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1.
Opt Lett ; 48(3): 582-585, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723536

RESUMEN

We demonstrate a method to emulate the optical performance of silicon photonic devices fabricated using advanced deep-ultraviolet lithography (DUV) processes on a rapid-prototyping electron-beam lithography process. The method is enabled by a computational lithography predictive model generated by processing SEM image data of the DUV lithography process. We experimentally demonstrate the emulation method's accuracy on integrated silicon Bragg grating waveguides and grating-based, add-drop filter devices, two devices that are particularly susceptible to DUV lithography effects. The emulation method allows silicon photonic device and system designers to experimentally observe the effects of DUV lithography on device performance in a low-cost, rapid-prototyping, electron-beam lithography process to enable a first-time-right design flow.

2.
Bioinformatics ; 37(1): 29-35, 2021 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32683444

RESUMEN

MOTIVATION: Many software libraries for using Hidden Markov Models in bioinformatics focus on inference tasks, such as likelihood calculation, parameter-fitting and alignment. However, construction of the state machines can be a laborious task, automation of which would be time-saving and less error-prone. RESULTS: We present Machine Boss, a software tool implementing not just inference and parameter-fitting algorithms, but also a set of operations for manipulating and combining automata. The aim is to make prototyping of bioinformatics HMMs as quick and easy as the construction of regular expressions, with one-line 'recipes' for many common applications. We report data from several illustrative examples involving protein-to-DNA alignment, DNA data storage and nanopore sequence analysis. AVAILABILITY AND IMPLEMENTATION: Machine Boss is released under the BSD-3 open source license and is available from http://machineboss.org/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Biología Computacional , Programas Informáticos , Algoritmos , Almacenamiento y Recuperación de la Información , Análisis de Secuencia
3.
J Anat ; 240(6): 1075-1094, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35048365

RESUMEN

Each rectus extraocular muscle in cetaceans divides into two portions: a massive palpebral belly that inserts into the deep surface of the eyelids and a smaller scleral belly that inserts onto the eyeball. While the cetacean palpebral insertions have long been recognized, their homologies and functions remain unclear. To compare cetacean rectus EOM insertions with the global and orbital rectus EOM insertions of other mammals we dissected orbital contents of 20 odontocete species, 2 mysticete species and 18 non-cetacean species, both aquatic and terrestrial. Four cetacean species were also examined with magnetic resonance imaging (MRI). All four rectus muscles in cetaceans had well-developed palpebral bellies and insertions. Adjacent palpebral bellies showed varying degrees of fusion, from near independence to near complete fusion. Fusion was most complete towards palpebral insertions and less towards origins. A medial moiety of the superior rectus palpebral belly is likely the levator palpebrae superioris. Smaller but still robust scleral insertions were present on all recti, with the medial rectus (MR) being significantly more muscular than the others. All non-cetacean species examined had recti with distinct global and orbital insertions, the latter generally onto Tenon's capsule. Orbital insertions in pygmy hippopotamus and Florida manatee extended into the deep surfaces of the eyelids, hence qualifying as palpebral insertions. Our results suggest that rectus EOMs of mammals generally have both global and orbital insertions, and that palpebral bellies of cetaceans and other species are modified homologs of the orbital insertions. The presence of palpebral insertions in pygmy hippopotamus and absence in other cetartiodactyls suggests an intermediate condition between terrestrial cetartiodactyls and cetaceans. Palpebral insertions in Florida manatee and reports of their presence in some pinnipeds suggest parallel evolution in multiple aquatic lineages. Various functions of cetacean palpebral recti have been proposed, including eyelid dilators, protection during diving and thermogenesis for warming eye and brain. For further insight into their possible functions, we observed eye movements of captive bottlenose dolphins (Tursiops truncatus) at the U.S. National Aquarium. Our observations showed that in addition to rotation of the eyeball the entire surrounding palpebral region also moves during gaze changes. For example during upward gaze the globe not only rotates in supraduction but translates dorsally as well. It appears the rectus palpebral bellies are responsible for flexing the palpebral structures and thus also translating the globe, while the scleral insertions act directly for ocular rotation. Along with frequent non-conjugate eye movements, the oculomotor mechanics and repertoire of cetaceans are thus quite distinctive. Summarily, axial displacement within the orbit is a major 'eye movement' in cetaceans, with protrusion and retraction mediated by well-developed circular muscles and retractor bulbi respectively. Torsional eye movements driven by elaborate oblique EOMs are likewise significant. The roles of rectus EOMs for ocular rotation via their scleral insertions, especially the highly muscular MR, are for typical supra/infraductions and nasal/temporal ductions. The palpebral bellies accentuate these ductions by translating the globe and surrounding structures in the same direction.


Asunto(s)
Movimientos Oculares , Músculos Oculomotores , Animales , Cetáceos , Imagen por Resonancia Magnética , Órbita , Esclerótica
4.
Ann Neurol ; 90(6): 913-926, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34590341

RESUMEN

OBJECTIVE: Neurodevelopmental delays and frontal lobe cortical dysmaturation are widespread among children with congenital heart disease (CHD). The subventricular zone (SVZ) is the largest pool of neural stem/progenitor cells in the postnatal brain. Our aim is to determine the effects of cardiopulmonary bypass (CPB) on neurogenesis and cortical maturation in piglets whose SVZ development is similar to human infants. METHODS: Three-week-old piglets (n = 29) were randomly assigned to control (no surgery), mild-CPB (34°C full flow for 60 minutes) and severe-CPB groups (25°C circulatory-arrest for 60 minutes). The SVZ and frontal lobe were analyzed with immunohistochemistry 3 days and 4 weeks postoperatively. MRI of the frontal lobe was used to assess cortical development. RESULTS: SVZ neurogenic activity was reduced up to 4 weeks after both mild and severe CPB-induced insults. CPB also induced decreased migration of young neurons to the frontal lobe, demonstrating that CPB impairs postnatal neurogenesis. MRI 4 weeks after CPB displayed a decrease in gyrification index and cortical volume of the frontal lobe. Cortical fractional anisotropy was increased after severe CPB injury, indicating a prolonged deleterious impact of CPB on cortical maturation. Both CPB-induced insults displayed a significant change in densities of three major inhibitory neurons, suggesting excitatory-inhibitory imbalance in the frontal cortex. In addition, different CPB insults altered different subpopulations of inhibitory neurons. INTERPRETATION: Our results provide novel insights into cellular mechanisms contributing to CHD-induced neurological impairments. Further refinement of CPB hardware and techniques is necessary to improve long-term frontal cortical dysmaturation observed in children with CHD. ANN NEUROL 2021;90:913-926.


Asunto(s)
Puente Cardiopulmonar , Lóbulo Frontal/crecimiento & desarrollo , Ventrículos Laterales/fisiología , Células-Madre Neurales/fisiología , Neurogénesis/fisiología , Animales , Animales Recién Nacidos , Lóbulo Frontal/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuronas/fisiología , Porcinos
5.
J Anat ; 238(4): 917-941, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33131071

RESUMEN

The oblique extraocular muscles (EOMs) were dissected in 19 cetacean species and 10 non-cetacean mammalian species. Both superior oblique (SO) and inferior oblique (IO) muscles in cetaceans are well developed in comparison to out-groups and have unique anatomical features likely related to cetacean orbital configurations, swimming mechanics, and visual behaviors. Cetacean oblique muscles originate at skeletal locations typical for mammals: SO, from a common tendinous cone surrounding the optic nerve and from the medially adjacent bone surface at the orbital apex; IO, from the maxilla adjacent to lacrimal and frontal bones. However, because of the unusual orbital geometry in cetaceans, the paths and relations of SO and IO running toward their insertions onto the temporal ocular sclera are more elaborate than in humans and most other mammals. The proximal part of the SO extends from its origin at the apex along the dorsomedial aspect of the orbital contents to a strong fascial connection proximal to the preorbital process of the frontal bone, likely the cetacean homolog of the typical mammalian trochlea. However, the SO does not turn at this connection but continues onward, still a fleshy cylinder, until turning sharply as it passes through the external circular muscle (ECM) and parts of the palpebral belly of the superior rectus muscle. Upon departing this "functional trochlea" the SO forms a primary scleral insertion and multiple accessory insertions (AIs) onto adjacent EOM tendons and fascial structures. The primary SO scleral insertions are broad and muscular in most cetacean species examined, while in the mysticete minke whale (Balaenoptera acutorostrata) and fin whale (Balaenoptera physalus) the muscular SO bellies transition into broad fibrous tendons of insertion. The IO in cetaceans originates from an elongated fleshy attachment oriented laterally on the maxilla and continues laterally as a tubular belly before turning caudally at a sharp bend where it is constrained by the ECM and parts of the inferior rectus which form a functional trochlea as with the SO. The IO continues to a fleshy primary insertion on the temporal sclera but, as with SO, also has multiple AIs onto adjacent rectus tendons and connective tissue. The multiple IO insertions were particularly well developed in pygmy sperm whale (Kogia breviceps), minke whale and fin whale. AIs of both SO and IO muscles onto multiple structures as seen in cetaceans have been described in humans and domesticated mammals. The AIs of oblique EOMs seen in all these groups, as well as the unique "functional trochleae" of cetacean SO and IO seem likely to function in constraining the lines of action at the primary scleral insertions of the oblique muscles. The gimble-like sling formed by SO and IO in cetaceans suggest that the "primary" actions of the cetacean oblique EOMs are not only to produce ocular counter-rotations during up-down pitch movements of the head during swimming but also to rotate the plane containing the functional origins of the rectus muscles during other gaze changes.


Asunto(s)
Cetáceos/anatomía & histología , Músculos Oculomotores/anatomía & histología , Animales
6.
NMR Biomed ; 34(2): e4451, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33258202

RESUMEN

The study of cerebral metabolites relies heavily on detection methods and sample preparation. Animal experiments in vivo require anesthetic agents that can alter brain metabolism, whereas ex vivo experiments demand appropriate fixation methods to preserve the tissue from rapid postmortem degradation. In this study, the metabolic profiles of mouse hippocampi using proton magnetic resonance spectroscopy (1 H-MRS) were compared in vivo and in situ with or without focused beam microwave irradiation (FBMI) fixation. Ten major brain metabolites, including lactate (Lac), N-acetylaspartate (NAA), total choline (tCho), myo-inositol (mIns), glutamine (Gln), glutamate (Glu), aminobutyric acid (GABA), glutathione (GSH), total creatine (tCr) and taurine (Tau), were analyzed using LCModel. After FBMI fixation, the concentrations of Lac, tCho and mIns were comparable with those obtained in vivo under isoflurane, whereas other metabolites were significantly lower. Except for a decrease in NAA and an increase in Tau, all the other metabolites remained stable over 41 hours in FBMI-fixed brains. Without FBMI, the concentrations of mIns (before 2 hours), tCho and GABA were close to those measured in vivo. However, higher Lac (P < .01) and lower NAA, Gln, Glu, GSH, tCr and Tau were observed (P < .01). NAA, Gln, Glu, GSH, tCr and Tau exhibited good temporal stability for at least 20 hours in the unfixed brain, whereas a linear increase of tCho, mIns and GABA was observed. Possible mechanisms of postmortem degradation are discussed. Our results indicate that a proper fixation method is required for in situ detection depending on the targeted metabolites of specific interests in the brain.


Asunto(s)
Hipocampo/diagnóstico por imagen , Espectroscopía de Resonancia Magnética/métodos , Neuroimagen/métodos , Espectroscopía de Protones por Resonancia Magnética/métodos , Animales , Agua Corporal , Femenino , Hipocampo/metabolismo , Lípidos/análisis , Masculino , Ratones , Ratones Endogámicos C57BL , Microondas , Cambios Post Mortem , Distribución Aleatoria , Fijación del Tejido/métodos
7.
Opt Lett ; 46(15): 3620, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34329239

RESUMEN

This publisher's note contains corrections to Opt. Lett.46, 2738 (2021)OPLEDP0146-959210.1364/OL.423745.

8.
Opt Lett ; 46(11): 2738-2741, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34061101

RESUMEN

We present the designs, theory, and experimental demonstrations of ultra-broadband, optical add-drop filters on the silicon-on-insulator platform, realized using period-chirped contra-directional couplers. Our fabricated devices have ultra-broad 3 dB bandwidths of up to 11 THz (88.1 nm), with flat-top responses at their drop ports. All of our devices were fabricated using a commercial, CMOS-compatible, 193 nm deep-ultraviolet lithography process. By using lithography-prediction models, the measured bandwidths, insertion losses, central wavelengths, and extinction ratios of our devices are all in good agreement with our predicted, simulated results. Such filters are necessary for photonic integrated circuits to operate over multiple optical bands.

9.
Opt Lett ; 44(2): 435-438, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30644919

RESUMEN

It is shown that an apodization profile to realize a specific spectral response for a silicon integrated Bragg grating (IBG) can be amplified/scaled-up greatly by an order of magnitude by introducing phase delays between the two sides of the apodized gratings. This amplification brings about significant improvements in the apodization dynamic range and resolution/precision, thereby facilitating the spectral tailoring of the IBGs. The concept is first exploited in corrugation width-modulated Gaussian-apodized silicon IBGs, and then in phase-modulated silicon IBGs to achieve a five-channel dispersionless square-shaped filter. Significant spectral performance improvements brought by the amplification are demonstrated in both cases.

10.
Opt Lett ; 44(20): 4929-4932, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31613231

RESUMEN

We report on broadband, flat-top, optical add-drop filters using apodized, sub-wavelength grating contradirectional couplers (SWG CDCs) on a silicon-on-insulator platform. In our device, two asymmetric SWG waveguides, having corrugation-apodized Bragg gratings, are used to couple light contradirectionally between the fundamental and next higher-order transverse electric modes of a two-waveguide system. We demonstrate an apodized, SWG CDC that has a flat-top, drop-port response with a 3 dB bandwidth of 32.6 nm, a sidelobe suppression ratio of 19 dB, and a low excess loss of 0.26 dB. We also demonstrate series-cascaded, apodized, SWG CDCs that have square-shaped, drop-port responses with 3 dB bandwidths >30 nm, sidelobe suppressions >50 dB, and low excess losses <0.85 dB.

11.
Pharmacoepidemiol Drug Saf ; 28(10): 1309-1317, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31392844

RESUMEN

PURPOSE: Adverse event (AE) identification in social media (SM) can be performed using various types of natural language processing (NLP) and machine learning (ML). These methods can be categorized by complexity and precision level. Co-occurrence-based ML methods are rather basic, as they identify simultaneous appearance of drugs and clinical events in a single post. In contrast, statistical learning methods involve more complex NLP and identify drugs, events, and associations between them. We aimed to compare the ability of co-occurrence and NLP to identify AEs and signals of disproportionate reporting (SDR) in patient-generated SM. We also examined the performance of lift in SM-based signal detection (SD). METHODS: Our examination was performed in a corpus of SM posts crawled from open online patient forums and communities, using the spontaneously reported VigiBase data as reference data set. RESULTS: We found that co-occurrence and NLP produce AEs, which are 57% and 93% consistent with VigiBase AEs, respectively. Among the SDRs identified both in SM and in VigiBase, up to 55.3% were identified earlier in co-occurrence, and up to 32.1% were identified earlier in NLP-processed SM. Using lift in SM SD provided performance similar to frequentist methods, both in co-occurrence and in NLP-processed AEs. CONCLUSION: Our results indicate that using SM as a data source complementary to traditional pharmacovigilance sources should be considered further. Various levels of SM processing may be considered, depending on the preferred policies and tolerance for false-positive to false-negative balance in routine pharmacovigilance processes.


Asunto(s)
Recolección de Datos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Procesamiento de Lenguaje Natural , Farmacovigilancia , Medios de Comunicación Sociales/estadística & datos numéricos , Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , Conjuntos de Datos como Asunto , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/diagnóstico , Reacciones Falso Negativas , Reacciones Falso Positivas , Estudios de Factibilidad , Estudios Retrospectivos , Sensibilidad y Especificidad
12.
Mycoses ; 62(10): 969-978, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31355956

RESUMEN

This randomised, double-blind, placebo-controlled trial assessed the efficacy, safety and tolerability of voriconazole+anidulafungin (combination) or voriconazole+placebo (monotherapy) for invasive aspergillosis (IA; NCT00531479). We present a post hoc analysis of Korean and non-Korean patients with IA (including baseline positive serum galactomannan [GM]). Immunocompromised patients ≥ 16 years with IA were randomised 1:1, combination or monotherapy, for ≥ 2 weeks' treatment. The primary endpoint was 6- and 12-week all-cause mortality (Korean modified intent-to-treat [mITT] population). Overall, 454 patients enrolled (Koreans: 56 [combination: 28, monotherapy: 28], non-Koreans: 398 [combination: 200, monotherapy: 198]). The mITT population comprised 40 Koreans (combination: 23; monotherapy: 17) and 237 non-Koreans (combination: 112; monotherapy: 125). Week 6 treatment difference in mortality rate between combination and monotherapy was -6.4% in non-Koreans. This reduction was more marked in Koreans (-22.4%). Week 12 difference in all-cause mortality between combination and monotherapy was -17.7% (Koreans) and -20.2% at Week 6 (Koreans; positive baseline GM). Week 6 mortality (Koreans [mITT]; baseline GM >0.5-2.0) was 0/13 (combination) and 2/6 (monotherapy). Serious adverse events were numerically higher for combination than monotherapy (Koreans: 57.1%, 46.4%; non-Koreans: 49.5%, 46.0%). In Koreans, combination therapy was associated with marginally better outcomes than monotherapy and more so than in non-Koreans.


Asunto(s)
Anidulafungina/uso terapéutico , Antifúngicos/uso terapéutico , Neoplasias Hematológicas/complicaciones , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Voriconazol/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anidulafungina/efectos adversos , Antifúngicos/efectos adversos , Pueblo Asiatico , Método Doble Ciego , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Placebos/administración & dosificación , Análisis de Supervivencia , Resultado del Tratamiento , Voriconazol/efectos adversos , Adulto Joven
13.
Biologicals ; 56: 67-83, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30150108

RESUMEN

Sessions included an overview of past cell therapy (CT) conferences sponsored by the International Alliance for Biological Standardization (IABS). The sessions highlighted challenges in the field of human pluripotent stem cells (hPSCs) and also addressed specific points on manufacturing, bioanalytics and comparability, tumorigenicity testing, storage, and shipping. Panel discussions complemented the presentations. The conference concluded that a range of new standardization groups is emerging that could help the field, but ways must be found to ensure that these efforts are coordinated. In addition, there are opportunities for regulatory convergence starting with a gap analysis of existing guidelines to determine what might be missing and what issues might be creating divergence. More specific global regulatory guidance, preferably from WHO, would be welcome. IABS and the California Institute for Regenerative Medicine (CIRM) will explore with stakeholders the development of a practical and innovative road map to support early CT product (CTP) developers.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Células Madre Pluripotentes , Pruebas de Carcinogenicidad , Guías como Asunto , Humanos , Control de Calidad , Medicina Regenerativa
14.
J Ultrasound Med ; 37(12): 2777-2784, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29656390

RESUMEN

OBJECTIVES: Ultrasound (US) has become an indispensable skill for emergency physicians. Growth in the use of US in emergency medicine (EM) has been characterized by practice guidelines, education requirements, and the number of EM US practitioners. Our purpose was to further document the growth of EM US by profiling the breadth, depth, and quality of US-related research presented at EM's most prominent annual research conference: the Society for Academic Emergency Medicine Annual Meeting. METHODS: We reviewed published research abstracts from the annual Society for Academic Emergency Medicine conferences from 1999 to 2015. Abstracts related to US were identified and examined for the number of authors and rigor of the research design. Designs were categorized as experimental, quasiexperimental, and nonexperimental. Abstract submissions were analyzed by the average rate of change over time. RESULTS: From 1999 to 2015, we observed a 10.2% increase in the number of accepted abstracts related to US research. This rate compared to a 3.2% average rate of change for all abstracts in general. The number of unique authors engaged in US research increased at a rate of 26.6%. Of the 602 abstracts identified as US related, only 12% could be considered experimental research. CONCLUSIONS: We observed larger increases in the number of US-related research relative to the total number of abstracts presented at a national conference. The number of investigators engaging in this research has also steadily increased. The research design of these studies was found to be primarily quasiexperimental. To improve the quality of EM's use of point-of-care US, more rigorous research with experimental designs is needed.


Asunto(s)
Bibliometría , Servicios Médicos de Urgencia/métodos , Ultrasonografía/métodos , Indización y Redacción de Resúmenes , Humanos , Sociedades Médicas , Universidades
15.
J Med Internet Res ; 20(11): e10466, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30459145

RESUMEN

BACKGROUND: While traditional signal detection methods in pharmacovigilance are based on spontaneous reports, the use of social media is emerging. The potential strength of Web-based data relies on their volume and real-time availability, allowing early detection of signals of disproportionate reporting (SDRs). OBJECTIVE: This study aimed (1) to assess the consistency of SDRs detected from patients' medical forums in France compared with those detected from the traditional reporting systems and (2) to assess the ability of SDRs in identifying earlier than the traditional reporting systems. METHODS: Messages posted on patients' forums between 2005 and 2015 were used. We retained 8 disproportionality definitions. Comparison of SDRs from the forums with SDRs detected in VigiBase was done by describing the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, receiver operating characteristics curve, and the area under the curve (AUC). The time difference in months between the detection dates of SDRs from the forums and VigiBase was provided. RESULTS: The comparison analysis showed that the sensitivity ranged from 29% to 50.6%, the specificity from 86.1% to 95.5%, the PPV from 51.2% to 75.4%, the NPV from 68.5% to 91.6%, and the accuracy from 68% to 87.7%. The AUC reached 0.85 when using the metric empirical Bayes geometric mean. Up to 38% (12/32) of the SDRs were detected earlier in the forums than that in VigiBase. CONCLUSIONS: The specificity, PPV, and NPV were high. The overall performance was good, showing that data from medical forums may be a valuable source for signal detection. In total, up to 38% (12/32) of the SDRs could have been detected earlier, thus, ensuring the increased safety of patients. Further enhancements are needed to investigate the reliability and validation of patients' medical forums worldwide, the extension of this analysis to all possible drugs or at least to a wider selection of drugs, as well as to further assess performance against established signals.


Asunto(s)
Bases de Datos Factuales , Francia , Humanos , Internet , Farmacovigilancia
16.
Hum Mol Genet ; 23(15): 4043-50, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24626632

RESUMEN

A promoter polymorphism of the osteopontin (OPN) gene (rs28357094) has been associated with multiple inflammatory states, severity of Duchenne muscular dystrophy (DMD) and muscle size in healthy young adults. We sought to define the mechanism of action of the polymorphism, using allele-specific in vitro reporter assays in muscle cells, and a genotype-stratified intervention in healthy controls. In vitro reporter constructs showed the G allele to respond to estrogen treatment, whereas the T allele showed no transcriptional response. Young adult volunteers (n = 187) were enrolled into a baseline study, and subjects with specific rs28357094 genotypes enrolled into an eccentric muscle challenge intervention [n = 3 TT; n = 3 GG/GT (dominant inheritance model)]. Female volunteers carrying the G allele showed significantly greater inflammation and increased muscle volume change as determined by magnetic resonance imaging T1- and T2-weighted images after eccentric challenge, as well as greater decrement in biceps muscle force. Our data suggest a model where the G allele enables enhanced activities of upstream enhancer elements due to loss of Sp1 binding at the polymorphic site. This results in significantly greater expression of the pro-inflammatory OPN cytokine during tissue remodeling in response to challenge in G allele carriers, promoting muscle hypertrophy in normal females, but increased damage in DMD patients.


Asunto(s)
Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Osteopontina/genética , Polimorfismo Genético , Regiones Promotoras Genéticas , Alelos , Línea Celular , Estrógenos/farmacología , Ejercicio Físico , Femenino , Expresión Génica , Genotipo , Humanos , Inflamación/genética , Inflamación/fisiopatología , Contracción Isométrica , Imagen por Resonancia Magnética , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Mioblastos/efectos de los fármacos , Mioblastos/patología , Osteopontina/metabolismo , Transcripción Genética , Adulto Joven
17.
Opt Lett ; 41(13): 3041-4, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27367096

RESUMEN

We report on a compact, broadband, 2×2 adiabatic 3 dB coupler using sub-wavelength gratings (SWGs) for silicon-on-insulator waveguides. In our device, two SWG waveguides that support two transverse electric modes and have tapered waveguide widths were used to achieve an adiabatic mode evolution of the two-waveguide system for broadband 3 dB power splitting. We present results for a SWG adiabatic 3 dB coupler that has an overall coupler length of 50 µm and achieves broadband power splitting over a 130 nm wavelength range with an imbalance of no greater than ±0.3 dB and with low excess losses of less than 0.5 dB.

18.
J Anat ; 227(3): 255-67, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26278930

RESUMEN

The study of inborn genetic errors can lend insight into mechanisms of normal human development and congenital malformations. Here, we present the first detailed comparison of cranial and neuro pathology in two exceedingly rare human individuals with cyclopia and alobar holoprosencephaly (HPE) in the presence and absence of aberrant chromosome 18 (aCh18). The aCh18 fetus contained one normal Ch18 and one with a pseudo-isodicentric duplication of chromosome 18q and partial deletion of 18p from 18p11.31 where the HPE gene, TGIF, resides, to the p terminus. In addition to synophthalmia, the aCh18 cyclopic malformations included a failure of induction of most of the telencephalon - closely approximating anencephaly, unchecked development of brain stem structures, near absence of the sphenoid bone and a malformed neurocranium and viscerocranium that constitute the median face. Although there was complete erasure of the olfactory and superior nasal structures, rudiments of nasal structures derived from the maxillary bone were evident, but with absent pharyngeal structures. The second non-aCh18 cyclopic fetus was initially classified as a true Cyclops, as it appeared to have a proboscis and one median eye with a single iris, but further analysis revealed two eye globes as expected for synophthalmic cyclopia. Furthermore, the proboscis was associated with the medial ethmoid ridge, consistent with an incomplete induction of these nasal structures, even as the nasal septum and paranasal sinuses were apparently developed. An important conclusion of this study is that it is the brain that predicts the overall configuration of the face, due to its influence on the development of surrounding skeletal structures. The present data using a combination of macroscopic, computed tomography (CT) and magnetic resonance imaging (MRI) techniques provide an unparalleled analysis on the extent of the effects of median defects, and insight into normal development and patterning of the brain, face and their skeletal support.


Asunto(s)
Encéfalo/embriología , Aberraciones Cromosómicas , Cromosomas Humanos Par 18 , Cara/embriología , Holoprosencefalia , Cadáver , Edad Gestacional , Holoprosencefalia/embriología , Holoprosencefalia/genética , Humanos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
19.
Artículo en Inglés | MEDLINE | ID: mdl-38776207

RESUMEN

In convolutional neural networks (CNNs), the convolutions are conventionally performed using a square kernel with a fixed N × N receptive field (RF). However, what matters most to the network is the effective receptive field (ERF), which indicates the extent to which input pixels contribute to an output pixel. Inspired by the property that ERFs typically exhibit a Gaussian distribution, we propose a Gaussian Mask convolutional kernel (GMConv). Specifically, GMConv utilizes the Gaussian function to generate a concentric symmetry mask that is placed over the kernel to refine the RF. We analyze the RFs of CNN kernels in different CNN layers and evaluate our approach through extensive experiments on image classification and object detection tasks. Over several tasks and standard base models, our approach compares favorably against the standard convolution. For instance, using GMConv for AlexNet and ResNet-50, the top-1 accuracy on ImageNet classification is boosted by 0.98% and 0.85% , respectively.

20.
Antimicrob Agents Chemother ; 57(11): 5721-6, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23959306

RESUMEN

The Regional Resistance Surveillance program monitored susceptibility rates and developing resistance by geographic region, including 12 Asia-Pacific (APAC) countries. Reference broth microdilution methods for susceptibility/interpretations were applied, processing 5,053 strains. Among Staphylococcus aureus isolates (37% methicillin-resistant S. aureus [MRSA], highest in South Korea [73%]), linezolid (LZD), tigecycline (TIG), and vancomycin were 100% active, but 33 and 34% of strains were levofloxacin (LEV) or macrolide resistant, respectively. Streptococcus pneumoniae was most resistant to ß-lactams and macrolides (45%) but was LZD, LEV, and TIG susceptible (>98%). Extended-spectrum ß-lactamase (ESBL) phenotype rates in Escherichia coli and Klebsiella spp. were 48 and 47%, respectively, and were highest in Taiwan, at 75 to 91%. The best anti-ESBL-phenotype agents were amikacin (81 to 96% susceptible), colistin (COL; >98%), TIG (>98%), and carbapenems (81 to 97%). Pseudomonas aeruginosa showed ≥20% resistance to all drugs except COL (99% susceptible). In conclusion, endemic evolving antimicrobial resistances in APAC nations show compromised roles for many commonly used antimicrobials.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Monitoreo Epidemiológico , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Antibacterianos/clasificación , Asia/epidemiología , Australia/epidemiología , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Klebsiella/efectos de los fármacos , Klebsiella/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Nueva Zelanda/epidemiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/crecimiento & desarrollo
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