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1.
Allergy ; 73(6): 1276-1283, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29319899

RESUMO

BACKGROUND: Frequent wheezing in original asthma predictive index (API) was defined by parental report of recurrent wheezing within 1 year during the first 3 years of life. The nature of frequent wheezing in children, particularly aged over 3 years, has not been studied. We aimed to assess the frequency and interval of wheezing to define frequent wheezing in ascertaining asthma for children using medical records. METHODS: Among children who participated in a previous study (n = 427), all wheezing episodes documented in medical records were collected for children who had ≥2 wheezing episodes PLUS met one major criterion or two minor criteria of API. We compared the distribution of known risk factors for asthma between subjects having two consecutive wheezing episodes with shorter interval (≤1 year) compared to those with longer interval (1 to 3 years). RESULTS: A total of 62 children met API at median age of 2.3 years. During follow-up period (median age: 11.3 years), a total of 198 wheezing episodes were observed. 81% of wheezing intervals were within 3 years from the earlier wheezing episode, including 60% within 1 year. Children who met API based on 1-year interval (n = 40) vs 1- to 3-year interval (n = 13) appeared to be similar in regard to the known risk factors for asthma. CONCLUSIONS: Our exploratory study finding suggests that children who had frequent wheezing episodes with longer interval (<3 years) need to be considered to be determined as asthma cases when API is applied to retrospective medical records. Prospective studies with a larger sample size need to replicate this finding.


Assuntos
Asma/epidemiologia , Asma/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Prontuários Médicos , Minnesota/epidemiologia , Prevalência , Vigilância em Saúde Pública , Sons Respiratórios , Estudos Retrospectivos , Fatores de Risco , Avaliação de Sintomas
2.
J Vet Pharmacol Ther ; 38(1): 86-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25229401

RESUMO

The study was aimed at investigating the pharmacokinetics of amoxicillin trihydrate (AMOX) in olive flounder (Paralichthys olivaceus) following oral, intramuscular, and intravenous administration, using high-performance liquid chromatography following. The maximum plasma concentration (Cmax ), following oral administration of 40 and 80 mg/kg body weight (b.w.), AMOX was 1.14 (Tmax , 1.7 h) and 0.76 µg/mL (Tmax , 1.6 h), respectively. Intramuscular administration of 30 and 60 mg/kg of AMOX resulted in Cmax values of 4 and 4.3 µg/mL, respectively, with the corresponding Tmax values of 29 and 38 h. Intravenous administration of 6 mg/kg AMOX resulted in a Cmax of 9 µg/mL 2 h after administration. Following oral administration of 40 and 80 mg/kg AMOX, area under the curve (AUC) values were 52.257 and 41.219 µg/mL·h, respectively. Intramuscular 30 and 60 mg/kg doses resulted in AUC values of 370.274 and 453.655 µg/mL·h, respectively, while the AUC following intravenous administration was 86.274 µg/mL·h. AMOX bioavailability was calculated to be 9% and 3.6% following oral administration of 40 and 80 mg/kg, respectively, and the corresponding values following intramuscular administration were 86% and 53%. In conclusion, this study demonstrated high bioavailability of AMOX following oral administration in olive flounder.


Assuntos
Amoxicilina/farmacocinética , Antibacterianos/farmacocinética , Linguado/sangue , Administração Oral , Amoxicilina/administração & dosagem , Amoxicilina/sangue , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Área Sob a Curva , Linguado/metabolismo , Meia-Vida , Injeções Intramusculares , Injeções Intravenosas
3.
J Fish Dis ; 35(3): 187-91, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22239254

RESUMO

It was recently reported that Poly(I:C) immunization with live nervous necrosis virus (NNV) confers protection in sevenband grouper, Epinephelus septemfasciatus (Thunberg), from NNV infection. In the present study, we conducted field tests with sevenband grouper for the evaluation of Poly(I:C) immunization efficacy. In the first experiment, sevenband grouper were immunized with NNV followed by Poly(I:C) administration 7 weeks before natural occurrence of viral nervous necrosis (VNN). Survival rate of the naïve fish was 71.0%, whereas that of the immunized fish was 99.8%. In the second experiment, sevenband grouper were immunized 10 months before VNN occurrence and survival rate of the non-treated and vaccinated fish was 79.5% and 97.5%, respectively. In the third experiment, we administered Poly(I:C) to sevenband grouper at 20 days after natural occurrence of VNN. The survival rate of the non-treated fish was 9.8%, whereas that of fish administered Poly(I:C) was 93.7%. Based on these results, it was concluded that Poly(I:C) immunization conferred protection in fish against NNV infection in field tests and the protection lasted more than 10 months. Furthermore, even after occurrence of VNN, fish mortality could be reduced by Poly(I:C) administration and there was an unexpected curative effect on VNN-affected fish.


Assuntos
Doenças dos Peixes/prevenção & controle , Imunização/veterinária , Poli I-C/administração & dosagem , Poli I-C/imunologia , Infecções por Vírus de RNA/prevenção & controle , Vacinas Virais/imunologia , Animais , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/mortalidade , Peixes , Nodaviridae , Infecções por Vírus de RNA/tratamento farmacológico , Infecções por Vírus de RNA/mortalidade , Fatores de Tempo
4.
Science ; 248(4958): 988-90, 1990 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-17745403

RESUMO

Coincidence counting techniques have been combined with time-of-flight mass spectrometry in the examination of surfaces for chemical microhomogeneity. A mathematical formalism was developed to describe the principles underlying this coincidence counting technique and was used to produce a quantitative method for handling the data obtained. This technique of testing for chemical homogeneity has been demonstrated with a sample that consists of a physical mixture of polystyrene and crystals of NaF which were tenths of micrometers in diameter. Ultimately this approach is expected to be useful for the routine testing of surfaces for chemical homogeneity at the level of tens of nanometers.

5.
BJA Educ ; 24(3): 91-99, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38375495
6.
Bone Joint J ; 101-B(6_Supple_B): 9-15, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31146571

RESUMO

AIMS: The aims of this study were to characterize antibiotic choices for perioperative total knee arthroplasty (TKA) and total hip arthroplasty (THA) prophylaxis, assess antibiotic allergy testing efficacy, and determine rates of prosthetic joint infection (PJI) based on perioperative antibiotic regimen. PATIENTS AND METHODS: We evaluated all patients undergoing primary TKA or THA at a single academic institution between January 2004 and May 2017, yielding 29 695 arthroplasties (22 705 patients), with 3411 arthroplasties in 2576 patients (11.5%) having undergone preoperative allergy testing. A series of institutional databases were combined to identify allergy consultation outcomes, perioperative antibiotic regimen, and infection-free survivorship until final follow-up. RESULTS: Among 2576 allergy-tested patients, 2493 patients (97%) were cleared to use cephalosporins. For the entire cohort, 28 174 arthroplasties (94.9%) received cefazolin and 1521 (5.1%) received non-cefazolin antibiotics. Infection-free survivorship was significantly higher among arthroplasties receiving cefazolin compared with non-cefazolin antibiotics, with 0.06% higher survival free of infection at one month, 0.56% at two months, 0.61% at one year, and 1.19% at ten years (p < 0.001). Overall, the risk of PJI was 32% lower in patients treated with cefazolin after adjusting for the American Society of Anesthesiologists (ASA) classification, joint arthroplasty (TKA or THA), and body mass index (BMI; p < 0.001). The number needed to treat with cefazolin to prevent one PJI was 164 patients at one year and 84 patients at ten years. Therefore, potentially 6098 PJIs could be prevented by one year and 11 905 by ten years in a cohort of 1 000 000 primary TKA and THA patients. CONCLUSION: PJI rates are significantly higher when non-cefazolin antibiotics are used for perioperative TKA and THA prophylaxis, highlighting the positive impact of preoperative antibiotic allergy testing to increase cefazolin usage. Given the low rate of true penicillin allergy positivity, and the readily modifiable risk factor that antibiotic choice provides, we recommend perioperative testing and clearance for all patients presenting with penicillin and cephalosporin allergies. Cite this article: Bone Joint J 2019;101-B(6 Supple B):9-15.


Assuntos
Antibacterianos/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Cefalosporinas/uso terapêutico , Prótese de Quadril/efeitos adversos , Prótese do Joelho/efeitos adversos , Infecções Relacionadas à Prótese/etiologia , Adulto , Idoso , Antibioticoprofilaxia , Cefazolina/uso terapêutico , Hipersensibilidade a Drogas/prevenção & controle , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle
8.
Phys Med Biol ; 60(18): 7127-49, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26334312

RESUMO

In Positron Emission Tomography, there are several causes of quantitative inaccuracy, such as partial volume or spillover effects. The impact of these effects is greater when using radionuclides that have a large positron range, e.g. (68)Ga and (124)I, which have been increasingly used in the clinic. We have implemented and evaluated a local projection algorithm (LPA), originally evaluated for SPECT, to compensate for both partial-volume and spillover effects in PET. This method is based on the use of a high-resolution CT or MR image, co-registered with a PET image, which permits a high-resolution segmentation of a few tissues within a volume of interest (VOI) centered on a region within which tissue-activity values need to be estimated. The additional boundary information is used to obtain improved activity estimates for each tissue within the VOI, by solving a simple inversion problem. We implemented this algorithm for the preclinical Argus PET/CT scanner and assessed its performance using the radionuclides (18)F, (68)Ga and (124)I. We also evaluated and compared the results obtained when it was applied during the iterative reconstruction, as well as after the reconstruction as a postprocessing procedure. In addition, we studied how LPA can help to reduce the 'spillover contamination', which causes inaccurate quantification of lesions in the immediate neighborhood of large, 'hot' sources. Quantification was significantly improved by using LPA, which provided more accurate ratios of lesion-to-background activity concentration for hot and cold regions. For (18)F, the contrast was improved from 3.0 to 4.0 in hot lesions (when the true ratio was 4.0) and from 0.16 to 0.06 in cold lesions (true ratio = 0.0), when using the LPA postprocessing. Furthermore, activity values estimated within the VOI using LPA during reconstruction were slightly more accurate than those obtained by post-processing, while also visually improving the image contrast and uniformity within the VOI.


Assuntos
Algoritmos , Radioisótopos de Gálio/farmacocinética , Radioisótopos do Iodo/farmacocinética , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Distribuição Tecidual
9.
Phys Med Biol ; 60(1): 117-36, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25479147

RESUMO

Although current PET scanners are designed and optimized to detect double coincidence events, there is a significant amount of triple coincidences in any PET acquisition. Triple coincidences may arise from causes such as: inter-detector scatter (IDS), random triple interactions (RT), or the detection of prompt gamma rays in coincidence with annihilation photons when non-pure positron-emitting radionuclides are used (ß(+)γ events). Depending on the data acquisition settings of the PET scanner, these triple events are discarded or processed as a set of double coincidences if the energy of the three detected events is within the scanner's energy window. This latter option introduces noise in the data, as at most, only one of the possible lines-of-response defined by triple interactions corresponds to the line along which the decay occurred. Several novel works have pointed out the possibility of using triple events to increase the sensitivity of PET scanners or to expand PET imaging capabilities by allowing differentiation between radiotracers labeled with non-pure and pure positron-emitting radionuclides. In this work, we extended the Monte Carlo simulator PeneloPET to assess the proportion of triple coincidences in PET acquisitions and to evaluate their possible applications. We validated the results of the simulator against experimental data acquired with a modified version of a commercial preclinical PET/CT scanner, which was enabled to acquire and process triple-coincidence events. We used as figures of merit the energy spectra for double and triple coincidences and the triples-to-doubles ratio for different energy windows and radionuclides. After validation, the simulator was used to predict the relative quantity of triple-coincidence events in two clinical scanners assuming different acquisition settings. Good agreement between simulations and preclinical experiments was found, with differences below 10% for most of the observables considered. For clinical scanners and pure positron emitters, we found that around 10% of the processed double events come from triple coincidences, increasing this ratio substantially for non-pure emitters (around 25% for (124)I and > 50% for (86)Y). For radiotracers labeled with (18)F we found that the relative quantity of IDS events in standard acquisitions is around 18% for the preclinical scanner and between 14 and 22% for the clinical scanners. For non-pure positron emitters like (124)I, we found a ß(+)γ triples-to-doubles ratio of 2.5% in the preclinical scanner and of up to 4% in the clinical scanners.


Assuntos
Simulação por Computador , Raios gama , Imagens de Fantasmas , Fótons , Tomografia por Emissão de Pósitrons/métodos , Animais , Partículas beta , Humanos , Radioisótopos do Iodo , Camundongos , Método de Monte Carlo , Tomógrafos Computadorizados
10.
J Mol Endocrinol ; 33(1): 195-207, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15291753

RESUMO

We have used quantitative RT-PCR to analyse the mRNA expression profile of the major components of the IGF axis in different stages of murine mammary gland development, including late pregnancy, lactation and involution. We have shown that all the genes studied, IGF-I, IGF-II, IGF receptor (IGFR) and IGF-binding protein (IGFBP)-1 to -6, were expressed in every stage, albeit at greatly differing levels and displaying unique expression profiles between developmental stages. IGF-I was always expressed at significantly higher levels than either IGF-II or IGFR. This suggests that IGF-I may be the more important IGF during mammary morphogenesis. Overall, IGFBP-3 demonstrated the highest level of expression of any of the IGFBP genes throughout all the developmental stages studied. However, within developmental stages, by far the highest level of expression of any of the IGFBPs was that of IGFBP-5 at day 2 of involution; this was almost an order of magnitude higher than any of the other IGFBP levels recorded. This corroborated our previous findings that the levels of IGFBP-5 protein are highly elevated in the involuting mammary gland, and demonstrated that this up-regulation of IGFBP-5 operates at the level of transcriptional control or message stability. Comparison of the expression profile for these different genes would strongly suggest that they are likely to have differential functions throughout mammary gland development, and also highlights potential interactions and co-regulation between different members of this axis. In addition, our results have identified some similarities and differences in the expression of IGFBPs between the mouse mammary epithelial cell line, HC11, and the normal mammary gland which are worthy of study, most notably the differential regulation of IGFBP-2 and the site of expression of IGFBP-4 and -6. Overall, this study has demonstrated the importance and complexity of the IGF axis during mammary gland development and provides a valuable resource for future research in this area.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Fator de Crescimento Insulin-Like I/genética , Glândulas Mamárias Animais/metabolismo , RNA Mensageiro/genética , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
J Mol Endocrinol ; 31(1): 197-208, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12914536

RESUMO

The mouse mammary epithelial cell line HC11 upregulates the synthesis of beta-casein (a differentiation marker) following treatment with the lactogenic hormone mix dexamethasone, insulin and prolactin (DIP). We demonstrate that the basal levels of IGF-binding protein (IGFBP)-5 secreted by undifferentiated HC11 cells are upregulated 10-fold during DIP-induced cellular differentiation whereas the level of the other IGFBP species secreted by HC11 cells (IGFBP-2) is downregulated during this process. As previously reported, the combination of all three of these hormones is required for synthesis of the differentiation marker beta-casein, whereas basal IGFBP-5 secretion is evident in the absence of any hormonal treatment and, unlike beta-casein, secretion of this protein can be stimulated by binary combinations of the hormones (although maximal levels of IGFBP-5 are achieved in the presence of all three lactogenic hormones). Additionally, levels of IGFBP-5 can be increased by DIP treatment under conditions (non-competency of HC11 cultures or presence of epidermal growth factor) where DIP treatment does not increase synthesis of beta-casein. For IGFBP-2, dexamethasone is a potent inhibitor of secretion whilst prolactin stimulated the secretion of this binding protein into the medium. For the IGFBP axis in HC11 cells we conclude that, although the levels of IGFBP-5 and -2 are influenced by the state of cellular differentiation, the hormonal regulation of the levels of these IGFBP species can be dissociated from the regulation of beta-casein synthesis. In a further series of experiments we demonstrate that IGF-I is able to replace insulin in the DIP lactogenic hormone mix and by the use of a specific IGF-I receptor blocking antibody indicate that the action of IGF-I is mediated through the cell surface IGF-I receptor and not by cross-reaction of IGF-I ligand at the insulin receptor. We discuss our data in the context of the potential role of the IGF axis in the process of cell differentiation and illustrate the significance of our findings in the context of the physiology and life cycle of the mammary epithelial cell.


Assuntos
Células Epiteliais/citologia , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Insulina/farmacologia , Glândulas Mamárias Animais/fisiologia , Prolactina/farmacologia , Animais , Diferenciação Celular , Linhagem Celular , Dexametasona/farmacologia , Interações Medicamentosas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Feminino , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/efeitos dos fármacos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/efeitos dos fármacos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Camundongos
12.
Exp Mol Med ; 32(3): 170-7, 2000 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-11048649

RESUMO

Phospholipase D (PLD) is an enzyme involved in signal transduction and widely distributed in mammalian cells. The signal transduction pathways and role for phospholipid metabolism during hormonal response in cortical collecting duct remain partly undefined. It has been reported that dexamethasone increases transepithelial transport in M-1 cells that are derived from the mouse cortical collecting duct. We investigated the expression and activity of PLD in M-1 cells. Basal PLD activity of M-1 cells cultured in the presence of dexamethasone (5 microM) was higher than in the absence of dexamethasone. Dexamethasone and ATP activated PLD in M-1 cells but phorbol ester did not stimulate PLD activity. Vasopressin, bradykinin, dibutyryl cyclic AMP, and ionomycin were ineffective in activating PLD of the cells. The PLD2 isotype was detected by immunoprecipitation but PLD1 was not detected in M-1 cells. Addition of GTPgammaS and ADP-ribosylation factor or phosphatidylinositiol 4,5-bisphosphate to digitonin-permeabilized cells did not augment PLD activity. In intact cells PLD activity was increased by sodium oleate but there was no significant change between dexamethasone treated- and untreated cells by oleate. These results suggest that at least two types of PLD are present in M-1 cells and PLD plays a role in the corticosteroid-mediated response of cortical collecting duct cells.


Assuntos
Dexametasona/farmacologia , Túbulos Renais Coletores/efeitos dos fármacos , Fosfolipase D/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Glicerofosfolipídeos/análise , Isoenzimas/efeitos dos fármacos , Córtex Renal/citologia , Túbulos Renais Coletores/citologia , Camundongos , Camundongos Transgênicos , Ácido Oleico/farmacologia
13.
Adv Exp Med Biol ; 403: 571-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8915395

RESUMO

i. Taurine concentrations of human milk of nonvegetarians and lacto-ovovegetarians decreased significantly during the course of lactation. Taurine concentrations in lacto-ovovegetarians after 90 days postpartum were lower than those of nonvegetarians. Taurine concentrations of human milk by 150 days postpartum were: nonvegetarian 248-434 nmol/ml (31.0-54.4 mg/L); lacto-ovovegetarian 153-418 nmol/ml (19.1-52.3 mg/L). ii. Taurine intakes in infants of lacto-ovovegetarians decreased significantly during lactation, unlike from the pattern in infants of nonvegetarians. Taurine intakes in infants of lacto-ovovegetarians at 90, 120 and 150 days postpartum were lower, compared with those in nonvegetarians. Taurine intakes in infants by 150 days postpartum were: Infants of nonvegetarians 169-229 mumol/day (21.1-28.6 mg/day); Infants of lacto-ovovegetarians 106-210 mumol/day (21.1-28.6 mg/day). iii. This study showed that the taurine concentration in human milk and the taurine intake of infants were different during lactation between nonvegetarians and lacto-ovovegetarians, and that the intake per kg body weight decreased during lactation. Results suggest that the differences observed might be due to the effect of consumption of different types of food.


Assuntos
Aleitamento Materno , Leite Humano/química , Taurina/metabolismo , Dieta Vegetariana , Feminino , Humanos , Lactente , Recém-Nascido , Coreia (Geográfico) , Lactação/fisiologia , Valores de Referência , Taurina/análise , Fatores de Tempo
14.
Anal Methods ; 6(23): 9328-9332, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25558291

RESUMO

In the present paper, we showed the advantages of trapped ion mobility spectrometry coupled too mass spectrometry (TIMS-MS) combined with theoretical calculations for fast identification (millisecond timescale) of polycyclic aromatic hydrocarbons (PAH) compounds from complex mixtures. Accurate PAH collision cross sections (CCS, in nitrogen as a bath gas) are reported for the most commonly encountered PAH compounds and the ability to separate PAH geometric isomers is shown for three isobaric pairs with mobility resolution exceeding 150 (3-5 times higher than conventional IMS devices). Theoretical candidate structures (optimized at the DFT/B3LYP level) are proposed for the most commonly encountered PAH compounds showing good agreement with the experimental CCS values (<5%). The potential of TIMS-MS for the separation and identification of PAH compounds from complex mixtures without the need of lengthy pre-separation steps is illustrated for the case of a complex soil mixture.

15.
Cell Death Dis ; 5: e1231, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24832603

RESUMO

Lymphangioleiomyomatosis (LAM) is a female-predominant interstitial lung disease that can lead to respiratory failure. LAM cells typically have inactivating TSC2 mutations, leading to mTORC1 activation. The gender specificity of LAM suggests that estradiol contributes to disease development, yet the underlying pathogenic mechanisms are not completely understood. Using metabolomic profiling, we identified an estradiol-enhanced pentose phosphate pathway signature in Tsc2-deficient cells. Estradiol increased levels of cellular NADPH, decreased levels of reactive oxygen species, and enhanced cell survival under oxidative stress. Mechanistically, estradiol reactivated Akt in TSC2-deficient cells in vitro and in vivo, induced membrane translocation of glucose transporters (GLUT1 or GLUT4), and increased glucose uptake in an Akt-dependent manner. (18)F-FDG-PET imaging demonstrated enhanced glucose uptake in xenograft tumors of Tsc2-deficient cells from estradiol-treated mice. Expression array study identified estradiol-enhanced transcript levels of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway. Consistent with this, G6PD was abundant in xenograft tumors and lung metastatic lesions of Tsc2-deficient cells from estradiol-treated mice. Molecular depletion of G6PD attenuated estradiol-enhanced survival in vitro, and treatment with 6-aminonicotinamide, a competitive inhibitor of G6PD, reduced lung colonization of Tsc2-deficient cells. Collectively, these data indicate that estradiol promotes glucose metabolism in mTORC1 hyperactive cells through the pentose phosphate pathway via Akt reactivation and G6PD upregulation, thereby enhancing cell survival under oxidative stress. Interestingly, a strong correlation between estrogen exposure and G6PD was also found in breast cancer cells. Targeting the pentose phosphate pathway may have therapeutic benefit for LAM and possibly other hormonally dependent neoplasms.


Assuntos
Neoplasias da Mama/enzimologia , Estradiol/metabolismo , Linfangioleiomiomatose/enzimologia , Complexos Multiproteicos/metabolismo , Via de Pentose Fosfato , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Implantes de Medicamento , Ativação Enzimática , Estradiol/administração & dosagem , Feminino , Perfilação da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Humanos , Linfangioleiomiomatose/genética , Linfangioleiomiomatose/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Metabolômica , Camundongos , Camundongos SCID , NADP/metabolismo , Estresse Oxidativo , Interferência de RNA , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fatores de Tempo , Transfecção , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética
16.
Anaesth Intensive Care ; 41(3): 349-58, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23659397

RESUMO

This study compares the accuracy and capabilities of various ventilators using a paediatric acute respiratory distress syndrome lung model. Various compliance settings and respiratory rate settings were used. The study was done in three parts: tidal volume and FiO2 accuracy; pressure control accuracy and positive end-expiratory pressure (PEEP) accuracy. The parameters set on the ventilator were compared with either or both of the measured parameters by the test lung and the ventilator. The results revealed that none of the ventilators could consistently deliver tidal volumes within 1 ml/kg of the set tidal volume, and the discrepancy between the delivered volume and the volume measured by the ventilator varied greatly. The target tidal volume was 8 ml/kg, but delivered tidal volumes ranged from 3.6-11.4 ml/kg and the volumes measured by the ventilator ranged from 4.1-20.6 ml/kg. All the ventilators maintained pressure within 20% of the set pressure, except one ventilator which delivered pressures of up to 27% higher than the set pressure. Two ventilators maintained PEEP within 10% of the prescribed PEEP. The majority of the readings were also within 10%. However, three ventilators delivered, at times, PEEPs over 20% higher. In conclusion, as lung compliance decreases, especially in paediatric patients, some ventilators perform better than others. This study highlights situations where ventilators may not be able to deliver, nor adequately measure, set tidal volumes, pressure, PEEP or FiO2.


Assuntos
Respiração Artificial/métodos , Ventiladores Mecânicos , Pressão do Ar , Criança , Desenho de Equipamento , Humanos , Complacência Pulmonar/fisiologia , Medidas de Volume Pulmonar , Modelos Biológicos , Oxigênio/sangue , Respiração com Pressão Positiva , Reprodutibilidade dos Testes , Síndrome do Desconforto Respiratório/terapia , Taxa Respiratória , Volume de Ventilação Pulmonar
17.
Rev Sci Instrum ; 82(12): 126106, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22225261

RESUMO

The integration of a trapped ion mobility spectrometer (TIMS) with a mass spectrometer (MS) for complementary fast, gas-phase mobility separation prior to mass analysis (TIMS-MS) is described. The ion transmission and mobility separation are discussed as a function of the ion source condition, bath gas velocity, analysis scan speed, RF ion confinement, and downstream ion optical conditions. TIMS mobility resolution depends on the analysis scan speed and the bath gas velocity, with the unique advantage that the IMS separation can be easily tuned from high speed (~25 ms) for rapid analysis to slower scans for higher mobility resolution (R > 80).


Assuntos
Espectrometria de Massas/métodos , Integração de Sistemas , Espectrometria de Massas/instrumentação , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
20.
Arch Virol ; 150(2): 351-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15549489

RESUMO

Ten iridoviruses were isolated from cultured fish from various regions in Korea; 7 from rock bream, 1 from red sea bream, 1 from sea bass, and 1 from rockfish. The full open-reading frame (ORF) encoding the major capsid protein (MCP) (1362 bp) from ten iridoviruses were sequenced and the nucleotide sequences were phylogenetically analyzed. Phylogenetic analysis revealed that the ten Korean isolates were classified into one cluster. However, their sequences were not identical and, based on the nucleotide sequence variation, they could be further divided into two subgroups. While nine Korean isolates were similar to the Japanese isolate red sea bream iridovirus (RSIV), one isolate was distinct from other iridovirus isolates. These results suggest that a diversity of iridoviruses exist in Korea and that a new variant strain has emerged.


Assuntos
Proteínas do Capsídeo/genética , Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/virologia , Iridoviridae/genética , Sequência de Aminoácidos , Animais , Infecções por Vírus de DNA/virologia , Peixes , Genes Virais , Variação Genética , Iridoviridae/isolamento & purificação , Coreia (Geográfico) , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Alinhamento de Sequência
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