An altered heparan sulfate structure in the articular cartilage protects against osteoarthritis.

OBJECTIVE: Osteoarthritis (OA) is a progressive degenerative disease of the articular cartilage caused by an unbalanced activity of proteases, cytokines and other secreted proteins. Since heparan sulfate (HS) determines the activity of many extracellular factors, we investigated its role in OA progression. METHODS: To analyze the role of the HS level, OA was induced by anterior cruciate ligament transection (ACLT) in transgenic mice carrying a loss-of-function allele of Ext1 in clones of chondrocytes (Col2-rtTA-Cre;Ext1e2fl/e2fl). To study the impact of the HS sulfation pattern, OA was surgically induced in mice with a heterozygous (Ndst1+/-) or chondrocyte-specific (Col2-Cre;Ndst1fl/fl) loss-of-function allele of the sulfotransferase Ndst1. OA progression was evaluated using the OARSI scoring system. To investigate expression and activity of cartilage degrading proteases, femoral head explants of Ndst1+/- mutants were analyzed by qRT-PCR, Western Blot and gelatin zymography. RESULTS: All investigated mouse strains showed reduced OA scores (Col2-rtTA-Cre;Ext1e2fl/e2fl: 0.83; 95% HDI 0.72-0.96; Ndst1+/-: 0.83, 95% HDI 0.74-0.9; Col2-Cre;Ndst1fl/fl: 0.87, 95% HDI 0.76-1). Using cartilage explant cultures of Ndst1 animals, we detected higher amounts of aggrecan degradation products in wildtype samples (NITEGE 4.24-fold, 95% HDI 1.05-18.55; VDIPEN 1.54-fold, 95% HDI 1.54-2.34). Accordingly, gelatin zymography revealed lower Mmp2 activity in mutant samples upon RA-treatment (0.77-fold, 95% HDI: 0.60-0.96). As expression of major proteases and their inhibitors was not altered, HS seems to regulate cartilage degeneration by affecting protease activity. CONCLUSION: A decreased HS content or a reduced sulfation level protect against OA progression by regulating protease activity rather than expression.

Hiding opaque eyes in transparent organisms: a potential role for larval eyeshine in stomatopod crustaceans.

Opaque screening pigments are a fundamental requisite for preserving resolution in image-forming eyes. Possession of any type of image-forming eye in a transparent, pelagic animal will thus undermine the ability of that animal to be invisible in the water column. Transparent, pelagic animals must therefore deal with the trade-off between the ability to see and the ability of other animals to see them. Stomatopod larvae, like many transparent crustaceans, possess specialized optics in their compound eyes that minimize the volume of the opaque retina. Though the volumes of these retinas are reduced, their opacity remains conspicuous to an observer. The light reflected from structures overlying the retinas of stomatopod crustacean larval eyes, referred to here as eyeshine, is hypothesized to further reduce the visibility of opaque retinas. Blue or green wavelengths of light are most strongly reflected in stomatopod larval eyeshine, suggesting a putative spectral matching to the light environment against which the larval eyes are viewed. We tested the efficacy of stomatopod crustacean larval eyeshine as an ocular camouflaging mechanism by photographing larvae in their natural light environment and analysing the contrast of eyes with the background light. To test for spectral matching between stomatopod larval eyeshine and the background light environment, we characterized the spectrum of eyeshine and calculated its performance using radiometric measurements collected at the time of each photographic series. These results are the first to demonstrate an operative mirror camouflage matched in both spectrum and radiance to the pelagic background light environment.

c-myc in Kaposi's sarcoma: analyses by fluorescent in situ hybridization and immunohistochemistry.

BACKGROUND: The c-myc proto-oncogene plays a central role in the regulation of cellular transcription, differentiation, and apoptosis, and has been shown to be deregulated in many types of human cancer. Recent findings have demonstrated its amplification in select vascular neoplasms, such as secondary angiosarcomas, suggesting a role in angiogenesis as well. In vitro studies have shown that the c-Myc protein is an important regulatory molecule of spindle cell proliferation and migration in Kaposi's sarcoma (KS). OBJECTIVES: In light of these findings, our primary aim was to ascertain whether c-myc, by promoting proliferation and angiogenesis, is an essential co-factor in the aetiopathogenesis of KS. We also attempted to determine a correlation between immunohistochemical expression of the c-Myc protein and c-myc gene copy amplification using fluorescent in situ hybridization (FISH). METHODS: Samples analyzed included archival tissue of KS (n = 24). PCR for detection of Kaposi's sarcoma-associated herpesvirus DNA was performed on all samples of KS. For FISH analyses, a dual-labelled technique was employed and probes for the c-myc gene and chromosome 8 were used. The monoclonal anti-c-myc antibody, 9E10, was used for immunohistochemical analyses. RESULTS: While FISH analyses revealed no amplification of c-myc in any of the cases of KS, immunohistochemical analyses revealed positive staining for c-Myc in 13/24 cases (54%). CONCLUSIONS: Amplification of the c-myc gene was not witnessed in this preliminary study of 24 cases and thus cannot be correlated with the expression of the c-Myc protein.

Optical flow-cell multichannel immunosensor for the detection of biological warfare agents.

An automated optical flow cell multichannel immunosensor for the detection and identification of toxins, viruses and bacterial particles is presented. A solid phase ELISA, based on a peroxidase label for signal generation and on fused silica capillaries as a support for immobilized antibodies, has been employed for analyte detection and identification. The sensing and signal transducing component of the sensor consists of a light-emitting diode and a photodetector. The device is fitted with three channels allowing the simultaneous detection of three agents. An integrated flow injection analysis system ensures automation of the assay cycles. Data on the detection of the bacterial toxin staphylococcal enterotoxin B (SEB), the bacteriophage M13 as a viral agent, and Escherichia coli as a bacterial agent are presented.

Combination of microplate and miniplate for osteosynthesis of mandibular fractures: an experimental study.

Because of the limited space available in the mandible, especially in the mental foramen and apical region, miniature osteosynthesis material is desirable. Recently, metal deposition in the direct neighbourhood of osteosynthesis plates made of titanium or even in peripheral organs have been reported in the literature with increasing frequency. The size and amount of osteosynthesis material used should therefore be kept to a minimum. In an experimental study on 60 models, we examined load-carrying stability and in a second series, torsional strength of two-piece plastic models connected by either a single miniplate, two miniplates, or a titanium microplate plus a miniplate. In our test arrangement, the average loading capacity of the combination miniplate/miniplate was 470 N: that of the combination microplate/miniplate was only 267 N. The test group with the single miniplate had an average loading capacity of only 225 N. Masticatory loads on the plates exceeding 200 N occur only 3 months after osteosynthesis. At that time the fracture has largely consolidated. The torsional strength of the microplate/miniplate combination was similar to that of the miniplate/miniplate combination (1,000 Nmm resulting in a width of the gap measuring 0.8 mm and 0.5 mm, respectively). The single miniplate was considerably less stable (0.8 mm gap width as early as with 300 Nmm). According to Champy, rotational forces in the anterior region of the mandible amount to approximately 1,000 Nmm and need to be withstood by the osteosynthesis material. Our results suggest that treatment of fractures in the interforaminal region with a combination of microplate and miniplate will be stable enough for early mobilization.

Ectopic submandibular thyroid tissue with a coexisting active and normally located thyroid gland: case report and review of literature.

Ectopic thyroid tissue in the submandibular space with the thyroid gland in its normal location is an extremely rare phenomenon. We present a case of a 75-year-old woman who had painless swelling in the left submandibular space and was referred to our hospital with the suspicion of having a malignant tumor originating from the submandibular gland. Histologic examination showed normal follicular thyroid tissue without any sign of malignancy. In general there are 3 explanations for the presence of ectopic thyroid tissue found in the submandibular region: (1) displacement during the course of embryonal development, (2) spread of tissue during surgery on a normally located thyroid gland, and (3) metastasis of a highly differentiated papillary thyroid carcinoma. We reviewed the literature with respect to the embryological background and the clinical management of such cases.

A new method of blood sampling and determination of the local anesthetic agent lidocaine in dentistry.

Blood levels of local anesthetic agents after application in dentistry have been determined only in peripheral venous blood. A method of withdrawing blood from the alveolus after extraction of a tooth was developed. With a new simple gas chromatographic method with a low detection limit, concentration of lidocaine was determined. A correlation between the blood levels of lidocaine and the type of anesthesia and the localization of the extracted teeth was found.

A simple method for the determination of articaine and its metabolite articainic acid in dentistry: application to a comparison of articaine and lidocaine concentrations in alveolus blood.

This study was undertaken to develop a time- and cost-effective method for the detection of articaine and articainic acid in alveolus blood by high-performance liquid chromatography with a simple method of sample pretreatment. To overcome the problem of very rapid hydrolysis a method for controlling hydrolysis in vitro after blood sampling was developed. Blood samples were withdrawn from the alveolus of the upper molars 2-14 min after submucous injection of articaine (2.0 ml 4%) or identical injection of lidocaine (2.0 ml 2%). The higher blood levels found for articaine correspond to the higher concentration of the drug in the injection solution. A relationship between the serum concentration of articaine and lidocaine, respectively, and the time between injection and blood sampling could be established.

[The pharmacokinetic behavior of AWD 26-06 in humans following single and multiple administration]. / Untersuchungen zum pharmakokinetischen Verhalten von AWD 26-06 am Menschen nach ein- und mehrmaliger Gabe.

The pharmacokinetics of the muscarinolytic drug AWD 26-06 was investigated in two subjects after a single dose of 50 and 100 mg, respectively, and with six subjects after repeated dosage. The half time (t1/2) is 2.4 and 2.6 h, respectively, the height of the concentration maximum (Cmax) 500 and 1400 ng.ml-1, respectively, and the area under the curve (AUC) 2155 and 4334 ng.ml-1.h, respectively. The repeated dosage (25 mg every 8 h for 7 d) showed a small increase of the serum level. The t1/2 and the mean residence time (MRT) at the 1st and the 8th d are 2.6 h (range: 1.8-2.9 h) and 4 h (range: 2.7-5.8 h), respectively. The point (tmax) and the Cmax were not different at the 1st and 8th d: mean tmax (1st d) 1.1 h (range: 1.0-1.5 h), mean tmax (8th d) 0.9 h (range: 0.75-1.0 h); Cmax (1st d) 227 ng.ml-1 (range: 160-320 ng.ml-1), Cmax (8th d) 282 ng.ml-1 (range: 168-320 ng.ml-1). There were also no differences for the AUC0-t at the 1st and 8th d (1st d) 815 ng.ml-1.h (range: 610-1134 ng.ml-1.h). The simulation of the serum level by means of the data from the single dose were established by this investigation. Typical subjective muscarinolytic symptoms (e.g. dryness of the mouth, diminution of accommodation) were observed after the 2nd/3rd dosage. These signs diminished 24-36 h after discontinuation of the dosage. The parameter ALAT, proteins of plasma, and blood cell count were not changed at the end of therapy in comparison to the beginning.

Surgical and orthodontic rapid palatal expansion in adults using Glassman's technique: retrospective study.

In 1984, Glassman et al. described a conservative surgical method of separation of the midpalatal suture in which an osteotomy is done only at the lateral and anterior wall of the maxilla. Between 1991 and 1997, we have operated on 21 patients with maxillary transverse discrepancies using the method that they described. This gave good results in 20 patients. The other, who was operated on at the age of 38 years, developed a fracture of the alveolar process of the maxilla on one side because of ossification of the midpalatal suture. The surgically assisted rapid palatal expansion described by Glassman et al. is suitable for patients up to the age of 30. Older patients require additional surgical separation of the midpalatal suture.

[The concentration of local anesthetics in the dental alveolus. Comparative studies of lidocaine and articaine in the mandible and maxilla]. / Die Konzentration von Lokalanästhetika in der Zahnalveole. Vergleichende Untersuchungen von Lidocain und Articain im Unter- und Oberkiefer.

Lidocaine has been widely investigated as a local anaesthetic and cardiac antiarrhythmic agent. Articaine is the mostly used local anaesthetic agent in German dentistry. Blood levels of local anaesthetic agents after application in dentistry have been measured only in peripheral venous blood. Concentrations in the target region near the pain receptor have not been investigated. Therefore it seemed worth to compare the concentration of lidocaine and articaine in the upper and the lower jaw after extraction of a tooth as well as the penetration and distribution of the drug in the tissue and bone of the jaw. For this purpose a method for withdrawing blood from the alveolus after extraction of a tooth was developed. First patients were submitted to submucous injections of lidocaine (2.3 ml 2%) into the upper jaw and to mandibular block injection of lidocaine (2.0 ml 2%) into the lower jaw. Correlation between blood levels of lidocaine and the type of anaesthesia as well as the location of the extracted teeth were found. In the upper jaw very high concentrations of both anaesthetics were found and the blood levels of lidocaine in the region of incisors were higher compared to those in the region of molars. In the lower jaw the blood levels of lidocaine were on average ten times lower than in the upper jaw and the highest values were found in the region of molars. Secondly, blood samples were withdrawn from the alveolus of the upper molars 3 to 23 min after submucous injection of articaine (2.0 ml 4%) or identical injection of lidocaine (2.0 ml 2%).(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of photoreceptor cell types in the little brown bat Myotis lucifugus (Vespertilionidae).

We report the expression of three visual opsins in the retina of the little brown bat (Myotis lucifugus, Vespertilionidae). Gene sequences for a rod-specific opsin and two cone-specific opsins were cloned from cDNA derived from bat eyes. Comparative sequence analyses indicate that the two cone opsins correspond to an ultraviolet short-wavelength opsin (SWS1) and a long-wavelength opsin (LWS). Immunocytochemistry using antisera to visual opsins revealed that the little brown bat retina contains two types of cone photoreceptors within a rod-dominated background. However, unlike other mammalian photoreceptors, M. lucifugus cones and rods are morphologically indistinguishable by light microscopy. Both photoreceptor types have a thin, elongated outer segment. Using microspectrophotometry we classified the absorption spectrum for the ubiquitous rods. Similar to other mammals, bat rhodopsin has an absorption peak near 500 nm. Although we were unable to confirm a spectral range, cellular and molecular analyses indicate that M. lucifugus expresses two types of cone visual pigments located within the photoreceptor layer. This study provides important insights into the visual capacity of a nocturnal microchiropteran species.

Fluorescence studies of host-guest interaction of a dansyl amide labelled calix[6]arene.

The fluorescence behavior of a calix[6]arene with a dansyl group as fluorescence marker (C6-DA) was investigated with respect to the inclusion properties of alkaloids as atropine and cocaine. A strong hypsochromic shift of the fluorescence band and a strong increase in fluorescence intensity is connected with the interaction of atropine to the lower rim of the C6-DA. The fluorescence increase is saturated at an atropine concentration above the 1:1 complex formation. Addition of cocaine to the complexed atropine-C6-DA leads to a decrease of the fluorescence intensity which could be explained by an exchange mechanism of the complexed molecules. The complexation of the atropine (the "belladonna effect") is interpreted by electrostatic interaction (proton transfer from the carboxylic group to the nitrogen) with important contribution from hydrogen bonding by the guest OH-group.

Some aspects of pharmacokinetic and biotransformation differences in humans and mammal animals.

The erroneous tendency to set pharmacokinetics and biotransformation of drugs in man against results obtained in animals as a different homogenous group is discussed. Species differences have mainly a quantitative character, such as the body weight to surface ratio, organ weight to body weight ratio, presence of differing fat deposits, etc. Qualitative differences are not so common. The great importance of a better knowledge of these problems for the prediction of drug effects in man from results obtained in animals is emphasized.

[Kinetics of lithium]. / Zur Kinetik des Lithiums.

After administration of easily soluble or ready dissolved lithium salts two phases can be defined in the changes of the blood level, and three in the case of lithium salts with a lesser solubility in water. The first phase from the time 0 to tmax is denoted by a massive invasion into the blood, this is counteracted by the beginnings of absorption into the tissue and elimination through the kidneys. In the second phase the absorption into the blood is returned to a constant even distribution; the absorption in the tissue and renal excretion rise notably. When the distribution is completed, the renal excretion is dominant. The kinetics of lithium are independent of the salt used. The salt, however, because of its solubility in oral administration can influence the absorption kinetics, tmax and the absolute blood level. By using Li2CO3 with a suitable speed of solubility a depot effect can be shown.

[Clinico-pharmacologic studies with a M1 receptor antagonist (substance AWD 26-06) in a phase I clinical trial]. / Klinisch-pharmakologische Untersuchungen mit einem M1-Rezeptor-antagonisten (Substanz AWD 26-06) in der Stufe I der klinischen Erprobung.

The tolerability of the compound AWD 26-06 (which is to classify as a M1-antagonist in consequence of the pharmacological investigations) was investigated in 11 healthy male persons with increasing dosage from 5 to 150 mg. Dryness of the mouth and scratch in the throat were observed by a dosage of 50 mg onwards, a diminuation of the flow of saliva and the accommodation were observed by a dosage of 100 and 150 mg, respectively. The frequency of the heart, but not the blood pressure, is increased by 150 mg of AWD 26-06. The influence on the secretion of the gastric juice was investigated in normal conditions and after stimulation by Pentagastrin with a dosage of AWD 26-06 of 25 mg in comparison with a placebo on 7 healthy male persons. The volume of gastric juice was diminished by 35% in all fractions, but the secretion of HCl, measured as basal acid output and peak acid output, was diminished in 5 of the 7 persons by 20%. A further investigation in order to check the therapeutic effect in patients with ulcus ventriculi and ulcus duodeni, respectively, is necessary and useful.

On the distribution of drugs in saliva and blood plasma.

The equilibration of drug concentrations between blood plasma (unbound part) and saliva was studied for selected drugs with different physicochemical properties: Quinidine, sulfamerazine, paracetamol, diazepam and ethanol. From these and other experimental results it is suggested: 1. The concentration ratio between saliva and blood plasma (unbound) can only equal one for basic drugs with a pK a lower than 5.5 and acid drugs with a pK a higher than 8.5 and for pH indifferent drugs. 2. The drug must have a sufficient permeation ability through lipid membranes, valuable by the lipid water partition coefficient.