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Biomedical subjects

F Grunwald

Publications and source records attributed to F Grunwald.

13 recordsLinked to original sources
PubMed1995

Diminished Tc-99m HMPAO pulmonary uptake in ex-smokers.

Normally, there is no localization of Tc-99m HMPAO in the lungs. Tc-99m uptake in smokers' lungs has been reportedly higher than in nonsmokers. Thus, the lung uptake may be used as a barometer of cigarette smoking. To assess whether there is a decrease in pulmonary uptake of Tc-99m HMPAO after cessation of smoking, the authors investigated the lung uptake of 31 male ex-smokers in comparison to smokers and nonsmokers. Anterior and posterior images were taken 10 minutes after intravenous injection of 20-25 mCi of Tc-99m HMPAO. Regions-of-interest over the liver and lungs in the anterior view were calculated. Duration of abstinence from smoking ranged from 5 months to 50 years. The mean lung/liver uptake in ex-smokers was 0.489 +/- 0.019 (sem). In a previous report, the mean lung/liver ratio for smokers (N = 30) was 0.805 +/- 0.040 (sem) and 0.408 +/- 0.019 (sem) for nonsmokers (N = 25). Compared with smokers, the lung/liver uptake ratio of ex-smokers was significantly lower (P < 7 x 10(-9)). The lung/liver uptake ratio of ex-smokers was significantly higher than that of nonsmokers (P < 0.005). The authors conclude that pulmonary Tc-99m HMPAO uptake of smokers is significantly diminished after quitting smoking. However, the lung uptake of ex-smokers is higher than that of non-smokers. The uptake in the lung induced by smoking appears to be partially reversible after the cessation of smoking.

Aged↗
PubMed1993

Lung uptake of Tc-99m HMPAO in cigarette smokers expressed by lung/liver activity ratio.

Tc-99m HMPAO, a lipophilic radiopharmaceutical used for brain imaging, has been reported to localize in smokers' lungs. To quantitate this uptake in the lung, 55 patients, who were referred for brain imaging for dementias or strokes, also underwent lung imaging (anterior lung imaging includes a large part of the liver) after IV injection of the radiopharmaceutical. Regions of interest over the liver and the lung were calculated. Of the 55 patients (ages 13-79), 30 were smokers and 25 were nonsmokers. The smokers had been smoking from 6-59 years, and daily cigarette consumption ranged from 8-50 cigarettes. The mean lung/liver ratio for smoking patients were 0.792 +/- 0.042 (SE); the mean lung/liver ratio for nonsmoking patients was 0.408 +/- 0.019 (SE). Lung/liver ratio uptake was significantly higher in the smoking patients (P < 0.01) than in the nonsmokers. Thus, lung/liver uptake of Tc-99m HMPAO may be used as an indicator of cigarette smoking.

Adolescent↗
PubMed1992

Investigations into the relative bioavailability of carbamazepine after single oral administration of three test batches of a carbamazepine-containing sustained release formulation in healthy subjects.

A bioavailability study with three test batches of a sustained release formulation of carbamazepine, which differed only in their in vitro dissolution profiles, was performed in 18 healthy subjects to compare the respective plasma concentration profiles and to determine the relative bioavailability of carbamazepine (CBZ). This investigation was designed to examine the extent to which these differences in dissolution properties can be determined from the results of in vivo tests. The randomized, single-dose, crossover study comprised three experimental periods, separated by washout intervals of three weeks' duration. A sensitive, validated HPLC method was used for the analysis of serum carbamazepine concentrations. Bioequivalence was only accepted if the 90% confidence interval (parametric or nonparametric) for the quotients of the mean values of the variables for each test and reference preparation was completely within the bioequivalence range. For this calculation, all three test preparations were compared with one another. The following relative bioavailability values were obtained: A/B: AUC = 87% (83%, 92%), MRT = 106% (103%, 109%), HVD = 109% (105%, 113%). C/B: AUC = 106% (101%, 110%), MRT = 98% (96%, 99%), HVD = 87% (82%, 91%). C/A: AUC = 124% (117%, 130%), MRT = 92% (89%, 94%), HVD = 79% (74%, 84%). There was a positive correlation between the in vitro dissolution rates of the different test batches and the respective degree of carbamazepine absorption as determined in vivo, while an inverse correlation existed between the in vitro dissolution rates on one side and the mean residence time (MRT) as well as the half value duration (HVD) on the other.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Pharmaceutical and biopharmaceutical quality of a sustained release carbamazepine preparation: a contribution to quality assurance.

Side effects observed during treatment with non-sustained release carbamazepine preparations are often due to the steep rise in plasma carbamazepine concentrations. To maintain plasma levels with only minor fluctuations between narrow limits, sustained release formulations have been developed which release the active constituent at a constant rate which is not too high. Bioavailability tests (single dosage, crossover design) and several investigations into the dissolution profile were carried out on three test batches of a sustained release carbamazepine preparation (Timonil 300 retard). The aim was a release model which, in the context of quality assurance, would not only facilitate reliable statements with regard to batch conformity, but would also be validated in respect of pharmacokinetic parameters such as rate of absorption and bioavailability. Correlations between mean dissolution times (MDT) and mean absorption times (MAT) at level B were found [Skelly et al. 1990]. A dissolution test differing from the pharmacopoeial tests was selected, which permitted the assessment of both batch conformity and biopharmaceutical batch quality.

Absorption↗
PubMed1983

[Auditory evoked brain stem potentials, visual pattern evoked and somatosensory evoked potentials in transient ischemic attacks (TIA)].

Auditory-evoked brainstem potentials, visual pattern-evoked and somatosensory-evoked potentials in transitory ischemic attacks (TIA). Pathological findings in patients suffering from transitory ischemic attacks by means of using neuroradiological methods (CCT included) are a rare condition. The combination of visual checkerboard-evoked potentials (VEP), auditory brainstem-evoked (AEP) and somatosensory-evoked potentials (SSEP) can detect functional lesions in cerebral regions with different blood supply but without diagnostic risk. A delay of peak III of the AEP is possibly of specific value with regard to brainstem lesion caused by TIA in our patients.

Audiometry↗
PubMed1978

[Myelography with metrizamide in children (author's transl)].

The non-ionic water-soluble contrast medium metrizamide (Amipaque) allows the examination of all regions of the spinal canal. Excellent visualization, the low toxicity for nervous tissue, and small side effects make metrizamide the best contrast medium for myelography, even in infants and children. The technique used is described and results are demonstrated.

Adolescent↗
PubMed1978

[Thoracic myelography with water-soluble contrast medium (metrizamide) (author's transl)].

The use of water-soluble contrast media for the thoracic myelography has become possible with the introduction of Metrizamide (Amipaque). A modification of the technique used with oily contrast media results in excellent demonstration of detail of intraspinal structures and of pathological changes. The medium is well tolerated and does not cause irritation of the spinal cord; the results must be regarded as excellent.

Headache↗