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1.
Photochem Photobiol Sci ; 18(10): 2442-2448, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384873

RESUMO

In recent years, several drugs have become relatively easy to obtain with the rapid development of the economy and improvement in people's living standards. However, pathogenic bacteria have evolved strains that are resistant to certain drugs, such as antibiotics. Peptides are generally considered to be safe, have high tolerance to drugs, and are easy to manufacture. However, peptides are easily decomposed in complex biological environments. To solve this problem, many studies have modified peptides on the surface of nanomaterials to increase their functionality, biocompatibility, and stability. Meanwhile, nanomaterials have exhibited good absorption of near-infrared (NIR) light. When the NIR laser is focused on nanomaterials, photons are absorbed and the energy of the photons is converted into heat. Low-toxicity NRC03 peptide-conjugated dopamine/nano-reduced-graphene oxide (NRC03-DA/nRGO) nanomaterials are synthesized in this study for antibacterial testing using photothermal technology. The strains used in this study were Gram-positive Staphylococcus aureus (S. aureus). Our results indicated that the synthesized NRC03-DA/nRGO exhibits good absorption of NIR light and high photothermal conversion efficiency. Moreover, the synthesized NRC03-DA/nRGO inhibits the growth and survival of S. aureus. When the NRC03 peptide is modified on the surface of DA/nRGO, its biological stability is improved and the photothermal effect generated by NIR light produces additive effects, thereby indicating potential antibacterial applications.


Assuntos
Antibacterianos/farmacologia , Dopamina/química , Grafite/química , Nanoestruturas/química , Peptídeos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Raios Infravermelhos
2.
Phys Rev Lett ; 121(11): 113204, 2018 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265085

RESUMO

We demonstrate coupling between the atomic spin- and orbital-angular momentum (OAM) of the atom's center-of-mass motion in a Bose-Einstein condensate (BEC). The coupling is induced by Raman-dressing lasers with a Laguerre-Gaussian beam and creates coreless vortices in an F=1 ^{87}Rb spinor BEC. We observe correlations between spin and OAM in the dressed state and characterize the spin texture; the result is in good agreement with the theory. In the presence of the Raman field, our dressed state is stable for 0.1 s or longer, and it decays due to collision-induced relaxation. As we turn off the Raman beams, the vortex cores in the bare spin |m_{F}=1⟩ and |-1⟩ split. These spin-OAM coupled systems with the Raman-dressing approach have great potential for exploring new topological textures and quantum states.

3.
Rhinology ; 56(1): 46-53, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29289975

RESUMO

Various factors have been proposed to be related to refractory chronic rhinosinusitis (CRS). Treatment for refractory CRS is challenging for ear, nose, and throat (ENT) surgeons. The aim of the study was to determine the clinical features associated with the severity of CRS that may necessitate revision surgery by eliminating the bias of the surgeons technique using standardizing surgical procedures. Sinus wall thickness and blood eosinophilia, which may represent the depth of inflammation in CRS, are associated with the need for revision surgery. We found that, when the thickness of the postero-lateral maxillary sinus wall is more than 3.03 mm, there is an increased probability for a need for revision surgery. CRS patients with thickened sinus walls were found to have poorer outcomes. Further research is needed in order to justify this type of surgical procedure for CRS.


Assuntos
Eosinofilia/complicações , Inflamação/patologia , Seio Maxilar/patologia , Seio Maxilar/cirurgia , Rinite/patologia , Rinite/cirurgia , Sinusite/patologia , Sinusite/cirurgia , Doença Crônica , Feminino , Humanos , Inflamação/diagnóstico por imagem , Masculino , Seio Maxilar/diagnóstico por imagem , Pessoa de Meia-Idade , Seleção de Pacientes , Recidiva , Rinite/diagnóstico por imagem , Sinusite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Zhonghua Yi Xue Za Zhi ; 97(28): 2176-2180, 2017 Jul 25.
Artigo em Zh | MEDLINE | ID: mdl-28763895

RESUMO

Objective: To evaluate glycated hemoglobing A1c (HbA1c) in diagnosing metabolic syndrome (MS) in Chinese subjects aged over 50 years. Methods: A community-based cross-sectional survey was conducted between October 2010 and January 2011 in Shipai community, Guangzhou. A total of 1 494 subjects aged over 50 years were investigated. Questionnaire survey and physical examination were performed among all participants. Fasting blood samples were obtained to measure plasma glucose (FPG), blood lipids and HbA1c. MS was defined by the criteria of International Diabetes Federation (IDF), National Cholesterol Education Program-Adult Treatment Panel Ⅲ (ATP Ⅲ)(2005) and Chinese Diabetes Society (CDS), respectively. Receiver operating characteristic (ROC) curves were plotted to explore the accuracy of HbA1c for diagnosing MS. Results: After excluding subjects with missing data, the remaining 1 473 subjects had a median age of 61 years (55-68 years). An HbA1c threshold of 6.1% yielded the highest combination of sensitivity (52.1%) and specificity (84.3%) for diagnosing MS. Using HbA1c≥5.7% as definition of dysglycemia, the prevalence of MS (IDF), MS (ATP Ⅲ) and MS (CDS) were 48.7%, 57.1% and 50.8%, respectively. The κ coefficients were 0.853, 0.768 and 0.730, respectively. Using HbA1c≥6.1% as definition of dysglycemia, the prevalences of MS (IDF), MS (ATP Ⅲ) and MS (CDS) were 41.2%, 45.8% and 39.1%, respectively. The κ coefficients were 0.923, 0.880 and 0.881, respectively. The optimal HbA1c threshold with the highest level of agreement according to IDF, ATP Ⅲ and CDS criteria were 6.1%, 6.3% and 6.3%, respectively. Conclusions: An HbA1c threshold of 6.1% showed a high specificity for diagnosing MS in Chinese subjects aged over 50 years in community-based setting. The optimal HbA1c threshold may vary according to different criteria and populations.


Assuntos
Síndrome Metabólica , Povo Asiático , Glicemia , Estudos Transversais , Hemoglobinas Glicadas , Humanos , Pessoa de Meia-Idade , Prevalência
6.
Occup Med (Lond) ; 66(7): 514-21, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27036149

RESUMO

BACKGROUND: Although post-traumatic stress disorder (PTSD) and depression are commonly observed following injury, few studies have focused on the effect of psychiatric symptoms on return to work (RTW) following occupational injury. AIMS: To determine the impact of psychiatric symptoms on RTW after occupational injury. METHODS: PubMed (1980-2014), MEDLINE (1980-2014) and PsycINFO (1980-2014) databases were examined with linked fields of research in February 2015. Reference lists of eligible articles were also searched. Cohort, case-control, cross-sectional studies and intervention studies were selected according to predefined criteria. Evidence was synthesized qualitatively according to the Downs and Black and Crombie checklist. The standard checklist was used to assess the methodological quality of each study by two reviewers. RESULTS: Five of the 56 records met the inclusion and exclusion criteria. After occupational injury, the rates of RTW after the injuries varied widely, ranging from 31 to 63%. PTSD symptoms and depressive symptoms appeared to be negatively associated with RTW. CONCLUSIONS: Currently, the evidence is insufficient to draw conclusions about the effects of psychiatric symptoms on RTW after occupational injury and more studies are needed. Future studies with large sample sizes are warranted to determine the prevalence of RTW and to detect the psychiatric factors.


Assuntos
Efeitos Psicossociais da Doença , Traumatismos Ocupacionais/complicações , Traumatismos Ocupacionais/psicologia , Retorno ao Trabalho/psicologia , Adulto , Depressão/complicações , Depressão/etiologia , Depressão/psicologia , Humanos , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
7.
Opt Lett ; 36(19): 3741-3, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21964082

RESUMO

We report on a novel method based on intracavity spontaneous mode locking to precisely measure the group refractive indices and temperature dependence of refractive index of Nd:YVO(4) crystal at the wavelength of 1064 nm. All the experimental results are found to agree very well with the most recent measured values. We also confirm that the developed method is applicable to measuring the group refractive indices and the temperature dependence of the refractive indices of other vanadate crystals, as well as nonlinear crystals.

8.
Opt Lett ; 36(23): 4581-3, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22139249

RESUMO

We realize a femtosecond high-power spontaneous mode-locked operation with gigahertz oscillation in a vertical-external cavity surface-emitting laser under the condition of eliminating the internal and external unwanted reflection. We find that the reflectivity of the output coupler has a significant influence not only on the output power but also on the output pulse duration. With an incident pump power of 20 W, we have achieved 2.35 W of average output power with 778 fs pulse duration at a repetition rate of 2.17 GHz. The shortest pulse duration was 654 fs at an average output power of 0.45 W.

9.
J Heart Lung Transplant ; 40(11): 1443-1453, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34253457

RESUMO

BACKGROUND: Mechanical circulatory support (MCS) is increasingly being used as a bridge to transplant in pediatric patients. We compare outcomes in pediatric patients bridged to transplant with MCS from an international cohort. METHODS: This retrospective cohort study of heart-transplant patients reported to the International Society for Heart and Lung Transplantation (ISHLT) registry from 2005-2017 includes 5,095 patients <18 years. Pretransplant MCS exposure and anatomic diagnosis were derived. Outcomes included mortality, renal failure, and stroke. RESULTS: 26% of patients received MCS prior to transplant: 240 (4.7%) on extracorporeal membrane oxygenation (ECMO), 1,030 (20.2%) on ventricular assist device (VAD), and 54 (1%) both. 29% of patients were <1 year, and 43.8% had congenital heart disease (CHD). After adjusting for clinical characteristics, compared to no-MCS and VAD, ECMO had higher mortality during their transplant hospitalization [OR 3.97 & 2.55; 95% CI 2.43-6.49 & 1.42-4.60] while VAD mortality was similar [OR 1.55; CI 0.99-2.45]. Outcomes of ECMO+VAD were similar to ECMO alone, including increased mortality during transplant hospitalization compared to no-MCS [OR 4.74; CI 1.81-12.36]. Patients with CHD on ECMO had increased 1 year, and 10 year mortality [HR 2.36; CI 1.65-3.39], [HR 1.82; CI 1.33-2.49]; there was no difference in survival in dilated cardiomyopathy (DCM) patients based on pretransplant MCS status. CONCLUSION: Survival in CHD and DCM is similar in patients with no MCS or VAD prior to transplant, while pretransplant ECMO use is strongly associated with mortality after transplant particularly in children with CHD. In children with DCM, long term survival was equivalent regardless of MCS status.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Cardiopatias Congênitas/cirurgia , Insuficiência Cardíaca/cirurgia , Transplante de Coração-Pulmão/métodos , Sistema de Registros , Sociedades Médicas , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
12.
Rev Sci Instrum ; 89(10): 10H108, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399905

RESUMO

Recent advances in radio-frequency system-on-chip technology have provided mm-wave fusion plasma diagnostics with the capability to overcome major challenges such as space inefficiency, inflexible installation, sensitivity, susceptibility to EMI, and prohibitively high cost of conventional discrete component assemblies as higher imaging resolution and data accuracy are achieved by increasing the number of channels. Nowadays, shrinking transistor gate lengths on fabrication techniques have enabled hundreds of GHz operation, which is suitable for millimeter-wave diagnostics on current and future tokamaks. The Davis Millimeter Wave Research Center (DMRC) has successfully developed V-band (55-75 GHz) transmitter and receiver chips for Microwave Imaging Reflectometer (MIR) instruments. The transmitter can illuminate 8 different frequencies simultaneously within 55-75 GHz. Moreover, the receiver has the capability to amplify the reflected signal (>30 dB) while offering 10-30× reduction in noise temperature compared to current MIR instruments. Plasma diagnostics requires ultra-wideband (more than 20 GHz) operation which is approximately nine times wider bandwidth than the recent commercial impetus for communication systems. Current efforts are underway for gallium-arsenide monolithic microwave integrated circuit receiver chips at W-band (75-110 GHz) and F-band (90-140 GHz) permitting measurements at higher toroidal magnetic fields.

13.
Sci Rep ; 8(1): 11087, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30038363

RESUMO

Thulium iron garnet (TmIG) films with perpendicular magnetic anisotropy (PMA) were grown on gadolinium gallium garnet (GGG) (111) substrates by off-axis sputtering. High-resolution synchrotron radiation X-ray diffraction studies and spherical aberration-corrected scanning transmission electron microscope (Cs-corrected STEM) images showed the excellent crystallinity of the films and their sharp interface with GGG. Damping constant of TmIG thin film was determined to be 0.0133 by frequency-dependent ferromagnetic resonance (FMR) measurements. The saturation magnetization (Ms) and the coercive field (Hc) were obtained systematically as a function of the longitudinal distance (L) between the sputtering target and the substrate. A 170% enhancement of PMA field (H⊥) was achieved by tuning the film composition to increase the tensile strain. Moreover, current-induced magnetization switching on a Pt/TmIG structure was demonstrated with an ultra-low critical current density (jc) of 2.5 × 106 A/cm2, an order of magnitude smaller than the previously reported value. We were able to tune Ms, Hc and H⊥ to obtain an ultra-low jc of switching the magnetization, showing the great potential of sputtered TmIG films for spintronics.

14.
Nat Biotechnol ; 17(1): 48-52, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9920268

RESUMO

One of the major barriers to the development of antisense therapeutics has been their poor bioavailability. Numerous oligonucleotide modifications have been synthesized and evaluated for enhanced cellular permeation with limited success. Phenoxazine, a tricyclic 2' deoxycytidine analog, was designed to improve stacking interactions between heterocycles of oligonucleotide/RNA hybrids and to enhance cellular uptake. However, the bioactivity and cellular permeation properties of phenoxazine-modified oligonucleotides were unknown. Incorporation of four phenoxazine bases into a previously optimized C-5 propyne pyrimidine modified 7-mer phosphorothioate oligonucleotide targeting SV40 large T antigen enhanced in vitro binding affinity for its RNA target and redirected RNAse H-mediated cleavage as compared with the 7-mer C-5 propynyl phosphorothioate oligonucleotide (S-ON). The phenoxazine/C-5 propynyl U 7-mer S-ON showed dose-dependent, sequence-specific, and target-selective antisense activity following microinjection into cells. Incubation of the phenoxazine/C-5 propynyl U S-ON with a variety of tissue culture cells, in the absence of any cationic lipid, revealed unaided cellular penetration, nuclear accumulation, and subsequent antisense activity. The unique permeation properties and gene-specific antisense activity of the 7-mer phenoxazine/C-5 propynyl U S-ON paves the way for developing potent, cost-effective, self-permeable antisense therapeutics.


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/farmacologia , Oxazinas/química , Animais , Linhagem Celular , Permeabilidade da Membrana Celular/genética , Humanos , Hibridização In Situ , Cinética , Camundongos , Microinjeções , Oligonucleotídeos Antissenso/metabolismo , Oxazinas/farmacologia , RNA/química , RNA/metabolismo , Ratos , Ribonuclease H/metabolismo , Especificidade por Substrato
15.
Cancer Res ; 56(1): 21-6, 1996 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8548765

RESUMO

Presentation of antigenic peptides by MHC class II molecules to CD4+ T cells is critical to the generation of antitumor immunity. In an attempt to enhance MHC class II antigen processing, we linked the sorting signals of the lysosome-associated membrane protein (LAMP-1) to the cytoplasmic/nuclear human papilloma virus (HPV-16) E7 antigen, creating a chimera (Sig/E7/LAMP-1). Previously, we found that expression of this chimera in vitro and in vivo with a recombinant vaccinia vector targeted E7 to endosomal and lysosomal compartments and enhanced MHC class II presentation to CD4+ T cells compared to vaccinia expressing wild-type E7. In the current study, we tested these recombinant vaccinia for in vivo protection against an E7+ tumor, TC-1, which was derived from primary epithelial cells of C57BL/6 mice cotransformed with HPV-16 E6 and E7 and c-Ha-ras oncogenes. All mice vaccinated with 1 x 10(7) plaque-forming units of wild-type E7-vaccinia showed progressive tumor growth when challenged with a tumorigenic dose of TC-1 tumor cells; in contrast, 80% of mice vaccinated with the chimeric Sig/E7/LAMP1 vaccinia remained tumor free 3 months after tumor injection. Furthermore, treatment with the Sig/E7/LAMP-1 vaccinia vaccine cured mice with small established TC-1 tumors, whereas the wild-type E7-vaccinia showed no effect on this established tumor burden. These findings point out the therapeutic limitations of recombinant vaccinia expressing unmodified tumor antigens. Further, they demonstrate that modifications that reroute a cytosolic tumor antigen to the endosomal/lysosomal compartment can profoundly improve the in vivo therapeutic potency of recombinant vaccines.


Assuntos
Antígenos Virais de Tumores/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Neoplasias Experimentais/terapia , Vacinas Sintéticas , Animais , Apresentação de Antígeno , Sequência de Bases , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Neoplasias Experimentais/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/uso terapêutico
16.
Physiotherapy ; 102(4): 309-319, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27553642

RESUMO

BACKGROUND: People with gynaecological cancer commonly suffer from physical and psychological symptoms related to their cancer and cancer treatment. OBJECTIVE: To evaluate and synthesise the evidence examining the effect of interventions with an exercise component for females with gynaecological cancer. DATA SOURCES: Medline, CINAHL, EMBASE, PubMed, PEDro, PsycINFO and Cochrane Library were searched systematically in September 2014. STUDY SELECTION: Randomised controlled trials were included if they investigated the effects of interventions with an exercise component in patients with gynaecological cancer. STUDY APPRAISAL: Two reviewers independently assessed the risk of bias of studies using the PEDro scale. RESULTS: Seven randomised controlled trials on five patient groups involving 221 participants were included. The mean PEDro score was 5.3 (standard deviation 1.5) out of 10. Compared with control groups, the intervention groups showed significantly greater improvements in physical activity levels and body mass index. No significant effects were found for fatigue, depression and health-related quality of life. A meta-analysis of functional exercise capacity and muscle strength was not possible due to insufficient data in the included trials. LIMITATIONS: The majority of studies provided exercise as part of multicomponent intervention programmes. CONCLUSIONS: Interventions with an exercise component appear to be effective at improving physical activity levels and body mass index among patients with gynaecological cancer. Further research is required to examine the effects of exercise interventions alone in this population. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42014014019.


Assuntos
Terapia por Exercício/métodos , Neoplasias dos Genitais Femininos/reabilitação , Força Muscular/fisiologia , Índice de Massa Corporal , Terapia por Exercício/psicologia , Fadiga , Feminino , Neoplasias dos Genitais Femininos/psicologia , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Oncogene ; 35(26): 3376-86, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-26455324

RESUMO

Cholangiocarcinoma (CCA), which is a poor prognosis malignancy that arises from the malignant transformation of cholangiocytes, is associated with chronic inflammation of the biliary epithelium. Thus far, the molecular mechanisms of the origin and neoplastic processes of CCA that are promoted by inflammation are still unclear and need to be fully elucidated. Here using small RNA sequencing to determine the microRNA (miRNA) expression profiles in CCA, we found that let-7c, miR-99a and miR-125b, which are three miRNAs of the same cluster, were downregulated in CCA and targeted interleukin 6 (IL-6), IL-6R and type 1 insulin-like growth factor, which are important cytokines and receptors of the IL-6/signal transducer and activator 3 (STAT3) pathway and have key roles in inflammation and CCA initiation. We also found that enforced expression of let-7c, miR-99a or miR-125b could reduce the activity of STAT3 and further suppress CCA tumorigenicity in vivo and inhibit the migration and invasion of CCA cells in vitro. Surprisingly, let-7c/miR-99a/miR-125b cluster also significantly decreased the ability of CCA cells for cancer stem cell-like mammosphere generation by downregulating CD133 and CD44, which suggests the pivotal roles of let-7c, miR-99a and miR-125b in CCA by regulating both inflammation and stem-like properties. Our findings showed potential links between miRNAs and inflammation, and provide a potential treatment strategy for developing an miRNA-based therapy via IL-6/STAT3 targeting for CCA.


Assuntos
Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Progressão da Doença , Feminino , Estudo de Associação Genômica Ampla , Células HEK293 , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Receptor IGF Tipo 1 , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo , Receptores de Somatomedina/genética , Receptores de Somatomedina/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/genética , Transplante Heterólogo
18.
J Mol Biol ; 299(2): 537-48, 2000 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-10860757

RESUMO

To determine if variable sequences (spacers) between conserved positions in a sequence motif or pattern share a consensus structure, three-dimensional structures containing PROSITE patterns with spacers of fixed length greater than three residues were analyzed. Structural similarities of a given pattern were evaluated by computing the backbone phi, psi and side-chain chi1 dihedral order parameters. The exact bias information in analyzing the conformational variability of the patterns was taken into account by introducing a new parameter, the bias coefficient, which describes the number and distribution of residue types found at each position of a pattern in the structures. The results of the analyses show that backbone conformational heterogeneity at a given position in a sequence motif does not necessarily correlate with the residue-type variability at that position, and the long spacer region can adopt a well-defined backbone conformation, in addition to the conserved residues. Furthermore, a PROSITE pattern may be redefined to yield two or more "refined" regular expressions, each corresponding to a distinct backbone conformation. A way in which the observed structural consensus in a pattern may be employed to improve the accuracy of function prediction from sequence is suggested.


Assuntos
Biologia Computacional/métodos , Reconhecimento Automatizado de Padrão , Proteínas/química , Proteínas/metabolismo , Software , Motivos de Aminoácidos , Animais , Viés , Sítios de Ligação , Domínio Catalítico , Sequência Consenso , Sequência Conservada , Bases de Dados Factuais , Ligantes , Conformação Proteica , Sensibilidade e Especificidade , Relação Estrutura-Atividade
19.
Br J Pharmacol ; 172(1): 214-34, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25220225

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to determine the potency and molecular mechanism of action of YM155, a first-in-class survivin inhibitor that is currently under phase I/II clinical investigations, in various drug-resistant breast cancers including the oestrogen receptor positive (ER(+) ) tamoxifen-resistant breast cancer and the caspase-3-deficient breast cancer. EXPERIMENTAL APPROACH: The potency of YM155 in SK-BR-3, MDA-MB-231, MCF7 and its tamoxifen-resistant sublines, TamR6, TamR7, TamR8, TamC3 and TamC6, were determined by MTT assay. Western blot analysis, flow cytometric analysis, reverse transcription-PCR, fluorescent microscopy and comet assay were used to determine the molecular mechanism of action of YM155 in different breast cancer cell lines. KEY RESULTS: YM155 was equally potent towards the parental ER(+) /caspase-3-deficient MCF7 breast cancer cells and its tamoxifen-resistant sublines in vitro. The ER(-) /HER2(+) SK-BR-3 breast cancer cells and the triple-negative/caspase-3-expressing metastatic aggressive MDA-MB-231 breast cancer cells were also sensitive to YM155 with IC50 values in the low nanomolar range. Targeting survivin by YM155 modulated autophagy, induced autophagy-dependent caspase-7 activation and autophagy-dependent DNA damage in breast cancer cells. Interestingly, YM155 also induced XIAP degradation and the degradation of XIAP might play an important role in YM155-induced autophagy in breast cancer cells. CONCLUSIONS AND IMPLICATIONS: YM155 is a potent survivin inhibitor that has potential for the management of various breast cancer subtypes regardless of the expression of ER, HER2 and caspase-3. Importantly, this study provides new insights into YM155's molecular mechanism of action and therapeutic potential in the treatment of tamoxifen-resistant breast cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Dano ao DNA , Imidazóis/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Naftoquinonas/farmacologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Autofagia/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose/genética , L-Lactato Desidrogenase/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , RNA Interferente Pequeno/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Survivina
20.
Hum Gene Ther ; 10(17): 2727-40, 1999 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-10584920

RESUMO

DNA vaccination is an attractive approach for tumor immunotherapy because of its stability and simplicity of delivery. Advances demonstrate that helper T cell responses play a critical role in initiating immune responses. The aim of the current study is to test whether targeting HPV-16 E7 to the endosomal/lysosomal compartment can enhance the potency of DNA vaccines. We linked the lysosome-associated membrane protein 1 (LAMP-1) to HPV-E7 to construct a chimeric DNA, Sig/E7/LAMP-1 DNA. For in vivo tumor prevention experiments, mice were vaccinated with E7 DNA or Sig/E7/LAMP-1 DNA via gene gun, followed by tumor challenge. For in vivo tumor regression experiments, mice were first challenged with tumor cells and then vaccinated with E7-DNA or Sig/E7/LAMP-1 DNA. Intracellular cytokine staining with flow cytometry analysis, cytotoxic T lymphocyte (CTL) assays, enzyme-linked immunoabsorbent assay (ELISA), and enzyme-linked immunospot (ELISPOT) assays were used for in vitro E7-specific immunological studies. In both tumor prevention and tumor regression assays, Sig/E7/LAMP-1 DNA generated greater antitumor immunity than did wild-type E7 DNA. In addition, mice vaccinated with Sig/E7/LAMP-1 DNA had greater numbers of E7-specific CD4+ helper T cells, higher E7-specific CTL activity, and greater numbers of CD8+ T cell precursors than did mice vaccinated with Sig/E7 or wild-type E7 DNA. Sig/E7 generated a stronger E7-specific antibody response than did Sig/E7/LAMP-1 or wild-type E7 DNA. Our results indicate that linkage of the antigen gene to an endosomal/lysosomal targeting signal may greatly enhance the potency of DNA vaccines.


Assuntos
Neoplasias Experimentais/terapia , Proteínas Oncogênicas Virais/genética , Vacinas de DNA/uso terapêutico , Animais , Antígenos CD/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Endossomos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Proteínas de Membrana Lisossomal , Lisossomos/imunologia , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/virologia , Proteínas Oncogênicas Virais/imunologia , Proteínas E7 de Papillomavirus , Sinais Direcionadores de Proteínas/genética , Vacinas de DNA/genética , Vacinas de DNA/imunologia
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