Metal abundances in hot white dwarfs with signatures of a superionized wind.

About a dozen hot white dwarfs with effective temperatures T eff = 65 000 K - 120 000 K exhibit unusual absorption features in their optical spectra. These objects were tentatively identified as Rydberg lines of ultra-high excited metals in ionization stages v-x, indicating line formation in a dense environment with temperatures near 106 K. Since some features show blueward extensions, it was argued that they stem from a superionized wind. A unique assignment of the lines to particular elements is not possible, although they probably stem from C, N, O, and Ne. To further investigate this phenomenon, we analyzed the ultraviolet spectra available from only three stars of this group; that is, two helium-rich white dwarfs, HE 0504-2408 and HS 0713+3958 with spectral type DO, and a hydrogen-rich white dwarf, HS 2115+1148 with spectral type DAO. We identified light metals (C, N, O, Si, P, and S) with generally subsolar abundances and heavy elements from the iron group (Cr, Mn, Fe, Co, Ni) with solar or oversolar abundance. The abundance patterns are not unusual for hot WDs and can be interpreted as the result of gravitational settling and radiative levitation of elements. As to the origin of the ultra-high ionized metals lines, we discuss the possible presence of a multicomponent radiatively driven wind that is frictionally heated.

Cell-specific cytotoxic effect of pyrazole derivatives on breast cancer cell lines MCF7 and MDA-MB-231.

Pyrazoles and their derivatives belong to a class of compounds that demonstrate a great potential in design of anticancer, antiangiogenic, and antimetastatic drugs. Our earlier studies showed that pyrazole derivatives TOSPYRQUIN and TOSIND diminished viability of colorectal adenocarcinoma cells HT-29. Here we demonstrated for the first time in human mammary gland adenocarcinoma cell lines MCF7 and MDA-MB-231 cells the cytotoxic effects of four pyrazole derivatives: TOSIND, PYRIND, METPYRIND, and DIPYR. Three pyrazoles: PYRIND, METPYRIND, and one novel unpublished derivative DIPYR were tested for the first time in living cells. Viability of MCF7 did not significantly change in the presence of TOSIND but it decreased after 72 hours of treatment with PYRIND (IC-50 39.7 ± 5.8 µM). In the presence of METPYRIND the viability was also diminished, while DIPYR increased MCF7 viability after 24 hours of incubation. The viability of MDA-MB-231 cells was strongly decreased by TOSIND (IC-50 17.7 ± 2.7 µM 72 h), and was not influenced by PYRIND and METPYRIND, while DIPYR increased the viability and stimulated the growth of MDA-MB-231 cells. PYRIND, METPYRIND and DIPYR caused a gradual decrease of caspase-3 and caspase-7 activities in MDA-MB-231 cells and there was no influence of TOSIND on the activity of both caspases. Our results open the way to search for other compounds with pendant pyrazole residues in order to increase their cytotoxic activity; especially with regard to its anti-breast cancer activity. It appears that the pyrazoles synthesized by us diminish cell viability in a cell-specific manner. This observation might be useful in designing 'off-DNA' anticancer drugs, compounds which are not harmful to the healthy cells.

Isotopic composition and identification of the origins of individuals buried in a Neolithic collective grave at Bronocice (southern Poland).

The oxygen present in a human organism comes from numerous sources, but the major factor that causes variation in the isotopic composition of this element in a tissue is available drinking water. The isotopic ratio of oxygen in an organism's tissue, including that found in bones and teeth, reflects the isotopic oxygen composition typical for the area where a given individual developed and lived. Of particular interest with regard to this issue were a series of skeletons from the multiple grave discovered at the Funnel Beaker-Baden settlement at Bronocice (southern Poland). The question therefore arose whether the specimens buried in this grave were part of the local community. The oxygen isotope level was established using apatite isolated from bones or teeth. A femur and root dentine samples taken from permanent teeth were subjected to oxygen isotope analysis. The oxygen isotope level of the site was established on the basis of local water precipitation and measurements taken from the oxygen isotope concentration in apatite samples isolated from the bones of animals co-occurring with the studied human group. It has been found that the oxygen isotope levels in the bones and dentine of almost all the analysed specimens from the excavated site at Bronocice were within the established range for the area's environment, providing evidence for their local origin. Thus, it can be assumed that the analysed group inhabiting the macrosettlement at Bronocice during the Funnel Beaker phase of the Baden culture was most probably of local origin.

Communication: Synperiplanar to antiperiplanar conformation changes as underlying the mechanism of Debye process in supercooled ibuprofen.

In this Communication, we present experimental studies that put new insight into the puzzling nature of the Debye relaxation found in the supercooled liquid state of racemic ibuprofen. The appearance of D-relaxation in the loss spectra of non-hydrogen bonding methylated derivate of ibuprofen has proven that Debye relaxation is related solely with conformational changes of the carboxyl group, termed in this paper as synperiplanar-antiperiplanar. Our studies indicate that the presence of hydrogen bonding capabilities is not here the necessary condition to observe Debye process, however, their occurrence might strongly influence α- and D-relaxations dynamics. Interestingly, the activation energy of the D-process in ibuprofen methyl ester on approaching T(g) was found to be perfectly consistent with that reported for ibuprofen by Affouard and Correia [J. Phys. Chem. B 114, 11397-11402 (2010)] (~39 kJ/mol). Finally, IR measurements suggest that the equilibrium between conformers concentration depends on time and temperature, which might explain why the appearance of D-relaxation in supercooled ibuprofen depends on thermal history of the sample.

Obesity: a systematic review on parental involvement in long-term European childhood weight control interventions with a nutritional focus.

In Europe, about 20% of children are overweight. Focus on parental responsibility is an effective method in weight control interventions in children. In this systematic review we describe the intensity of parental involvement and behaviour change aimed at parents in long-term European childhood weight control interventions. We include European Union studies targeting parents in order to improve children's weight status in multi-component (parental, behaviour change and nutrition) health promotion or lifestyle interventions. The included studies have at least one objectively measured anthropometric outcome in the weight status of the child. Parental involvement was described and categorized based on the intensity of parental involvement and coded using a validated behaviour change taxonomy specific to childhood obesity. Twenty-four studies were analysed. In effective long-term treatment studies, medium and high intensity parental involvement were identified most frequently; whereas in prevention studies low intensity parental involvement was identified most frequently. Parenting skills, generic and specific to lifestyle behaviour, scored frequently in effective weight control interventions. To list parental skills in generic and specific to lifestyle, descriptions of the included studies were summarized. We conclude that intensity of parental involvement and behaviour change techniques are important issues in the effectiveness of long-term childhood weight control interventions.

Differences in oral health behaviour between children from high and children from low SES schools in The Netherlands.

OBJECTIVE: To identify the determinants of dental caries in relation to socio-economic status (SES) within oral health, children's eating habits and parental attitudes towards oral health. BASIC RESEARCH DESIGN: Dental screening data were collected from 6- and 10-year-old schoolchildren from low and high SES schools in The Netherlands in this cross-sectional study. METHODS: The clinical examination was performed by trained dental hygiene students who collected the data on dental caries, dental plaque and duration of brushing. The paper questionnaire completed by the parents included 18 questions about oral health behaviour, eating habits and parental attitudes towards oral health. RESULTS: Two of the six parameters of oral health behaviour were statistically associated with the high caries prevalence in the low SES group (brushing frequency (p = 0.028) and age at the first visit to the dentist (p = 0.044)). High intake of fruit juices and/or soft drinks (p = 0.043) and low calcium intake (p = 0.028) were identified as risk determinants for caries with low SES. All parameters of parental attitudes towards oral health were associated with caries, but not with SES. CONCLUSIONS: This study confirmed that the high caries prevalence in children from low SES schools was associated with oral health behaviour and eating habits. The role of parents was indirectly associated with the occurrence of dental caries. Therefore, it is important to include parents in all intervention programmes in order to reduce the prevalence of caries.

Thyroid cancer among Ukrainians and Belarusians who were children or adolescents at the time of the Chernobyl accident.

Our objective is to assess the regional and temporal dependences of the baseline cases contributing to thyroid cancer incidence among those exposed in childhood or during adolescence in Belarus and Ukraine after the Chernobyl accident. Data are analysed for Kyiv and Sevastopol City and the 25 oblasts (regions) in Ukraine, and for Minsk and Gomel City and the 6 oblasts in Belarus. Average thyroid doses due to the Chernobyl accident were assessed for every birth year in the period from 1968 to 1985. Case data pertain to people who underwent surgical removal of thyroid cancers during the period 1986 to 2001 and who were allocated to their place of residence at the time of the accident. The 35 oblasts/cities were subdivided into an upper, middle and lower group of baseline thyroid cancer incidence. Poisson regressions were performed to estimate age, time and gender dependences of the baseline incidence rates in the three groups. The majority of oblasts/cities with high average doses and the majority of Belarusian oblasts/cities belong to the upper group of baseline thyroid cancer incidence. The baseline in the upper group is estimated to be larger than in the middle group by a factor of 2.3, and by a factor of 4.0 when compared to the lower group. The baseline incidence increases with age and with time since exposure. Estimated baseline incidence rates were found to increase from 1988 to 1999 by factors of three and two for the upper and the two lower groups respectively. The estimated thyroid cancer incidence rates in Belarus and Ukraine, and their dependences on gender and age, are consistent with observed rates found in the larger cancer registries of other countries. In conclusion, the baseline cases are found to contribute about 70% to the thyroid cancer incidence in Ukraine, and about 40% to the incidence in Belarus.

A radioecological model for thyroid dose reconstruction of the Belarus population following the Chernobyl accident.

A radioecological model was developed to estimate thyroid exposures of the Belarus population following the Chernobyl accident. The input of the model includes an extensive data set of the (137)Cs activity per unit area deposited during the Chernobyl accident, the rainfall data for different regions of Belarus, the (131)I/(137)Cs ratio in the deposit and the start of the grazing period in Belarus in April/May 1986. The output of the model is the age-dependent thyroid exposure due to the intake of (131)I with fresh milk. Age-dependent average thyroid doses were assessed for selected regions of Belarus. The maximum thyroid doses were estimated for the inhabitants of Gomel oblast where the highest deposition was observed among the regions considered here. The lowest doses were estimated for Vitebsk oblast with the lowest level of depositions. The mean exposures for the oblasts of Grodno, Minsk, Mogilev and Brest were very similar. The results were compared with estimations of thyroid exposure that were based on (131)I measurements in human thyroids, and they are in good agreement. The model may be used for the assessment of thyroid doses in Belarus for areas where no (131)I measurements are available.

Resolving the structure of ionized helium in the intergalactic medium with the far ultraviolet spectroscopic explorer.

The neutral hydrogen (H I) and ionized helium (He II) absorption in the spectra of quasars are unique probes of structure in the early universe. We present Far-Ultraviolet Spectroscopic Explorer observations of the line of sight to the quasar HE2347-4342 in the 1000 to 1187 angstrom band at a resolving power of 15,000. We resolve the He II Lyman alpha (Lyalpha) absorption as a discrete forest of absorption lines in the redshift range 2.3 to 2.7. About 50 percent of these features have H I counterparts with column densities N(H I) > 10(12.3) per square centimeter that account for most of the observed opacity in He II Lyalpha. The He II to H I column density ratio ranges from 1 to >1000, with an average of approximately 80. Ratios of <100 are consistent with photoionization of the absorbing gas by a hard ionizing spectrum resulting from the integrated light of quasars, but ratios of >100 in many locations indicate additional contributions from starburst galaxies or heavily filtered quasar radiation. The presence of He II Lyalpha absorbers with no H I counterparts indicates that structure is present even in low-density regions, consistent with theoretical predictions of structure formation through gravitational instability.

Redox changes of cytochrome b(559) in the presence of plastoquinones.

We have found that short chain plastoquinones effectively stimulated photoreduction of the low potential form of cytochrome b(559) and were also active in dark oxidation of this cytochrome under anaerobic conditions in Triton X-100-solubilized photosystem II (PSII) particles. It is also shown that molecular oxygen competes considerably with the prenylquinones in cytochrome b(559) oxidation under aerobic conditions, indicating that both molecular oxygen and plastoquinones could be electron acceptors from cytochrome b(559) in PSII preparations. alpha-Tocopherol quinone was not active in the stimulation of cytochrome photoreduction but efficiently oxidized it in the dark. Both the observed photoreduction and dark oxidation of the cytochrome were not sensitive to 3-(3,4-dichlorophenyl)-1, 1-dimethylurea. It was concluded that both quinone-binding sites responsible for the redox changes of cytochrome b(559) are different from either the Q(A) or Q(B) site in PSII and represent new quinone-binding sites in PSII.

Thyroid cancer risk in Belarus after the Chernobyl accident: comparison with external exposures.

Within the time period 1990-1993, childhood thyroid cancer incidence due to the Chernobyl accident increased dramatically in Belarus, especially with regard to the birth cohort January 1, 1971, to May 31, 1986. This rise subsequently slowed down, i.e. during the period 1994-1996. The respective data were analysed and compared with the results of an analysis on the time dependence of thyroid cancer incidence in a pooled cohort of persons who had been exposed during childhood to external radiation with high dose rates. Concerning the period of 5-10 years following exposure, the excess absolute cancer risk per unit thyroid dose in the latter (external) exposure group was found to exceed the one in the Belarus group by a factor of two. This difference, however, is not statistically significant. The age-adjusted average excess absolute risk per unit thyroid dose for the period of 5-50 years following external childhood exposure was found to be 8 female and 14 male cases per 10(4) person-year Gy, which is a factor about 2.5 times higher than for the non-adjusted risk in the pooled cohort, as reported by Ron et al. in 1995. Assessments of future excess thyroid cancer cases due to the Chernobyl accident were done on the basis of the time dependence of thyroid cancer risk following external exposure. The thyroid cancer incidence among the birth cohort considered in Belarus and for a period starting from the cessation of the available observation data (1 January 1997) and extending to 50 years after the Chernobyl accident has been estimated to be about 15,000 cases, with an uncertainty range of 5,000-45,000 cases. According to our calculations, 80% of these cases exceed the baseline risk under enhanced thyroid surveillance.

Childhood exposure due to the Chernobyl accident and thyroid cancer risk in contaminated areas of Belarus and Russia.

The thyroid dose due to 131I releases during the Chernobyl accident was reconstructed for children and adolescents in two cities and 2122 settlements in Belarus, and in one city and 607 settlements in the Bryansk district of the Russian Federation. In this area, which covers the two high contamination spots in the two countries following the accident, data on thyroid cancer incidence during the period 1991-1995 were analysed in the light of possible increased thyroid surveillance. Two methods of risk analysis were applied: Poisson regression with results for the single settlements and Monte Carlo (MC) calculations for results in larger areas or sub-populations. Best estimates of both methods agreed well. Poisson regression estimates of 95% confidence intervals (CIs) were considerably smaller than the MC results, which allow for extra-Poisson uncertainties due to reconstructed doses and the background thyroid cancer incidence. The excess absolute risk per unit thyroid dose (EARPD) for the birth cohort 1971-1985 by the MC analysis was 2.1 (95% CI 1.0-4.5) cases per 10(4) person-year Gy. The point estimate is lower by a factor of two than that observed in a pooled study of thyroid cancer risk after external exposures. The excess relative risk per unit thyroid dose was 23 (95% CI 8.6-82) Gy(-1). No significant differences between countries or cities and rural areas were found. In the lowest dose group of the settlements with an average thyroid dose of 0.05 Gy the risk was statistically significantly elevated. Dependencies of risks on age-at-exposure and on gender are consistent with findings after external exposures.

Action of an antiserum to alpha-tocoquinone on photosystem II-particle preparations of Nicotiana tabacum.

An antiserum to alpha-tocoquinone was prepared by immunization of rabbits. Immunization was obtained by injection of a conjugate consisting of the hapten alpha-tocoquinone attached to methylated ovalbumin into the rabbit. The antiserum recognizes the 3,4-dimethyl-p-benzoquinone group of the molecule as well as part of the immediate vicinity to the side chain. This is concluded from the fact that the antibody has some affinity also to plastoquinone. No reaction of the antibody is observed with alpha-tocopherol hydroquinone or alpha-tocopherol. Reaction of the antiserum to alpha-tocoquinone with photosystem II-particle preparations from tobacco affects the functionality of the preparation. Chlorophyll(a)-fluorescence emission is quenched without an alteration of the emission spectrum. Concomitant with this fluorescence quenching, the lifetime of two fluorescence components namely that of a fast and a slower component are shortened. By analogy with the literature the fast component is associated with chlorophyll(a) of the reaction center core and that of the slow component with the antenna system in which the lifetime parameter is shortened by the antibody from 3.42 ns to 1.795 ns. The action on the fast component is less and leads to a shortening of the lifetime parameter from 0.373 ns to only 0.249 ns. The effect is interpreted in terms of an enhancement of linear photosynthetic electron transport possibly due to an inhibition of the cyclic electron transport around PS II. discovered by Gruszecki et al. (1995), Z. Naturforsch. 50c, 61-68.

Influence of the redox state of ubiquinones and plastoquinones on the order of lipid bilayers studied by fluorescence anisotropy of diphenylhexatriene and trimethylammonium diphenylhexatriene.

The measurements of diphenylhexatriene (DPH) and trimethylammonium diphenylhexatriene (TMA-DPH) fluorescence anisotropy in egg yolk lecithin (EYL) and of DPH anisotropy in dipalmitoylphosphatidylcholine (DPPC) liposomes containing different concentrations of oxidized and reduced ubiquinone (UQ) and plastoquinone (PQ) homologues have been performed. All the oxidized UQ homologues strongly induced ordering of EYL membrane structure, whereas in DPPC liposomes, above the phase transition temperature, the most pronounced effect showed UQ-4. PQ-2 and PQ-9 were less effective than the corresponding ubiquinones in this respect. The reduced forms of UQ and PQ homologues increased the order of membrane lipids to a smaller extent than the corresponding quinones both in the interior of the membrane and closer to its surface. Nevertheless, the investigated prenylquinols showed stronger increase in the membrane order than alpha-tocopherol or alpha-tocopherol acetate, which could be connected with binding of prenylquinol head groups to phospholipid molecules by hydrogen bonds. The strong ordering influence of ubiquinones on the membrane structure was attributed to methoxyl groups of the UQ quinone rings.

Restlessness: the anatomy of a neuropsychiatric symptom.

OBJECTIVE: The aim of this paper is to review the literature on restlessness and related syndromes in order to examine the different causes and clinical descriptions, and to present a pathogenetic model that would incorporate its diverse aetiology. METHOD: A literature search was undertaken with restlessness, agitation, akathisia, hyperactivity, fidgetiness and jitteriness as key words. RESULTS: Causes of restlessness are diverse, and its distinction from other descriptions, such as agitation and hyperactivity, is poorly defined in the literature. Detailed descriptions of the syndromes are therefore lacking. The neuroanatomical basis of restlessness may consist of abnormalities in the cortico-subcortical neuronal circuits, the complex regulation of which may explain why different causes often lead to a common end result. CONCLUSIONS: The terms used to describe restlessness and related disorders should be standardised, and the clinical manifestations investigated pedantically. Human and animal studies should investigate the pathophysiology so that intervention can be based on the underlying mechanisms.

Location of ubiquinone homologues in liposome membranes studied by fluorescence anisotropy of diphenyl-hexatriene and trimethylammonium-diphenyl-hexatriene.

The measurements of diphenyl-hexatriene (DPH) and trimethylammonium-diphenyl-hexatriene (TMA-DPH) fluorescence anisotropy in dipalmitoylphosphatidylcholine (DPPC) and egg yolk lecithin (EYL) liposomes containing different concentrations of various ubiquinone (UQ) homologues have been performed. UQ-4 induced the highest DPH anisotropy increase in DPPC liposomes, whereas for higher UQ homologues the anisotropy was lowered with the increase of UQ side-chain length. These differences were less pronounced in EYL liposomes. It was concluded that at a higher content in the membranes (3-4 mol%), the short-chain ubiquinones are arranged parallel to lipid fatty acid chains, whereas long-chain homologues are progressively removed from the lipid acyl chains into the midplane region of the membrane. At the lower (1-2 mol%) concentrations, long-chain quinones seem to be evenly distributed within the membrane, especially in EYL membranes. UQ-10 in EYL liposomes perturbed TMA-DPH to a similar extend as the short-chain ubiquinones indicating that UQ-10 penetrates the interface regions of the membrane where its redox reactions occur. The localization and physical state of UQ-10 in native membranes is discussed.

Clozapine-induced neuroleptic malignant syndrome: review and report of new cases.

The published case reports of clozapine-induced neuroleptic malignant syndrome (NMS) are reviewed, to which the authors add three, and possibly four, new cases seen in Australia, occurring in and estimated 1,250 patients exposed to the drug. The review suggests that typical NMS does occur with clozapine and that its incidence may be as common as with the classic neuroleptics. The features of clozapine-induced NMS may be somewhat different, with fewer extrapyramidal side effects and a lower rise in creatine kinase levels. The occurrence of NMS with clozapine raises important issues with regard to our understanding of the pathophysiology of the syndrome.

Neuroleptic-induced respiratory dyskinesia.

Respiratory dyskinesia is a common but under-recognized side effect of chronic neuroleptic administration. It manifests as irregular respiration, dyspnea, grunting or gasping, and abnormal chest or esophageal movements. It occurs almost exclusively in association with other tardive effects of neuroleptics, such as tardive dyskinesia and tardive akathisia. Complications of the disorder include respiratory alkalosis and aspiration pneumonia. The authors describe 5 patients with respiratory dyskinesia whose cases highlight the important clinical features of neuroleptic-induced respiratory dyskinesia and the manner in which some cases may be misdiagnosed. They also review the literature on this syndrome and discuss the likely pathophysiological mechanisms.

Clinical characteristics and predisposing factors in acute drug-induced akathisia.

BACKGROUND: As subtypes of drug-induced akathisia have become accepted and attempts have been made at establishing diagnostic criteria, a prospective study of the clinical features and predisposing factors of acute akathisia is a significant deficiency in the literature. METHODS: One hundred consecutive inpatients with non-organic psychotic disorders, not receiving neuroleptics or other drugs and free of akathisia and related disorders at admission, were assessed for psychiatric status and movement disorders at baseline and daily for 2 weeks, with detailed examinations on days 7 and 14. Multiple operational criteria for akathisia were used. The following risk factors were examined: age, sex, current neuroleptic dose, rate of increment of dose, drug type, duration of illness, past use of neuroleptics, extrapyramidal side effects score, Zung Depression Scale score, Spielberger State Anxiety Inventory score, psychosis score, and smoking. RESULTS: Using a global rating, mild akathisia developed in 41% and moderate-to-severe akathisia in 21%. The symptoms that best discriminated akathisia from non-akathisia were shifting weight from foot to foot or walking on the spot, inability to keep legs still, feelings of inner restlessness, and shifting of body position in the chair. The subjective and objective symptoms loaded on separate factors. Akathisia ratings had low correlations with the anxiety and Zung scores. Receiver operating characteristic analysis suggested a cutoff score of 4 on our 10-item Akathisia Scale as optimal for the diagnosis of akathisia, with a stricter criterion of scores of 2 or more on both the subjective and objective items being more suitable for research diagnosis. The most significant predisposing factors were the extrapyramidal side effects score and current neuroleptic dose and its rate of increment, with lesser contributions from serum iron status and medication type. Predictability was, however, modest. CONCLUSION: Acute akathisia is a common syndrome with well-defined clinical features. Its occurrence can be predicted with only modest accuracy.