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Biomedical subjects

S Konopka

Publications and source records attributed to S Konopka.

At least 19 recordsLinked to original sources
PubMed2001

Qualitative and quantitative assessment of intratubular dentin formation in human natural carious lesions.

It was the aim of this study to investigate the scanning electron microscopy (SEM) features and the element content of calcium (Ca) phosphorus (P), magnesium (Mg), oxygen (O), and carbon (C) of sound dentin, demineralized dentin, secondary dentin, intratubular and peritubular de novo dentin formation due to caries progression and to compare the element content with chemically pure hydroxyapatite. Eighteen extracted teeth with deep dentin carious lesions were embedded in Technovit 9100 (Kulzer), and serial sections of 80 microm thickness were made. These sections were then investigated with polarized light microscopy to identify the lesions. Two sections of each lesion were then coated with carbon and studied with a scanning electron microscope. Of the 18 teeth, 8 showed intratubular dentin formation. The element content was measured using energy dispersive X-ray analysis (EDX). About 75% of all involved dentin tubules showed intratubular de novo dentin formation. The Ca/P ratio in sound dentin, demineralized dentin, peritubular dentin, and secondary dentin was within the range of hydroxyapatite, whereas in intratubular dentin the Ca/P ratio was different than that of hydroxyapatite. The element content for Ca was statistically highly significantly different (P < 0.01) among sound dentin/intratubular dentin, sound dentin/peritubular dentin, and sound dentin/ secondary dentin, but not between sound dentin/ demineralized dentin and sound dentin/hydroxyapatite. For the other measured elements varying statistical differences were found. Our results indicate that intratubular dentin does not occlude the dentin tubules completely and mineralizes different than that of sound dentin and may therefore not be true hydroxyapatite.

Dental Caries↗
PubMed1997

Imaging of pelvic postpartum complications.

Differentiation between endometritis and RPOC in febrile postpartum patients is commonly requested by clinicians. Sonography is the screening technique of choice to assess the endometrial contents. For cases in which the retained placenta is calcified or still has demonstrable blood flow, a specific diagnosis of RPOC can be made. In more complicated cases, a CT scan or an MR image may be requested. In addition to evaluating the uterus and any intra- or extrauterine fluid collections, attention must be paid to the ovarian veins to exclude the diagnosis of ovarian vein thrombosis.

Adult↗
PubMed1988

Salivary caffeine and neonatal behavior: assay modification and functional significance.

A radioimmunoassay (RIA) was developed for the quantification of caffeine in saliva. The mean salivary caffeine level for this sample of 40 full-term, AGA, healthy 1-2 day old human neonates was consistent with levels reported in previous studies. Salivary caffeine was significantly correlated with the number of state changes and startles observed during administration of the Brazelton Neonatal Behavior Assessment Scale. There was also a nonsignificant trend correlating salivary caffeine with visual orienting and consolability.

Behavior↗
PubMed1986

[Not Available].

Explore the source record for details and available documents.

Historiography↗
PubMed1981

Intrinsic factor, free of R proteins, can be prepared from mouse stomach and used in a ligand assay specific for "true" cobalamin.

A ligand assay specific for cobalamin that uses mouse stomach as the source of intrinsic factor has been developed. When mouse stomach extract incubated with radiocobalamin is fractionated by gel chromatography, the radioactive complex elutes as a single peak with apparent molecular weight of 54,900. Formation of the complex is greater than 98% inhibited by human anti-intrinsic factor antibody. When the equivalent of 10,000 pg/ml of cobinamide is added to serum, the apparent cobalamin concentration detected averages 8.5 pg/ml. Correlation with the Lactobacillus leichmannii microbiologic assay results in the regression equation y = 0.97x + 20. In six patients who had megaloblastic anemia the serum cobalamin by the mouse intrinsic factor ligand assay ranged from 0 to 9 pg/ml. Because the primary source of intrinsic factor is free of R proteins, there is no need for extensive purification of the extract. The assay is sensitive, precise, and accurate, and no more difficult to perform than other conventional ligand assay procedures.

Anemia, Megaloblastic↗
PubMed1977

Proficiency testing for the radioimmunoassay of carcinoembryonic antigen. A one-year report.

Forty-three laboratories participated in an interlaboratory testing program offered by the College of American Pathologists for the radioimmunoassay (RIA) of carcinoembryonic antigen (CEA). Thirty correctly reported a sample with 1.9 ng of endogenous CEA per ml as less than 2.5 ng. For samples with added exogenous CEA at the 5.4 ng/ml level, 24 laboratories reported too low and six too high (more than 2 SD beyond the targe value). At the 8.9 ng/ml concentration, three laboratories underestimated the CEA, while 18 overestimated the sample's concentration. A similar proportion of the laboratories performed in the same manner when estimating CEA at a target concentration of 15.9 ng/ml (five underestimating and 27 overestimating the concentration). Although individual variations were large, the majority of participating laboratories can reliably distinguish normal concentrations of CEA from moderate, intermediate and large elevations.

Carcinoembryonic Antigen↗