894 resultados para Iron hematoxylin staining
Resumo:
Due to its unique properties, iron hematoxylin has been traditionally recommended for staining intestinal protozoa. This process can be simplified by reducing the number of steps and periods of permanence of the slides in some of the liquids used, without detriment to the quality of the results. Thus iron hematoxylin becomes adequate for routine use. Hematoxylin is a natural dye extracted from Haematoxylon campechianum, of the family Leguminosae. It must first be 'ripened', i.e. oxidized to hematein, which reacts with ferric ammonium sulphate to produce the ferric lake (iron hematoxylin), a basic dye. Iron hematoxylin most frequently stains regressively, i.e. the slides are first overstained and then differentiated.
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There is no paucity of methods for diagnosing Cryptosporidium spp. infection. The merits of immunoassays notwithstanding, microscopic identification of Cryptosporidium spp. oocysts in fecal samples remains an important diagnostic procedure. It owes the persistence of its use to such characteristics as dispensing with expensive equipment and kits, requiring only basic laboratory facilities, and having a low probability of false positive results when permanent slides are prepared, which can be re-examined in case of doubt. Cryptosporidium spp. oocysts can be readily identified in fecal smears prepared according to a regressive iron hematoxylin staining technique. The number of steps and their duration, as well as costs, were reduced to a minimum without loss of image quality and permanence of the preparations.
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INTRODUCTION: Studies strongly indicate Dientamoeba fragilis as one of the causes of diarrhea in human immunodeficiency virus (HIV) patients. METHODS: The objective of the present study was to evaluate the prevalence of D. fragilis associated with the causes of diarrhea in 82 HIV/ AIDS patients hospitalized at the Instituto de Infectologia Emílio Ribas from September 2006 to November 2008. RESULTS: In total, 105 samples were collected from 82 patients. Unprotected sex was the most frequent cause of HIV infection (46.3%), followed by the use of injectable or non-injectable drugs (14.6%). Patients presented with viral loads of 49-750,000 copies/ mL (average: 73,849 ± 124,850 copies/mL) and CD4 counts ranging of 2-1,306 cells/mm³ (average: 159 ± 250 cells/mm³). On an average, the odds of obtaining a positive result by using the other techniques (Hoffman, Pons and Janer or Lutz; Ritchie) were 2.7 times higher than the chance of obtaining a positive result by using the simplified iron hematoxylin method. Significant differences were found between the methods (p = 0.003). CONCLUSIONS: The other techniques can detect a significantly greater amount of parasites than the simplified iron hematoxylin method, especially with respect to Isospora belli, Cryptosporidium sp., Schistosoma mansoni, and Strongyloides stercoralis, which were not detected using hematoxylin. Endolimax nana and D. fragilis were detected more frequently on using hematoxylin, and the only parasite not found by the other methods was D. fragilis.
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The protozoan parasite Giardia lamblia is responsible for a common intestinal infection in all regions of the world. In this study, four laboratory tests were evaluated for diagnostic reproducibility in the detection of this infection: Coprotest®, Direct modified method, Faust method and iron-hematoxylin staining. Positive diagnoses were tested for association with factors such as the age group and gender of the subject and the month when the sample was taken. Feces of 200 children in the Araraquara region (SP, Brazil) were examined by all four methods and the results compared. G. lamblia was found to be the most frequent parasite and 8.0% of the children showed giardiasis. There was no apparent correlation with gender, but most of the parasites were found in three- to five-year-olds. The highest frequency of infection occurred in January. The most reliable diagnostic results for G. lamblia were achieved by combining at least two methods of good reproducibility, i.e. Coprotest-Faust, Direct-Faust or Coprotest-Direct (A > 0.81).
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The objective was to estimate the prevalence of Blastocystis hominis, to evaluate the effectiveness of different techniques for its diagnosis as well as to estimate the prevalence of other intestinal parasites in the community of Campo Verde, a district of Pitanga. The work was carried out from August to October 2004. Samples of feces from children and adults were collected and submitted to the techniques of direct wet mount, flotation in zinc sulphate solution, tube sedimentation, sedimentation in formalin-ether and staining by Kinyoun and iron hematoxylin methods. From 181 studied individuals, 128 (70.7%) showed protozoa and/or helminths in stool samples. The most prevalent species were Endolimax nana (33.7%); B. hominis (26.5%); Giardia lamblia (18.2%); Entamoeba coli (17.1%); Ascaris lumbricoides (16.6%); Iodamoeba bütschlii (9.4%); and ancylostomatidae (7.7%). B. hominis was only identified by the techniques of direct wet mount, sedimentation in formalin-ether and staining by iron hematoxylin, though the latter was less sensitive than the other methods. The high frequency of B. hominis demonstrated by this study indicates the need to include laboratory techniques that enable identification of the parasite on a routine basis.
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Blastocystis homins is a protozoan that causes an intestinal infection known as human blastocystosis. This infection is diagnosed by means of parasitological examination of stools and by permanent staining techniques. The present study was developed to evaluate the frequency of Blastocystis hominis infection among inhabitants of the Araraquara region, State of São Paulo, and to compare different methods for investigating this protozoan in feces samples. Evaluations on 503 stool samples were performed by means of direct fresh examination and using the techniques of Faust et al., Lutz and Rugai et al. In addition, the iron hematoxylin, trichrome and modified Kinyoun staining techniques were used. Out of the 503 samples examined, 174 (34.6%) were found to be positive for the presence of intestinal parasites. The most frequent protozoa and helminths were Entamoeba coli (14.6%) and Strongyloides stercoralis (6.7%), respectively. Blastocystis hominis was present in 23 (4.6%) fecal samples, with a predominately pasty consistency and without characterizing a condition of diarrhea. Despite the low frequency of Blastocystis hominis found in the Araraquara region, compared with other regions of Brazil, it is important to perform laboratory diagnostic tests for this protozoan. Its finding in fecal material is indicative of food and drinking water contamination. Since the transmission route for this parasite is accepted to be oral-fecal, this implies that the population needs guidance regarding hygiene and basic sanitation measures as a means for controlling health problems caused by enteroparasites.
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Definite hyperplasia of cells occurs in the skin lesions of the infectious myxoma of rabbits, more visible in such stages in which the intercellular basophilic substance is rather scanty (fig. 2). The increase in number of cells is the result of simplified forms of mitosis (modified type of mitosis, pseudoamitosis) which might readily be mistaken for amitosis in their final stages. Budding (figs. 20, 28, 29, 30) as well as constriction of the nucleus (figs. 18, 31, 32), and the formation of giant-cells (figs. 33, 34) are not rare. During the entire process the nuclear membrane does not desintegrate as in typical mitosis. Division of the cytoplasm following division of the nucleus has been demonstrated (fig. 17). Typical mitosis is practically absent. The cells which undergo hyperplasia present remarkable changes in their dimension, shape, and structure. The nucleus and cell-body are considerably enlarged (figs. 6, 7, 8). The shape of the nucleus is modified (figs. 8, 10, 15). Hypertrophy of nuclein, either as an intranuclear network (spireme?, figs. 9, 23), or in the form conspicuous, deeply staining masses which appear not to be homogeneous but to be composed of small particles closely clumped ("mulberries"?, figs. 12, 13, 14, 25, 26) occurs in most cells. While some of these pictures are probably related to necrosis of the cells as started by most of the previous workers, it is lekely that some of them may represent developmental stages of the modified mitosis (pseudoamitosis) here reported. In fact, fine cytological details not ordinarily preserved in necrotic cells (figs. 35, 36, 37) may be demonstrated in the socalled myxoma-cells subtted to approved cytological methods of study (fixation in B-15 and P. F. A.-3, staining in iron-hematoxylin).
Resumo:
Blastocystis hominis é um protozoário, causador de infecção intestinal denominada blastocistose humana, cujo diagnóstico é realizado pelo exame coproparasitológico e por meio de técnicas de coloração permanente. Este estudo foi desenvolvido para avaliar a freqüência da infecção por Blastocystis hominis em habitantes da região de Araraquara/SP, bem como comparar diferentes métodos para a pesquisa desse protozoário em amostras de fezes. Foram estudadas 503 amostras de fezes submetidas ao exame direto a fresco, às técnicas de Faust e cols, Lutz e de Rugai e cols, além das colorações pela hematoxilina férrica, tricrômio e de Kinyoun modificada. Entre as 503 amostras examinadas, 174 (34,6%) apresentaram-se positivas para a presença de parasitas intestinais. O protozoário e o helminto mais freqüentes foram Entamoeba coli (14,6%) e Strongyloides stercoralis (6,7%), respectivamente. Blastocystis hominis foi observado em 23 (4,6%) amostras fecais com consistência predominantemente pastosa, não caracterizando quadro diarréico. Apesar da baixa freqüência de Blastocystis hominis encontrada na região de Araraquara, comparativamente a outras regiões brasileiras, é importante a realização do diagnóstico laboratorial desse protozoário. O encontro de Blastocystis hominis em material fecal é indicativo de contaminação de alimentos e água de consumo, desde que se admita a rota de transmissão oral-fecal desse parasita, o que implica na orientação da população sobre as medidas de saneamento básico e higiene como meio para se controlar problemas de saúde ocasionados pelos enteroparasitas.
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Aluminum (Al) toxicity is a major worldwide agricultural problem. At low pH, Al speciates into the soluble and phyto-toxic form Al(3+), inhibiting the root growth and affecting plant development. In Brazil, agriculture in acidic soils with elevated concentration of Al has significantly increased in the last decades. Therefore, in order to achieve efficient agriculture practices, the selection of plant cultivars with improved Al resistance has become crucial in this type of soils. In this work we have evaluated the Al resistance of six genotypes of grapevine rootstocks. The grapevine hardwood cuttings were grown in nutrient solution in the absence and presence of 250 and 500 mu M Al at pH 4.2. The phenotypic indexes of relative root growth, fresh and dry root weight, root area, hematoxylin staining profile, and Al content were evaluated for all six genotypes. These phenotypic indexes allowed us to identify the `Kober 5BB`, `Gravesac`, `Paulsen 1103`, and `IAC 766` grapevine rootstocks genotypes as the ones with the highest resistance to Al. Likewise, `IAC 572` and `R110` genotypes were the most Al-sensitive cultivars. We evaluated the root organic acid exudation profile in the most Al-resistant (`Kober 5BB`) and most Al-sensitive (`R110`) in plantlets cultivated in vitro in the absence and presence of 100, 200, and 400 mu M of Al. Among several compounds detected, citrate was the only organic acid related to the Al resistance phenotype observed in the `Kober 5BB` genotype. The high constitutive citrate exudation observed in `Kober 5BB` strongly suggests that exudation of this particular organic acid may impart Al-resistance/a melioration in grapevine.
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Tetratrichomonas didelphidis (Hegner & Ratcliffe, 1927) Andersen & Reilly, 1965 is a flagellate protozoan found in the intestine, cecum, and colon of Didelphis marsupialis. The parasitic protozoa used in this study was found and isolated in the intestine of opossums in Pavlova starch-containing medium in Florianópolis, State of Santa Catarina, Brazil, from D. marsupialis and Lutreolina crassicaudata. The strains were cultivated in Diamond medium without maltose and with starch solution, pH 7.5 at 28°C. The specimens were stained by the Giemsa method and Heidenhain's iron hematoxylin. The light microscopy study of the trophozoites revealed the same morphologic characteristics as specimens previously described.
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Aluminum (Al) toxicity is a major factor limiting barley growth in acid soils, and genotypes with adequate level of tolerance are needed for improving barley adaptation in Brazil. To study the inheritance of Al tolerance in Brazilian barleys, cultivars Antarctica 1, BR 1 and FM 404 were crossed to sensitive Kearney and PFC 8026, and intercrossed. Parental, F1, F2 and F6 generations were grown in nutrient solution containing 0.03, 0.05 and 0.07 mM of Al and classified for tolerance by the root tip hematoxylin staining assay. Tolerant by sensitive F2 progenies segregated three tolerant to one sensitive, fitting the 3:1 ratio expected for a single gene. The F6 populations segregated one tolerant to one sensitive also fitting a monogenic ratio. The F2 seedlings from crosses among tolerant genotypes scored the same as the parents. Since the population size used would allow detection of recombination as low as 7%, the complete absence of Al sensitive recombinants suggests that tolerance in these cultivars is most probably, controlled by the same gene. Thus, the potential for improving Al tolerance through recombination of these genotypes is very low and different gene sources should be evaluated.
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Root elongation, hematoxylin staining, and changes in the ultrastructure of root-tip cells of an Al-tolerant maize variety (Zea mays L. C 525 M) exposed to nutrient solutions with 20 μm Al (2.1 μm Al3+ activity) for 0, 4, and 24 h were investigated in relation to the subcellular distribution of Al using scanning transmission electron microscopy and energy-dispersive x-ray microanalysis on samples fixed by different methods. Inhibition of root-elongation rates, hematoxylin staining, cell wall thickening, and disturbance of the distribution of pyroantimoniate-stainable cations, mainly Ca, was observed only after 4 and not after 24 h of exposure to Al. The occurrence of these transient, toxic Al effects on root elongation and in cell walls was accompanied by the presence of solid Al-P deposits in the walls. Whereas no Al was detectable in cell walls after 24 h, an increase of vacuolar Al was observed after 4 h of exposure. After 24 h, a higher amount of electron-dense deposits containing Al and P or Si was observed in the vacuoles. These results indicate that in this tropical maize variety, tolerance mechanisms that cause a change in apoplastic Al must be active. Our data support the hypothesis that in Al-tolerant plants, Al can rapidly cross the plasma membrane; these data clearly contradict the former conclusions that Al mainly accumulates in the apoplast and enters the symplast only after severe cell damage has occurred.
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This study focuses on the use of hemotoxylin-eosin staining plus fluorescence microscopy for the investigation of elastic fibers in some elastic cartilages. We have observed that elastic fibers are consistently imaged by the proposed procedure and the resolution attained is similar to that obtained with the classical Weigert's fuchsin-resorcin. The results also demonstrate that elastin autofluorescence gives little or no contribution to the final fluorescence and that the use of the confocal laser scanning microscope adds to the resolution, permits the use of thicker sections and reveals of minute structural features. We conclude that this is a relevant tool in elastin research.
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Oxidative stress and inflammatory processes strongly contribute to pathogenesis in Duchenne muscular dystrophy (DMD). Based on evidence that excess iron may increase oxidative stress and contribute to the inflammatory response, we investigated whether deferoxamine (DFX), a potent iron chelating agent, reduces oxidative stress and inflammation in the diaphragm (DIA) muscle of mdx mice (an experimental model of DMD). Fourteen-day-old mdx mice received daily intraperitoneal injections of DFX at a dose of 150 mg/kg body weight, diluted in saline, for 14 days. C57BL/10 and control mdx mice received daily intraperitoneal injections of saline only, for 14 days. Grip strength was evaluated as a functional measure, and blood samples were collected for biochemical assessment of muscle fiber degeneration. In addition, the DIA muscle was removed and processed for histopathology and Western blotting analysis. In mdx mice, DFX reduced muscle damage and loss of muscle strength. DFX treatment also resulted in a significant reduction of dystrophic inflammatory processes, as indicated by decreases in the inflammatory area and in NF-κB levels. DFX significantly decreased oxidative damage, as shown by lower levels of 4-hydroxynonenal and a reduction in dihydroethidium staining in the DIA muscle of mdx mice. The results of the present study suggest that DFX may be useful in therapeutic strategies to ameliorate dystrophic muscle pathology, possibly via mechanisms involving oxidative and inflammatory pathways.
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Background & Aims: Nonalcoholic steatohepatitis (NASH) is a chronic liver disease that occasionally progresses to cirrhosis but usually has a benign course. The aim of this study was to investigate the role of the hemochromatosis mutation Cys282Tyr in development of the mild hepatic iron overload found in some patients with NASH and its association with hepatic damage in these patients. Methods: Fifty-one patients with NASH were studied. The presence of the Cys282Tyr mutation was tested in all patients, and the data were analyzed with respect to the histological grade of steatosis, inflammation, Perls' staining, hepatic iron concentration (HIC), and serum iron indices. Results: Thirty-one percent of patients with NASH were either homozygous or heterozygous for the Cys282Tyr mutation. This mutation was significantly associated with Perls' stain grade (P < 0.005), HIC (P < 0.005), and transferrin saturation percentage (P < 0.005) but not with serum ferritin levels. Linear regression analysis showed that increased hepatic iron (Perls' stain or HIC) had the greatest association with the severity of fibrosis (P < 0.0001). Conclusions: The Cys282Tyr mutation is responsible for most of the mild iron overload found in NASH and thus has a significant association with hepatic damage in these patients. Heterozygosity for the hemochromatosis gene mutation therefore cannot always be considered benign.