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The chloride content is a critical factor influencing the corrosion of steel fibers in concrete. This study focused on the corrosion behaviors of steel fibers exposed to simulated concrete pore solutions with different chloride contents. The corrosion rates of the steel fibers were calculated based on the changes in the diameter and ultimate tensile load. The electrochemical parameters for the corrosion of the steel fibers were continuously monitored for 62 days. In addition, the surface micromorphologies of the corroded steel fibers were observed using scanning electron microscopy (SEM). The results showed that based on the change in the diameter, the corrosion rate of the steel fibers increased almost linearly when the NaCl content in the simulated solution increased from 2% to 5%. However, based on the variation of the ultimate tensile load, the corrosion ratio of the steel fibers increased linearly with the increase in the exposure time when the NaCl content was less than 3%, while it increased exponentially when the NaCl content exceeded 3%. According to the open circuit potential, Tafel polarization curves, and electrochemical impedance spectroscopy (EIS), the corrosion tendency and corrosion rates of the steel fibers exposed to the simulated solutions increased significantly when the NaCl content increased from 2% to 5%. Additionally, the corrosion damage on the surfaces of the steel fibers increased notably, and after 180 days of exposure to the simulated solution with 5% NaCl, the steel fiber was almost broken. These findings will help to understand the durability of SFRC in a chloride environment. [ABSTRACT FROM AUTHOR]

As an essential nutrient, lutein (LUT) has the ability to aid in the prevention of eye diseases, cardiovascular diseases, and cancer. However, the application of LUT is largely restricted by its poor solubility and susceptibility to oxidative degradation. Thus, in this study, LUT-loaded nanogel (OVM-COS-LUT) was prepared by a self-assembly of ovomucin (OVM) and chitosan oligosaccharide (COS) to enhance the effective protection and bioavailability of LUT. The nanogel had excellent dispersion (PDI = 0.25) and an 89.96% LUT encapsulation rate. XRD crystal structure analysis confirmed that the encapsulated LUT maintained an amorphous morphology. In addition, the nanogel showed satisfactory stability with pH levels ranging from 2 to 9 and high ionic strengths (>100 mM). Even under long-term storage, the nanogel maintained an optimistic stabilization and protection capacity; its effective retention rates could reach 96.54%. In vitro, digestion simulation showed that the bioaccessibility and sustained release of OVM-COS-LUT nanogel was superior to that of free LUT. The nanogel provided significant antioxidant activity, and no significant harmful effects were detected in cytotoxicity analyses at higher concentrations. In summary, OVM-COS-LUT can be utilized as a potential safe oral and functional carrier for encapsulating LUT. [ABSTRACT FROM AUTHOR]

This study investigated the effect of alkalis on C3S hydration with and without incorporating aluminate phases. Pastes of 100% C3S and 90% C3S+10% metakaolin (MK) were prepared at 1%, 2%, and 3% Na2O content. X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to characterize the solid phase assemblages, and then the hydration degree of C3S. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to analyze the aqueous composition of pore solution. Mercury intrusion porosimetry (MIP) was used to measure the porosity of the hydrated pastes. The results highlighted the promoting effect of Na and the inhibiting effect of Al in pore solution on C3S hydration after a period of curing (90 days). Without incorporating metakaolin, the hydration degree of C3S continuously increased with the increase of Na concentration. Incorporating metakaolin into C3S can generate aluminate hydrates (carboaluminates, in this study), and the increased Na concentration can increase the dissolution or instability of carboaluminates and elevate the equilibrium Al concentration. Under this condition, the hydration degree of C3S fluctuated depending on the combined effect of Na and Al concentrations in pore solution on C3S hydration. [ABSTRACT FROM AUTHOR]

Morroniside is one of the most important iridoid glycosides from Cornus officinalis Sieb. et Zucc. In the present study, the pharmacokinetics and bioavailability studies of morroniside were conducted on Sprague-Dawley (SD) rats. A rat in situ intestinal perfusion model was used to characterize the absorption of morroniside. Caco-2 cells were used to examine the transport mechanisms of morroniside. The pharmacokinetic study of morroniside exhibited linear dose-proportional pharmacokinetic characteristics and low bioavailability (4.3 %) in SD rats. Its average Peff value for transport across the small intestinal segments changed from (3.09 ± 2.03) × 10−6 to (4.53 ± 0.94) × 10−6 cm s−1. In Caco-2 cells, the Papp values ranged from (1.61 ± 0.53) × 10−9 to (1.19 ± 0.22) × 10−7 cm s−1 for the apical to basolateral side and the Pratio values at three concentrations were all lower than 1.2. Morroniside showed poor absorption and it might not be a specific substrate of P-glycoprotein (P-gp).

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Although many studies have attempted to reconstruct millennial‐scale hurricane patterns using various proxy‐based methods, it is still unclear what the most effective proxies are to identify storm surge deposits in different environmental settings. This study quantitatively compares the application of grain‐size, loss‐on‐ignition, stable isotopes, X‐ray fluorescence, and palynological proxies in paleotempestology from an organic‐rich environment in the Florida Everglades. The nonparametric tests indicate that only 9 among the 27 parameters (mean diameter, %water, %organic, %carbonate, Ca, Sr, Ca/Ti, Cl/Br, and marine microfossils) exhibited significant differences between storm‐surge and in situ deposits. The principal component analysis shows that five marine indicators (Sr, Ca, Ca/Ti, %Carbonate, and Marine microfossils) have the closest association with the allochthonous samples, while Cl/Br and Mz are the most sensitive proxies in low‐ and high‐energy environments, respectively. Moreover, organic geochemical proxies (e.g., δ13C and δ15N of bulk sedimentary organic matter) are ineffective for identifying storm‐surge deposits in organic‐rich mangrove environments. Plain Language Summary: To help objectively identify the occurrence of storm‐surge deposits in coastal sediment cores, this study uses a statistical approach to evaluate the effectiveness of 27 widely used sedimentological, organic and inorganic geochemical, and biological parameters in distinguishing allochthonous deposits from autochthonous deposits in an organic‐rich environment in the Florida Everglades. The results show that Ca, Sr, Ca/Ti, and marine microfossil are four of the most sensitive parameters to distinguish storm‐surge deposits in organic‐rich environments in south Florida. In addition, Cl/Br can be used to indicate storm surge inundation in further inland and lower‐energy environments. Moreover, organic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones. Future studies need to explore the use of more specific organic geochemical proxies (e.g., biomarker) in mangrove‐dominated environments and evaluate the effective proxies in detecting storm deposits from sandy, deltaic/estuarine, and nontropical coastal environments. Key Points: Ca, Sr, Ca/Ti, and marine microfossil are the most sensitive parameters to identify storm‐surge deposits in organic‐rich environmentsCl/Br can be used to indicate storm surge inundation in further inland and lower energy environmentsOrganic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones [ABSTRACT FROM AUTHOR]

The corrosion of steel fibers is a direct cause of the deterioration of steel fiber-reinforced concrete in chloride environments. This study mainly investigated the corrosion behavior of steel fibers exposed to NaCl solutions with pH=7 , 10, 11, 12, and 13. The corrosion rate of the steel fibers was calculated according to the change of the diameter and ultimate tensile load. The electrochemical parameters of the steel fibers corrosion were continuously monitored. The morphology of the steel fibers affected by chloride attack was observed by scanning electron microscope (SEM). The results reveal that the corrosion rate of the steel fibers decreased as the pH of the NaCl solution increased from 7 to 13, and it was very small at pH≥12. According to the open circuit potential, corrosion potential, corrosion current density, and electrochemical impedance spectroscopy, the steel fibers exhibited a high corrosion tendency and corrosion rate when exposed to NaCl solutions with pH≤12. However, they exhibited low corrosion tendency in the chloride solution with pH=13. The surface roughness of the steel fibers exhibited only a slight increase after exposure to the NaCl solution with pH=13 for 180 days. [ABSTRACT FROM AUTHOR]

The Asian interior has the largest mid-latitude arid zone in the Northern Hemisphere, and so has become increasingly attractive for studying the initiation and the past extent of aridification in this zone. Given the enormousness of the Asian interior, it remains unclear how old and extensive the eolian deposits might have been, and what wind regimes have been responsible for the formation of the mid-latitude arid zone. Here we report new eolian records of widespread Tertiary eolian deposits in a region far from the Chinese Loess Plateau, the giant Junggar inland basin of northwestern China. Our results demonstrate that the earliest eolian deposition initiated ca. 24 Ma. We interpret that the Tertiary eolian dust in the Junggar Basin was transported by westerly winds, possibly from areas in Kazakhstan; the dust differs from the airborne dust transported by winter monsoon winds from the deserts of Mongolia and northern China that accumulated on the Loess Plateau. These results further reveal that the climate pattern, similar to that of the present, has prevailed at least since the latest Oligocene in Central Asia. doi: 10.1130/G30776.1

The Tianshan Range is one of the longest and highest mountain belts in Central Asia, stretching east-west for ~2500 km. Uplift of this late Paleozoic orogenic belt resulted from intracontinentai deformation caused by the collision of the Indian and Eurasian plates during the Cenozoic era. To constrain the timing of Cenozoic tectonic deformation of the Tianshan Range, we analyzed the magnetostratigraphy of 3780-m-thick Neogene deposits from the Kuqa foreland basin of southern Tianshan. The geometry measurements and magnetic fabric data show that syntectonic growth strata began to accumulate at ~6.5 Ma ago, indicating that crustal shortening initiated in the latest Miocene. The increase in sedimentation rate and an abrupt change of the magnetic fabric parameters also occurred at 6.5 Ma, accompanied by onset of syntectonic growth strata. The latest Miocene crustal shortening is a significant tectonic event in the foreland basin of the southern Tianshan Range in response to the India-Eurasia collision. doi: 10.1130/G30278A.1

The Taklimakan Desert is the world's second-largest shifting sand desert, located in the rain shadow of the Tibetan Plateau. The initiation of desert formation in the Asian interior is one of the most prominent climate changes in the Northern Hemisphere during the Cenozoic Era. Dating the earliest formation of this desert is important for understanding the climatic effects of the uplifted Tibetan Plateau. Here we report 1071-m-thick Neogene deposits with intercalated eolian dune sands from the only outcrop in the central Taklimakan Desert. Based on paleomagnetic measurements, biostratigraphic age control, and previous electron spin resonance dating results, the oldest in situ eolian dune sands were confirmed to be ca. 7 Ma, much older than the previous reported wind-blown siltstone from the southern edge of the Taklimakan Desert. This new result indicates that desert conditions initiated ca. 7 Ma in the center of the Tarim Basin. We attribute this event to the late Cenozoic climatic deterioration and/or to the rain-shadow effect caused by late Miocene uplift of the northern Tibetan margin.

Licorice is known as "Gan-Cao" in traditional Chinese Medicine (TCM), belonging to the genus Glycyrrhiza (Family: Fabaceae/Leguminosae). It has a long medicinal history and wide applications in China. Polysaccharides of licorice (LPs) are one of the key bioactive components. As herbal polysaccharides attracted increasing interest in the past several decades, their extraction, isolation, structural characterization, pharmacological activities, and medicinal application have been explored extensively. It is worth heeding that the method of extraction and purification effects LPs, apart from specie and origin specificity. This review evaluates the method of extraction and purification and demonstrates its performance in gaining specific composition and its structure-activity relationship, which might lead the readers to a fresh horizon for developing advanced treatment strategies. It is recently reported that the conformation of LPs plays a vital role as biopolymers, such as selenized modification, microencapsulation, nanocomposite, liposome formulation, drug/hydrogel combinations, biosensor device, and synergistic effect with a vaccine. In addition, LPs showed a good thermodynamics profile, as these properties enable them to interact with additional supramolecular interaction by chemical modifications or copolymerization. Functional polymers that are responsive to various external stimuli, such as physical, chemical, and biological signals, are a promising study topic. Thus, LPs are emerging as a new biomaterial that can enhance intended formulation along exerting its inherent medicinal effects. It is hoped that this review will provide a basis for the utilization and further developments of licorice polysaccharides in the vast medium. [ABSTRACT FROM AUTHOR]

Depressive disorders are a severe psychiatric and social problem that affect more than 4% of the global population. Depressive disorders have explicit hereditary characteristics; however, the precise driving genetic force behind these disorders has not yet been clearly illustrated. In the present study, we recruited a three-generation Chinese pedigree in which 5 of 17 members had long-term depression. We conducted whole-exome sequencing to identify the genetic mutation profiles of the family, and a list of susceptible genetic variations that were highly associated with depression onset was revealed via multiple omics analysis. In particular, a non-synonymous single nucleotide variation in the oxoglutarate dehydrogenase-like (OGDHL) gene, rs2293239 (p.Asn725Ser), was identified as one of the major driving genetic forces for depression onset in the family. This variant causes an important conformational change in the transketolase domain of OGDHL , thus reducing its binding affinity with the cofactor thiamine pyrophosphate and eventually resulting in the abnormal accumulation of glutamate in the brain. Brain imaging analysis further linked the rs2293239 variant with an enlarged amygdala and cerebellum in depressive family members. In summary, the present study enhances the current genetic understanding of depressive disorders. It also provides new options for prioritizing better clinical therapeutic regimens, as well as identifying a new protein target for the design of highly specific drugs to treat depressive disorders. [ABSTRACT FROM AUTHOR]

Background. Ferroptosis is a type of cell death with major topic of debate under current research and plays an important role in disease regulation. Objective. In this study, the literature management software Bibexcel and knowledge graph tool VOSviewer were used to summarize and analyze the international research trends and hotspots about ferroptosis in recent years, which highlight the disease mechanism, diagnosis, and treatment related to ferroptosis. Material/Methods. The core collection database of Web of Science was used for retrieving ferroptosis research literature. The information such as the amount of text, the country, the period, the institution, the fund, and the keywords was extracted by the bibliometric tool Bibexcel. The cooccurrence and clustering function of VOSviewer were used to analyze the high-frequency keywords and the cooperative network of the author, institution, and country. Results. The research of ferroptosis started late and was formally proposed in 2012. It has developed rapidly and presented an "exponential" growth trend. China, the United States, Germany, Japan, and France are the main national forces of ferroptosis research development. The United States and China have a relatively high degree of support and attention to ferroptosis. Exploring oxidative stress, inducers/inhibitors, synergistic antitumor effect, relationships with other cell death types, GSH/GPX4 and iron metabolism imbalance related mechanisms of ferroptosis, and ferroptosis in the nervous system disease, ischemia-reperfusion injury, tumor, inflammation, and age-related diseases are the hot research directions. Conclusion. Ferroptosis has been a research hotspot in the field of biomedicine in recent years and has attracted the attention of scholars all over the world. The occurrence mechanism of ferroptosis and its application in neurological diseases, ischemia and reperfusion injury, tumors, inflammation, and aging are the hot directions of current research. In the future, ferroptosis can be appropriately considered for strengthening new approaches, new diseases, new inductors, new inhibitors, clinical transformation, and traditional medicine research. [ABSTRACT FROM AUTHOR]

Abstract Background The receptors for adhesion of Plasmodium falciparum-infected red blood cells (RBC) in the placenta have been identified as chondroitin-4-sulphate (C4S) proteoglycans, and the more sulphate-rich chondroitin oligosaccharides have been reported to inhibit adhesion. Since the anti-malarial drug chloroquine accumulates in lysosomes and alters normal lysosomal processes, the effects of chloroquine on the lysosomal enzyme arylsulphatase B (ASB, N-acetylgalactosamine-4-sulphatase), which removes 4-sulphate groups from chondroitin-4-sulphate, were addressed. The underlying hypothesis derived from the recognized impairment of attachment of parasite-infected erythrocytes in the placenta, when chondroitin-4-sulphation was increased. If chloroquine reduced ASB activity, leading to increased chondroitin-4-sulphation, it was hypothesized that the anti-malarial mechanism of chloroquine might derive, at least in part, from suppression of ASB. Methods Experimental methods involved cell culture of human placental, bronchial epithelial, and cerebrovascular cells, and the in vitro exposure of the cells to chloroquine at increasing concentrations and durations. Measurements of arylsulphatase B enzymatic activity, total sulphated glycosaminoglycans (sGAG), and chondroitin-4-sulphate (C4S) were performed using in vitro assays, following exposure to chloroquine and in untreated cell preparations. Fluorescent immunostaining of ASB was performed to determine the effect of chloroquine on cellular ASB content and localization. Mass spectrometry and high performance liquid chromatography were performed to document and to quantify the changes in chondroitin disaccharides following chloroquine exposure. Results In the human placental, bronchial epithelial, and cerebrovascular cells, exposure to increasing concentrations of chloroquine was associated with reduced ASB activity and with increased concentrations of sGAG, largely attributable to increased C4S. The study data demonstrated: 1) decline in ASB activity following chloroquine exposure; 2) inverse correlation between ASB activity and C4S content; 3) increased content of chondroitin-4-sulphate disaccharides following chloroquine exposure; and 4) decline in extent of chloroquine-induced ASB reduction with lower baseline ASB activity. Confocal microscopy demonstrated the presence of ASB along the cell periphery, indicating extra-lysosomal localization. Conclusions The study data indicate that the therapeutic mechanism of chloroquine action may be attributable, at least in part, to reduction of ASB activity, leading to increased chondroitin-4-sulphation in human placental, bronchial epithelial, and cerebrovascular cells. In vivo, increased chondroitin-4-sulphation may reduce the attachment of P. falciparum-infected erythrocytes to human cells. Extra-lysosomal localization of ASB and reduced impact of chloroquine when baseline ASB activity is less suggest possible mechanisms of resistance to the effects of chloroquine.

Background: At present, laboratory blood tests to support major depressive disorder (MDD) diagnosis are not available. This study aimed to screen potential mRNAs for peripheral blood biomarkers and novel pathophysiology of MDD. Methods: The present study utilized public data from two mRNA microarray datasets to analyze the hub genes changes related to MDD. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of differentially expressed genes (DEGs) were performed. Finally, some potential mRNA quality biomarkers for hub gene expression in blood were identified. Results: A total of 25 significantly co-upregulated DEGs and 98 co-downregulated DEGs were obtained from two datasets. The pathway enrichment analyses showed that co-upregulated genes were significantly enriched in the regulation of cell-matrix adhesion and mitochondrial membrane permeability which were involved in the apoptotic process. Co-downregulated genes were mainly involved in the neutrophil activation which in turn was involved in the immune response, degranulation and cell-mediated immunity, positive regulation of immune response, the Toll-like receptor signaling pathway, and the NOD-like receptor signaling pathway. From the PPI network, 14 hub genes were obtained. Among them, the subnetworks of PLCG1, BCL2A1, TLR8, FADD , and TLR4 s creened out from our study have been shown to play a role in immune and inflammation responses. Discussion: The potential molecular mechanisms that have been identified simultaneously include innate immunity, neuroinflammation, and neurotrophic factors for synapse function and development. [ABSTRACT FROM AUTHOR]

Seleno-polymannuronate (Se-PM) was prepared from alginate-derived polymannuronate (PM) through a sulfation followed by a selenylation replacement reaction. The organic selenium content of Se-PM was 437.25 μg/g and its average molecular weight was 2.36 kDa. The neuroprotection effect of Se-PM and corresponding molecular mechanisms were investigated. Our results showed that, comparing to both sulfated PM (S-PM) and PM, Se-PM remarkably inhibited the aggregation of Aβ1–42 oligomer in vitro and significantly reduced the APP and BACE1 protein expression in N2a-sw cells, highlighting the critical function of the selenium presented in Se-PM. Moreover, Se-PM decreased the expression of cytochrome c and the ratio of Bax to Bcl-2, and enhanced the mitochondrial membrane potential in N2a-sw cells. These results suggested that Se-PM treatment can markedly inhibit N2a-sw cell apoptosis and promote N2a-sw cell survival and that Se-PM might be a potential therapeutic agent for the prevention of neurodegeneration owing to its remarkable neuroprotection effect. [ABSTRACT FROM AUTHOR]

Background: Triclosan is a widely applied antimicrobial agent which affects the endocrine system and homeostasis; it may also promote the cirrhosis and hepatocellular carcinoma (HCC) growth in a mice model. The exact roles of triclosan in regulating human hepatocellular carcinoma development and treatment remain unknown. Methods: MHCC97-H, a highly aggressive HCC cell line, was treated with indicated concentration of triclosan or sorafenib. The expression of drug-resistance genes was examined by qPCR. The clearance or metabolism of sorafenib was determined by liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS). MTT assay was used to examine the MHCC97-H cell proliferation. Nude mice were used to exam the anti-tumor effect of sorafenib on subcutaneous and intrahepatic growth of MHCC97-H cells. Results: In the present study, triclosan could induce the expression of drug-resistance genes in MHCC97-H cells (a highly aggressive HCC cell line), accelerate the clearance of sorafenib, and attenuate the anti-proliferation effect of this molecular targeted agent in MHCC97-H cells. Triclosan decreased the antitumor effect of sorafenib on subcutaneous and intrahepatic growth of MHCC97-H in nude mice. Conclusion: By discovering the fact that triclosan treatment enhances sorafenib resistance in HCC cells, this work suggests exposure of triclosan is detrimental to HCC patients during chemotherapy. [ABSTRACT FROM AUTHOR]

Peatlands in the Sanjiang Plain could be more vulnerable to global warming because they are located at the southernmost boundary of northern peatlands. Unlike bacteria, fungi are often overlooked, even though they play important roles in substance circulation in the peatland ecosystems. Accordingly, it is imperative that we deepen our understanding of fungal community structure and diversity in the peatlands. In this study, high-throughput Illumina sequencing was used to study the fungal communities in three fens in the Sanjiang Plain, located at the southern edge of northern peatlands. Peat soil was collected from the three fens which developed during different periods. A total of 463,198 fungal ITS sequences were obtained, and these sequences were classified into at least six phyla, 21 classes, more than 60 orders and over 200 genera. The fungal community structures were distinct in the three sites and were dominated by Ascomycota and Basidiomycota. However, there were no significant differences between these three fens in any α-diversity index (p > 0.05). Soil age and the carbon (C) accumulation rate, as well as total carbon (TC), total nitrogen (TN), C/N ratio, and bulk density were found to be closely related to the abundance of several dominant fungal taxa. We captured a rich fungal community and confirmed that the dominant taxa were those which were frequently detected in other northern peatlands. Soil age and the C accumulation rate were found to play important roles in shaping the fungal community structure. [ABSTRACT FROM AUTHOR]

Understanding the response of wetlands to climate changes could provide useful insights toward predicting the wetlands future in a warmer world. Here, we present a well-dated peat/mud profile with multiple proxies to reconstruct the historic development of Honghe wetland and discuss its response to the East Asian monsoon variations during the Holocene. The results show that the Honghe wetland developed as a shallow-water lake in the mid-early Holocene during a time of high precipitation from the East Asian monsoon. At 4600 years BP, peat layers appeared with sharp increases in the accumulation rate, grain-size Md and arboreal plants, marking a decline in water levels with the relative dry climate. Moreover, the transition corresponds well to the mid-Holocne monsoon weakening event and we suggest the decrease of the monsoon associated precipitation plays a critical role in driving the lake-peatland transition in Honghe. Facing the intensified summer monsoon in future, we suggest some practical measures should be taken to protect the present wetlands from changing back to lakes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bacterial variation within microhabitats associated with the black stone of the Black Gobi desert were investigated. • Bacterial communities within microhabitats were highly different in the desert ecosystems. • Microhabitats formed by black stones support highly diverse and biologically active bacterial communities. • Major environmental controls were water content, total carbon, and total nitrogen. Desert soil around the black stones is highly complex, which substantially affects the diversity and composition of inhabiting microbes. The existence of black stones in the southern part of the Black Gobi desert of China could provide microhabitats for diverse bacterial communities that remain unexplored. Hence, Illumina MiSeq sequencing was used to determine the differences in bacterial communities associated within microhabitats in three sites of the Black Gobi desert, China. Our results show that bacterial communities are significantly affected by each microhabitat. For instance, the α -diversity of bacterial communities indicated more remarkable diversity and richness in these microhabitats. Considering β -diversity, variances were reported mainly in the Proteobacteria (30%), Actinobacteria (26%), Chloroflexi (19%), and Firmicutes (9%). Firmicutes were markedly enriched in the upper surface, especially in site 1. Compared to other microhabitats, the relative abundance of Proteobacteria was greater in the subsurface, and they were also more dominant in the other two sites. Network analysis of soil factors and bacterial genera showed that the most significant-occurrences were positively correlated, demonstrating potential synergistic interactions. Collective with the predicted function profiles and the redundancy analysis, these results indicated the highest variances in bacterial community structure and function in Black Gobi Desert ecosystems. These differences are likely closely related to the soil parameters, mainly water content, total carbon, and total nitrogen, and might be associated with black stones. This study concludes that microhabitats formed by black stones support highly diverse and biologically active bacterial communities. These microhabitats with extreme environmental conditions deliver new opportunities to explore soil bacterial communities at relevant spatial scales in the Black Gobi desert. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the metabolic stability and cleavage sites of exendin-4 in rat tissue homogenates, as well as to identify the types of proteases involved in exendin-4 degradation. The stability of exendin-4 in kidney and liver homogenates from rats was evaluated using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) with gradient elution. Furthermore, we used a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and LC-ESI-MS/MS to identify the structures of the major degradation products of exendin-4, and peptidase inhibitors were used to characterize exendin-4 degradation in rat liver and kidney homogenates and to identify the proteases involved in exendin-4 metabolism. Exendin-4 had a half-life of 7.8 and 100.9 min in the kidney and liver homogenate, respectively. The enzymes most likely to be involved in the degradation of exendin-4 were aminopeptidases, serineproteases, and metalloproteases. Exendin-4(15-39) and exendin-4(16-39) were the predominant direct exendin-4 metabolites in the kidney, and the main product of exendin-4 metabolism in the liver was exendin-4(12-39). Our results indicated that the metabolism of exendin-4 involved an initial endoproteolytic cleavage and subsequent exoproteolytic digestion. The degradation of exendin-4 in the kidney and liver homogenates followed distinct patterns, and the primary cleavage sites of exendin-4 degradation in rat kidney homogenates were located after AA-14, and -15, whereas those in rat liver homogenates were located after AA-11. [ABSTRACT FROM AUTHOR]

Recently, certain lots of heparin have been associated with an acute, rapid onset of serious side effects indicative of an allergic-type reaction. To identify potential causes for this sudden rise in side effects, we examined lots of heparin that correlated with adverse events using orthogonal high-resolution analytical techniques. Through detailed structural analysis, the contaminant was found to contain a disaccharide repeat unit of glucuronic acid linked β1→3 to a β-N-acetylgalactosamine. The disaccharide unit has an unusual sulfation pattern and is sulfated at the 2-O and 3-O positions of the glucuronic acid as well as at the 4-O and 6-O positions of the galactosamine. Given the nature of this contaminant, traditional screening tests cannot differentiate between affected and unaffected lots. Our analysis suggests effective screening methods that can be used to determine whether or not heparin lots contain the contaminant reported here. [ABSTRACT FROM AUTHOR]

This work aims to investigate the effect of additional flue gas desulfurization gypsum (FGDG) on the properties of calcium sulfoaluminate cement (CSAC) blended with ground granulated blast furnace slag (GGBFS). The hydration rate, setting time, mechanical strength, pore structure and hydration products of the CSAC-GGBFS mixture containing FGDG were investigated systematically. The results show that the addition of FGDG promotes the hydration of the CSAC-GGBFS mixture and improves its mechanical strength; however, the FGDG content should not exceed 6%. [ABSTRACT FROM AUTHOR]