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2.
J Colloid Interface Sci ; 627: 804-814, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35901560

RESUMO

The rational design of ultrathin and few-layered structures for three-dimensional MoS2 nanospheres is crucial for achieving attractive lithium-ion batteries (LIBs). Herein, hollow nanospheres constructed by ultrafine and few-layered MoS2 homogeneously incorporated in N-doped amorphous carbon (HUF-MoS2/NC) have been successfully synthesized as high-performance anode for LIBs. Using Mo-glycerol spheres as templates and dopamine hydrochloride as coordination ligands, hollow Mo-glycerol-polydopamine precursors are formed with Mo-containing groups which are surrounded by organic carbon species. Consequently, the MoS2 is confined to the nanoscale and grows partially amorphous fragments while being uniformly embedded in NC. This unique architecture can not only hinder the substantial restacking between MoS2 interlayers, offering more active sites, but also vastly enhance the electrical conductivity and relieve the mechanical stress ascribed to volume changes. As a result, the HUF-MoS2/NC composite anode exhibits excellent cyclic stability (980mAhg-1 after 300 cycles at 0.2Ag-1) and superior rate performance (498mAhg-1 at 5.0Ag-1) for LIBs.

3.
Oncogene ; 41(18): 2624-2637, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35351996

RESUMO

Tumor therapeutics often target the primary tumor bulk but fail to eradicate therapy-resistant cancer stem cells (CSCs) in quiescent state. These can then become activated to initiate recurrence and/or metastasis beyond therapy. Here, we identified and isolated chemoradiotherapy-resistant CSCs in quiescent state with high capacity of tumor-initiation and tumorsphere formation from three types of breast tumors in mice. Experiments of knockdown and rescue revealed DEK, a nuclear protein, as essential for CSC activation. Exogenous DEK was then used to trigger quiescence exit of CSCs. ChIP-seq and ATAC-seq showed that DEK directly binds to chromatin, facilitating its genome-wide accessibility. The resulting epigenetic events upregulate the expression of cellular activation-related genes including MYC targets, whereas cellular quiescence-related genes including the p53 signaling pathway are silenced. However, twinned with DEK-induced activation, formerly resistant CSCs were then destroyed by chemotherapy in vitro. In mice, traditional chemoradiotherapy concurrent with the injection of DEK-containing exosomes resulted in eradication of primary tumors together with formerly resistant CSCs without recurrence or metastasis. Our findings advance knowledge of the mechanism of quiescent CSC activation and may provide novel clinical opportunities for removal of quiescence-linked therapy resistance.


Assuntos
Neoplasias da Mama , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Divisão Celular , Quimiorradioterapia , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Feminino , Humanos , Camundongos , Células-Tronco Neoplásicas/patologia , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Transdução de Sinais
4.
World J Stem Cells ; 12(11): 1307-1326, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33312400

RESUMO

Quiescent state has been observed in stem cells (SCs), including in adult SCs and in cancer SCs (CSCs). Quiescent status of SCs contributes to SC self-renewal and conduces to averting SC death from harsh external stimuli. In this review, we provide an overview of intrinsic mechanisms and extrinsic factors that regulate adult SC quiescence. The intrinsic mechanisms discussed here include the cell cycle, mitogenic signaling, Notch signaling, epigenetic modification, and metabolism and transcriptional regulation, while the extrinsic factors summarized here include microenvironment cells, extracellular factors, and immune response and inflammation in microenvironment. Quiescent state of CSCs has been known to contribute immensely to therapeutic resistance in multiple cancers. The characteristics and the regulation mechanisms of quiescent CSCs are discussed in detail. Importantly, we also outline the recent advances and controversies in therapeutic strategies targeting CSC quiescence.

5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(5): 708-713, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-32975089

RESUMO

OBJECTIVE: To explore the risk factors of acute kidney injury (AKI) in patients with sepsis in intensive care unit (ICU). METHODS: The medical records of patients diagnosed with sepsis in ICU of West China Hospital of Sichuan University from March 2009 to June 2016 were retrospectively analyzed. Differences between AKI group and Non-AKI group in general data, background disease, ICU entry and exit dates, complications, laboratory data and other related data were analyzed through univariate and multivariate statistical methods. RESULTS: A total of 2331 patients with sepsis were included in the study, including 626 patients in the AKI group and 1695 patients in the Non-AKI group. The multivariate logistic regression analysis revealed that age >40 yr. (odds ratio (OR) =2.752), diabetes (OR=2.563), hypertension/coronary heart disease (OR=1.851), chronic kidney disease (OR=15.876), heart failure (OR=2.295), acute respiratory distress syndrome (OR=2.067), severe acute pancreatitis (OR=2.725), hypotension (OR=2.140), hypoproteinemia (OR=1.596), lactic acidosis (OR=2.164), organ failure>1 (OR=4.480), WBC>10×10 9L -1 (OR=4.166), serum creatinine (OR=4.401), PCT (OR=1.816), Cys-C (OR=7.046), mild anemia (OR=2.107), moderate anemia (OR=3.817), and severe anemia (OR=6.091) were all independent risk factors of SA-AKI. CONCLUSION: Several risk factors are related to the occurrence of SA-AKI in the ICU. Early identification and monitoring of risk factors for SA-AKI and early prevention of AKI can improve the prognosis of sepsis patients.


Assuntos
Injúria Renal Aguda , Pancreatite , Sepse , Doença Aguda , Injúria Renal Aguda/complicações , China/epidemiologia , Humanos , Unidades de Terapia Intensiva , Pancreatite/complicações , Estudos Retrospectivos , Fatores de Risco , Sepse/epidemiologia
6.
Nano Lett ; 20(9): 6738-6743, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32787177

RESUMO

Coupled quantum dots (QDs), usually referred to as artificial molecules, are important not only in exploring fundamental physics of coupled quantum objects but also in realizing advanced QD devices. However, previous studies have been limited to artificial molecules with nonrelativistic Fermions. Here, we show that relativistic artificial molecules can be realized when two circular graphene QDs are coupled to each other. Using scanning tunneling microscopy (STM) and spectroscopy (STS), we observe the formation of bonding and antibonding states of the relativistic artificial molecule and directly visualize these states of the two coupled graphene QDs. The formation of the relativistic molecular states strongly alters distributions of massless Dirac Fermions confined in the graphene QDs. Moreover, our experiment demonstrates that the degeneracy of different angular-momentum states in the relativistic artificial molecule can be further lifted by external magnetic fields. Then, both the bonding and antibonding states are split into two peaks.

7.
BMC Cancer ; 19(1): 988, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31647032

RESUMO

BACKGROUND: Laparoscopic surgery, fast-track perioperative treatment and XELOX chemotherapy are effective strategies for shortening the duration of hospital stay for cancer patients. This trial aimed to clarify the safety and efficacy of the fast-track multidisciplinary treatment (FTMDT) model compared to conventional surgery combined with chemotherapy in Chinese colorectal cancer patients. METHODS: This trial was a prospective randomized controlled study with a 2 × 2 balanced factorial design and was conducted at six hospitals. Patients in group 1 (FTMDT) received fast-track perioperative treatment and XELOX adjuvant chemotherapy. Patients in group 2 (conventional treatment) received conventional perioperative treatment and mFOLFOX6 adjuvant chemotherapy. Subgroups 1a and 2a had laparoscopic surgery and subgroups 1b and 2b had open surgery. The primary endpoint was total length of hospital stay during treatment. RESULTS: A total of 374 patients were randomly assigned to the four subgroups, and 342 patients were finally analyzed, including 87 patients in subgroup 1a, 85 in subgroup 1b, 86 in subgroup 2a, and 84 in subgroup 2b. The total hospital stay of group 1 was shorter than that of group 2 [13 days, (IQR, 11-17 days) vs. 23.5 days (IQR, 15-42 days), P = 0.0001]. Compared to group 2, group 1 had lower surgical costs, fewer in-hospital complications and faster recovery (all P < 0.05). Subgroup 1a showed faster surgical recovery than that of subgroup 1b (all P < 0.05). There was no difference in 5-year overall survival between groups 1 and 2 [87.1% (95% CI, 80.7-91.5%) vs. 87.1% (95% CI, 80.8-91.4%), P = 0.7420]. CONCLUSIONS: The FTMDT model, which integrates laparoscopic surgery, fast-track treatment, and XELOX chemotherapy, was the superior model for enhancing the recovery of Chinese patients with colorectal cancer. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01080547 , registered on March 4, 2010.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Laparoscopia , Idoso , Capecitabina , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Custos e Análise de Custo , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Humanos , Tempo de Internação , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Oxaloacetatos , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento
8.
Cancer Res ; 79(18): 4729-4743, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308046

RESUMO

Quiescent cancer stem cells (CSC) play important roles in tumorigenesis, relapse, and resistance to chemoradiotherapy. However, the determinants of CSC quiescence and how they sustain themselves to generate tumors and relapse beyond resistance to chemoradiotherapy remains unclear. Here, we found that SET domain-containing protein 4 (SETD4) epigenetically controls breast CSC (BCSC) quiescence by facilitating heterochromatin formation via H4K20me3 catalysis. H4K20me3 localized to the promoter regions and regulated the expression of a set of genes in quiescent BCSCs (qBCSC). SETD4-defined qBCSCs were resistant to chemoradiotherapy and promoted tumor relapse in a mouse model. Upon activation, a SETD4-defined qBCSC sustained itself in a quiescent state by asymmetric division and concurrently produced an active daughter cell that proliferated to produce a cancer cell population. Single-cell sequence analysis indicated that SETD4+ qBCSCs clustered together as a distinct cell type within the heterogeneous BCSC population. SETD4-defined quiescent CSCs were present in multiple cancer types including gastric, cervical, ovarian, liver, and lung cancers and were resistant to chemotherapy. SETD4-defined qBCSCs had a high tumorigenesis potential and correlated with malignancy and chemotherapy resistance in clinical breast cancer patients. Taken together, the results from our previous study and current study on six cancer types reveal an evolutionarily conserved mechanism of cellular quiescence epigenetically controlled by SETD4. Our findings provide insights into the mechanism of tumorigenesis and relapse promoted by SETD4-defined quiescent CSCs and have broad implications for clinical therapies. SIGNIFICANCE: These findings advance our knowledge on the epigenetic determinants of quiescence in cancer stem cell populations and pave the way for future pharmacologic developments aimed at targeting drug-resistant quiescent stem cells.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Epigenômica , Metiltransferases/metabolismo , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Fase de Repouso do Ciclo Celular , Animais , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patologia , Carcinoma Basocelular/terapia , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Quimiorradioterapia , Feminino , Humanos , Metiltransferases/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/terapia , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Domínios Proteicos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Cancer ; 145(6): 1517-1528, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30720863

RESUMO

To gain more information on the prevalence of germline mutations in BRCA1/2 and PALB2 genes in the Chinese population, and to explore the effects of the mutation status of these genes on clinical outcomes in patients with breast cancer, we performed a screening for BRCA1/2 and PALB2 mutations in a consecutive series of unselected breast cancer patients in the Chinese population. A total of 2,769 cases were enrolled between June 1993 and September 2017. All of the exons and exon-intron boundaries of the BRCA1/2 and PALB2 genes were screened with next-generation sequencing. Of the 2,769 breast cancer patients, BRCA1, BRCA2 and PALB2 mutations accounted for 2.7% (n = 74), 2.7% (n = 76), and 0.9% (n = 24), respectively. The BRCA1 gene had the highest mutation frequency in patients with triple-negative breast cancer (TNBC), which was 9.6% (n = 42), while the BRCA2 gene had the highest mutation frequency in patients with Luminal, which was 3.2% (n = 58). The disease-free survival (DFS) of BRCA1 mutation carriers was significantly lower than that of noncarriers (adjusted HR = 2.20, 95% CI = 1.15-4.18, p = 0.017). The mutation status of the PALB2 gene was significantly associated with the decline in overall survival (OS) (adjusted HR = 8.38, 95% CI = 2.19-32.11, p = 0.002). No significant difference was found between BRCA2 pathogenic mutation carriers and noncarriers. These results demonstrate that BRCA1 mutation status may be associated with a worse disease progression in patients with breast cancer, and women who harbored a PALB2 mutation might be at a higher risk of death due to breast cancer compared to noncarriers.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Adulto , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Éxons , Feminino , Triagem de Portadores Genéticos , Humanos , Íntrons , Pessoa de Meia-Idade , Prevalência
11.
Chemistry ; 24(68): 18106-18114, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30230075

RESUMO

Designing core-shell electrode materials with desired components and architectures is a promising strategy for boosting electrochemical performance. Here, three-dimensional hierarchical ZnCo2 O4 @Ni(OH)2 core-shell nanosheet arrays have been successfully fabricated on a Ni foam substrate, in which the porous ZnCo2 O4 nanosheet "core" as the conductive scaffold was synthesized by a metal-organic framework (MOF)-templated method, and the ultrathin Ni(OH)2 nanoflakes "shell" with rich active sites were grafted on the ZnCo2 O4 nanosheet through a hydrothermal treatment. When directly used as a free-standing electrode for supercapacitor, these hierarchical ZnCo2 O4 @Ni(OH)2 core-shell nanosheet arrays exhibited a high capacitance of 3063.2 mF cm-2 (1021.1 F g-1 ) at the current density of 1 mA cm-2 . This electrode significantly outperformed individual Ni(OH)2 or ZnCo2 O4 nanosheet arrays, benefiting from the robust core-shell arrays on Ni foam with good electrical conductivity and abundant active sites, as well as the synergetic effect between MOF-derived porous ZnCo2 O4 "core" and the ultrathin Ni(OH)2 "shell". Moreover, the assembled ZnCo2 O4 @Ni(OH)2 //activated-carbon asymmetric supercapacitor displayed excellent energy and power densities (maximum of 40.0 Wh kg-1 and 8.02 kW kg-1 ) and superior cycling stability of 98.4 % retention with 91.2 % coulombic efficiency over 5 000 cycles at 10 A g-1 .

12.
Inorg Chem ; 57(11): 6202-6205, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29756772

RESUMO

A novel hierarchical nanoarray material based on a two-dimensional metal-organic framework (Ni-CAT) and a layered double hydroxide (NiCo-LDH) was fabricated on a nickel foam substrate. By taking advantage of the regular nanostructure and making full use of the high porosity and excellent conductivity, the hybrid material exhibits a high areal capacitance for a supercapacitor (3200 mF cm-2 at 1 mA cm-2).

13.
Dalton Trans ; 47(16): 5639-5645, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29619467

RESUMO

Metal-organic frameworks (MOFs) show great advantages as new kinds of active materials for energy storage. In this study, bimetallic metal-organic frameworks (Ni/Co-MOFs) with nanosheet-assembled flower-like structures were synthesized by etching Ni-MOF microspheres in a cobalt nitrate solution. It can be clearly observed that the amount of Co(NO3)2 and etching time play crucial roles in the formation of Ni/Co-MOF nanosheets. The Ni/Co-MOFs were used as electrode materials for supercapacitors and the optimized Ni/Co-MOF-5 exhibited the highest capacitances of 1220.2 F g-1 and 986.7 F g-1 at current densities of 1 A g-1 and 10 A g-1, respectively. Ni/Co-MOF-5 was further sulfurized, and the derived Ni-Co-S electrode showed a higher specific capacitance of 1377.5 F g-1 at a current density of 1 A g-1 and a retention of 89.4% when the current density was increased to 10 A g-1, indicating superior rate capability. Furthermore, Ni/Co-MOF-5 and Ni-Co-S showed excellent cycling stability, i.e. about 87.8% and 93.7% of initial capacitance can be still maintained after 3000 cycles of charge-discharge. More interestingly, the Ni/Co-MOF-5//AC ASC shows an energy density of 30.9 W h kg-1 at a power density of 1132.8 W kg-1, and the Ni-Co-S//AC ASC displays a high energy density of 36.9 W h kg-1 at a power density of 1066.42 W kg-1. These results demonstrate that the as-synthesized bimetallic Ni/Co-MOF nanosheets and their derived nickel-cobalt sulfides have promising applications in electrochemical supercapacitors.

14.
Dalton Trans ; 46(48): 16821-16827, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29034389

RESUMO

Electrode materials for supercapacitors with one-dimensional porous nanostructures, such as nanowires and nanotubes, are very attractive for high-efficiency storage of electrochemical energy. Herein, ultralong Cu-based porous coordination polymer nanowires (copper-l-aspartic acid) were used as the electrode material for supercapacitors, for the first time. The as-prepared material exhibits a high specific capacitance of 367 F g-1 at 0.6 A g-1 and excellent cycling stability (94% retention over 1000 cycles). Moreover, porous CuO nanotubes were successfully fabricated by the thermal decomposition of this nanowire precursor. The CuO nanotube exhibits good electrochemical performance with high rate capacity (77% retention at 12.5 A g-1) and long-term stability (96% retention over 1000 cycles). The strategy developed here for the synthesis of porous nanowires and nanotubes can be extended to the construction of other electrode materials for more efficient energy storage.

15.
Chin Med J (Engl) ; 130(18): 2163-2169, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28836571

RESUMO

BACKGROUND:: Acute kidney injury (AKI) is the most common and life-threatening systemic complication of rhabdomyolysis. Inflammation plays an important role in the development of rhabdomyolysis-induced AKI. This study aimed to investigate the kidney model of AKI caused by rhabdomyolysis to verify the role of macrophage Toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-κB) signaling pathway. METHODS:: C57BL/6 mice were injected with a 50% glycerin solution at bilateral back limbs to induce rhabdomyolysis, and CLI-095 or pyrrolidine dithiocarbamate (PDTC) was intraperitoneally injected at 0.5 h before molding. Serum creatinine levels, creatine kinase, the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-6, and hematoxylin and eosin stainings of kidney tissues were tested. The infiltration of macrophage, mRNA levels, and protein expression of TLR4 and NF-κB were investigated by immunofluorescence double-staining techniques, reverse transcriptase-quantitative polymerase chain reaction, and Western blotting, respectively. In vitro, macrophage RAW264.7 was stimulated by ferrous myoglobin; the cytokines, TLR4 and NF-κB expressions were also detected. RESULTS:: In an in vivo study, using CLI-095 or PDTC to block TLR4/NF-κB, functional and histologic results showed that the inhibition of TLR4 or NF-κB alleviated glycerol-induced renal damages (P < 0.01). CLI-095 or PDTC administration suppressed proinflammatory cytokine (TNF-α, IL-6, and IL-1ß) production and macrophage infiltration into the kidney (P < 0.01). Moreover, in an in vitro study, CLI-095 or PDTC suppressed myoglobin-induced expression of TLR4, NF-κB, and proinflammatory cytokine levels in macrophage RAW264.7 cells (P < 0.01). CONCLUSION:: The pharmacological inhibition of TLR4/NF-κB exhibited protective effects on rhabdomyolysis-induced AKI by the regulation of proinflammatory cytokine production and macrophage infiltration.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , NF-kappa B/metabolismo , Rabdomiólise/complicações , Receptor 4 Toll-Like/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Western Blotting , Ensaio de Imunoadsorção Enzimática , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/antagonistas & inibidores , Prolina/análogos & derivados , Prolina/farmacologia , Prolina/uso terapêutico , Pirrolidinas/farmacologia , Pirrolidinas/uso terapêutico , Células RAW 264.7 , Rabdomiólise/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Tiocarbamatos/farmacologia , Tiocarbamatos/uso terapêutico , Receptor 4 Toll-Like/antagonistas & inibidores , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
16.
Dalton Trans ; 46(23): 7388-7391, 2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28488714

RESUMO

A hierarchical NiO/NiMn-LDH nanosheet array on Ni foam was prepared via a facile two-step approach and exhibited a high specific capacitance (937 F g-1 at 0.5 A g-1) and good cycling stability (91% retention after 1000 cycles at 5 A g-1). The improved electrochemical performance is benefited from the synergistic properties of hierarchical NiO/LDH nanosheet composites on a conductive substrate.

17.
J Phys Condens Matter ; 29(14): 145301, 2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28102824

RESUMO

Massless charge carriers in gate potentials modulate graphene quantum well transport in the same way that a electromagnetic wave propagates in optical fibers. A recent experiment by Kim et al (2016 Nat. Phys. 12 1022) reports valley symmetry preserved transport in a graphene carrier guider. Based on a tight-binding model, the valley-resolved transport coefficients are calculated with the method of scattering matrix theory. For a straight potential well, valley-resolved conductance is quantized with a value of 2n + 1 and multiplied by 2e 2/h with integer n. In the absence of disorder, intervalley scattering, only occurring at both ends of the potential well, is weak. The propagating modes inside the potential well are analyzed with the help of band structure and wave function distribution. The conductance is better preserved for a longer carrier guider. The quantized conductance is barely affected by the boundaries of different types or slightly changing the orientation of the carrier guider. For a curved model, the state with momentum closes to the neutral point is more fragile to boundary scattering and the quantized conductance is ruined as well.

18.
Chin Med J (Engl) ; 129(9): 1100-7, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27098797

RESUMO

BACKGROUND: Resolvin D1 (RvD1) is a newly found anti-inflammatory bioactive compound derived from polyunsaturated fatty acids. The current study aimed to explore the protective effect of RvD1 on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) and its possible mechanism. METHODS: Both in vivo and in vitro studies were conducted. Male BALB/c mice were randomly divided into control group (saline), LPS group (LPS 5 mg/kg), RvD1 group (RvD1 5 µg/kg + LPS 5 mg/kg), and blockage group (Boc-MLP 5 µg/kg + RvD1 5 µg/kg + LPS 5 mg/kg). Boc-MLP is a RvD1 receptor blocker. The mice were intraperitoneally injected with these drugs and recorded for general condition for 48 h, while the blood and kidneys were harvested at 2, 6, 12, 24, and 48 h time points, respectively (n = 6 in each group at each time point). Human proximal tubule epithelial cells (HK-2) were randomly divided into control group (medium only), LPS group (LPS 5 µg/ml), RvD1 group (RvD1 10 ng/ml + LPS 5 µg/ml), and blockage group (Boc-MLP 10 ng/ml + RvD1 10 ng/ml + LPS 5 µg/ml). The cells were harvested for RNA at 2, 4, 6, 12, and 24 h time points, respectively (n = 6 in each group at each time point). Blood creatinine was tested by using an Abbott i-STAT portable blood gas analyzer. Tumor necrosis factor-α (TNF-α) level was detected by ELISA. Kidney pathology was observed under hematoxylin and eosin (HE) staining and transmission electron microscope (TEM). We hired immune-histological staining, Western blotting, and fluorescence quantitative polymerase chain reaction to detect the expression of RvD1 receptor ALX, nuclear factor-kappa B (NF-κB) signaling pathway as well as caspase-3. Kidney apoptosis was evaluated by TUNEL staining. RESULTS: RvD1 receptor ALX was detected on renal tubular epithelials. Kaplan-Meier analysis indicated that RvD1 improved 48 h animal survival (80%) compared with LPS group (40%) and RvD1 blockage group (60%), while RvD1 also ameliorated kidney pathological injury in HE staining and TEM scan. After LPS stimulation, the mRNA expression of toll-like receptor 4, myeloid differentiation factor 88, and TNF-α in both mice kidneys and HK-2 cells were all up-regulated, while RvD1 substantially inhibited the up-regulation of these genes. Western blotting showed that the phosphorylated-IκB/IκB ratio in LPS group was significantly higher than that in the control group, which was inhibited in the RvD1 group. RvD1 could inhibit the up-regulation of cleaved-caspase-3 protein stimulated by LPS, which was prohibited in RvD1 blockage group. RvD1 group also had a lower proportion of apoptotic nuclei in mice kidney by TUNEL staining compared with LPS group. CONCLUSION: In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.


Assuntos
Injúria Renal Aguda/prevenção & controle , Apoptose/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Lipopolissacarídeos/farmacologia , NF-kappa B/antagonistas & inibidores , Injúria Renal Aguda/induzido quimicamente , Proteínas Adaptadoras de Transdução de Sinal/análise , Animais , Regulação para Baixo , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/análise
19.
Plasmid ; 79: 15-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25681561

RESUMO

In order to clone PCR products and express them effectively in Escherichia coli, a directional cloning system was constructed by generating a T vector based on pQE-30Xa. The vector was prepared by inserting an XcmI cassette containing an endonuclease XcmI site, a kanamycin selective marker, a multiple-cloning-site (MCS) region and an opposite endonuclease XcmI site into the vector pQE-30Xa. The T vector pQE-T with single overhanging dT residues at both 3' ends was obtained by digesting with the restriction enzyme XcmI. For directional cloning, a BamHI site was introduced to the ends of the PCR products. A BamHI site was also located on the multiple cloning site of pQE-T. The PCR products were ligated with pQE-T. The directionally inserted recombinants were distinguished by using BamHI to digest the recombinants because there are two BamHI sites located on the both sides of PCR fragment. In order to identify the T-vector functions, the 14-3-3-ZsGreen and hRBP genes were amplified and a BamHI site was added to the ends of the genes to confirm this vector by ligation with pQE-T. Results showed that the 14-3-3-ZsGreen and hRBP were cloned to the vector pQE-T directly and corresponding proteins were successfully produced. It was here demonstrated that this directional vector is capable of gene cloning and is used to manipulate gene expression very easily. The methodology proposed here involves easy incorporation of the construct into other vectors in various hosts.


Assuntos
Clonagem Molecular , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Escherichia coli/genética , Genes Bacterianos , Vetores Genéticos , Sequência de Bases , DNA Bacteriano/genética , Eletroforese em Gel de Poliacrilamida , Regulação Bacteriana da Expressão Gênica , Marcadores Genéticos , Canamicina/farmacologia , Dados de Sequência Molecular , Plasmídeos/genética , Reação em Cadeia da Polimerase , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
J Diabetes ; 7(6): 858-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25588466

RESUMO

BACKGROUND: The aim of the present study was to investigate the contribution of maturity-onset diabetes of the young (MODY) genes to the etiology of 14 Chinese MODY families and to assess phenotypic differences between patients with MODY but without a known genetic cause of diabetes (MODYX) and those with early onset type 2 diabetes (T2D). METHODS: The study included 14 MODY probands from unrelated families and 59 patients (age of onset ≤35 years) diagnosed as early onset T2D. A standard meal test and metabolic studies were performed to characterize the clinical features of all patients. All probands with MODY were analyzed for nucleotide variations in promoters, exons, and exon-intron boundaries of 13 known MODY genes by direct DNA sequencing. RESULTS: Mutations in 13 known MODY genes were not present in the 14 Chinese families and they were classified as MODYX. However, different polymorphisms were identified, with I27L (42.9%; 12/28) and S487N (46.4%; 13/28) of hepatocyte nuclear factor 4α (HNF1α/MODY3) being two most frequent polymorphisms. Two new polymorphisms, namely T412I and D504H, were detected in carboxyl ester lipase (CEL/MODY8). Compared with patients with early onset T2D, patients with MODYX were diagnosed with diabetes at a younger age (28.3 ± 6.5 vs 24.3 ± 6.5 years; P < 0.05) and had a lower body mass index (BMI; 28.3 ± 6.1 vs 24.1 ± 4.3 kg/m(2) ; P < 0.01) and homeostatic model assessment of ß-cell function (47.6 [22.2-89.4] vs 18.5 [6.5-33.7]; P < 0.05). CONCLUSION: Herein we report on 14 Chinese families with MODYX and describe its phenotype. Compared with early onset T2D, MODYX is characterized by lower BMI and decreased insulin-secreting capacity.


Assuntos
Diabetes Mellitus Tipo 2/genética , Mutação , Polimorfismo Genético , Adolescente , Adulto , Idade de Início , Povo Asiático/genética , Índice de Massa Corporal , China/epidemiologia , Análise Mutacional de DNA , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Insulina/sangue , Células Secretoras de Insulina/metabolismo , Masculino , Fenótipo , Fatores de Risco , Adulto Jovem
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