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Mucosal in vitro permeability in the intestinal tract of the pig, the rat, and man: species- and region-related differences

BACKGROUND: The barrier properties of the gastrointestinal mucosa may be studied by measuring its permeability to different-sized marker molecules. Owing to difficulties in obtaining human tissue it is, however, often necessary to extrapolate findings from experimental animals to man. The aim of the present study was to compare regional intestinal mucosal permeability in man, the rat, and the pig,

The macrophage migration inhibitory factor MIF is a phenylpyruvate tautomerase

A macrophage migration inhibitory factor (MIF), originally described as a product of activated lymphocytes, has been defined as a 12 kDa protein, expressed in a wide variety of tissues. Here MIF is identified as a phenylpyruvate tautomerase (EC 5.3.2.1) having p-hydroxyphenylpyruvate and phenylpyruvate as its natural substrates. The definition of MIF as an enzyme may yield insight into the mechani

Teaching ancient folklore

Finely wrought pieces of storytelling, pithy sayings and clever riddles constituting oral traditions often labelled “verbal art” abound in ancient texts. Yet while it has long been recognised that such traditions—folklore—can be found in the Homeric poems, it is less well known that they have also been incorporated into many other types of texts. This paper aims to offer a concise description of h

Alignment of valence photoemission, x-ray absorption, and substrate density of states for an adsorbate on a semiconductor surface

A method for determining the placement of x-ray absorption data into an experimental density of states for an adsorbate-semiconductor system is motivated and illustrated with the cases of bi-isonicotinic acid, isonicotinic acid, and benzoic acid on rutile TiO2(110). Special attention is paid to experimental aspects, as well as the role of Z+1 effects and the choice of reference level.

A heterogeneous population of alpha 1-adrenoceptors mediates contraction of the isolated follicle wall from the bovine ovary

Strips from Graafian follicles of bovine ovaries were tested for their contractile response in vitro in order to characterize the type of post-junctional alpha-adrenoceptor involved. Electrically induced contractions were inhibited concentration-dependently by the alpha 1-antagonist, prazosin. Besides noradrenaline the alpha 1-selective agonists, methoxamine and phenylephrine, caused the strips to

Antibody to hepatitis-C-virus-related proteins in sera from alanine-aminotransferase-screened blood donors and prospectively studied recipients

A prospective study of posttransfusion non-A, non-B hepatitis was conducted in Malmo, Sweden, in 1984-1985, in which donors were alanine aminotransferase (ALT) screened but not ALT selected. Among 741 patients studied at 0, 6, and 12 weeks after transfusion, 13 developed non-A, non-B hepatitis, and these were further followed up. Stored sera from the 13 hepatitis patients and their 123 donors were

Paradoxical stimulation of glucagon secretion by high glucose concentrations

Hypersecretion of glucagon contributes to the dysregulation of glucose homeostasis in diabetes. To clarify the underlying mechanism, glucose-regulated glucagon secretion was studied in mouse pancreatic islets and clonal hamster In-R1-G9 glucagon-releasing cells. Apart from the well-known inhibition of secretion with maximal effect around 7 mmol/l glucose, we discovered that mouse islets showed par

Photochemistry of diiodomethane in solution studied by femtosecond and nanosecond laser photolysis. Formation and dark reactions of the CH2I-I isomer photoproduct and its role in cyclopropanation of olefins

Femtosecond and nanosecond photolysis of CH2I2 in acetonitrile at an excitation wavelength of 266-nm yield the ground-state CH2I-I isomer product in similar to70% quantum yield. High isomer formation quantum yields (> 70%) were measured also in n-hexane, dichloromethane, methanol, and ethanol using nanosecond photolysis. The CH2I-I product is formed biphasically within similar to15 ps after excita

In vivo absorbed dose measurements in mammography using a new real-time luminescence technique

A dosimetry system based on radioluminescence (RL) and optically stimulated luminescence (OSL) from carbon doped aluminium oxide (Al2O3:C) crystals was developed for in vivo absorbed dose measurements in mammography. A small cylindrical crystal of Al2O3:C (diameter 0.48 mm and length 2 mm) was coupled to the end of a 1 mm diameter optical fibre cable. Owing to their small size and characteristic s

A Detailed Kinetic Model for Calculation of the Soot Particle Size Distribution Function

The soot particle size distribution was studied via numerical simulation under diesel like engine conditions using a detailed kinetic soot model. Two different mathematical methods of the soot model description have been used in this work. In the first part of the work, the method of moments is presented. In addition, a so called sectional method for the soot particle size distribution function in

Development of a solid-phase extraction method for the determination of polychlorinated biphenyls in water

Polychlorinated biphenyls (PCBs) in water were extracted with a rebuilt extraction unit using 47 mm C18 solid-phase extraction (SPE) disks. Three types of disks (SPEC, ENVI and Empore) were investigated for the extraction of seven PCBs from 1 l reagent water spiked at two concentration levels (20 and 1000 ng/l). The Empore disks produced the best analyte recoveries (91–107% with R.S.D. of 1–8%) at

Det manliga klimakteriet: om försöket att lansera ett medicinskt begrepp

Är du en surgubbe?” frågar kvällstidningen Aftonbladet i en artikelrubrik. I så fall kan du ha hamnat i det manliga klimakteriet. Allt oftare talas det idag om ett manligt klimakterium. Ämnet väcker allmänhetens uppmärksamhet. Därigenom vinner föreställningen om att män i medelåldern drabbas av besvär och förlorar sin ’manlighet’ i en nedbrytande klimakterieprocess utbredning i samhället. Tanken p

Monitoring of persistent organic pollutants (POPs): Examples from Lake Vattern, Sweden

Lake Vattern in southern Sweden is a large oligotrophic lake with high surface to catchment area ratio (ca. 0.4) and a water residence time of 60 years. The lake combines sensitivity to atmospheric POP-pollution with general susceptibility for effects of POPs and slow concentration decline. Time series, from the 1960s until 1996, of PCBs and DDT in fish and data on TCDD in sediment of L. Vattern a

Eclampsia in Scandinavia: incidence, substandard care, and potentially preventable cases

Background. Description of incidence, clinical signs, symptoms, and consequences of eclampsia in Scandinavia, and assessment of substandard care and potential preventability. Methods. A descriptive cohort study including all women giving birth in a 2-year period (mid-1998-mid-2000) in Scandinavia. Notifications of eclampsia cases were obtained from all obstetric units at 3-monthly intervals. All p

Biosensors for life quality - Design, development and applications

Biosensors, combining a selective biological recognition element and a sensitive transducer, are versatile analytical tools applied more and more in different fields, such as medicine, food quality and safety control, and environment pollution monitoring. They are expected to play an increasingly important role in the improvement of life quality. In this context, the present work covers recent app

Synthesis of naphthoxylosides on solid support

In order to investigate the selective antiproliferative effects shown by 2-(6-hydroxynaphthyl)-beta-D-xylopyranoside the 14 possible beta-D-xylopyranosidic compounds were synthesized on solid support. An aminomethylated polystyrene resin was converted into an acid chloride resin and then esterified using dihydroxynaphthalene. The free hydroxy group was then xylosylated Under BF3.OEt2 mediated cond