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Biomedical subjects

S Strauss

Publications and source records attributed to S Strauss.

At least 109 records · Page 6Linked to original sources
PubMed1986

Diazepam attenuates the antagonism of haloperidol against apomorphine-induced stereotypic behavior after subchronic but not acute treatment in rats.

Apomorphine-induced stereotypic behavior was investigated in rats treated with diazepam or haloperidol and with the combination of both drugs in a one day trial or subchronically. The drugs were administered via the drinking water. Diazepam dose-dependently reduced apomorphine stereotypies after the subchronic (6 days) but not after the acute treatment. Haloperidol suppressed apomorphine-induced stereotypic behavior dose-dependently after acute as well as after subchronic administration apparently without the development of tolerance. This discrepancy to other studies may be explained by the concomitant increase in maximum number of D2-receptors in the striatum. The apomorphine antagonistic effect of haloperidol was attenuated when the neuroleptic was administered subchronically in combination with the benzodiazepine. This finding was unexpected since both drugs reduced apomorphine-induced stereotypic behavior when administered alone. The further increase in maximum number of D2-receptors due to combined treatment with low doses of diazepam, suggesting a sort of "over adaptation", possibly explains the haloperidol-antagonistic action of diazepam in the behavioral experiments. Binding studies on dopamine (D1), 5-hydroxytryptamine (5-HT2) and benzodiazepine receptors revealed that modification of the apomorphine-induced stereotypies by the combined treatment with haloperidol and diazepam cannot be explained by interactions of the drugs at the level of the D1, 5-HT2 or benzodiazepine-receptors.

Animals↗
PubMed1986

Renal sonography in American Burkitt lymphoma.

Renal involvement is a common finding at necropsy in patients with American Burkitt lymphoma, but its in vivo sonographic features have received little attention in the literature. Of 29 patients with American Burkitt lymphoma who underwent sonography, 10 were found to have renal involvement. The 10 patients demonstrated a range of abnormalities, notably renomegaly (nine patients), diffuse increase in cortical echogenicity (six), and focal renal masses (three). The focal infiltrations were, unexplicably, hypoechoic in two patients and hyperechoic in one. Hydronephrosis was seen in five patients. One patient had evidence of calcium phosphate renal stones. Response to therapy can be assessed by changes in renal size and cortical echogenicity, as well as disappearance of focal lesions.

Adolescent↗
PubMed1985

Neuroleptics and beta-carbolines displace (3H)Imipramine from its binding sites in human and rat tissues.

Most investigations dealing with the pharmacological characterization of (3H)imipramine binding sites focus on tricyclic antidepressants (TCA). This approach seemed to be justified since imipramine belongs to that chemical group. Langer and coworkers, however, introduced a tetrahydro-beta-carboline (TH beta C) as a possible endogenous ligand. Thus, the high affinity of imipramine towards the binding sites might not be due to its special chemical structure but due to its tricyclic nature. In the present paper the structure-activity-relationships of neuroleptics and beta-carbolines were investigated and compared with that of tricyclic antidepressants. Among the tricyclic neuroleptics those with an electron attracting substituent (-Cl) exerted highest affinity. The effect was attenuated by a long, cyclic side chain. The affinity of tricyclic neuroleptics was only slightly weaker than that of 6-Meo-TH beta C the suggested endogenous ligand. The experiments with other TH beta Cs supported the observation that an electron attracting substituent increases the affinity of a compound to the (3H)imipramine binding sites. Comparison of the binding characteristics of (3H)imipramine to membranes of human brain and thrombocytes as well as those of rat brain and thrombocytes revealed no differences among both species. Furthermore, the displacing potencies of neuroleptics were very similar with only slightly more activity in human tissue. As a methodological aspect the applicability of the "Lowry" method to determine the protein concentration is discussed.

Aged↗
PubMed1985

Nonproductive kappa immunoglobulin genes: recombinational abnormalities and other lesions affecting transcription, RNA processing, turnover, and translation.

Six nonproductive kappa immunoglobulin genes (kappa- alleles) were cloned and sequenced. The structural abnormalities discerned from sequence analysis were correlated with functional lesions at the level of transcription, RNA processing, turnover, and translation. Four kappa- alleles, three containing V kappa genes and one not, are transcribed at normal or even greater than normal rates, the defects in these genes being expressed at various posttranscriptional levels. The other two kappa- alleles, both of which lacked V genes, exhibited greatly depressed yet clearly detectable transcriptional activity. These results are consistent with a hierarchical relationship between enhancer and promoter elements in which the enhancer establishes transcriptional competence at the kappa locus and the promoter (or pseudopromoter) determines the relative level of transcriptional activity. One of the structural abnormalities discovered in this study, a large deletion which removes the entire J kappa region, also provides new insight into the mechanism of VJ and VDJ recombination.

Alleles↗
PubMed1985

Sonography of periventricular leukomalacia.

Periventricular leukomalacia (PVL) is a pathological entity characterized by ischemic changes in areas adjacent to the external angles of the lateral ventricles. It is associated with serious neurodevelopmental sequelae, especially spastic diplegia. With the increased use of ultrasound in the Neonatal Intensive Care Unit, changes consistent with PVL are being noted. Hemorrhagic and nonhemorrhagic forms of this condition exist, both of which may appear sonographically as increased periventricular echogenicity. Two cases of PVL are described; one of them was associated with ventricular dilatation and intraventricular bleeding and the other with a small subependymal hemorrhage. The pathological and clinical features, methods of in vivo diagnosis, and the role of ultrasound in the evaluation of PVL are discussed.

Brain Diseases↗
PubMed1985

Transient obstruction of the kidney and hypertension due to neonatal adrenal hemorrhage. Case report.

A case of neonatal adrenal hemorrhage associated with transient obstruction of the kidney and hypertension is reported. Sonography demonstrated a mass in the right suprarenal area, consistent with hemorrhage into the adrenal gland. DTPA renal scan showed prolonged retention of the injected material in the right kidney, consistent with obstructed outflow from the renal collecting system. Gradual decrease in the size of the suprarenal mass was associated with relief of the renal obstruction as evidenced by a normal repeat renal scan, and a return to normal of the blood pressure. It appears that the cause for the hypertension was the acute renal obstruction, which was due to either direct pressure on the proximal ureter by a large adrenal mass or secondary to displacement of the kidney by the mass resulting in kinking of the proximal ureter.

Adrenal Gland Diseases↗
PubMed1984

Ethanol induces an increase of harman in the brain and urine of rats.

Harman occurs in rat brain, with the highest concentration in the cerebellum and the lowest in the striatum. 2 g/kg ethanol were ineffective with respect to the concentration of harman in the brain whereas 5 g/kg ethanol caused a time-dependent increase in the cerebral cortex as well as the cerebellum. A toxic dose (8 g/kg) of ethanol elicited no change of harman in the brain 3 h following the application. The rise in the harman concentration in the brain did not correlate with the increase of acetaldehyde in the blood after treatment with ethanol suggesting that several mechanisms are involved in the changes of the levels of harman. In subchronic experiments rats were treated with ethanol over a period of 5 or 6 days. Harman increased in the brain whereby the effect seemed to be more pronounced in the cerebellum than in the cerebral cortex. The concentration tended to increase over time and reached control levels again during withdrawal. The time course of the excretion of harman into the urine was similar to that of the brain in that it increased continuously during the period of ethanol treatment and reached control levels again during withdrawal.

Acetaldehyde↗
PubMed1984

The pylorus in infancy: overall sonographic assessment.

A prospective ultrasonic evaluation of the pylorus was performed in two groups of infants, a control group and a group of infants clinically suspected of having hypertrophic pyloric stenosis (HPS). The mean pyloric length in the hypertrophied condition was 84% longer than the mean length in the normal. The mean and standard deviation (sd) for the transverse diameter and pyloric wall thickness in the normals were 7.45 +/- 2.2 mm and 2.3 +/- 0.7 mm respectively, while the corresponding measurements for the mean and sd in HPS were 13.4 +/- 1.6 mm and 4.5 +/- 0.9 mm. In most of the HPS cases the known morphological changes of the antro-pyloric region such as: impingement on the fluid filled antrum, pre-pyloric antral thickening, extension of fluid into the proximal portion of the pyloric canal and the angle formed between antral peristaltic wave and pyloric mass, were observed. Detection of these changes furnished further criteria for highly accurate diagnosis of HPS even of borderline cases.

Female↗
PubMed1984

Hyperechoic foci in the gallbladder wall as a sign of microabscess formation or diverticula.

Abdominal sonography in 7 patients with acute biliary disease revealed focal echo collections within the wall of the gallbladder in addition to cholelithiasis and diffuse mural thickening. A prospective study was conducted, comparing in vivo and in vitro sonography of the gallbladder with histopathological findings. In 3 patients, microscopy of the hyperchoic tissue showed microabscesses. In 4, intramural diverticula containing inspissated bile, small stones, or cholesterol crystals were seen. The authors caution that hyperchoic foci within the wall of the gallbladder may indicate intrinsic disease separate from cholelithiasis or cholecystitis.

Abscess↗
PubMed1984

Torsion of the ovary: sonographic features.

The sonographic findings in 19 cases of surgically proven torsion of the ovary are described. In all cases the affected ovary was markedly enlarged; in 32% of cases a small amount of fluid was detected in the cul-de-sac. More significant in terms of specificity was the demonstration in 14 (74%) of the 19 cases of small cystic structures scattered around the periphery of the organ. Sonographic demonstration of these structures, presumably prominent follicles, can suggest the preoperative diagnosis of ovarian torsion.

Adult↗
PubMed1983

Pharmacokinetics of tetrahydronorharmane (tetrahydro-beta-carboline) in rats.

The distribution, metabolism and elimination into the urine of (14C)-tetrahydronorharmane (THN) as well as of (14C)-6-hydroxy-tetrahydronorharmane (6-OH-THN) are investigated in female and male rats. Following intravenous injection of (14C)-THN radioactivity was detected in all organs examined, namely blood, brain, lung, adrenal gland, small intestine, fat tissue, kidney and liver. In the brain the elimination half life of THN was calculated to be 1.8 h, the elimination half life of the radioactivity in the blood 6.24 h, and the accumulation half life in the urine 9.24 h. The elimination of 6-OH-THN into the urine is faster than that of THN. At least four metabolites of (14C)-THN were found in the urine of female rats. Two different metabolic pathways are discussed, firstly, hydroxylation followed by conjugation with glucuronic and sulfuric acids and secondly, dehydrogenation, followed by oxygenation. In female rats only traces of the conjugated metabolites are hydrolysed by arylsulfatase, whereas in male rats approximately 2/5 are cleaved by this enzyme. Pretreatment of male rats with 3-methylcholanthrene induced conjugation, whereas phenobarbital had no obvious effect on the pattern of metabolites. SKF 525 A and CFT 1201 both prevented almost completely the formation of conjugates from THN.

Alkaloids↗