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.

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.

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.

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.

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.

[Glassman palatine expansion. Experiences with mono- and bimaxillary dysgnathia operations]. / Gaumennahtsprengung nach Glassman. Erfahrungen bei mono- und bimaxillaren Dysgnathieoperationen.

The median palatine suture has long been regarded as having the greatest resistance to dilatation of the maxilla. In 1984 Glassman [3] presented a conservative-surgical method of division of the palatineal suture in which only the lateral and anterior support of the maxilla is debilitated surgically. An orthodontic apparatus cemented in place preoperatively is already used intraoperatively for dilatation of the maxilla. In the period from 1991 to 1997, 16 patients with a leptomaxilla and various dysnathic findings have been operated on at our clinic by the method described by Glassman. Sometimes the maxilla was dilated intraoperatively using the apparatus cemented in place by the method of Derichsweiler and dilatation was continued post-operatively until the described result was achieved. After successful dilatation of the maxilla and a stabilizing phase, a mono- or bimaxillary operation was performed. The use of this method led to the desired result in 15 patients. Dilatation of the maxilla was objectivized by determining the pre- and postoperative width of the anterior and posterior dental arch using models and X-ray of the occlusal overlay of the maxilla. In one patient who was operated on at the age of 38 years, a fracture of the alveolar process of the maxilla occurred unilaterally due to the completed ossification of the median palatine suture. The method of surgically aided dilatation of the maxilla at the level of Le Fort I plane is suitable for patients up to the age of 30. In older patients, the median palatine suture should be transsected as well.

Influence of HPA-1a and HLA antibodies on primary hemostasis.

The influence of platelet specific and HLA antibodies was investigated on primary hemostasis by the in vitro bleeding test (IVBT) (Thrombostat 4000). Seven of 12 plasmas with HPA-1a (P1A1) antibodies and two with antibodies against glycoprotein Ib/IX significantly inhibited the IVBT of normal, cross-match-positive donor blood. This correlated with a significant increase of GMP-140 (CD 62) on the platelets, determined by flow cytometry. These results agree with the literature showing both activation and inhibition of platelet function by platelet specific antibodies. On the other hand, HLA antibodies showed a similar platelet activation (shortening of occlusion time and decrease in blood volume in the IVBT, increase of CD 62 expression) as plasma samples of polytransfused thrombocytopenic patients without HLA antibodies. It can be concluded that neither an activating nor an inhibitory effect of HLA antibodies on platelet function is significant in vivo. The IVBT seems not to be suited for compatibility testing.

[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)

[Effect of HPA-1a(PLA1) and HLA antibodies on platelet function, measured with the in vitro bleeding test]. / Einfluss von HPA-1a(PLA1)- und HLA-Antikörpern auf die Plättchenfunktion, gemessen mit dem In-vitro-Blutungstest.

The influence of platelet-specific and HLA antibodies on primary hemostasis was investigated by the in vitro bleeding test (IVBT). Seven of 12 plasmas with HPA-1a (PLA1) antibodies and two with antibodies against glycoprotein Ib/IX significantly inhibited the IVBT of normal cross-match-positive donor blood. This correlated with an increase of GMP-140 on the platelets determined by flow cytometry. Therefore the inhibition of the IVBT was interpreted to be due to rapid platelet activation by platelet-specific antibodies followed by an irreversible loss of function. In contrast, with HLA antibodies neither activation nor inhibition of the platelet function could be proven.

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.

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.

[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.

The influence of food on the absorption of diclofenac as a pure substance.

The interaction of diclofenac as a pure substance was investigated without and with concomitant administration of food in 8 healthy, male volunteers (age: 23-29 years, body weight: 60-87 kg). Diclofenac was given as a pure substance by means of a rapid dissolving capsule in a dose of 50 mg. Paracetamol (1.5 g), a marker of gastric emptying rate, was administered simultaneously with diclofenac in order to elucidate the influence of gastric emptying rate on diclofenac absorption. The bioavailability was determined according to the time (tmax) of the concentration maximum in plasma (Cmax) and the area under the curve (AUC). Food significantly delays tmax of diclofenac (without food: [mean +/- SD] 0.8 +/- 0.5 h, range: 0.5 +/- 2 h; with food: 2.4 +/- 0.9 h, range: 1.5-4 h) and diminishes Cmax (without food: 1,125 +/- 765 ng/ml, range: 95-2,100 ng/ml; with food: 434 +/- 151 ng/ml, range: 250-555 ng/ml). The AUC is not influenced (without food: 1,217 +/- 368 ng/ml x h; with food: 1,037 +/- 267 ng/ml x h). The bioavailability of paracetamol is unchanged. It is concluded that the diminishing of Cmax and the delay of tmax of diclofenac are possibly the consequence of an interaction with food and not of the delayed gastric emptying per se.

[Individually-adjusted dosages of aminophylline in children with bronchial asthma]. / Individuell angepasste Dosierung von Aminophyllin bei Kindern mit Asthma bronchiale.

Theophylline concentrations in serum between 10 to 20 micrograms/ml cannot be obtained with usual dosage of theophylline in children with individual very short elimination half time of theophylline. Multiple corrections of dosage and repeated controls of theophylline concentrations in serum are necessary for empirical adjustment of individual optimal dosage. Pharmacokinetic investigations were made to shorten this management. 12 patients with bronchial asthma, 6 to 18 years of age, received 1.5 to 3 tablets of Aminophyllin under conditions of steady state. Blood samples were taken up to 6 hours after oral application. As a result of statistical analysis we found that the biological half time of theophylline could be determined from 2 to 3 blood samples. Estimation of optimal individual dosage is possible by simple mathematical pharmacokinetic formulas.

The biliary elimination of the selective beta-receptor blocking drug talinolol in man.

The biliary elimination of the beta-1-receptor blocking agent talinolol was investigated after intravenous administration of 30 mg in 6 patients with a T-tube drain after cholecystectomy. Serum concentration decreased in a biexponential manner with a median terminal half-life time of 4.4 h (range: 3.0-6.2 h). In some patients a second peak of the serum level was found. Concentration-time curves in bile paralleled serum profiles. The bile:serum concentration ratio (b:s-ratio) ranged from 24 to 98. The biliary clearance amounted to 43 ml/h.kg (range: 13-212 ml/h.kg). The median of the amount of talinolol eliminated by bile was 2.8 mg (range: 1.1-7.4 mg). It is concluded that talinolol undergoes an enterohepatic circulation. However, the amount eliminated cannot provide a sufficient explanation for the second peak, observed in some patients.