30 research outputs found
A Common Polymorphism in the Promoter of UCP2 Contributes to the Variation in Insulin Secretion in Glucose-Tolerant Subjects
It was reported that the common −866G/A polymorphism in the promoter of the human uncoupling protein-2 (UCP2) gene, which enhances its trascriptional activity, is associated with increased mRNA levels in human adipocytes and reduced risk of obesity. Studies in knockout mice and β-cells indicate that UCP2 may play a role in β-cell function. In this study, we addressed the question of whether the common −866G/A polymorphism in UCP2 gene contributes to the variation of insulin secretion in humans by genotyping 301 nondiabetic subjects who underwent an oral glucose tolerance test. Glucose-stimulated insulin secretion estimated by several indexes of β-cell function was significantly lower in carriers of the −866A/A genotype compared with −866A/G or −866G/G according to the dosage of the A allele (P = 0.002–0.05). To investigate directly whether the UCP2 −866G/A polymorphism affects human islet function, pancreatic islets isolated from two −866G/G homozygous, seven −866G/A heterozygous, and one −866A/A homozygous nondiabetic donors were studied. Islets from −866A/A homozygous had lower insulin secretion in response to glucose stimulation as compared with −866G/G and −866G/A carriers. These results indicate that the common −866G/A polymorphism in the UCP2 gene may contribute to the biological variation of insulin secretion in humans
Hypoglycemia Assessed by Continuous Glucose Monitoring Is Associated with Preclinical Atherosclerosis in Individuals with Impaired Glucose Tolerance
Hypoglycemia is associated with increased risk of cardiovascular adverse clinical outcomes. There is evidence that impaired glucose tolerance (IGT) is associated with cardiovascular morbidity and mortality. Whether IGT individuals have asymptomatic hypoglycemia under real-life conditions that are related to early atherosclerosis is unknown. To this aim, we measured episodes of hypoglycemia during continuous interstitial glucose monitoring (CGM) and evaluated their relationship with early manifestation of vascular atherosclerosis in glucose tolerant and intolerant individuals. An oral glucose tolerance test (OGTT) was performed in 79 non-diabetic subjects. Each individual underwent continuous glucose monitoring for 72 h. Cardiovascular risk factors and ultrasound measurement of carotid intima-media thickness (IMT) were evaluated. IGT individuals had a worse cardiovascular risk profile, including higher IMT, and spent significantly more time in hypoglycemia than glucose-tolerant individuals. IMT was significantly correlated with systolic (r = 0.22; P = 0.05) and diastolic blood pressure (r = 0.28; P = 0.01), total (r = 0.26; P = 0.02) and LDL cholesterol (r = 0.27; P = 0.01), 2-h glucose (r = 0.39; P<0.0001), insulin sensitivity (r = −0.26; P = 0.03), and minutes spent in hypoglycemia (r = 0.45; P<0.0001). In univariate analyses adjusted for gender, minutes spent in hypoglycemia were significantly correlated with age (r = 0.26; P = 0.01), waist circumference (r = 0.33; P = 0.003), 2-h glucose (r = 0.58; P<0.0001), and 2-h insulin (r = 0.27; P = 0.02). In a stepwise multivariate regression analysis, the variables significantly associated with IMT were minutes spent in hypoglycemia (r2 = 0.252; P<0.0001), and ISI index (r2 = 0.089; P = 0.004), accounting for 34.1% of the variation. Episodes of hypoglycemia may be considered as a new potential cardiovascular risk factor for IGT individuals
A Survey on Design Methodologies for Accelerating Deep Learning on Heterogeneous Architectures
In recent years, the field of Deep Learning has seen many disruptive and
impactful advancements. Given the increasing complexity of deep neural
networks, the need for efficient hardware accelerators has become more and more
pressing to design heterogeneous HPC platforms. The design of Deep Learning
accelerators requires a multidisciplinary approach, combining expertise from
several areas, spanning from computer architecture to approximate computing,
computational models, and machine learning algorithms. Several methodologies
and tools have been proposed to design accelerators for Deep Learning,
including hardware-software co-design approaches, high-level synthesis methods,
specific customized compilers, and methodologies for design space exploration,
modeling, and simulation. These methodologies aim to maximize the exploitable
parallelism and minimize data movement to achieve high performance and energy
efficiency. This survey provides a holistic review of the most influential
design methodologies and EDA tools proposed in recent years to implement Deep
Learning accelerators, offering the reader a wide perspective in this rapidly
evolving field. In particular, this work complements the previous survey
proposed by the same authors in [203], which focuses on Deep Learning hardware
accelerators for heterogeneous HPC platforms
Levofloxacin-induced hemichorea-hemiballism in a patient with previous thalamic infarction
[no abstract available
CIDP, CMT1B, or CMT1B plus CIDP?
Charcot-Marie-Tooth disease type 1 (CMT1) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have distinct clinical and neurophysiological features that result from dysmyelination in CMT1 and macrophage-mediated segmental demyelination in CIDP. CMT1 may occur in genetically isolated cases with atypical presentations that converge phenotypically with CIDP; in rare cases, however, CMT1 may be complicated by superimposed CIDP. We report the case of a patient harboring a de novo heterozygous null mutation of the myelin protein zero (MPZ) gene and affected by subclinical CMT1B who became symptomatic due to superimposed CIDP. Peripheral nerve high-resolution ultrasound (HRUS) aided in establishing the coexistence of CMT1B and CIDP; the diagnosis was further supported by favorable clinical, neurophysiological, and ultrasound responses to immunoglobulin therapy
Hypothalamic-Bulbar MRI hyperintensity in Anti-IgLON5 disease with serum-restricted antibodies: a case report and systematic review of literature
Anti-IgLON5 disease is a rare neurodegenerative tauopathy that displays heterogeneity in clinical spectrum, disease course, cerebrospinal fluid (CSF) findings, and variable response to immunotherapy. Sleep disorders, bulbar dysfunction, and gait abnormalities are common presenting symptoms, and conventional brain MRI scanning is often unrevealing
Towards Chemotactic Supramolecular Nanoparticles: From Autonomous Surface Motion Following Specific Chemical Gradients to Multivalency-Controlled Disassembly
Nature designs chemotactic supramolecular
structures that can selectively bind specific groups present on surfaces, autonomously
scan them moving along density gradients, and react once a critical
concentration is encountered. While such properties
are key in many biological functions, these also offer inspirations for
designing artificial systems capable of similar bioinspired autonomous
behaviors. One approach is to use soft molecular units that self-assemble in
aqueous solution generating nanoparticles (NPs) that display specific chemical
groups on their surface, enabling for multivalent interactions with
complementarily functionalized surfaces. However, a first challenge is to
explore the behavior of these assemblies at sufficiently high-resolution to
gain insights on the molecular factors controlling their behaviors. Here we
show that, coupling coarse-grained molecular models and advanced simulation
approaches, it is possible to study the (autonomous or driven) motion of
self-assembled NPs on a receptor-grafted surface at submolecular resolution. As
an example, we focus on self-assembled NPs composed of facially amphiphilic
oligomers. We observe how tuning the multivalent interactions between the NP
and the surface allows to control NP binding, its diffusion along chemical
surface gradients, and ultimately, the NP reactivity at determined surface
group densities. In silico experiments provide physical-chemical
insights on key molecular features in the self-assembling units which determine
the dynamic behavior and fate of the NPs on the surface: from adhesion, to
diffusion, and disassembly. This offers a privileged point of view into the
chemotactic properties of supramolecular assemblies, improving our knowledge on
how to design new types of materials with bioinspired autonomous behaviors.</p