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Atrophy of the dentate nucleus is one of the major neuropathological changes in Friedreich ataxia (FRDA). Neuroimaging studies demonstrated white matter (WM) degeneration in FRDA. In this study, we used advanced tractography techniques to quantitatively measure WM changes in the dentato-thalamic and dentato-rubral tracts, and correlated these changes with cognitive profiles of FRDA. We also analysed diffusivity changes of the thalamo-cortical tract to assess whether neurological degeneration of WM extends beyond the primary site of involvement in FRDA. Twelve genetically proven individuals with FRDA and 14 controls were recruited. Sixty directions diffusion tensor images were acquired. The WM bundles from the dentate nucleus were estimated using a constrained spherical deconvolution method and the diffusivity characteristics measured. The Simon task was used to assess cognitive profile of FRDA. The dentato-rubral, dentato-thalamic and thalamo-cortical tracts manifested significantly lower fractional anisotropy, higher mean diffusivity and increased radial diffusivity in FRDA compared with controls. There was no difference in axial diffusivity between the two groups. The mean and radial diffusivity of the dentato-rubral tract was positively correlated with choice reaction time, congruent reaction time, incongruent reaction time and Simon effect reaction time and negatively with the larger GAA repeat. Significant changes in diffusivity characteristics were observed in the dentato-thalamic and thalamo-cortical tracts, suggesting extensive WM degeneration and affected WM structures in FRDA. Correlation of WM changes in the dentato-rubral tract with the cognitive assessment suggested that this tract is an important contributor to cognitive disturbances in FRDA.

Unlabelled: Ferula ovina (Boiss.) Boiss. is a traditional Iranian flavoring agent used as an ingredient of spices and condiments., Methods and Results: GC-MS analyses of F. ovina aerial parts' essential oil revealed the presence of a number of rare aromatic esters of monoterpenic alcohols. The structures of these esters were corroborated by synthesis, and one of them, bornyl 4-methoxybenzoate, turned out to be a new natural compound. The antinociceptive activities of the oil and the new ester were assessed in mice using several different laboratory models. The oil exerted strong peripheral and moderate central analgesic activities. Surprisingly, mice treated with bornyl 4-methoxybenzoate had an increased sensitivity to the noxious stimulus compared to that of the control group. A dynamic hot plate test was used to demonstrate that bornyl 4-methoxybenzoate induces hyperalgesia and not allodynia., Conclusion: Essential oil constituents impart this spice with both antinociceptive and hyperalgesic potentially flavor-related properties.

Objective: To evaluate whether biomarkers of inflammation and periodontal remodeling are differentially expressed in the gingival crevicular fluid (GCF) of patients wearing different types of orthodontic retainers., Materials and Methods: Thirty-one adult subjects (17 men and 14 women with an age range of 20 to 35 years) were allocated to three different groups. Group 1 consisted of 10 patients wearing fixed retainers, group 2 included 11 patients using lower removable retainers, and group 3 comprised 10 patients without retainers (control). Periodontal health assessment and GCF collection were carried out at two sites per subject: the lingual side of a central lower incisor and the lingual side of a lower second premolar. Aliquots from diluted GCF were screened for the presence of biomarkers using a microarray technique., Results: Group 1 patients exhibited a higher percentage of sites with visible plaque in the incisor region than the other groups (P = .03); no differences were noted in gingival bleeding and probing depths. The median concentrations (pg/mL) of interferon-gamma and interleukin-10 were significantly higher in the premolar sites of patients in group 2 (P = .01 and P = .04, respectively), whereas the concentration of matrix metalloproteinase-9 was significantly higher at the incisors of patients wearing fixed retainers (P = .02). A significant difference between the two sites was seen only in group 2., Conclusions: The presence of different orthodontic retainers may promote specific alterations in the GCF composition. With retention periods potentially becoming longer, this finding may be of clinical significance.

Friedreich's ataxia (FRDA) is the most common early onset inherited ataxia with clinical manifestations, including gradual progression of unremitting cerebellar-sensory ataxia, peripheral sensory loss, loss of lower limb tendon reflexes and hypertrophic cardiomyopathy. Although atrophy of the superior cerebellar peduncle (SCP) has been reported in several magnetic resonance imaging (MRI) studies of FRDA, the relationship of SCP changes to genetic and clinical features of FRDA has not been investigated. We acquired T1-weighted MRI scans in 12 right-handed individuals with FRDA, homozygous for a GAA expansion in intron 1 of FXN, as well as 13 healthy age-matched controls. The corrected cross-sectional areas of the right (left) SCP in the individuals with FRDA (R, 20 ± 7.9 mm(2); L, 25 ± 5.6 mm(2)) were significantly smaller than for controls (R, 68 ± 16 mm(2); L, 78 ± 17 mm(2)) (p < 0.001). The SCP volumes of individuals with FRDA were negatively correlated with Friedreich's ataxia rating scale score (r = -0.553) and disease duration (r = -0.541), and positively correlated with the age of onset (r = 0.548) (p < 0.05). These findings suggest that structural MR imaging of the SCP can provide a surrogate marker of disease severity in FRDA and support the potential role of structural MRI as a biomarker in the evaluation of neurodegenerative diseases and therapies.

Healthcare workers and medical students are at risk of exposure to blood-borne viruses such as HBV, HCV HIV, etc. Here we report the results of a survey of the frequency and causes of cutaneous blood exposure accidents (CBEA) among medical students. Anonymous questionnaires were randomly distributed to 200 interns in their second year of internship in hospitals affiliated to Tehran University of Medical Sciences. A definite exposure was defined as injury by a sharp object causing obvious bleeding, whereas a possible exposure was defined as subtle or superficial injury due to contact with a contaminated instrument or needle but without bleeding, or contamination of an existing wound with blood or other body fluids. One hundred eighty-four subjects (92% of the original sample) responded to the questionnaire. We recorded 121 definite exposures and 259 possible exposures over a mean time interval of 14 months. Needles were the most common objects (41% of exposure episodes) causing CBEAs, while phlebotomy and suturing were the hospital procedures that accounted for the highest percentage of exposure episodes (30 and 28 percent, respectively). Only a minority of students regularly observed basic safety measures (wearing gloves, not recapping used needles and proper disposal of sharp objects). Considering the high incidence of blood exposure in medical interns at Tehran University of Medical Sciences and the ensuing risk of blood-borne infections, the subjects are likely to develop such infections during their internship period.

Tracheobronchopathia osteochondroplastica is a rare benign disorder affecting the trachea and the bronchi. We report a case presenting as difficulty during tracheal intubation. Chest roentgenogram revealed nothing before surgery. Findings on computed tomographic imaging scans show calcified nodular densities protruding into the tracheal lumen, with an abnormally irregular tracheal morphology and decreased lateral diameter. The fiber optic bronchoscopy, which was unable to pass more than 4 to 5 cm, showed enormous prominent protrusion with significant narrowing of the tracheal lumen. The diagnosis was confirmed by virtual bronchoscopy, which showed a tracheal narrowing with a beaded appearance and an irregular border that extended into the trachea and main bronchi.