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T Beck

Publications and source records attributed to T Beck.

At least 19 recordsLinked to original sources
PubMed1992

Morphological, immunohistochemical and biochemical characterization of 6 newly established human ovarian carcinoma cell lines.

Six permanent human tumor cell lines (OV-MZ-1 to 6) were established from 6 patients with serous adenocarcinomas of the ovary. These cell lines were derived from both solid tumors and ascites, from pre-treated and untreated patients, and are available over a range of in vitro passage numbers. The tumor cells grow as monolayers and develop foci of "piled-up' cells in confluent cultures. Flow cytophotometry showed that all the lines exhibited DNA hyperdiploidy with DNA tetraploidy in one cell line and DNA aneuploidy in the other cell lines. The mean population doubling time ranged from 24 to 52 hr. Transmission electron microscopy demonstrated that the tumor cells of all cell lines exhibited features of epithelial differentiation such as desmosomes and intracellular gland-like lumina. Immunocytochemical analysis showed that the co-expression of cytokeratins and vimentin, which is a feature of ovarian serous cystadenocarcinomas in situ, was fully preserved in the majority of cell lines. The main cytokeratin polypeptides expressed were numbers 7, 8, 17, 18 and 19. The tumor-associated antigen CA-125, but not CEA, was shed in the culture supernatant. This was in accordance with FACScan analysis of the cell lines and the level of CA-125 and CEA in the patients' serum. The estrogen and progesterone receptors were negative both in the cell lines and in the original tumors. These new ovarian carcinoma cell lines will be valuable models for further investigations into a variety of biological properties.

Adult↗
PubMed1992

Chronic infusion of nerve growth factor does not rescue pyramidal cells after transient forebrain ischemia in the rat.

Male Wistar rats received chronic intracerebroventricular infusions of nerve growth factor (NGF) starting immediately before induction of a transient forebrain ischemia and continuing until 7 days after the infarct. Ischemia was induced by carotid occlusion and simultaneous hypotension. Seven days after the infarct the brains were examined histologically and the number of necrotic cells in the hippocampus were counted. The results did not reveal any difference in treated vs. untreated animals. The data suggest that application of exogenous NGF does not prevent ischemic cell death in the hippocampus.

Animals↗
PubMed1992

C-erbB-2-oncogene expression in breast carcinoma: analysis by S1 nuclease protection assay and immunohistochemistry in relation to clinical parameters.

The c-erbB-2 mRNA was detected by the S1 nuclease protection assay and Northern blotting in breast cancer tissues. In contrast to the Northern blot analysis which has been used in all recent publications concerning c-erbB-2 expression on the level of RNA, the S1-nuclease protection assay has distinct advantages with respect to sensitivity, reproducibility, and handling of radioactive probes. We compared the expression of c-erbB-2 in 120 breast carcinomas which were operated in the years 1989-1990 on the level of the mRNA (S1 nuclease protection assay) and the protein (immunohistochemistry), respectively. In general, results obtained with both methods were in good agreement. Only minor differences in classification were observed with 18 samples, all of them belonging to either the moderate or the weak c-erbB-2 expression phenotype. In addition, the level of c-erbB-2-protein was investigated by immunohistochemistry in 271 breast carcinomas which were operated in the years 1984-1987. Comparison of the level of c-erbB-2 expression with the patient history indicates that patients whose tumors had already metastasized to the axillary nodes showed a reduced overall and disease-free survival in the group with pronounced expression of the c-erbB-2 protein. Thus the strong expression of c-erbB-2 oncogene in primary breast cancers appears to be an additional and particular prognostic factor in lymph node positive patients.

Blotting, Northern↗
PubMed1992

[Placental morphometry in diastolic zero and negative flow of the umbilical arteries].

Macromorphometric and histometric placental data, in cases with enddiastolic zero flow or reverse flow (dZRF), reveal a lower placental weight and smaller attachment area as well as bigger terminal villi with a reduced amount of epithelial plates with comparable vascularisation. In cases with reverse flow, all parameters were worse, either compared to the controls or to the zero flow cases. With advancing duration of clinical observation, we find a maturation of the terminal villi, with the cross-sectional areas getting smaller, diffusion distances becoming shorter and vessels bigger. This proves the dependence of foetal outcome by dZRF on the compensatory capacity of the terminal villi. The planimetric area in the forward flow channel depends on the foetal intravillous blood volume.

Blood Flow Velocity↗
PubMed1992

Infarct reduction by the platelet activating factor antagonist apafant in rats.

BACKGROUND AND PURPOSE: Recent findings suggest a key role for platelet activating factor in neuroinjury. For this reason we evaluated the effects of the platelet activating factor antagonist apafant (4-(2-chlorophenyl)-9-methyl-2[3(4-morpholinyl)-3-propanol-1- yl[6H-thieno[3.2-f[[1.2.4]triazolo]4,3-1]]1.4]diazepine on farct volume and local cerebral blood flow following irreversible occlusion of the left middle cerebral artery in rats to assess the direct and vascular components of apafant's action. METHODS: We measured infarct volume 48 hours after middle cerebral artery occlusion. The effect of multiple doses of apafant (30 mg/kg p.o.) was tested in both pretreatment (n = 8) and posttreatment (n = 8) groups. In the pretreatment group apafant was given 30 minutes before and 2, 6, and 18 hours after occlusion. Rats of the posttreatment group received apafant 1, 6, and 18 hours after middle cerebral artery occlusion. We also examined the effect of a single dose of apafant given 30 minutes prior to occlusion (n = 9) on local cerebral blood flow determined 2 hours after middle cerebral artery occlusion. RESULTS: Both regimens of apafant effectively decreased infarct volume. The reduction in cortical infarct volume was 59% (p less than 0.01; H test, U test) when the rats were treated before and after vessel occlusion whereas the decrease was 47% (p less than 0.05; H test, U test) when treatment began 1 hour after occlusion. Apafant did not change local cerebral blood flow after occlusion compared with controls. CONCLUSIONS: We suggest that the cytoprotection afforded by apafant occurs mainly via a direct effect on brain tissue and has no major vascular component.

Animals↗
PubMed1992

The effect of antenatal intravenous immunoglobulin on ascending intrauterine infection after preterm premature rupture of the membranes: a pilot study.

Ascending infection is a serious threat in pregnancies complicated by preterm premature rupture of the membranes (PROM). In a controlled randomized prospective pilot study (n = 18) we have evaluated the effect of intravenous IgM enriched immunoglobulin given to the mothers 24-48 hours after preterm PROM in reducing ascending infection. Using a validated infection score from laboratory and clinical data at birth, we found a significant reduction of probable infection in the neonates of the treatment group compared to the control group (p = 0.0022). Histopathological investigation of the placentas, membranes and umbilical cords revealed significantly lower stages and grades of chorioamnionitis in the treatment group (p = 0.036). From these preliminary results we conclude, that intravenous broad spectrum immunoglobulin given antenatally to patients with preterm PROM may reduce ascending infection. However, studies with a much larger cohort of patients are necessary to confirm these preliminary results and to detect potential clinical benefits from this treatment mode.

Adult↗
PubMed1991

The effects of two 21-aminosteroids on overt infarct size 48 hours after middle cerebral artery occlusion in the rat.

The lipid peroxidation inhibitors U74006F (21-[4-(2,6-di-1-pyrrolidinyl-4-pyrimidinyl)-1-piperazinyl]-16 alpha-methylpregna-1,4,9]-(11)-triene-3, 20-dione) and U74512E (21-[4-(3-ethylamino-2-pyridinyl)-1-piperazinyl]-16 alpha-methylpregna- 1,4,9]-(11)-triene-3,20-dione) were tested for cerebroprotective properties in the rat. Focal cerebral ischemia was induced by irreversible occlusion of the middle cerebral artery (MCA-O). The 21-aminosteroids U74006F (1 mg/kg or 10 mg/kg, i.p.) and U75412E (1 mg/kg or 30 mg/kg, i.p.) were injected 30 min prior and 2, 6, and 24 h after MCA-O. The higher doses of U74006F or U75412E caused reductions in cortical infarct size ranging from 28 to 34%. The data suggest the 21-aminosteroids to be mildly effective after irreversible occlusion of the MCA but possibly to be more beneficial as part of a combined drug therapy in conjunction with Ca2+ or NMDA antagonists.

Animals↗
PubMed1991

The effects of dizocilpine (MK-801), phencyclidine, and nimodipine on infarct size 48 h after middle cerebral artery occlusion in the rat.

The effects of the calcium channel blocker nimodipine and the non-competitive NMDA-antagonists MK-801 and phencyclidine (PCP) on infarct size 48 h after occlusion of the middle cerebral artery (MCA-O) were evaluated in the rat. Nimodipine was given at a dose of 0.3 mg/kg s.c. 30 min prior and 8, 16, and 24 h after MCA-O. MK-801 (1 mg/kg i.p. or 10 mg/kg i.p.) or PCP (0.3, 1.0, 3.0, 10, or 30 mg/kg i.p.) were administered 30 min prior to ischemia. In additional experiments 30 mg/kg PCP was given 1, 3, or 5 h post ischemia. Nimodipine and 1 mg/kg MK-801 reduced cortical infarct volumes significantly by 50% and 55%, respectively, while cortical infarct size fell by 32% and total infarct volume was not altered significantly after administration of 10 mg/kg MK-801. Pretreatment with 10 or 30 mg/kg PCP reduced cortical infarction by 47-53% and total infarct volumes by 39-42%. Posttreatment with PCP was effective if started at 1 or 3 h post ischemia.

Animals↗
PubMed1991

Immunohistochemical evaluation of growth fractions in human breast cancers using monoclonal antibody Ki-67.

We performed immunohistochemical analyses of 568 breast/cancer specimens using Ki-67, a monoclonal antibody specific for a nuclear antigen present in proliferating cells. The specimens were divided into three groups (I-III) according to the proportion of Ki-positive cells detected. These findings were compared with features of tumor extension as well as with certain prognostic variables. There was no detectable correlation between Ki-67 reactivity and either tumor size or node involvement. In contrast, a statistically significant correlation was found between Ki-67 reactivity and tumor grading, in that G-I tumors had small growth fractions, while a high proportion of G-III tumors exhibited strong (group III) Ki-67 positivity. When growth fractions were compared with biochemical receptor status, a significant difference was detected between tumors with negative and positive findings for receptors. The same co-variation was observed with respect to the overexpression of neu-protein P185, with most neu-positive carcinomas being strongly positive for Ki-67 (group III). In the relapse cases examined, there was a close correspondence between Ki-67 reactivity and the duration of the disease-free period. Long-term observation of patients with primary breast carcinoma revealed that, with regard to overall survival, the less reactive groups I and II differed significantly from group III. With respect to disease-free survival, no difference was detectable between Ki-groups II and III, but when these two groups together were compared with group I, a significant trend emerged. Similar results for both overall and disease-free survival were obtained for subgroups of pT2 and G-II carcinomas as well as for receptor expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1991

Placental morphometry using a computer assisted measuring programme: reference values for normal pregnancies at term.

Using the principle that the human placenta is anatomically composed of fetomaternal flow units, we developed a computer-assisted measurement programme capable of recording complex histometric data about the characteristics of the maturation and structural differentiation of resorption villi, as well as subjecting the results to simultaneous statistical processing. Using 42 placentas obtained after normal pregnancies, reference values were derived for the five primary geometrical and six further arithmetical parameters. From these findings, we also calculated the total resorption villi surface area, the proportion of this surface area occupied by epithelial plates, and the resorption-villi surface are relative to the birth weight of the child. Our findings are compared with other available results, and the reasons for discrepancies between previously published measurements are discussed.

Birth Weight↗
PubMed1991

Post-traumatic spinal cord cysts evaluated by magnetic resonance imaging.

In order to determine a more accurate prevalence of post-traumatic spinal cord cysts (PTSCC) in spinal cord injured (SCI) patients, we retrospectively reviewed magnetic resonance scans from symptomatic imaging and asymptomatic SCI patients. We found the incidence of PTSCC to be 51% in our patient population. The only symptom that correlated to the presence of a cyst was spasticity. The cyst develops at the site of injury and appears to be a common sequela of SCI. We believe that conservative treatment is indicated in most patients with a PTSCC.

Adolescent↗
PubMed1991

[Intra-arterial preoperative chemotherapy of advanced cervix cancer].

Three patients suffering from very advanced primary cancers of the cervix uteri (FIGO II B or III B) were treated. By preoperative selective perfusion of both uterine arteries, using cis-platinum alone, a distinct reduction of the tumour volume was achieved. This was demonstrated clinically and also by CAT scan and NMR technique. The elevated serum CEA and SCC levels decreased to normal values. The histomorphology of the Wertheim-Meigs specimens revealed no tumour invasion of the initially infiltrated parametria. This treatment modality has been developed to minimise the toxic side effects of the inductive (neo-adjuvant) chemotherapy for cervical cancers.

Adult↗
PubMed1991

[Placental maturity at term and functional placental performance: CTG changes in relation to histologic detection of placental maturation reserves].

Cardiotocography (CTG) is to be considered today's most sensitive monitoring tool for the functional surveillance of placental performance during parturition. 351 cardiotocographically monitored singleton pregnancies were used as patient material for fine tissue examination of the state of maturity of the villi of the relevant placentas. In histological assessment, placental diagnoses are allocated to defined CTG changes; in particular, however, the identification of reserves, capable of maturing (immature intermediate villi in the centres of the placental subdivisions or placentones), is subject to separate scrutiny. The following results emerge clearly: terminal placentas without maturing potentials, prematurely matured placentas and placentas with deficiency of terminal villi, as well as the absence of immature intermediate villi in the centers of the placentones, are connected with a suspected prepathological or pathological CTG assessment. The histological groups have the lowest incidence of the normal oscillatory type and normal oscillatory frequency and have the highest proportion of abnormal CTG assessments according to the Hammacher score. The absence of the identification of potential maturing reserves (immature intermediate villi) is associated with the highest incidence of Caesarean sections (29.8%). These results show, that the physiological maturing potentials (immature intermediate villi) which can be identified up to term are a histological indication towards regular placental performance, even in labour.

Cardiotocography↗
PubMed1991

Listeria monocytogenes isolates can be classified into two major types according to the sequence of the listeriolysin gene.

The nucleotide sequence of a 3.5-kb BamHI fragment from Listeria monocytogenes 12067, a human clinical isolate of serotype 4b, has been determined. The DNA fragment harbors the gene for listeriolysin, part of the gene for a phosphatidylinositol-specific phospholipase C, and part of the gene for a metalloprotease. Comparison of the sequence with corresponding sequences from two other L. monocytogenes isolates revealed a significant number of nucleotide differences. Several of the differences give rise to amino acid substitutions. The most variable region was the examined part of the mpl gene, whereas the lisA gene showed a relatively high degree of conservation, particularly at the amino acid level. To analyze the pattern of sequence variability in the lisA gene, a 160-bp region covering nine nucleotide differences was sequenced from 36 isolates of different origins. This work showed that the strains can be grouped into two major types according to the nucleotide sequences. Oligonucleotide probing of a larger number of L. monocytogenes isolates showed that the observed differences can be used to subdivide the species. The data suggest a correspondence between the sequence type of the lisA gene and flagellar antigens. Assays based on hybridization or the polymerase chain reaction with type-specific oligonucleotides may provide fast and easy alternative methods for strain typing.

Amino Acid Sequence↗
PubMed1990

Failure of the lipid peroxidation inhibitor U74006F to improve neurological outcome after transient forebrain ischemia in the rat.

The lipid peroxidation inhibitor U74006F (21-[4-(2,6-di-1-pyrrolidinyl-4-pyrimidinyl)-1-piperazinyl-16-methylp regna- 1,4,9 (11)-triene-3, 20-dione) was tested for cerebroprotective properties in the rat. Transient forebrain ischemia was induced by occlusion of the carotid arteries and simultaneous lowering of the blood pressure to 40 mmHg. Repetitive doses of 10 mg/kg U74006F were administered intraperitoneally 10 min before and again 30 min and 24 h after the transient forebrain ischemia. U74006F did not significantly improve histological outcome in this model, suggesting lipid peroxidation to be a minor determinant for the neurological outcome under these experimental conditions.

Animals↗
PubMed1990

Postischemic glucose utilization in rat hippocampal layers.

The influence on hippocampal glucose utilization was determined in male Wistar rats 7 days after a 10-min forebrain ischemia. Ischemia was induced by clamping of the carotid arteries and lowering blood pressure to 40 mm Hg. Despite severe neuronal damage as assessed by histological techniques, local cerebral glucose utilization (LCGU) was significantly increased in the pyramidal and radiatum layer of the CA1 sector, while in layers of the CA2, CA3 and CA4 sector and dentate gyrus. LCGU was reduced compared to non-ischemic controls. The increases in LCGU are suggested to reflect long-lasting hyperexcitation in the selectively vulnerable CA1 sector, implicating a correlation between cellular hypermetabolism and neuronal damage.

Animals↗
PubMed1990

Glucose utilization in rat hippocampus after long-term recovery from ischemia.

The influence on hippocampal glucose utilization of a transient 10-min forebrain ischemia was quantified in male Wistar rats after 2 and 3 weeks as well as after 3 months by application of the [14C]2-deoxyglucose technique. Ischemia was induced by occlusion of the carotid arteries and simultaneous lowering of the blood pressure to 40 mm Hg. For identification of the hippocampal architecture, sections were stained for perikarya (cresyl violet) and for acetylcholinesterase. The hippocampal regions clearly showed different responses to the ischemic insult. The necrotic pyramidal cells being almost completely removed, significant increases in glucose utilization occurred in most layers of the CA1 sector at 2 and 3 weeks post ischemia, while widespread reductions prevailed in all other sectors and the dentate gyrus. At 3 months after the ischemic insult, glucose utilization was reduced in all hippocampal structures including the CA1 region. The increases in glucose utilization in the CA1 sector are suggested to indicate long-lasting presynaptic hyperexcitation, while the widespread reductions in glucose utilization demonstrate that neuronal activity is also altered in hippocampal areas that do not show major histological damage.

Animals↗