Effect of Tropicamide on Laser Flare Meter Measurements in Patients with Pseudoexfoliation

ABSTRACT

Purpose

To investigate the effect of 1% tropicamide on anterior chamber aqueous flare (ACAF) measurements acquired with laser flare meter in patients with pseudoexfoliation.     

Evaluation of Tc-99m(V) DMSA for imaging inflammatory lesions: An experimental study

The present study evaluated^99mTc(V) DMSA as an agent for the visualization of inflammatory lesions in comparison to^99mTc(HI) DMSA and^99mTc-HIG. All three radiopharmaceuticals were prepared with commercial kits.^99mTc(V) DMSA was prepared at neutral pH by the addition of first bicarbonate and then pertechnetate to the kit contents. The labeling efficiency was 99% as determined by ITLC. Abscesses were induced by i.m. injection of 50 μl turpentine into the right thighs of 36 Swiss albino mice. Six days later 3.7 MBq of each radiopharmaceutical was i.v. administered to 12 mice. The mice were sacrificed at 1,3,6 and 24 h later. Scintigrams were obtained with a gamma camera. The abscesses were better visualized on scintigrams with^99mTc(V) DMSA compared to^99mTc(III) DMSA, starting at 1 h. The animals were dissected and the organs were removed, weighed and the radioactivity determined with a gamma counter. The abscess to other tissue ratios were higher with^99mTc(V) DMSA than the other radiopharmaceuticals. The max. abscess/muscle ratios were 9.46 ± 3.20 (24 h), 4.19 ± 1.39 (6 h) and 5.98 ± 1.17 (24 h) and max. abscess/blood ratios were 6.22 ± 1.41, 4.09 ± 0.84 and 0.914 ± 0.351 all at 24 h for^99mTc(V) DMSA,^99mTc(III) DMSA and^99mTc-HIG, respectively. Experimental arthritis was produced in 6 New Zealand white rabbits by intra-articular injection of ovalbumin. Four days later 37 MBq of^99mTc(V) DMSA and^99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h clearly demonstrated arthritic joints. ROFs over arthritic joints were compared to contralateral normal joints (A/C). The max. A/C ratios were 2.10 ± 0.31 (3 h) and 2.92 ± 0.99 (24 h) for^99mTc(V) DMSA and^99mTc-HIG, respectively. Our results indicated the feasibility of imaging inflammatory lesions with^99mTc(V) DMSA.     

Subtype determination of soma-dendritic α2-autoreceptors in slices of rat locus coeruleus

The aim of the study was to subclassify the soma-dendritic α₂-autoreceptors in the locus coeruleus (LC) of the rat by means of antagonists. To this end, the frequency of spontaneous action potentials was recorded extracellularly from single LC neurones in brain slices. The neurones fired spontaneously at an average rate of 1 Hz. The selective α₂-adrenoceptor agonist 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline (UK 14,304) and noradrenaline decreased the action potential discharge with IC₅₀ values of 5 and 510 nM, respectively. The concentration-inhibition curves of UK 14,304 and noradrenaline were shifted to the right by phentolamine (0.15 μM) and rauwolscine (0.15 μM) but not by prazosin (1 μM). Apparent K _d values of phentolamine were 17 nM (against UK 14,304) and 20 nM (against noradrenaline). Apparent K _d values of rauwolscine were 47 nM (against UK 14,304) and 70 nM (against noradrenaline). (+)-Oxaprotiline (1 μM) suppressed the firing of the neurones within 10 to 33 min. In the continued presence of oxaprotiline, phentolamine and rauwolscine restored firing with EC₅₀ values of 120 and 250 nM, respectively. Prazosin (1 μM) again was ineffective. All three antagonist affinity estimates – against UK 14,304, exogenous noradrenaline and endogenous noradrenaline (that accumulates in the extracellular space in the presence of oxaprotiline) – yield an affinity order phentolamine > rauwolscine >> prazosin, prazosin being ineffective even at a concentration of 1 μM. These findings identify the soma-dendritic α₂-autoreceptors of the LC as the rat variant of the α_2A/D-adrenoceptor, i.e. α_2D. Not only presynaptic but also soma-dendritic α₂-autoreceptors may at least predominantly be α_2A/D throughout the nervous system. Received: 3 March 1997 / Accepted: 21 April 1997     

Recurrent Cervical Abscess Due to Pyriform Sinus Fistula-A Case Report

The pyriform sinus fistula is rare congenital anomaly of either third or fourth branchial pouch, which most frequently presented itself by recurrent episodes of neck abscess for long time. Majority of patients with this anomaly presented with symptoms before 10 years and it is more common than has previously been commonly found on leftside (93%). Clinically high index of suspicion, cannulation of the tract under general anaesthesia, Direct laryngoscopy and fistulogram have freequently been successful in identifying the presence of these embryological remnants. Surgical exploration of sinus tract with its total excision, guided with cannula inside its lumen is the definitive treatment.     

In Hungary,the Old Medical Ethics Meets the New

Medical ethics in Hungary has finally moved beyond arguments over tipping and bribes to discussions of euthanasia, confidentiality, truth-telling and informed consent. Ethics committees have been formed at the local and national level, and medical schools are beginning to take seriously the systematic teaching of medical ethics. In some quarters, however, old attitudes persist. Among older doctors paternalism reigns supreme, and lawmakers continue to ignore international ethical guidelines.