GDF15 linked to maternal risk of nausea and vomiting during pregnancy

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with β-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Fetally-encoded GDF15 and maternal GDF15 sensitivity are major determinants of nausea and vomiting in human pregnancy

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Does digital media use contribute to decreased expressive language skills of pre-school-aged children? An exploratory study in Portuguese children

PURPOSE/AIM OF THE STUDY

The purpose of this study was to analyse the relationship between digital media use and expressive language skills in the semantic and morphosyntactic domains, of pre-school-aged children (3 years-and-0 months to 5 years-and-11 months).

MATERIALS AND METHODS

Verbal oral expression (VOE) tasks of the Pre-school Assessment of Language Test (Teste de Linguagem-Avaliação da Linguagem Pré-Escolar) were administered to 237 pre-school children with no previous identified neurological or developmental conditions associated with language disorders to assess expressive language skills in the semantic and morphosyntactic domains. Parents completed a questionnaire about their children's medical conditions, development (using the milestones of the Survey of Well-being of Young Children and the Pre-school Paediatric Symptom Checklist), and exposure to screens (using ScreenQ). Correlations between VOE and continuous variables such as ScreenQ were computed and a regression model incorporating all variables significantly associated with total language verbal expression was created.

RESULTS

ScreenQ revealed a negative and significant correlation with children's verbal oral expression as well as significance in the regression model. Parents' education was the most significant predictor in this regression model.

CONCLUSIONS

This study emphasizes the importance of parents establishing limits for digital media use and promote good practices such as co-viewing.

Real-Time Blink Detection as an Indicator of Computer Vision Syndrome in Real-Life Settings: An Exploratory Study

With the increase in the number of people using digital devices, complaints about eye and vision problems have been increasing, making the problem of computer vision syndrome (CVS) more serious. Accompanying the increase in CVS in occupational settings, new and unobstructive solutions to assess the risk of this syndrome are of paramount importance. This study aims, through an exploratory approach, to determine if blinking data, collected using a computer webcam, can be used as a reliable indicator for predicting CVS on a real-time basis, considering real-life settings. A total of 13 students participated in the data collection. A software that collected and recorded users' physiological data through the computer's camera was installed on the participants' computers. The CVS-Q was applied to determine the subjects with CVS and its severity. The results showed a decrease in the blinking rate to about 9 to 17 per minute, and for each additional blink the CVS score lowered by 1.26. These data suggest that the decrease in blinking rate was directly associated with CVS. These results are important for allowing the development of a CVS real-time detection algorithm and a related recommendation system that provides interventions to promote health, well-being, and improved performance.

Numerical Analysis of Micro-Residual Stresses in a Carbon/Epoxy Polymer Matrix Composite during Curing Process

The manufacturing process in thermoset-based carbon fiber-reinforced polymers (CFRPs) usually requires a curing stage where the material is transformed from a gel state to a monolithic solid state. During the curing process, micro-residual stresses are developed in the material due to the different chemical–thermal–mechanical properties of the fiber and of the polymer, reducing the mechanical performance of the composite material compared to the nominal performance. In this study, computational micromechanics is used to analyze the micro-residual stresses development and to predict its influence on the mechanical performance of a pre-impregnated unidirectional CFRP made of T700-fibers and an aeronautical grade epoxy. The numerical model of a representative volume element (RVE) was developed in the commercial software Abaqus^® and user-subroutines are used to simulate the thermo-curing process coupled with the mechanical constitutive model. Experimental characterization of the bulk resin properties and curing behavior was made to setup the models. The higher micro-residual stresses occur at the thinner fiber gaps, acting as triggers to failure propagation during mechanical loading. These micro-residual stresses achieve peak values above the yield stress of the resin 55 MPa, but without achieving damage. These micro-residual stresses reduce the transverse strength by at least 10%, while the elastic properties remain almost unaffected. The numerical results of the effective properties show a good agreement with the macro-scale experimentally measured properties at coupon level, including transverse tensile, longitudinal shear and transverse shear moduli and strengths, and minor in-plane and transverse Poisson’s ratios. A sensitivity analysis was performed on the thermal expansion coefficient, chemical shrinkage, resin elastic modulus and cure temperature. All these parameters change the micro-residual stress levels and reduce the strength properties.

Identification of Rare Loss-of-Function Genetic Variation Regulating Body Fat Distribution

CONTEXT

Biological and translational insights from large-scale, array-based genetic studies of fat distribution, a key determinant of metabolic health, have been limited by the difficulty in linking predominantly noncoding variants to specific gene targets. Rare coding variant analyses provide greater confidence that a specific gene is involved, but do not necessarily indicate whether gain or loss of function (LoF) would be of most therapeutic benefit.

OBJECTIVE

This work aimed to identify genes/proteins involved in determining fat distribution.

METHODS

We combined the power of genome-wide analysis of array-based rare, nonsynonymous variants in 450 562 individuals in the UK Biobank with exome-sequence-based rare LoF gene burden testing in 184 246 individuals.

RESULTS

The data indicate that the LoF of 4 genes (PLIN1 [LoF variants, P = 5.86 × 10-7], INSR [LoF variants, P = 6.21 × 10-7], ACVR1C [LoF + moderate impact variants, P = 1.68 × 10-7; moderate impact variants, P = 4.57 × 10-7], and PDE3B [LoF variants, P = 1.41 × 10-6]) is associated with a beneficial effect on body mass index-adjusted waist-to-hip ratio and increased gluteofemoral fat mass, whereas LoF of PLIN4 (LoF variants, P = 5.86 × 10-7 adversely affects these parameters. Phenotypic follow-up suggests that LoF of PLIN1, PDE3B, and ACVR1C favorably affects metabolic phenotypes (eg, triglycerides [TGs] and high-density lipoprotein [HDL] cholesterol concentrations) and reduces the risk of cardiovascular disease, whereas PLIN4 LoF has adverse health consequences. INSR LoF is associated with lower TG and HDL levels but may increase the risk of type 2 diabetes.

CONCLUSION

This study robustly implicates these genes in the regulation of fat distribution, providing new and in some cases somewhat counterintuitive insight into the potential consequences of targeting these molecules therapeutically.

New taxonomy for prolonged disorders of consciousness may help with decisions on withdrawal of clinically assisted nutrition and hydration: A proposed decision-making pathway

The number of patients surviving severe brain injury is increasing; however, many are left in a prolonged disorder of consciousness. With appropriate treatment, patients with prolonged disorders of consciousness can survive for years. Unless an advance directive exists, the treating clinicians can authorize withdrawal of clinically assisted nutrition and hydration for these patients, based on best interests. The classic terminology used in prolonged disorders of consciousness ranges from coma, vegetative state to minimally conscious state. However, a new group of patients with covert cognition has been identified in the last decade, making it necessary to revise the current taxonomy to better reflect our understanding of these conditions. With the introduction of a less ambiguous terminology, the challenges when it comes to withdrawal of clinically assisted nutrition and hydration of these patients may ease. A decision-making pathway for withdrawal of clinically assisted nutrition and hydration for patients with prolonged disorders of consciousness, based on a new taxonomy is proposed. These decisions should be based primarily on best interests. The adoption of a new classification for impairments of consciousness would clarify and improve how we think about these patients. Moreover, the development of accurate prognostic predictors would be a major step in the decision-making process, as it would influence the beneficent pathway towards the best clinical outcome.

End-of-Life Recycling Options of (Nano)Enhanced CFRP Composite Prototypes Waste-A Life Cycle Perspective

Life cycle assessment is a methodology to assess environmental impacts associated with a product or system/process by accounting resource requirements and emissions over its life cycle. The life cycle consists of four stages: material production, manufacturing, use, and end-of-life. This study highlights the need to conduct life cycle assessment (LCA) early in the new product development process, as a means to assess and evaluate the environmental impacts of (nano)enhanced carbon fibre-reinforced polymer (CFRP) prototypes over their entire life cycle. These prototypes, namely SleekFast sailing boat and handbrake lever, were manufactured by functionalized carbon fibre fabric and modified epoxy resin with multi-walled carbon nanotubes (MWCNTs). The environmental impacts of both have been assessed via LCA with a functional unit of '1 product piece'. Climate change has been selected as the key impact indicator for hotspot identification (kg CO2 eq). Significant focus has been given to the end-of-life phase by assessing different recycling scenarios. In addition, the respective life cycle inventories (LCIs) are provided, enabling the identification of resource hot spots and quantifying the environmental benefits of end-of-life options.

The Auditory N1 in Schizophrenia: Comparative Analysis with a Monoaural Stimuli Paradigm

The auditory N1 component has been gaining interest as a possible biomarker in schizophrenia (SCZ). N1 to right (RE) and left ear (LE) amplitudes and latencies were assessed using a monoaural auditory oddball paradigm in 12 SCZ subjects and 15 matched healthy controls (M=40.1±8.53 and 39.4±7.73, respectively). T-student test revealed no differences between RE and LE stimulation for N1 amplitude and latency to both groups. However, there were differences in peak-to-peak N1 amplitudes between the two groups for both LE (t=-3.067; ρ=0.003) and RE (t=-2.794; ρ=0.007). These findings strengthen auditory N1 has an electrophysiological biomarker for schizophrenia.

Human pluripotent stem cell-based models suggest preadipocyte senescence as a possible cause of metabolic complications of Werner and Bloom Syndromes

Werner Syndrome (WS) and Bloom Syndrome (BS) are disorders of DNA damage repair caused by biallelic disruption of the WRN or BLM DNA helicases respectively. Both are commonly associated with insulin resistant diabetes, usually accompanied by dyslipidemia and fatty liver, as seen in lipodystrophies. In keeping with this, progressive reduction of subcutaneous adipose tissue is commonly observed. To interrogate the underlying cause of adipose tissue dysfunction in these syndromes, CRISPR/Cas9 genome editing was used to generate human pluripotent stem cell (hPSC) lacking either functional WRN or BLM helicase. No deleterious effects were observed in WRN^−/− or BLM^−/− embryonic stem cells, however upon their differentiation into adipocyte precursors (AP), premature senescence emerged, impairing later stages of adipogenesis. The resulting adipocytes were also found to be senescent, with increased levels of senescent markers and senescence-associated secretory phenotype (SASP) components. SASP components initiate and reinforce senescence in adjacent cells, which is likely to create a positive feedback loop of cellular senescence within the adipocyte precursor compartment, as demonstrated in normal ageing. Such a scenario could progressively attenuate adipose mass and function, giving rise to “lipodystrophy-like” insulin resistance. Further assessment of pharmacological senolytic strategies are warranted to mitigate this component of Werner and Bloom syndromes.

Effects on Volume Load and Ratings of Perceived Exertion in Individuals' Advanced Weight Training After Transcranial Direct Current Stimulation

Lattari, E, Rosa Filho, BJ, Fonseca Junior, SJ, Murillo-Rodriguez, E, Rocha, N, Machado, S, and Maranhão Neto, GA. Effects on volume load and ratings of perceived exertion in individuals' advanced weight training after transcranial direct current stimulation. J Strength Cond Res 34(1): 89-96, 2020-The aim of this study was investigate the effects of transcranial direct current stimulation (tDCS) on volume load and ratings of perceived exertion. Fifteen young healthy individuals, aged between 20 and 30 years in advanced strength training were recruited. Test and retest of the 10 maximum repetitions (10RM) were performed to determine the reliability of load used. Subjects performed 3 experimental conditions in a randomized, double-blinded crossover design: anodic stimulation (a-tDCS), cathodic stimulation (c-tDCS), and sham (2 mA for 20 minutes targeting the dorsolateral prefrontal cortex left). Immediately after the experimental conditions, subjects completed 1 set of maximum repetitions with 10RM load (volume load) and answered to OMNI-RES (poststimulation) (level of significance p ≤ 0.05). The volume load showed main effect for condition (F(2, 28) = 164.801; p < 0.001). In poststimulation, a-tDCS was greater than c-tDCS (p ≤ 0.001) and sham (p ≤ 0.001). For ratings of perceived exertion (OMNI-RES), the results showed main effect for condition (F(2, 28) = 9.768; p ≤ 0.05). In poststimulation, c-tDCS was greater than a-tDCS (p ≤ 0.05) and sham (p ≤ 0.05). We conclude that the use of a-tDCS may promote increase in volume load for the LP45 exercise. Moreover, higher volume loads are necessary to maximize muscle strength and anabolism.

A genome-wide RNAi screen identifies the SMC5/6 complex as a non-redundant regulator of a Topo2a-dependent G2 arrest

The Topo2a-dependent arrest is associated with faithful segregation of sister chromatids and has been identified as dysfunctional in numerous tumour cell lines. This genome-protecting pathway is poorly understood and its characterization is of significant interest, potentially offering interventional opportunities in relation to synthetic lethal behaviours in arrest-defective tumours. Using the catalytic Topo2a inhibitor ICRF193, we have performed a genome-wide siRNA screen in arrest-competent, non-transformed cells, to identify genes essential for this arrest mechanism. In addition, we have counter-screened several DNA-damaging agents and demonstrate that the Topo2a-dependent arrest is genetically distinct from DNA damage checkpoints. We identify the components of the SMC5/6 complex, including the activity of the E3 SUMO ligase NSE2, as non-redundant players that control the timing of the Topo2a-dependent arrest in G2. We have independently verified the NSE2 requirement in fibroblasts from patients with germline mutations that cause severely reduced levels of NSE2. Through imaging Topo2a-dependent G2 arrested cells, an increased interaction between Topo2a and NSE2 is observed at PML bodies, which are known SUMOylation hotspots. We demonstrate that Topo2a is SUMOylated in an ICRF193-dependent manner by NSE2 at a novel non-canonical site (K1520) and that K1520 sumoylation is required for chromosome segregation but not the G2 arrest.

Secretome Analysis of Hypoxia-Induced 3T3-L1 Adipocytes Uncovers Novel Proteins Potentially Involved in Obesity

In the obese state, as adipose tissue expands, adipocytes become hypoxic and dysfunctional, leading to changes in the pattern of adipocyte-secreted proteins. To better understand the role of hypoxia in the mechanisms linked to obesity, we comparatively analyzed the secretome of murine differentiated 3T3-L1 adipocytes exposed to normoxia or hypoxia for 24 h. Proteins secreted into the culture media were precipitated by trichloroacetic acid and then digested with trypsin. The peptides were labeled with dimethyl labeling and analyzed by reversed phase nanoscale liquid chromatography coupled to a quadrupole Orbitrap mass spectrometer. From a total of 1508 identified proteins, 109 were differentially regulated, of which 108 were genuinely secreted. Factors significantly downregulated in hypoxic conditions included adiponectin, a known adipokine implicated in metabolic processes, as well as thrombospondin-1 and -2, and matrix metalloproteinase-11, all multifunctional proteins involved in extracellular matrix (ECM) homeostasis. Findings were validated by Western blot analysis. Expression studies of the relative genes were performed in parallel experiments in vitro, in differentiated 3T3-L1 adipocytes, and in vivo, in fat tissues from obese versus lean mice. Our observations are compatible with the concept that hypoxia may be an early trigger for both adipose cell dysfunction and ECM remodeling.

Evaluation of human dermal fibroblasts directly reprogrammed to adipocyte-like cells as a metabolic disease model

Adipose tissue is the primary tissue affected in most single gene forms of severe insulin resistance, and growing evidence has implicated it as a site at which many risk alleles for insulin resistance identified in population-wide studies might exert their effect. There is thus increasing need for human adipocyte models in which to interrogate the function of known and emerging genetic risk variants. However, primary adipocyte cultures, existing immortalised cell lines and stem-cell based models all have significant biological or practical limitations. In an attempt to widen the repertoire of human cell models in which to study adipocyte-autonomous effects of relevant human genetic variants, we have undertaken direct reprogramming of skin fibroblasts to adipocyte-like cells by employing an inducible recombinant lentivirus overexpressing the master adipogenic transcription factor PPARγ2. Doxycycline-driven expression of PPARγ2 and adipogenic culture conditions converted dermal fibroblasts into triglyceride-laden cells within days. The resulting cells recapitulated most of the crucial aspects of adipocyte biology in vivo, including the expression of mature adipocyte markers, secreted high levels of the adipokine adiponectin, and underwent lipolysis when treated with isoproterenol/3-isobutyl-1-methylxanthine (IBMX). They did not, however, exhibit insulin-inducible glucose uptake, and withdrawal of doxycycline produced rapid delipidation and loss of adipogenic markers. This protocol was applied successfully to a panel of skin cells from individuals with monogenic severe insulin resistance; however, surprisingly, even cell lines harbouring mutations causing severe, generalised lipodystrophy accumulated large lipid droplets and induced adipocyte-specific genes. The direct reprogramming protocol of human dermal fibroblasts to adipocyte-like cells we established is simple, fast and efficient, and has the potential to generate cells which can serve as a tool to address some, though not all, aspects of adipocyte function in the presence of endogenous disease-causing mutations.

Summary: Human dermal fibroblasts can be reprogrammed efficiently to adipocyte-like cells that have utility for modelling some aspects of human monogenic metabolic disease.

The metabolic syndrome- associated small G protein ARL15 plays a role in adipocyte differentiation and adiponectin secretion

Common genetic variants at the ARL15 locus are associated with plasma adiponectin, insulin and HDL cholesterol concentrations, obesity, and coronary atherosclerosis. The ARL15 gene encodes a small GTP-binding protein whose function is currently unknown. In this study adipocyte-autonomous roles for ARL15 were investigated using conditional knockdown of Arl15 in murine 3T3-L1 (pre)adipocytes. Arl15 knockdown in differentiated adipocytes impaired adiponectin secretion but not adipsin secretion or insulin action, while in preadipocytes it impaired adipogenesis. In differentiated adipocytes GFP-tagged ARL15 localized predominantly to the Golgi with lower levels detected at the plasma membrane and intracellular vesicles, suggesting involvement in intracellular trafficking. Sequencing of ARL15 in 375 severely insulin resistant patients identified four rare heterozygous variants, including an early nonsense mutation in a proband with femorogluteal lipodystrophy and non classical congenital adrenal hyperplasia, and an essential splice site mutation in a proband with partial lipodystrophy and a history of childhood yolk sac tumour. No nonsense or essential splice site mutations were found in 2,479 controls, while five such variants were found in the ExAC database. These findings provide evidence that ARL15 plays a role in adipocyte differentiation and adiponectin secretion, and raise the possibility that human ARL15 haploinsufficiency predisposes to lipodystrophy.

Relationship Between Brain-Derived Neurotrofic Factor (Bdnf) and Sleep on Depression: A Critical Review

The Brain-Derived Neurotrofic Factor (BDNF) is one of the most important neurotrophins in the brain and it is suggested influences the activity of the serotonergic, noradrenergic and dopaminergic pathways. In the last few years, it has been hypothesized that BDNF level is related with depression and sleep. Several studies show that depressive subjects present low levels of BDNF in the brain. Poor sleep quality is also related with alterations in the BDNF concentration. Some authors argue that most of the cases show that impaired sleep quality increases the stress and, consequently, the vulnerability to depressive disorders, suggesting that there is a relationship between sleep, depression and BDNF levels.

Physical Exercise As Stabilizer For Alzheimer'S Disease Cognitive Decline: Current Status

Introduction:

Mental health decline is one of the main responsible factors for augments in health care costs, and diagnosis of Alzheimer’s disease (AD). Some studies stated physical exercise is useful for reduction in cognitive decline and AD. Moreover, a recent review argued that evidence are scarce due to few studies published and lack of configuration information of exercise protocol, such as intensity and duration of exercise, number of sessions and other relevant data, to allow appropriate assessment.

Materials and Methods:

Here, we discussed the possible confounders or factors responsible for these differences and possible neurophysiological mechanisms.

Results:

Most studies revealed a possible positive association between physical exercise and cognitive assessments. There are inconsistencies in studies design responsible for varying use of cognitive assessments and different assessments of fitness. However, these studies do not fail to provide evidence about the benefits of exercise, but fail to make it possible because of the lack of dose-response information in AD patients. Physical exercise of moderate intensity should be considered as standard recommendation to reduce cognitive decline, probably due to the improvement in neurodegenerative mechanisms, and the increase in neuroplastic and neuroprotective neurotrophic factors.

Conclusion:

Therefore, it is suggested that physical exercise is an important neuroprotective modulator, bringing significant control of the disease and amplifying brain functions.

Panic disorder and cardiovascular diseases: an overview

The association between panic disorder (PD) and cardiovascular diseases (CVD) has been extensively studied in recent years and, although some studies have shown anxiety disorders co-existing or increasing the risk of heart disease, no causal hypothesis has been well established. Thus, a critical review was performed of the studies that evaluated the association between PD and cardiovascular diseases; synthesizing the evidence on the mechanisms mediators that theoretically would be the responsible for the causal pathway between PD and CVD, specifically. This overview shows epidemiological studies, and discusses biological mechanisms that could link PD to CVD, such as pleiotropy, heart rate variability, unhealthy lifestyle, atherosclerosis, mental stress, and myocardial perfusion defects. This study tried to provide a comprehensive narrative synthesis of previously published information regarding PD and CVD and open new possibilities of clinical management and pathophysiological understanding. Some epidemiological studies have indicated that PD could be a risk factor for CVD, raising morbidity and mortality in PD, suggesting an association between them. These studies argue that PD pathophysiology could cause or potentiate CVD. However, there is no evidence in favour of a causal relationship between PD and CVD. Therefore, PD patients with suspicions of cardiovascular symptoms need redoubled attention.

Relationship Among Physical Activity Level, Mood and Anxiety States and Quality of Life in Physical Education Students

BACKGROUND

Physical activity level (PAL) is known to play an important role in reducing risk factors associated with sedentarism, in addition to improving the mental health and health-related quality of life (HRQL).

OBJECTIVE

Investigate the relationship of PAL and their domains with HRQL, mood state (MS) and anxiety. Method: 140 Physical Education students (23.6 ± 3.7 years) were evaluated. The Baecke Habitual Physical Activity and Quality of Life (QOL-36) questionnaires, State-Trait Anxiety Inventories (STAI-S and STAI-T) and Profile of Mood States (POMS) scale were used to investigate PAL, HRQL and mental health indicators. Pearson's correlation coefficient examined the association between PAL and both mental health and HRQL parameters.

RESULTS

There was a correlation between state anxiety and both the domain leisure-time physical activity (LTPA) (p = 0.013) and total PAL score (p = 0.010). In relation to MS, a negative correlation was found between LTPA and total mood disorder (TMD) (p = 0.004). However, there were positive correlations between the vigor subscale and both LTPA (p=0.001) and total PAL (p=0.019). With respect to HRQL, analysis of the relationship between LTPA and total PAL demonstrated positive coefficients with the physical component summary (PCS) (p=0.000; p = 0.005), mental component summary (MCS) (p = 0.000; p = 0.006) and total HRQL (p = 0.000; p = 0.003).

CONCLUSION

The findings suggest that the rise in LTPA was related to an increase in HRQL and MS. However, PAL was positively related to anxiety.

Constitutive Activation of AKT2 in Humans Leads to Hypoglycemia Without Fatty Liver or Metabolic Dyslipidemia

Context

The activating p.Glu17Lys mutation in AKT2, a kinase mediating many of insulin's metabolic actions, causes hypoinsulinemic hypoglycemia and left-sided hemihypertrophy. The wider metabolic profile and longer-term natural history of the condition has not yet been reported.

Objective

To characterize the metabolic and cellular consequences of the AKT2 p.Glu17Lys mutation in two previously reported males at the age of 17 years.

Design and Intervention

Body composition analysis using dual-energy X-ray absorptiometry, overnight profiling of plasma glucose, insulin, and fatty acids, oral glucose tolerance testing, and magnetic resonance spectroscopy to determine hepatic triglyceride content was undertaken. Hepatic de novo lipogenesis was quantified using deuterium incorporation into palmitate. Signaling in dermal fibroblasts was studied ex vivo.

Results

Both patients had 37% adiposity. One developed hypoglycemia after 2 hours of overnight fasting with concomitant suppression of plasma fatty acids and ketones, whereas the other maintained euglycemia with an increase in free fatty acids. Blood glucose excursions after oral glucose were normal in both patients, albeit with low plasma insulin concentrations. In both patients, plasma triglyceride concentration, hepatic triglyceride content, and fasting hepatic de novo lipogenesis were normal. Dermal fibroblasts of one proband showed low-level constitutive phosphorylation of AKT and some downstream substrates, but no increased cell proliferation rate.

Conclusions

The p.Glu17Lys mutation of AKT2 confers low-level constitutive activity upon the kinase and produces hypoglycemia with suppressed fatty acid release from adipose tissue, but not fatty liver, hypertriglyceridemia, or elevated hepatic de novo lipogenesis. Hypoglycemia may spontaneously remit.

Hypoinsulinaemic, hypoketotic hypoglycaemia due to mosaic genetic activation of PI3-kinase

OBJECTIVE

Genetic activation of the insulin signal-transducing kinase AKT2 causes syndromic hypoketotic hypoglycaemia without elevated insulin. Mosaic activating mutations in class 1A phospatidylinositol-3-kinase (PI3K), upstream from AKT2 in insulin signalling, are known to cause segmental overgrowth, but the metabolic consequences have not been systematically reported. We assess the metabolic phenotype of 22 patients with mosaic activating mutations affecting PI3K, thereby providing new insight into the metabolic function of this complex node in insulin signal transduction.

METHODS

Three patients with megalencephaly, diffuse asymmetric overgrowth, hypoketotic, hypoinsulinaemic hypoglycaemia and no AKT2 mutation underwent further genetic, clinical and metabolic investigation. Signalling in dermal fibroblasts from one patient and efficacy of the mTOR inhibitor Sirolimus on pathway activation were examined. Finally, the metabolic profile of a cohort of 19 further patients with mosaic activating mutations in PI3K was assessed.

RESULTS

In the first three patients, mosaic mutations in PIK3CA (p.Gly118Asp or p.Glu726Lys) or PIK3R2 (p.Gly373Arg) were found. In different tissue samples available from one patient, the PIK3CA p.Glu726Lys mutation was present at burdens from 24% to 42%, with the highest level in the liver. Dermal fibroblasts showed increased basal AKT phosphorylation which was potently suppressed by Sirolimus. Nineteen further patients with mosaic mutations in PIK3CA had neither clinical nor biochemical evidence of hypoglycaemia.

CONCLUSIONS

Mosaic mutations activating class 1A PI3K cause severe non-ketotic hypoglycaemia in a subset of patients, with the metabolic phenotype presumably related to the extent of mosaicism within the liver. mTOR or PI3K inhibitors offer the prospect for future therapy.

Human biallelic MFN2 mutations induce mitochondrial dysfunction, upper body adipose hyperplasia, and suppression of leptin expression

MFN2 encodes mitofusin 2, a membrane-bound mediator of mitochondrial membrane fusion and inter-organelle communication. MFN2 mutations cause axonal neuropathy, with associated lipodystrophy only occasionally noted, however homozygosity for the p.Arg707Trp mutation was recently associated with upper body adipose overgrowth. We describe similar massive adipose overgrowth with suppressed leptin expression in four further patients with biallelic MFN2 mutations and at least one p.Arg707Trp allele. Overgrown tissue was composed of normal-sized, UCP1-negative unilocular adipocytes, with mitochondrial network fragmentation, disorganised cristae, and increased autophagosomes. There was strong transcriptional evidence of mitochondrial stress signalling, increased protein synthesis, and suppression of signatures of cell death in affected tissue, whereas mitochondrial morphology and gene expression were normal in skin fibroblasts. These findings suggest that specific MFN2 mutations cause tissue-selective mitochondrial dysfunction with increased adipocyte proliferation and survival, confirm a novel form of excess adiposity with paradoxical suppression of leptin expression, and suggest potential targeted therapies.

Insulin resistance uncoupled from dyslipidemia due to C-terminal PIK3R1 mutations

Obesity-related insulin resistance is associated with fatty liver, dyslipidemia, and low plasma adiponectin. Insulin resistance due to insulin receptor (INSR) dysfunction is associated with none of these, but when due to dysfunction of the downstream kinase AKT2 phenocopies obesity-related insulin resistance. We report 5 patients with SHORT syndrome and C-terminal mutations in PIK3R1, encoding the p85α/p55α/p50α subunits of PI3K, which act between INSR and AKT in insulin signaling. Four of 5 patients had extreme insulin resistance without dyslipidemia or hepatic steatosis. In 3 of these 4, plasma adiponectin was preserved, as in insulin receptor dysfunction. The fourth patient and her healthy mother had low plasma adiponectin associated with a potentially novel mutation, p.Asp231Ala, in adiponectin itself. Cells studied from one patient with the p.Tyr657X PIK3R1 mutation expressed abundant truncated PIK3R1 products and showed severely reduced insulin-stimulated association of mutant but not WT p85α with IRS1, but normal downstream signaling. In 3T3-L1 preadipocytes, mutant p85α overexpression attenuated insulin-induced AKT phosphorylation and adipocyte differentiation. Thus, PIK3R1 C-terminal mutations impair insulin signaling only in some cellular contexts and produce a subphenotype of insulin resistance resembling INSR dysfunction but unlike AKT2 dysfunction, implicating PI3K in the pathogenesis of key components of the metabolic syndrome.

C-terminal mutations in human PIK3R1 are associated with severe insulin resistance in the absence of dyslipidemia or hepatic steatosis.

Parkinson's Disease and Cognitive-Motor Dual-Task: Is Motor Prioritization Possible in the Early Stages of the Disease?

The authors aimed to compare the postural phase of gait initiation under single-task (gait initiation) and dual-task (gait initiation plus Stroop test) conditions in healthy subjects and in subjects with Parkinson's disease (PD) in the early stages (Hoehn and Yahr scale < 3). The postural phase of gait initiation was assessed through the centre of pressure in single and dual task in 10 healthy subjects and 9 with PD. The analysis indicated that in the early stages of PD, an additional cognitive task did not affect the displacement of the gait initiation. No significant effects occurred between the groups and within-subjects (p > .05). Also, no interaction was found between the groups and the conditions (single- and dual-task). Differences were found in the duration of the mediolateral postural phase (p = .003), which was higher in PD subjects than in healthy subjects. The findings suggest that subjects in the early stages of PD prioritize gait initiation, as their motor performance was similar to that of healthy subjects.

Cognitive predictors of balance in Parkinson's disease

Postural instability is one of the most incapacitating symptoms of Parkinson's disease (PD) and appears to be related to cognitive deficits. This study aims to determine the cognitive factors that can predict deficits in static and dynamic balance in individuals with PD. A sociodemographic questionnaire characterized 52 individuals with PD for this work. The Trail Making Test, Rule Shift Cards Test, and Digit Span Test assessed the executive functions. The static balance was assessed using a plantar pressure platform, and dynamic balance was based on the Timed Up and Go Test. The results were statistically analysed using SPSS Statistics software through linear regression analysis. The results show that a statistically significant model based on cognitive outcomes was able to explain the variance of motor variables. Also, the explanatory value of the model tended to increase with the addition of individual and clinical variables, although the resulting model was not statistically significant The model explained 25-29% of the variability of the Timed Up and Go Test, while for the anteroposterior displacement it was 23-34%, and for the mediolateral displacement it was 24-39%. From the findings, we conclude that the cognitive performance, especially the executive functions, is a predictor of balance deficit in individuals with PD.

Activity-Dependent Neurorehabilitation Beyond Physical Trainings: "Mental Exercise" Through Mirror Neuron Activation

The activity dependent brain repair mechanism has been widely adopted in many types of neurorehabilitation. The activity leads to target specific and non-specific beneficial effects in different brain regions, such as the releasing of neurotrophic factors, modulation of the cytokines and generation of new neurons in adult hood. However physical exercise program clinically are limited to some of the patients with preserved motor functions; while many patients suffered from paralysis cannot make such efforts. Here the authors proposed the employment of mirror neurons system in promoting brain rehabilitation by "observation based stimulation". Mirror neuron system has been considered as an important basis for action understanding and learning by mimicking others. During the action observation, mirror neuron system mediated the direct activation of the same group of motor neurons that are responsible for the observed action. The effect is clear, direct, specific and evolutionarily conserved. Moreover, recent evidences hinted for the beneficial effects on stroke patients after mirror neuron system activation therapy. Finally some music-relevant therapies were proposed to be related with mirror neuron system.

Influence of dual-task on sit-to-stand-to-sit postural control in Parkinson's disease

Postural control deficits are the most disabling aspects of Parkinson's disease (PD), resulting in decreased mobility and functional independence. The aim of this study was to assess the postural control stability, revealed by variables based on the centre of pressure (CoP), in individuals with PD while performing a sit-to-stand-to-sit sequence under single- and dual-task conditions. An observational, analytical and cross-sectional study was performed. The sample consisted of 9 individuals with PD and 9 healthy controls. A force platform was used to measure the CoP displacement and velocity during the sit-to-stand-to-sit sequence. The results were statistically analysed. Individuals with PD required greater durations for the sit-to-stand-to-sit sequence than the controls (p < 0.05). The anteroposterior and mediolateral CoP displacement were higher in the individuals with PD (p < 0.05). However, only the anteroposterior CoP velocity in the stand-to-sit phase (p = 0.006) was lower in the same individuals. Comparing the single- and dual-task conditions in both groups, the duration, the anteroposterior CoP displacement and velocity were higher in the dual-task condition (p < 0.05). The individuals with PD presented reduced postural control stability during the sit-to-stand-to-sit sequence, especially when under the dual-task condition. These individuals have deficits not only in motor performance, but also in cognitive performance when performing the sit-to-stand-to-sit sequence in their daily life tasks. Moreover, both deficits tend to be intensified when two tasks are performed simultaneously.

Effects of dual-task training on balance and executive functions in Parkinson's disease: A pilot study

The aim of this study was to analyze the efficacy of cognitive-motor dual-task training compared with single-task training on balance and executive functions in individuals with Parkinson's disease. Fifteen subjects, aged between 39 and 75 years old, were randomly assigned to the dual-task training group (n = 8) and single-task training group (n = 7). The training was run twice a week for 6 weeks. The single-task group received balance training and the dual-task group performed cognitive tasks simultaneously with the balance training. There were no significant differences between the two groups at baseline. After the intervention, the results for mediolateral sway with eyes closed were significantly better for the dual-task group and anteroposterior sway with eyes closed was significantly better for the single-task group. The results suggest superior outcomes for the dual-task training compared to the single-task training for static postural control, except in anteroposterior sway with eyes closed.

Hypomorphism in human NSMCE2 linked to primordial dwarfism and insulin resistance

Structural maintenance of chromosomes (SMC) complexes are essential for maintaining chromatin structure and regulating gene expression. Two the three known SMC complexes, cohesin and condensin, are important for sister chromatid cohesion and condensation, respectively; however, the function of the third complex, SMC5-6, which includes the E3 SUMO-ligase NSMCE2 (also widely known as MMS21) is less clear. Here, we characterized 2 patients with primordial dwarfism, extreme insulin resistance, and gonadal failure and identified compound heterozygous frameshift mutations in NSMCE2. Both mutations reduced NSMCE2 expression in patient cells. Primary cells from one patient showed increased micronucleus and nucleoplasmic bridge formation, delayed recovery of DNA synthesis, and reduced formation of foci containing Bloom syndrome helicase (BLM) after hydroxyurea-induced replication fork stalling. These nuclear abnormalities in patient dermal fibroblast were restored by expression of WT NSMCE2, but not a mutant form lacking SUMO-ligase activity. Furthermore, in zebrafish, knockdown of the NSMCE2 ortholog produced dwarfism, which was ameliorated by reexpression of WT, but not SUMO-ligase-deficient NSMCE. Collectively, these findings support a role for NSMCE2 in recovery from DNA damage and raise the possibility that loss of its function produces dwarfism through reduced tolerance of replicative stress.

Novel nanoaggregates with peripheric superparamagnetic iron oxide nanoparticles and organic cores through self-assembly of tailor-made block copolymers

Well-defined magnetic nanovesicles are obtained through self-assembly of double hydrophilic PEG–PDMAEMA block copolymers and oleic-coated iron oxide nanoparticles.

Synthesis of well-defined functionalized poly(2-(diisopropylamino)ethyl methacrylate) using ATRP with sodium dithionite as a SARA agent

2-(Diisopropylamino)ethyl methacrylate was polymerized by Atom Transfer Radical Polymerization using sodium dithionite as a reducing agent and supplemental activator with a Cu(ii)Br₂/Me₆TREN catalytic system.

Late endosomal transport and tethering are coupled processes controlled by RILP and the cholesterol sensor ORP1L

Late endosomes and lysosomes are dynamic organelles that constantly move and fuse to acquire cargo from early endosomes, phagosomes and autophagosome. Defects in lysosomal dynamics cause severe neurodegenerative and developmental diseases such as Niemann-Pick Type C disease and ARC syndrome, yet little is know about regulation of late endosomal fusion in a mammalian system. Mammalian endosomes destined for fusion need to be transported over very long distances before they tether to initiate contact. Here we describe that lysosomal tethering and transport are combined processes co-regulated by one multi-protein complex; RAB7-RILP-ORP1L. We show that RILP directly and concomitantly binds the tethering HOPS complex and the p150glued subunit of the dynein motor. ORP1L then functions as a cholesterol-sensing switch controlling RILP-HOPS-p150Glued interactions. We show that RILP and ORP1L control Ebola virus infection, a process dependent on late endosomal fusion. By combining recruitment and regulation of both the dynein motor and HOPS complex into a single multiprotein complex, the RAB7-RILP-ORP1L complex efficiently couples and times microtubule minus-end transport and fusion, two major events in endosomal biology.

Effect of the drying conditions on the microstructure of silica based xerogels and aerogels

Nanostructured silica based xerogels and aerogels are prepared by sol-gel technology, using methyltrimethoxysilane as precursor. The influence of the drying method and conditions on the microstructure of the obtained materials is investigated, since the drying stage has a critical influence on their porosity. Two types of drying methods were used: atmospheric pressure drying (evaporative), to produce xerogels, and supercritical fluids drying, to obtain aerogels. Although the supercritical fluids drying technique is more expensive and hazardous than the atmospheric pressure drying, it is well known that aerogels are less dense than the xerogels due to less pore shrinkage. However, the ideal situation would be to use atmospheric pressure drying in conditions that minimize the pore collapse. Therefore, in this work, different temperature cycles for atmospheric pressure drying and two heating rates for the supercritical fluids drying are tested to study the gels' shrinkage by analyzing the density and porosity properties of the final materials. The best materials obtained are aerogels dried with the lower heating rate (approximately 80 degrees C/h), since they exhibit very low bulk density (approximately 50 kg/m3), high porosity (95%)-mainly micro and mesopores, high surface area (approximately 500 m2/g), moderate flexibility and a remarkable hydrophobic character (>140 degrees). It was proved that the temperature cycles of atmospheric pressure drying can be tuned to obtain xerogels with properties comparable to those of aerogels, having a bulk density only approximately15 kg/m3 higher. All the synthesized materials fulfill the requirements for application as insulators in Space environments.

An activating mutation of AKT2 and human hypoglycemia

Pathological fasting hypoglycemia in humans is usually explained by excessive circulating insulin or insulin-like molecules or by inborn errors of metabolism impairing liver glucose production. We studied three unrelated children with unexplained, recurrent, and severe fasting hypoglycemia and asymmetrical growth. All were found to carry the same de novo mutation, p.Glu17Lys, in the serine/threonine kinase AKT2, in two cases as heterozygotes and in one case in mosaic form. In heterologous cells, the mutant AKT2 was constitutively recruited to the plasma membrane, leading to insulin-independent activation of downstream signaling. Thus, systemic metabolic disease can result from constitutive, cell-autonomous activation of signaling pathways normally controlled by insulin.

Founder effect in the Horn of Africa for an insulin receptor mutation that may impair receptor recycling

AIMS/HYPOTHESIS

Genetic insulin receptoropathies are a rare cause of severe insulin resistance. We identified the Ile119Met missense mutation in the insulin receptor INSR gene, previously reported in a Yemeni kindred, in four unrelated patients with Somali ancestry. We aimed to investigate a possible genetic founder effect, and to study the mechanism of loss of function of the mutant receptor.

METHODS

Biochemical profiling and DNA haplotype analysis of affected patients were performed. Insulin receptor expression in lymphoblastoid cells from a homozygous p.Ile119Met INSR patient, and in cells heterologously expressing the mutant receptor, was examined. Insulin binding, insulin-stimulated receptor autophosphorylation, and cooperativity and pH dependency of insulin dissociation were also assessed.

RESULTS

All patients had biochemical profiles pathognomonic of insulin receptoropathy, while haplotype analysis revealed the putative shared region around the INSR mutant to be no larger than 28 kb. An increased insulin proreceptor to β subunit ratio was seen in patient-derived cells. Steady state insulin binding and insulin-stimulated autophosphorylation of the mutant receptor was normal; however it exhibited decreased insulin dissociation rates with preserved cooperativity, a difference accentuated at low pH.

CONCLUSIONS/INTERPRETATION

The p.Ile119Met INSR appears to have arisen around the Horn of Africa, and should be sought first in severely insulin resistant patients with ancestry from this region. Despite collectively compelling genetic, clinical and biochemical evidence for its pathogenicity, loss of function in conventional in vitro assays is subtle, suggesting mildly impaired receptor recycling only.

Genetic defects in human pericentrin are associated with severe insulin resistance and diabetes

OBJECTIVE

Genetic defects in human pericentrin (PCNT), encoding the centrosomal protein pericentrin, cause a form of osteodysplastic primordial dwarfism that is sometimes reported to be associated with diabetes. We thus set out to determine the prevalence of diabetes and insulin resistance among patients with PCNT defects and examined the effects of pericentrin depletion on insulin action using 3T3-L1 adipocytes as a model system.

RESEARCH DESIGN AND METHODS

A cross-sectional metabolic assessment of 21 patients with PCNT mutations was undertaken. Pericentrin expression in human tissues was profiled using quantitative real-time PCR. The effect of pericentrin knockdown on insulin action and adipogenesis in 3T3-L1 adipocytes was determined using Oil red O staining, gene-expression analysis, immunoblotting, and glucose uptake assays. Pericentrin expression and localization also was determined in skeletal muscle.

RESULTS

Of 21 patients with genetic defects in PCNT, 18 had insulin resistance, which was severe in the majority of subjects. Ten subjects had confirmed diabetes (mean age of onset 15 years [range 5-28]), and 13 had metabolic dyslipidemia. All patients without insulin resistance were younger than 4 years old. Knockdown of pericentrin in adipocytes had no effect on proximal insulin signaling but produced a twofold impairment in insulin-stimulated glucose uptake, approximately commensurate with an associated defect in cell proliferation and adipogenesis. Pericentrin was highly expressed in human skeletal muscle, where it showed a perinuclear distribution.

CONCLUSIONS

Severe insulin resistance and premature diabetes are common features of PCNT deficiency but are not congenital. Partial failure of adipocyte differentiation may contribute to this, but pericentrin deficiency does not impair proximal insulin action in adipocytes.