Intralabyrinthine osteogenesis in Cogan's syndrome

Temporal bones from a 64-year-old man who had Cogan's syndrome were examined by light microscopy. Although tissues of the middle ear appeared unremarkable, extensive ectopic bone formation was observed bilaterally in the inner ear membranous labyrinth. Such osteogenesis completely obliterated the cochlear compartments apically. Only the scala tympani compartment of the basal cochlear turn remained patent. Ectopic bone tissue was observed also in the vestibular semicircular canals. Marked degeneration of eighth nerve fibers and associated ganglion cells also was observed. To our knowledge, this report represents only the fourth temporal bone findings of Cogan's syndrome and demonstrates a more advanced pathologic state of inner ear pathology than those reported previously.

Pharmacokinetics of procainamide hydrochloride in dogs

Pharmacokinetics of procainamide hydrochloride were studied in 2 groups of dogs. In a group of 6 dogs, procainamide was administered IV at a small dose of 8 mg/kg (group 1), and blood samples were obtained for 3.5 hours. In another group of 6 dogs, procainamide was administered IV and orally at an average dose of 25.5 mg/kg (group 2) in a crossover manner. Blood samples were obtained for 48 hours. In 2 dogs (previously used in part II), N-acetylprocainamide (NAPA) was administered IV at a dose of 10 mg/kg. Plasma samples were assayed for procainamide by fluorescence polarization immunoassay, and NAPA samples were assayed by high-performance liquid chromatography. In group 1, the elimination of procainamide was described by a 1-compartment, open pharmacokinetic model. The elimination half-life was 2.43 hours, the apparent volume of distribution was 1.44 L/kg, and the systemic clearance was 0.412 L/kg/hr. In group 2, 2 of the 6 dogs were described by a 1-compartment model, and 4 of the 6 dogs were described with a 2-compartment pharmacokinetic model. The elimination half-life for the IV dosage was 2.85 hours, the apparent volume of distribution was 2.13 L/kg, and the systemic clearance was 0.519 L/kg/hr. For the orally administered dose, the bioavailability was 85%, and the absorption half-life was 0.5 hours. There was no evidence of acetylation of procainamide to NAPA or deacetylation of NAPA to procainamide. The estimated elimination half-life of NAPA was 4.7 hours.

Endotoxin-induced bovine mastitis: immunoglobulins, phagocytosis, and effect of flunixin meglumine

Milk whey immunoglobulins (Ig) and phagocytosis of staphylococci by milk polymorphonuclear neutrophilic leukocytes (PMN) were measured in 12 cows (allotted to 6 pairs) during acute bovine mastitis induced by intramammary inoculation of endotoxin. Six of these cows (or 1 in each pair) were treated with flunixin meglumine and were compared with the others (given only saline solution). The endotoxin inoculation comprised 10 micrograms of Escherichia coli O26:B6 lipopolysaccharide injected into one of the rear quarters (mammae). Flunixin meglumine was administered parenterally at a dosage of 1.1 mg/kg every 8 hours (total of 7 doses) beginning at 2 hours after endotoxin was injected. Milk samples were obtained, and whey samples were prepared from each quarter of each cow 3 times before inoculation and at 2, 4, 8, 12, 24, 48, 72, 96, 120, 144, 168, and 336 hours after endotoxin was inoculated. Significant increases (P less than 0.05) in milk whey IgG1, IgG2, IgM, and IgA concentrations were observed in whey samples from endotoxin-inoculated quarters. Greatest relative increase was seen for IgG2. Increased whey Ig concentrations were not observed in quarters which were not inoculated with endotoxin. Concentrations of whey IgG1 and IgM in endotoxin-inoculated quarters were significantly (P less than 0.05) decreased in flunixin meglumine-treated cows, compared with those in saline solution-treated cows. Significant increases in phagocytosis of staphylococci by milk PMN were observed in whey samples from endotoxin-inoculated quarters. Significant differences in PMN phagocytosis were not found in whey samples from cows given flunixin meglumine when compared with whey samples from cows given saline solution.

Recurrent meningoencephalitis with recovery from Behçet's disease

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Endotoxin-induced bovine mastitis: arachidonic acid metabolites in milk and plasma and effect of flunixin meglumine

Arachidonic acid metabolites (AAM) were measured in milk and plasma during the course of acute endotoxin-induced mastitis in 12 lactating cows. Mastitis was induced by intramammary challenge exposure with 10 micrograms of Escherichia coli (026:B6) endotoxin. Endotoxin was injected into the teat cistern via the teat canal of a single randomly selected rear quarter of each cow. Concentrations of prostaglandin (PG) F2 alpha and thromboxane (Tx) B2 in fat-free unextracted milk and of 15-keto-13,14-dihydro-PGF2 alpha in plasma were measured by radioimmunoassay. Total production of AAM in milk was determined by measuring quarter milk production. The AAM were compared in 6 cows administered flunixin meglumine (1.1 mg/kg of body weight) and in 6 cows administered saline solution. Concentrations of TxB2 in milk were significantly (P less than 0.001) increased during the early course of acute mastitis in endotoxin-treated quarters of cows not administered flunixin meglumine. Peak concentrations of TxB2 in milk occurred at 8 hours after endotoxin inoculation. Flunixin meglumine treatment produced significant (P less than 0.05) reductions in milk TxB2 and plasma 15-keto-13,14-dihydro-PGF2 alpha concentrations. Concentrations of PGF2 alpha in milk and total PGF2 alpha and TxB2 production per quarter per milking were not significantly influenced by endotoxin challenge or by flunixin meglumine treatment.

Efficacy of flunixin meglumine for the treatment of endotoxin-induced bovine mastitis

The clinical effect of flunixin meglumine administration was determined in cows with acute mastitis induced by intramammary administration of endotoxin. In 12 lactating cows, 10 micrograms of Escherichia coli 026:B6 endotoxin were administered via a teat cannula into the teat cistern of single randomly selected rear quarters. Cows were challenge exposed as pairs. One cow in each pair was administered parenteral flunixin meglumine (6 cows) and 1 cow per pair was administered saline solution (6 cows). Multiple doses (7) of 1.1 mg of flunixin meglumine/kg of body weight or saline solution were administered at 8-hour intervals beginning 2 hours after endotoxin. Cow and quarter clinical signs as well as milk somatic cell concentrations, bovine serum albumin, electrical conductivity, and milk production were determined before and for 14 days after endotoxin inoculation. Intramammary endotoxin produced signs characteristic of acute coliform mastitis. Quarter and systemic abnormalities occurred and milk production was reduced by approximately 50% at 12 hours after endotoxin. Flunixin meglumine therapy significantly (P less than or equal to 0.05) reduced rectal temperatures and quarter signs of inflammation and improved clinically graded depression when compared with these signs in saline solution-treated controls. Milk production and laboratory indicators of inflammation in milk were not significantly (P greater than 0.05) different for flunixin meglumine vs saline solution controls. The clinical response observed was consistent with the antipyretic, analgesic, and anti-inflammatory properties of flunixin meglumine.

Alteration in the arrhythmogenic dose of epinephrine (ADE) following xylazine administration to halothane-anesthetized dogs

The arrhythmogenic dose of epinephrine (ADE) was determined in six dogs during halothane (1.35%) anesthesia before and after xylazine administration (1.1 mg/kg, i.v. bolus; 1.1 mg/kg/hr, i.v. infusion). The arrhythmogenic dose was determined by constant infusion of freshly mixed epinephrine (100 microgram/ml). The ADE was defined as the total dose of epinephrine which produced four or more intermittent or continuous premature ventricular contractions within a 15-sec period. Total dose was calculated as a function of infusion rate and time to arrhythmia. Following xylazine administration, ADE significantly decreased from 6.28 +/- 0.522 to 4.17 +/- 0.679 micrograms/kg. At the end of i.v. xylazine bolus administration, heart rate significantly decreased (115 +/- 4 to 99 +/- 4.9 b.p.m.), and mean arterial pressure significantly increased (83 +/- 4.0 to 122 +/- 3.4 mm Hg). Heart rate measured immediately prior to epinephrine-induced arrhythmia formation was significantly increased following xylazine administration (177 +/- 8 vs 78 +/- 3 b.p.m.). Mean arterial blood pressure was unchanged. Apparently, xylazine, a mixed alpha agonist, potentiated halothane-induced myocardial sensitization to ventricular arrhythmogenesis and was associated with a significant increase in heart rate, but not blood pressure, during subsequent epinephrine infusions.

Drug therapy during pregnancy and in the neonate

This article presents important clinical pharmacologic aspects of drug therapy during pregnancy. It reviews the potential adverse effects on the mother and conceptus caused by drugs and includes specific recommendations for therapy. Extensive tables are included that list drugs that are safe and those that are contraindicated during pregnancy.

Plasma cortisol and norepinephrine concentrations in castrated male pigs maintained in pairs in outdoor pens and in a confinement finishing house: assessment of stress

A catheter-backpack system was developed for repeated blood collection in pigs. Castrated male pigs (n = 12) were maintained in pairs in outdoor pens and later in a slotted-floor confinement finishing house. Blood collection required no restraint and appeared to be stress free. Serum cortisol concentration was unchanged by mode of maintenance. However, diurnal variation of cortisol was more pronounced when pigs were housed. A significant decrease (P less than 0.05) in serum norepinephrine concentration occurred during the housing period.

Pharmacokinetics of lithium in the dog

The pharmacokinetics of lithium were determined in eight adult dogs. The data were fitted to a two-compartment model. Single intravenous doses of lithium chloride, and single oral doses of lithium carbonate were used. The mean plasma lithium half-life (t1/2) following the single intravenous dose was 21.6 h, and the mean apparent specific volume of distribution of the central compartment (V'c) was 0.189 l/kg. Mean bioavailability was 78.8% following oral administration.

Atypical ocular bobbing in acute organophosphate poisoning

Atypical ocular bobbing resulted from an intentional poisoning from dimpylate (Diazinon), an organophosphate compound. In discussing the possible foci and mechanism for atypical ocular bobbing associated with acute organophosphate poisoning, we suggest acetylcholine as a neurotransmitter substance within the ocular motor pathway. A literature review has not shown any previous reported cases with this sign.

Liver autophagy in the influenza B virus model of Reye's syndrome in mice

Biochemical evidence is presented for the autophagic destruction of liver mitochondria in the influenza B virus model of Reye's syndrome in mice. Separation of lysosomes and autophagic vacuoles from mitochondria was accomplished by prior treatment of the mice with Triton WR-1339, resulting in uptake of detergent by these organelles (tritosomes), reducing their densities. The organelles were banded in a discontinuous sucrose gradient. Total protein in the heavy tritosomal fraction increased from 1-2% in controls to 7-8% in virus-treated animals. Ornithine carbamoyl transferase (OCTase), a mitochondrial marker, increased from 2-3% (controls) to 11-15% (virus-treated), and glucose-6-phosphatase, a marker for endoplasmic reticulum, increased from 1-2% (controls) to 8-10% (virus-treated). beta-Galactosidase, a soluble enzyme in the lysosome, and OCTase also increase in the cell extract fraction following virus treatment, indicating that there was turnover of heavy lysosomal contents.

Mouse influenza B virus model of Reye's syndrome. Encephalopathy and microvesicular fatty metamorphosis of the liver by influenza B virus following intravenous administration in mice

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Influenza B virus model of Reye's syndrome in mice: the effect of aspirin

Aspirin is a possible cofactor with influenza B virus in Reye's syndrome. In an attempt to determine whether single or multiple doses of acetylsalicylic acid (ASA) alter mortality in an influenza B virus mouse model of Reye's syndrome, either ASA (300 to 667 mg/kg) or saline was given intraperitoneally to 3-week-old Balb/c mice. Two hours later, one median lethal dose (LD50) of influenza B/Lee virus was given intravenously. Mortality was not significantly increased by the single ASA dose. Blood ASA levels rose as high as 68 mg/dl. The average ASA blood levels in mice 12 hours after receiving the virus plus 667 mg/kg ASA was 22.6 mg/dl, which was significantly higher than the 3.4 mg/dl for mice who received saline plus ASA. No significant increase in mortality occurred in mice given 67 mg/kg ASA twice daily for 7 days and one LD50 dose of virus on day 4. We conclude that a single dose of ASA at up to half the median lethal dose or multiple doses of ASA do not significantly increase mortality in this influenza virus model of Reye's syndrome. However, influenza B virus infection appears to interfere with ASA metabolism.

Respiratory epithelial cells masquerading as agents of primary amebic meningoencephalitis: distinguishing features

CSF does not normally contain motile cells within flagella or cilia. When motile cells are seen in the CSF, they may be incorrectly assumed to be amebae. We studied a patient with a traumatic mucocele, in whom motile ciliated respiratory epithelial cells were seen in the CSF and within a frontal lobe brain abscess.

Preparation and characterization of antibodies with specificity for the amino-terminal tetrapeptide sequence of the platelet-derived connective tissue activating peptide-III

Antisera selectively reactive with the N-terminal tetrapeptide sequence of the platelet-derived connective tissue activating peptide-III mitogen were prepared and characterized. Solid phase synthesized Z-Asn-Leu-Ala-Lys(Z)-OH tetrapeptide representing the N-terminus of the mitogen was used as an immunogen after carbodiimide mediated coupling to methylated bovine serum albumin carrier and subsequent removal of Z groups. Anti-tetrapeptide sera demonstrated cross-reactivity to the mitogen but not beta-thromboglobulin, fibroblast growth factor, or epidermal growth factor, and a limited cross-reactivity to parathyroid hormone. The studies indicate that the N-terminal sequence of the mitogen is accessible for binding with antibody and the antitetrapeptide sera provide a reagent for the selective measurement of biologically active mitogen in the presence of structurally similar beta-thrombo-globulin. In addition, computer analysis of amino acid sequences revealed that few proteins contain the Asn-Leu-Ala-Lys sequence and of those that do, many are retroviral proteins or transforming polyproteins.

Neuropathology of ornithine carbamyl transferase deficiency

Neuropathologic findings in two cases of ornithine carbamyl transferase (OCT) deficiency are presented. In one, a boy 3 days old, the only abnormality related to the enzyme defect was metabolic gliosis which was unusual in distribution being present mainly in the brain stem. In the other case, a girl who died at the age of 2 3/12 years, the brain showed metabolic gliosis in typical location, widespread ulegyria, and moderate atrophy of the internal granular layer in the cerebellum accompanied by development of expansions of Purkinje cell dendrites. Case 2 demonstrates how rapidly changes previously demonstrated in the cerebral cortex after a few months of illness can proceed to massive hemispheric destruction. By now ulegyria has been observed in several disorders of the urea cycle.

Drugs and the liver

The authors discuss the liver's influence on drug disposition in the body and the influence of drugs on the liver. Drug-induced hepatotoxicity with regard to mechanisms and causative agents is discussed, as well as administration of drugs to patients with existing liver disease.

Inner ear anomalies in Waardenburg's syndrome associated with Hirschsprung's disease

Congenital inner ear anomalies are reported in temporal bones of a 22-month-old boy with Waardenburg's syndrome and Hirschsprung's disease. Although no changes in the central auditory pathway were identified, peripheral lesions of the cochlear and vestibular membranous labyrinth were observed. Bilateral atrophy of the organ of Corti and stria, and a sparsity of spiral ganglion cells were observed in the cochlea. Degeneration of the vestibular end organs, including a loss of Scarpa's ganglion cells, was also seen. This is the first report of temporal bone histopathology associated with Waardenburg's syndrome and Hirschsprung's disease. The pathoembryology of these inner ear anomalies associated with aganglionosis of the colon supports the hypothesis that Waardenburg's syndrome and Hirschsprung's disease are hereditary defects of neural crest cells.

Efficacy of ethylenediamine dihydriodide in the prevention of naturally occurring foot rot in cattle

The efficacy of an ethylenediamine dihydriodide containing salt mixture was evaluated with regard to the prevention of naturally occurring foot rot in pastured cattle. Ninety-six cattle were assigned to the treatment group and 96 were assigned to the control group. The groups were allowed consumption of salt-mineral mixtures, ad libitum, that were identical, except with respect to iodine concentration. The control group's mixture contained 0.0025% iodine and the treatment group's mixture contained 0.125% iodine (0.156% ethylenediamine dihydriodide). The incidence of foot rot was measured, as was the severity of the lesions and accompanying lameness. The incidence of foot rot in the control group (20.8%) was significantly (P less than 0.05) greater than the incidence in the treatment group (8.3%). The severity of foot rot was greater (P = 0.024) in the control calves vs the treatment calves. Total serum iodine concentrations were measured in the 2 groups on days 0, 46, and 130 of the experiment. The serum iodine values of the treatment group on day 46 (46 +/- 19.8 g/dl) and day 130 (23 +/- 12.3 g/dl) were significantly different (P less than 0.01) than the serum iodine concentrations of the control animals and the pretreatment values (day 0) of both groups. Production was measured via calf weaning weights. There were no detectable differences between the 205-day adjusted weaning weights of the calves in the control group vs the calves in the treatment group. Clinical signs of iodism were not observed in the cattle involved in this study.

Antisera specificities to 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide adducts of proteins

Animals were immunized with either 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDCI)-coupled peptide hapten-protein carrier conjugates or with N-acylurea EDCI derived protein carrier. Sera from all animals demonstrated antibody to N-acylurea EDCI when tested by double immunodiffusion using N-acylurea EDCI coupled to a heterologous carrier. Two rabbit antisera, one produced to EDCI-coupled peptide-24-thyroglobulin and another produced to N-acylurea EDCI derived thyroglobulin were further characterized using an enzyme-linked immunosorbent assay (ELISA). Competitive binding assays using either EDCI-coupled peptide-protein conjugates or N-acylurea EDCI derived proteins demonstrated the presence of N-acylurea EDCI reactive antibodies. Such antibodies were also shown to react with the EDCI isourea employed as inhibitor. The specificity of the anti-EDCI antibodies to portions of the EDCI molecule was demonstrated using structural analogues of EDCI. Both 3-dimethylaminopropylamine and 2-dimethylaminoethanol effectively inhibited anti-N-acylurea EDCI reactivity. These results show that when EDCI is used as a coupling agent, antibody is produced to N-acylurea EDCI-carrier, the antibody being primarily directed to the 3-dimethylaminopropyl end of the EDCI molecule.

Cisplatin neuropathy. Clinical, electrophysiologic, morphologic, and toxicologic studies

Ten of 11 patients with ovarian cancer receiving cisplatin developed a distal sensory neuropathy, manifested early by decreased vibratory sensibility in toes and depressed ankle jerks and later by uncomfortable paresthesias. Eleven patients receiving cisplatin, 50 mg/m2 monthly (mean total, 580 mg/m2) were studied prospectively with monthly neurologic examinations and conduction velocity determinations of median, peroneal, and sural nerves. Early signs were decreased vibratory sensibility in toes (mean dose, 417 +/- 132 mg/m2 [SD]) and loss of ankle jerks (mean dose, 455 +/- 86 mg/m2). With continued therapy, four developed paresthesias. Strength was unaffected. Sural nerve responses abruptly disappeared in six of peripheral nerves from four patients showed axonal degeneration and secondary myelin breakdown. Platinum concentrations in three patients were similar in tumor (3.3 micrograms/g), sural nerves (3.5 micrograms/g), and spinal ganglia (3.8 micrograms/g), but lower in brain (0.17 microgram/g). This may explain the cisplatin toxicity of peripheral nerves with relative sparing of the central nervous system.