Serum Total Selenium Status in Greek Adults and Its Relation to Age. The ATTICA Study Cohort

The trace element selenium is an essential micronutrient for human health and its low levels in serum are implicated in the pathogenesis of several chronic diseases. Therefore, the determination of total selenium in serum may contribute to the assessment of the health and nutritional status of certain populations. The objective of the present work was to determine total selenium in the serum of 506 healthy volunteers that participated in the ATTICA study. Selenium was determined in serum by using the technique of inductively coupled plasma mass spectrometry. The mean serum selenium concentration was determined to be 91.8 ± 33.7 μg/L (N = 506); 87.6% of women and 88.5% of men had serum selenium concentration below 125 μg/L, the cutoff considered to be required for optimal glutathione peroxidase activity. No association was found between serum selenium levels and the gender of the participants while a significant decline of selenium with age (p < 0.0001) was observed. According to our results, no anthropometric, lifestyle, nutritional, or biochemical indices were able to affect the association between serum selenium and age. This result may indicate that other factors such as selenium distribution as well as retention may be affecting the relationship between serum selenium and age.     

Protein Composition in Relation to Age of Daffodil Leaves

Daffodil foliage leaves were divided into sections along theirlength; the basal sections then contained the youngest, growingregions of the leaves, and the other sections represented progressivelyolder tissue as the leaf apex was approached. Representativeprotein fractions were isolated from some of these sections,and after hydrolysis their amino-acid compositions were compared.Protein from bulb scale leaves was also analysed. Within thefoliage leaf, age did not markedly affect the composition ofthe proteins. Larger differences of composition were found whenthe proteins of the bulb scale, a typical storage tissue, werecompared with those of the foliage leaves. The free amino-acid complements of the different sections ofthe foliage leaves were also compared. Variation of compositionwith leaf age did occur, but no generalizations can be madethat are applicable to all amino-acids.     

Refractive Status at Birth: Its Relation to Newborn Physical Parameters at Birth and Gestational Age

Background

Refractive status at birth is related to gestational age. Preterm babies have myopia which decreases as gestational age increases and term babies are known to be hypermetropic. This study looked at the correlation of refractive status with birth weight in term and preterm babies, and with physical indicators of intra-uterine growth such as the head circumference and length of the baby at birth.

Methods

All babies delivered at St. Stephens Hospital and admitted in the nursery were eligible for the study. Refraction was performed within the first week of life. 0.8% tropicamide with 0.5% phenylephrine was used to achieve cycloplegia and paralysis of accommodation. 599 newborn babies participated in the study. Data pertaining to the right eye is utilized for all the analyses except that for anisometropia where the two eyes were compared. Growth parameters were measured soon after birth. Simple linear regression analysis was performed to see the association of refractive status, (mean spherical equivalent (MSE), astigmatism and anisometropia) with each of the study variables, namely gestation, length, weight and head circumference. Subsequently, multiple linear regression was carried out to identify the independent predictors for each of the outcome parameters.

Results

Simple linear regression showed a significant relation between all 4 study variables and refractive error but in multiple regression only gestational age and weight were related to refractive error. The partial correlation of weight with MSE adjusted for gestation was 0.28 and that of gestation with MSE adjusted for weight was 0.10. Birth weight had a higher correlation to MSE than gestational age.

Conclusion

This is the first study to look at refractive error against all these growth parameters, in preterm and term babies at birth. It would appear from this study that birth weight rather than gestation should be used as criteria for screening for refractive error, especially in developing countries where the incidence of intrauterine malnutrition is higher.     

The Category of Age in the Psychology and Pedagogy of Development

Vygotsky's words, uttered about sixty years ago, may serve as a very special epigraph to the analysis that follows; they have not lost their meaning even today: "The problem of age is not only central to the whole of child psychology: it is the key to all questions of practice as well" [4. P. 260].

The key importance of the concept of age as a category in educational psychology has become obvious now, in light of the urgent need for a reorganization of education, a need to give it a developmental character. This category is just as important for a practice-oriented pedagogy, which can no longer be satisfied with simple study of individual phenomena in educational psychology; it must necessarily become a composite and, even more, a projective science, since it involves contriving complex, synthetic objects that bring together concrete studies, blueprints for educational systems, the programs and technology of continuous education throughout a person's entire life, and expert systems for evaluating and means for monitoring the effectiveness of such continuous education.     

Characteristics of Old-Growth and Secondary Forests in Relation to Age and Typhoon Disturbance

Many properties of forest ecosystems, such as species composition and forest structure, naturally vary with forest age. However, in regions prone to cyclone disturbances, both forest age and cyclone severities can play a role shaping these properties. To evaluate potential effects of an altered cyclone regime on forest ecosystems, it is necessary to disentangle the roles of cyclones and forest age on different forest characteristics. In this study, we compared species composition and forest structure at plot level across sites with similar climate and topographic backgrounds, yet differing in age and typhoon severities in northeastern Taiwan. We found shorter tree stature, higher wood density, higher tree species diversity, and lower typhoon-induced tree mortality in the sites with more severe typhoon disturbances. On the other hand, regardless of typhoon severity, the sites of younger ages had a considerably smaller amount of woody debris, suggesting that it takes time for the accumulation of woody debris. More typhoon-induced canopy gaps at sites with more severe typhoon influences highlights a role of typhoons in canopy dynamics. However, the lack of gaps prior to typhoon disturbances in the less severely affected forest is likely related to the low background mortality associated with the relative young age of the forest. Our results indicate that frequent or severe typhoon disturbances can homogenize some of the structural differences among forests of different ages. If the frequency or severity of cyclones increase in the future, many forests, including old-growth forests, may gradually lose large trees.     

Risk Assessment of Adverse Birth Outcomes in Relation to Maternal Age

Background

Although a number of studies have investigated correlations of maternal age with birth outcomes, an extensive assessment using age as a continuous variable is lacking. In the current study, we estimated age-specific risks of adverse birth outcomes in childbearing women.

Method

National population-based data containing maternal and neonatal information were derived from the Health Promotion Administration, Taiwan. A composite adverse birth outcome was defined as at least anyone of stillbirth, preterm birth, low birth weight, macrosomia, neonatal death, congenital anomaly, and small for gestational age (SGA). Singletons were further analyzed for outcomes of live birth in relation to each year of maternal age. A log-binomial model was used to adjust for possible confounders of maternal and neonatal factors.

Results

In total, 2,123,751 births between 2001 and 2010 were utilized in the analysis. The risk of a composite adverse birth outcome was significantly higher at extreme maternal ages. In specific, risks of stillbirth, neonatal death, preterm birth, congenital anomaly, and low birth weight were higher at the extremes of maternal age. Furthermore, risk of macrosomia rose proportionally with an increasing maternal age. In contrast, risk of SGA declined proportionally with an increasing maternal age. The log-binomial model showed greater risks at the maternal ages of <26 and > 30 years for a composite adverse birth outcome.

Conclusions

Infants born to teenagers and women at advanced age possess greater risks for stillbirth, preterm birth, neonatal death, congenital anomaly, and low birth weight. Pregnancies at advanced age carry an additional risk for macrosomia, while teenage pregnancies carry an additional risk for SGA. The data suggest that the optimal maternal ages to minimize adverse birth outcomes are 26∼30 years.     

The Fat-Sucrose Seesaw in Relation to Age and Dietary Variety of French Adults

DREWNOWSKI, ADAM, SUSAN AHLSTROM HENDERSON, AMY BETH SHORE, CLAUDE FISCHLER, PAUL PREZIOSI, SERGE HERCBERG. The fatsucrose seesaw in relation to age and dietary variety of French adults. Guidelines for a healthy diet often recommend limiting dietary sugars and fats. Some researchers have called these aims mutually incompatible, suggesting that fat and sugar intakes, when expressed as percent dietary energy, are inversely linked. Others have argued that sugar, more specifically sucrose, acts as a vehicle for dietary fat and serves to suppress the overall quality of the diet. This study examined the relationship between age, sucrose and fat intakes, body mass index (BMI), and measures of dietary diversity and variety in a communitybased sample of 837 French adults. Consistent with other studies, high consumption of added sucrose (in g/day or g/1000 kcal per day) was associated with higher consumption of energy and fat and lower consumption of vegetables and fruit. However, eating patterns were strongly influenced by age. High-sucrose consumers were significantly younger and had lower BMI values than did low-sucrose consumers, who were both older and had higher BMIs. High-sucrose diets had minimal effect on the diet diversity score and were associated with more varied diets, as evidenced by a higher dietary variety score.     

Effect of Age and Sex on the Acquisition of Immunity to Toxoplasmosis in Cats*

SYNOPSIS. The effects of age and sex of the cat on oocyst shedding, multiplication of Toxoplasma gondii in tissues of cats, and acquisition of immunity were investigated after oral inoculation of cats with Toxoplasma cysts. Twenty-five cats varying in age from 1 week to 39 months were killed 7-97 days after inoculation with T. gondii. Homogenates of brain, heart, mesenteric lymph nodes, retina, and blood from these cats were inoculated into mice to test for Toxoplasma infectivity. Toxoplasma was isolated more frequently and in higher titers in mice receiving inocula from cats of the youngest age group (1 week old). Toxoplasma gondii was isolated from tissues of only 2 of 21 cats older than 2 months (at the time of inoculation), although all of the animals shed oocysts within 1 week after ingesting the parasites. The number of oocysts shed varied among littermates of the same sex and between sexes. Generally, cats younger than 12 months shed more oocysts than older cats. The number of oocysts shed by older cats varied considerably; males generally shed more oocysts than the females. However, the numbers of cats examined were too small for statistical comparison. Nevertheless, the observations suggest that cats older than 12 months should not be used in experiments where numbers of oocysts shed is critical.     

Hip Fracture Incidence in Relation to Age,Menopausal Status,and Age at Menopause: Prospective Analysis

Background

Bone mineral density is known to decrease rapidly after the menopause. There is limited evidence about the separate contributions of a woman''s age, menopausal status and age at menopause to the incidence of hip fracture.

Methods and Findings

Over one million middle-aged women joined the UK Million Women Study in 1996–2001 providing information on their menopausal status, age at menopause, and other factors, which was updated, where possible, 3 y later. All women were registered with the UK National Health Service (NHS) and were routinely linked to information on cause-specific admissions to NHS hospitals. 561,609 women who had never used hormone replacement therapy and who provided complete information on menopausal variables (at baseline 25% were pre/perimenopausal and 75% postmenopausal) were followed up for a total of 3.4 million woman-years (an average 6.2 y per woman). During follow-up 1,676 (0.3%) were admitted to hospital with a first incident hip fracture. Among women aged 50–54 y the relative risk (RR) of hip fracture risk was significantly higher in postmenopausal than premenopausal women (adjusted RR 2.22, 95% confidence interval [CI] 1.22–4.04; p = 0.009); there were too few premenopausal women aged 55 y and over for valid comparisons. Among postmenopausal women, hip fracture incidence increased steeply with age (p<0.001), with rates being about seven times higher at age 70–74 y than at 50–54 y (incidence rates of 0.82 versus 0.11 per 100 women over 5 y). Among postmenopausal women of a given age there was no significant difference in hip fracture incidence between women whose menopause was due to bilateral oophorectomy compared to a natural menopause (adjusted RR 1.20, 95% CI 0.94–1.55; p = 0.15), and age at menopause had little, if any, effect on hip fracture incidence.

Conclusions

At around the time of the menopause, hip fracture incidence is about twice as high in postmenopausal than in premenopausal women, but this effect is short lived. Among postmenopausal women, age is by far the main determinant of hip fracture incidence and, for women of a given age, their age at menopause has, at most, a weak additional effect.Please see later in the article for the Editors'' Summary