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1.
Int J Syst Evol Microbiol ; 66(9): 3477-3484, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27266728

RESUMO

The mycoplasma strain ST 57T was isolated from the trachea of a clinically healthy, free-ranging white stork nestling in Nielitz, Mecklenburg-Western Pomerania, Germany. Strain ST 57T grew in fried-egg-shaped colonies on mycoplasma (SP4) agar plates and was dependent on sterol for growth. The organism fermented glucose and did not hydrolyse arginine or urea. The optimal growth temperature was 37 °C, with a temperature range from 23 to 44 °C. Strain ST 57Tcould not be identified as a representative of any of the currently described mycoplasma species by alignment of the 16S rRNA gene sequence or 16S-23S intergenic transcribed spacer region, or by immunobinding assays. Thus, this organism appears to be a representative of a novel species, for which the name Mycoplasma ciconiae sp. nov. is proposed. The type strain is ST 57T (=ATCC BAA-2401T=DSM 25251T). Four further strains of this species are included in this description (ST 24=DSM 29908, ST 56 Clone 1=DSM 29054, ST 99=DSM 29909, ST 102=DSM 29010). The prevalence of this mycoplasma species in clinically healthy, white stork nestlings in northern Germany was determined. Our species-specific PCR detected 57.8 % (48/83) of the samples positive for M. ciconiae sp. nov. As this species appears to be widespread in the healthy free-ranging white stork population, we conclude that this species is either apathogenic or an opportunistic pathogen in white storks.


Assuntos
Aves/microbiologia , Mycoplasma/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Alemanha , Mycoplasma/genética , Mycoplasma/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Traqueia/microbiologia
2.
Mol Imaging Biol ; 22(3): 486-493, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31650483

RESUMO

PURPOSE: The endeavor of deciphering intricate phenomena within the field of molecular medicine dictates the necessity to investigate tumor/disease microenvironment real-time on cellular level. We, hereby, design simple and robust intravital microscopy strategies, which can be used to elucidate cellular or molecular interactions in a fluorescent mouse model. PROCEDURES: We crossbred transgenic TIE2GFP mice with nude BALB/c mice, allowing the breeding of immunocompetent and immunodeficient mouse models expressing green fluorescent protein (GFP) in vascular endothelium. Then, we surgically exposed various tissues of interest to perform intravital microscopy. RESULTS: By utilizing simple tissue preparation procedures and confocal or two-photon microscopy, we produced high-resolution static snapshots, dynamic sequences, and 3D reconstructions of orthotopically grown mammary tumor, skin inflammation, brain, and muscle. The homogenous detection of GFP expressed by endothelial cells and a combination of fluorescence agents enabled landmarking of tumor microenvironment and precise molecular tagging. CONCLUSION: Simple intravital microscopy procedures on TIE2GFP mice allowed a real-time multi-color visualization of tissue microenvironment, underlining that robust microscopy strategies are relatively simple and can be readily available for many tissues of interest.


Assuntos
Neoplasias da Mama/patologia , Microscopia Intravital/métodos , Microscopia Confocal/métodos , Receptor TIE-2/genética , Animais , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos Transgênicos , Receptor TIE-2/química , Receptor TIE-2/metabolismo , Microambiente Tumoral
3.
Avian Dis ; 52(1): 94-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18459303

RESUMO

Mycoplasmas are pathogens of different avian species, but the role of Mycoplasma in raptors is not yet completely determined. As Mycoplasma isolation and identification present several difficulties, species-specific polymerase chain reactions (PCRs) for the detection of mycoplasmas found in birds of prey (Mycoplasma buteonis, Mycoplasma corogypsi, Mycoplasma falconis, and Mycoplasma gypis) were established. The specificity of the PCR methods were investigated using known avian Mycoplasma reference strains and isolates as well as related bacteria and was found to be specific. Amplificons obtained with these PCRs from field samples showed no false-positive results in restriction enzyme analysis and sequencing. The sensitivities of the different PCR assays varied between 50 fg and 1 pg DNA. Twenty-five tracheal swabs from healthy captive birds of prey were investigated by culture and immunobinding assay as comparison to the PCRs. Mycoplasmal DNA was detected in 88% of the samples, with negative results only from vultures. Mycoplasma falconis and M. buteonis were regularly found in falcons, and M. gypis was found in a common buzzard. Mycoplasma corogypsi was not demonstrated. Several isolates could not be differentiated using an immunobinding assay as well as the described PCR methods.


Assuntos
Doenças das Aves/microbiologia , Portador Sadio/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Aves Predatórias/microbiologia , Animais , Sequência de Bases , Portador Sadio/microbiologia , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Mycoplasma/classificação , Infecções por Mycoplasma/microbiologia , Reação em Cadeia da Polimerase/normas , Mapeamento por Restrição/veterinária , Sensibilidade e Especificidade , Especificidade da Espécie
4.
Scientometrics ; 84(3): 785-793, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20700372

RESUMO

Bibliometric counting methods need to be validated against perceived notions of authorship credit allocation, and standardized by rejecting methods with poor fit or questionable ethical implications. Harmonic counting meets these concerns by exhibiting a robust fit to previously published empirical data from medicine, psychology and chemistry, and by complying with three basic ethical criteria for the equitable sharing of authorship credit. Harmonic counting can also incorporate additional byline information about equal contribution, or the elevated status of a corresponding last author. By contrast, several previously proposed counting schemes from the bibliometric literature including arithmetic, geometric and fractional counting, do not fit the empirical data as well and do not consistently meet the ethical criteria. In conclusion, harmonic counting would seem to provide unrivalled accuracy, fairness and flexibility to the long overdue task of standardizing bibliometric allocation of publication and citation credit.

5.
Scientometrics ; 85(2): 567-579, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20949112

RESUMO

A collection of coauthored papers is the new norm for doctoral dissertations in the natural and biomedical sciences, yet there is no consensus on how to partition authorship credit between PhD candidates and their coauthors. Guidelines for PhD programs vary but tend to specify only a suggested range for the number of papers to be submitted for evaluation, sometimes supplemented with a requirement for the PhD candidate to be the principal author on the majority of submitted papers. Here I use harmonic counting to quantify the actual amount of authorship credit attributable to individual PhD graduates from two Scandinavian universities in 2008. Harmonic counting corrects for the inherent inflationary and equalizing biases of routine counting methods, thereby allowing the bibliometrically identifiable amount of authorship credit in approved dissertations to be analyzed with unprecedented accuracy. Unbiased partitioning of authorship credit between graduates and their coauthors provides a post hoc bibliometric measure of current PhD requirements, and sets a de facto baseline for the requisite scientific productivity of these contemporary PhD's at a median value of approximately 1.6 undivided papers per dissertation. Comparison with previous census data suggests that the baseline has shifted over the past two decades as a result of a decrease in the number of submitted papers per candidate and an increase in the number of coauthors per paper. A simple solution to this shifting baseline syndrome would be to benchmark the amount of unbiased authorship credit deemed necessary for successful completion of a specific PhD program, and then monitor for departures from this level over time. Harmonic partitioning of authorship credit also facilitates cross-disciplinary and inter-institutional analysis of the scientific output from different PhD programs. Juxtaposing bibliometric benchmarks with current baselines may thus assist the development of harmonized guidelines and transparent transnational quality assurance procedures for doctoral programs by providing a robust and meaningful standard for further exploration of the causes of intra- and inter-institutional variation in the amount of unbiased authorship credit per dissertation.

6.
PLoS One ; 3(12): e4021, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19107201

RESUMO

Authorship credit for multi-authored scientific publications is routinely allocated either by issuing full publication credit repeatedly to all coauthors, or by dividing one credit equally among all coauthors. The ensuing inflationary and equalizing biases distort derived bibliometric measures of merit by systematically benefiting secondary authors at the expense of primary authors. Here I show how harmonic counting, which allocates credit according to authorship rank and the number of coauthors, provides simultaneous source-level correction for both biases as well as accommodating further decoding of byline information. I also demonstrate large and erratic effects of counting bias on the original h-index, and show how the harmonic version of the h-index provides unbiased bibliometric ranking of scientific merit while retaining the original's essential simplicity, transparency and intended fairness. Harmonic decoding of byline information resolves the conundrum of authorship credit allocation by providing a simple recipe for source-level correction of inflationary and equalizing bias. Harmonic counting could also offer unrivalled accuracy in automated assessments of scientific productivity, impact and achievement.


Assuntos
Autoria , Bases de Dados Bibliográficas/normas , Viés de Publicação , Publicações/ética , Editoração/ética , Logro , Interpretação Estatística de Dados , Eficiência , Humanos , Modelos Biológicos , Projetos de Pesquisa , Ciência/métodos , Má Conduta Científica
7.
Science ; 323(5914): 583; author reply 583, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19179512

Assuntos
Autoria , Bibliometria
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