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Background There are inconsistent findings regarding the relationship between body mass index (BMI), fear of falling and body balance, especially on unstable surfaces. Objectives To investigate whether obesity is associated with worse postural balance and fear of falling in older adults. Methods A cross-sectional study was conducted with 201 older adults, classified as normal weight, overweight, or obese according to BMI. Postural balance was evaluated on stable and unstable surfaces on the Biodex Balance System platform under three visual conditions: with and without visual feedback and with eyes closed. Fear of falling was identified by a dichotomous question and the Falls Efficacy Scale. These data were compared between groups and included in adjusted multiple linear regression analysis. Results The study showed no significant differences (p > 0.05) in body oscillations on a stable surface between the three groups. On an unstable surface, the obese older adults exhibited body oscillations from 0.61° [95% CI 0.07, 1.30] to 1.63° [95% CI 0.84, 2.41] greater than those with normal weight in the three visual conditions. The obese older adults also displayed larger mediolateral oscillations with visual feedback (mean difference: 0.50° [95% CI 0.01, 0.98]) as well as greater global oscillations without visual feedback (mean difference of 0.82° [95% CI 0.18, 1.81]) and with progressive instability (mean difference: 0.80° [95% CI 0.05, 1.66]) than the overweight older adults. BMI explained from 6 to 12% of body swings investigated on unstable surface. Obesity was not associated with fear of falling. Conclusion Obesity was associated with reduced postural stability on unstable surfaces but not with fear of falling in older adults.

Background and aims GPIHBP1 is an accessory protein of lipoprotein lipase (LPL) essential for its functioning. Mutations in the GPIHBP1 gene cause a deficit in the action of LPL, leading to severe hypertriglyceridemia and increased risk for acute pancreatitis. Methods We describe twelve patients (nine women) with a novel homozygous mutation in intron 2 of the GPIHBP1 gene. Results All patients were from the Northeastern region of Brazil and presented the same homozygous variant located in a highly conserved 3′ splicing acceptor site of the GPIHBP1 gene. This new variant was named c.182-1G > T, according to HGVS recommendations. We verified this new GPIHBP1 variant's effect by using the Human Splicing Finder (HSF) tool. This mutation changes the GPIHBP1 pre-mRNA processing and possibly causes the skipping of the exon 3 of the GPIHBP1 gene, affecting almost 50% of the cysteine-rich Lys6 GPIHBP1 domain. Patients presented with severe hypertriglyceridemia (2351 mg/dl [885–20600]) and low HDL (18 mg/dl [5–41). Four patients (33%) had a previous history of acute pancreatitis. Conclusions We describe a novel GPIHBP1 pathogenic intronic mutation of patients from the Northeast region of Brazil, suggesting the occurrence of a founder effect.

Berardinelli-Seip congenital lipodystrophy (BSCL) is a rare autosomal recessive syndrome characterized by a difficulty storing lipid in adipocytes, low body fat, hypoleptinemia, and hyperinsulinemia. We report here laboratory, bone mineral density (BMD), and bone mineral content findings of 21 patients (24.1 ± 8.4 yr old, 14 females, 18 diabetics, 5.3% total body fat) with BSCL. The mean leptin was very low (0.91 ± 0.42 ng/mL), and the mean values of the Z -scores for all studied sites were positive, except for the 33% radius ( Z -score −0.5 standard deviation [SD]). Twelve patients (57.1%) had a BMD Z -score higher than +2.5 SD in at least 1 site. There was no significant difference in the Z -scores between males and females. None of type 1 ( AGPAT2 ) patients had Z -scores higher than +2.5 SD, and these patients had a smaller Z -score of BMD total body (0.26 SD vs 1.90 SD, p = 0.022) and of bone mineral content (1.59 SD vs 3.3 SD, p = 0.032) than type 2 (seipin) patients. Insulin, as well as HOMA IR (homeostasis model assessment), correlated positively with the BMD of all sites, except for the 33% radius. Z -Scores on this site (33% radius) were the smallest of all. More than half of our patients with BSCL have BMD Z -scores higher than +2.5 SD on at least 1 site, and this increase is more pronounced in the trabecular sites and in type 2 patients.

Free radicals and other reactive species are involved in normal ovarian physiology. However, they are also highly reactive with complex cellular molecules (proteins, lipids, and DNA) and alter their functions leading to oxidative stress. Oxidative damage may play a prominent role in the development of disorders that considerably influence female fertility. Melatonin, because of its amphiphilic nature that allows for crossing morphophysiological barriers, is an effective antioxidant for protecting macromolecules against oxidative stress caused by reactive species. The balance between reactive oxygen species and antioxidants within the follicle seems to be critical to the function of the oocyte and granulosa cells and evidence has accumulated showing that melatonin is involved in the protection of these cells. Melatonin appears to have varied functions at different stages of follicle development, oocyte maturation, and luteal stage. Melatonin concentration in the growing follicle may be an important factor in avoiding atresia, because melatonin in the follicular fluid reduces apoptosis of critical cells. Melatonin also has protective actions during oocyte maturation reducing intrafollicular oxidative damage. An association between melatonin concentrations in follicular fluid and oocyte quality has been reported; this would allow a preovulatory follicle to fully develop and provide a competent oocyte for fertilization. The functional role of reactive species and the cytoprotective properties of melatonin on the ovary from oxidative damage are summarized in this brief review.

The aim of this brief review is to clarify the role of melatonin in the production and preservation of mammalian gametes and embryos. Melatonin is an indoleamine synthesized from tryptophan in the pineal gland and other organs that operates as a hypothalamic-pituitary-gonadal axis modulator and regulates the waxing and waning of seasonal reproductive competence in photoperiodic mammals. A major function of the melatonin rhythm is to transmit information about the length of the daily photoperiod to the circadian and circannual systems in order to provide time-of-day and time-of-year information, respectively, to the organism. Melatonin is also a powerful antioxidant and anti-apoptotic agent, which is due to its direct scavenging of toxic oxygen derivatives and its ability to reduce the formation of reactive species. Mammalian gametes and embryos are highly vulnerable to oxidative stress due to the presence of high lipid levels; during artificial breeding procedures, these structures are exposed to dramatic changes in the microenvironment, which have a direct bearing on their function and viability. Free radicals influence the balance between oxidation-reduction reactions, disturb the transbilayer-phospholipid asymmetry of the plasma membrane and enhance lipid peroxidation. Melatonin, due to its amphiphilic nature, is undoubtedly useful in tissues by protecting them from free radical-mediated oxidative damage and cellular death. The supplementation of melatonin to semen extender or culture medium significantly improves sperm viability, oocyte competence and blastocyst development in vitro.

The microgravity environment aboard orbiting spacecraft has provided a unique laboratory to explore topics in basic plant biology as well as applied research on the use of plants in bioregenerative life support systems. Our group has utilized the European Modular Cultivation System (EMCS) aboard the International Space Station (ISS) to study plant growth, development, tropisms, and gene expression in a series of spaceflight experiments. The most current project performed on the ISS was termed Seedling Growth-1 (SG-1) which builds on the previous TROPI (for tropi sms) experiments performed in 2006 and 2010. Major technical and operational changes in SG-1 (launched in March 2013) compared to the TROPI experiments include: (1) improvements in lighting conditions within the EMCS to optimize the environment for phototropism studies, (2) the use of infrared illumination to provide high-quality images of the seedlings, (3) modifications in procedures used in flight to improve the focus and overall quality of the images, and (4) changes in the atmospheric conditions in the EMCS incubator. In SG-1, a novel red-light-based phototropism in roots and hypocotyls of seedlings that was noted in TROPI was confirmed and now can be more precisely characterized based on the improvements in procedures. The lessons learned from sequential experiments in the TROPI hardware provide insights to other researchers developing space experiments in plant biology.

Successful growth and development of higher plants in space rely on adequate availability and uptake of water and nutrients, and efficient energy distribution through photosynthesis and gas exchange. In the present review, literature has been reviewed to assemble the relevant knowledge within space plant research for future planetary missions. Focus has been on fractional gravity, space radiation, magnetic fields and ultimately a combined effect of these factors on gas exchange, photosynthesis and transport of water and solutes. Reduced gravity prevents buoyancy driven thermal convection in the physical environment around the plant and alters transport and exchange of gases and liquids between the plant and its surroundings. In space experiments, indications of root zone hypoxia have frequently been reported, but studies on the influences of the space environment on plant nutrition and water transport are limited or inconclusive. Some studies indicate that uptake of potassium is elevated when plants are grown under microgravity conditions. Based on the current knowledge, gas exchange, metabolism and photosynthesis seem to work properly in space when plants are provided with a well stirred atmosphere and grown at moderate light levels. Effects of space radiation on plant metabolism, however, have not been studied so far in orbit. Ground experiments indicated that shielding from the Earth’s magnetic field alters plant gas exchange and metabolism, though more studies are required to understand the effects of magnetic fields on plant growth. It has been shown that plants can grow and reproduce in the space environment and adapt to space conditions. However, the influences of the space environment may result in a long term effect over multiple generations or have an impact on the plants’ role as food and part of a regenerative life support system. Suggestions for future plant biology research in space are discussed.

OBJECTIVE: The aim of this study was to evaluate the multisegmental static postural balance of active eutrophic and obese elderly women using a three-dimensional system under different sensory conditions. METHODS: A cross-sectional study was conducted on 31 elderly women (16 eutrophic and 15 obese) aged 65 to 75 years. The following anthropometric measurements were obtained: weight, height, waist and hip circumference, and handgrip strength. The physical activity level was evaluated using the International Physical Activity Questionnaire. Body composition was measured using the deuterium oxide dilution technique. The Polhemus® Patriot (three-dimensional) equipment was used to measure the parameters of postural balance along the anteroposterior and laterolateral axes. The data acquisition involved one trial of 60 s to test the limit of stability and four trials of 90 s each under the following conditions: (1) eyes open, stable surface; (2) eyes closed, stable surface; (3) eyes open, unstable surface; and (4) eyes closed, unstable surface. RESULTS: For the limit of stability, significant differences were observed in the maximum anteroposterior and laterolateral displacement (p

Due to the periodic exposure to air during periods of low tide, desiccation can be expected to cause important limiting effects on the photosynthetic activity of intertidal microphytobenthos biofilms. This work addresses the study of the short-term effects of desiccation on microphytobenthos using a new, simple methodological approach to non-destructively estimate the water content of muddy intertidal sediments. The method is based on the non-destructive measurement of the specular reflectance in the visible spectral region, shown to be linearly related to the water content of the uppermost 200 µm of the sediment. During air exposure, water loss by the surface sediment layers was shown to induce marked decreases in both the photosynthetic activity, as measured by the maximum quantum yield of photosystem II, Fv/Fm, and the surface microalgal biomass, as estimated from the diffusive reflectance biomass index NDVI. The effects of desiccation were largely dependent on the rate of sediment de-watering. For a same level of desiccation, samples under fast desiccation (exposed to wind of 4.2 m s− 1) showed much larger effects on Fv/Fm and NDVI comparatively to samples under slow desiccation (maintained under still air). By showing the rapid and significant effects of desiccation on microphytobenthos biofilm functioning, the results of this study have potentially important implications for the modelling of primary productivity of estuarine intertidal areas, as desiccation and factors inducing it may result in previously unaccounted effects on photosynthetic performance and productive biomass.

To assess how ultrasonography can contribute during the evaluation of a thyroid nodule and whether this technique can have a role in predicting malignant involvement.In this retrospective study, data were analyzed on 220 consecutive patients (with 348 thyroid nodules) who underwent thyroidectomy and had previously undergone assessment by high-resolution thyroid ultrasonography. Nodule size, echogenicity, regularity of margins, halo sign, presence or absence of calcifications, and invasion of surrounding tissues were evaluated. The nodules were classified as low, medium, or high risk for malignant involvement on the basis of nodule characteristics found on ultrasonography. All nodules were submitted to cytologic examination by fine-needle aspiration (FNA) before thyroidectomy. Ultrasound, FNA, and pathologic postoperative results were compared.Among the 348 thyroid nodules, 56 were ultrasonographically classified as low risk, 268 as medium risk, and 24 as high risk for malignant potential. Fifty of 56 (89.3%) low-risk nodules and 213 of 268 (79.5%) medium-risk nodules were diagnosed as benign at pathologic postoperative examination. In contrast, however, only 6 of 24 (25%) high-risk nodules were diagnosed as benign. Among the 18 high-risk nodules of 1-cm diameter or larger, FNA showed a 20% false-negative result.High-risk classification of a thyroid nodule on ultrasonography had a positive predictive value for malignant involvement of 75%. Nodule characteristics analyzed by ultrasonography should be considered at the time of surgical intervention.

The migratory response of intertidal microphytobenthos to changes in irradiance was studied on undisturbed estuarine sediments. Two non-destructive optical techniques were used to trace variations in vivo of surface biomass: PAM fluorometry, for measuring the minimum fluorescence level ( F o ); and spectral reflectance analysis, for quantifying the normalized difference vegetation index (NDVI). Following the formation of a dense biofilm at the surface, replicated sediment samples were simultaneously exposed to six different irradiance levels, ranging from 50 to 1500 μmol m −2 s −1 , during a period of 120 min. The migratory photoresponse of the biofilms was characterised by constructing biomass vs. light curves (BLC), relating the accumulation of microalgal biomass after that period (estimated by F o or NDVI) to the irradiance level incident on the surface. BLCs allow characterising the main features of the migratory photoresponse of intact biofilms. Typical BLC showed a clear biphasic pattern, with an increase in microalgal accumulation under irradiances below 100 μmol m −2 s −1 , maximum values under 100–250 μmol m −2 s −1 , and a gradual decrease of surface biomass under higher irradiances, indicating a strong photophobic downward migratory response. Similar BLC patterns were obtained when measuring F o or NDVI. The construction of BLCs for biofilms from intertidal sites with distinctive sediment characteristics and diatom taxonomic composition allowed to detected significant differences in the migratory photoresponse. Biofilms from a muddy sediment exhibited considerably larger amplitude in the migratory photoresponse than the biofilms from a sandy mud site, especially under high irradiances. The photophobic migratory response to high light was found to vary among diatom species, particularly in the case of the biofilms from the muddy sediments.