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1.
Am J Otolaryngol ; 45(4): 104334, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38723380

RESUMEN

PURPOSE: Tympanostomy tube (TT) placement is the most frequently performed ambulatory surgery in children under 15. After the procedure it is recommended that patients follow up regularly for "tube checks" until TT extrusion. Such visits incur direct and indirect costs to families in the form of days off from work, copays, and travel expenses. This pilot study aims to compare the efficacy of tympanic membrane (TM) evaluation by an artificial intelligence algorithm with that of clinical staff for determining presence or absence of a tympanostomy tube within the TM. METHODS: Using a digital otoscope, we performed a prospective study in children (ages 10 months-10 years) with a history of TTs who were being seen for follow up in a pediatric otolaryngology clinic. A smartphone otoscope was used by study personnel who were not physicians to take ear exam images, then through conventional otoscopic exam, ears were assessed by a clinician for tubes being in place or tubes having extruded from the TM. We trained and tested a deep learning (artificial intelligence) algorithm to assess the images and compared that with the clinician's assessment. RESULTS: A total of 123 images were obtained from 28 subjects. The algorithm classified images as TM with or without tube in place. Overall classification accuracy was 97.7 %. Recall and precision were 100 % and 96 %, respectively, for TM without a tube present, and 95 % and 100 %, respectively, for TM with a tube in place. DISCUSSION: This is a promising deep learning algorithm for classifying ear tube presence in the TM utilizing images obtained in awake children using an over-the-counter otoscope available to the lay population. We are continuing enrollment, with the goal of building an algorithm to assess tube patency and extrusion.


Asunto(s)
Aprendizaje Profundo , Ventilación del Oído Medio , Humanos , Ventilación del Oído Medio/métodos , Niño , Preescolar , Estudios Prospectivos , Lactante , Proyectos Piloto , Masculino , Femenino , Membrana Timpánica/cirugía , Otoscopía/métodos , Algoritmos , Otoscopios
2.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38385955

RESUMEN

We present the requirements, design, and evaluation of the cryogenic continuously rotating half-wave plate (CHWP) for the Simons Observatory (SO). SO is a cosmic microwave background polarization experiment at Parque Astronómico de Atacama in northern Chile that covers a wide range of angular scales using both small (⌀0.42 m) and large (⌀6 m) aperture telescopes. In particular, the small aperture telescopes (SATs) focus on large angular scales for primordial B-mode polarization. To this end, the SATs employ a CHWP to modulate the polarization of the incident light at 8 Hz, suppressing atmospheric 1/f noise and mitigating systematic uncertainties that would otherwise arise due to the differential response of detectors sensitive to orthogonal polarizations. The CHWP consists of a 505 mm diameter achromatic sapphire HWP and a cryogenic rotation mechanism, both of which are cooled down to ∼50 K to reduce detector thermal loading. Under normal operation, the HWP is suspended by a superconducting magnetic bearing and rotates with a constant 2 Hz frequency, controlled by an electromagnetic synchronous motor. We find that the number of superconductors and the number of magnets that make up the superconducting magnetic bearing are important design parameters, especially for the rotation mechanism's vibration performance. The rotation angle is detected through an angular encoder with a noise level of 0.07 µrad s. During a cooldown process, the rotor is held in place by a grip-and-release mechanism that serves as both an alignment device and a thermal path. In this paper, we provide an overview of the SO SAT CHWP: its requirements, hardware design, and laboratory performance.

3.
Pestic Biochem Physiol ; 182: 105037, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35249647

RESUMEN

New classes of chemistries are needed to control insecticide resistant populations of mosquitoes and prevent transmission of vector-borne diseases (VBDs). Organismal screens of chemical collections have played an important role in the search for new vector insecticides and the identification of active ingredients (AIs) that cause rapid mortality of mosquitoes. Advances in image-based screening offer an opportunity to identify chemistries that operate via novel biochemical modes and investigate the range of phenotypes exhibited by mosquitoes following exposure to lethal and sub-lethal chemical dose. An automated, high throughput phenotypic screen (HTS) employing high-content imaging of first instar (L1) Aedes aegypti larvae was developed to identify chemistries associated with mortality and atypical morphological phenotypes. A pilot screen of the Library of Pharmacologically Active Compounds (LOPAC1280) identified 92 chemistries that disrupted larval activity and development, including conventional insecticides and chemistries known to modulate G protein-coupled receptors (GPCRs) and other molecular targets in mammalian systems. Secondary assay series were used to evaluate a selection of chemistries for impacts on mosquito activity, survival and development. Ritodrine hydrochloride reduced mobility of larvae but had no observable effect on survival and development of mosquitoes. High doses of metergoline suppressed larval activity and sub-lethal dose resulted in pupal mortality. Assay data support the utility of phenotypic screening and diverse entomological end-points for discovery of novel insecticidal chemical scaffolds. The insecticide discovery process must consider how multi-modal efficacy spectra contribute to vector and VBD control.


Asunto(s)
Aedes , Insecticidas , Animales , Insecticidas/química , Insecticidas/toxicidad , Larva , Control de Mosquitos/métodos , Mosquitos Vectores , Fenotipo
4.
Rev Sci Instrum ; 91(12): 124503, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33380005

RESUMEN

We present the design and laboratory evaluation of a cryogenic continuously rotating half-wave plate (CHWP) for the POLARBEAR-2b (PB-2b) cosmic microwave background receiver, the second installment of the Simons Array. PB-2b will observe at 5200 m elevation in the Atacama Desert of Chile in two frequency bands centered at 90 GHz and 150 GHz. In order to suppress atmospheric 1/f noise and mitigate systematic effects that arise when differencing orthogonal detectors, PB-2b modulates linear sky polarization using a CHWP rotating at 2 Hz. The CHWP has a 440 mm clear aperture diameter and is cooled to ≈50 K in the PB-2b receiver cryostat. It consists of a low-friction superconducting magnetic bearing and a low-torque synchronous electromagnetic motor, which together dissipate <2 W. During cooldown, a grip-and-release mechanism centers the rotor to <0.5 mm, and during continuous rotation, an incremental optical encoder measures the rotor angle with a noise level of 0.1 µrad/Hz. We discuss the experimental requirements for the PB-2b CHWP, the designs of its various subsystems, and the results of its evaluation in the laboratory. The presented CHWP has been deployed to Chile and is expected to see first light on PB-2b in 2020 or 2021.

5.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302154

RESUMEN

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

6.
Neuroradiology ; 55(9): 1081-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23740097

RESUMEN

INTRODUCTION: Cervical spine MRI with the neck in extension has been well described over the last 10 years, but its clinical value remains unknown. METHODS: We performed extension imaging in 60 patients in whom the initial neutral study showed borderline cord compression. Images were assessed using a previously validated grading system for cord compression. Multiple linear and area measurements were also obtained. Images were scored blindly and randomly. Inter- and intra-rater variability were determined in a subset of 20 cases. Independent clinical assessment utilised the Ranwat criteria. RESULTS: For most parameters inter/intra-observer variance of kappa/ICC > 0.6 was highly satisfactory. Standard MR was poor at discriminating between patients with and without myelopathy (ROC analysis, area under the curve (AUC), 0.52). This was considerably improved with extension imaging (AUC, 0.60), or by using the change in compression score between neutral and extension studies. Most measurements were not helpful; however, the ratio of cord area/CSF area at the level of maximum compression on extended images was the best discriminator (AUC, 0.71), as well as the presence of T2 change in cord substance (AUC, 0.68). CONCLUSION: This is the first study to demonstrate added clinical value utilising extension MRI. In this cohort of difficult patients, when there was no T2 signal change in the cord, the presence of clinical myelopathy could only be predicted by utilising the data from extension imaging.


Asunto(s)
Algoritmos , Vértebras Cervicales/patología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Cuello/patología , Compresión de la Médula Espinal/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
Regul Toxicol Pharmacol ; 66(1): 72-82, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23523712

RESUMEN

Two US blend style cigarette products, one ventilated, were smoked under 16 smoking regimes. 'Tar', nicotine, carbon monoxide (TNCO) and water smoke yields determined with these regimes, are shown to form part of continuous functions linked with puffing intensity (the product of puff volume and puff frequency) and total puff volume (the product of puff volume and puff number). This allows the prediction of yields for any regime and leads to the conclusion that the characterisation of cigarette products with these analytes is achievable from using a single smoking regime. The rate of increase of TNCO yields decreases as the puffing intensity increases, due to the more rapid burning of the tobacco available for smoking, although (particulate phase) water yield, relative to TNCO, increases considerably with intensity. Total puff volume is linearly related to TNCO machine yields from a range of regimes, to duplicated human yields and to the nicotine and solanesol retained in spent filters. The concentration of these smoke components is essentially independent of the regime used to generate them. This is not the case with water for which the yield in smoke increases exponentially with the total puff volume and its concentration increases rapidly with intensity.


Asunto(s)
Nicotiana/química , Humo/análisis , Fumar/metabolismo , Productos de Tabaco/análisis , Monóxido de Carbono/química , Humanos , Nicotina/química , Breas/química , Agua/química
8.
Zoonoses Public Health ; 59(6): 393-400, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22883515

RESUMEN

Japanese encephalitis was recently reported from individuals in the mountain districts of Nepal without travel history to Japanese encephalitis virus (JEV) endemic areas. We performed a cross-sectional study to estimate the seroprevalence of JEV in pigs and subsequently conducted a survey of farmers to identify risk factors associated with seropositivity. In July and August, 2010, 454 pig serum samples were collected and tested by competitive ELISA. Data from a 35-question survey of 109 pig owners were analysed using multivariate logistic regression. Seventy-six (16.7, 95% CI 13.6-20.4) pigs tested positive for anti-JEV antibodies, none of which had been vaccinated against JEV or sourced from JEV endemic areas. Risk factors associated with JEV seropositivity were 'summer abortion', 'wells as a water source', 'urban location', 'reported presence of mosquitoes' and 'lower elevation'. Our results suggest that JEV is likely circulating in the mountain districts of Nepal, and that locally acquired JEV should be considered a risk for residents and travellers in these areas.


Asunto(s)
Anticuerpos Antivirales/sangre , Culex/virología , Virus de la Encefalitis Japonesa (Especie)/inmunología , Encefalitis Japonesa/epidemiología , Enfermedades de los Porcinos/epidemiología , Animales , Encefalitis Japonesa/inmunología , Encefalitis Japonesa/veterinaria , Encefalitis Japonesa/virología , Femenino , Humanos , Masculino , Nepal/epidemiología , Medición de Riesgo , Factores de Riesgo , Estudios Seroepidemiológicos , Porcinos , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/virología
9.
Br J Radiol ; 85(1016): 1044-51, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22215879

RESUMEN

OBJECTIVES: Standard MRI of the cervical spine is performed in a different anatomical position to that utilised for traditional contrast myelography. Those well practised in myelography are familiar with the considerable changes in configuration of the bony and soft tissues of the cervical spine that may occur with changes in the degree of neck flexion and extension. We set out to compare the findings in a select group of patients with myeloradiculopathy who had undergone myelography and MRI in both standard and neck-extended positions. These findings were correlated with the clinical status. METHODS: 29 patients underwent myelography with CT (CTM) and MRI in neutral and neck-extended positions. The imaging was assessed for the degree of cord compression and neural foraminal narrowing, quantified using a simple grading scheme suitable for routine clinical practice. The degree of neck extension was assessed using an angular measurement. RESULTS: For both CTM and MRI, scanning with the neck extended significantly increases the severity of cord compression compared with the standard supine position, to a degree similar to that shown during conventional prone myelography. The degree of perceived cord compression is related to the degree of neck extension achieved. Correlation of standard MRI findings and the clinical level of radiculopathy is poor. This correlation improves when the neck is extended. CONCLUSIONS: The most appropriate position for routine MRI of the cervical spine in degenerative disease remains unknown, but in selected patients imaging with the neck extended may provide important additional information.


Asunto(s)
Vértebras Cervicales , Imagen por Resonancia Magnética/métodos , Radiculopatía/diagnóstico , Compresión de la Médula Espinal/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mielografía/métodos , Variaciones Dependientes del Observador , Posición Prona , Estudios Retrospectivos , Posición Supina , Tomografía Computarizada por Rayos X
10.
Dev Neurosci ; 34(6): 515-24, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23328535

RESUMEN

Hypoxia-ischemia (HI) and associated brain injuries are seen in premature as well as term infants with birth complications. The resulting impairments involve deficits in many cognitive domains, including language development. Poor rapid auditory processing is hypothesized to be one possible underlying factor leading to subsequent language delays. Mild hypothermia treatment for HI injuries in term infants is widely used as an intervention but can be costly and time consuming. Data suggest that the effectiveness of hypothermia treatment following HI injury declines beyond 6 h following injury. Consequently, the availability of a therapeutic alternative without these limitations could allow doctors to treat HI-injured infants more effectively and thus reduce deleterious cognitive and language outcomes. Evidence from both human studies and animal models of neonatal HI suggests that erythropoietin (Epo), an endogenous cytokine hormone, may be a therapeutic agent that can ameliorate HI brain injury and preserve subsequent cognitive development and function. The current study sought to investigate the therapeutic effectiveness of Epo when administered immediately after HI injury, or delayed at intervals following the injury, in neonatal rodents. Rat pups received an induced HI injury on postnatal day 7, followed by an intraperitoneal injection of Epo (1,000 U/kg) immediately, 60 min, or 180 min following induction of injury. Subjects were tested on rapid auditory processing tasks in juvenile (P38-42) and adult periods (P80-85). Ventricular and cortical size was also measured from post mortem tissue. Results from the current study show a therapeutic benefit of Epo when given immediately following induction of HI injury, with diminished benefit from a 60-min-delayed injection of Epo and no protection following a 180-min-delayed injection. The current data thus show that the effectiveness of a single dose of Epo in ameliorating auditory processing deficits following HI injury decreases precipitously as treatment is delayed following injury. These data may have important implications for experimental human neonatal intervention with Epo.


Asunto(s)
Eritropoyetina/administración & dosificación , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Fármacos Neuroprotectores/administración & dosificación , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Hipoxia-Isquemia Encefálica/patología , Masculino , Ratas , Ratas Wistar
11.
Dev Neurosci ; 33(6): 494-504, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22041713

RESUMEN

Hypoxia-ischemia (HI; concurrent oxygen/blood deficiency) and associated encephalopathy represent a common cause of neurological injury in premature/low-birth-weight infants and term infants with birth complications. Resulting behavioral impairments include cognitive and/or sensory processing deficits, as well as language disabilities, and clinical evidence shows that male infants with HI exhibit more severe cognitive deficits compared to females with equivalent injury. Evidence also demonstrates activation of sex-dependent apoptotic pathways following HI events, with males preferentially activating a caspase-independent cascade of cell death and females preferentially activating a caspase-dependent cascade following neonatal hypoxic and/or ischemic insults. Based on these combined data, the 'female protection' following HI injury may reflect the endogenous X-linked inhibitor of apoptosis (XIAP), which effectively binds effector caspases and halts downstream cleavage of effector caspases (thus reducing cell death). To test this theory, the current study utilized neonatal injections of vehicle or embelin (a small molecule inhibitor of XIAP) in male and female rats with or without induced HI injury on postnatal day 7 (P7). Subsequent behavioral testing using a clinically relevant task revealed that the inhibition of XIAP exacerbated HI-induced persistent behavioral deficits in females, with no effect on HI males. These results support sex differences in mechanisms of cell death following early HI injuries, and suggest a potential clinical benefit from the development of sex-specific neuroprotectants for the treatment of HI.


Asunto(s)
Conducta Animal/fisiología , Hipoxia-Isquemia Encefálica/metabolismo , Caracteres Sexuales , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Animales , Animales Recién Nacidos , Benzoquinonas/farmacología , Femenino , Masculino , Ratas , Ratas Wistar
12.
Int J Dev Neurosci ; 29(6): 621-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21802505

RESUMEN

Hypoxia ischemia (HI; reduced blood oxygenation and/or flow to the brain) represents one of the most common injuries for both term and preterm/very low birth weight (VLBW) infants. These children experience elevated incidence of cognitive and/or sensory processing disabilities, including language based learning disabilities. Clinical data also indicate more substantial long-term deficits for HI injured male babies as compared to HI injured females. Previously, we reported significant deficits in rapid auditory processing and spatial learning in male rats with postnatal day 1 (P1), P7, or P10 HI injury. We also showed sex differences in HI injured animals, with more severe deficits in males as compared to females. Given these findings, combined with extant clinical data, the current study sought to assess a putative role for perinatal testosterone in modulating behavioral outcome following early hypoxic-ischemic injury in rats. Male, female, and testosterone-propionate (TP) treated females were subjected to P7 HI or sham surgery, and subsequently (P30+) underwent a battery of auditory testing and water maze assessment. Results confirm previous reports of sex differences following HI, and add new findings of significantly worse performance in TP-treated HI females compared to vehicle treated HI females. Post mortem anatomic analyses showed consistent effects, with significant brain weight decreases seen in HI male and TP-treated HI females but not female HI or sham groups. Further neuromorphometric analysis of brain structures showed that HI male animals exhibited increased pathology relative to HI females as reflected in ventricular enlargement. Findings suggest that neonatal testosterone may act to enhance the deleterious consequences of early HI brain injury, as measured by both neuropathology and behavior.

13.
Int J Dev Neurosci ; 29(4): 381-8, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21473905

RESUMEN

Hypoxia ischemia (HI; reduced blood oxygenation and/or flow to the brain) represents one of the most common injuries for both term and preterm/very low birth weight (VLBW) infants. These children experience elevated incidence of cognitive and/or sensory processing disabilities, including language based learning disabilities. Clinical data also indicate more substantial long-term deficits for HI injured male babies as compared to HI injured females. Previously, we reported significant deficits in rapid auditory processing and spatial learning in male rats with postnatal day 1 (P1), P7, or P10 HI injury. We also showed sex differences in HI injured animals, with more severe deficits in males as compared to females. Given these findings, combined with extant clinical data, the current study sought to assess a putative role for perinatal testosterone in modulating behavioral outcome following early hypoxic-ischemic injury in rats. Male, female, and testosterone-propionate (TP) treated females were subjected to P7 HI or sham surgery, and subsequently (P30+) underwent a battery of auditory testing and water maze assessment. Results confirm previous reports of sex differences following HI, and add new findings of significantly worse performance in TP-treated HI females compared to vehicle treated HI females. Post mortem anatomic analyses showed consistent effects, with significant brain weight decreases seen in HI male and TP-treated HI females but not female HI or sham groups. Further neuromorphometric analysis of brain structures showed that HI male animals exhibited increased pathology relative to HI females as reflected in ventricular enlargement. Findings suggest that neonatal testosterone may act to enhance the deleterious consequences of early HI brain injury, as measured by both neuropathology and behavior.


Asunto(s)
Animales Recién Nacidos , Conducta Animal/efectos de los fármacos , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/fisiopatología , Caracteres Sexuales , Testosterona/farmacología , Testosterona/uso terapéutico , Animales , Conducta Animal/fisiología , Encéfalo/anatomía & histología , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Femenino , Masculino , Pruebas Neuropsicológicas , Distribución Aleatoria , Ratas , Ratas Wistar
14.
Vet Pathol ; 47(3): 455-61, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20375429

RESUMEN

Sialyl Lewis x-modified core 2 branched O-glycans (C2-O-sLe(x)) on human leukocytes mediate much higher-affinity adhesion to selectins on activated vascular endothelium than does sialyl Lewis x on other structures. In some canine and human carcinomas, high expression of sLe(x)-decorated carbohydrates has been associated with metastasis and, in humans, a poor prognosis, but detection in canine gastric carcinomas is unreported. The authors hypothesized that these carbohydrates are highly expressed in more malignant types of canine gastric carcinomas, they promote metastasis, and they are associated with a poorer prognosis for dogs. The objectives were to determine the presence and importance of C2-O-sLe(x) expression in canine gastric carcinomas. Routine histological sections of 16 canine gastric carcinomas were categorized on the basis of 3 classification schemes: World Health Organization, Lauren, and Goseki. Serial sections were stained with antibodies directed against C2-O-sLe(x) (CHO-131 monoclonal antibody), cytokeratin (Lu-5 monoclonal antibody), and stains to detect neutral and acid mucins (periodic acid-Schiff and alcian blue). Whereas normal gastric mucosal epithelial cells were negative for C2-O-sLe(x), 56% of the tumors examined were positive for C2-O-sLe(x). Importantly, the majority of more poorly differentiated tumor types had more numerous and larger intensely stained areas of C2-O-sLe(x) expression compared with moderate to well-differentiated tumor types. Signet ring-type carcinomas had markedly higher distribution and intensity of periodic acid-Schiff and alcian blue staining than did tubular carcinomas. These findings suggest that C2-O-sLe(x) is a tumor-associated antigen that may play a role in the invasiveness and metastatic potential of certain types of canine gastric carcinomas.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Carcinoma/veterinaria , Enfermedades de los Perros/inmunología , Oligosacáridos/metabolismo , Neoplasias Gástricas/veterinaria , Animales , Anticuerpos Monoclonales , Carcinoma/inmunología , Perros , Antígeno Sialil Lewis X , Neoplasias Gástricas/inmunología , Regulación hacia Arriba
15.
Am J Med Genet A ; 146A(24): 3173-80, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19012351

RESUMEN

The combination of intracranial calcification and polymicrogyria is usually seen in the context of intrauterine infection, most frequently due to cytomegalovirus. Rare familial occurrences have been reported. We describe five patients-two male-female sibling pairs, one pair born to consanguineous parents, and an unrelated female-with a distinct pattern of band-like intracranial calcification associated with simplified gyration and polymicrogyria. Clinical features include severe post-natal microcephaly, seizures and profound developmental arrest. Testing for infectious agents was negative. We consider that these children have the same recognizable "pseudo-TORCH" phenotype inherited as an autosomal recessive trait.


Asunto(s)
Anomalías Múltiples/patología , Encefalopatías/complicaciones , Calcinosis/complicaciones , Malformaciones del Desarrollo Cortical/complicaciones , Encéfalo/patología , Niño , Resultado Fatal , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Fenotipo , Cambios Post Mortem , Tomografía Computarizada por Rayos X
16.
Int J Parasitol ; 37(12): 1297-305, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17624352

RESUMEN

Ticks and mites (subphylum Chelicerata; subclass Acari) include important pests of animals and plants worldwide. The Ixodes scapularis (black-legged tick) genome sequencing project marks the beginning of the genomics era for the field of acarology. This project is the first to sequence the genome of a blood-feeding tick vector of human disease and a member of the subphylum Chelicerata. Genome projects for other species of Acari are forthcoming and their genome sequences will likely feature significantly in the future of tick research. Parasitologists interested in advancing the field of tick genomics research will be faced with specific challenges. The development of genetic tools and resources, and the size and repetitive nature of tick genomes are important considerations. Innovative approaches may be required to sequence, assemble, annotate and analyse tick genomes. Overcoming these challenges will enable scientists to investigate the genes and genome organisation of this important group of arthropods and may ultimately lead to new solutions for control of ticks and tick-borne diseases.


Asunto(s)
Genoma de los Insectos/genética , Ixodidae/genética , Análisis de Secuencia de ADN/métodos , Animales , Mapeo Cromosómico , Femenino , Masculino , Filogenia , Enfermedades por Picaduras de Garrapatas/prevención & control
17.
Amino Acids ; 32(2): 225-33, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16868650

RESUMEN

Muscle carnosine synthesis is limited by the availability of beta-alanine. Thirteen male subjects were supplemented with beta-alanine (CarnoSyn) for 4 wks, 8 of these for 10 wks. A biopsy of the vastus lateralis was obtained from 6 of the 8 at 0, 4 and 10 wks. Subjects undertook a cycle capacity test to determine total work done (TWD) at 110% (CCT(110%)) of their maximum power (Wmax). Twelve matched subjects received a placebo. Eleven of these completed the CCT(110%) at 0 and 4 wks, and 8, 10 wks. Muscle biopsies were obtained from 5 of the 8 and one additional subject. Muscle carnosine was significantly increased by +58.8% and +80.1% after 4 and 10 wks beta-alanine supplementation. Carnosine, initially 1.71 times higher in type IIa fibres, increased equally in both type I and IIa fibres. No increase was seen in control subjects. Taurine was unchanged by 10 wks of supplementation. 4 wks beta-alanine supplementation resulted in a significant increase in TWD (+13.0%); with a further +3.2% increase at 10 wks. TWD was unchanged at 4 and 10 wks in the control subjects. The increase in TWD with supplementation followed the increase in muscle carnosine.


Asunto(s)
Carnosina/biosíntesis , Suplementos Dietéticos , Músculo Esquelético/metabolismo , beta-Alanina/administración & dosificación , beta-Alanina/farmacología , Adulto , Biopsia , Carnosina/metabolismo , Esquema de Medicación , Prueba de Esfuerzo , Humanos , Concentración de Iones de Hidrógeno , Masculino , Modelos Biológicos , Músculo Esquelético/efectos de los fármacos , Protones , Taurina/metabolismo , Factores de Tiempo
18.
Amino Acids ; 30(3): 279-89, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16554972

RESUMEN

Beta-alanine in blood-plasma when administered as A) histidine dipeptides (equivalent to 40 mg . kg(-1) bwt of beta-alanine) in chicken broth, or B) 10, C) 20 and D) 40 mg . kg(-1) bwt beta-alanine (CarnoSyn, NAI, USA), peaked at 428 +/- SE 66, 47 +/- 13, 374 +/- 68 and 833 +/- 43 microM. Concentrations regained baseline at 2 h. Carnosine was not detected in plasma with A) although traces of this and anserine were found in urine. Loss of beta-alanine in urine with B) to D) was <5%. Plasma taurine was increased by beta-alanine ingestion but this did not result in any increased loss via urine. Pharmacodynamics were further investigated with 3 x B) per day given for 15 d. Dietary supplementation with I) 3.2 and II) 6.4 g . d(-1) beta-alanine (as multiple doses of 400 or 800 mg) or III) L-carnosine (isomolar to II) for 4 w resulted in significant increases in muscle carnosine estimated at 42.1, 64.2 and 65.8%.


Asunto(s)
Carnosina/metabolismo , Suplementos Dietéticos , Músculo Cuádriceps/metabolismo , beta-Alanina/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Dipéptidos/administración & dosificación , Dipéptidos/farmacocinética , Humanos , Masculino , Taurina/sangre , Taurina/orina , beta-Alanina/administración & dosificación
19.
Am J Med Genet A ; 129A(3): 303-7, 2004 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15326633

RESUMEN

We report on three children from two families with Aicardi-Goutières syndrome. All three had congenital glaucoma. Additionally, neuroimaging demonstrated significant brain stem atrophy in the affected sib-pair. These features have not been previously described in Aicardi-Goutières syndrome and expand the phenotypic spectrum.


Asunto(s)
Anomalías Múltiples/patología , Tronco Encefálico/patología , Glaucoma/patología , Enfermedades Neurodegenerativas/patología , Atrofia , Tronco Encefálico/diagnóstico por imagen , Resultado Fatal , Femenino , Humanos , Lactante , Masculino , Tomografía Computarizada por Rayos X
20.
Med Vet Entomol ; 17(2): 224-7, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12823841

RESUMEN

Currently, no published methods describe the extraction of high molecular weight genomic DNA from ixodid ticks (Acari: Ixodidae) and commonly used methods of extraction are not well adapted for use with members of this family. A method for extraction of minimally degraded genomic DNA from ixodid ticks that can be completed in one or two days is described. The method produces DNA which is of sufficient size (>24 kb) for use in Southern analysis and which is readily digestible by restriction endonucleases. Southern analysis using a cytochrome P450 gene probe, demonstrates the success of our method with genomic DNA extracted from two species of Ixodidae, the lone star tick, Amblyomma americanum (Linnaeus) and the cattle fever tick, Boophilus microplus (Canestrini).


Asunto(s)
ADN/genética , ADN/aislamiento & purificación , Genoma , Ixodidae/genética , Animales , Southern Blotting , Sistema Enzimático del Citocromo P-450/genética
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