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H Dittrich

Publications and source records attributed to H Dittrich.

At least 19 recordsLinked to original sources
PubMed1992

The jasmonate precursor, 12-oxo-phytodienoic acid, induces phytoalexin synthesis in Petroselinum crispum cell cultures.

The pentacyclic biosynthetic precursor of jasmonic acid, 12-oxo-phytodienoic acid, was found to induce synthesis of the major flavonoid, apiin, in cell suspension cultures of Petroselinum crispum. The accumulation of apiin was preceded by an increase in the relative levels of poly (A)+ RNAs that code for the flavonoid biosynthetic enzymes phenylalanine ammonia lyase, 4-coumarate:CoA ligase and chalcone synthase, Poly (A)+ RNAs reached maximal levels at approximately 4-6 h after the addition of elicitor while flavonoids continued to accumulate in the cultures for at least 6 days. 12-Oxo-phytodienoic acid is the first pentacyclic precursor in the jasmonic acid biosynthetic chain which functions as a signal transducer for phytoalexin induction.

Blotting, Northern↗
PubMed1992

Pitfalls in the histochemical demonstration of alpha-glucan phosphorylase activity in glycogen-depleted skeletal muscle fibres.

In the present communication, an investigation is described into the reliability of histochemical methods for the demonstration of alpha-glucan phosphorylase activity in glycogen-depleted skeletal muscle fibres. Human skeletal muscles with glycogen-depleted fibres from patients with diseases of the neuromuscular system and from subjects who had suffered from malignant hyperthermia were used for the study. The location of phosphorylase activity and glycogen was demonstrated with histochemical techniques. Biochemical techniques were used to assay the activity of phosphorylase and the content of glycogen. Biochemical determinations of phosphorylase activity did frequently not reveal significant differences between glycogen-depleted and non-depleted skeletal muscle fibres. In contrast, all histochemical methods investigated, showed little or no phosphorylase activity in the glycogen depleted fibres, indicating that none of the existing histochemical methods revealed reliable staining results in these fibres. Owing to the invalid staining results of the histochemical methods for glycogen-depleted muscle fibres, it is necessary that for metabolic studies a biochemical assay for phosphorylase activity is also to be performed.

Glycogen↗
PubMed1992

[The content of DNA, RNA and protein and the fresh weight:DNA, protein:DNA and RNA:DNA ratios in tissue of male calves, bulls, short-scrotum bulls and oxen during the growth period].

In male calves, in bulls, in short scrotum bulls and in oxen of different age the content of DNA, RNA and protein in various tissues (cerebrum, cerebellum, spinal cord, ventricles, lung, liver, cortex of the kidney, spleen, testicles, M. semimembranosus) was analysed. The fresh weight: DNA-, the protein: DNA- and the RNA: DNA-ratios were calculated. In the age of 78 weeks the short scrotum bulls had a body weight of 577 +/- 44, the bulls of 550 +/- 21 and the oxen of 462 +/- 41 kg. The testicles of the short scrotum bulls were smaller than that of the bulls. The differences in the content of DNA, RNA and protein per g tissue between male calves, bulls, short scrotum bulls and oxen of the same age were in part significant. The total content of DNA, of RNA and of protein for the 78 weeks old as well as the number of nuclei of the lung, the liver, the spleen and the testicles for the 6 and 78 weeks old animals were calculated. The biochemical parameters can be used for the characterization of the inhibition of growth of the different organs of calves and cattle by malnutrition and diseases.

Animals↗
PubMed1991

[The content of beta-carotene, vitamin A and ascorbic acid in different tissues of bulls, short-scrotum bulls and oxen of different body weights].

Analyses of the liver of bulls of different age show, that the concentration of beta-carotene in the age of 6 to that of 25 weeks increased only from 0.43 +/- 0.16 to 1.66 +/- 0.27 and that of vitamin A from 11.49 +/- 5.87 to 13.90 +/- 5.21 micrograms/g fresh weight. The concentration of beta-carotene and of vitamin A in the testis of bulls and of short scrotum bulls up to an age of 15 weeks was similar; thereafter the concentration in the short scrotum bulls was higher. At an age of 72 weeks the concentration of vitamin A in the liver of bulls (219.17 +/- 51.86) was higher (p less than 0.01) than in that of the short scrotum bulls (144.11 +/- 27.79) and that of the oxen (135.51 +/- 41.26 micrograms/g fresh weight). Analyses of the concentration of ascorbic acid in 8 different tissues of bulls and short scrotum bulls at 6 various periods show, that the highest values mostly were found in December.

Animals↗
PubMed1991

Molecular cloning, expression, and induction of berberine bridge enzyme, an enzyme essential to the formation of benzophenanthridine alkaloids in the response of plants to pathogenic attack.

The berberine bridge enzyme [(S)-reticuline: oxygen oxidoreductase (methylene-bridge-forming), EC 1.5.3.9] is a vesicular plant enzyme that catalyzes the formation of the berberine bridgehead carbon of (S)-scoulerine from the N-methyl carbon of (S)-reticuline in a specific, unparalleled reaction along the biosynthetic pathway that leads to benzophenanthridine alkaloids. Cytotoxic benzophenanthridine alkaloids are accumulated in certain species of Papaveraceae and Fumariaceae in response to pathogenic attack and, therefore, function as phytoalexins. The berberine bridge enzyme has been purified to homogeneity from elicited cell-suspension cultures of Eschscholtzia californica, and partial amino acid sequences have been determined. A cDNA, isolated from a Agt11 cDNA bank of elicited E. californica cell-suspension cultures, coded for an open reading frame of 538 amino acids. The first 22 amino acids constitute the putative signal peptide. The mature protein has a Mr of 57,352, excluding carbohydrate. The berberine bridge enzyme was heterologously expressed in a catalytically active form in Saccharomyces cerevisiae. Southern hybridization with genomic DNA suggests that there is only one gene for the enzyme in the E. californica genome. Hybridized RNA blots from elicited E. californica cell-suspension cultures revealed a rapid and transient increase in poly(A)+ RNA levels that preceded both the increase in enzyme activity and the accumulation of benzophenanthridine alkaloids, emphasizing the integral role of the berberine bridge enzyme in the plant response to pathogens.

Alkaloids↗
PubMed1991

[Content of beta-carotene, vitamin E and ascorbic acid in blood plasma of female calves, cattle, bulls, castrates and ox throughout the course of the year].

The concentration of beta-carotin, of vitamin E and of ascorbic acid in the plasma of female calves (beginning with an age of 4 weeks), of cows in the 2nd and 5th lactation, of bulls, of short scrotum bulls and of oxes in the course of the year was analysed. The concentration of beta-carotin in the plasma of calves after driving up to pasture increased slower than that of cows. After transition to stable feeding there was a significant decrease in the concentration after 4 weeks. During the period of suckling the concentration of vitamin E in the plasma of calves was low. After transition to pasture the concentration of vitamin E in the plasma of calves increased slower than in that of the cows. The concentration of ascorbic acid in the plasma during the winter was higher than during the summer. There was no influence of experimental cryptorchism or castration on the mentioned values.

Aging↗
PubMed1991

[The content of minerals and Fe, Cu and Zn in blood plasma, in erythrocytes and in 10 different tissues of bulls, short scrotum bulls and oxen].

The concentrations of minerals (Ca, Mg, Na, K, total-P) and of trace elements (Fe, Cu, Zn) in the plasma and erythrocytes of bulls, of experimentally induced cryptorchids (Muchsen) and of oxen of the breed Holstein-Friesian and of bulls and cryptorchids of a hybrid breed with a high portion of meat-cattle were investigated. Further the concentrations in various tissues (M. semimembranosus, M. longissimus dorsi, left and right ventricle, liver, kidney, adrenal glands, lung, spleen, testis) in bulls, cryptorchids and oxen of the breed Holstein-Friesian were analyzed. The differences of some concentrations of various elements in some tissues are discussed relative to their genesis and significance.

Animals↗
PubMed1991

Factors associated with recurrent myocardial infarction within one year after acute myocardial infarction.

In a large population of patients (n = 3666) who were discharged from the hospital after acute myocardial infarction and followed up for 1 year, factors associated with recurrent nonfatal (n = 171) or fatal (n = 74) infarction were identified. Also, the effects of combining various end points (recurrent nonfatal or fatal infarction and other cardiac death) in multivariate analyses, a practice common in many small studies that evaluate the predictive-value of various treatments or special tests, was examined. In univariate analyses, patients with nonfatal recurrent infarction did not differ with respect to age or gender from infarct-free survivors, but they more often had a history of previous myocardial infarction, congestive heart failure, angina pectoris, and diabetes; more severe pulmonary congestion was present on chest x-ray during the admission, and a non-Q wave index infarction was more frequent. Patients with either a fatal or nonfatal recurrent infarction had more angina pectoris during follow-up (55% to 60%) compared with 27% in event-free survivors and 31% in patients who died of other cardiac causes in whom this factor could be assessed before death. In multivariate analyses, historical and clinical prognostic factors were ranked differently for fatal or nonfatal reinfarction and other cardiac causes of death; angina pectoris at follow-up was highly related to recurrent infarction (fatal or nonfatal), along with a history of diabetes, and a non-Q wave index infarction. These factors were not independently related to other causes of cardiac death.(ABSTRACT TRUNCATED AT 250 WORDS)

California↗
PubMed1991

Trends in use of coronary angiography in subacute phase of myocardial infarction.

BACKGROUND: Most patients do not undergo acute reperfusion after myocardial infarction, and which of these patients should undergo coronary angiography is still debated. METHODS AND RESULTS: We analyzed the 1-year clinical outcomes and rates of coronary angiography performed as late as 60 days after myocardial infarction in 3,804 patients admitted between 1979 and 1988 and followed in six different centers. Patients less than 75 years old were classified into low-, medium-, and high-risk groups using a multivariate analysis of historical and clinical variables gathered during the first 8 hospital days. Patients who underwent early reperfusion (17%, all after 1984) were analyzed separately. To analyze time trends, patients were compared before and after mid-1984. Mortalities from day 9 through 1 year were similar for the two time periods in the low- (3.3% versus 2.5%) and medium-risk (7.4% versus 5.6%) groups, but mortality was lower for the high-risk group after 1984 (31.6% versus 20.0%). The proportion of patients undergoing coronary angiography increased dramatically in each group after 1984 (low risk, 18% versus 48%; medium risk, 23% versus 49%; high risk, 10% versus 32%, before and after 1984, respectively). Furthermore, a large percentage of patients (more than 40%) in the low-risk group did not have at least one of the indications for coronary angiography recently recommended by a joint task force. Among patients undergoing coronary angiography, the proportion of patients with three-vessel coronary artery disease decreased after 1984, whereas the proportion undergoing mechanical revascularization in the year after infarction increased in all risk groups. CONCLUSIONS: Despite the recent development of noninvasive techniques with high sensitivity for detecting high-risk patients after myocardial infarction, coronary angiography is being performed increasingly in all patients, including those determined to be at low risk for complications based on clinical data. The economic consequences of such a trend could be considerable, and its impact requires careful analysis.

Age Factors↗
PubMed1990

Predicting 1-year outcome following acute myocardial infarction: physicians versus computers.

Whether decision rules derived statistically from patient data can produce better decisions than an expert clinician or a model of the expert clinician (expert system) is controversial. We examined this issue in the context of predicting cardiac death by 1 year for patients discharged from the hospital following acute myocardial infarction. Decision rules were derived from a base sample of 781 patients. These decision rules and three experienced cardiologists then estimated probability of death by 1 year for each patient in a separate test sample (n = 400). In our evaluation of the performance of the decision rules and physicians, we detected no differences, although the decision rules and physicians tended to classify the patients somewhat differently. Further multivariate analyses on the physicians' predictions showed that two of the physicians paid attention to somewhat different variables than the third physician. Lack of agreement among expert cardiologists would complicate modeling of a consensual decision-making process within the framework of an expert system.

Aged↗
PubMed1990

Decreased adrenergic sensitivity in patients with hypothyroidism.

Cardiovascular sensitivity to catecholamines was assessed in 15 patients with hypothyroidism (mean [+/- SEM] thyroxine [T4] index 2.7 +/- 0.5 micrograms/100 ml, thyroid stimulating hormone [TSH] 136.9 +/- 48.3 microU/ml), aged 45 +/- 4 years and in 8 healthy control subjects. The study was repeated in 10 patients with hypothyroidism 4.0 +/- 0.5 months after thyroid replacement therapy (T4 index 9.9 +/- 2.1 micrograms/100 ml, TSH 3.5 +/- 1.3 microU/ml). In addition, basal, average and maximal heart rates were measured using 24 h ambulatory electrocardiographic (ECG) monitoring, and plasma levels of epinephrine and norepinephrine were determined before and after thyroid replacement. Heart rate increased less after bolus injection of 0.8, 1.6 and 3.2 micrograms of isoproterenol in the hypothyroid (10 +/- 2, 15 +/- 2 and 21 +/- 4 beats/min, respectively) than in the euthyroid (16 +/- 3, 22 +/- 3 and 30 +/- 4 beats/min, respectively) state (p less than 0.05). Control subjects reacted similarly to patients receiving thyroid replacement. Basal heart rate (64 +/- 3 versus 68 +/- 3 beats/min, p less than 0.05) and maximal heart rate (116 +/- 5 versus 133 +/- 5 beats/min, p less than 0.05) were lower on 24 h ambulatory ECG monitoring in the hypothyroid than euthyroid state despite higher basal plasma norepinephrine levels (394 +/- 45 versus 315 +/- 45 pg/ml, p less than 0.05). Thus, patients with hypothyroidism display a decreased cardiac chronotropic response to beta-adrenergic stimulation. This may contribute in part to the decreased basal and maximal daily heart rates seen in patients with hypothyroidism, which occurs despite elevated plasma norepinephrine levels.

Adrenergic beta-Agonists↗
PubMed1990

Outlook after acute myocardial infarction in the very elderly compared with that in patients aged 65 to 75 years.

Little is known concerning late outcome and prognostic factors after acute myocardial infarction in the very elderly (greater than 75 years of age). Accordingly, this study compared the clinical course and mortality rate for up to 1 year in a large multicenter data base that included 702 patients greater than 75 years of age (mean +/- SD 81 +/- 4 years), with a less elderly subset of 1,321 patients between 65 and 75 years of age (mean 70 +/- 3 years). The postdischarge 1 year cardiac mortality rate was 17.6% for those greater than 75 years of age compared with 12.0% for patients between 65 and 75 years of age (p less than 0.01). There were differences in the prevalence of several factors, including female gender, history of angina pectoris, history of congestive heart failure, smoking habits and incidence of congestive heart failure during hospitalization. Multivariate analyses of predictors of cardiac death in hospital survivors selected different factors as important in the two age subgroups; age was selected in the 65 to 75 year age group but was not an independent predictor in the very elderly. The survival curves beginning at day 10 for patients 65 to 75 and in those greater than 75 years old were similar for up to 90 days but diverged later. In the very elderly, 63% of late cardiac deaths were sudden or due to new myocardial infarction, similar to the causes of 67% of deaths in the younger age group.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1990

[Dissolution of alloy components from Ni/Cr base alloys by bacterial leaching].

The method of bacterial leaching of non precious dental alloys represents a useful completion of the method arsenal of biological investigations. In contrast to other well known methods it allows to point out small differences in corrosion resistance between alloys of the same type in a biologic system.

Acidithiobacillus thiooxidans↗
PubMed1989

Familial aortic dissecting aneurysm.

A family is described in which nine members over two generations had an aortic dissecting aneurysm or aortic or arterial dilation at a young age. The family has been followed up since 1977 after the death of a second teenager from a kindred of 11. None of the patients had the Marfan syndrome or a history of systemic hypertension. Three members died of ruptured aortic dissecting aneurysm and acute hemopericardium at 14, 18 and 24 years of age, respectively; a fourth member died suddenly at age 48 years, a few years after aortic repair for aneurysmal dilation. One member underwent surgical repair of an ascending aortic dissecting aneurysm at age 18 years and is still alive. Four members are currently under close medical observation for aortic or arterial dilation. Histologic examination of the aortic wall at autopsy or surgery in three patients revealed a loss of elastic fibers, deposition of mucopolysaccharide-like material in the media and cystic medial changes. Types I and III collagen from cultured fibroblasts appeared normal on gel electrophoresis. Results of indirect immunofluorescent studies of the elastin-associated microfibrillar fiber array in skin and fibroblast culture from multiple family members were also normal. This dramatic familial cluster of aortic dissecting aneurysm and aortic or arterial dilation suggests a genetically determined disease of autosomal dominant inheritance although the basic defect remains unknown.

Adolescent↗
PubMed1989

Investigations of trace elements in metastases and primary carcinoma of the prostate.

The concentration of several trace elements (Cd, Zn, Mn, Cr, Pb, Se) as determined both in primary prostatic carcinoma and in metastases of the same patients in unseparated and in separated tissue. In the unseparated tissue a significantly higher amount of all elements studied was found in the primary tumour. Different results were obtained for the concentrations in separated epithelium and stroma as well as in the cellular fractions of metastases and of primary tumour.

Cell Nucleus↗
PubMed1989

Randomized controlled trial of silymarin treatment in patients with cirrhosis of the liver.

Silymarin, the active principle of the milk thistle Silybum marianum, protects experimental animals against various hepatotoxic substances. To determine the effect of silymarin on the outcome of patients with cirrhosis, a double blind, prospective, randomized study was performed in 170 patients with cirrhosis. 87 patients (alcoholic 46, non-alcoholic 41; 61 male, 26 female; Child A, 47; B, 37; C, 3; mean age 57) received 140 mg silymarin three times daily. 83 patients (alcoholic 45, non-alcoholic 38; 62 male, 21 female; Child A, 42; B, 32; C, 9: mean age 58) received a placebo. Non-compliant patients and patients who failed to come to a control were considered as 'drop outs' and were withdrawn from the study. All patients received the same treatment until the last patient entered had finished 2-years of treatment. The mean observation period was 41 months. There were 10 drop outs in the placebo group and 14 in the treatment group. In the placebo group, 37 (+2 drop outs) patients had died, and in 31 of these, death was related to liver disease. In the treatment group, 24 (+4 drop outs) had died, and in 18 of these, death was related to liver disease. The 4-year survival rate was 58 +/- 9% (S.E.) in silymarin-treated patients and 39 +/- 9% in the placebo group (P = 0.036). Analysis of subgroups indicated that treatment was effective in patients with alcoholic cirrhosis (P = 0.01) and in patients initially rated 'Child A' (P = 0.03). No side effects of drug treatment were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

A decision scheme for coronary angiography after acute myocardial infarction.

It is important to select patients in the convalescent phase of acute myocardial infarction in whom knowledge of coronary anatomy may identify those potentially suitable for intervention aimed at improving prognosis. However, differing guidelines have been proposed, and by applying some of these guidelines to our large database of patients after acute myocardial infarction, several problem areas were identified. These include lack of considering patients with resting ischemia beyond day 5 of hospitalization, management of patients with reduced ventricular function or patients not exercise tested, and the role of coronary angiography in the elderly. Based on this experience and further analysis in 1,848 patients surviving beyond day 5 of hospitalization, a modified decision scheme for coronary angiography was developed and then tested in a second population (n = 780). In the new scheme, patients over 75 years of age are considered individually. Those under 75 years of age with severe resting ischemia in the hospital at any time beyond the first 24 hours (18% mortality between day 6 and year 1), and hospital survivors with a history of previous myocardial infarction and clinical or radiographic signs of left ventricular failure in the hospital (25% 1-year mortality after discharge), are recommended for coronary angiography. Among the remaining patients, some will perform an exercise test, and those with an ischemic response or poor workload (11% 1-year mortality) are also assigned to coronary angiography. When an exercise test is not performed, a resting radionuclide left ventricular ejection fraction is recommended, and coronary angiography is considered if the value lies between 0.20 and 0.44 (12% 1-year mortality). This relatively simple scheme does not make general recommendations in the elderly, considers patients with in-hospital left ventricular failure or reduced left ventricular function or both, and approaches the problem of patients who do not perform an exercise test. This general approach would avoid early coronary angiography in patients with an average 1-year mortality risk after discharge of 3% and recommend coronary angiography in those at increased risk (average mortality rate, 16%) who make up about 55% of this population under 75 years of age.

Aged↗