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Every year, new organisms that survive and colonize adverse environments are discovered and isolated. Those organisms, called extremophiles, are distributed throughout the world, both in aquatic and terrestrial environments, such as sulfurous marsh waters, hydrothermal springs, deep waters, volcanos, terrestrial hot springs, marine saltern, salt lakes, among others. According to the ecosystem inhabiting, extremophiles are categorized as thermophiles, psychrophiles, halophiles, acidophiles, alkalophilic, piezophiles, saccharophiles, metallophiles and polyextremophiles. They have developed chemical adaptation strategies that allow them to maintain their cellular integrity, altering physiology or improving repair capabilities; one of them is the biosynthesis of extracellular polysaccharides (EPS), which constitute a slime and hydrated matrix that keep the cells embedded, protecting from environmental stress (desiccation, salinity, temperature, radiation). EPS have gained interest; they are explored by their unique properties such as structural complexity, biodegradability, biological activities, and biocompatibility. Here, we present a review concerning the biosynthesis, characterization, and potential EPS applications produced by extremophile microorganisms, namely, thermophiles, halophiles, and psychrophiles. A bibliometric analysis was conducted, considering research articles published within the last two decades. Besides, an overview of the culture conditions used for extremophiles, the main properties and multiple potential applications of their EPS is also presented. • Extremophiles have developed adaptation strategies to maintain their cellular integrity. • Biosynthesis of extracellular polysaccharides (EPS) is one of their strategies. • EPS' structural diversity makes them competitive with current commercial polysaccharides. • EPS from extremophiles can be considered as new promising "green gold" in biotechnology. [ABSTRACT FROM AUTHOR]

• First report on the production and characterization of exopolysaccharide produced by Haloferax mucosum. • Haloferax mucosum showed high exopolysaccharide (EPS) production of 7.15 g/L. • EPS had a high molecular mass of 152. • EPS exhibited high emulsion stability to extreme conditions and with different nonpolar solvents. The physicochemical characterization and emulsifying functional properties of a novel exopolysaccharide (EPS) produced by haloarchaea Haloferax mucosum (DSM 27191) were investigated. This biopolymer has a high molecular weight of 152 kDa and important protein content of 10%. Different culture media compositions were investigated taking the ATCC 2185 medium as a base and supplementing with varying concentrations of yeast extract and glucose or sucrose as carbon sources to produce the EPS in a liquid medium. The highest EPS production (7.15 ± 0.44 g/L) was obtained at 96 h. EPS aqueous dispersions showed a non-Newtonian rheological behavior which was well fitted to the Cross equation. The EPS (at 0.32% w/w) was capable of stabilizing water-in-oil emulsions with different nonpolar solvents, including n -hexane, kerosene, chloroform, castor oil and mineral oil. EPS retained its emulsifying activity after to be incubated for one hour in a wide range of temperatures (25, 40, 70 and 100 °C), pH (4, 6.5, 7 and 12) and NaCl concentrations (0, 2.0 and 4.0 M). The viscoelastic behavior and stability of hexane-in-water emulsion were examined through oscillatory shear measurements. [ABSTRACT FROM AUTHOR]

Subclinical peripheral arterial disease in patients with chronic kidney disease: Prevalence and related risk factors.Background.Atherosclerotic artery disease is a common condition in patients with chronic kidney disease (CKD); however, there are few published data on the prevalence of peripheral arterial disease (PAD) in nondialyzed patients with renal insufficiency. The ankle-brachial index (ABI) is a simple, noninvasive, and reliable method to assess PAD.Methods and Results.Prevalence of PAD using ABI was investigated in 102 patients referred for the first time to a nephrology clinic with CKD in stages 3 to 5 of the K/DOQI classification, and with no previous diagnosis of PAD. Patients with ABI<0.9 were considered positive for PAD.A total of 64% of the patients were male. The mean age was 70± 11 (range 58–84) years, and the estimated creatinine clearance (CrCl) was 35± 12 (range 6–59) mL/min−1. Of the total sample, 26% were diabetics, 10% active smokers, 48% ex-smokers, and 29% had a diagnosis of coronary heart disease (CHD), 15% had been previously diagnosed of stroke, and 17% had signs and symptoms compatible with intermittent claudication, which had passed unnoticed. Thirty-two percent of patients had an ABI<0.9 (mean 0.64± 0.25). Of these patients with PAD, 84% were men (P<0.005), and only 30% presented a clinical picture compatible with intermittent claudication. Absolute risk of CHD according to the Framingham 1998 score was higher in the PAD group (19.3%± 6 vs. 13.1%± 8;P= 0.01). Patients with PAD were older (75± 6 vs. 66± 11 years,P= 0.000), and had worse renal function (CrCl 30.8± 12 vs. 37± 10.7 mL.min−1,P= 0.016) compared to patients without PAD, but no differences were found in cholesterol levels (total, HDL, LDL), calcium, phosphorus, or PTH. In the logistic regression analysis, independent indicators of PAD risk were male sex, age, and lower CrCl.Twelve percent of patients had an ABI≥1.3, suggestive of parietal arterial calcifications. In these patients, systolic blood pressure and pulse pressure were lower (126± 18 vs. 150± 27,P= 0.005, and 52± 13 vs. 68± 25 mm Hg,P= 0.044), i-PTH levels were higher (228± 267 vs. 117± 63 pg/mL,P= 0.01), and a larger proportion of this group was treated with calcitriol (34% vs. 13%) compared to patients with a normal ABI.Conclusion.A high prevalence of PAD, considered as an ABI<0.9, was demonstrated in nondialyzed patients with CKD. This was related with age, male sex, and higher degree of renal insufficiency, while the presence of ABI≥1.3 was associated with a greater degree of hyperparathyroidism. These data show the need to carry out routine ABI determinations in patients with CKD for early detection of peripheral arterial disease. [ABSTRACT FROM AUTHOR]

Mitochondria play an important role as an intracellular energy plant and signaling organelle. However, mitochondria also exist outside cells where they could mediate cell-to-cell communication, repair and serve as an activator of the immune response. Their effects depend on the mitochondrial state or the form in which it is present, either as a whole functional structure as fragments or only as mitochondrial DNA. Herein, we provide evidence of why extracellular mitochondria and their varying forms are considered regenerative factors or pro-inflammatory activators. Understanding these aspects will provide the base of their use in therapy or as a biomarker of disease severity and prognosis. • Extracellular mitochondria regulate cell-to-cell communication, regeneration, danger sensing and immune response. • Extracellular forms of mitochondria are freeMitos, those inside a membrane as in platelets or vesicles, and ccf-mtDNA. • Extracellular mitochondria show potential to be used as a biomarker, target for therapies, and as a therapeutic agent. [ABSTRACT FROM AUTHOR]

• Oocyte's can carry mitochondrial DNA with mutations affecting embryo health. • Mitochondrial replacement therapies (MRT) may reestablish embryo health. • MRT are invasive and could affect oocyte and embryo viability. • MitoCeption could be a non-invasive option to transfer mitochondria to oocytes. • Mitocepted mitochondria were observed in oocytes and zygotes by qPCR and fluorescence. Oocytes may carry mutations in their mitochondrial DNA (mtDNA) which affect fertility and embryo development leading to hereditary diseases or rejection. Mitochondrial replacement therapies (MRTs) such as polar body transfer, spindle transfer and pronuclear transfer, aim to change dysfunctional to normal mitochondria inside oocytes and zygotes resulting in healthier offspring. Even with promising results, MRTs techniques are invasive to oocytes and may negatively affect their viability and the success of the procedure. This article shows early evidence of the use of MitoCeption, a mitochondria transfer/transplant (AMT/T) technique to possibly induce the internalization of exogenous mitochondria in a dose-dependent manner to recipient oocytes in comparison to coincubation. By using human isolated mitochondria in a mix obtained from different donors we were able to identify their mtDNA in murine oocytes by qPCR. Fluorescence microscopy showed that exogenous and transferred mitochondria (MitoTracker ® Red) by MitoCeption were internalized in oocytes and zygotes (CellTracker® Green). After maintaining mitocepted zygotes to two-cell embryos, we transferred them to subrogate female mice and obtained healthy mice pups; however, without clear evidence of the maintenance of human mtDNA in the tissues of mice pups. These early results are puzzling, and they open the path to generate more research regarding the use of MitoCeption in comparison to coincubation in order to transfer mitochondria to oocytes using less invasive procedures. [ABSTRACT FROM AUTHOR]

This research aimed to analyze the viscoelastic behavior of mixed hydrogels based on low methoxyl citrus pectin (DE = 30.4%) and low acyl gellan, in the presence of calcium ions to assess the effect of each polysaccharide on the gelation and relaxation processes of the mixed systems. Linear viscoelastic properties were determined, and the experimental data were used to fit the generalized Maxwell model to obtain the hydrogels' relaxation times and average network mesh size. In most mixed gels, the co-gelification of gellan and pectin provided more rigid hydrogels characterized by narrow meshes (6.1–11.7 nm) and slower rearrangements of polymer chains (relaxation times (λ) between 16.7 and 55.2 s) compared to gellan gels (λ = 18.4–29.3 s). The viscoelastic behavior of the pectin-gellan gels suggests a macromolecular network organization where gellan junction zones predominate, and pectin contributes to reinforcing the mixed network. That organization generates more macromolecular interactions via calcium bridges and hydrogen bonds, promoted by the accessibility of anionic sites in both biopolymers and the low extent of branching (7 mol%) of pectin. The rheological analysis provides a new understanding concerning the hybrid pectin-gellan networks, which can be used to design new natural hydrogels for diverse applications such as biocompatible biomaterials and delivery vehicles. [Display omitted] • Co-gelification of gellan and pectin provided more rigid gels than the single ones. • The viscoelastic properties of the mixed gels are governed by gellan. • Pectin-gellan gels showed higher relaxation times than gellan due to pectin's complex structure. [ABSTRACT FROM AUTHOR]