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1.
Toxicol Pathol ; : 192623319877154, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31581932

RESUMO

As a eusocial species, Apis mellifera, the European honey bee, is effectively a superorganism-a group of genetically related individuals functioning as a collective unit. Because the unit of selection is the colony and not the individual, standard methods for assessing toxicologic pathology can miss colony-level responses to stress. For over a decade, US populations of honeybees have experienced severe annual losses attributed to a variety of environmental stressors varying temporally and geographically; differentiating among those stressors is accordingly a high priority. Social interactions among individuals in this social species, however, mean that the "footprint" of stressors such as pesticides, phytochemicals, pathogens, and parasites may be most discernible in individuals that did not themselves directly encounter the stressor. For example, neurotoxic effects of pesticides on nurse bees may impair their behavioral responses to queen-destined larvae, which may then emerge as adults with altered anatomy or physiology. Similarly, pesticide-induced size alterations in nurse hypopharyngeal glands, which produce royal jelly, the exclusive food of larval and adult queens, may disproportionately affect the queen's (and thus colony) health. Thus, evaluating toxicologic pathology in the honeybee requires a new perspective and development of assays that preserve the social context that ultimately determines colony health.

2.
PLoS One ; 14(10): e0223356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31600253

RESUMO

'Huangguogan' (Citrus reticulata × C. sinensis) is a new cultivar of mandarin citrus in China, and the research on fertilization of 'Huangguogan' is very limited. In this study, the effect of N fertilization on 'Huangguogan' fruit quality was determined at ripening. Sugars (sucrose, fructose, and glucose), organic acids (pyruvic, oxalic, citric acid, etc.), and vitamin components were measured at six stages of fruit development, and eight enzymes related to the glycolytic and Krebs cycle were assessed. The 1.81 kg N y-1 treatment group showed the highest total soluble solids concentration and total soluble solids/titratable acidity ratio but the lowest titratable acidity (acid content) at ripening, while the N1 treatment (0 kg N y-1) showed the opposite trend. Sucrose and citric acid accumulated to the largest extent during fruit development. Sucrose and ascorbic acid content increased (8.46 to 50.97 mg g-1 and 8.16 to 27.39 mg g-1, respectively), while citric acid content decreased (90.81 to 0.02 mg g-1). Aconitase was the key enzyme responsible for the observed changes in citric acid. The N concentrations in ripening fruit ranged from 2.25% to 4.15%. Curve estimation and principal component analysis revealed that fruit N was positively correlated with the sugars and vitamin components and negatively correlated with the organic acids. The accumulation of these metabolites seemed closely related to the dynamic changes in fruit N concentration at the five N levels tested. In conclusion, we suggest that the 1.81 kg N y-1 treatment represents the most suitable N fertilizer treatment for 'Huangguogan' citrus fruit.

3.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3745-3748, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602948

RESUMO

A new isobenzofuranone derivative was isolated from Chaenomeles sinensis by using various chromatographic techniques,including silica gel,Sephadex LH-20,MCI-gel resin and RP-HPLC. This compound was determined as 2,2-dimethyl-5-( 2-oxopropyl)-2 H-furo[3,4-h]chromen-7( 9 H)-one( 1) by NMR,MS,IR and UV spectra,and was also evaluated for its antibacterial activity. The results showed that it showed prominent antibacterial activity with MIC90 value of( 53. 7±4. 5) mg·L-1 for methicillin resistant Staphylococcus aureus( MRSA) strain. This value is close to that of levofloxacin [with MIC90 value( 50. 2± 4. 2) mg·L-1].


Assuntos
Antibacterianos/farmacologia , Benzofuranos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Rosaceae/química , Antibacterianos/isolamento & purificação , Benzofuranos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
4.
Biosci Biotechnol Biochem ; 83(10): 1924-1936, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31244380

RESUMO

This study examined the physiological effects of different amounts of nitrogen (N) supplementation (0 to 2.72 kg/year) on the citrus cultivar Huangguogan (Citrus reticulata × Citrus sinensis). Root activity, chlorophyll content, and fruit quality were measured, and the activities of the antioxidant enzymes superoxide dismutase (SOD), guaiacol peroxidase (POD), and catalase (CAT), and the contents of malondialdehyde (MDA) and soluble protein in root, leaf, and fruit tissues were examined at different developmental stages. Root activity, chlorophyll content, fruit quality, antioxidant enzyme activity, MDA content, and soluble protein content increased in plants treated with an appropriate amount of N. Both excessive N and N deficiency decreased the content of MDA and the activities of antioxidant enzymes. Application of 1.36-1.81 kg N/year is suggested for citrus fertilization and the lower end of this range is recommended for minimizing environmental impact and production cost.

5.
PLoS One ; 14(5): e0216639, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31048916

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0213874.].

6.
PLoS One ; 14(3): e0213874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30897177

RESUMO

Nitrogen metabolism in citrus has received increased attention due to its effects on plant growth and productivity. However, little is known about the effects of nitrogen fertilization on nitrogen metabolism in young trees of citrus cultivar 'Huangguogan' (Citrus reticulata × Citrus sinensis). Here, genes encoding nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), glutamate dehydrogenase (GDH), and asparagine synthetase (AS), represented as HgNR, HgNiR, HgGS, HgGDH, and HgAS, respectively, were cloned from Huangguogan. Deduced protein sequences were analyzed and proteins were confirmed to be localized in their respective cellular organelles. Moreover, pot-cultured 'Huangguogan' seedlings were fertilized with 0 (N1), 1.36 (N2), 1.81 (N3), 2.26 (N4), or 2.72 (N5) kg N/year, for 12 months. Enzyme activity and enzyme-gene expression were studied in roots, leaves, and fruits at different stages. Finally, the effects of N application rate on root activity, leaf N, soluble protein, yield, and fruit quality at the ripening stage were measured. The results showed that: 1) HgNR, HgNiR, HgGDH, and HgAS gene products were found mainly in the cytoplasm and plasma membrane, while HgGS gene product was found mainly in cytoplasm and mitochondria. 2) Gene expression and enzyme activity differed among plant organs. As the root is in permanent direct contact with the soil we suggest that root gene expression and enzyme activity can be used as reference to determine N application rate. 3) Yield, fruit quality, enzyme activity, and enzyme-related gene expression were considerably lower at low than at high-N supply. However, they were all inhibited by excess nitrogen (i.e., 2.72 kg/year). Therefore, we recommend 1.81 kg N/year as the optimal N application rate for young 'Huangguogan' trees.

7.
Int J Mol Med ; 43(5): 2055-2063, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864739

RESUMO

Hydrogen sulfide (H2S) is an endogenous gaseous signaling molecule that plays important roles in the cardiovascular system. In our previous studies, we demonstrated that H2S regulates lipid metabolism. In the present study, we aimed to explore the mechanisms through which H2S regulates lipid metabolism in HepG2 cells in vitro. Treatment of the HepG2 cells with H2S inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) and increased the level of low­density lipoprotein receptor (LDLR) in a time­ and dose­dependent manner. The knockdown of PCSK9 by siRNA effectively increased the levels of LDLR and 1,1'­dioctadecyl­3,3,3',3'­tetramethyl­indocarbocyanine perchlorate­labeled LDL (DiI­LDL) uptake in the H2S­treated HepG2 cells. Furthermore, the phosphoinositide 3­kinase (PI3K)/protein kinase B (Akt)­sterol regulatory element binding proteins 2 (SREBP­2) signaling pathway was confirmed to be involved in H2S­regulated PCSK9 expression. Notably, the HepG2 cells were incubated with 30% serum and DiI­LDL for 24 h, and the results revealed that H2S increased lipid uptake, but caused no increase in lipid accumulation. On the whole, the findings of this study demonstrate that H2S is involved in the regulation of lipid metabolism in HepG2 cells through the regulation of the expression of PCSK9 via the PI3K/Akt­SREBP­2 signaling pathway. To the very best of our knowledge, this study is the first to report that H2S can regulate the expression of PCSK9.


Assuntos
Sulfeto de Hidrogênio/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Pró-Proteína Convertase 9/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Células Hep G2 , Humanos , Modelos Biológicos , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
Sci Rep ; 9(1): 1032, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30705367

RESUMO

PES1, a BRCT domain-containing protein, has been shown to play a role in modulating the balance and ratio between ERα and ERß protein, which is involved in the occurrence and development of breast and ovarian cancer. However, its role in connection with the balance and ratio between ERα and ERß protein in papillary thyroid cancer (PTC) remains unclear. Here, we found that ERα and ERß were co-expressed in human PTC tissues and cells. ERα promoted and ERß inhibited the proliferation, invasion and migration of PTC cells. PES1 modulated the balance between ERα and ERß by elevating the ERα protein level and simultaneously reducing the ERß protein level, then upregulating the ERα/ERß protein ratio and promoting the proliferation, invasion and migration of PTC cells. In PTC tissues, PES1 protein level was positively correlated with the ERα protein level and negatively correlated with the ERß protein level. The PES1 and ERα protein levels were gradually increased and the ERß protein level was decreased by degree in the occurrence and development of PTC. Increased PES1 and ERα protein levels and decreased ERß protein level were correlated with the aggressive behaviors of PTC patients such as large tumor size, extrathyroidal extension (ETE), lymph node metastasis (LNM), high BRAFV600E expression and high TNM stage. It is suggested that PES1 promotes the occurrence and development of PTC by elevating the ERα protein level and reducing the ERß protein level, and then upregulating the ERα/ERß protein ratio.

9.
PLoS One ; 13(11): e0206625, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383869

RESUMO

BACKGROUND: The presence of the neonicotinoid imidacloprid in nectar, honey, pollen, beebread and beeswax has been implicated in declines worldwide in the health of the western honey bee Apis mellifera. Certain phytochemicals, including quercetin and p-coumaric acid, are ubiquitous in the honey bee diet and are known to upregulate cytochrome P450 genes encoding enzymes that detoxify insecticides. Thus, the possibility exists that these dietary phytochemicals interact with ingested imidacloprid to ameliorate toxicity by enhancing its detoxification. APPROACH: Quercetin and p-coumaric acid were incorporated in a phytochemical-free artificial diet individually and together along with imidacloprid at a range of field-realistic concentrations. In acute toxicity bioassays, honey bee 24- and 48- hour imidacloprid LC50 values were determined in the presence of the phytochemicals. Additionally, chronic toxicity bioassays were conducted using varying concentrations of imidacloprid in diets with the phytochemicals to test impacts of phytochemicals on longevity. RESULTS: In acute toxicity bioassays, the phytochemicals had no effect on imidacloprid LC50 values. In chronic toxicity longevity bioassays, phytochemicals enhanced honey bee survival at low imidacloprid concentrations (15 and 45 ppb) but had a negative effect at higher concentrations (105 ppb and 135 ppb). p-Coumaric acid alone increased honey bee longevity at concentrations of 15 and 45 ppb imidacloprid (hazard ratio (HR): 0.83 and 0.70, respectively). Quercetin alone and in combination with p-coumaric acid similarly enhanced longevity at 45 ppb imidacloprid (HR:0.81 and HR:0.77, respectively). However, p-coumaric acid in combination with 105 ppb imidacloprid and quercetin in combination with 135 ppb imidacloprid increased honey bee HR by approximately 30% (HR:1.33 and HR:1.30, respectively). CONCLUSIONS: The biphasic concentration-dependent response of honey bees to imidacloprid in the presence of two ubiquitous dietary phytochemicals indicates that there are limits to the protective effects of the natural diet of honey bees against neonicotinoids based on their own inherent toxicity.

10.
Molecules ; 23(11)2018 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-30423891

RESUMO

Insulin injection relies on strict blood glucose monitoring. However, existing techniques and algorithms for blood glucose monitoring cannot be completed in a timely way. In this study, we have developed a new intelligent glucose-sensitive insulin delivery system to stabilize blood glucose levels in the body. This system does not require real-time detection of blood glucose. First, we successfully synthesized a nanoscale material called PAM-PAspPBA-b-PEG by using chemical methods. We then conducted TEM, DLS, and ¹H-NMR analyses to characterize the physicochemical properties, such as size, molecular composition, and configuration of the nanomaterial. We verified the glucose responsibility of the insulin loading nanoscale material in vitro and evaluated its safety and effect on mice in vivo. Results showed that insulin-loaded PAM-PAspPBA-b-PEG is glucose-sensitive, safer and more effective than regular insulin injection. This study provides a basis for future development of smart insulin delivery systems.

11.
Mol Ther Nucleic Acids ; 13: 580-589, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30439646

RESUMO

Long noncoding RNAs (lncRNAs) are closely associated with the molecular mechanisms underlying cancer development, and it would be highly useful to study their expression and mechanisms in cervical cancer too. The current study investigated lncRNA799 expression in cervical cancer in order to determine its clinical importance in the progression of cervical cancer. lncRNA799 expression was studied in 218 cervical cancer samples. Expression of lncRNA799 was significantly higher in the cervical cancer tissue than in the adjacent normal tissue. Overexpression of lncRNA799 was found to have a significant correlation with FIGO stage, SCC-Ag level, and lymphatic metastasis, and it was also associated with poor survival. Ectopic expression of lncRNA799 promoted the metastasis of SiHa cells, whereas lncRNA799 knockdown had an inhibitory effect on metastasis. Western blot analysis demonstrated that lncRNA799 promotes the expression of transducing ß-like protein 1-related protein (TBL1XR1), and that lncRNA799 and TBL1XR1 expression show strong correlation in cervical cancer. Moreover, lncRNA799 modulated the expression of TBL1XR1 by acting as a competitive endogenous RNA (ceRNA) for miR-454-3P. The results indicate that lncRNA799 could be used as a novel marker of cervical cancer prognosis. Thus, targeting the ceRNA network involving lncRNA799 could be a potential treatment strategy against cervical cancer.

12.
Molecules ; 23(8)2018 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-30060618

RESUMO

Obesity and nonalcoholic fatty liver disease (NAFLD) are highly prevalent and cause numerous metabolic diseases. However, drugs for the prevention and treatment of obesity and NAFLD remain unavailable. In this study, we investigated the effects of mogrosides (luo han guo, LH) in Siraitia grosvenorii saponins on high-fat-diet-induced obesity and NAFLD in mice. We found that compared with the negative control, LH reduced body and liver weight. LH also decreased fat accumulation and increased AMP-activated protein kinase (AMPK) phosphorylation (pAMPK) levels in mouse livers. We also found that high-purity mogroside V upregulated pAMPK expression in HepG2 cells. In addition, high-purity mogroside V inhibited reactive oxygen species production and upregulated sequestosome-1 (SQSTM1, p62) expression in THP-1 cells. These results suggest that LH may affect obesity and NAFLD by enhancing fat metabolism and antioxidative defenses. Mogroside V may be a main component of LH. However, the exact molecular mechanisms and active components responsible for the inhibitory effects of LH on obesity and NAFLD require further investigation.


Assuntos
Fármacos Antiobesidade/farmacologia , Anticolesterolemiantes/farmacologia , Momordica/química , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Triterpenos/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Anticolesterolemiantes/química , Anticolesterolemiantes/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Tamanho do Órgão/efeitos dos fármacos , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Saponinas/química , Saponinas/isolamento & purificação , Saponinas/farmacologia , Proteína Sequestossoma-1/agonistas , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Células THP-1 , Triterpenos/química , Triterpenos/isolamento & purificação
13.
Cell Oncol (Dordr) ; 41(3): 269-282, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29368272

RESUMO

PURPOSE: Papillary thyroid cancer (PTC) is more common in women than in men. It has been suggested that estrogen may be involved in its development, as has previously been shown for breast, endometrial and ovarian cancer. The purpose of this study was to assess correlations between the expression of the estrogen receptor alpha36 (ERα36) and the glucose regulated proteins GRP78 and GRP94 (chaperones involved in glycoprotein folding) and various PTC clinicopathological features, as well as to evaluate the potential usefulness of these three potential oncogenic proteins in the prediction of aggressive PTC behavior. METHODS: ERα36, GRP78 and GRP94 protein expression in 218 primary PTC tissues and PTC-derived BCPAP cells was examined using immunohistochemistry, Western blotting and immunocytochemistry. The proliferative, invasive and migrative capacities of BCPAP cells in which the respective genes were either exogenously over-expressed or silenced were assessed using BrdU incorporation and Transwell assays, respectively. RESULTS: We found that ERα36, GRP78 and GRP94 protein expression was upregulated in the primary PTC tissues tested. We also found that ERα36, GRP78 and GRP94 expression modulation affected the proliferation, invasion and migration of PTC-derived BCPAP cells. A positive correlation and a positive feedback loop were noted between ERα36, GRP78 and GRP94 protein expression in the primary PTC tissues and in BCPAP cells, respectively. High ERα36 expression in combination with a high GRP78/ GRP94 expression was found to have a stronger correlation with extrathyroid extension (ETE), lymph node metastasis (LNM), distant metastasis (DM) and high TNM stage than high ERα36 expression in combination with either high GRP78 or high GRP94 expression (p = 0.028 for ETE, p = 0.002 for DM and p ≤ 0.001 for LNM and high TNM stage) or high ERα36 expression alone (p < 0.001 for ETE, LNM, DM and high TNM stage). CONCLUSIONS: From our data we conclude that a concomitant high expression of ERα36, GRP78 and GRP94 is strongly associated with aggressive PTC behavior and may be used as a predictor for ETE, LNM, DM and high TNM stage.


Assuntos
Carcinoma Papilar/metabolismo , Receptor alfa de Estrogênio/genética , Proteínas de Choque Térmico/metabolismo , Glicoproteínas de Membrana/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Estudos de Coortes , Estradiol/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/genética , Humanos , Masculino , Glicoproteínas de Membrana/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Análise Serial de Tecidos , Células Tumorais Cultivadas
14.
Sci Rep ; 7(1): 15924, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29162843

RESUMO

While the natural foods of the western honey bee (Apis mellifera) contain diverse phytochemicals, in contemporary agroecosystems honey bees also encounter pesticides as floral tissue contaminants. Whereas some ubiquitous phytochemicals in bee foods up-regulate detoxification and immunity genes, thereby benefiting nestmates, many agrochemical pesticides adversely affect bee health even at sublethal levels. How honey bees assess xenobiotic risk to nestmates as they forage is poorly understood. Accordingly, we tested nine phytochemicals ubiquitous in nectar, pollen, or propolis, as well as five synthetic xenobiotics that frequently contaminate hives-two herbicides (atrazine and glyphosate) and three fungicides (boscalid, chlorothalonil, and prochloraz). In semi-field free-flight experiments, bees were offered a choice between paired sugar water feeders amended with either a xenobiotic or solvent only (control). Among the phytochemicals, foragers consistently preferred quercetin at all five concentrations tested, as evidenced by both visitation frequency and consumption rates. This preference may reflect the long evolutionary association between honey bees and floral tissues. Of pesticides eliciting a response, bees displayed a preference at specific concentrations for glyphosate and chlorothalonil. This paradoxical preference may account for the frequency with which these pesticides occur as hive contaminants and suggests that they present a greater risk factor for honey bee health than previously suspected.

15.
Mol Clin Oncol ; 7(3): 378-382, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28781814

RESUMO

Programmed death ligand-1 (PD-L1) is a potentially important tumor immunotherapy target. However, whether PD-L1 expression is associated with survival in nasopharyngeal carcinoma (NPC) remains controversial. The aim of the present study was to investigate the association between PD-L1 expression and prognosis in NPC. The expression of PD-L1 was assessed in tumor specimens from 120 patients with NPC using immunohistochemistry. Staining was evaluated using the H-score method. The associations between PD-L1 expression and clinical characteristics and prognosis were analyzed. Overall, 78% of the patients had stage I-III and 22% had stage IV disease. The estimated 5-year overall survival (OS) and disease-free survival (DFS) rates for the entire cohort were 87.5 and 70.1%, respectively. PD-L1 expression was detected in 85 (71%) patients and was localized to the tumor cells. High tumor expression of PD-L1 (median H-score ≥5) was associated with significantly poorer OS (P=0.023) and DFS (P=0.002). Univariate analysis indicated that low PD-L1 expression was associated with better DFS compared with high PD-L1 expression (HR=0.163, 95% CI: 0.044-0.600, P=0.006 for DFS). Multivariate analysis revealed that T stage (HR=8.190, 95% CI: 1.355-18.152; P=0.023) and PD-L1 expression level (HR=0.124, 95% CI: 0.031-0.509; P=0.001) served as independent prognostic factors for DFS. In conclusion, tumor PD-L1 expression was found to be a significant prognostic factor in NPC, and high PD-L1 expression may be of prognostic value for recurrence and metastasis following conventional treatments.

16.
PLoS One ; 12(7): e0181767, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28732039

RESUMO

Triploid plants are usually highly aborted owing to unbalanced meiotic chromosome segregation, but limited viable gametes can participate in the transition to different ploidy levels. In this study, numerous meiotic abnormalities were found with high frequency in an intersectional allotriploid poplar (Populus alba × P. berolinensis 'Yinzhong'), including univalents, precocious chromosome migration, lagging chromosomes, chromosome bridges, micronuclei, and precocious cytokinesis, indicating high genetic imbalance in this allotriploid. Some micronuclei trigger mini-spindle formation in metaphase II and participate in cytokinesis to form polyads with microcytes. Unbalanced chromosome segregation and chromosome elimination resulted in the formation of microspores with aneuploid chromosome sets. Fusion of sister nuclei occurs in microsporocytes with precocious cytokinesis, which could form second meiotic division restitution (SDR)-type gametes. However, SDR-type gametes likely contain incomplete chromosome sets due to unbalanced segregation of homologous chromosomes during the first meiotic division in triploids. Misorientation of spindles during the second meiotic division, such as fused and tripolar spindles with low frequency, could result in the formation of first meiotic division restitution (FDR)-type unreduced gametes, which most likely contain three complete chromosome sets. Although 'Yinzhong' yields 88.7% stainable pollen grains with wide diameter variation from 23.9 to 61.3 µm, the pollen viability is poor (2.78% ± 0.38). A cross of 'Yinzhong' pollen with a diploid female clone produced progeny with extensive segregation of ploidy levels, including 29 diploids, 18 triploids, 4 tetraploids, and 48 aneuploids, suggesting the formation of viable aneuploidy and unreduced pollen in 'Yinzhong'. Individuals with different chromosome compositions are potential to analyze chromosomal function and to integrate the chromosomal dosage variation into breeding programs of Populus.


Assuntos
Segregação de Cromossomos/genética , Cromossomos de Plantas/genética , Meiose/genética , Populus/genética , Aneuploidia , Cruzamento/métodos , Diploide , Ploidias , Pólen/genética , Tetraploidia , Triploidia
17.
Sci Rep ; 7: 46245, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28387303

RESUMO

Citrus species are among the most important fruit crops. However, gene regulation and signaling pathways related to etiolation in this crop remain unknown. Using Illumina sequencing technology, modification of global gene expression in two hybrid citrus cultivars-Huangguogan and Shiranuhi, respectively-were investigated. More than 834.16 million clean reads and 125.12 Gb of RNA-seq data were obtained, more than 91.37% reads had a quality score of Q30. 124,952 unigenes were finally generated with a mean length of 1,189 bp. 79.15%, 84.35%, 33.62%, 63.12%, 57.67%, 57.99% and 37.06% of these unigenes had been annotated in NR, NT, KO, SwissProt, PFAM, GO and KOG databases, respectively. Further, we identified 604 differentially expressed genes in multicoloured and etiolated seedlings of Shiranuhi, including 180 up-regulated genes and 424 down-regulated genes. While in Huangguogan, we found 1,035 DEGs, 271 of which were increasing and the others were decreasing. 7 DEGs were commonly up-regulated, and 59 DEGs down-regulated in multicoloured and etiolated seedlings of these two cultivars, suggesting that some genes play fundamental roles in two hybrid citrus seedlings during etiolation. Our study is the first to provide the transcriptome sequence resource for seedlings etiolation of Shiranuhi and Huangguogan.


Assuntos
Citrus/genética , Estiolamento/genética , Plântula/genética , Transcriptoma , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Anotação de Sequência Molecular , Reprodutibilidade dos Testes
18.
BMC Cancer ; 17(1): 131, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28196505

RESUMO

BACKGROUND: Due to the uncommon nature of primary spinal epidural lymphomas (PSELs), there has been little research looking at prognostic indicators for the tumor. To our knowledge, this is the largest study to evaluate possible clinical and pathologic prognostic factors in PSEL patients. METHODS: We retrospectively reviewed 130 cases of PSEL, including 36 Chinese patients and 94 published case reports from 1985 to 2015. Patient treatment regimens included surgery (S; n = 119), surgery followed by chemotherapy (S + CT; n = 25), surgery followed by radiotherapy (S + RT; n = 26), and surgery followed by chemotherapy and radiotherapy (S + CT + RT; n = 50). RESULTS: Review of the most recent case follow-up data (time varied) found 51 patients (47%) alive and tumor-free, 10 patients (9%) alive with tumor present, and 47 patients (44%) deceased. The 3-year overall survival (OS) and disease-free survival (DFS) rates were 81.1% and 46.3%, respectively. Favorable prognostic factors found by univariate analysis were female sex, B-cell lymphoma diagnosis, cervical spine location, and combined modality treatment. Furthermore, multivariate analysis revealed that thoracic spine location (HR = 4.629, 95% CI = [1.911, 31.667], P = 0.042 for OS) and the lack of combined modality treatment (HR = 12.697, 95% CI = [2.664, 48.612], P < 0.0001 for DFS) were associated with poor survival in PSEL patients. CONCLUSIONS: PSEL demonstrates specific clinical features and is associated with a relatively good prognosis. Thoracic spine location is a significant poor prognostic factor, and combined modality treatment is associated with improved disease-free survival, but not overall survival.


Assuntos
Terapia Combinada/métodos , Linfoma/terapia , Adolescente , Adulto , Idoso , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Criança , Pré-Escolar , Espaço Epidural/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
19.
Insects ; 8(1)2017 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-28216580

RESUMO

Because certain flavonols and phenolic acids are found in pollen and nectar of most angiosperms, they are routinely ingested by Apis mellifera, the western honey bee. The flavonol quercetin and the phenolic acid p-coumaric acid are known to upregulate detoxification enzymes in adult bees; their presence or absence in the diet may thus affect the toxicity of ingested pesticides. We conducted a series of longevity assays with one-day-old adult workers to test if dietary phytochemicals enhance longevity and pesticide tolerance. One-day-old bees were maintained on sugar syrup with or without casein (a phytochemical-free protein source) in the presence or absence of quercetin and p-coumaric acid as well as in the presence or absence of two pyrethroid insecticides, bifenthrin and ß-cyfluthrin. Dietary quercetin (hazard ratio, HR = 0.82), p-coumaric acid (HR = 0.91) and casein (HR = 0.74) were associated with extended lifespan and the two pyrethroid insecticides, 4 ppm bifenthrin (HR = 9.17) and 0.5 ppm ß-cyfluthrin (HR = 1.34), reduced lifespan. Dietary quercetin enhanced tolerance of both pyrethroids; p-coumaric acid had a similar effect trend, although of reduced magnitude. Casein in the diet appears to eliminate the life-prolonging effect of p-coumaric acid in the absence of quercetin. Collectively, these assays demonstrate that dietary phytochemicals influence honey bee longevity and pesticide stress; substituting sugar syrups for honey or yeast/soy flour patties may thus have hitherto unrecognized impacts on adult bee health.

20.
Mol Cell Endocrinol ; 442: 68-80, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27940299

RESUMO

The higher incidence of thyroid cancer in women during reproductive years compared with men and the increased risk associated with the therapeutic use of estrogen have strongly suggested that estrogen may be involved in the occurrence and development of thyroid cancer. Cadmium (Cd) is a potent metalloestrogen that disrupts the endocrine system by mimicking the effects of 17ß-estradiol (E2). In the present study, we demonstrate that similar to E2 and G1, a specific agonist for G protein-coupled estrogen receptor (GPER), Cd induces the proliferation, invasion and migration of human WRO and FRO thyroid cancer cells that have endogenous GPER. Moreover, like E2 and G1, Cd leads to a rapid activation of ERK/AKT, and then nuclear translocation of NF-κB, increased expression of cyclin A and D1, and secretion of IL-8, all of which are significantly attenuated by GPER blockage or knock-down in both WRO and FRO cells. Furthermore, the Cd-induced proliferation, invasion and migration are suppressed either by specific inhibitors for GPER, ERK, AKT and NF-κB, or by knock-down of GPER. These results suggest that GPER/ERK&AKT/NF-κB signaling pathway is involved in the Cd-induced proliferation, invasion and migration of GPER-positive thyroid cancer cells.


Assuntos
Cádmio/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Estrogênicos/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Neoplasias da Glândula Tireoide/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclina A/metabolismo , Ciclina D1/metabolismo , Estradiol/metabolismo , Estrogênios/metabolismo , Humanos , Interleucina-8/metabolismo , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Glândula Tireoide/metabolismo
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