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The Effects of Cholecalciferol Supplementation on Vitamin D Status Among a Diverse Population of Collegiate Basketball Athletes: A Quasi-Experimental Trial
Nutrients 2020, 12(2), 370; https://doi.org/10.3390/nu12020370 (registering DOI) - 31 Jan 2020
Abstract
Vitamin D may play a role in performance and injury risk, yet the required supplementation dosage for collegiate athletes is unclear. The objective of this study was to define the dosage of vitamin D3 supplementation required to beneficially affect serum 25-hydroxyvitamin D [...] Read more.
Vitamin D may play a role in performance and injury risk, yet the required supplementation dosage for collegiate athletes is unclear. The objective of this study was to define the dosage of vitamin D3 supplementation required to beneficially affect serum 25-hydroxyvitamin D (25(OH)D) among a sample of collegiate basketball athletes. This was a quasi-experimental trial, participants were allocated to one of three groups of vitamin D3 daily at the beginning of pre-season training and dependent upon their baseline vitamin D status as follows: insufficient (<75 nmol/L) to 10,000 IU, sufficient (75–125 nmol/L) to 5000 IU and optimal (>125 nmol/L) to no supplementation. Follow-up assessments were completed ~ 5 months later in post season. The majority (n = 13) were allocated to 10,000 IU vs. n = 5 to 5000 IU and n = 2 to no supplementation. The 10,000 IU group showed the greatest change (35.0 ± 27.0 nmol/L) vs. the 5000 IU group (−9.3 ± 9.6 nmol/L) and no supplementation group (−41.6 ± 11.7 nmol/L, p < 0.01). Only 1 participant reached optimal status in the 10,000 IU group. In conclusion, a daily dosage of 10,000 IU vitamin D3 supplementation mitigated the high prevalence of vitamin D deficiency among collegiate basketball players but was insufficient for all to reach sufficient levels. Full article
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Open AccessArticle
C-Terminal Domain of the Human Zinc Transporter hZnT8 Is Structurally Indistinguishable from Its Disease Risk Variant (R325W)
Int. J. Mol. Sci. 2020, 21(3), 926; https://doi.org/10.3390/ijms21030926 (registering DOI) - 31 Jan 2020
Abstract
The human zinc transporter 8 (hZnT8) plays important roles in the storage of insulin in the secretory vesicles of pancreatic β cells. hZnT8 consists of a transmembrane domain, with its N- and C-termini protruding into the cytoplasm. Interestingly, the exchange of arginine to [...] Read more.
The human zinc transporter 8 (hZnT8) plays important roles in the storage of insulin in the secretory vesicles of pancreatic β cells. hZnT8 consists of a transmembrane domain, with its N- and C-termini protruding into the cytoplasm. Interestingly, the exchange of arginine to tryptophan at position 325 in the C-terminal domain (CTD) increases the risk of developing type 2 diabetes mellitus (T2D). In the present study, the CTDs of hZnT8 (the wild-type (WT) and its disease risk variant (R325W)) were expressed, purified, and characterized in their native forms by biophysical techniques. The data reveal that the CTDs form tetramers which are stabilized by zinc binding, and exhibit negligible differences in their secondary structure content and zinc-binding affinities in solution. These findings provide the basis for conducting further structural studies aimed at unravelling the molecular mechanism underlying the increased susceptibility to develop T2D, which is modulated by the disease risk variant. Full article
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Open AccessArticle
High-Efficiency Metasurfaces with 2π Phase Control Based on Aperiodic Dielectric Nanoarrays
Nanomaterials 2020, 10(2), 250; https://doi.org/10.3390/nano10020250 (registering DOI) - 31 Jan 2020
Abstract
In this study, the high-efficiency phase control Si metasurfaces are investigated based on aperiodic nanoarrays unlike widely-used period structures, the aperiodicity of which providing additional freedom to improve metasurfaces’ performance. Firstly, the phase control mechanism of Huygens nanoblocks is demonstrated, particularly the internal [...] Read more.
In this study, the high-efficiency phase control Si metasurfaces are investigated based on aperiodic nanoarrays unlike widely-used period structures, the aperiodicity of which providing additional freedom to improve metasurfaces’ performance. Firstly, the phase control mechanism of Huygens nanoblocks is demonstrated, particularly the internal electromagnetic resonances and the manipulation of effective electrical/magnetic polarizabilities. Then, a group of high-transmission Si nanoblocks with 2π phase control is sought by sweeping the geometrical parameters. Finally, several metasurfaces, such as grating and parabolic lens, are numerically realized by the nanostructures with high efficiency. The conversion efficiency of the grating reaches 80%, and the focusing conversion efficiency of the metalens is 99.3%. The results show that the high-efficiency phase control metasurfaces can be realized based on aperiodic nanoarrays, i.e., additional design freedom. Full article
Open AccessArticle
Elongator Subunit 3 (Elp3) Is Required for Zebrafish Trunk Development
Int. J. Mol. Sci. 2020, 21(3), 925; https://doi.org/10.3390/ijms21030925 (registering DOI) - 31 Jan 2020
Abstract
Transfer RNAs (tRNAs) are the most post-transcriptionally modified RNA species. Some of these modifications, especially the ones located in the anti-codon loop, are required for decoding capabilities of tRNAs. Such is the case for 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U), synthetized by the [...] Read more.
Transfer RNAs (tRNAs) are the most post-transcriptionally modified RNA species. Some of these modifications, especially the ones located in the anti-codon loop, are required for decoding capabilities of tRNAs. Such is the case for 5-methoxy-carbonyl-methyl-2-thio-uridine (mcm5s2U), synthetized by the Elongator complex. Mutants for its sub-units display pleiotropic phenotypes. In this paper, we analyze the role of elp3 (Elongator catalytic sub-unit) in zebrafish development. We found that it is required for trunk development; elp3 knock-down animals presented diminished levels of mcm5s2U and sonic hedgehog (Shh) signaling activity. Activation of this pathway was sufficient to revert the phenotype caused by elp3 knockdown, indicating a functional relationship between Elongator and Shh through a yet unknown molecular mechanism. Full article
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Open AccessArticle
Impact of Prevalence Ratios of Chondroitin Sulfate (CS)- 4 and -6 Isomers Derived from Marine Sources in Cell Proliferation and Chondrogenic Differentiation Processes
Mar. Drugs 2020, 18(2), 94; https://doi.org/10.3390/md18020094 (registering DOI) - 31 Jan 2020
Abstract
Osteoarthritis is the most prevalent rheumatic disease. During disease progression, differences have been described in the prevalence of chondroitin sulfate (CS) isomers. Marine derived-CS present a higher proportion of the 6S isomer, offering therapeutic potential. Accordingly, we evaluated the effect of exogenous supplementation [...] Read more.
Osteoarthritis is the most prevalent rheumatic disease. During disease progression, differences have been described in the prevalence of chondroitin sulfate (CS) isomers. Marine derived-CS present a higher proportion of the 6S isomer, offering therapeutic potential. Accordingly, we evaluated the effect of exogenous supplementation of CS, derived from the small spotted catshark (Scyliorhinus canicula), blue shark (Prionace glauca), thornback skate (Raja clavata) and bovine CS (reference), on the proliferation of osteochondral cell lines (MG-63 and T/C-28a2) and the chondrogenic differentiation of mesenchymal stromal cells (MSCs). MG-G3 proliferation was comparable between R. clavata (CS-6 intermediate ratio) and bovine CS (CS-4 enrichment), for concentrations below 0.5 mg/mL, defined as a toxicity threshold. T/C-28a2 proliferation was significantly improved by intermediate ratios of CS-6 and -4 isomers (S. canicula and R. clavata). A dose-dependent response was observed for S. canicula (200 µg/mL vs 50 and 10 µg/mL) and bovine CS (200 and 100 µg/mL vs 10 µg/mL). CS sulfation patterns discretely affected MSCs chondrogenesis; even though S. canicula and R. clavata CS up-regulated chondrogenic markers expression (aggrecan and collagen type II) these were not statistically significant. We demonstrate that intermediate values of CS-4 and -6 isomers improve cell proliferation and offer potential for chondrogenic promotion, although more studies are needed to elucidate its mechanism of action. Full article
Open AccessArticle
Linking Environmental Regulation and Financial Performance: The Mediating Role of Green Dynamic Capability and Sustainable Innovation
Sustainability 2020, 12(3), 1007; https://doi.org/10.3390/su12031007 (registering DOI) - 31 Jan 2020
Abstract
This study develops a multiple mediating model for exploring the link between environmental regulation and financial performance through green dynamic capability, sustainability exploration/exploitation innovation, based on the data from 355 Chinese manufacturing firms. Empirical results support a mediating role of green dynamic capability [...] Read more.
This study develops a multiple mediating model for exploring the link between environmental regulation and financial performance through green dynamic capability, sustainability exploration/exploitation innovation, based on the data from 355 Chinese manufacturing firms. Empirical results support a mediating role of green dynamic capability and sustainability exploration/exploitation in the link between environmental regulation and financial performance, respectively. What’s more, our findings indicate that environmental regulation can help improve financial performance via two multiple mediating paths, i.e., green dynamic capability and sustainability exploration innovation, as well as green dynamic capability and sustainability exploitation innovation. These key findings will help to understand how important green dynamic capability and sustainable innovation is when Chinese manufacturing firms establish a business-politics tie. Full article
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Open AccessArticle
Key Audit Matters for Production-to-Order Industry and Conservatism
Int. J. Financial Stud. 2020, 8(1), 5; https://doi.org/10.3390/ijfs8010005 (registering DOI) - 30 Jan 2020
Abstract
In this study, the effects of key audit matters (KAMs), one of the measures recently introduced to improve accounting transparency in the production-to-order industry in terms of corporate sustainability, are examined. After the introduction of KAMs, auditors should publicly disclose key audit matters [...] Read more.
In this study, the effects of key audit matters (KAMs), one of the measures recently introduced to improve accounting transparency in the production-to-order industry in terms of corporate sustainability, are examined. After the introduction of KAMs, auditors should publicly disclose key audit matters that had been internally judged in the past. In cases where these are missing or misunderstood, the range of the auditor’s liability may increase. Thus, from the viewpoint of the auditor, the description of KAMs can be recognized as the disclosure of internal judgments and an increase in the risk of litigation. It is judged that, to this end, auditors will perform their auditing work more conservatively in cases where they should describe KAMs. The results of analysis of companies to which KAMs are applied indicate that auditors carried out audits more conservatively for such companies. As such, the result can be interpreted as indicating that, due to the introduction of KAMs, auditors evaluate their risk highly and carry out audits more conservatively in order to reduce the risk. This study is meaningful in that it empirically analyzes the effects of the introduction of the recently implemented KAMs. In addition, this study provides implications for enterprises that prepare financial statements, supervisory institutions that conduct supervision, auditors, and capital market participants, as it presents the finding that, with the introduction of KAMs, auditors perform their work with more conservative perspectives. In addition, the findings of this study provide a basis for future studies on KAMs. Full article
Open AccessArticle
The Impact of Thailand's Openness on Bilateral Trade between Thailand and Japan: Copula-Based Markov Switching Seemingly Unrelated Regression Model
Economies 2020, 8(1), 9; https://doi.org/10.3390/economies8010009 - 30 Jan 2020
Abstract
The purpose of this paper is to analyze the impact of trade openness and the factors based on the gravity model on the bilateral trade flows between Thailand and Japan. The factors consist of GDP, distance, trade openness, and exchange rate. Bilateral trade [...] Read more.
The purpose of this paper is to analyze the impact of trade openness and the factors based on the gravity model on the bilateral trade flows between Thailand and Japan. The factors consist of GDP, distance, trade openness, and exchange rate. Bilateral trade is composed of two flows: Thailand’s export flow to Japan, and Thailand’s import flow from Japan. The specified gravity equations are estimated by Copula-based Markov switching seemingly unrelated regression approach. The best-fitting model is chosen based on the lowest Akaike information criterion (AIC) and Bayesian information criterion (BIC). The Normal and Student's t distributions are for Thailand’s export equation and Thailand’s import equation, respectively. The Student's t copula is applied for joint distribution. Analyzing the bilateral trade flow is separated into two situations, namely the high and the low growth markets. Empirical results show that distance provides a positive effect on the export in a high growth regime, but a negative impact on the export in a low growth regime. As for Thailand’s import flow, all variables, but especially trade openness, provide strong evidence supporting significance for both regimes. For the GDPs of both Thailand and Japan, trade openness and the exchange rate increase import flow in a high growth market. Meanwhile, the exchange rate decreases import flow in a low growth market. The Markov Switching Probability Estimation notes that Thailand’s trading with Japan is mostly in the fast-growing market. Full article
Open AccessFeature PaperArticle
General Conditions of Weak Convergence of Discrete-Time Multiplicative Scheme to Asset Price with Memory
Risks 2020, 8(1), 11; https://doi.org/10.3390/risks8010011 (registering DOI) - 30 Jan 2020
Abstract
We present general conditions for the weak convergence of a discrete-time additive scheme to a stochastic process with memory in the space $D [ 0 , T ]$ . Then we investigate the convergence of the related multiplicative scheme to a process that [...] Read more.
We present general conditions for the weak convergence of a discrete-time additive scheme to a stochastic process with memory in the space $D [ 0 , T ]$ . Then we investigate the convergence of the related multiplicative scheme to a process that can be interpreted as an asset price with memory. As an example, we study an additive scheme that converges to fractional Brownian motion, which is based on the Cholesky decomposition of its covariance matrix. The second example is a scheme converging to the Riemann–Liouville fractional Brownian motion. The multiplicative counterparts for these two schemes are also considered. As an auxiliary result of independent interest, we obtain sufficient conditions for monotonicity along diagonals in the Cholesky decomposition of the covariance matrix of a stationary Gaussian process. Full article
(This article belongs to the Special Issue Stochastic Modelling in Financial Mathematics)
Open AccessArticle
Add-On Type Pulse Charger for Quick Charging Li-Ion Batteries
Electronics 2020, 9(2), 227; https://doi.org/10.3390/electronics9020227 - 30 Jan 2020
Abstract
In this paper, an add-on type pulse charger is proposed to shorten the charging time of a lithium ion battery. To evaluate the performance of the proposed pulse charge method, an add-on type pulse charger prototype is designed and implemented. Pulse charging is [...] Read more.
In this paper, an add-on type pulse charger is proposed to shorten the charging time of a lithium ion battery. To evaluate the performance of the proposed pulse charge method, an add-on type pulse charger prototype is designed and implemented. Pulse charging is applied to 18650 cylindrical lithium ion battery packs with 10 series and 2 parallel structures. The proposed pulse charger is controlled by pulse duty, frequency and magnitude. Various experimental conditions are applied to optimize the charging parameters of the pulse charging technique. Battery charging data are analyzed according to the current magnitude and duty at 500 Hz and 1000 Hz and 2000 Hz frequency conditions. The proposed system is similar to the charging speed of the constant current method under new battery conditions. However, it was confirmed that as the battery performance is degraded, the charging speed due to pulse charging increases. Thus, in applications where battery charging/discharging occurs frequently, the proposed pulse charger has the advantage of fast charging in the long run over conventional constant current (CC) chargers. Full article
(This article belongs to the Special Issue Power Converters in Power Electronics)
Open AccessFeature PaperArticle
Buoyancy Driven Flow with Gas-Liquid Coatings of Peristaltic Bubbly Flow in Elastic Walls
Coatings 2020, 10(2), 115; https://doi.org/10.3390/coatings10020115 - 30 Jan 2020
Abstract
In this paper, liquid coatings of bubbly flow with peristaltic motion inside elastic walls is investigated. The proposed model is constructed using the two-fluid approach with the most distinctive collaboration among gas, fluid, pressure, and drag forces. Variation in pressure leads to a [...] Read more.
In this paper, liquid coatings of bubbly flow with peristaltic motion inside elastic walls is investigated. The proposed model is constructed using the two-fluid approach with the most distinctive collaboration among gas, fluid, pressure, and drag forces. Variation in pressure leads to a change in void fraction. The differential controlling conditions affected by the long wavelength of the peristaltic wave and the slow movement are taken into account. Analytical results of the simplified governing equations are obtained using the homotopy perturbation method (HPM). The features of the significant parameters are shown and examined graphically. Full article
(This article belongs to the Special Issue Recent Trends in Coatings and Thin Film–Modeling and Application)
Open AccessFeature PaperArticle
Eudragit S100 Entrapped Liposome for Curcumin Delivery: Anti-Oxidative Effect in Caco-2 Cells
Coatings 2020, 10(2), 114; https://doi.org/10.3390/coatings10020114 - 30 Jan 2020
Abstract
Curcumin is a natural polyphenol with strong antioxidant activity. However, this molecule shows a very poor bioavailability, instability, and rapid metabolism in vivo. In this work curcumin was loaded in Eudragit-coated liposomes to create a gastroresistant carrier, able to protect its load from [...] Read more.
Curcumin is a natural polyphenol with strong antioxidant activity. However, this molecule shows a very poor bioavailability, instability, and rapid metabolism in vivo. In this work curcumin was loaded in Eudragit-coated liposomes to create a gastroresistant carrier, able to protect its load from degradation and free it at the site of absorption in the colon region. Small unilamellar vesicles were prepared and coated with Eudragit by a pH-driven method. The physico-chemical properties of the prepared systems were assessed by light scattering, transmission electron microscopy, infrared spectroscopy, and differential scanning calorimetry. The uptake of vesicles by Caco-2 cells and the anti-oxidant activity in cells were evaluated. The produced vesicles showed dimensions of about forty nanometers that after covering with Eudragit resulted to have micrometric dimensions at acid pH. The experiments showed that at pH > 7.0 the polymeric coating dissolves, releasing the nanometric liposomes and allowing them to enter Caco-2 cells. Delivered curcumin loaded vesicles were then able to decrease significantly ROS levels as induced by H2O2 in Caco-2 cells. The proposed work showed the possibility of realizing effective gastroresistant curcumin liposome formulations for the delivery of antioxidant molecules to Caco-2 cells, potentially applicable to the treatment of pathological conditions related to intestinal oxidative stress. Full article
(This article belongs to the Special Issue Surfaces Modification and Analysis for Innovative Biomaterials)
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Open AccessFeature PaperArticle
Pure Sn Coatings Produced by Pulse Plating from Stannate Bath
Coatings 2020, 10(2), 117; https://doi.org/10.3390/coatings10020117 (registering DOI) - 30 Jan 2020
Abstract
We have produced pure Sn coatings from an alkaline bath plating. The plating bath was composed of sodium stannate and sodium hydroxide with sorbitol as an additive. The experiments were performed with a potentiostat/galvanostat at various current densities from 5–25 mA/cm2. [...] Read more.
We have produced pure Sn coatings from an alkaline bath plating. The plating bath was composed of sodium stannate and sodium hydroxide with sorbitol as an additive. The experiments were performed with a potentiostat/galvanostat at various current densities from 5–25 mA/cm2. The morphology of the coatings, thickness, plating rate, and microhardness were evaluated. Furthermore the wetting of the Sn coatings on a Cu substrate was also assessed by area spread ratio measurements after reflow at 250 °C. The resultant coatings were very smooth and shiny. Initially, the plating morphology was uneven and a nodular type, which further improved with increasing current density up to 15 mA/cm2. The plating rate and thickness were the maximum at a current density of 15 mA/cm2. The coatings had higher strength and solderability at 15 mA/cm2 due to the improved microstructure and plating rate. Full article
Open AccessFeature PaperArticle
Structural Determinants Responsible for the Preferential Insertion of Ribonucleotides by Bacterial NHEJ PolDom
Biomolecules 2020, 10(2), 203; https://doi.org/10.3390/biom10020203 - 30 Jan 2020
Abstract
The catalytic active site of the Polymerization Domain (PolDom) of bacterial Ligase D is designed to promote realignments of the primer and template strands and extend mispaired 3′ ends. These features, together with the preferred use of ribonucleotides (NTPs) over deoxynucleotides [...] Read more.
The catalytic active site of the Polymerization Domain (PolDom) of bacterial Ligase D is designed to promote realignments of the primer and template strands and extend mispaired 3′ ends. These features, together with the preferred use of ribonucleotides (NTPs) over deoxynucleotides (dNTPs), allow PolDom to perform efficient double strand break repair by nonhomologous end joining when only a copy of the chromosome is present and the intracellular pool of dNTPs is depleted. Here, we evaluate (i) the role of conserved histidine and serine/threonine residues in NTP insertion, and (ii) the importance in the polymerization reaction of a conserved lysine residue that interacts with the templating nucleotide. To that extent, we have analyzed the biochemical properties of variants at the corresponding His651, Ser768, and Lys606 of Pseudomonas aeruginosa PolDom (Pa-PolDom). The results show that preferential insertion of NMPs is principally due to the histidine that also contributes to the plasticity of the active site to misinsert nucleotides. Additionally, Pa-PolDom Lys606 stabilizes primer dislocations. Finally, we show that the active site of PolDom allows the efficient use of 7,8-dihydro-8-oxo-riboguanosine triphosphate (8oxoGTP) as substrate, a major nucleotide lesion that results from oxidative stress, inserting with the same efficiency both the anti and syn conformations of 8oxoGMP. Full article
Open AccessArticle
Binder-Free V2O5 Cathode for High Energy Density Rechargeable Aluminum-Ion Batteries
Nanomaterials 2020, 10(2), 247; https://doi.org/10.3390/nano10020247 (registering DOI) - 30 Jan 2020
Abstract
Nowadays, research on electrochemical storage systems moves into the direction of post-lithium-ion batteries, such as aluminum-ion batteries, and the exploration of suitable materials for such batteries. Vanadium pentoxide (V2O5) is one of the most promising host materials for the [...] Read more.
Nowadays, research on electrochemical storage systems moves into the direction of post-lithium-ion batteries, such as aluminum-ion batteries, and the exploration of suitable materials for such batteries. Vanadium pentoxide (V2O5) is one of the most promising host materials for the intercalation of multivalent ions. Here, we report on the fabrication of a binder-free and self-supporting V2O5 micrometer-thick paper-like electrode material and its use as the cathode for rechargeable aluminum-ion batteries. The electrical conductivity of the cathode was significantly improved by a novel in-situ and self-limiting copper migration approach into the V2O5 structure. This process takes advantage of the dissolution of Cu by the ionic liquid-based electrolyte, as well as the presence of two different accommodation sites in the nanostructured V2O5 available for aluminum-ions and the migrated Cu. Furthermore, the advanced nanostructured cathode delivered a specific discharge capacity of up to ~170 mAh g−1 and the reversible intercalation of Al3+ for more than 500 cycles with a high Coulomb efficiency reaching nearly 100%. The binder-free concept results in an energy density of 74 Wh kg−1, which shows improved energy density in comparison to the so far published V2O5-based cathodes. Our results provide valuable insights for the future design and development of novel binder-free and self-supporting electrodes for rechargeable multivalent metal-ion batteries associating a high energy density, cycling stability, safety and low cost. Full article
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Open AccessArticle
Saliva Diagnosis as a Disease Predictor
J. Clin. Med. 2020, 9(2), 377; https://doi.org/10.3390/jcm9020377 (registering DOI) - 30 Jan 2020
Abstract
Background: Saliva, the most readily available body fluid, is the product of genes which are in constant activity throughout life. Measurement of saliva can predict the onset of some diseases years before their accumulation in vulnerable tissues causes clinical signs to appear. The [...] Read more.
Background: Saliva, the most readily available body fluid, is the product of genes which are in constant activity throughout life. Measurement of saliva can predict the onset of some diseases years before their accumulation in vulnerable tissues causes clinical signs to appear. The purpose of this study was is to demonstrate current applications of saliva analysis and to predict and prevent disease progression. Methods: We measured levels of Abeta42, C-reactive proteins (CRPs), and tumornecrosis factors (TNFs) in saliva from both healthy and fatal diseased cases such as cancer, Alzheimer’s disease (AD), and coronary heart disease by ELISA-mediated techniques. We also immunostained human tissue sections with antibodies specific to these proteins to demonstrate the data are comparable. Results: We found all the proteins expressed constantly in saliva from healthy controls but increased in diseased cases. This was accompanied by data from immunohistochemistry. It was also found that these proteins wereexpressed in high amounts in some healthy controls, which reflects high risk for the onset of diseases such as AD and heart diseases.Conclusions: It is concluded that measuring changes in essential gene products in saliva can predict onset of fatal diseases and open the door to effective protection measures, thus preventing premature death. Full article

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