A new model for experimental tendon adhesions in the chicken

A minimally invasive model using a manual abrader to induce adhesions in the chicken's central digit is described. The flexor synovial sheath and the profundus tendon were abraded with access through small flaps at the level of the proximal and distal phalanges of the avian long toes. The birds were divided into two groups according to the severity of the induced trauma. Group I birds received an abrasion injury and were euthanized to allow biomechanical testing 5 weeks postoperatively. Group II birds had a more severe abrasion and were euthanized similarly and tested 5 weeks after surgery. Results were compared with nonsurgical controls. Long toe function was evaluated weekly by measuring (1) the range of active flexion of each interphalangeal joint, resolved to total angular range; (2) the grasping ability on graded-diameter perches; and (3) the flexion deficit of the long toe. Postmortem biomechanical properties of the adhesions were measured. There was a significant difference between the unoperated controls and abraded digits of both groups in all parameters (p < 0.001). There was, in addition, a marked change in most of the measured parameters between groups I and II. In group I digits the functional and biomechanical deficit was less than group II. In summary, this animal model of long-segment abrasive injury to the tendon and sheath is a simple and reproducible method to generate adhesions and can be used for the evaluation of treatment modalities for adhesion prevention.     

MDMA ("ecstasy") exhibits an anxiogenic-like activity in social encounters between male mice.

Recent studies have suggested that 3,4-methylenedioxymethamphetamine (MDMA; "ecstasy"), a synthetic amphetamine derivative, might exhibit an anxiogenic-like activity in rodents. In this work, we examined the effects of MDMA (1, 8 and 15 mg kg(-1), i.p.) on social encounters between male mice using an ethopharmacological approach. Likewise, we compared the behavioural profile of MDMA with that induced by FG 7142 (15 mg kg(-1), i.p.), an anxiogenic benzodiazepine receptor ligand. Individually housed mice were exposed to anosmic standard opponents 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. MDMA (8 and 15 mg kg(-1)) produced a behavioural pattern characterized by a marked decrease of aggression (threat and attack) as well as social investigation, body care and digging behaviours, without affecting immobility. Moreover, avoidance/flee and defence/submission behaviours were significantly increased by the drug. A very similar behavioural profile was observed in FG 7142-treated animals. Overall, these findings might indicate that MDMA has anxiogenic-like properties in male mice.     

Thallium-201SPECT assessment in the detection of recurrences of treated gliomas and ependymomas

Introduction The aim of this study was to establish the value of thalium-²⁰¹ single-photon emission computed tomography (²⁰¹Tl-SPECT) in the detection of recurrences in the follow-up of patients with treated primary neuroepithelial tumours. Material and methods Sixty-three²⁰¹Tl-SPECT were performed in 36 patients with glioma (12 males, mean age of 46±13 years). All patients underwent surgery and adjuvant radiotherapy (and some of them received chemotherapy). All patients were submitted to morphological neuroimaging techniques as well (and²⁰¹ Tl-SPECT). Mean follow-up was 18.3±14.6 months. Gold standard was based on clinical follow-up, therapeutical decisions (at least 4 months after²⁰¹Tl-SPECT) and imaging features. Results Sensitivity and specificity of²⁰¹Tl-SPECT to detect glioma recurrences were 90% and 100% respectively and 93% accuracy. Sensitivity and specificity for high grade tumours, were 100% respectively. Due to 4 false negatives, sensitivity and specificity for low grade gliomas were 78% and 100%. In the positive²⁰¹Tl-SPECT group of patients overall survival was 13.64% at the end of the study. The negative²⁰¹Tl-SPECT group had 84.62% overall survival at the end of the study (p=0.0003). Conclusions ²⁰¹Tl-SPECT is a valuable and noninvasive diagnostic procedure to detect recurrence or progression disease for treated gliomas and ependymomas.²⁰¹Tl-SPECT has a good correlation with short term prognosis with excellent diagnostic accuracy.     

A man with lung cancer and tuberculosis: a false positive by positron emission tomography and its clinical repercussions

Positron emission tomography (PET) has come to play an increasingly important role in the evaluation of lung cancer patients, both for diagnostic staging and post-treatment follow-up. As is true for other techniques, PET gives false positive and negative results. False positives have been described in the presence of certain active infections and inflammatory lesions, such as tuberculous granulomas, coccidioidomycosis, aspergillosis and histoplasmosis. We report the case of a man whose PET gave a false positive and in whom both lung cancer and tuberculosis were present. A radical change in therapeutic approach was required, making the case interesting.     

Differential effect of thalamic and subthalamic lesions on early and late components of the somatic evoked potentials in man.

The effect of thalamic (Vo), subthalamic (Raprl) and combined (Vo-Raprl) unilateral lesions on early and late components of the somatic evoked potentials (SEPs) was investigated in a group of 16 cases operated on for the treatment of contralateral dyskinetic movements. In these cases, SEPs were independently produced by stimulation of the left and right median nerves and recorded at the corresponding somatosensory scalp regions. In addition, EEG frequencies and reaction time (RT) were independently and bilaterally determined. These tests were performed before and after operation and changes in SEP, EEG and RT were quantitatively evaluated in relation to both ipsilateral preoperative and contralateral postoperative controls. 1. All cases with either thalamic or combined lesions involving Vo nucleus showed an ipsilateral reduction in amplitude of late SEP components and EEG frequency and a contralateral increase RT. A peculiar form of "inattention" to the contralateral hand was also found. Quantitative evaluation of the total group showed significant amplitude reduction in late SEP components in relation to both ipsilateral preoperative and contralateral postoperative controls. Changes in EEG and RT were only significant in relation to their preoperative ipsilateral controls. 2. Two cases with subthalamic lesions and quick postoperative recovery showed no apparent change in SEP, EEG and RT. Three cases with similar lesions and slow postoperative recovery showed bilateral decrease in amplitude of late SEP components, EEG frequency and increase in RT. Clinical inattention to contralateral hand was also found in all these cases. Quantitative evaluation of the total group showed no significant changes in these parameters in relation to preoperative controls. 3. None of these lesions produced changes in early SEP components or somatosensory deficits at the contralateral hand.     

Levels of satisfaction with rheumatoid arthritis treatment and associated alignment between physicians and patients across Latin America

Clinical Rheumatology - Discordance (misalignment) regarding treatment satisfaction may exist in real-life clinical practice between patients and their physicians. We aimed to assess physician and...     

Effect of Hadacidin on Growth and Adenylosuccinate Synthetase Activity of Dictyostelium discoideum

The growth of the eucaryotic microorganism Dictyostelium discoideum in liquid culture was completely inhibited by the aspartic acid analog hadacidin (N-formylhydroxyamino-acetic acid). Growth arrest occurred both in chemically defined medium and in complex growth medium containing aspartic acid and AMP precursors such as adenine and adenosine. Although these compounds could not overcome the effect of hadacidin, growth was restored if cells were washed and resuspended in fresh growth medium. Additional experiments showed that D. discoideum contains adenylosuccinate synthetase, the enzyme which catalyzes the synthesis of adenylosuccinate from IMP, aspartic acid, and GTP in the de novo biosynthesis of purines. A partially purified preparation of this enzyme was obtained, and the effect of hadacidin on its activity was studied. We found that maximum inhibition of the D. discoideum activity occurs at a ratio of aspartic acid to hadacidin of 5:1, suggesting that the affinity of the drug for this enzyme is less than for the enzyme from rabbit muscle and plants but greater than for that from Escherichia coli. The effect of the drug can be overcome by a 10-fold excess of aspartic acid, suggesting that the drug acts as a competitive inhibitor. A comparison of the adenylosuccinate synthetase activity levels at various stages of growth showed that its specific activity decreases about 60% as cells enter the stationary growth phase, and decreases about 75% after starvation for 2 h. Further studies showed that in cells treated with hadacidin the rate of uptake of exogenous nutrients is reduced about 75% and that these cells are more resistant to rupture by osmotic shock. While the results of this study are consistent with the proposal that growth arrest is contingent upon inhibition of adenylosuccinate synthetase activity, they also suggest that, as a consequence of this inhibition, some physiological properties of the cell have been altered.