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Biomedical subjects

R Petersen

Publications and source records attributed to R Petersen.

At least 91 records · Page 5Linked to original sources
PubMed1983

Low incidence of deletion of the esterase D locus in retinoblastoma patients.

Esterase D was quantitatively measured in the red blood cells from three patients from three separate kindreds who had abnormalities of chromosome 13. The esterase D activity was proportional to the number of copies of the q14 region of chromosome 13 present. These findings confirm published data localizing the esterase D gene to chromosome band 13q14, a region which is important in the etiology of retinoblastoma. Fifty-one additional retinoblastoma patients not known to have any chromosomal defect also underwent esterase D determination. In none of these patients did the esterase D measurement detect a 13q14 deletion. The normal esterase D levels in this series of 51 retinoblastoma patients suggest that deletion of an esterase D locus is infrequent in retinoblastoma patients. It must be noted that patients who are mosaics, with a 13q14 deletion in only a fraction of all somatic cells, could possibly have normal red blood cell esterase D levels. Further study is necessary to determine if esterase D determination of all retinoblastoma patients is a worthwhile clinical tool.

Adolescent↗
PubMed1980

A morphologic study of the influx of neutrophils into dog lung alveoli after lavage with sterile saline.

The appearance of neutrophils in the alveoli of the lung is a common result of pulmonary infection, although the route of neutrophil migration across the alveolar wall has not been demonstrated in normal animals. Recently, however, several methods of stimulating the influx of neutrophils into alveoli have been developed. In the present study, the lung wash model was used to attract large numbers of neutrophils into the airways in order to identify the site of influx of alveolar neutrophils. The combined use of scanning and transmission electron microscopy has made it possible to visualize the migration of neutrophils from the capillaries, through the interstitial spaces, and through the epithelium at the junctions between Type I and Type II cells.

Animals↗
PubMed1979

Size of the pool of alveolar neutrophils in normal rabbit lungs.

Morphometric methods and two unique characteristics of neutrophils enabled us to measure the size of the pool of neutrophils in alveoli of rabbit lungs. Rabbit lungs contained an estimated 6.11 x 10(4) alveolar neutrophils/g wet wt of lungs, and 9.57 x 10(5) alveolar neutrophils/rabbit. Lung lavage was successful in removing an average of 42.2% of the neutrophils in the air containing spaces of the lungs. An average of 2.5 +/- 3.5 (SD)% of the cells in the lung washes were neutrophils, but an average of 10.23 +/- 5.0 (SD)% of the cells that were free in the alveolus were neutrophils. Studies of the interaction of alveolar macrophages and neutrophils in vitro showed that neither cell phagocytoses or destroys the other in significant quantities; however, alveolar macrophages containing neutrophils have been observed.

Animals↗
PubMed1977

[Synthesis and characterization of some cardenolide glucuronides and sulphates (author's transl)].

Cardenolide glucuronides are synthesized in the following way: firstly cardenolide glucosides are prepared by the reaction with acetobromglucose; secondly the hydroxymethyl group of the glucose moiety is oxydized in presence of a platinum catalyst to the carboxyl group of the final glucuronic acid. Glucuronides of the following cardenolides are prepared and described: digoxin, digoxigenin, digitoxin, digitoxigenin-monodigitoxoside, digitoxigenin, and 3-epi-digitoxigenin. Sulphates of digoxigenin, digitoxigenin, and 3-epi-digitoxigenin are prepared by direct reaction of these cardenolides with chlorosulphonic acid in pyridine. The assumed structure of some conjugates has been confirmed by n.m.r. spectroscopy. A high water solubility (6.7-65.1 g/l), a minute chloroform solubility (0.0002-0.0005 g/l), and a low octanol/polar nature of these compounds. Inotropic or toxic cardiac activities of the conjugates are examined on isolated guinea pig papillary muscles and by the Hatcher method on cats. Conjugates with at least one digitoxose show cardioactivities comparable to digoxin or digitoxin. In contrast to that the conjugated genins indicate decreased activities which are at least one-tenth of the potency of the unconjugated glycosides.

Animals↗
PubMed1977

[Affinity of polar digoxin and digitoxin metabolites for digoxin and digitoxin antibodies].

The affinities of some polar and non-polar digoxin and digitoxin metabolites to the related antibodies are largely dependent on the structure of their genin parts. Metabolites with unchanged genins show high cross reactivities towards their related antibodies when compared to the original immunogenic cardenolides. Towards the digoxin antibody the following cross reactivities were found: digoxin-16'-glucuronide 50%, digoxigenin 89.5%, and digoxigenin-3-glucuronide 85%. Values of the same order of magnitude were found with the corresponding digitoxin metabolites and the digitoxin antibody. In contrast, there is a marked decrease in cross reactivity caused by only minor changes in the genin part. With the digitoxin antibody the following cross reactivities are found: digoxin (i.e. 12-OH-digitoxin) 9.1%, 3-epi-digitoxigenin 5.6% and 3-epi-digitoxigenin-3-sulphate 1%. Bcause 12-hydroxylation has been reported to be one of several possible ways of digitoxin metabolisation in man, from a theoretical point of view erroneous results in the clinical digitoxin estimation by radioimmuno-assay are possible. In the case of all of the other metabolites the alterations in positive inotropic activity and cross reactivity run largely parallel.

Antibody Specificity↗
PubMed1975

Retinblastoma: a modification in radiation therapy technique.

Patients with retinoblastoma treated with a single lateral field often suffer multiple recurrences in the anterior portion of the retina. The authors believe that these marginal recurrences are related to dose heterogeneity and that the entire retinal surface is at risk. In an attempt to treat the entire retinal surface and still protect the lens and anterior chamber, a conventional lateral field with the anterior beam edge at the equator of the globe is used with a second anterior field in which the central divergent lens block is hung in a pendulum fashion along the central axis. The shadow of the central block projects a diameter of 10 mm at the anterior corneal surface which well encompasses the lens. The fields are weighted 1:4.5 (anterior to lateral).

Female↗
PubMed1975

Back pain and isometric back muscle strength of workers in a Danish factory.

105 factory workers (38 females and 67 males) have been questioned about their frequency of back pain. 60% of the females and 61% of the males have previously experienced episodes of back pain. 21% of the females and 37% of the males have been absent from work due to back pain. The incidence of back pain is not related to age, height, sort of work, or isometric muscle strength of the back (IS). For the males the incidence rises with increasing weight, i.e. combination of height and obesity, but is not related to any two single factors. For the females there is no correlation between the incidence of pain and weight. IS is correlated to height and age in the males but not in the females. Standards for IS are presented and suggested as a guide to evaluation of the working capabilities of individual subjects with back pain.

Adult↗