Essentials
Potentially null homozygous Factor(F)7 nonsense mutations are associated to variable bleeding symptoms.
Readthrough of p.Ser112X (life‐threatening) and p.Cys132X (moderate) stop codons was ...investigated.
Readthrough‐mediated insertion of wild‐type or tolerated residues produce functional proteins.
Functional readthrough over homozygous F7 nonsense mutations contributes to the bleeding phenotype.
Summary
Background
Whereas the rare homozygous nonsense mutations causing factor (F)VII deficiency may predict null conditions that are almost completely incompatible with life, they are associated with appreciable differences in hemorrhagic symptoms. The misrecognition of premature stop codons (readthrough) may account for variable levels of functional full‐length proteins.
Objectives
To experimentally evaluate the basal and drug‐induced levels of FVII resulting from the homozygous p.Cys132X and p.Ser112X nonsense mutations that are associated with moderate (132X) or life‐threatening (112X) symptoms, and that are predicted to undergo readthrough with (132X) or without (112X) production of wild‐type FVII.
Methods
We transiently expressed recombinant FVII (rFVII) nonsense and missense variants in human embryonic kidney 293 cells, and evaluated secreted FVII protein and functional levels by ELISA, activated FX generation, and coagulation assays.
Results
The levels of functional FVII produced by p.Cys132X and p.Ser112X mutants (rFVII‐132X, 1.1% ± 0.2% of wild‐type rFVII; rFVII‐112X, 0.5% ± 0.1% of wild‐type rFVII) were compatible with the occurrence of spontaneous readthrough, which was magnified by the addition of G418 – up to 12% of the wild‐type value for the rFVII‐132X nonsense variant. The predicted missense variants arising from readthrough abolished (rFVII‐132Trp/Arg) or reduced (rFVII‐112Trp/Cys/Arg, 22–45% of wild‐type levels) secretion and function. These data suggest that the appreciable rescue of p.Cys132X function was driven by reinsertion of the wild‐type residue, whereas the minimal p.Ser112X function was explained by missense changes permitting FVII secretion and function.
Conclusions
The extent of functional readthrough might explain differences in the bleeding phenotype of patients homozygous for F7 nonsense mutations, and prevent null conditions even for the most readthrough‐unfavorable mutations.
Recent research into CO2 geological storage has shown that it has potential to be a safe and effective way to rapidly decrease short-term anthropogenic CO2 emissions. Despite this progress, ...stakeholders must be convinced that the scientific community has studied all possible scenarios, including a potential leak into the biosphere. To better understand the potential impact of such an event, a detailed geochemical and biological study was conducted during two different seasons on a naturally occurring gas vent located within a Mediterranean pasture ecosystem (Latera geothermal field, central Italy). Results from botanical, soil gas, and gas flux surveys, and from chemical and biological analyses of shallow soil samples (0-20 cm depth), show that a significant impact is only observed in the 6 m wide centre of the vent, where CO2 flux rates exceed 2000-3000 g m−2 d−1. In this "vent core" there is no vegetation, pH is low (minimum 3.5), and small changes are observed in mineralogy and bulk chemistry. In addition, microbial activities and populations are regulated in this interval by near-anoxic conditions, and by elevated soil gas CO2 (>95%) and trace reduced gases (CH4, H2S, and H2). An approximately 20 m wide halo surrounding the core forms a transition zone, over which there is a gradual decrease in CO2 concentrations, a rapid decrease in CO2 fluxes, and the absence of reactive gas species. In this transition zone grasses dominate near the vent core, but these are progressively replaced by clover and a greater plant diversity moving away from the vent centre. Physical parameters (e.g. pH, bulk chemistry, mineralogy) and microbial systems also gradually return to background values across this transition zone. Results indicate that, even at this anomalous high-flux site, the effects of the gas vent are spatially limited and that the ecosystem appears to have adapted to the different conditions through species substitution or adaptation.
Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder caused by the expression of mutant huntingtin protein (Htt). Suppression of Htt expression, using RNA interference, ...might be an effective therapy. However, if reduction of wild-type protein is not well tolerated in the brain, it may be necessary to suppress just the product of the mutant allele. We present a small interfering RNA (siRNA) that selectively reduces the endogenous mRNA for a heterozygous HD donor's pathogenic allele by approximately 80% by specifically targeting a single-nucleotide polymorphism (SNP) located several thousand bases downstream from the disease-causing mutation. In addition, we show selective suppression of endogenous mutant Htt protein, using this siRNA. We further present a method, using just a heterozygous patient's own mRNA, to determine which SNP variants correspond to the mutant allele. The method may be useful in any disorder in which a targeted SNP is far downstream from the pathogenic mutation. These results indicate that allele-specific treatment for Huntington's disease may be clinically feasible and practical.
•Conditions under which a contextual predictive model outperforms an un-contextual one in terms of misclassification costs.•If the unit of analysis is a single customer or a micro-segment, including ...context reduces the total cost.•If unit of analysis is a large segment or whole market, including context depends on dependent variable and cost of errors.•The finer the contextual information the stronger the effect of context on total cost.•The use of contextual predictive models depend on unity of analysis, dependent variable and costs of incorrect predictions.
The performance of customer behavior models depends on both the predictive accuracy and the cost of incorrect predictions. Previous research showed that including context in the customer behavior models can improve the accuracy. However, improving accuracy does not necessarily mean that the misclassification cost decreases. In fact, different errors have different costs. Even if the number of incorrect predictions decreases, the number of errors associated with higher costs increase. The aim of this paper is to understand whether including context in a predictive model reduces the misclassification costs and in which conditions this happens. Experimental analyses were done by varying the market granularity, the dependent variable and the context granularity. The results show that context leads to a decrease in the misclassification cost when the unit of analysis is the single customer or the micro-segment. The exceptions may occur when the unit of analysis is a segment. These findings have significant implications for companies that have to decide whether to gather context and how to exploit it best when they build predictive models of the behavior of their customers.
Telomeres interact with numerous proteins, including components of the shelterin complex, whose alteration, similarly to proliferation-induced telomere shortening, initiates cellular senescence. In ...tumors, telomere length is maintained by Telomerase activity or by the Alternative Lengthening of Telomeres mechanism, whose hallmark is the telomeric localization of the promyelocytic leukemia (PML) protein. Whether PML contributes to telomeres maintenance in normal cells is unknown. We show that in normal human fibroblasts the PML protein associates with few telomeres, preferentially when they are damaged. Proliferation-induced telomere attrition or their damage due to alteration of the shelterin complex enhances the telomeric localization of PML, which is increased in human T-lymphocytes derived from patients genetically deficient in telomerase. In normal fibroblasts, PML depletion induces telomere damage, nuclear and chromosomal abnormalities, and senescence. Expression of the leukemia protein PML/RARα in hematopoietic progenitors displaces PML from telomeres and induces telomere shortening in the bone marrow of pre-leukemic mice. Our work provides a novel view of the physiologic function of PML, which participates in telomeres surveillance in normal cells. Our data further imply that a diminished PML function may contribute to cell senescence, genomic instability, and tumorigenesis.
Aims To evaluate the cardiovascular risk associated with the presence of the Metabolic Syndrome in Type 2 diabetic subjects.
Methods Subjects with the Metabolic Syndrome, defined by WHO criteria, ...were identified in a large sample of non‐insulin‐treated Type 2 diabetic patients examined within the Verona Diabetes Complications Study (n = 946). At baseline and after a mean of 4.5 years follow‐up, cardiovascular disease (CVD) was assessed by medical history, physical examination, electrocardiogram (ECG) and echo‐duplex of carotid and lower limb arteries. Death certificates and medical records of subjects who died during the follow‐up were scrutinized in order to identify CVD deaths. In statistical analyses, CVD was considered as an aggregate end‐point, including fatal and non‐fatal coronary, cerebrovascular and peripheral vascular disease as well as ischaemic ECG abnormalities and vascular lesions at the echo‐duplex.
Results The proportion of subjects with the Metabolic Syndrome was very high (92.3%). At the baseline, 31.7% of subjects were coded positive for CVD, which was more prevalent in subjects with the Metabolic Syndrome (32.9 vs. 17.8%, P = 0.005). Among subjects free of CVD at the baseline (n = 559), CVD events during the follow‐up were significantly increased in patients with the Metabolic Syndrome as compared with those without it (19.9% vs. 3.9%, P < 0.001). Multiple logistic regression analysis showed that, along with sex, age, smoking and HbA1c, the presence of the Metabolic Syndrome independently predicted prevalent (OR 2.01, P = 0.045) and incident CVD (OR 4.89, P = 0.031).
Conclusions In Type 2 diabetes, the presence of the Metabolic Syndrome is associated with an almost 5‐fold increase in CVD risk.
•A new MCHP system is proposed using only renewable energy sources: CSP and biomass.•The system allows continuous production of electricity and heat over night and day.•A fluidized bed links heat ...from a Scheffler mirror and heat from biomass combustion.•The fluidized bed allows for a high heat transfer rate to the Stirling engine.
A new concept of a system based on a Stirling engine for the combined production of heat and electric power is presented. The system uses two renewable energy sources, direct solar (thermodynamic solar) and biomass (indirect solar energy). Biomass combustion is conducted using a fluidized bed combustor. A second source of energy, given by the direct irradiation of the bed with a concentrated solar radiation, is integrated in the same system, using the fluidized bed as solar receiver. A Scheffler type mirror is adopted to allow irradiation of the system in a fixed focal point. A Stirling engine, integrated into the fluidized bed, converts heat into electricity. Advantages of the proposed solution are illustrated and some preliminary results on the performance of the system, obtained with a simple model, are presented.
Reconstructed human epidermis is a useful tool for in vitro skin absorption studies of chemical compounds. If this may hold true also for topical dermatics, we investigated the glucocorticoid ...prednicarbate applied by two sets (innovator and generic) of cream, ointment and fatty ointment using the commercially available EpiDerm™ model. Moreover, stability and local tolerability of the preparations as well as drug release were studied, to estimate an influence on prednicarbate absorption and metabolism. While release ranked in the order cream
<
fatty ointment
<
ointment for both sets of preparations, prednicarbate penetration and permeation of the EpiDerm model did not. Less PC uptake observed with the generic ointment and fatty ointment appeared to be linked to impaired enzymatic ester cleavage within the tissue. Thus with drugs subject to skin metabolism, cutaneous uptake is not to be derived from drug release studies, yet has to be studied experimentally with viable skin or reconstructed human epidermis.
Carbon capture and storage (CCS) projects require an accurate evaluation of the sealing potential of faults and highly fractured zones to minimize the potential for CO2 leakage.
A study on the ...control exerted by fracture and fault networks on fluid flow, and in particular on CO2 leakage, should be based upon a representation of discrete fracture networks (DFN) that is as close as possible to that observed in the field. The present research integrates field work analysis, digital data representation, and fluid flow modeling to build a discrete fracture network (defined here as an Analogue Model; AM) that preserves the field-observed fracture geometry and relative proportion of the associated petrophysical parameters (aperture, length, direction and dip). Our study area is an outcrop in the caldera of Latera (Central Italy) where CO2 is naturally released and gas discharge in the atmosphere can be directly observed.
We then compare the AM results to those generated by inputting the same fracture parameters into commercial DFN models. Our results highlight that these latter generally underestimate permeability values (by about two orders of magnitude) and hide fault-related anisotropies observed in the field, which instead are very well defined by the AM. The models were applied to a study site in the Latera caldera (Central Italy), where geologically produced CO2 leaks to the atmosphere along an exposed fault, and to simulate gas release through a fractured reservoir. Simulated leakage correlates well with field measurements that show CO2 spot anomalies at fault and fracture intersections and indicate how gas migration pathways are controlled by discontinuity permeability, complex fracture orientations, and fracture positions within the analyzed rock volume.
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