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1.
Biomolecules ; 14(6)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38927010

RESUMO

Nuclear hormone receptors exist in dynamic equilibrium between transcriptionally active and inactive complexes dependent on interactions with ligands, proteins, and chromatin. The present studies examined the hypothesis that endogenous ligands activate peroxisome proliferator-activated receptor-ß/δ (PPARß/δ) in keratinocytes. The phorbol ester treatment or HRAS infection of primary keratinocytes increased fatty acids that were associated with enhanced PPARß/δ activity. Fatty acids caused PPARß/δ-dependent increases in chromatin occupancy and the expression of angiopoietin-like protein 4 (Angptl4) mRNA. Analyses demonstrated that stearoyl Co-A desaturase 1 (Scd1) mediates an increase in intracellular monounsaturated fatty acids in keratinocytes that act as PPARß/δ ligands. The activation of PPARß/δ with palmitoleic or oleic acid causes arrest at the G2/M phase of the cell cycle of HRAS-expressing keratinocytes that is not found in similarly treated HRAS-expressing Pparb/d-null keratinocytes. HRAS-expressing Scd1-null mouse keratinocytes exhibit enhanced cell proliferation, an effect that is mitigated by treatment with palmitoleic or oleic acid. Consistent with these findings, the ligand activation of PPARß/δ with GW0742 or oleic acid prevented UVB-induced non-melanoma skin carcinogenesis, an effect that required PPARß/δ. The results from these studies demonstrate that PPARß/δ has endogenous roles in keratinocytes and can be activated by lipids found in diet and cellular components.


Assuntos
Queratinócitos , PPAR delta , PPAR beta , Estearoil-CoA Dessaturase , Queratinócitos/metabolismo , Queratinócitos/efeitos dos fármacos , PPAR beta/metabolismo , PPAR beta/genética , Animais , Camundongos , Estearoil-CoA Dessaturase/metabolismo , Estearoil-CoA Dessaturase/genética , PPAR delta/metabolismo , PPAR delta/genética , Ácidos Graxos/metabolismo , Proteína 4 Semelhante a Angiopoietina/metabolismo , Proteína 4 Semelhante a Angiopoietina/genética , Humanos , Ácido Oleico/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Ácidos Graxos Monoinsaturados/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
2.
Radiother Oncol ; 197: 110328, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38761884

RESUMO

BACKGROUND AND PURPOSE: Adjuvant treatments are valuable to decrease the recurrence rate and improve survival for early-stage cervical cancer patients (ESCC), Therefore, recurrence risk evaluation is critical for the choice of postoperative treatment. A magnetic resonance imaging (MRI) based radiomics nomogram integrating postoperative adjuvant treatments was constructed and validated externally to improve the recurrence risk prediction for ESCC. MATERIAL AND METHODS: 212 ESCC patients underwent surgery and adjuvant treatments from three centers were enrolled and divided into the training, internal validation, and external validation cohorts. Their clinical data, pretreatment T2-weighted images (T2WI) were retrieved and analyzed. Radiomics models were constructed using machine learning methods with features extracted and screen from sagittal and axial T2WI. A nomogram for recurrence prediction was build and evaluated using multivariable logistic regression analysis integrating radiomic signature and adjuvant treatments. RESULTS: A total of 8 radiomic features were screened out of 1020 extracted features. The extreme gradient boosting (XGboost) model based on MRI radiomic features performed best in recurrence prediction with an area under curve (AUC) of 0.833, 0.822 in the internal and external validation cohorts, respectively. The nomogram integrating radiomic signature and clinical factors achieved an AUC of 0.806, 0.718 in the internal and external validation cohorts, respectively, for recurrence risk prediction for ESCC. CONCLUSION: In this study, the nomogram integrating T2WI radiomic signature and clinical factors is valuable to predict the recurrence risk, thereby allowing timely planning for effective treatments for ESCC with high risk of recurrence.

3.
Skin Res Technol ; 30(4): e13698, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634154

RESUMO

BACKGROUND: Dermoscopy is a common method of scalp psoriasis diagnosis, and several artificial intelligence techniques have been used to assist dermoscopy in the diagnosis of nail fungus disease, the most commonly used being the convolutional neural network algorithm; however, convolutional neural networks are only the most basic algorithm, and the use of object detection algorithms to assist dermoscopy in the diagnosis of scalp psoriasis has not been reported. OBJECTIVES: Establishment of a dermoscopic modality diagnostic framework for scalp psoriasis based on object detection technology and image enhancement to improve diagnostic efficiency and accuracy. METHODS: We analyzed the dermoscopic patterns of scalp psoriasis diagnosed at 72nd Group army hospital of PLA from January 1, 2020 to December 31, 2021, and selected scalp seborrheic dermatitis as a control group. Based on dermoscopic images and major dermoscopic patterns of scalp psoriasis and scalp seborrheic dermatitis, we investigated a multi-network fusion object detection framework based on the object detection technique Faster R-CNN and the image enhancement technique contrast limited adaptive histogram equalization (CLAHE), for assisting in the diagnosis of scalp psoriasis and scalp seborrheic dermatitis, as well as to differentiate the major dermoscopic patterns of the two diseases. The diagnostic performance of the multi-network fusion object detection framework was compared with that between dermatologists. RESULTS: A total of 1876 dermoscopic images were collected, including 1218 for scalp psoriasis versus 658 for scalp seborrheic dermatitis. Based on these images, training and testing are performed using a multi-network fusion object detection framework. The results showed that the test accuracy, specificity, sensitivity, and Youden index for the diagnosis of scalp psoriasis was: 91.0%, 89.5%, 91.0%, and 0.805, and for the main dermoscopic patterns of scalp psoriasis and scalp seborrheic dermatitis, the diagnostic results were: 89.9%, 97.7%, 89.9%, and 0.876. Comparing the diagnostic results with those of five dermatologists, the fusion framework performs better than the dermatologists' diagnoses. CONCLUSIONS: Studies have shown some differences in dermoscopic patterns between scalp psoriasis and scalp seborrheic dermatitis. The proposed multi-network fusion object detection framework has higher diagnostic performance for scalp psoriasis than for dermatologists.


Assuntos
Dermatite Seborreica , Psoríase , Neoplasias Cutâneas , Humanos , Couro Cabeludo , Inteligência Artificial , Redes Neurais de Computação , Dermoscopia/métodos , Neoplasias Cutâneas/diagnóstico
4.
Plant Biotechnol J ; 22(6): 1703-1723, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319003

RESUMO

It is well known that calcium, ethylene and abscisic acid (ABA) can regulate fruit ripening, however, their interaction in the regulation of fruit ripening has not yet been fully clarified. The present study found that the expression of the papaya calcium sensor CpCML15 was strongly linked to fruit ripening. CpCML15 could bind Ca2+ and served as a true calcium sensor. CpCML15 interacted with CpPP2C46 and CpPP2C65, the candidate components of the ABA signalling pathways. CpPP2C46/65 expression was also related to fruit ripening and regulated by ethylene. CpCML15 was located in the nucleus and CpPP2C46/65 were located in both the nucleus and membrane. The interaction between CpCML15 and CpPP2C46/65 was calcium dependent and further repressed the activity of CpPP2C46/65 in vitro. The transient overexpression of CpCML15 and CpPP2C46/65 in papaya promoted fruit ripening and gene expression related to ripening. The reduced expression of CpCML15 and CpPP2C46/65 by virus-induced gene silencing delayed fruit colouring and softening and repressed the expression of genes related to ethylene signalling and softening. Moreover, ectopic overexpression of CpCML15 in tomato fruit also promoted fruit softening and ripening by increasing ethylene production and enhancing gene expression related to ripening. Additionally, CpPP2C46 interacted with CpABI5, and CpPP2C65 interacted with CpERF003-like, two transcriptional factors in ABA and ethylene signalling pathways that are closely related to fruit ripening. Taken together, our results showed that CpCML15 and CpPP2Cs positively regulated fruit ripening, and their interaction integrated the cross-talk of calcium, ABA and ethylene signals in fruit ripening through the CpCML15-CpPP2Cs-CpABI5/CpERF003-like pathway.


Assuntos
Ácido Abscísico , Cálcio , Carica , Etilenos , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Transdução de Sinais , Ácido Abscísico/metabolismo , Etilenos/metabolismo , Carica/metabolismo , Carica/genética , Carica/crescimento & desenvolvimento , Cálcio/metabolismo , Frutas/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Calmodulina/metabolismo , Calmodulina/genética , Reguladores de Crescimento de Plantas/metabolismo
5.
Genes (Basel) ; 14(9)2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37761824

RESUMO

Flavonoids have anti-inflammatory, antioxidative, and anticarcinogenic effects. Breeding rice varieties rich in flavonoids can prevent chronic diseases such as cancer and cardio-cerebrovascular diseases. However, most of the genes reported are known to regulate flavonoid content in leaves or seedlings. To further elucidate the genetic basis of flavonoid content in rice grains and identify germplasm rich in flavonoids in grains, a set of rice core collections containing 633 accessions from 32 countries was used to determine total flavonoid content (TFC) in brown rice. We identified ten excellent germplasms with TFC exceeding 300 mg/100 g. Using a compressed mixed linear model, a total of 53 quantitative trait loci (QTLs) were detected through a genome-wide association study (GWAS). By combining linkage disequilibrium (LD) analysis, location of significant single nucleotide polymorphisms (SNPs), gene expression, and haplotype analysis, eight candidate genes were identified from two important QTLs (qTFC1-6 and qTFC9-7), among which LOC_Os01g59440 and LOC_Os09g24260 are the most likely candidate genes. We also analyzed the geographic distribution and breeding utilization of favorable haplotypes of the two genes. Our findings provide insights into the genetic basis of TFC in brown rice and could facilitate the breeding of flavonoid-rich varieties, which may be a prevention and adjuvant treatment for cancer and cardio-cerebrovascular diseases.


Assuntos
Estudo de Associação Genômica Ampla , Oryza , Oryza/genética , Melhoramento Vegetal , Antioxidantes , Flavonoides/genética
6.
Metabolites ; 13(8)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37623879

RESUMO

Long-term ligand activation of PPARα in mice causes hepatocarcinogenesis through a mechanism that requires functional PPARα. However, hepatocarcinogenesis is diminished in both Ppara-null and PPARA-humanized mice, yet both lines develop age-related liver cancer independently of treatment with a PPARα agonist. Since PPARα is a master regulator of liver lipid metabolism in the liver, lipidomic analyses were carried out in wild-type, Ppara-null, and PPARA-humanized mice treated with and without the potent agonist GW7647. The levels of hepatic linoleic acid in Ppara-null and PPARA-humanized mice were markedly higher compared to wild-type controls, along with overall fatty liver. The number of liver CD4+ T cells was also lower in Ppara-null and PPARA-humanized mice and was negatively correlated with the elevated linoleic acid. Moreover, more senescent hepatocytes and lower serum TNFα and IFNγ levels were observed in Ppara-null and PPARA-humanized mice with age. These studies suggest a new role for PPARα in age-associated hepatocarcinogenesis due to altered lipid metabolism in Ppara-null and PPARA-humanized mice and the accumulation of linoleic acid as part of an overall fatty liver that is associated with loss of CD4+ T cells in the liver in both transgenic models. Since fatty liver is a known causal risk factor for liver cancer, Ppara-null and PPARA-humanized mice are valuable models for examining the mechanisms of PPARα and age-dependent hepatocarcinogenesis.

7.
Sci Total Environ ; 859(Pt 1): 160135, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36375547

RESUMO

Rapid global industrialization has resulted in widespread cadmium contamination in agricultural soils and products. A considerable proportion of rice consumers are exposed to Cd levels above the provisional safe intake limit, raising widespread environmental concerns on risk management. Therefore, a generalized approach is urgently needed to enable correct evaluation and early warning of cadmium contaminants in rice products. Combining big data and computer science together, this study developed a system named "SMART Cd Early Warning", which integrated 4 modules including genotype-to-phenotype (G2P) modelling, high-throughput sequencing, G2P prediction and rice Cd contamination risk assessment, for rice cadmium accumulation early warning. This system can rapidly assess the risk of rice cadmium accumulation by genotyping leaves at seeding stage. The parameters including statistical methods, population size, training population-testing population ratio, SNP density were assessed to ensure G2P model exhibited superior performance in terms of prediction precision (up to 0.76 ± 0.003) and computing efficiency (within 2 h). In field trials of cadmium-contaminated farmlands in Wenling and Fuyang city, Zhejiang Province, "SMART Cd Early Warning" exhibited superior capability for identification risk rice varieties, suggesting a potential of "SMART Cd Early-Warning system" in OsGCd risk assessment and early warning in the age of smart.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Poluentes do Solo/análise , Solo , Medição de Risco
8.
Foods ; 11(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36496689

RESUMO

Ethylene response factors (ERFs) are one of largest plant-specific transcription factor families involved in fruit ripening. However, the regulatory mechanism by which ERFs modulate fruit yellowing and softening remains unknown in banana. We previously found that the transcription of MaERF012 was closely related to 'Fenjiao' banana fruit ripening. Herein, we found that MaERF012 was differentially expressed in the fruit pulp and peel and was closely related to fruit ripening. MaERF012 activated the promoter activity of one chlorophyll degradation gene (MaSGR1), two starch degradation genes (MaGWD1 and MaAMY3), and three cell wall degradation genes (MaPL8, MaEXP-A8, and MaXYL23-like), which were tested by EMSA, Y1H, and DLR. Transient overexpression of MaERF012 accelerates fruit ripening by promoting fruit yellowing and softening by up-regulating the transcription of chlorophyll, starch, and cell wall degradation genes. Over-expression of MaERF012 alters the transcriptome profiles of the fruit peel and pulp, and the differentially expressed genes were mainly enriched in starch and sucrose metabolism, plant hormone signal transduction, biosynthesis of secondary metabolism, and fructose and mannose metabolism. Overall, the data showed that MaERF012 acts as a transcriptional activator by regulating fruit ripening by activating the transcription of chlorophyll, starch, and cell wall degradation genes.

9.
Antioxidants (Basel) ; 11(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36290729

RESUMO

Deoxynivalenol (DON), as a secondary metabolite of fungi, is continually detected in livestock feed and has a high risk to animals and humans. Moreover, pigs are very sensitive to DON. Recently, the role of histone modification has drawn people's attention; however, few studies have elucidated how histone modification participates in the cytotoxicity or genotoxicity induced by mycotoxins. In this study, we used intestinal porcine epithelial cells (IPEC-J2 cells) as a model to DON exposure in vitro. Mixed lineage leukemia 1 (MLL1) regulates gene expression by exerting the role of methyltransferase. Our studies demonstrated that H3K4me3 enrichment was enhanced and MLL1 was highly upregulated upon 1 µg/mL DON exposure in IPEC-J2 cells. We found that the silencing of MLL1 resulted in increasing the apoptosis rate, arresting the cell cycle, and activating the mitogen-activated protein kinases (MAPKs) pathway. An RNA-sequencing analysis proved that differentially expressed genes (DEGs) were enriched in the cell cycle, apoptosis, and tumor necrosis factor (TNF) signaling pathway between the knockdown of MLL1 and negative control groups, which were associated with cytotoxicity induced by DON. In summary, these current results might provide new insight into how MLL1 regulates cytotoxic effects induced by DON via an epigenetic mechanism.

10.
Antioxidants (Basel) ; 11(5)2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35624668

RESUMO

Papaya fruit is widely grown in tropical regions because of its sweet taste, vibrant color, and the huge number of health benefits it provides. Melatonin is an essential hormone that governs many plants' biological processes. In the current study, the impact of melatonin on fruit ripening and deterioration in postharvest papaya fruit was explored. An optimum melatonin dose (400 µmol L-1, 2 h) was found to be effective in delaying fruit softening and reducing anthracnose incidence. Melatonin enhanced antioxidant activity and decreased fruit oxidative injury by lowering superoxide anion, hydrogen peroxide, and malondialdehyde content by enhancing the enzymatic and non-enzymatic antioxidants, and by improving the antioxidant capacity of papaya fruit. Melatonin increased catalase, ascorbate peroxidase, NADH oxidase, glutathione reductase, polyphenol oxidase, superoxide dismutase, and peroxidase activity, as well as induced total phenol, total flavonoid, and ascorbic acid accumulation. Melatonin also enhanced the activity of defense-related enzymes, such as chitinase, 4-coumaric acid-CoA-ligase, and phenylalanine ammonia lyase, while it repressed lipid metabolism. Additionally, melatonin inhibited the development of anthracnose in vitro and in vivo. These findings suggest that exogenous melatonin application improves papaya fruit quality by boosting antioxidant and defense-related mechanisms.

11.
Front Plant Sci ; 13: 805247, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498718

RESUMO

Iron (Fe) is a limiting factor in crop growth and nutritional quality because of its low solubility. However, the current understanding of how major crops respond to Fe deficiency and the genetic basis remains limited. In the present study, Fe-efficient inbred line Ye478 and Fe-inefficient inbred line Wu312 and their recombinant inbred line (RIL) population were utilized to reveal the physiological and genetic responses of maize to low Fe stress. Compared with the Fe-sufficient conditions (+Fe: 200 µM), Fe-deficient supply (-Fe: 30 µM) significantly reduced shoot and root dry weights, leaf SPAD of Fe-efficient inbred line Ye478 by 31.4, 31.8, and 46.0%, respectively; decreased Fe-inefficient inbred line Wu312 by 72.0, 45.1, and 84.1%, respectively. Under Fe deficiency, compared with the supply of calcium nitrate (N1), supplying ammonium nitrate (N2) significantly increased the shoot and root dry weights of Wu312 by 37.5 and 51.6%, respectively; and enhanced Ye478 by 23.9 and 45.1%, respectively. Compared with N1, N2 resulted in a 70.0% decrease of the root Fe concentration for Wu312 in the -Fe treatment, N2 treatment reduced the root Fe concentration of Ye478 by 55.8% in the -Fe treatment. These findings indicated that, compared with only supplying nitrate nitrogen, combined supply of ammonium nitrogen and nitrate nitrogen not only contributed to better growth in maize but also significantly reduced Fe concentration in roots. In linkage analysis, ten quantitative trait loci (QTLs) associated with Fe deficiency tolerance were detected, explaining 6.2-12.0% of phenotypic variation. Candidate genes considered to be associated with the mechanisms underlying Fe deficiency tolerance were identified within a single locus or QTL co-localization, including ZmYS3, ZmPYE, ZmEIL3, ZmMYB153, ZmILR3 and ZmNAS4, which may form a sophisticated network to regulate the uptake, transport and redistribution of Fe. Furthermore, ZmYS3 was highly induced by Fe deficiency in the roots; ZmPYE and ZmEIL3, which may be involved in Fe homeostasis in strategy I plants, were significantly upregulated in the shoots and roots under low Fe stress; ZmMYB153 was Fe-deficiency inducible in the shoots. Our findings will provide a comprehensive insight into the physiological and genetic basis of Fe deficiency tolerance.

12.
Sci Rep ; 11(1): 18173, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518559

RESUMO

Itaconic acid is produced by immune responsive gene 1 (IRG1)-coded enzyme in activated macrophages and known to play an important role in metabolism and immunity. In this study, mechanism of itaconic acid functioning as an anti-inflammatory metabolite was investigated with molecular biology and immunology techniques, by employing IRG1-null (prepared with CRISPR) and wild-type macrophages. Experimental results showed that itaconic acid significantly promoted the pentose phosphate pathway (PPP), which subsequently led to significantly higher NADPH oxidase activity and more reactive oxygen species (ROS) production. ROS production increased the expression of anti-inflammatory gene A20, which in turn decreased the production of inflammatory cytokines IL-6, IL-1ß and TNF-α. NF-κB, which can up-regulate A20, was also vital in controlling IRG1 and itaconic acid involved immune-modulatory responses in LPS-stimulated macrophage in this study. In addition, itaconic acid inhibited the growth of Salmonella typhimurium in cell through increasing ROS production from NADPH oxidase and the hatching of Schistosoma japonicum eggs in vitro. In short, this study revealed an alternative mechanism by which itaconic acid acts as an anti-inflammatory metabolite and confirmed the inhibition of bacterial pathogens with itaconic acid via ROS in cell. These findings provide the basic knowledge for future biological applications of itaconic acid in anti-inflammation and related pathogens control.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Via de Pentose Fosfato/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Succinatos/farmacologia , Animais , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Óvulo/efeitos dos fármacos , Células RAW 264.7 , Salmonella typhimurium/crescimento & desenvolvimento , Schistosoma japonicum/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
13.
Toxicol Sci ; 183(1): 70-80, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34081128

RESUMO

Ppara-null and PPARA-humanized mice are refractory to hepatocarcinogenesis caused by the peroxisome proliferator-activated receptor-α (PPARα) agonist Wy-14,643. However, the duration of these earlier studies was limited to approximately 1 year of treatment, and the ligand used has a higher affinity for the mouse PPARα compared to the human PPARα. Thus, the present study examined the effect of long-term administration of a potent, high-affinity human PPARα agonist (GW7647) on hepatocarcinogenesis in wild-type, Ppara-null, or PPARA-humanized mice. In wild-type mice, GW7647 caused hepatic expression of known PPARα target genes, hepatomegaly, hepatic MYC expression, hepatic cytotoxicity, and a high incidence of hepatocarcinogenesis. By contrast, these effects were essentially absent in Ppara-null mice or diminished in PPARA-humanized mice, although hepatocarcinogenesis was observed in both genotypes. Enhanced fatty change (steatosis) was also observed in both Ppara-null and PPARA-humanized mice independent of GW7647. PPARA-humanized mice administered GW7647 also exhibited increased necrosis after 5 weeks of treatment. Results from these studies demonstrate that the mouse PPARα is required for hepatocarcinogenesis induced by GW7647 administered throughout adulthood. Results also indicate that a species difference exists between rodents and human PPARα in the response to ligand activation of PPARα. The hepatocarcinogenesis observed in control and treated Ppara-null mice is likely mediated in part by increased hepatic fatty change, whereas the hepatocarcinogenesis observed in PPARA-humanized mice may also be due to enhanced fatty change and cytotoxicity that could be influenced by the minimal activity of the human PPARα in this mouse line on downstream mouse PPARα target genes. The Ppara-null and PPARA-humanized mouse models are valuable tools for examining the mechanisms of PPARα-induced hepatocarcinogenesis, but the background level of liver cancer must be controlled for in the design and interpretation of studies that use these mice.


Assuntos
Fígado Gorduroso , Neoplasias Hepáticas , Adulto , Animais , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Camundongos , Camundongos Knockout , PPAR alfa/genética
14.
Toxicol Sci ; 183(1): 81-92, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34081146

RESUMO

Evidence suggests that species differences exist between rodents and humans in their biological responses to ligand activation of PPARα. Moreover, neonatal/postnatal rodents may be more sensitive to the effects of activating PPARα. Thus, the present studies examined the effects of chronic ligand activation of PPARα initiated during early neonatal development and continued into adulthood on hepatocarcinogenesis in mice. Wild-type, Ppara-null, or PPARA-humanized mice were administered a potent, high-affinity human PPARα agonist GW7647, and cohorts of mice were examined over time. Activation of PPARα with GW7647 increased expression of known PPARα target genes in liver and was associated with hepatomegaly, increased hepatic cytotoxicity and necrosis, increased expression of hepatic MYC, and a high incidence of hepatocarcinogenesis in wild-type mice. These effects did not occur or were largely diminished in Ppara-null and PPARA-humanized mice, although background levels of hepatocarcinogenesis were also noted in both Ppara-null and PPARA-humanized mice. More fatty change (steatosis) was also observed in both Ppara-null and PPARA-humanized mice independent of GW7647 administration. Results from these studies indicate that the mouse PPARα is required to mediate hepatocarcinogenesis induced by GW7647 in mice and that activation of the human PPARα with GW7647 in PPARA-humanized mice are diminished compared with wild-type mice. Ppara-null and PPARA-humanized mice are valuable tools for examining species differences in the mechanisms of PPARα-induced hepatocarcinogenesis, but background levels of liver cancer observed in aged Ppara-null and PPARA-humanized mice must be considered when interpreting results from studies that use these models. These results also demonstrate that early life exposure to a potent human PPARα agonist does not enhance sensitivity to hepatocarcinogenesis.


Assuntos
Fígado Gorduroso , Neoplasias Hepáticas , Adulto , Idoso , Animais , Feminino , Humanos , Fígado , Neoplasias Hepáticas/induzido quimicamente , Camundongos , Camundongos Knockout , PPAR alfa/genética , Gravidez , Especificidade da Espécie
16.
Nat Commun ; 10(1): 2562, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189898

RESUMO

Cadmium (Cd) accumulation in rice grain poses a serious threat to human health. While several transport systems have been reported, the complicity of rice Cd transport and accumulation indicates the necessity of identifying additional genes, especially those that are responsible for Cd accumulation divergence between indica and japonica rice subspecies. Here, we show that a gene, OsCd1, belonging to the major facilitator superfamily is involved in root Cd uptake and contributes to grain accumulation in rice. Natural variation in OsCd1 with a missense mutation Val449Asp is responsible for the divergence of rice grain Cd accumulation between indica and japonica. Near-isogenic line tests confirm that the indica variety carrying the japonica allele OsCd1V449 can reduce the grain Cd accumulation. Thus, the japonica allele OsCd1V449 may be useful for reducing grain Cd accumulation of indica rice cultivars through breeding.


Assuntos
Cádmio/metabolismo , Grão Comestível/metabolismo , Proteínas de Membrana/metabolismo , Oryza/metabolismo , Poluentes do Solo/metabolismo , Alelos , Asparagina/genética , Cádmio/análise , Membrana Celular/metabolismo , Grão Comestível/química , Humanos , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Oryza/química , Oryza/genética , Filogenia , Melhoramento Vegetal/métodos , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Poluentes do Solo/análise , Valina/genética
17.
Nanomedicine (Lond) ; 13(8): 913-928, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29527969

RESUMO

AIM: To evaluate the advantages of nanomaterial methoxy poly(ethylene glycol)-poly(lactide-co-glycolide) (mPEG-PLGA) encapsulated doxorubicin (D/DOX) and paclitaxel (T/TAX; mPEG-PLGA-DT) over free form of DOX and TAX (DOX/TAX). MATERIALS & METHODS: Metabonomics was conducted to characterize the systemic metabolic response of allograft breast cancer model mice to mPEG-PLGA-DT and DOX/TAX treatments. RESULTS: Breast tumor growth induced metabolic reprogram in serum and multiple organs. DOX/TAX treatment could ameliorate the elevated energy and nucleotides demands in some organs while mPEG-PLGA-DT treatment showed outstanding therapeutic outcomes in restoring the metabolic phenotypes of serum and kidney from tumor-bearing mice to the healthy state. CONCLUSION: This investigation proved the biological advantages of mPEG-PLGA-DT over DOX/TAX in molecular level through the comparison between their metabolic responses in vivo.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Neoplasias Mamárias Animais/tratamento farmacológico , Paclitaxel/administração & dosagem , Animais , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Rim/efeitos dos fármacos , Neoplasias Mamárias Animais/sangue , Neoplasias Mamárias Animais/diagnóstico por imagem , Neoplasias Mamárias Animais/patologia , Metabolômica , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Paclitaxel/química , Poliésteres/administração & dosagem , Poliésteres/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química
18.
J Radiat Res ; 59(2): 207-215, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415196

RESUMO

A multidimensional exploratory statistical method, canonical correlation analysis (CCA), was applied to evaluate the impact of complexity parameters on the plan quality and deliverability of volumetric-modulated arc therapy (VMAT) and to determine parameters in the generation of an ideal VMAT plan. Canonical correlations among complexity, quality and deliverability parameters of VMAT, as well as the contribution weights of different parameters were investigated with 71 two-arc VMAT nasopharyngeal cancer (NPC) patients, and further verified with 28 one-arc VMAT prostate cancer patients. The average MU and MU per control point (MU/CP) for two-arc VMAT plans were 702.6 ± 55.7 and 3.9 ± 0.3 versus 504.6 ± 99.2 and 5.6 ± 1.1 for one-arc VMAT plans, respectively. The individual volume-based 3D gamma passing rates of clinical target volume (γCTV) and planning target volume (γPTV) for NPC and prostate cancer patients were 85.7% ± 9.0% vs 92.6% ± 7.8%, and 88.0% ± 7.6% vs 91.2% ± 7.7%, respectively. Plan complexity parameters of NPC patients were correlated with plan quality (P = 0.047) and individual volume-based 3D gamma indices γ(IV) (P = 0.01), in which, MU/CP and segment area (SA) per control point (SA/CP) were weighted highly in correlation with γ(IV) , and SA/CP, percentage of CPs with SA < 5 × 5 cm2 (%SA < 5 × 5 cm2) and PTV volume were weighted highly in correlation with plan quality with coefficients of 0.98, 0.68 and -0.99, respectively. Further verification with one-arc VMAT plans demonstrated similar results. In conclusion, MU, SA-related parameters and PTV volume were found to have strong effects on the plan quality and deliverability.


Assuntos
Algoritmos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Masculino , Neoplasias Nasofaríngeas/radioterapia , Neoplasias da Próstata/radioterapia
19.
Radiat Oncol ; 11(1): 138, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27756417

RESUMO

OBJECTIVES: To explore the areas at highest risk for postoperative pancreatic cancer local recurrence according to the spatial location of local failures, with the aim to provide a precise target volume for pancreatic cancer adjuvant radiotherapy. METHODS: Patients with pancreatic cancer who had undergone surgery for the primary tumor in pancreas at our institution from January 2010 to August 2015 were retrospectively analyzed. All local recurrences were plotted on the computed tomography (CT) image of a representative patient according to their relative coordinates to superior mesenteric artery (SMA) or celiac axis (CA). Adjuvant radiation clinical target volume (CTV)-90 and CTV-80 were created to cover 90 % and 80 % plotted recurrences. This planning approach was applied in four simulated cases with comparison to the plan according to RTOG 0848 contouring consensus guidelines. Raystation v4.5.1.14 was used for analyzing high throughput physics data. RESULTS: Eighty-three patients with local recurrence were included from 305 postoperative pancreatic cancer patients who did not receive adjuvant radiotherapy. Thirty-one (37 %) patients did not have adjuvant therapy at all, 52 (63 %) patients undergone adjuvant chemotherapy alone. Spatial location of local failure was created. Most recurrences occurred near CA or SMA. CTV-90 was generated through expanding the combined SMA and CA contours by 30 mm right-lateral, 21 mm left-lateral, 20 mm anterior, 13 mm posterior, 10 mm superior, and 20 mm inferior. CTV-80, smaller in volume, was also created for simultaneous integrated boost. Through comparison and analysis of the simulated cases, the radiation volumes proposed were much smaller than those with RTOG 0848 contouring consensus guidelines (average volume: PTV-80 = 120 ml, PTV-90 = 220 ml, RTOG PTV = 490 ml). Accordingly, the organs at risk received less irradiation dose with the proposed CTV-90 and CTV-80. CONCLUSIONS: Smaller adjuvant radiotherapy CTVs targeting the high-risk local failure areas of postoperative pancreatic cancer were proposed, according to the three-dimensional spatial location of local recurrences. This may help to minimize radiation-related toxicities, achieve dose escalation, and finally reduce local recurrence.


Assuntos
Recidiva Local de Neoplasia/radioterapia , Neoplasias Pancreáticas/radioterapia , Planejamento da Radioterapia Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Neoplasias Pancreáticas/patologia , Período Pós-Operatório , Radioterapia Adjuvante , Estudos Retrospectivos
20.
J Agric Food Chem ; 64(7): 1494-502, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26871966

RESUMO

Benzothiadiazole (BTH) works as a plant activator. The effects of different BTH treatments and fungicides SPORGON on fruit ripening and disease incidence were investigated. The results showed that BTH treatment significantly delayed fruit ripening, maintained fruit firmness, color, and good fruit quality, and dramatically reduced the incidence of disease. BTH effectively inhibited the invasion and development of pathogenic bacteria and controlled the occurrence of disease. BTH treatment enhanced the activities of defense-related enzymes, including chitinase, phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase, increased the content of hydrogen peroxide and total antioxidant capacity, and reduced malondialdehyde content. Cellular structure analysis after inoculation confirmed that BTH treatment effectively maintained the cell structural integrity. SPORGON did not provide benefits for delaying fruit ripening or for the resistance system, while it can control the disease only during the earlier stage and not at later stages.


Assuntos
Colletotrichum/fisiologia , Frutas/crescimento & desenvolvimento , Musa/efeitos dos fármacos , Musa/imunologia , Tiadiazóis/farmacologia , Frutas/efeitos dos fármacos , Frutas/imunologia , Frutas/microbiologia , Fungicidas Industriais/farmacologia , Regulação da Expressão Gênica de Plantas , Musa/crescimento & desenvolvimento , Musa/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/imunologia
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