PubMed Health⌕ Search

Biomedical subjects

C E Hansen

Publications and source records attributed to C E Hansen.

At least 19 recordsLinked to original sources

Characterization of peptides formed during fermentation of cocoa bean.

Analysis by SDS-PAGE and GPC-MS of fermented cocoa extracts shows changes in the amount and composition of the major proteins, accompanied by formation of complex distributions of peptides. MS/MS studies and application of SEQUEST sequencing software have allowed identification of two related peptides, a hexapeptide and a nonapeptide, formed from vicilin, one of the cocoa storage proteins. Time course studies of the two peptides show different abundance profiles and indicate, in part, production of the hexapeptide from the nonapeptide.

Cacao↗

Isolation and characterisation of cell wall polysaccharides from cocoa (Theobroma cacao L.) beans.

Cell wall material (CWM) was prepared from sun-dried cocoa (Theobroma cacao L.) bean cotyledons before and after fermentation. The monosaccharide composition of the CWM was identical for unfermented and fermented beans. Polysaccharides of the CWM were solubilised by sequential extraction with 0.05 M trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA), 0.05 M Na2CO3, and 1 M, 4 M and 8 M KOH. The non-cellulosic sugar composition for each fraction was similar for unfermented and fermented samples, indicating that fermentation caused no significant modification of the structural features of individual cell wall polysaccharides. Pectic polysaccharides accounted for 60% of the cell wall polysaccharides but only small amounts could be solubilised in solutions of CDTA, Na2CO3, and 1 M and 4 M KOH. The bulk of the pectic polysaccharides were solubilised in 8 M KOH and were characterised by a rhamnogalacturonan backbone heavily substituted with side-chains of 5-linked arabinose and 4-linked galactose. Linkage analysis indicated the presence of additional acidic polysaccharides, including a xylogalacturonan and a glucuronoxylan. Cellulose, xyloglucan and a galactoglucomannan accounted for 28%, 8% and 3% of the cell wall polysaccharides, respectively. It is concluded that the types and structural features of cell wall polysaccharides in cocoa beans resemble those found in the parenchymatous tissue of many fruits and vegetables rather than those reported for many seed storage polysaccharides.

Cacao↗

Psychosocial factors as predictors of unsafe sexual practices among young adults.

This study examined the influence of both psychosocial constructs and demographic features on the sexual risk-taking behavior of young adults. Three hundred seventy-four students between the ages of 18 and 29 were drawn from a medium-sized university. All participants were assessed using measures that included the AIDS Coping and Change Survey, the AIDS Psychosocial Scale, and the AIDS Knowledge and Attitudes Survey. Descriptive statistics were calculated for levels of HIV risk behavior (failure to use condoms combined with casual or anonymous sexual partners), HIV/AIDS knowledge, alcohol and drug use, sexual history, and other demographic features. Factor analysis was then used to examine the latent factors associated with HIV risk behavior. All confirmed factors and demographic items that were shown to be significantly correlated with HIV risk behavior were then examined for predictive ability using a regression analysis. Ten factors or variables were found to be predictive of HIV risk behavior, including a Developmental Factor which was found to be moderately predictive of HIV risk behavior. Other predictors included Resistance to Change in response to AIDS; Perceived Risk of exposure, the influence of peer groups, age, alcohol use, marijuana use; a history of infidelity; a younger age of sexual initiation; and a lower self-efficacy.

Acquired Immunodeficiency Syndrome↗

Glycosaminoglycan antibodies in endocrine ophthalmopathy.

An increased accumulation of glycosaminoglycans (GAG) in the orbita has been reported in endocrine ophthalmopathy (EO). In this study we investigated whether antibodies directed against GAG are present in the sera of 52 EO patients and 47 healthy controls. Three out of 52 patients exhibited low titers of antinuclear antibodies and all patients were negative for antibodies against extractable nuclear antigens. Isotype IgG antibodies were detected by means of an ELISA using hyaluronic acid and dermatan sulfate as antigens. Values were expressed as optical density at 405 nm. In comparison to the control group (0.445, 0.364, 0.588; median, 25th, 75th percentile) significantly (p < 0.001) higher hyaluronic acid antibody levels were found in EO patients (0.626, 0.473, 0.801). Untreated patients had significantly higher hyaluronic acid antibody values compared to controls (0.770 vs 0.437, median, p < 0.005). Thyroid status or antithyroid treatment did not influence binding of hyaluronic acid antibodies. When screening for dermatan sulfate antibodies no such difference could be observed between patients and controls. Thus, the detection of GAG antibodies in EO patients emphasizes the important role of glycosaminoglycans in the pathogenesis of thyroid eye disease.

Adolescent↗

Evidence for a cellular gene with potential oncogenic activity in plants.

During tumor inception in crown gall disease, a portion of the tumor-inducing (Ti) plasmid, the transferred DNA (T-DNA), is integrated into the genome of the plant cell. Autonomous growth of the transformants requires expression of genes in the tmr and tms regions of the T-DNA, which code for enzymes concerned with biosynthesis of the plant growth hormones cytokinin and auxin, respectively. We show that a mutation of the Habituated leaf gene, Hl, of tobacco can compensate for a defective tmr locus in expression of the tumor phenotype. This provides evidence that a specific host-cell gene has an oncogenic function similar to tmr in the T-DNA.

Cell Cycle↗

Bisexuality reconsidered: an idea in pursuit of a definition.

This paper examines the confusion and conflict stemming from the inability of sexological research to establish a reliable operational definition of the bisexual condition. An examination of current research assumptions, definitions, and limitations revealed several "errors" which predispose most investigations to controversial or insignificant results. These errors include the researcher's: erotophobia, dualistic thinking, use of "self-labels," and most important, misuse of the Kinsey Scale as a basic definitional assumption. This paper concludes with a description of an alternative research model and methodology for bisexuality research. This new model eschews subject labeling and proposes a two-axis system for operationally defining bisexuality and for generating testable hypotheses.

Extramarital Relations↗

Concentration Gradients of trans-Zeatin Riboside and trans-Zeatin in the Maize Stem: Measurement by a Specific Enzyme Immunoassay.

A sensitive, specific enzyme immunoassay (EIA) for trans-zeatin riboside (ZR) and trans-zeatin (Z) in the 0.3 to 30 picomole range has been described. The reliability of the method for measuring ZR + Z in partially purified extracts of Zea mays L. tissues was verified by highperformance liquid chromatography. EIA measurements showed that there was a concentration gradient of ZR + Z along the length of the Zea stem. The topmost internodes, internodes 7 and 8 counting from the coleoptilar node, had the highest concentration ( approximately 130 picomoles per gram fresh weight). Moving basipetally, the concentration dropped approximately 10-fold to a minimum at internode 4, and then increased slightly in internodes 2 and 3. There were also gradients within each internode. The five lowest internodes contained the highest concentrations toward their apical end, the region which included the node; this asymmetry was less pronounced near the top of the plant.

Journal Article↗

Zimeldine versus amitriptyline in endogenous depression. A double-blind study with special reference to effects on liver function.

In a double-blind comparison of 21 inpatients with endogenous depression 225 mg zimeldine demonstrated the same degree of antidepressive efficacy as 150 mg amitriptyline after 4 weeks of treatment. Only "sleep disturbances" on the Hamilton Rating Scale for Depression (HRS) showed significant (P less than 0.05) improvement with amitriptyline. Only small differences in the frequency of side effects were seen. In the zimeldine group, increased sweating and headache were more pronounced, while the amitriptyline patients more often reported dry mouth and constipation. Body weight was not significantly changed by either treatment. In the zimeldine group, treatment had to be interrupted in three patients due to hypersensitivity reactions in the form of drug fever. Three other patients in the zimeldine group showed clinically significant elevation of liver enzymes. Hypersensitivity reactions and abnormal blood chemistry were both reversible. The adverse reactions are discussed, the cause of the occurrence remaining unknown.

Adult↗

Formation of (4R)- and (4S)-4-hydroxyochratoxin A and 10-hydroxyochratoxin A from Ochratoxin A by rabbit liver microsomes.

Three metabolites were formed from ochratoxin A in the presence of rabbit liver microsomal fractions and NADPH. They were isolated by extraction, thin-layer chromatography, and high-pressure liquid chromatography. Two of them were identified as (4R)- and (4S)-4-hydroxyochratoxin A. It is suggested on the basis of mass and nuclear magnetic resonance spectroscopy that the third metabolite is 10-hydroxyochratoxin A. The formation of the metabolites was inhibited by carbon monoxide and metyrapone and was stimulated when microsomes from phenobarbital-treated animals were used. The results suggest that cytochrome P-450 catalyzes the formation of these metabolites.

Animals↗

Metabolism of ochratoxin A by primary cultures of rat hepatocytes.

Association of ochratoxin A with cultured rat hepatocytes occurs at 4 degrees C, and the saturation level in the medium is 0.3 mM ochratoxin A, with maximal binding after 60 min. At 37 degrees C the level of cell-associated ochratoxin A increased up to 6 h and remained at 2 nmol of toxin per mg of cell protein for 30 h. With increasing concentrations of ochratoxin A, increasing amounts of the toxin accumulated in the cells; saturation occurred at a concentration of 0.3 mM. Ochratoxin A was metabolized by hepatocytes at 37 degrees. (4R)-4-Hydroxyochratoxin A appeared in the medium at a maximal level (about 30 nmol/mg of cell protein) at an ochratoxin A concentration of 0.25 mM after 48 h of incubation. Small amounts of (4S)-4-hydroxyochratoxin A were detected only after incubation for 22 h or longer.

Animals↗

Formation of (4R)- and (4S)-4-hydroxyochratoxin A from ochratoxin A by liver microsomes from various species.

Two metabolic products were formed from ochratoxin A by human, pig, and rat liver microsomal fractions in the presence of reduced nicotinamide adenine dinucleotide phosphate. They were isolated from the incubation mixture in the presence of pig liver microsomes by extraction, thin-layer chromatography, and high-pressure liquid chromatography Their structures are suggested to be (4R)- and (4S)-4-hydroxyochratoxin A on the basis of mass and nuclear magnetic resonance spectroscopy. Km and the maximum velocity for the formation of the two metabolites by human, pig, and rat microsomes were determined. Their formation was inhibited by carbon monoxide and metyrapone. The results indicate that the microsomal hydroxylation system is a cytochrome P-450 and that different species are involved in the formation of the two epimeric forms of 4-hydroxyochratoxin A.

Animals↗

Amoxapine versus amitriptyline in endogenous depression. A double-blind study.

A new antidepressant, amoxapine, which is a dibenzoxazepine deprivative, was compared with amitriptyline in a randomised double-blind trial. Forty-eight patients were included and 41 completed a 4-week treatment. Most of the patients were maintained on 150 mg daily. Assessments were made by the Hamilton Psychiatric Rating Scale for Depression (HAM-D), Nurses' Observation Scale for Inpatient Evaluation (NOSIE), Clinical Global Impression (CGI) scale and Patient's Self-Evaluation. The total HAM-D score was considerably reduced in the majority of the patients. Amitriptyline was the most effective with regard to symptoms included in the factor Sleep Disturbances and-secondary maybe-towards some items included in the factor Somatization. For the remaining items,including the items of the factors Anxiety/Depression and Apathy, the last score was lower in the amoxapine group than in those treated with amitriptyline. Among the unipolar cases the amoxapine treated patients were more satisfied with regard to efficacy (P = 6.3%). The frequency of side effects such as tremor and dizziness was considerably lower in the amoxapine group. In total, the side effects lasted longer in the amitriptyline group. We conclude that amoxapine seems to be an effective antidepressant with a low frequency of side effects.

Adult↗

Effect of simultaneous treatment with low doses of perphenazine on plasma and urine concentrations of nortriptyline and 10-hydroxynortriptyline.

Plasma levels of nortriptyline and perphenazine were measured in six patients on continuous nortriptyline treatment before, during and after oral administration of perphenazine 4 mg t.i.d. In four patients the plasma levels of the conjugated and unconjugated principal metabolite 10-hydroxynortriptyline were also measured. Urinary excretion of conjugated and unconjugated 10-hydroxynortriptyline and plasma levels of perphenazine were determined in all six patients. During treatment with perphenazine two patients showed a slight increase in the plasma level of nortriptyline. The changes in metabolite excretion rate were inconclusive. Thus, there did not appear to be any important pharmacokinetic interaction between the two drugs at the doses used, which were normal therapeutic doses. The previously reported inhibitory effect of perphenazine on the metabolism of nortriptyline probably depended therefore, either on administration of a higher dose of perphenazine, or on treatment in the reverse sequence--a single dose of nortriptyline was given to patients already receiving perphenazine.

Adult↗

Self-inhibiting action of nortriptylin's antidepressive effect at high plasma levels: a randomized double-blind study controlled by plasma concentrations in patients with endogenous depression.

Below the toxic plasma level of nortriptyline (NT) an upper therapeutic limit has been postulated in patients with endogenous depression. If so the clinical significance is obvious and a double-blind, randomized study was performed in order to solve this problem. Two groups of patients were controlled at different plasma levels (less than 150 ng/ml and less than 180 ng/ml). The degree of depression was rated weekly. Only about one third (n equals 24) of the patients originally included, were carried through the full protocol, the most prominent reason for drop out beeing spontaneous remission during an initial placebo period. After 4 weeks of NT treatment the majority in the high level group was still depressed, but the difference barely significant (P equals 5.5%). However, a randomized reduction of the plasma level among the patients at the high level resulted in a significant correlation to remission. Evaluation of the total material after 6 weeks of NT treatment demonstrated a strong correlation of high plasma level to poor antidepressive effect of NT. No correlation could be obtained between side-effects, which were few, and plasma level. The non-proteinbound fraction in plasma was found to 7% (SD 1.83) by simultaneous determinations of NT in plasma and CSF in 13 patients. The variation in the proteinbinding was not likely to invalidate the over all results based on total NT determination. A therapeutic plasma range of 50-150 ng/ml is recommended.

Adult↗

Therapeutic control of plasma concentrations and long-term effect of nortriptyline in recurrent affective disorders.

Based on the evidence that therapeutic plasma concentration range in fact exists for the tricyclic antidepressant drug, Nortriptyline (range 50-150 ng/ml), three different investigations were under taken in order to clarify some clinical pharmacological problems during long-term treatment with this drug. The possible prophlactic effect of the drug in recurrent affective disorders was specially examined in a group of patients with a high risk of episodes in their unipolar manic-depressive disease. The results highly demonstrate the value of monitoring plasma levels in achieving therapeutic control. Depressive relapses during treatment, for months and years, were only related to therapeutic insufficient plasma levels of the drug.

Adolescent↗