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1.
Cell Tissue Res ; 368(2): 311-323, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28138798

RESUMO

Because hermatypic species use symbiotic algal photosynthesis, most of the literature in this field focuses on this autotrophic mode and very little research has studied the morphology of the coral's digestive system or the digestion process of particulate food. Using histology and histochemestry, our research reveals that Stylophora pistillata's digestive system is concentrated at the corals' peristome, actinopharynx and mesenterial filaments (MF). We used in-situ hybridization (ISH) of the RNA transcript of the gene that codes for the S. pistillata digestive enzyme, chymotrypsinogen, to shed light on the functionality of the digestive system. Both the histochemistry and the ISH pointed to the MF being specialized digestive organs, equipped with large numbers of acidophilic and basophilic granular gland cells, as well as acidophilic non-granular gland cells, some of which produce chymotrypsinogen. We identified two types of MF: short, trilobed MF and unilobed, long and convoluted MF. Each S. pistillata polyp harbors two long convoluted MF and 10 short MF. While the short MF have neither secreting nor stinging cells, each of the convoluted MF display gradual cytological changes along their longitudinal axis, alternating between stinging and secreting cells and three distinctive types of secretory cells. These observations indicate the important digestive role of the long convoluted MF. They also indicate the existence of novel feeding compartments in the gastric cavity of the polyp, primarily in the nutritionally active peristome, in the actinopharynx and in three regions of the MF that differ from each other in their cellular components, general morphology and chymotrypsinogen excretion.


Assuntos
Antozoários/anatomia & histologia , Sistema Digestório/anatomia & histologia , Sequência de Aminoácidos , Animais , Quimotripsinogênio/química , Quimotripsinogênio/metabolismo , Sistema Digestório/citologia , Hibridização In Situ , Alinhamento de Sequência
2.
J Invertebr Pathol ; 129: 13-27, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25958261

RESUMO

In early August 2008, observations by divers indicated that sea fans, particularly Gorgonia ventalina, Gorgonia flabellum, and Iciligorgia schrammi, were being covered by benthic filamentous cyanobacteria. From August 2008 through January 2009 and again in April 2009, tissue samples from a targeted G. ventalina colony affected by cyanobacteria and from a nearby, apparently healthy (without cyanobacteria) control colony, were collected monthly for histopathological examination. The primary cellular response of the sea fan to overgrowth by cyanobacteria was an increase in the number of acidophilic amoebocytes (with their granular contents dispersed) that were scattered throughout the coenenchyme tissue. Necrosis of scleroblasts and zooxanthellae and infiltration of degranulated amoebocytes were observed in the sea fan surface tissues at sites overgrown with cyanobacteria. Fungal hyphae in the axial skeleton were qualitatively more prominent in cyanobacteria-affected sea fans than in controls.


Assuntos
Antozoários/microbiologia , Cianobactérias , Animais , Florida
3.
Phys Rev Lett ; 111(16): 166101, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24182283

RESUMO

We show ferromagnetic properties of hydrogen-functionalized epitaxial graphene on SiC. Ferromagnetism in such a material is not directly evident as it is inherently composed of only nonmagnetic constituents. Our results nevertheless show strong ferromagnetism with a saturation of 0.9µ(B)/hexagon projected area, which cannot be explained by simple magnetic impurities. The ferromagnetism is unique to hydrogenated epitaxial graphene on SiC, where interactions with the interfacial buffer layer play a crucial role. We argue that the origin of the observed ferromagnetism is governed by electron correlation effects of the narrow Si dangling bond states in the buffer layer exchange coupled to localized states in the hydrogenated graphene layer. This forms a quasi-three-dimensional ferromagnet with a Curie temperature higher than 300 K.

4.
Neth Heart J ; 21(9): 391-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23722429

RESUMO

Percutaneous epicardial mapping and ablation is an emerging method to treat ventricular tachycardias (VT), premature ventricular complexes (PVC), and accessory pathways. The use of a remote magnetic navigation system (MNS) could enhance precision and maintain safety. This multiple case history demonstrates the feasibility and safety of the MNS-guided epicardial approach in mapping and ablation of ischaemic VT, outflow tract PVCs, and a left-sided accessory pathway. All patients had previously undergone endocardial mapping for the same arrhythmia. MNS could present an advantage from more precise navigation for mapping and maintaining catheter stability during energy application.

5.
Oncogene ; 30(30): 3328-35, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21399661

RESUMO

Lung cancer is the most common cause of cancer-related mortality worldwide. Here, we report elevated expression of tribbles homolog 2 (TRIB2) in primary human lung tumors and in non-small cell lung cancer cells that express low levels of differentiation-inducing transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα). In approximately 10-20% of cases, elevated TRIB2 expression resulted from gene amplification. TRIB2 knockdown was found to inhibit cell proliferation and in vivo tumor growth. In addition, TRIB2 knockdown led to morphological changes similar to C/EBPα overexpression and correlated with increased expression and activity of C/EBPα. TRIB2-mediated regulation of C/EBPα was found to occur through the association of TRIB2 with the E3 ligase TRIM21. Together, these data identify TRIB2 as a potential driver of lung tumorigenesis through a mechanism that involves downregulation of C/EBPα.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/metabolismo , Camundongos , RNA Interferente Pequeno/genética , Ribonucleoproteínas/metabolismo
6.
Science ; 309(5740): 1570-3, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16141075

RESUMO

Noncoding RNA molecules (ncRNAs) have been implicated in numerous biological processes including transcriptional regulation and the modulation of protein function. Yet, in spite of the apparent abundance of ncRNA, little is known about the biological role of the projected thousands of ncRNA genes present in the human genome. To facilitate functional analysis of these RNAs, we have created an arrayed library of short hairpin RNAs (shRNAs) directed against 512 evolutionarily conserved putative ncRNAs and, via cell-based assays, we have begun to determine their roles in cellular pathways. Using this system, we have identified an ncRNA repressor of the nuclear factor of activated T cells (NFAT), which interacts with multiple proteins including members of the importin-beta superfamily and likely functions as a specific regulator of NFAT nuclear trafficking.


Assuntos
Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas Nucleares/antagonistas & inibidores , Interferência de RNA , RNA não Traduzido/fisiologia , Fatores de Transcrição/antagonistas & inibidores , Animais , Linhagem Celular , Humanos , Camundongos , Fatores de Transcrição NFATC , RNA Longo não Codificante , RNA não Traduzido/antagonistas & inibidores , RNA não Traduzido/genética , beta Carioferinas/metabolismo
7.
Rapid Commun Mass Spectrom ; 15(24): 2387-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11746907

RESUMO

Individual peptides with lysine at the C-terminus as well as protein tryptic digests were reacted with 2-methoxy-4,5-dihydro-1H-imidazole, converting lysine residues to their 4,5-dihydro-1H-imidazol-2-yl derivatives. The mass spectra of derivatized digests exhibit a greater number of more intense features than their underivatized counterparts, thus increasing the information obtained in peptide mapping experiments. Additionally, MS/MS spectra of the derivatized peptides are greatly simplified in comparison to their native species, yielding primarily an easily interpretable series of y-ions. Finally, this novel label also enables differential quantitation studies, as a stable isotopic form containing four deuterium atoms can readily be produced.


Assuntos
Proteínas/química , Sequência de Aminoácidos , Animais , Calibragem , Cavalos , Hidrólise , Imidazóis/química , Indicadores e Reagentes , Lisina/análise , Dados de Sequência Molecular , Mioglobina/análise , Fragmentos de Peptídeos/análise , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Tripsina
8.
Anal Chem ; 73(9): 1987-92, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11354480

RESUMO

Capillaries with inner diameters of 550 microm have successfully been packed with 1.5-microm octadecyl silica particles using frits made of macroporous polymers by the UV photopolymerization of a solution of glycidyl methacrylate and trimethylolpropane trimethacrylate. This type of frit is found superior to one made of low-melting point poly(styrene-co-divinylbenzene) beads. Bubble formation is not observed to occur within these capillary columns under our experimental conditions. Separations can be achieved with sample injection volumes as high as 1 microL. To demonstrate its semipreparative use, a mixture of 500 nL of taxol (20 mM) and its precursor, baccatin III (30 mM), is separated using such a column with a Tris buffer.


Assuntos
Eletroforese Capilar , Taxoides , Alcaloides/química , Alcaloides/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Eletroquímica , Metacrilatos/química , Paclitaxel/química , Paclitaxel/isolamento & purificação , Polímeros/química , Dióxido de Silício/química
9.
Anal Chem ; 72(19): 4614-22, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11028619

RESUMO

Monolithic columns for chiral capillary electrochromatography have been prepared within the confines of untreated fused-silica capillaries in a single step by a simple copolymerization of mixtures of O-[2-(methacryloyloxy)ethylcarbamoyl]-10,11-dihydroquinidine , ethylene dimethacrylate, and glycidyl methacrylate or 2-hydroxyethyl methacrylate in the presence of mixture of cyclohexanol and 1-dodecanol as a porogenic solvent. The porous properties of the monolithic columns can easily be controlled through changes in the composition of the binary porogenic solvent. Although both thermal- and UV light-initiated polymerizations afford useful capillary columns, monoliths prepared using the former approach exhibit better chromatographic properties. The ability to control pore size independently of the polymerization mixture composition enables the preparation of monoliths with varying percentages of the chiral monomer and cross-linker, as well as the optimization of their separation properties. Very good separations of model racemate (R,S)-N-3,5-dinitrobenzoylleucine were achieved using an optimized monolithic CEC column, with high efficiencies of up to 74000 plates/m for the retained peaks.


Assuntos
Cromatografia Líquida , Eletroforese Capilar , Polímeros , Quinidina , Estereoisomerismo
10.
J Chromatogr A ; 887(1-2): 3-29, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10961301

RESUMO

Monolithic columns for capillary electrochromatography (CEC) are receiving quite remarkable attention. Both the simplicity of the in situ preparation and the large number of readily available chemistries make the monolithic separation media a vital alternative to capillary columns packed with particulate materials. This review summarizes the current state-of-the-art in this rapidly growing area of CEC with a focus on monolithic capillary columns prepared from synthetic polymers. Recent achievements in column technologies for both high-performance liquid chromatography and capillary electrophoresis are used as the starting point to highlight the influence of these well established analytical methods on the development of monolithic capillary columns for CEC. The effects of individual variables on the separation properties of monolithic capillaries are discussed in detail. The analytical potential of these columns is demonstrated with separations involving various families of compounds in different chromatographic modes.


Assuntos
Eletroforese Capilar/métodos , Polímeros/química , Géis/química , Porosidade , Solventes/química
11.
Anal Chem ; 70(11): 2288-95, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9624900

RESUMO

Monolithic columns for capillary electrochromatography have been prepared within the confines of untreated fused-silica capillaries in a single step by a simple copolymerization of mixtures of butyl methacrylate, ethylene dimethacrylate, and 2-acrylamido-2-methyl-1-propane-sulfonic acid (AMPS) in the presence of a porogenic solvent. The use of these novel macroporous monoliths eliminates the need for frits, the difficulties encountered with packed capillaries, and capillary surface functionalization. Since the porous properties of the monolithic materials can be easily tailored through changes in the composition of the ternary porogenic solvent, the effects of both pore size and the percentage of sulfonic acid monomer on the efficiency and the electroosmotic flow velocity of the capillary columns could be studied independently over a broad range. A simple increase in the content of charged functionalities within the monolith leads to an expected acceleration of the flow velocity. However, increasing the pore size leads to a substantial deterioration of the efficiency of the separation. In contrast, monoliths with increasing levels of AMPS in which the pore size remains fixed due to adjustments in the composition of the porogenic solvent show no deterioration in efficiency while maintaining the same increase in flow velocity, thus producing a significant reduction in separation time. Additionally, measurements on monoliths with constant levels of AMPS but different pore sizes suggest that flow velocity may be affected by the flow resistance within the capillary column.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Reagentes de Ligações Cruzadas/análise , Reagentes de Ligações Cruzadas/química , Metacrilatos/análise , Metacrilatos/química , Concentração Osmolar , Porosidade , Reprodutibilidade dos Testes , Dióxido de Silício/química , Propriedades de Superfície
12.
Anal Chem ; 70(11): 2296-302, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9624901

RESUMO

The effect of chromatographic conditions on the performance of monolithic poly(butyl methacrylate-co-ethylene dimethacrylate-co-2-acrylamido-2-methyl-1-propanesulfonic acid) columns in capillary electrochromatography has been studied. The flow velocity was found to be proportional to the strength of the electric field and both the pH and the composition of the mobile phase. A column efficiency of 120,000 plates/m at the optimum flow velocity of 1.5 cm/min is achieved for all the monolithic capillary columns of identical composition and porosity, regardless of their length, which varied from 30 to 120 cm. The polymeric separation medium exhibits retention and selectivity properties similar to those of typical ODS packings for reversed-phase chromatography. In addition to the "classical" use of monolithic capillary columns for the electrochromatographic separation of small molecules in reversed-phase mode, larger styrene oligomers were also separated under isocratic elution conditions. In addition, the electroosmotically driven size exclusion chromatography of polystyrene standards with molecular weights up to 10(6) has been demonstrated for the first time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Derivados de Benzeno/isolamento & purificação , Campos Eletromagnéticos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Concentração Osmolar , Polímeros , Poliestirenos/isolamento & purificação , Porosidade , Propriedades de Superfície
13.
Anal Chem ; 69(17): 3646-9, 1997 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9286168

RESUMO

Rigid, monolithic capillary columns for reversed-phase electrochromatography have been prepared within the confines of untreated fused-silica capillaries in a single step by a simple copolymerization of ethylene dimethacrylate, butyl methacrylate, and 2-acrylamido-2-methyl-1-propanesulfonic acid in the presence of a porogenic solvent. The composition of the specifically designed ternary porogenic solvent allows fine control of the porous properties of the monolithic material over a broad range. While the electroosmotic flow through these capillary columns increases with both increasing pore size of the monolith and content of charged functionalities, better chromatographic properties have been observed for monoliths with larger surface area and hydrophobicity. Using this technique, monolithic capillary columns with an efficiency higher than 120000 plates/m have been easily obtained.


Assuntos
Polímeros/química , Cromatografia Líquida de Alta Pressão , Eletroquímica , Eletroforese Capilar , Polímeros/isolamento & purificação , Espectrofotometria Ultravioleta
15.
Am J Dis Child ; 143(10): 1154-61, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2486190

RESUMO

Analyses were undertaken to determine the causes of cerebral palsy in a prospective study of 43,437 full-term children. Presumed causes were found for about 71% of the 34 quadriplegic and 40% of the 116 nonquadriplegic patients with cerebral palsy. Risk estimates based on predictive models, adjusted for multiple factors, suggest that 53% of the quadriplegic patients with cerebral palsy could be attributed to congenital disorders, 14% to birth asphyxia, and 8% to other identified disorders. Thirty-five percent of the nonquadriplegic patients with cerebral palsy could be attributed to congenital disorders and 6% to other disorders. In the victims of cerebral palsy, characteristic consequences of birth asphyxia were more often the result of nonasphyxial disorders. These included meconium in the amniotic fluid, low 10-minute Apgar scores, neonatal apnea spells, seizures, persisting neurologic abnormalities, and slow head growth after birth.


Assuntos
Paralisia Cerebral/etiologia , Idoso , Líquido Amniótico/análise , Índice de Apgar , Asfixia Neonatal/complicações , Doenças do Sistema Nervoso Central/complicações , Criança , Intervalos de Confiança , Anormalidades Congênitas , Humanos , Lactente , Recém-Nascido , Mecônio , Estudos Prospectivos , Fatores de Risco
17.
Am J Dis Child ; 141(1): 50-4, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3788882

RESUMO

We undertook analyses to determine if fetal, intrapartum, and neonatal hypoxia are important causes of low IQ values. We analyzed prospectively collected pregnancy, perinatal, and subsequent developmental data for 19,117 children. As expected, sociohereditary and demographic factors had a large influence on IQ scores. Taking these latter influences into consideration, nothing that happened during labor, delivery, or the neonatal period affected subsequent IQ values. The same was true for early pregnancy disorders that can produce acute fetal hypoxia. By contrast, antenatal disorders and conditions that can produce subacute or chronic fetal hypoxia correlated with low IQ values. These antenatal disorders and conditions were maternal gestational anemia, relative gestational hypotension, hypertension, multiple births, and fetal growth retardation. All of these findings were the same whether neurologic abnormalities were absent or present, suggesting that the same factors were sometimes involved in the genesis of cognitive impairments and neurologic abnormalities.


Assuntos
Hipóxia Fetal , Hipóxia , Inteligência , Criança , Feminino , Hipóxia Fetal/etiologia , Humanos , Hipóxia/etiologia , Testes de Inteligência , Estudos Longitudinais , Complicações do Trabalho de Parto , Gravidez , Complicações na Gravidez , Estudos Prospectivos , Análise de Regressão , Fatores Socioeconômicos
18.
J Natl Cancer Inst ; 76(5): 895-912, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2871213

RESUMO

Colonies of the elkhorn coral (Acropora palmata), possessing raised, whitened, irregularly shaped skeletal protuberances, were discovered at Carysfort Reef and Grecian Rocks, Key Largo National Marine Sanctuary, Key Largo, FL. These lesions exhibited relatively rapid growth and spread along the branches, as polyps were overlaid by coenosteal skeletal material. Histopathological examinations of the soft tissues surrounding and extending into the skeletal masses revealed proliferation of gastrovascular canals and associated calicoblastic epidermis, with loss of normal polyp structures and zooxanthellae. The slightly atypical tumor calicoblasts were cuboidal to columnar, resembling those found in the rapidly growing apical tips. Stable carbon isotope ratios of skeletal samples revealed that the tumor skeleton was isotopically lighter than the skeleton in the normal or apical track regions, indicative of higher tissue metabolic rates and lack of carbon isotope fractionation by zooxanthellae. This condition appears to be a neoplasm of the coral, and it is proposed that it be classified "calicoblastic epithelioma." Several different types of abnormal skeletal deposition, possibly the result of neoplastic processes, have been reported to occur in stony corals and are here reviewed.


Assuntos
Cnidários , Animais , Calcinose/patologia , Cnidários/crescimento & desenvolvimento , Neoplasias/patologia
19.
Obstet Gynecol ; 64(5): 601-7, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6493652

RESUMO

Data were analyzed from a large prospective study to try to determine whether or not women's smoking during pregnancy affects their children's mental development. Many confounding variables were controlled by multiple regression analysis and by intrapair comparisons of siblings whose mothers had smoked during one but not in the other of the two pregnancies. Hyperactivity, short attention span, and lower scores on spelling and reading tests were more frequent for children whose mothers had smoked throughout pregnancy. The cognitive abnormalities were mild, with achievement test scores only 2 to 4% lower in children whose mothers had smoked during pregnancy. The behavioral abnormalities in children of smokers were associated with elevated neonatal hemoglobin levels and low birth weights, suggesting that fetal hypoxemia possibly may contribute to the genesis of behavioral abnormalities.


Assuntos
Desenvolvimento Infantil , Efeitos Tardios da Exposição Pré-Natal , Fumar , Atenção , Criança , Comportamento Infantil , Feminino , Hemoglobinas/análise , Humanos , Recém-Nascido , Aprendizagem , Masculino , Atividade Motora , Gravidez , Estudos Prospectivos
20.
Pediatrics ; 69(6): 724-7, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7079037

RESUMO

In order to determine whether pregnancy outcome was altered when women were employed outside their homes, 7,722 pregnancies were analyzed. Gestations were not shortened but newborns of women who worked in the third trimester weighed 150 to 400 gm less than newborns of mothers who remained at home. The growth retardation was greatest when women were underweight pregravid and had a low pregnancy weight gain, when they were hypertensive, or when the work required standing. The growth retardation remained after the data were stratified by race, socioeconomic status, and other maternal factors that commonly influence fetal growth. The frequency of large placental infarcts progressively increased when women continued stand-up work into late gestation. Such infarcts reached a peak of 250/1,000 births after the 37th week of gestation in stand-up workers. Low uteroplacental blood flow is a likely explanation for both the fetal growth retardation and the large placental infarcts.


Assuntos
Feto/fisiologia , Medicina do Trabalho , Gravidez , Peso ao Nascer , Etnicidade , Feminino , Retardo do Crescimento Fetal/etiologia , Humanos , Hipertensão , Postura , Complicações Cardiovasculares na Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Estados Unidos
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