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1.
Acta Cytol ; 45(4): 499-501, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11480708

RESUMO

OBJECTIVE: To reach consensus on the application of quantitative cytochemical analysis of chromosomal and DNA aneuploidy in cervical cytopathology. CONCLUSION: The current Pap test has limited specificity to predict cancer and its truly progressive pre-malignant lesions. Infection with human papillomavirus may trigger genetic instability, hyperproliferation and immortalization of the cervical mucosa and cause cervical cancer. Several related molecular markers have been shown to be informative about this neoplastic process. Quantitative analysis of chromosomal and DNA aneuploidy has been shown to be an important tool for identifying (progression to) high grade squamous intraepithelial lesions. A high degree of standardization (material handling, calibration and quality control, measurement and interpretation of results) is required for accurate and reproducible measurements. Areas for further study are presented.


Assuntos
DNA/análise , Histocitoquímica/métodos , Programas de Rastreamento , Papillomaviridae , Neoplasias do Colo do Útero/patologia , Aneuploidia , Feminino , Humanos , Infecções por Papillomavirus/diagnóstico , Sensibilidade e Especificidade , Infecções Tumorais por Vírus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética
2.
Nat Commun ; 5: 3311, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24548928

RESUMO

The subfamily of the Lemnoideae belongs to a different order than other monocotyledonous species that have been sequenced and comprises aquatic plants that grow rapidly on the water surface. Here we select Spirodela polyrhiza for whole-genome sequencing. We show that Spirodela has a genome with no signs of recent retrotranspositions but signatures of two ancient whole-genome duplications, possibly 95 million years ago (mya), older than those in Arabidopsis and rice. Its genome has only 19,623 predicted protein-coding genes, which is 28% less than the dicotyledonous Arabidopsis thaliana and 50% less than monocotyledonous rice. We propose that at least in part, the neotenous reduction of these aquatic plants is based on readjusted copy numbers of promoters and repressors of the juvenile-to-adult transition. The Spirodela genome, along with its unique biology and physiology, will stimulate new insights into environmental adaptation, ecology, evolution and plant development, and will be instrumental for future bioenergy applications.


Assuntos
Araceae/crescimento & desenvolvimento , Araceae/genética , Genoma de Planta/genética , Água Doce , Dados de Sequência Molecular
7.
Ber Wiss ; 19(2-3): 131-43, 1996.
Artigo em Alemão | MEDLINE | ID: mdl-11630273

RESUMO

In the First World War representatives of the university discipline of psychology took the opportunity to apply their expertise in the armed forces. The initial undertakings in the German Empire and in the USA show some similarities and marked disparities. A comparison of events and circumstances in these principal belligerent states is linked with a sketch of their importance for the further development of psychology as an academic specialty and an emerging profession.


Assuntos
Testes Psicológicos , Psicologia Militar , Psicofísica , Guerra , Alemanha , História do Século XX , Estados Unidos
8.
Anal Quant Cytol Histol ; 23(4): 268-72, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11531141

RESUMO

Fluorescence in situ hybridization (FISH) allows the direct localization of DANN and RNA sequences on chromosomes, in cells and in tissue. The technique is based on hybridization between target sequences of single-strand DNA of chromosomes or cell nuclei with marked complementary specimens. The signal is amplified using fluorochrome-marked specific antibodies and made visible under a microscope. Signals from painted chromosomes, stained subchromosomal regions or localized single probes are generally visible when an epifluorescence microsope is used. In order to view and display different fluorochromes, single filter sets, as well as double and triple bandpass filters, are in use. For multiple fluoroscence imaging, lenses with high numerical aperture, mostly oil immersion systems, are recommended. In conventional photomicrography, triple exposure on high-speed film (e.g., 400-1,000 ASA) is more or less the limitation. Opto=electronic methods using a CCD and laser summing techniques have considerably extended the application range of multiple fluorescence techniques. By means of digitized images, simultaneous detection of multiple-labelled objects and ratio imaging up to 24 colors are possible today. Current FISH approaches are based on chromosome-painting probes to distinguish all 24 chromosomes by their unique spectral signatures.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Hibridização in Situ Fluorescente/métodos , Microscopia de Fluorescência/métodos , Núcleo Celular , Mapeamento Cromossômico/métodos , Coloração Cromossômica/métodos , Sondas de DNA , Corantes Fluorescentes , Humanos , Microscopia Confocal
9.
Fortschr Med ; 94(27): 1476-8, 1976 Sep 23.
Artigo em Alemão | MEDLINE | ID: mdl-971897

RESUMO

A new microscope concept is described whereby the individual main functions of a universal microscope are performed by box-type, square-based modules which can be combined at will. The main characteristics of the new Axiomat microscope are the quality of its optics, its universality and stability.


Assuntos
Microscopia/instrumentação
10.
Artigo em Alemão | MEDLINE | ID: mdl-829632

RESUMO

The polymyositis can in my view be classed with the autoimmunopathies. This classification is supported with the aid of a survey of experimental findings. Consequently a theoretical basis for the justification of an immunosuppressive therapy emerges. The significance of the glucocorticoide in the treatment programme of polymyositis is brought out and the experience with cytostatica (especially Azathioprin, Methotrexat and Cyclophosphamid) obtained up to now by separate observation are dealt with in a short review of the literature and the two own cases, and--because such case report has no representative value--comprised in a pronsional conclusion. Controls of the erythrocyte sedimentation rate, the blood count, the fibrinogen level and the lymphocyte transformation test have proved a reliable measure for an optimal immunosuppressive effect. Finally an incontrolled administration of cytostatic agents is warned of with reference to mutagenic, teratogenic and oncogenic zequelae.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Imunossupressores/uso terapêutico , Miosite/tratamento farmacológico , Adulto , Animais , Doenças Autoimunes/imunologia , Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Quimioterapia Combinada , Humanos , Imunidade Celular/efeitos dos fármacos , Miosite/imunologia , Prednisona/uso terapêutico
11.
J Microsc ; 117(3): 375-9, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-522133

RESUMO

The study of in vitro perfused individual nephron segments requires a microscope which provides: (1) easy access to the specimen for measurement of cellular solute flux and voltage; (2) an image with high resolution and contrast; (3) optical sectioning of the object at different levels; and (4) rapid recording of the morphological phenomena. This paper describes an example of commercially available apparatus meeting the above requirements, and illustrates its efficiency. The microscope is of the inverted type (Zeiss IM 35) equipped with differential-interference-contrast (DIC) with a long working distance, and an automatically controlled camera system. The microscopic image exhibits cellular and intercellular details in the unstained transporting mammalian nephron segments despite their tubular structure and great thickness and makes obvious function-structure correlations (e.g. cell volume changes); luminal and contraluminal cell borders are well resolved for controlled microelectrode impalement.


Assuntos
Túbulos Renais/citologia , Microscopia de Interferência/métodos , Animais , Túbulos Renais/fisiologia , Microscopia de Interferência/instrumentação , Perfusão , Coelhos
12.
Psychiatr Neurol Med Psychol (Leipz) ; 27(4): 225-30, 1975 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-1197459

RESUMO

The authors report on a case of sprue myopathy with myasthenic syndrome. Pathophysiological ideas are discussed and the necessity of complex examinations in myopathy-syndromes is emphasized.


Assuntos
Doença Celíaca/complicações , Doenças Musculares/complicações , Miastenia Gravis/complicações , Adulto , Doença Celíaca/metabolismo , Feminino , Glutens/metabolismo , Humanos , Doenças Musculares/metabolismo , Síndrome
13.
Microsc Acta ; 76(4): 305-15, 1975 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-239302

RESUMO

Like phase contrast, Nomarski interference contrast microscopy can be used to examine unstained specimens in biology and medicine. The properties of both contrast enhancement techniques are illustrated by various examples. The phase contrast method is especially suited for thin specimens with small differences in refractive index, whereas the interference contrast method supplies good results even of thick specimens. Interference contrast is a valuable supplement to the phase contrast method, and expands the application of microscopy in biology


Assuntos
Microscopia de Interferência , Animais , Chlorella/citologia , Clorófitas/citologia , Cnidários/citologia , Drosophila/citologia , Eucariotos/citologia , Estudos de Avaliação como Assunto , Larva/citologia , Microscopia de Interferência/métodos , Microscopia de Contraste de Fase , Glândulas Salivares/citologia
14.
Plant Physiol ; 115(3): 1057-64, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9390438

RESUMO

Jasmonic acid (JA) is rapidly biosynthesized from alpha-linolenic acid in plants upon contact with pathogens or wounding, and triggers gene activation, leading to the synthesis of defensive secondary metabolites and proteins. Despite the recent finding that its precursor, 12-oxo-phytodienoic acid (PDA), is a more powerful inducer of gene activation, interest has focused so far almost exclusively on JA. A validated negative chemical ionization-gas chromatography-mass spectrometry method has been developed that allows the simultaneous quantification of endogenous 12-oxo-PDA and JA in plant tissues. In six out of eight plant species tested maximal levels of 12-oxo-PDA exceeded peak levels of JA by approximately 3- to 5-fold after elicitation with a yeast cell wall preparation or when plants were wounded. These experiments support the hypothesis that 12-oxo-PDA acts as the predominant jasmonate signal in most plants, whereas JA remains an active metabolite of its precursor. Furthermore, JA but not 12-oxo-PDA was shown to be secreted into the medium from cultured plant cells, suggesting that JA may also act as an intercellular signal.


Assuntos
Ácidos Graxos Insaturados/biossíntese , Plantas/metabolismo , Células Cultivadas , Meios de Cultura , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes , Especificidade da Espécie
15.
J Microsc ; 132(Pt 2): 143-8, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6358508

RESUMO

The study of distribution and quantitation of a fluorescent probe in living epithelia with the aid of an inverted microscope requires that individual cells can be analysed without optical interference from adjacent cells. This report describes the application of fluorescence microscopy and fluorometry to a recently developed in vitro culture system of renal epithelial cells. Epithelial cells derived from the mammalian renal cortical collecting tubule (CT) and the thick ascending loop of Henle (TAL) are cultivated as continuous monolayers in serum-free, hormone-supplemented media. A specific mitochondrial marker (DASPMI) is added to the medium and incorporated into the cytoplasm. The microscopic image reveals that the mitochondrial fluorescence distribution differs between CT and TAL cultures. The fluorometric quantitation shows a normally distributed histogram of medium-range intensity in TAL cell cultures while CT cultures exhibit a two-peak pattern of mitochondrial fluorescence distribution among epithelial cells.


Assuntos
Técnicas Histológicas , Rim/citologia , Microscopia de Fluorescência/métodos , Compostos de Piridínio , Animais , Células Cultivadas , Células Epiteliais , Mitocôndrias/ultraestrutura , Espectrometria de Fluorescência
16.
Plant Cell Rep ; 4(6): 333-6, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24254076

RESUMO

From differentiated plants of Catharanthus roseus (L.) G. Don, a specific enzyme was isolated and named acetyl-CoA : 17-O-deacetylvindoline 17-O-acetyltransferase, acting on the biosynthetic formation of the Aspidosperma type alkaloid vindoline.The enzyme shows a high selectivity towards different substrates. The acetyl-CoA-dependent transferase also catalyses the reverse reaction by hydrolysis of the 17-O-acetyl group of vindoline in the presence of free CoA. This enzyme is localized only in vindoline-containing plant parts, but was so far not detectable in cell suspension cultures of C. roseus. The enzyme allows the synthesis of labelled vindoline with high specific activity, applicable for instance as tracer for radioimmunoassays of vindoline.

17.
Plant Cell Rep ; 6(6): 410-3, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24248920

RESUMO

Quaternary benzophenanthridine alkaloids (sanguinarine, chelerythrine, chelirubine, chelilutine and macarpine) are specifically induced by cell wall components of Penicillium and Saccharomyces in a colorless strain of Eschscholtzia californica cell suspension cultures. Classical elicitors such as the Phytophthora megasperma elicitor are inactive. The alkaloid synthesis is, however, strongly induced by certain polypeptide antibiotics. Out of 190 tested plant species the yeast elicitor provoked benzophenanthridine synthesis in 13 cultures. One of the branch point enzymes, namely the berberine bridge enzyme, catalysing the formation of (S)-scoulerine from (S)-reticuline, is strongly stimulated during the elicitation process. These results clearly demonstrate the induction of the benzophenanthridine biosynthetic pathway by microbial elicitors.

18.
J Microsc ; 163(Pt 2): 201-10, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1719207

RESUMO

The use of fast-staining DNA-specific dyes such as DAPI or Hoechst 33342/33258 has been a major problem for confocal scanning laser microscopy (CSLM) studies of intranuclear chromatin organization. Moreover, the availability of a confocal ultraviolet scanning laser microscope configuration, which allows an excitation at wavelengths of 364 nm as well as 488, 514 and 543 nm, is a prerequisite for single as well as multiple fluorescence parameter studies, especially if these studies are concerned with the precise localization of intranuclear signals. Here we report the characteristics and application of a CSLM, which was adapted for UV-excitation and therefore enables comparison of the spatial distribution of several types of signals within one preparation. In addition to multiple-parameter studies, we have also investigated the sensitivity of the system with regard to the identification of the double-stranded DNA of lampbrush chromosome loops in germinal vesicles of amphibian oocytes.


Assuntos
DNA/análise , Animais , Benzimidazóis , Bisbenzimidazol , Blastocisto/química , Linhagem Celular , Feminino , Corantes Fluorescentes , Imuno-Histoquímica , Indóis , Lasers , Camundongos , Microscopia de Fluorescência , Ovário/química , Triturus , Raios Ultravioleta , Xenopus laevis
19.
Dtsch Med Wochenschr ; 106(35): 1087-90, 1981 Aug 28.
Artigo em Alemão | MEDLINE | ID: mdl-6455282

RESUMO

A transpapillary indwelling catheter was placed in 15 patients with choledocholithiasis and threatened occlusion by stone. Ten of the 15 patients had marked biliary stasis, four had signs of acute cholangitis. In all patients E. coli was present in the gall-bladder in a concentration of greater than or equal to 10(5)/ml when the catheter was first inserted. The bacteria were sensitive to mezlocillin, at a minimal inhibitor concentration between 1.5 and 16 micrograms/ml. All patients received mezlocillin, 5 g twice daily, in a short-term infusion. Immediately before and regularly thereafter bile samples were taken to measure antibiotic concentration and bacterial counts (by membrane filtration). Mezlocillin was excreted in the bile in very high concentrations in patients without biliary stasis. But while the concentrations were markedly lower in those with stasis, they were still 10 to 100 times the minimum inhibitory concentration of mezlocillin against the appropriate strains. In keeping with the high mezlocillin concentration, bacterial counts fell much more quickly in the patients without stasis than in those with alkaline phosphatase concentration above 250 U/l. These differences were even more marked after two or three days. Bacterial elimination from bile was complete in two of three patients with normal alkaline phosphatase activity, but in only one of five in whom it was elevated.


Assuntos
Colangite/tratamento farmacológico , Penicilinas/uso terapêutico , Idoso , Fosfatase Alcalina/sangue , Bile/análise , Colangite/complicações , Colelitíase/complicações , Colestase/complicações , Escherichia coli , Feminino , Humanos , Masculino , Mezlocilina , Pessoa de Meia-Idade
20.
Psychiatr Neurol Med Psychol (Leipz) ; 31(5): 267-72, 1979 May.
Artigo em Alemão | MEDLINE | ID: mdl-583473

RESUMO

Some of the radiopharmaceuticals presently recommended for cisternoscintigraphy were compared, in experiments on animals, for their effects upon bioelectric activity. On relaxed cats, electroencephalography did not show any effects upon bioelectric activity for 198 Au and 169 Yb Ca DTPA. One test animal each of seven and six cats examined using 169 Yb DTPA and 131 J HSA showed changes in the electroencephalogram subsequent to suboccipital application.


Assuntos
Eletroencefalografia , Radioisótopos/administração & dosagem , Animais , Encéfalo/diagnóstico por imagem , Gatos , Radioisótopos de Ouro , Injeções Espinhais , Radioisótopos do Iodo , Cintilografia , Itérbio
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