Home About us Contact
|
Home About us Contact | ||
|
|
||
Increased Age (increased + age)
Selected AbstractsInvestment in Mate Guarding May Compensate for Constraints on Ejaculate Production in the Cricket Gryllodes sigillatusETHOLOGY, Issue 12 2001Philip W. Bateman Although there is a corpus of evidence that females of many taxa are choosy about males, there is less information on how males may react to females of different ,quality' (i.e. potential fecundity). The cricket Gryllodes sigillatus shows distinct mate guarding behaviour. We examined how long males mate guard females of different sizes (reflecting egg load and potential fecundity). We also examined the sperm number in ampullae donated to females of different sizes to see if males make a concomitant difference in investment in ejaculate. We also examined mate-guarding behaviour and ejaculate size of males mated to virgin and nonvirgin females of the same size to see if males equate size with increased age and increased likelihood of mating (increased sperm competition). The results showed that males mate guard larger females for longer but make no difference in ejaculate investment between sizes of female. Males make no significant difference in mate guarding investment or ejaculate investment between virgins and nonvirgins of the same size. There is evidence that other species of crickets do alter their ejaculate depending on the female size and mating history, but have less distinct guarding behaviour. We suggest that mate-guarding investment in G. sigillatus may serve a similar function to that of ejaculate investment in other crickets. [source] The relationship of some negative events and psychological factors to periodontal disease in an adult Swedish population 50 to 80 years of ageJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2002A. Hugoson Abstract Background: Clinical observations and epidemiological studies suggest that experiences of negative life events, especially those manifested as depression, may contribute to an increased susceptibility to periodontal disease. Objective: In the present study, the prevalence of some negative life events and psychological factors and their relation to periodontal disease were investigated. The sample consisted of individuals 50,80 years of age from an extensive cross-sectional epidemiological study performed in 1993 in the city of Jönköping, Sweden. Method: 298 dentate individuals from the Jönköping study were randomly selected. Clinical and radiographic examinations included registration of the number of existing teeth, plaque index, gingival index, pocket depth, and alveolar bone loss. In addition, a questionnaire about socioeconomic status, life events, and psychological and stress-related factors was used. Results: The results revealed that, in addition to the well-documented periodontal disease risk factors such as increased age, oral hygiene status, and smoking, the loss of a spouse (being a widow or widower) and the personality trait of exercising extreme external control were also associated with severe periodontal disease. Conclusion: The findings support recent studies suggesting that traumatic life events such as the loss of a spouse may increase the risk for periodontal disease. Above all, the present results indicate that an individual's ability to cope with stressful stimuli (coping behavior), as measured by the beliefs of locus of control of reinforcements may play a role in the progression of periodontal disease. Zusammenfassung Hintergrund: Klinische Beobachtungen und epidemiologische Studien legen den Schluss nahe, dass negative Ereignisse im Laufe des Lebens, insbesondere solche, die sich in Depression manifestieren, zu einer erhöhten Empfänglichkeit für Parodontitis beitragen. Zielsetzung: Untersuchung der Prävalenz von negativen Ereignissen im Lebenslauf sowie psychologischen Faktoren und deren Beziehung zu Parodontalerkrankungen in einer Population im Alter zwischen 50 und 80 Jahren, die im Rahmen einer extensiven epidemiologischen Querschnittsstudie im Jahre 1993 in der Stadt Jönköping in Schweden untersucht worden war. Material und Methoden: 298 bezahnte Personen wurden randomisiert aus der Jönköping-Studie ausgewählt. Die klinischen und röntgenologischen Untersuchungen umfassten die Erhebung der vorhandenen Zähne, der Plaque Index, Gingival Index, Sondierungstiefen und alveolärem Knochenabbau. Zusätzlich wurden durch Befragung sozioökonomischer Status, Lebensereignisse sowie psychologische und stressbezogene Faktoren erfasst. Ergebnisse: Die Resultate ergaben, dass zusätzlich zu den bekannten Parodontitisrisikofaktoren wit Alter, Mundhygienestatus und Rauchen der Verlust des Ehepartners, also eine Witwe oder ein Witwer zu sein, und das Persönlichkeitsmuster extreme externe Kontrolle auszuüben, mit schwerer Parodontitis assoziiert waren. Schlussfolgerungn: Diese Ergebnisse unterstützen neuere Studien, die Hinweise dafür gegeben haben, dass traumatische Lebensereignisse wie der Verlust eines Ehenpartners das Risiko an Parodontitis zu erkranken erhöhen. Darüber hinaus legen die Ergebnisse den Schluss nahe, dass die individuelle Fähigkeit mit Stress umzugehen (Coping), die in dieser Studie durch die Erfragung der Überzeugung über die Lokalisation der Kontrolle von Verstärkungen erfasst wurde, eine Rolle in der Progression der Parodontitis spielen. Résumé Origine: Des observations cliniques et des études épidémiologiques suggèrent que des évènements négatifs, particulièrement ceux manifestés par une dépression, puisse contribuer à une susceptibilité augmentée à la maladie parodontale. But: Dans cette étude, la prévalence de ces évènements négatifs et les facteurs psychologiques et leurs relations avec la maladie parodontale ont été recherchés. L'échantillon était composé de personnes âgées de 50 à 80 ans issues d'une étude épidémiologique extensive croisée réalisé en 1993 dans la ville de Jonkoping en Suède. Méthode: 298 individus dentés de cette étude furent sélectionnés au hasard. Les examens cliniques et radiographiques comprenaient l'enregistrement du nombre de dents présentes, l'indice de plaque, l'indice gingival, la profondeur de poche et la perte osseuse alvéolaire. De plus, un questionnaire sur le statut socio économique, les évènements de la vie et les facteurs psychologiques en relation avec le stress, fut utilisé. Résultats: Les résultats montrèrent qu'en plus des facteurs de risque bien documentés de maladie parodontale comme l'âge, l'hygiène orale et le tabagisme, la perte d'un époux (que l'on soit veuf ou veuve) et le trait de personnalité de pouvoir exercer un contrôle externe extrême étaient aussi associés avec une maladie parodontale sévère. Conclusion: Ces résultats soutiennent de récentes études qui suggèrent que des évènements traumatisant de la vie quotidienne comme la perte d'un époux puisse augmenter le risque pour la maladie parodontale. Par-dessus tout, ces résultats indiquent que la capacité d'un individu à gérer des stimuli stressants, (comportement gestionnel), mesurés par les convictions de contrôle des renforcements pourrait jouer un rôle dans la progression de la maladie parodontale. [source] Seroprevalence of hepatitis A virus antibodies in Turkish and Moroccan children in Rotterdam,JOURNAL OF MEDICAL VIROLOGY, Issue 2 2004J.H. Richardus Abstract Seasonal fluctuations in hepatitis A have been observed in the Netherlands related to Turkish and Moroccan children after visiting their home countries. This study determined the prevalence and associated factors of hepatitis A virus (HAV) antibodies in Turkish and Moroccan children in Rotterdam. A random sample was taken of children in Rotterdam, aged 5,16 years, of Turkish and Moroccan origin, together with a random sample of native Dutch children aged 5,7 and 14,16 years. Blood was collected by finger prick on filter paper. IgG and IgM anti-HAV was detected by an enzyme-linked immunoassay (EIA). The 319 Turkish, 329 Moroccan, and 248 native Dutch children participated in the study. In Turkish children, IgG anti-HAV increased from 2.2% to 22.2% over the age groups. In Moroccan children, IgG anti-HAV increased from 10.2% to 57.7%. In native Dutch children, 0.8% had IgG anti-HAV in the youngest and 3.1% in the oldest age group. The percentage IgG-positive also having IgM anti-HAV was 21% in Turkish, and 41% in Moroccan children. No IgG-positive native Dutch children had IgM anti-HAV. The prevalence of IgG anti-HAV was associated with increased age, being Moroccan, longer stay in the country of origin before migrating to the Netherlands, and known contact to HAV. The majority of Turkish and Moroccan children aged 4,16 years in Rotterdam are not protected against HAV, but do have a high risk of becoming infected while visiting their native country. Active vaccination against HAV of these children is indicated, with as primary aim their own protection. Prevention of HAV-transmission in the general community should be seen as a secondary benefit. In addition, possible Dutch contacts of nonvaccinated Turkish and Moroccan children, such as day care workers and teachers, should also be vaccinated against HAV. J. Med. Virol. 72:197,202, 2004. © 2004 Wiley-Liss, Inc. [source] Impaired decision making following 49 h of sleep deprivationJOURNAL OF SLEEP RESEARCH, Issue 1 2006WILLIAM D. S. KILLGORE Summary Sleep deprivation reduces regional cerebral metabolism within the prefrontal cortex, the brain region most responsible for higher-order cognitive processes, including judgment and decision making. Accordingly, we hypothesized that two nights of sleep loss would impair decision making quality and lead to increased risk-taking behavior on the Iowa Gambling Task (IGT), which mimics real-world decision making under conditions of uncertainty. Thirty-four healthy participants completed the IGT at rested baseline and again following 49.5 h of sleep deprivation. At baseline, volunteers performed in a manner similar to that seen in most samples of healthy normal individuals, rapidly learning to avoid high-risk decks and selecting more frequently from advantageous low-risk decks as the game progressed. After sleep loss, however, volunteers showed a strikingly different pattern of performance. Relative to rested baseline, sleep-deprived individuals tended to choose more frequently from risky decks as the game progressed, a pattern similar to, though less severe than, previously published reports of patients with lesions to the ventromedial prefrontal cortex. Although risky decision making was not related to participant age when tested at rested baseline, age was negatively correlated with advantageous decision making on the IGT, when tested following sleep deprivation (i.e. older subjects made more risky choices). These findings suggest that cognitive functions known to be mediated by the ventromedial prefrontal cortex, including decision making under conditions of uncertainty, may be particularly vulnerable to sleep loss and that this vulnerability may become more pronounced with increased age. [source] Periodontal disease in research beagle dogs , an epidemiological studyJOURNAL OF SMALL ANIMAL PRACTICE, Issue 12 2008H. E. Kortegaard Objectives: To estimate the prevalence and describe the extent and severity of periodontal disease and associated periodontal parameters in beagle dogs. Methods: A full-mouth, site-specific examination was performed in 98 beagle dogs. Focus was placed on clinical attachment loss, pocket depth and bleeding on probing. Results: The prevalence of clinical attachment loss greater than equal to 1 mm was 20 per cent in the one-year-old dogs, increasing to 84 per cent of the dogs aged more than three years. The number of sites affected with clinical attachment loss greater than equal to 1 mm showed a skewed distribution. The prevalence of clinical attachment loss greater than equal to 4 mm was only seven per cent. A probing pocket depth of 4+ mm was observed in 44 to 81 per cent of the dogs, depending on age. Also, the distribution of the number of deepened pockets/dog was skewed. The teeth most prone to clinical attachment loss greater than equal to 1 mm were the P2, the P3 and the P4 of the maxilla. The teeth most prone to pocket depth greater than equal to 4 mm were the maxillary canines. Clinical Significance: Periodontal disease in terms of clinical attachment loss greater than equal to 1 mm and pocket depth greater than equal to 4 mm is common in beagle dogs, but the major disease burden is carried by only a few dogs. The prevalence increases with increased age but is high already at the age of two years. [source] Acoustic Neuroma in a Private Neurotology Practice: Trends in Demographics and Practice PatternsTHE LARYNGOSCOPE, Issue 11 2007Douglas A. Chen MD Abstract Objectives/Hypothesis: To determine whether changes in demographics and management of patients with acoustic neuromas occurred between the years 1990 and 2005. Study Design: Retrospective chart review. Methods: Charts of all 614 patients with a diagnosis of acoustic neuroma, excluding neurofibromatosis-2, from 1990 through 2005 were reviewed. Age at diagnosis, tumor size, hearing, and initial therapy (observation, stereotactic radiation, or surgical excision) were obtained. Patients were grouped by time period (1990,1994, 1995,2000, 2001,2005). Results: Mean age at diagnosis increased slightly from the middle period (53.4 yr) to the most recent (56.9 yr) (P , .025). The proportion of patients 65 years or older increased from 21% to 29% to 32%, respectively, but the change was not significant. Average tumor size decreased from 1.7 cm initially to 1.4 cm most recently (P , .039). There were no significant changes in hearing. Although surgical excision remains our most common treatment (58.5% in 2001,2005), it is becoming less frequent (>80% in earlier periods) (P , .001). Observation with serial imaging was recommended in 37.3% in 2001 to 2005 as compared with 18.3% and 11.6% in the previous two time periods (P , .001). These changes in initial treatment choices occurred for all age groups and primarily for small tumors. Use of radiation has increased only slightly, to 4.2% in the recent period. Conclusion: Patients with acoustic neuroma are presenting with increased age and smaller tumors compared with 16 years ago. However, these changes cannot totally account for the large change in treatment trends. Technology and demographics are influential in these changes, but other difficult to measure forces, such aspatient influence and patient use of the Internet, are also factors. [source] | |||||||||||||