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R Vogt

Publications and source records attributed to R Vogt.

At least 19 recordsLinked to original sources
PubMed1998

Quantitative flow cytometry: inter-laboratory variation.

Quantitative flow cytometry (QFCM) offers a means of standardization within and between flow cytometers. QFCM parameters were set by determining the antibody-binding capacity (ABC) of CD4, CD8, and CD3 cells from 10 normal donors with the use of eight FACScan flow cytometers. QC3 beads and a certified blank bead were used to set up the instruments. Fluorescein isothiocyanate (FITC) conjugated to molecular equivalents of soluble fluorochrome (MESF) microbead standards was used before and after the donor samples were run to ensure that the machines were operating consistently. Lyophilized cells (Cytotrol) were used as a target, to control for antigen expression in the cell preparation. Quantitative Simply Cellular (QSC) beads were used to establish a standard calibration curve for each of the FITC and phycoerythrin antibody conjugates on each of the instruments. Single-parameter fluorescent histograms derived from list-mode files were used to calculate the slope (coefficient of response), intercept (zero channel), number of channels per decade, and ABC or MESF threshold (blank bead). The fluorescence intensity (geometric mean) of the positive and negative donor cell populations was compared with the standard curves, and the ABCs were calculated. The results show consistent instrument performance between laboratories. However, after standardization of CD3, CD4, and CD8 ABCs to microbeads, large variations were noted between donors and laboratories. The source of this variation does not appear to be in the instrumentation but may be due to the lack of an unified set-up protocol, introducing issues of antibody saturation, methods for whole blood lysis and fixation, and the behavior of the microbead standards.

Flow Cytometry↗
PubMed1998

Pantoprazole 20 mg is effective for relief of symptoms and healing of lesions in mild reflux oesophagitis.

AIM: To investigate the efficacy of a low dose of pantoprazole, a gastric proton pump inhibitor, for the relief of symptoms and healing of lesions in mild gastro-oesophageal reflux disease (GERD), and to compare it with the efficacy of ranitidine. METHODS: Patients with endoscopically established GERD (Stage I, Savary-Miller classification) were enrolled into a randomized, double-blind, parallel-group and multicentre study (intention-to-treat n = 209, age range 19-82 years). They were treated once daily with oral pantoprazole 20 mg or ranitidine 300 mg, for up to 8 weeks. End-point parameters included relief of symptoms (heartburn, acid regurgitation, pain on swallowing) and the healing of GERD lesions. Relief from symptoms was assessed after 2 and 4 weeks, and endoscopically confirmed healing of lesions after 4 and 8 weeks. RESULTS: The proportion of patients reporting complete relief from symptoms after 2 weeks was greater in the pantoprazole than in the ranitidine group (69 vs. 48%, P < 0.01), with further improvements seen in the pantoprazole group after 4 weeks (80 vs. 65%, P < 0.05, Cochran-Mantel/Haenszel test). Healing of lesions was confirmed in 70/87 (80%) patients after 4 weeks (pantoprazole group), as compared with 55/86 (64%) patients (ranitidine group) (P < 0.05, per protocol population); after 8 weeks the respective results were 78/87 (90%) and 63/86 (73%) patients (P < 0.01). Both study medications were well tolerated. CONCLUSION: Low-dose pantoprazole (20 mg) is clinically superior to ranitidine (300 mg) in providing fast relief from symptoms and healing of lesions in patients with mild GERD.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1996

Standardizing flow cytometry: construction of a standardized fluorescence calibration plot using matching spectral calibrators.

Calibration of flow cytometers is becoming an increasingly important issue for both quality control of instrument performance and quantitation of antibody binding capacity of cells. Due to the numerous different instruments and analysis software currently available, a standardized method of calibration is necessary if interlaboratory comparison of instrument performance and antibody binding is to be achieved. This report describes a new methodology to obtain a standard calibration plot that can be derived from all instruments and from which specific instrument-independent performance parameters may be calculated that can be used to directly compare the performance and setup of these instruments. The requirements that the calibrated standards must meet are discussed, as well as the acceptable ranges proposed for the instrument-independent performance parameters. In addition, data are presented from standard calibration plots generated by different flow cytometers in numerous laboratories. The corresponding Primary Performance Parameters calculated from these plots are presented and compared. It is expected that the use of this calibration method may help standardize flow cytometric measurements and will provide instrument-independent performance parameters to monitor quality control of instruments and reagents.

Calibration↗
PubMed1996

An N-terminal partial sequence of the 13 kDa Pycnopodia helianthoides sperm chemoattractant 'startrak' possesses sperm-attracting activity.

Freshwater extracts of starfish ovaries were used to purify the sperm-attracting peptide 'startrak' from Pycnopodia helianthoides using hydrophobic interaction chromatography and DEAE-high-pressure liquid chromatography. Partially purified attractant had a molecular mass of 13 kDa, estimated from gel filtration and polyacrylamide gel electrophoresis results. The purified attractant was subjected to amino acid analysis and direct sequencing, and was found to consist largely of a single peptide composed of an estimated 127 residues based on a molecular mass of 13kDa. An N-terminal sequence of amino acids from positions 3 to 34 was obtained and synthesized as: NH2-Ala-Glu-Leu-Gly-Leu-Cys-Ile-Ala-Arg-Val-Arg-Gln-Gln-Asn-Gln-Gly-Gln- Asp-Asp-Val-Ser-Ile-Tyr-Gln-Ala-Ile-Met-Ser-Gln-Cys-Gln-Ser-COOH. The synthetic peptide possessed sperm-attracting activity 130 times greater than the activity of partially purified startrak and showed a pattern of species-specificity of sperm chemotaxis similar to that of startrak. Antibody prepared against synthetic peptide removed the sperm-attracting activity from crude and partially purified preparations of startrak. The partial sequence of startrak was not homologous with that of any of the known echinoid sperm motility-activating peptides.

Amino Acid Sequence↗
PubMed1995

[Rainer Werner Fassbinder's "Garbage, the city and death"-- a German landscape of the soul].

No other recent "art event" has aroused so much public debate in Germany as Fassbinder's play "Garbage, City, Death" (1976). The controversy it sparked on its appearance has still not entirely died down. In a painstaking psychoanalytic interpretation Vogt first shows that the play achieves an artistic representation of the unconscious dilemma besetting the second generation of non-Jewish Germans in their relationship to National Socialism. In Fassbinder's play this dilemma, which is bound up with vicarious guilt feelings, is however only presented and not in any way worked out. The upshot is that all those forms of identification with German traditions that have been repudiated on a conscious level re-enter, as it were by the back door, and attain a new virulence. The author demonstrates that at the heart of the play a mechanism of guilt-refusal is operative that inverts the historical culprit-victim relation and makes the Germans themselves into the real victims. In the second part of his article Vogt is concerned to situate the play and the controversy surrounding it in a broader political context--Bitburg (1985), the "historians' conflict" (1986), Jenninger's speech (1988)--revealing a specific collective psychological inscape in present-day Germany for which, in its profounder well-springs, Fassbinder's play may be legitimately regarded as symptomatic. Fassbinder (born 1945) articulates for his generation aspects of an "ethnic disturbance" (George Devereux) which continues to persist precisely because there is a German past "that refuses to go away" (Ernst Nolte).

Drama↗
PubMed1994

The mycotoxin ochratoxin A deranges pH homeostasis in Madin-Darby canine kidney cells.

Ochratoxin A (OTA) is a nephrotoxin which blocks plasma membrane anion conductance in Madin-Darby canine kidney (MDCK) cells. Added to the culture medium, OTA transforms MDCK cells in a manner similar to exposure to alkaline stress. By means of video-imaging and microelectrode techniques, we investigated whether OTA (1 mumol/liter) affects intracellular pH (pHi), Cl- (Cl-i) or cell volume of MDCK cells acutely exposed to normal (pHnorm = 7.4) and alkaline (pHalk = 7.7) conditions. At pHnorm, OTA increased Cl-i by 2.6 +/- 0.4 mmol/liter (n = 14, P < 0.05) but had no effect on pHi. At pHalk, application of OTA increased Cl-i by 8.6 +/- 2.6 mmol/liter (n = 10, P < 0.05) and raised pHi by 0.11 +/- 0.03 (n = 8, P < 0.05). The Cl-/HCO3- exchange inhibitor DNDS (4,4'-dinitro-stilbene-2,2'-disulfonate; 10 mumol/liter) eliminated the OTA-induced changes of pHi and Cl-i. OTA did not affect cell volume under both pHnorm and pHalk conditions. We conclude that the OTA-induced blockade of plasma membrane anion conductance increases Cl-i without changing cell volume. The driving force of plasma membrane Cl-/HCO3- exchange dissipates, leading to a rise of pHi when cells are exposed to an acute alkaline load. Thus, OTA interferes with pHi and Cl-i homeostasis leading to morphological and functional alterations in MDCK cells.

Animals↗
PubMed1992

CD20 and CD5 expression in B-chronic lymphocytic leukemia.

In order to quantitate a previously noted decrease in CD20 fluorescence intensity (FI) on B-CLL lymphocytes, binding capacities [BC x 10(3) +/- 1SD = number of antibodies bound per cell] were calculated. The mean (N = 5) BC x 10(3) +/- 1SD of CD20 reagents for normal B-PBL and B-CLL lymphocytes confirmed this observation. B-PBL and B-CLL were 56 +/- 11 and 61 +/- 14, and 19 +/- 15 and 18 +/- 16, respectively, for Leu 16 and B1. Although adequate compensation standards for the determination of CD5 and CD20 coexpression are not available, qualitatively, the density of CD5 on both normal B-PBL and B-CLL is less compared to the expression of CD5 by normal T cells. CD5 expression on B-CLL seems to be linked to the lower levels of CD20, whereas CD5 expression may appear to be absent on CLL lymphocytes expressing normal levels of CD20. Levels of CD20 in B-CLL suggest involvement of one or two genes (alleles) whose decreased expression may be linked to CD5 expression.

Antigens, CD↗
PubMed1992

Flow cytometric analysis of whole blood lysis, three anticoagulants, and five cell preparations.

We studied the effects of anticoagulants and cell preparation methods on lymphocyte forward-angle scatter (FSC), autofluorescence, and immunofluorescent staining for CD45, CD14, and CD13. Blood samples collected in ethylenediaminetetracetic acid (EDTA), heparin, and acid citrate dextrose (ACD) were processed by using conventional Hypaque-Ficoll (HF) separation and four whole blood (WB) lysis techniques: Immuno-lyse, Q-Prep, FACS Lyse, and Gen Trak Lysis. Lymphocytes prepared by using three of the four whole blood methods gave FCS values comparable to those isolated by HF, while one method (FACS Lyse) gave consistently lower values. Autofluorescence values were comparable by all methods except Immuno-lyse, which showed consistently higher values in blood stored for 24 h with any anticoagulant. Immunofluorescent values for CD45-stained cells were quite consistent across all methods, and among the whole blood methods, FACS Lyse and Q-Prep uniformly gave the highest purity of CD45-positive cells in the lymphocyte light scatter gates. Additionally, propidium iodide (PI) analyses of CD45-stained whole blood, and analyzed without lysis, confirmed that ACD and heparin were superior to EDTA for maintaining viable leucocytes overnight. Future studies should focus on other commonly used reagents, a wide variety of abnormal samples, and cell viability.

Antigens, CD↗
PubMed1992

Collagel--a new viscoelastic substance for ophthalmic surgery.

A clinical trial comparing the viscoelastic properties of Collagel (human collagen) and Healon (sodium hyaluronate) was performed. Collagel was well tolerated and produced no untoward reaction in the eye. Flare cell measurement was performed during the seven day postoperative period. The initial peak and decline of flare and cell determination showed a similar course in groups treated with Collagel or Healon. A transient increase in intraocular pressure was seen. Endothelial cell loss following surgery was similar in the Collagel and Healon groups. There were no significant differences in intraocular pressure, corneal thickness, endothelial cell density, or visual acuity during the postoperative period. These results suggest that this new viscoelastic substance is comparable to Healon in respect to the parameters described.

Aged↗
PubMed1992

[Current comments on Freud's treatment of "The question of lay analysis"].

The author gives a review on Freud's basic thoughts on lay analysis from 1926 and proceeds with the question why the Deutsche Psychoanalytische Vereinigung (German Psychoanalytic Association) admits only such candidates for psychoanalytic training who are physicians or psychologists. This corresponds with the policies of German health insurance agencies, which include only physicians directly or psychologists indirectly in their plans. He suggests that this attitude derives from a limited view of psychoanalysis, for which he names three different reasons: historical, institutional, and those that grow out of the specifics of psychoanalytic practice.

Freudian Theory↗
PubMed1990

Implantation of posterior chamber lenses in eyes with phakodonesis and lens subluxation.

Unilateral posterior chamber intraocular lens (IOL) implantation was performed after phacoemulsification or extracapsular cataract extraction in ten of 11 patients with phakodonesis or lens subluxation, which was bilateral in two cases. To facilitate placement of the IOL, the anterior capsule was opened with a YAG laser in nine patients. Intraoperative vitrectomy was performed in two patients, and posterior chamber IOL implantation was accomplished with fixation in the ciliary sulcus. Postoperative follow-up studies failed to demonstrate significant decentration or dislocation of the IOLs. Phakodonesis and lens subluxation are no longer considered absolute contraindications to implantation of posterior chamber IOLs.

Aged↗
PubMed1990

["Archaic matrix of the oedipus complex"].

The clinical implication of Janine Chasseguet-Smirgel's concept of the "archaic matrix of the Oedipus complex" is examined, the resulting deeper understanding of the Oedipus myth is considered. A discussion follows of Chasseguet-Smirgel's way of using this concept in her historical evaluation of German Romantism with regard to the Nazi times and nowadays politics of the Westgerman Green Party.

Germany↗
PubMed1986

Experimental endothelial lesions by means of an ultrasound phacoemulsificator.

The current study deals with experimental use of an ultrasound generator for phacoemulsification and its effect on bovine corneal endothelium. The extent of the endothelial defect was defined by staining cell borders and nuclei. Histological examination showed that endothelial cells on the edge of a defect had no nuclei and were partially detached from the Descemet's membrane in some cases. Quantitative determinations of endothelial cell defects demonstrated the effects of distance from the generator (1, 2, and 3 mm) as well as duration of exposure. At 2 and 3 mm, addition of sodium hyaluronate (Healon) to the incubation medium was associated with a statistically significant reduction in size of the endothelial defect.

Animals↗
PubMed1985

A three-state study of waterborne disease surveillance techniques.

For a two-year period, the states of Colorado, Vermont and Washington tested the effectiveness of ten surveillance methods for identifying waterborne disease. Nine were active surveillance methods, soliciting illness reports; one was passive, relying on voluntary disease reporting. One waterborne disease outbreak was identified through use of the nine active methods, while 14 were reported through the passive surveillance method. The presence of coliform bacteria during routine water testing was not related to illness in the community.

Colorado↗