House dust mite counts in different types of mattresses, sheepskins and carpets, and a comparison of brushing and vacuuming collection methods

Mite counts were compared in dust from three types of mattreses. Foam rubber mattresses appear preferable for mite sensitive atopic subjects; the surface of kapok mattresses averaged twice, and innerspring mattresses three times, the number of mites per square metre found on foam rubber mattresses (P < 0.01). Sheepskins used for infant bedding were also found to be heavily infested, harbouring as many mites per square metre as bedroom carpet. Mite collections are best made with vacuum sampling methods in preference to a brush and results are best expressed in mites/m².     

Intranasal DDAVP induced increases in plasma von Willebrand factor alter the pharmacokinetics of high-purity factor VIII concentrates in severe haemophilia A patients

Because native circulating factor VIII (FVIII) is maximally stabilized when it is bound to von Willebrand factor (vWf), increased plasma vWf levels may enhance the infused FVIII concentrate intravascular survival and efficacy in severe haemophiliacs. To assess whether the kinetic characteristics and recovery of high purity, plasma-derived (Monoclate-P, Centeon) and recombinant (Bioclate , Centeon) FVIII concentrates are enhanced by increased plasma vWf concentrations, we compared the pharmacokinetic response to a bolus of FVIII infused alone with the response to a bolus infused 2 h after the intranasal delivery of 300 microg of desmopressin acetate (DDAVP) High Concentration Nasal Spray (Stimate, Centeon) in 10 adult severe haemophiliacs. FVIII activity was determined using a one-stage clotting assay on cryopreserved plasma specimens obtained at baseline and at 14 distinct time points (0.25-48 h) following the FVIII infusions. Ristocetin co-factor activity (RCoFA) and vWf antigen levels were assayed at baseline and 2 h after Stimate. FVIII kinetic parameters were calculated using standard, noncompartmental kinetic methods. Statistical analysis was performed using a paired t-test with 95% confidence limits. The mean rises in RCoFA (0.65+/-0.44 IU mL(-1)) and vWf antigen (0.19+/-0.07 IU mL-1) induced by Stimate were significant (P<0.01 and P<0.0001, respectively). The mean increases in the volume of distribution at steady state (Vss) (13.2+/-9.3 dL) and mean residence time (MRT) (4.4+/-3.9 h) between the FVIII-only arm and the FVIII plus Stimate arm were highly significant (P = 0.0015 and P = 0. 0059, respectively). The mean differences in recovery, area under the curve (AUC), half-life, and clearance (Cl) were not significantly altered. Subgroup analysis revealed statistically significant increases in Vss and MRT (P = 0.025 and P = 0.012, respectively) following the administration of intranasal DDAVP in the Monoclate-P cohort, but not in the Bioclate group. These data suggest that even modest pharmacologically induced increases in plasma vWf can favourably affect the kinetics of high-purity, plasma-derived FVIII concentrates in severe haemophiliacs.     

INDICATIONS FOR ADMISSION TO THE SURGICAL INTENSIVE CARE UNIT AFTER RADICAL CYSTECTOMY AND URINARY DIVERSION

PURPOSE: We analyzed the practice of mandatory surgical intensive care unit admission after radical cystectomy, and defined objective criteria to predict active treatment requirements and surgical intensive care unit stay. MATERIALS AND METHODS: We retrospectively reviewed the records of 115 consecutive patients admitted to the surgical intensive care unit after radical cystectomy and urinary diversion during the 36-month study period of January 1996 to December 1998. An Acute Physiology and Chronic Health Evaluation II score was calculated from postoperative patient parameters at admission to the unit. Active treatment mandating admission was defined as postoperative invasive cardiopulmonary monitoring, administration of vasopressors or inotropic medications, monitoring or treatment for life threatening complications, or mechanical ventilation for longer than 12 hours. We analyzed the correlation of outcome variables with the requirements for active treatment and surgical intensive care unit stay, and developed a stratification model of low versus high risk. Low risk was defined as a calculated likelihood of less than 10% for requiring active treatment postoperatively. RESULTS: Mean stay in the surgical intensive care unit plus or minus standard error was 34.4 +/- 3.1 hours. No active treatment was required in 63.5% of patients during the stay. The evaluation score, intraoperative complications and number of intraoperative transfusions were the strongest predictors of required postoperative active treatment. By combining these variables we developed a clinically applicable algorithm to stratify patients into a low and a high risk category. In patients at low and high risk the active treatment rate was 5.9% and 42.8% (p = 0.001), and the mean stay was 24.6 +/- 2.2 and 38.7 +/- 4.5 hours (p = 0.039), respectively. CONCLUSIONS: Mandatory surgical intensive care unit admission of all patients after radical cystectomy and urinary diversion does not appear indicated. A subset of patients at low risk for requiring active treatment may be identified who may be safely treated in an intermediate care setting after initial postoperative observation in the recovery room. The results of our retrospective analysis and risk stratification model should be validated in a prospective trial.     

Selenium, rubidium and zinc in human semen and semen fractions

The levels of selenium, rubidium and zinc were determined in samples of semen, seminal plasma and spermatozoa from men with suspected infertility, together with several parameters of semen quality. The proportion of whole semen selenium present in sperm increased with increasing sperm count from 0 to 40%. For rubidium 98 +/- 4% and for zinc 95 +/- 8% of the total amount in semen was contained in seminal plasma. In seminal plasma a positive correlation was found between the levels of zinc and selenium, and between the levels of zinc and rubidium, indicating that, like zinc, selenium and rubidium in seminal plasma also derive mainly from the prostate gland. Semen quality parameters, such as sperm motility, vitality, speed and morphology, were not correlated with the contents of the three elements in either whole semen or seminal plasma. As the seminal content of selenium is dependent on the proportion of prostatic secretion in seminal plasma and on the sperm count, and both factors can vary considerably, the selenium level of whole semen does not appear to be a suitable parameter for investigation of the relationship between selenium and semen quality. Provisional measurements suggest lower sperm selenium levels at abnormally low or high sperm counts.     

Developmental Toxicity of Dinitroaniline Herbicides in Rats and Rabbits

The potential developmental toxicity of trifluralin was evaluatedin rats and rabbits. Pregnant rats and rabbits were dosed oncedaily by gavage on Gestation Days 6–15 and 6–18,respectively. Doses for rats were 0, 100, 225, 475, or 1000mg/kg; doses for rabbits were 0, 100, 225, or 500 mg/kg. Cesareansections were performed on rats and rabbits on Gestation Days20 and 28, respectively. In rats, maternal toxicity was indicatedin the 475 and 1000 mg/kg treatment groups by depression ofbody weights and food consumption. Fetal viability and morphologywere not adversely affected at any dose level. Developmentaltoxicity was indicated at the 1000-mg/kg dose level by depressionof fetal weight. The NOAEL for maternal toxicity in the ratwas 225 mg/kg the NOAEL for developmental toxicity in the ratwas 475 mg/kg. In rabbits, maternal toxicity was indicated atthe 225 and 500 mg/kg dose levels by abortions and/or deathsin conjunction with anorexia and cachexia. Developmental toxicitywas indicated at the 500 mg/kg dose level by depressed fetalviability and weight. Fetal morphology was not adversely affectedat any dose level. The NOAELs for maternal and developmentaltoxicity in the rabbit were 100 and 225 mg/kg, respectively.Based on these data, trifluralin did not exhibit selective toxicitytoward the developing conceptus.     

Cutaneous nodular sarcoidosis with granulomatous renal sarcoid

We describe a 66-year-old lady who presented with tender nodules on her trunk and limbs which were histologically proved to be sarcoid. Following steroid therapy the skin lesions remitted, but renal failure developed due to a severe granulomatous interstitial nephritis. Clinical and biochemical improvement followed treatment with high dose steroids, although renal function and renal biopsy remained abnormal.     

Selective Induction and Inhibition of Renal Mixed Function Oxidases in the Rat and Rabbit

Selective Induction and Inhibition of Renal Mixed Function Oxidasesin the Rat and Rabbit. Rush, G.F., Wilson, D.M. and Hook, J.B.(1983). Fundam. Appl. Toxicol.. 3:161-168. Renal mixed functionoxidases vary in response to inducers depending on the species.Pretreatment of rabbits with ß-naphthoflavone(100mg/kg x 4days) or pheno-barbital (60 mg/kg x 4 days) resultedin a highly selective induction of renal microsomal ethoxyresorufin-O-deethylaseand benzphetamine-N-demethylase, respectively. Pretreatmentof rats with ß-naphthoflavone (100 mg/kg) inducedrenal microsomal ethoxyresorufin and ethoxycoumarin-deethylationwhereas phenobarbital (80 mg/kg) was without effect. Furthermore,benzphetamine-N-demethylase could not be detected in rat renalmicrosomes. These data suggest that the composition of renalcytochromes P-450 may vary between species. -Naphthoflavoneinhibited both ethoxyresorufin and ethoxycoumarin metabolismby rat and rabbit renal microsomes; inhibition was highly selectivefor renal microsomes from ß-naphthoflavone-treatedanimals. Metyrapone did not inhibit rat renal microsomal mixedfunction oxidases from any treatment group. In contrast, rabbitrenal microsomal xenobiotic metabolism from all treatment groupswere strongly inhibited by metyrapone. Furthermore, polyacrylamidegel electrophoresis of solubilized renal microsomes from rabbitstreated with phenobarbital revealed a new coomassie blue stainingband in the range of 50000–60000 daltons; no such patternwas observed in rats. Electrophoresis of solubilized renal microsomesfrom both rats and rabbits treated with ß-naphthoflavonerevealed increased Coomassie blue staining. It is apparent fromthese results that the rat kidney lacks any phenobarbital inducibleform of cytochrome P-450 and that rat renal microsomes containat least two forms of cytochrome P-450 whereas rabbit renalmicrosomes contain at least three forms.     

The Immunotoxicity of Three Nickel Compounds following 13-Week Inhalation Exposure in the Mouse

The Immunotoxicity of Three Nickel Compounds following 13-WeekInhalation Exposure in the Mouse. HALEY, P. J. SHOPP, G. M.,BENSON, J. M, CHENG, Y.-S., BICE, D. E., LUSTER, M. I., DUNNICK,J. K., AND HOBBS, C. H. (1990). Fundam. Appl. Toxicol 15, 476–487.Groups of B6C3F₁, mice were exposed to aerosols of nickel subsulfide(Ni₃S₂), nickel oxide (NiO), or nickel sulfate hexahydrate (NiSO₄6H₂O)6 hr/day, 5 days per week for 65 days to determine the immunotoxicityof these compounds. Exposure concentrations were 0.11, 0.45,and 1.8 mg Ni/m³ for Ni₃S₂, 0.47, 2.0, and 7.9 mg Ni/m³ forNiO; and 0.027, 0.11, and 0.45 mg Ni/m³ for NiSO₄. Thymic weightswere decreased only in mice exposed to 1.8 mg Ni/m³ Ni₃S₂. Increasednumbers of lung-associated lymph nodes (LALN), but not spleennucleated cells, were seen with all compounds. Nucleated cellsin lavage samples were increased in mice exposed to the highestconcentrations of NiSO₄ and NiO and to 0.45 and 1.8 mg Ni/m³Ni₃S₂. Increased antibody-forming cells (AFC) were seen in LALNof mice exposed to 2.0 and 7.9 mg Ni/m³ NiO and 1.8 mg Ni/m³Ni₃S₂. Decreased AFC/10⁶ spleen cells were observed in miceexposed to NiO, and decreased AFC/spleen were seen for miceexposed to 1.8 mg Ni/m³ Ni₃S₂. Only mice exposed to 1.8 mg Ni/m³Ni₃S₂ had a decrease in mixed lymphocyte response. All concentrationsof NiO resulted in decreases in alveolar macrophage phagocyticactivity, as did 0.45 and 1.8 mg Ni/m³ Ni₃S₂. None of the nickelcompounds affected the phagocytic activity of peritoneal macro-phages.Only 1.8 mg Ni/m³ Ni₃S₂ caused a decrease in spleen naturalkiller cell activity. Results indicate that inhalation exposureof mice to nickel can result in varying effects on the immunesystem, depending on dose and physicochemical form of the nickelcompound. These nickel-induced changes may contribute to significantimmunodysfunction.