PubMed Health⌕ Search

Biomedical subjects

T Ugur

Publications and source records attributed to T Ugur.

6 recordsLinked to original sources
PubMed2004

Recurrent posterior reversible encephalopathy syndrome (PRES).

Posterior reversible encephalopathy syndrome is a proposed cliniconeuroradiological entity characterized by headache, altered mental status, cortical blindness, seizures, and other focal neurological signs, and a diagnostic magnetic resonance imaging picture. A variety of different etiologies have been reported like hypertension, pre-eclampsia/eclampsia, cyclosporin A or tacrolimus neurotoxicity, uraemia and porphyria. With early diagnosis and prompt treatment, the syndrome is usually fully reversible. We report a case of recurrent PRES of unknown aetiology following intensive care unit treatment and only moderately elevated blood pressure. Clinicians as well as radiologists must be familiar with this clinically frightening, underdiagnosed condition to assure timely diagnosis and treatment to prevent persistent deficits.

Adult↗
PubMed1999

Enlarged gamma band response of neuromagnetic auditory evoked fields in a visually impaired subject.

Under acoustic stimulation a phase-locked response in the gamma band (near 40 Hz) in the latency range between 20 and 130 ms is evoked. We report on a considerably visually impaired woman with Grönblad-Strandberg syndrome which involves degeneration at the level of retina, but has no overt central nervous component to the degeneration. The subject exhibited an extraordinarily high power in the phase-locked gamma band response (GBR) which was found to be more than three, and sometimes more than four, standard deviations above the average of a group of 25 subjects with normal vision. Furthermore, the dipoles of her mismatch reaction and M200 were found to be located posteriorly to the dipoles of the M100. Overall, both enlarged GBR and changed cortical representation could be results of cortical plasticity related to visual impairment.

Acoustic Stimulation↗
PubMed1999

A comparison of different treatment techniques for posterior crossbite in the mixed dentition.

In this retrospective investigation, the changes occurring during the treatment of patients with posterior crossbite in the mixed dentition with the use of expansion plate and quad-helix appliances were evaluated and compared with those resulting from growth and development occurring in a control group of patients of similar age and type of malocclusion. The expansion plate group consisted of 13 patients, the quad-helix group of 14 patients, and the control group consisted of 10 children with transverse posterior crossbites in the mixed dentition. The research material was formed from orthodontic models and lateral and frontal cephalometric radiographs from 37 children. It was observed in this investigation that transverse expansion is achieved by both the expansion plate and quad-helix appliances. However, the average period of treatment was 1.2 years for the expansion plate, and 0.6 years for the quad-helix appliance. Although posterior crossbite was corrected in a fairly short period of time, the quad helix appliance caused considerable buccal tipping of the maxillary first permanent molars.

Case-Control Studies↗
PubMed1996

The mechanisms of taurine mediated protection against cell damage induced by hypoxia and reoxygenation.

Taurine administered during hypoxia markedly reduced the cell damage due to O2 deficiency and reoxygenation. Different mechanisms are responsible for the improved survival of the renal cell cultures. Taurine markedly reduces the osmoregulatory deterioration during hypoxia and reoxygenation. Calcium homeostasis was markedly improved. Ca2+ efflux during hypoxia as well as Ca2+ overload during reoxygenation was significantly reduced by the amino acid. The effect of taurine was partly comparable to the effect induced by Ca2+ channel blockers. One of the effects mainly responsible for cellular protection seems to be the taurine-induced acceleration of cellular growth processes in spite of hypoxia and reoxygenation. The spectrum of cytoprotective effects of taurine predisposes this substance to be a physiological protective agent responsible for cellular homeostasis or enantiostasis.

Aerobiosis↗
PubMed1996

Non-invasive measurement of thyroidal iodine content (TIC) by X-ray fluorescence analysis (XFA).

The determination of thyroidal iodine content by X-ray fluorescence analysis is based on the phenomenon that the gamma radiation of Americium-241 excites stable iodine atoms to emit a characteristic fluorescence radiation which is proportional to the amount of iodine present in the gland. To study this, a stationary system has been developed which consists of a 11.1 GBq Am-241 source and a high-purity Germanium detector with spectrum analysator. Lower limit of detectability of this system corresponds to 0.013 mg per ml of thyroid volume measured sonographically; in-vivo precision given as coefficient of variation of duplicate measurements amounts to 12%. The thyroid is exposed with a radiation dose of 60 microSvs per measurement (approximately 5 % of a Tc-99m scan). Studies carried out in 149 volunteers and 173 patients showed a mean iodine concentration of 0.325 +/- 0.134 mg/ml in healthy persons; decreased iodine concentrations were found in euthyroid goitre patients and hyperthyroid patients with focal functional autonomy or Graves' disease. Iodine concentrations correlated negatively with age and goitre volume. The method is well suited for individual follow-up studies exploring different treatment modalities because of its sensitivity, high reproducibility and low radiation exposure.

Adult↗