RESUMO
Methods of preparing fungal samples for chemical analysis are briefly considered. The basic principles employed in laser microscopy are outlined. The applications of the technique to mycology and to plant biology are discussed. Such a method allows chemical information to be obtained on the same sample and permits the detection of 74 elements in the periodic system of Mendeleev from lithium (3) to uranium (92). The preparative procedures are evaluated according to general histochemical principles. This technique requires little specimen preparation and has the advantage of not requiring large masses of tissue.
Assuntos
Fungos/análise , Histocitoquímica/métodos , Lasers , Técnicas Microbiológicas , Elementos Químicos/análise , Fungos Mitospóricos/análise , Penicillium/análise , Análise EspectralRESUMO
The electron microprobe analyzer was used to study the chemical compositions of some pathogenic fungi for humans. Elementary analysis was based on the characteristic X-ray spectra generated by the electrons passing through the specimens. This is a non-destructive method allowing to perform multiple elementary analysis in the same tissue. In order to increase our understanding of pathogenic fungi, small pieces of fungi tissue were analyzed. The species examined were Histoplasma capsulatum, Blastomyces dermatitidis and Fonsecaea pedrosoi.
Assuntos
Ascomicetos/análise , Blastomyces/análise , Eletrólitos/análise , Histoplasma/análise , Cálcio/análise , Cloro/análise , Microanálise por Sonda Eletrônica , Fósforo/análise , Enxofre/análiseRESUMO
X-ray microanalysis has been applied to the study of pathogenic fungi for the acquisition of chemical information. The technique of combined scanning electron microscopy and wavelength dispersive spectrometry is described. The chemical analysis depends on the characteristic x-ray spectrum excited by the electrons passing through the sample. This spectrum is analyzed by x-ray wavelength dispersion using crystal spectrometers. All the elements of the periodic system above beryllium can be detected with good sensitivity.
Assuntos
Microanálise por Sonda Eletrônica/métodos , Fungos/análise , Micologia/métodos , Penicillium/análiseRESUMO
Analytical electron microscopy combines the techniques of high-resolution electron microscopy and high-sensitivity X-ray microanalysis of samples. Spectrometry of the elements (characteristic X-rays produced by a scanning electron microprobe) was employed to detect some elements of Mendeleev's classification in pathogenic fungi for humans. X-ray microanalysis applied in wavelength dispersive spectrometry was used to study Coccidioïdes immitis, Paracoccidioïdes brasiliensis and Trichosporum cutaneum.