Identification of volatile metabolites from five fungal species cultivated on two media

Five fungal species, Aspergillus versicolor, Penicillium commune, Cladosporium cladosporioides, Paecilomyces variotii, and Phialophora fastigiata, were cultivated on two media, malt extract agar and dichloran glycerol agar. Culture flasks provided with inlet and outlet tubes were used and purified, and humidified air was constantly led through the flasks. Air samples from the cultures were sorbed on Tenax GR and analyzed by thermal desorption-gas chromatography. The produced volatile metabolites were analyzed by mass spectrometry. Various hydrocarbons, alcohols, ketones, ethers, esters, sulfur-containing compounds, and terpenes were identified. The most commonly produced substances were 2-methyl-1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methylfuran, and dimethyl disulfide. The production was highly dependent on both medium and species.

High serum phytosterol levels in short bowel patients on parenteral nutrition support

BACKGROUND & AIMS

Patients with short bowel syndrome (SBS) are often depending on parenteral nutrition support (PNS), sometimes complicated by liver dysfunction. Phytosterols in parenteral lipid emulsions have been suspected to be responsible for cholestasis in paediatric nutrition support. The aim of the present study was to evaluate phytosterol intake and serum phytosterol levels in adult SBS patients.

METHODS

We quantified serum levels of phytosterols, cholesterol, and markers for bile acid and cholesterol synthesis, by gas or liquid chromatography in 21 healthy controls, and in 24 adult SBS-patients, 8 with and 16 without PNS. Phytosterols and cholesterol in parenteral lipid emulsions were also quantified.

RESULTS

Serum levels in SBS-patients without PNS; with PNS; and in controls, were on average for phytosterols 11; 63; and 23 micromol/l (P<0.05 for differences), cholesterol 4,2; 3,8; and 5,1 mmol/l, lathosterol 808; 824; and 228 micromol/100 mmol cholesterol, and 7alpha-hydroxy-4-cholesten-3-one 207;191; and 18 nmol/l, respectively (P<0.05 between controls and SBS). Phytosterols in lipid emulsions ranged from 591 to 958 micromol/l.

CONCLUSIONS

SBS-patients on PNS have higher serum levels of phytosterols than other SBS-patients and controls, possibly because of phytosterols in lipid emulsions. Patients with SBS, regardless of nutrition support, have lower serum levels of cholesterol but higher cholesterol and bile acid synthesis compared to controls.

Attitudes and barriers to dietary advice aimed at reducing risk of type 2 diabetes in first-degree relatives of patients with type 2 diabetes

OBJECTIVE

To evaluate the attitudes to and adoption of dietary advice in nondiabetic first-degree relatives of patients with type 2 diabetes and to examine barriers to adherence.

DESIGN

One-year controlled intervention study, where treatment group (n=73) received lifestyle education. Attitudes towards dietary advice, change in dietary habits and importance of potential barriers to adherence were evaluated by questionnaires. Nondiabetic relatives (25-55 years; males and females) of individuals with type 2 diabetes were recruited. Education was based on current nutrition recommendations and aimed at improving dietary fat quality, increasing intake of fruit and vegetables, with additional advice to reduce dietary glycaemic index (GI).

MAIN OUTCOME MEASURES

Attitudes and importance of barriers were classified by the intervened subjects into four categories ranging from 'No problem' to 'Yes, definitely a problem'. Dietary adherence was monitored by food frequency questionnaire at baseline and after 1 year.

RESULTS

Participants were generally in favour of advice aimed at improving dietary fat quality. Attitudes towards advice to reduce GI varied widely. Food selection changed in accordance with predefined dietary goals. 'Forgetfulness', 'low availability in lunch restaurant' and 'lack of ideas for cooking' were barriers to adherence.

CONCLUSIONS

Dietary advice aimed at reducing risk of type 2 diabetes was generally positively received and adopted in subjects with heredity for the disease. The most prevalent barriers reported are potentially modifiable.

Laser-triggered high-voltage plasma switching with diffractive optics

High-power lasers can be used to induce ionization of gases and thereby enable rapid triggering of electrical discharge devices, potentially faster than any devices based on mechanical or solid-state switching. With diffractive optical elements (DOEs) the laser light can conveniently be directed to positions within the gas so that an electrical discharge between two high-voltage electrodes is triggered reliably and rapidly. Here we report on two different types of DOE used for creating an electrical discharge in pure argon for potential high-voltage applications. One is the diffractive equivalent of a conventional axicon that yields an extended, and continuous, high-intensity focal region between the electrodes. The other is a multiple-focal-distance kinoform--a DOE that is designed to produce a linear array of 20 discrete foci, with high peak intensities, between the electrodes. We show that DOEs enable efficient, rapid switching and may provide increased flexibility in the design of novel electrode configurations.

Atmospheric atomic mercury monitoring using differential absorption lidar techniques

Three-dimensional mapping of atmospheric atomic mercury has been performed with lidar techniques, to our knowledge, for the first time. Industrial pollution monitoring, as well as measurements of background concentrations, is reported. High-efficiency frequency doubling of narrowband pulsed dye laser radiation was employed to generate intense radiation at the mercury UV resonance line. Field measurements were supplemented with extensive laboratory investigations of absorption cross sections and interfering lines of molecular oxygen.

NO plume mapping by laser-radar techniques

Mapping of NO plumes by using laser-radar techniques has been demonstrated with a mobile differential absorption lidar system. The system was equipped with a narrow-linewidth Nd:YAG-pumped dye laser that, with doubling and mixing, generated pulse energies of 3-5 mJ at 226 nm, with a linewidth of 1pm. This permitted range-resolved measurements of NO, with a range of about 500 m. The detection limit was estimated to 3 microg/m(3), with an integration interval of 350 m. Spectroscopic studies on the gamma(0, 0) bandhead near 226.8 nm were performed with 1-pm resolution, and the differential absorption cross section was determined to be (6.6 +/- 0.6) x 10(-22) m(2), with a wavelength difference of 12 pm.

Differential optical absorption spectroscopy system used for atmospheric mercury monitoring

A high-resolution differential optical absorption spectroscopy (DOAS) system for long-path atmospheric pollution monitoring is described. The system, consisting of a broadband lamp and a dispersive, fast-scanning optical receiver, separated by a few kilometers, was used in measurements of different pollutants, highlighted by the monitoring of the local concentration of atomic mercury. Mercury levels in the ppt (1:10(12)) range were assessed by comparisons with laboratory measurements.