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B T Adornato

Publications and source records attributed to B T Adornato.

At least 37 records · Page 2Linked to original sources
PubMed1983

The relationship of insulin receptors to hypokalemic periodic paralysis.

Single muscle fibers from a typical case of hypokalemic periodic paralysis (HOPP) have been found to be depolarized in all test media and to be cathodally blocked after exposure to insulin. The diseased fibers also bind more insulin and consume more oxygen than controls. The hypothesis proposed is that increased amount or affinity of insulin binding on the HOPP muscles causes continual depolarization in the presence of normally subthreshold concentrations of circulating insulin. presence of normally subthreshold concentrations of circulating insulin. This is because of steady effects of the hormone on passive K+ and Na+ fluxes. Additional insulin causes rapid further depolarization with paralysis. Hypokalemia follows if the insulin increment is enough to stimulate active K+ and Na+ transport.

Adolescent↗
PubMed1983

Hemopexin metabolism in patients with altered serum levels.

The rates of synthesis and degradation of hemopexin (Hx) were studied in vivo to determine the cause of altered serum levels of this protein as seen in hemolytic anemias, chronic neuromuscular diseases, and acute intermittent porphyria. The synthetic and fractional catabolic rates of Hx were measured in patients exhibiting low, normal, or elevated serum Hx levels. It was found that the elevated levels were mainly due to increased synthesis rather than decreased catabolism of Hx. In patients with elevated serum Hx levels, the mean synthetic rate of Hx (13 +/- 1.0 mg/kg/day) was twice that of the patients with normal Hx levels (6.6 +/- 0.3), whereas the fractional catabolic rate was 35.3 +/- 7.1% of the i.v. pool per day vs. 26.5 +/- 0.8 for controls. The low serum Hx levels observed in patients with sickle cell anemia appeared to be due to increased Hx catabolism (36.0 and 40.0% of the i.v. pool per day vs. 26.5 +/- 0.8 for controls) with no compensatory increase in synthesis. This latter finding is in agreement with a study in rhesus monkeys in which repeated administration of a large dose of heme caused an increase in the catabolism of hemopexin without a concurrent increase in its synthesis (J LAB CLIN MED 100:451, 1982). Our results indicate that although both synthesis and catabolism are increased in patients with elevated Hx levels, only catabolism is increased in patients with sickle cell anemia.

Adolescent↗
PubMed1982

Effect of heme administration on hemopexin metabolism in the rhesus monkey.

Clinical conditions such as hemolytic anemias and certain neuromuscular diseases in which serum hemopexin levels are either increased or decreased were simulated in rhesus monkeys by administering heme intravenously daily at three dose levels over a period of 10 days. At the lower dose of heme (0.02 to 0.04 mg/kg/day), serum hemopexin levels were elevated to 150% of control (control = 53.3 +/- 2.8 U/100 ml). At the higher dose of heme (5.0 mg/kg/day), hemopexin levels decreased to 60% of control. After an intermediate dose of heme (0.6 mg/kg/day), no change was seen in the circulating hemopexin levels. These changes appeared to be specific for hemopexin, since neither the serum haptoglobin levels nor the transferrin level was affected by the heme administration at any of the dose levels. Parameters of hemopexin metabolism revealed that after administration of the low dose of heme there was a 76% increase in the net rate of hemopexin synthesis, resulting in a 65% increase in the intravascular pool size of hemopexin. At the intermediate dose there was a 43% increase in the rate of hemopexin synthesis accompanied by a 33% increase in catabolism, resulting in no net change in serum hemopexin concentrations. At the high dose of heme there was a 57% increase in catabolism of hemopexin without a concurrent increase in synthesis, resulting in lowered circulating hemopexin levels. These findings seem to indicate a relationship between the amount of heme presented to the liver and net hemopexin synthesis.

Animals↗
PubMed1982

Quantification of acute phase reactants after muscle biopsy.

Blood concentrations of six acute phase reactants (ESR, neutrophil count, fibrinogen, haptoglobin, alpha 1-antitrypsin, and ferritin), parameters of muscle necrosis (myoglobin, CK, ALT, and AST) as well as hemopexin, iron, and TIBC were determined before and for 7 consecutive days after muscle biopsy in patients and in a control group. A muscle biopsy was chosen as a standardized surgical procedure that induces a mild transient inflammatory response. After muscle biopsy, a significant increase occurred in five (ESR, neutrophil count, fibrinogen, haptoglobin, and alpha 1-antitrypsin) of the six acute phase reactants. The concentration of serum ferritin did not show a significant change. A significant decrease was noted in the serum iron concentration and a significant increase occurred with CK and myoglobin secondary to the muscle biopsy. Thus the inflammation of a muscle biopsy produces a significant acute phase reaction.

Adult↗
PubMed1980

Cerebellar involvement in multifocal eosinophilic granuloma: demonstration by computerized tomographic scanning.

Central nervous system involvement outside the hypothalamus or pituitary in multifocal eosinophilic granuloma (MEG) is unusual. Eleven patients with MEG have been examined with cranial computerized axial tomograms (CT). Four patients with moderate to severe cerebellar dysfunction, 3 of whom had no detectable lesions by other neuroradiological techniques, were found to have cerebellar abnormalities. All of the remaining 7 patients with normal neurological examinations had normal CT scans. Computerized axial tomography is a useful technique in the evaluation of patients with MEG and neurological impairment.

Adolescent↗
PubMed1978

Myoglobinaemia in Duchenne muscular dystrophy patients and carriers: A new adjunct to carrier detection.

Myoglobinaemia was detected in 14 of 18 patients with Duchenne muscular dystrophy (D.M.D.) with a sensitive specific complement-fixation assay. Myoglobinaemia was also detected in 10 of 16 known D.M.D. carriers, including 4 with normal serum-creatine-phosphokinase activity. 9 of 27 possible carriers also had myoglobinaemia. It is suggested that this assay is a useful adjunct to present methods of carrier detection in D.M.D.

Adolescent↗
PubMed1978

Abnormal CT scans of the brain in asymptomatic children with acute lymphocytic leukemia after prophylactic treatment of the central nervous system with radiation and intrathecal chemotherapy.

Thirty-two asymptomatic patients with acute lymphocytic leukemia, who had received prophylactic cranial radiation (2400 rads) and either intrathecal methotrexate or cytosine arabinoside were studied by computed tomography of the brain 19 to 67 months after initiation of prophylaxis. Seventeen of 32 (53 per cent) had one or more abnormal findings. Dilatation of the ventricles (eight patients) and widening of the subarachnoid spaces (nine patients) were equally distributed among patients in both intrathecal-chemotherapy groups. Areas of decreased attenuation coefficient (hypodense, abnormally radiolucent regions) (four patients) and intracerebral calcification (one patient)--lesions previously described in methotrexate leukoencephalopathy--were found only in those who had received intrathecal methotrexate. Mild central-nervous-system dysfunction was detected in seven patients but did not correlate with the presence of tomographic abnormalities. Nevertheless, these tomographic findings may represent preclinical lesions. The unexpectedly high prevalence of such abnormalities contrasts with the essentially normal tomographic findings in a control group with acute lymphocytic leukemia who received no central-nervous-system prophylaxis. These results suggest that alternative approaches to such prophylaxis be considered.

Adolescent↗
PubMed1978

Depletion of serum hemopexin in fulminant rhabdomyolysis. Evidence for an interaction of hemopexin with myoglobin-derived heme.

Hemopexin is a normal serum glycoprotein that functions as a carrier for intravascularly liberated free heme. Although its role is well established in the reutilization of hemoglobin-derived heme, there have been no previous clinical data to support its suspected interaction with heme released in the degradation of myoglobin. In a patient with fulminant rhabdomyolysis, we found depletion of serum hemopexin in the presence of high serum levels of myoglobin with normal levels of haptoglobin and hemoglobin. This combination of laboratory findings is evidence for an interaction between myoglobin-derived heme and hemopexin and implies a role for hemopexin in the catabolism of myoglobin. These findings support the proposed induction mechanism for observed increases of serum hemopexin in Duchenne muscular dystrophy and in polymyositis.

Acute Disease↗
PubMed1978

Elevations of hemopexin levels in neuromuscular disease.

Hemopexin, a serum glycoprotein that binds free heme and transports it to hepatic parenchymal cells, has been measured by radial immunodiffusion. We have confirmed elevation of serum hemopexin concentration in Duchenne's muscular dystrophy patients and carries, and demonstrated elevations in dermatomyositis/polymyositis and myasthenia gravis, but not in amyotrophic lateral sclerosis. In monkeys, elevations of hemopexin levels were specifically induced by hematin injections, muscle-crush, or myoglobin injections. Myoglobin leakage is the likely explanation of hemopexin level elevation in Duchenne's dystrophy patients and carriers and in dermatomyositis/polymyositis. In myasthenia gravis there might be a slight myoglobin leakage not heretofore suspected; or, the elevation of hemopexin levels might be a new reflection of a dysimmune state in myasthenia gravis, and perhaps as such is a further incrementing factor in dermatomyositis/polymyositis. Hemopexin, presumably as a longer-phase reactant, is sometimes an index of neuromuscular disease when other data are negative or equivocal.

Animals↗
PubMed1978

Reincarnation in cultured muscle of mitochondrial abnormalities. Two patients with epilepsy and lactic acidosis.

Two unrelated 9-year-old boys failed to thrive from ages 5 and 4 years, and had focal cerebral seizures followed by transcent hemipareses. Histochemistry of their muscle biopsies showed "ragged-red" fibers, which ultrastructurally contained clusters of mitochondria having loss of crisp delineation of crista membranes and contained amorphous inclusion material and parallel-packed cristae and sometimes paracrystalline inclusions. In the patients' cultured muscles, similar mitochondrial abnormalities were present. 2,4-Dinitrophenol, introduced to the medium of cultures of normal human muscle, produced mitochondrial abnormalities similar to those of the patients', and the medium of the patients' muscle cultures worsened the mitochondrial abnormalities. This study, in demonstrating a mitochondrial defect reproducible in the cultured muscle fibers and, therefore, intrinsic to the ragged-red muscle fibers themselves, raises the possibility of a collateral mitochondrial defect in CNS cells as part of a multicellular mitochondriopathy.

Acidosis↗
PubMed1977

Radicular compression in multifocal eosinophilic granuloma. Successful treatment with radiotherapy.

A 7-year-old boy with previously diagnosed multifocal eosinophilic granuloma displayed signs and symptoms of a cervical radiculopathy. After myelograpic demonstration of extradural compression, corticosteroid and radiation therapy produced rapid and complete resolution of his symptoms. We suggest that more discrete classification of the "xanthomatoses" of the neurologic literature may provide the basis for choosing nonsurgical intervention in selected cases.

Child↗
PubMed1977

Erythrocyte survival in Duchenne muscular dystrophy.

Hemolysis was investigated in seven patients with Duchenne dystrophy. No increase in red-cell turnover was detected by indirect measurement (hemoglobin, reticulocyte count, plasma hemoglobin, serum haptoglobin) or by turnover of 51Cr-labeled erythrocytes. Our findings fail to support the likelihood of a significant erythrocyte membrane defect.

Adolescent↗