Elevation rate of glycosylated hemoglobins in dogs after induction of experimental diabetes mellitus

The glycosylated hemoglobin, hemoglobin A1c, (HbA1c), which reflects average plasma glucose of the previous few weeks, has recently been used to monitor humans with diabetes mellitus. Further understanding of the HbA1c elevation rate would improve interpretation of HbA1c. We determined glycosylated hemoglobin elevation rates in 5 dogs with induced diabetes. Hemoglobin A1C was determined by an established column chromatographic technique; plasma glucose by glucose oxidase. Values were determined on 13 normal dogs and compared with values obtained weekly from surgically or chemically induced diabetic dogs. Hemoglobin A1c increased in a fashion that could be predicted by modelling. The model predicts that large changes in Hb A1c will occur within the first few weeks of a sudden change in glucose and that a new plateau will be reached at a time equal to the erythrocyte life span. In the present experiment abnormally elevated HbA1c occurred after 2 wk of hyperglycemia. The results should approximate the elevation rate after acute onset and sustained severe hyperglycemia in humans, because humans and canine are hematologically similar and thus extend previously reported studies on human out-patient diabetics.

Evaluation of a colorimetric method for canine glycosylated hemoglobin

Glycosylated hemoglobins can be used to monitor glucose status and the effectiveness of insulin therapy in canine diabetes mellitus. We have compared a colorimetric method with a time-consuming chromatographic method for measuring glycosylated hemoglobins in canine blood. Although the colorimetric method is sensitive to hemoglobin concentration, its convenience and sample size make it a possible alternative to other methods.

What do they think we do? O.T. functions as perceived by administrators and allied health professionals

Prior to preparing written material about the profession, hospital administrators in Alberta were surveyed by questionnaires in an attempt to ascertain the level of knowledge about occupational therapy roles and functions. Fifty-four respondents (administrators and other health professionals) replied to all sections of the questionnaire. Their responses have been analysed and compared to those of occupational therapists within the following areas: occupational therapists as prime agents in specific service areas, the occupational therapist's role in tasks relating specifically to physical medicine, tasks relating primarily to evaluation and treatment, tasks relating to consultation and teaching and tasks relating to administrative aspects of program management. There appears to be a lack of knowledge about the entire occupational therapy process; treatment techniques and media can be identified but how the client is assessed, goals set and the evaluation of the client's progress is not understood. Findings indicate that it is not advisable to publish and distribute information without first surveying the level of existing knowledge of the intended reader.

Glycosylated hemoglobin and canine diabetes mellitus

Minor hemoglobin fractions, HbA1a + b and HbA1c, were chromatographed and measured in seven clinically normal dogs and in seven dogs with diabetes mellitus. Concentrations of glycosylated hemoglobin, HbA1c, were significantly higher (P < 0.001) in diabetic dogs. It was concluded that this determination may be useful for monitoring glucose status and the effectiveness of insulin therapy.

The molecular pathology of chronic nitrate intoxication in domestic animals: a hypothesis

The controversial situation of chronic low level nitrate intoxication may involve oxidation of important iron-containing enzymes, much like oxidation of hemoglobin (Fe++) iron to methomoglobin (Fe+++). This oxication causes enzyme inhibition and unlike hemoglobin, which has the methemoglobin reduction system, these enzymes remain in the oxidized state, resulting in the clinical signs and conditions described. This condition may be diagnosed more accurately by measuring erythrocyte catalase activity in addition to blood or dietary levels of nitrate.

Human neonatal and maternal monocyte-macrophage and lymphocyte-mediated antibody-dependent cytotoxicity to cells infected with herpes simplex

We recently have described destruction of cells infected with herpes simplex virus by the combination of specific antibody and either lymphocytes or monocyte-macrophages. Because of the role of these cells in viral immunity and the severity of HSV in neonates and pregnant women, cord blood from 11 healthy neonates and peripheral blood from seven of their postpartum mothers were analyzed for MP and lymphocyte antibody-dependent cellular cytotoxicity against cells infected with HSV. Cord blood yielded more lymphocytes and maternal blood fewer lymphocytes than did blood from adult female control subjects. Baseline cytotoxicity of cord MP and lymphocytes and maternal lymphocytes was significantly lower than control values. There was no significant difference in MP or lymphocyte ADCC, although maternal ADCC tended to be lower than that of control subjects. Analysis of cord plasma indicated that antibody able to participate in lymphocyte and MP ADCC crosses the placenta. These data demonstrate intact ADCC but possible defects in baseline cytotoxicity with leukocytes obtained from neonates and pregnant women. Further consideration of the use of HSV antibody for prevention and therapy of neonatal HSV infection is suggested.

Reduction of fensulfothion to fensulfothion sulfide by Klebsiella pneumoniae

A cell suspension of Klebsiella pneumoniae converted the organophosphorus pesticide fensulfothion to a product that was shown by chemical oxidation, gas-liquid chromatography, infrared spectrophotometry, and mass spectrometry to be fensulfothion sulfide. Further alteration of this metabolite was not noted.

Antibody-dependent cellular cytotoxicity to target cells infected with herpes simplex viruses: functional adequacy in the neonate

The functional adequacy of antibody-dependent cellular cytotoxicity (ADCC) in the human neonate was evaluated in a 51Cr release assay which employs tissue culture cells acutely infected with type 1 or type 2 herpes simplex virus (HSV) as targets. Two aspects of ADCC were assessed: cytotoxic effector activity in cord blood mononuclear cells (MC) and the ability of the antibody mediating ADCC to pass the placenta. Although effector cell activity was readily detected in all 13 cord blood specimens tested, cord blood MC showed moderately reduced cytotoxic activity when compared with blood MC from normal adults at the same effector cell:target cell ratio. This finding suggests that effector cells in cord blood make up a reduced proportion of the total circulating MC population and may be of relevance to the newborn's increased susceptibility to HSV infection. On the other hand, the number of MC in cord blood was found to be almost twice that of adult blood, suggesting that the absolute number of ADCC effector cells in cord blood was within the adult range. The antibody mediating ADCC to HSV-infected cells was shown to be transferred quantitatively across the placenta, providing further evidence that it is an IgG immunoglobulin.

Antibody-dependent cell-mediated cytotoxicity to target cells infected with type 1 and type 2 herpes simplex virus

The phenomenon of antibody-dependent cell-mediated cytoxicity (ADCC) has been extended to include target cells acutely infected with herpes simplex type 1 virus (HSV-1) or herpes simplex type 2 virus (HSV-2) in an in vitro system that employs immune human serum and human blood mononuclear cells. The cytotoxic reaction was detectable after 1 hr of incubation and was complete between 4 and 8 hr. The amount of ADCC noted was directly proportional to the logarithm(10) of the effector: target cell ratio (E:T), and ADCC was noted at E:T as low as 1:1. The mononuclear effector cell was present in the blood of both HSV immune and non-immune individuals. The immune serum factor was demonstrated to be an antibody with specificity for HSV membrane antigen(s) and was reactive with target cells infected with either of the two HSV types. The antibody rendered the mononuclear cell cytotoxic by sensitization of the target cell rather than by direct attachment to or "arming" of the mononuclear cell. The physiochemical properties of the antibody as well as its presence in cord blood demonstrated that it is an immunoglobulin on the IgG class.