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R Chatelain

Publications and source records attributed to R Chatelain.

At least 37 records · Page 2Linked to original sources
PubMed1989

Representativity and reproducibility of DNA malignancy grading in different carcinomas.

The reproducibility of the determination of the "DNA malignancy grade" (DNA-MG) was tested in 56 carcinomas of the colon, breast and lung while its representativity was tested on 195 slides from 65 tumors of the colon, breast and lung. DNA measurements were performed on Feulgen-stained smears with the TAS Plus TV-based image analysis system combined with an automated microscope. The variance of the DNA values of tumor cells around the 2c peak, the "2c deviation index" (2cDI), was taken as a basis for the computation of the DNA-MG, which ranges on a continuous scale from 0.01 to 3.00. The representativity, analyzed by comparison of the DNA-MGs measured in three different areas of the same tumor greater than or equal to 1.5 cm apart from each other, yielded an 81% agreement. No significant differences between DNA-MGs of these areas were found. The intraobserver and interobserver reproducibilities of the DNA grading system, investigated by repeated DNA measurements, were 83.9% and 82.2%, respectively. In comparison, histopathologic grading of the 27 breast cancers studied yielded 65% intraobserver and 57% interobserver reproducibilities and 66% representativity.

Breast Neoplasms↗
PubMed1989

Diagnostic and prognostic value of DNA cytometry in gynecologic cytology.

A survey of the diagnostic and prognostic value of DNA cytometric measurements in gynecologic tumors is given. In slight-to-moderate epithelial dysplasias of the uterine cervix, morphologic studies alone cannot make a definite distinction between benignity and malignancy, nor can they identify all precancerous lesions. DNA cytometry may help in these cases to detect prospective malignancy. Cytologic and histologic grading of malignancy often does not provide correct information about the prospective behavior of an individual tumor; its reliability is hampered by low interobserver reproducibilities. DNA cytometry may supplement subjective morphologic grading by providing objective and reproducible prognostic indices. The advantages and disadvantages of TV-based image cytometry and flow cytometry for application in routine gynecologic pathology and the different attempts at diagnostic DNA interpretation are discussed.

Breast Neoplasms↗
PubMed1989

DNA grading of malignancy in breast cancer. Prognostic validity, reproducibility and comparison with other classifications.

The prognostic significance of the "DNA malignancy grade" (DNA-MG) was tested in a series of 104 breast cancer patients in comparison with TNM staging, histomorphologic grading according to Bloom and Richardson, mean nuclear area (MNA) and DNA-histogram classification according to Auer. The reproducibility and representativity of the grading systems were investigated, and their results in primary tumors and lymph node metastases were compared. The scalar DNA-MG was assessed on monolayer smears prepared from paraffin-embedded tissues; the smears were automatically Feulgen stained and used for rapid interactive DNA cytometric evaluation by an automated microscope and a TV image-analysis system. TNM staging showed the highest correlation with survival, followed by histomorphologic grading and DNA-MG; MNA and the DNA-histogram classification failed to give statistically significant prognostic information. Both histomorphologic grading and DNA-MG were identified as parameters adding independent prognostic information to the TNM staging. However, only DNA-MG demonstrated an acceptable reliability, with small 95% ranges between repeated measurements within the primary tumor (+/- 0.3 DNA-MG) and a strong correlation between the results in the primary tumor and its lymph node metastases. These findings show that the DNA-MG is a valid and reliable prognostic index that adds significant prognostic information to TNM staging.

Aged↗
PubMed1989

Diagnosis of prospective malignancy in koilocytic dysplasias of the cervix with DNA cytometry.

DNA cytometric measurements were performed with a TV image analysis system on 90 routine cytologic cervical smears from 18 women after automatic restaining of the smears with the Feulgen method. In the cytologic follow-up all the patients revealed borderline lesions (mild to moderate dysplasia) of the epithelium with koilocytosis. Since DNA aneuploidy is widely accepted as a marker for malignancy, an attempt was made to obtain a DNA diagnosis of prospective malignancy in these cases on the basis of the detection of single aneuploid cells. Because koilocytosis strongly suggests human papillomavirus infection, euploid polyploidy might result in up to 8c (c = haploid amount of DNA). Therefore, the aneuploidy detection threshold was set to 9c, excluding values around 16c and 32c (+/- 12.5%) to avoid false-positive diagnoses in cases of higher polyploidy values. The DNA diagnosis of malignancy was made in 13 patients. In 12 of them, carcinoma in situ was diagnosed in the histologic follow-up, resulting in 100% sensitivity of the DNA diagnosis. In five patients no cells greater than 9c were measured, leading to a benign DNA diagnosis. In the histologic follow-up, six patients revealed normal epithelium or moderate dysplasia. Thus, the specificity of the DNA diagnosis was 83.3%.

Adult↗
PubMed1984

Effects of continuous infusions of 4-hydroxyoestradiol and oestradiol on plasma LH-levels in the ovariectomized ewe.

Ovariectomized ewes were infused over a period of 12 h at constant rates with different doses of the catecholoestrogen 4-hydroxyoestradiol (4-OHE2) or the primary oestrogen oestradiol (E2) via a catheter placed in the right atrium. Blood samples were drawn every hour for a total period of 48 h starting 1 h before the beginning of the steroid infusion. Luteinizing hormone (LH), 4-OHE2 and E2 concentrations were measured in these samples by specific radioimmunoassays. Infusions of low doses E2 (0.5 microgram/h) or 4-OHE2 (2 micrograms/h) caused only a suppression of LH-secretion. At doses of 1 microgram E2/h or 5 micrograms 4-OHE2/h this negative effect was followed by inconsistent elevations of plasma LH. Beyond this threshold dose, E2 at infusion rates of 2, 5 and 10 micrograms/h and 4-OHE2 at infusion rates of 10, 25 and 50 micrograms/h produced the negative effect and massive LH-surges. At still higher infusion rates (E2: 20 micrograms/h, 4-OHE2: 100 micrograms/h) lower elevations of plasma LH levels were observed. 4-OHE2 had to be infused at 4-5 times higher rates than E2 to obtain comparable plasma concentrations of either oestrogen. Under this condition the effects of 4-OHE2 and E2 were similar indicating that 4-OHE2 has the same potency as E2 at central target sites.

Animals↗
PubMed1981

[Phenotype characteristics of 100 strains of Pseudomonas cepacia. Proposition of a biovars classification (author's transl)].

The authors compared the phenotype characteristics of 100 strains of Pseudomonas cepacia mostly of hospital origin to those of the typical mother strain (ATCC 25416). The morphological, cultural and biochemical characteristics (oxidase characteristics, ONPG, LDC, gelatinase and esculine were generally positive), nutritional characteristics (use of numerous organic compounds) and the antibiotypes (usually resistant to betalactamines, aminosides, polymyxins, tetracycline and furans) are reported, together with the differential diagnostic problems between P. cepacia and P. maltophilia (TTR+ methionine requirement). P. pseudomallei (LDC-, ODC-, ADH+, ONPG-) and Agrobacterium sp (urease+, LDC-, ODC-, absence of exoenzymes and use of citrate and malonate). An original classification in 8 biovars (characteristics used : esculine, nitratase, ONPG) permitted epidemiological marking of the strains and a study of their distribution.

Humans↗
PubMed1979

[Septic arthritis due to a nontoxigenic diphtheria bacillus].

Septic arthritis of the hip in a 2 year old child is described. A nontoxigenic diphtheria bacillus was isolated in large numbers from the articular fluid. The same organism was isolated from excoriated skin lesions of the toes. The bacteriology, epidemiology and pathology of the infection are discussed.

Arthritis, Infectious↗
PubMed1975

[Isolation of "Brucella suis" biotype 5 from a bitch, in Madagascar. Validity of the species name "Brucella canis" (author's transl)].

A Gram-negative organism isolated from a btich, in Madagascar, was examined by bacteriologic, immunologic and metabolic methods, in parallel with cultures representative of the Brucella species. The organism fits well into the genus Brucella on the basis of its growth, biochemical and antigenic characteristics and was found to have the metabolic pattern on L-asparagine (-), L-arginine (+) and DL-ornithine (+) that identifies and defines the species Brucella suis. It is of rough colonial morphology and electron microscopy showed a cell wall structure similar to that of other rough Brucella. By all the other recommended criteria for btotype identification it was found to be similar to Brucella suis biotype 5 best known as Brucella canis. In contrast to the strains of this biotype, it grows on basic fuchsin at 20 mug/ml and on safranine O at 200 mug/ml. These differences obtained with just one strain would not justify by now the proposal for a new biotype. We favor the designation Brucella suis biotype 5 proposed by Meyer, and the validity of Brucella canis (Carmichael and Bruner) as a separate species is discussed. It is the first strain of Brucella isolated in Madagascar.

Abortion, Induced↗