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1.
Eur J Clin Nutr ; 69(7): 850-5, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25351651

ABSTRACT

BACKGROUND/OBJECTIVES: Objective and subjective measurement instruments have been used to estimate energy expenditure (EE) as alternatives to the doubly labeled water (DLW) methodology, but their relative validity for older adults remains uncertain. The purpose of this study was to validate an objective monitor (SenseWear Mini Armband) and a self-report instrument (7-Day Physical Activity Recall, 7D-PAR) relative to the DLW under free-living conditions in older adults. SUBJECTS/METHODS: Twenty-nine older adults (60-78 years) each wore the Mini for 14 consecutive days and completed two 7D-PARs after each week. For each measurement method, activity EE (AEE) was calculated as total EE (TEE)­measured resting metabolic rate (RMR)­diet induced thermogenesis (10% of TEE). TEE and AEE from the Mini and 7D-PAR were each compared with values from the DLW. RESULTS: Equivalence testing indicated that estimates of TEE from the Mini and the 7D-PAR were statistically equivalent to those measured with DLW; however, differences were evident for estimates of AEE. The Mini had smaller mean absolute percent error for TEE (8.0%) and AEE (28.4%) compared with the 7D-PAR (13.8 and 84.5%, respectively) and less systematic bias in the estimates. CONCLUSIONS: The Mini and 7D-PAR provided reasonably valid estimates of TEE but large errors in estimating AEE. The Mini and 7D-PAR have the potential to accurately estimate TEE for older adults.


Subject(s)
Aging , Energy Metabolism , Motor Activity , Actigraphy , Aged , Basal Metabolism , Cohort Studies , Female , Humans , Male , Middle Aged , Reproducibility of Results , Self Report , Thermogenesis
2.
Herz ; 38(4): 367-75, 2013 Jun.
Article in German | MEDLINE | ID: mdl-23604108

ABSTRACT

Clinical studies have consistently shown that there is only a very weak correlation between the angiographically determined severity of coronary artery disease (CAD) and disturbance of regional coronary perfusion. On the other hand, the results of randomized trials with a fractional flow reserve (FFR)-guided coronary intervention (DEFER, FAME I, FAME II) showed that it is not the angiographically determined morphological severity of coronary artery disease but the functional severity determined by FFR that is critical for prognosis and the indications for revascularization. A non-invasive method combining the morphological image of the coronary anatomy with functional imaging of myocardial ischemia is therefore particularly desirable. An obvious solution is the combination of coronary computed tomography angiography (CCTA) with a functional procedure, such as perfusion positron emission tomography (PET), perfusion single photon emission computed tomography (SPECT) or perfusion magnetic resonance imaging (MRI). This can be performed with fusion imaging or with hybrid imaging using PET-CT or SPECT-CT. First trial results with PET CCTA and SPECT CCTA carried out as cardiac hybrid imaging on a 64 slice CT showed a major effect to be a decrease in the number of false positive results, significantly increasing the specificity of CCTA and SPECT. Although the results are promising, due to the previously high costs, low availability and the additional radiation exposure, current data is not yet sufficient to give clear recommendations for the use of hybrid imaging in patients with a low to intermediate risk of CAD. Ongoing prospective studies such as the SPARC or EVINCI trials will bring further clarification here.


Subject(s)
Coronary Artery Disease/diagnosis , Coronary Artery Disease/surgery , Evidence-Based Medicine , Multimodal Imaging/methods , Myocardial Ischemia/diagnosis , Myocardial Ischemia/surgery , Myocardial Revascularization/methods , Chronic Disease , Coronary Artery Disease/complications , Humans , Image Enhancement/methods , Myocardial Ischemia/etiology , Prognosis
3.
Rehabilitation (Stuttg) ; 51(6): 392-7, 2012 Dec.
Article in German | MEDLINE | ID: mdl-22689340

ABSTRACT

BACKGROUND: The aim of this study was to examine how far treatment success in psychosomatic rehabilitation can be predicted by patients' characteristics, therapy motivation and disorder. METHODS: Data of 307 patients with psychosomatic disease were included. External and self-evaluations were operationalized as criterion for success. Data were collected using the Brief Symptom Inventory (BSI), Patients' Questionnaire of Therapy Motivation (PAREMO-20) and Disorder Severity Score (BSS). Hierarchical linear regression analysis was used for data analysis. RESULTS AND CONCLUSIONS: A sceptical attitude, low education and long time of incapacity for work prior to rehabilitation can predict a lower treatment success. High levels of readiness for change and 6-8 working hours daily seem to favourably impact coping with disease in the framework of inpatient psychosomatic rehabilitation.


Subject(s)
Attitude to Health , Disability Evaluation , Employment/statistics & numerical data , Motivation , Psychophysiologic Disorders/epidemiology , Psychophysiologic Disorders/rehabilitation , Severity of Illness Index , Adult , Educational Status , Female , Germany/epidemiology , Humans , Male , Prevalence , Psychophysiologic Disorders/diagnosis , Risk Factors , Treatment Outcome
4.
Water Sci Technol ; 59(9): 1721-6, 2009.
Article in English | MEDLINE | ID: mdl-19448306

ABSTRACT

Odour measurement via olfactometry is expensive and has a low accuracy compared with chemical or physical methods. In addition, olfactometry is not suited for online monitoring. Hence, an accurate online method for emission measurement would be an enormous improvement. There are several options to more or less replace the offline olfactometry by online measurement available today. Most common are H2S-concentration as a single gas parameter and VOC and TOC as composite parameters. A fairly new development are multi sensor arrays, usually referred to as "electronic noses" which carry out non-specific gas measurement and deliver measurement data that can visualized as a fingerprint diagram. This paper outlines the use of these different parameters and compares the results to those gained via olfactometry of several case studies.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/methods , Organic Chemicals/analysis , Hydrogen Sulfide/analysis , Odorants/analysis
5.
Cytotherapy ; 10(4): 320-30, 2008.
Article in English | MEDLINE | ID: mdl-18574765

ABSTRACT

As an archetype of human adult stem cells that can readily be harvested, enriched and expanded in vitro, mesenchymal stromal cells (MSC) have been reported to be of significance for regenerative medicine. The literature is replete with reports on their developmental potentials in pre-clinical model systems. Different preparative protocols have been shown to yield MSC-like cell cultures or even cell lines, from starting materials as diverse as bone marrow, fat tissue, fetal cord blood and peripheral blood. However, MSC are still ill-defined by physical, phenotypic and functional properties. The quality of preparations from different laboratories varies tremendously and the cell products are notoriously heterogeneous. The source and freshness of the starting material, culture media used, presence of animal sera, cytokines, cell density, number of passages upon culture, etc., all have a significant impact on the (1) cell type components and heterogeneity of the initial population, (2) differential expansion of specific subsets, with different potentials of the end products, and (3) long-term functional fate of MSC as well as other types of progenitor cells that are co-cultivated with them. Consequently, there is an urgent need for the development of reliable reagents, common guidelines and standards for MSC preparations and of precise molecular and cellular markers to define subpopulations with diverse pathways of differentiation and divergent potentials.


Subject(s)
Cell Culture Techniques , Coculture Techniques , Mesenchymal Stem Cells , Stromal Cells , Animals , Biomarkers/metabolism , Cell Differentiation , Cell Lineage , Cell Separation , Cells, Cultured , Humans , Intercellular Junctions/metabolism , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/physiology , Phenotype , Stromal Cells/cytology , Stromal Cells/physiology
6.
Brain Behav Immun ; 20(3): 201-9, 2006 May.
Article in English | MEDLINE | ID: mdl-16504463

ABSTRACT

Increased serum levels of inflammatory mediators have been associated with numerous disease states including atherosclerosis, Type II diabetes, hypertension, depression, and overall mortality. We hypothesized that a long-term exercise intervention among older adults would reduce serum inflammatory cytokines, and this reduction would be mediated, in part, by improvements in psychosocial factors and/or by beta-adrenergic receptor mechanisms. Adults age 64 were randomly assigned to either an aerobic exercise treatment (CARDIO) or a flexibility/strength exercise treatment (FLEX) 3 days/week, 45 min/day for 10 months. A subgroup of subjects treated with non-selective beta(1)beta(2) adrenergic antagonists were included to evaluate the potential role of beta-adrenergic receptor adaptations as mediators of an exercise-induced change in inflammation. The inflammatory mediators [C-reactive protein (CRP), IL-6, tumor necrosis factor (TNF)-alpha, and IL-18] and the psychosocial factors (depression, perceived stress, optimism, sense of coherence, and social support) were measured pre- and post-intervention. The CARDIO treatment resulted in significant reductions in serum CRP, IL-6, and IL-18 compared to the FLEX treatment (significant treatment x time interaction, p<.05), whereas TNFalpha declined in both groups (main effect of time, p=.001). However, several psychosocial factors (depression, optimism, and sense of coherence) improved in both groups suggesting that the reduction of CRP, IL-6, and IL-18 in the CARDIO group was not mediated by improvements in psychosocial scores. With respect to the potential role of beta-adrenergic receptors, both CARDIO subjects treated with beta-adrenergic antagonists and those who were not treated with those medications demonstrated similar reductions in serum CRP, IL-6, IL-18, and TNFalpha. In summary, we have observed that an aerobic exercise intervention can significantly reduce serum inflammatory mediators, but beta-adrenergic receptors and psychosocial factors do not appear to be involved.


Subject(s)
Aged/physiology , Exercise/physiology , Exercise/psychology , Inflammation Mediators/blood , Inflammation/blood , Adaptation, Physiological/drug effects , Adrenergic beta-Antagonists/pharmacology , Aged/psychology , Body Mass Index , C-Reactive Protein/analysis , Female , Humans , Inflammation/psychology , Interleukin-18/blood , Interleukin-6/blood , Male , Physical Exertion/physiology , Pliability , Psychology , Reference Values , Tumor Necrosis Factor-alpha/analysis
7.
J Appl Physiol (1985) ; 97(3): 925-9, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15121740

ABSTRACT

Aging and chronic exercise training influence leg venous compliance. Venous compliance affects responses to an orthostatic stress; its effect on tolerance to maximal lower body negative pressure (LBNP) in the elderly is unknown. The purpose of this study was to determine the influence of age and fitness, a surrogate measure of exercise training, on calf venous compliance and tolerance to maximal LBNP in men and women. Forty participants, 10 young fit (YF; age = 22.6 +/- 0.5 yr, peak oxygen uptake = 57.1 +/- 2.0 ml.kg(-1).min(-1)), 10 young unfit (YU; 23.1 +/- 1.0 yr, 41.1 +/- 2.0 ml.kg(-1).min(-1)), 10 older fit (OF; 73.9 +/- 2.0 yr, 39.0 +/- 2.0 ml.kg(-1).min(-1)), and 10 older unfit (OU; 70.9 +/- 1.6 yr, 27.1 +/- 2.0 ml.kg(-1).min(-1)), underwent graded LBNP to presyncope or 4 min at -100 mmHg. By utilizing venous occlusion plethysmography, calf venous compliance was determined by using the first derivative of the pressure-volume relation during cuff pressure reduction. We found that the more fit groups had greater venous compliance than their unfit peers (P < 0.05) as did the young groups compared with their older peers (P < 0.05) such that OU < YU = OF < YF. LBNP tolerance did not differ between groups. In conclusion, these data suggest that aging reduces, and chronic exercise increases, venous compliance. However, these data do not support a significant influence of venous compliance on LBNP tolerance.


Subject(s)
Aging/physiology , Blood Pressure/physiology , Leg/physiology , Lower Body Negative Pressure/methods , Physical Fitness/physiology , Vascular Capacitance/physiology , Veins/physiology , Adaptation, Physiological/physiology , Adult , Age Factors , Compliance , Female , Hemostasis/physiology , Humans , Male , Middle Aged
8.
Nuklearmedizin ; 43(2): 63-8, 2004 Mar.
Article in German | MEDLINE | ID: mdl-15029267

ABSTRACT

AIM: Determination of the biological effect of the alpha emitter (211)At on cellular level as well as the assessment of dosimetric data in a tumour model in vivo. METHODS: Transplantation of malignant ascitic cells in mice intraperitoneally and estimation of tumour characteristics (doubling time of the cells, mean survival of the animals following an i.p. application of a defined tumour cell number). (211)At labelled human serum albumin microspheres B-20 (MSP) of varying activity were injected into tumour bearing mice intraperitoneally. The effectiveness of the therapy was evaluated by means of determination of the duration of cell cycle arrest as well as the microscopic analysis of the rate of abnormal mitotic cells due to radiation induced damage. Furthermore, dose dependence of survival was evaluated. RESULTS: Three days following the intraperitoneally application of 8 x 10(6) tumour cells, 50-600 kBq (211)At-MSP were applied into the abdominal cavity. Considering the volume of ascites at this time and the administered activity, dose calculations were performed. An activity of 50 kBq caused a dose of 0.84 Gy. The increase of radiation induced effect on ascitic tumour cells was correlated with the dose. Between the duration of the cell cycle arrest and the administered activity, a directly proportional correlation was found. The mean survival of non-treated animals was 16.9 +/- 3.7 days. The prolongation of the survival was proportional to the activity administered. Using a dosage of 10 Gy, five animals out of 16 survived. CONCLUSION: Therapy of malignant ascitic cells using (211)At-MSP was effective in vivo. For tumour therapy, the (211)At represents a highly effective alternative to usually applied beta emitters.


Subject(s)
Astatine/therapeutic use , Carcinoma, Ehrlich Tumor/radiotherapy , Animals , Astatine/administration & dosage , Disease Models, Animal , Dose-Response Relationship, Radiation , Drug Carriers , Female , Male , Mice , Mice, Inbred CBA , Microspheres , Serum Albumin
9.
Nucl Med Commun ; 24(6): 643-9, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12766599

ABSTRACT

Patients in persistent vegetative state (PVS) after severe head trauma were investigated with 99mTc-ECD SPECT and 18F-FDG PET to further characterize the degree of brain damage and to obtain insight into changes of brain perfusion and glucose metabolism. 18F-FDG PET and 99mTc-ECD SPECT were performed in 16 patients in PVS. Quantitative PET data were compared with that obtained from seven normal controls. After spatial normalization into Talairach space, global grey matter values and regional data using predefined ROI sets were derived. For comparison of PET and SPECT, regional data were normalized to their individual mean grey matter values. Patients in PVS showed significantly lower values of cerebral glucose metabolism than did the controls. The mean reduction of grey matter values in cortical and subcortical structures was 58%, except in the vermis cerebelli, where only a reduction of 16% was found compared to the controls. Comparing the glucose metabolism and perfusion within the patient group, the pattern of both modalities was similar in the neocortex and internal ganglia. In the cerebellar hemispheres a relatively higher perfusion than glucose metabolism was found. The overall reduction of 58% of glucose metabolism in grey matter structures is in accordance with other PET studies investigating PVS patients with different disease histories. The relative preserved activity of vermis cerebelli seems to be an uncommon finding not described by other authors up to now.


Subject(s)
Brain/diagnostic imaging , Brain/metabolism , Cysteine/analogs & derivatives , Fluorodeoxyglucose F18 , Glucose/metabolism , Organotechnetium Compounds , Persistent Vegetative State/diagnostic imaging , Persistent Vegetative State/metabolism , Tomography, Emission-Computed/methods , Adolescent , Adult , Aged , Brain/blood supply , Cerebrovascular Circulation , Craniocerebral Trauma/complications , Cysteine/pharmacokinetics , Female , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Male , Middle Aged , Organotechnetium Compounds/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Tissue Distribution , Tomography, Emission-Computed, Single-Photon/methods
10.
Eur J Nucl Med Mol Imaging ; 30(7): 1004-8, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12768333

ABSTRACT

3-O-Methyl-6-[(18)F]fluoro-L-DOPA (OMFD) is a major metabolite of 6-[(18)F]fluoro-L-DOPA. Although synthesis of OFMD was primarily established to study the dopaminergic system, as it is an amino acid analogue, uptake in experimental tumours has been found. The aim of this study was to evaluate the applicability of OMFD for brain tumour imaging and to obtain initial estimates of whole-body biodistribution and radiation dosimetry in humans. Nineteen patients with suspected or confirmed brain tumours were investigated with OMFD and dynamic brain PET, complemented by whole-body PET in seven patients. Tracer kinetics were compared for normal brain and intracerebral lesions. Tissue accumulation was quantified with standardised uptake values (SUVs). Whole-body distribution in combination with tracer kinetics from animal experiments was used for the calculation of radiation dosimetry data. On the basis of OMFD PET, viable brain tumour was suspected in 16 patients with SUVs of 3.0+/-0.8 and a tumour to non-tumour ratio of 1.9+/-0.5. Highest tumour and normal brain uptake occurred between 15 and 30 min, with a subsequent slow decrease. Late whole-body tracer distribution was uniform without specific organ accumulation. Elimination occurred via urine. The mean radiation dose to the whole body was estimated at 0.016 mSv/MBq, with the kidneys as dose-critical organ (0.033 mGy/MBq). In conclusion, OMFD enables the visualisation of brain tumours with SUVs similar to other fluorinated amino acids. The whole-body radiation exposure from OMFD is comparable to that from FDG imaging.


Subject(s)
Brain Neoplasms/diagnostic imaging , Brain Neoplasms/metabolism , Dihydroxyphenylalanine/analogs & derivatives , Dihydroxyphenylalanine/pharmacokinetics , Radiometry/methods , Adult , Aged , Body Burden , Female , Humans , Male , Metabolic Clearance Rate , Middle Aged , Organ Specificity , Radiation Dosage , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Tissue Distribution , Tomography, Emission-Computed/methods
11.
Nuklearmedizin ; 42(2): 63-70, 2003.
Article in German | MEDLINE | ID: mdl-12695788

ABSTRACT

UNLABELLED: The detection of TSH-receptor antibodies (TRAb) in patients with Graves' disease is routinely used in nuclear medicine laboratories. This determination has been possible for approximately 3 years with a second generation human TRAb assay. Studies showed that this TRAb determination is diagnostically more sensitive compared to established, porcine TRAb assays. OBJECTIVE: The aim of our study was to investigate, based on a ROC analysis, whether TRAb determination with the new, second generation assay allows a dependable statement about probability of occurrence of relapse after radioiodine therapy in patient suffering from Graves' disease. METHODS: 57 patients were examined with the DYNOtest TRAKhuman (BRAHMS Diagnostica AG, Hennigsdorf) directly before and six months after therapy with radioiodine (dose: 150 Gy). A ROC-analysis was performed to determine positive/negative predictive values depending on different cut-off values. RESULTS: Whereas 21/57 patients became eu- or hypothyroid after six months, 36/57 patients relapsed. Non-relapsed patients showed a significant lower median TRAb titer (4.2 IU/l vs. 19.2 IU/l; p <0.05) compared to relapsed patients. But the positive predictive value conducted 63 and 66, 62 and 66 as well as 63 and 69% (before and after therapy) linked with the cut-offs 1.0, 1.5, and 2.0 IU/l. So it was in areas also achieved by the first generation porcine radio receptor assay. CONCLUSION: An increased sensitivity is achieved undoubtedly with the new DYNOtest TRAKhuman in the diagnostic of Graves' disease. It is not held over the established radio receptor assay concerning the positive predictive value for relapsing patients.


Subject(s)
Graves Disease/diagnostic imaging , Immunoglobulins, Thyroid-Stimulating/blood , Iodine Radioisotopes/therapeutic use , Follow-Up Studies , Graves Disease/blood , Graves Disease/immunology , Humans , Predictive Value of Tests , Radioimmunoassay , Radionuclide Imaging , Sensitivity and Specificity , Thyrotropin , Thyroxine/blood , Time Factors , Triiodothyronine/blood
12.
Nucl Med Commun ; 23(1): 61-6, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11748439

ABSTRACT

Radium (224Ra) is commercially available again for the treatment of ankylosing spondylitis. Twenty patients suffering from ankylosing spondylitis were treated with weekly intravenous (i.v.) injections of 1 MBq 224Ra for 10 weeks. Therapeutic effect was measured by C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and full blood count, as well as a completion of the Bath ankylosing spondylitis functional index (BASFI) questionnaire. Follow-up was done after three and six months. At the end of the treatment course pain and movement restrictions had improved subjectively in 12 out of 20 patients. These patients were also able to discontinue or reduce their analgesic or anti-inflammatory medications. Subjective improvement was well correlated with a reduction of CRP by 45% and BASFI by 73%. At the six-month follow-up, ten patients reported a lasting improvement, whereas two had suffered a relapse. A late therapeutic response after three months was seen in a single patient only. Patients who did not respond to radium had lower initial levels of acute-phase reactants and peripheral joint involvement. Only mild side-effects, e.g. temporary worsening of pain, were observed. Leukocytes and platelets reversibly decreased by 25%, respectively. It is concluded that 224Ra is an effective and safe treatment for ankylosing spondylitis.


Subject(s)
Radiopharmaceuticals/therapeutic use , Radium/therapeutic use , Spondylitis, Ankylosing/radiotherapy , C-Reactive Protein/metabolism , Female , Follow-Up Studies , Humans , Leukocyte Count , Male , Middle Aged , Platelet Count , Radiopharmaceuticals/adverse effects , Radium/adverse effects , Time Factors
13.
Nuklearmedizin ; 40(5): 155-63, 2001 Oct.
Article in German | MEDLINE | ID: mdl-11727628

ABSTRACT

UNLABELLED: The determination of thyroglobulin (Tg) in the follow-up of differentiated thyroid carcinomas (DTC), is routinely used in nuclear medicine, although some problems, like a disturbed recovery-test (RT) or autoantibodies to thyroglobulin (TgAb), are well known. But it is a controversial issue in literature, whether the determination of TgAb should be performed beside or instead of the RT. OBJECTIVE: The study compares the clinical value of the determination of both TgAb and RT with sensitive assays. METHODS: 356 patients (pts) were investigated. The results were compared to the concentration of Tg in the sera of the pts. 288 pts stayed tumor-free, the remaining 68 pts showed a recurrence (local and/or metastatic) of their DTC. We measured Tg (with RT) using an immunoradiometric assay (Tg-IRMA; SELco Tg; Fa. Medipan Diagnostica GmbH) and TgAb using a direct assay (CentAK anti-Tg; also from Fa. Medipan). RESULTS: The prevalence of TgAb, and of disturbed RT respectively, in the whole population of DTC-pts was 7.6%, in the subgroup of tumor-free pts 6.6%, and in the remaining pts with tumor-recurrence 11.8%, respectively 2.0%, 1.7% and 2.9%. In a significantly higher percentage of pts with local/metastatic recurrence, both a positive TgAb (p < 0.001) and a disturbed RT (p < 0.05) were found. 7/68 pts with tumor-recurrence but Tg < 1 ng/ml showed positive TgAb, only 2/7 had a disturbed RT. In this group, no patient with Tg > 1 ng/ml demonstrated either positive TgAb or disturbed RT (p < 0.001 and p < 0.05). CONCLUSION: The determination of TgAb in the follow-up of DTC is necessary, because it supports a suspicion to tumor-recurrence in pts with negative Tg. Also the RT is of great value because of a possibly High dose hook-effect.


Subject(s)
Autoantibodies/blood , Thyroglobulin/immunology , Thyroid Neoplasms/blood , Adenocarcinoma, Follicular/blood , Adenocarcinoma, Follicular/immunology , Adenocarcinoma, Follicular/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Carcinoma, Papillary/blood , Carcinoma, Papillary/immunology , Carcinoma, Papillary/pathology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Staging , Recurrence , Reproducibility of Results , Thyroglobulin/blood , Thyroid Neoplasms/immunology , Thyroid Neoplasms/pathology , Thyrotropin/blood
14.
Mol Biol Cell ; 12(12): 3904-18, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11739789

ABSTRACT

The nucleolus is a ubiquitous, mostly spheroidal nuclear structure of all protein-synthesizing cells, with a well-defined functional compartmentalization. Although a number of nonribosomal proteins involved in ribosome formation have been identified, the elements responsible for the shape and internal architecture of nucleoli are still largely unknown. Here, we report the molecular characterization of a novel protein, NO145, which is a major and specific component of a nucleolar cortical skeleton resistant to high salt buffers. The amino acid sequence of this polypeptide with a SDS-PAGE mobility corresponding to M(r) 145,000 has been deduced from a cDNA clone isolated from a Xenopus laevis ovary expression library and defines a polypeptide of 977 amino acids with a calculated mass of 111 kDa, with partial sequence homology to a synaptonemal complex protein, SCP2. Antibodies specific for this protein have allowed its recognition in immunoblots of karyoskeleton-containing fractions of oocytes from different Xenopus species and have revealed its presence in all stages of oogenesis, followed by a specific and rapid degradation during egg formation. Immunolocalization studies at the light and electron microscopic level have shown that protein NO145 is exclusively located in a cage-like cortical structure around the entire nucleolus, consisting of a meshwork of patches and filaments that dissociates upon reduction of divalent cations. We propose that protein NO145 contributes to the assembly of a karyoskeletal structure specific for the nucleolar cortex of the extrachromosomal nucleoli of Xenopus oocytes, and we discuss the possibility that a similar structure is present in other cells and species.


Subject(s)
Cell Nucleolus/metabolism , Cytoskeletal Proteins/chemistry , Cytoskeletal Proteins/metabolism , Oocytes/cytology , Oocytes/metabolism , Xenopus Proteins/chemistry , Xenopus Proteins/metabolism , Xenopus laevis , Amino Acid Sequence , Animals , Cell Nucleolus/chemistry , Cell Nucleolus/ultrastructure , Cloning, Molecular , Cytoskeletal Proteins/genetics , Cytoskeletal Proteins/ultrastructure , Mass Spectrometry , Microscopy, Confocal , Microscopy, Immunoelectron , Molecular Sequence Data , Oocytes/ultrastructure , Oogenesis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Sequence Homology, Amino Acid , Xenopus Proteins/genetics , Xenopus Proteins/ultrastructure , Xenopus laevis/genetics
15.
Int J Vitam Nutr Res ; 71(5): 293-301, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11725694

ABSTRACT

The effectiveness of a nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogens from the ingested androgens was investigated in healthy 30- to 59-year old men. Subjects were randomly assigned to consume DION (300 mg androstenedione, 150 mg dehydroepiandrosterone, 540 mg saw palmetto, 300 mg indole-3-carbinol, 625 mg chrysin, and 750 mg Tribulus terrestris per day; n = 28) or placebo (n = 27) for 28 days. Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured before and throughout the 4-week supplementation period. Serum concentrations of total testosterone and PSA were unchanged by supplementation. DION increased (p < 0.05) serum androstenedione (342%), free testosterone (38%), dihydrotestosterone (71%), and estradiol (103%) concentrations. Serum HDL-C concentrations were reduced by 5.0 mg/dL in DION (p < 0.05). Increases in serum free testosterone (r2 = 0.01), androstenedione (r2 = 0.01), dihydrotestosterone (r2 = 0.03), or estradiol (r2 = 0.07) concentrations in DION were not related to age. While the ingestion of androstenedione combined with herbal products increased serum free testosterone concentrations in older men, these herbal products did not prevent the conversion of ingested androstenedione to estradiol and dihydrotestosterone.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Androstenedione/therapeutic use , Dehydroepiandrosterone/therapeutic use , Dietary Supplements , Gonadal Steroid Hormones/blood , Phytotherapy , Plant Preparations/therapeutic use , Adult , Age Factors , Analysis of Variance , Double-Blind Method , Humans , Male , Middle Aged , Testosterone/blood
17.
Eur J Cell Biol ; 80(9): 567-79, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11675932

ABSTRACT

Drebrin, an actin-binding 70-kDa protein with an unusually slow SDS-PAGE mobility corresponding to approximately 120 kDa, containing a proline-rich, profilin-binding motif, had originally been reported from neuronal cells, but recently has also been found in diverse other kinds of tissues and cell lines. In biochemical analyses of various cells and tissues, employing gel filtration, sucrose gradient centrifugation, immunoprecipitation and -blotting, we have identified distinct states of soluble drebrin: a approximately 4S monomer, an 8S, ca. 217-kDa putative trimer, a 13S and a > 20S oligomer. In the 8S particles only [35S]methionine-labelled drebrin but no other actin-binding protein has been detected in stoichiometric amounts. By immunofluorescence and immunoelectron microscopy, drebrin-positive material often appeared as "granules" up to 400 nm in diameter, in some cell types clustered near the Golgi apparatus or in lamellipodia, particularly at leading edges, or in dense-packed submembranous masses at tips (acropodia) or ruffles of leading edges, in filopodia and at plaques of adhering junctions. We conclude that these drebrin complexes and drebrin-rich structures allow the build-up and maintenance of high local drebrin concentrations in strategic positions for the regulation of actin filament assembly, thereby contributing to cell motility and morphology, in particular local changes of plasticity and the formation of protrusions.


Subject(s)
Actins/metabolism , Cytoplasmic Granules/metabolism , Neuropeptides/metabolism , Pseudopodia/metabolism , Animals , Cattle , Cell Fractionation , Cell Line , Cytoskeletal Proteins , Humans , Immunohistochemistry , Microscopy, Electron , Neuropeptides/chemistry , Neuropeptides/isolation & purification , Phosphoproteins/metabolism
19.
J Am Coll Nutr ; 20(5): 520-8, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11601567

ABSTRACT

OBJECTIVE: The effectiveness of an androgenic nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogen was investigated in healthy 3 to 58 year old men. DESIGN: Subjects were randomly assigned to consume a nutritional supplement (AND-HB) containing 300-mg androstenediol, 480-mg saw palmetto, 450-mg indole-3-carbinol, 300-mg chrysin, 1,500 mg gamma-linolenic acid and 1.350-mg Tribulus terrestris per day (n = 28), or placebo (n = 27) for 28 days. Subjects were stratified into age groups to represent the fourth (30 year olds, n = 20), fifth (40 year olds, n = 20) and sixth (50 year olds, n = 16) decades of life. MEASUREMENTS: Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate specific antigen and lipid concentrations were measured before supplementation and weekly for four weeks. RESULTS: Basal serum total testosterone, estradiol, and prostate specific antigen (PSA) concentrations were not different between age groups. Basal serum free testosterone concentrations were higher (p < 0.05) in the 30- (70.5 +/- 3.6 pmol/L) than in the 50 year olds (50.8 +/- 4.5 pmol/L). Basal serum androstenedione and dihydrotestosterone (DHT) concentrations were significantly higher in the 30- (for androstenedione and DHT, respectively, 10.4 +/- 0.6 nmol/L and 2198.2 +/- 166.5 pmol/L) than in the 40- (6.8 +/- 0.5 nmol/L and 1736.8 +/- 152.0 pmol/L) or 50 year olds (6.0 +/- 0.7 nmol/L and 1983.7 +/- 147.8 pmol/L). Basal serum hormone concentrations did not differ between the treatment groups. Serum concentrations of total testosterone and PSA were unchanged by supplementation. Ingestion of AND-HB resulted in increased (p < 0.05) serum androstenedione (174%), free testosterone (37%), DHT (57%) and estradiol (86%) throughout the four weeks. There was no relationship between the increases in serum free testosterone, androstenedione, DHT, or estradiol and age (r2 = 0.08, 0.03, 0.05 and 0.02, respectively). Serum HDL-C concentrations were reduced (p < 0.05) by 0.14 mmol/L in AND-HB. CONCLUSIONS: These data indicate that ingestion of androstenediol combined with herbal products does not prevent the formation of estradiol and dihydrotestosterone.


Subject(s)
Anabolic Agents/administration & dosage , Androstenediol/administration & dosage , Dietary Supplements , Estradiol/blood , Testosterone/blood , Administration, Oral , Adult , Age Factors , Androstenedione/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Double-Blind Method , Humans , Male , Middle Aged , Placebos , Prostate-Specific Antigen/blood , Time Factors
20.
Thyroid ; 11(9): 819-24, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11575850

ABSTRACT

A sensitive enzyme-linked immunosorbent assay (ELISA) for measuring serum thyroglobulin (Tg) is described. The assay has a functional sensitivity of 0.03 ng/mL and values obtained in sera from patients with treated differentiated thyroid cancer (DTC; n = 24, 17 of whom showed some evidence of recurrence) and from healthy blood donors (n = 48) were in agreement with those obtained by Tg immunoradiometric assay (IRMA) (functional sensitivity = 0.6 ng/ml) (r = 0.99 and 0.98 for the two groups, respectively). The Tg levels measured by ELISA in 47 of the healthy blood donor sera ranged from 2.3 to 139 ng/ml with 1 serum giving a value of 0.03 ng/mL. The mean +/- standard deviation (SD) Tg concentration for the healthy blood donors was 20.3+/-23 ng/mL. Studies with a recovery test suggest that Tg measurements by ELISA were not always reliable when Tg autoantibodies were present. Analysis of samples from 167 patients treated successfully for DTC (papillary carcinoma, 94; follicular carcinoma, 73) showed that 139 were negative for Tg autoantibodies and of these 106 (76%) had Tg levels measurable by ELISA (0.03 ng/mL or greater). In contrast, only 7 (5%) of these 139 sera had Tg levels measurable by IRMA (0.6 ng/mL or greater). It is possible that this ability to measure Tg simply and easily in most treated DTC patients will have significant advantages for patient care. In particular, the Tg level after initial ablative treatment will usually be measurable rather than undetectable. Furthermore, any increases in serum Tg levels which may herald relapse will be detectable earlier.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Thyroglobulin/blood , Adenocarcinoma, Follicular/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Papillary/blood , Carcinoma, Papillary/therapy , Female , Humans , Immunoradiometric Assay , Male , Middle Aged , Reference Values , Sensitivity and Specificity , Thyroid Neoplasms/blood , Thyroid Neoplasms/therapy
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