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1.
Anaesthesia ; 74(12): 1542-1550, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31531850

RESUMO

Patients with obstructive sleep apnoea are at increased risk of adverse postoperative outcomes, such as cardiac and respiratory complications. It has been hypothesised that obstructive sleep apnoea also increases the risk for postoperative delirium and acute postoperative pain. We conducted a retrospective, observational study investigating the relationship of obstructive sleep apnoea with postoperative delirium and acute postoperative pain severity. Patients were classified as being at high risk for obstructive sleep apnoea if they had been diagnosed with this condition, or if they were positive for more than four factors using the 'STOP-BANG' screening tool. Adjusted logistic regression was used to investigate the association between obstructive sleep apnoea and postoperative delirium, and multivariable linear regression to study the relationship between obstructive sleep apnoea and postoperative pain severity. The incidence of postoperative delirium was 307 in 1441 patients (21.3%; 95%CI 19.2-23.5%). In unadjusted analysis, high risk for obstructive sleep apnoea was associated with delirium, with an odds ratio (95%CI) of 1.77 (1.22-2.57; p = 0.003). After adjustment for pre-specified variables, the association was not statistically significant with odds ratio 1.34 (0.80-2.23; p = 0.27). The mean (SD) maximum pain (resting or provoked) reported for the entire cohort was 63.8 (27.9) mm on a 0-100 mm visual analogue scale. High risk for obstructive sleep apnoea was not associated with postoperative pain severity (ß-coefficient 2.82; 95%CI, -2.34-7.97; p = 0.28). These findings suggest that obstructive sleep apnoea is unlikely to be a strong risk factor for postoperative delirium or acute postoperative pain severity.


Assuntos
Delírio do Despertar/complicações , Dor Pós-Operatória/complicações , Apneia Obstrutiva do Sono/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Delírio do Despertar/epidemiologia , Feminino , Humanos , Incidência , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Apneia Obstrutiva do Sono/epidemiologia , Inquéritos e Questionários , Adulto Jovem
2.
ACS Nano ; 8(6): 6242-9, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24841152

RESUMO

Self-assembled nanocomposites with a high interface-to-volume ratio offer an opportunity to overcome limitations in current technology, where intriguing transport behaviors can be tailored by the choice of proper interactions of constituents. Here we integrated metallic perovskite oxide SrRuO3-wurzite semiconductor ZnO nanocomposites to investigate the room-temperature metal-insulator transition and its effect on photoresponse. We demonstrate that the band structure at the interface can be tuned by controlling the interface-to-volume ratio of the nanocomposites. Photoinduced carrier injection driven by visible light was detected across the nanocomposites. This work shows the charge interaction of the vertically integrated multiheterostructures by incorporating a controllable interface-to-volume ratio, which is essential for optimization of the design and functionality of electronic devices.

3.
Magn Reson Imaging ; 31(7): 1174-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23642800

RESUMO

PURPOSE: This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation. MATERIALS AND METHODS: Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h-72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections. RESULTS: Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h-48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (P<0.05). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived on T2WI, DWI or CE-T1WI than ADC (P<0.05). At the last imaging time point, a significant increase in Evans Blue extravasation and a significant decrease in Nissl-positive cells numbers were noted in the vehicle-treated MCAO injured animals. The lesion volumes derived from T2WI, DWI, CE-T1WI, and Evans blue extravasation as well as the reduced numbers of Nissl-positive cells were all significantly attenuated in the agmatine-treated rats compared with the control ischemia rats (P<0.05). CONCLUSION: Our results suggest that agmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia.


Assuntos
Agmatina/uso terapêutico , Edema Encefálico/prevenção & controle , Infarto da Artéria Cerebral Média/prevenção & controle , Ataque Isquêmico Transitório/prevenção & controle , Imageamento por Ressonância Magnética/métodos , Fármacos Neuroprotetores/uso terapêutico , Animais , Edema Encefálico/patologia , Infarto Cerebral/patologia , Corantes/química , Meios de Contraste/química , Imagem de Difusão por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador , Infarto da Artéria Cerebral Média/patologia , Ataque Isquêmico Transitório/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Reperfusão , Fatores de Tempo
4.
Colorectal Dis ; 15(7): 807-11, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23350992

RESUMO

AIM: The accuracy of computed tomography (CT) in detecting local invasion (T status) and nodal metastasis (N status) of colon cancer was determined. METHOD: Data on the preoperative CT scan of 153 lesions from 152 patients with colon cancer were reviewed retrospectively. Evaluation included the T stage and N stage of the TNM system. The results were compared with those obtained by histopathological examination of the resected tumour. RESULTS: Of the 153 tumours, 117 (76.5%) were correctly classified as Stage T1 and T2 (33 tumours) and Stage T3 and T4 (84 tumours) by CT. The sensitivity and specificity were 70.2% and 79.2%, respectively, and the positive and negative predictive values were 85.7% and 60.0%. When analysed according to the individual T stage (Tx/Tis, T1, 2, 3, 4) and N stage (N0, 1, 2), the kappa coefficient with linear weighting was 0.208 (fair agreement) for T stage and 0.154 (slight agreement) for N stage. The estimation of tumour size showed good agreement with histopathology (Spearman correlation coefficient 0.865). CONCLUSION: CT scanning of colonic cancer showed 75% accuracy in identifying T1 and T2 cancers combined, but gave poor agreement between CT and histopathology for individual T stages.


Assuntos
Carcinoma/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Pólipos do Colo/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Tomografia Computadorizada por Raios X , Idoso , Carcinoma/diagnóstico , Carcinoma/patologia , Estudos de Coortes , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/patologia , Pólipos do Colo/diagnóstico , Pólipos do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Cell Prolif ; 45(5): 445-55, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22783948

RESUMO

OBJECTIVES: Cancer is a complex biological occurrence which is difficult to describe clearly and explain its growth development. As such, novel concepts, such as of heterogeneity and signalling pathways, grow exponentially and many mathematical models accommodating the latest knowledge have been proposed. Here, we present a simple mathematical model that exhibits many characteristics of experimental data, using prostate carcinoma cell spheroids under treatment. MATERIALS AND METHODS: We have modelled cancer as a two-subpopulation system, with one subpopulation representing a cancer stem cell state, and the other a normal cancer cell state. As a first approximation, these follow a logistical growth model with self and competing capacities, but they can transform into each other by using an autocrine signalling pathway. RESULTS AND CONCLUSION: By analysing regulation behaviour of each of the system parameters, we show that the model exhibits many characteristics of actual cancer growth curves. Features reproduced in this model include delayed phase of evolving cancer under 17AAG treatment, and bi-stable behaviour under treatment by irradiation. In addition, our interpretation of the system parameters corresponds well with known facts involving 17AAG treatment. This model may thus provide insight into some of the mechanisms behind cancer.


Assuntos
Comunicação Autócrina/fisiologia , Proliferação de Células , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/fisiologia , Comunicação Autócrina/efeitos dos fármacos , Comunicação Autócrina/efeitos da radiação , Benzoquinonas/farmacologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Lactamas Macrocíclicas/farmacologia , Modelos Logísticos , Fenótipo , Doses de Radiação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação
6.
J Fish Biol ; 81(2): 427-41, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22803718

RESUMO

Otolith Sr:Ca ratios of the African longfinned eel Anguilla mossambica and giant mottled eel Anguilla marmorata from nine freshwater sites in four rivers of South Africa were analysed to reconstruct their migratory life histories between freshwater and saltwater habitats. For A. mossambica, the Sr:Ca ratios in the otolith edge differed significantly among rivers and had large effect sizes, but did not differ among sites within a river. Otolith Sr:Ca ratios did not differ among rivers for A. marmorata. When rivers were pooled, the edge Sr:Ca ratios of A. mossambica were not significantly different from those of A. marmorata. According to the river-specific critical Sr:Ca ratio distinguishing freshwater from saltwater residence, most A. mossambica and A. marmorata had saltwater habitat experience after settlement in fresh water. This was primarily during their elver stage or early in the yellow eel stage. During the middle and late yellow eel stage, freshwater residency was preferred and only sporadic visits were made to saltwater habitats. The data also suggest that regional variations in otolith Sr:Ca ratios affect the critical Sr:Ca value and are a challenge for the reconstruction of migratory life histories that should be explicitly considered to avoid bias and uncertainty.


Assuntos
Anguilla/fisiologia , Migração Animal , Membrana dos Otólitos/fisiologia , Animais , Cálcio/análise , Ecossistema , Água Doce , Membrana dos Otólitos/química , Rios , Água do Mar , África do Sul , Estrôncio/análise
7.
J Fish Biol ; 78(3): 860-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21366578

RESUMO

Otolith Sr:Ca ratios from 32 of 34 European eel Anguilla anguilla collected from three freshwater sites in the River Asi, southern Turkey, indicated that they were resident in fresh water without apparent exposure to salt water since the elver stage. The Sr:Ca ratio criterion indicative of residence in fresh water was more than twice that of values from other European countries. Otolith Sr:Ca ratios of A. anguilla from fresh waters can vary among regions, possibly reflecting regional-specific water chemistry. Hence, the use of Sr:Ca ratios determined in one region to interpret results from a different region might lead to misclassification of migratory life-history types.


Assuntos
Migração Animal/fisiologia , Cálcio/análise , Enguias/fisiologia , Membrana dos Otólitos/química , Rios , Estrôncio/análise , Animais , Enguias/anatomia & histologia , Feminino , Masculino , Membrana dos Otólitos/fisiologia , Turquia
8.
J Fish Biol ; 75(1): 100-12, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20738485

RESUMO

Information theory was applied to select the best model fitting total length (L(T))-at-age data and calculate the averaged model for Japanese eel Anguilla japonica compiled from published literature and the differences in growth between sexes were examined. Five candidate growth models were the von Bertalanffy, generalized von Bertalanffy, Gompertz, logistic and power models. The von Bertalanffy growth model with sex-specific coefficients was best supported by the data and nearly overlapped the averaged growth model based on Akaike weights, indicating a similar fit to the data. The Gompertz, generalized von Bertalanffy and power growth models were also substantially supported by the data. The L(T) at age of A. japonica were larger in females than in males according to the averaged growth mode, suggesting a sexual dimorphism in growth. Model inferences based on information theory, which deal with uncertainty in model selection and robust parameter estimates, are recommended for modelling the growth of A. japonica.


Assuntos
Anguilla/crescimento & desenvolvimento , Teoria da Informação , Modelos Biológicos , Rios , Animais , Tamanho Corporal , Feminino , Masculino , Fatores Sexuais , Taiwan
9.
J Fish Biol ; 75(10): 2709-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738518

RESUMO

To examine the relationship between freshwater entry and otolith annular structures, a total of 113 naturally recruited European eels Anguilla anguilla from Lithuania and Latvia that entered fresh water at least once were collected. In some individuals (8.3-11.3%), the first freshwater entry coincided with a dark check that was distinctly different from neighbouring annuli. In most individuals (81.7-84.9%), the first freshwater entry occurred on rings and increments indistinguishable from other annuli. For the remaining individuals (3.8-10%), the first freshwater entry did not correspond to any otolith ring, band or annulus. According to recent evidence, the observed high correspondence between the first freshwater entry and otolith annuli was more likely due to the movement into fresh water during winter when the annulus was deposited, rather than stress resulting from habitat change. Consequently, the age estimation based on otoliths might be less influenced by this habitat change during the yellow eel stage.


Assuntos
Anguilla/anatomia & histologia , Migração Animal , Ecossistema , Membrana dos Otólitos/anatomia & histologia , Animais , Feminino , Água Doce , Letônia , Lituânia , Masculino , Estações do Ano
10.
J Fish Biol ; 75(2): 393-407, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20738545

RESUMO

The population genetic structure and historical demography of the flathead mullet Mugil cephalus were investigated using the mtDNA control region (CR) sequences (909-1015 bp) of 126 individuals collected from seven locations in the north-west Pacific between 2005 and 2007. Haplotype diversity (h = 0.9333-1.000) and nucleotide diversity (pi = 0.0046-0.1467) varied greatly among the sampling locations. Phylogenetic analysis of the CR sequences indicated that M. cephalus in the north-west Pacific belongs to two highly divergent lineages (lineages 1 and 2), with the inferred population structure being closely associated with the distribution of both lineages. Two populations were identified, one from the East China Sea and the other from the South China Sea. The former samples were obtained from Taiwan and Qingdao of north China and associated with lineage 1 haplotypes. The latter samples were collected from the Philippines, Pearl River of South China and two samples from Japan, all of which were associated with lineage 2. Japanese samples from Okinawa and Yokosuka had different degrees of mixing between lineages 1 and 2. Historical demographic variables in both populations indicated that Pleistocene glaciations had a strong impact on M. cephalus in the north-west Pacific, resulting in a recent demographic decline of the East China Sea population but in demographic equilibrium for the South China Sea population. Japan appears to be a contact zone between lineages 1 and 2, but it may also be indicative of coexistence between resident and migratory populations. Further global studies are required to clarify the taxonomic status of this cosmopolitan species.


Assuntos
DNA Mitocondrial/genética , Filogeografia , Smegmamorpha/classificação , Smegmamorpha/genética , Animais , Variação Genética , Genética Populacional , Haplótipos , Dados de Sequência Molecular , Oceano Pacífico , Filogenia , Dinâmica Populacional
11.
J Fish Biol ; 75(6): 1173-93, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20738607

RESUMO

The elements Na, Mg, Mn, Ca, Sr and Ba in otoliths of southern bluefin tuna Thunnus maccoyii, collected from their feeding ground in the central Indian Ocean and spawning ground between southern Java and north-western Australia were measured by laser-ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and compared among sampling locations and developmental stages. The Na, Mg and Mn to Ca concentration ratios were significantly higher at the larval stage than at the adult stage, and the ratio reached a peak at the first inflection point of the otolith, mean +/-s.d. 43.3 +/- 4.9 days after hatching and decreased sharply to a low level thereafter. The temporal change of the elements:Ca ratios in the first inflection point corresponded to the life stage transition from larva to juvenile, indicating that the uptake rate of elements from ambient waters was significantly influenced by the ontogenetic change in the fish. The elemental composition at the otolith edge differed significantly in sub-adults on the feeding grounds and adults on the spawning grounds. Thus, the otolith elemental composition can be used as a biological tracer to study the time of the ontogenetic shift and to reconstruct the past migratory environmental history of T. maccoyii. In addition, the elemental composition of the otolith core of the adult was similar between feeding and spawning grounds, indicating that the fish in the Indian Ocean had the same larval origin, which is consistent with the single spawning population hypothesis.


Assuntos
Biologia Marinha , Membrana dos Otólitos/química , Atum/metabolismo , Animais , Biomarcadores/análise , Oceano Índico , Fatores de Tempo , Atum/crescimento & desenvolvimento
12.
Opt Express ; 16(25): 20610-6, 2008 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-19065200

RESUMO

We report on the formation of organized sub-micron YBa(2)Cu(3)O(7) (YBCO) dots induced by irradiating femtosecond laser pulses on YBCO films prepared by pulse laser deposition with fluence in the range of 0.21 approximately 0.53 J/cm(2). The morphology of the YBCO film surface depends strongly on the laser fluences irradiated. At lower laser fluence (approximately 0.21 J/cm(2)) the morphology was pattern of periodic ripples with sub-micrometer spacing. Slightly increasing the laser fluence to 0.26 J/cm(2) changes the pattern into organized sub-micron dots with diameters ranging from 100 nm to 800 nm and height of 150 nm. Further increase of the laser fluence to over 0.32 J/cm(2), however, appeared to result in massive melting and led to irregular morphology. The mechanism and the implications of the current findings will be discussed. Arrays of YBCO sub-micron dots with T(c) = 89.7 K were obtained.


Assuntos
Lasers , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Doses de Radiação
13.
Australas Radiol ; 51 Spec No.: B74-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17875166

RESUMO

Epidermoid cysts, though having a variable sonographic appearance, may present with an onion peel configuration, that is, concentric rings of alternating hyperechogenicities and hypoechogenicities. The absence of vascular flow on colour Doppler sonography is also consistent with the avascular nature of these lesions. By combining these two sonographic features and the absence of biochemical tumour marker, preoperative diagnosis of epidermoid cyst is possible and may prompt a testis sparing surgery rather than orchidectomy.


Assuntos
Cisto Epidérmico/diagnóstico por imagem , Doenças Testiculares/diagnóstico por imagem , Testículo/diagnóstico por imagem , Adulto , Humanos , Masculino , Ultrassonografia
15.
Acta Radiol ; 47(7): 752-4, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16950717

RESUMO

Clinically symptomatic renal capsular leiomyomas are rare. Previous research has shown that these tumors are usually well-defined cystic lesions, solid lesions, or a mixture of the two. We report an unusual case of renal capsular leiomyoma which was well defined by ultrasonography, but lacked a well-defined edge in CT. The reason for the absence of a well-defined tumor edge is probably due to degeneration in certain parts of the tumor resulting in a different degree of enhancement. Thus, the possibility of renal capsular leiomyoma should be included in the differential diagnosis whenever a renal mass is found, especially when either CT or ultrasonography shows that the tumor has a smooth, well-defined contour.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Adulto , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Renais/cirurgia , Leiomioma/cirurgia , Nefrectomia , Tomografia Computadorizada por Raios X , Ultrassonografia
16.
Dis Aquat Organ ; 71(2): 101-8, 2006 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-16956057

RESUMO

The infection by swimbladder nematodes of the genus Anguillicola (Dracunculoidea: Anguillicolidae) was examined in 2 populations of the Japanese eel Anguilla japonica in SW Taiwan. Wild eels from the Kao-Ping river were compared with cultured eels from an adjacent aquaculture unit. Only the cosmopolitan species Anguillicola crassus was present. Among wild eels, prevalence of infection varied between 21 and 62%, and mean intensity between 1.7 and 2.7 for adult worms. Similar intensity values (1.3 to 2.8) were recorded for the larvae. In cultured eels, prevalence as well as mean intensities were higher. In the cultured hosts, mean larval intensities exceeded those of adult worms 2-fold, and maximum larval intensities were 4- to 5-fold higher than in eels from the river. In cultured eels, dead larvae were also more abundant than in wild eels. We conclude that infrapopulations of A. crassus in Japanese eels are regulated by the defense system of this host, intraspecific density-dependent regulation being less likely as the major regulatory mechanism. No influence of the parasite on eel condition was found in either wild or cultured eels, indicating a low or moderate pathogenic effect of A. crassus on this host. This study shows that A. crassus is moderately common in cultured and wild Japanese eels in Taiwan, where the parasite is endemic.


Assuntos
Anguilla/parasitologia , Dracunculoidea/isolamento & purificação , Doenças dos Peixes/epidemiologia , Infecções por Spirurida/veterinária , Sacos Aéreos/parasitologia , Animais , Animais Selvagens/parasitologia , Tamanho Corporal , Feminino , Doenças dos Peixes/parasitologia , Pesqueiros , Larva , Masculino , Prevalência , Rios , Estações do Ano , Infecções por Spirurida/epidemiologia , Taiwan/epidemiologia
17.
Food Chem Toxicol ; 44(5): 704-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16307839

RESUMO

Chalcones are discussed to represent cancer preventive food components in a human diet that is rich in fruits and vegetables. In this study, we examined chalcone (1,3-diphenyl-2-propenone) for its effect on proliferation in human breast cancer cell lines, MCF-7 and MDA-MB-231. The results showed that chalcone inhibited the proliferation of MCF-7 and MDA-MB-231 by inducing apoptosis and blocking cell cycle progression in the G2/M phase. Immunoblot assay showed that chalcone significantly decreased the expression of cyclin B1, cyclin A and Cdc2 protein, as well as increased the expression of p21 and p27 in a p53-independent manner, contributing to cell cycle arrest. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), was responsible for the apoptotic effect induced by chalcone. In addition, chalcone also triggered the mitochondrial apoptotic signaling by increasing the amount of Bax and Bak and reducing the level of Bcl-2 and Bcl-X(L), and subsequently activated caspase-9 in MCF-7 and MDA-MB-231 cells. Taken together, our study suggests that the blockade of cell cycle progression and initiation of cell apoptotic system may participate in the antiproliferative activity of chalcone in human breast cancer cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Chalcona/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Caspase 9 , Caspases/metabolismo , Ciclina A/metabolismo , Ciclina B/metabolismo , Ciclina B1 , Relação Dose-Resposta a Droga , Proteína Ligante Fas , Fase G2/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Immunoblotting , Glicoproteínas de Membrana/metabolismo , Mitose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas , Fatores de Necrose Tumoral/metabolismo , Proteína bcl-X/metabolismo
18.
Arch Virol ; 151(2): 327-46, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16172842

RESUMO

The subgenomic (SG) mRNA of rubella virus (RUB) contains the structural protein open reading frame (SP-ORF) that is translated to produce the three virion structural proteins: capsid (C) and glycoproteins E2 and E1. RUB expression vectors have been developed that express heterologous genes from the SG RNA, including replicons which replace the SP-ORF with a heterologous gene, and these expression vectors are candidate vaccine vectors. In the related alphaviruses, translational enhancing elements have been identified in both the 5' untranslated region (UTR) of the SG RNA and the N-terminal region of the C gene. To optimize expression from RUB vectors, both the 5'UTR of the SG RNA and the C gene were surveyed for translational enhancing elements using both plasmids and replicons expressing reporter genes from the SG RNA. In replicons, the entire 5'UTR was necessary for translation; interestingly, when plasmids were used the 5'UTR was dispensable for optimal translation. The RUB C gene contains a predicted long stem-loop starting 62 nts downstream from the initiation codon (SLL) that has a structure and stability similar to SL's found in the C genes of two alphaviruses, Sindbis virus (SIN) and Semliki Forest virus, that have been shown to enhance translation of the SG RNA in infected cells. However, a series of fusions of various lengths of the N-terminus of the RUB C protein with reporter genes showed that the SLL had an attenuating effect on translation that was overcome by mutagenesis that destabilized the SLL or by adding downstream sequences of the C gene to the fusion. Thus, for optimal expression efficiency from RUB expression vectors, only the 5'UTR of the SG RNA is required. Further investigation of the differing effects of the SLL on RUB and alphavirus SG RNA translation revealed that the SIN and RUB SLLs could enhance translation when expressed from a SIN cytopathic replicon, but not when expressed from a plasmid, a RUB replicon, or a SIN noncytopathic replicon. Thus, the SLL only functions in a "cytopathic environment" in which cell translation has been altered.


Assuntos
Genoma Viral , Biossíntese de Proteínas/genética , RNA Viral/metabolismo , Elementos de Resposta/genética , Vírus da Rubéola/genética , Vírus da Rubéola/metabolismo , Animais , Chlorocebus aethiops , RNA Viral/genética , Transcrição Gênica , Células Vero
20.
J Phys Chem A ; 109(42): 9481-7, 2005 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-16866397

RESUMO

The origin of the S(1) <-- S(0) transition (E(1)) and the adiabatic ionization energy (IE) of cis-p-methoxyphenol-d(1)-OD are determined to be 33 660 and 62 302 cm(-1), whereas those of cis-p-methoxyphenol-d(1)-OCH(2)D are 33 669 and 62 323 cm(-1), respectively. Similarly, the E(1) and IE of trans-p-methoxyphenol-d(1)-OD are determined to be 33 563 and 62 191 cm(-1) and those of trans-p-methoxyphenol-d(1)-OCH(2)D are 33 575 and 62 216 cm(-1), respectively. Comparing these data with those of p-methoxyphenol suggests that the H/D exchange on the OH substituent gives rise to a red shift in both the E(1) and IE, whereas that on the OCH(3) group yields a blue shift. The mass-analyzed threshold ionization spectra of the selected isomers can be used as the fingerprints for molecular identification. Analysis of these cation spectra shows that the substituent-sensitive in-plane C-OH and C-OCH(3) bending (mode 9b) and breathing (mode 1) vibrations are active for all of these isomeric cations.

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