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Biomedical subjects

G Hauser

Publications and source records attributed to G Hauser.

At least 19 recordsLinked to original sources

Body composition characteristics are associated with the bone density of the proximal femur end in middle- and old-aged women and men.

OBJECTIVES: In the present study the associations between bone density of the proximal femur end and weight status, fat distribution patterns (FDI) and body composition parameters i.e. amount of body fat and lean body mass were tested in a sample of old aged women and men. METHODS: In 77 healthy women ranging in age from 60 to 92 years (x=71.8 years) and 62 healthy men ranging in age from 60 to 86 years (x=71.5 years) the bone mineral density (BMD of the proximal femur end and the body composition parameters absolute fat mass, relative fat mass, lean body mass and bone mineral content were estimated by dual energy X-ray absorptiometry. Additionally, the weight status (body mass index, BMI) and the FDI were calculated. The bone density of the proximal femur end was correlated with the absolute fat mass and the lean body mass as well as with the BMI and the FDI. RESULTS: BMD correlated in females significantly positively with parameters of body composition, in males no significant correlations between fat mass (absolute and relative) and BMD as well as BMD/stature was found. Furthermore, it was shown that the weight status (BMI; r(2)=0.13, P<0.0003 in males and r(2)=0.27, P<0.000 in females), and the lean body mass (r(2)=0.21, P<0.001 in males, r(2)=0.36, P<0.004 in females) were associated significantly positively with the BMD of the proximal femur end in both sexes. The absolute fat mass had a significant impact on BMD in the female subsample only (r(2)=0.24, P<0.000). CONCLUSIONS: A lower weight status and a low amount of lean body mass, indicating not only lack of biomechanical forces of the proximal femur end, but also a lack of physical activity can be assumed to be associated increased bone loss and the development of osteoporosis in both sexes. An association between low amount of fat tissue and decreased BMD was especially found in women and may be due to the reduced conversion rates from androgens to estrogens in a low amount of fat tissue.

Absorptiometry, Photon↗

[Significance of body weight status for bone density in the elderly and very old].

Reduced bone density and osteoporosis are significant health problems and contributors to disability and mortality among older women and men. Therefore the decline of bone mineral content (BMC) and bone mineral density (BMD) are aspects of ageing with great medical and social significance. In recent years a low body weight was declared to be an important risk factor for the development of osteoporosis. In the present study the impact of weight status, defined by the categories of the WHO, on BMC of the whole body and BMD of the proximal femur end, determined by dual energy x-ray absorptiometry (DEXA), were studied in 77 female and 62 male probands aged between 60 and 92 years (x = 71.7 yrs). With increasing weight status (BMI categories), BMC and BMD increased significantly (p < 0.001). This was true of both sexes. Even moderate overweight women and men (BMI 25.0-29.99) showed a significantly higher bone density than their normal weight counterparts (BMI < 25.0). In the present study a marked positive impact of body weight on bone density of old-aged women and men could be shown.

Aged↗

Clinical outcome of microsurgical subinguinal varicocelectomy in infertile men.

The present study assesses the clinical outcome of microsurgical subinguinal varicocelectomy in infertile men, especially with regard to sperm count, motility and fertility. Between June 1990 and October 1998, 272 patients had subinguinal microsurgical varicocelectomy operations for clinical varicoceles, and their long-term results were assessed. In nearly all the patients there was a significant improvement in sperm count and sperm motility after 3 and 6 months. Very few complications arose from this procedure. We concluded that microsurgical subinguinal varicocelectomy is an effective treatment for clinical varicoceles in infertile men. The significant improvement in the quality of spermatozoa, the low complication rates and the remarkably high pregnancy rates make this a valuable alternative to in vitro reproduction techniques.

Adolescent↗

Milk consumption, smoking and lead concentration in human hair.

Trace elements in hair samples were examined in 79 medical and sports students in Vienna and 77 biology students in Rome (ages 19-31 years). Lead concentration was determined by inductively coupled plasma mass spectrometry. The effect of smoking on lead levels is confirmed. Those who consume milk and dairy products daily show a lower lead concentration than those who consume them occasionally, both overall and in smokers and non-smokers. The effects of milk consumption and smoking appear to be independent. It seems that smokers may not enjoy the protective effect of milk consumption to the same extent as non smokers.

Adult↗

A qualitative approach to assessing body compartments using bioelectrical variables.

A total of twelve subsamples of healthy European adults (207 males, 208 females) and Ecuadorian school children (300 males, 300 females) were studied with regard to their normal balance of body composition by calculating their bioelectrical values measured by a Phase-Sensitive Impedance Analyzer (BIA 101, Akern s.r.l., Florence, Italy). The method involved bivariate analysis of reactance and phase angle and the associated Bioelectrical nomogram (i.e. 'Biagram') which gives valuable information on the ratio of extra-cellular to body cell masses and confirmed that the vast majority of the subjects were in good physical condition. The few cases of outliers were attributable to slight dehydration after excessive physical activity in the adult sample or to slight overhydration or malnutrition in the child sample. The results of the qualitative approach in various areas of assessment of body composition in healthy and diseased subjects implies its usefulness as a tool in epidemiological studies.

Adult↗

Early evolutionary origin of the neurotrophin receptor family.

Neurotrophins and their Trk receptors play a crucial role in the development and maintenance of the vertebrate nervous system, but to date no component of this signalling system has been found in invertebrates. We describe a molluscan Trk receptor, designated Ltrk, from the snail Lymnaea stagnalis. The full-length sequence of Ltrk reveals most of the characteristics typical of Trk receptors, including highly conserved transmembrane and intracellular tyrosine kinase domains, and a typical extracellular domain of leucine-rich motifs flanked by cysteine clusters. In addition, Ltrk has a unique N-terminal extension and lacks immunoglobulin-like domains. Ltrk is expressed during development in a stage-specific manner, and also in the adult, where its expression is confined to the central nervous system and its associated endocrine tissues. Ltrk has the highest sequence identity with the TrkC mammalian receptor and, when exogenously expressed in fibroblasts or COS cells, binds human NT-3, but not NGF or BDNF, with an affinity of 2.5 nM. These findings support an early evolutionary origin of the Trk family as neuronal receptor tyrosine kinases and suggest that Trk signalling mechanisms may be highly conserved between vertebrates and invertebrates.

Amino Acid Sequence↗

Body composition characteristics after menopause.

The effect of menstrual and reproductive history on body fat development after postmenopause was investigated in 278 healthy females aged between 44 and 67 years (x = 55.8 yrs). The absolute and relative amount of body fat was determined by means of dual energy x-ray absorptiometry. Significant associations between body fat after menopause and age at menarche, age at menopause, and average cycle length were observed. Furthermore the age at first as well as at last birth and the weight gain during pregnancies were related significantly with body fat after menopause. Overweight (BMI > 25.0) during postmenopause was significantly associated with an early menarche, a late menopause, an early first birth and a higher weight gain during pregnancies.

Absorptiometry, Photon↗

Bioelectrical impedance analysis and anthropometry in Ecuadorian children of African ancestry.

In the city of Esmeraldas, north-western coast of Ecuador, height, weight, and body composition of 600 male and female schoolchildren of African ancestry in the age groups four, five and six years were investigated. All the children were apparently healthy without any obvious or reported pathologies and in accordance with data from personal information were assigned to one of two socio-economic classes. The greater values for weight and height shown by children in the higher socio-economic group than in the less well off are compatible with those for more fat and water as obtained by the BIA investigation. Additional information on nutritional, muscular and general health status was obtained from positioning and degree of dispersion of the 'Biagram' ellipses. It seems that both the anthropometric and the bioelectrical impedance methods provide useful information on the differences due to belonging to one or other of the socio-economic groups.

Africa↗

A substance P (neurokinin-1) receptor mutant carboxyl-terminally truncated to resemble a naturally occurring receptor isoform displays enhanced responsiveness and resistance to desensitization.

Two isoforms of the substance P (SP) receptor, differing in the length of the cytoplasmic carboxyl-terminus by approximately 8 kDa, have been detected previously in rat salivary glands and other tissues. The binding and functional properties of these two isoforms have been investigated using full-length (407 amino acids) and carboxyl-terminally truncated (324 amino acids) rat SP receptors transfected stably into Chinese hamster ovary cells. Both the full-length and the truncated receptor bound radiolabeled SP with a similar Kd ( approximately 0.1 nM). The average number of high affinity SP binding sites per cell was 1.0 x 10(5) and 0.3 x 10(5) for the full-length and the truncated SP receptor, respectively. In both cell lines, SP induced a rapid but transient increase in cytosolic calcium concentration ([Ca2+]i), which consisted of the release of Ca2+ from intracellular stores and the influx of extracellular Ca2+. Both components are dependent on phospholipase C activation. Although the full-length and the truncated receptor utilize the same calcium pathways, they differ in their EC50 values (0.28 nM for the full-length; 0.07 nM for the truncated). These differences in responsiveness may be related to the observed differences in receptor desensitization. The truncated receptor, in contrast to the full-length receptor, does not undergo rapid and long-lasting desensitization. Cells possessing the short isoform of the SP receptor would thus be expected to exhibit a prolonged responsiveness.

Animals↗

[Decision to use complementary medicine: fact oriented or irrational?].

PROBLEM AND OBJECTIVE: Complementary medicine is being used to varying extent in all industrial countries. There are incomplete data concerning efficacy, safety and costs of such treatment, while little is known about special features and motivation of those persons who choose complementary medicine. The aim of the study was to ascertain, among patients who use complementary medicine and those who prefer traditional medicine, any differences with regard to sociodemographic, disease-related and psychological characteristics and their life-style. PATIENTS AND METHODS: A total of 419 patients were studied by a standardised interview and questionnaire (168 items) and divided into two groups (group 1: those using conventional treatment [n - 197; 91 women, 106 men; average age 43.2 +/- 16.9 years]; group 2: those preferring complementary medicine [n = 222; 159 women, 63 men; average age 43.2 +/- 15.0 years]). They were recruited from specialist internal medical or generalist medical practice with or without offer of complementary medicine (additional term: natural healing methods). Statistical analysis was with Student's-t-test and the chi(2)-test [correction of gamma-test]. RESULTS: Those patients who chose to be treated by complementary medicine clearly differed from the others with respect to sociodemographic, disease-related and psychological characteristics, as well as life-style. The patient-doctor relationship also differed between the two groups. On average those of group 2 had a higher educational level (higher education: 10.3% in group 1; 15.9 in group 2) and lower risk factors (68.9% nonsmokers in group 1, 77.8% in group 2; alcohol abstinence: 33.2 vs 46.4%). Patients in both groups preferred conventional medicine for serious diseases (cardiac infarct; tumour; AIDS). CONCLUSIONS: In general, those patients who choose complementary medicine have a healthier life-style. As the number of these patients is on the increase. Since as yet the efficacy, risks and costs of complementary medicine have been inadequately investigated, research in this area should be intensified.

Adult↗

Phospholipids inhibit proteolysis of protein kinase C alpha by mM calcium-requiring calpain.

The alpha isoform of protein kinase C (PKC alpha) is rapidly hydrolyzed by mM Ca(2+)-requiring calpain (calcium-activated neutral proteinase) under cell-free conditions (Shea et al, 1994, FEBS Lett. 350:223). In the present study, we demonstrate that this hydrolysis is inhibited by phosphatidyl serine, diacylglycerol, phosphatidyl choline, phosphatidyl inositol, and phosphatidic acid. With the exception of phosphatidic acid, these phospholipids did not directly inhibit calpain activity as evidenced by degradation of [14C]azocasein, suggesting that the nature of inhibition of calpain-mediated PKC alpha degradation is due to an effect of phospholipids on PKC alpha conformation. These findings suggest that m calpain-mediated PKC alpha hydrolysis may be specifically minimized at the plasma membrane, and leave open the possibility that such a mechanism exists in situ. In addition, the unique inhibition of calpain activity by phosphatidic acid suggests the existence of a specific mechanism by which this phospholipid regulates PKC alpha activity.

Calpain↗

Heavy metal concentration in hair of students in Rome.

The levels of five heavy metals (As, Cr, Co, Ni, Pb) in scalp hair were measured in 20 male and 20 female biology students of Rome. Female levels were generally higher except for arsenic and chromium. Sex and smoking resulted most important for heavy metal concentration in hair. Thus smokers show significantly higher levels of lead and slightly increased levels of cadmium, cobalt and nickel.

Adult↗

Heavy metals in human hair samples from Austria and Italy: influence of sex and smoking habits.

Hair samples from 79 young healthy adults from Vienna (Austria) and Rome (Italy) were analyzed for As, Cd, Co, Cr, Ni and Pb by ICP-MS. No differences were found between the two locations except for chromium, which was significantly higher in the Viennese population (P < 0.001). In both cities male hair contained higher arsenic (P < 0.001) and lower cadmium (P < 0.05) levels than female hair, and in Vienna lead concentrations were lower in males (P < 0.05). Striking differences appeared when smokers were compared with non-smokers. Geometric means (micrograms/g) of smokers versus non-smokers were: arsenic 0.081 vs. 0.065, cadmium 0.075 vs. 0.038 (P < 0.05), cobalt 0.025 vs. 0.010 (P < 0.05), chromium 0.84 vs. 0.72 (P < 0.05), lead 3.42 vs. 1.47 (P < 0.001) and nickel 0.64 vs. 0.32 (P < 0.005). Consideration of a large number of biological and behavioural factors minimizes bias inherent in unmatched sample composition.

Adult↗

Complementary chromatographic analysis of free diacylglycerols and potential glycerophospholipid precursors in human SH-SY5Y neuroblastoma cells following incubation with lithium chloride.

We performed detailed chromatographic analyses on the molecular species of the major glycerophospholipids (GPLs) and free sn-1,2-diacylglycerols (DAGs) from SH-SY5Y human neuroblastoma cells following incubation with or without LiCl. For this comparison the inositol, choline, ethanolamine and serine GPLs were dephosphorylated with phospholipase C and the released sn-1,2-diacylglycerols along with the DAGs were subjected to high-temperature GLC on polar and non-polar capillary columns as their trimethylsilyl and tert.-butyl-dimethylsilyl ethers. A 30-min incubation with 10 mM LiCl increased the total amount of human neuroblastoma DAGs by 32-58% (P < 0.05) to 2.6 pmol/micrograms cell protein. This was accompanied by a limited qualitative shift in the molecular species pattern, the most obvious of which was the increase (13%) in the major saturated-polyunsaturated molecular species and the ca. 46% increase in the minor 18:1-18:1 species over control levels. The DAGs originated mainly from the inositol GPLs (IGPLs), as indicated by the high levels of the characteristic 18:0-20:4n6 (18:0-20:3n9) species in both IGPLs and DAGs, and to a lesser extent from the choline GPLs (CGPLs), as indicated by the high proportion in CGPLs of the oligoenoic species, which were largely absent from IGPLs. Alkenylacylglycerols were not detected in DAGs, although they made up some 60% of the total ethanolamine GPLs (EGPLs). No significant changes in the molecular species composition of the cellular GPLs, including IGPLs, were detected after exposure to LiCl.

Brain Neoplasms↗

Brief communication: the skull attributed to Mozart--craniosynostosis or not?

The results of a detailed morphological analysis of the skull attributed to Mozart are presented which refute a recent claim that the skull as well as several of Mozart's portraits show indications of uncomplicated trigonocephaly. These indications according to the present analysis are within the limits of normal variation and derive from retention of part of the long arm of the anterior fontanelle.

Craniosynostoses↗