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1.
J Fish Biol ; 102(2): 358-372, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36333916

RESUMEN

Despite the use of Terminalia catappa (TC) leaf by traditional fish farmers around the world to improve the health status of cultured fish, there is a paucity of information on comprehensive metabolite profile and the maximum safe dose of the plant. This study aims at profiling the methanol leaf extract of T. catappa, quantifying total phenolic content (TPC) as well as the total flavonoid content (TFC) and evaluating its acute toxicity on blood, plasma biochemical parameters and histopathology of some vital organs in red hybrid tilapia (Oreochromis sp.). The experimental fish were acclimatised for 2 weeks and divided into six groups. Group (1) served as a control group and was administered 0.2 ml,g-1 of phosphate buffer saline (PBS). Groups 2-6 were orally administered T. catappa leaf extracts (0.2 ml.50 g-1 ) in the following sequence; 31.25, 62.5, 125, 250 and 500 mg.kg-1 body weight. The metabolites identified in T. catappa using liquid chromatography-tandem mass electrospray ionisation spectrometry (LC-ESI-MS/MS) revealed the presence of organic acids, hydrolysable tannins, phenolic acids and flavonoids. Phenolic quantification revealed reasonable quantity of phenolic compounds (217.48 µg GAEmg-1 for TPC and 91.90 µg. QCEmg-1 for TFC). Furthermore, there was no significant difference in all the tested doses in terms of blood parameters and plasma biochemical analysis except for the packed cell volume (PCV) at 500 mg.kg-1 when compared to the control. Significant histopathological changes were observed in groups administered with the extract at 125, 250 and 500 mg.kg-1 doses. To a very large extent it is therefore safe to administer the extract at 31.25 and 62.5 mg.kg-1 in tilapia.


Asunto(s)
Cíclidos , Terminalia , Tilapia , Animales , Extractos Vegetales/química , Terminalia/química , Espectrometría de Masas en Tándem
2.
BJOG ; 128(6): 1030-1034, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33249716

RESUMEN

We describe a novel surgical technique in 31 women with histopathologically confirmed placenta accreta spectrum (PAS) disorders managed by a multidisciplinary team using a prophylactic infrarenal abdominal aortic cross-clamping technique during caesarean hysterectomy. We conclude that this new surgical procedure is a relatively safe technique to potentially control operative blood loss. Our work may stimulate others to develop protocols assessing this innovative technique to improve the surgical outcome of PAS disorders.


Asunto(s)
Pérdida de Sangre Quirúrgica/prevención & control , Cesárea/métodos , Hemostasis Quirúrgica/métodos , Histerectomía/métodos , Placenta Accreta , Hemorragia Posparto , Adulto , Aorta Abdominal , Cesárea/efectos adversos , Constricción , Duración de la Terapia , Femenino , Humanos , Histerectomía/efectos adversos , Evaluación de Resultado en la Atención de Salud , Grupo de Atención al Paciente , Placenta Accreta/diagnóstico , Placenta Accreta/cirugía , Hemorragia Posparto/etiología , Hemorragia Posparto/prevención & control , Embarazo , Taiwán , Ultrasonografía Doppler en Color/métodos
3.
Clin Immunol ; 221: 108614, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33153974

RESUMEN

The heterogeneous disease course of COVID-19 is unpredictable, ranging from mild self-limiting symptoms to cytokine storms, acute respiratory distress syndrome (ARDS), multi-organ failure and death. Identification of high-risk cases will enable appropriate intervention and escalation. This study investigates the routine laboratory tests and cytokines implicated in COVID-19 for their potential application as biomarkers of disease severity, respiratory failure and need of higher-level care. From analysis of 203 samples, CRP, IL-6, IL-10 and LDH were most strongly correlated with the WHO ordinal scale of illness severity, the fraction of inspired oxygen delivery, radiological evidence of ARDS and level of respiratory support (p ≤ 0.001). IL-6 levels of ≥3.27 pg/ml provide a sensitivity of 0.87 and specificity of 0.64 for a requirement of ventilation, and a CRP of ≥37 mg/l of 0.91 and 0.66. Reliable stratification of high-risk cases has significant implications on patient triage, resource management and potentially the initiation of novel therapies in severe patients.


Asunto(s)
Proteína C-Reactiva/metabolismo , COVID-19/diagnóstico , Síndrome de Liberación de Citoquinas/diagnóstico , Interleucina-6/sangre , Síndrome de Dificultad Respiratoria/diagnóstico , SARS-CoV-2/patogenicidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , COVID-19/sangre , COVID-19/terapia , COVID-19/virología , Síndrome de Liberación de Citoquinas/sangre , Síndrome de Liberación de Citoquinas/terapia , Síndrome de Liberación de Citoquinas/virología , Femenino , Hospitalización , Humanos , Interleucina-10/sangre , L-Lactato Deshidrogenasa/sangre , Masculino , Persona de Mediana Edad , Respiración Artificial , Síndrome de Dificultad Respiratoria/sangre , Síndrome de Dificultad Respiratoria/terapia , Síndrome de Dificultad Respiratoria/virología , Factores de Riesgo , Índice de Severidad de la Enfermedad
4.
Opt Express ; 28(4): 5629-5638, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32121779

RESUMEN

The temperature-dependent polarized photoluminescence spectra of nonpolar ZnO samples were investigated by 263 nm laser. The degree of polarization (DOP) of m-plane quantum wells changes from 76% at 10 K to 40% at 300 K, which is much higher than that of epilayer. The strong anisotropy was presumably attributed to the enhanced confinement effect of a one-dimension confinement structure formed by the intersection of quantum well and basal stacking fault. The polarization of laser beam also has an influence on the DOP. It is assumed that the luminescence polarization should be affected not only by the in-plane strains but also the microstructural defects, which do modify the electronic band structure.

5.
Phys Rev Lett ; 124(24): 240502, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32639797

RESUMEN

Effective quantum communication between remote quantum nodes requires high fidelity quantum state transfer and remote entanglement generation. Recent experiments have demonstrated that microwave photons, as well as phonons, can be used to couple superconducting qubits, with a fidelity limited primarily by loss in the communication channel [P. Kurpiers et al., Nature (London) 558, 264 (2018)NATUAS0028-083610.1038/s41586-018-0195-y; C. J. Axline et al., Nat. Phys. 14, 705 (2018)NPAHAX1745-247310.1038/s41567-018-0115-y; P. Campagne-Ibarcq et al., Phys. Rev. Lett. 120, 200501 (2018)PRLTAO0031-900710.1103/PhysRevLett.120.200501; N. Leung et al., npj Quantum Inf. 5, 18 (2019)2056-638710.1038/s41534-019-0128-0; Y. P. Zhong et al., Nat. Phys. 15, 741 (2019)NPAHAX1745-247310.1038/s41567-019-0507-7; A. Bienfait et al., Science 364, 368 (2019)SCIEAS0036-807510.1126/science.aaw8415]. Adiabatic protocols can overcome channel loss by transferring quantum states without populating the lossy communication channel. Here, we present a unique superconducting quantum communication system, comprising two superconducting qubits connected by a 0.73 m-long communication channel. Significantly, we can introduce large tunable loss to the channel, allowing exploration of different entanglement protocols in the presence of dissipation. When set for minimum loss in the channel, we demonstrate an adiabatic quantum state transfer protocol that achieves 99% transfer efficiency as well as the deterministic generation of entangled Bell states with a fidelity of 96%, all without populating the intervening communication channel, and competitive with a qubit-resonant mode-qubit relay method. We also explore the performance of the adiabatic protocol in the presence of significant channel loss, and show that the adiabatic protocol protects against loss in the channel, achieving higher state transfer and entanglement fidelities than the relay method.

6.
Soft Matter ; 16(32): 7535-7543, 2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32700708

RESUMEN

We study the responses of fluid-immersed soft hydrogel spheres that are sheared under controlled volume fractions. Slippery, deformable particles along with the density-matched interstitial fluid are sandwiched between two opposing rough cones, allowing studies for a wide range of volume fraction φ both above and below the jamming of granular suspension. We utilize sudden cessations of shearing, accompanied by refraction-matched internal imaging, to supplement the conventional flow-curve measurements. At sufficiently high volume fractions, the settling of particles after the cessations exhibits a continuous yet distinct transition over the change of the shear rate. Such changes back out the qualitative difference in the state of flowing prior to the cessations: the quasi-static yielding of a tightly packed network, as opposed to the rapid sliding of particles mediated by the interstitial fluid whose dynamics depends on the driving rate. In addition, we determine the solid-fluid transition using two independent methods: the extrapolation of stress residues and the estimated yield stress from high values of φ, and the settling of particles upon shear cessations as φ goes across the transition. We also verify the power law on values of characteristic stress with respect to the distance from jamming φ - φc, with an exponent close to 2. These results demonstrate a multitude of relaxation timescales behind the dynamics of soft particles, and raise questions on how we extend the existing paradigms of the flow of a densely packed system when the softness is actively involved.

7.
Phys Rev Lett ; 121(19): 196402, 2018 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-30468619

RESUMEN

Single layers of transition metal dichalcogenides (TMDCs) are excellent candidates for electronic applications beyond the graphene platform; many of them exhibit novel properties including charge density waves (CDWs) and magnetic ordering. CDWs in these single layers are generally a planar projection of the corresponding bulk CDWs because of the quasi-two-dimensional nature of TMDCs; a different CDW symmetry is unexpected. We report herein the successful creation of pristine single-layer VSe_{2}, which shows a (sqrt[7]×sqrt[3]) CDW in contrast to the (4×4) CDW for the layers in bulk VSe_{2}. Angle-resolved photoemission spectroscopy from the single layer shows a sizable (sqrt[7]×sqrt[3]) CDW gap of ∼100 meV at the zone boundary, a 220 K CDW transition temperature twice the bulk value, and no ferromagnetic exchange splitting as predicted by theory. This robust CDW with an exotic broken symmetry as the ground state is explained via a first-principles analysis. The results illustrate a unique CDW phenomenon in the two-dimensional limit.

8.
Lett Appl Microbiol ; 67(1): 22-31, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29696668

RESUMEN

Rhizobial symbiotic plasmids play vital roles in mutualistic symbiosis with legume plants by executing the functions of nodulation and nitrogen fixation. To explore the gene composition and genetic constitution of rhizobial symbiotic plasmids, comparison analyses of 24 rhizobial symbiotic plasmids derived from four rhizobial genera was carried out. Results illustrated that rhizobial symbiotic plasmids had higher proportion of functional genes participating in amino acid transport and metabolism, replication; recombination and repair; carbohydrate transport and metabolism; energy production and conversion and transcription. Mesorhizobium amorphae CCNWGS0123 symbiotic plasmid - pM0123d had similar gene composition with pR899b and pSNGR234a. All symbiotic plasmids shared 13 orthologous genes, including five nod and eight nif/fix genes which participate in the rhizobia-legume symbiosis process. These plasmids contained nod genes from four ancestors and fix genes from six ancestors. The ancestral type of pM0123d nod genes was similar with that of Rhizobium etli plasmids, while the ancestral type of pM0123d fix genes was same as that of pM7653Rb. The phylogenetic trees constructed based on nodCIJ and fixABC displayed different topological structures mainly due to nodCIJ and fixABC ancestral type discordance. The study presents valuable insights into mosaic structures and the evolution of rhizobial symbiotic plasmids. SIGNIFICANCE AND IMPACT OF THE STUDY: This study compared 24 rhizobial symbiotic plasmids that included four genera and 11 species, illuminating the functional gene composition and symbiosis gene ancestor types of symbiotic plasmids from higher taxonomy. It provides valuable insights into mosaic structures and the evolution of symbiotic plasmids.


Asunto(s)
Evolución Molecular , Fabaceae/microbiología , Mesorhizobium/genética , Plásmidos/genética , Rhizobium/genética , Simbiosis/genética , Sistemas de Transporte de Aminoácidos/genética , Metabolismo Energético/genética , Genes Bacterianos/genética , Fijación del Nitrógeno/genética , Filogenia
9.
Nano Lett ; 16(10): 6331-6336, 2016 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-27648493

RESUMEN

Charge density wave (CDW) formation in solids is a critical phenomenon involving the collective reorganization of the electrons and atoms in the system into a wave structure, and it is expected to be sensitive to the geometric constraint of the system at the nanoscale. Here, we study the CDW transition in TiSe2, a quasi-two-dimensional layered material, to determine the effects of quantum confinement and changing dimensions in films ranging from a single layer to multilayers. Of key interest is the characteristic length scale for the transformation from a two-dimensional case to the three-dimensional limit. Angle-resolved photoemission spectroscopy (ARPES) measurements of films with thicknesses up to six layers reveal substantial variations in the energy structure of discrete quantum well states; however, the temperature-dependent band gap renormalization converges at just three layers. The results indicate a layer-dependent mixture of two transition temperatures and a very-short-range CDW interaction within a three-dimensional framework.

10.
J Helminthol ; 91(6): 726-738, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27905270

RESUMEN

Extensive field surveys of rodents were conducted in Cambodia from 2008 to 2014 to study the diversity and ecology of helminth infection in wild rodent populations. Gastrointestinal helminths were isolated from 14 species of rodents (569 individuals) trapped from different habitats (forest, dry land, rain-fed land and human settlements) in four provinces of Cambodia (Krong Preah Sihanouk, Mondolkiri, Pursat and Steung Treng). The average prevalence of parasitic infection was 58.5% (range, 16.0-64.7%), and 19 helminth taxa were identified in total. Trichostrongylid nematodes were the most prevalent (25.8%), followed by Raillietina sp. (14.1%), Gongylonema neoplasticum (10.7%), Syphacia muris (9.8%) and Hymenolepis diminuta (9.6%). Potential rodent-borne zoonotic helminths were also identified, and the risks of helminthiasis were discussed. The status of helminth infection and species diversity in rodents from settlements were significantly lower than in rodents from forest and peri-domesticated habitats, which indicates that habitat alteration might affect helminth infection and diversity in rodent hosts. Generalized linear models revealed that host attributes (host species and maturity) and environmental factors (habitat and geographical location) were explanatory variables for helminth infection in these rodents. Using network analyses, we showed that the oriental house rat, Rattus tanezumi, was the most central host in the rodent-helminth assemblage, based on the number of helminth taxa it shared with other rodent species. Therefore, R. tanezumi could play an important role in rodent-helminth interactions and helminth transmission to other rodent hosts.


Asunto(s)
Tracto Gastrointestinal/parasitología , Helmintiasis Animal/parasitología , Helmintos/aislamiento & purificación , Interacciones Huésped-Parásitos , Enfermedades de los Roedores/parasitología , Roedores/parasitología , Animales , Biota , Cambodia/epidemiología , Helmintiasis Animal/epidemiología , Helmintos/clasificación , Helmintos/genética , Helmintos/fisiología , Ratas , Enfermedades de los Roedores/epidemiología , Roedores/clasificación , Roedores/fisiología
14.
Mol Psychiatry ; 19(2): 235-42, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23229049

RESUMEN

Small molecules that increase the presynaptic function of aminergic cells may provide neuroprotection in Parkinson's disease (PD) as well as treatments for attention deficit hyperactivity disorder (ADHD) and depression. Model genetic organisms such as Drosophila melanogaster may enhance the detection of new drugs via modifier or 'enhancer/suppressor' screens, but this technique has not been applied to processes relevant to psychiatry. To identify new aminergic drugs in vivo, we used a mutation in the Drosophila vesicular monoamine transporter (dVMAT) as a sensitized genetic background and performed a suppressor screen. We fed dVMAT mutant larvae ∼ 1000 known drugs and quantitated rescue (suppression) of an amine-dependent locomotor deficit in the larva. To determine which drugs might specifically potentiate neurotransmitter release, we performed an additional secondary screen for drugs that require presynaptic amine storage to rescue larval locomotion. Using additional larval locomotion and adult fertility assays, we validated that at least one compound previously used clinically as an antineoplastic agent potentiates the presynaptic function of aminergic circuits. We suggest that structurally similar agents might be used to development treatments for PD, depression and ADHD, and that modifier screens in Drosophila provide a new strategy to screen for neuropsychiatric drugs. More generally, our findings demonstrate the power of physiologically based screens for identifying bioactive agents for select neurotransmitter systems.


Asunto(s)
Antiparkinsonianos/farmacología , Drosophila melanogaster , Evaluación Preclínica de Medicamentos/métodos , Proteínas de Transporte Vesicular de Monoaminas/metabolismo , Animales , Animales Modificados Genéticamente , Dacarbazina/farmacología , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Femenino , Fertilidad/efectos de los fármacos , Larva/efectos de los fármacos , Larva/fisiología , Locomoción/efectos de los fármacos , Locomoción/fisiología , Masculino , Mutación , Enfermedad de Parkinson/tratamiento farmacológico , Pergolida/farmacología , Sinapsis/efectos de los fármacos , Proteínas de Transporte Vesicular de Monoaminas/genética
15.
Vox Sang ; 108(2): 169-77, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25469648

RESUMEN

BACKGROUND AND OBJECTIVES: Instituto Clodomiro Picado has developed an immunoglobulin G (IgG) plasma fractionation process combining a polyethylene glycol/phosphate aqueous two-phase system (ATPS), caprylic acid precipitation and anion-exchange membrane chromatography. We evaluated the purity and in vitro thrombogenicity of such IgG, in line with current international requirements. MATERIALS AND METHODS: Contributions of the different production steps to reduce thrombogenicity were assessed at 0·2 l-scale, and then the methodology was scaled-up to a 10 l-scale and final products (n = 3) were analysed. Purity, immunoglobulin composition, and subclass distribution were determined by electrophoretic and immunochemical methods. The in vitro thrombogenic potential was determined by a thrombin generation assay (TGA) using a Technothrombin fluorogenic substrate. Prekallikrein activator (PKA), plasmin, factor Xa, thrombin and thrombin-like activities were assessed using S-2302, S-2251, S-2222, S-2238 and S-2288 chromogenic substrates, respectively, and FXI by an ELISA. RESULTS: The thrombogenicity markers were reduced mostly during the ATPS step and were found to segregate mostly into the discarded liquid upper phase. The caprylic acid precipitation eliminated the residual procoagulant activity. The IgG preparations made from the 10 l-batches contained 100% gamma proteins, low residual IgA and undetectable IgM. The IgG subclass distribution was not substantially affected by the process. TGA and amidolytic activities revealed an undetectable in vitro thrombogenic risk and the absence of proteolytic enzymes in the final product. CONCLUSIONS: Fractionating human plasma by an ATPS combined with caprylic acid and membrane chromatography resulted in an IgG preparation of high purity and free of a detectable in vitro thrombogenic risk.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía/métodos , Inmunoglobulina G/aislamiento & purificación , Plasma/química , Caprilatos/química , Ensayo de Inmunoadsorción Enzimática , Factor XIIa/análisis , Humanos , Inmunoglobulina G/química , Oligopéptidos/química , Trombina/biosíntesis
16.
Orthod Craniofac Res ; 18 Suppl 1: 8-17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25865529

RESUMEN

OBJECTIVES: Investigate the expression and activity of inflammatory markers in response to different magnitudes of orthodontic forces and correlate this response with other molecular and cellular events during orthodontic tooth movement. SETTING AND SAMPLE POPULATION: CTOR Laboratory; 245 Sprague Dawley male rats. METHODS AND MATERIALS: Control, sham, and 5 different experimental groups received different magnitudes of force on the right maxillary first molar using a coil spring. In the sham group, the spring was not activated. Control group did not receive any appliance. At days 1, 3, 7, 14, and 28, the maxillae were collected for RNA and protein analysis, immunohistochemistry, and micro-CT. RESULTS: There was a linear relation between the force and the level of cytokine expression at lower magnitudes of force. Higher magnitudes of force did not increase the expression of cytokines. Activity of CCL2, CCL5, IL-1, TNF-α, RANKL, and number of osteoclasts reached a saturation point in response to higher magnitudes of force, with unchanged rate of tooth movement. CONCLUSION: After a certain magnitude of force, there is a saturation in the biological response, and higher forces do not increase inflammatory markers, osteoclasts, nor the amount of tooth movement. Therefore, higher forces to accelerate the rate of tooth movement are not justified.


Asunto(s)
Citocinas/análisis , Alambres para Ortodoncia , Técnicas de Movimiento Dental/instrumentación , Animales , Fenómenos Biomecánicos , Quimiocina CCL2/análisis , Quimiocina CCL5/análisis , Inmunohistoquímica , Mediadores de Inflamación/análisis , Interleucina-1/análisis , Masculino , Maxilar/inmunología , Maxilar/patología , Diente Molar/inmunología , Diente Molar/patología , Osteoclastos/patología , Proteínas/análisis , Ligando RANK/análisis , ARN/análisis , Ratas , Ratas Sprague-Dawley , Estrés Mecánico , Factor de Necrosis Tumoral alfa/análisis , Microtomografía por Rayos X/métodos
17.
J Obstet Gynaecol ; 35(1): 60-3, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25020211

RESUMEN

The current paper describes the age, period and cohort effects on breast cancer mortality in Taiwan. Female breast cancer mortality data were collected from the Taiwan death registries for 1971-2010. The annual percentage changes, age- standardised mortality rates (ASMR) and age-period-cohort model were calculated. The mortality rates increased with advancing age groups when fixing the period. The percentage change in the breast cancer mortality rate increased from 54.79% at aged 20-44 years, to 149.78% in those aged 45-64 years (between 1971-75 and 2006-10). The mortality rates in the 45-64 age group increased steadily from 1971 to 1975 and 2006-10. The 1951 birth cohorts (actual birth cohort; 1947-55) showed peak mortalities in both the 50-54 and 45-49 age groups. We found that the 1951 birth cohorts had the greatest mortality risk from breast cancer. This might be attributed to the DDT that was used in large amounts to prevent deaths from malaria in Taiwan. However, future researches require DDT data to evaluate the association between breast cancer and DDT use.


Asunto(s)
Neoplasias de la Mama/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/inducido químicamente , Estudios de Cohortes , DDT/toxicidad , Femenino , Humanos , Persona de Mediana Edad , Mortalidad/tendencias , Taiwán/epidemiología , Adulto Joven
18.
Diabetes Obes Metab ; 16(3): 223-30, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23909985

RESUMEN

AIM: To evaluate the efficacy and safety of initial combination therapy of sitagliptin 100 mg/day coadministered with all marketed doses of pioglitazone in patients with type 2 diabetes. METHODS: Patients with A1c ≥7.5 and ≤11.0% were randomized among seven arms that received, once daily, 100 mg sitagliptin alone; 15, 30 or 45 mg pioglitazone alone, or 100 mg sitagliptin plus 15, 30 or 45 mg pioglitazone for 54 weeks. The primary endpoint was change from baseline in A1c at week 24. Protocol-specified analyses compared combination therapies with monotherapies at respective dose-strengths and combination of sitagliptin plus pioglitazone 30 mg with pioglitazone 45 mg monotherapy. Post-hoc analyses compared sitagliptin plus pioglitazone 15 mg with pioglitazone monotherapy at the two higher doses. RESULTS: Initial combination therapy with sitagliptin and pioglitazone provided significantly greater reductions in A1c (0.4-0.7% differences) and other glycaemic endpoints than either monotherapy at the same doses. Combining sitagliptin with low-dose pioglitazone generally produced greater glycaemic improvements than higher doses of pioglitazone monotherapy (0.3-0.4% differences in A1c). Combination therapy was generally well tolerated; adverse events (AEs) of hypoglycaemia were reported with similar incidence (7.8-11.1%) in all treatment groups over the 54 weeks of study; oedema was reported in 0.5% of patients in the sitagliptin monotherapy group and 2.7-5.3% among pioglitazone-treated groups. Significant weight gain was observed in all combination-treated groups compared with the sitagliptin monotherapy group. CONCLUSIONS: Initial combination therapy with sitagliptin and pioglitazone provided better glycaemic control than either monotherapy and was generally well tolerated.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/administración & dosificación , Hemoglobina Glucada/efectos de los fármacos , Hipoglucemiantes/administración & dosificación , Pirazinas/administración & dosificación , Tiazolidinedionas/administración & dosificación , Triazoles/administración & dosificación , Adolescente , Adulto , Anciano , Glucemia/metabolismo , Método Doble Ciego , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemia/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Pioglitazona , Fosfato de Sitagliptina , Resultado del Tratamiento
19.
Nano Lett ; 13(11): 5159-64, 2013 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-24079848

RESUMEN

The low-energy quasiparticles in graphene can be described by a Dirac-Weyl Hamiltonian for massless fermions, hence graphene has been proposed to be an effective medium to study exotic phenomena originally predicted for relativistic particle physics, such as Klein tunneling and Zitterbewegung. In this work, we show that another important particle-physics phenomenon, the neutrino oscillation, can be studied and observed in a particular graphene system, namely, twisted bilayer graphene. It has been found that graphene layers grown epitaxially on SiC or by the chemical vapor deposition method on metal substrates display a stacking pattern with adjacent layers rotated by an angle with respect to each other. The quasiparticle states in two distinct graphene layers act as neutrinos with two flavors, and the interlayer interaction between them induces an appreciable coupling between these two "flavors" of massless fermions, leading to neutrino-like oscillations. In addition, our calculation shows that anisotropic transport properties manifest in a specific energy window, which is accessible experimentally in twisted bilayer graphene. Combining two graphene layers enables us to probe the rich physics involving multiple interacting Dirac fermions.

20.
B-ENT ; 10(4): 299-302, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25654954

RESUMEN

OBJECTIVES: To describe an extremely rare pediatric sinonasal schwannoma, and to reviewmanagement strategies and relevant literature. METHODS: Case report of pediatric sinonasal schwannoma, that was imaged with computed tomography and magnetic resonance imaging and managed endoscopically. Immunohistochemical analysis was performed to determine pathology. RESULTS: A 12-year-old girl presented with a 2-month history of progressive left exophthalmos. Imaging studies showed a large heterogeneous tumour arising from the ethmoid sinus and extending to the base of the skull and to the orbital cavity. The lesion was removed with an endonasal radical excision. The final pathological diagnosis was schwannoma. There was no tumour recurrence or any major complication during the 2-year follow up. CONCLUSION: Schwannoma should be considered in the differential diagnosis for pediatric patients with intranasal masses. Depending on the location and extent of the tumour, endonasal endoscopic excision could be a suitable management strategy.


Asunto(s)
Endoscopía/métodos , Senos Etmoidales/cirugía , Neurilemoma/cirugía , Órbita/cirugía , Neoplasias de los Senos Paranasales/cirugía , Base del Cráneo/cirugía , Niño , Senos Etmoidales/diagnóstico por imagen , Senos Etmoidales/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Neurilemoma/diagnóstico por imagen , Neurilemoma/patología , Órbita/diagnóstico por imagen , Neoplasias de los Senos Paranasales/diagnóstico por imagen , Neoplasias de los Senos Paranasales/patología , Base del Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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