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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(5): 693-700, 2023 May 06.
Artigo em Zh | MEDLINE | ID: mdl-37165815

RESUMO

Objective: To investigate the toxicity of tris (2-chloropropyl) phosphate (TCIPP) and tributyl phosphate (TnBP) on the growth and development of zebrafish embryos, as well as to explore the underlying mechanisms at the transcriptional level. Methods: With zebrafish as a model, two hpf zebrafish embryos were exposed to TCIPP and TnBP (0.1, 1, 10, 100, 500, and 1 000 µmol/L) using the semi-static method, and their rates of lethality and hatchability were determined. The transcriptome changes of 120 hpf juvenile zebrafish exposed to environmentally relevant concentrations of 0.1 and 1 µmol/L were measured. Results: The 50% lethal concentrations (LC50) of TCIPP and TnBP for zebrafish embryos were 155.30 and 27.62 µmol/L (96 hpf), 156.5 and 26.05 µmol/L (120 hpf), respectively. The 72 hpf hatching rates of TCIPP (100 µmol/L) and TnBP (10 µmol/L) were (23.33±7.72)% and (91.67±2.97)%, which were significantly decreased compared with the control group (P<0.05). Transcriptome analysis showed that TnBP had more differential genes (DEGs) than TCIPP, with a dose-response relationship. These DEGs were enriched in 32 pathways in total, including those involved in oxidative stress, energy metabolism, lipid metabolism, and nuclear receptor-related pathways, using the IPA pathway analysis. Among them, three enriched pathways overlapped between TCIPP and TnBP, including TR/RXR activation and CAR/RXR activation. Additionally, DEGs were also mapped onto pathways of LXR/RXR activation and oxidative stress for TnBP exposure only. Conclusion: Both TCIPP and TnBP have growth and developmental toxicities in zebrafish embryos, with distinct biomolecular mechanisms, and TnBP has a stronger effect than TCIPP.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Embrião não Mamífero/metabolismo , Transcriptoma , Estresse Oxidativo , Poluentes Químicos da Água/metabolismo
2.
J Therm Biol ; 97: 102866, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863430

RESUMO

Organisms with complex ecologies and life-cycle processes may shift physiologically (acclimation in tolerance), developmentally, and/or behaviorally (thermoregulation) in response to changes in climate. As such, climate change may trigger multiple, interacting phenotypic responses, which underscores the nuances of characterizing a species capacity to adapt and respond to climate change. In this study, we use a model frog species, Bufo gargarizans, to examine how three phenotypes, thermal tolerance limits (critical thermal minimum, CTmin and critical thermal maximum, CTmax), ontogeny, and behavioral preferences in temperature (Tpref) respond to different levels of thermal exposure (i.e., acclimation ranging from 10 °C to 30 °C). Acclimation temperature had little effect on Tpref of tadpoles, yet behaviorally they showed strong signs of thermal selection towards an optimum. Both CTmin and CTmax increased with acclimation temperature with an approximate 10% increase in tolerance limits per 1 °C increase in exposure. Development and body size both responded to acclimation temperature, both of which also influenced lower but not upper thermal limits. Our study highlights the idiosyncrasies of estimating climate vulnerability, where multiple phenotypes can respond to shifts in temperature-a complexity that is especially apparent in species with complex life-cycles.


Assuntos
Aclimatação , Anuros/fisiologia , Comportamento Animal , Regulação da Temperatura Corporal , Temperatura , Animais , Mudança Climática , Larva/fisiologia , Fenótipo
3.
Plant Mol Biol ; 103(3): 253-267, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32152894

RESUMO

KEY MESSAGE: A novel QTL (qSCN-PL10) for SCN resistance and related candidate genes were identified in the soybean variety Pingliang xiaoheidou, and plant basal immunity seems to contribute to the SCN resistance. Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is one of the most devastating soybean pests worldwide. The development of host plant resistance represents an effective strategy to control SCN. However, owing to the lack of diversity of resistance genes in soybean varieties, further investigation is necessary to identify new SCN resistance genes. By analyzing the resistance phenotypes of soybean variety Pingliang xiaoheidou (Pingliang, ZDD 11047), we found that it exhibited the different resistance phenotypes from PI 88788 and Peking varieties. Because Pingliang variety contains the Rhg1-a (low copy) haplotype and lacks the resistant Rhg4 haplotype, novel quantitative trait locus might account for their SCN resistance. After sequencing parental lines (Magellan and Pingliang) and 200 F2:3 progenies, a high-density genetic map was constructed using the specific length amplified fragment sequencing method and qSCN-PL10 was identified as a novel locus for SCN resistance. Candidate genes were predicted by RNA sequencing (RNA-seq) in the qSCN-PL10 locus region. The RNA-seq analysis performed also indicated that plant basal immunity plays an important role in the resistance of Pingliang to SCN. These results lay a foundation for the use of marker-assisted breeding to enhance the resistance to SCN.


Assuntos
Glycine max/fisiologia , Glycine max/parasitologia , Nematoides/fisiologia , Doenças das Plantas/parasitologia , Animais , Mapeamento Cromossômico , Cromossomos de Plantas , Regulação da Expressão Gênica de Plantas , Ligação Genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Locos de Características Quantitativas , Glycine max/genética
4.
J Cell Mol Med ; 23(6): 3867-3877, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30968541

RESUMO

Macrophage migration inhibitory factor (MIF) is pleiotropic cytokine that has multiple effects in many inflammatory and immune diseases. This study reveals a potential role of MIF in acute kidney injury (AKI) in patients and in kidney ischemic reperfusion injury (IRI) mouse model in MIF wild-type (WT) and MIF knockout (KO) mice. Clinically, plasma and urinary MIF levels were largely elevated at the onset of AKI, declined to normal levels when AKI was resolved and correlated tightly with serum creatinine independent of disease causes. Experimentally, MIF levels in plasma and urine were rapidly elevated after IRI-AKI and associated with the elevation of serum creatinine and the severity of tubular necrosis, which were suppressed in MIF KO mice. It was possible that MIF may mediate AKI via CD74/TLR4-NF-κB signalling as mice lacking MIF were protected from AKI by largely suppressing CD74/TLR-4-NF-κB associated renal inflammation, including the expression of MCP-1, TNF-α, IL-1ß, IL-6, iNOS, CXCL15(IL-8 in human) and infiltration of macrophages, neutrophil, and T cells. In conclusion, our study suggests that MIF may be pathogenic in AKI and levels of plasma and urinary MIF may correlate with the progression and regression of AKI.


Assuntos
Injúria Renal Aguda/sangue , Oxirredutases Intramoleculares/sangue , Rim/patologia , Fatores Inibidores da Migração de Macrófagos/sangue , Traumatismo por Reperfusão/sangue , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/urina , Adulto , Idoso , Animais , Antígenos de Diferenciação de Linfócitos B/metabolismo , Quimiocina CCL2/metabolismo , Creatinina/sangue , Citocinas/sangue , Modelos Animais de Doenças , Progressão da Doença , Feminino , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/urina , Rim/imunologia , Rim/metabolismo , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/urina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/urina , Receptor 4 Toll-Like/metabolismo
5.
J Sci Food Agric ; 98(1): 328-335, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28585343

RESUMO

BACKGROUND: The objective of the present study was to evaluate the effects of four chemicals on the fermentation quality and aerobic stability of alfalfa (Medicago sativa L.) silage. Wilted alfalfa was ensiled without additive (control), or with formic acid (FA), potassium diformate (KDF), sodium diacetate (SDA) or calcium propionate (CAP). RESULTS: After 60 days of ensiling, the pH values in FA, KDF and SDA silages were lower (P < 0.05) compared to that of control and CAP silages, and chemicals (P < 0.05) decreased butyric acid and ammonia N concentrations and populations of aerobic bacteria and yeasts compared to the control. The SDA and CAP silages had a higher (P < 0.05) lactic acid bacteria content compared to the FA and KDF silages. The SDA and CAP silages had higher (P < 0.05) acetic and propionic acid contents compared to the other silages, respectively. The ammonia N concentrations in the FA and KDF silages were lower compared to the other silages during the first 5 days of aerobic exposure, and then increased sharply to 105 and 100 g kg-1 total N, respectively, which was higher (P < 0.05) than that of the SDA and CAP silages on day 9 of aerobic exposure. Yeasts and aerobic bacteria counts in SDA silage slowly increased and remained at lower levels compared to the other silages after 7 days of aerobic exposure. CONCLUSION: Additives prolonged the aerobic stability duration compared to the control, and the SDA and CAP silages remained stable for more than 216 h, followed by the KDF and FA silages (202 and 196 h, respectively). © 2017 Society of Chemical Industry.


Assuntos
Ácidos Graxos Voláteis/metabolismo , Lactobacillus/metabolismo , Medicago sativa/microbiologia , Sais/metabolismo , Silagem/análise , Aerobiose , Ácidos Graxos Voláteis/química , Fermentação , Medicago sativa/química , Propionatos/metabolismo , Silagem/microbiologia
7.
J Paediatr Child Health ; 53(4): 399-407, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27704652

RESUMO

AIM: The aim of this study is to describe epidemiology, clinical features, laboratory data and severity of respiratory syncytial virus (RSV) acute lower respiratory infection (ALRI) in Malaysian children and to determine risk factors associated with prolonged hospital stay, paediatric intensive care unit (PICU) admission and mortality. METHODS: Retrospective data on demographics, clinical presentation, outcomes and laboratory findings of 450 children admitted into Tuanku Jaafar Hospital in Seremban, Malaysia from 2008 to 2013 with documented diagnosis of RSV ALRI were collected and analysed. RESULTS: Most admissions were children below 2 years old (85.8%; 386/450). Commonest symptoms were fever (84.2%; 379/450), cough (97.8%; 440/450) and rhinorrhea (83.6%; 376/450). The median age among febrile patients (n = 379) was 9.0 months with interquartile range (IQR) of 4.0-19.0 months whereas the median age among those who were apyrexial (n = 71) was 2 months with IQR of 1-6 months (P-value <0.001). 15.3% (69/450) needed intensive care and 1.6% (7/450) died. Young age, history of prematurity, chronic comorbidity and thrombocytosis were significantly associated with prolonged hospital stay, PICU admission and mortality. CONCLUSIONS: Infants less than 6 months old with RSV ALRI tend to be afebrile at presentation. Younger age, history of prematurity, chronic comorbidity and thrombocytosis are predictors of severe RSV ALRI among Malaysian children. Case fatality rate for Malaysian children below 5 years of age with RSV ALRI in our centre is higher than what is seen in developed countries, suggesting that there is room for improvement.


Assuntos
Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/fisiopatologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/fisiopatologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/fisiopatologia , Pré-Escolar , Feminino , Hospitalização , Humanos , Lactente , Malásia/epidemiologia , Masculino , Auditoria Médica , Síndrome do Desconforto Respiratório/diagnóstico , Infecções por Vírus Respiratório Sincicial/diagnóstico , Estudos Retrospectivos , Índice de Gravidade de Doença
8.
Gen Comp Endocrinol ; 228: 48-52, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26873629

RESUMO

Ghrelin has been implicated in the regulation of gastric functional development, and its physiological functions are mediated by Ghrelin-O-acyltransferase (GOAT) which is capable of generating the active form of this polypeptide hormone. However, whether and how ghrelin gene silencing may modify gastric acid secretion and GOAT-Ghrelin system is yet to be explored. The study was performed in gastric mucosal cells from weanling piglets in vitro. We evaluated the effect of ghrelin on gastric acid secretion, gene expression of GOAT and ghrelin as well as ghrelin levels by RNA interference assay. shGhrelin triggered the down-regulation of ghrelin mRNA expression (P<0.05) via an RNAi mechanism, as observed by real-time RT-PCR. In addition, shGhrelin showed reduced total ghrelin production and secretion (P<0.05) using ELISA in vitro. We also detected that GOAT mRNA expression was reduced in shGhrelin group (P<0.05), compared with control groups. In accordance with the GOAT expression, acylated ghrelin production and secretion were reduced in gastric mucosal cells and culture medium (P<0.05). Silencing of ghrelin gene achieved by RNAi-mediation inhibited the activity of H(+)-K(+)-ATPase and pepsin (P<0.05) in gastric mucosal cells. These results indicated that RNAi of Ghrelin gene inhibited the gastric acid secretion with decreased GOAT mRNA and acylated Ghrelin in gastric mucosal cells.


Assuntos
Aciltransferases/metabolismo , Mucosa Gástrica/metabolismo , Regulação da Expressão Gênica , Grelina/antagonistas & inibidores , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , RNA Interferente Pequeno/genética , Aciltransferases/genética , Animais , Células Cultivadas , Grelina/genética , Grelina/metabolismo , ATPase Trocadora de Hidrogênio-Potássio/genética , Técnicas In Vitro , Interferência de RNA , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 44(4): 338-41, 2016 Apr 24.
Artigo em Zh | MEDLINE | ID: mdl-27112613

RESUMO

OBJECTIVE: To evaluate the incidence and risk factors of postoperative delirium in patients post permanent pacemaker implantation. METHODS: Patients underwent permanent pacemaker implantation in our department from September 2013 to February 2015 were included in this study. Delirium was measured by the confusion assessment method on the first three postoperative days. All the patients were divided into the postoperative delirium group and the non-delirium control group according to whether new onset delirium was diagnosed. Risk factors significantly associated with postoperative delirium detected by univariate analysis were entered into multivariable analysis to define the independent predictors of postoperative delirium. RESULTS: A total of 225 patients were enrolled in this study. The incidence of postoperative delirium was 5.3%. Patients developing postoperative delirium were older ((83±5) years vs. (74±11) years, P=0.002), had a significantly higher incidence of blood pressure fluctuations (58.3% (7/12) vs. 4.7% (10/213), P<0.001), hyponatremia (25.0% (3/12) vs. 5.2% (11/213), P=0.030) and had higher systolic blood pressure ((157±35) mmHg vs. (136±22)mmHg, 1 mmHg=0.133 kPa, P=0.007). However, patients developing postoperative delirium had lower preoperative average heart rate ( (47±18)bpm vs. (58±15)bpm, P=0.007). Multiple regression analysis showed that advanced age (OR= 2.984, 95% CI: 1.226-7.624, P=0.016) and blood pressure fluctuations (OR=27.393, 95% CI: 6.735-111.417, P<0.001) are the independent risk factors for pacemaker patients with postoperative delirium. CONCLUSION: Advanced age and blood pressure fluctuations are independent risk factors of postoperative delirium in patients post permanent pacemaker implantation.


Assuntos
Delírio/epidemiologia , Marca-Passo Artificial/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Humanos , Incidência , Análise Multivariada , Fatores de Risco
10.
J Lipid Res ; 56(2): 215-26, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25421060

RESUMO

apoE is a multi-functional protein expressed in several cell types and in several organs. It is highly expressed in adipose tissue, where it is important for modulating adipocyte lipid flux and gene expression in isolated adipocytes. In order to investigate a potential systemic role for apoE that is produced in adipose tissue, mice were generated with selective suppression of adipose tissue apoE expression and normal circulating apoE levels. These mice had less adipose tissue with smaller adipocytes containing fewer lipids, but no change in adipocyte number compared with control mice. Adipocyte TG synthesis in the presence of apoE-containing VLDL was markedly impaired. Adipocyte caveolin and leptin gene expression were reduced, but adiponectin, PGC-1, and CPT-1 gene expression were increased. Mice with selective suppression of adipose tissue apoE had lower fasting lipid, insulin, and glucose levels, and glucose and insulin tolerance tests were consistent with increased insulin sensitivity. Lipid storage in muscle, heart, and liver was significantly reduced. Adipose tissue macrophage inflammatory activation was markedly diminished with suppression of adipose tissue apoE expression. Our results establish a novel effect of adipose tissue apoE expression, distinct from circulating apoE, on systemic substrate metabolism and adipose tissue inflammatory state.


Assuntos
Tecido Adiposo/metabolismo , Apolipoproteínas E/genética , Regulação da Expressão Gênica , Inflamação/metabolismo , Adipócitos/metabolismo , Tecido Adiposo/patologia , Animais , Apolipoproteínas E/metabolismo , Western Blotting , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Obesidade/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Triglicerídeos/metabolismo
11.
Phys Rev Lett ; 114(14): 147004, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910155

RESUMO

We report ^{75}As NMR measurements on the new quasi-one-dimensional superconductor K_{2}Cr_{3}As_{3} (T_{c}∼6.1 K) [J. K. Bao et al., Phys. Rev. X 5, 011013 (2015)]. We found evidence for strong enhancement of Cr spin fluctuations above T_{c} in the [Cr_{3}As_{3}]_{∞} double-walled subnanotubes based on the nuclear spin-lattice relaxation rate 1/T_{1}. The power-law temperature dependence, 1/T_{1}T∼T^{-γ} (γ∼0.25), is consistent with the Tomonaga-Luttinger liquid. Moreover, absence of the Hebel-Slichter coherence peak of 1/T_{1} just below T_{c} suggests an unconventional nature of superconductivity.

12.
Diabetes Obes Metab ; 17(1): 82-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25263215

RESUMO

AIM: To determine if the glucagon-like peptide-1 (GLP-1) receptor agonist albiglutide, once weekly, impairs counter-regulatory responses during hypoglycaemia. METHODS: We conducted a randomized, double-blind, parallel, placebo-controlled study in subjects with type 2 diabetes mellitus. A single dose of albiglutide 50 mg (n = 22) or placebo (n = 22) was administered on day 1. Glucose was clamped on day 4 (to coincide with the approximate albiglutide maximum plasma concentration) at 9.0, 5.0, 4.0, 3.3 and 2.8 mmol/l (162, 90, 72, 59.4 and 50.4 mg/dl), with a post-clamp recovery period to 3.9 mmol/l (70 mg/dl). Hormone measurements were made at each plateau and adverse events (AEs) were recorded. RESULTS: The counter-regulatory hormones glucagon, epinephrine, norepinephrine, growth hormone and cortisol were appropriately suppressed when plasma glucose levels were >4.0 mmol/l (>72 mg/dl), but increased in the albiglutide and placebo groups with glucose levels <3.3 mmol/l (<59.4 mg/dl) in response to hypoglycaemia. The area under the curve geometric mean ratios (albiglutide : placebo), calculated from the clamped plateau of 4.0 mmol/l (72 mg/dl) to the glucose recovery point, were not significantly different for any of the counter-regulatory hormones. When plasma glucose levels were >5.0 mmol/l (>90 mg/dl), albiglutide increased pancreatic ß-cell secretion of C-peptide in a glucose-dependent manner to a greater extent than did placebo, and it was suppressed in each group when levels were <4.0 mmol/l (<72 mg/dl). No significant difference between groups was observed in the recovery time to glucose level ≥3.9 mmol/l (≥70 mg/dl). There were no clinically relevant differences in AEs or other safety variables. CONCLUSIONS: A single 50-mg dose of albiglutide was well tolerated and did not impair the counter-regulatory response to hypoglycaemia. These data provide mechanistic evidence supporting the low intrinsic hypoglycaemic potential of albiglutide.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/agonistas , Glucagon/metabolismo , Hipoglicemia/prevenção & controle , Pâncreas/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Adulto , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Regulação para Baixo/efeitos dos fármacos , Feminino , Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/efeitos adversos , Peptídeo 1 Semelhante ao Glucagon/genética , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Técnica Clamp de Glucose , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Insulina/metabolismo , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Pâncreas/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico
13.
Plant Dis ; 99(4): 442-446, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30699550

RESUMO

Soybean mosaic virus (SMV), belonging to the genus Potyvirus of the family Potyviridae, has a relatively narrow host range almost exclusively confined to leguminous hosts. While disease management through genetic transformation can be an effective approach, soybean remains recalcitrant to routine genetic transformation. In this context, it is important to identify new hosts for SMV that can be used to develop effective transgenic resistance strategies. Transformation in Nicotiana benthamiana is simple and highly efficient; hence, here we demonstrate the infectivity of SMV strain SC7 in N. benthamiana plants. To identify an SMV strain infectious in N. benthamiana, we mechanically inoculated N. benthamiana plants with 37 isolates from 21 (SC1 to SC21) SMV strains. Plants inoculated with isolates of strain SC7 produced mosaic symptoms on leaves. However, N. benthamiana plants inoculated with the 20 other SMV strains showed no visible symptoms. Furthermore, soybean cv. Nannong 1138-2 inoculated with sap prepared from symptomatic N. benthamiana leaves showed typical SMV mosaic symptoms 2 weeks after inoculation. In addition, SMV was detected in symptomatic N. benthamiana and soybean leaves by RT-PCR, DAS-ELISA, and further identified by sequencing. Together, the results indicate that N. benthamiana plants could support multiplication of SMV strain SC7. The findings of this study would be useful for the investigation of SMV resistance using the model plant N. benthamiana.

14.
Clin Exp Immunol ; 175(1): 92-103, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24116893

RESUMO

Retroviral co-infections with human immunodeficiency virus type-1 (HIV-1) and human T cell leukaemia virus type 1 (HTLV-1) or type 2 (HTLV-2) are prevalent in many areas worldwide. It has been observed that HIV-1/HTLV-2 co-infections are associated with slower rates of CD4(+) T cell decline and delayed progression to AIDS. This immunological benefit has been linked to the ability of Tax2, the transcriptional activating protein of HTLV-2, to induce the expression of macrophage inflammatory protein (MIP)-1α/CCL3, MIP-1ß/CCL4 and regulated upon activation normal T cell expressed and secreted (RANTES)/CCL5 and to down-regulate the expression of the CCR5 co-receptor in peripheral blood mononuclear cells (PBMCs). This study aimed to assess the role of Tax2-mediated activation of the nuclear factor kappa B (NF-κB) signalling pathway on the production of the anti-viral CC-chemokines MIP-1α, MIP-1ß and RANTES. Recombinant Tax1 and Tax2 proteins, or proteins expressed via adenoviral vectors used to infect cells, were tested for their ability to activate the NF-κB pathway in cultured PBMCs in the presence or absence of NF-κB pathway inhibitors. Results showed a significant release of MIP-1α, MIP-1ß and RANTES by PBMCs after the activation of p65/RelA and p50. The secretion of these CC-chemokines was significantly reduced (P < 0·05) by canonical NF-κB signalling inhibitors. In conclusion, Tax2 protein may promote innate anti-viral immune responses through the activation of the canonical NF-κB pathway.


Assuntos
Quimiocinas CC/imunologia , Produtos do Gene tax/imunologia , Infecções por HTLV-II/imunologia , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Leucócitos Mononucleares/imunologia , Subunidade p50 de NF-kappa B/imunologia , Transdução de Sinais/imunologia , Fator de Transcrição RelA/imunologia , Linhagem Celular , Feminino , Regulação da Expressão Gênica/imunologia , Infecções por HTLV-II/patologia , Humanos , Imunidade Inata , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/virologia , Masculino
15.
Glob Chang Biol ; 20(6): 1968-78, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24227744

RESUMO

Rice straw burning has accompanied paddy management for millennia, introducing black carbon (BC) into soil as the residue of incomplete combustion. This study examined the contribution of BC to soil organic matter and the rate at which it accumulates in paddy soils as a result of prolonged paddy management. Soil depth profiles were sampled along a chronosequence of 0-2000 years of rice-wheat rotation systems and adjacent non-paddy systems (50-700 years) in the Bay of Hangzhou (Zhejiang province, China). The soil BC content and its degree of condensation were assessed using benzene-polycarboxylic acids (BPCAs) as geochemical markers. The results showed that despite regular long term BC input, BC only contributed 7-11% of total soil organic carbon (SOC) in the topsoil horizons. Nevertheless, along with SOC, paddy soils accumulated BC with increasing duration of management until 297 years to reach a steady-state of 13 t BC ha(-1). This was 1.8 times more than in non-paddy soils. The fate of BC in paddy soils (0-1 m) could be modeled revealing an average annual input of 44 kg ha(-1) yr(-1), and a mean residence time of 303 years. The subsoils contributed at least 50% to overall BC stocks, which likely derived from periods prior to land embankment and episodic burial of ancient topsoil, as also indicated by BPCA pattern changes. We conclude that there is a significant but limited accumulation of C in charred forms upon prolonged paddy management. The final contribution of BC to total SOC in paddy soils was similar to that in other aerobic ecosystems of the world.


Assuntos
Agricultura , Monitoramento Ambiental , Sedimentos Geológicos/análise , Solo/química , Fuligem/análise , Isótopos de Carbono/análise , China , Incêndios , Oryza/química , Estações do Ano
16.
J Lipid Res ; 54(1): 202-13, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23071294

RESUMO

The synthesis of apoE by adipocytes has profound effects on adipose tissue lipid flux and gene expression. Using adipose tissue transplantation from wild-type (WT) to apoE knockout (EKO) mice, we show that adipose tissue also contributes to circulating apoE. Different from circulating apoE produced by bone marrow transplantation (BMT), however, adipose tissue-derived apoE does not correct hyperlipidemia or suppress atherosclerosis. ApoE secreted by macrophages has a more acidic isoform distribution, and it increases binding of reconstituted VLDL particles to hepatocytes and fibroblasts more effectively than apoE secreted by adipocytes. The incremental binding can be entirely accounted for by binding to the LDL receptor. After BMT into EKO hosts, plasma cholesterol and macrophage-derived apoE are largely within IDL/LDL- and HDL-sized particles. After adipose tissue transplantation, most cholesterol and adipocyte apoE remain in VLDL. After BMT, circulating apoE no longer demonstrates predominance of acidic isoforms compared with that circulating after fat transplantation. In conclusion, fat transplantation provides circulating apoE levels similar to those provided by bone marrow transplantation, but it does not suppress hyperlipidemia or atherosclerosis. A potential mechanism contributing to this difference is differential binding to cell surface lipoprotein receptors.


Assuntos
Tecido Adiposo/metabolismo , Apolipoproteínas E/biossíntese , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Hiperlipidemias/metabolismo , Tecido Adiposo/citologia , Animais , Apolipoproteínas E/sangue , Apolipoproteínas E/deficiência , Aterosclerose/sangue , Aterosclerose/patologia , Aterosclerose/cirurgia , Transporte Biológico , Transplante de Medula Óssea , Colesterol/metabolismo , Meios de Cultivo Condicionados/metabolismo , Técnicas de Inativação de Genes , Hiperlipidemias/sangue , Hiperlipidemias/patologia , Hiperlipidemias/cirurgia , Fígado/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Receptores de Superfície Celular/metabolismo
17.
BMC Genomics ; 14: 687, 2013 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-24093224

RESUMO

BACKGROUND: Soybean is an important crop that provides valuable proteins and oils for human use. Because soybean growth and development is extremely sensitive to water deficit, quality and crop yields are severely impacted by drought stress. In the face of limited water resources, drought-responsive genes are therefore of interest. Identification and analysis of dehydration- and rehydration-inducible differentially expressed genes (DEGs) would not only aid elucidation of molecular mechanisms of stress response, but also enable improvement of crop stress tolerance via gene transfer. Using Digital Gene Expression Tag profiling (DGE), a new technique based on Illumina sequencing, we analyzed expression profiles between two soybean genotypes to identify drought-responsive genes. RESULTS: Two soybean genotypes - drought-tolerant Jindou21 and drought-sensitive Zhongdou33 - were subjected to dehydration and rehydration conditions. For analysis of DEGs under dehydration conditions, 20 cDNA libraries were generated from roots and leaves at two different time points under well-watered and dehydration conditions. We also generated eight libraries for analysis under rehydration conditions. Sequencing of the 28 libraries produced 25,000-33,000 unambiguous tags, which were mapped to reference sequences for annotation of expressed genes. Many genes exhibited significant expression differences among the libraries. DEGs in the drought-tolerant genotype were identified by comparison of DEGs among treatments and genotypes. In Jindou21, 518 and 614 genes were differentially expressed under dehydration in leaves and roots, respectively, with 24 identified both in leaves and roots. The main functional categories enriched in these DEGs were metabolic process, response to stresses, plant hormone signal transduction, protein processing, and plant-pathogen interaction pathway; the associated genes primarily encoded transcription factors, protein kinases, and other regulatory proteins. The seven most significantly expressed (|log2 ratio| ≥ 8) genes - Glyma15g03920, Glyma05g02470, Glyma15g15010, Glyma05g09070, Glyma06g35630, Glyma08g12590, and Glyma11g16000 - are more likely to determine drought stress tolerance. The expression patterns of eight randomly-selected genes were confirmed by quantitative RT-PCR; the results of QRT-PCR analysis agreed with transcriptional profile data for 96 out of 128 (75%) data points. CONCLUSIONS: Many soybean genes were differentially expressed between drought-tolerant and drought-sensitive genotypes. Based on GO functional annotation and pathway enrichment analysis, some of these genes encoded transcription factors, protein kinases, and other regulatory proteins. The seven most significant DEGs are candidates for improving soybean drought tolerance. These findings will be helpful for analysis and elucidation of molecular mechanisms of drought tolerance; they also provide a basis for cultivating new varieties of drought-tolerant soybean.


Assuntos
Regulação da Expressão Gênica de Plantas , Genoma de Planta/genética , Glycine max/genética , Glycine max/fisiologia , Transcrição Gênica , Adaptação Fisiológica/genética , Análise por Conglomerados , Desidratação , Secas , Condutividade Elétrica , Perfilação da Expressão Gênica , Biblioteca Gênica , Ontologia Genética , Genes Essenciais , Genótipo , Fenótipo , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Transdução de Sinais/genética , Água
19.
Anim Biotechnol ; 24(2): 81-93, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23534956

RESUMO

Insulin-like growth factor I (IGF1) is a member of the insulin superfamily. It performs important roles in the proliferation and differentiation of skin cell and control of hair cycles and is thought to be a potential candidate gene for goat cashmere traits. In this work, we isolated and characterized three kinds of IGF1 mRNA splicing variants from the liver of Liaoning Cashmere goat, and the expression characterization of the IGF1 mRNA splicing variants were investigated in skin and other tissues of Liaoning cashmere goat. The sequencing results indicated that the classes 1w, 1, and 2 of IGF1 cDNAs in Liaoning cashmere goat, each included an open reading frame encoding the IGF1 precursor protein. The deduced amino acid sequences of the three IGF1 precursor proteins differed only in their NH2-terminal leader peptides. Through removal of the signal peptide and extension peptide, the three IGF1 mRNA splicing variants (classes 1w, 1, and 2) resulted in the same mature IGF1 protein in Liaoning cashmere goat. In skin tissue of Liaoning cashmere goat, class 1 and class 2 were detected in all stages of hair follicle cycling, and they had the highest transcription level at anagen, and then early anagen; whereas at telogen both classes 1 and 2 had the lowest expression in mRNA level, but the class 1 appears to be relatively more abundant than class 2 in skin tissue of Liaoning cashmere goat. However, the class 1w transcript was not detected in the skin tissues. Three classes of IGF1 mRNA were transcribed in a variety of tissues, including heart, brain, spleen, lung, kidney, liver, and skeletal muscle, but class 1 IGF1 mRNA was more abundant than classes 1w and 2 in the investigated tissues.


Assuntos
Cabras/genética , Cabelo/fisiologia , Fator de Crescimento Insulin-Like I/genética , Característica Quantitativa Herdável , Splicing de RNA , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Dados de Sequência Molecular , RNA Mensageiro/química , RNA Mensageiro/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA , Transcrição Gênica
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(3): 438-442, 2022 Mar 20.
Artigo em Zh | MEDLINE | ID: mdl-35426810

RESUMO

OBJECTIVE: To investigate the inhibitory effect of agkistrodon halys venom antitumor component-I (AHVAC-I) on vasculogenic mimicry (VM) formation in triple-negative breast cancer MDA-MB-231 cells and explore its possible mechanism. METHODS: CCK8 assay was used to determine the optimal concentration of AHVAC-I for cell treatment based on its halfinhibitory concentration (IC50). MDA-MB-231 cells were treated with different concentrations of AHVAC-I or 5-Fu, and the changes in vasomimetic capacity of the cells were examined using Matrigel assay. The expression levels of matrix metalloproteinase-2 (MMP2) and MMP9 in the treated cells were detected using quantitative PCR and Western blotting. RESULTS: Compared with the control treatment with culture medium, treatment with 5, 10 and 20 µg/mL AHVAC-I significantly reduced vasomimetic ability of MDA-MB-231 cells in a dose-dependent manner (P < 0.01). MMP2 supplementation obviously restored the vasomimetic ability of the cells inhibited by AHVAC-I. CONCLUSION: AHVAC-I inhibits VM formation in triplenegative breast cancer cells in vitro by down-regulating MMP2 production.


Assuntos
Agkistrodon , Antineoplásicos/farmacologia , Neoplasias de Mama Triplo Negativas , Agkistrodon/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Peçonhas
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