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1.
Pediatr Surg Int ; 39(1): 262, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668756

RESUMO

INTRODUCTION: Central venous catheter (CVC) placement is commonly performed in children. We aim to develop simple formulas to predict CVC intravascular length to minimise radiation exposure associated with the procedure. METHODS: 124 paediatric patients who received tunnelled neck CVCs and subsequent CT thorax at Hong Kong Children's Hospital from January 2020 to July 2022 were reviewed retrospectively. Formula development cohorts were subdivided by insertion sites-9 right external jugular vein (REJV), 41 right internal jugular vein (RIJV), 14 left external jugular vein (LEJV), 10 left internal jugular vein (LIJV). Using measurements from CT by two radiologists, formulas predicting the CVC intravascular length based on height and insertion sites were developed using a linear regression model. These formulas were tested with validation cohorts (10 randomly selected cases in REJV and RIJV groups respectively). Validation cohorts were not available for LEJV and LIJV groups due to small sample sizes. RESULT: The goodness-of-fit (R^2) of all formulas are above 0.8. In the validation cohorts, the REJV formula was predictive of intravascular CVC length within 1 cm in 70% of CVC with mean absolute difference of 0.63 cm (SD 0.48 cm), and the RIJV formula was predictive of intravascular CVC length within 1 cm in 80% of CVC with mean absolute difference of 0.67 cm (SD 0.53 cm). CONCLUSION: Intravascular CVC length can be estimated using simple formulas based on height and insertion sites. Further prospective validation of the LEJV and LIJV formulas is needed.


Assuntos
Cateteres Venosos Centrais , Humanos , Criança , Estudos Retrospectivos , Veias Braquiocefálicas , Hospitais Pediátricos , Veias Jugulares/diagnóstico por imagem
3.
Sci Total Environ ; 880: 163268, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031935

RESUMO

The spatial distribution and abundance of suspected microplastics (SMPs) in the surface water of a metropolitan city, as represented by four Hong Kong rivers, was studied during the dry season. Shing Mun River (SM), Lam Tsuen River (LT), and Tuen Mun River (TM) are located in urbanized areas, and SM and TM are tidal rivers. The fourth river, Silver River (SR) is situated in a rural area. TM had a significantly higher SMP abundance (53.80 ± 20.67 n/L) than the other rivers. The SMP abundance increased from upstream to downstream in non-tidal rivers (LT and SR), but not in tidal rivers (TM and SM), probably due to the tidal influence and a more homogeneous urban development along the tidal rivers. Inter-site differences in the SMP abundance were strongly correlated with the built area ratio (defined as the percentage of surrounding developed land area), human activities, and the nature of the river. About half (48.72 %) of the SMPs were <250 µm. Fibers and fragments were most abundant (>98 %), with most of them being transparent (58.54 %), black (14.68 %), or blue (12.12 %). Polyethylene terephthalate (26.96 %) and polyethylene (20.70 %) were the most common polymers. However, the MP abundance could be overestimated due to the presence of natural fibers. By contrast, an underestimation of the MP abundance could result from a smaller volume of water samples collected, due to a low filtration efficiency caused by high organic content and particle concentrations in the water. A more effective solid waste management strategy and upgrading of the sewage treatment facilities for removing microplastics are recommended to ameliorate the microplastic pollution in local rivers.

7.
Nature ; 563(7732): 527-531, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30397345

RESUMO

Quantum error correction is essential for realizing the full potential of large-scale quantum information processing devices1,2. Fundamental to its experimental realization is the repetitive detection of errors via projective measurements of quantum correlations among qubits, as well as corrections using conditional feedback3. Repetitive application of such tasks requires that they neither induce unwanted crosstalk nor impede further control operations, which is challenging owing to the need to dissipatively couple qubits to the classical world for detection and reinitialization. For trapped ions, state readout involves scattering large numbers of resonant photons, which increases the probability of stray light causing errors on nearby qubits and leads to undesirable recoil heating of the ion motion. Here we demonstrate up to 50 sequential measurements of correlations between two beryllium ion microwave qubits using an ancillary optical qubit in a calcium ion, and implement feedback that allows us to stabilize two-qubit subspaces as well as Bell states, a class of maximally entangled states. Multi-qubit mixed-species gates are used to transfer information within the register from the qubit to the ancilla, enabling readout with negligible crosstalk to the data qubits. Heating of the ion motion during detection is mitigated by recooling all three ions using light that interacts with only the calcium ion, known as sympathetic cooling. A key element of our experimental setup is a powerful classical control system that features flexible in-sequence processing for feedback control. The methods employed here provide essential tools for scaling trapped-ion quantum computing, quantum-state control and entanglement-enhanced quantum metrology4.

8.
Phys Rev Lett ; 119(3): 033602, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28777614

RESUMO

We demonstrate control of a trapped-ion quantum harmonic oscillator in a squeezed Fock state basis, using engineered Hamiltonians analogous to the Jaynes-Cummings and anti-Jaynes-Cummings forms. We demonstrate that for squeezed Fock states with low n the engineered Hamiltonians reproduce the sqrt[n] scaling of the matrix elements which is typical of Jaynes-Cummings physics, and also examine deviations due to the finite wavelength of our control fields. Starting from a squeezed vacuum state, we apply sequences of alternating transfer pulses which allow us to climb the squeezed Fock state ladder, creating states up to excitations of n=6 with up to 8.7 dB of squeezing, as well as demonstrating superpositions of these states. These techniques offer access to new sets of states of the harmonic oscillator which may be applicable for precision metrology or quantum information science.

9.
Mar Pollut Bull ; 124(2): 798-802, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28038767

RESUMO

The effects of microplastic concentrations (10itemsl-1 and 1000itemsl-1) on the physiological responses of Atactodea striata (clearance rate, absorption efficiency, respiration rate) were investigated. The fates of ingested microplastics and the efficiency of depuration in removing ingested microplastics were also studied. A. striata ingested microplastics and the clearance rate was reduced at high concentration of microplastics. Since the respiration rate and absorption efficiency remained unchanged in exposed A. striata, reduction in the clearance rate would reduce the energy intake. Ingestion and retention of microplastics in the body were further limited by the production of pseudofaeces and faeces, and depuration in clean water, resulting in a very small amount of microplastics stored in the body of the clam.


Assuntos
Bivalves/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Plásticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Respiração Celular , Fezes/química , Plásticos/análise , Plásticos/toxicidade , Alimentos Marinhos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
Cell Death Discov ; 2: 16027, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551518

RESUMO

Colorectal cancer (CRC) is the second leading cause of cancer-related death in males and females in the world. It is of immediate importance to develop novel therapeutics. Human ribonucleotide reductase (RRM1/RRM2) has an essential role in converting ribonucleoside diphosphate to 2'-deoxyribonucleoside diphosphate to maintain the homeostasis of nucleotide pools. RRM2 is a prognostic biomarker and predicts poor survival of CRC. In addition, increased RRM2 activity is associated with malignant transformation and tumor cell growth. Bioinformatics analyses show that RRM2 was overexpressed in CRC and might be an attractive target for treating CRC. Therefore, we attempted to search novel RRM2 inhibitors by using a gene expression signature-based approach, connectivity MAP (CMAP). The result predicted GW8510, a cyclin-dependent kinase inhibitor, as a potential RRM2 inhibitor. Western blot analysis indicated that GW8510 inhibited RRM2 expression through promoting its proteasomal degradation. In addition, GW8510 induced autophagic cell death. In addition, the sensitivities of CRC cells to GW8510 were associated with the levels of RRM2 and endogenous autophagic flux. Taken together, our study indicates that GW8510 could be a potential anti-CRC agent through targeting RRM2.

11.
Waste Manag Res ; 34(7): 619-29, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27231132

RESUMO

The organic content of municipal solid waste has long been an attractive source of renewable energy, mainly as a solid fuel in waste-to-energy plants. This study focuses on the potential to use microbial fuel cells to convert municipal solid waste organics into energy using various operational conditions. The results showed that two-chamber microbial fuel cells with carbon felt and carbon felt allocation had a higher maximal power density (20.12 and 30.47 mW m(-2) for 1.5 and 4 L, respectively) than those of other electrode plate allocations. Most two-chamber microbial fuel cells (1.5 and 4 L) had a higher maximal power density than single-chamber ones with corresponding electrode plate allocations. Municipal solid waste with alkali hydrolysis pre-treatment and K3Fe(CN)6 as an electron acceptor improved the maximal power density to 1817.88 mW m(-2) (~0.49% coulomb efficiency, from 0.05-0.49%). The maximal power density from experiments using individual 1.5 and 4 L two-chamber microbial fuel cells, and serial and parallel connections of 1.5 and 4 L two-chamber microbial fuel cells, was found to be in the order of individual 4 L (30.47 mW m(-2)) > serial connection of 1.5 and 4 L (27.75) > individual 1.5 L (20.12) > parallel connection of 1.5 and 4 L (17.04) two-chamber microbial fuel cells . The power density using municipal solid waste microbial fuel cells was compared with information in the literature and discussed.


Assuntos
Eletricidade , Resíduos Sólidos , Fontes de Energia Bioelétrica , Esgotos
12.
Int J Tuberc Lung Dis ; 20(3): 376-82, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27046720

RESUMO

SETTING: The Bureau of National Health Insurance (NHI) has implemented a pay-for-performance (p4p) programme for diabetes mellitus (DM) in Taiwan. OBJECTIVE: To investigate whether patients with DM enrolled in the p4p programme (DM-p4p) are less likely to develop tuberculosis (TB) and whether they have a better outcome than patients with DM not enrolled in the p4p programme (DM-non-p4p) if they do develop TB. DESIGN: A random sample of 79,471 DM-p4p, 100,000 DM-non-p4p and 100,000 non-diabetic patients (non-DM) was obtained from the 2008-2009 NHI database, and the patients were matched with the National TB Registry to determine whether they had developed TB by the end of 2010. RESULTS: The average annual incidence of TB was respectively 259.9 (95%CI 230.2-293.4), 137.5 (95%CI 116.4-162.5) and 74.1 (95%CI 59.0-93.0) per 100,000 population among DM-non-p4p, DM-p4p and non-DM patients. The relative risk of death over treatment success was 1.79 (95%CI 1.05-3.04) among DM-non-p4p and 1.69 (95%CI 0.84-3.40) among non-DM patients, relative to DM-p4p patients. CONCLUSIONS: Enhanced case management of DM reduced risk and improved outcomes of TB among patients with DM.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Gerenciamento Clínico , Tuberculose/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Comorbidade , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Programas Nacionais de Saúde , Reembolso de Incentivo , Fatores de Risco , Taiwan , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia
13.
Nat Commun ; 7: 11218, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27075230

RESUMO

The Hamiltonian of a closed quantum system governs its complete time evolution. While Hamiltonians with time-variation in a single basis can be recovered using a variety of methods, for more general Hamiltonians the presence of non-commuting terms complicates the reconstruction. Here using a single trapped ion, we propose and experimentally demonstrate a method for estimating a time-dependent Hamiltonian of a single qubit. We measure the time evolution of the qubit in a fixed basis as a function of a time-independent offset term added to the Hamiltonian. The initially unknown Hamiltonian arises from transporting an ion through a static laser beam. Hamiltonian estimation allows us to estimate the spatial beam intensity profile and the ion velocity as a function of time. The estimation technique is general enough that it can be applied to other quantum systems, aiding the pursuit of high-operational fidelities in quantum control.

14.
Phys Rev Lett ; 116(14): 140402, 2016 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-27104686

RESUMO

We directly observe the quantum interference between two well-separated trapped-ion mechanical oscillator wave packets. The superposed state is created from a spin-motion entangled state using a heralded measurement. Wave packet interference is observed through the energy eigenstate populations. We reconstruct the Wigner function of these states by introducing probe Hamiltonians which measure Fock state populations in displaced and squeezed bases. Squeezed-basis measurements with 8 dB squeezing allow the measurement of interference for Δα=15.6, corresponding to a distance of 240 nm between the two superposed wave packets.

15.
Insect Biochem Mol Biol ; 64: 68-77, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26226650

RESUMO

Phenoloxidases (POs) play key roles in various physiological functions in insects, e.g., cuticular sclerotization, wound healing, egg tanning, cuticle formation and melanotic encapsulaction of pathogens. Previously, we identified five POs, designated As-pro-PO I-V, from the mosquito Armigeres subalbatus and demonstrated that the functions of As-pro-PO I, II and III, were associated with filarial parasite melanization, blood feeding and cuticle formation, respectively. In the present study, we delineate the dual functions of As-pro-PO V. We found that the level of As-pro-PO V mRNA in mosquitoes was significantly increased after microfilaria challenge or blood feeding, and decreased to normal level after oviposition. Knockdown of As-pro-PO V by dsRNA resulted in significant decreases in the degree of microfilaria melanization, egg chronic melanization rates and egg hatching rates in Ar. subalbatus. Further transfection and electrophoretic mobility-shift assays verified the As-pro-PO V gene might regulated by both AP-1, a putative immune-related regulatory element and CdxA, a developmental regulatory element. The binding of AP-1 and CdxA motif with mosquito nuclear extracts was significantly enhanced after microfilaria challenge and blood-feeding in Ar. subalbatus, respectively. These results indicate that As-pro-PO V is a critical enzyme that is required for both an effective melanization immune response and egg chorion melanization in this mosquito.


Assuntos
Catecol Oxidase/metabolismo , Culicidae/parasitologia , Dirofilaria immitis/metabolismo , Precursores Enzimáticos/metabolismo , Melaninas/metabolismo , Animais , Sangue , Catecol Oxidase/genética , Córion/metabolismo , Cães , Precursores Enzimáticos/genética , Feminino , Óvulo/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo
16.
Oncogene ; 34(37): 4890-900, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25659578

RESUMO

The median survival time of breast cancer patients with brain metastasis is less than 6 months, and even a small metastatic lesion often causes severe neurological disabilities. Because of the location of metastatic lesions, a surgical approach is limited and most chemotherapeutic drugs are ineffective owing to the blood brain barrier (BBB). Despite this clinical importance, the molecular basis of the brain metastasis is poorly understood. In this study, we have isolated RNA from samples obtained from primary breast tumors and also from brain metastatic lesions followed by microRNA profiling analysis. Our results revealed that the miR-509 is highly expressed in the primary tumors, whereas the expression of this microRNA is significantly decreased in the brain metastatic lesions. MicroRNA target prediction and the analysis of cytokine array for the cells ectopically expressed with miR-509 demonstrated that this microRNA was capable of modulating the two genes essential for brain invasion, RhoC and TNF-α that affect the invasion of cancer cells and permeability of BBB, respectively. Importantly, high levels of TNF-α and RhoC-induced MMP9 were significantly correlated with brain metastasis-free survival of breast cancer patients. Furthermore, the results of our in vivo experiments indicate that miR-509 significantly suppressed the ability of cancer cells to metastasize to the brain. These findings suggest that miR-509 has a critical role in brain metastasis of breast cancer by modulating the RhoC-TNF-α network and that this miR-509 axis may represent a potential therapeutic target or serve as a prognostic tool for brain metastasis.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , MicroRNAs/fisiologia , Fator de Necrose Tumoral alfa/genética , Proteínas rho de Ligação ao GTP/genética , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Células Cultivadas , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , MicroRNAs/genética , Proteína de Ligação a GTP rhoC
17.
Science ; 347(6217): 53-6, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25525161

RESUMO

The robust generation of quantum states in the presence of decoherence is a primary challenge for explorations of quantum mechanics at larger scales. Using the mechanical motion of a single trapped ion, we utilize reservoir engineering to generate squeezed, coherent, and displaced-squeezed states as steady states in the presence of noise. We verify the created state by generating two-state correlated spin-motion Rabi oscillations, resulting in high-contrast measurements. For both cooling and measurement, we use spin-oscillator couplings that provide transitions between oscillator states in an engineered Fock state basis. Our approach should facilitate studies of entanglement, quantum computation, and open-system quantum simulations in a wide range of physical systems.

18.
Oral Dis ; 21(2): 207-15, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24724948

RESUMO

OBJECTIVE: Previous studies examining the association between genetic variations in prostaglandin pathway and risk of head and neck cancer (HNC) have only included polymorphisms in the PTGS2 (COX2) gene. This study investigated the association between genetic polymorphisms of six prostaglandin pathway genes (PGDS, PTGDS, PTGES, PTGIS, PTGS1 and PTGS2), and risk of HNC. METHODS: Interviews regarding the consumption of alcohol, betel quid, and cigarette were conducted with 222 HNC cases and 214 controls. Genotyping was performed for 48 tag and functional single-nucleotide polymorphisms (SNPs). RESULTS: Two tag SNPs of PTGIS showed a significant association with HNC risk [rs522962: log-additive odds ratio (OR) = 1.42, 95% confidence interval (CI): 1.01-1.99 and dominant OR = 1.58, 95% CI: 1.02-2.47; rs6125671: log-additive OR = 1.49, 95% CI: 1.08-2.05 and dominant OR = 1.96, 95% CI: 1.16-3.32]. In addition, a region in PTGIS tagged by rs927068 and rs6019902 was significantly associated with risk of HNC (global P = 0.007). Finally, several SNPs interacted with betel quid and cigarette to influence the risk of HNC. CONCLUSIONS: Genetic variations in prostaglandin pathway genes are associated with risk of HNC and may modify the relationship between use of betel quid or cigarette and development of HNC.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Prostaglandinas/biossíntese , Prostaglandinas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Carcinoma de Células Escamosas de Cabeça e Pescoço , Adulto Jovem
19.
Oncogene ; 34(5): 546-57, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24469056

RESUMO

Epithelial-mesenchymal transition (EMT) is an essential step for tumor progression, although the mechanisms driving EMT are still not fully understood. In an effort to investigate these mechanisms, we observed that heregulin (HRG)-mediated activation of HER2, or HER2 overexpression, resulted in EMT, which is accompanied with increased expression of a known EMT regulator Slug, but not TWIST or Snail. We then investigated how HER2 induced Slug expression and found, for the first time, that there are four consensus HSF sequence-binding elements (HSEs), the binding sites for heat shock factor-1 (HSF-1), located in the Slug promoter. HSF-1 bound to and transactivated the Slug promoter independent of heat shock, leading to Slug expression in breast cancer cells. Mutation of the putative HSEs ablated Slug transcriptional activation induced by HRG or HSF-1 overexpression. Knockdown of HSF-1 expression by siRNA reduced Slug expression and HRG-induced EMT. The positive association between HSF-1 and Slug was confirmed by immunohistochemical staining of a cohort of 100 invasive breast carcinoma specimens. While investigating how HER2 activated HSF-1 independent of heat shock, we observed that HER2 activation resulted in concurrent phosphorylation of Akt and HSF-1. We then observed, also for the first time, that Akt directly interacted with HSF-1 and phosphorylated HSF-1 at S326. Inhibition of Akt using siRNA, dominant-negative Akt mutant, or small molecule inhibitors prevented HRG-induced HSF-1 activation and Slug expression. Conversely, constitutively active Akt induced HSF-1 phosphorylation and Slug expression. HSF-1 knockdown reduced the ability of Akt to induce Slug expression, indicating an essential role that HSF-1 plays in Akt-induced Slug upregulation. Altogether, our study uncovered the existence of a novel Akt-HSF-1 signaling axis that leads to Slug upregulation and EMT, and potentially contributes to progression of HER2-positive breast cancer.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/biossíntese , Transição Epitelial-Mesenquimal/genética , Proteína Oncogênica v-akt/metabolismo , Fatores de Transcrição/biossíntese , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição de Choque Térmico , Resposta ao Choque Térmico/genética , Humanos , Células MCF-7 , Neuregulina-1/administração & dosagem , Proteína Oncogênica v-akt/genética , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno , Receptor ErbB-2/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética
20.
Sci Hortic ; 183: 118-129, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32287882

RESUMO

High-temperature and waterlogging are major abiotic stresses that affect the yield and quality of cauliflower. Cauliflower cultivars 'H41' and 'H69' are tolerant to high temperature and flooding, respectively; however, 'H71' is sensitive to both stresses. The objectives of this study were to identify the proteins that were differentially regulated and the physiological changes that occurred during different time periods in 'H41', 'H69', and 'H71' when responding to treatments of flooding, 40 °C, and both stresses combined. Changes in the leaf proteome were analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and identified by Mascot peptide mass fingerprint (PMF) and database searching. Stress treatments caused significant reductions in electrolyte leakage, chlorophyll fluorescence Fv/Fm, chlorophyll content, and water potential as stress times were prolonged. By the comparative proteomic analysis, 85 protein peaks that were differentially expressed in response to combination treatments at 0, 6, and 24 h, 69 (33 in 'H41', 29 in 'H69', and 9 in 'H71') were identified, of which were cultivar specific. Differentially regulated proteins predominantly functioned in photosynthesis and to a lesser extent in energy metabolism, cellular homeostasis, transcription and translation, signal transduction, and protein biosynthesis. This is the first report that utilizes proteomics to discover changes in the protein expression profile of cauliflower in response to heat and flooding.

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