One-year Olds Research Articles

Pediatric Vestibular Assessment: Clinical Framework.

Although vestibular deficits can have severe repercussions on the early motor development in children, vestibular assessment in young children has not yet been routinely integrated in clinical practice and clear diagnostic criteria to detect early vestibular deficits are lacking. In young children, specific adjustments of the test protocol are needed, and normative data are age-dependent as the vestibular pathways mature through childhood. Therefore, this study aims to demonstrate the feasibility of an extensive age-dependent vestibular test battery, to provide pediatric normative data with the concurrent age trends, and to offer a clinical framework for pediatric vestibular testing. This normative study included 133 healthy children below the age of 4 years (mean: 22 mo, standard deviation: 12.3 mo, range: 5-47 mo) without history of hearing loss or vestibular symptoms. Children were divided into four age categories: 38 children younger than 1 year old, 37 one-year olds, 33 two-year olds, and 25 three-year olds. Children younger than 3 years of age were examined with the video Head Impulse Test (vHIT) of the horizontal semicircular canals, cervical vestibular evoked myogenic potentials (cVEMP) with bone conduction stimuli, and the rotatory test at 0.16, 0.04, and 0.01 Hz. In 3-year old children, the vHIT of the vertical semicircular canals and ocular vestibular evoked myogenic potentials (oVEMP) using a minishaker were added to the protocol. The horizontal vHIT appeared to be the most feasible test across age categories, except for children younger than 1-year old in which the success rate was the highest for the cVEMP. Success rates of the rotatory test varied the most across age categories. Age trends were found for the vHIT as the mean vestibulo-ocular reflex (VOR) gain increased significantly with age (r = 0.446, p < 0.001). Concerning the cVEMP, a significant increase with age was found for latency P1 (r = 0.420, p < 0.001), rectified interpeak amplitude P1-N1 (r = 0.574, p < 0.001), and averaged electromyographic (EMG) activity (r = 0.430, p < 0.001), whereas age trends for the latency N1 were less pronounced (r = 0.264, p = 0.004). Overall, the response parameters of the rotatory test did not show significant age effects ( p > 0.01), except for the phase at 0.01 Hz (r = 0.578, p < 0.001). Based on the reported success rates and age-dependent normative vestibular data, straightforward cutoff criteria were proposed (vHIT VOR gain < 0.7, cVEMP rectified interpeak amplitude < 1.3, oVEMP interpeak amplitude < 10 µV) with accompanying clinical recommendations to diagnose early vestibular impairment. In this large cohort of typically developing children below the age of 4 years, the vHIT and cVEMP were the most feasible vestibular tests. Moreover, the age-dependent normative vestibular data could specify age trends in this group of young children. Finally, based on the current results and clinical experience of more than ten years at the Ghent University Hospital (Belgium), a clinical framework to diagnose early vestibular deficits in young patients is proposed.

Exact inference for integrated population modelling.

Integrated population modelling is widely used in statistical ecology. It allows data from population time series and independent surveys to be analysed simultaneously. In classical analysis the time-series likelihood component can be conveniently approximated using Kalman filter methodology. However, the natural way to model systems which have a discrete state space is to use hidden Markov models (HMMs). The proposed method avoids the Kalman filter approximations and Monte Carlo simulations. Subject to possible numerical sensitivity analysis, it is exact, flexible, and allows the use of standard techniques of classical inference. We apply the approach to data on Little owls, where the model is shown to require a one-dimensional state space, and Northern lapwings, with a two-dimensional state space. In the former example the method identifies a parameter redundancy which changes the perception of the data needed to estimate immigration in integrated population modelling. The latter example may be analysed using either first- or second-order HMMs, describing numbers of one-year olds and adults or adults only, respectively. The use of first-order chains is found to be more efficient, mainly due to the smaller number of one-year olds than adults in this application. For the lapwing modelling it is necessary to group the states in order to reduce the large dimension of the state space. Results check with Bayesian and Kalman filter analyses, and avenues for future research are identified.

Objectively confirmed prevalence of sleep-related rhythmic movement disorder in pre-school children

ObjectiveChildhood sleep-related rhythmic movement disorder (RMD) (ie, sleep-related repetitive movements involving large muscle groups) can impair sleep quality, cause local injury, and disturb household members. Previous parental reports indicate prevalence rates in children under three years of age between 5.5 and 67%. We studied the prevalence of RMD with objective home videosomnography. MethodsParents of 707 children having their one-year routine health check (357 male), 740 children having their two-year health check (395 male), and 17 children of unknown age (nine male), were asked if their child showed sleep-related rhythmic movements. If telephone interview confirmed likely RMD, parents completed a standardised clinical questionnaire and three nights of home videosomnography. ResultsAt the one-year health check, 31/707 possible cases of RMD were identified [maximal prevalence: 4.38%; 95% CI (2.81, 5.89)] compared to 11/740 at the two-year check [maximal prevalence: 1.49%, 95% CI (0.61, 2.36)]. Of 42 possible cases, nine had resolved; 14 were uncontactable, or did not wish to participate, and four did not complete the study protocol. In four of 10 remaining one-year olds and four of five remaining two-year olds parental report was objectively confirmed by videosomnography. Minimal prevalence based on objective observation was therefore 0.28% [95% CI (0.08, 1.30)] at one-year check and 0.41% [95% CI (0.08, 1.24)] at two-year check. ConclusionsPrevalence of RMD in a large population of infants and toddlers was lower than previously reported (maximum prevalence 2.87%, minimum prevalence 0.34%). It is important to confirm parental report using objective measures.

Testing three common stocking methods: Differences in smolt size, migration rate and timing of two strains of stocked Atlantic salmon (Salmo salar)

The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were released as fry, half-year olds and one-year olds. Our results indicate that fish released at the fry and half-year stage produce smaller smolts, and migrate later in the year than their counterparts released at one-year of age, for both the Ätran and the Burrishoole populations. While fry had the lowest probability of migration, half-year old releases had greater migration rates than one-year olds of the same strain. Additionally, Ätran fish tended to migrate earlier in the year than Burrishoole fish of the same age. Our findings highlight the variability that exists among individuals and populations due to inherited factors, and emphasize the importance of considering age of fish and time spent in the hatchery when stocking populations in the wild to maximize smolt output.

A Morphological and Histological Characterization of Male Flower in Chestnut (&lt;em&gt;Castanea&lt;/em&gt;) Cultivar 'Yanshanzaofeng'

Chinese chestnut (Castanea mollissima Blume.) is a widely distributed fruit tree and well known for its ecological and economic value. In order to evaluate obstacles to male reproductive in the C. mollissima, a morphological and histological characterization of male flower of chestnut cultivar 'Yanshanzaofeng' were examined by paraffin section technique and scanning electron microscopy. The results showed that male catkins with floral primordia were formed in the buds of one-year olds shoots in later April. Later, a protoderm, ground meristem and a procambium had differentiated in young anthers. Each young anther soon developed to four microsporangia. The anther wall layers developed completely by mid-May and consisted of one-cell-layered epidermis, one-cell-layered endothecium, two or three middle layers and one-cell-layered tapetum. The tapetum was of glandular type. Microspore mother cells underwent meiosis through simultaneous cytokinesis in later May and gave rise to tetrads of microspores, which were tetrahedrally arranged. Mature pollens contained two cells with three germ pores. Anthers were dehiscent and pollen grains shed by early June. Based our results, we did not find the abnormal male flower in the C. molissma cv 'yanshanzaofeng', indicating that male gametes were fertile and thus was considered as pollenizers.

Physiological and proteomics analyses of Holm oak (Quercus ilex subsp. ballota [Desf.] Samp.) responses to Phytophthora cinnamomi

Phytophthora cinnamomi is one of the agents that trigger the decline syndrome in Quercus spp., this being a serious threat to Mediterranean Holm oak forest sustainability and reforestation programs. Quercus ilex responses to Phytophthora cinnamomi have been studied in one-year olds seedlings from two Andalucía provenances, assessing the physiological water status and photosynthesis-related parameters. Upon inoculation with mycelium a reduction in water content, chlorophyll fluorescence, stomatal conductance and gas exchange was observed along a 90 days post inoculation period in both provenances. The reduction was higher in the most susceptible (SSA) provenance, than in the most tolerant (PCO), being these typical plant responses to drought stress. Leaf protein profiles were analyzed in non-inoculated and inoculated seedlings from the two provenances by using a 2-DE coupled to MS proteomics strategy. Ninety seven proteins changing in abundance in response to the inoculation were successfully identified after MALDI-TOF-TOF analyses. The largest group of variable identified proteins were chloroplasts ones, and they were involved in the photosynthesis, Calvin cycle and carbohydrate metabolism. It was noted that a general tendency was a decrease in the protein abundance as a consequence of the inoculation, being it less accused in the least susceptible, the Northern provenance (PCO), than in the most susceptible, the Southern provenance (SSA). This trend is clearly manifested in photosynthesis, amino acid metabolism and stress/defence proteins. On the contrary, some proteins related to starch biosynthesis, glycolysis and stress related peroxiredoxin showed an increase upon inoculation. These changes in protein abundance were correlated to the estimated physiological parameters and have been frequently observed in plants subjected to drought stress.

Dietary Patterns and Their Changes in Early Childhood

Early childhood is a critical period for shaping and influencing feeding behaviours which have implications for future health. Understanding the food consumption patterns and their shifts over time can provide guidance to health care providers and nutrition specialists who provide nutrition counselling and develop nutrition messages. To examine feeding patterns of 1-5 year old children and their changes with age. Across-sectional questionnaire study designed to obtain information on basic demographic indicators and feeding habits was conducted in Prague and all 13 regions of the Czech Republic. The carers of 1,130 children aged 1 to 5 years were approached in public places. Obtained data were computerized, descriptive statistics and t-tests for food intake frequency by age, breast-feeding status, sex, maternal education, and domicile were calculated. The difference was considered significant when P value was < 0.05. The median duration of breast-feeding of children not breast-fed at the time of the interview was 9 months; 29.5% one-year olds were still breast-fed at the time of the interview. Median number of meals per day was 4 in 1 and 5 year olds and 5 in children 2 to 4 years old. The diet of one-year-olds, albeit with lower fruit and vegetable consumption and low fish consumption, was close to recommendations. The milk and milk products, fruit, vegetable, and poultry intake frequency significantly decreased with age. The meat and grains groups, smoked meat and meat products, sweets, and fried food intake frequency significantly increased with age. Fish consumption remained low. Higher vegetable intake frequency was associated with breast-feeding, maternal education, and female sex. Higher fruit consumption was associated with breast-feeding and living in Prague. Higher meat group intake frequency was associated with male sex. Our data confirm that the dietary habits are formed early in the life. Enhancement of multi-channel delivery of nutrition messages for feeding of toddlers and pre-schoolers and for the improvement of family eating habits are needed.

Variable Variation: Annual and Seasonal Changes in Offspring Sex Ratio in a Bat

Many organisms produce offspring with sex-ratios that deviate from equal numbers of males and females, and numerous adaptive explanations have been proposed. In some species, offspring sex-ratio varies across the reproductive season, again with several explanations as to why this might be adaptive. However, patterns for birds and mammals are inconsistent, and multiple factors are likely involved. Long-term studies on a variety of species may help untangle the complexity. I analyzed a long-term data set on the variation in offspring sex-ratio of the big brown bat, Eptesicus fuscus, a temperate-zone, insectivorous species. Sex ratio varied seasonally, but only in some years. Births early in the season were significantly female biased in years in which parturition occurred relatively early, but not in years with late parturition. Survival of female pups increased with earlier median birth date for the colony, and early-born females were more likely to survive and reproduce as one-year olds, compared to later-born pups. I argue that, due to the unusual timing of reproductive activities in male and female bats that hibernate, producing female offspring early in the year increases their probability of reproducing as one year olds, but this is not the case for male offspring. Thus, mothers that can give birth early in the year, benefit most by producing a female pup. The relative benefit of producing female or male offspring varies depending on the length of the growing season and thus the time available for female pups to reach sexual maturity. This suggests that not only does sex-ratio vary seasonally and among years, depending on the condition of the mother and the environment, but also likely varies geographically due to differences in season length.

Amphibian lipid levels at metamorphosis correlate to post-metamorphic terrestrial survival

In organisms that have complex life cycles, factors in the larval environment may affect both larval and adult traits. For amphibians, the postmetamorphic transition from the aquatic environment to terrestrial habitat may be a period of high juvenile mortality. We hypothesized that lipid stores at metamorphosis may affect an animal's success during this critical transition period. We examined variation in total lipid levels among years and sites in recently metamorphosed individuals of two pond-breeding salamander species, the marbled salamander (Ambystoma opacum) and the mole salamander (A. talpoideum), with limited data for one anuran species (southern leopard frog, Rana sphenocephala). Lipid levels were allometrically related to body size and ranged from 1.9 to 23.8% of body dry mass. The two salamander species differed in lipid allocation patterns, with A. opacum apportioning a higher percentage of total lipid reserves into fat bodies than A. talpoideum. Species differences in lipid allocation patterns may primarily reflect that large metamorphs will mature as one-year olds, and, regardless of species, will alter lipid compartmentalization accordingly. We used mark-recapture data obtained at drift fences encircling breeding ponds for 13 A. opacum cohorts to estimate the proportion of postmetamorphic individuals that survived to breed (age 1-4) and the mean age at first reproduction. Regression models indicated that size-corrected lipid level at metamorphosis (i.e., lipid residuals), and to a lesser extent rainfall following metamorphosis, was positively related to adult survival. Snout-vent length at metamorphosis was negatively related to age at first reproduction. We suggest that lipid stores at metamorphosis are vital to juvenile survival in the months following the transition from aquatic to terrestrial habitat, and that a trade-off shaped by postmetamorphic selection in the terrestrial habitat exists between allocation to energy stores versus structural growth in the larval environment.

Intussusception in children seen at Muhimbili National Hospital, Dar es salaam

To review infants and children with intussusception and assess its magnitude of concern and any seasonal variation in our environment. A retrospective study. Muhimbili National Hospital general paediatric and surgical wards from January 2000 to February 2004. The charts of all infants and children up to the age of 10 years diagnosed to have intussusception were reviewed. Demographic factors evaluated included age, incidence in up to one-year olds, sex, month of presentation to assess seasonal variation, clinical features, methods of diagnosis and management, aetiology and any recurrence. Twenty eight children were diagnosed to have intussusception. Sixteen were males and 12 females (M:F=l .3:1). Of these, 21(75%) were infants (up to the age of one year), nine were boys and 12 were girls( M.F=l:1.3). Incidence rate in this age group was approximately 1: 7557. Most cases presented in January-March(39.3%) and July to September(39.3%). No case was seen in the month of April during the 4-year period. Except in 2002, there has been a male preponderance. The aetiology was mainly idiopathic (85.7%), there were three cases suspected to be due to mesenteric adenitis and one case of intraluminal haemangioma. There were two recurrent cases, one was within a week with no known aetiology. All patients presented with vomiting and abdominal pain/distension. Preceding gastro-enteritis was common. The majority of the cases, 17(60.7%) presented with the classic triad of vomiting, rectal bleeding and abdominal pain/distension. Abdominal mass was often difficult to palpate due to gross or tense abdomen and was only palpated in four cases(14.3%). Air or barium reduction is not done at our institution due to apart from lack of facilities, majority of the children present late, >48 hours from the onset of symptoms and diagnosis was mainly based on clinical symptoms and signs of intestinal obstruction and confirmed with presence of multiple fluid levels on a plain erect abdominal X-ray. All children were then managed by surgery, 11(39.3%) underwent bowel resection. Histopathology reports of those available did not show cause of intussusception. Seven patients died postoperatively, hospital mortality of 25%. The approximate incidence of intussusception in less than one-year olds is 1:7557 in Dar es Salaam. It is a concern in our environment causing considerable morbidity and mortality due to late presentation and efforts should be made to improve sanitation and hygiene, referring health facilities, socio-economic factors and probably look into ways of preventing the problem occurring. Seasonal variation was seen, most cases(78.6%) presenting in the dry season when there is shortage of water in the city.

Linkages between biodiversity loss and human health: a global indicator analysis

The association between health and biodiversity loss was explored by means of regression analysis on a global scale, with control for confounding by socio-economic developments. For this we selected indicators of human health (life expectancy, disability adjusted life expectancy, infant mortality rate and percentage low-birthweight babies), biodiversity (percentage threatened species, current forest as a percentage of original forest, percentage of land highly disturbed by man) and socio-economic development (health expenditure as percentage of GNP, percentage one-year olds immunized, illiteracy rate, GNP per capita and development grade) on a country level. After controlling for relevant socio-economic confounders, both current forest as a percentage of original forest and the percentage of land highly disturbed by human activities had no relationship with one of the health indicators. The logarithm of the percentage threatened species, showed a positive association with life expectancy and disability adjusted life expectancy. The present study was not able to provide any empirical proof of a negative association between loss of biodiversity and human health at the global scale. This does not mean, however, that no such relationship exists, because there may be several reasons for our findings, like possible non-linearity of the relationship, lack of suitable indicators, non-randomness in the sample of countries and the limitations of regression analysis in proving causality.

Incidencia de casos esporádicos de las infecciones intestinales más frecuentes en Castellón

Intestinal infections are highly frequent processes of which solely a part are identified by the epidemiological monitoring systems. This study is aimed at estimating the incidence on the population, by age groups, of the sporadic intestinal infections diagnosed in one healthcare district in Castellón in the year 2000. Based on the routine coprocultures, the basic demographic data for each patient was gathered for calculating the diagnosis and hospitalization rates. For children up to five years of age, the per annum rates were calculation for each microorganism. Campylobacter showed the highest rates (114.5 x 10(5)), followed by rotavirus (94.7) and Salmonella (83.0). Rotavirus is predominant among children under one year of age (3,194 x 10(5)), Campylobacter among those 1-4 year-olds, with a maximum of 3,850 x 10(5) among one-year olds, while Salmonella was predominant among all ages starting as of 5 years of age. The rates for cases hospitalized showed a different pattern, rotavirus ranking first (34.9 x 10(5)), Salmonella (21.7 x 10(5)) and Campylobacter (9.9 x 10(5)). With the exception of Salmonella, there were no outbreaks during the period under study. The predominance of Campylobacter was observed at the expense of the cases among children within the 1-4 age range who were not hospitalized. Up to 4 years of age, the distribution of the germs causing these infections differs every year. A knowledge of the descriptive epidemiology of these infections contributes to the study of the social impact thereof and provides support for delving deeper into some questions that are posed with a view to these diseases and the preventive aspects which can be implemented.

Milk yield and milk composition of Flemish milksheep, Suffolk and Texel ewes and their crossbreds

Milk production (MP) and milk composition (MC) were investigated in 72 ewes of West European sheep breeds: Flemish Milksheep, Suffolk and Texel and their crossbreds, during the first 45 days of lactation and related to postnatal growth of their lambs. Without correction for significant influences, mean daily MP was 1.35 ± 0.47 kg and milk fat, protein and lactose contents were 9.00 ± 1.29, 4.85 ± 0.36, and 5.62 ± 0.25%, respectively. Breed, age of ewe and number of lambs suckled influenced MP significantly ( P < 0.05). Flemish Milksheep ewes had the highest average daily MP (3.33 ± 0.29 kg), while Texel ewes produced the lowest amount (1.10 ± 0.15 kg). The other genotypes had 1.5 kg MP. Two-year old ewes produced 200 g/day more milk than one-year olds. Ewes rearing twins had a higher MP of 400 g/day compared to ewes suckling singles. MC was not significantly influenced by genetic and physiological effects. MP and MC did not vary with circadian rhythms, i.e. a.m. vs. p.m. Significant correlations ( P < 0.0001) indicated that ewes with a high MP in early lactation also continued for a good performance at 45 d postpartum. Early postnatal growth of lambs was dependent on genotype of lamb, birth weight and number of lambs suckled ( P < 0.05). Purebred Milksheep lambs realized a high growth rate (306 ± 37 g/d). Crossbred lambs approximated Milk-sheep, while purebred Texel lambs showed the slowest weight gain. These results were associated with milk uptake and conversion by lambs. Twin lambs grew slower than singles. Regression analyses showed that lambs had to have a chance to suck at least five times/d after 4 h of separation before a good estimation of the realized MP was obtained.

Technical innovations, social stigma and missed profits

How to put on socks, let alone tights, if you cannot reach your legs? Many such problems remain unanswered, despite a large possible market for suitable gadgets. Attempts to direct research towards such problems are hindered by social attitudes (the poor image of the handicapped) and by officialdom (the poor image of existing aids, and the problems of actually obtaining them). That techological solutions can be found is demonstrated by both successes that do exist, and by the commercial successes in developing and marketing products for use in the more socially acceptable contexts - such as walking aids for one-year olds (rather than for 80 year olds). This area provides good examples of research being influenced by social attitudes rather than by underlying needs.

Age-related changes in brain catecholamine responses to a single footshock

—The responses of forebrain and brainstem catecholamine levels to a single footshock were studied in 70-day, one-year, and two-year-old Fischer-344 rats. Brain catecholamine concentrations were assessed 10 minutes after a single 2 second footshock (0, 0.3, or 2.0 mA). In samples taken from non-footshocked rats, only forebrain dopamine concentrations showed a significant age-related decline. However, because the net weights of both the forebrain and the brainstem samples increased significantly with age, the content of forebrain dopamine did not exhibit a significant decline. Both norepinephrine and dopamine levels showed age-related changes in responsiveness to footshock. Norepinephrine concentrations were reduced in both the forebrain and brainstem samples obtained 10 minutes after the high footshock in both the 70-day and one-year-old animals. In two-year-old rats, however, neither forebrain nor brainstem norepinephrine concentrations were altered in response to footshock. Seventy-day-old rats demonstrated significant footshock-induced increases in brainstem dopamine levels, one-year olds showed no appreciable change, and two-year olds demonstrated a non-significant footshock-induced decrease. Thus, both noradrenergic and dopaminergic systems demonstrated age-related changes in their responsiveness to a single brief footshock. These alterations may contribute to the declining ability of the senescent animals to adapt to stressful situations.

Growth, Survival and Reproduction of Plethodon jordani: Trade-Offs between Selective Pressures

Growth and survival of Plethodon jordani were determined from size distributions of large collections made three times per year for five years in the same location. Growth during the first year of life could not be measured because the young only appear above ground one year after being laid as eggs in May. Average growth in snout-vent length was 12.02 mm from May to Oct. during the second year, 1.90 mm from Oct. to the following May and 9.26 mm from May to Oct. of the third year. The increment of growth decreased in all subsequent years. Survival during the second and third years of life was calculated from samples of successive year classes as 0.364 and 0.484, respectively. Some individuals become mature during the summer three years after being laid as eggs. Judged by the condition of ovarian eggs, only one-fourth of the females will mate in Aug. and Sept. and lay eggs when four years old. The same proportion holds for the next year. Individuals six-years-old and older appear to oviposit in alternate years. On the assumption that the annual rate of survival of adults is constant with age, that rate was calculated as 0.81 per year. The calculation was based on the proportion of three-year-olds to those larger. The estimated survival rate permitted matching size and age distributions to obtain a growth curve for those ages not measurable directly. Fecundity was estimated from numbers of large ovarian eggs, corrected for clutch size by using data from P. glutinosus. A combination of the regression of clutch size on snout-vent length and the growth curve made fecundity age-specific. Long-term data revealed a virtually constant population size, permitting the assumption of a stationary life table. Survival during the first year of life would be 0.837 for the net reproductive rate to equal 1.0. Based on the balanced life table, the mean generation time is calculated as 9.8 years. Data on this population from the Balsam Mountains are compared with similar data from the Great Smoky Mountains, where a lower proportion of one-year olds was found. P. glutinosus collected at the same times gave data very similar to Highton's more extensive collections from Maryland and Pennsylvania. The calculated life table for P. jordani is compared with Tilley's for Desmognathus ochrophaeus. The principal differences are in his conclusions that D. ochrophaeus females breed annually, and that there is no statistically significant relation between age and fecundity among mature females. The data for P. jordani cannot be reconciled with these conclusions about D. ochrophaeus. Both competition and predation have been important as selective pressures shaping this life history.