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1.
BMC Vet Res ; 18(1): 428, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36482409

RESUMO

BACKGROUND: Atherosclerosis is a common cardiovascular disease in parrots but the antemortem diagnosis is challenging. In human medicine, computed tomography angiography (CTA) has been used widely for the diagnosis of atherosclerosis. By adjusting the injection rate and total dose of contrast medium, the image quality can be improved. To test the effects of different injection conditions on the image quality of major arteries, 10 African grey parrots (Psittacus erithacus) were used. Three injection rates (0.3, 0.4, 0.5 mL/s) and three doses (740, 370, 222 mg of iodine/bird) were tested while the other variables of the studies were fixed. RESULT: A higher injection dose led to a significantly higher attenuation, image noise and diameter, with a lower signal-to-noise ratio and contrast-to-noise ratio of the six major arteries. The 370 mg of iodine/bird group showed significantly better subjective image quality. Furthermore, with increasing injection rates, the prevalence of heterogeneity decreased. However, we found an increased risk of injection failure for the 0.5 mL/s groups. CONCLUSION: We recommend a combination of 370 mg of iodine/bird with 0.4 mL/s for clinical use to achieve better image quality for CTA.


Assuntos
Angiografia por Tomografia Computadorizada , Iodo , Animais , Humanos , Angiografia por Tomografia Computadorizada/veterinária
2.
Parasitol Res ; 120(5): 1627-1636, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33792812

RESUMO

Paragonimus proliferus, a lung fluke of the genus Paragonimus, was first reported in Yunnan province, China. P. proliferus can infect Sprague-Dawley (SD) rats and cause lung damage, but there is still no direct evidence of human infection. Until now, there has been a lack of studies on P. proliferus parasitism and development in mammalian lung tissue. The aim of this study was to perform transcriptomic profiling of P. proliferus at different developmental stages. SD rats were infected with P. proliferus metacercariae obtained from crabs; worms isolated from the lungs at different time points as well as metacercariae were subjected to whole transcriptome sequencing. Overall, 34,403 transcripts with the total length of 33,223,828 bp, average length of 965 bp, and N50 of 1833 bp were assembled. Comparative analysis indicated that P. proliferus, similar to other Paragonimus spp., expressed genes related to catabolism, whereas P. proliferus-specific transcripts were related to the maintenance of cellular redox homeostasis, sensitivity to bacteria, and immune response. Transcriptional dynamics analysis revealed that genes involved in the regulation of catabolism and apoptosis had stable expression over the P. proliferus life cycle, whereas those involved in development and immune response showed time-dependent changes. High expression of genes associated with immune response corresponded to that of genes regulating the sensitivity to bacteria and immune protection. We constructed a P. proliferus developmental model, including the development of the body, suckers, blood cells, reproductive and tracheal systems, lymph, skin, cartilage, and other tissues and organs, and an immune response model, which mainly involved T cells and macrophages. Our study provides a foundation for further research into the molecular biology and infection mechanism of P. proliferus.


Assuntos
Pulmão/parasitologia , Paragonimíase/patologia , Paragonimus/embriologia , Paragonimus/crescimento & desenvolvimento , Animais , Braquiúros/parasitologia , China , Perfilação da Expressão Gênica , Humanos , Estágios do Ciclo de Vida , Metacercárias/crescimento & desenvolvimento , Paragonimíase/parasitologia , Paragonimus/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Transcriptoma/genética
3.
J Cell Sci ; 127(Pt 17): 3735-44, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24994936

RESUMO

Epithelial-mesenchymal transition (EMT) is a developmental program that is associated with esophageal squamous cell carcinoma (ESCC) progression and metastasis. Recently, C/EBPß has been reported to be an EMT inducer in cancer. However, the detailed molecular mechanisms remain unclear. Here, we report for the first time, that the truncated CCAAT-enhancer-binding protein ß (C/EBPß) LIP isoform is abnormally overexpressed and correlated with cancer metastasis in clinical specimens of human ESCC. Furthermore, we demonstrate that C/EBPß LIP mediates epithelial growth factor (EGF)-induced EMT and increases migration and invasion of esophageal cancer cells in a manner that is dependent on miR-203 inactivation. Finally, we identified miR-203 as a direct target of C/EBPß LIP. Disruption of C/EBPß LIP attenuated the EGF-mediated decrease in miR-203, whereas overexpression of C/EBPß LIP alone markedly suppressed miR-203. In addition, we demonstrated that C/EBPß LIP inhibited miR-203 transcription by directly interacting with a conserved distal regulatory element upstream of the miR-203 locus, and in doing so, orchestrated chromatin remodeling. In conclusion, our results have revealed a new regulatory mechanism that involves C/EBPß-LIP-mediated downregulation of miR-203, which plays a key role in EMT and metastasis.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/genética , Carcinoma de Células Escamosas/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Carcinoma de Células Escamosas do Esôfago , Humanos
4.
Phys Rev Lett ; 117(6): 067001, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27541474

RESUMO

We report on the observation of high-temperature (T_{c}) superconductivity and magnetic vortices in single-unit-cell FeSe films on anatase TiO_{2}(001) substrate by using scanning tunneling microscopy. A systematic study and engineering of interfacial properties has clarified the essential roles of substrate in realizing the high-T_{c} superconductivity, probably via interface-induced electron-phonon coupling enhancement and charge transfer. By visualizing and tuning the oxygen vacancies at the interface, we find their very limited effect on the superconductivity, which excludes interfacial oxygen vacancies as the primary source for charge transfer between the substrate and FeSe films. Our findings have placed severe constraints on any microscopic model for the high-T_{c} superconductivity in FeSe-related heterostructures.

5.
Phys Rev Lett ; 115(23): 237002, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26684137

RESUMO

Understanding the mechanism of high transition temperature (T{c}) superconductivity in cuprates has been hindered by the apparent complexity of their multilayered crystal structure. Using a cryogenic scanning tunneling microscopy (STM), we report on layer-by-layer probing of the electronic structures of all ingredient planes (BiO, SrO, CuO{2}) of Bi{2}Sr{2}CaCu_2}O{8+δ} superconductor prepared by argon-ion bombardment and annealing technique. We show that the well-known pseudogap (PG) feature observed by STM is inherently a property of the BiO planes and thus irrelevant directly to Cooper pairing. The SrO planes exhibit an unexpected van Hove singularity near the Fermi level, while the CuO{2} planes are exclusively characterized by a smaller gap inside the PG. The small gap becomes invisible near T{c}, which we identify as the superconducting gap. The above results constitute severe constraints on any microscopic model for high T{c} superconductivity in cuprates.

6.
Biochem Biophys Res Commun ; 446(1): 267-71, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24589738

RESUMO

Recent clinical study indicated that up-regulation of miR-146b was associated with poor overall survival of patients in esophageal squamous cell carcinoma. However, the underlying mechanism of miR-146b dysregulation remains to be explored. Here we report that miR-146b promotes cell proliferation and inhibits cell apoptosis in esophageal cancer cell lines. Mechanismly, two C/EBPß binding motifs are located in the miR-146b promoter conserved region. Among the three isoforms of C/EBPß, C/EBPß LAP2 positively regulated miR-146b expression and increases miR-146b levels in a dose-dependent manner through transcription activation of miR-146b gene. Together, these results suggest a miR-146b regulatory mechanism involving C/EBPß, which may contribute to the up-regulation of miR-146b in esophageal squamous cell carcinoma.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose , Sequência de Bases , Sítios de Ligação/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Sequência Conservada , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica , Humanos , Regiões Promotoras Genéticas , Isoformas de Proteínas/metabolismo , Ativação Transcricional , Regulação para Cima
7.
Artigo em Inglês | MEDLINE | ID: mdl-38692942

RESUMO

The objective of this clinical retrospective study was to analyze the prevalence and distribution of different avian and exotic animals presented to 2 exotics-only veterinary hospital in Hong Kong and Taiwan over a 1 year period. Exotic companion mammals, predominated by rabbits (Oryctolagus cuniculus) that were often diagnosed with fractures, were the most commonly presented group of patients in the hospital in Hong Kong while second most of that in Taiwan, with dental disease being commonly presented in the species. This study provided a general overview of avian and exotic patients presented to exotics-only practices in the East Asia region.

8.
Acta Parasitol ; 67(1): 316-321, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34417714

RESUMO

PURPOSE: To perform environmental sampling and molecular identification of Paragonimus in endemic regions, which may help in minimizing transmission among humans. METHODS: Mountain crabs from the genus Potamiscus were collected and the encysted metacercariae were extracted and subjected to morphological identification, followed by animal inoculation in Sprague-Dawley (SD) rats. After 112 days of infection, animals were killed and adult worms were extracted from lungs and muscles. The morphology of adult worms was characterized by microscopy and molecular identification was done by polymerase chain reaction, followed by sequencing of cox1 and ITS2 genes. Phylogenetic analysis was done by maximum parsimony method. RESULTS: A total of 447 crabs were captured from the streams of Tongchang Town, Jinping County, Yunnan Province, China. The infection rate was found to be 41% (186 out of 447 crabs). The metacercariae of Paragonimus skrjabini was identified by the characteristics round or spherical encysted form measuring 410 to 460 × 400 to 460 µm. After animal infection in SD rats, adults were presumptively confirmed to be P. skrjabini, which was also confirmed by gene amplification and sequence analysis of cox1 and ITS2 regions. Paragonimus skrjabini clustered with previously reported P. skrjabini from Yunnan and Vietnam. The confidence values of their branches were > 95%. Phylogenetic analysis of the ITS2 region revealed two distinct clusters with distinct geographical grouping. Phylogenetic analysis with the combined data sets reiterated the geographical grouping with P. skrjabini from Yunnan clustering with strains from Vietnam. CONCLUSION: Metacercariae of P. skrjabini was discovered in freshwater crabs in Yunnan province, China, and the strains were phylogenetically related to P. skrjabini from Vietnam.


Assuntos
Paragonimíase , Paragonimus , Animais , China/epidemiologia , Paragonimíase/epidemiologia , Paragonimíase/veterinária , Paragonimus/anatomia & histologia , Paragonimus/genética , Filogenia , Ratos , Ratos Sprague-Dawley
9.
Animals (Basel) ; 11(12)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34944256

RESUMO

A sub-adult green sea turtle (Chelonia mydas) was rescued and treated for carapace and plastron shell fractures. The turtle was kept dry-docked for the first 2 months with a placement of a long-term jugular central venous catheter (CVC). Pain management, aggressive antibiotic and anthelmintic therapy, fluid therapy, force feeding, and wound debridement were provided to manage the shell fractures and control bacteremia. Human albumin was administered to treat severe hypoalbuminemia. On day 59, small budding yeasts were noted on the blood smears. Candidemia was confirmed by blood culture, as the yeasts were identified as Candida palmioleophila by the molecular multi-locus identification method. The CVC was removed, and the patient was treated with itraconazole. Although the carapace and plastron wounds had epithelized by 5.5 months after the rescue, the turtle died unexpectedly by 7.5 months. The postmortem examination revealed numerous necrogranulomas with intralesional yeasts, morphologically compatible with Candida spp., in joints, bones, brain, and lungs, suggestive of disseminated candidiasis. We describe a rare case of candidemia in the veterinary field. To our knowledge, this is the first report of candidiasis caused by C. palmioleophila in a reptile. The present results should improve veterinary medical care and, therefore, enhance the conservation of endangered sea turtle species.

10.
J Trop Med ; 2021: 5646291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003270

RESUMO

Paragonimus species are highly prevalent in various regions of China. The study's objective is to isolate and identify Paragonimus from natural habitats and compare the phylogenetic diversity of Paragonimus in southern Yunnan province, China. Metacercariae of Paragonimus was isolated from crabs, and morphologic identification was performed by microscopy. Metacercariae were injected into experimental Paragonimus free Sprague Dawley rats. After 114 days, adult worms and eggs were isolated from multiple organs. Morphologic identification confirmed the initial identification. DNA was extracted from 5 adult worms, and molecular characterization was performed by amplification and sequencing of CO1 and ITS2 regions, followed by phylogenetic analysis. Out of 447 crabs captured, 186 crabs were found to be infected. A total of 4 species of Paragonimus was observed from naturally infected crabs. Paragonimus microrchis (2), Paragonimus heterotremus (1), Paragonimus proliferus (1), and Paragonimus skrjabini (1) were isolated and identified. A total of 32 sequences were downloaded from the National Center for Biotechnology Information, and 5 sequences generated in the study were used for phylogenetic analysis. In the phylogenetic tree of the CO1 gene, Paragonimus proliferus, Paragonimus heterotremus, and Paragonimus skrjabini were clustered with the same species, and the confidence values of their branches were >95%. A congruent phylogenetic relationship was observed with the ITS2 phylogenetic tree. In the phylogenetic tree constructed with the combined dataset of CO1 and ITS2 datasets, Paragonimus proliferus, Paragonimus heterotremus, and Paragonimus skrjabini clustered with the same species, and their branch confidence values were >94%. Paragonimus microrchis clustered with Paragonimus bangkokensis in both datasets. Phylogenetic analysis revealed robustness of the double loci method as against the single-locus method with either CO1 or ITS2 alone. Paragonimus species isolated from the southern Yunnan province, China, was phylogenetically diverse, and the analysis revealed the clustering of multiple species of Paragonimus isolated from different geographic locations.

11.
J Cardiothorac Surg ; 16(1): 28, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741016

RESUMO

OBJECTIVE: To summarize the clinical characteristics of adult cases of paragonimiasis with lung masses as the main manifestation in Xishuangbanna, Yunnan Province, analyze the causes of misdiagnosis, and improve the levels of clinical diagnosis and treatment. METHOD: We conducted a retrospective analysis of the clinical data and diagnosis and treatment of 8 adult cases of paragonimiasis with lung masses as the main manifestation that were diagnosed in the Oncology Department of People's hospital of Xishuangbanna Dai Autonomous Prefecture from July 2014 to July 2019. RESULT: All 8 patients were from epidemic paragonimiasis areas and had a confirmed history of consuming uncooked freshwater crabs. The clinical manifestations were mainly fever, dry cough, and chest pain. The disease durations were long, and peripheral blood eosinophil counts were elevated. The cases had been misdiagnosed as pneumonia or pulmonary tuberculosis. After years of anti-inflammatory or anti-tuberculosis treatment, the symptoms had not improved significantly. Patients eventually sought treatment from the oncology department for hemoptysis. Chest computed tomography showed patchy consolidation in the lungs, with nodules, lung masses, and enlarged mediastinal lymph nodes. CONCLUSION: Paragonimiasis is a food-borne parasitic disease. Early clinical manifestations and auxiliary examination results are nonspecific. The parasite most often invades the lungs, and the resulting disease is often misdiagnosed as pneumonia, pulmonary tuberculosis, or lung cancer (Acta Trop 199: 05074, 2019). To avoid misdiagnosis, clinicians should inquire, in detail, about residence history and history of unclean food and exposure to infected water and make an early diagnosis based on the inquired information and imaging examination results. For patients who have been diagnosed with pneumonia or pulmonary tuberculosis and whose symptoms do not improve significantly after anti-inflammatory or anti-tuberculosis treatments, their epidemiological history should be traced to further conduct differential diagnosis and avoid misdiagnosis.


Assuntos
Pneumopatias Parasitárias/diagnóstico , Pulmão/diagnóstico por imagem , Paragonimíase/diagnóstico , Animais , Anticorpos Anti-Helmínticos/análise , China/epidemiologia , DNA de Helmintos/análise , Diagnóstico Diferencial , Erros de Diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Incidência , Pulmão/parasitologia , Pneumopatias Parasitárias/epidemiologia , Pneumopatias Parasitárias/parasitologia , Masculino , Pessoa de Meia-Idade , Paragonimíase/tratamento farmacológico , Paragonimíase/parasitologia , Paragonimus/genética , Paragonimus/imunologia , Estudos Retrospectivos , Tórax/patologia , Tomografia Computadorizada por Raios X
12.
Zool Res ; 41(5): 564-568, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32738109

RESUMO

Osteonecrosis is a common human disease in orthopedics. It is difficult to treat, and half of patients may need artificial joint replacement, resulting in a considerable economic burden and a reduction in quality of life. Hormones are one of the major causes of osteonecrosis and high doses of corticosteroids are considered the most dangerous factor. Because of the complexity of treatment, we still need a better animal model that can be widely used in drug development and testing. Tree shrews are more closely related to primates than rodents. As such, we constructed a successful tree shrew model to establish and evaluate steroid-associated osteonecrosis (SAON). We found that low-dose lipopolysaccharide (LPS) combined with high-dose methylprednisolone (MPS) over 12 weeks could be used to establish a tree shrew model with femoral head necrosis. Serum biochemical and histological analyses showed that an ideal model was obtained. Thus, this work provides a useful animal model for the study of SAON and for the optimization of treatment methods.


Assuntos
Lipopolissacarídeos/toxicidade , Metilprednisolona/toxicidade , Osteonecrose/induzido quimicamente , Tupaiidae , Corticosteroides , Animais , Modelos Animais de Doenças , Glucocorticoides/administração & dosagem , Glucocorticoides/toxicidade , Lipopolissacarídeos/administração & dosagem , Metilprednisolona/administração & dosagem
13.
Biochim Biophys Acta ; 1783(10): 1803-14, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18619497

RESUMO

CCAAT/Enhancer binding proteins (C/EBPs) and peroxisome proliferator-activated receptors gamma (PPARG) play critical roles in the regulation of lipid metabolism genes. Overexpression of CEBPdelta (CEBPD) enhances lipid accumulation and specifically activates PPARG2 transcription in HepG2 cells. By using 5'-serial deletion reporter analysis, we show that the region comprising the -457 to +129 base pairs is required for CEBPD response of the PPARG2 promoter. Two critical CEBPD-binding motifs on the -324/-311 and -158/-145 of human PPARG2 promoter are identified. We previously have shown that the human CEBPD is sumoylated by small ubiquitin-related modifier-1 (SUMO1). We further demonstrated that the sumoylation of CEBPD lysine 120 is also detectable in HepG2 cells, and this modification functions for binding of the recruits, HDAC1 and HDAC3. Meanwhile, an in vivo chromatin IP assay demonstrated that the sumoylation mutant of CEBPD lost a significant portion of HDAC1 and HDAC3 interaction. Combining that the increasing amount of CEBPD and the sumoylated CEBPD (suCEBPD) consistently responded to lipogenic stimulation, these results suggest that the excess non-sumoylated CEBPD could be a critical activator which reverses suCEBPD/HDAC1/HDAC3-mediated PPARG2 gene inactivation and promotes hepatic lipogenesis. Taken together, we suggest that suCEBPD/HDAC1/HDAC3 complex inactivates PPARG2 transcription, and the induction of CEBPD expression transiently activates PPARG2 transcription which is involved in adipocyte-like lipogenesis in HepG2 cells.


Assuntos
Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Histona Desacetilases/metabolismo , Lipogênese , Fígado/metabolismo , PPAR gama/metabolismo , Proteína SUMO-1/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 1 , Histona Desacetilases/genética , Humanos , PPAR gama/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , Transcrição Gênica/genética
14.
Am J Cardiol ; 102(5): 518-23, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18721505

RESUMO

Exercise treadmill testing (ETT) is a well-accepted examination for patients with suspected coronary artery disease (CAD), and exercise induced ST-segment deviation is commonly used for CAD detection. However, recent evidence shows that systolic blood pressure (SBP) changes during and after exercise were associated with CAD severity, risk of acute myocardial infarction and stroke, new-onset hypertension, and even cardiovascular mortality. We retrospectively assessed 3,054 patients referred for ETT in 1996. Blood pressure and heart rate were recorded at rest, during peak exercise, and 1 and 3 min after exercise. SBP at 3 min of recovery equal to or higher than that at 1-min of recovery was defined as paradoxical SBP increase. These patients were categorized into 4 groups according to ETT ST-segment change and postexercise SBP change. After 10 years of follow-up, 346 patients (11%) died, with 129 (4%) dying from cardiovascular disease (CVD). Among the 4 groups, patients with ischemic ST-segment change and paradoxical SBP increase were associated with a higher risk for mortality, with odds ratios of 1.86 (95% confidence interval 1.31 to 2.65) for all-cause mortality and 3.18 (95% confidence interval 1.94 to 5.20) for CVD mortality, respectively. Patients with isolated paradoxical SBP increase still had a higher risk of CVD mortality (odds ratio 1.80, 95% confidence interval 1.70 to 3.04), even after controlling other cardiovascular risk factors. In subgroup analysis of 346 mortality subjects, patients with ischemic ST-segment change and paradoxical SBP increase would be more likely to die from CVD. In conclusion, compared with ischemic ST-segment change, paradoxical SBP increase after exercise is an important and significant predictor of CVD mortality.


Assuntos
Pressão Sanguínea/fisiologia , Teste de Esforço , Hipertensão/fisiopatologia , Isquemia Miocárdica/mortalidade , Causas de Morte/tendências , Intervalos de Confiança , Eletrocardiografia , Feminino , Seguimentos , Humanos , Hipertensão/complicações , Hipertensão/mortalidade , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia , Razão de Chances , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Taiwan/epidemiologia
15.
Nucleic Acids Res ; 34(1): 217-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16397300

RESUMO

NF-IL6beta regulates gene expression and plays function roles in many tissues. The EGF-regulated cyclooxygenase-2 (cox-2) expression is mediated through p38(MAPK) signaling pathway and positively correlates with NF-IL6beta expression in A431 cells. NF-IL6beta coordinated with c-Jun on cox-2 transcriptional activation by reporter and small interfering RNA assays. NF-IL6beta could directly bind to CCAAT/enhancer-binding protein (C/EBP) and cyclic AMP-response element (CRE) sites of the cox-2 promoter by in vitro-DNA binding assay. The C/EBP site was important for basal and, to a lesser extent, for EGF-regulated cox-2 transcription, while the CRE site was a more specific response to EGF inducibility of cox-2 gene. SUMO1 expression attenuated EGF- and NF-IL6beta-induced cox-2 promoter activities. NF-IL6beta was found to be sumoylated by in vivo- and in vitro-sumoylation assays, and the SUMO1-NF-IL6beta (suNF-IL6beta) lost its ability to interact with p300 in in vitro-binding assay. NF-IL6beta was also acetylated by p300, and acetylation of NF-IL6beta enhanced the cox-2 promoter activity stimulated by NF-IL6beta itself. In vivo-DNA binding assay demonstrated that EGF stimulated the recruitment of p300 and NF-IL6beta to the cox-2 promoter, yet promoted the dissociation of SUMO1-modificated proteins from the promoter. These results indicated that NF-IL6beta plays a pivotal role in the regulation of basal and EGF-induced cox-2 transcription.


Assuntos
Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Ciclo-Oxigenase 2/genética , Regulação Enzimológica da Expressão Gênica , Processamento de Proteína Pós-Traducional , Ativação Transcricional , Acetilação , Animais , Sítios de Ligação , Proteína delta de Ligação ao Facilitador CCAAT/fisiologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Ciclo-Oxigenase 2/biossíntese , Fator de Crescimento Epidérmico/antagonistas & inibidores , Histona Acetiltransferases/antagonistas & inibidores , Histona Acetiltransferases/metabolismo , Imidazóis/farmacologia , Regiões Promotoras Genéticas , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Elementos de Resposta , Proteína SUMO-1/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Fatores de Transcrição de p300-CBP , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
16.
Environ Sci Pollut Res Int ; 24(10): 9481-9494, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28236202

RESUMO

To reveal the detailed vertical oxygen distribution at the sediment-water interface (SWI) and its relation with the oxygen consumption processes during and after aeration of polluted urban rivers, experimental systems constructed with collected sediment and in situ overlying water from a polluted urban river were aerated above or beneath the sediment-water interface 12 h a day for 15 days and left nonaerated for the following 10 days. The results showed that aeration of water or sediment both increased dissolved oxygen (DO) concentrations in the SWI, characterized by shifts in a "decrease-increase-decrease" manner during around 3 h for the aeration of water treatment (AW) and 6 h for the aeration of sediment treatment (AS). The oxygen penetration depth for AS experiments was between 0.66 and 4.16 mm with an average of 1.79 mm, significantly higher than that for AW experiments; however, the oxygen dissipation constant (mm-1) measuring the decay rate of DO near the SWI was greater for the AW experiments than the AS experiments. During the 10-day nonaeration period, the accumulation of nitrate in both the overlying water and sediment was greatly increased concomitantly with the higher oxygenation in AS experiments. From the nitrogen removal viewpoint, these results suggest that the SWI needs moderate oxygenation which enables nitrate and nitrite to be removed by denitrification rather than to be totally nitrified and accumulate as would result from the conventional practice by singly elevating DO concentrations.


Assuntos
Oxigênio , Rios , Nitrogênio , Água , Poluentes Químicos da Água , Purificação da Água
17.
Sci Bull (Beijing) ; 62(12): 852-856, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36659319

RESUMO

The search for Majorana fermions in topological superconductors is one of paramount research targets in physics today. Using a cryogenic scanning tunneling microscopy, we here report the signature of topologically nontrivial superconductivity on a single material of ß-Bi2Pd films grown by molecular beam epitaxy. The superconducting gap associated with spinless odd-parity pairing opens on the surface and appears much larger than the bulk one due to the Dirac-fermion enhanced parity mixing of surface pair potential. Zero bias conductance peaks, probably from Majorana zero modes supported by such superconducting states, are identified at magnetic vortices. The superconductivity exhibits resistance to nonmagnetic defects, characteristic of time-reversal-invariant topological superconductors. Our study reveals ß-Bi2Pd as a prime platform to generate, manipulate and braid Majorana zero modes for quantum computation.

18.
Sci Rep ; 7(1): 13043, 2017 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-29026122

RESUMO

Feline infectious peritonitis (FIP), caused by a mutated feline coronavirus, is one of the most serious and fatal viral diseases in cats. The disease remains incurable, and there is no effective vaccine available. In light of the pathogenic mechanism of feline coronavirus that relies on endosomal acidification for cytoplasmic entry, a novel vacuolar ATPase blocker, diphyllin, and its nanoformulation are herein investigated for their antiviral activity against the type II feline infectious peritonitis virus (FIPV). Experimental results show that diphyllin dose-dependently inhibits endosomal acidification in fcwf-4 cells, alters the cellular susceptibility to FIPV, and inhibits the downstream virus replication. In addition, diphyllin delivered by polymeric nanoparticles consisting of poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PEG-PLGA) further demonstrates an improved safety profile and enhanced inhibitory activity against FIPV. In an in vitro model of antibody-dependent enhancement of FIPV infection, diphyllin nanoparticles showed a prominent antiviral effect against the feline coronavirus. In addition, the diphyllin nanoparticles were well tolerated in mice following high-dose intravenous administration. This study highlights the therapeutic potential of diphyllin and its nanoformulation for the treatment of FIP.


Assuntos
Antivirais/farmacologia , Coronavirus Felino/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Nanopartículas/química , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , Animais , Benzodioxóis/farmacologia , Gatos , Linhagem Celular , Modelos Animais de Doenças , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Peritonite Infecciosa Felina/imunologia , Peritonite Infecciosa Felina/virologia , Lignanas/farmacologia , Nanopartículas/ultraestrutura , Polietilenoglicóis/química , ATPases Vacuolares Próton-Translocadoras/metabolismo
19.
J Phys Chem B ; 110(26): 12974-80, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16805602

RESUMO

A rotating electrode was employed to investigate the electrodeposition of Bi2Te3 nanowires. We found that mass transport of electrolytes into alumina templates of high aspect ratio plays a significant role in determining the properties of the obtained wires since diffusion is the rate-determining mechanism of mass transport within these nanochannels. In addition to slow growing rate, the effect of mass transport causes a slight composition variation from the bottom to the top of the wires. With a rotating electrode, the composition variation along the wires can be reduced by shortening the concentration depleted zone from the bulk electrolyte to the opening of pores. The wire growing rate can consequently be increased. Moreover, the wire compositions were confirmed to be adjustable by varying the rotation speed under the limitation of using a thin template.

20.
J Phys Chem B ; 110(32): 15988-93, 2006 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-16898755

RESUMO

Pt-Ru alloy is a bimetallic catalyst most commonly used in the direct methanol fuel cell (DMFC). In this paper, a new process to synthesize an unsupported Pt-Ru colloid has been introduced. The characteristics of synthesized nanoparticles were identified by XRD, TEM/EDX, and SEM, and it shows that Ru atoms are incorporated into the Pt fcc structure and the well-dispersed particles (diameter approximately 4 nm) possess a Pt-rich feature. This catalyst shows a hydrophobic characteristic which can adsorb very well on the hydrophobic-treated carbon paper or carbon cloth without the need of Nafion. Accordingly, this method can avoid particle agglomeration, and the synthesized catalyst demonstrates strong adsorption with carbon paper. In addition, this colloid-type Nafion-free catalyst was measured via linear sweep voltammetry (LSV) and exhibited electrochemical activity for methanol oxidation comparable to the commercial one with Nafion binding.

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