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A novel, compact arrangement for Ka-band mode couplers, which convert a rectangular waveguide TE(1,0) to cylindrical waveguide TE(2,1) mode, has been designed, constructed, and tested. The design features a set of longitudinal slots, positioned in regions of negligible current flow for the TE(2,1) mode, allowing its propagation to be preferentially favored, by suppression of the fundamental TE(1,1) mode. Numerical simulations and experimental measurements display good agreement, showing transmission of the intended TE(2,1) mode at levels of better than -5 dB, from a frequency of ∼37.5 to 41 GHz. Subsequent farfield measurements confirm the presence of the TE(2,1) mode, demonstrating good agreement when compared with analytical expectations. Such a device would be an ideal candidate for an application where mode purity, bandwidth, and ease of construction are of primary importance and where the transmission efficiency is of limited concern.

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A group of 19 individuals who had been infected with methicillin-resistant Staphylococcus aureus (MRSA) and placed in source isolation were interviewed about their views of MRSA infection and the experience of source isolation. Participants were unclear about the nature of MRSA, and generally did not perceive the infection to have a significant impact upon their life (either in terms of the presence of symptoms or in restriction of activities). Despite this, roughly half the sample thought that an MRSA infection was 'serious'. Only one participant clearly viewed their MRSA as hospital-acquired, most being uncertain about the mode of transmission or viewing it as unrelated to the behaviour of care staff. Few respondents displayed an accurate knowledge of the reasons for source isolation and barrier nursing. Isolation was viewed as having advantages and disadvantages. There was little evidence of a detrimental psychological effect of isolation. Patients infected with MRSA appear to understand little about their condition or the necessity for barrier nursing and source isolation. This has implications for understanding patients' adherence with infection control procedures.

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High-performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE) were used in biodegradation kinetic studies. This paper describes a rapid penciclovir separation using CZE with detection limits comparable to HPLC. The ionic-strength mediated stacking technique was employed while good resolution was maintained. With a shorter analysis time, comparable detection limits and no organic solvent consumption, CZE is a better method for penciclovir biodegradation studies than conventional reversed-phase HPLC (RP-HPLC).

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BACKGROUND: Occupational allergic respiratory symptoms in coffee workers have been frequently reported, but the ultimate cause of sensitization is still debated, castor bean being considered besides green coffee beans. Atopy and cigarette smoking have been suggested as promoting factors of sensitization for several occupational allergens. OBJECTIVE: This study was carried out to assess the prevalence of allergic respiratory symptoms and of sensitization to both green coffee beans and castor bean in the whole workforce of a coffee manufacturing plant. Furthermore we wanted to ascertain both the presence of castor bean antigens in the settled dust of the green coffee beans warehouse and the possible crossreactivity between the two beans. Meanwhile, the effect of smoking and atopy was considered. METHOD: Two-hundred and eleven workers were examined. A questionnaire on oculorhinitis and asthma was administered and skin-prick tests for green coffee beans, castor bean and 15 common inhalant allergens were carried out. Isoelectric focusing, isoelectric focusing immunoblot and radioallergosorbent assay (RAST) inhibition were performed on samples of settled environmental dust from the green coffee area, as well as on castor bean and green coffee beans. RESULTS: Ten per cent of the workers complained of oculorhinitis alone and 16% of asthma (nearly always associated with oculorhinitis). The overall prevalence of skin-sensitization was: 15% for green coffee beans, 22% for castor bean, 22% for common allergens. Evidence of sensitization to occupational allergens was more common in smokers, with a more than twofold increase in relative risk. The strong association between skin positivity to common and occupational allergens suggests that atopy acts as an enhancing host factor towards occupational sensitization. The analysis of the dust confirmed the presence of castor bean antigens. CONCLUSION: Our findings indicate that castor bean is the major cause of occupational sensitization among coffee workers, whereas smoking and atopy act as enhancing factors.

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1. Beagle dogs dosed orally with 14C-tazadolene succinate excreted much of the dose in the urine (mean 63.1% in 5 days with most excreted in the first 24 h). A lesser proportion of the dose was excreted in the faeces (mean 20.7%) and again most of this was voided in the first 24 h. 2. Four metabolites were identified and quantified in the urine, namely 3-hydroxy-(M1), 4-hydroxy- (M2a), and 3-methoxy-4-hydroxy-tazadolene (M2b) and N-[2-(phenylmethylene)cyclohexyl]-beta-alanine (M3). 3. In the 24 h urine, M2a and b glucuronides accounted for 17.7% dose, unconjugated M2a and b for 11.3%, and M3 for 18.3%. Insufficient M1 was present to be quantified. The same metabolites were seen in the 24 h faeces, but at lower concn. Thus M2a and b glucuronides, M2a and b, and M3 were 3.2%, 4.9% and 3.5% dose respectively. 4. All three phenols were present in plasma as their glucuronides as well as the beta-alanine derivative. They all had the same tmax of 2 h and t1/2 lambda 1 of the order of 1 h.

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1. The pharmacokinetics and fate of 3H-trospectomycin sulphate, a novel aminocyclitol antibiotic, were examined in male and female rats after intramuscular (i.m.), intravenous (i.v.) and subcutaneous (s.c.) dosing. 2. Total radioactivity levels in plasma were associated with unchanged trospectomycin. Two radioactive components were found in urine, one was indistinguishable from trospectomycin and the other was probably a degradation product formed after excretion or during storage rather than a metabolite. 3. The disappearance of drug from plasma followed a biphasic pattern with half lives of 0.3-0.4 h and 45-80 h and a large distribution volume, which indicated some retention of drug by tissues. Clearance rates were within the normal range for glomerular filtration rate, which indicated that the primary process of elimination is filtration of unchanged drug. 4. Excretion was initially rapid (greater than 40% by 4 h) and mainly into urine (faecal excretion greater than 20%). Urinary excretion was significantly larger in males than females but faecal excretion was significantly smaller, so that there was no significant difference in total excretion. 5. The bioavailability following s.c. dosing was only approximately 75% but there were few other biologically significant differences between the routes of administration. Absorption following i.m. and s.c. dosing was rapid. 6. Clearance rate and volume of distribution were higher in males than females. Over the dose range 50-200 mg/kg the pharmacokinetics appeared to be mostly linear.

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The pharmacokinetics and fate of [3H]trospectomycin sulfate, a novel aminocyclitol antibiotic, were examined in male and female dogs and rabbits. Total radioactivity levels in plasma were associated with unchanged trospectomycin in both dog and rabbit. No unchanged drug was found in rabbit urine. Two radioactive components were found in dog urine; one was indistinguishable from trospectomycin and the other was probably a degradation product. The disappearance of drug from plasma followed a biphasic pattern and was well described by a bi-exponential function with half-lives of 0.4-0.8 and 30-70 hr in the dog and 0.4 and 90-120 hr in the rabbit. There was a large distribution volume (Vss), which indicated some retention of drug by tissues. The clearance (CL) for both animals was within the normal range for glomerular filtration rate. CL and Vss were not different between the sexes in the dog or rabbit. Excretion in both animals was initially rapid (greater than 40% by 4 hr) and mainly by the urinary route (fecal excretion less than 10%). Urinary excretion was not significantly different between the sexes. Over the dose range of 25-100 mg/kg, the plasma pharmacokinetics in the dog were linear. However, the recovery of radioactivity in the urine was significantly reduced at the highest dose. Trospectomycin CL in rat, human (obtained from previous studies), dog, and rabbit was described by the allometric equation, CL (ml/hr) = 132 x M0.91 where M is the body mass in kg.

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By virtue of familiarity and usage over many years, diagnostic tests may become established and be regarded as infallible "Gold Standards". In the case of allergic disease no test except perhaps allergen challenge can ever precisely reflect the clinical disease at the actual site of the allergic reaction. Thus when a new test is introduced there are no fixed values available for statistical comparison when directly comparing established tests with more recent additions. This is illustrated by many articles comparing the new multiple allergosorbent test system (CLA, MAST) which is a chemiluminescent assay, to other previously established tests. The major reports on CLA in the diagnosis of allergy are here discussed and summarized. Most trials have compared the accuracy of CLA with clinical history, with the skin prick test (SPT), the universally used in vivo method, or with RAST, the most common in vitro diagnostic method. CLA performed similarly to SPT and most CLA and RAST results matched; nevertheless in statistical analyses the problems of comparing diagnostic methods without a Gold Standard against which to judge become obvious-if two fallible methods disagree, which is correct? These statistical problems are discussed as well as other difficulties, such as the impact of the use of different allergen sources and the differing prevalence of allergies in the various test populations analysed.

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A simple high-performance liquid chromatographic method has been developed for detection and quantification of brodifacoum in plasma and liver tissue. After adding difenacoum as the internal standard, brodifacoum and difenacoum are extracted from 2 mL of plasma with two sequential 10-mL volumes of acetonitrile-ethyl ether (9:1) and from 2 g of liver tissue by grinding the tissue with 10 mL acetonitrile. The extracts are evaporated to dryness under nitrogen, 2 mL of acetonitrile is added to reconstitute the residues, and the resulting solution is analyzed using reversed-phase chromatography and fluorescence detection. The limits of detection for plasma and tissue are 2 micrograms/L and 5 ng/g, respectively. Using internal standardization, the mean intra-assay recovery from plasma is 92% and the mean inter-assay recoveries is 109%. The mean intra-assay and inter-assay recoveries from tissue are 96%. No interferences were observed with any of the following related compounds: brodifacoum, bromadiolone, coumarin, difenacoum, diphacinone, warfarin, and vitamin K1.

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Trospectomycin sulfate is an experimental, aminocyclitol antibiotic. It has been shown in preclinical, chronic safety studies in the dog and rat to elicit a reversible, lysosomal phospholipidosis in liver. The present experiments were conducted to characterize the tissue distribution and disposition of 3H]trospectomycin sulfate in the male rat, perfused rat, perfused rat liver, and cultured rat hepatocytes. Following a 5 mg/kg iv dose to four rats, approximately 70% of the dose was recovered within 24 hr primarily in urine as unchanged drug, and the remainder was eliminated with a terminal phase half-life in blood and tissues of 3 days. Fecal excretion was relatively minor (16% of the dose recovered in feces in 7 days) until later timepoints, when it was the principal pathway of terminal phase elimination. The liver sequestered approximately 10% of the dose and had the highest tissue levels of drug at all times measured. Liver perfusion experiments indicated that trospectomycin accumulated in a hepatic depot compartment as parent drug by a first-order process which was nonsaturable up to a 1 mM concentration of drug. Biliary excretion of unchanged trospectomycin by the perfused liver was slow (approximately 3% of the dose in 2 hr) and occurred by both paracellular and transcellular mechanisms. The hepatic depot compartment appeared to be responsible for transcellular biliary excretion, and thus for the sustained fecal excretion observed in vivo. Subcellular distribution experiments indicated that at least 50% of the drug in the hepatic depot was sequestered in organelles having a broad density range. The existence of a trospectomycin depot compartment was also demonstrated in cultured hepatocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

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Metabolism of tazadolene (1), a novel non-opioid analgesic with antidepressant properties, affords the 4-hydroxy and 3-methoxy-4-hydroxy derivatives (phenyl ring) of the drug, and N-[2-(phenylmethylene)cyclohexyl]-beta-alanine (4). The isolation, identification and synthesis of the latter metabolite is described.

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