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An 11-year-old Warmblood gelding with chronic bilateral epistaxis was diagnosed with an adenocarcinoma of the right ethmoid, based on transendoscopic biopsy. On computed tomography images, the cribriform plate was considered intact and the tumour was minimally invasive in surrounding tissue. The palliative treatment included a combination of surgical exploration and laser ablation. Following recurrence of the clinical signs one month later, intralesional formalin injection was performed. In the immediate post injection period, the horse developed severe neurological signs. Because of the overall poor prognosis, the horse was subjected to euthanasia. On post mortem examination, changes were seen in the frontal lobe consistent with diffusion of formalin through the cribriform plate. Care is needed when treating horses with intralesional formalin because macroscopic appearance of the cribriform plate may not relate to its functionality. [ABSTRACT FROM AUTHOR]

Antibiotic loading of bone regenerative materials is a promising way to protect augmentation procedures from infection during the resorption phase of bone substitutes. Especially in the early stage of implantation, it should protect the grafted site against microbiological pathogens. The present study reports the release kinetics of gentamicin after loading from two synthetic bone filling materials. The first, BONITmatrix®, is a biphasic calcium phosphate silica composite obtained by the sol–gel route consisting of 13% silicon dioxide (w/w) and calcium phosphates (hydroxyapatite/β‐tricalcium phosphate 60/40 w/w). The second, Synthacer®, is a sintered hydroxyapatite ceramic. Gentamicin was loaded by dipping and by vacuum coating. Release kinetics of the loaded Gentamicin was investigated by fluorescence polarization immunoassay and by staphylococcus aureus assay. By dipping, loading failed for Synthacer, and it was 12.7 mg gentamicin per gram bone substitute for BONITmatrix. By vacuum coating, loading was 11.3 mg gentamicin per gram bone substitute for Synthacer and 7.4 mg gentamicin per gram bone substitute for BONITmatrix. Distinct release kinetics were measured. For Synthacer, a high initial release was followed by a lower protracted release level up to 28 days. For BONITmatrix release was continuous over the investigated 70‐day period. The present data suggest that the porosity properties at the nano‐ and microscopic levels, or the composition are responsible for antibiotic loading and subsequent release. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [ABSTRACT FROM AUTHOR]

Naber D, Riedel M, Klimke A, Vorbach E-U, Lambert M, Kühn K-U, Bender S, Bandelow B, Lemmer W, Moritz S, Dittmann RW. Randomized double blind comparison of olanzapine vs. clozapine on subjective well-being and clinical outcome in patients with schizophrenia.Acta Psychiatr Scand 2005: 111: 106–115.© Blackwell Munksgaard 2004.This randomized double-blind multicenter trial evaluated the effects of olanzapine vs. clozapine on subjective well-being, quality of life (QOL) and clinical outcome.The primary objective was to demonstrate non-inferiority of olanzapine, mean dosage 16.2 ± 4.8 (5–25 mg/day) vs. clozapine, mean dosage 209 ± 91 (100–400 mg/day) regarding improvement on the‘Subjective Well-Being under Neuroleptic Treatment’ (SWN) Scale after 26 treatment weeks in 114 patients with schizophrenia. Secondary outcome parameters included: Munich QOL Dimension List (MLDL), Positive and Negative Symptom Scale (PANSS), Clinical Global Impression (CGI).SWN scores improved significantly in both groups, olanzapine was non-inferior to clozapine (group difference 3.2 points in favor of olanzapine; 95% CI: 4.2;10.5). MLDL-satisfaction, PANSS and CGI-S improved similarly, olanzapine yielded a higher CGI Therapeutic Index. Individual SWN and PANSS changes correlated only moderately (r = −0.45).Olanzapine was non-inferior to clozapine. The lack of a marked correlation between PANSS and SWN improvements indicates that patients and psychiatrists perceive treatment differently. [ABSTRACT FROM AUTHOR]

Between December 1996 and October 1997, milk samples from a total of 145 cows with coli mastitis were screened for the presence of verotoxin-producing E. coli (VTEC). VTEC were found in four (2.8 %) out of the 145 samples. The four isolated strains proved to be verotoxin (VT) 1-, VT2- or VT1- and VT2-positive. However, no strain contained all three virulence factors tested. Further strain characterization was carried out by serotyping as well as by resistance pattern analysis. [ABSTRACT FROM AUTHOR]

The triple-helical collagen molecule of vertebrates consists of two or three non-identical polypeptide chains: [(α1)2(α2)] or [(α1)(α2)(α3)]. We have attempted to form molecules from three identical chains: (α1)3 or (α2)3. The yield of (α1)3-molecules obtained after renaturation of α1 from calf or rat skin collagen and the yield of [(α1)2(α2)]molecules after renaturation of unfractionated collagen from both species is almost the same. (α1)3-molecules are able to form fibrils of the native type and long-spacing segments. Their melting temperature of approximately 34° is only slightly less than that of native molecules. in contrast the (α2)3-molecule is much less stable with a melting range of 20-24°. Therefore, (α2)3-molecules are formed at lower temperatures and with a lower yield than (α1)3- and [(α1)2(α2)]molecules. Renaturation experiments with a mixture of α1 and α2 (ratio 2:1) shows that the reformation of the [(α1)2(α2)]molecule is favoured over the (α1)3-molecule, in spite of the fact that both molecule have almost the same stability. Long-spacing segments from (α1)3, (α2)3 or native [(α1)2(α2)]molecules exhibit a similar if not identical cross- striation pattern in the electron microscope. Therefore, the conclusion can be drawn that the α1 and α2 chains are homologous. [ABSTRACT FROM AUTHOR]

Collagenase was found to attack the collagen molecule at both ends at 10°. Six molecular fragments of different lengths were observed and could be correlated with the intact molecule as long-spacing segment fragments. It was possible to isolate the 2,600, 1,250 and 780 Å fragments by fractional ammonium sulphate precipitation. The sharp helix-coil transition on denaturation shows that the fragments have an intact triple helix. It was possible to separate the two shorter fragments into three components (the α1, α2 and α3 chain fragments) by chromatography on CM cellulose. The α1 and α3 chains have very similar amino acid compositions and peptide maps for both these fragments. This suggests that the differences between these two components are probably due to telopeptides and not to the amino acid sequence of the main chain. [ABSTRACT FROM AUTHOR]

After dosing rats with gold thiosulphate a hardening of the collagen can be observed that is attributed to cross-linkage of the fibrils by the gold ion. Initially no reaction takes place between gold thiosulphate and collagen in vitro. Only after the central gold ion is set free by oxidative destruction of the thiosulphate groups can it enter into a coordination complex with the side-chain groups, forming new intermolecular bonds. In vivo the gold complex is apparently first taken up into the fibril by virtue of electrostatic forces. In a second slower reaction the thiosulphate groups are displaced by the side chain groups resulting in the cross-linkage. [ABSTRACT FROM AUTHOR]

The behaviour of rat skin collagen on collagenase treatment is analogous to that of calf skirt collagen. Fragments are also formed, but differ to a certain extent in length and amount from those by calf skin collagen. All molecular fragments consist, of only two electrophoretically separable chains, namely α1 and α2. [ABSTRACT FROM AUTHOR]

Objective: Cell-matrix interactions regulate chondrocyte differentiation and survival. The alpha1beta1 integrin is a major collagen receptor that is expressed on chondrocytes. Mice with targeted inactivation of the integrin alpha1 gene (alpha1-KO mice) provide a model that can be used to address the role of cell-matrix interactions in cartilage homeostasis and osteoarthritis (OA) pathogenesis., Methods: Knee joints from alpha1-KO and wild-type (WT) BALB/c mice were harvested at ages 4-15 months. Knee joint sections were examined for inflammation, cartilage degradation, and loss of glycosaminoglycans (by Safranin O staining). Immunohistochemistry was performed to detect the distribution of alpha1 integrin, matrix metalloproteinases (MMPs), and chondrocyte apoptosis., Results: In WT mice, the alpha1 integrin subunit was detected in hypertrophic chondrocytes in the growth plate and in a subpopulation of cells in the deep zone of articular cartilage. There was a marked increase in alpha1-positive chondrocytes in the superficial and upper mid-zones in OA-affected areas in joints from old WT mice. The alpha1-KO mice showed more severe cartilage degradation, glycosaminoglycan depletion, and synovial hyperplasia as compared with the WT mice. MMP-2 and MMP-3 expression was increased in the OA-affected areas. In cartilage from alpha1-KO mice, the cellularity was reduced and the frequency of apoptotic cells was increased. These results suggest that the alpha1 integrin subunit is involved in the early remodeling process in OA cartilage., Conclusion: Deficiency in the alpha1 integrin subunit is associated with an earlier deregulation of cartilage homeostasis and an accelerated, aging-dependent development of OA.

Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the progressive loss of dopaminergic neurons in the substantia nigra. Although valuable animal models have been developed, our knowledge of the aetiology and pathogenic factors implicated in PD is still insufficient to develop causal therapeutic strategies aimed at halting its progression. The neurotoxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is one of the most valuable models for analysing pathological aspects of PD. In this paper we studied the gene expression patterns underlying the pathogenesis of MPTP-induced neurodegeneration. We treated young and old C57BL/6 mice with different schedules of MPTP to induce degenerative processes that vary in intensity and time-course. During the first week after intoxication we used nonradioactive in situ-hybridization to investigate the expression patterns of genes associated with (i) dopamine metabolism and signalling; (ii) familial forms of PD; (iii) protein folding and (iv) energy metabolism. MPTP injections induced different severities of neuronal injury depending on the age of the animals and the schedule of administration as well as a significant degeneration in the striatum. In situ hybridization showed that MPTP intoxication initiated a number of gene expression changes that (i) were restricted to the neurons of the substantia nigra pars compacta; (ii) were correlated in intensity and number of changes with the age of the animals and the severity of histopathological disturbances; (iii) displayed in each a significant down-regulation by the end of one week after the last MPTP injection, but (iv) varied within one MPTP regimen in expression levels during the observation period. The subacute injection of MPTP into one-year-old mice induced the most severe changes in gene expression. All genes investigated were affected. However, alpha-synuclein was the only gene that was exclusively up-regulated in MPTP-treated animals displaying cell death.

Objective: The receptor activator of nuclear factor kappaB (RANK) is a member of the tumor necrosis factor receptor family. It is activated by the secreted or cell surface-bound RANK ligand (RANKL). Osteoprotegerin (OPG) is a soluble nonsignaling receptor for RANKL and interferes with RANK activation. This receptor-ligand system regulates the differentiation of osteoclasts and dendritic cells. The present study examined human articular cartilage for the expression of these molecules and the role of RANKL in the regulation of chondrocyte function., Methods: Normal and osteoarthritic (OA) human articular cartilage was used for explant tissue culture or for isolation of chondrocytes and cell culture. Expression of RANK, RANKL, and OPG was analyzed by immunohistochemistry, Western blotting, or reverse transcription-polymerase chain reaction. Recombinant RANKL was added to cartilage or chondrocyte cultures, and gene expression, collagenase and nitric oxide production, and NF-kappaB activation were determined., Results: RANK, RANKL, and OPG messenger RNA (mRNA) were expressed in normal cartilage. By immunohistochemistry, RANK, RANKL, and OPG were detected in the superficial zone of normal cartilage. OA cartilage contained increased levels of OPG mRNA, and expression of the 3 proteins extended into the midzone of OA cartilage. OPG was detected by Western blotting, and was increased in response to interleukin-1beta stimulation. OPG, RANK, and RANKL protein were also detected in cultured chondrocytes. Addition of exogenous RANKL did not activate NF-kappaB, induce expression of genes encoding proinflammatory mediators in chondrocytes, or stimulate the production of collagenase and nitric oxide., Conclusion: These results demonstrate the expression of OPG, RANK, and RANKL in cartilage. However, RANKL does not activate human articular chondrocytes.

Objective: To examine the role of nuclear factor kappaB (NF-kappaB) and caspases 3, 8, and 9 in CD95-mediated apoptosis of normal chondrocytes., Methods: First-passage chondrocytes from normal human knee cartilage were stimulated with CD95 antibody, and cell death was determined by annexin V binding and by an enzyme-linked immunosorbent assay. Activation of caspases 3, 8, and 9 was measured by Western blotting, and their role in death signaling was evaluated using caspase-specific small peptide inhibitors. The influence of NF-kappaB was determined by electrophoretic mobility shift assay (EMSA) and proteasome inhibition-dependent blocking of the degradation of inhibitor of NF-kappaB., Results: Low levels of NF-kappaB activity were detected by EMSA in unstimulated chondrocytes. NF-kappaB activity was increased in response to agonistic CD95 antibody. CD95 antibody-induced apoptosis was potentiated by the proteasome inhibitors MG-132 and PS1, and this was associated with a reduced nuclear translocation of NF-kappaB. Proteasome inhibitors also caused the induction of DNA fragmentation by tumor necrosis factor alpha. Procaspase 3 processing was enhanced by the proteasome inhibitor MG-132. Procaspase 8 was undetectable by immunoblotting in whole cell lysates of chondrocytes, but caspase 8 messenger RNA was detected by reverse transcription-polymerase chain reaction. Furthermore, apoptosis induced by CD95 stimulation and proteasome inhibitors was blocked by the caspase 8-specific inhibitor Ac-IETD-CHO. Processing of procaspase 9 was not observed, and inhibition of CD95-dependent cell death by the caspase 9 inhibitor Ac-LEHD-CHO was not significant., Conclusion: These results suggest that CD95-dependent cell death is enhanced by NF-kappaB inhibition at and/or downstream of caspase 8 activation and that caspase 9 activation is not involved in CD95-mediated apoptosis in chondrocytes.

Mutations in a protein designated Parkin were shown to be involved in the pathogenesis of autosomal recessive juvenile parkinsonism. Nothing is known about its regional and subcellular distribution in the mouse. In order to elucidate the Parkin mRNA and protein distribution in the adult mouse, the mouse cDNA was cloned and polyclonal antisera were generated against the N-terminal part of mouse Parkin. The antibodies were shown to be specific using Western blot analysis, immunostaining of cells transfected with mouse Parkin and pre-absorption tests. The Parkin protein expression profile was studied using immunohistochemistry and Western blot analysis and was compared with that of the mRNA yielded by in situ hybridization and RT-PCR analysis. Parkin protein was widely distributed in all subdivisions of the mouse brain. Low levels were found in the telencephalon and diencephalon, while the brainstem contained a large number of cells heavily expressing Parkin. Ultrastructural analysis and double immunohistochemistry revealed that the majority of Parkin-expressing cells were neurons, while only single glial cells exhibited immunostaining. The protein was distributed nonhomogeneously throughout the entire cytoplasm. A subpopulation of Parkin-immunopositive cells displayed speckled immunodeposits in the nucleus. Dopaminergic cells of the substantia nigra pars compacta exhibited high levels of Parkin mRNA but no Parkin protein, while the striatum contained immunopositive profiles but no mRNA signals. Our data indicate that Parkin is neither restricted to a single functional system nor associated with a particular transmitter system. The speckled nuclear distribution of Parkin immunoreactivity strongly suggests a role for Parkin in gene expression.