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R Grün

Publications and source records attributed to R Grün.

35 records · Page 2Linked to original sources
PubMed1990

ESR dating evidence for early modern humans at Border Cave in South Africa.

The archaeological and hominid site of Border Cave (KwaZulu, South Africa) has a stratigraphic sequence covering the Middle and Later Stone Ages (MSA and LSA). It has been proposed that four hominid specimens recovered there (BC1 and BC2 of uncertain provenance, and BC3 and BC5 recovered from MSA layers) represent very early examples of anatomically modern humans, supporting an early late-Pleistocene appearance of modern Homo sapiens in Africa. This early appearance, however, has been questioned, largely because of doubts about the stratigraphic positions associated with the specimens and because of the lack of a reliable chronology for the stratigraphic sequence. We now report on the first comprehensive radiometric dating analysis of Border Cave, using electron spin resonance (ESR) on teeth within sediment layers. BC3 is likely to be approximately 70-80 kyr old, and BC5, 50-65 kyr old. BC1 and BC2 are almost certainly less than 90 kyr old. These results, although younger than some age estimates, support the early occurrence of anatomically modern humans at Border Cave. In addition, our results suggest that the Howiesons Poort lithic industry (approximately 45-75 kyr) and the MSA-LSA transition (approximately 35 kyr) are younger than often believed.

Animals↗
PubMed1989

ESR dates for the hominid burial site of Es Skhul in Israel.

The Middle East has been critical to our understanding of recent human evolution ever since the recovery of Neanderthal and early anatomically modern fossils from the caves of Tabun and Skhul (Mount Carmel) over 50 years ago. It was generally believed, on archaeological and morphological grounds, that middle eastern Neanderthals (such as those from Tabun, Amud and Kebara) probably dated from more than 50,000 years ago, whereas the earliest anatomically modern specimens (from Skhul and Qafzeh) probably dated from about 40,000 years. Recent thermoluminescence and electron spin resonance (ESR) determinations, however, have supported biostratigraphy in dating the Qafzeh deposits to an earlier part of the late Pleistocene, probably more than 90,000 years ago. These dates have been questioned on unspecified technical grounds, and it has also been argued that they create explanatory problems by separating the morphologically similar Qafzeh and Skhul samples by some 50,000 years, thus implying a long-term coexistence of early modern humans and Neanderthals in the area. Here we report the first radiometric dating analysis for Skhul, using ESR on bovine teeth from the hominid burial levels. Early uptake and linear uptake ages average 81 +/- 15 and 101 +/- 12 kyr respectively. These analyses suggest that the Skhul and Qafzeh samples are of a similar age and therefore it is possible that the presence of early modern humans in the area was episodic, rather than long-term during the early late Pleistocene.

Animals↗
PubMed1989

[Growth hormone in females with liver cirrhosis].

The median plasma concentration of growth hormone (GH) in 63 women with liver cirrhosis was significantly elevated when compared with a control group (4.4 ng/ml vs 1.8 ng/ml, p less than 0.01). In 38% of the patients GH concentration was higher than 6.0 ng/ml. GH correlated significantly with the degree of decompensation of the cirrhosis (Child A-C). It was not influenced by the concentrations of estradiol, estrone, or testosterone. Thyrotropin releasing hormone (TRH) induced paradoxial GH increase (delta-GH) in 23 patients showed no significant difference to the data of the control group (2.7 ng/ml vs 0.8 ng/ml). The etiology of cirrhosis (alcoholic or non alcoholic) proved to be unimportant concerning the GH elevation. A missing correlation of GH to thyroid stimulating hormone (TSH), and of delta-GH to TRH induced increase of TSH (delta-TSH) argues against the hypothesis that latent hypothyroidism - often described in cirrhosis - might be responsible of the GH elevation.

Adult↗
PubMed1989

[Hyperestrogenemia following various shunt operations: on the role of estrogens in the development of focal nodular hyperplasia of the liver].

Hormones especially estrogens have been suspected to induce liver cell tumours or hepatic focal nodular hyperplasia (FNH). In rats 6 months after portocaval anastomosis (PCA) the occurrence of FNH has been observed. Modified portocaval anastomosis (mPCA) does not lead to FNH. To test the concept of estrogen induced tumour formation we measured in both groups as well as in a shamoperated control group (SOP) the levels of estradiol (E2), estrone (E1) and of testosterone (T). In a further experiment the hormone levels were measured in rats with portocaval transposition (PCT), an operation which leads to high gonadal hormone production. In groups of 6 male rats each (280-300 g) either SOP, PCA, mPCA or PCT were performed. 30 days later the blood levels of E2, E1, and of T were measured by radioimmunoassay. In PCT-rats hormone levels were measured in the blood synchronously taken from the inferior vena cava (prehepatic) and from the heart (posthepatic), to get an information of the hepatic hormone degradation. After PCA the median level of E2 (77 pg/ml) and E1 (63 pg/ml) are significantly elevated when compared with SOP-rats (41 and 43 pg/ml). Equally after mPCA the E2 and E1 levels are significantly higher (61 and 70 pg/ml) than in controls rats. In contrast the concentrations of T are significantly reduced (PCA 0.03, mPCA 0, 10, SOP 1.0 ng/ml). PCA as well as mPCA result in a hyperestrogenic and hypoandrogenic status. When PCA and mPCA are compared, only the testosterone blood levels are significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

[Sex hormones and the hypophyseo-gonadal axis in females with liver cirrhosis in postmenopause].

The hormonal status of men with cirrhosis of the liver has been investigated in numerous studies. Little, however, is known about changes of sexual hormones in women afflicted by this disorder. In a study of 31 postmenopausal women (mean age 63 +/- 8 years) suffering from cirrhosis of various etiology (alcoholic, n = 8; posthepatitic B, n = 1; PBC, n = 5; cryptogenetic, n = 17) the blood levels of estradiol (E2), estrone (E1), androstenedione (A), testosterone (T) and basal and stimulated values of gonadotropins are reported and compared with the data obtained in an age-matched control group (n = 9). In cirrhosis a significant increase of the median E2 (28 vs 12 pg/ml, P less than 0.01) was found, whereas the changes of the blood levels of E1 (88 vs 76 pg/ml), A (63 vs 111 ng/dl), and T (0.30 vs 0.15 ng/ml) did not attain statistical significance in comparison to controls. Within the study group, however, a significant positive correlation with the degree of decompensation of cirrhosis (Childscore A-C) was observed for the steroid hormones measured. Thus, in subgroup C the hormone levels are higher than physiologically expected for postmenopausal women. On the other hand the median FSH (32 vs 48 mU/ml, P less than 0.05) is significantly lower in cirrhosis compared to controls with a trend to decreased values of LH. Very low levels of LH and FSH are found in decompensated cirrhosis. The decrease of LH and FSH can partly be explained by the rise of peripheral hormones (i.e. E2, E1, and in some cases T and A).(ABSTRACT TRUNCATED AT 250 WORDS)

Androstenedione↗
PubMed1985

[Thyroid hormones in women with liver cirrhosis].

Basal thyroid hormone levels were measured in 68 women with liver cirrhosis (LC) of different etiology (alcoholic n = 34, posthepatitic B n = 9, PBC n = 5, cryptogenetic n = 18, M. Wilson n = 2). In addition the rise of TSH after 400 micrograms TRH was measured in 23 women with LC and compared with the data obtained from 17 women of a control group. There was no difference of the median T4-concentrations (LC 8.0 micrograms/dl versus 7.2 micrograms/dl) but a significant correlation of T4 to the grade of decompensation of LC. In contrast of T4 there was a marked decrease of T3 in LC-patients (109 ng/dl versus 143 ng/dl) and a rise of reverse T3 (0.21 ng/ml versus 0.13 ng/ml). The decrease of T3 and rise of reverse T3 equally correlated to the severeness of LC. TBG concentrations fell according to the grade of decompensation of LC and T4/TBG-quotient exhibited no difference to the control data (0.51 both). Though basal thyroid hormones and TSH show euthyroidism the significant augmented TSH release after TRH (delta-TSH 7.0 versus 3.2 microU/ml) indicate a status of latent hypothyroidism. In alcoholic cirrhosis the degree of TSH release was much higher than in non alcoholic cirrhosis. Estradiol and estrone levels correlated significantly negatively to T4, T3, estrone negatively to TBG and positively to reverse T3 but not to TSH and TSH release. Otherwise TSH release correlated positively to estradiol. The thyroid status in women with liver cirrhosis does not differ from the thyroid hormone profile found in men with cirrhosis.

Female↗
PubMed1985

Ultrasound diagnosis of C-cell carcinoma of the thyroid.

Ultrasound screening in 9 and 21 members, respectively, of two families affected by familial C-cell carcinoma, as well as sonographic findings in 6 patients with sporadic medullary carcinoma of the thyroid (MCT), are reported. Unilateral and bilateral tumor nodules were identified by sonography in 12 of a total of 13 patients with MCT (n = 9) or local tumor recurrence following thyroidectomy (n = 4); one carcinoma, 3 X 6 mm in diameter, was missed. Nine of the 12 (75%) were clinically occult, nonpalpable C-cell carcinomas. The smallest occult MCT correctly diagnosed by ultrasound had a diameter of 4 mm. A positive correlation was found between the sonographically determined tumor mass (number/size of nodules/metastases) and the plasma calcitonin level. Pheochromocytomas were diagnosed by ultrasound as part of a multiple endocrine neoplasia (MEN IIa) in two patients with MCT. The echomorphologic findings of the intrathyroid C-cell carcinomas and their metastases display characteristic but nonspecific features. Sonographic findings on these tumors should therefore not be interpreted without consideration of plasma calcitonin assays.

Adolescent↗
PubMed1985

[High resolution real time sonography of parathyroid tumors].

A total of 15 patients with parathyroid tumours were scanned preoperatively using high-resolution real-time sonography (7 MHz). Of these, 14 had a single adenoma or primary hyperplasia, one had a carcinoma. In 13 out of 15 patients the echogenicity of the parathyroid tumours was consistently less than of the adjacent normal thyroid tissue; in 2 out of 15 cases parathyroid neoplasms were barely distinguishable in echogenicity from thyroid tissue. No specific echomorphologic differences were proved to exist between primary parathyroid hyperplasia, adenoma or carcinoma. The smallest parathyroid neoplasia in this study detected by sonography measured 5 x 8 mm in diameter. The value and limits of parathyroid sonography were discussed with regard to our own experience and the reports in the literature.

Adenoma↗
PubMed1985

[Prolactin in females with liver cirrhosis].

The median plasma level of prolactin in 94 women with cirrhosis of the liver did not differ significantly when compared with a control group (8,0 versus 7,2 ng/ml). Nevertheless 22% of the investigated women exhibited a plasma prolactin level higher than 15 ng/ml. The prolactin concentrations correlated to the severeness of cirrhosis and in the subgroup with decompensated cirrhosis the prolactin concentrations were found to be significantly elevated (12 ng/ml). Like basal prolactin the TRH-induced prolactin release showed no significant difference between cirrhotic women and controls (36,1 versus 38,5 ng/ml). No difference could be observed between the prolactin concentrations of alcoholic or non alcoholic cirrhotic women, and prolactin did not correlate with estradiol or estrone plasma levels. Other factors than cirrhosis itself (i.e. medical treatment, renal insufficiency, stress) must be discussed as causing hyperprolactinemia in cirrhosis.

Female↗
PubMed1984

[Sex hormones and fertility following portacaval anastomosis in rats].

Portocaval anastomosis (PCA) in the normal male rat causes profound alterations in testicular morphology and function and in plasma levels of sex steroids as well as of gonadotropins. Testicular atrophy is accompanied by a significant decrease of plasma testosterone (0.03 ng/ml versus 0.99 ng/ml) and an increase of estradiol (76.2 pg/ml versus 39.7 pg/ml) and estrone (68. pg/ml versus 45.5 pg/ml). Plasma levels of gonadotropins (LH, FSH) and prolactin are lowered too (LH: 15 ng/ml versus 28.5 ng/ml, FSH:119 versus 182 ng/ml, prolactin:53 versus 109 ng/ml). The altered sex hormone metabolism is reflected in marked changes of the morphology and nucleic acid content of the metabolizing organs i.e. liver, gonades and kidney. The results of this study are consistent with the hypothesis that portosystemic shunt per se plays an important role in the pathogenesis of the disturbed metabolism of sex hormones observed in patients with liver cirrhosis and portal hypertension.

Adrenal Glands↗
PubMed1982

Demonstration of circulating autoantibodies against the plasma membrane of isolated thyroid cells in Graves' disease.

Antibodies against the plasma membrane of isolated human and porcine thyroid cells were demonstrable by a linear fluorescence pattern in sera from 29 out of 37 patients with Graves' disease. In 3 cases the antibodies reacted only with human thyroid cells. In a group of patients with Hashimoto's thyroiditis, 6 of 8 sera reacted with human thyroid cells in a granular fluorescence pattern. With one exception, sera from patients with non-toxic goiter showed no binding of IgG to thyroid cells. Sera from healthy controls were negative in this test system. There was no correlation between the presence of antibodies against thyroid cells and antibodies against thyroglobulin. Antibodies against thyroid microsomal antigens were found in 80% of patients with circulating thyroid cell membrane antibodies; 5 sera with membrane antibodies were negative for microsomal antibodies. Twenty sera of patients with Graves' disease were tested by passive haemagglutination test against peak I and peak II of the human thyroid fractionation with Sephadex G100. Antibodies against peak I were found in 14 sera and against peak II in all 20 sera. The data indicate that the antibodies in sera from patients with Graves' disease are directed mainly against a species-unspecific antigen of the plasma membrane from thyroid cells with a probable molecular weight between 4-7 S and are unrelated to thyroglobulin.

Animals↗
PubMed1981

Peptide hormones in liver cirrhosis and hepatocellular carcinoma.

Immunoreactive serum levels of human chorionic gonadotrophin (HCG), its alpha- and beta- subunits (alpha-HCG and beta-HCG), calcitonin (CT), parathyroid hormone (PTH), prolactin (PRL), adrenocorticotropic hormone (ACTH), and growth hormone (GH) were increased in 8 to 68% of 44 patients with hepatocellular carcinoma. With the exception of two patients, ACTH and PRL levels were only moderately increased, while alpha-HCG, GH, ACTH and PRL levels were not significantly different from the levels found in cirrhosis suggesting that metabolic effects due to impaired liver function may be responsible for their increase in liver cirrhosis and primary liver cell carcinoma. In contrast, HCG, beta-HCG, CT and PTH were associated with a higher incidence of elevated immunoreactive hormone levels than the other peptide hormones; higher concentrations were noted in tumor patients than with liver cirrhosis alone. Therefore, we suggest that metabolic effects due to cirrhosis may influence the serum levels and be more important than ectopic secretion by hepatocellular carcinoma.

Adrenocorticotropic Hormone↗