Selenium serum concentrations in malnourished Ecuadorian children: a case-control study

Little is known about the selenium status of children living in the Andean regions of South America, which commonly have volcanic soil with low selenium content. Human selenium deficiency has been hypothesized to have a negative impact on immune function and to increase the risk of infection. The objective of this study was to evaluate the serum selenium concentrations of severely malnourished children living in urban and rural Andean Ecuador, and to compare them to a control group of normally nourished children from the same communities. Forty-three children, aged six to 36 months, with marasmus or kwashiorkor and 30 control children were enrolled from July to November 1993 in Quito, Ecuador. Serum selenium concentrations were lower in the children with marasmus (0.91 +/- 0.28 microM/L, n = 21) and kwashiorkor (0.37 +/- 0.15 microM/L, n = 22) than in those who were normally nourished (1.77 +/- 0.75 microM/L, n = 30, p < 0.001 for each difference). The serum selenium concentrations in children with kwashiorkor were significantly lower than those in children with marasmus (p < 0.001). All 22 of the children with kwashiorkor, 15 of the 21 children with marasmus, and five of the 30 normal children had serum levels < 1.08 microM/L (8.5 micrograms/dL) (chi 2 = 38.4, p < 0.00000001). In the Andean regions of Ecuador, selenium deficiency is prevalent in children with protein and caloric deficiency. Furthermore, 17% of Ecuadorian children with normal weight-for age-Z score are selenium-deficient.     

Imaging practice in low-grade gliomas among European specialized centers and proposal for a minimum core of imaging

Objective

Imaging studies in diffuse low-grade gliomas (DLGG) vary across centers. In order to establish a minimal core of imaging necessary for further investigations and clinical trials in the field of DLGG, we aimed to establish the status quo within specialized European centers.

Methods

An online survey composed of 46 items was sent out to members of the European Low-Grade Glioma Network, the European Association of Neurosurgical Societies, the German Society of Neurosurgery and the Austrian Society of Neurosurgery.

Results

A total of 128 fully completed surveys were received and analyzed. Most centers (n?=?96, 75%) were academic and half of the centers (n?=?64, 50%) adhered to a dedicated treatment program for DLGG. There were national differences regarding the sequences enclosed in MRI imaging and use of PET, however most included T1 (without and with contrast, 100%), T2 (100%) and TIRM or FLAIR (20, 98%). DWI is performed by 80% of centers and 61% of centers regularly performed PWI.

Conclusion

A minimal core of imaging composed of T1 (w/wo contrast), T2, TIRM/FLAIR, PWI and DWI could be identified. All morphologic images should be obtained in a slice thickness of ≤?3 mm. No common standard could be obtained regarding advanced MRI protocols and PET.

Importance of the study

We believe that our study makes a significant contribution to the literature because we were able to determine similarities in numerous aspects of LGG imaging. Using the proposed “minimal core of imaging” in clinical routine will facilitate future cooperative studies.

     

Odor perception: multiple chemical sensitivities, chronic fatigue, and asthma

Patients with multiple chemical sensitivities (MCS) often report heightened sensitivity to odors. Odor detection thresholds to phenyl ethyl alcohol (PEA) and pyridine (PYR) were evaluated as a measure of odor sensitivity for 33 MCS subjects, 13 chronic fatigue syndrome subjects, 16 asthmatic subjects, and 27 healthy controls. Odor identification ability (based on University of Pennsylvania Smell Identification Test results) and ratings in response to four suprathreshold levels of PEA and PYR were also assessed. Odor detection thresholds for PEA and PYR and odor identification ability were equivalent for all groups; however, when exposed to suprathreshold concentrations of PEA, MCS subjects reported significantly more trigeminal symptoms and lower esthetic ratings of PEA. No group differences were found in response to suprathreshold concentrations of PYR. In summary, MCS subjects did not demonstrate lower olfactory threshold sensitivity or enhanced ability to identify odors accurately. Furthermore, they were differentiated from the other groups in their symptomatic and esthetic ratings of PEA, but not PYR.     

Comparison of on- and off-axis photorefraction with cycloplegic retinoscopy in infants.

We have compared the performance of an off-axis (knife-edge) photorefractor with that of an on-axis (isotropic) system. Normal infants and children between the ages of 8 and 208 weeks were photographed with each camera both with and without cycloplegia. Refractive errors were estimated for each technique based on equations derived from ray-tracing. These refractions were compared to the results of retinoscopy under cycloplegia. Sensitivity and specificity of the two photorefraction systems were evaluated as a function of the magnitude of meridional hyperopia defined by retinoscopy. We also examined the effect of varying the photorefraction screening criterion. Thirteen percent of the infants in the screening sample presented with +3.50 diopters or more of meridional hyperopia. Using this level of ametropia as a referral criterion, the sensitivity and specificity of the off-axis system for infants without cycloplegia were 83% and 72%, respectively. For the on-axis system, sensitivity and specificity values were 85% and 53%. The use of cycloplegics did not significantly improve the performance of either system, but rather their use degraded the specificity of the on-axis system in the presence of moderate refractive errors. The results of the present study indicate that both on- and off-axis systems are effective in identifying highly ametropic infants, but that the off-axis system results in significantly fewer false positives. Moreover, the off-axis system has the advantages of an inherently greater dynamic range for a fixed camera design, and also more easily interpreted photographs.     

Sexual receptivity of bilaterally adrenalectomised female rhesus monkeys

Bilateral adrenalectomy (with cortisol replacement) of ovariectomised, oestrogentreated rhesus monkeys greatly decreased their sexual receptivity: they presented less to and refused the mounting attempts of males with whom they were paired. As a consequence the levels of the latter's sexual activity was low. Two hundred or 400 μg androstenedione/day increased the receptivity of these females, but dehydroepiandrosterone (up to 5,000 μg/day) was ineffective. Vaginal cornification, sexual skin colour and the size of the clitoris were measured and showed no significant change during the experiment. It is concluded that adrenal androgens are necessary to maintain sexual receptivity in the female rhesus monkey: the site of action of these androgens is discussed.     

Recombination and allelic association in the Xq/Yq homology region

The ends of the long arms of the human X and Y chromosomes containa homologous region that can undergo sequence exchange. We havedeveloped new polymorphic markers to analyze the genetic behaviorof this region in the three-generation CEPH reference families.These Xq/Yq markers undergo crossovers in approximately 2% ofmale meioses in a pattern consistent with reciprocal recombinationrather than gene conversion. Although the rate of recombinationin males is significantly higher than in females or in autosomalsequences, it is more than an order of magnitude lower thanin the short arm pseudoautosomal region at Xp/Yp. The Xq/Yqmarkers exhibit allelic association with one another, but notwith markers in the X-specific or Y-specific regions of thesex chromosomes. Hence the Xq/Yq homology region displays behaviorthat is intermediate between sex-linked and true pseudoautosomal,and is unlikely to be essential for proper chromosome segregation.     

Pleiotropy of the serotonin transporter gene for seasonality and neuroticism

Pleiotropy refers to the ability of a single gene to influence multiple traits. A polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) has previously been found to be associated both with the personality trait of neuroticism and with seasonal changes in mood and behavior, or seasonality. Hypothesizing that the contribution of the serotonin transporter gene to seasonality is specific, i.e. independent of neuroticism, we measured 5-HTTLPR genotypes and both psychological traits in 236 healthy volunteers. The results indicated that the 5-HTTLPR contributions to variation in the two traits are largely independent; approximately three-quarters of the effect of the gene on seasonality are not related to its effects on neuroticism. Moreover, the gene has a larger effect on the covariation between neuroticism and seasonality than it does on either trait alone. Sibling-pair analysis confirmed that the effects of the 5-HTTLPR are due to genetic pleiotropy rather than population stratification.