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We propose a scheme to achieve nonreciprocal parity-time (P T)-symmetric magnon laser in a P T-symmetric cavity optomagnonical system. The system consists of active and passive optical spinning resonators. We demonstrate that the Fizeau light-dragging effect induced by the spinning of a resonator results in significant variations in magnon gain and stimulated emitted magnon numbers for different driving directions. We find that utilizing the Fizeau light-dragging effect allows the system to operate at ultra-low thresholds even without reaching gain-loss balance. A one-way magnon laser can also be realized across a range of parameters. High tunability of the magnon laser is achieved by changing the spinning speed of the resonators and driving direction. Our work provides a new way to explore various nonreciprocal effects in non-Hermitian magnonic systems, which may be applied to manipulate photons and magnons in multi-body non-Hermitian coupled systems.
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We propose a scheme to achieve a tunable nonreciprocal magnon laser with parametric amplification in a hybrid cavity optomagnonical system, which consists a yttrium iron garnet (YIG) sphere and a spinning resonator. We demonstrate the control of magnon laser can be enhanced via parametric amplification, which make easier and more convenient to control the magnon laser. Moreover, we analyze and evaluate the effects of pump light input direction and amplification amplitude on the magnon gain and laser threshold power. The results indicate that we can obtian a higher magnon gain and a broader range of threshold power of the magnon laser. In our scheme both the nonreciprocity and magnon gain of the magnon laser can be increased significantly. Our proposal provides a way to obtain a novel nonreciprocal magnon laser and offers new possibilities for both nonreciprocal optics and spin-electronics applications.
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We report a novel mutation on the ß-globin gene, Hb Hezhou [ß64(E8)GlyâSer; HBB: c.193G>A] that was detected in two unrelated Chinese individuals. Patient 1 also carried an α+-thalassemia (α+-thal) -α4.2 (leftward) deletion, but hematological analyses showed no clinical consequences. Patient 2 was heterozygous for Hb Hezhou. Hemoglobin (Hb) analysis was performed using capillary electrophoresis (CE) and high performance liquid chromatography (HPLC). The Hb variant remained undetected using HPLC, while an additional peak was detected by CE. The finding of Hb Hezhou indicates that the possibilities of rare Hb variants should be alerted in the thalassemia screening program and precisely diagnosed depending on the Hb separation technique used.
Assuntos
Hemoglobinas Anormais , Talassemia alfa , Hemoglobinas Anormais/genética , Heterozigoto , Humanos , Mutação , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Globinas beta/genéticaRESUMO
This study aimed to assess whether chrysin(ChR) can inhibit epithelial-mesenchymal transition(EMT) of type â ¡ alveolar epithelial cell and produce anti-pulmonary fibrosis effect by regulating the NF-κB/Twist 1 signaling pathway. Sixty rats were randomly divided into the control group, the bleomycin(BLC) group, BLC+ChR(50 mg·kg~(-1)) group and BLC+ChR(100 mg·kg~(-1)) group, with 15 rats in each group. The pulmonary fibrosis model was induced by intratracheal injection of BLC(7 500 U·kg~(-1)). Rats were orally administered with different doses of ChR after BLC injection for 28 days. The cells were divided into control group, TGF-ß1 group(5 ng·mL~(-1)), and TGF-ß1+ChR(1, 10, 100 µmol·L~(-1)) groups. The type â ¡ alveolar epithelial cells were treated with TGF-ß1 for 24 h, and then treated with TGF-ß1 for 48 h in the presence or absence of different doses of ChR(1, 10 and 100 µmol·L~(-1)). The morphological changes and collagen deposition in lung tissues were analyzed by HE staining, Masson staining and immunohistochemistry. The mRNA and protein expression levels of collagen â , E-cadherin, zonula occludens-1(ZO-1), vimentin, alpha smooth muscle actin(α-SMA), inhibitor of nuclear factor kappa B alpha(IκBα), nuclear factor-kappa B p65(NF-κB p65), phospho-NF-κB p65(p-p65) and Twist 1 in lung tissues and cells were detected by qPCR and Western blot, respectively. The animal experiment results showed that as compared with the BLC group, after administration of ChR for 28 days, bleomycin-induced pulmonary fibrosis in rats was significantly relieved, collagen â expression in lung tissues was significantly reduced(P<0.05 or P<0.01), and EMT of alveolar epithelial cells was obviously inhibited [the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], concomitantly with significantly reduced IκBα and p65 phosphorylation level in cytoplasm and decreased NF-κB p65 and Twist 1 expression in nucleus(P<0.05 or P<0.01). The cell experiment results showed that different doses of ChR(1, 10 and 100 µmol·L~(-1)) significantly reduced TGF-ß1-induced collagen â expression(P<0.05 or P<0.01), significantly inhibited EMT of type â ¡ alveolar epithelial cells[the expression levels of E-cadherin and ZO-1 were increased and the expression levels of vimentin and α-SMA were decreased(P<0.05 or P<0.01)], and inhibited IκBα and p65 phosphorylation in cytoplasm and down-regulated NF-κB p65 and Twist 1 expression in nucleus induced by TGF-ß1(P<0.05 or P<0.01). The results suggest that ChR can reverse EMT of type â ¡ alveolar epithelial cell and alleviate pulmonary fibrosis in rats, and its mechanism may be associated with reducing IκBα phosphorylation and inhibiting NF-κB p65 phosphorylation and nuclear transfer, thus down-regulating Twist 1 expression.
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Transição Epitelial-Mesenquimal , NF-kappa B , Células Epiteliais Alveolares/metabolismo , Animais , Flavonoides , NF-kappa B/genética , NF-kappa B/metabolismo , Ratos , Transdução de Sinais , Fator de Crescimento Transformador beta1/genéticaRESUMO
OBJECTIVES: To evaluate the safety and efficacy of microwave ablation (MWA) with the assistance of continuous cool saline injection (CCSI) in patients with primary hyperparathyroidism (PHPT). METHODS: Between November 1, 2014, and February 29, 2016, 22 patients with PHPT were enrolled and treated with ultrasound-guided MWA assisted by CCSI. The levels of parathyroid hormone (PTH) and serum calcium were recorded before and after the MWA. Patients were divided into two groups (normalized and unnormalized groups) according to treatment efficacy. Fisher's exact test and the Mann-Whitney test were used to compare data between the two groups. Timing differences in serum PTH and calcium levels were analyzed with repeated measures analysis of variance. RESULTS: Normalized outcomes for both PTH and calcium levels were achieved in 19 of 22 (86.36%) patients with PHPT. In the normalized group, PTH levels remained normal for 12 months after MWA. PTH levels in the unnormalized group were outside the reference range at six of seven follow-ups within 12 months following MWA. By contrast, serum calcium levels gradually decreased in all patients in both groups. The mean serum PTH and mean calcium levels at 6 months after therapy were significantly lower than those before MWA (both p < 0.05). A transient voice change developed in eight patients. One patient experienced hypocalcaemia, which was corrected by oral calcium supplementation within 2 months. CONCLUSIONS: US-guided MWA assisted by CCSI is safe and effective for destroying parathyroid gland tissue and may serve as a therapeutic alternative for patients with PHPT. KEY POINTS: ⢠Microwave ablation is a new option for patients with hypercalcemic or normocalcemic primary hyperparathyroidism. ⢠Microwave ablation can decrease PTH and calcium levels with sustained efficacy in most patients. ⢠Treatment is safe and causes only transient side effects.
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Diatermia/métodos , Hiperparatireoidismo Primário/terapia , Micro-Ondas/uso terapêutico , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hiperparatireoidismo Primário/diagnóstico , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
This work was designed to obtain the valuable compounds with antioxidant, anti-proliferative and anti-inflammatory activities from Astragalus chinensis. Ethyl acetate fraction obtained from A. chinensis L.f. had significant antioxidant, anti-proliferative and anti-inflammatory activities. Subsequently, five single compounds were separated and purified, which were identified as formononetin (1), rhamnocitrin (2), calycosin (3), ß-daucosterol (4), rhamnocitrin-3-O-ß-d-glucoside (5). The results displayed that formononetin and rhamnocitrin exhibited significant cytotoxicity actions against tumor cell lines. Calycosin exerted the strongest anti-inflammatory effect of inhibition effects on NO production in macrophages.
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This study aims to prepare nimodipine/tetramethylpyrazine-loaded poly(D, L-lactide-co-glycolide) dual-drug nanoparticles (NMD/TMP-NPs) and investigate pharmacokinetics and brain distribution to evaluate the possibility of enhancing the drug effect of dual-drug nanoparticles. NMD/TMP-NPs were prepared via W/O/W emulsion solvent evaporation. Entrapment efficiency and drug loading of NMD/TMP-NPs were investigated by ultracentrifugation, and drug release behavior in vitro was studied by dialysis method. The pharmacokinetic and brain distribution were studied in SD mice administered intravenously with NMD/TMP-NPs in comparison with NMD-suspension, NMD/TMP-suspension and NMD-NPs, (NMD-NPs+TMP)-suspension. According to the results, the entrapment efficiency and drug loading of NMD were (79.71±0.73)%, (1.74±0.02)%, those of TMP were (40.26±1.51)% and (4.38±0.16)%. The nanoparticles showed the property of sustained release. On the basis of the major parameters for in vivo pharmacokinetic and brain distribution, t1/2ß of NMD-suspension, NMD/TMP-suspension and NMD-NPs, (NMD-NPs+TMP)-suspension, NMD/TMP-NPs were (1.097±0.146), (1.055±0.06), (1.950±0.140), (1.860±0.096), (2.497±0.475ï¼ h, CL were (0.778±0.098), (1.133±0.111), (0.247±0.023), (0.497±0.040), (0.297±0.024) hâ¢L-1, AUC0-t in rat plasma were (514.218±60.383), (352.916±33.691), (1 618.429±240.198), (804.110±75.804), (1 349.058±215.497) µgâ¢hâ¢L⻹, respectively, and AUC0-t in brain were 0.301 9, 0.624 8, 1.068 6, 1.313 0, 1.046 5 mgâ¢hâ¢L⻹, respectively. According to the in vivo study, the pharmacokinetic behavior of NMD were markedly prolonged by adding TMP or prepared dual-drug nanoparticles.
Assuntos
Química Encefálica , Nanopartículas , Nimodipina/farmacocinética , Pirazinas/farmacocinética , Animais , Encéfalo/metabolismo , Preparações de Ação Retardada , Tamanho da Partícula , Poliglactina 910 , Ratos , Ratos Sprague-Dawley , SuspensõesRESUMO
BACKGROUND: Rapid regeneration of the residual liver is one of the key determinants of successful partial hepatectomy (PHx). At present, there is a lack of recognized safe, effective, and stable drugs to promote liver regeneration. It has been reported that vagus nerve signaling is beneficial to liver regeneration, but the potential mechanism at play here is not fully understood. AIM: To explore the effect and mechanism of hepatic vagus nerve in liver regeneration after PHx. METHODS: A PHx plus hepatic vagotomy (Hv) mouse model was established. The effect of Hv on liver regeneration after PHx was determined by comparing the liver regeneration levels of the PHx-Hv group and the PHx-sham group mice. In order to further investigate the role of interleukin (IL)-22 in liver regeneration inhibition mediated by Hv, the levels of IL-22 in the PHx-Hv group and the PHx-sham group was measured. The degree of liver injury in the PHx-Hv group and the PHx-sham group mice was detected to determine the role of the hepatic vagus nerve in liver injury after PHx. RESULTS: Compared to control-group mice, Hv mice showed severe liver injury and weakened liver regeneration after PHx. Further research found that Hv downregulates the production of IL-22 induced by PHx and blocks activation of the signal transducer and activator of transcription 3 (STAT3) pathway then reduces the expression of various mitogenic and anti-apoptotic proteins after PHx. Exogenous IL-22 reverses the inhibition of liver regeneration induced by Hv and alleviates liver injury, while treatment with IL-22 binding protein (an inhibitor of IL-22 signaling) reduce the concentration of IL-22 induced by PHx, inhibits the activation of the STAT3 signaling pathway in the liver after PHx, thereby hindering liver regeneration and aggravating liver injury in PHx-sham mice. CONCLUSION: Hv attenuates liver regeneration after hepatectomy, and the mechanism may be related to the fact that Hv downregulates the production of IL-22, then blocks activation of the STAT3 pathway.
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OBJECTIVE: To establish the serial cell lines, derived from the same parental gallbladder cancer cell line GBC-SD, with highly metastatic potential via different routes and characterize their biological behaviors to understand the different metastasis mechanisms via lymph and blood. METHODS: The spleen-liver metastasis model and footpad-inguinal lymph node metastasis model were established. GBC-SD was injected into spleen or footpad of nude mice. Then the highly metastasized subpopulations via lymph and blood were isolated. Their differences in morphology, genetic background, proliferation, migration, invasion and adhesion were revealed by comparing the lymphatic-disseminating and hematogenous-disseminating subpopulations with parental cells. RESULTS: The lymphatic-disseminating and hematogenous-disseminating subpopulations were successfully isolated and designated as GBC-SD/HL and GBC-SD/M3 respectively. They demonstrated the identical genetic background with GBC-SD. In comparison with parental cells, the hematogenous-disseminating subpopulation was morphologically characterized with epithelial-mesenchymal transition (EMT) while it was not shown in the lymphatic-disseminating subpopulation. Furthermore, the hematogenous-disseminating subpopulation showed the strongest migrating capacity but the lymphatic-disseminating subpopulation demonstrated a stronger invasive and adhesive ability. CONCLUSION: The whole parental cell GBC-SD, hematogenous-metastasized subpopulation GBC-SD/M3 and lymphatic-disseminating subpopulation GBC-SD/HL is an ideal tool for metastatic mechanism study of gallbladder cancer. EMT plays an important role in hematogenous metastasis while lymphatic metastasis relies more on enhanced invasiveness and adhesion. It may be a target for interfering the lymphatic metastasis of gallbladder cancer.
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Linhagem Celular Tumoral , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/secundário , Animais , Humanos , Neoplasias Hepáticas/patologia , Linfonodos/patologia , Metástase Linfática/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de NeoplasiasRESUMO
Objective: To study the role of Notch-1/Twist-1 axis in the process of epithelial-mesenchymal transition (EMT) of type II alveolar epithelial cells in pulmonary fibrosis (PF) and hope to provide a new theoretical basis for the pathogenesis of PF. Methods: Thirty rats were randomly divided into control group and bleomycin (BLM) group, 15 rats in each group. The PF rat model was induced by intratracheal injection of BLM (7 500 U/kg). Excised inferior lobe of left lung was fixed in 10% formalin for HE staining, Masson staining and transforming growth factor-beta 1 (TGF-ß1) immunohistochemistry staining after BLM injection for 28 days. The cultured type II alveolar epithelial cells (RLE-6TN) were divided into 4 groups (Control group, transforming growth factor-beta 1 (TGF-ß1) group, Notch-1 negative control siRNA (NC siRNA, 100 pmol/L) group and Notch-1 siRNA (100 pmol/L) group), each group was established nine holes. The cells were treated with TGF-ß1 (5.0 ng/ml) for 24 h following NC siRNA or Notch-1 siRNA for 48 h. The mRNA and (or) proteins levels of TGF-ß1, collagen I, collagen III, E-Cadherin, zonula occludens-1 (ZO-1), Vimentin, E-Cadherin, Notch-1, Notch-1 intracellular domain (NICD), Hes-1 and Twist-1 were detected in lung tissue and type II alveolar epithelial cells. Results: In vivo, compared with the control group, the alveolar atrophy, collapse and fusion occurred, alveolar septum widened significantly, and a large number of inflammatory cells infiltrated in the pulmonary interstitial of the rats in the BLM group. And compared with control group, BLM obviously increased collagen deposition and collagen I and collagen III expressions, while the expressions of ZO-1 and E-cadherin were decreased, and the expressions of Vimentin and N-cadherin were increased, and concomitantly with increasing Notch-1, NICD, Hes-1 and Twist-1 expression in lung tissues of rats (Pï¼0.01). In vitro, compared with control group, TGF-ß1 treatment obviously induced collagen I, collagen III, Notch-1, NICD, Hes-1 and Twist-1 expressions, and the expressions of E-cadherin and ZO-1 were decreased and the expressions of Vimentin and N-cadherin were increased(Pï¼0.01). Compared with TGF-ß1 group, Notch-1 siRNA treatment significantly inhibited the expressions of Notch-1, NICD, Hes-1 and Twist-1, and the expressions of E-cadherin and ZO-1 were increased and the expressions of Vimentin and N-cadherin were decreased, and also obviously reduced the expressions of collagen I and collagen III induced by TGF-ß1 (Pï¼0.05 or Pï¼0.01). Conclusion: Notch-1/Twist-1 axis is involved in the EMT process of type II alveolar epithelial cells, suggesting that Notch-1/Twist-1 signaling may be involved in the development of pulmonary fibrosis.
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Células Epiteliais Alveolares/citologia , Transição Epitelial-Mesenquimal , Fibrose Pulmonar , Receptor Notch1/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Bleomicina , Pulmão , Fibrose Pulmonar/induzido quimicamente , Ratos , Transdução de Sinais , Fator de Crescimento Transformador beta1RESUMO
Objective: To observe whether the mechanism of small dose capsaicin (Cap) against pulmonary fibrosis in mouse is mediated by agitating transient receptor potential vanilloid 1 (TRPV1). Methods: A total of 60 BALB/c mice were randomly divided into control (CON) group, bleomycin (BLM)group, Cap (0.5, 1,2 mg/kg) groups and Cap (2 mg/kg) plus SB-452533 (2.5 mg/kg) group. C57BL/6 mice were intratracheally injected with 3.5 mg/kg BLM to induce pulmonary fibrosis model. Animals for drugs treatment received daily drug via subcutaneous injection for 21 days. The morphological changes and collagen deposition in lung tissues were analysed by HE staining, Masson staining and immunohistochemistry. The concentration of calcitonin gene-related peptide (CGRP) in plasma was determined by ELISA. The mRNA and (or) proteins levels of α-CGRP, ß-CGRP, collagen I, collagen III, E-Cadherin, zonula occludens-1 (ZO-1), vimentin, alpha smooth muscle actin (α-SMA), TRPV1, p-ERK1/2 and eukaryotic initiation factor 3a (eIF3a) were detected by qPCR and (or) Western blot. Results: Compared with the BLM group, small dose Cap significantly reduced bleomycin-induced pulmonary fibrosis in mice and obviously reversed alveolar epithelial cells epithelial-mesenchymal transition (EMT) (the expression of E-cadherin and ZO-1 were increased(Pï¼0.05 or Pï¼0.01)and the expression of α-SMA and Vimentin were decreased (Pï¼0.05 or Pï¼0.01) after drugs treatment for 21 day, concomitantly with the increase the expressions of TRPV1 and CGRP (Pï¼0.05 or Pï¼0.01), and inhibiting ERK1/2 phosphorylation and eIF3a expression (Pï¼0.05 or Pï¼0.01). These effects of small dose Cap were abolished in the presence of TRPV1 receptor antagonist SB-452533. Conclusion: The results suggest that small dose Cap can reverse alveolar epithelial cells EMT and alleviate bleomycin-induced pulmonary fibrosis in mice by inhibiting ERK1/2/eIF3asignaling pathway, which is related to agitating TRPV1 receptor and releasing of CGRP.
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Células Epiteliais Alveolares , Capsaicina , Transição Epitelial-Mesenquimal , Fibrose Pulmonar , Células Epiteliais Alveolares/efeitos dos fármacos , Animais , Antipruriginosos/farmacologia , Antipruriginosos/uso terapêutico , Bleomicina/toxicidade , Capsaicina/administração & dosagem , Capsaicina/farmacologia , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Distribuição Aleatória , Fator de Crescimento Transformador beta1RESUMO
The combination of IL-2 (interleukin-2) and GM-CSF (granulocyte/macrophage colony-stimulating factor) has been broadly studied in antitumour immune therapy, but its efficacy is uncertain. To better exert the activities of the two cytokines and study them in a mouse model, we have constructed a bifunctional protein, hIL-2-mGM-CSF (human IL-2-mouse GM-CSF), fused to a C-terminal tag of six histidine residues (His(6)). The fusion protein was expressed in Escherichia coli as IBs (inclusion bodies). After extracting and clarifying the IBs, four methods of protein purification and refolding were compared in order to optimize the preparation technique. Of these methods, the best result was obtained with a four-step process consisting of (1) purification with denaturing affinity chromatography, (2) followed by fully denaturing the protein with system conversion, (3) then refolding by isovolumetric ultrafiltration and (4) finally, purification by anion-exchange chromatography. The purity of the hIL-2-mGM-CSF was approx. 95%, yielding approx. 20 mg of protein/l of culture. The fusion protein retained the natural activities of IL-2 and GM-CSF, with specific activities of 8.7 x 10(6) and 1.1 x 10(7) i.u./mg respectively. Flow-cytometric analysis indicated that hIL-2-mGM-CSF could specifically bind to the corresponding receptor-positive cells. The present study provides important preliminary information for studying the antitumour activity of hIL-2-mGM-CSF in vivo, which will facilitate future clinical research into the use of hIL-2/hGM-CSF in immune therapy.
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Fator Estimulador de Colônias de Granulócitos e Macrófagos/isolamento & purificação , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-2/isolamento & purificação , Interleucina-2/metabolismo , Renaturação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Animais , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Regulação Bacteriana da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/química , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Interleucina-2/genética , Camundongos , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , UltracentrifugaçãoRESUMO
A novel vacuolar Na+/H+ exchanger, CgNHX1, was cloned from a halophytic species Chenopodium glaucum by using reverse transcriptase-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) technique. Sequence alignment and phylogenetic analysis of 22 NHX genes from GenBank as well as the new CgNHX1 gene indicate that NHX genes shared a great degree of similarity, regardless of their glycophytic or halophytic origin. Expression of the CgNHX1 gene was induced by NaCl and peaked at 400 mmol/L NaCl. Overexpression of NHX1 genes in rice enhanced their tolerance to salt stress. However, there is no significant difference in salt tolerance among the transgenic rice plants overexpressing the NHX1 genes from either glycophytic or halophytic species. The Na+ content of both the wild type (WT) and transgenic plants increased when exposed to 50 and 100 mmol/L NaCl, and the Na+ concentration in transgenic plants was marginally higher than that of WT. Our data demonstrate that the overexpression of the NHX1 gene from either glycophytic or halophytic species resulted in the enhanced tolerance to salt stress at a similar level, suggesting that NHX gene per se might not be the reason accounting for the difference in salt tolerance between glycophytes and halophytes.
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Regulação da Expressão Gênica de Plantas , Oryza/genética , Plantas/genética , Plantas/metabolismo , ATPases Vacuolares Próton-Translocadoras/química , ATPases Vacuolares Próton-Translocadoras/fisiologia , Sequência de Aminoácidos , Clonagem Molecular , DNA Complementar/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sais/farmacologia , Homologia de Sequência de Aminoácidos , Cloreto de Sódio/farmacologiaRESUMO
OBJECTIVE: To investigate the effects of epigallocatechin-3-gallate (EGCG) on proliferation and cell cycle of acute promyelocytic leukemia NB4 cell line and to clarify the molecular mechanism. METHODS: NB4 cells were treated with 0,50,75,100 and 125µmol/L of EGCG for 24, 48, 72 and 96 h, respectively. The proliferation level of NB4 cells was measured by CCK-8 assay. The cell cycle progression of NB4 cells was assayed by flow cytometry. The mRNA expression levels of DNMT1, DNMT3a and DAPK1 were detected by RT-PCR. The methylation status of gene was tested by methylation specific PCR, and the expression level of DAPK1 protein was detected by Western blot. RESULTS: The proliferation and cell cycle progression of NB4 cells treated with EGCG were inhibited and showed the characteristic of time-dependent and dose-dependent manner. The expression level of DAPK1 and DNMT3a decreased in NB4 cells treated with EGCG. The expression level of DAPK increased in NB4 cells treated with EGCG, while the methylation of DAPK1 gene decreased. CONCLUSION: EGCG inhibits the proliferation and cell cycle progression of NB4 cells by inhibiting the expression of DNMT1 and DNMT3a and down-regulating the methylation status of DAPK1 gene.
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Leucemia Promielocítica Aguda , Catequina/análogos & derivados , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Quinases Associadas com Morte Celular , Humanos , MetilaçãoRESUMO
The abundance and diversity of ammonia-oxidizing microorganisms in sediments of an aquacultural area of Eastern Lake Taihu were investigated. Real-time quantitative PCR was used to analyze the abundance of archaeal and bacterial amoA genes. Cloned libraries were constructed to investigate the structure and diversity of the microbial community. By comparing community characteristics of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in different zones, we found that:â Copy numbers of the bacterial amoA gene outnumbered those of archaeal amoA genes in the aquacultural zone; â¡Diversity of AOA and AOB was higher in the aquaculture zone and control zone, respectively; ⢠The dominant cluster of AOA and AOB in both sediments of aquiculture zone and control zone was Nitrosopumilus and Nitrosospira respectively. It was therefore the community structure of AOA (rather than AOB) in lake sediments that was affected by aquacultural activity.
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Amônia/química , Aquicultura , Bactérias , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Archaea , Biodiversidade , China , Genes Arqueais , Genes Bacterianos , Lagos/química , Oxirredução , FilogeniaRESUMO
BACKGROUND: Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes (RAG) and RAG-mediated V(D)J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether thebreceptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkathuman T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of Tcell receptor (TCR) gene recombination. METHODS: TCR Dbeta-Jbeta signal joint T cell receptor excision DNA circles (sjTRECs) were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences (RSSs) in the TCRVbeta chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 (CDR3) size of the TCRVbeta chain was examined by the TCR GeneScan technique. RESULTS: RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining (NHEJ) pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dbeta2-Jbeta2 signal joints and ds RSS breaks associated with the Dbeta2 5' and Dbeta 2 3' sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVbeta chain did not change during cell proliferation. CONCLUSIONS: RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire.However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V(D)J recombination and as a "special" model of the coexistence of TCR gene rearrangements and "negative" receptor revision.
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Proteínas de Ligação a DNA/genética , Genes RAG-1 , Genes Codificadores dos Receptores de Linfócitos T , Leucemia de Células T/genética , Proteínas Nucleares/genética , Recombinação Genética , Antígenos Nucleares/genética , Sequência de Bases , Regiões Determinantes de Complementaridade , Quebras de DNA , Humanos , Células Jurkat , Autoantígeno Ku , Dados de Sequência MolecularRESUMO
This study aimed to understand effects of adding corn oil (CO) and soy protein (SP) to corn starch on the physicochemical properties and digestive rates of annealed starch complex and mechanisms of interactions between corn starch (CS), CO and SP. Binary and ternary blends were prepared using CS mixed with CO (10%, dsb) and/or SP (10%, dsb) and incubated in a water bath at 50°C for 14h. Results showed that more agglomerates of the granules were in the ternary blends. With the addition of CO and/or SP, the CS displayed a decreased pasting temperature, an increased peak viscosity and a decreased enthalpy change of amylose-lipid complex dissociation. The CO can reinforce but SP hinder the annealing phenomenon. Results also showed that CO decreased retrogradation of CS, whereas SP increased it. The digestibility studies showed that the addition of CO and SP decreased the content of rapidly digestible starch and increased the sum of slowly digestible starch and resistant starch contents. SP displayed more impact on the digestibility of the ternary blends than CO. The physical barrier of CO, and amylose-lipid complex and protein-starch matrix can provide resistance to starch digestion.
Assuntos
Fenômenos Químicos , Óleo de Milho/química , Digestão , Proteínas de Soja/química , Amido/química , Amido/metabolismoRESUMO
The farming of lake fisheries is an important part of the freshwater fishery industry in China. However, farming patterns of traditional fisheries maintain serious negative effects on the ecosystem of Eastern Lake Taihu. In recent years, the enclosure culture model of this lake has been optimized. In order to investigate the effects of aquaculture on the sediment properties, samples were collected from different areas of the lake (i.e. within the culture areas, outside the culture areas; from the crab-plant co-culture areas, mixed culture areas, ecological restoration areas, and control areas), in different months (January, March, April, August, and November), and at different depths (0-1 cm and 9-10 cm). The results of this sampling indicates that â the concentrations of total nitrogen (TN) and total phosphorus (TP) in the sediments samples collected within the culture areas are slightly higher than samples collected outside the culture areas; â¡ compared to the crab-plant co-culture areas, lower concentrations of TN and TP are found in the samples collected from the mixed culture areas; ⢠in the ecological restoration areas, aquatic plants exhibit certain positive effects with decreasing concentrations of TN and TP in the sediment. The lowest concentrations of TN and TP are detected in the sediment during the growing season of aquatic plants.
Assuntos
Aquicultura , Sedimentos Geológicos/química , Lagos/química , Nitrogênio/análise , Fósforo/análise , Animais , China , Monitoramento Ambiental , Plantas , Estações do Ano , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: The cynomolgus monkey (Macaca fascicularis) is one of the most widely used surrogate animal models for an increasing number of human diseases and vaccines, especially immune-system-related ones. Towards a better understanding of the gene expression background upon its immunogenetics, we constructed a cDNA library from Epstein-Barr virus (EBV)-transformed B lymphocytes of a cynomolgus monkey and sequenced 10,000 randomly picked clones. RESULTS: After processing, 8,312 high-quality expressed sequence tags (ESTs) were generated and assembled into 3,728 unigenes. Annotations of these uniquely expressed transcripts demonstrated that out of the 2,524 open reading frame (ORF) positive unigenes (mitochondrial and ribosomal sequences were not included), 98.8% shared significant similarities (E-value less than 1e-10) with the NCBI nucleotide (nt) database, while only 67.7% (E-value less than 1e-5) did so with the NCBI non-redundant protein (nr) database. Further analysis revealed that 90.0% of the unigenes that shared no similarities to the nr database could be assigned to human chromosomes, in which 75 did not match significantly to any cynomolgus monkey and human ESTs. The mapping regions to known human genes on the human genome were described in detail. The protein family and domain analysis revealed that the first, second and fourth of the most abundantly expressed protein families were all assigned to immunoglobulin and major histocompatibility complex (MHC)-related proteins. The expression profiles of these genes were compared with that of homologous genes in human blood, lymph nodes and a RAMOS cell line, which demonstrated expression changes after transformation with EBV. The degree of sequence similarity of the MHC class I and II genes to the human reference sequences was evaluated. The results indicated that class I molecules showed weak amino acid identities (<90%), while class II showed slightly higher ones. CONCLUSION: These results indicated that the genes expressed in the cynomolgus monkey could be used to identify novel protein-coding genes and revise those incomplete or incorrect annotations in the human genome by comparative methods, since the old world monkeys and humans share high similarities at the molecular level, especially within coding regions. The identification of multiple genes involved in the immune response, their sequence variations to the human homologues, and their responses to EBV infection could provide useful information to improve our understanding of the cynomolgus monkey immune system.
Assuntos
Linfócitos B/metabolismo , Etiquetas de Sequências Expressas , Sistema Imunitário , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Regiões 5' não Traduzidas/genética , Animais , Antígenos de Diferenciação de Linfócitos B/genética , Análise por Conglomerados , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Biblioteca Gênica , Genoma Humano/genética , Humanos , Imunoglobulinas/genética , Íntrons/genética , Ligantes , Complexo Principal de Histocompatibilidade/genética , Família Multigênica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido NucleicoRESUMO
Different methods were used to prepare HLA tetramers and the yields of each method were compared. Our results indicate that preliminary refolding of the heavy chain (Hc) and light chain (beta 2m) yields more monomer than the typical conventional method with urea-solubilized Hc and beta 2m. We then used the corresponding tetramers to detect cytomegalovirus (CMV)-specific cytotoxic T lymphocytes (CTL). Increasing data suggest that the adoptive transfer of CMV-specific CTL constitutes an effective strategy against CMV infections. We designed a method that efficiently induces CMV-specific CTL to a higher frequency in vitro than is currently achieved. This method increased the percentage of CMV-specific CTL from below 1% to 20% of PBL, accounting for more than 40% of CD8+ T cells. Successful HLA tetramer preparation provides the basis for the subsequent detection of CMV-specific CTL in clinical applications.