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1.
Stem Cells ; 42(6): 567-579, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38469899

RESUMO

Wnt/ß-catenin signaling plays a crucial role in the migration of mesenchymal stem cells (MSCs). However, our study has revealed an intriguing phenomenon where Dickkopf-1 (DKK1), an inhibitor of Wnt/ß-catenin signaling, promotes MSC migration at certain concentrations ranging from 25 to 100 ng/mL while inhibiting Wnt3a-induced MSC migration at a higher concentration (400 ng/mL). Interestingly, DKK1 consistently inhibited Wnt3a-induced phosphorylation of LRP6 at all concentrations. We further identified cytoskeleton-associated protein 4 (CKAP4), another DKK1 receptor, to be localized on the cell membrane of MSCs. Overexpressing the CRD2 deletion mutant of DKK1 (ΔCRD2), which selectively binds to CKAP4, promoted the accumulation of active ß-catenin (ABC), the phosphorylation of AKT (Ser473) and the migration of MSCs, suggesting that DKK1 may activate Wnt/ß-catenin signaling via the CKAP4/PI3K/AKT cascade. We also investigated the effect of the CKAP4 intracellular domain mutant (CKAP4-P/A) that failed to activate the PI3K/AKT pathway and found that CKAP4-P/A suppressed DKK1 (100 ng/mL)-induced AKT activation, ABC accumulation, and MSC migration. Moreover, CKAP4-P/A significantly weakened the inhibitory effects of DKK1 (400 ng/mL) on Wnt3a-induced MSC migration and Wnt/ß-catenin signaling. Based on these findings, we propose that DKK1 may activate the PI3K/AKT pathway via CKAP4 to balance the inhibitory effect on Wnt/ß-catenin signaling and thus regulate Wnt3a-induced migration of MSCs. Our study reveals a previously unrecognized role of DKK1 in regulating MSC migration, highlighting the importance of CKAP4 and PI3K/AKT pathways in this process.


Assuntos
Movimento Celular , Peptídeos e Proteínas de Sinalização Intercelular , Células-Tronco Mesenquimais , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Via de Sinalização Wnt , Proteína Wnt3A , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco Mesenquimais/metabolismo , Movimento Celular/efeitos dos fármacos , Proteína Wnt3A/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Humanos , Animais , beta Catenina/metabolismo , Fosforilação/efeitos dos fármacos , Camundongos , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética
2.
Small ; 20(23): e2308145, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150646

RESUMO

Carbon fiber composites have great application prospects as a potential electromagnetic (EM) wave-absorbing material, yet it remains extremely challenging to integrate multiple functions of EM wave absorption, mechanical strength, thermal insulation, and flame retardancy. Herein, a novel carbon fiber reinforced C/SiOC aerogel (CF/CS) composite is successfully prepared by sol-gel impregnation combined with an ambient drying process for the first time. The density of the obtained CF/CS composites can be controlled just by changing sol-gel impregnation cycles (original carbon fiber felt (S0), and samples with one (S1) and two (S2) impregnation cycles are 0.249, 0.324, and 0.402 g cm-3, respectively), allowing for efficient tuning of their properties. Remarkably, S2 displays excellent microwave absorption properties, with an optimal reflection loss of -65.45 dB, which is significantly improved than S0 (-10.90 dB). Simultaneously, compared with S0 (0.75 and 0.30 MPa in the x/y and z directions), the mechanical performance of S2 is dramatically improved with a maximum compressive strength of 10.37 and 4.93 MPa in the x/y and z directions, respectively. Moreover, CF/CS composites show superior thermal insulation capability than S0 and obtain good flame-retardant properties. This work provides valuable guidance and inspiration for the development of multifunctional EM wave absorbers.

3.
Stem Cells ; 41(6): 628-642, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36951300

RESUMO

Migration of mesenchymal stem cells (MSCs) to the site of injury is crucial in transplantation therapy. Studies have shown that cell migration is regulated by the cellular microenvironment and accompanied by changes in cellular metabolism. However, limited information is available about the relationship between MSC migration and cellular metabolism. Here, we show that basic fibroblast growth factor (bFGF) promotes the migration of MSCs with high levels of glycolysis and high expression of hexokinase 2 (HK2), a rate-limiting enzyme in glycolysis. The enhancement of glycolysis via the activation of HK2 expression promoted the migration of MSCs, whereas the inhibition of glycolysis, but not of oxidative phosphorylation, inhibited the bFGF-induced migration of these cells. Furthermore, bFGF enhanced glycolysis by increasing HK2 expression, which consequently promoted ß-catenin accumulation, and the inhibition of glycolysis inhibited the bFGF-induced accumulation of ß-catenin. When the accumulation of glycolytic intermediates was altered, phosphoenolpyruvate was found to be directly involved in the regulation of ß-catenin expression and activation, suggesting that bFGF regulates ß-catenin signaling through glycolytic intermediates. Moreover, transplantation with HK2-overexpressing MSCs significantly improved the effect of cell therapy on skull injury in rats. In conclusion, we propose a novel glycolysis-dependent ß-catenin signaling regulatory mechanism and provide an experimental and theoretical basis for the clinical application of MSCs.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Células-Tronco Mesenquimais , Animais , Ratos , beta Catenina/metabolismo , Movimento Celular , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glicólise , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt
4.
BMC Med Imaging ; 24(1): 126, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807064

RESUMO

BACKGROUND: Automated Breast Ultrasound (AB US) has shown good application value and prospects in breast disease screening and diagnosis. The aim of the study was to explore the ability of AB US to detect and diagnose mammographically Breast Imaging Reporting and Data System (BI-RADS) category 4 microcalcifications. METHODS: 575 pathologically confirmed mammographically BI-RADS category 4 microcalcifications from January 2017 to June 2021 were included. All patients also completed AB US examinations. Based on the final pathological results, analyzed and summarized the AB US image features, and compared the evaluation results with mammography, to explore the detection and diagnostic ability of AB US for these suspicious microcalcifications. RESULTS: 250 were finally confirmed as malignant and 325 were benign. Mammographic findings including microcalcifications morphology (61/80 with amorphous, coarse heterogeneous and fine pleomorphic, 13/14 with fine-linear or branching), calcification distribution (189/346 with grouped, 40/67 with linear and segmental), associated features (70/96 with asymmetric shadow), higher BI-RADS category with 4B (88/120) and 4 C (73/38) showed higher incidence in malignant lesions, and were the independent factors associated with malignant microcalcifications. 477 (477/575, 83.0%) microcalcifications were detected by AB US, including 223 malignant and 254 benign, with a significantly higher detection rate for malignant lesions (x2 = 12.20, P < 0.001). Logistic regression analysis showed microcalcifications with architectural distortion (odds ratio [OR] = 0.30, P = 0.014), with amorphous, coarse heterogeneous and fine pleomorphic morphology (OR = 3.15, P = 0.037), grouped (OR = 1.90, P = 0.017), liner and segmental distribution (OR = 8.93, P = 0.004) were the independent factors which could affect the detectability of AB US for microcalcifications. In AB US, malignant calcification was more frequent in a mass (104/154) or intraductal (20/32), and with ductal changes (30/41) or architectural distortion (58/68), especially with the both (12/12). BI-RADS category results also showed that AB US had higher sensitivity to malignant calcification than mammography (64.8% vs. 46.8%). CONCLUSIONS: AB US has good detectability for mammographically BI-RADS category 4 microcalcifications, especially for malignant lesions. Malignant calcification is more common in a mass and intraductal in AB US, and tend to associated with architectural distortion or duct changes. Also, AB US has higher sensitivity than mammography to malignant microcalcification, which is expected to become an effective supplementary examination method for breast microcalcifications, especially in dense breasts.


Assuntos
Neoplasias da Mama , Calcinose , Ultrassonografia Mamária , Humanos , Calcinose/diagnóstico por imagem , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Ultrassonografia Mamária/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Adulto , Idoso , Mamografia/métodos , Idoso de 80 Anos ou mais
5.
Clin Immunol ; 253: 109685, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37406980

RESUMO

Inducing tumor-specific T cell responses and regulating suppressive tumor microenvironments have been a challenge for effective tumor therapy. CpG (ODN), the Toll-like receptor 9 agonist, has been widely used as adjuvants of cancer vaccines to induce T cell responses. We developed a novel adjuvant to improve the targeting of lymph nodes. CpG were modified with lipid and glycopolymers by the combination of photo-induced RAFT polymerization and click chemistry, and the novel adjuvant was termed as lipid-glycoadjuvant@AuNPs (LCpG). OVA protein was used as model antigen and melanoma model was established to test the immunotherapy effect of the adjuvant. In tumor model, the antitumor effect and mechanism of LCpG on the response of CTLs were examined by flow cytometry and cell cytotoxicity assay. The effects of LCpG on macrophage polarization and Tregs differentiation in tumor microenvironment were also studied by cell depletion assay and cytokine neutralization assay. We also tested the therapeutic effect of the combination of the adjuvant and anti-PD-1 treatment. LCpG could be rapidly transported to and retained longer in the lymphoid nodes than unmodified CpG. In melanoma model, LCpG controlled both primary tumor and its metastasis, and established long-term memory. In spleen and tumor draining lymphoid nodes, LCpG activated tumor-specific Tc1 responses, with increased CD8+ T-cell proliferation, antigen-specific Tc1 cytokine production and specific-tumor killing capacity. In tumor microenvironments, antigen-specific Tc1 induced by the LCpG promoted CTL infiltration, skewed tumor associated macrophages to M1 phenotype, regulated Treg and induced proinflammatory cytokines production in a CTL-derived IFN-γ-dependent manner. In vivo cell depletion and adoptive transfer experiments confirmed that antitumor activity of LCpG included vaccine was mainly dependent on CTL-derived IFN-γ. The anti-tumor efficacy of LCpG was dramatically enhanced when combined with anti-PD1 immunotherapy. LCpG was a promising adjuvant for vaccine formulation which could augment tumor-specific Tc1 activity, and regulate tumor microenvironments.


Assuntos
Vacinas Anticâncer , Melanoma , Nanopartículas Metálicas , Animais , Camundongos , Microambiente Tumoral , Interferon gama/metabolismo , Ouro/metabolismo , Ouro/farmacologia , Linfócitos T CD8-Positivos , Adjuvantes Imunológicos , Melanoma/metabolismo , Lipídeos/farmacologia , Camundongos Endogâmicos C57BL
6.
J Hum Genet ; 68(2): 73-80, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36482122

RESUMO

AIM: To investigate the occurrence of mosaicism in epilepsy probands and their parents using amplicon-based deep sequencing (ADS). METHODS: Patients were recruited from the outpatient of Peking University First Hospital. Two hundred and sixty-four probands with pathogenic variants tested by next-generation sequencing (NGS) were enrolled. RESULTS: Mosaic variants were detected in seventeen disease-associated genes from 20 probands, 5 paternal, and 6 maternal parents. The frequency of mosaicism was 11.74% (31/264). Mosaicism in 11 genes was identified from 20 probands with the mutant allelic fractions (MAFs) of 12.95-38.00% in autosomal dominant genes. Five paternal mosaicisms were identified in genes with a MAF of 6.30-20.99%, and six maternal mosaic individuals with a MAF of 2.07-21.90%. Only four mosaic parents had milder seizure history. The affected sibling had the same phenotype consistent with that of the proband, who inherited the variant of SLC1A2 or STXBP1 from their unaffected mosaic mothers, respectively. INTERPRETATION: Mosaic phenomenon is not rare in families with epilepsy. Phenotypes of mosaic parents were milder or normal. Mosaicism detection is helpful to identify the mutation origin and it provides a theoretical basis for prenatal diagnosis of family reproduction. ADS is a reliable way of mosaicism detection for clinical application.


Assuntos
Epilepsia , Mosaicismo , Humanos , Epilepsia/genética , Mutação , Genômica , Sequenciamento de Nucleotídeos em Larga Escala
7.
J Clin Ultrasound ; 51(6): 1039-1047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37096417

RESUMO

PURPOSE: To investigate the efficiency and impact factors of anatomical intelligence for breast (AI-Breast) and hand-held ultrasound (HHUS) in lesion detection. METHODS: A total of 172 outpatient women were randomly selected, underwent AI-Breast ultrasound (Group AI) once and HHUS twice. HHUS was performed by breast imaging radiologists (Group A) and general radiologists (Group B). For the AI-Breast examination, a trained technician performed the whole-breast scan and data acquisition, while other general radiologists performed image interpretation. The examination time and lesion detection rate were recorded. The impact factors for breast lesion detection, including breast cup size, number of lesions, and benign or malignant lesions were analyzed. RESULTS: The detection rates of Group AI, A, and B were 92.8 ± 17.0%, 95.0 ± 13.6%, and 85.0 ± 22.9%, respectively. Comparable lesion detection rates were observed in Group AI and Group A (P > 0.05), but a significantly lower lesion detection rate was observed in Group B compared to the other two (both P < 0.05). Regarding missed diagnosis rates of malignant lesions, comparable performance was observed in Group AI, Group A, and Group B (8% vs. 4% vs. 14%, all P > 0.05). Scan times of Groups AI, A, and B were 262.15 ± 40.4 s, 237.5 ± 110.3 s, 281.2 ± 86.1 s, respectively. The scan time of Group AI was significantly higher than Group A (P < 0.01), but was slightly lower than Group B (P > 0.05). We found a strong linear correlation between scan time and cup size in Group AI (r = 0.745). No impacts of cup size and number of lesions were found on the lesion detection rate in Group AI (P > 0.05). CONCLUSIONS: With the assist of AI-Breast system, the lesion detection rate of AI-Breast ultrasound was comparable to that of a breast imaging radiologist and superior to that of the general radiologist. AI-Breast ultrasound may be used as a potential approach for breast lesions surveillance.


Assuntos
Neoplasias da Mama , Interpretação de Imagem Assistida por Computador , Feminino , Humanos , Sensibilidade e Especificidade , Interpretação de Imagem Assistida por Computador/métodos , Mama/diagnóstico por imagem , Mama/patologia , Ultrassonografia Mamária/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia
8.
Photosynth Res ; 154(3): 397-411, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35974136

RESUMO

Clean and sustainable H2 production is crucial to a carbon-neutral world. H2 generation by Chlamydomonas reinhardtii is an attractive approach for solar-H2 from H2O. However, it is currently not large-scalable because of lacking desirable strains with both optimal H2 productivity and sufficient knowledge of underlying molecular mechanism. We hereby carried out extensive and in-depth investigations of H2 photoproduction of hpm91 mutant lacking PGR5 (Proton Gradient Regulation 5) toward its up-scaling and fundamental mechanism issues. We show that hpm91 is at least 100-fold scalable (up to 10 L) with continuous H2 collection of 7287 ml H2/10L-HPBR in averagely 26 days under sulfur deprivation. Also, we show that hpm91 is robust and active during sustained H2 photoproduction, most likely due to decreased intracellular ROS relative to wild type. Moreover, we obtained quantitative proteomic profiles of wild type and hpm91 at four representing time points of H2 evolution, leading to 2229 and 1350 differentially expressed proteins, respectively. Compared to wild type, major proteome alterations of hpm91 include not only core subunits of photosystems and those related to anti-oxidative responses but also essential proteins in photosynthetic antenna, C/N metabolic balance, and sulfur assimilation toward both cysteine biosynthesis and sulfation of metabolites during sulfur-deprived H2 production. These results reveal not only new insights of cellular and molecular basis of enhanced H2 production in hpm91 but also provide additional candidate gene targets and modules for further genetic modifications and/or in artificial photosynthesis mimics toward basic and applied research aiming at advancing solar-H2 technology.


Assuntos
Chlamydomonas reinhardtii , Chlamydomonas , Prótons , Proteômica , Hidrogênio/metabolismo , Fotossíntese/fisiologia , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Enxofre/metabolismo
9.
Physiol Plant ; 174(1): e13625, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35023161

RESUMO

Cuticular lipids, including wax and cutin, protect plants against external environmental stress. The relationship between the cuticle properties and salt tolerance is not clear. In this article, photosynthetic and physiological characteristics related to water use and cuticle permeability were assessed in the leaves of Thellungiella salsuginea under NaCl stress. The chemical composition of wax and cutin monomers, and the expression of cuticle-associated genes were also analyzed. The results showed that the net photosynthetic rate and stomatal conductance in the leaves of T. salsuginea decreased, and the water use efficiency increased with increasing NaCl concentration. Salt stress caused a significant increase in total wax, but total cutin monomers only increased under high salt. Transcriptome sequencing and lipid metabolism pathway analysis were performed on rosette leaves of T. salsuginea after 24 h of NaCl treatment. We analyzed the expression of 42 genes involved in cuticle lipid metabolism, and found that most of them exhibited higher expression levels at 0.15 mol L-1 NaCl, but lower expression levels at 0.3 mol L-1 NaCl. The expression of 12 of these genes was further detected by qRT-PCR after 1 week of NaCl treatment: most of them were upregulated both under low and high NaCl stress. Hence, we speculate that the cuticle acts as an adaptive trait in T. salsuginea in salty environments.


Assuntos
Brassicaceae , Regulação da Expressão Gênica de Plantas , Brassicaceae/metabolismo , Expressão Gênica , Folhas de Planta/fisiologia , Cloreto de Sódio/metabolismo , Cloreto de Sódio/farmacologia
10.
Clin Rehabil ; 36(5): 573-596, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34898298

RESUMO

OBJECTIVE: To investigate the effect of virtual reality on arm motor impairment, activity limitation, participation restriction, and quality of life in patients with stroke. To determine potential moderators that affect the efficacy of virtual reality. DATA SOURCES: CINAHL, Medline, PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, and Wanfang Data from inception to October 23, 2021. REVIEW METHODS: Randomized controlled trials that investigated the effect of virtual reality on arm recovery in adult patients with stroke compared to conventional therapy or sham control were included. Physiotherapy Evidence Database Scale was used to assess the methodological quality of each study. RESULTS: Forty studies with 2018 participants were identified. Quality of included studies was fair to high. Virtual reality exhibited better effects on overall arm function (g = 0.28, p < 0.001), motor impairment (g = 0.36, p < 0.001) and activity limitation (daily living) (g = 0.24, p < 0.001) compared with the control group. No significant improvement was observed in participation restriction and activity limitation (specific task). The result for quality of life was described qualitatively. Subgroup analyses demonstrated that immersive virtual reality produced a greater beneficial effect (g = 0.60, p < 0.001). Patients with moderate to severe arm paresis could make more progress after training (g = 0.71, p < 0.001). CONCLUSION: Virtual reality is recommended for improving motor impairment and activities of daily living after stroke and is favorable to patients with moderate to severe paresis. An immersive design could produce greater improvement.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Terapia de Exposição à Realidade Virtual , Realidade Virtual , Atividades Cotidianas , Adulto , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Extremidade Superior
11.
J Exp Bot ; 72(8): 2857-2876, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33471899

RESUMO

With the growth of the global population and the increasing frequency of natural disasters, crop yields must be steadily increased to enhance human adaptability to risks. Pre-harvest sprouting (PHS), a term mainly used to describe the phenomenon in which grains germinate on the mother plant directly before harvest, is a serious global problem for agricultural production. After domestication, the dormancy level of cultivated crops was generally lower than that of their wild ancestors. Although the shortened dormancy period likely improved the industrial performance of cereals such as wheat, barley, rice, and maize, the excessive germination rate has caused frequent PHS in areas with higher rainfall, resulting in great economic losses. Here, we systematically review the causes of PHS and its consequences, the major indicators and methods for PHS assessment, and emphasize the biological significance of PHS in crop production. Wheat quantitative trait loci functioning in the control of PHS are also comprehensively summarized in a meta-analysis. Finally, we use Arabidopsis as a model plant to develop more complete PHS regulatory networks for wheat. The integration of this information is conducive to the development of custom-made cultivated lines suitable for different demands and regions, and is of great significance for improving crop yields and economic benefits.


Assuntos
Grão Comestível , Oryza , Grão Comestível/genética , Germinação , Oryza/genética , Dormência de Plantas , Locos de Características Quantitativas/genética , Triticum/genética
12.
J Nanobiotechnology ; 19(1): 376, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794428

RESUMO

ABSTARCT: BACKGROUND: Cytosine-phosphate-guanine (CpG) dinucleotides has been used as adjuvants for cancer immunotherapy. However, unmodified CpG are not very efficient in clinical trials. Glucose, ligand of C-type lectin receptors (CLRs), can promote DC maturation and antigen presentation, which is the first step of induction of adaptive immune responses. Therefore, conjugation of type B CpG DNA to glucose-containing glycopolymers may enhance the therapeutic effects against tumor by CpG-based vaccine. METHODS: gCpG was developed by chemical conjugation of type B CpG DNA to glucose-containing glycopolymers. The therapeutic effects of gCpG-based vaccine were tested in both murine primary melanoma model and its metastasis model. RESULTS: gCpG based tumor vaccine inhibited both primary and metastasis of melanoma in mice which was dependent on CD8 + T cells and IFNγ. In tumor microenvironment, gCpG treatment increased Th1 and CTL infiltration, increased M1 macrophages, decreased Tregs and MDSCs populations, and promoted inflammatory milieu with enhanced secretion of IFNγ and TNFα. The anti-tumor efficacy of gCpG was dramatically enhanced when combined with anti-PD1 immunotherapy. CONCLUSIONS: We confirmed that gCpG was a promising adjuvant for vaccine formulation by activating both tumor-specific Th1 and Tc1 responses, and regulating tumor microenvironments.


Assuntos
Antineoplásicos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Ouro/química , Nanopartículas Metálicas/química , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Camundongos , Camundongos Endogâmicos C57BL
13.
J Clin Lab Anal ; 35(9): e23818, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34403504

RESUMO

BACKGROUND: Examining tumor KRAS/NRAS/BRAF/PIK3CA status in metastatic colorectal cancer (mCRC) is essential for treatment selection and prognosis evaluation. Cell-free DNA (cfDNA) in plasma is a feasible source for tumor gene analysis. METHODS: In this study, we recruited mCRC patients and analyzed their KRAS/NRAS/BRAF/PIK3CA status in cfDNA using two platforms, next-generation sequencing (NGS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF). The performance between the two platforms and the concordance rate between cfDNA and tissue were analyzed. The relationship between cfDNA-related variables and clinical variables was also assessed. Tumor mutations in cfDNA from patients receiving continuous treatments were monitored in the follow-ups. RESULTS: Next-generation sequencing and MALDI-TOF had similar specificity (100.0% vs. 99.3%) and negative predictive value (99.9% vs. 99.4%), whereas NGS had higher sensitivity (97.1% vs. 85.3% of MALDI-TOF) and positive predictive value (100% vs. 82.9% of MALDI-TOF). The overall concordance rate of NGS and MALDI-TOF was 98.6%. For the reportable types of mutations in both cfDNA and tissue, the concordance rate was 96.1%. Among 28 tissue-positive patients, the allele frequencies of tumor mutations in cfDNA were higher in patients with primary tumor burden (p = 0.0141). Both CEA and CA 19-9 were positively correlated with cfDNA concentration (r = 0.3278 and r = 0.3992). The allele frequencies of tumor mutations changed with disease progression. CONCLUSIONS: Next-generation sequencing showed slightly better performance in detecting cfDNA mutations and was more suitable for clinical practice. cfDNA-related variables reflected the tumor status and showed a promising potential in monitoring disease progression.


Assuntos
Ácidos Nucleicos Livres/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/patologia , GTP Fosfo-Hidrolases/genética , Proteínas de Membrana/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Idoso , Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/análise , Neoplasias Colorretais/genética , Feminino , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
14.
Zygote ; 29(4): 286-292, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653422

RESUMO

To study the role of orexin A in the reproductive regulation of Mongolian sheep, ovine ovarian granulosa cells were cultured in vitro. The cells were divided into groups after luteinization, the experimental group was given orexin A and the transcriptome was sequenced together with that of the control group. The different genes related to reproduction were screened out. qRT-PCR, western blot and enzyme-linked immunosorbent assay (ELISA) were used to verify the selected genes and detect the effect on progesterone secretion. In total, 123 differentially expressed genes were obtained by sequencing. Six genes with high expression related to reproduction (PRRT2, ABCG1, SOX4, TBX3, ID1 and ATP8) were screened. The results of qRT-PCR were consistent with those of sequencing; western blot and ELISA were used to verify the protein levels of steroidogenic acute regulatory protein (StAR) and its related PRRT2 and ABCG1, and to detect their effect on progesterone secretion. Validation results were consistent with those of qRT-PCR and sequencing. The experimental group was given orexin A and compared with the control group. Expression of PRRT2 protein was significantly increased (P < 0.05), ABCG1 protein expression was significantly decreased (P < 0.05), StAR expression was significantly increased (P < 0.05), and progesterone secretion was significantly increased (P < 0.05). The results showed that orexin A promoted the expression of StAR by upregulating PRRT2 and downregulating ABCG1, therefore affecting secretion of progesterone. Gene expression characteristics of orexin A affecting progesterone secretion were preliminarily explored; this study provides a theoretical basis for further study on signalling pathways and reproductive regulation in Mongolian sheep.


Assuntos
Ovário , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Animais , Células Cultivadas , Feminino , Células da Granulosa , Luteinização , Proteínas do Tecido Nervoso , Orexinas , Polissacarídeos , Progesterona , Ovinos , Carneiro Doméstico
15.
Environ Geochem Health ; 43(4): 1599-1607, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060864

RESUMO

Hyperaccumulator plants are ideal models for investigating the regulatory mechanisms of plant metal homeostasis and environmental adaptation due to their notable traits of metal accumulation and tolerance. These traits may benefit either the biofortification of essential mineral nutrients or the phytoremediation of nonessential toxic metals. A common mechanism by which elevated expression of key genes involved in metal transport or chelation contributes to hyperaccumulation and hypertolerance was proposed mainly from studies examining two Brassicaceae hyperaccumulators, namely Arabidopsis halleri and Noccaea caerulescens (formerly Thlaspi caerulescens). Meanwhile, recent findings regarding systems outside the Brassicaceae hyperaccumulators indicated that functional enhancement of key genes might represent a strategy evolved by hyperaccumulator plants. This review provides a brief outline of metal hyperaccumulation in plants and highlights commonalities and differences among various hyperaccumulators.


Assuntos
Metais/metabolismo , Plantas/metabolismo , Biodegradação Ambiental
16.
J Cell Physiol ; 235(7-8): 5777-5786, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32048287

RESUMO

High-throughput messenger RNA (mRNA) analysis has become a powerful tool for exploring tumor recurrence or metastasis mechanisms. Here, we constructed a signature to predict the recurrence risk of Stages II and III gastric cancer (GC) patients. A least absolute shrinkage and selection operator method Cox regression model was utilized to construct the signature. Using this method, a 16-mRNA signature was identified to be associated with the relapse-free survival of Stages II and III GCs in training dataset GSE62254 (n = 194). Then this signature was validated in an independent Gene Expression Omnibus cohort GSE26253 (n = 297) and a dataset of The Cancer Genome Atlas (TCGA; n = 235). This classifier could successfully screen out the high-risk Stages II and III GCs in the training cohort (hazard ratio [HR] = 40.91; 95% confidence interval [CI] = 5.58-299.7; p < .0001). Analysis in two independent validation cohorts yielded consistent results (GSE26253: HR = 1.69, 95% CI = 1.17-2.43,; p = .0045; TCGA: HR = 2.01, 95% CI = 1.13-3.56, p = .0146). Cox regression analyses revealed that the risk score derived from this signature was an independent risk factor in Stages II and III GCs. Besides, a nomogram was constructed to serve clinical practice. Through gene set variation analysis, we found several gene sets associated with chemotherapeutic drug resistance and tumor metastasis significantly enriched in high-risk patients. In summary, this 16-mRNA signature can be used as a powerful tool for prognostic evaluation and help clinicians identify high-risk patients.


Assuntos
Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia/genética , RNA Mensageiro/genética , Neoplasias Gástricas/genética , Idoso , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Nomogramas , Prognóstico , Neoplasias Gástricas/patologia , Transcriptoma
17.
BMC Cancer ; 20(1): 1006, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066758

RESUMO

BACKGROUND: The aim of this study was to explore the utility of circulating free DNA (cfDNA) in the evaluation of clinical tumor burden and survival in Chinese patients with metastatic colorectal cancer (mCRC) and to preliminarily summarize some metastatic characteristics associated with mutational status. METHODS: A panel covering a total of 197 hotspot mutations of KRAS, NRAS, BRAF and PIK3CA was used to evaluate the mutational status in plasma by next-generation sequencing (NGS) technology in 126 patients with mCRC. An amplification-refractory mutation system (ARMS) was used to analyze genomic DNA from matched tissue samples. Clinical markers including carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), carbohydrate antigen 125 (CA125), neuron-specific enolase (NSE) and lactate dehydrogenase (LDH) in serum and the sum of all tumor diameters on CT or PET/CT were collected to indicate clinical tumor burden. The correlations between cfDNA and clinical tumor burden were analyzed using Pearson correlation and linear regression models. The median progression-free survival (PFS) and 1-year overall survival (OS) rates were calculated by Kaplan-Meier (K-M) survival analysis. RESULTS: Of the 126 enrolled patients, patients who were tested positive for mutations in plasma accounted for 45.2% (57/126). Mutations in KRAS, NRAS, BRAF and PIK3CA were detected in 37.3% (47/126), 1.6% (2/126), 3.2% (4/126) and 13.5% (17/126) of patients, respectively. The overall concordance rate of mutational status between plasma and matched tissues was 78.6% (99/126). Sixteen patients had mutations in plasma that were not detected in tissue, including some rare hotspot mutations. The cfDNA concentration was significantly correlated with the levels of clinical markers, especially CEA (P < 0.0001, Pearson r = 0.81), LDH (P < 0.0001, Pearson r = 0.84) and the sum of tumor diameters (P < 0.0001, Pearson r = 0.80). Patients with a high cfDNA concentration (> 17.91 ng/ml) had shorter median progression-free survival (6.6 versus 11.7 months, P < 0.0001) and lower 1-year overall survival rate (56% versus 94%, P < 0.0001) than those with a low cfDNA concentration (≤17.91 ng/ml). The most common metastatic site was the liver (77.8%), followed by the lymph nodes (62.7%), lung (40.5%), peritoneum (14.3%) and bone (10.3%), in all patients. There was no significant difference in metastasis between different mutational statuses. CONCLUSION: Analyzing mutations in plasma could provide a more comprehensive overview of the mutational landscape than analyzing mutations in tissue. The cfDNA concentration could be a quantitative biomarker of tumor burden and could predict survival in Chinese patients with mCRC.


Assuntos
Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Análise Mutacional de DNA/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/genética , Feminino , GTP Fosfo-Hidrolases/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Metástase Neoplásica , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Análise de Sobrevida , Carga Tumoral
18.
Mol Biol Rep ; 47(9): 6561-6572, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32789574

RESUMO

After confirmation of the presence of adiponectin (ADPN) receptors and intra-cellular binding proteins in coronary artery smooth muscle cells (VSMC), we tested the hypotheses that, in acute insulin resistance: (i) the activation/inactivation of metabolic and mitogenic insulin signaling pathways are inversely affected by ADPN and, (ii) changes in VSMC migration/proliferation rates correlate with signal activity/inactivity. In primary cultures of VSMC exposed to high glucose and palmitate plus insulin, the expression of PI-3 kinase (Akt and m-TOR), MAP-Kinase (Erk and p-38) molecules, and inflammatory markers (TLR-4 and IkB-α) were assessed with Western blot, in the absence/presence of AdipoRon (AR). Migration and proliferation rates were measured in similar experimental conditions. There were decreases of ~ 25% (p-Akt) and 40-60% (p-mTOR) expressions with high glucose/palmitate, which reversed when AR was added were. Elevations in p-Erk and p-p38 expressions were obliterated by AR. Although, no changes were detected with high glucose and palmitate, when AR was added, a decline in inflammatory activity was substantiated by a ~ 50% decrease in TLR-4 and 40-60% increase in IkBα expression. Functional assays showed 10-20% rise in VSMC proliferation with high glucose and palmitate, but addition of AR lead to 15-25% decline. The degree of VSMC migration was reduced with AR addition by ~ 15%, ~ 35% and 55%, in VSMC exposed to 5 mM, 25 mM glucose and 25 mM + 200 µM palmitate, respectively. Changes in intracellular molecular messaging in experiments mimicking acute insulin resistance suggest that anti-inflammatory and anti-atherogenic actions of ADPN in VSMC are mediated via insulin signaling pathways.


Assuntos
Adiponectina/metabolismo , Insulina/isolamento & purificação , Insulina/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Piperidinas/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Humanos , Proteínas I-kappa B/metabolismo , Inflamação/metabolismo , Insulina/metabolismo , Palmitatos/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Adiponectina/agonistas , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno
19.
Exp Cell Res ; 379(1): 65-72, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30898547

RESUMO

Olfactory ensheathing cells (OECs) are ideal candidates for cell-based therapies aimed at repairing spinal cord injury (SCI). Accurate targeting of OECs to the lesion site is critical to reconstructing the impaired nervous system. However, the key factors guiding the homing of transplanted OECs to the damaged area after SCI are still unclear. Here, we demonstrate that lysophosphatidic acid (LPA) can significantly facilitate the homing of OECs after SCI in rats. First, we found that OECs exhibited a robust chemotaxis response to LPA in vitro, with LPAR1 being predominant receptor expressed on OECs. We further found that ß-catenin signaling plays an important role in LPA-induced OEC migration. Moreover, silencing LPAR1 not only abolished the migration of OECs but also prevented ERK1/2 phosphorylation and ß-catenin activation, suggesting that LPAR1 ligation serves to activate the ERK1/2 and ß-catenin pathways in LPA-induced OEC chemotactic migration. Finally, cell transplantation experiments confirmed that endogenous LPA, which was observed to be produced at the lesion site after SCI in rat, is a key chemokine that facilitates OEC migration to the injury center. Collectively, our data provide a further description of the homing effects of LPA and a mechanism by which transplanted OECs migrate to the injured area after SCI in rats.


Assuntos
Lisofosfolipídeos/metabolismo , Bulbo Olfatório/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia , Animais , Movimento Celular/fisiologia , Transplante de Células/métodos , Células Cultivadas , Sistema de Sinalização das MAP Quinases/fisiologia , Bulbo Olfatório/citologia , Fosforilação/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Ácidos Lisofosfatídicos/metabolismo , Transdução de Sinais/fisiologia , Medula Espinal/citologia , Medula Espinal/metabolismo , beta Catenina/metabolismo
20.
J Phycol ; 56(3): 784-797, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32110841

RESUMO

Chaetoceros debilis is considered one of the most abundant and widespread diatoms in the coastal marine phytoplankton, and is often used in research studies ranging from ecophysiology and molecular biology to oceanography and aquaculture. To clarify the species delineation of C. debilis and explore the diversity among C. debilis sensu lato taxa, monoclonal strains were established from different geographical regions, including the Danish coast, close to the type locality of C. debilis, the Denmark Strait (between Iceland and Greenland) as well as the Taiwan Strait, East China Sea and Daya Bay, South China Sea. Vegetative cells and resting spores were examined using light and electron microscopy. The hypervariable D1-D3 region of the nuclear large subunit ribosomal gene and the small subunit ribosomal gene were sequenced to address phylogenetic relationships. In both SSU and LSU trees, the C. debilis sensu lato strains clustered in four distinct clades. Culture material from the type locality was, along with molecular data, used to delineate and emend the description of C. debilis. Based on molecular data and detailed morphological features, one of the clades originating from Chinese waters was described as C. galeatus sp. nov., characterized by curved and helical chains, elliptical valves, and smooth and helmet-shaped primary valves of the resting spores. The remaining two clades, which also represent two novel taxa, C. cf. debilis-1 and C. cf. debilis-2, were not formally described as new species due to the insufficient information on their morphology.


Assuntos
Diatomáceas , China , DNA Ribossômico , Diatomáceas/genética , Filogenia , Fitoplâncton , Análise de Sequência de DNA , Taiwan
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