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1.
Opt Express ; 26(9): 11909-11914, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29716107

RESUMO

We have used an external cavity self-injection feedback locking (SIFL) system to simultaneously reduce the optical linewidth of over 39 individual wavelength channels of an InAs/InP quantum dot (QD) coherent comb laser (CCL). Linewidth reduction from a few MHz to less than 200 kHz is observed. Measured phase noise spectra clearly indicate a significant decrease in phase noise in the frequency range above 2 kHz. The RF beating signal between two adjacent channels also shows a substantial reduction in 3-dB linewidth from 10 kHz to 300 Hz with the SIFL system, and a corresponding drop in baseline level (-27 dB to -50 dB).

2.
Opt Express ; 26(2): 2160-2167, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29401940

RESUMO

We have developed an InAs/InP quantum dot (QD) C-band coherent comb laser (CCL) module with actively stabilized absolute wavelength and power, and channel spacing of 34.462 GHz with ± 100 ppm accuracy. The total output power is up to 46 mW. The integrated average relative intensity noise (RIN) values of the lasing spectrum and a filtered single channel at 1540.19 nm were -165.6 dB/Hz and -130.3 dB/Hz respectively in the frequency range from 10 MHz to 10 GHz. The optical linewidth of the 45 filtered individual channels between 1531.77 nm to 1543.77 nm ranged from 850 kHz to 2.16 MHz. We have also analyzed the noise behaviors of each individual channel.

3.
Nanotechnology ; 27(13): 135703, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26894375

RESUMO

Porous MnCo2O4 hollow nanocages have been fabricated via a simple template method using carbon spheres as a template. The hydrophilic surface of carbon spheres can adsorb Mn(2+) and Co(2+) ions simultaneously to form Mn,Co-adsorbed carbon spheres. The calcination of Mn,Co-adsorbed carbon spheres can result in porous hollow nanocages of MnCo2O4. The MnCo2O4 hollow nanocages are built by nanoscale MnCo2O4 crystals. Because of the unique porous hollow nanostructures, the resulting MnCo2O4/KB cathode shows an efficient electrocatalytic performance in LiTFSI/TEGDME electrolyte-based Li-O2 batteries. The MnCo2O4 hollow nanocages as the cathode catalysts can deliver better performance during the discharge/charge processes and good cycle stability compared with that of the pure KB carbon. The preliminary results manifest that porous MnCo2O4 hollow nanocages are promising high-performance cathode catalysts for Li-O2 batteries. This template technique is a simple, general, low-cost and controllable method and can be extended to prepare other transition metal oxide hollow nanostructures.

5.
Eur Rev Med Pharmacol Sci ; 24(6): 3360-3384, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32271454

RESUMO

Beginning in December 2019, coronavirus disease 2019 (COVID-19), due to 2019-nCoV infection, emerged in Wuhan and spread rapidly throughout China and even worldwide. Employing combined therapy of modern medicine and traditional Chinese medicine has been proposed, in which Ma Xing Shi Gan Decoction (MXSGD) was recommended as a basic prescription and applied widely in the clinical treatment of COVID-19. We investigated the underlying mechanism of MXSGD in treating COVID-19 utilizing the approaches of integrating network pharmacology. A total of 97 active ingredients of MXSGD were screened out, and 169 targets were predicted. The protein-protein interaction network exhibited hub targets of MXSGD, such as Heat shock protein 90, RAC-alpha serine/threonine-protein kinase, Transcription factor AP-1, Mitogen-activated protein kinase 1, Cellular tumor antigen p53, Vascular endothelial growth factor A, and Tumour necrosis factor. Gene Ontology functional enrichment analysis demonstrated that the biological processes altered within the body after taking MXSGD were closely related to the regulation of such processes as the acute inflammatory response, chemokine production, vascular permeability, response to oxygen radicals, oxidative stress-induced apoptosis, T cell differentiation involved in the immune response, immunoglobulin secretion, and extracellular matrix disassembly. KEGG enrichment analysis indicated that the targets of MXSGD were significantly enriched in inflammation-related pathways, immunomodulation-related pathways, and viral infection-related pathways. The therapeutic mechanisms of MXSGD on COVID-19 may primarily involve the following effects: reducing inflammation, suppressing cytokine storm, protecting the pulmonary alveolar-capillary barrier, alleviating pulmonary edema, regulating the immune response, and decreasing fever.


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Medicina Tradicional Chinesa , Pneumonia Viral/tratamento farmacológico , COVID-19 , Infecções por Coronavirus/genética , Infecções por Coronavirus/metabolismo , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/metabolismo , SARS-CoV-2
6.
Opt Express ; 17(16): 13609-14, 2009 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-19654768

RESUMO

We have developed an InAs/InP quantum dot (QD) gain material using a double cap growth procedure and GaP sublayer to tune QDs into the L-band. By using it, a passive L-band mode-locked laser with pulse duration of 445 fs at the repetition rate of 46 GHz was demonstrated. The 3-dB linewidth of the RF spectrum is less than 100 KHz. The lasing threshold injection current is 24 mA with an external differential quantum efficiency of 22% and an average output power of 27 mW. The relationship between pulse duration and 3-dB spectral bandwidth as a function of injection current was investigated.


Assuntos
Arsenicais/química , Índio/química , Lasers , Fosfinas/química , Pontos Quânticos , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Micro-Ondas , Modelos Teóricos , Espalhamento de Radiação , Semicondutores
9.
Opt Express ; 16(14): 10835-40, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18607499

RESUMO

For the first time, we report femtosecond pulses from a passive single-section InAs/InP quantum-dot (QD) mode-locked laser (MLL) with the active length of 456 microm and ridge width of 2.5 microm at the C-band wavelength range. Without any external pulse compression, the transform-limited Gaussian-pulses are generated at the 92 GHz repetition rate with the 312 fs pulse duration, which is the shortest pulse from any directly electric-pumping semiconductor MLLs to our best knowledge. The lasing threshold injection current and external differential quantum efficiency are 17.2 mA and 38%, respectively. We have also investigated the working principles of the proposed QD MLLs.

10.
Bone Marrow Transplant ; 51(11): 1470-1475, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27322852

RESUMO

A comparison was conducted of 213 patients with haematologic malignancies who underwent HLA-identical sibling (n=108) or HLA-haploidentical (n=105) haematopoietic cell transplantation (haplo-HCT) at our centre. The conditioning regimen included fludarabine, busulphan, cyclophosphamide and antilymphocyte globulin (ATG) (FBCA). The total dose of ATG differed between identical and haploidentical groups (3.75 mg/kg versus 12.5 mg/kg). The cumulative incidences of grade II-IV acute GvHD in the identical and haploidentical groups were 20.4% and 21.9% (P=0.73), and 2-year cumulative incidences of chronic GvHD were 36.4% and 24.1% (P=0.17), respectively. The 3-year probabilities of non-relapse mortality for identical and haploidentical groups were 20.5% and 34.9% (P=0.048), and for relapse were 22.2% and 21.0% (P=0.85), respectively. The 3-year overall survivals in the identical and haploidentical groups were 62.6% and 52.6% (P=0.054), whereas the 3-year disease-free survivals were 54.7% and 43.1% (P=0.14), respectively. In the multivariate analysis, patients in the high-risk group exhibited reduced survival, and the higher dose of mononuclear or CD34+ cells resulted in an increase in the likelihood of survival. In conclusion, haplo-HCT based on an FBCA conditioning regimen could achieve nearly comparable outcomes to HLA-identical sibling HCT.


Assuntos
Neoplasias Hematológicas/terapia , Transplante Haploidêntico/métodos , Adolescente , Adulto , Antígenos CD34/análise , Criança , Pré-Escolar , Feminino , Doença Enxerto-Hospedeiro , Neoplasias Hematológicas/mortalidade , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Irmãos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Haploidêntico/mortalidade , Resultado do Tratamento , Adulto Jovem
11.
Bone Marrow Transplant ; 50(8): 1092-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25961770

RESUMO

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is an alternative for patients who need a transplant without having conventional donors. One hundred and five consecutive patients with hematologic malignancies who underwent G-CSF-primed peripheral blood haplo-HSCT without in vitro T-cell depletion in our single center were reported in this study. Patients were categorized into the intermediate-risk group (n=28) or high-risk group (n=77) according to the risk stratification. The conditioning regimen included fludarabine, busulfan, cyclophosphamide and anti-lymphocyte globulin. The cumulative incidence of grades II-IV acute GvHD (aGvHD) on day +100 was 21.9%, and that of grades III-IV aGvHD was 14.3%. The 2-year cumulative incidence of total chronic GvHD (cGvHD) was 24.1%, and that of extensive cGvHD was 5.6% in 83 eligible patients. The 3-year cumulative incidence rates of relapse and no relapse mortality were 21.9% and 30.5%, respectively. After a median follow-up of 35 months, the 3-year probabilities of overall and disease-free survival for the intermediate-risk and high-risk groups were 63.2% and 39.8% and 61.2% and 32.2%, respectively. In multivariate analysis, the outcome of survival (overall survival and disease-free survival) was associated with the risk stratification, disease status at transplant and dose of infused mononuclear cells. Our results suggest that unmanipulated peripheral blood stem cell allograft performed with fludarabine, busulfan, cyclophosphamide and anti-lymphocyte globulin conditioning regimen is feasible.


Assuntos
Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Depleção Linfocítica/métodos , Linfócitos T , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Aloenxertos , Bussulfano/administração & dosagem , Criança , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Feminino , Seguimentos , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
12.
Clin Hemorheol Microcirc ; 18(1): 75-84, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9653589

RESUMO

Using the method of inducing spherocytic anemia in the rabbit with antibody serum, we have developed an animal model in which red blood cells (RBCs) can nearly grow synchronously. With this model, we determined that the surface charge density on the RBC membrane decreased with cell aging. The change was not linear, being much more profound in the latter half of RBC life span. There was a positive correlation between the mean RBC density and its "age" (r = 0.847, p < 0.01). However, the density distribution of the RBCs at the same "age" showed a broad range, and the density values for RBC groups with different ages showed considerable overlap. This indicates that the density gradient technique can be used to separate RBC population into fractions with different mean ages, but has a low resolving power for obtaining individual RBCs of a given "age".


Assuntos
Envelhecimento Eritrocítico/fisiologia , Anemia/sangue , Animais , Galinhas , Modelos Animais de Doenças , Eletroforese , Membrana Eritrocítica/fisiologia , Eritrócitos/imunologia , Coelhos
13.
Artigo em Zh | MEDLINE | ID: mdl-1307279

RESUMO

A comparative study was conducted on the efficacy of mosquito larvicides EBTI and SBTI. The results showed that: 1. The residual efficacy of EBTI was remarkably higher than that of SBTI at 0.007-0.002ppm BTI concentration (P < 0.01), the mosquito larvae mortality of EBTI remained 100% until the 4th week; in contrast, the mosquito larva mortality of SBTI gradually and obviously declined from the 2nd to 4th week after treatment (x2 = 8.17-24.08), and reached 0 at the 4th week. 2. The lowest BTI concentration of EBTI at which a high efficacy persisted for 4 weeks was 0.007ppm BTI, the mosquito larva mortality remaining 100%.


Assuntos
Anopheles , Bacillus thuringiensis , Controle Biológico de Vetores , Animais , Bacillus thuringiensis/classificação , Cápsulas , Larva
14.
Cell Death Dis ; 5: e1221, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24810057

RESUMO

The tumor suppressor gene p53 regulates apoptosis in response to DNA damage. Promoter selectivity of p53 depends on mainly its phosphorylation. Particularly, the phosphorylation at serine-46 of p53 is indispensable in promoting pro-apoptotic genes that are, however, poorly determined. In the current study, we identified palmdelphin as a pro-apoptotic gene induced by p53 in a phosphorylated serine-46-specific manner. Upregulation of palmdelphin was observed in wild-type p53-transfected cells, but not in serine-46-mutated cells. Expression of palmdelphin was induced by p53 in response to DNA damage. In turn, palmdelphin induced apoptosis. Intriguingly, downregulation of palmdelphin resulted in necroptosis-like cell death via ATP depletion. Upon DNA damage, palmdelphin dominantly accumulated in the nucleus to induce apoptosis. These findings define palmdelphin as a target of serine-46-phosphorylated p53 that controls cell death in response to DNA damage.


Assuntos
Apoptose , Núcleo Celular/metabolismo , Dano ao DNA , Proteínas de Membrana/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/genética , Mutação , Necrose , Fosforilação , Interferência de RNA , Serina , Fatores de Tempo , Transfecção , Proteína Supressora de Tumor p53/genética
15.
ACS Appl Mater Interfaces ; 4(3): 1608-13, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22360340

RESUMO

Highly porous wirelike TiO(2) nanostructures have been synthesized by a simple two-step process. The morphological and structural characterizations reveal that the TiO(2) wires typically have diameters from 0.4 to 2 µm, and lengths from 2 to 20 µm. The TiO(2) wires are highly porous and comprise of interconnected nanocrystals with diameters of 8 ± 2 nm resulting in a high specific surface area of 252 m(2) g(-1). The effects of experimental parameters on the structure and morphology of the porous wirelike TiO(2) have been investigated and the possible formation processes of these porous nanostructures are discussed. Galvanostatic charge/discharge tests indicate that the porous wirelike TiO(2) samples exhibit stable reversible lithium ion storage capacities of 167.1 ± 0.7, 152.1 ± 0.8, 139.7 ± 0.3, and 116.1 ± 1.1 mA h g(-1) at 0.5, 1, 2, and 5 C rates, respectively. Such improved performance could be ascribed to their unique porous and 1D nanostructures facilitating better electrolyte penetration, higher diffusion rate of electrons and lithium ion, and variation of accommodated volumes during the charge/discharge cycles.

16.
Zhonghua Liu Xing Bing Xue Za Zhi ; 18(3): 150-2, 1997 Jun.
Artigo em Zh | MEDLINE | ID: mdl-9812462

RESUMO

This paper reported an epidemiological investigation on human and animal infection to Eperythrozoon in 5 provinces. The results showed that Eperythrozoon infection existed in human as well an in animals in those provinces. Due to geographical variation, the infection rates were different. The infection rate was not associated with sex and age in human. The overall infection rate of different Eperythrozoonoses was higher than in healthy humans. The cases of Eperythrozoonoses among human and pig-herd were reported in this paper.


Assuntos
Reservatórios de Doenças , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária , Doenças dos Suínos/epidemiologia , Adolescente , Adulto , Animais , Bovinos , Criança , Pré-Escolar , China/epidemiologia , Cricetinae , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/epidemiologia , Prevalência , Coelhos , Suínos
17.
Artigo em Zh | MEDLINE | ID: mdl-11986694

RESUMO

OBJECTIVE: To observe and evaluate the influence of a new antiviral treatment scheme on HBV replication and mutation during treating chronic hepatitis B. METHODS: In the test group, lamivudine, IFN alpha-2b, Astragalus membranaceus were chosen as a triplex superimposed treatment scheme for treating the patients who were on the state of HBV high replication and involved in the clinical condition of chronic hepatitis B. The control group was treated with lamivudine alone. The observed parameters percentage of patients in whom HBV DNA became undetectable (serum HBV DNA<1.6 ng/L), HBeAg/anti-HBe seroconversion rate; HBV DNA serum level; HBV YMDD mutation rate and pre-C region mutation rate. RESULTS: Compared with that of the control group, HBV DNA undetectable rate of the test group increased markedly at weeks 12, 36, 48(P <0.05), HBeAg negative rate of the group increased markedly at week 36, 48(P <0.05), while anti-HBe positive rate increased only at week 48 (31.58 vs.19.23%, P <0.05). After 4 weeks of treatment, HBV DNA serum level of both the test group and the control group reduced very remarkably (P <0.01), and at week 48, reduced more significantly (P <0.001). Compared with the control group, HBV DNA serum level of the test group reduced notably at week 12 (P <0.05) and very notable at week 36 and 48(P <0.01). At week 12, the pre-C region mutation occurred in the test group, and at week 24, 36,48, the pre-C region and YMDD mutations occurred in both the test group and the control group. CONCLUSIONS: As to anti-viral treatment of chronic hepatitis B, the triplex superimposed treatment had better efficacy than lamivudine alone.


Assuntos
Antivirais/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Lamivudina/uso terapêutico , Fitoterapia , Adolescente , Adulto , Idoso , Astrágalo , Astragalus propinquus , Quimioterapia Combinada , Feminino , Vírus da Hepatite B/genética , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Recombinantes , Replicação Viral/efeitos dos fármacos
18.
Shi Yan Sheng Wu Xue Bao ; 34(1): 35-43, 2001 Mar.
Artigo em Zh | MEDLINE | ID: mdl-12549008

RESUMO

Reactive oxygen species (ROS), such as H2O2, can be produced by enzymes involved in electron leakage of respiration chain in mitochondria, and by neurochemical enzymes such as monoamine oxidase in neural cells. ROS are toxic to cells, and can result in cell death. ROS also play an important role in some diseases, especially in neurodegenerative diseases by yet unknown mechanisms. In the current research, the N-2a neuroblastoma cell was treated with H2O2, and the morphological changes of cell death were characterized. Our results show that N-2a cell death is different from classical apoptosis, but belongs type II nerve cell programmed death, which shows condensed chromatin within intact nuclear envelope and no apoptotic body. The chromatin DNA of dead cells shows no internucleosomal cleavage, as well as no requirement for caspase-3, 1 activity. However, the H2O2-induced N-2a cell death can be inhibited by Bcl-XL. It can be concluded that type II nerve cell death is the result of cell toxicity mediated by ROS. The results pave the way for further research of type II nerve cell death.


Assuntos
Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Neuroblastoma/patologia , Espécies Reativas de Oxigênio/farmacologia , Animais , Camundongos , Células Tumorais Cultivadas
19.
Opt Lett ; 29(19): 2222-4, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15524361

RESUMO

We evaluate a wavelength interrogation technique based on an arrayed waveguide grating (AWG). Initial results show that the Bragg wavelength of fiber Bragg grating (FBG) sensors can be precisely interrogated by thermally scanning an AWG-based demultiplexer. The technique potentially offers a low-cost, compact, and high-performance solution for the interrogation of FBG distributed sensors and multisensor arrays.

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