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1.
Summary The histochemical demonstration of hetero--galactosidase (glucosidase) has been attempted in sections and zymograms of rabbit, monkey and human intestine and of rat kidney.The leakage of this enzyme from unfixed sections was prevented by the use of cold microtome sections adherent to semipermeable membranes. Methods with -D-glucosides and galactosides of 6-Br-2-naphthol (postincubation azocoupling with Fast Blue B as well as simultaneous azocoupling with hexazonium-p-rosaniline), of -naphthol (simultaneous azocoupling with hexazonium-p-rosaniline) and of 4-Cl-5-Br-3-indolyl (with ferricyanide, phenazonium methosulfate or nitro BT and without any oxidation agent) were used an evaluated concerning the specificity, localization ability and inhibition of enzyme activity. Pretreatment of sections with distilled water or saline and inhibition by p-Cl-mercuribenzoate, glucono- and galactono-lactones were used for the characterization of the demonstrated enzyme activity.6-Br-2-naphthyl--D-glucoside is the most specific substrate for hetero--galactosidase. It is not split by lactase and acid -galactosidase. Only lysosomal -glucosidase can interfere. Because the latter enzyme is membrane-bound the difference in color intensity between untreated and prewashed sections are due to hetero--galactosidase. Only localization on the cellular (not intracellular) level can be achieved, however.The simultaneous azocoupling method with -naphthyl--D-glucoside and hexazonium-p-rosaniline enables a very good localization of hetero--galactosidase in the rabbit intestine. Due to a great inhibition exerted by hexazonium-p-rosaniline on the enzyme activity the method is unsuitable for the detection of hetero--galactosidase in zymograms and in the human intestine. Interference of lactase (or lactase-phlorizine hydrolase complex) is to be considered. The lysosomal -glucosidase does not seem to interfere.Indigogenic methods are not sensitive either. With ferricyanide as an oxidation agent it was not possible to detect the activity of hetero--galactosidase in zymograms and in sections. This is possibly due to overoxidation of indigo. The same holds true for phenazonium methosulfate used for the processing of zymograms. However, it was possible to reveal the activity of hetero--galactosidase in sections of the rabbit and monkey intestine with phenazonium methosulfate as oxidation agent. Nitro BT enhanced the coloration both in zymograms and in sections. In the latter case diffusion artifacts cannot be prevented, however. The interference of lactase, lysosomal -galactosidase and possibly of lysosomal -glucosidase (depending on the glycoside used) is always to be considered.Hetero--galactosidase was localized in the cytoplasm (particularly in the supranuclear region) of differentiated enterocytes covering the villi of the rabbit (the highest activity), monkey and human (the lowest activity) intestine. In crypt enterocytes and in cells of Brunner's glands the activity was lower. The occurrence of a low activity of hetero--galactosidase in the brush border of enterocytes of the rabbit intestine was also demonstrated.A proximodistal gradient was observed in the rabbit and monkey intestine, the upper jejunum displaying the highest activity.In jejunal biopsies of patients with celiac sprue (in the acute stage of the disease) the activity of hetero--galactosidase was lowered. No changes of activity were observed in jejunal biopsies of patients with isolated deficiencies of lactase or sucrase.In the rat kidney the enzyme was demonstrated particularly in the cytoplasm of cells of proximal convoluted tubules.  相似文献   
2.
OBJECTIVE: To investigate the possibility of a correct cytologic diagnosis of cervical and endometrial carcinoma with other genital organ involvement. STUDY DESIGN: From uteri removed during hysterectomy due to cervical (33 cases) and endometrial (44 cases) cancer, samples were taken by cytobrush or spatula from the ectocervix, endocervix and endometrium of uteri opened longitudinally. Smears and cytosediments were stained by the Papanicolaou polychrome method. Moreover, acid beta-galactosidase activity was demonstrated in serial cytosediments by the indigogenic method of Lojda. From quenched tissue samples taken from the same sites as those for cytology, a series of cryostat sections was prepared and stained by hematoxylin and eosin or azure A, or subjected to the reaction for acid beta-galactosidase. RESULTS: In 17 of 33 patients with cervical cancer, the same type of cancer was also found in smears of the endocervix and endometrium. In six patients the type of cancer was different. Of 44 patients with endometrial cancer, 16 had an endocervical malignancy of the same type. In seven cases the type of cancer was different. The reaction for acid beta-galactosidase helped in the differentiation between squamous (negative reaction in cancer cells) and cylindrocellular (positive reaction) cancer in cytologic preparations. CONCLUSION: Before treatment, it is necessary to determine if there is involvement of the endocervix in endometrial cancer and of the endometrium in cervical cancer. Routine cytologic examination supplemented by the reaction for acid beta-galactosidase proved to be useful for this purpose.  相似文献   
3.
Glucocorticoids (GCs) are steroid hormones produced by the adrenal cortex in reaction to stress stimuli. GCs production is not stable over a 24-hour period; the plasma concentration peaks in the morning (approximately upon awakening) and then the plasma levels decrease, reaching the nadir in the evening. In our experiments, the levels of cortisol, cortisone, DHEA and DHEAS were tested in young female pigs (n=23) during heart catheterization at two different day times (in the morning and in the afternoon). The non-parametric Mann-Whitney test for statistical analysis was used. We found only minimal statistical differences in studied markers between the morning and afternoon group (p>0.05). The absence of circadian variation in GCs levels could originate either at an early age of our experimental pigs, or in stressful conditions on the experiment day, or most likely the day before (e.g. social isolation, fasting, transport, and catheterization), respectively. We can conclude there is no difference in the stress load between morning and afternoon experiments, and therefore we can assume the stress load is not a limiting factor for the timing when catheterization should be preferably performed.  相似文献   
4.
In alkali burned rabbit corneas activities of beta-glucuronidase, N-acetyl-beta-D-glucosaminidase and acid beta-galactosidase were studied histochemically in various time intervals after the traumatization. The technic with semipermeable membranes was employed. Within four days after the injury enzyme activities in the traumatized area were almost lacking. The corresponding activities in the unaffected part of the cornea were within the norm. On the 7th day enzyme activities were on an increase (but still subnormal) in the traumatized area. This area was surrounded by a zone of keratocytes with high levels of enzyme activities. This was particularly remarkable in keratocytes subjacent to the epithelium. The activation of all enzymes studied was present in the basal layer of the epithelium and in the endothelium as well. On the 14th day enzyme activities in the traumatized area were nearly restored and on the 32nd day they could not be distinguished from the normal cornea. Beta-galactosidase displayed a relatively maximal increase in the activity of all enzymes investigated.  相似文献   
5.
6.
A comparison of instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) results for sizefractionated atmospheric aerosols (“coarse” and “fine” fractions with an equivalent aerodynamic diameter of 2–10 Μm and < 2 Μm, respectively, or the PM10 fraction) showed that PIXE yielded significantly lower results for the PM10 and coarse fractions, especially for elements with a low Z resulting from a particle size effect. Somewhat lower PIXE results were also obtained for the fine fraction of atmospheric aerosols. A correction is also needed for irregularly shaped deposits of combustion aerosols collected by a cascade impactor in 11 size fractions ranging from 0.016 to 14.3 Μm, as well as for thick samples of fly and bottom ashes. An equivalent layer thickness (ELT) model is proposed to correct the matrix effects in PIXE. The approaches for the calculation of ELT using a comparison of PIXE and INAA results or by comparing PIXE results obtained using two different incident proton beam energies (1.31 and 2.35 MeV) are described. The correction for the ash pellets and irregular deposits are also discussed.  相似文献   
7.
137Cs is one of the most important radionuclides released in the course of atmospheric nuclear weapon tests and during accidents in nuclear power plants such as that in Chernobyl, Ukraine, or Fukushima, Japan. The aim of this study was to compare 137Cs and 40K concentrations in particular species of mushrooms from selected locations in the Bohemian Forest (Czech: ?umava), Czech Republic, where a considerable contamination from the Chernobyl accident had been measured in 1986. Samples were collected between June and October 2014. Activities of 137Cs and 40K per dry mass were measured by means of a semiconductor gamma spectrometer. The 137Cs values measured range from below detection limit to 4300?±?20 Bq kg?1, in the case of 40K from 910?±?80 to 4300?±?230 Bq kg?1. Differences were found between individual locations, due to uneven precipitation in the course of the movement of the radioactive cloud after the Chernobyl accident. There are, however, also differences between individual species of mushrooms from identical locations, which inter alia result from different characteristics of the soil and depths of mycelia. The values measured are compared with established limits and exposures from other radiation sources present in the environment. In general, it can be stated that the values measured are relatively low and the effects on the health of the population are negligible compared to other sources of ionizing radiation.  相似文献   
8.

Background

Thellungiella halophila (also known as Thellungiella salsuginea) is a model halophyte with a small plant size, short life cycle, and small genome. It easily undergoes genetic transformation by the floral dipping method used with its close relative, Arabidopsis thaliana. Thellungiella genes exhibit high sequence identity (approximately 90% at the cDNA level) with Arabidopsis genes. Furthermore, Thellungiella not only shows tolerance to extreme salinity stress, but also to chilling, freezing, and ozone stress, supporting the use of Thellungiella as a good genomic resource in studies of abiotic stress tolerance.

Results

We constructed a full-length enriched Thellungiella (Shan Dong ecotype) cDNA library from various tissues and whole plants subjected to environmental stresses, including high salinity, chilling, freezing, and abscisic acid treatment. We randomly selected about 20 000 clones and sequenced them from both ends to obtain a total of 35 171 sequences. CAP3 software was used to assemble the sequences and cluster them into 9569 nonredundant cDNA groups. We named these cDNAs "RTFL" (RIKEN Thellungiella Full-Length) cDNAs. Information on functional domains and Gene Ontology (GO) terms for the RTFL cDNAs were obtained using InterPro. The 8289 genes assigned to InterPro IDs were classified according to the GO terms using Plant GO Slim. Categorical comparison between the whole Arabidopsis genome and Thellungiella genes showing low identity to Arabidopsis genes revealed that the population of Thellungiella transport genes is approximately 1.5 times the size of the corresponding Arabidopsis genes. This suggests that these genes regulate a unique ion transportation system in Thellungiella.

Conclusion

As the number of Thellungiella halophila (Thellungiella salsuginea) expressed sequence tags (ESTs) was 9388 in July 2008, the number of ESTs has increased to approximately four times the original value as a result of this effort. Our sequences will thus contribute to correct future annotation of the Thellungiella genome sequence. The full-length enriched cDNA clones will enable the construction of overexpressing mutant plants by introduction of the cDNAs driven by a constitutive promoter, the complementation of Thellungiella mutants, and the determination of promoter regions in the Thellungiella genome.  相似文献   
9.
Studies on protoplasts isolation were carried out with mature pollen grains of 29 samples of species of Allium aflatunense, A. cepa, A. fistulosum, A. karataviense, A. longicuspis, A. nutans, A. odorum, A. sativum and A. schoenoprasum. Surface sterilized pollen grains drifted from crushed anthers were incubated in an enzyme solution containing 1% (w/v) cellulase Onozuka R-10, 1% (w/v) Macerozyme R-10, 0,5 mol l-1 sucrose and the basal salts of Nitsch medium. Protoplasts were released within 3 to 120 min, either from the pollen grain, through a slightly disturbed germination pore (narrow aperture), or through a wider aperture, when the exine surrounding the germination pore was disturbed. For the first time, protoplasts were obtained from 13 genotypes of 6 Allium species, at a rate of 1 to 30% of the digested intact pollen grains, depending on the genotype.  相似文献   
10.
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