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Affordable and therapeutically effective biomaterials are required for successful treatment of orthopaedic critical-size bone defects. Calcium phosphate (CaP) ceramics are widely used for bone repair and regeneration, however, further optimization of their properties and biological performance is still required. To improve the existing CaP bone graft substitutes, novel synthesis and production approaches are needed that provide a fine control over the chemical and physical properties and versatility in the delivery format. In this study, a microfluidic strategy for production of CaP microparticles with different sizes derived from highly monodisperse droplets is proposed for the controlled synthesis of bioactive CaP ceramics. Microfluidic droplets, that served as microreactors for CaP precipitation, allowed the production of different CaP phases, as well as strontium-substituted CaP. By varying the concentration of the precursor solution, microparticles with different porosity were obtained. The droplet microfluidic system allowed direct visualization and quantification of the reaction kinetics. Upon production and purification of the microparticles, the biocompatibility and bioactivity were tested in vitro using human mesenchymal stromal cells (hMSCs). Cell attachment was analysed by imaging of the cytoskeleton and focal adhesions Moreover, cell proliferation, metabolic activity, alkaline phosphatase activity and mRNA expression of a set of osteogenic markers were quantified. We demonstrated that droplet microfluidics is a functional technique for the synthesis of a range of bioactive CaP-based ceramics with controlled properties. Calcium phosphate (CaP) ceramics are widely applied synthetic biomaterials for repair and regeneration of damaged bone; yet, CaP bone graft substitutes require further improvement to fully replace natural bone grafts in challenging clinical situations. To this end, novel synthesis and production approaches are needed that provide a fine control over the chemical and physical properties. Here, we developed a microfluidic platform for production of CaP microparticles with different size, composition and porosity, derived from monodisperse droplets. We demonstrated that CaP microparticles produced using this platform supported growth and differentiation of human mesenchymal stromal cells. This platform is a useful tool for developing a variety of CaPs in a controlled manner to study their physicochemical properties in relation to their bioactivity. [Display omitted] [ABSTRACT FROM AUTHOR]

The Early Miocene sites of Napak (Uganda), which have been prospected by the Uganda Palaeontology Expedition since 1985, have yielded abundant fossil remains, including a rich and diverse rodent fauna. Ever since the work of Lavocat (1973) on the East African Miocene rodents, which focused mainly on the Kenyan remains (but included some material from Napak discovered by Bishop during the 1950s and 1960s), few studies have been made on the Ugandan specimens. This lack provides motivation for further study of Napak micro-mammals, especially the abundant rodents, which were collected at five sites, Napak IV, V, XV, XXX and XXXI. The fossils described here are attributed to six species representing four families: Afrocricetodontidae (Afrocricetodon songhori , Protarsomys macinnesi), Myophiomyidae (Myophiomys arambourgi), Kenyamyidae (Simonimys genovefae , Kenyamys mariae) and Sciuridae (Vulcanisciurus africanus). Comparison of the dentition of extant and extinct taxa allows us to propose dietary hypotheses (granivory, herbivory and omnivory) for these rodents. In addition, the fossil rodents associated with other fauna from the same localities suggest a more-or-less dense forest environment with clearings, and the probable presence of a humid climate at the time of deposition. [ABSTRACT FROM AUTHOR]

Abstract: Vitamin C has been associated with a reduced risk of chronic diseases, but the biological pathways regulated by vitamin C are not all known. The objective was to use a proteomics approach to identify plasma proteins associated with circulating levels of ascorbic acid. Men and women (n=1022) 20–29 years of age from the Toronto Nutrigenomics and Health Study completed a general health and lifestyle questionnaire and a 196-item food frequency questionnaire and provided a fasting blood sample. Circulating ascorbic acid was analyzed by high-performance liquid chromatography, and a mass-spectrometry-based multiple reaction monitoring method was used to measure 54 proteins abundant in plasma that are involved in numerous physiologic pathways. Mean protein concentrations were compared across tertiles of serum ascorbic acid using analysis of covariance adjusted for sex, ethnocultural group, season of blood draw, hormonal contraceptive use among women, waist circumference and tertiles of plasma α-tocopherol. A Bonferroni significance level of P<.0009 was applied, and analyses were adjusted for multiple comparisons using the Tukey–Kramer procedure. Levels of complement C9, ceruloplasmin, alpha-1-anti-trypsin, angiotensinogen, complement C3, vitamin D binding protein and plasminogen were inversely associated with levels of ascorbic acid. The inverse association between ascorbic acid and vitamin D binding protein was highest in those with higher levels of serum 25-hydroxyvitamin D. In conclusion, several plasma proteins from various physiologic pathways are significantly associated with circulating levels of ascorbic acid. These findings suggest that vitamin C may have novel physiological effects. [Copyright &y& Elsevier]

Abstract: Amazon flint kaolin, considered useless from an economic and industrial point of view, was calcined at 850 and 950°C to obtain metakaolin samples. These samples were subsequently treated with sulfuric acid (4M) by assisted heating with microwave radiation. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy and N2 physisorption; the surface acidity was determined by titration with 0.2M KOH. The materials obtained were used as catalysts in the esterification of oleic acid with methanol. Metakaolin that was calcined at 850°C and activated at 400W for 15min presented a surface area of 187m2 g−1, yielding acidic sites with a concentration of 4.32mmolg−1 and a conversion of 96.5% (115°C, 40min, molar ratio of oleic acid: methanol 1:60). In addition to a lower preparation time, the flint metakaolin activated by microwave radiation gave a catalytic performance equivalent or superior to the one prepared by reflux, as well as it showed considerably reduced reaction time and temperature. [Copyright &y& Elsevier]

Abstract: Vitamin E is a lipophilic antioxidant that has been inversely associated with certain chronic diseases; however, the biological processes regulated by this vitamin have not been fully elucidated. The objective of the present study was to examine the association between the most biologically active and abundant form of vitamin E in the circulation, α-tocopherol, and the plasma proteome. Subjects were from the Toronto Nutrigenomics and Health Study and included men and women (n=1,022) who completed a general health and lifestyle questionnaire and 196-item food frequency questionnaire, and provided a fasting blood sample. Plasma α-tocopherol concentrations were measured by high-performance liquid chromatography and 54 plasma proteins were assayed by a mass spectrometry-based multiple reaction monitoring method. Analysis of covariance was used to compare mean concentrations of plasma proteins across tertiles of α-tocopherol. Plasma concentrations of apolipoprotein C-III, fibrinogen alpha, beta, and gamma chains, fibronectin and fibrinopeptide A were significantly and positively associated with plasma α-tocopherol, while intermediate levels of α-tocopherol were significantly associated with higher levels of alpha-1B-glycoprotein (all P<.0009). These findings show that circulating levels of α-tocopherol are significantly associated with specific plasma proteins and suggest novel physiological effects of vitamin E. [Copyright &y& Elsevier]

Background: Recent genome-wide association studies (GWASs) from populations of European descent identified single nucleotide polymorphisms (SNPs) in aryl-hydrocarbon receptor (AHR) and cytochrome P450 1A1 and 1A2 (CYP1A1-CYP1A2) genes that are associated with habitual caffeine and coffee consumption. Objective: We examined whether these SNPs (AHR: rs6968865 and rs4410790; CYP1A1-CYPIA2: rs2472297 and rs2470893) and 6 additional tag SNPs in the AHR gene were associated with habitual caffeine consumption in a Costa Rican population. Design: Subjects were from a case-control study of gene-diet interactions and myocardial infarction. Subjects with hypertension or missing information on smoking, caffeine intake, or genotype were excluded. Subjects were genotyped by using polymerase chain reaction with mass spectrometry-based detection, and caffeine intake was assessed by using a validated food-frequency questionnaire. Results: Compared with subjects who consumed <100 mg caf- feine/d, subjects who consumed >400 mg caffeine/d were more likely to be carriers of the T, C, or T allele for rs6968865, rs4410790, and rs2472297, respectively. The corresponding ORs and 95% CIs were 1.41 (1.03, 1.93), 1.41 (1.04, 1.92), and 1.55 (1.01, 2.36). Multivariate-adjusted ORs (95% CIs) for rs6968865 were 1.44 (1.03, 2.00) for all subjects, 1.75 (1.16, 2.65) for non- smokers, 1.15 (0.58, 2.30) for current smokers, 2.42 (1.45, 4.04) for subjects >57 y old, and 1.00 (0.65, 1.56) for subjects <57 y old. A similar effect modification was observed for rs4410790 but not for rs2472297. Conclusion: Our findings show that previous associations between SNPs in AHR and CYP1A1-CYPIA2 and caffeine and coffee consumption from GWASs in European populations are also observed in an ethnically distinct Costa Rican population, but age and smoking are important effect modifiers. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the presence of premature subclinical atherosclerosis, measured by examining carotid intima-media thickness (IMT) and to investigate whether the IMT may be linked to low-grade chronic inflammation, assessed by C-reactive protein (CRP), in young women with polycystic ovary syndrome (PCOS). Methods: Fifty seven PCOS patients and 37 similarly aged and weight controls underwent B-mode ultrasonography of the carotid arteries for IMT measure. All these women were also screened for CRP and metabolic parameters including fasting insulin, glucose, lipid and androgen levels. Differences between means were analyzed by Student''s unpaired t-test and analysis of correlations between parameters was performed by using Pearson''s correlation. Results: CRP was significantly higher in PCOS patients than in controls (3.1mg/dL vs. 1.4mg/dL; p =0.004). No difference was noted in IMT mean between PCOS cases and controls (0.52mm vs. 0.53mm; p =0.35). IMT did not correlate with CRP but exhibited a significant positive correlation with total testosterone (r =0.72, p =0.01). Conclusion: This study suggests that PCOS itself is not associated with structural arterial injury, carotid IMT is not linked to low-grade chronic inflammation and hyperandrogenism may be associated with subclinical atherosclerosis and cardiovascular risk in young women with PCOS. Additional research is needed to clarify these findings. [Copyright &y& Elsevier]

Defensins comprise a polyphyletic group of multifunctional defense peptides. Cis-defensins, also known as cysteine stabilized αβ (CSαβ) defensins, are one of the most ancient defense peptide families. In plants, these peptides have been divided into two classes, according to their precursor organization. Class I defensins are composed of the signal peptide and the mature sequence, while class II defensins have an additional C-terminal prodomain, which is proteolytically cleaved. Class II defensins have been described in Solanaceae and Poaceae species, indicating this class could be spread among all flowering plants. Here, a search by regular expression (RegEx) was applied to the Arabidopsis thaliana proteome, a model plant with more than 300 predicted defensin genes. Two sequences were identified, A7REG2 and A7REG4, which have a typical plant defensin structure and an additional C-terminal prodomain. TraVA database indicated they are expressed in flower, ovules and seeds, and being duplicated genes, this indicates they could be a result of a subfunctionalization process. The presence of class II defensin sequences in Brassicaceae and Solanaceae and evolutionary distance between them suggest class II defensins may be present in other eudicots. Discovery of class II defensins in other plants could shed some light on flower, ovules and seed physiology, as this class is expressed in these locations. Image 1 • Two class II defensins were identified. • A7REG2 and A7REG4 could be derived from gene duplication events. • These sequences do not have the classical γ-core sequence "GXC". • Class II defensins may be widespread in eudicots. • Class II defensins genes are expressed in flowers, ovules and seeds. [ABSTRACT FROM AUTHOR]

Onion skin is biomass commonly discarded in the environment, rich in bioactive compounds with antioxidant and antimicrobial potential; thus, we propose valorizing this residue using cryogels as carriers. This study aimed to produce bioactive cryogels based on corn starch and red onion skin extract (ROSE). Cryogels were prepared by starch gelatinization, with five freeze/thaw cycles, adding 5, 10, and 15% (w/w) of ROSE. The ROSE presented total phenols, flavonoids, and volatile organic compounds (VOCs), with esters being the majority. These compounds are responsible for the biological activity of ROSE. The cryogels displayed homogeneous morphology and randomly oriented pores. The water absorption capacity of the cryogels reached 658.3%. The cryogels showed low density reaching 0.153 g/cm3; high porosity of up to 83.76%; thickness of up to 0.83 cm; and low moisture of up to 3.4%. The texture profile showed that the incorporation of ROSE increased hardness. The ROSE incorporated in the cryogel had higher thermal stability when compared to its free form, increasing degradation temperature of about 155.28 °C. The cryogels with ROSE presented high antioxidant activity against ABTS and DPPH radicals ranging from 45.4 to 90.5%. In addition, they showed antibacterial action, with total inhibition of the proliferation of pathogenic bacteria Salmonella Typhimurium and Listeria monocytogenes. The cryogel, without ROSE presented greater in vitro degradability due to the breaking of the glycosidic bonds. The cryogels are efficient matrices with the potential for application as water absorbents in fresh food products that release exudates and carriers of antioxidant and antimicrobial compounds. [Display omitted] • The skin of red onion presents a high amount of bioactive and volatile compounds. • Cryogels can be produced based on corn starch and red onion skin extract (ROSE). • Bioactive cryogels are water superabsorbent with porous structures and low density. • Starch cryogels with ROSE exhibit antioxidant and antimicrobial activities, and thermal stability. • ROSE hinders the enzymatic degradability of corn starch-based cryogels. [ABSTRACT FROM AUTHOR]

• C. pseudotuberculosis infection can affect the production of sexual hormones. • Current studies have evaluated this influence in experimentally challenged animals. • Naturally infected does had greater levels of progesterone 20 days after mating. • Serum progesterone concentration were correlated with specific antibodies levels. • Five infected and 1 not-infected female goats miscarried during the observation time. Caseous Lymphadenitis (CLA) is an infectious disease that affects small ruminants, and the bacterium Corynebacterium pseudotuberculosis is its etiologic agent. This disease presents a high morbidity and a great economic impact on goat farming, leading to reduced milk and meat production and reproductive losses. The available data about the influence of C. pseudotuberculosis on the reproductive system were obtained after experimental inoculations. In this way, this study aimed to evaluate the influence of the natural infection by C. pseudotuberculosis on the luteal function and serum progesterone (P 4) levels in goats. Sixteen female goats were diagnosed for the presence of C. pseudotuberculosis specific antibodies and divided into 2 groups: CLA positive and negative animals. They were submitted to estrous synchronization, followed by controlled mating. Corpus luteum and serum levels of P 4 were evaluated on the 7th and 20th days after mating (D7 and D20). The ultrasonographic results were not statistically different between the 2 groups, as well as serum P 4 levels on D7. However, a significant increase in serum P 4 levels on the CLA positive group was identified on D20, along with a significant correlation between C. pseudotuberculosis specific antibody production, and P 4 serum levels. The result of this study indicates that the infection by C. pseudotuberculosis may influence the reproductive status of female goats through an enhanced production of progesterone. [ABSTRACT FROM AUTHOR]