APMIS. Supplementum最新文献

{"title":"Occurrence, selection and spread of resistance to antimicrobial agents used for growth promotion for food animals in Denmark.","authors":"F M Aarestrup","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Unlabelled: </strong>14.1</p><p><strong>Introduction: </strong>This thesis is based on a number of monitoring and research programmes initiated at the Danish Veterinary Laboratory with the aim to determine the occurrence, selection and spread of resistance to antimicrobial agents used for growth promotion. The thesis gives a brief overview of the use, consumption, function and benefit of antimicrobial growth promoters and a more thorough description of the potential resistance problems arising by the use of these agents. 14.2 THE USE OF ANTIMICROBIAL AGENTS IN A HISTORICAL PERSPECTIVE: Soon after the introduction of antimicrobial agents for therapy of bacterial infections in humans and animals, the growth promoting effect of antimicrobial agents was observed, and since the beginning of the 1950'ties antimicrobial agents have been included in feed for food animals as a way to improve growth and reduce production costs. 14.3 CONSUMPTION OF ANTIMICROBIAL GROWTH PROMOTERS: Exact figures on the consumption of antimicrobial agents for clinical and growth promoting purposes are very difficult to get, and estimates are only available for a few countries. In Denmark, the total annual consumption of antimicrobial agents for growth promotion increased from 67 tonnes to 116 tonnes from 1989 to 1995. After the ban on avoparcin in 1995 the total consumption of growth promoters decreased to 94 tonnes. An increase up to 107 tonnes took place during 1996 and 1997, but during 1998, the consumption decreased to approximately 49 tonnes. The data that are available for different countries show that the use of antimicrobial agents for growth promotion normally equals or exceeds the usage of antimicrobial agents for therapy for food animals. Based on the information available, it can be estimated that the financial sale of antimicrobial agents for animals amounts to approximately 25% to 35% of the world-wide sale, of which the use of antimicrobial agents as feed additives is at least 50%. 14.4 MODE OF ACTION OF ANTIMICROBIAL GROWTH PROMOTERS: The mode of action of antimicrobial growth promoters is not fully understood. However, the main effects are believed to be a reduction of the growth of bacteria in the intestinal tract and thereby less microbial degradation of useful nutritients, and the prevention of infections with pathogenic bacteria. 14.5 BENEFIT FROM THE USE OF ANTIMICROBIAL GROWTH PROMOTERS: Numerous studies on the economic benefit of the use of antimicrobial growth promoters have been performed. The growth response is normally larger in young animals than in older animals. Large variations in the estimates have been observed, but in general a improvement in growth rate and feed utilisation has been observed. 14.6 SUSCEPTIBILITY AND RESISTANCE TO ANTIMICROBIAL GROWTH PROMOTERS: The definition of a bacterium as susceptible or resistant to an antimicrobial agent ultimately depends on clinical outcome. Since the exact mode of action of antimicrobial ","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"101 ","pages":"1-48"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21948190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular dissection of Mycoplasma hominis.","authors":"S A Ladefoged","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>M. hominis is commonly found as part of the normal flora in the female genital tract, but several studies have shown that it may be involved in a variety of urogenital infections. The basis for clinical manifestations in some patients has varyingly been attributed to host and M. hominis factors. The host factors involved in the infection process are largely unknown. M. hominis have no cell wall and outer membranes, and at present it seems plausible that M. hominis possesses genetic systems allowing the bacteria in vivo to alter its antigenic structure on the membrane surface and consequently circumvent the host immune system. The studies of M. hominis have shown that the antigenic variation is pronounced between surface exposed membrane proteins from different isolates. The genetic background for this variation has been investigated for three surface exposed membrane proteins: P120, Lmp, and Vaa. P120 and P120' are similar proteins in M. hominis without any homology to other known proteins. A hypervariable region in the otherwise conserved P120 protein seems to be very antigenic in patients with immunologically verified M. hominis infection. The remaining part of P120 as well as the entire P120' protein do not seem to elicit significant antibody formation. Two genes in M. hominis, lmp1 and lmp3, contain numerous highly similar 0.5 kb tandem repeats at their 3'-end. The proteins, Lmp1 and Lmp3, are synthesized from the lmp1 and lmp3 genes, respectively. Lmp1 shows size variation among M. hominis isolates. M. hominis isolates investigated in detail show that the size variation of Lmp1 corresponds to the variation in number of 0.5 kb repeats contained within the lmp1 gene. Lmp3 appears to have a lesser tendency to size variation. M. hominis isolates were found with deletions involving the lmp1 stop codon leading to translation of the downstream gene lmp2 and expression of a chimeric Lmp1-Lmp2 protein. The number of repeated elements in the lmp1 gene of a M. hominis isolate correlates with the extent of anti-Lmp antibody induced agglutination between the bacteria. Vaa is a protein involved in cell adherence. vaa is a single copy gene containing tandem repeated elements like the lmp gene family. The number of repeats in the Vaa protein differs between M. hominis isolates leading to size variation. It has been suggested that the number of repeated elements is of importance in the bacteria-host adhesion process. Beside the size variation Vaa demonstrates phase variation due to frequent frame shift mutation in a specific region near the 5'-end of the structural gene. Based on the investigations of M. hominis and other mycoplasmas several genetic mechanisms seem to be responsible for the antigenic variation of surface exposed membrane proteins in mycoplasmas: 1) variation in protein size due to insertions or deletion of repeated elements in the structural gene, 2) presence of multi-gene families, and 3) phase variation due to mutations in the promot","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"97 ","pages":"1-45"},"PeriodicalIF":0.0,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21574164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Postantibiotic effect in vitro.","authors":"K Fuursted","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"90 ","pages":"1-23"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21061438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterial degradation of immunoglobulin A1 in relation to periodontal diseases.","authors":"E V Grønbaek Frandsen","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Periodontal diseases affect millions of people world wide. Prevention and treatment of these diseases require considerable attention from the individual as well as society and cause great expenses. Understanding disease etiology and mechanisms of pathogenesis is a prerequisite for optimal treatment strategies. The highly variable speed of periodontal destruction and in some sites persistence for years of deep pockets without further periodontal destruction points to the significance of individual bacterial species in the complex subgingival microflora for pathogenesis. Destruction of periodontal tissue occurs when the load of bacterial virulence factors overcomes the local immune defense. One way of doing this is by bacterially-induced degradation of IgA which is considered to mediate its protective functions in an anti-inflammatory way and to down-regulate inflammation through inhibition of IgG- and IgM-mediated activities. A competent IgA system may be of particular significance in chronic inflammatory diseases, as periodontal diseases, where the inflammatory reaction in itself probably is the main cause of destruction. In these cases, degradation of IgA may serve the purpose of immune evasion for the bacteria and at the same time may induce a relatively increased activity in the inflammation-stimulating part of the immune system which may aggravate periodontal destruction. Both gram-positive rods, streptococci, and Veillonella species from the subgingival microflora induce an altered immunoelectrophoretic mobility of IgA1 indicative of removal of terminally positioned sialic acid. Quantitative determination of residual carbohydrate content of IgA1 after incubation with bacterial cells of Gram-positive rods has confirmed that they remove sialic acid, and in addition to that, only minor amounts of carbohydrates. Apart from serving a nutritional purpose, desialylation of IgA may also serve a purpose of immune evasion. Glycosylation and, in particular sialic acid protects glycoproteins, including immunoglobulins, against proteolytic enzymes and deglycosylation of antibodies increase their sensitivity to proteolytic degradation and inhibit the Fc-mediated effector functions that mediate antigen disposal. Extensive proteolytic degradation of IgA1 is induced by a number of bacterial species often associated with periodontal diseases, including P. gingivalis, Pr. intermedia, and Pr. nigrescens. These species produce enzymes of broad proteolytic activity, that also may degrade immunoglobulins of other isotopes, complement factors, iron-containing plasma proteins etc. Extensive hydrolysis of immunoglobulins induced by these bacteria serve a nutritional purpose and is essential for growth of other bacteria in mixed cultures. It also has an obvious detrimental effect on the defence potential of the specific humoral immune system. These bacteria seem to be essential for the transmissibility of experimental infections in animals with mixtures of oral ","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"87 ","pages":"1-54"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21061431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The plasminogen activation system in lung cancer--with special reference to the prognostic role in \"non-small cell lung cancer\".","authors":"H Pappot","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"92 ","pages":"1-29"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21230763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnosis of urogenital Chlamydia trachomatis infection by use of DNA amplification.","authors":"L Ostergaard","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Numerous studies on DNA amplification and diagnosis of C. trachomatis infections have been performed since the first PCR for detection of C. trachomatis in clinical samples was described in 1990, but optimal sample preparation procedures are still lacking. The major problem in evaluating the diagnostic performance of the DNA amplification methods is that there is no clinical or microbiological reference standard for C. trachomatis infection. The evaluated diagnostic performance will therefore always be a reflection of of the chosen comparator(s). Despite this, it seems that the DNA amplification methods are more sensitive than the cell culture techniques and the techniques based on immunology. Compared with the tests based on immunology the specificity is also improved, which makes the DNA amplification methods useful for sample types contaminated with organisms cross-reacting in the immunologically based methods, i.e. pharyngeal and rectal swab samples. However, the specificity and thereby the predictive value of a positive test is not optimal. Since the predictive value of a positive test is highly influenced by the prevalence in the tested population, evaluation of applied tests is constantly needed, especially since the prevalence may be expected to decrease with intensified test activity and due to changes in safe sex practices after the advent of AIDS. The improved sensitivity of the DNA amplification methods allows the use of sample material in which the content of Chlamydia organisms is lower than in conventional swab samples, i.e. urine, semen, and vaginal secretions can be used as sample material. these samples can be obtained by the individuals themselves, and since transport conditions seem less critical for the test performance, samples can also be taken in the privacy of the home and subsequently mailed by the individual directly to the diagnostic laboratory. Such strategy for testing has led to improved partner tracing and universal screening, compared with traditional swab examinations at physicians' offices. Tests with an optimal diagnostic performance have not yet been reached, and several sample categories have not been studied sufficiently. The societal implications of the use of self-collected samples and universal screening have not been studied in full, but a milestone for new strategies in detection and preventing urogenital C. trachomatis epidemics has been reached with the availability of DNA amplification techniques.</p>","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"89 ","pages":"5-36"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21061436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epithelial salivary gland tumours. An immunohistological and prognostic investigation.","authors":"M H Therkildsen","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"95 ","pages":"1-39"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21456015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pharmacological effects of epidermal growth factor (EGF) with focus on the urinary and gastrointestinal tracts.","authors":"L Vinter-Jensen","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Epidermal growth factor (EGF) belongs to a family of growth factor ligands and receptors. At present, five ligands have been recognized which as EGF exert their effects via binding to the same EGF receptor. The family has three other receptors erbB2, erbB3, and erbB4, which have their own ligands (the heregulins). The system is ubiquitously distributed in mammals, and has important roles in normal development, and in regenerative and neoplastic growth. Mouse and human EGF were discovered in 1962 and 1975 by Stanley Cohen and Harry Gregory, respectively, due to EGFs potent systemic effects. EGF accelerated eyelid opening in newborn mice and inhibited gastric acid secretion in humans. Already in the late thirties, a factor in human urine was recognized which prevented or accelerated healing of experimental damage in the gastrointestinal tract. This factor appeared to be EGF. Around 1980, an effect of commercial interest was described-EGF caused shedding of the fleece in sheep. In line with the original observations, several studies have examined effects of EGF on developmental processes. Amongst other effects, EGF accelerates lung and intestinal maturation before birth and in newborn mammals. Due to the possible use of EGF in the wool industry, it was mandatory to know more about EGF. Amongst other effects in mature sheep and other animals are haemodynamic changes, changes in electrolyte homeostasis, and endocrinological changes. In relation to experimental damage, the therapeutic potential of systemic EGF has been demonstrated in all parts of the gastrointestinal tract, in the kidneys, in the liver and in the trachea. EGF has even been tried in humans in gastric ulcer healing and in necrotising enterocolitis. Studies on prolonged treatment with EGF have first recently appeared. We described effects of 4-5 weeks of treatment in Goettingen minipigs and in rats, and two other groups described effects in monkeys and in rats. In summary, species differences were observed. The species of higher order were most sensitive to treatment with EGF. EGF did not consistently change the total body weight despite EGF consistently reduced circulating levels of insulin-like growth factor I (IGF-I) in Goettingen minipigs as well as in rats. Low circulating levels of IGF-I are usually associated with retarded growth. This review mostly focuses on the organs which appeared to be most sensitive to EGF, the urinary and gastrointestinal tracts including the liver and the pancreas. The histopathological changes consisted mainly of epithelial proliferations in the gastrointestinal, urinary and respiratory tracts. These findings match the knowledge obtained from animals overexpressing the EGF agonist, transforming growth factor alpha (TGF alpha), and the mice with a knock out of the gene encoding for the EGF receptor. EGF receptor hyperstimulation (TGF alpha overexpression) in the context of the whole animal leads to epithelial proliferations whereas hypostimulation (","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"93 ","pages":"1-42"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21290948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Moraxella (Branhamella) catarrhalis: clinical, microbiological and immunological features in lower respiratory tract infections.","authors":"J J Christensen","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"88 ","pages":"1-36"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21061433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic characteristics of coagulase-negative staphylococci: typing and antibiotic susceptibility.","authors":"J O Jarløv","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The present thesis deals with various aspects of handling coagulase-negative staphylococci (CoNS) in the local clinical microbiology laboratory. CoNS are normal inhabitants of the skin and mucus membranes and are increasingly being recognised as opportunistic pathogens causing infection in the immunocompromised host, in particular patients with indwelling plastic devices. In particular the finding of CoNS in specimens which should normally be sterile, such as blood cultures, is of interest. The isolation of the same strain of an opportunistic pathogen, such as CoNS, enhance the likelihood of the bacteria causing infection. Multiple antibiotic resistance, in particular methicillin resistance, is frequent among CoNS hospital-strains on a global scale. beta-lactam antibiotics are the most valuable antibiotics for the treatment of infection with susceptible CoNS. A reliable method for the detection of methicillin resistance, and hereby resistance to all beta-lactam antibiotics, is therefore important. A simple identification method, Minibact-S, has been developed. Minibact-S can identify the CoNS species, which are the most frequently occurring in human specimens. Furthermore, Minibact-S can subtype Staphylococcus epidermidis. Another phenotypic typing method, lectin typing, has been developed for typing S. epidermidis. Lectin typing involves the binding of various biotinylated lectins to the surface of whole immobilised cells of CoNS. Lectins are proteins or glycoproteins which bind specifically to various glycans. When the lectins: Wheat Germ Agglutinin (WGA), Soy Bean Agglutinin (SBA), Concanavalin A (ConA), and Lens Culinaris Agglutinin (LCA) were included, typing of S. epidermidis gave a discriminatory power of the same magnitude as found for DNA-plasmid profile analysis. Lectin typing could be used as a supplementary typing method for S. epidermidis in the local clinical microbiology laboratory, since the method is simple, reproducible and does not require expensive and sophisticated equipment. Various typing schemes for S. epidermidis, i.e. typing which involves several typing methods, have been tested: lectin typing, DNA-plasmid profile analysis, antibiotic susceptibility testing, phage typing, and slime production lectin typing, antibiotic susceptibility testing, biotyping (Minibact-S), phage typing antibiotic susceptibility testing and biotyping (Minibact-S) For use as a \"first line\" typing scheme in the local clinical microbiology laboratory, the typing of S. epidermidis by combined antibiotic susceptibility testing and biotyping is easy to handle. Antibiotic susceptibility testing should include antibiotics from several groups of antibiotics having different resistance mechanisms. Antibiotic susceptibility among Danish CoNS-strains from blood cultures was studied. A major diversity in species distribution and antibiotic susceptibility was found between different Danish regions, for example methicillin resistant CoNS accounted for 40","PeriodicalId":77006,"journal":{"name":"APMIS. Supplementum","volume":"91 ","pages":"1-42"},"PeriodicalIF":0.0,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21101174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}