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D McKee

Publications and source records attributed to D McKee.

29 records · Page 2Linked to original sources

Unmeasured anion during severe sepsis with metabolic acidosis.

It is assumed that the development of metabolic acidosis during sepsis is secondary to lactic acidosis. We assessed the composition of the anion gap during severe sepsis induced by cecal perforation in rats. In the first experiment, cardiac output, arterial blood gases, and arterial lactate were measured over a 6 hr interval in five septic rats and in five rats serving as sham-operated controls. The cardiac output decreased from 331 +/- 32 to 172 +/- 9 ml/kg/min (P less than 0.01) in the septic rats. Although the arterial lactate was increased to 2.1 +/- 0.2 mEq/L in septic rats compared to 0.8 +/- 0.1 mEq/L in sham rats (P less than 0.01), the HCO3- was decreased to 16.5 +/- 0.6 mEq/L in septic rats versus 23.8 +/- 1.10 mEq/L in sham rats (P less than 0.01). We further investigated this bicarbonate deficit in a second study in which arterial blood was sampled at 6 hr for blood gases, and plasma Na+, K+, Cl-, HCO3-, lactate, pyruvate, beta-hydroxybutyrate, acetoacetate, citrate, creatinine, albumin, and amino acids in five septic and five sham rats. The serum anion gap was calculated as [(Na(+) + K+) - (Cl(-) + HCO3-)]. The anion gap was 21.6 +/- 1.6 mEq/L in the septic animals as compared to 13.2 +/- 0.5 mEq/L in the sham animals (P less than 0.01). There were no differences in the concentration of pyruvate, beta-hydroxybutyrate, acetoacetate, citrate, creatinine, albumin, or amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid-Base Equilibrium↗

Effect of Duchenne muscular dystrophy on enzymes of energy metabolism in individual muscle fibers.

Individual muscle fibers from patients with Duchenne muscular dystrophy at an early stage in their disease, and from apparently normal boys of similar age, were analyzed for 13 enzymes of energy metabolism. This approach avoided the serious problems with muscle homogenate assays from increases in nonparenchymal components and permitted assessment of disease changes in different fiber types. Some enzymes of glycogenolysis (phosphorylase, phosphoglucomutase, and pyruvate kinase) were decreased in dystrophic fibers of all types. Phosphofructokinase was decreased in presumptive type II fibers. Lactate dehydrogenase was increased in type I fibers and essentially unchanged in type II. Phosphoglucoisomerase was near normal. Two enzymes of glucose metabolism not involved in glycogenolysis, hexokinase and glycogen synthase, were near normal, but a third, fructose bisphosphatase, was sharply reduced. Two enzymes of oxidative metabolism, citrate synthase, and beta-hydroxyacyl CoA dehydrogenase, were unchanged or increased. Two enzymes of high energy phosphate transfer, creatine kinase and adenylokinase, were only marginally affected. The net result is to leave the type II fibers, which normally exert the greatest force, with a severe deficit in the glycogenolytic enzyme machinery to maintain that force.

Adenylate Kinase↗

Enzyme levels in individual rat muscle fibers.

Individual muscle fibers from the rat anterior tibialis and soleus muscles were each analyzed in duplicate for lactate dehydrogenase (LDH, EC 1.1.1.27), malate dehydrogenase (MDH, EC 1.1.1.37), 3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35), fumarate hydrotase (EC 4.2.1.2), glycogen phosphorylase (EC 2.4.1.1), 6-phosphofructokinase (EC 2.7.1.11), pyruvate kinase (EC 2.7.1.40), fructose-bisphosphatase (EC 3.1.3.11), and creatine kinase (EC 2.7.3.2). A few fibers were also analyzed for adenylate kinase (EC 2.7.4.3). In general, there was a wide and almost continuous spectrum of coordinated enzyme activities. In the tibialis muscle, two fiber groups could be clearly distinguished on the basis of MDH activity. The high MDH group had on the average lower LDH activity, but there was a great deal of overlap in LDH between the two groups. Less overlap was observed for phosphorylase and fructose-bisphosphatase, both inversely related to MDH. Only one main group of fibers (presumably slow twitch) was found in the soleus muscle, although enzyme activities also covered a wide range. These soleus fibers were clearly distinguished from the high MDH tibialis group by much lower activities of LDH, pyruvate kinase, and fructose-bisphosphatase.

3-Hydroxyacyl CoA Dehydrogenases↗

Gallium scanning in Paget's disease of bone: effect of calcitonin.

Calcitonin has been used in the treatment of Paget's disease of bone, and serum alkaline phosphatase level and 24 hr urinary hydroxyproline excretion have been used to follow therapeutic response. The radionuclide bone scan has been used as a visual indicator; however, there is some uncertainty as to its value in following changes in disease activity. Four patients with both serial technetium phosphate bone scans and serial gallium studies were studied. In each case the beneficial effect of calcitonin was demonstrated more accurately with gallium than with technetium diphosphonate. Since biochemical changes in Paget's disease are believed to be mediated at the cellular level and gallium uptake depends on cellular activity, it is proposed that gallium uptake is a more appropriate measure of the activity of Paget's disease than a noncellular marker such as a technetium-containing bone scan agent.

Calcitonin↗

Evaluation of 99mTc diphosphonate kinetics and bone scans in patients with Paget's disease before and after calcitonin treatment.

Eleven patients with Paget's disease of bone underwent serial total body bone scars before and after therapy with calcitonin. All patients studied showed improvement clinically as well as biochemically. Scan improvement was noted in patients with mild disease. Patients with severe disease showed either to change or only slight improvement on the serial bone scars The scan was of greatest value in determining the extent of disease, especially in 3 patients in whom biochemical values were normal. A single pulse injection of 50 M.R.C. units of salmon calcitonin produced a significant increase in the blood clearance of 99mTc diphosphonate. The mechanism of this effect is not clear from this study.

Bone and Bones↗

Improving the follow-up of patients with abnormal Papanicolaou smear results.

A review of the literature on adherence with recommended follow-up after an abnormal screening Papanicolaou smear result reveals that many women do not receive adequate follow-up. Primary care providers can influence the number of women who undergo timely colposcopy or a subsequent Papanicolaou smear by addressing common barriers to follow-up. Physicians should anticipate fears commonly experienced by women when they learn of abnormal Papanicolaou smear results, including fear of cancer, fear of pain during colposcopy, and fear of loss of sexual or reproductive function. An awareness that certain populations are at especially high risk of inadequate follow-up, including black and Hispanic women, women with less than a high school education, and women of low socioeconomic status, can help physicians target their efforts. Practical strategies for improving follow-up include speaking directly with the patient about results, emphasizing the precancerous nature of most lesions, actively preparing the patient for colposcopy by describing the procedure and its complications, and addressing fears about the common treatment options for cervical intraepithelial neoplasia. Office-based reminder systems and educational materials may also be used as adjuncts to personal contact.

Family Practice↗