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Z Frenkel

Publications and source records attributed to Z Frenkel.

14 recordsLinked to original sources
PubMed2006

Molecular-genetic biodiversity in a natural population of the yeast Saccharomyces cerevisiae from "Evolution Canyon": microsatellite polymorphism, ploidy and controversial sexual status.

The yeast S. cerevisiae is a central model organism in eukaryotic cell studies and a major component in many food and biotechnological industrial processes. However, the wide knowledge regarding genetics and molecular biology of S. cerevisiae is based on an extremely narrow range of strains. Studies of natural populations of S. cerevisiae, not associated with human activities or industrial fermentation environments, are very few. We isolated a panel of S. cerevisiae strains from a natural microsite, "Evolution Canyon" at Mount Carmel, Israel, and studied their genomic biodiversity. Analysis of 19 microsatellite loci revealed high allelic diversity and variation in ploidy level across the panel, from diploids to tetraploids, confirmed by flow cytometry. No significant differences were found in the level of microsatellite variation between strains derived from the major localities or microniches, whereas strains of different ploidy showed low similarity in allele content. Maximum genetic diversity was observed among diploids and minimum among triploids. Phylogenetic analysis revealed clonal, rather than sexual, structure of the triploid and tetraploid subpopulations. Viability tests in tetrad analysis also suggest that clonal reproduction may predominate in the polyploid subpopulations.

Alleles↗
PubMed1982

Some aspects of the endocrine status in the inflammatory breast carcinoma (Mastitis carcinosa).

The main endocrine features in a group of 87 patients with inflammatory breast carcinoma with very rapid evolution (group I) and those of 400 patients with breast cancer with no inflammatory signs (group II) have been compared. The mean age at menarche showed a significantly higher degree in group I, where the later menarche was reported in 36.8% of cases (greater than or less than 16 years). The mean number of abortions has been decreased in the same groups. No significant differences regarding to parity, lactation and mean age of the menopause have been found in these two groups. The mean values for total urinary estrogens were significantly higher in group I. The main fractions of 17-ketosteroids were estimated in 60 women of group I and 61 women of group II. The mean levels of these hormones were more decreased in group I, the most significantly differences in these two groups were registered for ethiocholanolone. In the most cases with decreased levels of ethiocholanolone, the survival time was also shorter. Such data showed a more prominent endocrine imbalance in the inflammatory breast carcinoma in comparison with breast cancer patients of normal evolution.

17-Ketosteroids↗
PubMed1978

Levels of principal 17-ketosteroid fractions in urine of breast cancer patients with or without malignant evolutive push.

The main fractions of 17-ketosteroids were estimated in 102 women with breast cancer. Sixty two patients were cases with rapid evolution (malignant evolutive push) or very rapid evolution (inflammatory breast carcinoma). The mean ethiocholanolone levels and partially androsterone levels were significantly decreased in patients with rapid evolution in comparison with the corresponding values found in patients with breast cancer of slow growth.

17-Ketosteroids↗
PubMed1975

Clinical and hormonal aspects in breast cancer with special reference to malignant evolutive push.

It is tried to differentiate between various stages of malignant evolutive push and normal mammary tumors to establish an individual therapeutic procedure. Besides mammography and thermometry, investigations of urinary excretions of estrogenic and androgenic steriods are qualified for this purpose. Patients with malignant evolutive push showed an increased excretion of estrogens which reached its highest levels in patients suffering from inflammatory mammary carcinomas. The excretion of 17-ketosteroids shows a behaviour vice versa. Altogether mammary tumors with malignant evolutive push are characterized by a state of absolute and relative hyperestrogenity respectively. This phenomenon preferably depends on the clinical stage of the disease than on the age of the patients.

17-Ketosteroids↗
PubMed1974

[Hormonal patterns in breast cancers].

Urinary outpout of oestrogens and 17-ketosteroids were estimated in 200 women with breast cancer; 60 of them were cases with rapid evolution (malignant evolutive push). The majority of cases analysed had abnormal hormonal levels, especially of oestrogens. The average oestrogenic levels are higher than the normal values; the highest values correspond to the most severe and rapidly evolutive type of breast cancer, the inflammatory breast carcinoma. In the patients without evolutive push, the proportion of cases with absolute or relative hypooestrogeny is approximately equal toor exceeds the proportion of hyperoestrogenic cases. In the presence of the evolutive push and especially of his most severe type, inflammatory carcinoma, the cases with hyperoestrogeny, both absolute and relative, by hypoandrogeny, are dominant. The proportion of cases with higher 17-ketosteroid urinary outputs than the normal mean is greater in the patients without evolutive push, while in those with evolutive push, the majority of cases have lower values of 17-ketosteroids than the normal mean.

17-Ketosteroids↗
PubMedDate not supplied

Urinary 17-ketosteroid fractions in young patients with breast cancer.

The main fractions of 17-ketosteroids were estimated in 30 young women (under 40 years) with breast cancer and 20 controls of the same age. The determination of the fractionated ketosteroids was made by thin layer chromatography on silicagel. The mean levels of etiocholanolone, androsterone, total ketosteroids and the sum of the fractions of 17-ketosteroids were significantly decreased in patients with breast cancer in comparison with the controls. No significant differences between the mean levels of dehydroepiandrosterone and 11-oxygenated-17-ketosteroids were noted in these groups.

17-Ketosteroids↗
PubMedDate not supplied

Patterns of urinary 17-ketosteroid fractions in hirsutism.

Fractionated 17-ketosteroids were determined in 60 females with hirsutism. The chromatographic method was adapted in the Oncological Institute of Cluj-Napoca. In 32 patients the idiopathic form of hirsutism was confirmed with normal results for all the fractions and only sometimes a slight rise of androsterone. In 18 patients an ovarian origin was affirmed; all of them had androsterone and etiocholanolone over normal limits. In ten patients, who had an adrenal origin of hirsutism the great values of DHEA (dehydroepiandrosterone) were observed. In one patient with virilizing adrenal tumour, both total 17-ketosteroids, and all fractions were much elevated DHEA being over 100 mg/24 hours.

17-Ketosteroids↗