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1.
Klin Monbl Augenheilkd ; 233(4): 434-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27116502

RESUMO

Background. Microemboli of fat or other material into the terminal macular retinal circulation can be difficult to diagnose. We report 2 cases that showed subtle signs where SLO fundus imaging was most sensitive to precisely outline the limits of the inner retina infarction. Patients and Methods. Multimodal imaging analysis was performed including fundus photography, fluorescein angiography, indocyanine green angiography, Optical Coherence Tomography and SLO fundus imaging of 2 cases with suspected infarction of the inner retina. Cases. A 30-year-old man reported a grey central spot OD a few days after being squeezed between two cars with a sacrum fracture. Vision was 0.2 OD, and 1.0 OS. Examination was unremarkable and fluorescein angiography was normal. Octopus visual field showed a tiny central scotoma OD. Microperimetry showed decreased central sensitivity OD > OS. The only sign was a dark area on the SLO fundus picture indicating a subtle infarction of the inner retina (OD > OS) with nothing visible on the OCT. Resolution of lesions on the SLO picture ODS occurred in parallel with improvement of microperimetry and visual acuity. A 32-year-old woman suspected to take IV drugs had a sudden drop of vision to 0.4 OD and count fingers at 6 feet OS. Signs included macular hemorrhages and non perfusion on FA. The striking sign was a large dark area on the SLO picture precisely delineating the more extensive infarcted area of internal retina corresponding to OCT hyperreflectivity, visible in this case. Conclusions. Macular ischemia due to microemboli can show obvious fundus signs as hemorrhages, cotton wool spots and non perfusion or can present in a subclinical fashion. The SLO picture has a higher image contrast and higher resolution compared to conventional fundus photography and so can precisely delineate ischemic changes of the inner retina causing the unexplained visual loss.


Assuntos
Embolia/diagnóstico por imagem , Microscopia Confocal/métodos , Imagem Multimodal/métodos , Oftalmoscopia/métodos , Perfurações Retinianas/diagnóstico por imagem , Adulto , Embolia/patologia , Feminino , Fundo de Olho , Humanos , Masculino , Reprodutibilidade dos Testes , Perfurações Retinianas/patologia , Sensibilidade e Especificidade
3.
J Phys Condens Matter ; 20(46): 465105, 2008 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21693839

RESUMO

Fe and Y K-edge extended x-ray absorption fine structure, Fe(Y) L(3,2)-edge (L(3)-edge) x-ray absorption near-edge structure (XANES) and valence-band photoemission spectroscopy (VB-PES) measurements have been carried out to study soft magnetic ternary Fe(78-x)Y(x)B(22) bulk metallic glasses (BMGs). The combined XANES and VB-PES results do not show broadening of the Fe 3d band to support the previous interpretation of the reduction of the magnetic moment in BMGs by Y-induced decrease of exchange splitting of Fe 3d orbitals. Instead, the density of delocalized/itinerant Fe 3d states in the vicinity of the Fermi level is found to be reduced by Y substitution, which reduces the strength of itinerant-states-mediated ferromagnetic coupling between local spins on the Fe ions and the total magnetic moment of the Fe-based BMGs.

4.
Cell Death Differ ; 7(8): 706-11, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10918444

RESUMO

The tumor suppressor gene p16INK4A is a cyclin-dependent kinase inhibitor (CDKI) and an important cell cycle regulator. We have previously constructed a recombinant adenovirus which expresses p16 (Adp16) and shown that infection in a variety of human tumor cell lines with this recombinant virus results in high levels of p16INK4A protein expression resulting in cell cycle arrest and loss of cyclin-cdk activity. Furthermore, adenoviral-mediated overexpression of wild-type p16INK4A is more toxic in cancer cells which express mutant forms of p16INK4A compared to cancer cell lines containing endogenous wild-type p16. TUNEL assay and DAPI staining following infection of MDA-MB 231 breast cancer cells with Adp16 indicate that p16INK4A-mediated cytotoxicity was associated with apoptosis. This is supported by studies demonstrating a decrease in cpp32 and cyclinB1 protein levels and induction of poly (ADP-ribose) polymerase (PARP) cleavage following infection of MDA-MB-231 cells with Adp16. These results suggest that gene therapy using Adp16 may be a promising treatment option for human cancers containing alterations in p16 expression.


Assuntos
Apoptose , Proteínas de Transporte/biossíntese , Adenoviridae , Proteínas de Transporte/genética , Caspase 3 , Caspases/metabolismo , Linhagem Celular , Inibidor p16 de Quinase Dependente de Ciclina , Expressão Gênica , Vetores Genéticos , Humanos , Mutagênese , Poli(ADP-Ribose) Polimerases/metabolismo , Células Tumorais Cultivadas
5.
Eur J Clin Nutr ; 69(8): 969-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25804268

RESUMO

The goal of this open-label trial was to examine the efficacy and safety of a 12-week omega-3 fatty acids supplementation among children suffering with Autism Spectrum Disorders (ASD). A total of 41 children and adolescents aged 7-18 years (36 boys, 5 girls; mean age = 11.66, s.d. = 3.05) diagnosed with ASD participated in the study. At post-treatment, participants showed significant improvements on all subscales of the Social Responsiveness Scale (P < 0.01) and the Social and Attention Problems syndrome scales of the Child Behavior Checklist (P < 0.05). Blood fatty acid levels were significantly correlated with changes in the core symptoms of ASD. Baseline levels of blood fatty acid levels were also predictive of response to the omega-3 treatment. Omega-3 fatty acids supplementation was well-tolerated and did not cause any serious side effects. Our findings lend some preliminary support for the use of omega-3 fatty acids supplementation in addressing ASD. Future randomized controlled trials of omega-3 fatty acids in ASD with blood fatty acid measurements with a larger sample and longer follow-up period is warranted.


Assuntos
Transtorno do Espectro Autista/tratamento farmacológico , Suplementos Nutricionais , Ácidos Graxos Ômega-3/uso terapêutico , Adolescente , Atenção , Transtorno do Espectro Autista/sangue , Transtorno do Espectro Autista/psicologia , Escala de Avaliação Comportamental , Criança , Ácidos Graxos/sangue , Feminino , Humanos , Masculino , Projetos Piloto , Singapura , Resultado do Tratamento
6.
Sci Rep ; 5: 11466, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-26098075

RESUMO

The correlation between sub-band gap absorption and the chemical states and electronic and atomic structures of S-hyperdoped Si have been extensively studied, using synchrotron-based x-ray photoelectron spectroscopy (XPS), x-ray absorption near-edge spectroscopy (XANES), extended x-ray absorption fine structure (EXAFS), valence-band photoemission spectroscopy (VB-PES) and first-principles calculation. S 2p XPS spectra reveal that the S-hyperdoped Si with the greatest (~87%) sub-band gap absorption contains the highest concentration of S(2-) (monosulfide) species. Annealing S-hyperdoped Si reduces the sub-band gap absorptance and the concentration of S(2-) species, but significantly increases the concentration of larger S clusters [polysulfides (Sn(2-), n > 2)]. The Si K-edge XANES spectra show that S hyperdoping in Si increases (decreased) the occupied (unoccupied) electronic density of states at/above the conduction-band-minimum. VB-PES spectra evidently reveal that the S-dopants not only form an impurity band deep within the band gap, giving rise to the sub-band gap absorption, but also cause the insulator-to-metal transition in S-hyperdoped Si samples. Based on the experimental results and the calculations by density functional theory, the chemical state of the S species and the formation of the S-dopant states in the band gap of Si are critical in determining the sub-band gap absorptance of hyperdoped Si samples.

7.
J Immunol Methods ; 58(1-2): 25-9, 1983 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-6833767

RESUMO

Precise quantitative heat transfer information in microtitration plates can be obtained by filling the wells of a microtitration plate with cholesteric liquid crystals and incubating the plates at the desired temperature in different incubators. The liquid crystals indicate temperature by changes in discrete reproducible colors over various temperature ranges. With these instrumented plates, interwell thermal gradients may be documented visually and are in close agreement with results obtained by using wire thermocouple measuring techniques.


Assuntos
Colesterol , Microquímica/instrumentação , Temperatura , Cristalização , Incubadoras
8.
Mol Cells ; 12(3): 304-12, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11804328

RESUMO

4-1BB, a member of the tumor necrosis factor receptor (TNFR) superfamily, is induced on CD4+ and CD8+ T cells upon engagement of the T cell receptor (TCR)/ CD3 complex with the antigen bound to MHC. 4-1BB plays an important role in transmitting costimulatory signal during T cell activation. However, 4-1BB-mediatded signal transduction pathways have remained elusive. We conducted the yeast two-hybrid screening to identify intracellular signaling molecules that associate with 4-1BB. A novel leucine-rich repeat (LRR)-containing protein, herein named LRR-1, was found to specifically interact with the cytoplasmic domain of 4-1BB. Overexpression of LRR-1 suppressed the activation of NF-KB induced by 4-1BB or TNF receptor-associated factor (TRAF) 2. In addition, LRR-1 down-regulated JNK1 activity was induced by 4-1BB. These results indicate that LRR-1 negatively regulates the 4-1BB-mediated signaling cascades which result in the activation of NF-kappaB and JNK1.


Assuntos
Proteínas/genética , Receptores de Fator de Crescimento Neural/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais/fisiologia , Sequência de Aminoácidos , Antígenos CD , Clonagem Molecular , Regulação para Baixo , Humanos , Proteína Quinase 8 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , NF-kappa B/metabolismo , Estrutura Terciária de Proteína , Proteínas/metabolismo , Sequências Repetitivas de Aminoácidos/genética , Proteínas Repressoras , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Técnicas do Sistema de Duplo-Híbrido
9.
Am J Vet Res ; 50(8): 1352-60, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2675696

RESUMO

An ELISA has been developed for measurement of milk and serum IgG concentrations directed against Salmonella dublin. Four groups of cows were studied: group A--7 experimentally challenge-exposed cows (infected, recovered group); group B--6 normal uninfected randomly selected control cows; group C--7 naturally occurring S dublin carrier cows; and group D--6 normal uninfected S dublin negative cows from the same herd as group C. Group-A cows were inoculated orally, or inoculated orally and then IV, but none became a S dublin carrier. As expected, all 7 group-A cows responded with a marked increase in ELISA titer after oral exposure to virulent S dublin, starting with a mean serum titer of 17.7% and reaching a peak mean serum titer of 79.3% approximately 76 days after initial exposure. As determined by necropsy and organ culturing of the remaining cows, none of the group-A cows became carriers. The mean serum ELISA titer for group-B uninfected control cows was 14.1% (SD +/- 12.8%). The mean milk ELISA titer was -1.0% (SD +/- 5.5%). Colostrum and then milk gave false-positive results for up to 2 weeks after onset of lactation. Group-B cows were culture negative for S dublin in feces and milk during lactation, and when tissues were cultured after euthanasia. Milk and serum samples for ELISA, and milk and fecal samples for culturing were taken from all group-A and -B cows twice a week for 6 months. Statistical correlation (P less than 0.05) was found between serum and milk ELISA titers.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Antibacterianos/análise , Portador Sadio/veterinária , Doenças dos Bovinos/diagnóstico , Leite/imunologia , Salmonelose Animal/diagnóstico , Salmonella/imunologia , Animais , Técnicas Bacteriológicas/veterinária , Portador Sadio/diagnóstico , Portador Sadio/microbiologia , Bovinos , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/microbiologia , Feminino , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/diagnóstico , Salmonella/isolamento & purificação , Salmonelose Animal/microbiologia
10.
Environ Sci Technol ; 43(9): 3128-34, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19534124

RESUMO

Iron-monosulfide oxidation and associated S transformations in a natural sediment were examined by combining selective extractions, electron microscopy and S K-edge X-ray absorption near-edge structure (XANES) spectroscopy, The sediment examined in this study was collected from a waterway receiving acid-sulfate soil drainage. It contained a high acid-volatile sulfide content (1031 micromol g(-1)), reflecting an abundance of iron-monosulfide. The iron-monosulfide speciation in the initial sediment sample was dominated by nanocrystalline mackinawite (tetragonal FeS). At near-neutral pH and an 02 partial pressure of approximately 0.2 atm, the mackinawite was found to oxidize rapidly, with a half-time of 29 +/- 2 min. This oxidation rate did not differ significantly (P < 0.05) between abiotic versus biotic conditions, demonstrating that oxidation of nanocrystalline mackinawite was not microbially mediated. The extraction results suggested that elemental S (S8(0)) was a key intermediate S oxidation product Transmission electron microscopy showed the S8(0) to be amorphous nanoglobules, 100-200 nm in diameter. The quantitative importance of S8(0) was confirmed by linear combination XANES spectroscopy, after accounting for the inherent effect of the nanoscale S8(0) particle-size on the corresponding XANES spectrum. Both the selective extraction and XANES data showed that oxidation of S8(0) to SO4(2-) was mediated by microbial activity. In addition to directly revealing important S transformations, the XANES results support the accuracy of the selective extraction scheme employed here.


Assuntos
Bactérias/metabolismo , Compostos Ferrosos/química , Compostos Ferrosos/isolamento & purificação , Sedimentos Geológicos/química , Microscopia Eletrônica , Enxofre/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Oxirredução , Análise Espectral
11.
Phys Rev Lett ; 96(25): 256402, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16907328

RESUMO

Using x-ray absorption spectroscopy at the Ru-L2,3 edge we reveal that the Ru4+ ions remain in the S=1 spin state across the rare 4d-orbital ordering transition and spin-gap formation. We find using local spin density approximation + Hubbard U band structure calculations that the crystal fields in the low-temperature phase are not strong enough to stabilize the S=0 state. Instead, we identify a distinct orbital ordering with a significant anisotropy of the antiferromagnetic exchange couplings. We conclude that La4Ru2O10 appears to be a novel material in which the orbital physics drives the formation of spin-singlet dimers in a quasi-two-dimensional S=1 system.

12.
Biotechnol Bioeng ; 43(2): 183-5, 1994 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-18615613

RESUMO

The diffusivity of Cu(2+) in calcium alginate beads calculated by the shrinking core model (SCM) was reevaluated in this work. The results obtained in this work were significantly different than those by the original authors. There were excellent agreements between the results obtained by the SCM in this work and those by the more rigorous linear absorption model (LAM) by the original authors.

13.
Biotechnol Bioeng ; 37(3): 266-73, 1991 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-18597364

RESUMO

The recovery of copper from synthetic aqueous media circulating in a loop fluidized bed reactor operated batchwise was investigated by using the following biopolymer systems: (1) a viscous solution of sodium alginate (from kelp) dispensed directly into the reactor fluid containing dissolved copper (sulfate salt) at initial concentrations of 60-200 ppm, (2) partially coagulated calcium alginate spheres for absorbing dissolved copper at initial concentrations of 10-40 ppm, and (3) a mixture of green algae Microcystis and sodium alginate dispensed directly into the reactor fluid. The recovery of copper and cobalt, a strategic metal, from cobalt ore leachate was achieved by a two-step approach: direct dispensing of sodium alginate to absorb the bulk of metals followed by the addition of partially coagulated calcium alginate spheres to "polish" the leachate. Metal binding capacity and conditional stability constant of each biopolymer system as well as the effective diffusivity of cupric ion in the matrix of biopolymer gels are reported.

14.
World J Surg ; 19(5): 729-33, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7571671

RESUMO

To determine management guidelines for symptomatic duodenal diverticulum, we reviewed medical records of 26 patients. Complicated duodenal diverticulum was the only possible cause of symptoms-abdominal pain, fever and chills, melena, vomiting-in 18 patients. Ten patients improved with conservative management, and eight patients underwent diverticulectomy with or without various other procedures. Among the eight patients, one patient who had duodenal fistula died of respiratory complications on the second postoperative day. Symptoms recurred in two patients: One had a distal common bile duct (CBD) stricture and underwent choledochojejunostomy. In the other patient a CBD stone developed 3 years later, and choledocholithotomy and choledochojejunostomy were performed. Eight patients had associated gallstone disease as well as the diverticulum. Five of the eight had a history of operation for gallstone disease; four improved with conservative treatment, and one underwent choledochojejunostomy. Two patients were thought to have an innocent diverticulum and underwent cholecystectomy and choledocholithotomy only. One patient underwent diverticulectomy and sphincteroplasty for a CBD stone and pervaterian diverticulum. In conclusion, operations for duodenal diverticulum should be reserved for seriously complicated diverticula, and the surgeon should be aware that pervaterian diverticulum can be a cause of choledocholithiasis.


Assuntos
Divertículo/cirurgia , Duodenopatias/cirurgia , Idoso , Divertículo/diagnóstico , Duodenopatias/diagnóstico , Feminino , Cálculos Biliares/etiologia , Cálculos Biliares/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Reoperação
15.
Biopolymers ; 28(8): 1485-9, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2752102

RESUMO

The osmotic coefficients phi p,Na of dilute solutions of the sodium form of some weakly acidic polymers are theoretically predicted in this work. Based on the measured value 0.73 of gamma Na, the activity coefficient of free Na+, of the completely ionized humic acid (sodium salt) in a salt-free solution, the effective interligand distance b is calculated to be 11.34 A by using Manning's counterion condensation theory [Manning, G. S. (1969) J. Chem. Phys. 51(3), 924]. The corresponding values of gamma Na (measured experimentally) and b for the completely ionized exopolymer of Pseudomonas atlantica are 0.624 and 7.57 A when cultivated at a dilution rate D = 0.015 h-1, 0.647 and 8.19 A at D = 0.025 h-1, and 0.613 and 7.29 Aat D = 0.06 h-1. For alginic acid (in the completely ionized sodium form), gamma Na = 0.40 and b = 4.71 A. The osmotic coefficients phi p,Na for the partially and the completely ionized polymers are then predicted with Manning's theory as well.


Assuntos
Biopolímeros , Substâncias Macromoleculares , Eletrólitos , Concentração Osmolar , Sódio , Soluções
16.
Appl Environ Microbiol ; 46(5): 1066-72, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16346414

RESUMO

This paper presents a bench-scale study on the transport in highly permeable porous rock of three bacterial species-Bacillus subtilis, Pseudomonas putida, and Clostridium acetobutylicum-potentially applicable in microbial-enhanced oil recovery processes. The transport of cells during the injection of bacterial suspension and nutrient medium was simulated by a deep bed filtration model. Deep bed filtration coefficients and the maximum capacity of cells in porous rock were measured. Low to intermediate ( approximately 10/ml) injection concentrations of cellular suspensions are recommended because plugging of inlet surface is less likely to occur. In addition to their resistance to adverse environments, spores of clostridia are strongly recommended for use in microbial-enhanced oil recovery processes since they are easiest among the species tested to push through porous rock. After injection, further transport of bacteria during incubation can occur by growth and mobility through the stagnant nutrient medium which fills the porous rock. We have developed an apparatus to study the migration of bacteria through a Berea sandstone core containing nutrient medium.

17.
Ann Allergy ; 48(5): 283-7, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-7081781

RESUMO

A previous article has shown a diminished phagocytic and intracellular metabolic activity of the polymorphonuclear cells (PMN's) from patients with rheumatoid arthritis (RA). No correlation was found between PMN's functions with either clinical or laboratory expression of disease activity. In the present study the effects of rheumatoid sera on PMN's functions were investigated and the results revealed significant inhibition of phagocytic activity (PA) and nitroblue tetrazolium (NBT) dye reduction capacity of cells from RA as well as from a normal (N) control group. The number of PMN's showing aggregated latex particles on their surfaces was significantly higher in RA patient groups in the presence of rheumatoid sera. PMN's from N and RA groups were lysed in the presence of rheumatoid sera, with more significant destruction of RA-PMN's. No correlation was found between the PMN's function and the amount of circulating immune complexes (CIC's) or rheumatoid factor (RF). Significantly lower concentration of complement (C4) levels and higher IgA mean values were observed in the patient group compared to the standard values. The mechanism(s) underlying the impaired PA and NBT reduction may be due to defective intrinsic cell function as well as the extra cellular effects of blocking or lytic factors present in rheumatoid sera.


Assuntos
Artrite Reumatoide/imunologia , Neutrófilos/imunologia , Fagócitos/imunologia , Complexo Antígeno-Anticorpo/metabolismo , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Complemento C3/análise , Complemento C4/análise , Humanos , Imunidade Celular , Imunoglobulinas/análise , Neutrófilos/metabolismo , Nitroazul de Tetrazólio , Fagócitos/metabolismo , Fator Reumatoide/farmacologia
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