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Despite the known causality of copy-number variations (CNVs) to human neurodevelopmental disorders, the mechanisms behind each gene's contribution to the constellation of neural phenotypes remain elusive. Here, we investigated the 7q11.23 CNV, whose hemideletion causes Williams syndrome (WS), and uncovered that mitochondrial dysfunction participates in WS pathogenesis. Dysfunction is facilitated in part by the 7q11.23 protein DNAJC30, which interacts with mitochondrial ATP-synthase machinery. Removal of Dnajc30 in mice resulted in hypofunctional mitochondria, diminished morphological features of neocortical pyramidal neurons, and altered behaviors reminiscent of WS. The mitochondrial features are consistent with our observations of decreased integrity of oxidative phosphorylation supercomplexes and ATP-synthase dimers in WS. Thus, we identify DNAJC30 as an auxiliary component of ATP-synthase machinery and reveal mitochondrial maladies as underlying certain defects in brain development and function associated with WS.
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Complexos de ATP Sintetase/metabolismo , Encéfalo/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Mitocôndrias/metabolismo , Síndrome de Williams/genética , Animais , Encéfalo/crescimento & desenvolvimento , Células Cultivadas , Feminino , Células HEK293 , Proteínas de Choque Térmico HSP40/genética , Humanos , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação OxidativaRESUMO
Ankyrin-repeat proteins with a suppressor of cytokine signaling box (ASB) proteins belong to the E3 ubiquitin ligase family. 18 ASB members have been identified whose biological functions are mostly unexplored. Here, we discovered that ASB3 was essential for hepatocellular carcinoma (HCC) development and high ASB3 expression predicted poor clinical outcomes. ASB3 silencing induced HCC cell growth arrest and apoptosis in vitro and in vivo. Liver-specific deletion of Asb3 gene suppressed diethylnitrosamine (DEN)-induced liver cancer development. Mechanistically, ASB3 interacted with death receptor 5 (DR5), which promoted ubiquitination and degradation of DR5. We further showed that ASB3 knockdown stabilized DR5 and increased the sensitivity of liver cancer cells to the treatment of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in a DR5-dependent manner in cellular and in animal models. In summary, we demonstrated that ASB3 promoted ubiquitination and degradation of DR5 in HCC, suggesting the potential of targeting ASB3 to HCC treatment and overcome TRAIL resistance.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Apoptose , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Ligantes , Neoplasias Hepáticas/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitinação , HumanosRESUMO
Pompe disease is a lysosomal storage disorder that preferentially affects muscles, and it is caused by GAA mutation coding acid alpha-glucosidase in lysosome and glycophagy deficiency. While the initial pathology of Pompe disease is glycogen accumulation in lysosomes, the special role of the lysosomal pathway in glycogen degradation is not fully understood. Hence, we investigated the characteristics of accumulated glycogen and the mechanism underlying glycophagy disturbance in Pompe disease. Skeletal muscle specimens were obtained from the affected sites of patients and mouse models with Pompe disease. Histological analysis, immunoblot analysis, immunofluorescence assay, and lysosome isolation were utilized to analyze the characteristics of accumulated glycogen. Cell culture, lentiviral infection, and the CRISPR/Cas9 approach were utilized to investigate the regulation of glycophagy accumulation. We demonstrated residual glycogen, which was distinguishable from mature glycogen by exposed glycogenin and more α-amylase resistance, accumulated in the skeletal muscle of Pompe disease. Lysosome isolation revealed glycogen-free glycogenin in wild type mouse lysosomes and variously sized glycogenin in Gaa-/- mouse lysosomes. Our study identified that a defect in the degradation of glycogenin-exposed residual glycogen in lysosomes was the fundamental pathological mechanism of Pompe disease. Meanwhile, glycogenin-exposed residual glycogen was absent in other glycogen storage diseases caused by cytoplasmic glycogenolysis deficiencies. In vitro, the generation of residual glycogen resulted from cytoplasmic glycogenolysis. Notably, the inhibition of glycogen phosphorylase led to a reduction in glycogenin-exposed residual glycogen and glycophagy accumulations in cellular models of Pompe disease. Therefore, the lysosomal hydrolysis pathway played a crucial role in the degradation of residual glycogen into glycogenin, which took place in tandem with cytoplasmic glycogenolysis. These findings may offer a novel substrate reduction therapeutic strategy for Pompe disease. © 2024 The Pathological Society of Great Britain and Ireland.
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Doença de Depósito de Glicogênio Tipo II , Glicoproteínas , Humanos , Camundongos , Animais , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/patologia , Doença de Depósito de Glicogênio Tipo II/terapia , Glicogênio/análise , Glicogênio/metabolismo , Glucosiltransferases/metabolismo , Músculo Esquelético/patologia , Lisossomos/metabolismoRESUMO
BACKGROUND: Mutations in the tropomyosin receptor kinase fused (TFG) gene are associated with various neurological disorders, including autosomal recessive hereditary spastic paraplegia (HSP), autosomal dominant hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) and autosomal dominant type of Charcot-Marie-Tooth disease type 2. METHODS: Whole genome sequencing and whole-exome sequencing were used, followed by Sanger sequencing for validation. Haplotype analysis was performed to confirm the inheritance mode of the novel TFG mutation in a large Chinese family with HSP. Additionally, another family diagnosed with HMSN-P and carrying the reported TFG mutation was studied. Clinical data and muscle pathology comparisons were drawn between patients with HSP and patients with HMSN-P. Furthermore, functional studies using skin fibroblasts derived from patients with HSP and patients with HMSN-P were conducted to investigate the pathomechanisms of TFG mutations. RESULTS: A novel heterozygous TFG variant (NM_006070.6: c.125G>A (p.R42Q)) was identified and caused pure HSP. We further confirmed that the well-documented recessively inherited spastic paraplegia, caused by homozygous TFG mutations, exists in a dominantly inherited form. Although the clinical features and muscle pathology between patients with HSP and patients with HMSN-P were distinct, skin fibroblasts derived from both patient groups exhibited reduced levels of autophagy-related proteins and the presence of TFG-positive puncta. CONCLUSIONS: Our findings suggest that autophagy impairment may serve as a common pathomechanism among different clinical phenotypes caused by TFG mutations. Consequently, targeting autophagy may facilitate the development of a uniform treatment for TFG-related neurological disorders.
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Neuropatia Hereditária Motora e Sensorial , Doenças do Sistema Nervoso , Paraplegia Espástica Hereditária , Humanos , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/patologia , Proteínas/genética , Mutação/genética , Linhagem , Paraplegia , Proteínas de Transporte Vesicular/genéticaRESUMO
BACKGROUND & AIMS: Post-hepatectomy liver failure (PHLF) leads to poor prognosis in patients undergoing hepatectomy, with hepatic vascular reconstitution playing a critical role. However, the regulators of hepatic vascular reconstitution remain unclear. In this study, we aimed to investigate the regulatory mechanisms of hepatic vascular reconstitution and identify biomarkers predicting PHLF in patients undergoing hepatectomy. METHODS: Candidate genes that were associated with hepatic vascular reconstitution were screened using adeno-associated virus vectors in Alb-Cre-CRISPR/Cas9 mice subjected to partial hepatectomy. The biological activities of candidate genes were estimated using endothelial precursor transfusion and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) models. The level of candidates was detected in biopsies from patients undergoing ALPPS. Risk factors for PHLF were also screened using retrospective data. RESULTS: Downregulation of Gata3 and upregulation of Ramp2 in hepatocytes promoted the proliferation of liver sinusoidal endothelial cells and hepatic revascularization. Pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor A (VEGFA) played opposite roles in regulating the migration of endothelial precursors from bone marrow and the formation of new sinusoids after hepatectomy. Gata3 restricted endothelial cell function in patient-derived hepatic organoids, which was abrogated by a Gata3 inhibitor. Moreover, overexpression of Gata3 led to higher mortality in ALPPS mice, which was improved by a PEDF-neutralizing antibody. The expression of Gata3/RAMP and PEDF/VEGFA tended to have a negative correlation in patients undergoing ALPPS. A nomogram incorporating multiple factors, such as serum PEDF/VEGF index, was constructed and could efficiently predict the risk of PHLF. CONCLUSIONS: The balance of Gata3 and Ramp2 in hepatocytes regulates the proliferation of liver sinusoidal endothelial cells and hepatic revascularization via changes in the expression of PEDF and VEGFA, revealing potential targets for the prevention and treatment of PHLF. IMPACT AND IMPLICATIONS: In this study, we show that the balance of Gata3 and Ramp2 in hepatocytes regulates hepatic vascular reconstitution by promoting a shift from pigment epithelium-derived factor (PEDF) to vascular endothelial growth factor A (VEGFA) expression during hepatectomy- or ALLPS (associating liver partition and portal vein ligation for staged hepatectomy)-induced liver regeneration. We also identified serum PEDF/VEGFA index as a potential predictor of post-hepatectomy liver failure in patients who underwent hepatectomy. This study improves our understanding of how hepatocytes contribute to liver regeneration and provides new targets for the prevention and treatment of post-hepatectomy liver failure.
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Falência Hepática , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Regeneração Hepática/fisiologia , Fator A de Crescimento do Endotélio Vascular , Estudos Retrospectivos , Células Endoteliais , Fígado/cirurgia , Hepatectomia/efeitos adversos , Hepatócitos/fisiologia , Veia Porta/cirurgia , Falência Hepática/etiologia , Ligadura , Fator de Transcrição GATA3 , Proteína 2 Modificadora da Atividade de ReceptoresRESUMO
Inherited deficiency of thymidine phosphorylase (TP), encoded by TYMP, leads to a rare disease with multiple mitochondrial DNA (mtDNA) abnormalities, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). However, the impact of TP deficiency on lysosomes remains unclear, which are important for mitochondrial quality control and nucleic acid metabolism. Muscle biopsy tissue and skin fibroblasts from MNGIE patients, patients with m.3243 A > G mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and healthy controls (HC) were collected to perform mitochondrial and lysosomal functional analyses. In addition to mtDNA abnormalities, compared to controls distinctively reduced expression of LAMP1 and increased mitochondrial content were detected in the muscle tissue of MNGIE patients. Skin fibroblasts from MNGIE patients showed decreased expression of LAMP2, lowered lysosomal acidity, reduced enzyme activity and impaired protein degradation ability. TYMP knockout or TP inhibition in cells can also induce the similar lysosomal dysfunction. Using lysosome immunoprecipitation (Lyso- IP), increased mitochondrial proteins, decreased vesicular proteins and V-ATPase enzymes, and accumulation of various nucleosides were detected in lysosomes with TP deficiency. Treatment of cells with high concentrations of dThd and dUrd also triggers lysosomal dysfunction and disruption of mitochondrial homeostasis. Therefore, the results provided evidence that TP deficiency leads to nucleoside accumulation in lysosomes and lysosomal dysfunction, revealing the widespread disruption of organelles underlying MNGIE.
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DNA Mitocondrial , Fibroblastos , Lisossomos , Mitocôndrias , Encefalomiopatias Mitocondriais , Nucleosídeos , Timidina Fosforilase , Humanos , Lisossomos/metabolismo , Timidina Fosforilase/metabolismo , Timidina Fosforilase/deficiência , Timidina Fosforilase/genética , Encefalomiopatias Mitocondriais/metabolismo , Encefalomiopatias Mitocondriais/patologia , Encefalomiopatias Mitocondriais/genética , Fibroblastos/metabolismo , Fibroblastos/patologia , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , Nucleosídeos/metabolismo , Pseudo-Obstrução Intestinal/metabolismo , Pseudo-Obstrução Intestinal/patologia , Pseudo-Obstrução Intestinal/enzimologia , Pseudo-Obstrução Intestinal/genética , Oftalmoplegia/metabolismo , Oftalmoplegia/patologia , Oftalmoplegia/congênito , Distrofia Muscular Oculofaríngea/metabolismo , Distrofia Muscular Oculofaríngea/patologia , Masculino , Feminino , Pele/patologia , Pele/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/metabolismoRESUMO
AIM: Systemic amyloidosis is a condition in which misfolded amyloid fibrils are deposited within tissues. Amyloid myopathy is a rare manifestation of systemic amyloidosis. However, whether skeletal muscle involvement is underestimated and whether such deposition guarantees clinical and pathological myopathic features remain to be investigated. METHODS: We retrospectively reviewed patients with systemic amyloidosis, in whom skeletal muscle biopsies were performed at our centre between January 2018 and June 2023. In total, 28 patients with suspected systemic amyloidosis were included. Among these, 21 presented with cardiomyopathy but lacked myopathic symptoms. The clinical and pathological data of these patients were further analysed. The amyloid type was confirmed by immunohistochemistry. RESULTS: Twenty-eight patients with suspected systemic amyloidosis underwent muscle biopsy. Amyloid deposition in the skeletal muscle was confirmed in 24 patients, including 22 with light-chain amyloidosis (AL) and two with transthyretin amyloidosis (ATTR). Among the 24 patients, seven presented with muscle weakness and decreased muscle strength (Group 1, symptomatic myopathy), whereas the remaining 17 exhibited normal muscle strength (Group 2, asymptomatic myopathy). Group 1 included four patients with AL-λ, one with AL-κ and two with ATTR. Group 2 included 15 patients with AL-λ and two patients with AL-κ. In Group 1, six patients exhibited neuropathy, whereas only one patient in Group 2 presented with subclinical neuropathy on nerve conduction studies. Amyloid deposition in the interstitium was the most obvious change, observed in all 24 patients. Neuropathic changes, including denervation atrophy and muscle fibre grouping, were also common. Except for type 2 fibre atrophy, the other myopathic changes were mild and nonspecific. No sarcolemmal disruption was observed. Immunohistochemical analysis revealed marked positivity for MAC and MHC1 expression in the regions with amyloid deposits. Clinicopathological analysis revealed no significant differences in the extent of muscular amyloid deposition between the two groups. Nevertheless, patients in Group 1 displayed more pronounced neurogenic atrophy on skeletal muscle biopsies. CONCLUSIONS: Our study indicates that amyloid deposition in skeletal muscle is commonly observed but rarely causes symptomatic myopathy in systemic amyloidosis.
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Músculo Esquelético , Doenças Musculares , Humanos , Masculino , Músculo Esquelético/patologia , Músculo Esquelético/metabolismo , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Doenças Musculares/patologia , Doenças Musculares/metabolismo , Amiloidose/patologia , Amiloidose/complicações , Amiloidose/metabolismo , Amiloidose de Cadeia Leve de Imunoglobulina/patologia , Amiloidose de Cadeia Leve de Imunoglobulina/complicações , Amiloidose de Cadeia Leve de Imunoglobulina/metabolismo , Idoso de 80 Anos ou mais , Adulto , BiópsiaRESUMO
Hybrid metal halide materials with charming phase transition behaviors have attracted considerable attention. In former works, much attention has been focused on the phase transition triggered by the order-disorder or displacement motions of the organic component. However, manipulating the variation of the inorganic component to achieve the phase transition has rarely been reported. Herein, two novel organic-inorganic hybrid materials, [THPM]n[AgX2]n (THPM = 3,4,5,6-tetrahydropyrimidin-1-ium, X = I for 1 and Br for 2) with the [AgX2]nn- anionic chain structure, were synthesized. At 293 K, the [AgX2]nn- chains in 1 were constructed by the tetramer units of Ag atoms, while that in 2 was assembled by the dimer structure. Upon heating to 355 K, owing to the variation of the metallophilic interaction between adjacent Ag atoms, a unique transformation process from tetramer to dimer in [AgI2]nn- chains of 1 can be detected and endow 1 with a giant anisotropic thermal expansion with linear strain of â¼7% and shear strain of â¼20%, which can be used as a mechanical actuator for switching. Alternatively, for 2, no phase transition process can be observed upon the temperature variation. This work provides an effective approach to design phase transition materials triggered by the inorganic part.
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The construction of secondary building units (SBUs) in versatile metal-organic frameworks (MOFs) represents a promising method for developing multi-functional materials, especially for improving their sensitizing ability. Herein, we developed a dual small molecules auxiliary strategy to construct a high-nuclear transition-metal-based UiO-architecture Co16-MOF-BDC with visible-light-absorbing capacity. Remarkably, the N3 - molecule in hexadecameric cobalt azide SBU offers novel modification sites to precise bonding of strong visible-light-absorbing chromophores via click reaction. The resulting Bodipy@Co16-MOF-BDC exhibits extremely high performance for oxidative coupling benzylamine (~100 % yield) via both energy and electron transfer processes, which is much superior to that of Co16-MOF-BDC (31.5 %) and Carboxyl @Co16-MOF-BDC (37.5 %). Systematic investigations reveal that the advantages of Bodipy@Co16-MOF-BDC in dual light-absorbing channels, robust bonding between Bodipy/Co16 clusters and efficient electron-hole separation can greatly boost photosynthesis. This work provides an ideal molecular platform for synergy between photosensitizing MOFs and chromophores by constructing high-nuclear transition-metal-based SBUs with surface-modifiable small molecules.
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BACKGROUND: The aim of this study was to investigate whether postoperative adjuvant transcatheter arterial chemoembolization (TACE) treatment in wide- and narrow-margin groups could improve the long-term prognosis of patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A total of 670 patients with HCC who underwent radical hepatectomy from January 2016 to December 2017 were enrolled, including 397 patients and 273 patients in the wide- and narrow-margin groups. Recurrence-free survival (RFS) and overall survival (OS) outcomes were compared in the wide-margin and narrow-margin groups with and without adjuvant TACE postoperatively, respectively. Propensity score matching (PSM) analysis was used to match patients between TACE and no TACE groups in a 1:1 ratio. RESULTS: The wide-margin resection was associated with better RFS and OS rates than narrow-margin resection for patients with HCC. Patients with postoperative adjuvant TACE had a better RFS and OS than patients without postoperative adjuvant TACE in the narrow-margin group and reduced the intrahepatic recurrence rate (39.1% vs. 52.6%, P = .036) and the local recurrence rate in the liver (11.2% vs. 21.4%, P = .032). But postoperative adjuvant TACE did not alter recurrence and survival outcomes in the wide-margin group. Similar results were noted after propensity score matching (PSM). CONCLUSION: The wide-margin resection had better RFS and OS than the narrow-margin resection for patients with HCC. Postoperative adjuvant TACE was associated with reduced recurrence and improved OS after narrow-margin resection, but was not effective in the wide-margin resection.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Hepatectomia , Margens de Excisão , Quimioembolização Terapêutica/métodos , Estudos Retrospectivos , Prognóstico , Recidiva Local de Neoplasia/patologiaRESUMO
Constructing multiple functional geometric frustration magnets is a hot topic in solid state chemistry and material science. Herein, a two-dimensional (2D) parallel interpenetrating "star" net complex [HDMPDA][Fe6 (µ3 -O)2 (µ-O2 CH)15 ] (1) was obtained successfully with HDMPDA (DMPDA=N, N'-dimethyl-1,3-propanediamine) as charge balancer. The dipole reorientation of the rotator [HDMPDA]+ in the complex brings a structure transition which leads dielectric relaxation close to room temperature. Despite strong antiferromagnetic coupling existing between ions in the net, long-range order temperature TN of the complex is suppressed to 4.2â K by geometric frustration. Interestingly, below TN , a canted antiferromagnetic state, accompanied with slow magnetic relaxation, is detected due to the lack of enough magnetic coupling between 2D layers. Thus, 1 is a particular multifunctional magnetic frustration material containing two different types of relaxations.
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In this work, the single crystal to single crystal (SCSC) transformations in three mononuclear copper complexes [CuL22]Cl2·2H2O (1), [CuL12Cl2] (2), and [CuL22]Cl2·4H2O (3) (L1 = di-2-pyridyl ketone, L2 = di(pyridin-2-yl)methanediol) are realized by the irreversible dehydration and hydration reaction of L1 and L2. Dark purple crystal 1 is obtained by self-assembly of L1 and CuCl2·2H2O in solvothermal reactions, in which the carbonyl group of L1 undergoes a hydration addition reaction to form L2. On heating, 1 transforms to 2 by dehydrating water accompanied by the change of the color and coordination octahedron of CuII ions. In a saturated water vapor environment, 2 can absorb six water molecules and transform to 3 with the same color and coordination environment with 1 but different lattice water. The SCSC process from 2 to 3 is reversible: 3 can transform back to 2 on heating like that of 1. Chroma rewritable behaviors in the structural transformation of the complexes make them visually identifiable temperature or water probes.
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Novel 3D metal formate frameworks {[Ba4Cl][M3(HCO2)13]}n (M = Mn for 1, Co for 2, and Mg for 3) were successfully assembled via microwave-assisted synthesis. The complexes are rare coordination polymers crystallized at space group P4cc with the polar point group C4v. In the structure, the MII ions are bridged by two types of anti-anti formate in forming a 3D pcu framework, and additional formates coordinate to the unsaturated sites of the MII ions in the framework, giving an anionic M-formate net. Ba4Cl clusters take the cavities of the net as charge balance, in which the chloride ion deviates from the center of the barium ions. The asymmetric Ba4Cl structure is transmitted throughout the crystal resulting in polar structure, which is further confirmed by nonlinear optical and piezoelectric test. Nonlinear optical activity tests of 1 and 3 show SHG signals 0.32 and 0.28 times that of KDP, while 2 has a piezoelectric coefficient d33 of 6.8 pC/N along polar axis. Magnetic studies reveal antiferromagnetic coupling between MII ions in 1 and 2. Spin canting was found only in 2 with anisotropic CoII ions, and 2 is a canted antiferromagnetically with TN = 5 K. Further field-induced spin flop was also found in 2 with a critical field 0.9 T.
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Under solvothermal conditions, 10 molecular-ionic platinum compounds [Pt(NIA)2]·(L)·nH2O (L = dicarboxylate) were synthesized. In the reaction, acetonitrile undergoes trimerization in situ to generate N-(1-iminoethyl)acetamidine (NIA), which coordinates to PtII ions in forming the N-(1-iminoethyl)acetamidine platinum cation, while the organic carboxylates act as anions. Structural analysis shows that carboxylate ligands regulate the mode of packing of [Pt(NIA)2] in those compounds. Photoluminescence studies show that the photoluminescence behaviors of those compounds also depended on the carboxylate ligands. 1-4, 6, and 7 show blue light emission with fluorescence emission wavelengths of 437-440 nm despite the different carboxylate ligands used. 5 and 8 show green emissions with maximum intensity peak positions of 522 nm. Compared with that of 5 and 8, the emission of 9 and 10 has the same red shifts with peak positions of 567 and 528 nm. The variable-temperature photoluminescence studies reveal that 8 and 10 show two different thermal quenching (TQ) zones in the range of 80-420 K, while the emission intensity of 9 shows negative thermal quenching at low temperatures of 80-220 K and TQ in the range of 220-420 K.
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Distal myopathies are a group of clinically and genetically heterogeneous hereditary muscle disorders characterized by progressive muscular weakness starting in the distal parts of the limbs. The most common subtype of distal myopathy is GNE myopathy, a rare muscle disease with autosomal recessive inheritance. Limb-girdle muscular dystrophy 2G (LGMD2G) is a rare autosomal recessive subtype of LGMDs caused by TCAP variant. Patients with LGMD2G can present with distal myopathy and rimmed vacuoles on muscle pathology. Thus far, the most reported TCAP mutations related to LGMD2G were recessive frameshift or nonsense variants. Here, we described four Chinese patients from unrelated families with LGMD2G due to TCAP mutations. The clinical symptoms of our patients were similar to those previously reported in LGMD2G patients. Three different pathogenic TCAP variants were identified in these patients, including two frameshift variants and one intronic variant. Autophagolysosomes have been observed in one patient by electron microscopy. Our research expands the genetic spectrum of TCAP mutations in China, indicating c.165-166insG is likely the common pathogenic variant. We also provide evidences that autophagy may be involved in the pathophysiology of LGMD2G.
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Conectina/genética , Miopatias Distais/genética , Distrofia Muscular do Cíngulo dos Membros , Mutação/genética , Adulto , Povo Asiático , China , Miopatias Distais/diagnóstico , Miopatias Distais/patologia , Feminino , Humanos , Masculino , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/genética , Distrofia Muscular do Cíngulo dos Membros/patologia , LinhagemRESUMO
Proteasome inhibitors represent effective anti-tumor drugs. ONX0912 is a novel oral proteasome inhibitor that selectively targets the chymotrypsin-like activity of 20S proteasome subunits ß5 and LMP7 ï¼Low molecular mass polypeptide-7ï¼. It has been shown to be effective in hematologic malignancies. However, its anti-tumor effect in solid tumors remains unclear. Here, we discovered that ONX0912 suppressed the expansion of liver cancer cells. ONX0912 treatment led to an increased level of mitochondrial membrane potential collapse and mitochondrial ROS in tumor cells in a concentration- and exposure time-dependent manner, indicating ONX0912 triggers apoptosis through the intrinsic mitochondrial pathway. ONX0912 also induced mitophagy by activating Parkin/Pink pathway. Silencing mitophagy receptor protein, p62, aggravated the ONX0912-mediated apoptosis, which implied a new mechanism for the conversion between autophagy and apoptosis. Furthermore, we found that the ONX0912 target protein, LMP7 was overexpressed in liver cancer tissues compared to their adjacent tissues and increased level of LMP7 predicted worse clinical characteristics and poorer prognosis. In conclusion, we demonstrated that ONX0912 suppressed liver cancer cell expansion by inducing apoptosis and mitophagy. Our data also revealed ONX0912 as a potential clinical therapeutic drug for liver cancer therapy, and inhibition of mitophagy may sensitize the anti-tumor effect of ONX0912.
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Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Oligopeptídeos/farmacologia , Complexo de Endopeptidases do Proteassoma/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitofagia/efeitos dos fármacos , Estadiamento de Neoplasias , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Taxa de Sobrevida , Análise Serial de TecidosRESUMO
BACKGROUND: Circulating tumor cells (CTCs) with an epithelial-mesenchymal transition phenotype in peripheral blood may be a useful marker of carcinomas with poor prognosis. The aim of this study was to determine the prognostic significance of CTCs expressing Krüppel-like factor 8 (KLF8) and vimentin in pancreatic cancer (PC). METHODS: CTCs were isolated by immunomagnetic separation from the peripheral blood of 40 PC patients before undergoing surgical resection. Immunocytochemistry was performed to identify KLF8+ and vimentin+ CTCs. The associations between CTCs and time to recurrence (TTR), clinicopathologic factors, and survival were assessed. Univariate and multivariate analyzes were performed to identify risk factors. RESULTS: Patients with CTCs (n = 30) had a higher relapse rate compared to those without (n = 10) (70.0% vs 20.0%; P < 0.01). The proportion of KLF8+/vimentin+ CTCs to total CTCs was inversely related to TTR (r = -0.646; P < 0.01); TTR was reduced in patients with > 50% of CTCs identified as KLF8+/vimentin+ (P < 0.01). Independent risk factors for recurrence were perineural invasion and > 50% KLF8+/vimentin+ CTCs (both P < 0.05). CONCLUSION: Poor prognosis can be predicted in PC patients when > 50% of CTCs are positive for KLF8 and vimentin.
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Fatores de Transcrição Kruppel-Like/biossíntese , Células Neoplásicas Circulantes/metabolismo , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Vimentina/biossíntese , Adulto , Biomarcadores Tumorais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia , Prognóstico , Fatores de RiscoRESUMO
PURPOSE: Atherosclerosis, a chronic disease of the arteries, results from pathological processes including the accumulation and aggregation of oxidized low-density lipoprotein (oxLDL) in the vessel walls, development of neointima, formation of a fibrous cap, and migration of immune cells to damaged vascular endothelium. Recent studies have shown that mitochondrial dysfunction is closely associated with the development and progression of atherosclerosis. Idebenone, a short-chain benzoquinone similar in structure to coenzyme Q10, can effectively clear oxygen free radicals as an electron carrier and antioxidant. In the present study, we aim to investigate weather idebenone protects against atherosclerosis in apolipoprotein E-deficient (apoE-/-) mice. METHODS: apoE-/- mice receiving a high-fat diet (HFD) were treated with idebenone for 16 weeks. A total of 60 mice were randomized into the following four groups: (1) HFD, (2) HFD and low-dose idebenone (100 mg/kg/d), (3) HFD and medium-dose idebenone (200 mg/kg/d), and (4) HFD and high-dose (400 mg/kg/d). Proteomic analysis was performed between the HFD and idebenone-high-dose group. Plaque analysis was carried out by histological and immunohistochemical staining. Western blot, TUNEL staining, and MitoSOX assays were performed in human umbilical vein endothelial cells (HUVECs) to investigate the SIRT3-SOD2-mtROS pathway. RESULTS: Histological and morphological analysis demonstrated that idebenone significantly reduced plaque burden and plaque size. Idebenone treatment effectively stabilized the atherosclerotic plaques. In mice treated with idebenone, 351 up-regulated and 379 down-regulated proteins were found to be significantly altered in proteomic analysis. In particular, the expression of SIRT3, SOD2, and NLRP3 was significantly regulated in the idebenone treatment groups compared with the HFD group both in vivo and in vitro. We further confirmed that idebenone protected against endothelial cell damage and inhibited the production of mitochondrial reactive oxygen species (mtROS) in cholesterol-treated HUVECs. CONCLUSIONS: We demonstrated that idebenone acted as a mitochondrial protective agent by inhibiting the activation of NLPR3 via the SIRT3-SOD2-mtROS pathway. Idebenone may be a promising therapy for patients with atherosclerosis by improving mitochondrial dysfunction and inhibiting oxidative stress.
Assuntos
Aterosclerose/fisiopatologia , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 3/efeitos dos fármacos , Superóxido Dismutase/efeitos dos fármacos , Ubiquinona/análogos & derivados , Animais , Apolipoproteínas E , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Proteômica , Distribuição Aleatória , Ubiquinona/farmacologia , Imagens com Corantes Sensíveis à VoltagemRESUMO
BACKGROUND: Mitochondrial disorders are clinically heterogeneous diseases associated with impaired oxidative phosphorylation (OXPHOS) activity. POLG, which encodes the DNA polymerase-γ (Polγ) catalytic subunit, is the most commonly mutated nuclear gene associated with mitochondrial disorders. METHODS: We carried out whole-exome sequencing (WES) to identify the gene associated with progressive external ophthalmoplegia (PEO). We then performed histopathological analyses, assessed mitochondrial biology, and executed functional studies to evaluate the potential pathogenicity of the identified genetic mutations. RESULTS: Novel biallelic POLG mutations, including a large deletion mutation (exons 7-21) and a missense variant c.1796C>T (p.Thr599Ile) were detected in the proband. Histopathological analysis of a biopsied muscle sample from this patient revealed the presence of approximately 20% COX-negative fibers. Bioinformatics analyses confirmed that the detected mutations were pathogenic. Furthermore, levels of mitochondrial complex I, II, and IV subunit protein expressions were found to be decreased in the proband, and marked impairment of mitochondrial respiration was evident in cells harboring these mutations. CONCLUSION: This study expands the spectrum of known POLG variants associated with PEO and advances current understanding regarding the structural and functional impacts of these mutations.
Assuntos
DNA Polimerase Dirigida por DNA , Oftalmoplegia Externa Progressiva Crônica , DNA Polimerase gama/genética , DNA Mitocondrial/genética , DNA Polimerase Dirigida por DNA/genética , Humanos , Mutação/genética , Mutação de Sentido Incorreto , Oftalmoplegia Externa Progressiva Crônica/genéticaRESUMO
Community detection is challenging when the network structure is estimated with uncertainty. Dynamic networks present additional challenges but also add information across time periods. We propose a global community detection method, persistent communities by eigenvector smoothing (PisCES), that combines information across a series of networks, longitudinally, to strengthen the inference for each period. Our method is derived from evolutionary spectral clustering and degree correction methods. Data-driven solutions to the problem of tuning parameter selection are provided. In simulations we find that PisCES performs better than competing methods designed for a low signal-to-noise ratio. Recently obtained gene expression data from rhesus monkey brains provide samples from finely partitioned brain regions over a broad time span including pre- and postnatal periods. Of interest is how gene communities develop over space and time; however, once the data are divided into homogeneous spatial and temporal periods, sample sizes are very small, making inference quite challenging. Applying PisCES to medial prefrontal cortex in monkey rhesus brains from near conception to adulthood reveals dense communities that persist, merge, and diverge over time and others that are loosely organized and short lived, illustrating how dynamic community detection can yield interesting insights into processes such as brain development.