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Biomedical subjects

H Sommer

Publications and source records attributed to H Sommer.

At least 55 records · Page 3Linked to original sources
PubMed1997

Comparison of technetium-99m-sestamibi scintimammography with contrast-enhanced MRI for diagnosis of breast lesions.

UNLABELLED: Scintimammography using 99mTc-sestamibi and contrast-enhanced MRI were performed to determine the diagnostic accuracy of either method in the diagnostic workup of patients suspicious for breast tumors. METHODS: Fifty-six patients (42 with indeterminate mammograms) underwent preoperative prone planar scintimammography and pre- and postcontrast-enhanced MRI. Visually determined signal increase after application of Gd-DTPA was compared with visually scored sestamibi uptake, and the diagnoses of both methods were correlated with the final histopathologic results. RESULTS: Overall, sensitivity and specificity of scintimammography for diagnosing breast cancer were 88% and 83%, respectively. In the subgroup of patients with indeterminate mammograms, sensitivity was 79% and specificity was 83%. MRI readings provided a higher sensitivity (91% with respect to all patients and 89% with respect to patients with indeterminate mammograms), but a considerably lower specificity (52% in both groups) due to contrast-enhancement in different benign lesions. CONCLUSION: Due to its considerably higher specificity, scintimammography rather than MRI may be suitable to reduce the number of breast biopsies which yield benign results. Thus, this method may be suggested as the preferable tool in the diagnostic workup of patients with indeterminate mammographic findings.

Adult↗
PubMed1997

Evaluation of mammographic breast lesions with Tc-99m sestamibi scintimammography and contrast enhanced MRI.

Scintimammography using Tc-99m sestamibi and contrast enhanced MRI were performed in order to determine the accuracy of both methods in the diagnostic work up of patients with suspicious or indeterminate preliminary diagnosis. 25 controls and 56 patients (14 with suspicious and 42 with indeterminate preliminary diagnoses), in whom physical examination and/or mammography warranted breast biopsy, underwent prone planar scintimammography. Sestamibi uptake was scored visually and measured using the ROI technique to enable semiquantitative evaluation. The patient group additionally underwent plain and contrast enhanced MRI. Visually determined signal increase following application of Gd-DTPA was compared with scintigraphic findings and final histopathologic results. Sensitivity and specificity of semiquantitative scintimammography for diagnosing breast cancer was 88% and 87%, respectively. Based on ROC analysis a target/non target ratio R > 1.3 was shown to be the optimal threshold for separating benign from suspicious scintigraphic diagnoses. MRI reading provided a slightly higher sensitivity (91%), but a considerable lower specificity (52%) due to contrast enhancement of different benign lesions. In the clinically important patient subpopulation with indeterminate results from previous diagnostic procedures, sensitivity of scintimammography fell to 79%, while specificity remained at 87%. MRI revealed a higher sensitivity of 89% and a lower specificity of 52%. Our data indicate that semiquantitative scintimammography using Tc-99m sestamibi provides a comparable sensitivity to contrast enhanced MRI in the assessment of breast cancer. The latter does not reduce the number of biopsies yielding benign results due to the high number of false positive diagnoses. Therefore, scintimammography seems to be the preferable tool in the diagnostic work-up of patients with indeterminate mammographic diagnoses.

Aged↗
PubMed1997

[Quality of life after gynecologic tumors in causal attribution to clinico-somatic findings].

The bio-psycho-social model was used in the presented study to observe the course of chronic diseases. An attempt was undertaken to correlate the psychosocial situation of 165 women with no presence of disease following breast cancer or genital cancer with their present organic status. The open discussion, a half standardized interview and the gynecological-oncological physical examination were implemented using predetermined parameters. The results of the general well-being scores from the interview and the results of organic status for all 165 patients were related using a rank-correlation between the objective and subjective score. A discrepancy between the psychosocial situation and the objective physical finding was found in the majority of women. The goal of the treatment of chronically ill patients especially following oncological tumors should thus have equal emphasis on the psychosocial and organic dimensions of the disease.

Adaptation, Psychological↗
PubMed1996

Multiple interactions amongst floral homeotic MADS box proteins.

Most known floral homeotic genes belong to the MADS box family and their products act in combination to specify floral organ identity by an unknown mechanism. We have used a yeast two-hybrid system to investigate the network of interactions between the Antirrhinum organ identity gene products. Selective heterodimerization is observed between MADS box factors. Exclusive interactions are detected between two factors, DEFICIENS (DEF) and GLOBOSA (GLO), previously known to heterodimerize and control development of petals and stamens. In contrast, a third factor, PLENA (PLE), which is required for reproductive organ development, can interact with the products of MADS box genes expressed at early, intermediate and late stages. We also demonstrate that heterodimerization of DEF and GLO requires the K box, a domain not found in non-plant MADS box factors, indicating that the plant MADS box factors may have different criteria for interaction. The association of PLENA and the temporally intermediate MADS box factors suggests that part of their function in mediating between the meristem and organ identity genes is accomplished through direct interaction. These data reveal an unexpectedly complex network of interactions between the factors controlling flower development and have implications for the determination of organ identity.

Amino Acid Sequence↗
PubMed1996

Alteration of tobacco floral organ identity by expression of combinations of Antirrhinum MADS-box genes.

Floral organ identity is largely controlled by the spatially restricted expression of several MADS-box genes. In Antirrhinum majus these organ identity genes include DEF, GLO and PLE. Single and double mutant analyses indicated that the type of organ found in a particular whorl is dependent on which combination of these genes is expressed there. This paper reports the ectopic expression of Antirrhinum organ identity genes, alone and in combinations, in transgenic tobacco. Although the phenotypes are broadly in agreement with the genetic predictions, several unexpected features are observed which provide information concerning the action of the organ identity genes. The presumed tobacco homologue of DEF, NTDEF, has been isolated and used to investigate the influence of ectopic expression of the Antirrhinum organ identity genes on the endogenous tobacco genes. Analysis of the spatial and temporal expression patterns of NTDEF and NTGLO reveals that the boundaries are not coincident and that differences exist in the regulatory mechanisms of the two genes concerning both induction and maintenance of gene expression. Evidence is provided which indicates that organ development is sensitive to the relative levels of organ identity gene expression. Expression of the organ identity genes outside the flower or inflorescence produced no effects, suggesting that additional factors are required to mediate their activity. These results demonstrate that heterologous genes can be used to predictably influence floral organ identity but also reveal the existence of unsuspected control mechanisms.

Amino Acid Sequence↗
PubMed1995

[Significance for prognosis of delayed diagnosis and treatment of breast cancer].

In a study of 7608 patients with primary breast cancer the effect of patient's and doctor's delay on survival was examined. The delay was arbitrarily divided into the following intervals: Short (0-14 days), intermediate (15-60 days) and long (> 60 days). The delay had significant influence on survival. A long patient's delay was associated with an unfavourable outcome, as compared with a short delay. On the contrary, the prognosis was better for patients with a long doctor's delay compared to that of a short doctor's delay. Overall, when corrected for age, the prognostic value of delay in terms of mortality increased by 24% for a long patient's delay compared to a short one, and by 13% for a short doctor's delay compared to a long one. This suggests that all causes of delay should be kept at a minimum.

Adult↗
PubMed1995

Determination of lactate dehydrogenase activity and urea content in milk by dry chemistry.

Comparison of the new technique of dry chemistry (EKTACHEM 700-XR, Eastman Kodak Co., USA) with conventional wet chemistry (HITACHI 717, Boehringer Mannheim, Germany) for quantitations of lactate dehydrogenase activity and urea content in bovine milk resulted in correlation coefficients of more than 0.9 even when measuring fresh raw milk by dry chemistry.

Animals↗
PubMed1994

[Follow-up and social consequences of Crohn disease and ulcerative colitis].

PATIENTS: We studied the course and particularly the social consequences of Crohn's disease (n = 107) and ulcerative colitis extending beyond the sigmoid colon (n = 22) during the first 6.1 respectively 6.3 years after onset. RESULTS: Under common treatment, the disease activity decreased and the body mass index increased significantly in the majority of patients, but about 30% of them reached no continuous remission. The professional training was delayed in 23% of patients with Crohn's disease and 9% of those with ulcerative colitis. However, by objective datas and in the patients' own opinion the effect of both diseases on the professional qualification and occupational status which were reached in the end was small. The percentage of partly occupied patients and those without work compared to that of healthy ones. 11% of patients with Crohn's disease and 14% with ulcerative colitis had to retire prematurely. The patients' family status and the number of their children matched largely that of healthy men and women of same age.

Adult↗
PubMed1994

FIL2, an extracellular Leucine-Rich Repeat protein, is specifically expressed in Antirrhinum flowers.

The expression of the Antirrhinum gene FIL2 is affected in mutants of the homeotic transcription factor DEFICIENS. Northern and Western blot analyses showed that FIL2 in wild-type Antirrhinum flowers is expressed weakly in the petals and more abundantly in the reproductive organs; the gene is active in the filaments and anthers of stamens, and in the stigma and transmitting tissue of the carpels. The FIL2 protein is glycosylated with high mannose type glycan chains and is located in the middle lamella of the extracellular matrix. The amino acid sequence contains 10 tandem repeats, the composition of which is similar to the Leucine-Rich Repeat (LRR) motif found in mammals, Drosophila and yeast. The possibility that FIL2 might be a component of a cellular signalling mechanism, involving LRR-mediated protein-protein interactions is discussed.

Amino Acid Sequence↗
PubMed1994

Effects of training on blood lactate-running speed relationship in thoroughbred racehorses.

In this study the effects of training history on the results of a standardized two-speed test in competing Thoroughbreds were investigated during a racing season. For nine Thoroughbreds, 1,755 training days were recorded. Within the observation period each horse completed a two-speed field test at intervals of 6-8 wk to determine its running velocity (v) eliciting blood lactate concentrations of 4 (v4) and 12 mmol/l (v12). Horses performed 29 two-speed tests. Changes of v4 and v12 in a horse between two consecutive tests were used to assess effects of training history variables calculated for the period between two consecutive tests. The percentage of days with gallop workouts between two consecutive tests showed a significant correlation with changes in v4 (r = 0.71, P < 0.01) and v12 (r = 0.56, P < 0.05). The number of gallop workouts (r = 0.60, P < 0.05) and the total time of training (r = 0.58, P < 0.05) correlated with the change of v4. Furthermore the percentage of days without training was negatively correlated to changes of v4 (r = -0.75, P < 0.01) and v12 (r = -0.56, P < 0.05). Therefore the actual training caused changes in the blood lactate-running speed relationship despite its relatively low volume, intensity, and frequency. Future studies have to evaluate how the training variables can be changed to improve the training effects on the blood lactate-running speed relationship of competing Thoroughbreds.

Animals↗
PubMed1994

Placebo-controlled double-blind study examining the effectiveness of an hypericum preparation in 105 mildly depressed patients.

One hundred and five outpatients with mild depressions of short duration were treated in a double-blind study with either 3 x 300 mg hypericum extract or placebo. The therapy phase was 4 weeks. The effectiveness was judged according to the Hamilton Depression Scale after 2 and 4 weeks. The values of the mean basic score in these periods fell from 15.8 to 9.6 or 7.2 in the active group, and in the placebo group, from 15.8 to 12.3 and 11.3. The differences between active and placebo groups were statistically significant with P < .05 and P < .01 achieved after 2 and 4 weeks, respectively. In the active group, 28 of 42 patients (67%) and, in the placebo group, 13 of 47 patients (28%) responded to treatment. Notable side effects were not found.

Adult↗
PubMed1994

Patient's and doctor's delay in primary breast cancer. Prognostic implications.

In a study of 7,608 patients with primary breast cancer patient's and doctor's delay were examined in relation to age, tumour size, grade of anaplasia, and number of positive lymph nodes. The delays were arbitrarily divided into the following intervals: Short (0-14 days), intermediate (15-60 days) and long (> 60 days). The well-established patient and tumour characteristics were shown to have prognostic significance. Similarly the delays showed significant influence on survival. A long patient's delay was associated with an unfavourable outcome, as compared with a short delay. On the contrary, the prognosis was superior for patients with a long doctor's delay compared to those with a short doctor's delay. Overall, when corrected for age, the prognostic value of delay in terms of mortality increased by 24% for a long patient's delay compared to a shorter and by 13% for a short doctor's delay compared to a longer. This indicates that doctors are capable of distinguishing between more and less aggressive malignancies. The study also suggests that all sources of delays should be kept at a minimum.

Adult↗
PubMed1993

[St. John's wort extract in the ambulatory therapy of depression. Attention and reaction ability are preserved].

METHOD: In a placebo-controlled, randomized, double-blind trial involving outpatients with mild to moderately severe depression, an extract of St. John's wort (Hypericum), LI 160, a herbal antidepressant was tested for efficacy and tolerability, as well as for possible negative effects on cognitive performance. RESULTS: The responder rate to treatment with the extract was 66.6% as compared with only 26.7% with placebo. The treatment was very well tolerated; only in two patients did transient minor side effects occur under LI 160. No impairment of cognitive performance was observed: during the trial, Hypericum did not lead to any impairment of attention, concentration or reaction.

Adult↗
PubMed1993

Complementary floral homeotic phenotypes result from opposite orientations of a transposon at the plena locus of Antirrhinum.

Recessive mutations at the plena (ple) locus result in a homeotic conversion of sex organs to sterile perianth organs in flowers of Antirrhinum majus. A complementary phenotype, in which sex organs replace sterile organs, is conferred by semidominant ovulata mutations. The ple locus was identified and isolated using a homologous gene, agamous from Arabidopsis, as a probe. The expression of ple is normally restricted to the inner two whorls of the flower, where sex organs develop. However, in ovulata mutants, ple is expressed ectopically in the outer two whorls of the flower and in vegetative organs. These mutants correspond to gain-of-function alleles of ple, suggesting that ple is sufficient for promoting sex organ development within the context of the flower. The plena and ovulata phenotypes result from opposite orientations of the transposon Tam3 inserted in the large intron of ple.

Alleles↗
PubMed1993

NTGLO: a tobacco homologue of the GLOBOSA floral homeotic gene of Antirrhinum majus: cDNA sequence and expression pattern.

We report the cloning and DNA sequence of a cDNA from Nicotiana tabacum, NTGLO, as well as the pattern of expression of the NTGLO gene in wild-type tobacco plants. The NTGLO cDNA encodes a protein of 209 amino acids, which shows 73% identity with the GLO protein encoded by the GLO gene of Antirrhinum majus, a homeotic gene involved in the genetic control of flower development. Northern blot analysis shows that the NTGLO gene is expressed mainly in floral organs and, within the flower, expression is restricted to petals and stamens. The NTGLO gene most probably represents a true homologue of the GLO gene because: i) the MADS boxes, of the two genes are highly homologous (56 out of 58 amino acids are identical): ii) at the carboxy-terminal a block of 19 amino acids is perfectly conserved between the NTGLO and GLO proteins and iii) their expression patterns in floral organs are identical.

Amino Acid Sequence↗
PubMed1993

Floral development and expression of floral homeotic genes are influenced by cytokinins.

Tobacco plants that are somatic mosaics for the expression of a cytokinin-synthesizing gene have viviparous leaves. Epiphyllous buds can be either vegetative or floral. Floral adventitious buds can be either normal or abnormal. Abnormalities of floral development correlate with: (i) a local activation of the cytokinin-synthesizing gene, (ii) a drastic increase in floral cytokinin content, and (iii) a decrease in the steady-state levels of mRNA homologous of the homeotic genes DEFA, GLO and PLENA of Antirrhinum majus. Thus, these data show in planta that cytokinins, a class of phytohormones, are able to alter the development of floral organs and to decrease the expression of three homeotic floral genes.

Base Sequence↗