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1.
Infect Prev Pract ; 3(3): 100151, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34647007

RESUMO

BACKGROUND: Periodic point prevalence surveys (PPSs) provide a method for assessing changes in healthcare-associated infections (HAIs) and antimicrobial use over time. Following the introduction of an antimicrobial stewardship programme at Nagoya University Hospital (Aichi, Japan) a five-year PPS study was performed to highlight any epidemiological changes. METHODS: One-day PPSs were performed annually in July at Nagoya University Hospital. Data on patient characteristics, medical devices, active HAIs and antimicrobial use were collected using a standard data-collection form. RESULTS: A total of 4339 patients were included. Over the five-year study period the median patient age was 62 years, median duration of hospital admission was nine days, 9% of patients had an HAI and 35.2% received at least one antimicrobial. Overall there were 406 HAIs (95% confidence interval, 369-447) with surgical site infection, pneumonia and febrile neutropenia occurring most frequently. Enterobacterales were the most common pathogens (N = 78, 28.6%) and 32.1% were third-generation cephalosporin-resistant. Meropenem was the most frequently prescribed antimicrobial for HAIs. Surgical antimicrobial prophylaxis changed drastically, with shorter durations and a marked reduction in oral cephalosporin use. However, antimicrobials for medical prophylaxis gradually increased. CONCLUSIONS: This five-year PPS study shows consistent data for patient background, HAIs and causative pathogens and highlights changes in antimicrobial use during the era of the National Action Plan on Antimicrobial Resistance. To describe the epidemiology of Japanese hospitals by PPS, multicentre PPSs including in community hospitals should be performed annually.

2.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397250

RESUMO

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

3.
Vet J ; 266: 105571, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33323173

RESUMO

Canine transitional cell carcinoma (cTCC) is the most common malignant tumour in the urinary bladder: it is highly invasive and exhibits metastatic characteristics. Inflammation is also strongly related to cTCC. Epithelial tumours often exhibit a mesenchymal cell phenotype during tumour invasion and metastasis owing to epithelial-mesenchymal transition (EMT), which is often induced in chronic inflammation. The aim of this retrospective study was to investigate the expression of epithelial and mesenchymal cell markers in tumour cells and to evaluate its relationship with prognosis of cTCC. In this study, 29 dogs with cTCC who underwent surgical treatment were enrolled. Clinical parameters were reviewed using medical records. Tissue expression of epithelial and mesenchymal markers was evaluated by immunohistochemical analysis. The association between the expression of mesenchymal cell markers and clinical parameters, including prognosis, was statistically examined. In five normal bladder tissues used as controls, no expression of mesenchymal markers was observed, except for one tissue that expressed fibronectin. Conversely, epithelial tumour cells expressed vimentin and fibronectin in 23/29 and 19/28 cTCC tissues, respectively. Regarding clinical parameters, vimentin score in Miniature Dachshunds was significantly higher than those in other dog breeds (P < 0.001). Multivariate survival analyses revealed that age>12 years was related to shorter progression-free survival (P = 0.02). Higher vimentin score, lower fibronectin score, and advanced clinical T stage were significantly correlated with shorter median survival time (P < 0.05). The results of this study indicate that vimentin expression was associated with cTCC progression. Further studies are needed to examine the incidence and relevance of EMT in cTCC.


Assuntos
Carcinoma de Células de Transição/veterinária , Doenças do Cão/patologia , Transição Epitelial-Mesenquimal , Neoplasias da Bexiga Urinária/veterinária , Fatores Etários , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Doenças do Cão/metabolismo , Cães , Feminino , Fibronectinas/metabolismo , Imuno-Histoquímica , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/metabolismo , Vimentina/metabolismo
4.
Sci Adv ; 6(49)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33268373

RESUMO

The color of firefly bioluminescence is determined by the structure of luciferase. Firefly luciferase genes have been isolated from more than 30 species, producing light ranging in color from green to orange-yellow. Here, we reconstructed seven ancestral firefly luciferase genes, characterized the enzymatic properties of the recombinant proteins, and determined the crystal structures of the gene from ancestral Lampyridae. Results showed that the synthetic luciferase for the last common firefly ancestor exhibited green light caused by a spatial constraint on the luciferin molecule in enzyme, while fatty acyl-CoA synthetic activity, an original function of firefly luciferase, was diminished in exchange. All known firefly species are bioluminescent in the larvae, with a common ancestor arising approximately 100 million years ago. Combined, our findings propose that, within the mid-Cretaceous forest, the common ancestor of fireflies evolved green light luciferase via trade-off of the original function, which was likely aposematic warning display against nocturnal predation.

5.
J Chem Phys ; 148(8): 084307, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495759

RESUMO

The triple differential cross sections (TDCSs) have been obtained for the electron impact ionization of ionic targets, Al3+(2p) and Be2+(1s), having nearly the same ratio of ionic charge to radius. In the first of this kind of study, the trends of cross sections have been found to match to a greater extent despite ionization taking place from the ionic targets having considerable difference in nuclear charges as well as the ionization taking place from different types of orbitals, p-orbital and s-orbital. The trends of TDCSs have not been found to agree considerably for the neutral Al (3p) and Be (2s) targets.

6.
Acta Neurol Scand ; 137(4): 432-437, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29313881

RESUMO

BACKGROUND: Cross-sensitivity of rash has been reported between various antiepileptic drugs (AEDs). However, few studies have determined the frequency and management of cross-sensitivity in patients with super-refractory status epilepticus (SRSE). AIMS OF THE STUDY: To examine the optimal AED for treating SRSE with cross-sensitivity. METHODS: We performed a retrospective review of adult patients with SRSE treated at Nagoya City University Hospital, in which we investigated the frequency of cross-sensitivity among patients with SRSE and their clinical and medical profiles. RESULTS: We identified 10 adult patients with SRSE, 5 of whom had cross-sensitivity. Stiripentol (STP) was administered when previously used AEDs had demonstrated cross-sensitivity and failed to control seizures. After initiation of STP, the dose of general anaesthetics was reduced, and status epilepticus (SE) eventually ceased with co-administered AEDs without additional adverse effects. The mean time to SE cessation after initiation of STP was 30.8 days (range, 18-46 days), mean duration of general anaesthesia was 101.2 days (range, 74-128 days), and mean number of AEDs was 9.0 (range, 6-11). CONCLUSIONS: This study suggests that cross-sensitivity between AEDs is common in adults with SRSE and that STP may be useful for treating SRSE with cross-sensitivity.


Assuntos
Anticonvulsivantes/efeitos adversos , Dioxolanos/uso terapêutico , Toxidermias/etiologia , Estado Epiléptico/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Convulsões/tratamento farmacológico , Adulto Jovem
7.
Photochem Photobiol Sci ; 15(5): 654-65, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27101527

RESUMO

Beetle luciferases, the enzymes responsible for bioluminescence, are special cases of CoA-ligases which have acquired a novel oxygenase activity, offering elegant models to investigate the structural origin of novel catalytic functions in enzymes. What the original function of their ancestors was, and how the new oxygenase function emerged leading to bioluminescence remains unclear. To address these questions, we solved the crystal structure of a recently cloned Malpighian luciferase-like enzyme of unknown function from Zophobas morio mealworms, which displays weak luminescence with ATP and the xenobiotic firefly d-luciferin. The three dimensional structure of the N-terminal domain showed the expected general fold of CoA-ligases, with a unique carboxylic substrate binding pocket, permitting the binding and CoA-thioesterification activity with a broad range of carboxylic substrates, including short-, medium-chain and aromatic acids, indicating a generalist function consistent with a xenobiotic-ligase. The thioesterification activity with l-luciferin, but not with the d-enantiomer, confirms that the oxygenase activity emerged from a stereoselective impediment of the thioesterification reaction with the latter, favoring the alternative chemiluminescence oxidative reaction. The structure and site-directed mutagenesis support the involvement of the main-chain amide carbonyl of the invariant glycine G323 as the catalytic base for luciferin C4 proton abstraction during the oxygenase activity in this enzyme and in beetle luciferases (G343).


Assuntos
Besouros/química , Proteínas de Insetos/química , Luciferases/química , Oxigenases/química , Sequência de Aminoácidos , Animais , Coenzima A Ligases/química , Coenzima A Ligases/metabolismo , Besouros/enzimologia , Besouros/metabolismo , Cristalografia por Raios X , Esterificação , Proteínas de Insetos/metabolismo , Luciferases/metabolismo , Modelos Moleculares , Oxigenases/metabolismo , Conformação Proteica , Domínios Proteicos
8.
J Chem Phys ; 143(17): 174701, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26547176

RESUMO

The structural parameters of ultra-thin zinc oxide films on Rh(100) are investigated using low-energy electron diffraction intensity (LEED I-V) curves, scanning tunneling microscopy (STM), and first-principles density functional theory (DFT) calculations. From the analysis of LEED I-V curves and DFT calculations, two optimized models A and B are determined. Their structures are basically similar to the planer h-BN ZnO(0001) structure, although some oxygen atoms protrude from the surface, associated with an in-plane shift of Zn atoms. From a comparison of experimental STM images and simulated STM images, majority and minority structures observed in the STM images represent the two optimized models A and B, respectively.

9.
J Neuroendocrinol ; 27(5): 335-42, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25702774

RESUMO

Although it has been reported that oxytocin stimulates lipolysis in adipocytes, changes in the expression of oxytocin receptor (OTR) mRNA in adipogenesis are still unknown. The present study aimed to investigate the expression of OTR mRNA during adipocyte differentiation and fat accumulation in adipocytes. OTR mRNA was highly expressed in adipocytes prepared from mouse adipose tissues compared to stromal-vascular cells. OTR mRNA expression was increased during the adipocyte differentiation of 3T3-L1 cells. OTR expression levels were higher in subcutaneous and epididymal adipose tissues of 14-week-old male mice compared to 7-week-old male mice. Levels of OTR mRNA expression were higher in adipose tissues at four different sites of mice fed a high-fat diet than in those of mice fed a normal diet. The OTR expression level was also increased by refeeding for 4 h after fasting for 16 h. Oxytocin significantly induced lipolysis in 3T3-L1 adipocytes. In conclusion, a new regulatory mechanism is demonstrated for oxytocin to control the differentiation and fat accumulation in adipocytes via activation of OTR as a part of the hypothalamic-pituitary-adipose axis.


Assuntos
Adipogenia/genética , Regulação da Expressão Gênica , Receptores de Ocitocina/genética , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Envelhecimento/genética , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Dieta Hiperlipídica , Regulação da Expressão Gênica/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Masculino , Camundongos , Ocitocina/farmacologia
10.
Biochemistry ; 52(23): 3963-73, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23705763

RESUMO

The origin of luciferases and of bioluminescence is enigmatic. In beetles, luciferases seem to have evolved from AMP-CoA-ligases. How the new oxygenase luminogenic function originated from AMP-ligases leading to luciferases is one of the most challenging mysteries of bioluminescence. Comparison of the cloned luciferase-like enzyme from the nonluminescent Zophobas morio mealworm and beetle luciferases showed that the oxygenase activity may have emerged as a stereoselective oxidative drift with d-luciferin, a substrate that cannot be easily thioesterified to CoA as in the case of the l-isomer. While the overall kcat displayed by beetle luciferases is orders of magnitude greater than that of the luciferase-like enzyme, the respective oxidation rates and quantum yields of bioluminescence are roughly similar, suggesting that the rate constant of the AMP-ligase activity exerted on the new d-luciferin substrate in beetle protoluciferases was the main enzymatic property that suffered optimization during the evolution of luciferases. The luciferase-like enzyme and luciferases boost the rate of luciferyl-adenylate chemiluminescent oxidation by factors of 10(6) and 10(7), respectively, as compared to the substrate spontaneous oxidation in buffer. A similar enhancement of luciferyl-adenylate chemiluminescence is provided by nucleophilic aprotic solvents, implying that the peptide bonds in the luciferin binding site of beetle luciferase could provide a similar catalytically favorable environment. These data suggest that the luciferase-like enzyme and other similar AMP-ligases are potential alternative oxygenases. Site-directed mutagenesis studies of the luciferase-like enzyme and the red light-producing luciferase of Phrixotrix hirtus railroadworm confirm here a critical role for T/S345 in luciferase function. Mutations such as I327T/S in the luciferase-like enzyme, which simultaneously increases luciferase activity and promotes blue shifts in the emission spectrum, could have been critical for evolving functional bioluminescence from red-emitting protoluciferases. Through the combination of I327T/S mutations and N-terminal fusion, the luminescence activity of this enzyme was increased to visible levels, with the development of a totally new orange-emitting luciferase. These results open the possibility of engineering luciferase activity in a set of AMP-CoA-ligases.


Assuntos
Coenzima A Ligases/química , Proteínas de Insetos/química , Luciferases/química , Acil Coenzima A/biossíntese , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Domínio Catalítico , Coenzima A Ligases/genética , Evolução Molecular , Luciferina de Vaga-Lumes/química , Corantes Fluorescentes/química , Proteínas de Insetos/genética , Cinética , Luciferases/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Naftalenossulfonatos/química , Ligação Proteica , Tenebrio/enzimologia
11.
Asian-Australas J Anim Sci ; 25(9): 1316-21, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25049696

RESUMO

Adipokines, adipocyte-derived protein, have important roles in various kinds of physiology including energy homeostasis. Chemerin, one of adipocyte-derived adipokines, is highly expressed in differentiated adipocytes and is known to induce macrophage chemotaxis and glucose intolerance. The objective of the present study was to investigate the changes of chemerin and the chemokine-like-receptor 1 (CMKLR1) gene expression levels during differentiation of the bovine adipocyte and in differentiated adipocytes treated with tumor necrosis factor-α (TNF-α), adiponectin, leptin, and chemerin (peptide analog). The expression levels of the chemerin gene increased at d 6 and 12 of the differentiation period accompanied by increased cytoplasm lipid droplets. From d 6 onward, peroxisome proliferator-activated receptor-γ2 (PPAR-γ2) gene expression levels were significantly higher than that of d 0 and 3. In contrast, CMKLR1 expression levels decreased at the end of the differentiation period. In fully differentiated adipocytes (i.e. at d 12), the treatment of TNF-α and adiponectin upregulated both chemerin and CMKLR1 gene expression levels, although leptin did not show such effects. Moreover, chemerin analog treatment was shown to upregulate chemerin gene expression levels regardless of doses. These results suggest that the expression of chemerin in bovine adipocyte might be regulated by chemerin itself and other adipokines, which indicates its possible role in modulating the adipokine secretions in adipose tissues.

13.
Transpl Infect Dis ; 9(1): 11-5, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17313465

RESUMO

Although foscarnet is a promising alternative for the treatment of cytomegalovirus (CMV) infection, its toxicity can be significant in patients with advanced age. We retrospectively reviewed medical records of 123 patients (median age of 55; range, 17-79) who received reduced-intensity cord blood transplantation (RI-CBT). Patients preemptively received reduced-dose foscarnet 30 mg/kg twice daily when CMV antigenemia exceeded 10/50,000. Sixty-three patients developed CMV antigenemia on a median of day 34, and 29 received foscarnet preemptively. The median level of CMV antigenemia at the initiation of foscarnet was 30. Median duration of foscarnet administration was 24 days. Adverse effects included electrolyte abnormalities (n=19), renal impairment (n=13), and skin eruption requiring discontinuation of foscarnet (n=1). Preemptive therapy of foscarnet was completed in 18 patients. Seven patients died during foscarnet use without developing CMV disease. The remaining 3 developed CMV enterocolitis 5, 14, and 17 days after initiation of foscarnet. All of them were successfully treated with ganciclovir or foscarnet. Reduced dose of foscarnet is beneficial to control CMV reactivation following RI-CBT; however, it has considerable toxicities in RI-CBT recipients with advanced age. Further studies are warranted to minimize toxicities and identify optimal dosages.


Assuntos
Antivirais/administração & dosagem , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus , Foscarnet/administração & dosagem , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Antígenos Virais/sangue , Citomegalovirus/imunologia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/sangue , Enterocolite/tratamento farmacológico , Enterocolite/etiologia , Exantema/induzido quimicamente , Feminino , Ganciclovir/uso terapêutico , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Insuficiência Renal/induzido quimicamente , Estudos Retrospectivos , Resultado do Tratamento , Desequilíbrio Hidroeletrolítico/induzido quimicamente
14.
Cell Death Differ ; 14(4): 727-32, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17170749

RESUMO

Activity-Based Probes (ABPs) are small molecules that form stable covalent bonds with active enzymes thereby allowing detection and quantification of their activities in complex proteomes. A number of ABPs that target proteolytic enzymes have been designed based on well-characterized mechanism-based inhibitors. We describe here the evaluation of a novel series of ABPs based on the aza-aspartate inhibitory scaffold. Previous in vitro kinetic studies showed that this scaffold has a high degree of selectivity for the caspases, clan CD cysteine proteases activated during apoptotic cell death. Aza-aspartate ABPs containing either an epoxide or Michael acceptor reactive group were potent labels of executioner caspases in apoptotic cell extracts. However they were also effective labels of the clan CD protease legumain and showed unexpected crossreactivity with the clan CA protease cathepsin B. Interestingly, related aza peptides containing an acyloxymethyl ketone reactive group were relatively weak but highly selective labels of caspases. Thus azapeptide electrophiles are valuable new ABPs for both detection of a broad range of cysteine protease activities and for selective targeting of caspases. This study also highlights the importance of confirming the specificity of covalent protease inhibitors in crude proteomes using reagents such as the ABPs described here.


Assuntos
Compostos Aza/química , Compostos Aza/síntese química , Caspases/química , Cisteína Endopeptidases/química , Sondas Moleculares/química , Caspases/metabolismo , Células Cultivadas , Cisteína Endopeptidases/metabolismo , Eletroquímica , Ativação Enzimática , Humanos , Indicadores e Reagentes , Técnicas de Sonda Molecular , Sondas Moleculares/síntese química , Estrutura Molecular , Especificidade por Substrato
17.
Mol Psychiatry ; 9(3): 293-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15094790

RESUMO

A genetic predisposition to the development of neuroleptic malignant syndrome (NMS) has been suggested by clinical studies. Although the molecular basis of NMS is unclear, a dopaminergic blockade mechanism has been considered the main cause. We therefore investigated the association between NMS and three functional polymorphisms of the dopamine D(2) receptor (DRD(2)) gene: TaqI A, -141C Ins/Del, and Ser311Cys. Subjects included 32 Japanese patients, previously diagnosed with NMS, and 132 schizophrenic patients treated with neuroleptics without occurrence of NMS. Polymerase chain reaction and restriction fragment length polymorphism analyses were performed to determine each genotype. We found significant differences in genotypic and allelic frequencies of the -141C Ins/Del polymorphism between patients with and without NMS. The -141C Del allele was significantly more frequent in the NMS group (23.4 vs 11.7%, P=0.026). Similarly, the proportion of -141C Del allele carriers was significantly higher in the NMS group (40.6 vs 20.5%, P=0.022). No significant differences between the two groups were seen for allelic and genotypic frequencies of the TaqI A and Ser311Cys polymorphisms. This result suggests that the -141C Ins/Del polymorphism is likely to predispose toward the development of NMS, probably together with other unidentified factors.


Assuntos
Síndrome Maligna Neuroléptica/genética , Polimorfismo Genético/genética , Receptores de Dopamina D2/genética , Substituição de Aminoácidos , Povo Asiático/genética , Intervalos de Confiança , DNA/sangue , DNA/isolamento & purificação , Feminino , Frequência do Gene , Triagem de Portadores Genéticos , Genótipo , Humanos , Japão , Leucócitos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Deleção de Sequência
18.
FEMS Microbiol Lett ; 195(2): 217-22, 2001 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-11179655

RESUMO

The adhesion properties of the recombinant fimbriae (r-fimbriae) recovered from a YH522 transformant of Porphyromonas gingivalis which harbors a chimeric plasmid, pYHF2, containing the fimA gene of strain 381 were compared with those of the endogenous fimA fimbriae of strain 33277. The adhesion level of the r-fimbriae to Actinomyces viscosus was clearly lower than that of the endogenous fimbriae. In addition, the r-fimbriae were shown to lack some minor components detectable in the endogenous fimbriae. The plasmid pYHF2 prepared from the YH522 transformant was then transformed into six different P. gingivalis strains and the resultant pYHF2-containing strains were examined for their fimbrial expression. In spite of the presence of a considerable diversity in the expression level of the r-fimbriae among these transformants, it was evident that the strains expressing higher levels of the r-fimbriae exhibited a greater decrease in adhesion activity to other bacteria and to oral epithelial cells, as well as in self-aggregation.


Assuntos
Aderência Bacteriana , Proteínas de Bactérias/fisiologia , Proteínas de Fímbrias , Fímbrias Bacterianas/fisiologia , Gengiva/microbiologia , Porphyromonas gingivalis/fisiologia , Actinomyces viscosus/fisiologia , Proteínas de Bactérias/genética , Células Cultivadas , Células Epiteliais/microbiologia , Fímbrias Bacterianas/genética , Gengiva/citologia , Hemaglutinação , Humanos , Plasmídeos , Porphyromonas gingivalis/genética , Transformação Bacteriana , Células Tumorais Cultivadas
19.
J Physiol Anthropol Appl Human Sci ; 19(2): 61-71, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10870241

RESUMO

With the goal of achieving an intelligent robot camera system that can take dynamic images automatically through humanlike, natural camera work, we analyzed how images were shot, subjectively evaluated reproduced images, and examined effects of camerawork, using camera control technique as a parameter. It was found that (1) A high evaluation is obtained when human-based data are used for the position adjusting velocity curve of the target; (2) Evaluation scores are relatively high for images taken with feedback-feedforward camera control method for target movement in one direction; (3) Keeping the target within the image area using the control method that imitates human camera handling becomes increasingly difficult when the target changes both direction and velocity and becomes bigger and faster, and (4) The mechanical feedback method can cope with rapid changes in the target's direction and velocity, constantly keeping the target within the image area, though the viewer finds the image rather mechanical as opposed to humanlike.


Assuntos
Meios de Comunicação de Massa , Robótica/métodos , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Gravação em Vídeo/instrumentação
20.
Br J Cancer ; 80(7): 946-53, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10362101

RESUMO

Benzoporphyrin derivative monoacid (BPD-MA) photosensitization was examined for its effects on cellular adhesion of a human ovarian cancer cell line, OVCAR 3, to extracellular matrix (ECM) components. Mild BPD-MA photosensitization (approximately 85% cell survival) of OVCAR 3 transiently decreased adhesion to collagen IV, fibronectin, laminin and vitronectin to a greater extent than could be attributed to cell death. The loss in adhesiveness was accompanied by a loss of beta1 integrin-containing focal adhesion plaques (FAPs), although beta1 subunits were still recognized by monoclonal antibody directed against human beta1 subunits. In vivo BPD-MA photosensitization decreased OVCAR 3 adhesiveness as well. Photosensitized adhesion was reduced in the presence of sodium azide and enhanced in deuterium oxide, suggesting mediation by singlet oxygen. Co-localization studies of BPD-MA and Rhodamine 123 showed that the photosensitizer was largely mitochondrial, but also exhibited extramitochondrial, intracellullar, diffuse cytosolic fluorescence. Taken together, these data show that intracellular damage mediated by BPD-PDT remote from the FAP site can affect cellular-ECM interactions and result in loss of FAP formation. This may have an impact on long-term effects of photodynamic therapy. The topic merits further investigation.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Integrina beta1/biossíntese , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Animais , Catalase/farmacologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/efeitos da radiação , Óxido de Deutério/farmacologia , Feminino , Humanos , Integrina beta1/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/radioterapia , Porfirinas/metabolismo , Azida Sódica/farmacologia , Superóxido Dismutase/farmacologia
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