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Circular RNAs (circRNAs) are unique noncoding RNAs that have a closed and stable loop structure generated through backsplicing. Due to their conservation, stability and tissue specificity, circRNAs can potentially be used as diagnostic indicators and therapeutic targets for certain tumors. Many studies have shown that circRNAs can act as microRNA (miRNA) sponges, and engage in interactions with proteins and translation templates to regulate gene expression and signal transduction, thereby participating in the occurrence and development of a variety of malignant tumors. Immunotherapy has revolutionized the treatment of cancer. Early researches have indicated that circRNAs are involved in regulating tumor immune microenvironment and antitumor immunity. CircRNAs may have the potential to be important targets for increasing sensitivity to immunotherapy and expanding the population of patients who benefit from cancer immunotherapy. However, few studies have investigated the correlation between circRNAs and tumor immunity. In this review, we summarize the current researches on circRNAs involved in antitumor immune regulation through different mechanisms and their potential value in increasing immunotherapy efficacy with the goal of providing new targets for cancer immunotherapy.
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Imunoterapia , Neoplasias , RNA Circular , Microambiente Tumoral , RNA Circular/genética , Humanos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/imunologia , Imunoterapia/métodos , Animais , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , MicroRNAs/genéticaRESUMO
The blood-brain barrier (BBB) and drug resistance present challenges for chemotherapy of glioblastoma (GBM). A microneedle (MN) patch with excellent biocompatibility and biodegradability was designed to bypass the BBB and release temozolomide (TMZ) and PLCG1-siRNA directly into the tumor site for synergistic treatment of GBM. The codelivery of TMZ and PLCG1-siRNA enhanced DNA damage and apoptosis. The potential mechanism behind this enhancement is to knockdown of PLCG1 expression, which positively regulates the expression of signal transducer and activator of transcription 3 genes, thereby preventing DNA repair and enhancing the sensitivity of GBM to TMZ. The MN patch enables long-term sustainable drug release through in situ implantation and increases local drug concentrations in diseased areas, significantly extending mouse survival time compared to other drug treatment groups. MN drug delivery provides a platform for the combination treatment of GBM and other central nervous system diseases.
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Neoplasias Encefálicas , Glioblastoma , Animais , Camundongos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , RNA Interferente Pequeno/genética , Resistencia a Medicamentos Antineoplásicos/genética , Terapia Combinada , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Bioactive peptides are specific peptide which usually contains 2-20 amino acid residues and actively exerts various functions and biological activities and ultimately affect health. Programmed cell deaths are some styles of cell death discovered in recent years, which is the key to tissue development and balance, eliminating excess, damaged or aging cells. More importantly, programmed cell death is a potential way to treat inflammatory diseases and cancer. In this review, through screening references from 2015 to present, we introduce the effect of bioactive peptides derived from food proteins on inflammatory diseases or cancer through regulating programmed cell deaths, including apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis. And this review also introduces the targets of these bioactive peptides to regulate programmed cell death. The purpose of this review is to help to expand the prospective applications of bioactive peptides in the field of inflammatory disease and cancer to provide some guidance.
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Apoptose , Neoplasias , Humanos , Morte Celular , Piroptose , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Neoplasias/tratamento farmacológicoRESUMO
Gliomas are the most common and recalcitrant intracranial tumors, approximately a quarter of which are classified as lower-grade gliomas (WHO II-III). Although the prognosis of lower-grade gliomas (LGGs) is significantly better than that of higher-grade gliomas, as a highly heterogeneous tumor type, the prognosis of LGGs varies greatly based on the molecular diagnosis. IDH wild-type used to be regarded as a dismal prognostic biomarker in LGGs; however, several studies revealed that IDH wild-type LGGs might not always be equivalent to glioblastoma (WHO IV). Hence, we hypothesize that underlying biological events in LGGs can result in different prognosis. In our study, transcriptome profiling was performed in 24 samples of LGG, and the results showed that the expression of phospholipase Cγ1 (PLCG1) was significantly correlated with IDH1/2 status and patients' clinical outcome. Furthermore, the cancer genome atlas (TCGA) and the Chinese glioma genome atlas (CGGA) databases verified that elevated PLCG1 expression was associated with tumor progression and poor survival in LGG patients. Moreover, PLCG1-targeted siRNA dramatically affected the growth, migration and invasiveness of IDH wild-type LGG cell lines. In in vitro and in vivo experiments, the PLC-targeted drug significantly suppressed the tumor growth of IDH wild-type LGG cell lines in vitro and tumors in mouse models. Taken together, our results demonstrated that higher PLCG1 expression was associated with tumor growth and worse prognosis in IDH wild-type LGGs and PLCG1 could serve as a potential therapeutic target for IDH wild-type LGG patients.
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Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Isocitrato Desidrogenase/genética , Fosfolipase C gama/genética , Adulto , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Perfilação da Expressão Gênica , Glioma/metabolismo , Glioma/patologia , Humanos , Isocitrato Desidrogenase/metabolismo , Estimativa de Kaplan-Meier , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Gradação de Tumores , Fosfolipase C gama/metabolismo , Interferência de RNA , Transplante HeterólogoRESUMO
Excessive reactive oxygen species (ROS), a highly reactive substance that contains oxygen, induced by ultraviolet A (UVA) cause oxidative damage to skin. We confirmed that hemin can catalyze the reaction of tyrosine (Tyr) and hydrogen peroxide (H2O2). Catalysis was found to effectively reduce or eliminate oxidative damage to cells induced by H2O2 or UVA. The scavenging effects of hemin for other free-radical ROS were also evaluated through pyrogallol autoxidation, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·)-scavenging assays, and phenanthroline-Fe2+ assays. The results show that a mixture of hemin and tyrosine exhibits strong scavenging activities for H2O2, superoxide anion (O2-·), DPPH·, and the hydroxyl radical (·OH). Furthermore, the inhibition of oxidative damage to human skin keratinocyte (HaCaT) cells induced by H2O2 or UVA was evaluated. The results show that catalysis can significantly reduce the ratio of cell apoptosis and death and inhibit the release of lactate dehydrogenase (LDH), as well as accumulation of malondialdehyde (MDA). Furthermore, the resistance to apoptosis was found to be enhanced. These results show that the mixture of hemin and tyrosine has a significantly protective effect against oxidative damage to HaCaT cells caused by UVA, suggesting it as a protective agent for combating UVA damage.
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BACKGROUND: There is increasing evidence that blood oxygenation level-dependent signaling in white matter (WM) reflects WM functional activity. Whether this activity is altered in schizophrenia remains uncertain, as does whether it is related to established alterations of gray matter (GM) or the microstructure of WM tracts. METHODS: A total of 153 antipsychotic-naïve schizophrenia patients and 153 healthy comparison subjects were assessed by resting-state functional magnetic resonance imaging, diffusion tensor imaging, and high-resolution T1-weighted imaging. We tested for case-control differences in the functional activity of WM, and examined their relation to the functional activity of GM and WM microstructure. The relations between fractional anisotropy (FA) in WM and GM-WM functional synchrony were investigated as well. Then, we examined the associations of identified abnormalities to age, duration of untreated psychosis (DUP), and symptom severity. RESULTS: Schizophrenia patients displayed reductions of the amplitude of low-frequency fluctuations (ALFF), GM-WM functional synchrony, and FA in widespread regions. Specifically, the genu of corpus callosum not only had weakening in the synchrony of functional activity but also had reduced ALFF and FA. Positive associations were found between FA and functional synchrony in the genu of corpus callosum as well. No significant association was found between identified abnormalities and DUP, and symptom severity. CONCLUSIONS: The widespread weakening in the synchrony of functional activity of GM and WM provided novel evidence for functional alterations in schizophrenia. Regarding the WM function as a component of brain systems and investigating its alternation represent a promising direction for future research.
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Esquizofrenia , Substância Branca , Humanos , Substância Branca/patologia , Imagem de Tensor de Difusão/métodos , Encéfalo , Substância Cinzenta/patologia , Anisotropia , Imageamento por Ressonância Magnética/métodosRESUMO
The experimentally known reaction of Cp2Cr2(CO)6 with white phosphorus (P4) to give CpCr(CO)2(η3-P3), Cp2Cr2(CO)4(µ-η,2η2-P2), and the triple-decker sandwich Cp2Cr2(µ-η,5η5-P5) is of interest since the P4 reactant having a tetrahedral cluster of four phosphorus atoms is converted to products having P2, P3, and P5 ligands. The mechanism of this obviously complicated reaction can be dissected into three stages using a coupled cluster theoretical method that has been benchmarked with the P2, Mn(CO)5, and CpCr(CO)3 dimerization processes. The first stage of the Cp2Cr2(CO)6/P4 reaction mechanism generates the unsaturated singlet intermediate Cp2Cr2(CO)5 that combines with the P4 reactant. Decarbonylation of the resulting Cp2Cr2(CO)5(P4) complex provides a singlet tetracarbonyl readily fragmenting into the stable triphosphacyclopropenyl complex CpCr(CO)2(η3-P3) and the chromium phosphide CpCr(CO)2(P). The isomeric triplet tetracarbonyl Cp2Cr2(CO)4(P4), readily fragments into CpCr(CO)2(η2-P2), which can generate the stable diphosphaacetylene complex Cp2Cr2(CO)4(η,2η2-P2) as well as the pentamer [CpCr(CO)2]5(P10). Combination of the coordinately unsaturated CpCr(CO)(η3-P3) with CpCr(CO)2(η2-P2) can lead to a ring expansion. This generates the P5 pentagonal ligand in a Cp2Cr2(CO)3(P5) precursor to the experimentally observed carbonyl-free triple-decker sandwich Cp2Cr2(µ-η,5η5-P5) after three successive decarbonylations.
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On the basis of an undeveloped asymmetrical pyridylcarboxylate ligand, 2-(2-carboxypyridin-4-yl)terephthalic acid (H3CPTA), an indium pyridylcarboxylate framework, [(Me)2NH2]1.5[In1.5(CPTA)2]·5.5NMF·6H2O (1), is synthesized under solvent thermal conditions. 1 displays a 3D anionic framework with a large void space, which contains open square channels with a cross section of 14.6 Å and a pore surface decorated with carboxylic oxygen atoms. Depending on the anionic skeleton and high water stability, 1 exhibits high adsorption selectivity and capacity for cationic dyes in aqueous solution. Furthermore, the luminescence performance illustrates that 1 has selectivity and sensitivity to nitenpyram with good recyclability.
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OBJECTIVE: To compare the safety, reintervention and pregnancy outcomes between ultrasound-guided high intensity focused ultrasound (USgHIFU) and hysteroscopic myomectomy (HM) for submucosal fibroids. MATERIALS AND METHODS: A total of 215 patients with a solitary submucosal fibroid treated by USgHIFU or HM at the third Xiangya Hospital were retrospectively reviewed. Among them, 58 treated with USgHIFU, 157 treated with HM. RESULTS: A significant difference was observed in size, location and type of the fibroids, effective rate, and cumulative reintervention rate between the two groups (p < .05). The size of the fibroids was 57.9 ± 1.9 mm in the USgHIFU group, while it was 32.6 ± 1.2 mm in the HM group. The number of the fibroids at horn or fundus/uterine cavity was 16/42 in the USgHIFU group, while it was 21/136 in the HM group. The number of type I/II/2-5 was 16/17/25 in the USgHIFU group, while it was 133/24/0 in the HM group. In the USgHIFU group, the effective rate was 100% and the cumulative reintervention rate at 50 (17-97) months was 19.0%, while in the HM group, it was 94.3% and 7.6%, respectively. During the follow-up period, the pregnancy rate was 22.4% (13/58) and the reintervention rate due to invalid and recurrence was 15.5% (9/58) in the USgHIFU group, while they were 18.5% (29/157) and 7.0% (11/157) in the HM group. No significant difference was observed between the two groups (p > .05). Furthermore, the reintervention rate was positively correlated with age, treatment methods and parity and fertility requirements. No other significant difference was observed between the two groups. CONCLUSIONS: Both USgHIFU and HM are safe and effective in treating submucosal fibroids. Compared with the HM group, the USgHIFU group had lower postoperative complications, but higher reintervention rate, with similar recurrence rate, pregnancy rate and reintervention rate due to invalid and recurrence. Reintervention was related to age, treatment methods, parity and fertility requirements.
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Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Miomectomia Uterina , Neoplasias Uterinas , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/cirurgia , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgiaRESUMO
Oxidative damage caused by the ferryl hemoglobin is one of the major clinical adverse reactions of hemoglobin-based oxygen carriers (HBOCs), while the production of reactive oxygen species in a pathological state can oxidize hemoglobin (HbFe2+ ) to ferryl Hb, which can then enter the pseudoperoxidase cycle, making hemoglobin highly toxic. In this study, we found that ferrous hemoglobin and polymerized porcine hemoglobin (one of the HBOCs) have the peroxidase activity different from the pseudoperoxidase activity of ferric hemoglobin. Ferrous hemoglobin can catalyze the reaction of tyrosine (Tyr) with hydrogen peroxide. In addition, the results also indicated that ferrous hemoglobin and pPolyHb have a strong inhibitory effect on the pseudoperoxidase activity of ferric hemoglobin. Therefore, hydrogen peroxide was consumed in a large amount, which greatly prevented hemoglobin from becoming oxidized and entering the pseudoperoxidase cycle, thus inhibiting ferryl Hb toxicity. We further cultured human umbilical vein endothelial cells and monitored cell morphology, viability, cell cycle, apoptosis, lactate dehydrogenase (LDH) release, and malondialdehydes (MDAs) formation when incubated with H2 O2 , Tyr, and HbFe2+ . HbFe2+ and pPolyHb reduced cell cycle arrest, apoptosis, LDH release, and MDA formation. These results showed that reducing oxidative damage induced by H2 O2 and converted hemoglobin from a molecule that is toxic to one that inhibits oxidative damage, suggesting a new strategy for development of a safer HBOCs.
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Substitutos Sanguíneos/química , Substitutos Sanguíneos/farmacologia , Hemoglobinas/farmacologia , Peróxido de Hidrogênio/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Hemoglobinas/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Peroxidases/química , SuínosRESUMO
BACKGROUND: Schizophrenia is one of the most severe psychiatric disorders and dysfunction of gray matter (GM) has been usually investigated by resting-state functional (f)MRI. However, functional organization of white matter (WM) in chronic schizophrenia remains unclear. PURPOSE: To investigate the WM functional alterations in chronic never-treated schizophrenia and the effects of long-term antipsychotic treatment. STUDY TYPE: Prospective. SUBJECTS: Twenty-five never-treated, 41 matched antipsychotic-treated schizophrenia, and 25 healthy comparison subjects. FIELD STRENGTH/SEQUENCE: Resting state (rs)-fMRI, T1 -weighted images (T1 WI), and diffusion tensor imaging (DTI) covering the whole brain were acquired with a 3.0T scanner. ASSESSMENT: Amplitude of low-frequency fluctuations (ALFF) in WM and the correlation coefficients between WM and GM were examined and compared among the three participant groups by two reviewers independently. Independent component analysis (ICA) was added to evaluate WM-fMRI signals. Statistical Tests: Analysis of covariance (ANCOVA); Pearson correlation analysis. RESULTS: Never-treated patients demonstrated lower ALFF in splenium of corpus callosum (SCC) relative to treated patients and controls (P < 0.001, false discovery rate [FDR]-corrected). While the extracted independent component also located in SCC and showed significantly decreased connectivity in never-treated patients when compared to controls (P < 0.05, FDR-corrected). The correlation coefficients of WM-GM displayed greater reductions in the genu of corpus callosum (GCC), pontine crossing tract (PC), bilateral cingulum (hippocampus) (CGH), and bilateral corticospinal tract (CST) in treated patients relative to controls (P < 0.05, FDR-corrected). DATA CONCLUSION: These findings provide new insight into WM functional alterations over the long-term course of schizophrenia with and without the potential effects of antipsychotic medication. Functional change and abnormal connectivity in SCC were both found greater in untreated patients than treated patients relative to healthy controls, suggesting that long-term antipsychotic treatment may show some protective effects on WM functional organization. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;52:752-763.
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Esquizofrenia , Substância Branca , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Estudos Prospectivos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Substância Branca/diagnóstico por imagemRESUMO
The singlet-triplet energy splittings (STES) of dication carbon chains capped by three 16-electron and two 14-electron configuration transition metal termini have been investigated using density functional theory. All five transition metal-capped carbon chains (MCC) exhibit an odd-even STES alternation, suggesting that it is a general feature of the MCCs. Analysis of the frontier molecular orbitals indicates that the frontier and neighboring molecular orbitals (MOs) are π orbitals delocalized over the entire carbon chain, the transition metal termini, and the ancillary ligands. In even and odd metal-carbon chains the HOMOs and LUMOs are nearly degenerate and non-degenerate, respectively, resulting in the even-odd STES alternation. Further analysis of the MOs in the MCCs and the uncapped carbon chains indicate that the STES of the MCCs are determined substantially by the uncapped carbon chain. Other ancillary ligands also play important roles in tuning the energy splitting through their π donor and acceptor abilities. These observations are helpful for the design of cumulene materials exhibiting tunable electronic and optical properties.
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BACKGROUND: Gallstone disease (GSD) is a common biliary tract disease worldwide. Previous studies have investigated the association of apolipoprotein E (APOE) E4 with GSD and reported inconsistent results. METHODS: In this paper, we conducted meta-analyses to examine whether APOE E4 is associated with the risk of GSD. A systematic literature search was performed in PubMed, Cochrane Library, EMBASE, and Google Scholar using the following inclusion criteria: 1) Studies on human subjects; 2) subjects in the control group must undergo ultrasound GSD screening, and presence of GSD in the experiment group can be clearly determined, e.g., diagnosis of GSD through ultrasound screening or a previous history of cholecystectomy or cholelithiasis; 3) the studies reported APOE genotype data (APOE E4+ vs. E4-) for subjects with and without GSD. In all the meta-analyses, we used random-effects models to calculate the odds ratios (ORs) as a measure of association as well as the corresponding confidence intervals (CIs). RESULTS: Our literature search found 13 publications with 14 studies, including a total of 1632 GSD patients and 5001 controls, that met the eligibility criteria and were included in the meta-analyses. We did not find a significant association between APOE E4 and risk of GSD (OR = 1.23, 95% CI: 0.89-1.68; p = 0.205). No significant associations were observed in subgroup analyses by gender and mean age. We obtained similar insignificant findings if an additive model was used, if subjects who had E2E4 genotype were excluded, or if low-quality studies were excluded. CONCLUSION: Our meta-analysis found insufficient evidence for the effect of APOE E4 on GSD risk. Future studies with large sample sizes that control for important confounding/risk factors are needed to validate our findings and to explore other genetic loci that might affect GSD risk.
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Apolipoproteínas E/genética , Cálculos Biliares/genética , Estudos de Associação Genética , Apolipoproteínas E/metabolismo , Bases de Dados Factuais , Predisposição Genética para Doença , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de RiscoRESUMO
Proliferation of vascular smooth muscle cells (VSMCs) plays an important role in various vascular diseases. Abnormal hemodynamic factors are important stimulus for promoting proliferation of VSMCs. In this study, we show that transmural pressure (TP) promotes the proliferation of human arterial smooth muscle cells (HASMCs) and its related mechanism. HASMCs were treated with different TPs (0,100,120,140,160,180 and 200â¯mmHg) in a custom-made pressure loading apparatus for 6â¯h. Results showed that proliferation of HASMCs was significantly promoted when the TP was over 160â¯mmHg compared with 0â¯mmHg (atmosphere pressure). In like manner, the expressions of NADPH oxidase 2(Nox2) and Survivin (SVV) and production of intracellular reactive oxygen species (ROS) were all elevated distinctly when TP exceeded 160â¯mmHg. Moreover, ROS scavenger NAC reduced TP-induced proliferation of HASMCs and expression of SVV largely, and slightly down-regulated expression of NOX2. NOX inhibitor apocynin (Apo) also significantly reduced TP-induced proliferation of HASMCs and expression of SVV and almost completely eliminated TP-induced production of ROS. These results demonstrate that TP drives proliferation of HASMCs via mechanism associated with NOX and SVV.
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Pressão Arterial , Proliferação de Células , Mecanotransdução Celular , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , NADPH Oxidase 2/metabolismo , Survivina/metabolismo , Células Cultivadas , Humanos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Aneuploidy of chromosome 8 in circulating tumor cells (CTCs) has been reported correlates with therapeutic efficacy and prognosis in patients with advanced gastric cancer. However, it is not clear whether it is also appropriate for other cancer. Therefore, in this study, we evaluate the clinical application aneuploidy of CTCs for esophageal cancer. METHODS: Peripheral blood were collected for karyotyping analysis before and after first 4-cycles chemotherapy from seventy nine patients with newly diagnosed esophageal cancer. Karyotyping of chromosome 8 in CTCs detected by SET-iFISH (Subtraction Enrichment-Immunostaining fluorescence in situ hybridizatio) in those patients were grouped into two categories according to CTC number: triploid group and non-triploid group. Pearson Chi-Square were used to compare the association between different aneuploidy type and chemotherapeutic sensitivity and efficacy. RESULTS: Among the 16 patients with triploid of chromosome 8, 4 patients benefit, and of the 63 patients with non-triploid, 54 patients benefit. Chi-square test analysis found that clinical benefit of non-triploid patients was significantly higher than triploid patients, suggesting non-triploid patients were more sensitive to chemotherapy than triploid patients. After 4-cycles chemotherapy, it is found that chemotherapeutic efficacy was positively correlated with non-triploid proportion. These results suggest that non-triploid proportion could be used as a candidate maker for assessing chemotherapeutic efficacy. CONCLUSIONS: Monitoring aneuploidy of chromosome 8 in CTCs before and after chemotherapy may help predict sensitivity and efficacy of chemotherapy in patients with esophageal cancer.
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Aneuploidia , Cromossomos Humanos Par 8 , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Cariotipagem , Células Neoplásicas Circulantes , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/patologia , Humanos , Hibridização in Situ Fluorescente/métodos , Técnicas de Hibridização Subtrativa , Resultado do Tratamento , TriploidiaRESUMO
BACKGROUND: White matter (WM) blood oxygenation level-dependent (BOLD) signals are reported to be related to neural activity. However, sensitivity of WM BOLD signals to disease remains unclear. PURPOSE: To investigate WM BOLD signal changes, directional variations of resting-state correlations in sensorimotor system in patients with pontine strokes, and to determine the relationship between WM BOLD signals and motor deficits. STUDY TYPE: Prospective. SUBJECTS: Ethical approval was obtained from the local Ethics Committee and each participant gave written informed consent. Sixteen patients with focal pontine lesions and 16 age-matched control subjects were included. FIELD STRENGTH/SEQUENCE: 3.0T T1 -weighted anatomic images using a 3D magnetization-prepared rapid gradient-echo sequence. Resting-state fMRI images using gradient-echo echo-planar imaging sequence. Diffusion-weighted images using single-shot spin-echo diffusion echo-planar imaging. ASSESSMENT: Relevant WM tracts in the sensorimotor system by region of interest-wise analysis were identified. Power spectra of BOLD signals and anisotropy of resting-state correlations were measured in sensorimotor system and compared between two groups. Their relationships with clinical scores were analyzed. STATISTICAL TESTS: Two-sample t-test; partial correlation analysis. RESULTS: Power spectra of BOLD signals in nerve tracts on the ipsilesional side were significantly decreased (P < 0.05). Compared with that in healthy subjects, the anisotropy of resting-state correlations along identified WM tracts was decreased in the thalamus-dorsolateral prefrontal cortex bundle on the contralesional side, and all nerve tracts on the ipsilesional side. Partial least squares regression analysis showed the predicted outcome scores correlated significantly with actual Fugl-Meyer scores (R2 = 0.944, P = 0.013). DATA CONCLUSION: Our findings suggest that disrupted activity and functional connectivity in WM areas of the sensorimotor system can be detected in pontine strokes, and may serve as a biomarker for motor function prediction. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:478-486.
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Imageamento por Ressonância Magnética , Ponte/diagnóstico por imagem , Córtex Sensório-Motor/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Idoso , Anisotropia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Estudos ProspectivosRESUMO
Our bioassays reviewed that antennae played crucial roles in the responses of maize weevil (Sitophilus zeamais) to food and sex volatiles. In order to identify the maize weevil odorant-binding protein (OBP) genes, we analyzed its antennal transcriptome. In total, 21,587,928 high-quality clean reads were obtained from RNA-seq, 52,206 unigenes were assembled, and 25,744 unigenes showed significant similarity ( E value < 10 -5 ) to known proteins in the NCBI nonredundant protein database. From those unigenes, we identified 41 candidate OBP proteins, which could be categorized into dimeric OBPs subfamily, minus-C OBPs subfamily, and classical OBPs subfamily. Phylogenic analysis indicated that most maize weevil OBPs were closely related to their orthologues in other beetles of the Superfamily Curculionoidea. We further investigated the expression profiles of those candidate OBP genes by quantitative real-time polymerase chain reaction. Twenty-six of forty-one maize weevil OBP genes were highly expressed in the antennae or other parts of the head. The rest were expressed in the legs, wings, or other tested tissues. The antennal transcriptomic data and candidate OBP genes described here provide a basis for the functional studies of the maize weevil chemical perception, which are potential novel targets for pest control strategies.
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Antenas de Artrópodes/metabolismo , Perfilação da Expressão Gênica , Receptores Odorantes/genética , Gorgulhos/genética , Animais , Expressão Gênica , Proteínas de Insetos/genética , Filogenia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Receptores Odorantes/metabolismo , Gorgulhos/metabolismoRESUMO
Functional MRI has proven to be effective in detecting neural activity in brain cortices on the basis of blood oxygenation level dependent (BOLD) contrast, but has relatively poor sensitivity for detecting neural activity in white matter. To demonstrate that BOLD signals in white matter are detectable and contain information on neural activity, we stimulated the somatosensory system and examined distributions of BOLD signals in related white matter pathways. The temporal correlation profiles and frequency contents of BOLD signals were compared between stimulation and resting conditions, and between relevant white matter fibers and background regions, as well as between left and right side stimulations. Quantitative analyses show that, overall, MR signals from white matter fiber bundles in the somatosensory system exhibited significantly greater temporal correlations with the primary sensory cortex and greater signal power during tactile stimulations than in a resting state, and were stronger than corresponding measurements for background white matter both during stimulations and in a resting state. The temporal correlation and signal power under stimulation were found to be twice those observed from the same bundle in a resting state, and bore clear relations with the side of stimuli. These indicate that BOLD signals in white matter fibers encode neural activity related to their functional roles connecting cortical volumes, which are detectable with appropriate methods.
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Mapeamento Encefálico , Córtex Somatossensorial/fisiologia , Percepção do Tato/fisiologia , Substância Branca/fisiologia , Adulto , Imagem de Tensor de Difusão , Imagem Ecoplanar , Feminino , Humanos , Masculino , Estimulação Física , Tato , Adulto JovemRESUMO
A novel and sensitive nonenzymatic sandwich-type electrochemical immunosensor was developed for the detection of C-reactive protein. The catalytic activity of Ag/Pt nanomaterials that possessed an intrinsic enzyme catalytic activity similar to that of horseradish peroxidase (HRP) was utilized as a label to improve the stability and sensitivity using amino graphene as an immobilization matrix. Comparing with the common methods of using HRP as labels for electrochemical detection, Ag/Pt nanoparticles might have longer lifetime than that of enzymes. As far as know, there is no other report using Ag/Pt as catalytic labels for electrocatalyzed reduction of H2O2 to fabricate the amperometric immunosensor. Under the optimized experimental conditions, the detection range of the sensor is from 0.5 ng/mL to 140 ng/mL with a linear correlation coefficient of 0.9934 and the detection limit of 0.17 ng/mL at 3σ . The sensor has good stability, reproducibility and high sensitivity. Therefore, the immunosensor is promising for applications in point-of-care diagnostics.
Assuntos
Proteína C-Reativa/análise , Grafite/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Platina/química , Prata/química , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Denoising is the primary preprocessing step for subsequent application of MRI. However, most commonly-used patch-based denoising methods are heavily dependent on the degree of patch matching. Due to the large number of voxels in the 3D MRI dataset, the procedure of searching sufficient similarity patches was limited by the empirical compromising between computational efficiency and estimation accuracy, and cannot fulfill the application in multimodal MRI dataset with different SNR and resolutions. METHODS: In this study, we propose a modified global filtering framework for 3D MRI. For each denoising voxel, the similarity weighting matrix is computed using the reference patch and other patches from the whole dataset. This large weighting matrix is then approximated using the k-means clustering Nyström method to achieve computational viability. RESULTS: Experiments on both synthetic and in vivo MRI datasets demonstrated that the proposed adaptive Nyström low-rank approximation could achieve competitive estimation compared with exact global filter while reducing the sampling rate by four orders of magnitude. In addition, the corresponding global filter improved patches-based method in both spatial and transform domain. CONCLUSION: We propose a global denoising framework for 3D MRI which extracts information from the entire dataset to restore each voxel. This large weighting matrix of the global filter is approximated using Nyström low-rank approximation with an adaptive k-means clustering sampling scheme, which significantly reduce the sampling rate as well as the running time. The proposed method is capable of denoising in multimodal MRI dataset and can be used to improve currently used patch-based methods.