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At least 19 recordsLinked to original sources
PubMed1978

Preservation of erythrocytes using metabolic regulators and mutrients. V. Inosine and methylene blue.

Methylene blue and inosine have been shown to stimulate glycolytic metabolism in the erythrocytes, increasing the concentration of 2.3-diphosphoglycerate (2,3-DPG), which is necessary for hemoglobin function, by regulating oxidative metabolism and providing a five-carbon nutrient for glycolysis, respectively. However, a recent study suggested that the methylene blue effect was dependent on the presence of inosine. This study was designed to establish, if possible, the existence of a methylene blue effect and to confirm the usefulness of inosine. The optimal concentration of inosine for increasing 2,3-DPG synthesis in a CPD-adenine preservative is confirmed to be 10--15 mM. Concentrations of 2,3-DPG were maintained in the erythrocytes at normal or higher levels for 21 days of storage with 10 or 15 mM inosine, whether the methylene blue was present or not. However, when methylene blue was present, 2,3-DPG concentrations were significantly better maintained.

Adenine↗
PubMedDate not supplied

[The cytobacteriological coloring substance BF (methylene blue and basic fuchsin)].

The Authors have set up a cytobacteriological colouring matter for the reading of the figured elements of liquor, urine, exudats, and trasudats. The colouring solution is steady, it colours and fixes at the same time and is composed by blue methylene and basic fuchsine. There is abready a combination of both colouring matters in WAYSON'S formula for the bipolar colouring matter of the Pasteurella pestis and in PICK'S and Jacobson's formula to point out the intercellular neisserie.

Humans↗
PubMed1975

Photodynamic inactivation of herpesvirus hominins by methylene blue (38524).

Methylene blue, in a concentraion of 10-5M was virostatic in the presence of light but not in the dark for 31 of 37 strains of fresh isolates of herpesvirus hominis. Resistance to the dye developed during treatment. This photodynamic pattern was almost identical to that of neutral red which produced an identical effect. This was not ture for proflavine which was active in the dark in many instances. Cross insensitivity between proflavine and methylene blue was not observed.

Coloring Agents↗
PubMed1976

Photooxidation of methionine with immobilized methylene blue as photooxidizer.

Methylene blue immobilized on porous glass beads was used to catalyze the photooxidation of methionine alone and the methionine residues of lysozyme. A solution of 2 mM methionine in 50% acetic acid was oxidized to methionine sulfoxide in the presence of immobilized methylene blue after 6 h of photooxidation at 37 degrees C. Selective photooxidation of the methionyl residues in lysozyme was achieved after 26 h of reaction in 84% acetic acid at 4 degrees C. The specific activity of lysozyme exposed to light in the presence of methylene blue decreased by 94%, while that of a lysozyme solution in the presence of methylene blue not exposed to light decreased by 21%. The lysozyme solution exposed to light but not containing the methylene blue beads lost 33% of its specific activity after the same period of photooxidation. It was shown that the decrease in enzyme activity was not caused by adsorption of the enzyme onto the beads.

Hydrogen-Ion Concentration↗
PubMed1979

Potential hazard of methylene blue.

The administration of methylene blue to assist the identification of insulin secreting pancreatic adenomata, during surgery in a patient with normal haemoglobin and red cells, was associated with an increase in the methaemoglobin concentration from 0.6% to 7.1%. In patients with unstable haemoglobins or abnormalities of the hexose monophosphate pathway the administration of large amounts of methylene blue is potentially dangerous.

Adenoma↗
PubMed1978

Borax methylene blue: a spectroscopic and staining study.

Borax methylene blue is quite stable at room temperatures of 22-25 C. At 30 C polychroming is slow; during 50 days in a water bath at this temperature the absorption peak moves from 665 to 656 nm. At 35 C, the absorption peak reaches 660 nm in 7 days, 654 nm in 14. At 60 C polychroming is rapid, the absorption peak reaching 640-620 nm in 3 days. When the pH of the borax methylene blue solutions, normally about 9.0, is adjusted to pH 6.5, the absorption peak remains at 665 nm even when incubated at 60 C for extended periods. When used as a blood stain 0.4 ml borax methylene blue (1% methylene blue in 1% borax), 4 ml acetone, 2 ml borax-acid phosphate buffer to bring the solution to pH 6.5, and distilled water to make 40 ml, with 0.2 ml 1% eosin added just before using, an excellent Nocht-Giemsa type stain is achieved after 30 minutes staining. The material plasmodia P. falciparum, P. vivax, and P. berghei stain moderate blue with dark red chromatin and green to black pigment granules. The study confirms Malachowski's 1891 results and explains Gautier's 1896-98 failure to duplicate it.

Borates↗
PubMed1991

Methylene blue prevents hypoxic pulmonary vasoconstriction in cats.

The influence of methylene blue, an inhibitor of soluble guanylate cyclase, on responses to ventilatory and precapillary hypoxia was investigated in the intact-chest cat under conditions of controlled blood flow and constant left atrial pressure. Because methylene blue increased vascular tone, responses to hypoxia were compared when lobar arterial pressure was raised to similar levels with U 46619 and with methylene blue. When lobar arterial pressure was raised with U 46619, ventilation with 7.5% O2 increased lobar arterial pressure significantly. Infusion of methylene blue in concentrations that raised lobar arterial pressure to a value similar to that attained with U 46619 prevented the pressor response to hypoxia, and a significant depressor response was unmasked. The depressor response to hypoxia in the methylene blue-treated animal was not altered by meclofenamate but was blocked by propranolol. A reduction in lobar arterial perfusate PO2 induces an increase in pulmonary vascular resistance in the cat, and this response was prevented by methylene blue. During methylene blue infusion, the vasodilator response to acetylcholine was reduced, whereas the response to isoproterenol was not altered. Although the response to hypoxia was prevented, the pressor response to prostaglandin F2 alpha was not changed. The response to ventilatory hypoxia was enhanced by propranolol or ICI 118551, suggesting that the response is modulated by circulating catecholamines that are probably of adrenal origin. The effects of methylene blue on vascular tone and responses to hypoxia and acetylcholine were reversible, and responses returned to control value after the infusion was terminated.(ABSTRACT TRUNCATED AT 250 WORDS)

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1975

The purification of methylene blue and azure B by solvent extraction and crystallization.

Detailed schemes are described for the preparation of purified methylene blue and azure B from commercial samples of methylene blue. Purified methylene blue is obtained by extracting a solution of the commercial product in an aqueous buffer (pH 9.5) with carbon tetrachloride. Methylene blue remains in the aqueous layer but contaminating dyes pass into the carbon tetrachloride. Metal salt contaminants are removed when the dye is crystallized by the addition of hydrochloric acid at a final concentration of 0.25 N. Purified azure B is obtained by extracting a solution of commercial methylene blue in dilute aqueous sodium hydroxide (pH 11-11.5) with carbon tetrachloride. In this pH range, methylene blue is unstable and yields azure B. The latter passes into the carbon tetrachloride layer as it is formed. Metal salt contaminants remain in the aqueous layer. A concentrated solution oa azure B is obtained by extracting the carbon tetrachloride layer with 4.5 X 10(-4)N hydrobromic acid. The dye is then crystallized by increasing the hydrobromic acid concentration to 0.23 N. Thin-layer chromatography of the purified dyes shows that contamination with related thiazine dyes is absent or negligible. Ash analyses reveal that metal salt contamination is also negligible (sulphated ash less than 0.2%).

Azure Stains↗
PubMed1978

Parathyroid identification by methylene blue infusion.

A preoperative infusion of methylene blue was employed in 20 patients undergoing neck exploration for hyperparathyroidism. The dye was noted to stain adenomas and hyperplastic glands a deep purple-blue colour. Normal parathyroid tissue stained to a lesser extent or not at all. All unstained parathyroid tissue was normal histologically. Methylene blue infusion is a safe method of more rapidly identifying parathyroid tissue. Its preferential staining of abnormal parathyroid tissue can assist the surgeon in deciding the extent of his parathyroid excision.

Adenoma↗
PubMed1976

The composition of stains produced by the oxidation of Methylene Blue.

The composition of some stains produced by the oxidation of Methylene Blue has been studied by thin-layer chromatography. Various named methods for the production of Polychrome Methylene Blue, Azure A, Azure B, Azure C and Methylene Violet Bernthsen have been found to give complex mixtures of varying proportions of up to eleven dyes. Ten of these, namely Methylene Blue, Azure B, Azure A, sym-Dimethylthionine, Azure C, Thionine, Methylene Violet Bernthsen, Methyl Thionoline, Thionoline and Thionol, have been identified by their visible absorption spectra. The remaining dye could not be identified. When used on a laboratory scale, these methods give stains of constant composition independent of the batch of Methylene Blue. Stain composition as revealed in the present study has been compared with that previously indicated by other, less effective, analytical techniques. Reasons are presented why the latter give equivocal results.

Chromatography, Thin Layer↗
PubMed1975

Parathyroid identification by methylene blue infusion.

The intravenous infusion of methylene blue was investigated as a procedure that would identify parathyroid glands during operation in 17 patients with primary hyperparathyroidism. The dye was found to stain all adenomas, most hyperplastic glands and occasionally normal parathyrodi glands. In addition, the frequency of glandular staining was directly related to the size of the gland, although size and histology may have been independent variables. Methylene blue infusion is a safe effective method of localizing abnormal parathyroid glands.

Adenoma↗
PubMed1991

In vivo attenuation of endothelium-dependent pulmonary vasodilation by methylene blue.

In vitro evidence suggests that resting pulmonary vascular tone and endothelium-dependent pulmonary vasodilation are mediated by changes in vascular smooth muscle concentrations of guanosine 3',5'-cyclic monophosphate (cGMP). We investigated this hypothesis in vivo in 19 mechanically ventilated intact lambs by determining the hemodynamic effects of methylene blue (a guanylate cyclase inhibitor) and then by comparing the hemodynamic response to five vasodilators during pulmonary hypertension induced by the infusion of U-46619 (a thromboxane A2 mimic) or methylene blue. Methylene blue caused a significant time-dependent increase in pulmonary arterial pressure. During U-46619 infusions, acetylcholine, ATP-MgCl2, sodium nitroprusside, isoproterenol, and 8-bromo-cGMP decreased pulmonary arterial pressure. During methylene blue infusions, the decreases in pulmonary arterial pressure caused by acetylcholine and ATP-MgCl2 (endothelium-dependent vasodilators) and sodium nitroprusside (an endothelium-independent guanylate cyclase-dependent vasodilator) were attenuated by greater than 50%. The decreases in pulmonary arterial pressure caused by isoproterenol and 8-bromo-cGMP (endothelium-independent vasodilators) were unchanged. This study in intact lambs supports the in vitro evidence that changes in vascular smooth muscle cell concentrations of cGMP in part mediate resting pulmonary vascular tone and endothelium-dependent pulmonary vasodilation.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1978

[Rapid staining of cytologic smears with methylene blue].

It is described a handy staining of cytological smears suitable for out-patients department use. On a dry not fixed smear we put a drop of 0,25% of aqueous solution blue de methylene and we cover it with a cover slide. The smear is stained in a few seconds and the stain remains for half an hour.

Carcinoma, Squamous Cell↗
PubMed1992

Methylene blue inhibits neurogenic cholinergic vasodilator responses in the pulmonary vascular bed of the cat.

The effects of methylene blue, an inhibitor of soluble guanylate cyclase, on pulmonary vasodilator responses to efferent vagal stimulation were investigated in the intact-chest cat under conditions of controlled blood flow and constant left atrial pressure. In animals pretreated with reserpine or phenoxybenzamine, under elevated tone conditions, efferent vagal stimulation at frequencies of 2-16 Hz caused stimulus-frequency-dependent decreases in lobar arterial pressure and pulmonary lobar vascular resistance. The vasodilator response to vagal stimulation was reproducible, blocked by atropine, and reduced by methylene blue. Intralobar infusion of methylene blue increased lobar arterial pressure without significantly altering systemic arterial or left atrial pressure. Methylene blue had no significant effect on vasodilator responses to isoproterenol, albuterol, atriopeptin III, lemakalim, adenosine, ATP, and pituitary adenylate cyclase-activating polypeptide-27 but significantly decreased vasodilator responses to acetylcholine, nitric oxide (NO), sodium nitroprusside, and the S-nitrosothiol, S-nitroso-N-acetyl-penicillamine. The effects of methylene blue on responses to vagal stimulation were reversible and were similar with the addition of a NO synthase inhibitor. The present data suggest that vasodilator responses to cholinergic nerve stimulation involve an increase in the production of guanosine 3',5'-cyclic monophosphate in the pulmonary vascular bed. These results provide additional evidence to support the hypothesis that neurogenically released acetylcholine induces endothelium-dependent, muscarinic, guanylate cyclase-mediated vasodilation.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1978

Lower azure B methylene blue ratios in Giemsa type blood and malaria stains.

Starting from ancient reports that rare samples of methylene blue were apparently sufficiently contaminated with azures to give red plasmodial and red purple nuclear chromatin in Chenzinsky type methylene blue eosin stains, it was decided to determine how little azure B would suffice for such staining in methylene blue eosin stains. The traditional 1902 Giemsa had an azure : methylene blue : eosin ratio of about 6 : 3 : 6.3 : 10; Lillie's 1943 formula had a 5 : 7 : 10 ratio. In the current series of tests 5 : 7 : 10 (I), 4 : 8 : 10 (II), 3 : 9 : 10 (III), 2 : 10 : 10 (IV), 1 : 11 : 10 (V), and 0 : 12 : 10 (VI) were used. Malaria and blood stains were better than the standard 5 : 7 : 10 (I) in III, IV and II in that order. Normal and leukemic human blood, mouse blood with Plasmodium berghei, and monkey blood with the CDC strain of Pl. falciparum were used as test materials. The staining mixtures were made from highly purified samples of azure B and methylene blue. Staining mixtures contained 12 ml 0.1% thiazin dye, 10 ml 0.1% eosin, 2 ml each of glycerol, methanol and 0.1 M phosphate buffer pH 6.5, 3 ml acetone as accelerator, and distilled water to make 40 ml; staining times of 10--30 min were used.

Azure Stains↗
PubMed1976

The effect of storage temperature on the second day methylene-blue test.

The purpose was to show whether or not the methylene-blue test can be postponed to the second day. The milk samples were preserved at three different temperatures 8-10 degrees C, 5-7 degrees C and 2-4 degrees C and the storage time was 16-22 hours. The test indicated that the methylene-blue test could be postponed to the next day satisfying the practical needs if the samples were kept at temperature of 2-4 degrees C. At this temperature the results of the second day methylene-blue test differed statistically not more than p less than 0.05 (nearly significant) from the results of the first day methylene-blue test and the percentage of quality class changes was 2.9.

Animals↗