208 research outputs found
Vocal Learning and Auditory-Vocal Feedback
Vocal learning is usually studied in songbirds and humans, species that can form auditory templates by listening to acoustic models and then learn to vocalize to match the template. Most other species are thought to develop vocalizations without auditory feedback. However, auditory input influences the acoustic structure of vocalizations in a broad distribution of birds and mammals. Vocalizations are dened here as sounds generated by forcing air past vibrating membranes. A vocal motor program may generate vocalizations such as crying or laughter, but auditory feedback may be required for matching precise acoustic features of vocalizations. This chapter discriminates limited vocal learning, which uses auditory input to fine-tune acoustic features of an inherited auditory template, from complex vocal learning, in which novel sounds are learned by matching a learned auditory template. Two or three songbird taxa and four or ve mammalian taxa are known for complex vocal learning. A broader range of mammals converge in the acoustic structure of vocalizations when in socially interacting groups, which qualifies as limited vocal learning. All birds and mammals tested use auditory-vocal feedback to adjust their vocalizations to compensate for the effects of noise, and many species modulate their signals as the costs and benefits of communicating vary. This chapter asks whether some auditory-vocal feedback may have provided neural substrates for the evolution of vocal learning. Progress will require more precise definitions of different forms of vocal learning, broad comparative review of their presence and absence, and behavioral and neurobiological investigations into the mechanisms underlying the skills.PostprintPeer reviewe
Oxpentifylline versus placebo in the treatment of erythropoietin-resistant anaemia: a randomized controlled trial
Background: The main hypothesis of this study is that Oxpentifylline administration will effectively treat erythropoietin-or darbepoietin-resistant anaemia in chronic kidney disease patients
Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.
BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112
Oxidative stress in term small for gestational age neonates born to undernourished mothers: a case control study
BACKGROUND: The objective of this study was to assess the status of oxidative stress in term small for gestational age (SGA) newborn infants born to undernourished mothers by estimating levels of erythrocyte superoxide dismutase (SOD), catalase, reduced glutathione, and serum malondialdehyde (MDA) in cord blood and comparing them to healthy appropriate for gestational age (AGA) controls. This was done in a case control design at a tertiary level teaching hospital. METHODS: We included 20 singleton healthy SGA newborn infants born between 38–40 weeks to undernourished mothers with a) post-pregnancy weight < 50 kg or height < 145 cm AND b) hemoglobin < 8.0 g/dL or serum albumin < 2.5 g/dL. An equal number of age and sex matched AGA newborn infants born to healthy mothers served as Controls. Mothers with other risk factors and newborns with complications during delivery or immediate newborn period were excluded. MDA, SOD, catalase and reduced glutathione were measured in the cord blood of all neonates and compared between the groups (unpaired t test); levels were also correlated to maternal weight, height, hemoglobin, and albumin by both univariate (pearsonian correlation) and multivariate (multiple regression) analysis. RESULTS: The activity of MDA was increased (5.33 ± 0.72 vs 2.55 ± 0.22 nmol/mL; P < 0.0001) while levels of superoxide dismutase (493.6 ± 54.9 vs. 786.8 ± 79.1 U/g Hb; P < 0.0001), catalase (1.48 ± 0.24 vs. 2.31 ± 0.20 U/g Hb; P < 0.0001) and reduced glutathione (2.84 ± 0.37 vs 6.42 ± 0.23 Umol/g Hb, P < 0.0001) were decreased in term SGA born to undernourished mothers as compared to term AGA born to healthy mothers. On univariate analysis, all the markers of oxidative stress correlated significantly with maternal parameters (P < 0.005). On multivariate analysis, maternal albumin and hemoglobin accounted for maximum correlation with the markers of oxidative stress. CONCLUSIONS: Intrauterine malnutrition is associated with significant oxidative stress in small for gestational age neonates born at term to malnourished mothers
Interference between Sentence Processing and Probabilistic Implicit Sequence Learning
During sentence processing we decode the sequential combination of words, phrases or sentences according to previously learned rules. The computational mechanisms and neural correlates of these rules are still much debated. Other key issue is whether sentence processing solely relies on language-specific mechanisms or is it also governed by domain-general principles.In the present study, we investigated the relationship between sentence processing and implicit sequence learning in a dual-task paradigm in which the primary task was a non-linguistic task (Alternating Serial Reaction Time Task for measuring probabilistic implicit sequence learning), while the secondary task were a sentence comprehension task relying on syntactic processing. We used two control conditions: a non-linguistic one (math condition) and a linguistic task (word processing task). Here we show that the sentence processing interfered with the probabilistic implicit sequence learning task, while the other two tasks did not produce a similar effect.Our findings suggest that operations during sentence processing utilize resources underlying non-domain-specific probabilistic procedural learning. Furthermore, it provides a bridge between two competitive frameworks of language processing. It appears that procedural and statistical models of language are not mutually exclusive, particularly for sentence processing. These results show that the implicit procedural system is engaged in sentence processing, but on a mechanism level, language might still be based on statistical computations
The German Young Olympic Athletes' Lifestyle and Health Management Study (GOAL Study): design of a mixed-method study
<p>Abstract</p> <p>Background</p> <p>In order to perform at top levels, elite athletes have to both protect and risk their health at the same time. Adolescent elite athletes have the additional challenge of coping with substantial physical, psychological and social transformations. The contradictory phenomenon of protecting and risking the adolescent athletes' health in sports challenges the development of health promotion and protection strategies. The GOAL Study (German Young Olympic Athletes' Lifestyle and Health Management Study) analyzes the individual and organizational management of health in adolescent elite sports.</p> <p>Methods/design</p> <p>We combine quantitative and qualitative approaches in a mixed-method study. This allows us to gather a broad range of representative information on squad athletes from all Olympic disciplines as well as in-depth information on four selected Olympic disciplines (artistic gymnastics, biathlon, handball and wrestling). Within the quantitative section we attempt to identify the young athletes' health and nutrition behavior, their subjective health state and their lay health representations, health-related social networks, and structures of medical attendance. 1138 national team level athletes born between 1992 and 1995 from 51 Olympic disciplines responded to the questionnaire (response rate: 61,75%). The qualitative section investigates the meaning and relevance of health and nutrition within the athletes' sports specific surroundings, the impact of biographic backgrounds on individual health behavior, and sports specific cultures of health, nutrition and risk. We interviewed 24 athletes and 28 coaching and medical experts, and carried out 14 multi-day participant observations at training sessions and competitions.</p> <p>Conclusions</p> <p>The studies' results will serve as the basis for developing tailored health promotion strategies to be in cooperation with German elite sports associations.</p
Personal factors associated with health-related quality of life in persons with morbid obesity on treatment waiting lists in Norway
Purpose To explore relationships of socio-demographic
variables, health behaviours, environmental characteristics
and personal factors, with physical and mental health
variables in persons with morbid obesity, and to compare
their health-related quality of life (HRQoL) scores with
scores from the general population.
Methods A cross-sectional correlation study design was
used. Data were collected by self-reported questionnaire
from adult patients within the first 2 days of commencement
of a mandatory educational course. Of 185 course
attendees, 142 (76.8%) volunteered to participate in the
study. Valid responses on all items were recorded for 128
participants. HRQoL was measured with the Short Form
12v2 from which physical (PCS) and mental component
summary (MCS) scores were computed. Other standardized
instruments measured regular physical activity, social
support, self-esteem, sense of coherence, self-efficacy and
coping style.
Results Respondents scored lower on all the HRQoL subdomains
compared with norms. Linear regression analyses
showed that personal factors that included self-esteem,
self-efficacy, sense of coherence and coping style
explained 3.6% of the variance in PCS scores and 41.6% in
MCS scores.
Conclusion Personal factors such as self-esteem, sense of
coherence and a high approaching coping style are strongly
related to mental health in obese persons
Bifidobacterium Infantis 35624 Protects Against Salmonella-Induced Reductions in Digestive Enzyme Activity in Mice by Attenuation of the Host Inflammatory Response
OBJECTIVES: Salmonella-induced damage to the small intestine may decrease the villi-associated enzyme activity, causing malabsorption of nutrients and diarrhea, and thus contribute to the symptoms of infection. The objective of this study was to determine the mechanism by which different doses and durations of Salmonella infection and lipopolysaccharide (LPS) affect brush border enzyme activity in the mouse, and to determine if the probiotic Bifidobacterium longum subspecies infantis 35624 could attenuate the intestinal damage.
METHODS: BALB/c mice were challenged with Salmonella enterica serovar Typhimurium UK1 at various doses (10(2)-10(8) colony-forming unit (CFU)) and durations (10(6) CFU for 1-6 days). Mice were also treated with B. longum subsp. infantis 35624 for 2 weeks before and during a 6-day S. Typhimurium challenge (10(6) CFU), or before injection of LPS. The small intestine was assessed for morphological changes, mRNA expression of cytokines, and activity of the brush border enzymes sucrase-isomaltase, maltase, and alkaline phosphatase.
RESULTS: S. Typhimurium infection significantly reduced the activity of all brush border enzymes in a dose- and time-dependent manner (P<0.05). This also occurred following injection of LPS. Pre-treatment with B. longum subsp. infantis 35624 prevented weight loss, protected brush border enzyme activity, reduced the small intestinal damage, and inhibited the increase in interleukin (IL)-10 and IL-8 expression due to Salmonella challenge.
CONCLUSIONS: Salmonella infection reduces the small intestinal brush border enzyme activity in mice, with the level of reduction and associated weight loss increasing with dose and duration of infection. B. longum subsp. infantis 35624 treatment attenuated the effect of Salmonella infection on brush border enzyme activity and weight loss, which may be due to modulation of the host immune response
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