Prolyl and lysyl hydroxylases in collagen synthesis

Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases.     

The proteome microenvironment determines the protective effect of preconditioning in cisplatin-induced acute kidney injury

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Neurological disorders and violence: a systematic review and meta-analysis with a focus on epilepsy and traumatic brain injury

The objectives of this study were to systematically review and meta-analyze the research literature on the association of common neurological disorders and violence. Keywords relating to neurological disorders and violence were searched between 1966 and August 2008. Case–control and cohort studies were selected. Odds ratios of violence risk in particular disorders compared with controls were combined using fixed-effects meta-analysis with the data presented in forest plots. Sensitivity analyses were conducted to identify possible differences in risk estimates across surveys. Information on risk factors for violence was extracted if replicated in more than one study. Nine studies were identified that compared the risk of violence in epilepsy or traumatic brain injury compared with unaffected controls. For the epilepsy studies, the overall pooled odds ratio for violent outcomes was 0.67 [95% confidence interval (CI) 0.46–0.96]. For traumatic brain injury, the odds ratio was 1.66 (95% CI 1.12–2.31). An additional 11 case–control studies investigated factors associated with violence in epilepsy and traumatic brain injury. It was not possible to meta-analyze these data. Comorbid psychopathology was associated with violence. Data on other neurological conditions was limited and unreplicated. In conclusion, although the evidence was limited and methodological quality varied, epilepsy and traumatic brain injury appeared to differ in their risk of violence compared with control populations. Longitudinal studies are required to replicate this review’s provisional findings that epilepsy is inversely associated with violence and that brain injury modestly increases the risk, and further research is needed to provide information on a broader range of risk factors.     

The Sperm Acrosome: Immunological Analysis using Specific Polyclonal and Monoclonal Antibodies Directed Against the Outer Acrosomal Membrane of Boar Spermatozoa

An antiserum to the purified porcine outer acrosomal membrane (OAM) was raised in female Balb/c mice and was characterized by means of an indirect ELISA. The hyperimmune serum reacted selectively with the acrosomal cap of the sperm head and showed an extremely good cross reactivity with bull and human spermatozoa when assayed by indirect immunofluorescence. Immunoelectron microscopy using the protein A-gold method further confirmed the specificity of the anti-OAM-antiserum for the OAM. In an effort to identify the OAM antigens recognized by the hyperimmune serum and to analyse the extent of cross reactivity on a molecular level, the SDS-extractable proteins were separated by SDS-PAGE, transblotted and immunoprinted using an 125J-conjugated anti-mouse-antibody. To facilitate functional and structural analysis of distinct OAM-proteins monoclonal antibodies were generated by hybridization of mouse myeloma cells with the splenocytes of female Balb/c mice immunized with the purified OAM. One fusion resulted in about 100 anti-OAM-antibodies secreting hybridoma cultures, of which about 30% showed cross reaction with human and bull spermatozoa. Four stable cell lines were selected for this study secreting antibodies directed against the outer acrosomal membrane of boar spermatozoa. Whereas the polyclonal immune mouse serum stained the entire acrosomal cap, the four hybridoma antibodies generated a patch-work-like immunofluorescence pattern over the acrosome. HPLC-ELISA of the solubilized OAM revealed first information on the nature of the corresponding membrane antigen.     

Local anesthetics in the aqueous humor in local anesthesia of the eye

Local anesthetics injected retrobulbarly are detectable in the aqueous humor. From 40 patients who received a total dose of 140 mg lidocaine, 15 mg bupivacaine, and 30 mg etidocaine, samples of aqueous humor were taken between 30 and 90 minutes after administration (average 57 minutes). The mean lidocaine concentration was 1.02 micrograms/ml, that of bupivacaine 0.075 micrograms/ml. Etidocaine, used only for facial nerve block in front of the ear, could not be detected in the aqueous humor. All three substances were found in the central venous blood. It therefore appears unlikely that any of them are transported via the blood-aqueous barrier, whether actively or passively. Local anesthetics can inhibit corneal cell proliferation and result in lens opacification when administered into the conjunctival sac. It may be that local anesthetics detected in the aqueous humor have similar effects resulting from contact with the cornea and lens.     

On the effects of Fusarium toxin contaminated wheat and wheat chaff on nutrient utilisation and turnover of deoxynivalenol and zearalenone in vitro (Rusitec).

The objective of the present study was to investigate the effects of Fusarium toxin contaminated wheat and wheat chaff (mycotoxin diet) on nutrient degradability and the metabolism of the mycotoxins deoxynivalenol (DON) and zearalenone (ZON) using the rumen simulations technique (Rusitec). A 6 day application period with control wheat and wheat chaff (control diet) was followed by an 8 day sampling phase. During this time three fermenters received the mycotoxin diet (64.9 mg DON/kg dry matter (DM) and 500 microg ZON/kg DM) and the remaining fermenters served as the controls (1.0mg DON/kg DM and 6 microg ZON/kg DM). Feed residues of the bags and samples of the effluent liquids were pooled per fermenter during the last 8 days of the experiment. Additionally, effluents of the mycotoxin fermenters were taken 6, 12 and 24h after the morning feeding on the first day of the sampling phase. The degradation of organic matter (OM; P<0.05), neutral detergent fibre (NDF; P<0.01) and protein (P<0.001) were increased by administration the Fusarium contaminated diet which was accompanied by an increased ammonia concentration (P<0.01) and increased butyrate (P<0.01), isobutyrate (P<0.01) and isovalerate (P<0.05) values of the mycotoxin effluents in relation to the controls. High proportions of ingested DON of 90% (85-93%) and ingested ZON of 93% (80-104%) were recovered at the pooled feed residues and effluents in form of DON and de-epoxy DON, and ZON and alpha-ZOL after administering the Fusarium toxin contaminated feed. While adsorption of DON as DON and de-epoxy DON in the feed particles was only minor (5%), a higher amount of 38% of ingested ZON was recovered as ZON and alpha-ZOL at the feed residues. The total recovery of DON plus de-epoxy DON in effluents as a percentage of DON intake reached 8%, 9% and 22% of ingested DON at 6, 12 and 24h after application of the contaminated diet the first time, whereby the recovery of de-epoxy DON as percentage of DON intake was only 5% at 24h. Concentrations of ZON and metabolites were lower than detection limits in the time dependent effluent samples.