological charcoal is used to reconstruct the wood resources in north-west Portugal from the late Bronze
Age to the Roman period. In this paper, the results obtained from 12 sites are considered, and their implications for interpreting
historical human behaviour towards the natural environment and vegetation are discussed. The results indicate a similar kind
of exploitation of the vegetation by different populations which used a similar range of wood resources. Fifty-one taxa are
identified and three main natural biotopes are distinguished, including mixed oak forest, wasteland vegetation and riparian
forest. The large number of taxa identified seems to testify to the existence of a good sampling of the woody vegetation growing
in the proximity of the settlements. Both dry and fresh wood were used, and the value and possible uses are suggested for
some of the most frequent taxa identified. 相似文献
78.
We assessed the potential for several acoustic properties ofthe advertisement calls of male gray tree frogs to affect relativemating success by relating patterns of variation in these propertiesto minimum differences required to elicit female choice. Dynamicproperties (pulse number, PN; call rate, CR; and duty cycle,DC, the ratio of call duration to call period) varied much morewithin bouts of calling than a static property (dominant frequency,DF) but nevertheless exhibited significant between male variationin three of four breeding seasons. Many multiply recorded malesconsistently produced calls with values substantially aboveor below mean values of males recorded on the same nights. Nightlyranges of variation in PN and CR were often greater than theminimum differences required to elicit female preferences inthe laboratory. In most experiments, females chose high-PN orfast-CR calls over low-PN or slow-CR alternatives, respectively,even if the preferred stimuli were farther away or 6-10 dB lowerin sound pressure level (SPL), provided that differences inPN or CR were 100%. Consistent with these results, females didnot always choose the closer of two calling males in the field.Nightly ranges of variation in DF rarely equaled the minimumdifference required to elicit SPL independent preferences. Femalespreferred a stimulus of high-PN and slow-CR over an alternativeof low-PN or fast-CR with the same acoustic on-time; in twoexperiments, females chose calls of high-PN over low-PN alternativeseven though the playback of the high-PN call was interruptedand the low-PN call was broadcast continuously. Thus, femalepreferences were not merely based on the total time of acousticstimulation. Responses of females tested twice in the same experimentsuggest that phenotypic variation in preference was limitedin our study populations. 相似文献
79.
Peter H. van der Melde Reno J. Groenestein Miranda C. D. C. de Labie Jonathan Heeney Pletro Pala Moncef Slaoui 《Journal of medical primatology》1995,24(4):271-281
Abstract: We investigated whether enumeration of lymphokine-secreting T cells can be used as a quantitative measure to determine the immunogenicity of foreign proteins in rhesus monkeys. In addition, it was assessed whether this approach can supplement and/or substitute for the well-established lymphoproliferation assay. Two candidate vaccine proteins (e.g., HIV-1 gp120 and HSV-2gD) were used as model antigens for immunization. PBMCs from immunized animals were antigenically stimulated and evaluated on their proliferative capacity and lymphokine release at the single cell level. The experiments showed a close quantitative correlation between antigen-triggered proliferative responses and the antigen-induced generation of Il-2 and IFN-gamma producing cells (pc). Il-4pc were found to appear relatively late after the initiation of antigen exposure. The data indicate that ELISPOT assays provide valuable tools for the assessment of the antigenicity of foreign proteins in vivo. 相似文献
80.
Howard J. Williams Isabel Sattler Guillermo Moyna A. Ian Scott Alois A. Bell S. Bradleigh Vinson 《Phytochemistry》1995,40(6):1633-1636
Major sesquiterpene components of oil of Texas Race Stock 810 of Gossypium hirsutum were - and β-selinene. This is the seventh cyclic terpene type found to date in this genus. Both - and β-selinene, along with aromadendrene, were found but only as minor components of extracts of several domestic cultivars of G. hirsutum. 相似文献