Journal articles: 'Methaemoglobin'

1

Godwin, I., L. Li, K. Luijben, N. Oelbrandt, J. Velazco, J. Miller, and R. Hegarty. "The effects of chronic nitrate supplementation on erythrocytic methaemoglobin reduction in cattle." Animal Production Science 55, no. 5 (2015): 611. http://dx.doi.org/10.1071/an13366.

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Calcium nitrate and urea were fed as a supplement on an isonitrogenous basis to Angus steers and their erythrocytic methaemoglobin concentrations and NADH- and NADPH-methaemoglobin reductase levels were measured over a 54-day period. Methaemoglobin concentrations remained elevated despite increases in NADH-methaemoglobin reductase activity. In a second experiment, Brahman cross steers were fed either calcium nitrate or urea supplements for 111 days. Blood cells were then taken, washed and exposed to sodium nitrite to convert all haemoglobin to methaemoglobin. The rates of glycolysis and methaemoglobin reduction were measured following incubation of these cells in buffers containing 1, 5 or 10 mM inorganic phosphate. Glucose consumption and methaemoglobin reduction were increased by inorganic phosphate and were more rapid in those animals supplemented with nitrate. Lactate production of erythrocytes was reduced in those animals fed nitrate. It is concluded that adaptation to chronic nitrite exposure occurs in the erythron, resulting in greater methaemoglobin reduction potential and that there is competition between NADH-methaemoglobin reductase and lactate dehydrogenase for NADH.

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Marrs, T. C., J. E. Bright, and R. H. Inns. "Methaemoglobin Production and Reduction by Methylene Blue and the Interaction of Methylene Blue with Sodium Nitrite in vivo." Human Toxicology 8, no. 5 (September 1989): 359–64. http://dx.doi.org/10.1177/096032718900800505.

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Methylene blue, at high concentrations, interferes with the estimation of methaemoglobin using the IL 282 CO-oximeter: the dye does not interfere with the method of Evelyn & Malloy for determination of methaemoglobin. In beagle bitches methylene blue causes both methaemoglobinogenesis and methaemoglobin reduction, the effect of the former being to delay the decline of methaemoglobin levels, when methylene blue is used to reverse the methaemoglobinaemia produced by sodium nitrite.

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Stejskalová, Jana, Pavel Stopka, and Zdeněk Pavlíček. "An ESR study of the peroxidase reaction catalyzed by human methaemoglobin and methaemoglobin-haptoglobin complex." Collection of Czechoslovak Chemical Communications 56, no. 4 (1991): 923–32. http://dx.doi.org/10.1135/cccc19910923.

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The ESR spectra of peroxidase systems of methaemoglobin-ascorbic acid-hydrogen peroxide and methaemoglobin-haptoglobin complex-ascorbic acid-hydrogen peroxide have been measured in the acetate buffer of pH 4.5. For the system with methaemoglobin an asymmetrical signal with g ~ 2 has been observed which is interpreted as the perpendicular region of anisotropic spectrum of superoxide radical. On the other hand, for the system with methaemoglobin-haptoglobin complex the observed signal with g ~ 2 is symmetrical and is interpreted as a signal of delocalized electron. After realization of three repeatedly induced peroxidase processes the ESR signal of the perpendicular part of anisotropic spectrum of superoxide radical is distinctly diminished, whereas the signal of delocalized electron remains practically unchanged. An amino acid analysis of methaemoglobin along with results of the ESR measurements make it possible to derive a hypothesis about the role of haptoglobin in increasing of the peroxidase activity of methaemoglobin.

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Marrs, T. C., R. H. Inns, J. E. Bright, and S. G. Wood. "The Formation of Methaemoglobin by 4-aminopropiophenone (PAPP) and 4-(N-hydroxy) aminopropiophenone." Human & Experimental Toxicology 10, no. 3 (May 1991): 183–88. http://dx.doi.org/10.1177/096032719101000306.

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Oral dosing of rats with the cyanide antidote 4-aminopropiophenone (PAPP), brought about peak methaemoglobin levels at 15-40 min, but peak levels were attained at 15-25 min after intravenous dosing. After both oral and intravenous administration at equimolar doses, 4-(N-hydroxy)aminopropiophenone (PHAPP), the putative methaemoglobin-producing metabolite of PAPP, produced higher peak levels of methaemoglobin than PAPP. Plasma from rats injected with PAPP was capable of forming methaemoglobin when added to naive rat erythrocytes. The identity of the metabolite responsible is discussed.

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5

Benu, I., M. J. Callaghan, N. Tomkins, G. Hepworth, L. A. Fitzpatrick, and A. J. Parker. "The effect of feeding frequency and dose rate of nitrate supplements on blood haemoglobin fractions in Bos indicus cattle fed Flinders grass (Iseilemia spp.) hay." Animal Production Science 56, no. 10 (2016): 1605. http://dx.doi.org/10.1071/an14886.

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Twelve Bos indicus steers (liveweight ± s.d., 317.8 ± 28.5) kg were used in an experiment to examine two factors: daily nitrate dose (0, 30, 40 or 50 g of nitrate/day) and feeding frequency (once or twice a day) on methaemoglobin concentration, daily peak methaemoglobin concentration, rate of incline for methaemoglobin concentration, carboxyhaemoglobin concentration, oxyhaemoglobin concentration, total haemoglobin concentration, haematocrit and dry matter intake of Flinders grass hay. Increasing the dose rate of nitrate increased the fraction of methaemoglobin in the blood of steers (P = 0.014). A highly significant effect was demonstrated for the interaction of dose rate × day (P < 0.001). For once a day intake of nitrate, the dose rates of 40 and 50 g per day showed a greater increase in mean methaemoglobin values than for the 0 and 30 g of nitrate per day. Increasing the dose rate of nitrate also increased the daily peak methaemoglobin fraction and the rate of incline to peak methaemoglobin values for both once and twice a day feeding of the nitrate supplements. However, increasing the dose of nitrate had no significant overall effect on total haemoglobin, deoxyhaemoglobin, carboxyhaemoglobin, haematocrit or dry matter intake. Twice a day feeding of nitrate decreased the formation of methaemoglobin in the blood of Bos indicus steers. This study demonstrates that caution should be exercised when feeding nitrates as a non-protein nitrogen source to cattle grazing low quality pastures in northern Australia.

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Marrs, T. C., and J. E. Bright. "Kinetics of Methaemoglobin Production (1)." Human Toxicology 5, no. 5 (September 1986): 295–301. http://dx.doi.org/10.1177/096032718600500501.

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Methaemoglobin profiles have been studied by using ISIS, a simulation package, and NONLIN, a ion-linear least-squares analysis regression program. A simple kinetic model which satisfactorily describes methaemoglobin profiles after p-aminopropiophenone (PAPP) administration and 4-dimethylaminophenol (DMAP) administration has been developed. The two compounds differed nainly in their effective rates of elimination. The model less satisfactorily described methaemoglobin profiles after p-hydroxyaminopropiophenone (PHAPP) administration.

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7

Wells, Rufus M. G., John Baldwin, and Roger S. Seymour. "Low concentrations of methaemoglobin in marine fishes of the Great Barrier Reef, Australia." Marine and Freshwater Research 48, no. 4 (1997): 303. http://dx.doi.org/10.1071/mf97024.

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Concentrations of methaemoglobin (the oxidized non-functional ferric form of haemoglobin) in the blood of marine fish are poorly documented. Although high concentrations have been reported for fish maintained in captivity, baseline values for wild populations are unknown. Two techniques, the cyanide derivative method and the multiple wavelength method, were used to determine methaemoglobin concentrations in blood samples from 25 species of marine teleosts and elasmobranchs captured on the Australian Great Barrier Reef. Although methaemoglobin generally accounted for less than 2% of total haemoglobin, systematic errors occurred when these two standard methods, developed for mammalian blood, were applied to the blood of some fish species. Most problems arose from reactions of various blood components with the reagents used in the cyanide derivative method. Consequently, the multiple wavelength method generally was more reliable for estimating methaemoglobin in the blood of marine fish. The low methaemoglobin concentrations in fish studied on the Great Barrier Reef indicate high water quality and healthy physiological condition.

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8

Lamont, A. S. M., M. S. Roberts, D. G. Holdsworth, A. Atherton, and J. J. Shepherd. "Relationship between Methaemoglobin Production and Methylene Blue Plasma Concentrations under General Anaesthesia." Anaesthesia and Intensive Care 14, no. 4 (November 1986): 360–64. http://dx.doi.org/10.1177/0310057x8601400406.

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Recently, a family tree with a predisposition for the gene of multiple endocrine neoplasia Type 1 has been identified in Tasmania. As the surgical identification and localisation of parathyroid adenomas is facilitated by the administration of methylene blue, an opportunity has presented to measure the plasma concentration of methylene blue and methaemoglobin production. The study was undertaken to establish whether significant methaemoglobin concentrations were generated during the infusion and whether these concentrations could be related to the corresponding methylene blue concentrations. Mean peak methylene blue concentrations of 3.72 μgl−1, mean percentage methaemoglobin of 10.0 and a Pa.O2 within acceptable clinical ranges were found. No apparent relationship between methylene blue concentration and methaemoglobin production was found.

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9

Chikezie, P. C. "Methaemoglobin Content and NADH-methaemoglobin Reductase Activity of Three Human Erythrocyte Genotypes." Asian Journal of Biochemistry 6, no. 1 (December 15, 2010): 98–103. http://dx.doi.org/10.3923/ajb.2011.98.103.

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10

Langlois, Cynthia J., and Edward J. Calabrese. "The Interactive Effect of Chlorine, Copper and Nitrite on Methaemoglobin Formation in Red Blood Cells of Dorset Sheep." Human & Experimental Toxicology 11, no. 3 (May 1992): 223–28. http://dx.doi.org/10.1177/096032719201100311.

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Simultaneous exposure to chemicals which can oxidize the haemoglobin of the red blood cell to methaemoglobin is common. Although the effects of some of these agents have been documented individually, little research considers the interactive effects. In-vitro experiments on the treated blood of female Dorset sheep assessed the interactive capacity of chlorite, copper and nitrite to affect methaemoglobin formation. All combinations of doses which produced 2.5, 5, 10% methaemoglobin were tested in all possible combinations (a total of 80), as were the controls. This included data on each chemical alone, each two-way combination and the three-way combination. The response is largely additive (the sum of the individual effects) except for one of the two-way interactions, chlorite/nitrite (P < . 01), which showed antagonism. Chlorite may oxidize nitrite which could explain the less-than-additive response. Overall, the result of combining these agents on methaemoglobin was additive.

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11

Teichler, A., T. Standl, A. Diederich, I. Moll, and G. Bruning. "Prilocaine pharmacokinetics and the influence of vitamin C on methaemoglobin concentrations in tumescent anaesthesia." Phlebologie 36, no. 03 (2007): 145–50. http://dx.doi.org/10.1055/s-0037-1622178.

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SummaryIn tumescent local anesthesia high doses of prilocaine are used but valid data on the pharmacokinetics and metabolism of prilocaine during this technique of anesthesia are rare. Patients, methods: In this study plasma prilocaine and methaemoglobin concentrations were measured after subcutaneous injection of prilocaine at doses of 6.69 to 19.21 mg/kg in one hundred patients undergoing varicose vein surgery under tumescent local anesthesia. Half of the patients were randomised to intravenous treatment with 2000 mg ascorbic acid. Glucose-6-phosphate dehydrogenase activity was measured preoperatively. Results: Maximum plasma prilocaine concentrations ranged between 0.14 and 0.86 μg/ml and thus remained below the toxic threshold. Methaemoglobin concentrations ranged between 0.4 and 16.9%. There was no significant effect of vitamin C on the methaemoglobin concentration. Glucose-6-phosphate dehydrogenase activity and methaemoglobin concentrations did not correlate. Conclusions: Tumescent anesthesia with prilocaine at a maximum dose of 20 mg/kg body weight is a safe procedure in varicose vein surgery although the risk of methaemoglobinemia is not reduced by using vitamin C.

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12

Stopka, Pavel, Zdeněk Pavlíček, and Jana Lhotová. "The Peroxidase Reaction of Human Methaemoglobin: Character of the Amino Acid Electrondonor and the Influence of Oxygen." Collection of Czechoslovak Chemical Communications 58, no. 11 (1993): 2715–19. http://dx.doi.org/10.1135/cccc19932715.

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The chemical modification of tyrosyl residues in methaemoglobin led to the decreased peroxidase activity and thus confirmed the role of tyrosyl residues in the catalytic process. The ESR spectra of methaemoglobin modified by tetranitromethane showed on the participation of tyrosine in the generation of superoxide anion radical. After repeated catalytic cycles the rapid decreasing of superoxide anion radical content was observed. This fact indicated, that the generation generation of superoxide anion radical is connected with tyrosyl residue. The residues with high probability are the source of the second electron in the peroxidase reaction the dissolved oxygen in the reaction mixture is necessary. This oxygen is also responsible for tyrosine destruction and thus for the decreasing of peroxidase activity of methaemoglobin.

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13

Harvey, J. W., R. R. King, C. R. Berry, and J. T. Blue. "Methaemoglobin reductase deficiency in dogs." Comparative Haematology International 1, no. 1 (February 1991): 55–59. http://dx.doi.org/10.1007/bf00422695.

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14

Nigam, A., J. Ruddy, and P. E. Robin. "BIPP induced methaemoglobinaemia." Journal of Laryngology & Otology 105, no. 2 (February 1991): 78–79. http://dx.doi.org/10.1017/s0022215100115002.

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AbstractBismuth subnitrate, one of the constituents of BIPP is known to cause methaemoglobinaemia. Ten patients had blood estimations for methaemoglobin levels before and after nasal packing with BIPP impregnated gauze. Only one patient exhibited abnormal levels of methaemoglobin and this was most probably the result of the large quantity of BIPP used. It is unlikely that significant methaemoglobinaemia occurs during the routine use of BIPP in the nose.

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15

SG, Christian. "Effect of Smoke Inhalation on Methaemoglobin, Oxyhaemoglobin and Packed Cell Volume of Plantain (“Bole”) Roasters in Port- Harcourt, Nigeria." Haematology International Journal 6, no. 1 (2022): 1–4. http://dx.doi.org/10.23880/hij-16000196.

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Bole is a popular delicacy in Port Harcourt, Nigeria. Bole is roast plantain, roasted above burning charcoal. It is usually roasted alongside yam, and fish. In the course of roasting Bole, women are exposed to smoke which in the long run may produce some effects on the blood. The study examines how the smoke inhaled by these women affects their packed cell volume, methaemoglobin and oxyhaemoglobin levels. This study was carried out on blood samples collected from women who roast Bole (test subjects), in Port Harcourt, specifically in Diobu and Borikiri area. Control subjects were apparently healthy women that were not exposed to smoke. A total of 40 samples (20 from test subjects and 20 from control subjects) were collected through standard vein-puncture technique. Packed cell volume was determined using microhaematocrit method, oxyhaemoglobin and methaemoglobin levels were analyzed using spectrophotometric method. Methaemoglobin level (4.94 ± 4.17%) and PCV level of the test subjects (39.45 ± 1.32%) were significantly greater than that of control subjects (methaemoglobin: 1.64 ± 0.39%) and (packed cell volume: 38.50 ± 1.40%); (p-value = 0.00114 and 0.032887 for methaemoglobin and PCV respectively). The Oxyhaemoglobin levels of test subjects (11.38 ± 1.29g/dl) was significantly lower than the oxyhaemoglobin level of the control subjects (15.39 ± 0.89g/dl); (p- value = 0.000). The study therefore reveals that exposure to smoke increases methemoglobin levels and decreases oxyhaemoglobin level; this does not support adequate physiological oxygen delivery to body tissues and organs and could lead to hypoxia. We therefore recommended that these women use other means which produces less smoke to roast their plantain (bole), increase hydration, and make use of nose masks to reduce smoke inhalation.

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16

Huntington, GR, and JM Pennington. "Fatal Methaemoglobinaemia Due To Intentional Sodium Nitrite Poisoning." Acute Medicine Journal 20, no. 2 (April 1, 2021): 148–50. http://dx.doi.org/10.52964/amja.0856.

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We report a case of fatal methaemoglobinaema resulting from sodium nitrite poisoning. A 28 year old woman arrested in the emergency department following collapse. During resuscitation a venous blood gas revealed a methaemoglobin percentage of 81%. Following treatment with methylene blue, sodium bicarbonate and adrenaline, the methaemoglobin decreased. Prior to transfer to intensive care, a CT head revealed extensive hypoxic brain injury. Two days later brain death was confirmed on brainstem testing. Severe methaemoglobinaemia is rapidly fatal, with fast diagnosis and treatment associated with improved outcomes.

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Müller, J., K. Murawski, Z. Szymanowska, A. Koziorowski, and L. Radwan. "Hereditary Deficiency of NADPH2-Methaemoglobin Reductase." Acta Medica Scandinavica 173, no. 2 (April 24, 2009): 243–47. http://dx.doi.org/10.1111/j.0954-6820.1963.tb16529.x.

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Ogawa, E., S. S. Billiards, J. M. King, and N. S. Agar. "Methaemoglobin Formation in Euros and Bettong." Comparative Haematology International 10, no. 4 (June 1, 2001): 196–99. http://dx.doi.org/10.1007/s005800170004.

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Behera, G. C., S. K. Behera, R. K. Jena, and V. S. Bharati. "Study of Methaemoglobin in Malaria Patients." Indian Journal of Hematology and Blood Transfusion 32, no. 1 (March 24, 2015): 100–103. http://dx.doi.org/10.1007/s12288-015-0522-5.

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Frøslie, Arne. "Methaemoglobin Reduction and NADH-Dependent Methaemoglobin Reductase Activity Following DNBP- and Nitrite Induced Methaemoglobinemia in Sheep." Acta Pharmacologica et Toxicologica 38, no. 1 (March 13, 2009): 17–23. http://dx.doi.org/10.1111/j.1600-0773.1976.tb03094.x.

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Cowled, Brendan D., Peter Elsworth, and Steven J. Lapidge. "Additional toxins for feral pig (Sus scrofa) control: identifying and testing Achilles' heels." Wildlife Research 35, no. 7 (2008): 651. http://dx.doi.org/10.1071/wr07072.

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A literature review was conducted in order to identify unique weaknesses in the physiology or metabolism of pigs that could be targeted with specific chemicals (i.e. an ‘Achilles’ heel’ search). A promising weakness identified was the species’ susceptibility to methaemoglobin-forming compounds, most likely related to their uniquely low levels of methaemoglobin reductase. Further examination revealed that sodium nitrite is a cost-effective, readily available methaemoglobin-forming compound that is highly toxic to domestic pigs, which has caused numerous accidental poisonings. Pen trials on pigs showed that sodium nitrite delivered by gavage (>90 mg kg−1) and freely consumed in bait (>400 mg kg−1) caused rapid and lethal rises in methaemoglobin. Sodium nitrite appeared to be more humane than currently used toxins, with deaths following bait consumption being considerably quicker and with fewer symptoms (within 80 min of clinical signs beginning; clinical signs including infrequent vomiting, lethargy, ataxia and dyspnoea). The review also identified a second deficiency in the metabolism of pigs, namely high sensitivity to selective inhibition of cytochrome P450 liver enzymes. This leads to potentially lethal interactions between various drugs, such as two antibiotics, monensin and tiamulin. A pen trial confirmed that the antibiotic combination in a single gavage dose was reliably and rapidly lethal to pigs. However, its utility as a pig toxin is low, because it was unpalatable to pigs when delivered in bait and appeared to cause pain and suffering (leading to the early termination of pen trials). The findings presented here demonstrate the potential of sodium nitrite as an additional feral pig toxin.

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22

Williams, Harry, Paul Hayter, Divyashree Ravishankar, Anthony Baines, Harry Layfield, Lorraine Croucher, Catherine Wark, Andrew Bicknell, Steven Trim, and Sakthivel Vaiyapuri. "Impact of Naja nigricollis Venom on the Production of Methaemoglobin." Toxins 10, no. 12 (December 15, 2018): 539. http://dx.doi.org/10.3390/toxins10120539.

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Snakebite envenomation is an affliction currently estimated to be killing upwards of 100,000 people annually. Snakebite is associated with a diverse pathophysiology due to the magnitude of variation in venom composition that is observed worldwide. The haemolytic (i.e., lysis of red blood cells) actions of snake venoms are well documented, although the direct impact of venoms on haemoglobin is not fully understood. Here we report on the varied ability of a multitude of snake venoms to oxidise haemoglobin into methaemoglobin. Moreover, our results demonstrate that the venom of an elapid, the black necked spitting cobra, Naja nigricollis, oxidises oxyhaemoglobin (Fe2+) into methaemoglobin (Fe3+) in a time- and concentration-dependent manner that is unparalleled within the 47 viper and elapid venoms evaluated. The treatment of venom with a reducing agent, dithiothreitol (DTT) is observed to potentiate this effect at higher concentrations, and the use of denatured venom demonstrates that this effect is dependent upon the heat-sensitive proteinaceous elements of the venom. Together, our results suggest that Naja nigricollis venom appears to promote methaemoglobin production to a degree that is rare within the Elapidae family, and this activity appears to be independent of proteolytic activities of venom components on haemoglobin.

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23

Beutler, Ernest, and Zeola Collins. "Methaemoglobin Reduction: Studies Using Galactose as Substrate." Scandinavian Journal of Haematology 2, no. 4 (April 24, 2009): 343–54. http://dx.doi.org/10.1111/j.1600-0609.1965.tb01310.x.

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Hänscheid, Thomas, Tom Gresnigt, Sascha Löhr, Arnaud Flamen, Thomas Zoller, José Melo-Cristino, and Martin P. Grobusch. "Methaemoglobin and COHb in patients with malaria." Malaria Journal 13, no. 1 (2014): 285. http://dx.doi.org/10.1186/1475-2875-13-285.

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25

Cataldo, Franco. "On the action of ozone on methaemoglobin." Polymer Degradation and Stability 86, no. 3 (December 2004): 473–81. http://dx.doi.org/10.1016/j.polymdegradstab.2004.05.020.

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Verhaert, L. L. W. "Methaemoglobinemia Induced by MDMA?" Case Reports in Pulmonology 2011 (2011): 1–3. http://dx.doi.org/10.1155/2011/494328.

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Case. A 45-year-old man with a blank medical history presented at the emergency room with dizziness and cyanosis. Physical examination showed cyanosis with a peripheral saturation (SpO2) of 85%, he did not respond to supplemental oxygen. Arterial blood gas analysis showed a striking chocolate brown colour. Based on these data, we determined the arterial methaemoglobin concentration. This was 32%. We gave 100% oxygen and observed the patient in a medium care unit. The next day, patient could be discharged in good condition. Further inquiry about exhibitions and extensive history revealed that the patient used MDMA (3,4- methylenedioxymethamphetamine, the active ingredient of ecstasy).Conclusion. Acquired methaemoglobinemia is a condition that occurs infrequently, but is potentially life threatening. Different nutrients, medications, and chemicals can induce methaemoglobinemia by oxidation of haemoglobin. The clinical presentation of a patient with methaemoglobinemia is due to the impossibility of O2binding and transport, resulting in tissue hypoxia. Important is to think about methaemoglobin in a patient who presents with cyanosis, a peripheral saturation of 85% that fails to respond properly to the administration of O2. Because methaemoglobin can be reduced physiologically, it is usually sufficient to remove the causative agent, to give O2, and to observe the patient.

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Dunne, Jacqueline, Alexis Caron, Patrick Menu, Abdu I. Alayash, Paul W. Buehler, Michael T. Wilson, Radu Silaghi-Dumitrescu, Beatrice Faivre, and Chris E. Cooper. "Ascorbate removes key precursors to oxidative damage by cell-free haemoglobin in vitro and in vivo." Biochemical Journal 399, no. 3 (October 13, 2006): 513–24. http://dx.doi.org/10.1042/bj20060341.

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Haemoglobin initiates free radical chemistry. In particular, the interactions of peroxides with the ferric (met) species of haemoglobin generate two strong oxidants: ferryl iron and a protein-bound free radical. We have studied the endogenous defences to this reactive chemistry in a rabbit model following 20% exchange transfusion with cell-free haemoglobin stabilized in tetrameric form [via cross-linking with bis-(3,5-dibromosalicyl)fumarate]. The transfusate contained 95% oxyhaemoglobin, 5% methaemoglobin and 25 μM free iron. EPR spectroscopy revealed that the free iron in the transfusate was rendered redox inactive by rapid binding to transferrin. Methaemoglobin was reduced to oxyhaemoglobin by a slower process (t1/2=1 h). No globin-bound free radicals were detected in the plasma. These redox defences could be fully attributed to a novel multifunctional role of plasma ascorbate in removing key precursors of oxidative damage. Ascorbate is able to effectively reduce plasma methaemoglobin, ferryl haemoglobin and globin radicals. The ascorbyl free radicals formed are efficiently re-reduced by the erythrocyte membrane-bound reductase (which itself uses intra-erythrocyte ascorbate as an electron donor). As well as relating to the toxicity of haemoglobin-based oxygen carriers, these findings have implications for situations where haem proteins exist outside the protective cell environment, e.g. haemolytic anaemias, subarachnoid haemorrhage, rhabdomyolysis.

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Shpaizer, Adi, Joseph Kanner, and Oren Tirosh. "S-Nitroso-N-acetylcysteine (NAC–SNO) vs. nitrite as an anti-clostridial additive for meat products." Food & Function 12, no. 5 (2021): 2012–19. http://dx.doi.org/10.1039/d0fo02839h.

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NAC–SNO is an efficient preservative against Clostridium spore germination, and under the same conditions and concentrations generates much less methaemoglobin and detectable N-nitrosoamines in the blood, in vivo.

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Kurian, Simi, Nalinikanta Panigrahy, Vijayanand Jamalpuri, and Dinesh Chirla. "Cow’s milk protein allergy in a neonate presenting with methaemoglobinaemia." BMJ Case Reports 15, no. 8 (August 2022): e246599. http://dx.doi.org/10.1136/bcr-2021-246599.

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Cow’s milk protein allergy (CMPA) is the most common food allergy in infants. A previously healthy neonate fed with infant formula presented diarrhoea, vomiting and respiratory distress with cyanosis. Investigations showed thrombocytosis and leucocytosis with lymphocyte predominance. To our surprise blood gas analysis showed metabolic acidosis and a high methaemoglobin level of 33% (normal range <3%). Clinical status, metabolic acidosis and methaemoglobin level returned to normal following fluid resuscitation and methylene blue administration. The neonate was later managed with breast feeding and elemental formula. CMPA was diagnosed based on history and clinical improvement after elemental formula. Although not common in CMPA, methaemoglobinaemia should be recognised as a differential diagnosis in a hypoxic infant with metabolic acidosis and diarrhoea as early recognition and treatment with methylene blue can save a child’s life.

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SMALLEY, John W., Andrew J. BIRSS, Robert WITHNALL, and Jack SILVER. "Interactions of Porphyromonas gingivalis with oxyhaemoglobin and deoxyhaemoglobin." Biochemical Journal 362, no. 2 (February 22, 2002): 239–45. http://dx.doi.org/10.1042/bj3620239.

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When grown on blood-containing solid media, the anaerobic periodontal pathogen Porphyromonas gingivalis produces a haem pigment, the major component of which is the μ-oxo bishaem of iron protoporphyrin IX [Smalley, Silver, Marsh and Birss (1998) Biochem. J. 331, 681–685]. In this study, μ-oxo bishaem generation by P. gingivalis from oxy- and deoxyhaemoglobin was examined. Bacterial cells were shown to convert oxyhaemoglobin into methaemoglobin, which was degraded progressively, generating a mixture of both monomeric and μ-oxo dimeric iron protoporphyrin IX. The rate of methaemoglobin formation was accelerated in the presence of bacterial cells, but was inhibited by N-ethylmaleimide and tosyl-lysylchloromethylketone. Interaction of cells with deoxyhaemoglobin resulted in formation of an iron(III) haem species (Soret λmax, 393nm), identified as pure μ-oxo bishaem.

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Puppo, A., and B. Halliwell. "Formation of hydroxyl radicals from hydrogen peroxide in the presence of iron. Is haemoglobin a biological Fenton reagent?" Biochemical Journal 249, no. 1 (January 1, 1988): 185–90. http://dx.doi.org/10.1042/bj2490185.

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The ability of oxyhaemoglobin and methaemoglobin to generate hydroxyl radicals (OH.) from H2O2 has been investigated using deoxyribose and phenylalanine as ‘detector molecules’ for OH.. An excess of H2O2 degrades methaemoglobin, releasing iron ions that react with H2O2 to form a species that appears to be OH.. Oxyhaemoglobin reacts with low concentrations of H2O2 to form a ‘reactive species’ that degrades deoxyribose but does not hydroxylate phenylalanine. This ‘reactive species’ is less amenable to scavenging by certain scavengers (salicylate, phenylalanine, arginine) than is OH., but it appears more reactive than OH. is to others (Hepes, urea). The ability of haemoglobin to generate not only this ‘reactive species’, but also OH. in the presence of H2O2 may account for the damaging effects of free haemoglobin in the brain, the eye, and at sites of inflammation.

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Akintonwa, D. A. A. "Theoretical mechanistic basis of oxidants of methaemoglobin formation." Medical Hypotheses 54, no. 2 (February 2000): 312–20. http://dx.doi.org/10.1054/mehy.1999.0838.

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Ogawa, E., S. S. O’Callaghan, and N. S. Agar. "Methaemoglobin formation in the koala and the possum." Comparative Haematology International 8, no. 3 (September 1998): 171–73. http://dx.doi.org/10.1007/bf02642509.

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Park, K. S., M. J. Kim, J. S. Ho, C. K. Ryu, and J. H. Chung. "Effect of Glutathione Depletion on Haemoglobin and Membrane Integrity of Red Blood Cells of Rats." Journal of International Medical Research 24, no. 1 (January 1996): 40–46. http://dx.doi.org/10.1177/030006059602400106.

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The effects of streptozocin (streptozotocin) and water-soluble menadione (menadione bisulphite, sodium salt) on the haemoglobin content and membrane integrity of red blood cells were investigated. Both menadione bisulphite and streptozocin significantly depleted glutathione but menadione bisulphite was much more effective in reducing glutathione than was streptozocin. Menadione bisulphite, at concentrations above 0.1 mM, caused substantial conversion of oxygenated haemoglobin into methaemoglobin while streptozocin did not alter the haemoglobin content of the red blood cells at concentrations of up to 100 mM. Both agents demonstrated only a modest ability to haemolyse the red blood cells, even at concentrations up to 300 mM. These results suggest that depletion of glutathione by menadione causes the conversion of oxyhaemoglobin to methaemoglobin. In contrast, streptozocin-induced glutathione depletion does not seem to be well correlated with alterations in haemoglobin content.

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Tang, Andy Sing Ong, Kok Choon Cheah, Tze Shin Leong, and Lee Ping Chew. "Methaemoglobinaemia in pregnancy: Real world experience in a single centre in Malaysia." Proceedings of Singapore Healthcare 31 (June 2022): 201010582211115. http://dx.doi.org/10.1177/20101058221111575.

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The literature on methaemoglobinaemia in pregnancy is scarce, imposing clinical challenges to both obstetricians and haematologists. We report a total of nine pregnancies with methaemoglobinaemia treated in our centre. Their methaemoglobin levels, mode of delivery, pregnancy management and outcome were summarized.

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Lewis, Justin S., and Zachary G. Jacobs. "Subtle case of dapsone-induced methaemoglobinaemia." BMJ Case Reports 13, no. 8 (August 2020): e235403. http://dx.doi.org/10.1136/bcr-2020-235403.

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Methaemoglobinaemia is a rare disease that is typically caused by a medication or other exogenous agent, with dapsone being the most common. It occurs when the concentration of methaemoglobin rises via ferrous haeme irons becoming oxidised to the ferric state, which shifts the oxygen dissociation curve to the left. The net result of an elevated methaemoglobin concentration is functional anaemia and impaired oxygen delivery to tissues. At lower blood levels, this can cause symptoms such as cyanosis, lethargy, headache and fatigue, whereas at higher levels it can be fatal. Here we discuss a subtle case of dapsone-induced methaemoglobinaemia presenting as subacute mental status changes and apparent hypoxia, thus highlighting the association between methaemoglobinaemia and dapsone. This case demonstrates the importance of thorough medication reconciliation and maintaining a broad differential diagnosis, while also recognising the significance of conflicting data and their implications for the workup.

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Vandegriff, Kim D., Ashok Malavalli, Charles Minn, Eva Jiang, Jeff Lohman, Mark A. Young, Michele Samaja, and Robert M. Winslow. "Oxidation and haem loss kinetics of poly(ethylene glycol)-conjugated haemoglobin (MP4): dissociation between in vitro and in vivo oxidation rates." Biochemical Journal 399, no. 3 (October 13, 2006): 463–71. http://dx.doi.org/10.1042/bj20060809.

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Haemoglobin-based oxygen carriers can undergo oxidation of ferrous haemoglobin into a non-functional ferric form with enhanced rates of haem loss. A recently developed human haemoglobin conjugated to maleimide-activated poly(ethylene glycol), termed MP4, has unique physicochemical properties (increased molecular radius, high oxygen affinity and low cooperativity) and lacks the typical hypertensive response observed with most cell-free haemoglobin solutions. The rate of in vitro MP4 autoxidation is higher compared with the rate for unmodified SFHb (stroma-free haemoglobin), both at room temperature (20–22 °C) and at 37 °C (P<0.001). This appears to be attributable to residual catalase activity in SFHb but not MP4. In contrast, MP4 and SFHb showed the same susceptibility to oxidation by reactive oxygen species generated by a xanthine–xanthine oxidase system. Once fully oxidized to methaemoglobin, the rate of in vitro haem loss was five times higher in MP4 compared with SFHb in the fast phase, which we assign to the β subunits, whereas the slow phase (i.e. haem loss from α chains) showed similar rates for the two haemoglobins. Formation of MP4 methaemoglobin in vivo following transfusion in rats and humans was slower than predicted by its first-order in vitro autoxidation rate, and there was no appreciable accumulation of MP4 methaemoglobin in plasma before disappearing from the circulation. These results show that MP4 oxidation and haem loss characteristics observed in vitro provide information regarding the effect of poly(ethylene glycol) conjugation on the stability of the haemoglobin molecule, but do not correspond to the oxidation behaviour of MP4 in vivo.

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Cheyney, Sarah, Zachary Field, Jacqueline Kropf, and Steve Carlan. "Methaemoglobinaemia from Vagisil creme in a 50-year-old woman." BMJ Case Reports 14, no. 3 (March 2021): e239697. http://dx.doi.org/10.1136/bcr-2020-239697.

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Methaemoglobinaemia is a life-threatening condition that results from increased methaemoglobin production. As methaemoglobin is unable to reversibly bind to oxygen potentially lethal hypoxia and functional anaemia can occur. Benzocaine can be used as a topical anaesthetic and can be found in many nonprescription preparations marketed for self-application. It is known to cause methaemoglobinaemia in rare cases but most reports describe the complication occurring during endoscopy procedures. Methaemoglobinaemia occurring after topical benzocaine use on the perineum of a perimenopausal woman is exceedingly rare. A 50-year-old woman with methaemoglobinaemia secondary to the perineal application of over-the counter Vagisil (benzocaine 20% and resorcinol 3%- an antiseptic and disinfectant, respectively) presented to the emergency department. She had been using Vagisil for severe, chronic vaginal itching. While methaemoglobinaemia secondary to excessive use of over-the-counter medications such as Vagisil creme is exceedingly rare, it should be included in the differential diagnosis.

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Cooper, C. E., N. B. J. Vollaard, T. Choueiri, and M. T. Wilson. "Exercise, free radicals and oxidative stress." Biochemical Society Transactions 30, no. 2 (April 1, 2002): 280–85. http://dx.doi.org/10.1042/bst0300280.

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This article reviews the role of free radicals in causing oxidative stress during exercise. High intensity exercise induces oxidative stress and although there is no evidence that this affects sporting performance in the short term, it may have longer term health consequences. The mechanisms of exercise-induced oxidative stress are not well understood. Mitochondria are sometimes considered to be the main source of free radicals, but in vitro studies suggest they may play a more minor role than was first thought. There is a growing acceptance of the importance of haem proteins in inducing oxidative stress. The release of metmyoglobin from damaged muscle is known to cause renal failure in exercise rhabdomyolysis. Furthermore, levels of methaemoglobin increase during high intensity exercise, while levels of antioxidants, such as reduced glutathione, decrease. We suggest that the free-radical-mediated damage caused by the interaction of metmyoglobin and methaemoglobin with peroxides may be an important source of oxidative stress during exercise.

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Christian, Serekara Gideon, Orokwu Eziaku Chukuigwe-Igbere, Ransom Baribefii Jacob, and Happiness Nkiruka Ejimmadu. "Effect of Soot Inhalation on Methaemoglobin and Oxyhaemoglobin Levels of some Residents of Iwofe, Port Harcourt Rivers state, Nigeria." Sokoto Journal of Medical Laboratory Science 7, no. 1 (June 10, 2022): 61–67. http://dx.doi.org/10.4314/sokjmls.v7i1.8.

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Soot is a mass of impure particles of carbon obtained from incomplete hydrocarbon combustion. Soot is an ultrafine air-borne pollutant and enters into the body through ingestion, skin contact and inhalation causing devastating effects on the blood cells. The aim of the study was to determine the effect of soot inhalation on methaemoglobin and oxyhaemoglobin levels of individuals resident in both Iwofe, Port Harcourt (exposed subjects) and Ihiala, Anambra state (control subjects). The study is a case control study involving residents of Iwofe, Rumuolumeni, who have been exposed to soot pollution in the environment for an average period of one year. Iwofe is in Port Harcourt, the capital of Rivers State, Nigeria. A total of fifty (50) test samples were obtained. Thirty control samples were obtained from subjects in Ihiala a city located in the South of Anambra state where illegal oil refineries and other major means of soot generation are not as comparable to what is present in Port Harcourt and its environs. Methaemoglobin and Oxyhaemoglobin concentrations were analyzed using spectrophotometric method. The data obtained was analyzed using SPSS for descriptive statistics (mean and standard deviations) and inferential statistics (t-test). The student t-test was used to test for difference in the methaemoglobin and oxyhaemoglobin levels between the exposed subjects and non-exposed controls and based on age groups and gender. An error of probability (p ≤ 0.05) is considered levels of exposed subjects showing the effect of soot inhalation. Activities of illegal oil refineries (a major source of soot pollution in the city) should be stopped along with other activities like burning of tyres, indiscriminate burning of wastes and gas flaring etc.

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Silvério, Alessandra Cristina Pupin, Simone Caetani Machado, Vanessa Caroline Cardoso Silva, Estéfane Rodrigues, and Isarita Martins. "Determination of carboxyhaemoglobin and methaemoglobin levels in donated blood." Research, Society and Development 10, no. 10 (August 11, 2021): e294101018859. http://dx.doi.org/10.33448/rsd-v10i10.18859.

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To determine the percentages of carboxyhaemoglobin (COHb) and methaemoglobin (MeHb) in donor blood and to compare these levels between smokers and nonsmokers at different time points during blood storage. Blood donors were recruited from Haematology Service, University Hospital Alzira Velano, Alfenas-MG. The blood was kept in collecting ducts (noodles) containing citrate, phosphate and dextrose (CPD) and stored at 4°C throughout the storage period. Since the noodles kept the characteristics of the bags, COHb and MeHb levels were analysed on the day of donation and after 20 days of storage. Levels of COHb and MeHb were determined using spectrophotometric methods. Non-parametric Friedman and Mann-Whitney tests were employed to compare COHb and MeHb levels before and after the storage and groups of smokers and nonsmokers, respectively. Levels of COHb and MeHb in the blood collected from smokers and nonsmokers were statistically different (p< 0.05; Mann- Whitney test) when the samples were analyzed before the storage. In blood of smokers, COHb levels were no different over a 20-day storage period (p= 0.7009; Friedman test). On the other hand, MeHb levels were significant different over a 20-day storage period (p< 0.05). The results suggest the need to regularly assess COHb and MeHb levels in donor blood stored in blood banks.

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Coleman, Michael D., Helen L. Tolley, and Amisha K. Desai. "Monitoring antioxidant effects using methaemoglobin formation in diabetic erythrocytes †." British Journal of Diabetes & Vascular Disease 1, no. 1 (August 2001): 88–92. http://dx.doi.org/10.1177/14746514010010011601.

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Frøslie, Arne. "Methaemoglobin Formation by Diamino Metabolites of DNOC and DNBP." Acta Pharmacologica et Toxicologica 32, no. 3-4 (March 13, 2009): 257–65. http://dx.doi.org/10.1111/j.1600-0773.1973.tb01469.x.

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44

Meyding-Lamad�, U., M. Forsting, F. Albert, S. Kunze, and K. Sartor. "Accelerated methaemoglobin formation: potential pitfall in early postoperative MRI." Neuroradiology 35, no. 3 (1993): 178–80. http://dx.doi.org/10.1007/bf00588487.

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Kinsella, JohnP, and StevenH Abman. "Methaemoglobin during nitric oxide therapy with high-frequency ventilation." Lancet 342, no. 8871 (September 1993): 615. http://dx.doi.org/10.1016/0140-6736(93)91439-s.

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46

Heales, Simon J. R., and Janet Bennett. "The determination of methaemoglobin levels by first derivative spectroscopy." Clinica Chimica Acta 153, no. 3 (December 1985): 253–57. http://dx.doi.org/10.1016/0009-8981(85)90360-2.

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Memis, D., B. Karamanlioglu, M. Yuksel, I. Gemlik, and Z. Pamukcu. "The Influence of Methylene Blue Infusion on Cytokine Levels during Severe Sepsis." Anaesthesia and Intensive Care 30, no. 6 (December 2002): 755–62. http://dx.doi.org/10.1177/0310057x0203000606.

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The aim of our study was to assess the effect of methylene blue infusion on plasma levels of cytokines in severe sepsis. In a prospective, randomized, double-blind, placebo-controlled study, patients received either methylene blue 0.5 mg.kg -1 .h -1 (MB group, n=15) or similar volume of isotonic saline (control group, n=15) IV for 6 hours. Plasma concentrations of tumour necrosis factor-α, interleukin-1, interleukin-2 receptor, interleukin-6, interleukin-8 were measured by sensitive immunoassays at basal (15 min before start of the study), immediately after, and at 24 and 48 hours after methylene blue infusion. We evaluated haemodynamic parameters (mean arterial pressure, heart rate), blood gases, methaemoglobin levels, and biochemical parameters at the same time. Methylene blue administration had no significant effect on plasma cytokine levels, blood gases and biochemical parameters. When compared to placebo infusion in controls, methylene blue administration resulted in significantly higher mean arterial pressure (85±14 mmHg vs 74.1±10.3 mmHg; P<0.01), and methaemoglobin levels (1.06±0.22% vs 0.9±0.05%; P<0.05). Furthermore, comparison with baseline levels revealed significantly increased both mean arterial pressure (85±14 mmHg and 74.1±10.2 mmHg; P<0.05) and methaemoglobin levels (1.06±0.22% and 0.88±0.06%; P<0.05) in MB group. There was no difference in mortality rates between the groups. We found that methylene blue infusion did not change cytokine levels or outcome in severe sepsis. The administration of methylene blue, however, resulted in a transient increase in arterial pressure. Because of the limited size of the present study, and the short period of observation, our findings need to be confirmed by larger clinical trials of methylene blue infused in a dose-titrated manner.

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Doblander, C., and R. Lackner. "Oxidation of nitrite to nitrate in isolated erythrocytes: a possible mechanism for adaptation to environmental nitrite." Canadian Journal of Fisheries and Aquatic Sciences 54, no. 1 (January 1, 1997): 157–61. http://dx.doi.org/10.1139/f96-254.

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Rainbow trout (Oncorhynchus mykiss) were exposed to nitrite (0.007 mmol NO2- · L-1) for 48 days. During the first 14 days, the methaemoglobin concentration in the blood as well as the NO2- and NO3- concentrations in the plasma increased whereas further days of exposure led to a decrease in the nitrite, nitrate, and methaemoglobin concentrations in the blood. Isolated erythrocytes from rainbow trout have the ability to detoxify nitrite by oxidation to nitrate, thus removing this compound from the blood. This process is dependent on oxygen loading of haemoglobin and on the nitrite concentration in the medium. In anoxic erythrocytes the oxidation of nitrite to nitrate is drastically reduced. Assuming Michaelis-Menten kinetics, the uptake for nitrite in our investigation was estimated between 1.06 and 2.21 µmol NO2- · h-1 · kg fish-1. After 14 days of exposure approximately 20% of the total NO2- taken up will be detoxified by erythrocytes in fish. We hypothesize that rainbow trout have the capacity for adapting to nitrite exposure by increasing the rate of oxidation to nitrate.

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Meulenbelt, J., J. A. M. A. Dormans, M. Marra, P. J. A. Rombout, and B. Sangster. "Rat Model to Investigate the Treatment of Acute Nitrogen Dioxide Intoxication." Human & Experimental Toxicology 11, no. 3 (May 1992): 179–87. http://dx.doi.org/10.1177/096032719201100306.

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1 The pulmonary toxic events induced by acute nitrogen dioxide (NO)2 exposure were studied in the rat to develop an inhalation model to investigate therapeutic measures. 2 A good correlation was observed between the lung weights and severity of the atypical pneumonitis. The pulmonary effects observed, became more pronounced with increasing NO 2 concentrations (0, 25, 75, 125, 175 or 200 ppm, 1 ppm NO2=1.88 mg m-3 NO2) and exposure times (5, 10, 20 or 30 min). 3 An adequate NO 2 concentration is 175 ppm, because it can induce a severe lung injury without mortality. This makes it possible to investigate suitable therapeutic interventions for several days. 4 Following acute inhalatory NO2 intoxication, transformation of NO2 to nitrate is presumably more notable than transformation to nitrite. 5 The transformation of NO2 to nitrate in lung tissue causes a slight increase in the serum nitrite concentration, which does not induce measurable formation of methaemoglobin. 6 Presumably, methaemoglobin does not contribute to the toxicity of NO2 intoxication.

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Bright, J. E., and T. C. Marrs. "Effect of p-aminopropiophenone (PAPP), a cyanide antidote, on cyanide given by intravenous infusion." Human Toxicology 6, no. 2 (March 1987): 133–37. http://dx.doi.org/10.1177/096032718700600205.

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1 Beagle bitches were infused with potassium cyanide solution after protection with p-aminopropiophenone (PAPP). 2 Methaemoglobin levels fell very rapidly after the start of the infusion. 3 Whole blood and plasma cyanide estimations revealed that most of the cyanide was sequestered inside the red cells. 4 Animals survived a supralethal dose of cyanide when protected with PAPP.

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Journal articles on the topic 'Methaemoglobin'

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