Enriched Component Research Articles

Carbonatites from the southern Brazilian Platform: A review. II: Isotopic evidences

Abstract Early and Late Cretaceous alkaline and alkaline–carbonatitic complexes from southern Brazil are located along the main tectonic lineaments of the South America Platform. Calcium-, magnesium-, and ferrocarbonatites are well represented and frequently associated even in the same complex. Primary carbonates present significant variations in C–O isotopic compositions, which are mainly due to isotope exchange with H2O–CO2-rich hydrothermal fluids, whereas fractional crystallization or liquid immiscibility probably affects the δ18O and δ13C values by no more than 2δ‰. Our isotope exchange model implies that the most significant isotopic variations took place in a hydrothermal environment, e.g., in the range 400–80°C, involving fluids with the CO2/H2O ratio ranging from 0.8 to 1. Sr–Nd–Pb isotope systematics highlight heterogeneous mixtures between HIMU and EMI mantle components, similar to the associated alkaline rocks and the flood tholeiites from southern Brazil. In spite of the strong variation shown by C–O isotopes, Sr–Nd–Pb–Os isotopic systematics could be related to an isotopically enriched source where the chemical heterogeneities reflect a depleted mantle “metasomatized” by small-volume melts and fluids rich in incompatible elements. These fluids are expected to have promoted crystallization of K-rich phases in the mantle, which produced a veined network variously enriched in LILE and LREE. The newly formed veins (enriched component) and peridotite matrix (depleted component) underwent a different isotopic evolution with time as reflected by the carbonatites. These conclusions may be extended to the whole Paraná–Etendeka system, where isotopically distinct parent magmas were generated following two main enrichment events of the subcontinental lithospheric mantle at 2.0–1.4 and 1.0–0.5 Ga, respectively, as also supported by Re–Os systematics. The mantle sources preserved the isotopic heterogeneities over a long time, suggesting a nonconvective lithospheric mantle beneath different cratons or intercratonic regions. Overall, the data indicate that the alkaline–carbonatitic magmatism originated from a locally heterogeneous subcontinental mantle.

Paleo- to Mesoproterozoic magmatic and tectonic evolution of the southwestern Yangtze Block, south China: New constraints from ca. 1.7–1.5 Ga mafic rocks in the Huili-Dongchuan area

Paleo- to early Mesoproterozoic rocks in the Yangtze Block are extremely sparse and are predominately exposed along the southwestern margin. Their petrogenesis and tectonic significance remain unclear, resulting in a limited understanding of the tectonic evolution of the southwestern Yangtze Block during this period. Therefore, we report here detailed geochronological and geochemical analyses of newly discovered Paleo- to early Mesoproterozoic mafic intrusive rocks in the Huili-Dongchuan area, southwestern Yangtze Block and interpret their petrogenesis and tectonic significance. Secondary ion mass spectroscopy (SIMS) zircon and baddeleyite U-Pb dating yielded crystallization ages of ca. 1716–1714 Ma for gabbros and diabases (referred to as the 1.72–1.71 Ga group), ca. 1705–1700 Ma for gabbros and a diabase-porphyrite (the 1.70 Ga group), and ca. 1519–1504 Ma for a gabbro and a diabase (the 1.52–1.50 Ga group), which effectively constrain the minimum depositional age of the Tong'an and Dongchuan groups that they intrude to 1.72 Ga. The three groups (or episodes) of intrusive rocks differ from each other in their chemical compositions and isotopic characteristics, most likely because of varying degrees of melting in a convective upper mantle (probably the asthenosphere), which had been metasomatized by melts with enriched components input by a plume from the lower mantle. Modeling calculations suggest that fractional crystallization (FC) and assimilation and fractional crystallization (AFC) were the most important processes involved in modifying the chemical compositions of these rocks. These magmatic activities are interpreted to have been related to mantle plumes and continental rifting that occurred in the Huili-Dongchuan area near the southwestern margin of the Yangtze Block.

Geochemistry of Cretaceous basalts from the Ontong Java Plateau: Implications for the off-axis plume–ridge interaction

Ontong Java Plateau (OJP) is the largest known igneous province preserved on Earth. The hypotheses for the origin of the OJP volcanic activities remain controversial. Here we report new major, trace-element, and Sr–Nd–Pb isotopic compositions from volcanic rocks from Ocean Drilling Program Sites 1183, 1185, 1186, and 1187 of the OJP. Samples from the OJP are tholeiitic in composition and can be divided into low- and high-Ti groups, display flat rare-earth elements (REEs) distributions that are generally similar to normal mid-ocean-ridge basalt (N-MORB) patterns with slightly positive Nb, Ta, Th, U, and Ti anomalies and negative K, Pb, and Sr anomalies. However, OJP samples have significantly enriched 87Sr/86Sr (0.703641–0.704629), 143Nd/144Nd (0.512941–0.512972), and 206Pb/204Pb (18.493–18.940) radiogenic isotopic ratios, indicating that at least three distinct FOZO-type, EM1-type, and HIMU-type enriched components are involved. Combining with the method of principal component analysis, the special geochemical compositions with depleted N-MORB-incompatible elements and enriched isotopes of OJP volcanic samples could be explained by the off-axis ridge–plume interaction model. Due to the influence of strong ridge tensile forces, the off-axis plume magmatic mantle would flow to the ridge axis and undergo decompression melting, resulting in the depletion of the highly incompatible elements but the invariability of the isotopic compositions due to the relatively long half-life of the radiogenic elements. We speculate that these isotopically enriched N-MORB-type basalts may be an exclusive product of an off-axis ridge–plume interaction.

Tracking the magmatic response to subduction initiation in the forearc mantle wedge: Insights from peridotite geochemistry of the Guleman and Kızıldağ ophiolites, Southeastern Turkey

The initiation of subduction is associated with sequential magmatic responses that lead to the formation of the forearc lithosphere, yet the detailed characteristics of these magmatic activities are not well constrained. Here we use mineral chemistries and bulk-rock trace-element contents of highly-depleted harzburgites from the Guleman and Kızıldağ ophiolites in Southeast Turkey to examine mantle wedge melting dynamics during subduction initiation. We focus on how different components from the subducting slabs potentially contribute to various stages of magmatism throughout the process. Mineral and bulk-rock compositions of these harzburgites are significantly different from those of abyssal peridotites, suggesting that our harzburgites cannot be explained as residues of anhydrous adiabatic melting and melt-rock interaction at mid-ocean ridges alone. This implies that the petrogenesis of SE Turkey harzburgites involves additional processes and components. Harzburgites with the most depleted heavy-rare earth element (HREE) contents are the ones with the highest abundance of strongly incompatible elements, which can be explained by open-system processes where the peridotites in the mantle wedge experienced melting and infiltration of enriched components simultaneously. Open-system dynamic melting models with continuous flux of sediment-derived melts can account for the observed correlation, but are numerically too low compared to the measured values. Based on the observed fractionation between Zr, Hf, and elements with similar incompatibility (middle REEs), we hypothesized the involvement of amphibolite-derived melt and modeled its numerical trace-element contents. Binary mixing between this hypothetical melt and residues of the former open-system model can coherently account for the majority of the obtained trace-element data. This indicates that magmatic events during subduction initiation likely involve multiple components and occur in multiple stages, and that melt-mantle interaction plays a significant role in oceanic forearc lithosphere formation. Based on our model, we suggest the high (Zr/MREE)N signatures in some boninites and depleted harzburgites found in modern forearcs and ophiolites could be inherited from amphibolite-derived melts. Moreover, the existence of slab melts agrees with current constraints on the reconstructed geothermal gradients during subduction initiation based on the petrology and geochemistry of metamorphic soles.

Impact of enriched environment during adolescence on adult social behavior, hippocampal synaptic density and dopamine D2 receptor expression in rats

Environmental enrichment (EE) is one experimental manipulation that induces changes in the brain. However, it is important to distinguish between physical and social components of enrichment. To this end we established four groups of rats reared in different enriched environments during the adolescent period. Our results indicate heightened social memory and increased spine density in dentate gyrus specifically in socially enriched animals. Physical enrichment increased spine density in CA1. Dopamine D2 receptor expression in hippocampus was decreased across all enrichment conditions. Altogether, our results demonstrate differing effects of physical and social enrichment, supporting an important role for environment in synaptogenesis, behavior, and dopaminergic signaling.

Large iron isotope variation in the eastern Pacific mantle as a consequence of ancient low-degree melt metasomatism

Studies of mid-ocean ridge basalts (MORB) have revealed a heterogeneous asthenospheric mantle in chemical elements and radiogenic isotopes. Here we report that MORB mantle is also heterogeneous in Fe isotopes through studying the glass samples from seamounts flanking the northern East Pacific Rise between 5° and 15°N. These samples show large Fe isotope variation with δ56Fe values (+0.03‰ to +0.36‰) exceeding the known range of MORB (+0.05‰ to +0.17‰). Such highly varied δ56Fe values cannot be well explained by seafloor alteration, fractional crystallization or partial melting processes, but instead require a source mantle significantly heterogeneous in Fe isotope compositions. Importantly, the δ56Fe values of these basalts correlate significantly with major and trace elements and Sr-Nd-Pb-Hf radiogenic isotopes, reflecting melting-induced mixing of a two-component mantle with the enriched component having heavy Fe isotope compositions dispersed as physically distinct domains in the depleted mantle matrix. The major and trace element characteristics of the enriched mantle component, as inferred from these basalts, are consistent with a low-degree melting origin. Such low-degree melts with heavy Fe isotope compositions most likely formed at sites such as the lithosphere-asthenosphere boundary beneath ocean basins, which can metasomatize the overlying oceanic lithosphere by crystallizing dikes/veins of garnet pyroxenite lithologies. Recycling of these dikes/veins with isotopically heavier Fe can readily contribute to the Fe isotope heterogeneity in the MORB mantle. However, the extremely high primitive δ56Fe values of the two alkali basalts (up to 0.34‰) require an enriched source component with unusually high δ56Fe values. We suggest that partial melts from the recycled dikes/veins of garnet pyroxenite lithologies can react with the ambient peridotitic mantle and generate a secondary garnet pyroxenite with heavier Fe isotope compositions than, but similar radiogenic isotope compositions as its precursor. Melting-induced mixing between these garnet pyroxenites (recycled and newly formed) and depleted mantle matrix can readily explain the compositional variations in elements, radiogenic isotopes and Fe isotopes observed in these seamount lavas. These new data and correlated variations offer a new dimension for understanding the origin of mantle chemical and isotopic heterogeneity in the context of chemical differentiation of the Earth.

Transcriptome Analysis of Cryphonectria parasitica Infected With Cryphonectria hypovirus 1 (CHV1) Reveals Distinct Genes Related to Fungal Metabolites, Virulence, Antiviral RNA-Silencing, and Their Regulation.

Comprehensive transcriptome analysis was conducted to elucidate the molecular basis of the interaction between chestnut blight fungus, Cryphonectria parasitica, and single-stranded RNA (ssRNA) mycovirus Cryphonectria hypovirus 1 (CHV1), using RNA-sequencing (RNA-seq). A total of 1,023 differentially expressed genes (DEGs) were affected by CHV1 infection, of which 753 DEGs were upregulated and 270 DEGs were downregulated. Significant correlations in qRT-PCR analysis of 20 randomly selected DEGs and agreement with previously characterized marker genes validated our RNA-seq analysis as representing global transcriptional profiling of virus-free and -infected isogenic strains of C. parasitica. Gene Ontology (GO) analysis of DEGs indicated that “cellular aromatic compound metabolic process” and “transport” were the two most enriched components in the “biological process.” In addition, “cytoplasm” was the most enriched term in the “cellular component” and “nucleotide binding” and “cation binding” were the two most enriched terms in the “molecular function” category. These results suggested that altered expression of genes encoding numerous intracellular proteins due to hypoviral infection resulted in changes in specific metabolic processes as well as transport processes. Kyoto Encyclopedia of Genes and Genomes function analysis demonstrated that pathways for “biosynthesis of other secondary metabolites,” “amino acid metabolism,” “carbohydrate metabolism,” and “translation” were enriched among the DEGs in C. parasitica. These results demonstrate that hypoviral infection resulted in massive but specific changes in primary and secondary metabolism, of which antiviral fungal metabolites were highly induced. The results of this study provide further insights into the mechanism of fungal gene regulation by CHV1 at the transcriptome level.

Intraoceanic back-arc magma diversity: Insights from a relic of the Proto-Tethys oceanic lithosphere in the western Qilian Orogen, NW China

The Qilian orogeny formed by subduction of the proto-Tethyan ocean along the northern margin of Gondwana. In this paper we report geochemical, zircon U-Pb-Hf, and mapping data of the Duoruonuoer volcanic rocks from the western Qilian Orogen. Based on distinct geochemical compositions, four melt types can be distinguished: boninite-like basalt, OIB-like basalt, MORB, and high-K to shoshonitic volcanic rocks (HKSV). Field relationships show a compositional change from HKSV, MORB, OIB to boninite-like basalt, from north to south. The boninite-like basalt is low to medium-K calc-alkaline, with low TiO2 (0.13–0.18 < 0.5 wt%) and high CaO/Al2O3 ratio (0.72–0.80), similar to high-Ca back-arc boninite. The geochemical characteristics of Duoruonuoer OIB-like basalt, MORB, and HKSV are similar to those of the Izu-Bonin (IB) back-arc magmatic assemblages. Boninite-like basalt is enriched in LILEs, and has low Ce/Pb, and high Sr/Nd, Ba/Nb ratios, indicating an addition of a shallow subduction-derived fluid phase. Inferred pressures of magma segregation are 0.9–1.4 GPa with temperatures of 1200–1370 °C consistent with melting of a highly depleted, low pressure hydrous mantle source. The MORB-like rock formed by mixing of depleted mantle and a subduction component, and is identical to back-arc basin floor basalt (BABB). The HKSV, dated at 475 Ma, shares the characteristics with lava from the IB back-arc seamount chains (rear-arc). Their low Ce/Pb and high Th/Yb and Th/Nb ratios are compatible with contributions from melts of deep subducting sediment and oceanic crust. High pressure (1.8–2.0 GPa) may reflect sourcing from a mantle melt at the base of thickened arc crust. The OIB-like basalts have high TiO2, Zr/Yb, Nb/Yb and Ce/Pb ratios, suggesting an enriched component from partial melting of the asthenosphere. The high-Fe8 and Ti8 composition of the Duoruonuoer OIB-like basalt is produced by fractional melting, similar to a spreading ridge segment developed a deeper source. The variety of Duoruonuoer back-arc magmatism highlights the importance of changes to the melt source region linked to replenishment of the mantle wedge by material extracted from the subducting slab and influx of more fertile mantle material. It is also controlled by evolution of the mantle wedge over time in the building of the back-arc basin. These findings provide evidence for c.475 Ma back-arc basin developed on a thickened arc lithosphere at the western Qilian Orogen.

Alkalic to tholeiitic magmatism near a mid-ocean ridge: petrogenesis of the KR1 Seamount Trail adjacent to the Australian-Antarctic Ridge

ABSTRACT Coexisting alkalic and tholeiitic basalt lavas has been identified in a seamount chain located near the Australian–Antarctic spreading ridge. The KR1 Seamount Trail (KR1 ST) is a series of volcanic seamounts extending to the southeast in the spreading direction of the Australian–Antarctic Ridge (AAR). We herein report Sr, Nd and Pb isotopic compositions and (U–Th)/He and K–Ar geochronology for dredge samples from the KR1 ST in order to evaluate mantle processes and the role of enriched components for alkalic to tholeiitic magma generation in this region. The KR1 ST is a medium-sized seamount chain that extends for ~60 km, has a maximum height of ~1600 m above the seafloor, and consists of alkaline basalts and tholeiites with formation ages of ~0.4 Ma to ≤1.3 Ma. The isotopic characteristics of the alkaline basalts (206Pb/204Pb = 19.52–19.91; 87Sr/86Sr = 0.7030–0.7033; 143Nd/144Nd = 0.5128–0.5130) from the KR1 ST reflect a dominant ‘PREMA (or FOZO)’ mantle component represented by radiogenic Pb and mildly enriched Sr and Nd isotopic compositions. On the other hand, the weak PREMA (FOZO)-affinity (206Pb/204Pb = 18.89–18.93; 87Sr/86Sr = 0.7028–0.7029; 143Nd/144Nd = ~0.5130; 3He/4He = 7.64 ± 0.13 (R/RA)) coupled with their enriched mid-ocean ridge basalt (E-MORB) characteristics of tholeiites from the KR1 ST largely overlap with the KR1 MORB composition. The potential source materials for the alkaline basalts are considered to be ancient, recycled oceanic crust (i.e. eclogite) as well as sub-KR1 depleted MORB mantle (DMM). Whereas the main source materials for the KR1 ST tholeiites are presumed to be the DMM-dominant lithology with minor recycled material. We interpret the KR1 ST as a submarine hotspot chain that was formed by asthenospheric upwelling and spreading processes that delivered fertile blobs of recycled oceanic crust to the sub-KR1 region. The fundamental reason for sub-KR1 upper mantle enrichment might be attributed to a mantle plume event that possibly occurred prior to the formation of the KR1 ST.

Effects of an Aboriginal Cultural Enrichment Program on Adolescent Mothers’ Self-Perceptions

This study explored the effects of an Aboriginal cultural enrichment initiative on the self-concept of ten pregnant or parenting adolescent women, all but one of whom were of Aboriginal descent. The cultural enrichment activities were integrated into a program of support for adolescent mothers. Questionnaires were administered to the participants at the beginning and after six weeks of participating in the cultural enrichment component of the program. The Self-Perception Profile for Adolescents (Harter, 1988) was used to measure global self-worth and self-perception across eight domains. Overall cultural identity, cultural identity achievement, cultural behaviours and sense of affirmation and belonging were measured using the 20 item Multigroup Ethnic Identity Questionnaire (Phinney, 1998b). Individual audio-taped interviews were also undertaken following completion of the post-tests. After six weeks of the cultural enrichment program, the participants’ cultural identity achievement scores increased significantly, and participants who had achieved a strong cultural identity also had higher levels of global selfworth. Average self concept became more positive in the specific domains of job competence and behavioural conduct. In the interviews, participants expressed positive reactions to the cultural component of the program, and attributed positive personal changes to the cultural experiences it provided. The results support the conclusion that it is highly beneficial to incorporate a cultural component into services for Aboriginal youth.

Petrogenesis of middle Okinawa Trough volcanic rocks: Constraints from lead isotopes in olivine-hosted melt inclusions

Olivine-hosted melt inclusions provide crucial information about their parental magma composition and evolution and represent ideal targets for determining the nature of the poorly understood and still-debated magma sources in the Okinawa Trough, a back-arc basin in the western Pacific. We present the first analyses of the lead (Pb) isotope compositions of olivine-hosted melt inclusions to evaluate the mantle properties and petrogenesis of middle Okinawa Trough volcanic rocks. The melt inclusions have more variable major and trace elements and Pb isotope compositions than the host whole-rock samples. We report the discovery of both high-207Pb/206Pb (>0.865) and low-207Pb/206Pb (<0.865) isotope compositions in melt inclusions in individual volcanic rocks, even within a single host olivine, indicating a compositionally heterogeneous magma source. The trace element and Pb isotope characteristics of the melt inclusions show that the magma source is affected by enriched components. We modeled the injection of enriched components into a magma source to explain the generation of the magma heterogeneity. The results indicate that the mixing of Pacific Ocean-type mantle (MORB), an EMI-like component from recycled lower continental crust and EMII-like material from subducted sediments can explain the low-207Pb/206Pb isotope values observed in the melt inclusions. The discovery of small proportions of melt inclusions with high 207Pb/206Pb ratios, high K2O, P2O5, Rb and U contents and low Pb and Cu contents in the studied andesites suggests that the andesitic magma may have been formed by the mixing of materials with different elemental and isotopic compositions. Our study results suggest that pervasive magma mixing may have occurred in the magma source prior to eruption in the Okinawa Trough.

Tissue‐specific roles of cardiolipin in the control of systemic energy homeostasis

The mitochondrial inner membrane is a dynamic interface that supports bioenergetic processes, intracellular communication, and transport of metabolites, lipids, and ions. The phospholipid, cardiolipin, is one of the most enriched components of this membrane and is classically ascribed an indispensable role in mitochondrial structure and function. Disruption of cardiolipin biology is causally linked to numerous pathophysiologies, including diabetes, nonalcoholic fatty liver disease, Parkinson’s disease, and Barth syndrome. Yet how cardiolipin controls metabolic function of individual mammalian tissues remains largely unknown. Therefore, we generated conditional genetic models with cardiolipin synthesis deficiency in tissues with predominantly uncoupled (i.e. brown adipose) or coupled (i.e. skeletal muscle) mitochondria. We found that tissue‐specific loss of cardiolipin had dramatically different outcomes on respiration and systemic energy homeostasis. Cardiolipin deficiency in brown adipose significantly reduced organismal insulin sensitivity and glucose tolerance, whereas loss of cardiolipin in skeletal muscle unexpectedly improved glycemic control. Moreover, in contrast to the dogmatic belief that cardiolipin is ubiquitously required, we found that certain skeletal muscle fiber types retained respiratory capacity in the face of cardiolipin depletion through mitochondrial biogenesis and fiber‐type switching. Our collective findings on tissue‐specific roles of cardiolipin reshape the fundamental understanding of mitochondrial structure and function with potential therapeutic implications for phospholipid disorders.Support or Funding InformationNovo Nordisk Foundation and the European Research Council (aCROBAT 639382)

Anti-colorectal cancer effects of scutellarin revealed by genomic and proteomic analysis

BackgroundColorectal cancer, one of the most common digestive tumors with high mortality and morbidity worldwide, currently lacks effective therapies available to improve the prognosis. This study was aimed to investigate the potency of Scutellarin against colorectal cancers, and explore the related mechanism via genomic and proteomic analysis.MethodsCell counting kit-8 assay was employed to detect the viability of HCT-116 and RKO cell lines treated with Scutellarin. The apoptosis of HCT-116 and RKO cells after Scutellarin administration was determined by TUNEL staining and Caspase 3/7 activity. Cell cycle was detected by flow cytometry analysis. The wound healing and transwell invasion test detected the role of Scutellarin in migration and invasion of HCT-116 and RKO cells. Meanwhile, the energy metabolism and growth of tumor tissues in vivo at day 28 were observed by PET-CT after Scutellarin administration with 50 mg/kg, 100 mg/kg and 300 mg/kg into 4-week-old nude mice. Blood routine and liver functions were also detected to evaluate the side effect of Scutellarin. Furthermore, the disease and function classifications which the differentially expressed genes and proteins involved after Scutellarin treatment were determined by genomic and proteomic analysis respectively.ResultsThe Scutellarin inhibited the migration and increased apoptosis of HCT-116 and RKO cell lines. Besides, Scutellarin treatment substantially decreased the growth and volume of colorectal tumors in nude mice without side effects on the blood routine and liver function. The differentially expressed genes in RKO cells after Scutellarin administration were mainly enriched in cell death and survival, organismal injury and abnormalities, and cancer. In addition, forty-seven upregulated and twenty-nine downregulated proteins were identified. Functional clustering analysis exhibited enriched biological processes, cellular components, molecular functions and related pathways of these proteins in cellular metabolic. Then protein–protein interactions analysis showed the regulatory relationship among these differentially expressed proteins.ConclusionsTaken together, the present findings revealed that Scutellarin exerted significant antitumor effect with no side effects in the blood and liver by regulating various important molecules in tumor proliferation, apoptosis and metastasis.

Bone Mineral Composition Among Long-Term Parenteral Nutrition Patients: Postmortem Assessment of Calcium, Phosphorus, Magnesium, and Select Trace Elements.

Patients receiving long-term parenteral nutrition (PN) treatment are at risk of developing metabolic bone diseases (MBDs). The bone compartment serves as a repository for a range of metal(loid)s that are administered intravenously to patients via PN solutions. Thus, the mineral composition of patient bones may be linked to the development of MBDs in this group. We measured 12 elements in bone samples obtained post mortem from 7 long-term (2-21 years) PN patients and 18 control bones obtained from hip/knee replacement surgery. The samples were cleaned, digested, and subsequently analyzed using a method based on inductively coupled plasma tandem mass spectrometry. Compared with the control group, bones obtained from PN patients were significantly (P<0.05) depleted in calcium (Ca), phosphorus (P), magnesium (Mg), chromium, and strontium and enriched in manganese (Mn), zinc, barium, cadmium (Cd), and uranium (U). No differences were observed for cobalt or lead. Depletion of major components of bone mineral (Ca, P, and Mg) and enrichment in known toxicants (Cd, Mn, U) are concerns for PN patients.

Geochronology and petrogenesis of the Late Silurian Shitoukengde mafic–ultramafic intrusion, NW China: Implications for the tectonic setting and magmatic Ni-Cu mineralization in the East Kunlun Orogenic Belt

ABSTRACT The Shitoukengde mafic–ultramafic intrusion, located in the East Kunlun Orogenic Belt, is spatially and temporally associated with the Xiarihamu Ni-Cu sulphide deposit, the second-largest Ni deposit in China. This intrusion comprises mainly lherzolite, harzburgite, olivine websterite, and gabbroic rocks. The Shitoukengde mafic–ultramafic rocks are enriched in light rare earth elements (REE) relative to heavy REE and show pronounced negative Nb–Ta anomalies. Magmatic zircon crystals of the studied samples have high δ18O values (6.5 to 8.0‰) with a weighted mean value of 7.3‰ that is higher than the typical mantle value (~5.3‰). They are characterized by high εHf(t) values (–2.0 to 9.2) and variable εNd(t) values (–4.46 to 2.83). Olivine grains from the ultramafic rocks have high forsterite (Fo) values of 79.3–86.8 and variable Ni contents of 746–3347 ppm. Our calculations indicate that parental magma of the Shitoukengde intrusion had a high-Mg basaltic composition with 10.9 wt% MgO and 9.8 wt% FeOT. Fractional crystallization and significant crustal contamination triggered S saturation and sulphide enrichment in the magma. Zircon LA-ICPMS and SIMS U–Pb analyses reveal the consistent Silurian ages of 420–424 Ma for the gabbronorite and Ol websterite, which is coeval with the Xiarihamu Ni-Cu deposit. Based on these data and the regional tectonic setting, we suggest that the Shitoukengde mafic-ultramafic rocks formed in the post-collisional, extensional environment. The cessation of subduction may have resulted in break-off of the dense subducted slab, and triggered ascent of the hot convective asthenospheric mantle. The mantle wedge was modified by the subduction-related fluids and these enriched mantle components were incorporated into the ascending asthenospheric melts at relatively shallow depths, generating the high-Mg basaltic magmas that formed the compositionally variable mafic-ultramafic rocks (e.g., Shitoukengde and Xiarihamu intrusions) in the Eastern Kunlun Orogenic belt.

Exosomes-microRNAs interacted with gastric cancer and its microenvironment: a mini literature review.

Exosomes have appeared as fundamental vehicle-modulated crosstalk among various cells in the tumor microenvironment. The systematic understanding of exosomes in gastric cancer (GC) enhances our comprehension about the tumor growth, metastasis, chemoresistance and diagnosis of cancers. The versatile functions of exosomes provide reasonable explanations about the propensity for GC metastasis. The selectively enriched components, especially some exosomal miRNAs, are potential noninvasive biomarkers for sensitive and specific GC diagnosis. Given the characteristics of exosomes, frontier researchers are stimulated to modulate the biogenesis, concentrations or release of exosomes so as to disturb malignant signals between cells. Abnormal expression profiles of exosomal miRNAs afford potential GC therapeutic or diagnostic strategies in future.

Western Northern Luzon Isotopic Evidence of Transition From Proto‐South China Sea to South China Sea Fossil Ridge Subduction

AbstractTemporal geochemical comparisons are conducted for representative magmatism from western Northern Luzon to reconstruct the Cenozoic tectonics. Oligo‐Pleistocene magmas from western Northern Luzon display elemental and Sr‐Nd‐Hf‐Pb‐O isotope geochemistry similar to intraoceanic arc magmatism, consistent with derivation from the mantle wedge, coupled with fractional crystallization. Specifically, the Oligo‐Miocene (~26.8–15.6 Ma) Central Cordillera diorite complex samples exhibit a negative correlation between Sr‐Nd isotopes, consistent with mantle metasomatism by fluids/melts released from pelagic sediments. The Mio‐Pleistocene samples (&lt;~9 Ma) exhibit consistent 87Sr/86Sr ratios with variable εNd and partially overlap with those of Scarborough seamount basalts, consistent with mantle metasomatism by fluids/melts released from the Scarborough seamount basalts, which are being subducted beneath Northern Luzon with the South China Sea fossil ridge. Temporal changes in Sr‐Nd‐Hf‐Pb isotopes are also observed for the Taiwan‐Luzon arc magmatism. The Oligo‐Miocene (&gt;~9 Ma) magmatism exhibit intraoceanic arc isotopic signatures, suggestive of a chemical imprint from subducted pelagic sediments. The Mio‐Pleistocene (&lt;~9 Ma) lavas display enriched mantle‐type isotope compositions, consistent with an input of terrigenous sediment in the mantle. The temporal variations in Sr‐Nd‐Hf‐Pb isotopes for the Taiwan‐Luzon magmatism, combined with paleomagnetic evidence, mirror a transition from the Proto‐South China Sea to the South China Sea fossil ridge subduction beneath western Northern Luzon at ~9 Ma. In addition, this study also highlights the importance of relatively enriched components in the lower plate in the maturation of overriding juvenile oceanic crust in an arc‐continent collision system.

Breed and feed affect amino acid contents of egg yolk and eggshell color in chickens

Genetic and environmental factors regulate hen egg traits. To demonstrate the possibility of producing designer eggs through genetic and environmental factors, we investigated the effects of breed and feed on egg traits using 2 chicken breeds, Rhode Island Red (RIR) and Australorp (AUS), and 2 feeds, mixed feed and fermented feed. A total of 40 eggs were collected at 33 wk of age (0 mo under mixed feed) and 1, 1.5, and 2 mo after switching to fermented feed. Two-way ANOVA mixed design was used to evaluate 10 egg traits: weight, length of the long axis, length of the short axis, eggshell weight, yolk weight, albumen weight, eggshell thickness, eggshell lightness, redness, and yellowness, and 19 yolk amino acids. The results revealed significant breed effects on eggshell redness and yellowness, with higher values of these traits in RIR eggs compared with AUS eggs. There was a significant effect of feed on eggshell lightness, with a lighter color observed under fermented feed compared with mixed feed. Significant effects of breed and breed × feed were found for yolk cysteine content. Eggs from AUS had a higher yolk cysteine content than those from RIR. The cysteine content in AUS eggs increased gradually after starting fermented feed, although RIR remained relatively constant over time. These findings suggest that it is possible to produce designer eggs with enriched components, including yolk amino acids, by adjusting both genetic and environmental factors. This represents a first step in understanding the mechanisms underlying the production of value-added eggs in chickens.

Geochemical constraints on the origin of late Cenozoic basalts in the Mt. Changbai volcanic field, NE China: evidence for crustal recycling

ABSTRACT We conducted a systematic geochemical study of the Mt. Changbai basalts (MCBs) in NE China to better constrain their mantle sources and petrogenesis. The MCBs display ocean island basalt-like trace element patterns (e.g., positive Nb–Ta anomalies) and variable MgO contents (3.2–10.0 wt.%), trace element ratios (e.g., Ba/Nb and Rb/Nb), and Sr–Nd–Pb–Hf isotopic ratios (87Sr/86Sr(i) = 0.704497–0.705629; εNd(i) = – 2.8 to +3.3; 206Pb/204Pb(i) = 16.9–18.1; εHf = −1.2 to +6.2), which indicate derivation from a heterogeneous mantle source. The least evolved samples (MgO > 7 wt.%), with moderate Fe/Mn and FC3MS (defined as FeOT/CaO – 3MgO/SiO2) values, require a hybrid pyroxenite–peridotite mantle source. The isotopic compositions indicate the mantle source is a mixture between depleted mid-ocean ridge basalt mantle and two enriched mantle components. Our geochemical and published geophysical data indicate that these two enriched components are recycled ancient sediments and Pacific oceanic crust, which were derived from the mantle transition zone. An upwelling wet plume from the mantle transition zone transported these two enriched components into the asthenospheric mantle. These enriched components were then transformed into pyroxenite and/or eclogite through melt–rock reaction or mechanical mixing with asthenospheric mantle peridotite. We further propose that partial melting of this heterogeneous asthenospheric mantle containing fusible pyroxenite and/or eclogite (i.e., the enriched components) and refractory peridotite produced the MCBs.

Untargeted multi-omic analysis of colorectal cancer-specific exosomes reveals joint pathways of colorectal cancer in both clinical samples and cell culture.

Exosomes are naturally secreted nano-vesicles consisting of biochemical molecules including RNAs, metabolites, lipids, and proteins, that emerge as diagnostic tools and disease-specific reporters. Here we offer a systematic and integrative approach for the simultaneous analysis of altered molecules namely metabolites, lipids, and proteins. These components tend to augment the discovery of low abundance signature components, and assist in explanation of molecular basis of colorectal cancer (CRC). In order to investigate CRC-derived exosomes, we selected mi-R19a, miR-21, miR-92a, and miR-1246 positive exosomes for downstream experiments. The overall multi-omic changes were investigated comparatively in cell culture and serum samples. Following a systematic multi-omic study, 37 (cell culture) and 31 (serum) metabolites; 130 (cell culture) and 56 (serum) lipids; 9 (cell culture) and 13 (serum) proteins were seen to be differentially expressed (p < 0.05), enabling discrimination between CRC and control. By using these enriched components, we demonstrated that the joint pathways mainly involving fatty acid and amino acid metabolism related pathways changed in CRC significantly. We conclude that this study increases our understanding of molecular basis of CRC, and provides potential exosomal biomarkers for the non-invasive detection, and discrimination of CRC.