Erythrocytes regeneration

Averages of Erythrocyte Regeneration Curves at Two Different Initial Erythrocyte Levels, Following the Administration of the Primary Factor with and without a Complete Supplement of Accessory Factors The number of patients studied in each period is shown by the small figures above each curve. The quantity at the end of each curve denotes the calculated average daily amount of primary fraction administered, expressed in terms of amount of fresh liver from which the extract was derived. 

Average Erythrocyte Regeneration Curves Following the Administration of Various... 

These extracts prepared by Karrer were tested by Koller (71). These fractions which were tested at about 2 mg. a day indicated good activity altnoiigii in some cases the erythrocyte regeneration was slower than in those cases presented by other investigators. His cases are presented in Table IX. 

When animal tissues cannot be supplied with sufficient oxygen to support aerobic oxidation of the pyruvate and NADH produced in glycolysis, NAD+ is regenerated from NADH by the reduction of pyruvate to lactate. As mentioned earlier, some tissues and cell types (such as erythrocytes, which have no mitochondria and thus cannot oxidize pyruvate to C02) produce lactate from glucose even under aerobic conditions. The reduction of pyruvate is catalyzed by lactate dehydrogenase, which forms the l isomer of lactate at pH 7 ... 

The enzyme levels in the different tissues examined by Cordonnier and Bernardi 35) were found to vary by as much as three orders of magnitude. The highest acid DNase levels were found in lymphatic and tumoral tissues the lowest were found in cells (sperms and erythrocytes) that do not reproduce themselves anymore. This relationship between levels of acid DNase activity and capacity for proliferation or regeneration of a given tissue had already been observed by Allfrey and Mirsky 68). 

Interactive models, which have been developed and validated, exist for countermeasures which compete with NA inhibition of ChE or the regeneration of the free enzyme from its inhibited state, such as pyridostigmine and oximes, respectively. Numerous data in the literature describe the kinetics of interaction between nerve agents and other OPs and specific countermeasures at active enzyme sites of eoncem. For example, Davies and Green (1956) have measured the rate of reactivation of inhibited erythrocyte... 

Cobalmin Deficiency. Pernicious anemia is the disease associated with vitamin Bi2 deficiency. It is usually caused by the inability to produce intrinsic factor. Indeed, many times the vitamin must be administered by injection. The blood picture, a megaloblastic anemia, is indistinguishable from that caused by folic acid deficiency. Indeed folic acid supplements can mask the blood picture. This is illustrated in Fig. 8.53. Removal of ad-enosyl cobalamin eliminates the regeneration of tetrahydrofolate during the methylation of homocysteine to methionine. Folic acid supplements provide a fresh source of tetrahydrofolate coenzymes. DNA synthesis can continue and new erythrocytes form. Excess folic acid also may compete for the available vitamin, further exacerbating vitamin deficiency. 

Cells that lack mitochondria (e.g., erythrocytes) or contain mitochondria but under hypoxic conditions (e.g., vigorously and repeatedly contracting muscle) reduce pyruvate to lactate by lactate dehydrogenase (LDH), which uses NADH as a reductant. This reduction regenerates NAD+, which is required for continued oxidation of glyc-eraldehyde 3-phosphate. 

KOnig and Gratzel first reported the Pz detection of hiunan erythrocytes [127,128]. The later was an improved version of the sensor. Polyethyl-eneimine was used to immobilise the antibody to the crystal, which was stable for 10 weeks, if stored dry at room temperature or 4°C, without detectable loss in activity. Regeneration of the surface was improved from eight to 12 times without detectable loss in activity. This was done by the addition of a synthetic peptide, which competed for the bound antigen and allowed regeneration of the antibody surface without the use of harsh chemicals. Analysis in blood was carried out. 

The trace amounts of 2,3 BPG found in cells other than erythrocytes is required for the phospho-glycerate mutase reaction of glycolysis, in which 3-phosphoglycerate is isomerized to 2-phosphoglycerate. As the 2,3 BPG is regenerated during each reaction cycle, it is only required in catalytic amounts. 

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