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Herein, we provide a novel method for the synthesis of 1,3-dibenzenesulfonylpolysulfane (DBSPS), which further reacts with boronic acids to afford thiosulfonates. Commercially available boron compounds greatly expanded the range of thiosulfonates. Experimental and theoretical mechanistic investigations suggested that DBSPS could provide both thiosulfone fragments and dithiosulfone fragments, but the generated aryl dithiosulfonates were unstable and decomposed into thiosulfonates.
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After ovulation, the mitochondrial enzyme CYP11A1 cleavage the cholesterol into pregnenolone for progesterone synthesis, suggesting that mitochondrial dynamics play a vital role in the female reproductive system. The changes in the mitochondria dynamics throughout the ovarian cycle have been reported in literature, but the correlation to its role in the ovarian cycle remains unclear. In this study, mitochondrial fusion promotor, M1, was used to study the impact of mitochondria dynamics in the female reproductive system. Our results showed that M1 treatment in mice can lead to the disruptions of estrous cycles in vagina smears. The decrease in serum LH was recorded in the animal. And the inhibitions of progesterone secretion and ovulations were observed in ovarian culture. Although no significant changes in mitochondrial networks were observed in the ovaries, significant up-regulation of mitochondrial respiratory complexes was revealed in M1 treatments through transcriptomic analysis. In contrast to the estrogen and steroid biosynthesis up-regulated in M1, the molecules of extracellular matrix, remodeling enzymes, and adhesion signalings were decreased. Collectively, our study provides novel targets to regulate the ovarian cycles through the mitochondria. However, more studies are still necessary to provide the functional connections between mitochondria and the female reproductive systems.
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Dinâmica Mitocondrial , Progesterona , Camundongos , Feminino , Animais , Proestro , Ciclo Estral/fisiologia , Ovário , EstradiolRESUMO
Long-read sequencing (LRS) facilitates both the genome assembly and the discovery of structural variants (SVs). Here, we built a graph-based pig pangenome by incorporating 11 LRS genomes with an average of 94.01% BUSCO completeness score, revealing 206-Mb novel sequences. We discovered 183,352 nonredundant SVs (63% novel), representing 12.12% of the reference genome. By genotyping SVs in an additional 196 short-read sequencing samples, we identified thousands of population stratified SVs. Particularly, we detected 7,568 Tibetan specific SVs, some of which demonstrate significant population differentiation between Tibetan and low-altitude pigs, which might be associated with the high-altitude hypoxia adaptation in Tibetan pigs. Further integrating functional genomic data, the most promising candidate genes within the SVs that might contribute to the high-altitude hypoxia adaptation were discovered. Overall, our study generates a benchmark pangenome resource for illustrating the important roles of SVs in adaptive evolution, domestication, and genetic improvement of agronomic traits in pigs.
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Aims: Studies have observed changes in autophagic flux in the adipose tissue of type 2 diabetes patients with obesity. However, the role of autophagy in obesity-induced insulin resistance is unclear. We propose to confirm the effect of a high-fat diet (HFD) on autophagy and insulin signaling transduction from adipose tissue to clarify whether altered autophagy-mediated HFD induces insulin resistance, and to elucidate the possible mechanisms in autophagy-regulated adipose insulin sensitivity. Methods: Eight-week-old male C57BL/6 mice were fed with HFD to confirm the effect of HFD on autophagy and insulin signaling transduction from adipose tissue. Differentiated 3T3-L1 adipocytes were treated with 1.2 mM fatty acids (FAs) and 50 nM Bafilomycin A1 to determine the autophagic flux. 2.5 mg/kg body weight dose of Chloroquine (CQ) in PBS was locally injected into mouse epididymal adipose (10 and 24 h) and 40 µM of CQ to 3T3-L1 adipocytes for 24 h to evaluate the role of autophagy in insulin signaling transduction. Results: The HFD treatment resulted in a significant increase in SQSTM1/p62, Rubicon expression, and C/EBP homologous protein (CHOP) expression, yet the insulin capability to induce Akt (Ser473) and GSK3ß (Ser9) phosphorylation were reduced. PHLPP1 and PTEN remain unchanged after CQ injection. In differentiated 3T3-L1 adipocytes treated with CQ, although the amount of phospho-Akt stimulated by insulin in the CQ-treated group was significantly lower, CHOP expressions and cleaved caspase-3 were increased and bafilomycin A1 induced less accumulation of LC3-II protein. Conclusion: Long-term high-fat diet promotes insulin resistance, late-stage autophagy inhibition, ER stress, and apoptosis in adipose tissue. Autophagy suppression may not affect insulin signaling transduction via phosphatase expression but indirectly causes insulin resistance through ER stress or apoptosis.
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BACKGROUND: It has been previously demonstrated that hyaluronan (HA) potentially regulates the initiation and propagation of bladder cancer (BLCA). HYAL3 encodes hyaluronidase and is a potential therapeutic target for BLCA. We aimed to explore the role that HYAL3 plays in BLCA pathogenesis. METHODS: HYAL3 expression in BLCA specimens was analyzed using The Cancer Genome Atlas (TCGA) database and the Gene Expression Omnibus (GEO) cohort as well as confirmed in cell lines and The Human Protein Atlas. Then, associations between HYAL3 expression and clinicopathological data were analyzed using survival curves and receiver-operating characteristic (ROC) curves. The functions of HYAL3 were further dissected using Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and the protein-protein interaction network. Finally, we harnessed the Tumor IMmune Estimation Resource and Gene Expression Profiling Interactive Analysis to obtain correlations between HYAL3 expression, infiltrating immunocytes, and the corresponding immune marker sets. RESULTS: HYAL3 expression varied greatly between many types of cancers. In addition, a higher HYAL3 expression level predicted a poor overall survival (OS) in both TCGA-BLCA and GEO gene chips (P < 0.05). HYAL3 also exhibited an acceptable diagnostic ability for the pathological stage of BLCA (area under the receiver-operating characteristic curve = 0.769). Furthermore, HYAL3 acted as an independent prognostic factor in BLCA patients and correlated with the infiltration of various types of immunocytes, including B cells, CD8+ T cells, cytotoxic cells, T follicular helper cells, and T helper (Th) 2 cells. CONCLUSION: HYAL3 might serve as a potential biomarker for predicting poor OS in BLCA patients and correlated with immunocyte infiltration in BLCA.
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Neoplasias da Bexiga Urinária , Biomarcadores Tumorais/genética , Linfócitos T CD8-Positivos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Neoplasias da Bexiga Urinária/genéticaRESUMO
White spot syndrome virus (WSSV) has been reported to cause severe economic loss in the shrimp industry. With WSSV being a large virus still under investigation, the 3D structure of its assembly remains unclear. The current study was planned to clarify the 3D structures of WSSV infections in the cell nucleus of red swamp crayfish (Procambarus clarkii). The samples from various tissues were prepared on the seventh day post-infection. The serial sections of the intestinal tissue were obtained for electron tomography after the ultrastructural screening. After 3D reconstruction, the WSSV-associated structures were further visualized, and the expressions of viral proteins were confirmed with immuno-gold labeling. While the pairs of sheet-like structures with unknown functions were observed in the nucleus, the immature virions could be recognized by the core units of nucleocapsids on a piece of the envelope. The maturation of the particle could include the elongation of core units and the filling of empty nucleocapsids with electron-dense materials. Our observations may bring to light a possible order of WSSV maturation in the cell nucleus of the crayfish, while more investigations remain necessary to visualize the detailed viral-host interactions.
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Nicotinamide adenine dinucleotide (NAD) is a critical cosubstrate for enzymes involved in supplying energy to the brain. Nicotinamide riboside (NR), an NAD+ precursor, emerges as a neuroprotective factor after chronic brain insults. However, researchers have not determined whether it improves cognition after acute ischemia. In the present study, mice with middle cerebral artery occlusion were treated with NR chloride (NRC, 300 mg/kg, IP., 20 min after reperfusion). The results of the Morris water maze test revealed better recovery of learning and memory function in the NRC-treated group. Acute NRC treatment decreased hippocampal infarct volume, reduced neuronal loss and apoptosis in the hippocampus. Western blot and high-performance liquid chromatography assays of hippocampal tissues revealed that the activation of Sirtin-1 and adenosine 5' monophosphate-activated protein kinase was increased, the NAD content was elevated, and the production of adenosine triphosphate was strengthened by NRC. Collectively, acute NRC treatment increased the energy supply, reduced the neuronal loss and apoptosis, protected the hippocampus and ultimately promoted the recovery of cognitive function after brain ischemia.
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Cloretos , NAD , Animais , Cognição , Hipocampo/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Camundongos , NAD/metabolismo , Niacinamida/análogos & derivados , Compostos de PiridínioRESUMO
Positive-stranded RNA viruses modify host organelles to form replication organelles (ROs) for their own replication. The enteroviral 3A protein has been demonstrated to be highly associated with the COPI pathway, in which factors operate on the ER-to-Golgi intermediate and the Golgi. However, Sar1, a COPII factor exerting coordinated action at endoplasmic reticulum (ER) exit sites rather than COPI factors, is required for the replication of foot-and-mouth disease virus (FMDV). Therefore, further understanding regarding FMDV 3A could be key to explaining the differences and to understanding FMDV's RO formation. In this study, FMDV 3A was confirmed as a peripheral membrane protein capable of modifying the ER into vesicle-like structures, which were neither COPII vesicles nor autophagosomes. When the C-terminus of 3A was truncated, it was located at the ER without vesicular modification. This change was revealed using mGFP and APEX2 fusion constructs, and observed by fluorescence microscopy and electron tomography, respectively. For the other 3A truncation, the minimal region for modification was aa 42-92. Furthermore, we found that the remodeling was related to two COPII factors, Sar1 and Sec12; both interacted with 3A, but their binding domains on 3A were different. Finally, we hypothesized that the N-terminus of 3A would interact with Sar1, as its C-terminus simultaneously interacted with Sec12, which could possibly enhance Sar1 activation. On the ER membrane, active Sar1 interacted with regions of aa 42-59 and aa 76-92 from 3A for vesicle formation. This mechanism was distinct from the traditional COPII pathway and could be critical for FMDV RO formation.
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Vírus da Febre Aftosa , Proteínas Monoméricas de Ligação ao GTP , Animais , Complexo I de Proteína do Envoltório/metabolismo , Retículo Endoplasmático/metabolismo , Vírus da Febre Aftosa/fisiologia , Complexo de Golgi/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Transporte Proteico/fisiologiaRESUMO
OBJECTIVES: Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive method that activates peripheral nerves and enhances muscle strength. This study aimed to investigate the effect of rPMS applied in early subacute stroke on severe upper extremity impairment. DESIGN: Randomized controlled trial. SETTING: Rehabilitation department of a university hospital. SUBJECTS: People aged 30-80 years with no practical arm function within four weeks of a first stroke. INTERVENTIONS: Participants were randomly assigned to either the rPMS group (n = 24, 20Hz and 2400 pulses of rPMS to triceps brachii and extensor digitorum muscles daily for two weeks in addition to conventional physiotherapy) or the control group (n = 20, conventional physiotherapy). MAIN MEASURES: The primary outcome was the upper extremity motor section of Fugl-Meyer Assessment after treatment. Secondary outcomes included Barthel Index and root mean square of surface electromyography for muscle strength and stretch-induced spasticity of critical muscles of the upper extremity. Data presented: mean (SD) or median (IQR). RESULTS: The rPMS group showed more significant improvements in the Fugl-Meyer Assessment (12.5 (2.5) vs. 7.0 (1.4), P < 0.001), Barthel Index (15 (5) vs. 10 (3.7), P < 0.001), and strength-root mean square (biceps brachii: 20.5 (4.8) vs. 6.2 (2.7), p < 0.001; triceps brachii: 14.9 (5.8) vs. 4.3 (1.2), p < 0.001; flexor digitorum: 5.1 (0.8) vs. 4.0 (1.1), p < 0.001) compared with the control group. CONCLUSION: In patients with no functional arm movement, rPMS of upper limb extensors improves arm function and muscle strength for grip and elbow flexion and extension.
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Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Fenômenos Magnéticos , Pessoa de Meia-Idade , Espasticidade Muscular , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Extremidade SuperiorRESUMO
Galectin-1 is found in the vasculature and has been confirmed to promote angiogenesis in several cancer models. Furthermore, galectin-1 has been demonstrated to improve the recovery of cerebral ischemia. However, whether vascular remodeling contributes to this improvement is still unknown. In the present study, photochemical cerebral ischemia was induced in both galectin-1-treated (2 µg/day, i.c.v, 3 days) and galectin-1 knockout mice. Laser speckle imaging and immunofluorescent staining demonstrated that circulation and vascular remodeling in the ischemic cortex were improved by galectin-1 treatment but disrupted in galectin-1 knockout mice. Western blot analysis showed that the expression of matrix metallopeptidase-9 and vascular endothelial growth factor (VEGF) was regulated by galectin-1 in vivo. To determine how galectin-1 influences endothelial cells, the expression of galectin-1 in bEnd.3 cells was increased by transfection with an expression plasmid and knocked down by siRNA. As demonstrated by quantitative RT-PCR and western blot analysis, the expression of metallopeptidase-9, VEGF, and VEGF receptors was upregulated by galectin-1 overexpression but downregulated after galectin-1 knockdown. Flow cytometry, Transwell assay, and capillary-like tube formation assay were performed on cells after gene manipulation as well as cells treated by exogenous galectin-1 after anoxia. It demonstrated that galectin-1 potentiated the cell proliferation, migration capacity, and tube formation ability. Taken together, these data suggest that by targeting vascular remodeling, galectin-1 contributes to the restoration of blood flow, which promotes the recovery of mice after cerebral ischemic insults.
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Isquemia Encefálica , Fator A de Crescimento do Endotélio Vascular , Animais , Isquemia Encefálica/metabolismo , Infarto Cerebral/metabolismo , Células Endoteliais/metabolismo , Galectina 1/genética , Galectina 1/metabolismo , Isquemia , Camundongos , Camundongos Knockout , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Remodelação VascularRESUMO
Background: To explore the clinical significance of miR-125b-5p and its potential mechanisms in lung squamous cell carcinoma (LUSC). Materials and Methods: An integrated analysis of data from in-house quantitative real-time polymerase chain reaction (qRT-PCR), microRNA-sequencing, and microarray assays to appraise the expression level of miR-125b-5p in LUSC tissues compared to adjacent noncancerous controls. The authors identified the candidate targets of miR-125b-5p and conducted functional analysis using computational biology strategies from gene ontology, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, disease ontology (DO), and protein-protein interaction (PPI) network analyses to investigate the prospective mechanisms. Results: According to qRT-PCR results, the expression level of miR-125b-5p was markedly decreased in LUSC tissues compared to noncancerous control tissues. Receiver operating characteristic and summary receiver operating characteristic analyses showed that miR-125b-5p had good specificity and sensitivity for distinguishing LUSC tissue from noncancerous lung tissue. The standard mean difference revealed that men and women with lower expression levels of miR-125b-5p may have a higher risk for LUSC. KEGG analysis and DO analysis intimated that target genes were evidently enriched in pyrimidine metabolism and pancreatic carcinoma. The PPI network of the top assembled KEGG pathway indicated that RRM2, UMPS, UCK2, and CTPS1 were regarded as crucial target genes for miR-125b-5p, and RRM2 was eventually deemed a key target. Conclusions: The authors' findings implicate a low expression level of miR-125b-5p in LUSC. A tumor-suppressive role of miR-125b-5p is proposed, based on its effects on LUSC tumor growth, clinical stage progression, and lymph node metastasis.
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Carcinoma de Células Escamosas , Neoplasias Pulmonares , MicroRNAs , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
Whether the doped t-J model on the Kagome lattice supports exotic superconductivity has not been decisively answered. In this Letter, we propose a new class of variational states for this model and perform a large-scale variational Monte Carlo simulation on it. The proposed variational states are parameterized by the SU(2)-gauge rotation angles, as the SU(2)-gauge structure hidden in the Gutzwiller-projected mean-field Ansatz for the undoped model is broken upon doping. These variational doped states smoothly connect to the previously studied U(1) π-flux or 0-flux states, and energy minimization among them yields a chiral noncentrosymmetric nematic superconducting state with 2×2-enlarged unit cell. Moreover, this pair density wave state possesses a finite Fermi surface for the Bogoliubov quasiparticles. We further study experimentally relevant properties of this intriguing pairing state.
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A visible-light-triggered radical cascade sulfonylation/aryl migration/desulfonylation and C-S/Se bond formation reaction of butenyl benzothiazole sulfone with thiosulfonates or selenosulfonates is developed. This study affords the 1,2,4-trifunctionalization of butenyl benzothiazole sulfone derivatives under mild conditions.
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Hypoxia and angiogenesis play key roles in the pathogenesis of esophageal squamous cell carcinoma (ESCC), but regulators linking these two pathways to drive tumor progression remain elusive. Here we provide evidence of ADAM9's novel function in ESCC progression. Increasing expression of ADAM9 was correlated with poor clinical outcomes in ESCC patients. Suppression of ADAM9 function diminished ESCC cell migration and in vivo metastasis in ESCC xenograft mouse models. Using cellular fractionation and imaging, we found a fraction of ADAM9 was present in the nucleus and was uniquely associated with gene loci known to be linked to the angiogenesis pathway demonstrated by genome-wide ChIP-seq. Mechanistically, nuclear ADAM9, triggered by hypoxia-induced translocation, functions as a transcriptional repressor by binding to promoters of genes involved in the negative regulation of angiogenesis, and thereby promotes tumor angiogenesis in plasminogen/plasmin pathway. Moreover, ADAM9 suppresses plasminogen activator inhibitor-1 gene transcription by interacting with its transcription factors at the promoter. Our findings uncover a novel regulatory mechanism of ADAM9 as a transcriptional regulator in angiogenesis and highlight ADAM9 as a promising therapeutic target for ESCC treatment.
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Proteínas ADAM/fisiologia , Neoplasias Esofágicas/irrigação sanguínea , Carcinoma de Células Escamosas do Esôfago/irrigação sanguínea , Proteínas de Membrana/fisiologia , Neovascularização Patológica/fisiopatologia , Fatores de Transcrição/fisiologia , Animais , Movimento Celular , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Camundongos , Camundongos SCID , Neovascularização Patológica/genética , Inibidor 1 de Ativador de Plasminogênio/genética , Prognóstico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In mammalian ovaries, mitochondria are integral sites of energy production and steroidogenesis. While shifts in cellular activities and steroidogenesis are well characterized during the differentiation of large luteal cells in folliculogenesis and luteal formation, mitochondrial dynamics during this process have not been previously evaluated. In this study, we collected ovaries containing primordial follicles, mature follicles, corpus hemorrhagicum, or corpus luteum from goats at specific times in the estrous cycle. Enzyme histochemistry, ultrastructural observations, and 3D structural analysis of serial sections of mitochondria revealed that branched mitochondrial networks were predominant in follicles, while spherical and tubular mitochondria were typical in large luteal cells. Furthermore, the average mitochondrial diameter and volume increased from folliculogenesis to luteal formation. In primordial follicles, the signals of cytochrome c oxidase and ATP synthase were undetectable in most cells, and the large luteal cells from the corpus hemorrhagicum also showed low enzyme signals and content when compared with granulosa cells in mature follicles or large luteal cells from the corpus luteum. Our findings suggest that the mitochondrial enlargement could be an event during folliculogenesis and luteal formation, while the modulation of mitochondrial morphology and respiratory enzyme expressions may be related to tissue remodeling during luteal formation.
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Lipogênese/fisiologia , Células Lúteas/metabolismo , Animais , Feminino , Cabras , Dinâmica Mitocondrial/fisiologiaRESUMO
During the spring, an outbreak of sudden death involving 58 birds occurred in a zoo. Histopathological examinations revealed variable numbers of intracytoplasmic basophilic microorganisms in the macrophages, hepatocytes, and renal epithelium of most birds, along with occasional botryoid intracytoplasmic inclusion bodies within histiocytes in the bursa of Fabricius. Based on the results of histopathological examinations, immunohistochemical staining, transmission electron microscopy, and polymerase chain reactions, genotype B Chlamydia psittaci infection concurrent with pigeon circovirus (PiCV) was diagnosed. A retrospective survey, including two years before the outbreak and the outbreak year, of C. psittaci and PiCV infections of dead birds in the aviaries, revealed that the outbreak was an independent episode. The findings of this study indicate that concurrent infection with C. psittaci and PiCV might lead to lethal outbreaks of chlamydiosis, particularly Streptopelia orientalis. In addition, persistently monitoring both pathogens and identifying potential PiCV carriers or transmitters might also help prevent lethal disease outbreaks.
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Obese men have lower circulating testosterone than men with an optimal body mass index. Elevated fatty acids (FAs) caused by obesity have been reported to suppress the steroidogenesis of Leydig cells. Recent studies have demonstrated that autophagy regulates steroidogenesis in endocrine cells; however, few studies have investigated the molecular mechanisms of FA-impaired steroidogenesis. To study FA regulation in the steroidogenesis of Leydig cells, MA-10 cells were treated with an FA mixture and co-treated with 8-Br-cAMP to stimulate the steroidogenesis capacity. We showed that FAs led to cellular lipid accumulation and decreased steroidogenesis of MA-10 cells, and FA-suppressed steroidogenesis was largely recovered by P5 treatment but not by 22R-OHC treatment, suggesting the primary defect was the deficiency of CYP11A1. To examine the involvement of autophagy in the steroidogenesis of Leydig cells, we treated MA-10 cells with autophagy regulators, including rapamycin, bafilomycin, and chloroquine. Inhibition of late-stage autophagy including FA-upregulated Rubicon suppressed the steroidogenesis of MA-10 cells. More interestingly, Rubicon played a novel regulatory role in the steroidogenesis of MA-10 cells, independent of inhibitors of late-stage autophagy. Collectively, this study provides novel targets to investigate the interaction between FAs and steroidogenesis in steroidogenic cells.
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Autofagia/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Ácidos Graxos/metabolismo , Esteroides/metabolismo , Animais , Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Células Endócrinas/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Lipídeos/genética , Macrolídeos/farmacologia , Masculino , Camundongos , Obesidade/genética , Obesidade/metabolismo , Obesidade/patologia , Sirolimo/farmacologia , Esteroides/biossínteseRESUMO
The spin- 1 2 kagome antiferromagnet is considered an ideal host for a quantum spin liquid (QSL) ground state. We find that when the bonds of the kagome lattice are modulated with a periodic pattern, new quantum ground states emerge. Newly synthesized crystalline barlowite (Cu4(OH)6FBr) and Zn-substituted barlowite demonstrate the delicate interplay between singlet states and spin order on the spin- 1 2 kagome lattice. Comprehensive structural measurements demonstrate that our new variant of barlowite maintains hexagonal symmetry at low temperatures with an arrangement of distorted and undistorted kagome triangles, for which numerical simulations predict a pinwheel valence bond crystal (VBC) state instead of a QSL. The presence of interlayer spins eventually leads to an interesting pinwheel q = 0 magnetic order. Partially Zn-substituted barlowite (Cu3.44Zn0.56(OH)6FBr) has an ideal kagome lattice and shows QSL behavior, indicating a surprising robustness of the QSL against interlayer impurities. The magnetic susceptibility is similar to that of herbertsmithite, even though the Cu2+ impurities are above the percolation threshold for the interlayer lattice and they couple more strongly to the nearest kagome moment. This system is a unique playground displaying QSL, VBC, and spin order, furthering our understanding of these highly competitive quantum states.
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It has long been proposed that doping a chiral spin liquid (CSL) or fractional quantum Hall state can give rise to topological superconductivity. Despite intensive effort, definitive evidences still remain lacking. We address this problem by studying the t-J model supplemented by time-reversal symmetry breaking chiral interaction J_{χ} on the triangular lattice using density-matrix renormalization group with a finite concentration δ of doped holes. It has been established that the undoped, i.e., δ=0, system has a CSL ground state in the parameter region 0.32≤J_{χ}/J≤0.56. Upon light doping, we find that the ground state of the system is consistent with a Luther-Emery liquid with power-law superconducting and charge-density-wave correlations but short-range spin-spin correlations. In particular, the superconducting correlations, whose pairing symmetry is consistent with d±id wave, are dominant at all hole doping concentrations. Our results provide direct evidences that doping the CSL on the triangular lattice can naturally give rise to topological superconductivity.