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PubMed1978

[Demonstration of an alkali PAS-effect using periodic acid at low concentration (author's transl)].

It has been shown that an isolated KOH PAS-effect of epithelial mucosubstances in the colonic mucosae of the rat can be demonstrated also without the conventionally used preliminary oxidation/reduction step. The method is based on the use of strongly diluted periodic acid after previous treatment of tissue sections with ethanolic KOH. As the positive reacting material has been proven to be sensitive against treatment with neuraminidase the modified KOH PAS-reaction should be related to the presence of acylated sialic acid residues in mucosubstances of the colonic mucosae of the rat.

Animals↗
PubMed1990

[Application of "mild" periodic acid oxidation to the ultrahistochemical detection of sialic acid-containing compounds in human fallopian tube epithelium].

2 histochemical methods were used to analyse the carbohydrates in the human oviductal epithelium, namely the periodic acid-semicarbazide-silver proteinate and the 'mild' periodic acid-thiosemicarbazide-silver proteinate technique. It was possible to detect periodate reactive substances and sialic acid-containing compounds, namely separately. The 'mild' periodic acid oxidation is a selective technique for the histochemical demonstration of the existence of unsubstituted acylneuraminic acids. The ultrahistochemical results show that, firstly, periodate reactive particles are located in the cytoplasm of ciliated and nonciliated cells. The material appears in form of beta-granula (glycogen). Secondly, we could observe fine granular reactive products in the lysosomal-like and lipid droplet-like structures. In these subjects the positive granula encircling ring-like the homogeneous matrix occur in the peripheral zone of the morphological substrate investigated. By the way, these granula situated in the periphery of organelles are alone reacting after staining with 'mild' periodic acid-thiosemicarbazide-silver proteinate; this means, the glycogen particles are unstained. Thus the findings indicate that, in the cells of the human oviductal epithelium, sialic acid-containing compounds are ultrahistochemically visualized by 'mild' periodic acid oxidation in combination with thiosemicarbazide and silver proteinate.

Cilia↗
PubMed1982

Inhibition of rat brain microsomal (Na+ + K+)-ATPase and K+-p-nitrophenylphosphatase by periodic acid.

The effects of mild periodate exposure on the kinetics of (Na+ + K+)-ATPase and K+-p-nitrophenylphosphatase were studied using rat cerebral microsome preparations. Fifty percent inhibition of both enzyme activities was attained near 3 microM periodate concentrations. This inhibition was biphasic with time. Mg2+-ATPase and Mg2+-p-nitrophenylphosphatase activities were much less inhibited by periodate. Periodate inhibition was partially reversed by dimercaprol and dithiothreitol but not by diffusion. The possible reaction products formic acid, formaldehyde, glyceraldehyde, and acetaldehyde had no inhibitory effects in similar concentrations. Periodate exposure produced no detectable changes in the activation of (Na+ + K+)-ATPase by Na+, K+, Mg2+, or ATP. Residues shared by both (Na+ + K+)-ATPase and K+-p-nitrophenylphosphatase are both critical to hydrolytic function and sensitive to mild oxidation by periodate.

4-Nitrophenylphosphatase↗
PubMed2007

Spectrofluorimetric determination of trace amounts of coenzyme A using a terbium ion-ciprofloxacin complex probe in the presence of periodic acid.

A new spectrofluorimetric method was developed for the determination of trace amounts of coenzyme A (CoA). In the presence of periodic acid (H5IO6), CoA can remarkably enhance the fluorescence intensity of the Tb3+-ciprofloxacin (CIP) complex at 545 nm in a buffer solution at pH 5.4; the enhanced fluorescence intensity of the Tb3+ ion is proportional to the concentration of CoA. The optimal conditions for the determination of CoA were also investigated. The linear range and the detection limit for the determination of CoA were 6.08x10(-6)-1.64x10(-5) and 2.1x10(-8) mol L-1, respectively. This method is simple, practical and relatively free of interference from coexisting substances, and can be successfully applied to assess CoA in injection and biological samples. Moreover, the enhancement mechanism of the fluorescence intensity of the CoA-Tb3+-CIP system in the presence of H5IO6 is also discussed.

Animals↗
PubMed1989

Thiosemicarbazide used after periodic acid makes methenamine silver staining of renal glomerular basement membranes faster and cleaner.

The periodic acid-methenamine silver staining technique, which is frequently used for demonstrating the renal glomerular basement membrane, requires a high degree of skill, and in some cases it may be difficult to obtain a good result. To overcome such difficulty and inconsistency, we have improved the method by performing methenamine silver staining after oxidation with periodic acid and subsequent application of thiosemicarbazide. In this procedure, this semicarbazide enhanced the reaction of methenamine silver with the glomerular basement membrane and the reaction was completed within a shorter time in comparison with the conventional method. This modification also eliminated any nonspecific reaction with the surface of the glass slide and the solution container and yielded excellent and reproducible results irrespective of the fixation method and material employed. It was also found to stain the renal glomerular basement membrane of rabbits, which is demonstrable only with difficulty by the conventional method.

Animals↗
PubMed2003

Chromium(VI) oxide catalyzed oxidation of sulfides to sulfones with periodic acid.

A highly efficient and selective oxidation of sulfides to sulfones with periodic acid catalyzed by CrO(3) is described. A variety of electron-rich and electron-deficient sulfides were oxidized to sulfones with 2 mol % CrO(3) in acetonitrile at room temperature in excellent yields. Sulfides with other readily oxidized functional groups were selectively oxidized to sulfones in high yields with 10 mol % CrO(3) in ethyl acetate/acetonitrile at -35 degrees C.

Journal Article↗
PubMed1989

Enhanced protein phosphorylation, IL-2 receptor expression, and IL-2 production precede cellular proliferation in lymphocytes oxidized by periodic acid.

Increased rates of protein phosphorylation, IL-2 receptor (IL-2R) expression, IL-2 production and DNA synthesis were quantified in rat lymphocytes oxidized by periodic acid (H5IO6). Enhanced phosphorylation of 97, 59 and 37 to 29 kDa proteins in lymphocytes was detected at 18 and 36 hrs post-oxidation, whereas IL-2R expression and IL-2 elaboration were at their maximum by 24 hrs. The number of oxidized cells entering the S-phase of the cell cycle and their thymidine incorporation rates reached their maximum at 72 hrs. These results indicate that H5IO6-induced blastogenesis elicits a progression of responses temporally similar to those of lymphocytes stimulated by lectins.

Animals↗
PubMed1983

Comparative activation response of splenocytes oxidized by periodic acid and selenium dioxide.

Murine splenocytes were activated by selenium dioxide (SeO2) oxidation of cell membranes, as evidenced by increased tritiated thymidine (3H-TdR) incorporation. In contrast to splenocyte activation by periodic acid (H5IO6), the SeO2-induced response was not inhibited by neuraminidase degradation of cell membranes prior to oxidation, nor by the prior hydroxylamine (NH2OH) addition reaction. However, reduction by borohydride (NaBH4), as a preliminary step to the oxidation by SeO2 and H5IO6, inhibited the subsequent cell activation. Sequential oxidation by H5IO6 and SeO2 increased the cell stimulation index versus the response elicited after one step oxidation by SeO2 or H5IO6. The reverse order of the sequential oxidation depressed the stimulation index relative to oxidation solely by H5IO6, but not by SeO2. It is concluded that the activation of splenocytes by SeO2 is triggered primarily by the conversion of cell membrane carbonyls into corresponding dicarbonyls.

Animals↗
PubMed1975

Periodic acid methenamine silver (pam) staining of the human subcutaneous lymphatic vessel.

The fine structure of the subcutaneous lymphatic vessel taken from the dorsum pedis of the human adult was investigated without and after impregnation by periodic acid methenamine silver (PAM). To check the stainability of another tissue, the renal glomerulus of the rat was also examined in the same way as outlined above. The membrane system of various cells stains positive. No special surface coat of the endothelial cell of the lymphatic vessel was detected. The fine intracellular filament as well as a continuous basal lamina of the endothelial cell were almost PAM-negative, although a part of the basal lamina was occasionally weakly positive. The chemical composition of the basal lamina of the lymphatic vessel is considered to differ from that of the glomerular blood capillary of the kidney, which is PAM-positive. This difference is thought to be due to the smaller polysaccharide content in the former than in the latter.

Adult↗
PubMed1994

Periodic acid Schiff reaction in childhood lymphoblastic leukaemia. The Medical Research Council Working Party on Childhood Leukaemia.

AIMS: To assess the prevalence and degree of periodic acid Schiff (PAS) positivity in blast cells from children with lymphoblastic leukaemia (ALL); its association with other disease characteristics; and its clinical importance in predicting the outcome of treatment. METHODS: Marrow slides from entrants to a large United Kingdom multicentre ALL trial (UKALL X) were batch processed and assessed blind for PAS positivity by one morphologist. Patients were classified into groups A, B, and C, corresponding to less than 1% PAS positive cells, 1-10%, and over 10%, respectively. Their PAS pattern was then compared with other clinical and pathological features of ALL and with treatment outcome. RESULTS: Slides from 921 children were examined of which 371 (40%) were categorised as group A, 324 (35%) as group B, and 226 (25%) as group C. There was a clear association between the presence of blast cell vacuoles on Romanowsky staining and PAS positivity. Group A (PAS negative) patients included a disproportionate excess of those with L2 morphology, those under 2 or over 6 years of age, those with an initial white cell count over 50 x 10(9)/l, those with a T or null cell immunophenotype, and those with chromosomal abnormalities other than "high hyperdiploidy". Four years from diagnosis, group C patients had an 8% disease free survival advantage over those in group A (2p = 0.01). This was irrespective of initial white cell count, but not of immunophenotype or the presence of vacuoles. CONCLUSIONS: Strong PAS positivity is a feature of "common" ALL and is particularly associated with blast cell vacuoles. It does occasionally occur in other disease subtypes with or without vacuoles. It predicts a better response to current treatment, but not independently of other cell characteristics.

Adolescent↗
PubMed2002

Lectin-histochemical and -cytochemical study of periodic acid Schiff-positive lysosome granules as a histological feature of the female mouse kidney.

Renal proximal straight tubules (PST) of the female mouse contain periodic acid Schiff-positive lysosome granules. An excellent example of this is found in the kidneys of female DBA/2Cr mice. In the present study, lectin-histochemistry showed that lectin-positive granules occur in the PST of DBA/2Cr mice. Out of twenty-one lectins studied, the granules bound WGA, s-WGA, LEL, STL, DSL, GSL-II, VVL, RCA-I, ECL, PSA, LCA and PHA-E. Such granules were also observed in the proximal convoluted tubules (PCT). In addition, heterogeneous binding to the SBA or DBA was observed in the PST. Lectin-cytochemistry for s-WGA, STL, VVL, RCA-I, ECL and PSA, showed that: 1) lysosomes bind a higher level of s-WGA or STL than VVL, RCA-I, ECL or PSA; 2) PSA binding is similar in PST and PCT; 3) there are many PCT lysosomes that are negative for s-WGA, STL, VVL, RCA-I, and ECL lectin binding; and 4) s-WGA binding is highly specific to the lysosomes of the PST. Based on the binding specificities of each lectin, it was suggested that the mannose content of PST and PCT lysosomes is similar, and that PST lysosomes have a high level of N-acetylglucosamine, N-acetylgalactosamine, galactose or galactosyl (beta 1, 4) N-acetylglucosamine.

Animals↗
PubMed1986

Pararosaniline or acriflavine-Schiff staining of epoxy embedded tissue after periodic acid oxidation in ethanol: a method suitable for morphometric and fluorometric analysis of glycogen.

A method for preparing tissue sections for automatic image analysis of glycogen is described. Large semithin sections of epoxy embedded tissue fixed in glutaraldehyde-osmium were stained with Schiff reagent and acriflavine (fluorescent staining) after resin removal and periodic acid oxidation in ethanol. We found it essential to avoid tissue rehydration before final staining. The Schiff stain permits an assessment of the cellular volume of glycogen, and the acriflavine allows a fluorometric evaluation of glycogen density.

Acriflavine↗
PubMed1992

Periodic acid thiosemicarbazide gelatin methenamine silver (PATSC-GMS) staining for transmission electron microscopy.

A new electron microscopic method is described in which superior staining of basement membranes, collagen fibers and glycogen particles in various tissues was achieved. This method uses a gelatin methenamine silver solution applied to the ultrathin sections on nickel grids after oxidation in a periodic acid. The staining results were excellent and tissue components were evenly stained with no background silver grains. This method proved to be consistent, reproducible and reliable.

Animals↗
PubMed1989

Senile plaque-like structures: observation of a probably unknown type of senile plaque by periodic-acid methenamine silver (PAM) electron microscopy.

Numerous diffuse senile plaque-like structures (SPLSs) were found in the cerebral cortex from cases with dementia of the Alzheimer type by means of the methenamine-Bodian method. SPLSs varied in shape and size. They were never recognized in the original Bodian, PAS and Congo red preparations, but were positive with anti-beta-protein immunostaining and periodic-acid methenamine silver (PAM) methods, which are thought to specifically stain amyloid substance. With PAM electron microscopy, we found sparse aggregations of amorphous, often ramified, structures with fine granular silver deposits in SPLS. Routine electron microscopic examination on the same portion where SPLS were confirmed by PAM electron microscopy revealed amorphous, partially fibrous structures. These structures might be amyloid or amyloid-precursor substance. In SPLSs only a few degenerated neurites and astrocytic processes with glycogen granules were seen. We consider SPLSs to be a kind of senile plaque.

Adult↗