Assessment of determinants for osteoporosis in elderly men.

SUMMARY: The aim of this cross-sectional study was to determine and quantify some determinants associated to low bone mineral density (BMD) in elderly men. This study showed that ageing, a lower body mass index (BMI), a higher blood level of C-terminal cross-linking telopeptides of type I collagen (CTX-1), family history of osteoporosis, and/or fracture and prior fracture were associated with bone mineral density. INTRODUCTION: Our aims were to identify some determinants associated to low bone mineral density in men and to develop a simple algorithm to predict osteoporosis. METHODS: A sample of 1,004 men aged 60 years and older was recruited. Biometrical, serological, clinical, and lifestyle determinants were collected. Univariate, multivariate, and logistic regression analyses were performed. Receiver operating characteristic analysis was used to assess the discriminant performance of the algorithm. RESULTS: In the multiple regression analysis, only age, BMI, CTX-1, and family history of osteoporosis and/or fracture were able to predict the femoral neck T-score. When running the procedure with the total hip T-score, prior fracture also appeared to be significant. With the lumbar spine T-score, only age, BMI, and CTX-1 were retained. The best algorithm was based on age, BMI, family history, and CTX-1. A cut-off point of 0.25 yielded a sensibility of 78%, a specificity of 59% with an area under the curve of 0.73 in the development and validation cohorts. CONCLUSION: Ageing, a lower BMI, higher CTX-1, family history, and prior fracture were associated with T-score. Our algorithm is a simple approach to identify men at risk for osteoporosis.

[Small area analysis of infant mortality in Bielefeld with special consideration of the migration status of parents, 2000-2006]. / Kleinräumige Analyse der Säuglingssterblichkeit in Bielefeld unter besonderer Berücksichtigung des Migrationshintergrundes, 2000-2006.

OBJECTIVE: From 2002 to 2005 the infant mortality rate in the city of Bielefeld has been higher than that of the state of North Rhine Westphalia, in which Bielefeld is located. The 3-year average in Bielefeld was 7.3 vs. 4.7 per 1 000 live births in the period 2002-2004. The aim of our study was to examine the causes of the elevated infant mortality in Bielefeld. METHODS: We conducted a small area analysis and an analysis of the migration status of parents and children in the context of infant mortality. We collected data from death certificates stored at the health office of Bielefeld and coded the cause of death according to ICD-10. We extracted nationality and country of birth from the local population registry. RESULTS: The most frequent causes of death were perinatal factors, malformations and sudden infant death syndrome. Three city districts with a high proportion of population groups with specific sociological risks had an elevated infant mortality. Among infants of migrants, malformations were a more common cause of death (40% of all deaths) than among those without migration background. Perinatal causes were less common among infants with a migration background than without one (42% vs. 54%. of deaths). The authors question whether or not a cause-effect relationship exists here. CONCLUSIONS: The infant mortality rate and the proportion of low birth-weight infants are associated with the social status. Thus, infant mortality is not distributed evenly within a city, either in geographic or in sociological terms. Conversely, statistics about infant mortality define focal points which can be identified and improved. Analysis according to migration background and socio-spatial structures can help to assess health care provided and to initiate targeted interventions, e.g., via local health conferences.

Long-term safety of alpha-lipoic acid (ALA) consumption: A 2-year study.

Alpha-lipoic acid (ALA) (CAS RN 1077-28-7), also referred to as thioctic acid, has been demonstrated to exhibit strong anti-oxidant properties. In order to test the long-term toxicity of ALA, groups of 40-50 male and female, 5-6-week-old, Sprague-Dawley rats were subjected to oral administration of 20, 60, or 180 mg/kg body weight (bw)/day ALA for 24 months. There was no significant difference between control animals and treated animals at 20 or 60 mg/kg bw/day with respect to body weight gain, food consumption, behavioural effects, haematological and clinical chemistry parameters, and gross and histopathological findings. In all treatment groups, mortality was slightly lower as compared to the control. The absolute weights of the heart (high-dose males), thymus (high-dose males), and left adrenal (mid-dose males), liver (high-dose females), and lungs (high-dose females) were decreased in comparison to controls. These changes were of no toxicological significance. The only notable finding in rats of both sexes dosed at 180 mg/kg bw/day was a reduction in food intake relative to the controls and a concomitant decrease in body weight. This decrease in body weight led to significant differences between the control and high-dose rats with respect to the absolute weights of certain organs. However, no gross or histopathological changes were associated with these findings. The no-observed-adverse-effect level (NOAEL) is considered to be 60 mg/kg bw/day.

Safety evaluation of alpha-lipoic acid (ALA).

The safety of the antioxidant alpha-lipoic acid (racemic form) (ALA), also called thioctic acid (CAS RN 1077-28-7) was assessed in acute and subchronic toxicity studies as well as in in vitro and in vivo mutagenicity/genotoxicity studies. ALA was not acutely toxic to rats (LD(50)>2000mg/kg bw, OECD method 425). Administration of 31.6 or 61.9mg ALA/kg bw/day for 4 weeks to male/female Wistar rats did not show any adverse effects. Specifically, there was no significant difference between control and treated animals at 31.6 or 61.9mg ALA/kg bw with regard to body weight gain, feed consumption, animal behaviour, or haematological and clinical chemistry parameters. Only the high-dose of 121mg ALA/kg bw was associated with slight alterations in liver enzymes as well as histopathological effects on the liver and mammary gland. ALA did not possess any mutagenic activity in the Ames assays conducted with various bacterial strains of Salmonella typhimurium. Moreover, there was no evidence of genotoxic activity in a mouse micronucleus assay. The results of these studies support the safety of ALA. The no-observed-adverse-effect level (NOAEL) is considered to be 61.9mg/kg bw/day.

[Health situation of and health service provided for adult migrants--a survey conducted during school admittance examinations]. / Gesundheitliche Lage und Gesundheitsversorgung von erwachsenen Migranten--ein Survey bei der Schuleingangsuntersuchung.

BACKGROUND: In spite of the increasing numbers of migrants in Germany, only few epidemiological studies have been carried out to investigate the health status of ethnic minorities in Germany. Results from national and international studies on the health of immigrants are inconsistent showing either increased or decreased morbidity in relation to native inhabitants. A survey was undertaken to study the self-reported health status, help-seeking behaviour, and health care utilization among immigrants and Germans. METHODS: 565 adults (276 immigrants and 289 Germans, 97% parents) in Bielefeld, Germany, were interviewed while they accompanied children who attended the pre-school medical examinations. In the analysis descriptive statistics and logistic regression models were used. RESULTS: The self-reported general health status of the study population was good for Germans and immigrants. Germans utilized health care facilities and preventive programmes (e. g. screening programmes) more frequently than immigrants. Furthermore, Germans reported higher levels of satisfaction with health care and a higher level of knowledge about several diseases as compared to immigrants. Logistic regression models indicate that neither migration itself (OR = 0.7, 95% CI = 0.4 - 1.1) nor socio-economic factors (OR for low vs. high social level = 1.2, 95% CI = 0.6 - 2.4) were significantly associated with physical diseases among the study population. CONCLUSIONS: We found no indications that immigrants are less healthy compared to Germans. Further investigations are needed to clarify the differences in patterns of health care utilisation and participation in preventive programmes among Germans and ethnic minorities.

Relations of self-esteem concerns, group identification, and self-stereotyping to in-group favoritism.

In 2 studies, the author examined the effect of collective self-esteem (CSE; J. Crocker & R. Luhtanen, 1993) on people's willingness to display in-group favoritism. To test that self-esteem hypothesis, he measured public CSE, rather than private CSE, because the former parallels a threat to social identity, a state believed to motivate in-group favoritism. Furthermore, the author explored whether group identification and self-stereotyping moderated the effect of public CSE on in-group favoritism. The participants were 92 British and Dutch university employees. As expected, participants high in public CSE displayed more in-group favoritism than did those low in public CSE. Moreover, group identification and self-stereotyping appeared to moderate the effect of CSE.

Dimesitylketone O-oxide: spectroscopic characterization, conformation, and reaction modes: OH formation and OH capture.

Dimesitylketone O-oxide 1b was synthesized by photolysis of dimesityldiazomethane dissolved in an oxygen saturated CCl3F solution at 140 K. Conformation and geometry of 1b were determined by comparing measured NMR chemical shifts with the corresponding chemical shifts calculated at the DFT-IGLO level of theory where it had to be considered that the molecule exists in two enantiomeric forms. Measured and calculated 1H chemical shifts agree within 0.1 ppm while the calculated 13C shift of the COO carbon (210.6 ppm) differs by only 0.4 ppm from the measured shift of 211.0 ppm. The two mesityl rings are perpendicular to each other and enclose angles of 40 and 57 degrees with the COO plane. The preferred rearrangement process of 1b is an H migration from one of the ortho-methyl groups to the terminal O atom of the COO unit. The calculated activation enthalpy of this process is 12.7 kcal/mol (B3LYP/cc-pVTZ). In contrast, the activation enthalpy for isomerization to dioxirane is 5 kcal/mol higher. In CCl3F, the activation barrier for the thermal decay was determined to be 13.8 +/- 0.2 kcal/mol and in acetonitrile 13.1 +/- 0.4 kcal/mol. H migration initiates cleavage of the OO bond and the production of an OH and a benzyl radical. Recombination of the latter in the solvent cage leads to the formation of 2-methylhydroxy-pentamethylbenzophenone, while escape of the OH radical from the solvent cage yields a ketone. These results confirm the possibility of OH production from carbonyl oxides in the solution phase.

Self-control and cooperation: different concepts, similar decisions? A question of the right perspective.

Conflicts between an individual's long-term and short-term goals (i.e., self-control conflicts) and conflicts between individual and collective interests (mixed-motive situations) share some interesting features. In this article both types of conflicts are approached from a perspective hypothesis. The hypothesis holds that a decision maker's perspective on his or her decision determines whether either the long-term goals (the collective interests) or the short-term goals (the individual interests) will guide behavior. The hypothesis also implies that factors known to enhance cooperative choices in mixed-motive situations should also facilitate self-control. Three such factors are evaluated: group identification, self-efficacy, and mutual trust. We conclude that the perspective in which choice is considered part of an identifiable series of behaviors is most likely to result in cooperation or self-control.

The ozonolysis of acetylene--a quantum chemical investigation.

The ozonolysis of acetylene was investigated using CCSD(T), CASPT2, and B3LYP-DFT in connection with a 6-311+G(2d,2p) basis set. The reaction is initiated by the formation of a van der Waals complex followed by a [4pi + 2pi] cycloaddition between ozone and acetylene (activation enthalpy DeltaH(a)(298) = 9.6 kcal/mol; experiment, 10.2 kcal/mol), yielding 1,2,3-trioxolene, which rapidly opens to alpha-ketocarbonyl oxide 5. Alternatively, an O atom can be transferred from ozone to acetylene (DeltaH(a)(298) = 15.6 kcal/mol), thus leading to formyl carbene, which can rearrange to oxirene or ketene. The key compound in the ozonolysis of acetylene is 5 because it is the starting point for the isomerization to the corresponding dioxirane 19 (DeltaH(a)(298) = 16.9 kcal/mol), for the cyclization to trioxabicyclo[2.1.0]pentane 10 (DeltaH(a)(298) = 19.5 kcal/mol), for the formation of hydroperoxy ketene 15 (DeltaH(a)(298) = 20.6 kcal/mol), and for the rearrangement to dioxetanone 9 (DeltaH(a)(298) = 23.6 kcal/mol). Compounds 19, 10, 15, and 9 rearrange or decompose with barriers between 13 and 16 kcal/mol to yield as major products formanhydride, glyoxal, formaldehyde, formic acid, and (to a minor extent) glyoxylic acid. Hence, the ozonolysis of acetylene possesses a very complicated reaction mechanism that deserves intensive experimental studies.

The Rotational-Torsional Spectrum of the g'Gg Conformer of Ethylene Glycol: Elucidation of an Unusual Tunneling Path.

The microwave spectrum of the energetically unfavored g'Gg conformer of ethylene glycol (CH(2)OH&bond;CH(2)OH) is reported. This spectrum is dominated by an interconversion geared-type large-amplitude motion during which each OH group in turn forms the intramolecular hydrogen bond. The microwave spectrum has been analyzed with the help of a Watson-type Hamiltonian plus a 1.4-GHz tunneling splitting. The rotational dependence of this tunneling splitting has been examined using an IAM approach and this yielded qualitative information on the tunneling path the molecule uses to interconvert between its two most stable conformers. Unexpectedly, but in agreement with ab initio calculations, when tunneling occurs between the energetically equivalent g'Gg and gGg' conformers, the OH groups are rotated stepwise through 240 degrees in the sense of a flip-flop rather than a concerted rotation and the molecule goes through the more stable g'Ga and aGg' forms. The electronic reasons for preferring a long rather than a short rotational path via a gGg form are discussed using calculated adiabatic vibrational modes. Copyright 2001 Academic Press.

Formation of volatile compounds during heating of spice paprika (Capsicum annuum) powder.

Spice paprika (red pepper; Capsicum annuum) is the most cultivated spice worldwide and is used mainly for its color and pungency. However, current research is also focusing on the flavor as an important parameter. This paper deals with the kinetics of the formation of those volatiles that indicate a decrease in spice paprika quality due to Maillard reaction, hydrolytic reactions, and oxidative degradation reactions of lipids such as fatty acids and carotenoids. Spice paprika volatiles were quantitatively analyzed by means of headspace gas chromatography (HS-GC) and solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS). The kinetics of their formation were investigated, and the respective activation energies determined. Strecker aldehyde, acetone, and methanol formation followed a pseudo-zero-order reaction kinetic, and formation of dimethyl sulfide (DMS) was characterized by a first-order kinetic. The activation energies determined were between 86.3 and 101.8 for the Strecker aldehydes acetaldehyde (AA), 2-methylpropanal (2-MP), 3-methylbutanal (3-MB), and 2-methylbutanal (2-MB), 130.7 for acetone, 114.2 for methanol, and 109.7 kJ/mol for DMS. The amounts of Strecker aldehydes formed were correlated to the concentrations of the corresponding free amino acids present in the samples. The formation of hexanal and 6-methyl-5-hepten-2-one in Capsicum annuum during processing was confirmed, and the formation of beta-ionone was probably described for the first time. During heating, the concentration of hexanal increased rapidly. The formation of 6-methyl-5-hepten-2-one confirms that Capsicum annuum fruits contain lycopene.

4-Oxo-2,3,5,6-tetrafluorocyclohexa-2,5-dienylidene--a highly electrophilic triplet carbene.

The 4-oxocyclohexa-2,5-dienylidenes are an interesting class of highly electrophilic carbenes. We investigated the reactivity of the 2,3,5,6-tetrafluorinated and -tetrachlorinated derivatives 1b and 1c with small molecules under conditions of matrix isolation. The reactions with molecular oxygen and with carbon monoxide produce the expected carbonyl O-oxides and ketenes, respectively. As a result of the extreme electrophilicity of 1b and c both carbenes insert with no or very small activation barriers into H2 or the CH bonds of hydrocarbons. Obviously, spin restrictions for these formally spin-forbidden reactions do not result in substantial thermal activation barriers.

[Reperfusion capacity of the femur head after ischemia--an experimental study]. / Die Reperfusionsfähigkeit des Femurkopfes nach Ischämie--Eine experimentelle Studie.

PURPOSE OF THE STUDY: The aim of this study was to evaluate bone blood flow of the proximal femur during experimentally induced ischemia and to document the ability of epiphyseal and metaphyseal reperfusion. METHODS: 11 pigs (danish landrace) were used to investigate the effect of tamponade by increased joint pressure (Dextran 70) on the perfusion of the femoral head. Additional 8 pigs were used as control. The blood flow in the hip joint was studied by means of the microsphere technique. The flow was determined before, during and after intraarticular pressure increase. With the "radioactive tracer microsphere"-method the blood flow of the epiphysis, metaphysis and proximal femoral corticalis could be measured. RESULTS: In the epiphyseal femoral head the initial blood flow rate, 11.7 ml/min/100 g, was not significant different from that of the control side (11.1 ml/min/100 g). The blood flow decreased in the ischemic phase to 1.8 ml/min/100 g followed by reperfusion to 13.5 ml/min/100 g (p < 0.01). The bone blood flow of reperfusion was not significant different from that of the initial blood flow rate but in 2 cases a "blow out" of the epiphyseal bone blood flow was seen. The proximal femoral metaphysis showed the highest of the measured intraosseous flow rates (17.9 resp. 23.3 ml/min/100 g). During ischemia and reperfusion of the epiphysis bone blood flow of the metaphysis remained the same. The proximal femoral corticalis showed the lowest of the measured intraosseous flow rates. The operated (10.1 ml/min/100 g) and contralateral hip side (11.7 ml/min/100 g) showed no significant differences in the initial blood flow rate. During ischemia and reperfusion the blood flow of the proximal corticalis showed no significant difference to the initial blood flow corresponding to the metaphysis. CONCLUSIONS: Our study demonstrates disturbances of the circulation of different regions of the femoral head during intraarticular pressure increase and following pressure decrease of the growing pig. 2 "blow outs" document a vulnerable proximal epiphysis already after a 6-hour ischemia. Additional minor "bone quality" in cases of certain diseases (kidney transplantation, leukemia) and special administration of drugs (corticosteroids) seem to create an additional vulnerability of the proximal femoral head. The experiment proves to be a reliable model for decreasing the blood flow of the growing epiphysis temporarily and to document the beginning of normal reperfusion. With this model it is possible to examine the vulnerability of the epiphyseal perfusion after different diseases and under the influence of different medication.

Toward a rationalization of the sensitizing potency of substituted p-benzoquinones: reaction of nucleophiles with p-benzoquinones.

MNDO calculations have been carried out for the contact sensitizers 2,6-dimethoxy-1,4-benzoquinone (6) and 2-methoxy-6-methyl-1,4-benzoquinone (10) and for 2,5-dimethoxy-1,4-benzoquinone (7), which is nonallergenic in contrast to thymoquinone (8) (2-methyl-5-isopropyl-1,4-benzoquinone), which is a relatively strong contact allergen. Theoretical results indicate that the conformational flexibility of methoxy groups substituted at the quinone rings influences the electronic properties of these compounds, in particular their reactivity with regard to nucleophiles. According to theory, 6, 10, and 8 should possess a pronounced reactivity toward nucleophiles while 7 should resist nucleophilic attack. Hence, the allergenic capacity of a quinone seems to depend on their binding interactions with nucleophiles such as amino or thio groups of amino acids.