Investigations into the effect of carbon monoxide exposure on bloodstain color: Implications for the Shroud of Turin
نویسنده
چکیده
Hemoglobin (Hb) is the major protein present in red blood cells whose function is to transport oxygen throughout the body. The oxygenated form of hemoglobin is responsible for the typical red color of fresh blood that is normally observed. Carbon monoxide (CO) binds to hemoglobin with an affinity 250-300 times greater than that of oxygen, making it a highly competitive, toxic substance which can be lethal at even relatively limited levels of exposure. Blood drawn from patients experiencing CO poisoning exhibits a “cherry red” appearance, which is often useful in the initial diagnosis. CO levels from such patients have been reported to persist in refrigerated sealed liquid blood samples stored in the presence of preservatives for at least three years; however, no data exists regarding the persistence of CO in aged, dried bloodstains. It has been noted that the bloodstains on the Shroud of Turin appear too red in color for blood that is reportedly some 600-2000 years old. Various explanations have been put forth for the blood color on the Shroud, including the suggestion that CO bound to hemoglobin via endogenous or exogenous mechanisms is responsible. In this report, the effect of CO exposure on bloodstain color is evaluated and its relevance to the appearance of the Shroud of Turin bloodstains is discussed. Introduction Fresh oxygenated blood is bright red in appearance, which upon drying changes into a dark brownish color within approximately 12-24 hours. The molecular basis for the color change in drying blood is well established. When hemoglobin molecules present in red blood cells contain bound oxygen (Hb-O2), the blood maintains its red color. During the drying process and exposure to air, hemoglobin becomes deoxygenated, and converts to methemoglobin (Hb-Met), giving bloodstains a brownish, black appearance (1-3). The methemoglobin form of hemoglobin is unable to bind oxygen, and is referred to as the oxidized form. Oxidation of hemoglobin is characterized by conversion of iron from the Fe2+ state to the Fe3+ form (1-3). Carbon monoxide (CO) is very efficient at binding to hemoglobin, having an affinity that is 250-300 times greater than that of oxygen (4-6). Formation of the hemoglobin-CO (Hb-CO) complex results in a conformation change, with a characteristic absorption spectra in the visible range (7-8). In fresh blood, as Hb-CO concentrations increase the blood takes on a cherry red appearance, a condition that is associated with CO poisoning. As noted by Simini, the term “cherry red” is somewhat subjective as there are numerous species of cherries, each with its own characteristic shade of red and coloration (9). CO levels in blood drawn from patients suffering from CO poisoning are relatively stable, and have been reported to stay constant for up to at least three years when stored in closed tubes containing anticoagulants (10-12). No information is available, however, regarding the persistence of CO in
منابع مشابه
Pnm-19: Residential Exposure to Carbon Monoxide and Spontaneous Abortion
Background: The relationship between air pollution exposure and adverse birth outcomes such as low birth weight and IUGR was studied. However, very few studies evaluated the effect of air pollution emissions on spontaneous abortion. We examined association between spontaneous abortion of the first trimester of pregnancy and ambient concentrations of carbon monoxide in Tehran. Materials and Meth...
متن کاملProtective Effects of α-Tocopherol on ABR Threshold Shift in Rabbits Exposed to Noise and Carbon Monoxide
Noise induced hearing loss (NIHL) is one of the most important occupational disease worldwide. NIHL has been found potentiate by simultaneous carbon monoxide (CO) exposure. Free radicals have been implicated in cochlear damage resulted from the exposure to noise and due to the CO hypoxia. This study examined whether α-tocopherol administration, as a free radical scavenger, causes the attenuatio...
متن کاملPhotogrammetric Responses From The Shroud of Turin
The unique results produced by simple studies of the Shroud of Turin sets this particular artifact apart from all other known artifacts. When photographed, the Shroud image appears more clearly to the human eye in the photographic negative than in the photopositive. When image-processed by a VP-8 Image Analyzer, the Shroud image produces a three-dimensional response unlike any other image so pr...
متن کاملEffects of Erythropoietin on Electrocardiogram Changes in Carbon Monoxide Poisoning: an Experimental Study in Rats
The aim of this study was to define the electrocardiogram (ECG) changes following the moderate to severe CO intoxication in rats, and also evaluating the effect of erythropoietin (EPO) on observed cardiac disturbances. The growing literature on erythropoietin effect on cardiac ischemia led us to question its effect on cardiotoxicity due to the carbon monoxide poisoning. Wistar rats were exposed...
متن کاملProtective Effects of α-Tocopherol on ABR Threshold Shift in Rabbits Exposed to Noise and Carbon Monoxide
Noise induced hearing loss (NIHL) is one of the most important occupational disease worldwide. NIHL has been found potentiate by simultaneous carbon monoxide (CO) exposure. Free radicals have been implicated in cochlear damage resulted from the exposure to noise and due to the CO hypoxia. This study examined whether α-tocopherol administration, as a free radical scavenger, causes the attenuatio...
متن کامل