In vitro release and In vivo biocompatibility studies of biomimetic multilayered alginate-chitosan/β-TCP scaffold for osteochondral tissue

Biomimetic three-layered monolithic scaffold (TLS) intended for the treatment of osteocondral defects was prepared by using alginate, chitosan and β-tricalcium phosphate (β-TCP) to study drug release behavior of the alternative drug delivery system and to investigate the therapeutic efficacy of the scaffold. Dexamethasone sodium phosphate (Dex) as a model drug was incorporated into the scaffold by solvent sorption method and in vitro release studies were conducted. In addition, the scaffold was implanted into the defects formed in the trochlea of Sprague–Dawley rats to assess the healing potential of the TLS on the osteochondral defect against reference Maioregen® comparatively. The release studies showed that after an initial burst at 3rd h, dexamethasone is released slowly during a 72-h period. In vivo studies indicated that the TLS has good tissue biocompatibility and biodegradation rate and showed better results during osteochondral healing process compared to the reference. All results demonstrated that the alginate-chitosan/β-TCP scaffold could be evaluated as a good candidate for osteochondral tissue applications.     

ERN varies with degree of psychopathy in an emotion discrimination task

It is hypothesized that anterior cingulate cortex (ACC) function may be disrupted in psychopathy. Since ACC is considered the generator of the error-related negativity (ERN), we expected the ERN to be sensitive to the degree of psychopathy among violent offenders. EEG was collected while offenders and controls responded to a standard letter flanker task and to a face flanker task that required discrimination between angry and fearful expressions. Offenders were as accurate as controls on the letter flanker task but made more errors in emotion discrimination on the face flanker task. ERNs elicited by letter flanker errors did not differ across groups but were markedly reduced in the offenders in the face flanker condition. These effects were related to the degree of psychopathy within the offender group. Source modelling of the ERN also indicated an atypical response for psychopaths when error monitoring required the discrimination of affectively based information.     

The pulmonary involvement in rheumatic diseases: pulmonary effects of ankylosing spondylitis and its impact on functionality and quality of life

Rheumatic diseases are chronic inflammatory diseases which cause mild to severe functional loss and disability due to articular and extra-articular manifestations. One common form -ankylosing spondylitis (AS)- affects mainly the axial skeleton and sacroiliac joints, and certain extra-articular organs. The pulmonary involvement is a known manifestation of AS and emerges either in the form of interstitial lung disease or in the form of restricted pulmonary functions. The aim of this study is to determine the pulmonary functions in AS patients and to assess its relationship with quality of life, functionality and disease activity. Thirty-six AS patients and 34 healthy volunteers were recruited for the study. A detailed examination, pulmonary function tests, smoking inquiry and quality of life questionnaire were performed on all participants. Also patients were requested to complete functionality and disease activity indexes. The outcomes showed that 15 (41.7%) AS patients had pulmonary involvement: twelve patients with restrictive patterns, one with obstructive pattern, and two with both restrictive and obstructive patterns. Decreased forced expiratory volume in one second was associated with deteriorated functionality (p < 0.05). Decreased chest expansion was also accompanied with decreased forced vital capacity (p < 0.05). There was no statistically significant difference between the smoking and non-smoking patients in regard to disease activity, functionality and pulmonary function test variables (p > 0.05). In conclusion, the pulmonary involvement is common in AS and might have disturbed functionality and the quality of life in AS patients.     

Metformin decreases testicular damages following ischaemia/reperfusion injury in rats

The effects of metformin on a testicular torsion injury in adolescent rat testis after I/R were evaluated in the present study. Forty adolescent rats were divided into five groups with eight rats per group: a control group; a sham-operated group; an ischaemia group, where torsion was applied for 4 hr and testis was examined immediately after detorsion; an I/R group, where torsion was applied for 4 hr and the testis was examined 4 hr after detorsion; and an I/R + M group, where the metformin (300 mg/kg) administration was added to the identical procedures used for the I/R group. Spermatogenesis, basal membrane integrity and cleaved caspase-3 expression were assessed. The I/R + M group had a significantly higher Johnsen score than the I/R group (7.9 ± 0.1 vs. 7.5 ± 0.2; p < .001; F-value = 14.2). Failure of basal membrane integrity was highest in the ischaemia group (45 ± 5) compared to the other groups (control group, 20 ± 5; sham-operated group, 16.6 ± 2.8), but not different between the I/R + M (31.6 ± 12.5) and the I/R groups (25 ± 3.5). Cleaved caspase-3 expression was highest in the ischaemia group (73.5 ± 0.7), and significantly lower in the I/R + M group (33.4 ± 0.9) than the I/R group (58.5 ± 0.2; p < .05; F-value = 7.6). Metformin decreases testicular damage by exerting protection against the harmful effects of I/R on spermatogenesis and alleviating apoptosis in adolescent rat testis.     

Miliary tuberculosis associated with multiple intracranial tuberculomas

In this study we have reported a 12-year old girl patient who visited out-patient clinic with the history of headache and convulsion. The patient was diagnosed as miliary tuberculosis and multiple brain tuberculomas. Miliary infiltration was observed in chest x-ray and high-resolution thorax computed tomography (CT), and multiple tuberculomas surrounded with wide edema was observed in Magnetic Resonance Imaging (MRI). Acid-fast bacilli were detected in inducted sputum and gastric fluid. Focal epileptiform activity was seen in electroencephalography (EEG). The patient was administered antitubercular, anti-edema and antiepileptic therapy. The patient had not experienced convulsion for the second time and EEG had been normal; therefore her treatment was completed within 12 months. Chest x-ray and high-resolution thorax CT findings turned to normal and brain MRI findings improved significantly. As a conclusion, tuberculosis disease has very different clinical pattern depending on the organs it involves. The significance of our case is due to the presence of both the miliary tuberculosis and intracranial tuberculomas. The patient was admitted to the hospital due to central nervous system symtoms rather than pulmonary symptoms.     

Hydrogenated derivatives of hexacoordinated metallic Cu2Si monolayer

Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu₂Si monolayer. Pristine Cu₂Si, a metallic monolayer, has a planar hexacoordinate structure. Calculations revealed that the most favorable position of a single H atom on the Cu₂Si monolayer is at the top of a Si site. Derivatives of Cu₂Si monolayer with various H concentrations were investigated, and by performing phonon calculations, it was found that there are three stable hydrogenated structures. Specific heat of these monolayers was found to increase with the hydrogen concentration at temperatures higher than 100 K. Electronically, the hydrogenated derivatives of Cu₂Si monolayer preserve the metallic character.

Herein, we carried out first-principles calculations based on density functional theory to investigate the effects of surface functionalization with hydrogen atoms on structural, dynamical and electronic properties of Cu₂Si monolayer.     

Tuberculin skin test screening in a military school in Istanbul city center

To investigate the reason of high incidence of annual patients with tuberculosis (TB) in a military school previously known by screening tuberculin skin test (TST) and finding out the proportion of annual infection risk (PAIR), the prevalance of TB infection and the distribution for each grades. Our study is a cross-sectional epidemiologic study made about TB infection. TST were screened for all students in the school. 5 TU PPD was injected to every student and after 72 hours, the results were evaluated by measuring the diameter of enduration. Test was repeated after 10 days for negative reactions. Age, sex, the number of BCG wound, smoking and dwelling for last 5 years were asked from the students and their answers were recorded. More than 10 mm enduration for cases who had no BCG and 15 mm enduration for cases who had BCG were accepted positive. Chest roentgenogram was taken for each student enrolled into the study. Infection prevalance and PAIR were calculated after tests and measurements. The total number of students was 948. Of 917 (96.7%) were male and 31 (3.3%) were female. The mean age was 19.72 +/- 1.25. The mean of TST was 12.79 +/- 5.96 mm for all students. According to the number of BCG scar, the numbers of students, percentage and the mean of TST were like that 70 (7.3%) cases no BCG scar 8.41 +/- 7.87 mm, 393 (41.4%) students one BCG scar, 11.94 +/- 6.26 mm, 343 (36.1%) cases two BCG scars, 13.74 +/- 5.12 mm, 142 (14.9%) students three or more then three scars, 14.97 +/- 4.11 mm. In the students who had no BCG, TST positivity was 50%. TB infection prevalance of entire school and PAIR were 46% and 3.44% (respectively). In this study, we found that increased number of BCG wound associated with the increased diameter of TST enduration. The proportion of unvaccinated students was similar to the same age population in our country but it showed differences in the distribution of regions. The students who started first grade had serious TB infection risk in their first school year. We think that PAIR values derived from TST conversions done in high risky community by screening annual TST could show all aspects of TB infection risk in those community.     

Treatment in patients with low traumatic pneumothorax ratio

Thoracostomy tube placement (TT) is currently one of the most important treatment modalities used in traumatic pneumothorax patients. In patients with low pneumothorax ratio (percentage), both follow-up without surgery and employing intervention when indicated may be appropriate choice. We presented the outcome of patients with low traumatic pneumothorax ratio treated by follow up without surgical intervention in our clinic. During the period from January 2000 until January 2002, 108 patients who were treated and followed with low percentage traumatic pneumothorax in Ankara Numune Hospital Thoracic Surgery Clinic were allocated into three groups due to blunt trauma of the thorax, penetrating-cutting instrument injury and gunshot injury. All patients were admitted to the clinic with the purpose of observation without surgical intervention and chest roentgenograms were taken at the sixth and twelfth hours and daily thereafter. TT was performed for 46 (43%) patients whose pneumothorax ratio increased during the observation period. TT was more frequent in patients with 20% percentage pneumothorax (69%) as well as with two or more fractured ribs (69%). Follow-up without surgical intervention may one of the appropriate modes of treatment in patients who have minimal traumatic pneumothorax.     

Protruded and nonprotruded subungual exostosis: Differences in surgical approach

Background:

In subungual exostosis surgery, repair of the damaged nail bed and surgical excision of the mass without damaging the nail bed is important. The ideal method of surgery is still unclear. This study is done to qualify the effects of different surgical methods on outcome measures in different types of subungual exostosis.

Materials and Methods:

Fifteen patients, operated with a diagnosis of subungual exostosis between January 2008 and June 2012, were evaluated. Protruded masses were excised with a dorsal surgical approach after the removal of the nail bed and nonprotruded masses were excised through a“fish-mouth” type of incision.

Results:

The mean age of the patients in protruded subungual exostosis group was 17.3 years (range 13-22 years) and this group consisting of seven female and two male patients. The patients were followed up for a mean of 14.1 ± 4.8 months. The mean age of the patients in the nonprotruded subungual exostosis group was 14.6 years (range 13-16 years) and consisting of six female patients. The patients were followed up for a mean of 11.6 ± 2.9 months. The results were positively affected by changing the surgical approach depending on whether or not the exostosis is protruded from the nail bed. All patients had healthy toe nails in the postoperative period without any signs of recurrence.

Conclusions:

In patients with a protruded subungual exostosis, the mass should be removed by a dorsal approach with the removal of the nail and injury to the nail bed should be repaired. In patients with a nonprotruded subungual exostosis, the mass should be excised through a “fish-mouth” type incision at the toe tip without an iatrogenic damage.