Authigenic Iron Is a Significant Component of Oceanic Labile Particulate Iron Inventories

Particulate phases transport trace metals (TM) and thereby exert a major control on TM distribution in the ocean. Particulate TMs can be classified by their origin as lithogenic (crustal material), biogenic (cellular), or authigenic (formed in situ), but distinguishing these fractions analytically in field samples is a challenge often addressed using operational definitions and assumptions. These different phases require accurate characterization because they have distinct roles in the biogeochemical iron cycle. Particles collected from the upper 2,000 m of the northwest subtropical Atlantic Ocean over four seasonal cruises throughout 2019 were digested with a chemical leach to operationally distinguish labile particulate material from refractory lithogenics. Direct measurements of cellular iron (Fe) were used to calculate the biogenic contribution to the labile Fe fraction, and any remaining labile material was defined as authigenic. Total particulate Fe (PFe) inventories varied \u3c15% between seasons despite strong seasonality in dust inputs. Across seasons, the total PFe inventory (±1SD) was composed of 73 ± 13% lithogenic, 18 ± 7% authigenic, and 10 ± 8% biogenic Fe above the deep chlorophyll maximum (DCM), and 69 ± 8% lithogenic, 30 ± 8% authigenic, and 1.1 ± 0.5% biogenic Fe below the DCM. Data from three other ocean regions further reveal the importance of the authigenic fraction across broad productivity and Fe gradients, comprising ca. 20%-27% of total PFe

Non-Enzymatic Decomposition of Collagen Fibers by a Biglycan Antibody and a Plausible Mechanism for Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory and destructive joint disorder that affects tens of millions of people worldwide. Normal healthy joints maintain a balance between the synthesis of extracellular matrix (ECM) molecules and the proteolytic degradation of damaged ones. In the case of RA, this balance is shifted toward matrix destruction due to increased production of cleavage enzymes and the presence of (autoimmune) immunoglobulins resulting from an inflammation induced immune response. Herein we demonstrate that a polyclonal antibody against the proteoglycan biglycan (BG) causes tissue destruction that may be analogous to that of RA affected tissues. The effect of the antibody is more potent than harsh chemical and/or enzymatic treatments designed to mimic arthritis-like fibril de-polymerization. In RA cases, the immune response to inflammation causes synovial fibroblasts, monocytes and macrophages to produce cytokines and secrete matrix remodeling enzymes, whereas B cells are stimulated to produce immunoglobulins. The specific antigen that causes the RA immune response has not yet been identified, although possible candidates have been proposed, including collagen types I and II, and proteoglycans (PG's) such as biglycan. We speculate that the initiation of RA associated tissue destruction in vivo may involve a similar non-enzymatic decomposition of collagen fibrils via the immunoglobulins themselves that we observe here ex vivo

Использование гемостатического препарата Спонгостан в качестве носителя мезенхимальных стволовых клеток при лечении экспериментального недержания мочи у крыс

The adhesion and proliferation of rat adipose-derived mesenchymal stem cells (MSCs) as part of biocomposite with haemostatic drug Spongostan Absorbable Haemostatic Gelatin Powder as well as its regenerative efficiency after its introduction into the periurethral region in rats with experimental urinary incontinence were studied. It was found that MSCs rapidly adhere to the surface of the carrier and actively proliferate. The periurethral injection of biocomposite (Spongostan + MSCs) quickly and effectively recovers the urine continence function in animals that have undergone modeling of incontinence by urethrolysis. Spongostan hydrated in the ratio of 1 :24 inphosphate-saline buffer has a volume-forming effect in the urethra of experimental animals.Изучены адгезия и пролиферация мезенхимальных стволовых клеток (МСК) жировой ткани крысы в составе биокомпозита с носителем на основе гемостатического препарата Спонгостан (Spоngostan Absorbable Haemostatic Gelatin Powder), а также регенерационная эффективность биокомпозита при его введении в парауретральную область крысам с экспериментальным недержанием мочи. Установлено, что МСК быстро адгезируют на поверхности носителя и активно пролиферируют. Введение биокомпозита (Спонгостан + МСК) в парауретральную область быстро и эффективно восстанавливает функцию удержания мочи в мочевом пузыре у животных после моделирования недержания посредством уретролизиса. Спонгостан, гидратированный в соотношении 1 : 24 в фосфатно-солевом буфере, оказывает также объемообразующее действие в области уретры экспериментальных животных

Chitosan Sponges for Efficient Accumulation and Controlled Release of C-Phycocyanin

The paper proposed a new porous material for wound healing based on chitosan and C-phycocyanin (C-PC). In this work, C-PC was extracted from the cyanobacteria Arthrospira platensis biomass and purified through ammonium sulfate precipitation. The obtained C-PC with a purity index (PI) of 3.36 ± 0.24 was loaded into a chitosan sponge from aqueous solutions of various concentrations (250, 500, and 1000 mg/L). According to the FTIR study, chitosan did not form new bonds with C-PC, but acted as a carrier. The encapsulation efficiency value exceeded 90%, and the maximum loading capacity was 172.67 ± 0.47 mg/g. The release of C-PC from the polymer matrix into the saline medium was estimated, and it was found 50% of C-PC was released in the first hour and the maximum concentration was reached in 5–7 h after the sponge immersion. The PI of the released C-PC was 3.79 and 4.43 depending on the concentration of the initial solution

Carbonate Reservoir as a Source Rock

В результате комплексного детального изучения литологии, петрофизики и закономерностей распределения углеводородов-биомаркеров и углеводородов алмазоподобного строения в растворимом органическом веществе и продуктах термолиза нерастворимого органического вещества (керогена) карбонатных пород-коллекторов нижнего кембрия (осинский горизонт) Восточной Сибири был сделан вывод, что они являются одновременно и нефтематеринскими толщами. Дополнительным подтверждением такого вывода служит близкое распределение углеводородного состава на молекулярном уровне в нефтях, отобранных из тех же отложенийA complex detailed study of lithology, petrophysics, and distribution of hydrocarbon biomarkers and hydrocarbons of diamond-like structure in a soluble organic matter and products of thermolysis of insoluble organic matter (kerogen) of the Lower Cambrian Eastern Siberian сarbonate reservoir rocks (osinsky horizon) showed that these rocksare source rocksat the same time. An additional research validation of this conclusion is the close distribution of the hydrocarbon composition at the molecular level of crude oils taken from the same deposit

Candidate cell and matrix interaction domains on the collagen fibril, the predominant protein of vertebrates.

Type I collagen, the predominant protein of vertebrates, polymerizes with type III and V collagens and non-collagenous molecules into large cable-like fibrils, yet how the fibril interacts with cells and other binding partners remains poorly understood. To help reveal insights into the collagen structure-function relationship, a data base was assembled including hundreds of type I collagen ligand binding sites and mutations on a twodimensional model of the fibril. Visual examination of the distribution of functional sites, and statistical analysis of mutation distributions on the fibril suggest it is organized into two domains. The “cell interaction domain” is proposed to regulate dynamic aspects of collagen biology, including integrin-mediated cell interactions and fibril remodeling. The “matrix interaction domain” may assume a structural role, mediating collagen cross-linking, proteoglycan interactions, and tissue mineralization. Molecular modeling was used to superimpose the positions of functional sites and mutations from the two-dimensional fibril map onto a three-dimensional x-ray diffraction structure of the collagen microfibril in situ, indicating the existence of domains in the native fibril. Sequence searches revealed that major fibril domain elements are conserved in type I collagens through evolution and in the type II/XI collagen fibril predominant in cartilage. Moreover, the fibril domain model provides potential insights into the genotype-phenotype relationship for several classes of human connective tissue diseases, mechanisms of integrin clustering by fibrils, the polarity of fibril assembly, heterotypic fibril function, and connective tissue pathology in diabetes and aging

Correction of disorders in tissue perfusion, blood coagulation and fibrinolysis with Orbita apparatus on terahertz waves of cell metabolites

This article contains information on principle of operation, technical parameters and possible application of Orbita {transliteration from Russian} apparatus for hemodynamic, fibrinolytic and peripheral perfusion disorders treatment. A single exposure to terahertz waves emitted by Orbita apparatus, corresponding to frequencies of molecular absorption and emission spectra of atmospheric oxygen (129.0 GHz), completely cures coagulant and fibrinolytic disorders of animals with acute immobilization stress. A course of treatment with electromagnetic waves corresponding to frequencies of molecular absorption and emission spectra of nitrogen oxide (150.176 – 150.664) leads to normalization of disrupted peripheral tissue perfusion parameters of animal undergoing treatment and stimulates basal and induced output of nitrogen oxide. This leads to decrease in peripheral vascular resistance to microcirculation and increase in blood flow to microvasculature. Experimental data provided in this article serves as a proof of viability of Orbita apparatus for treatment of coagulant, fibrinolytic and tissue perfusion disorders