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1.
Oncogene ; 37(5): 673-686, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29035390

RESUMO

Urothelial carcinoma (UC) carcinogenesis has been hypothesized to occur through epigenetic repression of tumor-suppressor genes (TSGs). By quantitative real-time polymerase chain reaction array, we found that one potential TSG, angiopoietin-like 4 (ANGPTL4), was expressed at very low levels in all bladder cancer cell lines we examined. Previous studies had demonstrated that ANGPTL4 is highly expressed in some cancers, but downregulated, by DNA methylation, in others. Consequently, owing to these seemingly conflicting functions in distinct cancers, the precise role of ANGPTL4 in the etiology of UC remains unclear. In this study, using methylation-specific PCR and bisulfite pyrosequencing, we show that ANGPTL4 is transcriptionally repressed by DNA methylation in UC cell lines and primary tumor samples, as compared with adjacent noncancerous bladder epithelium. Functional studies further demonstrated that ectopic expression of ANGPTL4 potently suppressed UC cell proliferation, monolayer colony formation in vitro, and invasion, migration, and xenograft formation in vivo. Surprisingly, circulating ANGPTL4 was significantly higher in plasma samples from UC patients than normal control, suggesting it might be secreted from other cell types. Interestingly, our data also indicated that exogenous cANGPTL4 could promote cell proliferation and cell migration via activation of signaling through the Erk/focal adhesion kinase axis. We further confirmed that mouse xenograft tumor growth could be promoted by administration of exogenous cANGPTL4. Finally, immunohistochemistry demonstrated that ANGPTL4 was downregulated in tumor cells but overexpressed in tumor adjacent stromal tissues of muscle-invasive UC tissue samples. In conclusion, our data support dual roles for ANGPTL4 in UC progression, either as a tumor suppressor or oncogene, in response to microenvironmental context.


Assuntos
Proteína 4 Semelhante a Angiopoietina/genética , Carcinoma de Células de Transição/genética , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica/genética , Microambiente Tumoral , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Proteína 4 Semelhante a Angiopoietina/sangue , Proteína 4 Semelhante a Angiopoietina/metabolismo , Animais , Carcinogênese/genética , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Cistectomia , Metilação de DNA/genética , Regulação para Baixo , Feminino , Genes Supressores de Tumor , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Oncogenes/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Plant Dis ; 97(9): 1132-1136, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30722420

RESUMO

Guava wilt, caused by Nalanthamala psidii, has become an important disease of guava (Psidium guajava) in Taiwan since the 1970s. This study was conducted to develop a semiselective medium for detecting N. psidii in soil and in tissues of diseased guava trees. Among 9 carbon and 21 nitrogen compounds tested in a modified Czapek-Dox medium, the most effective carbon and nitrogen sources for mycelial growth of N. psidii were sucrose and glycine, respectively. Among eight fungicides tested, iprodione at 5 µg ml-1 and azoxystrobin at 1 µg ml-1 were the most effective fungicides for detection of N. psidii in artificially infested soil or in naturally infected guava debris. Based on the requirement for carbon and nitrogen sources and response to fungicides, a semiselective medium designated as modified sucrose-glycine semiselective medium (mSGSSM) was developed for isolation of N. psidii, using the modified Czapek-Dox medium containing 3% sucrose, 0.3% glycine, iprodione at 5 µg ml-1, azoxystrobin at 1 µg ml-1, streptomycin at 200 µg ml-1, and neomycin at 200 µg ml-1. Colonies of N. psidii on mSGSSM at 30°C for 5 to 10 days were white to orange with sparse aerial hyphae. N. psidii was detected more accurately and efficiently on mSGSSM than on other media, including potato dextrose agar, modified Nash-Snyder medium, and modified Czapek-Dox medium. This semiselective medium is effective in detection of N. psidii from various parts of diseased guava trees and in soil; therefore, it would be a useful medium for etiological, ecological, and epidemiological studies of guava wilt.

3.
Nano Lett ; 10(10): 3984-9, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20809607

RESUMO

Forming functional circuit components in future nanotechnology requires systematic studies of solid-state chemical reactions in the nanoscale. Here, we report efficient and unique methods, point and line contact reactions on Si nanowires, fabricating high quality and quantity of multiple nanoheterostructures of NiSi/Si and investigation of NiSi formation in nanoscale. By using the point contact reaction between several Ni nanodots and a Si nanowire carried out in situ in an ultrahigh vacuum transmission electron microscopy, multiple sections of single-crystal NiSi and Si with very sharp interfaces were produced in a Si nanowire. Owing to the supply limited point contact reaction, we propose that the nucleation and growth of the sugar cane-type NiSi grains start at the middle of the point contacts between two Ni nanodots and a Si nanowire. The reaction happens by the dissolution of Ni into the Si nanowire at the point contacts and by interstitial diffusion of Ni atoms within a Si nanowire. The growth of NiSi stops as the amount of Ni in the Ni nanodots is consumed. Additionally, without lithography, utilizing the line contact reaction between PS nanosphere-mediated Ni nanopatterns and a nanowire of Si, we have fabricated periodic multi-NiSi/Si/NiSi heterostructure nanonowires that may enhance the development of circuit elements in nanoscale electronic devices. Unlike the point contact reaction, silicide growth starts at the contact area in the line contact reaction; the different silicide formation modes resulting from point and line contact reactions are compared and analyzed. A mechanism on the basis of flux divergence is proposed for controlling the growth of the nano-multiheterostructures.

4.
J Fish Biol ; 76(10): 2521-39, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20557606

RESUMO

The spatial distribution patterns of fish larvae and the relationships with hydrographic conditions in the waters surrounding Taiwan were studied in August 2004 when the south-westerly monsoon prevailed. A total of 6566 fish larvae were identified, belonging to 80 families, 129 genera and 230 species. Cluster analysis revealed two station groups, one associated with the South China Sea Surface Current (SCSSC) and the other with the Kuroshio Current (KC). The SCSSC group was characterized by mostly coastal and neritic species, and the KC group was predominated by oceanic species. Larger fish larvae were generally more abundant in the neritic waters west of Taiwan where the SCSSC prevails than in the waters east of Taiwan where the KC prevails. The combination of chlorophyll a, zooplankton and nitrite best explained the relationship of larval fish distribution and environmental variables, implying that the distribution of fish larvae in summer was closely linked to the food source. The changing of monsoons potentially affects the succession of water masses and the transport and assemblage of fish larvae in this study area.


Assuntos
Biodiversidade , Peixes/classificação , Movimentos da Água , Animais , Análise por Conglomerados , Larva/classificação , Oceano Pacífico , Densidade Demográfica , Análise de Componente Principal , Salinidade , Estações do Ano , Água do Mar/análise , Taiwan , Temperatura
5.
Arch Dis Child Fetal Neonatal Ed ; 93(2): F94-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17768157

RESUMO

BACKGROUND: To date there is no firm conclusion as to the efficacy and safety of ibuprofen compared with indometacin for patent ductus arteriosus (PDA) closure in extremely premature infants. OBJECTIVE: To conduct a randomised controlled trial to better address this problem. METHODS: 119 infants (gestational age < or =28 weeks) with respiratory distress syndrome and PDA confirmed by echocardiography were randomly assigned to receive either indometacin (0.2 mg/kg) or ibuprofen (10 mg/kg), starting at <24 hours of life, followed by half these first doses within 48 hours at 24-hour intervals if indicated by echocardiographic PDA flow pattern. RESULTS: The PDA closure rate and the doses of drug (mean (SD)) were similar in both groups: 53/60 (88.3%) and 1.9 (1.5) mg/kg in infants given ibuprofen, and 52/59 (88.1%) and 1.9 (1.7) mg/kg in infants given indometacin. No significant difference was found in the numbers of infants requiring surgical ligation, and the levels of post-treatment serum creatinine and urea nitrogen between the two groups. Although not significantly different, more infants (9/59 (15.3%)) treated with indometacin tended to develop oliguria (<1 ml/kg/h) than those treated with ibuprofen (4/60 (6.7%)). There were no significant differences in side effects or complications between the two groups. CONCLUSIONS: Ibuprofen is as effective as indometacin for the early-targeted PDA treatment in extremely premature infants, without increasing the incidence of complications. When the echocardiographic PDA flow pattern was used as a guide for PDA treatment, fewer doses of drugs were needed to achieve acceptable closing rates.


Assuntos
Inibidores de Ciclo-Oxigenase/administração & dosagem , Permeabilidade do Canal Arterial/tratamento farmacológico , Ibuprofeno/administração & dosagem , Indometacina/administração & dosagem , Doenças do Prematuro/tratamento farmacológico , Análise de Variância , Inibidores de Ciclo-Oxigenase/efeitos adversos , Relação Dose-Resposta a Droga , Permeabilidade do Canal Arterial/diagnóstico por imagem , Feminino , Humanos , Ibuprofeno/efeitos adversos , Indometacina/efeitos adversos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico por imagem , Masculino , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia
6.
Immunohematology ; 18(1): 19-22, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-15373571

RESUMO

An 18-month-old male was admitted to a hospital with a hemoglobin of 4.1 g/dL and a reticulocyte count of 53 percent. There was no history of prior transfusion. Serologic evaluation revealed the presence of both a positive direct antiglobulin test (DAT) and an indirect antiglobulin test (IAT). The patient's red blood cells (RBCs) typed as group A, C-D-E-c+e+ (cde/cde). Evaluation of the IAT revealed the presence of anti-c and anti-E. All other major antibodies were ruled out. Upon adsorption of the patient's serum with ficin-treated Cde/Cde RBCs, both antibody specificities were adsorbed; however, the antibodies were not adsorbed with native (untreated) Cde/Cde RBCs. Furthermore, the autoantibody was not adsorbed by Rhnull cells, thereby suggesting Rh specificity. The serum was incompatible with cde/cde RBCs and compatible with Cde/Cde RBCs. The patient was successfully transfused with Cde/Cde RBCs followed by resolution of his anemia, as evidenced by an increased and stable hemoglobin. It was concluded that the autoantibody had mimicking anti-c and -E specificities. This is a report of an unusual case of autoimmune hemolytic anemia because the Rh autoantibody appeared to have dual mimicking specificities, and the patient's RBCs were antigen negative for one of the antibody specificities, i.e., anti-E.

7.
IUBMB Life ; 50(2): 91-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11185964

RESUMO

alpha-N-Acetylgalactosaminidase from Clostridium perfringens is an exoglycosidase that degrades the human blood type A epitope. A highly purified preparation of alpha-N-acetylgalactosaminidase was obtained from C. perfringens by salt precipitation, gel filtration, ion-exchange chromatography, chromatofocusing, and high-pressure liquid chromatography. The final preparation was homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with a molecular mass of 72.1 kDa. The enzyme was highly selective for terminal N-acetyl-alpha-D-galactosamine residues. No other substantial glycosidase activities, specifically neuraminidase, were detected. The pH optimum of the enzyme was between 6.5 and 7.0, and activity was unaffected by ionic strength. No protease activity was detected and enzyme activity was stable at 4 degrees C for 12 months. ELISA experiments demonstrated activity against blood type A epitope.


Assuntos
Clostridium perfringens/enzimologia , Hexosaminidases/química , Hexosaminidases/isolamento & purificação , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos , Concentração de Íons de Hidrogênio , Íons , Focalização Isoelétrica , Sais/metabolismo , alfa-N-Acetilgalactosaminidase
8.
Br J Radiol ; 71(852): 1313-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10319008

RESUMO

We report an extremely rare case of Ewing's sarcoma (ES) of the humerus in a Chinese neonate. Plain radiography and magnetic resonance imaging showed extensive neoplastic involvement of the humeral diaphysis and adjacent soft tissues, confirmed on histology and immunohistochemistry as being due to ES. This is the first report of congenital ES in a long bone. Since ultrasound at 20 weeks gestation showed a normal fetal skeleton, the ES may have begun to develop in the late middle or third trimester.


Assuntos
Neoplasias Ósseas/congênito , Úmero , Sarcoma de Ewing/congênito , Neoplasias Ósseas/diagnóstico , Feminino , Seguimentos , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Sarcoma de Ewing/diagnóstico
9.
Endoscopy ; 28(2): 244-8, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8739741

RESUMO

BACKGROUND AND STUDY AIMS: The aim of the present study was to review endoscopic findings, treatment, and clinical outcomes in patients with severe upper gastrointestinal bleeding due to tumors. PATIENTS AND METHODS: A retrospective analysis was made of prospectively gathered data on all patients with severe upper gastrointestinal bleeding who were admitted to two large referral centers during a 45-month period. RESULTS: Nine hundred thirty-five patients had severe upper gastrointestinal bleeding, of whom 42 (5%) were found to have tumors. Histologically, nearly all of the tumors were of a malignant type. Fifty-two percent of the patients had acute severe upper gastrointestinal bleeding as the initial presentation of their tumor. The most common tumor was gastric adenocarcinoma, and all of these cases were at advanced stages. Endoscopic hemostasis with thermal probes or epinephrine injection, or both, was carried out in seven patients (17%), with successful hemostasis in all of the tumors. Regardless of the treatment given, patients with upper gastrointestinal tumor bleeding, had a 30-day surgery rate of 43%, a 30-day rebleed rate of 33%, a 30-day mortality rate of 10%, and a 1-year mortality rate of 89%. CONCLUSIONS: Most tumors that cause severe upper gastrointestinal bleeding are of a malignant histologic type and are already at an advanced stage. Endoscopic hemostasis of bleeding upper gastrointestinal tumors is safe and initially effective, and may provide time for elective surgical palliation. Regardless of therapy, upper gastrointestinal tumors with severe bleeding have a poor one-year survival.


Assuntos
Endoscopia do Sistema Digestório , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Neoplasias Gastrointestinais/diagnóstico , Hemostase Endoscópica/métodos , Feminino , Hemorragia Gastrointestinal/etiologia , Neoplasias Gastrointestinais/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
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