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1.
Staphylococcus capitis subsp. ureolyticus subsp. nov. from human skin   总被引:4,自引:0,他引:4  
A new subspecies, Staphylococcus capitis subsp. ureolyticus, was isolated from human skin and is described on the basis of studies of 15 to 26 strains. DNA-DNA reassociation reactions demonstrated that these strains were closely related to Staphylococcus capitis but were significantly divergent. The strains of S. capitis subsp. ureolyticus can be distinguished from S. capitis by their positive urease activity, their ability to produce acid from maltose under aerobic conditions, their fatty acid profile, and their colony morphology. The type strain of the new subspecies is strain ATCC 49326.  相似文献   

2.
In Israel, the head louse, Pediculus capitis, developed resistance to DDT through the extensive use of this insecticide until the 1980s. In 1991, permethrin was introduced for control of DDT resistant P. capitis in Israel, leading to control failure of this pyrethroid insecticide by 1994. Pyrethroid resistance of P. capitis in Israel extends to phenothrin, which has not been used for louse control. We identified a glutathione S-transferase(GST)-based mechanism of DDT resistance in the Israeli head lice. This GST mechanism occurred before 1989, while permethrin resistance in P. capitis developed after 1994, suggesting that the main GST resistance mechanism selected by DDT use does not confer any pyrethroid cross-resistance. Esterase activity levels were equivalent in pyrethroid resistant and susceptible P. capitis field-collected in Israel, and in a susceptible strain of P. humanus, the body louse, indicating no involvement of any esterase-based mechanism in resistance. A weak monooxygenase-based permethrin metabolism resistance mechanism was the only factor identified which could account for any of the observed pyrethroid resistance in P. capitis. However, the lack of synergism of phenothrin resistance by piperonyl butoxide suggests that a non-oxidative mechanism is also present in the resistant lice. Therefore it seems probable that pyrethroid resistance in Israeli P. capitis is due to a combination of nerve insensitivity (knockdown resistance or 'kdr') and monooxygenase resistance mechanisms.  相似文献   

3.
Aims:  Histamine intoxication is probably the best known toxicological problem of food-borne disease. A histamine-producing Staphylococcus capitis strain has been isolated from a cured meat product. The aim of this study was to gain deeper insights into the genetic determinants for histamine production in Staph. capitis .
Methods and Results:  The nucleotide sequence of a 6446-bp chromosomal DNA fragment containing the hdcA gene encoding histidine decarboxylase (HDC) has been determined in Staph. capitis IFIJ12. This DNA fragment contains five complete and two partial open reading frames. Putative functions have been assigned to gene products by sequence comparison with proteins included in the databases. The hdcA gene has been expressed in Escherichia coli resulting in HDC activity. The presence of a functional promoter (P hdc ) located upstream of hdcA has been demonstrated. Insertion of the histamine biosynthetic locus in Staph. capitis seems to be associated with a noticeable genome reorganization.
Conclusions:  Among the staphylococcal species analysed in this study only Staph. capitis strains produce histamine. The hdcA gene cloned from Staph. capitis encodes a functional HDC that produce histamine from the amino acid histidine.
Significance and Impact of the Study:  The identification of the DNA region involved in histamine production in Staph. capitis will allow further work in order to avoid histamine production in foods.  相似文献   

4.
Abstract Four mouse monoclonal antibodies reacting with Coxiella burnetii lipopolysaccharide antigens were produced and used in serotyping 17 C. burnetii isolates from acute Q fever and Q fever endocarditis patients in France. Two monoclonal antibodies (1B2 and 3B6) were considered specific for the Priscilla strain, a representative of Q fever endocarditis isolates, and did not react with the Nine Mile strain, which is representative of acute Q fever isolates. Monoclonal antibodies Nos. 1B2 and 3B6 reacted with 75% (3/4) acute Q fever isolates and 85% (11/13) of endocarditis isolates from France. It is reasonable to conclude that Priscilla-like strains cause both acute Q fever and Q fever endocarditis. The hypothesis that Priscilla-like strains only are associated with Q fever endocarditis should be reconsidered.  相似文献   

5.
Tinea capitis due to Trichophyton tonsurans is currently epidemic among Japanese Judo practitioners. T. tonsurans has seven genotypes in a variable internal repeat (VIR) region of the rRNA gene. All 101 isolates obtained from Japanese Judo practitioners had the identical genotype. This suggests that a specific genotype strain occurs throughout Japan.  相似文献   

6.
Human lice (Phthiraptera: Pediculidae) from Africa, America and Europe were electrophoresed for 28 enzymes, with special interest in metabolic factors likely to be involved with insecticide resistance. Zymogram profiles of the body louse (Pediculus humanus L. from France and U.S.A.) and the head louse (P. capitis DeGeer from France, Madagascar, Mali & Senegal) were compared. Only esterase two enzymes, phosphoglucomutase (Pgm) and 3 (Est-3), showed electrophoretic variation. In our starch gel electrophoresis conditions, P. humanus showed three electromorphs of Pgm migrating anodally 6, 11 and 16 mm (designated alleles a, b, c, respectively). Of the putative Pgm alleles, b and c occurred in all samples of both species of lice, whereas allele a was found only in P. humanus lab strain from U.S.A. Esterase 3 had four electromorphs migrating 23, 26, 30 and 35 mm (designated alleles a, b, c and d). Among putative Est alleles, a was found only in P. capitis from Bamako (all 14 specimens aa homozygotes), allele d was found only in P. capitis from Dakar (39% frequency), whereas Est-3 alleles b and c showed apparently balanced polymorphism in all samples of both P. humanus and P. capitis except that from Bamako. Despite the limited amount of isoenzyme variation detected (only 2/31 polymorphic loci), divergences of Est-3 and Pgm among Pediculus populations may be relevant to their biosystematics and resistance.  相似文献   

7.
Passive protective activity of rabbit antiserum prepared by a representative capsular type II strain of Staphylococcus epidermidis in mice was absorbed out with homologous capsular type strains of S. simulans, S. cohnii, S. xylosus, S. hominis, S. capitis, S. hyicus, S. haemolyticus, and S. saprophyticus in addition to the homologous strain. The minimum amount of the strains required for absorption differed greatly, depending upon the strain. No absorption of the activity was shown with a strain of capsular type I and III of S. epidermidis, S. simulans, and S. cohnii, and a strain of capsular type III of S. hominis. These results suggest a possible capsular type specificity in the cross protection between strains of S. epidermidis and other species of coagulase-negative staphylococci.  相似文献   

8.
We characterized the serological and pathogenic properties of two Erysipelothrix rhusiopathiae isolates from human cases of infective endocarditis in Japan. One isolate was recovered from a fisherman, and was identified as serovar 3, which is known to be prevalent among fish isolates. This strain exhibited high virulence in mice but was avirulent in swine. Another was untypable, and avirulent in both mice and swine. Our results suggest that various serological and athogenical types of E. rhusiopathiae can induce human endocarditis. This is the first report to characterize the pathogenicity of E. rhusiopathiae isolates from human endocarditis.  相似文献   

9.
In swifts and hummingbirds (Apodiformes), the splenius capitis muscle displays a characteristic modification, the 'cruciform origin'. The muscle pairs arise from the second vertebra by several slips which criss-cross and interdigitate with each other, before inserting into the skull. In the course of a study on the neck muscles of the Common Swift, we paid special attention to the arrangement of these slips of the splenius capitis muscle, and noted a previously unrecognized individual modification of this muscle. In addition, we observed an incipient cruciform origin of the deep portion (slip) of the rectus capitis ventralis muscle that has not been noticed for swifts or any other avian taxon before. The development and function of these modifications of the splenius capitis and rectus capitis ventralis muscle are discussed.  相似文献   

10.
11.
目的 了解我国华东地区近18年头癣趋势及病原菌分布情况.方法 采用回顾性分析方法 对1993年1月~2010年12月在我院皮肤科门诊诊治的华东地区的头癣患者进行分析.结果 946例头癣患者,男410例,女536例;年龄20d~93岁;784例真菌培养阳性患者中,白癣473例、黑癣216例、脓癣94例、黄癣1例.主要病原菌为羊毛状小孢子菌470株、紫色毛癣菌154株、断发毛癣菌81株.其中,培养出亲人性皮肤癣菌(紫色毛癣菌32例、断发毛癣菌12例、红色毛癣菌8例)的头癣患者与各种动物有密切接触史.本研究显示头癣发病率2001年达高峰之后逐渐下降,但于2010年又出现新的上升趋势.结论 我国华东地区头癣患者中自癣发病率占首位,其主要致病菌为羊毛状小孢子菌.培养出亲人性皮肤癣菌的头癣患者与各种动物有密切接触,提示亲人性皮肤癣菌在人与动物之间有互相传染的现象.2010年新的上升趋势值得我们关注.  相似文献   

12.
J. Fisher  D.L. Levene 《CMAJ》1975,112(10):1217
A 24-year-old woman with Marfan''s syndrome and mitral regurgitation had clinical features suggestive of infective endocarditis. The causative organism was Streptococcus viridans. Initial therapy with penicillin G, in a dose that should have been bactericidal and hence curative according to the results of the initial quantitative antimicrobial studies, became inadequate. The strain of S. viridans displayed considerable variation in both growth properties and antimicrobial sensitivity during the course of therapy. In addition, a different strain of S. viridans was cultured 1 month after treatment had begun. It is therefore important to repeat cultures and antimicrobial sensitivity testing during treatment of infective endocarditis.  相似文献   

13.
Callahan JE  Munro CL  Kitten T 《PloS one》2011,6(10):e26403
Streptococcus sanguinis is an important component of dental plaque and a leading cause of infective endocarditis. Genetic competence in S. sanguinis requires a quorum sensing system encoded by the early comCDE genes, as well as late genes controlled by the alternative sigma factor, ComX. Previous studies of Streptococcus pneumoniae and Streptococcus mutans have identified functions for the >100-gene com regulon in addition to DNA uptake, including virulence. We investigated this possibility in S. sanguinis. Strains deleted for the comCDE or comX master regulatory genes were created. Using a rabbit endocarditis model in conjunction with a variety of virulence assays, we determined that both mutants possessed infectivity equivalent to that of a virulent control strain, and that measures of disease were similar in rabbits infected with each strain. These results suggest that the com regulon is not required for S. sanguinis infective endocarditis virulence in this model. We propose that the different roles of the S. sanguinis, S. pneumoniae, and S. mutans com regulons in virulence can be understood in relation to the pathogenic mechanisms employed by each species.  相似文献   

14.
Yu J  Chen W  Wan Z  Li RY 《Mycopathologia》2004,158(1):49-52
Tinea capitis is rare in adults. We report a case of adult tinea capitis due to Trichophyton violaceum in China. The female patient was immunosuppressed with prednisone due to the underlying disease of vulgaris pemphigus and was treated successfully with terbinafine. We also reviewed published cases of adult tinea capitis in China and compared these data with the characteristics of published cases in other regions in the world.  相似文献   

15.
The head louse, Pediculus capitis De Geer (Phthiraptera: Pediculidae) has developed resistance to organochlorines, the organophosphate malathion and to pyrethroids in the U.K. Therefore, headlice from Bristol school children were bioassayed against two new insecticides, fipronil and imidacloprid. Pediculus capitis was fully susceptible to imidacloprid, but it required a relatively high dose and acted slowly. Fipronil acted faster at lower dose, but seemed to be affected by cross-resistance in a small proportion of P. capitis.  相似文献   

16.
The morphometry, histochemistry, and biomechanical relationships of rectus capitis muscles were examined in adult cats. This family of muscles contained six members on the dorsal, ventral, and lateral aspects of the upper cervical vertebral column. Three dorsal muscles (rectus capitis posterior major, medius, and minor) formed a layered complex spanning from C1 and C2 to the skull. Rectus capitis posterior major was composed predominantly of fast fibers, but the other two deeper muscles contained progressively higher proportions of slow fibers. One ventral muscle, rectus capitis anterior major, was architecturally complex. It originated from several cervical vertebrae and appeared to be divided into two different heads. In contrast, rectus capitis anterior minor and rectus capitis lateralis were short, parallel-fibered muscles spanning between the skull and C1. The ventral muscles all had nonuniform distributions of muscle-fiber types in which fast fibers predominated. Dorsal and ventral muscle groupings usually had cross-sectional areas of 0.5 cm2 or more, reflecting a potential capacity to generate maximal tetanic force in excess of 9 N. Biomechanical analyses suggested that one muscle, rectus capitis lateralis, had its largest moment in lateral flexion, whereas the other muscles had large, posturally dependent moment arms appropriate for actions in flexion-extension. The observation that most rectus muscles have relatively large cross-sectional areas and high fast-fiber proportions suggests that the muscles may have important phasic as well as postural roles during head movement. © 1993 Wiley-Liss, Inc.  相似文献   

17.
Streptococcus mutans is the major pathogen of dental caries and occasionally causes infective endocarditis. Here we report the complete genome sequence of serotype k S. mutans strain LJ23, which was recently isolated from the oral cavity of a Japanese patient.  相似文献   

18.
Streptococcus mutans belongs to the viridans group of oral streptococci, which is the leading cause of endocarditis in humans. The LraI family of lipoproteins in viridans group streptococci and other bacteria have been shown to function as virulence factors, adhesins, or ABC-type metal transporters. We previously reported the identification of the S. mutans LraI operon, sloABCR, which encodes components of a putative metal uptake system composed of SloA, an ATP-binding protein, SloB, an integral membrane protein, and SloC, a solute-binding lipoprotein, as well as a metal-dependent regulator, SloR. We report here the functional analysis of this operon. By Western blotting, addition of Mn to the growth medium repressed SloC expression in a wild-type strain but not in a sloR mutant. Other metals tested had little effect. Cells were also tested for aerobic growth in media stripped of metals then reconstituted with Mg and either Mn or Fe. Fe at 10 micro M supported growth of the wild-type strain but not of a sloA or sloC mutant. Mn at 0.1 micro M supported growth of the wild-type strain and sloR mutant but not of sloA or sloC mutants. The combined results suggest that the SloABC proteins transport both metals, although the SloR protein represses this system only in response to Mn. These conclusions are supported by (55)Fe uptake studies with Mn as a competitor. Finally, a sloA mutant demonstrated loss of virulence in a rat model of endocarditis, suggesting that metal transport is required for endocarditis pathogenesis.  相似文献   

19.
We evaluated the incidence of dermatophytes isolated at our hospital in the years of 1997 to 2000 and correlated it with anatomical site and age. Trichophyton rubrum was the predominant species in all anatomical sites, excluding scalp, followed by Microsporum canis, the leading agent of tinea capitis. All dermatophytosis, except tinea capitis by M. canis and Trichophyton schoenleinnii appeared mainly in adult patients. Our results revealed no substantial differences to other portuguese studies regarding the major agents. We found a relatively high incidence of T. schoenleinnii as second tinea capitis agent.  相似文献   

20.
Yu J  Wan Z  Chen W  Wang W  Li R 《Mycopathologia》2004,157(1):37-41
Tinea capitis is a dermatophyte infection of the scalp that occurs most often in prepubescent children. Tinea capitis may be transmitted by shared use of contaminated hairbrush, by contact with fomites or by direct physical contact with an infected person. Occasionally, outbreak of tinea capitis would happen under some special conditions. Last year, we found an outbreak of tinea capitis in a school due to Microsporum canis. In epidemiological study, we performed the prevalence survey to all of the exposed persons by physical examinations and mycological laboratory tests, including KOH preparation and fungal cultures. We also investigated the environment in the school. In molecular typing study of the M. canis isolated from patients and the environment, random primer amplification polymorphic DNA (RAPD) method, the specific amplification of subrepeat element in the ribosomal DNA nontranscribed spacer (NTS), and the analysis of DNA sequence in the intertranscribed spacer (ITS) of rDNA were performed. The total number of exposed children was seventy-one, among them forty-two were attacked by tinea capitis. The ratio between boy and girl was 13:1. The ages of the patients was ranged from 3.5 years old to 10 years old. Four patients bred cat or dog as pet. Most patients appeared noninflammatory type of tinea capitis and several patients were inflammatory type. Under microscopic examination the invaded hair were all ectothrix. The pathogens isolated from these patients were M. canis. And we also isolated M. canis from the carpet and the pillowcase in the school. The patterns of total strains of M. canis in the RAPD method and PCR amplification of the rDNA NTS region study were identical, and the isolates from patients and the environment contained the same DNA sequences in the ITS region. The outbreak of tinea capitis was caused by M. canis. The M. canis isolated from patients and from the environment were probably the same origin.  相似文献   

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