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Selected AbstractsRelationship of cigarette smoking to the subgingival microbiotaJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2001A. D. Haffajee Abstract Background: The relationship of cigarette smoking to the composition of the subgingival microbiota is not clear. Some studies indicated higher levels of certain species in smokers, while other studies failed to detect differences in the microbiota between subjects with different smoking histories. Thus, the purpose of the present investigation was to examine the prevalence, proportions and levels of the subgingival species in adult subjects who were current, past or never smokers. Method: 272 adult subjects ranging in age from 20,86 years with at least 20 teeth were recruited for study. Smoking history was obtained using a questionnaire. Clinical measures were taken at 6 sites per tooth at all teeth excluding third molars at a baseline visit. Subgingival plaque samples were taken from the mesial surface of all teeth excluding third molars in each subject at baseline and assayed individually for counts of 29 subgingival species using checkerboard DNA-DNA hybridization. Subjects were subset according to smoking history into never (n=124), past (n=98) and current smokers (n=50). Uni-variate and multi-variate analyses were used to seek associations between smoking category and the counts, proportions and prevalence of subgingival species. Results: Greater differences were observed for the prevalence (% of sites colonized) of the test species in the 3 smoking groups than were observed for counts or proportions of total counts. Members of the orange and red complexes including E. nodatum, F. nucleatum ss vincentii, P. intermedia, P. micros, P. nigrescens, B. forsythus, P. gingivalis and T. denticola were significantly more prevalent in current smokers than in the other 2 groups. The difference in prevalence between smokers and non-smokers was due to greater colonization at sites with pocket depth <4 mm. Stepwise multiple linear regression analysis indicated that combinations of the prevalence of 5 microbial species and pack years accounted for 44% of the variance for mean pocket depth (p<0.000001), while the prevalence of 3 microbial taxa along with age, pack years, current smoking and gender accounted for 31% of the variance in mean attachment level (p<0.000001). The difference in prevalence between current and never smokers of all members of the red complex and 8 of 12 members of the orange complex was significantly greater in the maxilla than in the mandible. Conclusions: The major difference between the subgingival microbiota in subjects with different smoking history was in the prevalence of species rather than counts or proportions. The greater extent of colonization in smokers appeared to be due to greater colonization at pocket depths <4 mm. Differences in colonization patterns between current and never smokers were greater in the maxilla than in the mandible. Zusammenfassung Grundlagen: Die Beziehung zwischen dem Zigarettenrauchen und der Zusammensetzung der subgingivalen Mikroflora ist nicht klar. Einige Studien verweisen auf höhere Titer von bestimmten Spezies bei Rauchern, während andere Studien keine Unterschiede in der Mikroflora zwischen Personen mit unterschiedlichem Raucher- oder Nichtraucherverhalten nachweisen konnten. Daher war der Zweck der vorliegenden Studie die Untersuchung von Prävalenz, Anteil und Titer der subgingivalen Spezies bei erwachsenen Patienten, die zur Zeit, früher oder niemals Raucher waren. Methode: Für die Studie wurden 272 erwachsene Patienten im Alter zwischen 20 und 86 Jahren und wenigstens 20 Zähnen rekrutiert. Die Anamnese des Rauchverhaltens wurde under Verwendung eines Fragebogens durchgeführt. Bei einer Eingangsuntersuchung erfolgten die klinischen Messungen an 6 Stellen pro Zahn bei allen Zähnen außer den dritten Molaren. Bei der Eingangsuntersuchung wurden, bei allen Zähnen außer den dritten Molaren, von den Mesialflächen subgingivale Plaqueproben entnommen. Für die einzelnen Flächen wurde die Anzahl von 29 subgingivalen Spezies mittels Schachbrett-DNA-DNA-Hybridisierung bestimmt. Die Patienten wurden entsprechend der Rauchervorgeschichte in folgende Gruppen eingeteilt: niemals (n=124), früher (n=98) und zur Zeit (n=50). Um Assoziationen zwischen den Rauchkategorien und der Anzahl, dem Anteil und der Prävalenz der subgingivalen Spezies herauszufinden wurden eine uni-variate und multi-variate Analyse verwendet. Ergebnisse: Es wurden größere Unterschiede zwischen den 3 Gruppen hinsichtlich der Prävalenz der Testspezies (% der Taschen die kolonisiert waren) beobachtet als bei der Anzahl oder dem Anteil an der Gesamtzahl der Keime beobachtet wurde. Die Prävalenz der Keime des orangen und roten Komplexes einschließlich. E. nodatum, F. nucleatum ss vincentii, P. intermedia, P. micros, P. nigrescens, B. forsythus, P. gingivalis und T. denticola war bei den aktuellen Rauchern stärker prävalent als in den anderen beiden Gruppen. Die Differenz in der Prävalenz zwischen Rauchern und Nichrauchern wurde verursacht durch eine stärkere Kolonisation in Taschen mit einer Taschentiefe <4 mm. Die schrittweise multiple lineare Regressionsanalyse zeigte, dass Kombinationen der Prävalenz von 5 mikrobiellen Spezies und der Packungsjahre für 44% der Varianz der mittleren Taschentiefe verantwortlich waren (p<0.000001), während die Prävalenz von 3 mikrobiellen Taxa zusammen mit Alter, Packungsjahre, Raucherstatus und Geschlecht für 31% der Varizna im mittleren Attachmentniveau verantwortlich waren (p<0.000001). Die Differenz in der Prävalenz zwischen den aktuellen Rauchern und den die niemals rauchten war für alle Keime der roten Komplexes und 8 von 12 Keimen des orangen Komplexes im Oberkiefer signifikant größer als im Unterkiefer. Schlussfolgerung: Der Hauptunterschied zwischen der subgingivalen Mikroflora bei Patienten mit unterschiedlicher Rauchervorgeschichte lag mehr bei der Prävalenz der Spezies als bei der Anzahl der Keime oder den Anteilen an der Gesamtflora. Das größere Maß an Kolonisation bei den Rauchern schien durch eine stärkere Kolonisation in Taschen <4 mm verursacht zu sein. Differenzen im Kolonisationsmuster zwischen aktuellen Rauchern und Nichtrauchern die niemals rauchten waren im Oberkiefer größer als im Unterkiefer. Résumé Origine, but: La relation entre l'usage de la cigarette et la composition de la microflore sous gingivale n'est pas claire. Certaines études indiquent d'importants niveaux de certaines espèces chez les fumeurs, alors que d'autres études n'arrivent pas à détecter de différences dans la micrflore entre des sujets ayant des histoires tabagiques différentes. Aussi, le propos de cette recherche est d'examiner la prévalence, les proportions et le niveau des espèces sous gingivales chez des sujets adultes fumeurs, anciens fumeurs ou non-fumeurs. Méthodes: 272 sujets adultes, âgès de 20 à 86 ans, ayant au moins 20 dents furent recrutés pour l'étude. L'histoire tabagique fut obtenue à l'aide d'un questionnaire. Des mesures cliniques furent prises sur 6 sites par dents, sur toutes les dents à l'exception des troisièmes molaires lors de la première visite. Des échantillons de plaque sous gingivale étaient prélevés sur la face mésiale de chaque dent à l'exception des troisièmes molaires chez chaque sujet lors de la première visite et individuellement testés pour le comptage de 29 espèces sousgingivales par hybridisation en damier ADN-ADN. Les sujets étaient groupés en sous ensembles en fonction de leur histoire tabagique en non-fumeurs (n=124), ancien fumeurs (n=98), et fumeurs (n=50). Des analyses monovariées et multivariées furent utilisées pour rechercher des associations entre les catégories de fumerus et les comptages, proportions et prévalences des espèces bactériennes. Résultats: De plus grandes différences étaient observées pour la prévalence (% de sites colonisés) des expèces testées dans les 3 groupes, que pour le comptage ou la proportion des comptages totaux. Les membres des complexes orange et rouge dont E. nodatum, F. nucléatum ss vicentii, P. intermedia, P. micros, P. nigrescens, B. forsythus, P. gingivalis, et T. denticolaétait significativement plus prévalent chez les fumeurs que dans les 2 autres groupes. La différence de prévalence entre les fumeurs et les non-fumeurs était due à une plus grande colonisation des sites dont la profondeur de poche était <4 mm. L'analyse par régression linéaire multiple stepwise indiquait que les combinaisons de la prévalence de 5 espèces microbiennes et les paquets-années comptaient pour 44% de la variance pour la moyenne de profondeur de poche (p<0.000001), alors que la prévalence de 3 taxons microbiens avec l'âge, les paquets-années, le tabagisme présent et le sexe comptaient pour 31% de la variance pour le niveau d'attache moyen (p<0.000001). La différence de prévalence entre les fumerus en activité et les non-fumeurs (jamais fumé) de tous les membres du complexe rouge et de 8 des 12 membres du complexe orange était significativement plus élevée au maxillaire qu'à la mandibule. Conclusions: La différence majeure entre les microflores sous gingivales chez les sujets ayant des histoires tabagiques différentes se trouvaient dans la prévalence des expèces plutôt que dans leurs quantité ou leurs proportions. La plus grande importance de colonisation chez les fumerus apparaît être dûe à une colonisation plus grande dans les poches <4 mm. Des différences des caractéristiques de colonisation entre les fumerus actifs et les personnes n'ayant jamais fuméétaient plus importantes au maxillaire qu'à la mandibule. [source] Thoracic Percussion to Determine the Caudal Lung Border in Healthy HorsesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2007Zoltán Bakos Background:The application of equine thoracic percussion has been ignored because of the availability of modern imaging techniques. Ultrasonography is a reliable tool in determining the caudal lung border of horses. The aim of the study was to compare percussion with ultrasonography to determine lung borders in horses. Hypothesis:That thoracic percussion can detect the caudal lung border and that its accuracy is comparable with thoracic ultrasonography. Animals:Fifteen randomly chosen, healthy, Warmblood horses. Methods:The caudal lung border was detected by percussion and ultrasonography at the end of inspiration and expiration on both sides of the thorax. A reference point close to the withers was determined, allowing standardized measurements. The distance between this point and the caudal lung border in different intercostal spaces (ICS) was measured by a tape measure. Results:No significant difference was found between percussional and ultrasonographic results. Greater differences were found between inspiration and expiration by ultrasonography compared with percussion in all intercostal spaces on both sides of the thorax. It was significant (P= .028) in the 12th ICS in the right hemithorax. Conclusions and Clinical Importance: Percussion is a reliable tool to determine the caudal lung border in healthy horses. Differences caused by the displacement of the lung during respiration should be taken into consideration when applying either method. [source] Regulation and Expression of Progesterone Receptor mRNA Isoforms A and B in the Male and Female Rat Hypothalamus and Pituitary Following Oestrogen TreatmentJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2002R. E. M. Scott Abstract Progesterone receptors play a central role in neuroendocrine and behavioural regulation. To gain insight into the sex- and tissue-specific regulation of progesterone receptors, protein binding on a progesterone receptor-oestrogen response element and mRNA levels for progesterone receptor (PR)-A and PR-B were compared between female and male rats following oestradiol benzoate replacement treatment in hypothalamic and pituitary tissue. Both male and female pituitary protein extracts demonstrated an increase in nuclear protein binding activity to a progesterone receptor-oestrogen response element following oestradiol benzoate treatment. However, there was a greater difference in total binding activity seen in the female pituitary extracts compared to male pituitary protein extracts. In both cases, reflecting the binding data, oestradiol benzoate pretreatment led to an increase in pituitary PR-B messenger RNA, although this increase was significantly larger in females than in males. Oestradiol benzoate treatment also led to a significant increase in specific binding of hypothalamic nuclear proteins to the progesterone receptor oestrogen response element from both females and male hypothalamic extracts. In addition, PR-B messenger RNA was induced by oestradiol benzoate treatment in the female rat hypothalamus, under circumstances where no PR-A could be detected. The male also demonstrated an increase in PR-B messenger RNA following oestradiol benzoate treatment, with undetectable levels of PR-A, although to a lesser degree than that seen in the female. The predominance of PR-B over PR-A messenger RNA in rat hypothalamus and pituitary, and the quantitative differences between female and male rats, could both contribute to the greater responsiveness of female rats to progesterone with respect to control over luteinizing hormone release from the pituitary, and lordosis behaviour regulated by hypothalamic neurones. [source] A Comparison of Dental Caries Levels in Two Communities with Different Oral Health Prevention Strategies Stratified in Different Social ClassesJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 1 2007Darius Sagheri PhD Abstract Objectives: To compare dental caries levels of schoolchildren stratified in different social classes whose domestic water supply had been fluoridated since birth (Dublin) with those living in an area where fluoridated salt was available (Freiburg). Methods: A representative, random sample of twelve-year-old children was examined and dental caries was recorded using World Health Organization criteria. Results: A total of 699 twelve-year-old children were examined, 377 were children in Dublin and 322 in Freiburg. In Dublin the mean decayed, missing, and filled permanent teeth (DMFT) was 0.80 and in Freiburg it was 0.69. An examination of the distribution of the DMFT score revealed that its distribution is highly positively skewed. For this reason this study provides summary analyses based on medians and inter-quartile range and nonparametric rank sum tests. In both cities caries levels of children in social class 1 (highest) were considerably lower when compared with the other social classes regardless of the fluoride intervention model used. The caries levels showed a reduced disparity between children in social class 2 (medium) and 3 (lowest) in Dublin compared with those in social class 2 and 3 in Freiburg. Conclusions: The evidence from this study confirmed that water fluoridation has reduced the gap in dental caries experience between medium and lower social classes in Dublin compared with the greater difference in caries experience between the equivalent social classes in Freiburg. The results from this study established the important role of salt fluoridation where water fluoridation is not feasible. [source] Variation in GABRA2 Predicts Drinking Behavior in Project MATCH SubjectsALCOHOLISM, Issue 11 2007Lance O. Bauer Background:, Previous studies demonstrated, and replicated, an association between single nucleotide polymorphisms (SNPs) within the GABRA2 gene and risk for alcohol dependence. The present study examines the association of a GABRA2 SNP with another definition of alcohol involvement and with the effects of psychosocial treatment. Methods:, European-American subjects (n = 812, 73.4% male) provided DNA samples for the analysis. All were participants in Project Matching Alcoholism Treatment to Client Heterogeneity (MATCH), a multi-center randomized clinical trial evaluating the efficacy of 3 types of psychosocial treatment for alcoholism: Cognitive Behavioral Therapy (CBT), Motivational Enhancement Therapy (MET), or twelve-step facilitation (TSF). The daily probabilities of drinking and heavy drinking were estimated during the 12-week treatment and 12-month post-treatment periods. Results:, Subjects homozygous for the allele associated with low risk for alcohol dependence in previous studies had lower daily probabilities of drinking and heavy drinking in the present study. This low-risk allele was also associated with a greater difference in drinking outcomes between the treatments. In addition, it enhanced the relative superiority of TSF over CBT and MET. Population stratification was excluded as a confound using ancestry informative marker analysis. Conclusions:, The assessment of genetic vulnerability may be relevant to studies of the efficacy of psychosocial treatment: GABRA2 genotype modifies the variance in drinking and can therefore moderate power for resolving differences between treatments. [source] Characterisation of indomethacin and nifedipine using variable-temperature solid-state NMRMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2005David C. Apperley Abstract We have characterised the stable polymorphic forms of two drug molecules, indomethacin (1) and nifedipine (2) by 13C CPMAS NMR and the resonances have been assigned. The signal for the CCl carbon of indomethacin has been studied as a function of applied magnetic field, and the observed bandshapes have been simulated. Variable-temperature 1H relaxation measurements of static samples have revealed a T1, minimum for indomethacin at 17.8 °C. The associated activation energy is 38 kJ mol,1. The relevant motion is probably an internal rotation and it is suggested that this involves the COCH3 group. Since the two drug compounds are potential candidates for formulation in the amorphous state, we have examined quench-cooled melts in detail by variable-temperature 13C and 1H NMR. There is a change in slope for and at the glass transition temperature (Tg) for indomethacin, but this occurs a few degrees below Tg for nifedipine, which is perhaps relevant to the lower real-time stability of the amorphous form for the latter compound. Comparison of relaxation time data for the crystalline and amorphous forms of each compound reveals a greater difference for nifedipine than for indomethacin, which again probably relates to real-time stabilities. Recrystallisation of the two drugs has been followed by proton bandshape measurements at higher temperatures. It is shown that, under the conditions of the experiments, recrystallisation of nifedipine can be detected already at 70 °C, whereas this does not occur until 110 °C for indomethacin. The effect of crushing the amorphous samples has been studied by 13C NMR; nifedipine recrystallises but indomethacin does not. The results were supported by DSC, powder XRD, FTIR and solution-state NMR measurements. Copyright © 2005 John Wiley & Sons, Ltd. [source] Seasonal variation in habitat use by salmon, Salmo salar, trout, Salmo trutta and grayling, Thymallus thymallus, in a chalk streamFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2006W. D. RILEY Abstract, A portable multi-point decoder system deployed in a tributary of the River Itchen, a southern English chalk stream, recorded the habitats used by PIT-tagged juvenile salmon, Salmo salar L., trout, Salmo trutta L. and grayling, Thymallus thymallus L., with a high degree of spatial and temporal resolution. The fishes' use of habitat was monitored at 350 locations throughout the stream during September/October 2001 (feeding period) and January/February 2002 (over-wintering period). Salmon parr tended to occupy water 25,55 cm deep with a velocity between 0.4 and 1.0 m s,1. During both autumn and winter, first year salmon (0+ group) were associated with gravel substrate during the daytime and aquatic weed at night. In autumn, 1+ salmon were strongly associated with hard mud substrates during the day and with marginal tree roots at night. In winter, they were located on gravel substrate by day and gravel and mud at night. Trout were associated with a greater range of habitats than salmon, generally occupying deeper and faster water with increasing age. During the autumn, 0+ trout were located along shallow (5,10 cm) and slow (,0.1,0.4 m s,1) margins of the stream, amongst tree roots by day and on silty substrates at night. During winter the 0+ trout occupied silty substrates at all times. As age increased, trout increasingly used coarse substrates; hard mud, gravel and chalk, and weed at night. All age groups of grayling (0+, 1+ and 2+) tended to occupy hard gravel substrate at all times and used deeper and faster water with increasing age. The 1+ and 2+ groups were generally found in water 40,70 cm deep with a velocity between 0.3 and 0.5 ms,1, whilst the 0+ groups showed a preference for shallower water with reduced velocity at night, particularly in the winter. There were greater differences in the habitats used between species and age groups than between the autumn and winter periods, and the distribution of fish was more strongly influenced by substrate type than water depth or velocity. The results are discussed in relation to the habitat requirements of mixed salmonid populations and habitat management. [source] External validation of a risk group defined by recursive partitioning analysis in patients with head and neck carcinoma treated with surgery and postoperative radiotherapyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2007Xavier León MD Abstract Background: Several clinical trials have proved that concurrent chemoradiotherapy is more efficacious than radiotherapy alone among high-risk patients with head and neck squamous cell carcinoma (HNSCC) who undergo surgery. A risk-group classification defined according to a recursive partitioning analysis (RPA) for these patients has been recently proposed. The objective of the present study was to carry out an external validation of this RPA-derived classification system. Methods: A retrospective study of 442 HNSCC patients treated with surgery and postoperative radiotherapy was conducted. The external validity of the RPA-derived classification system was assessed, and its ability to stage patients and to predict locoregional control of the disease was compared with the TNM system. Results: The RPA-derived classification system succeeded in obtaining a monotonic prognosis gradient in locoregional control of the disease with increasing stage, and achieved greater differences in survival between stages than the TNM and pTNM classifications. Besides, the RPA method had a better homogeneity of the categories included in each stage, and in the heterogeneity between stages. Conclusions: The RPA-derived classification system allowed for the clear definition of prognostic groups in surgically treated HNSCC patients, improving the prognostic capacity of the TNM and pTNM classifications. The RPA-derived classification system is a useful tool in the definition of patients who, given a poor prognosis, should be considered candidates to adjuvant chemoradiotherapy. © 2007 Wiley Periodicals, Inc. Head Neck, 2007 [source] Structural MRI biomarkers for preclinical and mild Alzheimer's disease,HUMAN BRAIN MAPPING, Issue 10 2009Christine Fennema-Notestine Abstract Noninvasive MRI biomarkers for Alzheimer's disease (AD) may enable earlier clinical diagnosis and the monitoring of therapeutic effectiveness. To assess potential neuroimaging biomarkers, the Alzheimer's Disease Neuroimaging Initiative is following normal controls (NC) and individuals with mild cognitive impairment (MCI) or AD. We applied high-throughput image analyses procedures to these data to demonstrate the feasibility of detecting subtle structural changes in prodromal AD. Raw DICOM scans (139 NC, 175 MCI, and 84 AD) were downloaded for analysis. Volumetric segmentation and cortical surface reconstruction produced continuous cortical surface maps and region-of-interest (ROI) measures. The MCI cohort was subdivided into single- (SMCI) and multiple-domain MCI (MMCI) based on neuropsychological performance. Repeated measures analyses of covariance were used to examine group and hemispheric effects while controlling for age, sex, and, for volumetric measures, intracranial vault. ROI analyses showed group differences for ventricular, temporal, posterior and rostral anterior cingulate, posterior parietal, and frontal regions. SMCI and NC differed within temporal, rostral posterior cingulate, inferior parietal, precuneus, and caudal midfrontal regions. With MMCI and AD, greater differences were evident in these regions and additional frontal and retrosplenial cortices; evidence for non-AD pathology in MMCI also was suggested. Mesial temporal right-dominant asymmetries were evident and did not interact with diagnosis. Our findings demonstrate that high-throughput methods provide numerous measures to detect subtle effects of prodromal AD, suggesting early and later stages of the preclinical state in this cross-sectional sample. These methods will enable a more complete longitudinal characterization and allow us to identify changes that are predictive of conversion to AD. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] The role of cross-cultural absorptive capacity in the effectiveness of in-country cross-cultural trainingINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2009Ibraiz Tarique Based on the theory of absorptive capacity, this study examines the following question. In the context of cross-cultural training, can the amount of previously accumulated cultural knowledge affect the ability of a trainee to absorb further learning about a new culture, thus enhancing total knowledge and presumably cross-cultural adjustment? In-country cross-cultural training was hypothesized to be more effective when the training components are divided and the sessions are distributed over time , resulting in increased cultural knowledge and greater cross-cultural adjustment. Results from an experimental design suggested that in-country cross-cultural training can increase cultural knowledge, when distributed over time. The results also suggested that the training group had greater differences between pre-training and post-training scores on cross-cultural adjustment, but the differences were not statistically different. The results, methodology and conclusions can be generalized to a variety of populations (e.g. international managers and expatriates) and organizations (e.g. multinationals). For international managers and expatriates, the results showed that in-country cross-cultural training, like predeparture cross-cultural training, is also a viable intervention for knowledge acquisition. [source] Domestic Accounting Standards, International Accounting Standards, and the Predictability of EarningsJOURNAL OF ACCOUNTING RESEARCH, Issue 3 2001Hollis Ashbaugh We investigate (1) whether the variation in accounting standards across national boundaries relative to International Accounting Standards (IAS) has an impact on the ability of financial analysts to forecast non-U.S. firms' earnings accurately, and (2) whether analyst forecast accuracy changes after firms adopt IAS. IAS are a set of financial reporting policies that typically require increased disclosure and restrict management's choices of measurement methods relative to the accounting standards of our sample firms' countries of domicile. We develop indexes of differences in countries' accounting disclosure and measurement policies relative to IAS, and document that greater differences in accounting standards relative to IAS are significantly and positively associated with the absolute value of analyst earnings forecast errors. Further, we show that analyst forecast accuracy improves after firms adopt IAS. More specifically, after controlling for changes in the market value of equity, changes in analyst following, and changes in the number of news reports, we find that the convergence in firms' accounting policies brought about by adopting IAS is positively associated with the reduction in analyst forecast errors. [source] Flu: Effect of Vaccine in Elderly Care Home Residents: A Randomized TrialJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2007Fiona Gaughran MD OBJECTIVES: To determine whether assessing seroprotection after influenza vaccine and administering booster vaccination where not achieved reduces hospitalization and death. To estimate the overall seroprotection rate of influenza vaccine. DESIGN: A two-arm, partially blind, randomized, multicenter, parallel-group, controlled trial. SETTING: Twenty-six care homes in three South London boroughs in fall 2004. PARTICIPANTS: Two hundred seventy-seven elderly permanent care home residents meeting eligibility criteria. INTERVENTION: Postvaccination blood samples were randomized to booster evaluation or no booster evaluation (control). If evaluation revealed inadequate seroprotection, a booster vaccine was administered. MEASUREMENTS: Primary outcome was hospitalization to end April 2005; secondary outcomes were death, antibiotic use, and seroprotection. RESULTS: Sixty percent of the controls and 41% of the booster evaluation group responded to routine vaccination. Booster vaccination where indicated increased seroprotection rates in the booster evaluation group to 66%. Treatment groups did not differ in any outcome measures in the intention-to-treat analysis (hospitalization odds ratio=1.02, 95% confidence interval=0.55,1.87). There was a tendency towards greater differences between groups in the per-protocol analysis than in the intention-to-treat analysis, particularly regarding seroprotection rates. The same effect was observed in the a priori exploratory analysis of residents not seroprotected after routine vaccination alone. CONCLUSION: In a year without circulating influenza, there is no clinical benefit of administering a booster vaccine if routine trivalent vaccination fails to result in seroprotection. Hemagglutination titers rose in two strains postbooster vaccination but fell against the novel strain, Wyoming. The benefit of such a booster strategy when influenza is prevalent thus remains unc ertain. [source] Regional variation of intracortical porosity in the midshaft of the human femur: age and sex differencesJOURNAL OF ANATOMY, Issue 2 2005C. David L. Thomas Abstract This study investigated age and sex differences in patterns of porosity distribution in the midshaft of the human femur. Cross-sections were obtained from 168 individuals from a modern Australian population. The sample comprised 73 females and 95 males, aged between 20 and 97 years. Microradiographs were made of 100-µm sections and pore and bone areas were determined using image processing software. Initially the sample was divided by age: young (20,44 years), middle (45,64 years) and old (65+ years), but it was found that analysis on the basis of the ratio of medullary area to total subperiosteal area gave clearer results. The cortex was divided into three rings radially and into octants circumferentially and the porosity of each segment was calculated. Results showed that a pattern with raised porosity in the posterior and anterolateral regions, and with greater porosity in the inner parts of the cortex, becomes more pronounced with age. In males this pattern develops steadily; in females there are much greater differences between the middle and older groups than earlier in life. The patterns observed are consistent with progressive bone loss occurring along a neutral axis of the cortex where bending stress is lowest and the mechanical advantage of the bone is least. [source] Race/ethnicity and telomere length in the Multi-Ethnic Study of AtherosclerosisAGING CELL, Issue 3 2009Ana V. Diez Roux Summary Telomere length has emerged as a marker of exposure to oxidative stress and aging. Race/ethnic differences in telomere length have been infrequently investigated. Leukocyte telomere length (LTL) was assessed 981 white, black and Hispanic men and women aged 45,84 years participating in the Multi-Ethnic Study of Atherosclerosis. Direct measurement and questionnaire were used to assess covariates. Linear regression was used to estimate associations of LTL with race/ethnicity and age after adjustment for sex, income, education, smoking, physical activity, diet and body mass index. On average blacks and Hispanics had shorter telomeres than whites [adjusted mean differences (standard error) in T/S ratio compared to whites: ,0.041 (0.018) for blacks and ,0.044 (0.018) for Hispanics]. Blacks and Hispanics showed greater differences in telomere length associated with age than whites (adjusted mean differences in T/S ratio per 1 year increase in age ,0.0018, ,0.0047 and ,0.0055 in whites, blacks and Hispanics respectively). Differences in age associations were more pronounced and only statistically significant in women. Race/ethnic differences in LTL may reflect the cumulative burden of differential exposure to oxidative stress (and its predictors) over the lifecourse. [source] Differences in chewing strategies used by edentate peopleJOURNAL OF ORAL REHABILITATION, Issue 9 2002M. R. HEATH Aim:, To examine, in detail, the different masticatory measures that contribute to individual chewing strategies of edentate people. Measures:, Variables relating to displacement and force were derived using a new three dimensional implant force transducer, a mucosal pressure transducer and measurements of mandibular movements. Materials:, Five edentate subjects with conventional upper dentures and lower dentures stabilized on two dental implants. The subjects chewed unilaterally on their preferred chewing side. Seven foods were chewed , almond, fruit pastille, chewing gum and four different meats. Analysis:, The data were analysed by separating each sequence into cycles and ,phases' of cycles for which variables were derived. Results:, As expected, the results showed greater differences between subjects than between foods. From the five subjects, four basic strategies were identified in response to the different foods: one subject primarily modulated force, one subject modulated the number of cycles, two subjects modulated force and the number of cycles and one subject showed little modulation at all. As part of these strategies many striking differences between subjects were observed, e.g. one subject showed little modulation of her ,default' chewing pattern for different foods, yet one subject modulated the number of force and manipulation cycles, the force strategy (forces increasing through sequences) and swallow thresholds. Conclusion:,People appear to develop different strategies to compensate for chewing difficulty by modulating speed, the number of cycles and/or penetration forces. [source] Reflectance spectra of iron meteorites: Implications for spectral identification of their parent bodiesMETEORITICS & PLANETARY SCIENCE, Issue 2 2010Edward A. CLOUTIS Powder spectra are invariably red-sloped over this wavelength interval and have a narrow range of visible albedos (approximately 10,15% at 0.56 ,m). Metal (Fe:Ni) compositional variations have no systematic effect on the powder spectra, increasing grain size results in more red-sloped spectra, and changes in viewing geometry have variable effects on overall reflectance and spectral slope. Roughened metal slab spectra have a wider, and higher, range of visible albedos than powders (22,74% at 0.56 ,m), and are also red-sloped. Smoother slabs exhibit greater differences from iron meteorite powder spectra, exhibiting wider variations in overall reflectance, spectral slopes, and spectral shapes. No unique spectral parameters exist that allow for powder and slab spectra to be fully separated in all cases. Spectral differences between slabs and powders can be used to constrain possible surface properties, and causes of rotational spectral variations, of M-asteroids. The magnitude of spectral variations between M-asteroids and rotational and spectral variability does not necessarily imply a dramatic change in surface properties, as the differences in albedo and/or spectral slope can be accommodated by modest changes in grain size (for powders), small changes in surface roughness (for slabs), or variations in viewing geometry. Since metal powders exhibit much less spectral variability than slabs, M-asteroid spectral variability requires larger changes in either powder properties or viewing geometry than for slabs for a given degree of spectral variation. [source] Mandibular variation among Chinese macaquesAMERICAN JOURNAL OF PRIMATOLOGY, Issue 2 2002Ruliang Pan Abstract In order to clarify the degree to which mandibular variation among Chinese macaques results from functional adaptation and phylogenetic inertia, 13 mandibular variables were analyzed by bivariate and multivariate techniques. The results indicate, not surprisingly, that the main differences in the mandible are associated with size. The study further implies that the variation between species is not closely associated with differences in functional adaptation even though the dietary and related differences are large compared to the situation in other macaques. The great variety in diet and related factors among Chinese macaques may not have yet resulted in a significant variation in the mandible. This may be because their radiation in Asia, though involving considerably greater differences in habitat, climate, and so on, has occurred more recently than for other macaque species in Southeast Asia. Mandibular variation between these species, therefore, is likely to be more closely tied to their immediate prior phylogenetic history. For example, the two stump-tailed macaques are closely similar and are also closely similar to the Assam species. Function in the mandible in these species is quite different. The results, therefore, seem to support the hypothesis that these three macaque species should be placed in a single species-group (sinica) as proposed by Delson [1980], Pan [1998], and Pan et al. [1998]. Am. J. Primatol. 56:99,115, 2002. © 2002 Wiley-Liss, Inc. [source] Sex differences in the prevalence of human birth defects: A population-based study,BIRTH DEFECTS RESEARCH, Issue 5 2001Joseph M. Lary Background Sex differences in the prevalence of several human birth defects have often been reported in the literature, but the extent of sex differences for most birth defects is unknown. To determine the full extent of sex differences in birth defects in a population, we examined population-based data from the Metropolitan Atlanta Congenital Defects Program (MACDP). Methods MACDP records were analyzed for 1968 through 1995. We determined the sex-specific prevalence of all major birth defects, using the total number of live births by sex during these years as the denominator. For each specific defect, we calculated a relative risk with regard to sex on the basis of the ratio of prevalence among males to prevalence among females. Male,female relative risks were also determined for total major birth defects and for several broad categories of defects. Results The overall prevalence of major defects at birth was 3.9% among males and 2.8% among females. All but two of the major categories of birth defects (nervous system defects and endocrine system defects) had a higher prevalence among males. Defects of the sex organs were eight and one-half times more prevalent among males and accounted for about half of the increased risk of birth defects among males relative to females. Urinary tract defects were 62% more prevalent among males, and gastrointestinal tract defects were 55% more prevalent among males. Among specific defect types, twofold or greater differences in prevalence by sex were common. Conclusions Our data indicate that sex differences in the prevalence of specific human birth defects are common, and male infants are at greater risk for birth defects than female infants. Several mechanisms have been proposed to account for these differences. Teratology 64:237,251, 2001. Published 2001 Wiley-Liss, Inc. [source] Pulmonary venous wedge pressure provides a safe and accurate estimate of pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 5 2009Kevin D. Hill MD Abstract Objectives: To compare two methods of pulmonary arterial pressure measurement in children with shunt-dependent pulmonary blood flow. Background: In children with shunt-dependent pulmonary blood flow, direct assessment of pulmonary arterial pressure requires passage of a catheter across the shunt. This can be technically difficult and dangerous. Use of the pulmonary venous wedge pressure offers an alternative but has not been validated in this patient population. Methods: We prospectively studied 18 children with shunt-dependent pulmonary blood flow. Pulmonary venous wedge pressure and directly measured pulmonary arterial pressures were independently assessed by two blinded cardiologists. Results: Directly measured mean pulmonary arterial pressure and pulmonary venous wedge pressure are closely correlated (R2 = 0.80, P < 0.01). Agreement between the two measures is improved at lower mean pressures with greater differences at higher pressures. For 20 of 24 ipsilateral measurements, pulmonary venous wedge pressure was , directly measured pulmonary arterial pressure. Pulmonary venous wedge pressure never underestimated pulmonary arterial pressure by more than 3 mm Hg. Conclusions: Pulmonary venous wedge pressure provides a safe and accurate means of estimating pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow. The slightly lower pressures seen on direct measurement compared with the reverse pulmonary vein may reflect impairment of flow across the shunt by the catheter. © 2009 Wiley-Liss, Inc. [source] Changes of QT dispersion in patients with coronary artery disease dependent on different methods of stress inductionCLINICAL CARDIOLOGY, Issue 3 2000B. Hailer M.D. Abstract Background: Episodes of stress-induced myocardial ischemia in patients with coronary artery disease (CAD) may cause increases of QT dispersion (QTd). Hypothesis: Aim of this study was to analyze the effect of increasing heart rates on QTd and to compare the effect of different methods of stress induction in patients with varying degrees of CAD when estimating QTd. Methods: We studied 58 patients, 22 with prior myocardial infarction (MI), 25 without MI or wall motion disturbances at rest, and 11 patients without evidence of CAD. Prior to coronary angiography, standard 12-lead ECGs were obtained at rest as well as during dynamic exercise and pharmacologic stress using arbutamine simultaneously with echocardiography. QTd was determined at each stress level by subtracting minimal from maximal QT interval duration. Results: QTd values at rest were not consistently higher in the patients with CAD. At maximal heart rate, QTd was statistically significantly higher in patients with CAD with a better discrimination between groups for pharmacologic stress (p < 0.005 for exercise, p < 0.0001 for arbutamine). Patients after MI had higher QTd values under all conditions than did the groups without MI. As in patients with CAD, the values of this group changed more radically as a result of pharmacologic stress. Conclusion: Patients with CAD can be identified on the basis of QTd under stress. These changes were not as marked in patients with MI as their rest values were already increased. Overall, drug-induced stress produced greater differences than dynamic exercise, suggesting that the ischemic threshold might be lower in the former. [source] | |||||||||||||||||||