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Biomedical subjects

T Beck

Publications and source records attributed to T Beck.

At least 145 records · Page 8Linked to original sources
PubMed1986

The effects of tifluadom and ketazocine on behaviour, dopamine turnover in the basal ganglia and local cerebral glucose utilization of rats.

The purpose of the present study was to evaluate the interrelation between behavioural effects of kappa-opiates and cerebral neurochemical correlates in rats. Administration of the kappa-opiates tifluadom (2.5 mg/kg i.p.) or ketazocine (5 mg/kg i.p.) caused a marked initial decrease in locomotor activity lasting about 15-20 min, followed by an increase in locomotor activity at about 40 min after drug administration. At 15 min after i.p. injections of the same drugs 3,4-dihydroxyphenylacetic acid concentrations, measured by HPLC, were slightly increased in the nucleus accumbens, but unchanged in the striatum; dopamine concentrations were unchanged in both regions. The rates of glucose utilization, determined by quantitative [14C]2-deoxyglucose autoradiography, were mainly unchanged except for the nucleus accumbens, which showed an increased glucose utilization after both drugs given i.v. Tifluadom also decreased rates of glucose utilization in the caudate nucleus and parietal, sensorimotor, olfactory and frontal cortices. The above-mentioned effects on behaviour and local cerebral glucose utilization could be prevented by naloxone (3 mg/kg). The data suggest that changes in locomotor activity, neurotransmitter metabolism and neuronal activity in the nucleus accumbens are interrelated and that opiate-induced akinesia is mediated via the nucleus accumbens.

Animals↗
PubMed1986

Effects of the indirect dopaminomimetic diethylpemoline on local cerebral glucose utilization and local cerebral blood flow in the conscious rat.

The changes in local cerebral glucose utilization (LCGU) and local cerebral blood flow (LCBF) following the systemic application of the indirect dopaminomimetic diethylpemoline (50 mg/kg i.v.) were measured in conscious rats using the autoradiographic [14C]2-deoxyglucose and the [14C] iodoantipyrine technique. Increased rates of glucose utilization were observed in the sensorimotor cortex, parafascicular nucleus, ventrolateral nucleus of the thalamus, substantia nigra, caudate nucleus, globus pallidus, red nucleus, subthalamic nucleus, cerebellar cortex and vermis. Cingulate cortex, anteromedial, anteroventral nucleus of the thalamus, habenula and nucleus accumbens showed a decreased LCGU. The determination of LCBF revealed a similar pattern of altered blood flow values. Statistical evaluation of the relationship between glucose utilization and blood flow by regression analysis did not reveal any distinguishable difference between diethylpemoline-treated rats and controls. The data suggest that it is mainly the altered neuronal activity and metabolic demand after dopaminergic stimulation that effect the changes in blood flow rather than a direct dopaminergic effect on brain vasculature.

Animals↗
PubMed1986

Immunohistochemical location of HPL, SP1 and beta-HCG in normal placentas of varying gestational age.

Sixty-four placentas at various gestational ages were examined by immunohistochemical stains for HPL, SP1 and beta-HCG according to a modified PAP method (Sternberger 1970). Syncytiotrophoblast cell layer was identified as the main site of synthesis. Extravillous immunohistochemical reactions for HPL and SP1 (but not for beta-HCG) were found in X-cells of the basal plate and in the intervillous trophoblast islands. These cell types would thus seem to be derived from trophoblast. Hofbauer-cells of villous connective tissue stained specifically for beta-HCG apparently because of HCG phagocytosis. The intensity of staining for HPL, SP1 and beta-HCG was evaluated semiquantitatively in the syncytiotrophoblast cell layer at various gestational weeks. The maximum of staining for beta-HCG was found in the uniform syncytiotrophoblast layer of immature intermediate villi in early pregnancy (7-14 weeks), HPL and SP1 had their peak of staining reaction at 32-36 weeks of gestation. Increasing maturation results in a subspecialisation of the villous surface: epithelial plates (allowing feto maternal exchange) and nucleated portions of syncytiotrophoblast (which are the main site of hormone production and endocrine activity).

Chorionic Gonadotropin↗
PubMed1986

Morphology of placental villi after premature delivery and its clinical relevance.

Based on a new concept of maturation of the placental villous tree and its disorders (synchronous and asynchronous immaturity, asynchronous maturity, hypermaturity, and terminal villi deficiency) we studied the possible effect of the placental villous tree on the premature onset of labour. In mature normal neonates irregular and asynchronous villous patterns were found in 50% of cases. In prematurely delivered neonates, only 33% of the corresponding placentas show synchronous immature villous patterns. Uterine bleeding in the first trimester was associated with a 42% of incidence of premature maturation of the villous tree. These findings strengthen the idea that hormonal imbalance in early pregnancy influenced villous development. In "prematurity without recognizable cause" there was a higher percentage of villous maldevelopment (33%) than that previously described in the literature. In severe pre-eclampsia combined with premature onset of labour, 60% of our cases showed hypermaturity of the villous trees. Synchronous immaturity was reduced to 15%. We conclude, that even a rather rough definition of the histological features of placental villi is sufficient to produce numerous correlations between clinical events preceding premature delivery and placental structure. So the influence of placenta on the premature onset of labour needs more attention.

Chorionic Villi↗
PubMed1986

[Monoclonal antibodies for the immunohistochemical detection of estrogen receptor status in tissue sections of primary breast cancers].

The article reports on first experiences with immunohistochemical staining methods (ER-ICA and ER-D5) using monoclonal antibodies for determination of oestrogen receptor status in tissue slides. 95 primary breast cancers were analysed by ER-ICA; in addition, a subgroup of 31 cases was stained for ER-D5. The results of the two immunohistochemical procedures revealed a large measure of agreement with the standard ligand binding assay. The evaluation of the immunohistochemical staining reaction led to the formation of a staining Score: Score points of ER-ICA, not those of ER-D5, revealed good correlation with oestrogen receptor concentrations in cytosol, determined by standard ligand binding assay. The used staining Score was examined for intra- and inter-individual differences of evaluation and proved to be well reproducible. Further clinical studies have to prove how far immunohistochemical features can convey clinically relevant information not yielded by the steroid binding assay.

Antibodies, Monoclonal↗
PubMed1986

Comparison of immunocytochemical estrogen receptor assay, estrogen receptor enzyme immunoassay, and radioligand-labeled estrogen receptor assay in human breast cancer and uterine tissue.

Determination of estrogen receptor content in 82 breast cancer specimens with immunocytochemical estrogen receptor assay (ER-EIA) (Abbott) was compared with our routinely used binding assay using 125I-estradiol as radioligand with Scatchard plot analysis of the binding data. Although the estrogen receptor content measured with the ER-EIA was approximately 2-fold higher compared with the binding assay, the immunochemical method proved to be a useful alternative for estrogen receptor determination. Furthermore, it is possible to detect estrogen receptors in FPLC Superose 12 (size exclusion column) eluates or in the fractions obtained after sucrose density centrifugation using the ER-EIA. Forty breast cancer samples were analyzed utilizing the immunocytochemical technique (ER-ICA) for visualization of the estrogen receptor content in frozen tumor tissues in relationship to the quantitative results obtained with the ER-EIA assay. Specific staining for estrogen receptor was confined only to the cell nucleus, was distributed irregularly among the tumor cells, and was variable in intensity. The staining intensity and the percentage of positively stained cells increased with increasing level of cytosolic estrogen receptor. In 27 of 40 cases the immunocytochemical results correlated well with the ER-EIA assay. Nine cases were ER-ICA negative with positive ER-EIA, and four were ER-ICA positive with negative ER-EIA.

Breast Neoplasms↗
PubMed1985

Right ventricular ejection fraction measured by first-pass intravenous krypton-81m: reproducibility and comparison with technetium-99m.

Study of the effects of various diseases and therapeutic manipulation of pulmonary vascular resistance on the right ventricle has been restricted by methodologic limitations. The radioactive gas in solution, krypton-81m was used to study the right ventricle and the technique was compared with a technetium-99m method. In 22 subjects, first-pass krypton-81m right ventricular ejection fraction, acquired both in list mode and electrocardiogram-gated frame mode, correlated well (r = 0.81 and 0.86, respectively, p less than 0.01) with that determined by technetium-99m first-pass studies over a broad range of ventricular function. The reproducibility of the technique was excellent (r = 0.84 and 0.95 for each acquisition mode, respectively). Krypton-81m first-pass studies provide accurate and reproducible estimates of right ventricular function. Use of krypton allows multiple measurements, with or without perturbations, over a short period of time.

Heart Ventricles↗
PubMed1985

Comparison of oxygen consumption, carbon dioxide production, and resting energy expenditure in premature and full-term infants.

A newly developed closed circuit water-sealed infant calorimeter has been used to measure oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory quotient (RQ) and resting energy expenditure (REE) in 31 infants. There were 17 full-term and 14 premature infants. VO2 was measured volumetrically, keeping the inspired oxygen concentration constant. VCO2 was determined by infrared analysis of the mixed expired gases. Values for REE and RQ were calculated from measurements of VO2 and VCO2. All values were normalized for the infants body weight. Our findings demonstrate significant differences in VO2, VCO2, and REE associated with weight, gestational age, postnatal age, activity, feeding, and sex. In addition, VO2, VCO2, and REE were significantly higher for the premature infants. The water-sealed indirect calorimetry system: (a) is safe and noninvasive, (b) does not interfere with infant tube feeding or IV infusion, (c) permits long-term monitoring of metabolic activity, and (d) allows a more exact matching of oral and intravenous feedings to actual energy expenditure. We are finding that indirect calorimetry removes the guess work from writing daily caloric regimens, with potential advantage for the treatment of sick infants.

Calorimetry, Indirect↗
PubMed1985

Characterization of a high-affinity, low-capacity androgen binding protein in human term placental cytosol.

A high-affinity, low-capacity androgen binding component in human placental cytosol was characterized. (3H)-R1881, a synthetic androgen, was used as radioactive ligand for characterization and quantification of this placental androgen binding component. Various naturally occurring as well as synthetic steroids were first investigated for their in vitro stability under receptor assay conditions (i.e., an overnight incubation at 4 degrees C). Only the synthetic steroids were found to be metabolically stable. The rate constant of dissociation was found to be 6.42 X 10(-4) s-1 (on the basis of k-1 the rate constant of association was 1.27 X 10(5) M-1 s-1). The concentration of androgen binding protein was measured in 50 human term placentae. The mean concentration was 169 +/- 132 fmol/mg protein, and the average Kd was 5.07 +/- 2.2 X 10(-9) M. Placentae of female fetuses contained significantly higher concentrations (219 +/- 140 fmoles/mg protein) than those of male fetuses (115.2 +/- 101 fmoles/mg protein). The (3H)-R1881-androgen binding protein complex exhibited a sedimentation coefficient of 4S under low salt conditions. The binding site was only specific for androgens and progestins but not for steroids of other classes.

Androgen-Binding Protein↗
PubMed1985

[Metastatic breast cancer with involvement of the bone marrow, uterus and ovaries. A case report on diagnostic and therapeutic procedures].

The article reports on a clinically unusual case of a patient with carcinoma of the breast. The "initial sign" of the disease was relapsed hypermenorrhoic permanent bleeding with severe bleeding anaemia caused by a metastatic growth in the uterus. Surgery or cytostatic treatment did not seem possible at the outset, because thrombocytopenia (21,000/nl) progressed rapidly, associated with disseminated bone marrow metastases. The diagnostic and therapeutic procedure is described and discussed.

Adult↗
PubMed1984

Peanut lectin histochemistry of 120 mammary carcinomas and its relation to tumor type, grading, staging, and receptor status.

Peanut lectin (PNL) is known to bind beta-D-galactosyl-(1-3)-N-acetyl-D-galactosamine, which provides antigenic determination of the Thomsen-Friedenreich antigen ( TFAg ). The aim of this study was to analyse the expression of peanut lectin binding sites in mammary carcinomas and to correlate these with tumor type, histological grading, staging and biochemical receptor status. The series comprised 120 invasive mammary carcinomas and 14 cases with normal breast tissue or benign epithelial proliferations as controls. In controls mainly luminal or apical PNL-binding was discovered, however, in all except three carcinomas a cytoplasmatic localisation of TFAg with three major patterns was found: diffuse, granular-globular and vacuolar reactions. The quantitative-qualitative evaluation of the PNL-staining revealed a statistically significant correlation between globular-vacuolar PNL-reaction and tumor type with a higher percentage of this type of reaction in invasive lobular carcinomas as opposed to tubular and invasive ductal carcinomas. Furthermore a statistically significant relationship was disclosed between PNL- histopositivity and estrogen positive - progesterone positive cases. However, the findings of contradictory PNL-status and hormone-receptor status illustrates clearly the difficulty of predicting the biochemical receptor status. No correlation was found between PNL-histochemistry, histological grading, and pathological staging. The practical implications of PNL-histochemistry of mammary carcinomas are discussed.

Arachis↗
PubMed1984

Neomorphogenesis of blood vessels in rabbit skin induced by a highly purified monocyte-derived polypeptide (monocyto-angiotropin) and associated tissue reactions.

Chemotropic morphogenesis of new blood vessel patterns with active haemodynamics in the skin of rabbits was induced by intradermal injection of highly purified monocyto-angiotropin (MAT), one of the low-molecular-weight (4,500) polypeptide monokines exuded by activated mammalian (porcine) monocytes (macrophage type) on their culture in serum-free, fully synthetic media. Evidence is presented that neohypervascularization of the skin is associated with enhanced tissue function as represented by hair growth. Exclusively in the area of MAT injection, numerous capillary-like vessel formations arose from preexisting vessels, and the quiescent hair follicles (telogen) were activated to growing ones (anagen) within 1-2 weeks.

Animals↗
PubMed1983

Interaction of alpha 2-macroglobulin with trypsin, chymotrypsin, plasmin, and papain.

The interaction alpha 2-macroglobulin with four proteinases has been investigated by binding assays and by gel electrophoresis. At pH 7.65 the binding ratios of the proteinase-alpha 2-macroglobulin complexes were found to be 2:1 (trypsin and papain), 1.4:1 (chymotrypsin), and 1:1 (plasmin). The progressive decrease in the stoichiometry of the three seryl proteinase complexes was paralleled by a concomitant decrease in the proteinase-dependent specific cleavage of the alpha 2-macroglobulin peptide chains. Rate studies have shown that the relative rates of reaction of the proteinases with alpha 2-macroglobulin also varied greatly: papain greater than trypsin greater than chymotrypsin greater than plasmin. The data suggest that the ability of a proteinase to saturate the second proteinase binding site is a reflection of its ability to bind to alpha 2-macroglobulin and cleave the second pair of scissile alpha 2-macroglobulin peptide bonds before the alpha 2-macroglobulin has undergone the conformational change initiated by the formation of the 1:1 proteinase alpha 2-macroglobulin complex.

Chymotrypsin↗