RESUMO
Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer's disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Testes Neuropsicológicos , Disfunção Cognitiva/patologia , Encéfalo , Substância Cinzenta/patologia , Doença de Alzheimer/patologia , Imageamento por Ressonância Magnética , Atrofia/patologia , Diagnóstico PrecoceRESUMO
Mulch coverage of mining tailings can create anaerobic conditions and consequently establish an anoxic environment that promotes the metabolic processes of anaerobic microorganisms. This anoxic environment has the potential to decrease heavy metal mobility and bioavailability. While tailings exposed to sunlight have been extensively studied, research on the effects of microbial-mediated geochemical cycling of heavy metals in mulch-covered tailings is scarce. This study aimed to examine the effects of mulch coverage-induced alterations in the structures of tailing microbial communities on the biogeochemical processes associated with heavy metals. Mulch coverage significantly reduced the pH of the tailings and the tailings exhibited heavy metal bioavailability. Random forest analysis demonstrated that mulch coverage-induced changes in the As/Cd-contaminated fractions and nutrients (total organic carbon and total nitrogen) were the most crucial predictors of microbial diversity and ecological clusters in the tailings. Notably, different from direct metal(loid) immobilization, mulch coverage can facilitate heavy metal immobilization in tailings by promoting microbial-mediated Fe, S, and As reduction. Overall, this study demonstrated that mulch coverage of tailings contributed to a reduction in heavy metal mobilization, which can be attributed to shifts in microbial-mediated Fe, S, and As reduction processes.The study provides valuable insights into the potential of mulch coverage as a remediation strategy and underscores the importance of microbial-mediated processes in managing heavy metal pollution in tailing systems.
RESUMO
Transient gene expression system is an important tool for rapid production of recombinant proteins in Chinese hamster ovary (CHO) cells. However, their low productivity is the main hurdle to overcome. An effective approach through which to obtain high protein yield involves targeting transcriptional, post-transcriptional events (PTEs), and culture conditions. Here, we investigated the effects of protein disulfide isomerase (PDI) and spliced X-box binding protein 1 (XBP-1s) co-overexpression combined with mild hypothermia on the transient yields of recombinant proteins in CHO cells. The results showed that the gene of interest (GOI) and the PDI/XBP-1s helper vector at a co-transfection ratio of 10:1 could obviously increase transient expression level of recombinant protein in CHO cells. However, PDI/XBP-1s overexpression had no significance effect on the mRNA levels of the recombinant protein, suggesting that it targeted PTEs. Moreover, the increased production was due to the enhancing of cell specific productivity, not related to cell growth, viability, and cell cycle. In addition, combined PDI/XBP-1s co-overexpression and mild hypothermia could further improve Adalimumab expression, compared to the control/37 °C and PDI/XBP-1s/37 °C, the Adalimumab volume yield of PDI/XBP-1s/33 °C increased by 203% and 142%, respectively. Mild hypothermia resulted in 3.52- and 2.33-fold increase in the relative mRNA levels of PDI and XBP-1s, respectively. In conclusion, the combination of PDI/XBP-1s overexpression and culture temperature optimization can achieve higher transient expression of recombinant protein, which provides a synergetic strategy to improve transient production of recombinant protein in CHO cells.
Assuntos
Hipotermia , Fatores de Transcrição , Cricetinae , Animais , Células CHO , Cricetulus , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Adalimumab/genética , Hipotermia/genética , Proteínas Recombinantes , Transfecção , Transgenes , RNA MensageiroRESUMO
The insufficiently long RF saturation duration and relaxation delay in chemical exchange saturation transfer (CEST)-MRI experiments may result in underestimation of CEST measurements. To maintain the CEST effect without prolonging the saturation duration and reach quasi-steady state (QUASS), a deep learning method was developed to reconstruct a QUASS CEST image pixel by pixel from non-steady-state CEST acquired in experiments. In this work, we established a tumor-bearing rat model on a 7 T horizontal bore small-animal MRI scanner, allowing ground-truth generation, after which a bidirectional long short-term memory network was formulated and trained on simulated CEST Z-spectra to reconstruct the QUASS CEST; finally, the ground truth yielded by experiments was used to evaluate the performance of the reconstruction model by comparing the estimates with the ground truth. For quantitation evaluation, linear regression analysis, structural similarity index (SSIM) and peak signal-to-noise ratio (peak SNR) were used to assess the proposed model in the QUASS CEST reconstruction. In the linear regression analysis of in vivo data, the coefficient of determination for six different representative frequency offsets was at least R2 = 0.9521. Using the SSIM and peak SNR as evaluation metrics, the reconstruction accuracies of in vivo QUASS CEST were found to be 0.9991 and 46.7076, respectively. Experimental results demonstrate that the proposed model provides a robust and accurate solution for QUASS CEST reconstruction using a deep learning mechanism.
RESUMO
OBJECTIVES: To evaluate the imaging quality of a synthetic phase-sensitive inversion recovery (SyPSIR) vessel and to add value to T2-weighted imaging (T2WI) for extramural venous invasion (EMVI) detection in patients with rectal cancer. METHODS: Participants in this retrospective study underwent preoperative synthetic MRI between October 2020 and April 2022. SyPSIR image reconstruction was performed with a single inversion time of 10 ms. A junior and a senior radiologist evaluated the imaging quality, including overall imaging quality scores, motion artifact scores, and relative image signal intensity contrast between the tumor and peritumoral vessels (SItumor-vessel), of both T2WI and SyPSIR vessels. Differences in imaging quality between the two methods were assessed using the Wilcoxon signed-rank test and two-sample t-test. EMVI scores were recorded for T2WI and T2WI+SyPSIR vessel. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the diagnostic performance. RESULTS: A total of 106 patients (35 EMVI+ and 71 EMVI-) were evaluated. There were no statistically significant differences in the overall image quality scores, motion artifacts, or SItumor-vessel (p = 0.08-0.93) between the T2WI and SyPSIR vessels. On combining T2WI and SyPSIR vessels, the AUC for pathological EMVI+ diagnoses increased from 0.65 to 0.88 for the junior radiologist and from 0.86 to 0.96 for the senior radiologist. Furthermore, the sensitivity of the analyses by junior and senior radiologists increased from 0.40 to 0.77 and 0.49 to 0.86, respectively. CONCLUSION: A SyPSIR vessel can provide additional information to improve the diagnostic efficiency of pathological EMVI in rectal cancer, which may be beneficial for individualized clinical treatment. KEY POINTS: ⢠SyPSIR vessel and T2WI had similar imaging quality. ⢠EMVI evaluation in SyPSIR vessel has a high inter-observer agreement. ⢠The SyPSIR vessel has the potential to improve the diagnostic efficiency of EMVI detection in rectal cancer.
Assuntos
Neoplasias Retais , Humanos , Estudos Retrospectivos , Invasividade Neoplásica/patologia , Neoplasias Retais/patologia , Imageamento por Ressonância Magnética/métodos , Curva ROCRESUMO
Tungsten (W) is a critical material that is widely used in military applications, electronics, lighting technology, power engineering and the automotive and aerospace industries. In recent decades, overexploitation of W has generated large amounts of mine waste rocks, which generate elevated content of toxic elements and cause serious adverse effects on ecosystems and public health. Microorganisms are considered important players in toxic element migrations from waste rocks. However, the understanding of how the microbial community structure varies in W mine waste rocks and its key driving factors is still unknown. In this study, high-throughput sequencing methods were used to determine the microbial community profiles along a W content gradient in W mine waste rocks. We found that the microbial community structures showed clear differences across the different W levels in waste rocks. Notably, arsenic (As), instead of W and nutrients, was identified as the most important predictor influencing microbial diversity. Furthermore, our results also showed that As is the most important environmental factor that regulates the distribution patterns of ecological clusters and keystone ASVs. Importantly, we found that the dominant genera have been regulated by As and were widely involved in As biogeochemical cycling in waste rocks. Taken together, our results have provided useful information about the response of microbial communities to W mine waste rocks.
Assuntos
Arsênio , Microbiota , TungstênioRESUMO
CONTEXT: Danggui Buxue Decoction (DBD) is an effective complementary medicine in alleviating myelosuppression after chemotherapy (MAC). However, its mechanism of action is elusive. OBJECTIVE: To illustrate that regulating ß-hydroxybutyric acid (ß-OHB) metabolism and suppressing oxidative stress could be a potential mechanism of action for DBD in alleviating MAC. MATERIALS AND METHODS: After HPLC quantification and dose testing (3, 6 and 10 g/kg, gavage) of DBD, Sprague-Dawley rats were divided into control, cyclophosphamide (CTX) (30 mg/kg CTX for 5 days, intraperitoneal administration) and CTX + DBD groups (6 g/kg DBD for 14 days, gavage). Blood cell counts, thigh bone histological examination, ß-OHB levels, oxidative stress indices and HDAC1 activity were tested. The biological function of ß-OHB was verified in vitro (hBMSC cells were incubated in culture mediums that contained 40 µM CTX and ß-OHB in 0, 1, 2.5, 5, 10 mM) and in vivo (MAC rat model, 3 g/kg ß-OHB for 14 days, gavage). RESULTS: Rats in the CTX + DBD group showed upregulated blood cell counts (118-243%), ß-OHB levels (495 nmol/mL in blood, 122 nmol/mg in marrow supernatant) and downregulated HDAC1 activity (59%), and oxidative stress indices (60-85%). In vitro, 5 mM ß-OHB improved hBMSC cell migration (123%) and proliferation (131%). In vivo, rats treated with 3 g/kg ß-OHB showed upregulated blood cell counts (121-182%) and downregulated HDAC1 activity (64%) and oxidative stress indices (65-83%). DISCUSSION AND CONCLUSIONS: DBD, a traditional Chinese medicine, alleviates MAC by intervening in ß-OHB metabolism and oxidative stress.
Assuntos
Medicamentos de Ervas Chinesas , Ratos , Animais , Ácido 3-Hidroxibutírico , Ratos Sprague-Dawley , Medicamentos de Ervas Chinesas/farmacologia , Ciclofosfamida , Estresse OxidativoRESUMO
Matrix attachment regions (MARs) are DNA fragments with specific motifs that enhance transgenic expression; however, the characteristics and functions of these elements remain unclear. In this study, we designed and synthesized three short chimeric MARs, namely, SM4, SM5, and SM6, with different numbers and orders of motifs on the basis of the features and motifs of previously reported MARs, namely, SM1, SM2, and SM3, respectively. Expression vectors with six synthetic MARs flanking the down or upstream of the expression cassette for enhanced green fluorescence protein (EGFP) were constructed and introduced into Chinese hamster ovary (CHO) cells. Results indicated that the EGFP expression of the CHO cells with transfection bySM4, SM5, or SM6-containing vectors was higher than that of those containing SM1, SM2, or SM3 regardless of the MAR insertion position. The improving effect of SM5 was particularly pronounced. Transgenic expression was further enhanced with the increasing SM5 copy number. Bioinformatics analysis indicated that several arrangements of the DNA-binding motifs for CEBP, FAST, Hox, glutathione, and NMP4 may help increase transgenic expression levels and the average population of highly expressed cells. Our findings on novel synthetic MARs will help establish stable expression systems in mammalian cells.
Assuntos
Proteínas de Fluorescência Verde/metabolismo , Animais , Células CHO , Biologia Computacional , Cricetinae , Cricetulus , Vetores Genéticos/genética , Glutationa/metabolismo , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Estabilidade Proteica , Reação em Cadeia da Polimerase em Tempo RealRESUMO
BACKGROUND: Nanomedicine is a promising new approach to cancer treatment that avoids the disadvantages of traditional chemotherapy and improves therapeutic indices. However, the lack of a real-time visualization imaging technology to monitor drug distribution greatly limits its clinical application. Image-tracked drug delivery is of great clinical interest; it is useful for identifying those patients for whom the therapy is more likely to be beneficial. This paper discusses a novel nanomedicine that displays features of nanoparticles and facilitates functional magnetic resonance imaging but is challenging to prepare. RESULTS: To achieve this goal, we synthesized an acylamino-containing amphiphilic block copolymer (polyethylene glycol-polyacrylamide-polyacetonitrile, PEG-b-P(AM-co-AN)) by reversible addition-fragmentation chain transfer (RAFT) polymerization. The PEG-b-P(AM-co-AN) has chemical exchange saturation transfer (CEST) effects, which enable the use of CEST imaging for monitoring nanocarrier accumulation and providing molecular information of pathological tissues. Based on PEG-b-P(AM-co-AN), a new nanomedicine PEG-PAM-PAN@DOX was constructed by nano-precipitation. The self-assembling nature of PEG-PAM-PAN@DOX made the synthesis effective, straightforward, and biocompatible. In vitro studies demonstrate decreased cytotoxicity of PEG-PAM-PAN@DOX compared to free doxorubicin (half-maximal inhibitory concentration (IC50), mean ~ 0.62 µg/mL vs. ~ 5 µg/mL), and the nanomedicine more efficiently entered the cytoplasm and nucleus of cancer cells to kill them. Further, in vivo animal experiments showed that the nanomedicine developed was not only effective against breast cancer, but also displayed an excellent sensitive CEST effect for monitoring drug accumulation (at about 0.5 ppm) in tumor areas. The CEST signal of post-injection 2 h was significantly higher than that of pre-injection (2.17 ± 0.88% vs. 0. 09 ± 0.75%, p < 0.01). CONCLUSIONS: The nanomedicine with CEST imaging reflects the characterization of tumors and therapeutic functions has great potential medical applications.
Assuntos
Acrilamidas/síntese química , Antineoplásicos/química , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/química , Nanocápsulas/química , Polímeros/síntese química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Corantes Fluorescentes/química , Humanos , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Nus , Imagem Óptica/métodos , Distribuição TecidualRESUMO
OBJECTIVES: To investigate the effect of full-length fragment of DNA topoisomerase I gene (TOP1) matrix attachment regions (MARs) originating from the human genome on transgene expression in Chinese hamster ovary (CHO) cells and explore the underlying mechanisms. RESULTS: Results showed that TOP1 MAR cannot only enhance the transient and stable transgenic expression of enhanced green fluorescence protein (EGFP) but also increase long-term stability and ratio of positive colonies in transfected CHO cells with TOP1 MAR at the 5' or 3' ends of the EGFP expression cassette. Interestingly, the CHO cells were transfected with the 5',3' TOP1 MAR-containing vector featured the highest transient and stable expression, whereas those with the 3' TOP1 MAR-containing vector exhibited the most effective stability and ratio of positive colonies. We also observed that transgene copy numbers and mRNA of egfp gene were correlated with the expression levels of EGFP protein in polyclonal CHO cells. However, the heterogeneity of expression in monoclonal CHO cells was unaffected by transgene copy number. CONCLUSIONS: The findings may aid in the potential application of TOP1 MAR in expression enhancement of recombinant proteins in mammalian cells.
Assuntos
Células CHO , Engenharia Celular/métodos , DNA Topoisomerases Tipo I/genética , Expressão Gênica , Proteínas de Fluorescência Verde/biossíntese , Regiões de Interação com a Matriz , Proteínas Recombinantes/biossíntese , Animais , Cricetulus , Proteínas de Fluorescência Verde/genética , Humanos , Proteínas Recombinantes/genéticaRESUMO
CHO cells are the preferred host for the production of complex pharmaceutical proteins in the biopharmaceutical industry, and genome engineering of CHO cells would benefit product yield and stability. Here, we demonstrated the efficacy of a Dnmt3a-deficient CHO cell line created by CRISPR/Cas9 genome editing technology through gene disruptions in Dnmt3a, which encode the proteins involved in DNA methyltransferases. The transgenes, which were driven by the 2 commonly used CMV and EF1α promoters, were evaluated for their expression level and stability. The methylation levels of CpG sites in the promoter regions and the global DNA were compared in the transfected cells. The Dnmt3a-deficent CHO cell line based on Dnmt3a KO displayed an enhanced long-term stability of transgene expression under the control of the CMV promoter in transfected cells in over 60 passages. Under the CMV promoter, the Dnmt3a-deficent cell line with a high transgene expression displayed a low methylation rate in the promoter region and global DNA. Under the EF1α promoter, the Dnmt3a-deficient and normal cell lines with low transgene expression exhibited high DNA methylation rates. These findings provide insight into cell line modification and design for improved recombinant protein production in CHO and other mammalian cells.
Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , DNA (Citosina-5-)-Metiltransferases/genética , Edição de Genes/métodos , RNA Guia de Cinetoplastídeos/genética , Transgenes , Animais , Sequência de Bases , Células CHO , Proteína 9 Associada à CRISPR/metabolismo , Ilhas de CpG , Cricetulus , Citomegalovirus/genética , Citomegalovirus/metabolismo , DNA (Citosina-5-)-Metiltransferases/deficiência , Metilação de DNA , Expressão Gênica , Técnicas de Inativação de Genes , Regiões Promotoras Genéticas , RNA Guia de Cinetoplastídeos/metabolismoRESUMO
Chinese hamster ovary (CHO) cells have become the most widely utilized mammalian cell line for the production of recombinant proteins. However, the product yield and transgene instability need to be further increased and solved. In this study, we investigated the effect of five different introns on transgene expression in CHO cells. hCMV intron A, adenovirus tripartite leader sequence intron, SV40 intron, Chinese hamster EF-1alpha gene intron 1 and intervening sequence intron were cloned downstream of the eGFP expression cassette in a eukaryotic vector, which was then transfected into CHO cells. qRT-PCR and flow cytometry were used to explore eGFP expression levels. And gene copy number was also detected by qPCR, respectively. Furthermore, the erythropoietin (EPO) protein was used to test the selected more strong intron. The results showed that SV40 intron exhibited the highest transgene expression level among the five compared intron elements under transient and stable transfections. In addition, the SV40 intron element can increase the ratio of positive colonies and decrease the coefficient of variation in transgene expression level. Moreover, the transgene expression level was not related to the gene copy number in stable transfected CHO cells. Also, the SV40 intron induced higher level of EPO expression than IVS intron in transfected CHO cell. In conclusion, SV40 intron is a potent strong intron element that increases transgene expression, which can readily be used to more efficient transgenic protein production in CHO cells.
Assuntos
Íntrons/genética , Vírus 40 dos Símios/genética , Transfecção/métodos , Transgenes , Animais , Células CHO , Cricetinae , Cricetulus , Eritropoetina/metabolismo , Dosagem de Genes , Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Proteínas Recombinantes/metabolismoRESUMO
Hard carbon is considered as one of the most promising anodes in sodium-ion batteries due to its high capacity, low cost, and abundant resources. However, the available capacity and low initial Coulombic efficiency (ICE) limits the practical application of hard carbon anode. This issue results from the unclear understanding of the Na+ storage mechanism in hard carbon. In this work, a series of hard carbons with different microstructures are synthesized through an "up to down" approach by using a simple ball-milling method to illustrate the sodium-ion storage mechanism. The results demonstrate that ball-milled hard carbon with more defects and smaller microcrystalline size shows less low-potential-plateau capacity and lower ICE, which provides further evidence to the "adsorption-insertion" mechanism. This work might give a new perspective to design hard carbon material with a proper structure for efficient sodium-ion storage to develop high-performance sodium-ion batteries.
RESUMO
A chimeric DNA fragment containing an interferon-beta matrix attachment region (MAR) and an immunoglobulin MAR (PSAR2) was synthesized. PSAR2 was cloned into the upstream or downstream region of an enhanced green fluorescent protein (eGFP) expression cassette in a eukaryotic vector, which was then transfected into CHO cells. The results showed that PSAR2 did not effectively increase transgene expression when it was cloned into the upstream region of the eGFP expression cassette. However, when inserted downstream of the eGFP expression cassette, PSAR2-enhanced transient transgene expression and significantly increased the numbers of stably transfected cells compared with the control vector. Additionally, PSAR2 significantly increased eGFP copy numbers as compared with the control vector. PSAR2 could significantly enhance transgene expression in CHO cells according to the position in the vector and increased transgene copy numbers. We found a short chimeric sequence harboring two MARs effectively increased transgene expression in CHO cells.
Assuntos
Engenharia Genética/métodos , Imunoglobulinas/genética , Regiões de Interação com a Matriz/genética , Transgenes/genética , Animais , Células CHO , Cricetinae , Cricetulus , Proteínas de Fluorescência Verde/genética , Plasmídeos/genéticaRESUMO
Nitrogen (N) to phosphorus (P) allocation in plant organs is of particular interest, as both elements are important to regulate plant growth. We analyzed the scaling relationship of N and P in leaves, stems and fine roots of 224 plant species along an altitudinal transect (500-2,300 m) on the northern slope of Changbai Mountain, China. We tested whether the scaling relationships of N and P were conserved in response to environmental variations. We found that the N and P concentrations of the leaves, stems and fine roots decreased, whereas the N:P ratios increased with increasing altitude. Allometric scaling relationships of N and P were found in the leaves, stems and fine roots, with allometric exponents of 0.78, 0.71 and 0.87, respectively. An invariant allometric scaling of N and P in the leaves, stems and fine roots was detected for woody plants along the altitudinal gradient. These results may advance our understanding of plant responses to climate change, and provide a basis for practical implication of various ecological models.
Assuntos
Altitude , Nitrogênio/metabolismo , Fósforo/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Caules de Planta/metabolismo , Madeira/metabolismo , China , Modelos Lineares , Especificidade da EspécieRESUMO
Dunaliella salina, a single-celled marine alga with extreme salt tolerance, is an important model organism for studying fundamental extremophile survival mechanisms and their potential practical applications. In this study, two-dimensional differential in-gel electrophoresis (2D-DIGE) was used to investigate the expression of halotolerant proteins under high (3 M NaCl) and low (0.75 M NaCl) salt concentrations. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) and bioinformatics were used to identify and characterize the differences among proteins. 2D-DIGE analysis revealed 141 protein spots that were significantly differentially expressed between the two salinities. Twenty-four differentially expressed protein spots were successfully identified by MALDI-TOF/TOF MS, including proteins in the following important categories: molecular chaperones, proteins involved in photosynthesis, proteins involved in respiration and proteins involved in amino acid synthesis. Expression levels of these proteins changed in response to the stress conditions, which suggests that they may be involved in the maintenance of intracellular osmotic pressure, cellular stress responses, physiological changes in metabolism, continuation of photosynthetic activity and other aspects of salt stress. The findings of this study enhance our understanding of the function and mechanisms of various proteins in salt stress.
RESUMO
Glaucocalyxin H (GLH) is a new compound isolated from a traditional Chinese medical herb Isodon japonica var. glaucocalyx which has been used for folk medicine. This study was carried out for the first time to investigate the potential role of GLH in anti-hepatoma activity and underlying mechanisms in it. GLH could inhibit the growth of tumor in mice and induce HepG2 cells to death as assessed by the tumor reduction assay, toxic assay, morphological change, and survival rate assay. Many antitumor drugs originated from plants could inhibit the growth of tumor by inducing cells to apoptosis. The morphological changes of HepG2 cells treated with different concentrations of GLH under fluorescence and electron microscope and apoptotic rates were detected to verify its effect on apoptosis. As shown in the study, GLH could induce HepG2 cells to apoptosis in a dose-dependent manner. Bcl2 and Bax proteins played important roles in apoptosis and the disequilibrium between Bcl2 and Bax might result in apoptosis. The expression of Bax protein was upregulated and Bcl2 protein was downregulated in HepG2 cells treated with GLH assessed by Western blotting, and they were in a dose-dependent manner. Taken together, GLH can inhibit the growth of hepatoma cells in vivo and in vitro by inducing cell apoptosis due to the decreased Bcl2 and increased Bax proteins suggesting that GLH could be a potential candidate as an anti-hepatoma agent for the therapeutic treatment of hepatoma.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Diterpenos do Tipo Caurano/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Medicina Tradicional Chinesa/métodos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismoRESUMO
Methylation-sensitive amplified polymorphism was used in this study to investigate epigenetic information of four tobacco cultivars: Yunyan 85, NC89, K326, and Yunyan 87. The DNA fragments with methylated information were cloned by reamplified PCR and sequenced. The results of Blast alignments showed that the genes with methylation information included chitinase, nitrate reductase, chloroplast DNA, mitochondrial DNA, ornithine decarboxylase, ribulose carboxylase, and promoter sequences. Homologous comparison in three cloned gene sequences (nitrate reductase, ornithine decarboxylase, and ribulose decarboxylase) indicated that geographic factors had significant influence on the whole genome methylation. Introns also contained different information in different tobacco cultivars. These findings suggest that synthetic mechanisms for tobacco aromatic components could be affected by different environmental factors leading to variation of noncoding regions in the genome, which finally results in different fragrance and taste in different tobacco cultivars.
Assuntos
Metilação de DNA , Genes de Plantas , Nicotiana/genética , Marcadores Genéticos , Íntrons , Polimorfismo Genético , Análise de Sequência de DNARESUMO
River water quality is closely related to the major ion sources and hydrological conditions. However, there is a limited cognition about the geochemical sources and the seasonal variations of major ions. Thus, in this study, a total of 90 water samples were collected from the Longjiang River and its three tributaries in the dry and wet seasons. The samples were analyzed, including major ion concentrations and physicochemical parameters. Statistical analysis, such as correlation analysis and principal component analysis (PCA), was employed to investigate the spatial and seasonal variations in major ion composition and their respective sources. Our study revealed that the predominant major ions in the studied samples are Ca2+, Mg2+, HCO - 3, and SO2 - 4. Most of ions exhibited notable spatial disparities attributable to variations in geological settings and human activities. Regions characterized by igneous rock outcrops tend to exhibit higher levels of K+ and Na+, while areas with higher population densities in the middle and downstream segments show elevated concentrations of Cl-, NO - 3, SO2 - 4, Na+, and K+. The observed peak SO2 - 4 levels may be attributed to active mining operations. Most parameters displayed higher values in flood season than those in dry season due to dilution effects. Stoichiometric analysis indicated that carbonate weathering inputs contribute to over 85% of the mean total cation concentrations in the water, followed by contributions from silicates, atmospheric deposition, and anthropogenic inputs. On the whole, although the water quality remains non-polluted and is suitable for drinking and irrigation purposes, the enrichment of SO2 - 4 and NO - 3 may contribute to water eutrophication. Caution is warranted during the dry season due to reduced water flow resulting from dam interceptions and limited dilution capacity, potentially leading to elevated pollutant concentrations. Taken together, our results provided a scientific basis for water quality managements of monsoon rivers.