Correlation between gamma glutamyltransferase fractions and bone quality.

Gamma-glutamyltransferase (GGT) has been recently identified as a bone-resorbing factor. The aim of this study was to investigate the association between plasma GGT fractions levels and bone quality. Plasma GGT fractions were analysed by gel-filtration chromatography. Bone quality was established quantitatively by two micro-CT derived microarchitectural parameters: the BV/TV (mineralised bone volume/total volume), and the SMI (structure model index) that describes the rod-like (low resistant) or plate-like (high-resistant) shape of bone trabeculae. We enrolled 93 patients hospitalised for elective total hip replacement (group Arthrosis, n=46) or for proximal femoral fracture (group Fracture, n=47). Patients within the first quartile of BV/TV (Q1, osteoporotic patients, n=6) showed higher levels of b-GGT fraction [median (min-max): 3.37 (1.42­6.81)] compared to patients with normal bone density (fourth quartile Q4, n=10; 1.40 (0.83­4.36); p=0.0393]. Also, according to SMI, b-GGT value was higher in the subgroup with bone fragility [Q1, n=8: 1.36 (0.43­4.36); Q4, n=8: 5.10 (1.4 ­7.60); p=0.0117]. In conclusion, patients characterised by fragile bone structure showed specifically higher levels of plasma b-GGT activity thus suggesting fractional GGT analysis as a possible biomarker in the diagnosis of osteoporosis.

Neural correlates of decision making on whole body yaw rotation: An fNIRS study.

Prominent accounts of decision making state that decisions are made on the basis of an accumulation of sensory evidence, orchestrated by networks of prefrontal and parietal neural populations. Here we assess whether these findings generalize to decisions on self-motion. Participants were presented with whole body yaw rotations of different durations in a 2-Interval-Forced-Choice paradigm, and tasked to discriminate motions on the basis of their amplitude. The cortical hemodynamic response was recorded using functional near-infrared spectroscopy (fNIRS) while participants were performing the task. The imaging data was used to predict the specific response on individual experimental trials, and to predict whether the comparison stimulus would be judged larger than the reference. Classifier performance on the former variable was negligible. However, considerable performance was achieved for the latter variable, specifically using parietal imaging data. The findings provide support for the notion that activity in the parietal cortex reflects modality independent decision variables that represent the strength of the neural evidence in favor of a decision. The results are encouraging for the use of fNIRS as a method to perform neuroimaging in moving individuals.

The fifty most cited Italian articles in the orthopaedic literature.

PURPOSES: It is widely known that in Orthopaedics, as in each specialty, the academic influence of an article is also determined by the number of times the article is cited. The aim of this study was to identify the 50 most frequently cited Italian orthopaedics journal articles and to analyse the characteristics that might have made them more citable. METHODS: Science Citation Index Expanded was searched for the 50 most frequently cited Italian orthopaedics journal articles between 1988 and 2013 in the subject category "Orthopaedics". RESULTS: The 50 most frequently cited articles were all published in English and were published in 12 of the 67 journals in the subject category "Orthopaedics" in the Institute for Scientific Information Web Science (Thomson Reuters, New York, New York, USA). One half of the articles were published before 2000 and the other half later. The number of citations ranged from 423 of the first article (mean citation/years 21.15) to 83 of the fiftieth (mean citation/years 16.60). The articles were all categorized under orthopaedic field, but each of them spanned from orthopaedics to a specific sub-specialty. The majority was clinical articles (n = 39), and the most common fields were sport orthopaedic surgery (including arthroscopy and cartilage) (n = 19) and biomechanics (n = 12). CONCLUSIONS: This list of 50 most frequently cited Italian articles is, to our knowledge, significantly important for the general orthopaedic scientific community, particularly for the Italian orthopaedic community. Researchers and doctors may use this work to make their future publications more influential and citable.

Clinical features of X linked juvenile retinoschisis associated with new mutations in the XLRS1 gene in Italian families.

AIMS: To describe the clinical phenotype of X linked juvenile retinoschisis in eight Italian families with six different mutations in the XLRS1 gene. METHODS: Complete ophthalmic examinations, electroretinography and A and B-scan standardised echography were performed in 18 affected males. The coding sequences of the XLRS1 gene were amplified by polymerase chain reaction and directly sequenced on an automated sequencer. RESULTS: Six different XLRS1 mutations were identified; two of these mutations Ile81Asn and the Trp122Cys, have not been previously described. The affected males showed an electronegative response to the standard white scotopic stimulus and a prolonged implicit time of the 30 Hz flicker. In the families with Trp112Cys and Trp122Cys mutations we observed a more severe retinoschisis (RS) clinical picture compared with the other genotypes. CONCLUSION: The severe RS phenotypes associated with Trp112Cys and to Trp122Cys mutations suggest that these mutations determine a notable alteration in the function of the retinoschisin protein.

The decrease of free epsilon-amino groups in senile and diabetic cataracts.

Free epsilon-amino groups in soluble and insoluble proteins were measured in clear human lenses and in diabetic and nondiabetic senile cataractous lenses. The free epsilon-amino group content of soluble and insoluble proteins was significantly lower in diabetic cataracts than in clear lenses and nondiabetic senile cataracts. Our results seem to demonstrate that nonenzymatic glycosylation of lens proteins could play a role in the pathogenesis of diabetic cataract.

Lipid peroxidation and human cataractogenesis in diabetes and severe myopia.

To investigate the role of lipid peroxidation in human cataract, malondialdehyde, a breakdown product of lipid peroxidation, was measured in clear and cataractous lenses from normal subjects, and in cataractous lenses from diabetics and from subjects with severe myopia. The cataractous lenses contained more malondialdehyde than did clear lenses and the level was higher in diabetes and severe myopia than in the idiopathic forms. This indicates that lipid peroxidation may be involved in the development of senile cataract and, as a direct consequence of retinal damage, also in the pathogenesis of cataract in diabetes and in severe myopia.

Systemic human diseases as oxidative risk factors in cataractogenesis. I. Diabetes.

In this study we have investigated the oxidative metabolism of red blood cells (RBC), plasma, serum, aqueous humor, and lens of healthy subjects and of age-matched cataractous patients with and without diabetes. Reduced and oxidized glutathione (GSH GSSG) levels in RBC were similar among the three groups. Plasma levels of GSSG were higher in diabetics than in cataractous and control subjects. No differences in plasma content of GSH were noted among the three groups. The activity of the enzyme glucose-6-phosphate dehydrogenase was significantly diminished in diabetic patients. Controls and cataractous patients showed similar levels of malondialdehyde (MDA). Although not significant the MDA content in RBC from diabetics was elevated. No differences in plasma levels of vitamin E were noted among the three groups. The biological liquid oxidant activity of serum in diabetic patients was significantly higher than in controls and cataractous patients. GSH levels in aqueous humor were similar in diabetic and nondiabetic cataractous patients. The content of GSSG in aqueous humor was highest in diabetic patients. Control clear lenses showed low levels of MDA. The MDA levels in cataractous lenses from nondiabetic patients were significantly higher than those of controls. In diabetic patients the content of MDA in the lens was approximately twice as high as the cataractous values. Our results seem to demonstrate that oxidative damage could play a role in the pathogenesis of cataract in diabetes.