Rabbit plasma fibronectin levels associated with Staphylococcus aureus enterotoxin B: an acute-phase reaction

Variation in fibronectin (Fn) levels and white blood cell counts (WBC) following staphylococcal enterotoxin B (SEB) or SEB + cryoprecipitate containing Fn challenge was studied in New Zealand white rabbits. Increased plasma Fn levels were observed 2 h after the intravenous injection of SEB and peaked at 48-72 h (from a mean level 194.6 +/- 4.5 micrograms/ml prechallenge Fn level to a 72-hour postchallenge mean level of 407.9 +/- 25.4 micrograms/ml). Fn levels then decreased over the succeeding 5 days to approximately prechallenge levels. The total WBC count decreased by 88% within 2 h after the SEB injection. A slow increase in circulatory WBC was observed over the next 24 h. SEB caused an increase in plasma Fn levels and decreased WBC counts with lymphopenia that was followed by a normal lymphocyte count within 5 days. These data suggest that an acute-phase reaction was induced by interleukin-1. Fn prophylaxis provided no change in clinical signs when given at the time of SEB injection.

Clinical significance of cerebrospinal fluid tests for neurosyphilis

From 1978 to 1987, 1,665 cerebrospinal fluid (CSF) fluorescent treponemal antibody absorption (CSF-FTA-ABS) tests were performed as the screening procedure for neurosyphilis. The CSF samples from 48 patients were reactive, and the medical history and results of the CSF-Venereal Disease Research Laboratory test (CSF-VDRL) for syphilis for 38 of these patients were reviewed. Likely active neurosyphilis was diagnosed if the patient had a reactive CSF-FTA-ABS test, recent onset of neurological signs consistent with neurosyphilis, abnormal CSF, and no other recognized cause for the neurological illness. Fifteen patients were so classified. Four had a reactive CSF-VDRL test. The specificity of the CSF-VDRL in diagnosing likely active neurosyphilis was 100%, but the sensitivity was only 27%. The insensitivity of the CSF-VDRL test limits its usefulness as a screening test for neurosyphilis. The CSF-FTA-ABS test appears more sensitive for screening but is less specific than the CSF-VDRL test in distinguishing currently active neurosyphilis from past syphilis. These findings imply that clinical judgment is still essential in establishing the diagnosis of active neurosyphilis.

Natural history of frequent recurrences of herpes simplex labialis

We prospectively studied all herpes simplex labialis (HSL) episodes in a group of 84 (age, 6 to 71 years) persons who previously had frequent recurrences of HSL to determine whether their recurrences of HSL were different from those of the general population. The mean +/- standard error for number of HSL outbreaks for 6 months was 2.7 +/- 0.3. Age, gender, or season did not influence the recurrence rate. The mean time to vesicle healing of 214 outbreaks was 6.4 +/- 0.2 days. Again, age or gender did not influence healing time. An episode of HSL did not elicit a refractory period to the next attack of HSL. Furthermore, the severity of the previous HSL lesion did not influence the interval to next recurrence or the location of the next lesion. In 47%, the next recurrence of HSL crossed the midline of the face, and in 45%, it moved from one lip to the other. The high recurrence frequency and multiple facial locations of HSL lesions seen in these persons differed from the general population, who report infrequent lesions of HSL at the same facial location.

Causes of death of patients in an institution for the developmentally disabled

The causes of death of 53 severely to profoundly developmentally disabled patients who died in an intermediate care facility were reviewed. Respiratory disease, predominantly pneumonia and aspiration, accounted for 72% of deaths. Seven patients died of nonrespiratory causes, and in 8 patients, no cause of death could be determined, even after a complete autopsy or investigation. The median age at death was 20 years. The weights of these patients' organs at autopsy were lower than those for normal individuals of the same age. The lifespan of these severely impaired individuals continues to be significantly shortened, even with improved methods of care.

Predictive model for plasma concentration-versus-time profiles of investigational anticancer drugs in patients

We report a model that provides a strong correlation between mouse toxicity data [mouse lethal dose 10% (LD10)] and human plasma concentration-versus-time (CXT) data for 22 commonly used anticancer agents. Mouse toxicity data (LD10) from two dosing schedules, daily times one and daily times seven, were evaluated for the two mouse strains BDF/1 and Swiss. Data from BDF/1 mice were selected for analysis because they were more abundant. Strong correlations were found between LD10 and human plasma CXT data for both daily times one and daily times seven dosing schedules--ln (CXT) = -1.6504 + [0.8408 X ln (LD10)], r = .84, P less than .0001, and ln (CXT) = -0.0754 + [0.8954 X ln (LD10)], r = .90, P less than .0001, respectively. These correlations may serve as useful models to predict the maximally tolerated dose of an investigational anticancer agent prior to entry into clinical trials and to assist in the selection of clinically relevant in vitro CXTs for new-agent screening against human tumors.

Pharmacokinetics of thiamylal in cats

Pharmacokinetics of thiamylal were determined after 13.2 mg of thiamylal/kg of body weight was administered IV to 6 healthy cats. Blood samples were obtained for 12 hours. Disposition of thiamylal best conformed to 2 multicompartmental models, a 2-compartment (n = 1) and a 3-compartment (n = 5) open pharmacokinetic model. The pharmacokinetic values were calculated for the overall best-fitted model, a mixed 2- and 3-compartmental model. The first or rapid distribution half-life was 1.91 minutes and a second, or slower, distribution half-life was 26.51 minutes. The elimination half-life was 14.34 hours. The apparent volume of distribution was 3.61 +/- 1.8463 L/kg, whereas the apparent volume of the central compartment was 0.46 +/- 0.2034 L/kg, and the total clearance was 0.135 +/- 0.0616 L/kg/h.

Hypothyroidism complicating pregnancy

Hypothyroidism rarely complicates pregnancy because most affected women are anovulatory. In this report, we describe 28 complicated pregnancies cared for over a ten-year period at Parkland Memorial Hospital. In the group of 16 pregnancies in 14 overtly hypothyroid women, maternal complications were common and included anemia (31%), preeclampsia (44%), placental abruption (19%), postpartum hemorrhage (19%), and cardiac dysfunction. Perinatal morbidity and mortality were also high mainly because of placental abruption, and reflected frequent low birth weight (31%) and fetal death (12%). In a group of 12 women with subclinical hypothyroidism, these complications were less impressive. We speculate that overt thyroid deficiency is associated with adverse pregnancy outcome related to preeclampsia and placental abruption. Thyroxine replacement probably improves these outcomes even if subclinical hypothyroidism persists.

Distribution of chloramphenicol in the genital tract of postpartum cows

Chloramphenicol was administered by constant IV infusion to 7 healthy postpartum cows at rates predicted to approach a steady-state plasma concentration of 5 micrograms/ml. After 8 hours of constant IV infusion, uterine tissues were removed surgically and were assayed for chloramphenicol concentrations. Mean plasma-to-tissue ratios of chloramphenicol concentrations were 3.05, 3.63 (6 cows only), and 3.22 for caruncles, endometrium, and uterine wall, respectively. Plasma-to-tissue ratios of the 3 tissues were not significantly different (P greater than 0.10). Intrauterine (IU) injections of chloramphenicol (20 mg/kg of body weight) were administered to 3 healthy post-partum cows. The mean value of the fraction of the drug absorbed from the uteri of these cows was 0.40. Mean concentrations of chloramphenicol were 43.8 micrograms/g in caruncles, 34.6 micrograms/g in endometrium, 2.8 micrograms/g in uterine wall, and 2.9 micrograms/ml in plasma 8 hours after IU injections. Chloramphenicol has now been banned for use in food-producing animals in the United States because of its potential for causing toxicosis in human beings. It is illegal to use chloramphenicol in food-producing animals in the United States and in some other countries as well. This includes use by the IU route of administration because chloramphenicol and most drugs are absorbed from the uterus into the bloodstream and are distributed to milk and tissues.

Peripartum heart failure in a patient treated previously with doxorubicin

Postpartum congestive heart failure developed in a primigravida seven years after doxorubicin therapy for osteosarcoma. Delayed cardiac toxicity may be affected by preeclampsia, anemia, or postoperative fluid management.

Inhibition of fatty acid beta oxidation by influenza B virus and salicylic acid in mice: implications for Reye's syndrome

Injection of concentrated influenza B/Lee/40 virus into 4-week-old Balb C mice resulted in 60% inhibition of 14C-palmitate oxidation in isolated hepatic mitochondria. Oral feeding of carnitine to infected mice prevented the inhibition of fatty acid oxidation. High concentrations of salicylic acid given orally also inhibited 14C-palmitate oxidation. Serum free fatty acid concentrations of infected mice and of those fed salicylic acid were significantly higher than in control mice. A combination of low-dose virus and low-dose salicylic acid inhibited palmitate oxidation, suggesting an additive effect on the metabolic derangement when the two agents were present simultaneously.

Tumor-associated blood group antigen expressions and immunoglobulins associated with tumors

As outlined in Figures 1 and 2, the biosynthetic pathways for the expression of the A, B and H, and the Lewis determinant carbohydrate sequence structures, as well as sialylated structures, involves both type 1 and type 2 precursor chains (which may be present as glycolipids and N- or O-linked glycoproteins), and many glycosyltransferases. For tumor cells, there appears to be increased expressions of fucosyl- and sialyltransferases yielding such structures as the Le(x), sialyl-Le(a), and many other similar determinants, which are not found on the normal cell progenitor of the tumor. The types of structures expressed on tumor cells is dependent on the particular fucosyl-, sialyl- and other glycosyltransferase genes activated in the transformation and tumor progression events, the availability of the substrates for the glycosyltransferases (both the precursor sequences and the nucleotide-sugar substrates) which is partly dependent on metabolites available to the tumor mass, and on the genotype of the individual regarding particular glycosyltransferases. Both the loss of A, B and/or H blood group antigen expressions of tumor cells and the relative expressions of the Lewis and sialylated-oligosaccharide determinants may be a consequence of the competing biosynthetic pathways and the glycosyltransferases for common substrate sequences, as well as due to the loss of particular glycosyltransferases concomitant with transformation. All of these factors probably account for the variable expressions of the complex of carbohydrate sequence determinants when comparing tumor sections of different individuals as well as the heterogeneity of expression of particular determinants within a single tumor tissue section. As described above, the A, B and/or H determinants, and the precursor sequences, are also expressed to differing extents on epithelial cells depending on the tissue type and cellular location in the tissue. Thus, the differentiation state of the particular epithelial cell also determines the quantity and types of carbohydrate sequences expressed. However, because of the complex nature of the competing biosynthetic pathways for the carbohydrate sequences of glycolipids and glycoproteins, and the relative activations of fucosyl- and sialyltransferases of tumor cells, it would seem that simple deductions as to the state of differentiation of particular tumors with A, B, H and precursor sequence expressions is not warranted.(ABSTRACT TRUNCATED AT 400 WORDS)

Florfenicol in non-lactating dairy cows: pharmacokinetics, binding to plasma proteins, and effects on phagocytosis by blood neutrophils

Serial blood samples were collected and plasma concentrations of florfenicol (FLO) were measured following the administration of an intravenous bolus of 50 mg/kg FLO to five healthy non-lactating dairy cows. A triexponential equation provided the best fit of the data for four of the five cows. The mean value for beta corresponded to a half-life of 3.2 h. The mean apparent volume of distribution was 0.67 l/kg, and the mean body clearance was 0.15 l/kg/h. The extent of binding of FLO to bovine plasma proteins was determined in vitro at concentrations of 5 micrograms/ml and 50 micrograms/ml by equilibrium dialysis and ultrafiltration. The drug was 18% and 19% bound by equilibrium dialysis, and 23% and 19% bound by ultrafiltration, at 5 micrograms/ml and 50 micrograms/ml, respectively. Phagocytosis of 32phosphorus-labelled Staphylococcus aureus by bovine blood neutrophils was compared in vitro between neutrophils incubated in phosphate-buffered saline alone or in combination with 5, 125, or 1000 micrograms/ml chloramphenicol or FLO. There was no significant effect of chloramphenicol at any concentration. Florfenicol significantly inhibited phagocytosis at all concentrations, but the percentage inhibition was small. The clinical significance, if any, of this effect of FLO remains to be demonstrated.

Recovery and probable persistence of cytomegalovirus in human inner ear fluid without cochlear damage

Cytomegalovirus (CMV) was recovered from a 5-month-old infant with probable congenital infection. In life, no hearing impairment had been observed. Auditory brain stem evoked responses were bilaterally intact. At necropsy, both temporal bones were morphologically normal, as demonstrated by light and electron microscopy. Sensory hair cells of the organ of Corti appeared intact. Cytomegalovirus was recovered from a mixture of perilymph and endolymph, but not the brain, CSF, or vitreous humor. This appears to be the first report of an individual with an inner ear CMV infection in which neither structural nor functional alterations of the inner ear were apparent. This case also suggests that CMV can persist within the inner ear for prolonged periods following congenital infection.

Disposition of fenbendazole in cattle

Fenbendazole (FBZ) was administered to cattle IV and orally in a crossover design. Plasma concentration vs time profiles were reported for FBZ and its major metabolites, the sulfoxide (oxfendazole) and the sulfone. The total excretion of FBZ and its metabolites in urine and feces was also measured for 6 days after administration. All known metabolites were identified in urine and feces except for fenbendazole amine. Neither this minor metabolite nor p-hydroxyfenbendazole (FBZ-OH) appeared in plasma. The major excretory product was FBZ-OH. After oral administration, only 44.6% of the dose was eliminated after 6 days, indicating a fairly high degree of sequestration, probably within the gastrointestinal tract.

Effect of organic vehicles on the pharmacokinetics of aminophylline administered intravenously to goats

Aminophylline dissolved in water, propylene glycol, or dimethyl sulfoxide was administered intravenously to goats in a randomized cross-over experiment. Model-dependent and model-independent pharmacokinetic parameters for theophylline were compared on the basis of the solvent used in the dosage form administered. No difference was found in any pharmacokinetic parameter. Thus, we found no evidence for the possibility that the organic solvents studied would confound pharmacokinetic investigations of theophylline and similar lipophilic drugs.

Disposition of fenbendazole in the goat

The disposition of fenbendazole was studied in goats after oral or IV administration. Plasma concentration vs time profiles were determined for fenbendazole and all of its metabolites. The total excretion of the drug and its metabolites in urine and feces was also measured for 6 days. A biliary cannula was inserted in 1 goat to study the excretion of fenbendazole and its metabolites into the bile. Fenbendazole was converted to its sulfoxide (oxfendazole), and the sulfone, primary amine, and p-hydroxylated metabolites. The active metabolite, oxfendazole, appeared in plasma, but only trace amounts were found in feces or urine. The major excretory metabolite was p-hydroxyfenbendazole.

Adverse drug reactions in the horse

Adverse drug reactions occasionally occur in the horse. The majority can be anticipated and avoided. The practicing veterinarian should understand the various types of adverse reactions as well as their mechanisms so that should such a reaction occur, the practitioner can promptly recognize the problem and institute corrective measures.

Influenza B virus model of Reye's syndrome. Evidence for a nonpermissive infection of liver and brain

Nonpermissive or abortive viral infections seldom have been recognized as damaging to organs. Concentrated infectious influenza B/Lee virus injected intravenously into Balb/c mice causes a microvesicular fatty metamorphosis of the liver and produces many features of Reye's syndrome. Evidence for a nonpermissive infection in brain and liver includes the following points: (a) no viral replication occurs in either organ; (b) no inflammation develops; (c) no virions are seen by electron microscopy; (d) influenza B viral hemagglutinin increases in the liver; (e) immunofluorescent and immunoperoxidase staining demonstrate viral antigens within hepatocytes and brain capillary endothelial cells; (f) viral antigens appear at 12 hours and disappear by 4 days without spread to adjacent cells; (g) inactivated influenza B virus does not kill mice; (h) mouse alpha- and beta- interferon and homologous B/Lee antiserum given before but not 2 hours after virus inoculation protects mice. These observations suggest a nonpermissive viral infection in hepatocytes and brain capillary endothelial cells which is important in the pathogenesis of the mouse illness and may play a role in the pathogenesis of Reye's syndrome.

Procainamide in the dog: antiarrhythmic plasma concentrations after intravenous administration

Procainamide hydrochloride was administered to ouabain-intoxicated dogs to determine an antiarrhythmic plasma concentration of procainamide. Ventricular arrhythmias were produced in dogs following intravenous injections of ouabain. After a sustained ventricular tachycardia was achieved, procainamide was administered and plasma samples collected for assay. Plasma procainamide was assayed by fluorescence polarization immunoassay. Procainamide was administered at increasingly higher constant rate infusions in order to achieve intermittent, steady-state plasma concentrations. Infusion rates were calculated on the basis of previous pharmacokinetic information. All six dogs that received procainamide converted to a normal sinus cardiac rhythm after attaining a mean plasma concentration of 33.8 micrograms/ml with a range of 48.5 micrograms/ml-25.0 micrograms/ml. It was observed that the computer-generated prediction of plasma concentrations based upon previous pharmacokinetic data produced an underestimate of the actual plasma concentrations. These data may suggest that plasma concentrations of procainamide for controlling some cardiac arrhythmias in dogs may be higher than plasma concentrations cited for human patients.

A fatal variant of human ornithine carbamoyltransferase is stimulated by Mg2+

Biochemical studies of a female who died at 2 years of age from a possible genetic variant of ornithine carbamoyltransferase (OCTase) deficiency are reported. The patient had severe psychomotor retardation with plasma ammonia levels throughout life reaching as high as 500 mumole/liter. The average OCTase level in the patient's liver was 2% of that in normal livers. Preincubation with 0.05 M MgCl2 resulted in a 570% increase in OCTase activity (13% of control). Citrate synthase and carbamoyl-phosphate synthase I were present at essentially normal levels. Unusual Mg2+ requirements have not been recognized in previous reports of OCTase deficiency, suggesting a genetic variant in this patient.

Photochemical linking of primary aromatic amines to carrier proteins to elicit antibody response against the amine haptens

Two chemical methods, diazocoupling and reaction with isocyanates, are commonly used to conjugate primary aromatic amines with carrier proteins in order to elicit antibody responses against the aromatic amine haptenic group. Limitations of these conjugation techniques include the requirement for specific functional groups on the carrier protein which generally limits the degree of haptenic substitution obtainable, the many possible side reactions yielding hapten-hapten and carrier-carrier conjugates which waste valuable materials and lower desired hapten-carrier conjugate yields, and, in some cases, conjugation conditions which may denature the carrier protein (e.g., alkaline coupling conditions). We report here a photolabeling approach for conjugating primary aromatic amines to carrier proteins which avoids some of the problems of other conjugation methods and which was used to elicit antibodies against the primary aromatic amine hapten. The method described here is of general application for coupling primary aromatic amines to the carrier proteins and circumvents many of the problems inherent in the isocyanate or diazocoupling methods. 3-Azido-N-ethylcarbazole (ANEC), the azido analog of 3-amino-N-ethylcarbazole, was conjugated to bovine serum albumin (BSA), human transferrin (TR), thyroglobulin (TH), poly-(lysine X tyrosine), and poly-(lysine X phenylalanine) using standard photolabeling procedures. After photolysis, the conjugated proteins or polypeptides were separated from the unbound products of ANEC photolysis on a Sephadex G-10 column. The conjugated proteins were extracted with isobutanol which demonstrated that approximately 20% of the ANEC was covalently coupled to the protein carriers and that the larger portion of the aromatic haptens was non-covalently and hydrophobically bound to the carriers. The ANEC-protein conjugates used for immunization demonstrated a total covalently and non-covalently bound ANEC epitope density of 90 per BSA, 107 per TR and 800 per TH molecule. Rabbits were immunized with the three conjugated proteins and the production of antibody specific for the 3-amino-N-ethylcarbazole hapten was demonstrated by enzyme-linked immunosorbent assay and by inhibition studies using hapten-carrier conjugates of free hapten. The results demonstrate that antibodies against aromatic amine haptens may be raised by immunizing animals with hapten-carrier protein conjugates produced by photolabeling. Since the coupling conditions are very mild and the functional group requirements are so general (requiring only the presence of C-H, N-H, C = O, C = S, or S-H bonds) most carrier proteins should be suitable for use in this method.(ABSTRACT TRUNCATED AT 400 WORDS)