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The relationship between initial Homo sapiens dispersal from Africa to East Asia and the orbitally paced evolution of the Asian summer monsoon (ASM)-currently the largest monsoon system-remains underexplored due to lack of coordinated synthesis of both Asian paleoanthropological and paleoclimatic data. Here, we investigate orbital-scale ASM dynamics during the last 280 thousand years (kyr) and their likely influences on early H. sapiens dispersal to East Asia, through a unique integration of i) new centennial-resolution ASM records from the Chinese Loess Plateau, ii) model-based East Asian hydroclimatic reconstructions, iii) paleoanthropological data compilations, and iv) global H. sapiens habitat suitability simulations. Our combined proxy- and model-based reconstructions suggest that ASM precipitation responded to a combination of Northern Hemisphere ice volume, greenhouse gas, and regional summer insolation forcing, with cooccurring primary orbital cycles of ~100-kyr, 41-kyr, and ~20-kyr. Between ~125 and 70 kyr ago, summer monsoon rains and temperatures increased in vast areas across Asia. This episode coincides with the earliest H. sapiens fossil occurrence at multiple localities in East Asia. Following the transcontinental increase in simulated habitat suitability, we suggest that ASM strengthening together with Southeast African climate deterioration may have promoted the initial H. sapiens dispersal from their African homeland to remote East Asia during the last interglacial.
Assuntos
Povo Asiático , Migração Humana , Tempo (Meteorologia) , Humanos , África , Ásia , Ásia OrientalRESUMO
Whether there are links between geomagnetic field and Earth's orbital parameters remains unclear. Synchronous reconstructions of parallel long-term quantitative geomagnetic field and climate change records are rare. Here, we present 10Be-derived changes of both geomagnetic field and Asian monsoon (AM) rainfall over the last 870 kyr from the Xifeng loess-paleosol sequence on the central Chinese Loess Plateau. The 10BeGM flux (a proxy for geomagnetic field-induced 10Be production rate) reveals 13 consecutive geomagnetic excursions in the Brunhes chron, which are synchronized with the global records, providing key time markers for Chinese loess-paleosol sequences. The 10Be-derived rainfall exhibits distinct ~100 kyr glacial-interglacial cycles, and superimposed precessional (~23 kyr) cycles that match with those in Chinese speleothem δ18O record. We find that changes in the geomagnetic field and AM rainfall share a common ~100 kyr cyclicity, implying a likely eccentricity modulation of both the geomagnetic field and climate.
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China has a long history of pig breeding and a number of local breeds. The Songliao Black pig, bred in China in 2009, shows high variation in backfat thickness and therefore is well-suited to fat deposition research. Fat deposition is a complex trait, and the underlying regulatory factors are not fully characterized. In this study, the molecular basis of fat deposition traits was evaluated by comparisons between three individuals with extremely high-backfat thickness and three with extremely low-backfat thickness selected from 53 gilts. Subcutaneous adipose tissues of the back were collected for strand-specific library RNA sequencing (RNA-seq) and small RNA-seq. We identified 13 184 mRNAs, 2046 long non-coding (lnc)RNAs, and 494 micro (mi)RNAs by high-throughput sequencing. Furthermore, we detected 150 differentially expressed mRNAs, 66 differentially expressed lncRNAs, and eight differentially expressed miRNAs. A functional enrichment analysis indicated that these genes are involved in multiple fat metabolism-related pathways, including positive regulation of fat cell differentiation, and fat digestion and absorption. We used various algorithms (miRanda, TargetScan, and RNAhybrid) to predict targeting relationships and constructed a competing endogenous RNA network containing seven lncRNAs, three miRNAs, and six mRNAs. All these genes were differentially expressed between the extremely high and low backfat thickness groups or enriched in pathways related to fat metabolism. Our results provide insight into the regulatory mechanisms by which non-coding RNAs and their target genes influence backfat deposition in pigs. Furthermore, our newly constructed competing endogenous RNA (lncRNA-miRNA-mRNA) network provides a basis for further exploration of fat deposition traits and non-coding RNA functions.
Assuntos
MicroRNAs , RNA Longo não Codificante , Suínos/genética , Animais , Feminino , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , Redes Reguladoras de Genes , Sus scrofa/genética , Sus scrofa/metabolismoRESUMO
Gold nanoclusters (AuNCs) have shown promising applications in biotherapy owing to their ultrasmall size and unique molecular-like properties. In order to better guide the preparations and applications of AuNCs, dihydrolipoic acid-protected AuNCs (DHLA-AuNCs) and glutathione-protected AuNCs (GSH-AuNCs) were selected as models and the interactions between them and calf thymus DNA (ctDNA) were studied in detail. The results showed that there was a small difference in the binding mechanisms and forces between both AuNCs and ctDNA. The quenching mechanisms of both AuNCs to (ctDNA-HO) were completely different. The binding constants indicated that the binding strength between DHLA-AuNCs and ctDNA was greater than those of GSH-AuNCs. The conformation investigations showed that GSH-AuNCs had a greater impact on the conformation of ctDNA, and both AuNCs were more inclined to interact with the A-T base pairs of ctDNA. These results indicate that the surface ligand had a significant effect on the interactions between AuNCs and DNA and might also further affect the applications of AuNCs, and these results could guide the preparations of AuNCs. For DHLA-AuNCs, their good biocompatibility made them a potential candidate for application in imaging, drug treatment, sensing, and so on. The resulting base accumulation of ctDNA and weak interactions made GSH-AuNCs have great potential for application in gene therapy, which was consistent with the current reports on the applications of these two AuNCs. This work has pointed out the directions for the preparations and applications of AuNCs.
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Nanopartículas Metálicas , Preparações Farmacêuticas , Glutationa , OuroRESUMO
During RNA viruses's replication, double-stranded RNA (dsRNA) is normally produced and induce host innate immune response. Most of gene activation due cytokine mediated but which are due to methylation mediated is still unknown. In the study, DNA methylome was integrated with our previous transcriptome data to investigate the differentially methylated regions and genes using MeDIP-chip technology. We found that the transcriptional expressions of 15, 37 and 18 genes were negatively related with their promoter DNA methylation levels in the cells treated by PolyI:C, Aza-CdR, as well as PolyI:C plus Aza-CdR, respectively, compared with the untreated cells. GO analysis revealed hypo-methylated genes (BNIP3L and CDK9) and a hyper-methylated gene (ZC3HAV1) involved in the host response to viral replication. Our results suggest that these novel genes targeted by DNA methylation can be potential markers relevant to virus replication and host innate immune response to set up a medical model of infectious diseases.
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Azacitidina/farmacologia , Metilação de DNA , Metilases de Modificação do DNA/antagonistas & inibidores , Regulação da Expressão Gênica/efeitos dos fármacos , Rim/metabolismo , RNA de Cadeia Dupla/química , Replicação Viral/genética , Animais , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Genoma , Rim/virologia , Regiões Promotoras Genéticas , Suínos , Transcriptoma , Replicação Viral/efeitos dos fármacosRESUMO
A laboratory experiment was performed to evaluate the potential role of H2S on cadmium (Cd) toxicity in Phlox paniculata L. Seeds pretreated with 0.3, 0.6, 0.9, and 1.2 mM NaHS as a donor of H2S for 24 h and subsequently exposed to 100, 200, and 300 µM CdCl2 for 26 days had significantly higher germination rate compared with Cd alone. Meanwhile, 2-year-old seedlings sprayed with 0.3, 0.6, and 0.9 µM NaHS were grown in soil with 0.3, 0.6, and 1.2 mg/kg CdCl2, respectively. We observed that H2S decreased Cd accumulation in leaves and elevated Cd concentration in roots. Cd toxicity in seedlings resulted in a substantial increase in Cd-induced overproduction of malondialdehyde (MDA), Cd accumulation, and electrolyte leakage. Meanwhile, addition of NaHS increased photosynthetic performance compared with Cd alone. Exogenous H2S significantly elevated biomass, improved antioxidant enzyme activities, and reduced ABA content compared with Cd alone. H2S also plays an important role in the ABA signaling pathway during stress. Notably, NaHS promoted Cd uptake by Phlox paniculate L. from soil. The prediction model of H2S for increasing plant resistance and reducing soil Cd pollution was established by factor analysis method based on comprehensive evaluation of plant stress physiology.
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Sulfeto de Hidrogênio , Antioxidantes , Biodegradação Ambiental , Cádmio , Malondialdeído , Raízes de Plantas , PlântulaRESUMO
Cumulus cells secreting steroid hormones have important functions in oocyte development. Several members of the short-chain dehydrogenase/reductase (SDR) family are critical to the biosynthesis of steroid hormones. NADPH-dependent retinol dehydrogenase/reductase ( NRDR), a member of the SDR superfamily, is overexpressed in pig breeds that also show high levels of androstenone. However, the potential functions and regulatory mechanisms of NRDR in pig ovaries have not been reported to date. The present study demonstrated that NRDR is highly expressed in pig ovaries and is specifically located in cumulus granulosa cells. Functional studies showed that NRDR inhibition increased estradiol synthesis. Both pregnant mare serum gonadotropin and human chorionic gonadotropin downregulated the expression of NRDR in pig cumulus granulosa cells. When the relationship between reproductive traits and single-nucleotide polymorphisms (SNPs) of the NRDR gene was examined, we found that two SNPs affected reproductive traits. SNP rs701332503 was significantly associated with a decrease in the total number of piglets born during multiparity, and rs326982309 was significantly associated with an increase in the average birth weight during primiparity. Thus, NRDR has an important role in steroid hormone biosynthesis in cumulus granulosa cells, and NRDR SNPs are associated with changes in porcine reproduction traits.
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Oxirredutases do Álcool , Estradiol/biossíntese , Ovário/enzimologia , Paridade/genética , Polimorfismo de Nucleotídeo Único , Característica Quantitativa Herdável , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Gonadotropina Coriônica/farmacologia , Estradiol/genética , Feminino , Gonadotropinas Equinas/farmacologia , Humanos , Gravidez , SuínosRESUMO
The interaction of granulosa cells (GCs) with oocytes is important to regulate follicle development. The exogenous melatonin promoting the maturation of oocytes by GCs has been approved in pig, however, the transcriptome profile and the functions of the genes regulated by melatonin in GCs have not yet to be fully characterized. In this study, we found melatonin could stimulate the synthesis of estradiol in pig GCs. The RNA-seq was used to explore the effects of melatonin on gene expression, a total of 89 differentially expressed genes (DEGs) were identified. Gene ontology analysis showed DEGs which associated with regulation of cell proliferation, cell cycle, and anti-apoptosis were significantly enriched. The functions of two DEGs, NOTCH2 and FILIP1L, were studied in pig GCs. The results showed that NOTCH2 inhibited the synthesis of estradiol, but FILIP1L promoted the synthesis of estradiol. Furthermore, inhibiting NOTCH2 in granulosa cells cocultured with cumulus-oocyte-complexes had no obvious effect on the maturation of pig oocyte, but could upregulate the cleavage rate of oocyte. We proved that FILIP1L had no effect on the maturation and cleavage of pig oocytes. Our work deepens the understanding of melatonin's effects on GCs and oocyte. The DEGs we found will be beneficial to reveal mechanisms of melatonin acting on GCs and oocytes and design the pharmacological interventions.
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Estradiol/biossíntese , Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Melatonina/farmacologia , Oócitos/efeitos dos fármacos , Animais , Feminino , Células da Granulosa/metabolismo , SuínosRESUMO
The goal of this study was to evaluate the microbial communities in the gut and feces from female finishing Landrace pigs with high and low feed conversion ratio (FCR) by 16S rRNA gene amplicon sequencing. Many potential biomarkers can distinguish between high and low FCR groups in the duodenum, ileum, cecum, colon, and rectum, according to linear discriminant analysis effect sizes. The relative abundance of microbes were tested by Mann-Whitney test between the high and low FCR groups in different organs: Campylobacter, Prevotella and Sphaerochaeta were different in the duodenum (P < 0.05); Sanguibacter, Kingella and Anaeroplasma in jejunum; Anaeroplasma, Arthrobacter, Kingella, Megasphaera and SMB53 in the ileum; Butyricicoccus, Campylobacter, Mitsuokella, and Coprobacillus in the cecum; Lactococcus and Peptococcus in the colon; Staphylococcus in the rectum; and Rothia in feces. The prevalence of microbial genera in certain locations could potentially be used as biomarkers to distinguish between high and low FCR. Functional prediction clustering analysis suggested that bacteria in the hindgut mainly participated in carbohydrate metabolism and amino acid metabolism, and different in the relative abundance of metabolic pathways, as predicted from the microbial taxa present, were identified by comparing the high and low groups of each location. The results may provide insights for the alteration of the intestinal microbial communities to improve the growth rate of pigs.
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Ração Animal/análise , Bactérias/classificação , Biodiversidade , Microbioma Gastrointestinal , Suínos , Aminoácidos/metabolismo , Animais , Bactérias/genética , Metabolismo dos Carboidratos , Ceco/microbiologia , Colo/microbiologia , DNA Bacteriano/genética , Análise Discriminante , Fezes/microbiologia , Feminino , Intestino Delgado/microbiologia , Redes e Vias Metabólicas , Metagenômica , RNA Ribossômico 16S/genéticaRESUMO
The Xujiayao site in the Nihewan Basin (North China) is one of the most important Paleolithic sites in East Asia. Twenty Homo fossils, which were previously assigned to an archaic Homo sapiens group, have been excavated along with more than 30,000 lithic artifacts and â¼5000 mammalian fossil specimens. Dating of the Xujiayao hominin has been pursued since its excavation in the 1970s, but its age has remained controversial because of limitations of the dating techniques that have been applied to available materials. Here, we report new ages for the Xujiayao hominin based on combined electron spin resonance (ESR) dating of quartz in the sediments and high-resolution magnetostratigraphy of the fluvio-lacustrine sequence. The magnetostratigraphy suggests that the upper Matuyama and Brunhes polarity chrons are recorded at Xujiayao. The ESR dating results indicate a pooled average age of 260-370 ka for the Homo-bearing layer, which is consistent with its position within the middle Brunhes normal polarity chron indicated by magnetostratigraphy. This age estimate makes the Xujiayao hominin among the oldest mid-Pleistocene hominins with derived Neanderthal traits in East Asia. This age is consistent with the time when early Denisovans, a sister group of Neanderthals, appeared and colonized eastern Eurasia. Our updated age and the Neanderthal-like traits of the Xujiayao Homo fossils, particularly the Denisovan-like molar teeth, make it possible that the Xujiayao hominin could represent an early Denisovan.
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Espectroscopia de Ressonância de Spin Eletrônica , Fósseis , Hominidae , Animais , China , Humanos , Dente Molar , Homem de Neandertal , Fatores de TempoRESUMO
The synthesis, SAR and preclinical characterization of a series of 6-chloro-N-(2-(4,4-difluoropiperidin-1-yl)-2-(2-(trifluoromethyl)pyrimidin-5-yl)ethyl)quinoline-5-carboxamide based P2X7 antagonists is described herein. The lead compounds are potent inhibitors in Ca(2+) flux and whole blood IL-1ß P2X7 release assays at both human and mouse isoforms. Compound 1e showed a robust reduction of IL-1ß release in a mouse ex vivo model with a 50mg/kg oral dose. Evaluation of compound 1e in the mouse SNI tactile allodynia, carrageenan-induced paw edema or CIA models resulted in no analgesic or anti-inflammatory effects.
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Antagonistas do Receptor Purinérgico P2X/farmacologia , Quinolinas/farmacologia , Animais , Descoberta de Drogas , Humanos , Interleucina-1beta/metabolismo , Camundongos , Antagonistas do Receptor Purinérgico P2X/química , Quinolinas/química , Relação Estrutura-AtividadeRESUMO
The synthesis, SAR, and preclinical characterization of a series of substituted 6,7-dihydro[1,2,4]triazolo[4,3]pyrazin-8(5H)-one P2X7 receptor antagonists are described. Optimized leads from this series comprise some of the most potent human P2X7R antagonists reported to date (IC50s<1nM). They also exhibit sufficient potency and oral bioavailability in rat to enable extensive in vivo profiling. Although many of the disclosed compounds are peripherally restricted, compound 11d is brain penetrant and upon oral administration demonstrated dose-dependent target engagement in rat hippocampus as determined by ex vivo receptor occupancy with radiotracer 5 (ED50=0.8mg/kg).
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Fármacos do Sistema Nervoso Central/farmacologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Pirazinas/farmacologia , Triazóis/farmacologia , Animais , Barreira Hematoencefálica/metabolismo , Células CACO-2 , Fármacos do Sistema Nervoso Central/síntese química , Fármacos do Sistema Nervoso Central/farmacocinética , Hipocampo/metabolismo , Humanos , Microssomos Hepáticos/metabolismo , Antagonistas do Receptor Purinérgico P2X/síntese química , Antagonistas do Receptor Purinérgico P2X/farmacocinética , Pirazinas/síntese química , Pirazinas/farmacocinética , Ratos , Receptores Purinérgicos P2X7/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/farmacocinética , TrítioRESUMO
The biological significance of a known normal and cancer stem cell marker CD133 remains elusive. We now demonstrate that the phosphorylation of tyrosine-828 residue in CD133 C-terminal cytoplasmic domain mediates direct interaction between CD133 and phosphoinositide 3-kinase (PI3K) 85 kDa regulatory subunit (p85), resulting in preferential activation of PI3K/protein kinase B (Akt) pathway in glioma stem cell (GSC) relative to matched nonstem cell. CD133 knockdown potently inhibits the activity of PI3K/Akt pathway with an accompanying reduction in the self-renewal and tumorigenicity of GSC. The inhibitory effects of CD133 knockdown could be completely rescued by expression of WT CD133, but not its p85-binding deficient Y828F mutant. Analysis of glioma samples reveals that CD133 Y828 phosphorylation level is correlated with histopathological grade and overlaps with Akt activation. Our results identify the CD133/PI3K/Akt signaling axis, exploring the fundamental role of CD133 in glioma stem cell behavior.
Assuntos
Antígenos CD/metabolismo , Transformação Celular Neoplásica/metabolismo , Classe Ia de Fosfatidilinositol 3-Quinase/metabolismo , Glioma/fisiopatologia , Glicoproteínas/metabolismo , Células-Tronco Neoplásicas/fisiologia , Peptídeos/metabolismo , Transdução de Sinais/fisiologia , Antígeno AC133 , Animais , Antígenos CD/genética , Western Blotting , Glioma/metabolismo , Glicoproteínas/genética , Humanos , Imunoprecipitação , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação de Sentido Incorreto/genética , Células-Tronco Neoplásicas/metabolismo , Peptídeos/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
With the increasing demands for better transmission speed and robust quality of service (QoS), the capacity constrained backhaul gradually becomes a bottleneck in cooperative wireless networks, e.g., in the Internet of Things (IoT) scenario in joint processing mode of LTE-Advanced Pro. This paper focuses on resource allocation within capacity constrained backhaul in uplink cooperative wireless networks, where two base stations (BSs) equipped with single antennae serve multiple single-antennae users via multi-carrier transmission mode. In this work, we propose a novel cooperative transmission scheme based on compress-and-forward with user pairing to solve the joint mixed integer programming problem. To maximize the system capacity under the limited backhaul, we formulate the joint optimization problem of user sorting, subcarrier mapping and backhaul resource sharing among different pairs (subcarriers for users). A novel robust and efficient centralized algorithm based on alternating optimization strategy and perfect mapping is proposed. Simulations show that our novel method can improve the system capacity significantly under the constraint of the backhaul resource compared with the blind alternatives.
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The optimization efforts that led to a novel series of methyl substituted 1-(5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanones that are potent rat and human P2X7 antagonists are described. These efforts resulted in the discovery of compounds with good drug-like properties that are capable of high P2X7 receptor occupancy in rat following oral administration, including compounds 7n (P2X7 IC50 = 7.7 nM) and 7u (P2X7 IC50 =7 .7 nM). These compounds are expected to be useful tools for characterizing the effects of P2X7 antagonism in models of depression and epilepsy, and several of the compounds prepared are candidates for effective P2X7 PET tracers.
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Antagonistas do Receptor Purinérgico P2X/química , Pirazinas/química , Receptores Purinérgicos P2X7/química , Triazóis/química , Animais , Meia-Vida , Humanos , Microssomos/metabolismo , Ligação Proteica , Antagonistas do Receptor Purinérgico P2X/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacocinética , Ratos , Receptores Purinérgicos P2X7/metabolismo , Relação Estrutura-AtividadeRESUMO
GJ (gap junction) channels mediate direct intercellular communication and play an important role in many physiological processes. Six connexins oligomerize to form a hemichannel and two hemichannels dock together end-to-end to form a GJ channel. Connexin extracellular domains (E1 and E2) have been shown to be important for the docking, but the molecular mechanisms behind the docking and formation of GJ channels are not clear. Recent developments in atomic GJ structure and functional studies on a series of connexin mutants revealed that E1 and E2 are likely to play different roles in the docking. Non-covalent interactions at the docking interface, including hydrogen bonds, are predicted to form between interdocked extracellular domains. Protein sequence alignment analysis on the docking compatible/incompatible connexins indicate that the E1 domain is important for the formation of the GJ channel and the E2 domain is important in the docking compatibility in heterotypic channels. Interestingly, the hydrogen-bond forming or equivalent residues in both E1 and E2 domains are mutational hot spots for connexin-linked human diseases. Understanding the molecular mechanisms of GJ docking can assist us to develop novel strategies in rescuing the disease-linked connexin mutants.
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Junções Comunicantes/fisiologia , Sequência de Aminoácidos , Junções Comunicantes/química , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de AminoácidosRESUMO
Double-stranded RNA (dsRNA) is produced in host cells during viral replication. The effects of DNA demethylation on gene expression in dsRNA transfected swine cells are unclear. The study aims to profile the transcriptome changes which are induced by DNA methyltransferase inhibitor (Aza-CdR) in porcine PK15 cells transfected with viral-like dsRNA (Poly(I:C)). A total of 44, 76 and 952 differentially expressed genes (DEGs) were detected in the cells treated by Poly(I:C) plus Aza-CdR (P+A), Poly(I:C) (P) or Aza-CdR (A) alone compared to the controls (C). Immune response-related pathways are observed in the comparison of A vs. C and P vs. C, and the genes in the pathways were recovered in the comparison of (P+A) vs. C. GO analysis indicated that Aza-CdR has negative regulatory effects on viral reproduction. The results suggest that the stimulant of Poly(I:C) could be regressed by Aza-CdR. These observations provide new insights into the epigenetic regulatory effects on viral replication.
Assuntos
Azacitidina/análogos & derivados , Metilases de Modificação do DNA/antagonistas & inibidores , Poli I-C/farmacologia , RNA de Cadeia Dupla/genética , Transcriptoma/efeitos dos fármacos , Animais , Azacitidina/farmacologia , Linhagem Celular , Decitabina , Genoma , Interferon-alfa/genética , Interferon-alfa/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Sus scrofa , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , TransfecçãoRESUMO
BACKGROUND/AIMS: In this study, a subpopulation of stem-like cells in human high grade serous ovarian carcinomas (ovarian cancer stem cells; OCSCs) were isolated and characterized. METHODS: Primary high-grade serous ovarian carcinoma (HGSC) fresh biopsies were cultured under serum-free conditions to produce floating spheres. Sphere formation assay, including self-renewal, differentiation potential, chemo-resistance, and tumorigenicity were determined in vitro or in vivo. RESULTS: OCSCs overexpressed stem cell genes (Oct-4, Nanog, Sox-2, Bmi-1, Nestin, CD133, CD44, CD24, ALDH1, CD117, and ABCG2). Immunostaining of spheres showed overexpressed Oct-4, Nanog, and Sox-2. These isolated tumor cells expanded as spheroid colonies for more than 30 passages. In contrast, adherent cells expressed high levels of CA125 and CK7. Flow cytometry analysis showed increased CSC markers (CD44, CD24, CD117, CD133, ABCG2, and ALDH1) in the spheroid cell population. OCSCs displayed higher chemoresistance to cisplatin or paclitaxel compared to adherent cells. Moreover, subcutaneous injection of 1 × 104 sphere-forming cells into NOD/SCID mice gave rise to new tumors similar to the original human tumors and could be passaged in mice. CONCLUSION: These results revealed that HGSCs are created and propagated by a small number of undifferentiated tumorigenic cells, and therapeutic targeting of these cells could be beneficial for treatment of HGSCs.
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Separação Celular/métodos , Neoplasias Císticas, Mucinosas e Serosas/patologia , Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/patologia , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Adesão Celular , Autorrenovação Celular , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imunofenotipagem , Camundongos SCID , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Ovarianas/genética , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Esferoides Celulares/patologiaRESUMO
Intensification of northern hemisphere glaciation (iNHG), ~2.7 million years ago (Ma), led to establishment of the Pleistocene to present-day bipolar icehouse state. Here we document evolution of orbital- and millennial-scale Asian winter monsoon (AWM) variability across the iNHG using a palaeomagnetically dated centennial-resolution grain size record between 3.6 and 1.9 Ma from a previously undescribed loess-palaeosol/red clay section on the central Chinese Loess Plateau. We find that the late Pliocene-early Pleistocene AWM was characterized by combined 41-kyr and ~100-kyr cycles, in response to ice volume and atmospheric CO2 forcing. Northern hemisphere ice sheet expansion, which was accompanied by an atmospheric CO2 concentration decline, substantially increased glacial AWM intensity and its orbitally oscillating amplitudes across the iNHG. Superposed on orbital variability, we find that millennial AWM intensity fluctuations persisted during both the warmer (higher-CO2) late Pliocene and colder (lower-CO2) early Pleistocene, in response to both external astronomical forcing and internal climate dynamics.
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The effects of overexpression of the thioredoxin-like protein CDSP32 (Trx CDSP32) on reactive oxygen species (ROS) metabolism in tobacco leaves exposed to cadmium (Cd) were studied by combining physiological measures and proteomics technology. Thus, the number of differentially expressed proteins (DEPs) in plants overexpressing the Trx CDSP32 gene in tobacco (OE) was observed to be evidently lower than that in wild-type (WT) tobacco under Cd exposure, especially the number of down-regulated DEPs. Cd exposure induced disordered ROS metabolism in tobacco leaves. Although Cd exposure inhibited the activities of superoxide dismutase (SOD), catalase (CAT), and l-ascorbate peroxidase (APX) and the expression of proteins related to the thioredoxin-peroxiredoxin (Trx-Prx) pathway, the increase in the activities of peroxidase (POD), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), and glutathione S-transferase (GST) and their protein expression levels played an important role in the physiological response to Cd exposure. Notably, Trx CDSP32 was observed to alleviate the decrease in the expression and activities of SOD and CAT caused by Cd exposure and enhance the function of POD. Trx CDSP32 was observed to increase the H2O2 scavenging capacity of the ascorbic acid-glutathione (AsA-GSH) cycle and Trx-Prx pathway under Cd exposure, and it can especially regulate 2-Cys peroxiredoxin (2-Cys Prx) protein expression and thioredoxin peroxidase (TPX) activity. Thus, overexpression of the Trx CDSP32 gene can alleviate the oxidative damage that occurs in tobacco leaves under Cd exposure by modulating antioxidant defense systems.