Oxygen-carrying Capacity Of Hemoglobin Research Articles

Liver as an alternative specimen for carbon monoxide detection when blood is unavailable

Carbon monoxide (CO) is one of the most toxic gases, responsible for a large number of deaths in the cases of smoke and fire burning. CO has the ability to combine reversibly with hemoglobin to form carboxyhemoglobin (HbCO), which denotes its chemical asphyxiant character. This leads to decreased oxygen carrying capacity of hemoglobin. Consequently, the determination of CO concentration and the degree of HbCO saturation in blood are frequently tested in toxicology laboratories. Recently, only the blood is considered the sample of choice for the detection of CO. Different methods for CO detection and estimation in blood have been employed including colorimetric screening, spectrophotometry and gas chromatography (GC). But when blood is not available in fire exposure postmortem cases, it is not possible to conclude the cause of death. Objective of this study is to highlight the significance of liver as specimen of interest in fatal carbon monoxide poisoning in relevance to detection in postmortem specimen of blood. In this study, the authors considered data from one hundred and fifty fire burn cases for carbon monoxide detection. Among these cases, liver and blood were tested simultaneously for CO confirmation. These cases included confirmation of carbon monoxide using colorimetric a technique by palladium chloride micro diffusion assay in which metallic palladium is obtained after reduction of palladium chloride present in impregnated paper strips. The results were only considered positive if the strip develops black color strip with silver glitter. Carbon monoxide/drug-free whole blood was used as the negative control while 12% CO containing whole blood was used as a positive control. One hundred and twenty-one (80.6%) cases were found positive for the presence of carbon monoxide both in blood and liver. Of these, 9.9% cases accounted for carbon monoxide detection only in blood. However, the remaining 9.5% of cases were found negative both for blood as well as liver. Liver was positive for carbon monoxide in approximately 90.5% of the cases under test when the blood was also positive for these samples. As the heme is found both in blood and liver, so there is strong evidence of CO detection in liver. This will be a huge method for forensic investigations when the blood is unavailable but liver is available. This method will also be valuable for an exhumed putrefied postmortem sample when only liver is available.

Impact of calcium nitrate supplementation on the oxygen-carrying capacity of lactating sows and their offspring.

Calcium nitrate supplementation has recently been suggested to provide potential benefits to sows and, in particular, their offspring when administered at a level of 1,200 ppm in feed shortly before farrowing through lactation. More specifically, nitrate supplementation has been suggested as one opportunity for improved placental and/or fetal blood flow and has been hypothesized in previous work to be important to the swine industry in light of the global trend toward larger litter sizes. The benefit is likely manifested through exposure to the nitrate moiety, but interestingly, nitrate has historically been considered a compound of concern for swine. High levels of nitrate once metabolized to nitrite can interfere with the oxygen-carrying capacity of hemoglobin, resulting in increased methemoglobin and, subsequently, methemoglobinemia (MetHb) if the animal is deprived of significant amounts of oxygen; however, the level of nitrate exposure necessary to induce MetHb in sows is not clearly defined. This work was undertaken to examine methemoglobin levels in sows and piglets exposed to the potentially beneficial levels of 1,200 and 6,000 ppm nitrate added to their diets over the course of the periparturient period. Other oxygen capacity blood variables were evaluated (e.g., hemoglobin, hematocrit, and various measures of hemoglobin and red blood cell volumes and concentrations), as well as performance endpoints (weight changes and feed intake) and general observations over the 27-d period. No evidence of treatment-related toxicity manifestation was observed at these supplemental levels. Nearly all oxygen-related variables were affected by time (independent of treatment), indicating adaptive general effects of farrowing. These findings support the hypothesis that MetHb is not a concern up to at least 6,000 ppm supplemental nitrate exposure, even in combination with additional nitrate in the sow’s daily diet. This work is important to help swine producers understand that consideration of nitrate benefit should outweigh concern for risk of nitrate-induced toxicity.

Impact of iron deficiency anemia on cognition of school children of South India

Background: Iron Deficiency Anemia (IDA) is the most widespread anemia among all population segments in India. IDA curtails the oxygen carrying capacity of hemoglobin and thus prevents complete vitality and development of the brain during childhood. Timely intervention and correction of anemia is therefore very important. Objectives: 1. To determine the hemoglobin levels of 30 school children. 2. To perform cognition tests including Raven’s score and visual memory test. Materials and Methods: Study included 30 school going children between the ages of 9-13 years. Informed consent was obtained from the guardians. Subjects were screened for anemia by determining Hb (g%) and blood indices. Cognitive function was assessed by Raven’s scoring and visual memory test. Cognitive status was then compared between anemic and non-anemic children. Results: Mean age of participants was 10.73 years. 26.66% of the subjects were anemic (mean hemoglobin of 10.42 g%). 73.34% of the participants were non anemic (mean hemoglobin of 12.16 g%). Raven’s score was significantly low in anemic children (p

Association between Red Blood Cell Transfusion and Bronchopulmonary Dysplasia in Preterm Infants

Anemia and the need for transfusion of packed red blood cells (PRBCs) are common in preterm infants. PRBC transfusion increases the oxygen carrying capacity of hemoglobin and may result in higher rates of organ dysfunction. To determine whether PRBC transfusion in preterm infants is associated with an increased incidence of bronchopulmonary dysplasia (BPD), this retrospective study was performed on neonates with birth weights ≤ 1,500 g or gestational age ≤ 32 weeks admitted from August, 2008 to November, 2013. Infants who received PRBC transfusion before the diagnosis of BPD and those who did not receive PRBC transfusion or received PRBC transfusion after diagnosis of BPD were compared for incidence of BPD and other morbidities. Of 231 preterm infants, 137 received PRBC transfusion before BPD was diagnosed (group 1) and 94 did not (group 2). The incidence of BPD was significantly higher in group 1 than in group 2 (37.2% vs. 2.1%, P < 0.00001). After adjusting for potential risk factors, the adjusted odds ratio for BPD was 9.80 (95% confidence interval, 1.70–56.36; P = 0.01). This study demonstrated an association between PRBC transfusion and BPD in preterm infants. A cautious approach to PRBC transfusion in these infants is warranted.

Root Effect Hemoglobin May Have Evolved to Enhance General Tissue Oxygen Delivery

The Root effect is a pH-dependent reduction in hemoglobin-O2 carrying capacity. Specific to ray-finned fishes, the Root effect has been ascribed specialized roles in retinal oxygenation and swimbladder inflation. We report that when rainbow trout are exposed to elevated water carbon dioxide (CO2), red muscle partial pressure of oxygen (PO2) increases by 65%--evidence that Root hemoglobins enhance general tissue O2 delivery during acidotic stress. Inhibiting carbonic anhydrase (CA) in the plasma abolished this effect. We argue that CA activity in muscle capillaries short-circuits red blood cell (RBC) pH regulation. This acidifies RBCs, unloads O2 from hemoglobin, and elevates tissue PO2, which could double O2 delivery with no change in perfusion. This previously undescribed mechanism to enhance O2 delivery during stress may represent the incipient function of Root hemoglobins in fishes.

Epistasis Among Adaptive Mutations in Deer Mouse Hemoglobin

Epistatic interactions between mutant sites in the same protein can exert a strong influence on pathways of molecular evolution. We performed protein engineering experiments that revealed pervasive epistasis among segregating amino acid variants that contribute to adaptive functional variation in deer mouse hemoglobin (Hb). Amino acid mutations increased or decreased Hb-O2 affinity depending on the allelic state of other sites. Structural analysis revealed that epistasis for Hb-O2 affinity and allosteric regulatory control is attributable to indirect interactions between structurally remote sites. The prevalence of sign epistasis for fitness-related biochemical phenotypes has important implications for the evolutionary dynamics of protein polymorphism in natural populations.

Parallel Variation in Haemoglobin Concentration in Nestling-Rearing Blue TitsCyanistes caeruleusand Great TitsParus major

High metabolic rates of birds demand an efficient oxygen transport system; this is ultimately based on the oxygen carrying capacity of haemoglobin. Therefore patterns of variation in blood haemoglobin content of wild birds are an important aspect of functional ecology. In this paper we report results concerning variation in haemoglobin con- centration in the blood of adult Blue Tits Cyanistes caeruleus and Great Tits Parus major during the nestling rearing peri- od (days 7-15 of nestlings life) of first broods in central Poland in 2003-2009. The most important findings of this study are: (i) average haemoglobin concentration in blood differs between Blue Tits and Great Tits, with higher values in Blue Tits; (ii) males differ from females in both these species, with higher values in females, and (iii) there is also significant variation among years, with parallel tendencies for both species. We explain the patterns of haemoglobin content vari- ation in adult tits by differences in metabolic demands for oxygen transported by blood. The demands are higher for the smaller-bodied species (Blue Tits), heavier working sex (females) and in years with worse physical and trophic con- ditions, though only non-significant relationships with weather conditions (temperature and rainfall) or food availabil- ity (measured by frassfall) were found during our long-term study.

Drug‐induced methaemoglobinaemia following elective coronary artery bypass grafting

Dapsone can alter the oxygen carrying capacity of haemoglobin. Some patients are more susceptible to these effects because of genetic factors, comorbidities or peri-operative factors such as anaemia. We present a 57-year-old lady who underwent elective coronary artery bypass grafting. Deterioration in neurological and respiratory condition prompted a review of her drug treatment. A combination of long-term dapsone therapy, co-existing cardiac and respiratory disease, postoperative anaemia and renal impairment contributed to her decompensation, despite a relatively low level of methaemoglobin. Successful management included stopping dapsone therapy, supportive care and administration of ascorbic acid.

Simple Identification of A Cross-Linked Hemoglobin by Tandem Mass Spectrometry in Human Serum

Hemoglobin-based oxygen therapeutics are prepared by reaction of hemoglobin with cross-linking molecules and are utilized as blood substitutes. They can be used as doping agents to increase the oxygen-carrying capacity of hemoglobin. We have compared a glutaraldehyde-polymerized bovine hemoglobin (Oxyglobin, Biopure Corp.) with natural bovine hemoglobin by mass spectrometry in order to detect specific fragment ions of the cross-linked protein for further potential applications in doping control of human blood samples. HCl acid (6 N) hydrolysis was performed in parallel on both proteins. Hydrolysates were then analyzed by direct infusion electrospray mass spectrometry (ESIMS) using a triple quadrupole mass spectrometer. Confirmation and precision were obtained by LC-ESIMS(n) experiments performed on an ion trap mass spectrometer. Chromatographic and mass spectrometry data allowed detection of two potential Oxyglobin-specific ions--m/z 299 and 399--that were shown to lose a 159 u neutral fragment under collision-induced dissociation conditions. Thus, monitoring of constant neutral loss of 159 u on acid hydrolysates of human serum samples spiked with different amounts of Oxyglobin has proved to be an efficient screening method to specifically detect and identify Oxyglobin. LC-MS of the spiked serum sample hydrolysates enabled detection of Oxyglobin at a detection limit of 4 g x L(-1).

The effects of acid-base disturbances on cardiovascular and pulmonary function

Disturbances in acid-base balance are commonly met problems in clinical medicine and decisions about their treatment are of great importance in patients with cardiopulmonary problems, in whom acid-base disturbances may be especially critical.Similarly, cardiopulmonary function may be significantly compromised even in patients with no intrinsic heart or lung disease, in the face of acid-base disturbances.It is essential, therefore, to understand the physiological consequences of these disturbances on the cardiovascular and pulmonary system. Of major importance is the effect of acid-base disturbances on the delivery of to the various tissue cells of the body.In order to understand all the pathophysiological mechanisms involved it is necessary to review the effects of acid-base changes on the heart, the peripheral vessels, the lungs, and the diffusion of between air, blood, and tissues. The requirement for by the various tissue cells of the body is met by the combined cardiovascular and pulmonary systems, which function as a unit termed the oxygen transport system of the body.The movement of from the ambient air to the tissue cells involves ventilation, pulmonary perfusion, diffusion, oxygen-carrying capacity of hemoglobin, cardiac output (including cardiac muscle performance), systemic distribution of flow, and finally the delivery capacity of hemoglobin.It is important to understand the effects of changes in pH on each of these steps in the chain.

Air pollution in nurseries: Correlation with a decrease in oxygen-carrying capacity of hemoglobin

A decrease in the hemoglobin-oxygen-carrying capacity of healthy newborn infants correlated with the level of air pollution. Pollution was estimated from daily concentrations of carbon monoxide obtained at a city pollution monitoring station; this was used as an index of the general level of air pollution. The percentage decrease in oxygen-carrying capacity was also related to the duration of postnatal exposure.