Study of response of Swiss Webster mice to light subunit of mushroom tyrosinase

The light subunit of mushroom, Agaricus bisporus, tyrosinase (LSMT), has been identified as an extrinsic component of the enzyme. Its function is unknown, but it can cross an epithelial cell layer, which suggests that it can be absorbed by the intestine. A similar capability has been demonstrated for the HA-33 component of the progenitor toxin from Clostridium botulinum, which is the closest structural homolog of LSMT. Unlike HA-33, LSMT appears to be non-immunogenic as shown by preliminary tests in Swiss Webster mice. We investigated the immunogenicity and histopathology of LSMT in mice to determine its safety in vivo. LSMT did not evoke generation of antibodies after prolonged periods of intraperitoneal administration. Histopathological observations confirmed the absence of responses in organs after twelve weekly administrations of LSMT. We found that LSMT is not toxic and is less immunogenic than the C. botulinum HA-33 protein, which supports further research and development for pharmaceutical application.     

A Dutch guideline for the treatment of scoliosis in neuromuscular disorders

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.     

Occult HBV infection and suppression of HCV replication in the early phase of combination therapy for chronic hepatitis C

BACKGROUND: Occult HBV infection in subjects with chronic hepatitis C is related to more severe disease outcome. It has been suggested that it might reduce sensitivity to antiviral treatment. AIMS: To assess in HBsAg negative subjects with chronic hepatitis C any effect of the presence of HBV genomes in the liver on the early kinetics of HCV-RNA under PEG-IFN plus ribavirin. PATIENTS AND METHODS: Twenty-two anti-HCV and HCV-RNA positive subjects, with biopsy-proven chronic hepatitis C (M/F 15/7; 50 +/- 8.6 years, 16 genotype 1b) were given PEG-IFN alpha 2b 1.0 microg qw plus ribavirin (800 to 1,200 mg daily according to body weight) for an intended 52 week period. Early virological response was assessed over the first 4 weeks of therapy by quantifying HCV-RNA. Occult HBV infection was assessed by testing for HBV-DNA in the liver before therapy. RESULTS: HBV genomes were found in the liver of 7 of 22 (31.4%) patients, unrelated to anti-HBc status. Kinetics of HCV-RNA during the first 4 weeks of antiviral treatment was unaffected by occult HBV infection, both in terms of absolute reduction of viral load and of number of cases with a reduction of > or = 2 log10 on treatment. CONCLUSIONS: Occult HBV infection does not affect the early phase of response to combination therapy. Further follow-up of patients into the maintenance phase of antiviral treatment and after stopping it will clarify if and when occult HBV has a role in reducing sustained virological response.     

A three-dimensional mechanical analysis of a stentless fibre-reinforced aortic valve prosthesis

Failure of bioprosthetic and synthetic three-leaflet valves has been shown to occur as a consequence of high tensile and bending stresses, acting on the leaflets during opening and closing. Moreover, in the stented prostheses, whether synthetic or biological, the absence of contraction of the aortic base, due to the rigid stent, causes the leaflets to be subjected to an unphysiological degree of flexure, which is related to calcification. It is shown that the absence of the stent, which gives a flexible aortic base and leaflet attachment, and leaflet fibre-reinforcement result in reduced stresses in the weaker parts of the leaflets in their closed configuration. It is postulated that this leads to a decrease of tears and perforations, which may result in a improved long-term behaviour. The effect of a flexible leaflet attachment and aortic base of a synthetic valve is investigated with a finite element model. Different fibre-reinforced structures are analysed with respect to the stresses that are likely to contribute to the failure of fibre-reinforced prostheses and compared with the results obtained for a stented prosthesis. Results show that for the stentless models a reduction of stresses up to 75% is obtained with respect to stented models with the same type of reinforcement.     

The mitogenome of Onchocerca volvulus from the Brazilian Amazonia focus

We report here the first complete mitochondria genome of Onchocerca volvulus from a focus outside of Africa. An O. volvulus mitogenome from the Brazilian Amazonia focus was obtained using a combination of high-throughput and Sanger sequencing technologies. Comparisons made between this mitochondrial genome and publicly available mitochondrial sequences identified 46 variant nucleotide positions and suggested that our Brazilian mitogenome is more closely related to Cameroon-origin mitochondria than West African-origin mitochondria. As well as providing insights into the origins of Latin American onchocerciasis, the Brazilian Amazonia focus mitogenome may also have value as an epidemiological resource.     

Phytochemical Profile and Antioxidant Activity of the Aerial Part Extracts from Matthiola incana subsp. rupestris and subsp. pulchella (Brassicaceae) Endemic to Sicily

As part of a project aimed at investigating the Matthiola taxa endemic to Sicily (Italy), this study focused on Matthiola incana, an edible species used in the traditional medicine of various countries. Herein, the characterization of phenolic and volatile compounds, the antioxidant capacity in vitro (1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power and Fe²⁺ chelating activity assays) and the toxicity test (Artemia salina lethality bioassay) of the hydroalcoholic extracts from the aerial parts of M. incana subsp. rupestris from Mt. Pellegrino (Palermo) and Mt. Erice (Trapani), and of M. incana subsp. pulchella are reported. The results are compared with those previously shown for M. incana subsp. incana, to achieve a comprehensive overview of the three subspecies. The HPLC-PDA/ESI-MS and SPME-GC/MS analyses led to the identification of 13 phenolics and 54 volatile compounds. Differences in the qualitative-quantitative profile of these phytochemicals have been highlighted between the M. incana subspecies. The antioxidant tests showed different activity for the extracts, which were found to possess better chelating properties. At last, none of the tested extracts displayed toxicity against brine shrimp larvae. These findings enrich the knowledge on the Matthiola taxa growing wild in Sicily, both from the strictly systematic point of view and for the possible applications as sources bioactive compounds that can be used in the nutraceutical field.     

Identification of differentially expressed genes in response to mercury I and II stress in Trichoderma harzianum

Filamentous fungi are very promising organisms in both the control and the reduction of the amount of heavy metal released by human and industrial activities. In particular, Trichoderma harzianum demonstrated to be tolerant towards different heavy metals, such as mercury and cadmium, even though the mechanism underlying this tolerance is not fully understood. By using a particular strategy of the suppression subtractive hybridization technique, we were able to identify in the strain IMI 393899 of T. harzianum eight different genes up-regulated in the presence of mercury II with respect to cadmium. Among the genes identified, a possible role in the tolerance mechanism could be envisaged for hydrophobin, due to its ability to dissolve hydrophobic molecules into aqueous media. We also show that IMI 393899 grows at the same rate of control culture in the presence of mercury I and that all eight genes isolated were also up-regulated in this condition.     

Endothelial activation and injury by cigarette smoke exposure

Endothelial activation/injury following exposure to cigarette smoke may explain incidence of atherosclerosis and cardiovascular disease in smokers. We investigated cigarette smoke extract (CSE) effects relative to activation, injury, and survival of human umbilical vein endothelial cells (HUVEC) and compared circulating levels of specific endothelial activation markers between smokers and healthy non-smokers before and after smoking cessation. Viability and toxicity of HUVEC were tested by MTT and LDH assay. Release (by endothelial cells) and circulating levels (in smokers) of von Willebrand Factor (vWF), thrombomodulin (TM), was evaluated by ELISA. Incubation with increasing concentrations of CSE reduced the percentage of viable cells, being 33.9%, 23.9% after CSE 4%, 6% respectively. Dose- and time-dependent release of LDH was observed after incubation with CSE. vWF, TM release were assayed after CSE 2% HUVEC stimulation. Significant 42%, 61%, 76% increase in vWF concentration was detected respectively at 30', 60', 120'. Reduction in circulating levels of vWF, from a median value of 144.0% to 123.7%, was observed in the quitters group after smoking cessation. Exposure to cigarette smoke is cytotoxic and induces activation/injury of endothelium in vitro and in vivo. These findings may provide pathogenetic basis by which smoking can predispose to development of atherothrombosis and cardiovascular disease.