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1.
J Chem Technol Biotechnol ; 97(10): 2706-2719, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37829196

RESUMO

BACKGROUND: The presence of water in organic solvents and biofuels can complicate their production and reuse because many hydrophilic solvents form difficult-to-separate mixtures with water (e.g., azeotropes). Pervaporation (PV) and vapor permeation (V⋅P) remove water from such mixtures via selective solution-diffusion transport through a membrane material. A recent article reviewed design factors that impact the effectiveness of PV/V⋅P solvent dehydration processes (J. Chem. Technol. Biotechnol 95: 495-512 (2020)). For the sake of simplicity, the earlier work assumed constant membrane permeabilities. The objective here is to explore the impact of variable permeabilities on predictions of PV/V⋅P system performance. RESULTS: A multiparameter expression relating permeability to process conditions was incorporated into the spreadsheet calculators from the previous work. Use of the expression was demonstrated with literature ethanol/water PV data for a NaA zeolite material and two poly (vinyl alcohol) (PVA) membranes. The variable permeabilities of the membranes yielded membrane area requirements that were 20-30% different from those calculated using permeances fixed at either end of the target water range. The impact of composition-dependent permeabilities was most pronounced on the fraction of ethanol transferred to the permeate for the NaA membrane. CONCLUSION: The inclusion of membrane permeabilities that vary with fluid composition and temperature noticeably altered predictions of the membrane area required to carry out water removal from ethanol by PV and of the transfer of ethanol to the permeate stream. Unless a PV/V⋅P process is expected to operate at a constant temperature and in a narrow concentration range, process performance estimates would be improved by inclusion of concentration- and temperature-dependent permeabilities or permeances.

2.
Desalination ; 522: 1-14, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37849917

RESUMO

Desalination drinking water systems and industrial processes generating high salinity streams require practical brine management options for disposal and/or treatment. Treatment most often involves large capacity brine concentrating processes, on the order of 2000 m3/day, that rely on water evaporation, vapor compression, and condensation. A new technology adds an aerosol-generating device to the evaporation step with the goal of energy efficient operation even at smaller scales. The principles behind the tornadic flowfield that breaks up and aerosolizes water as air and water flow over the machined surface in the device are introduced. Design of a 6.8 m3/day demonstration system, based on this new technology, producing a NaCl slurry (55 wt% solids) from a 22 wt% NaCl influent is described. Simulations of the system with three influent brine concentrations and three forms of final NaCl concentrate are presented and predicted energy usage is compared to estimates for conventional systems. By varying simulation process parameters, the heat transfer performance of the evaporator/condenser is identified as having a large impact on overall efficiency. The new system is anticipated to be most competitive, on an energy usage basis, with conventional concentrator/crystallizer systems when processing higher salinity brines and producing final concentrates containing precipitated NaCl.

3.
Front Genet ; 12: 714282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34490042

RESUMO

In this study, we investigate the genetic determinants that underlie epilepsy in a captive baboon pedigree and evaluate the potential suitability of this non-human primate model for understanding the genetic etiology of human epilepsy. Archived whole-genome sequence data were analyzed using both a candidate gene approach that targeted variants in baboon homologs of 19 genes (n = 20,881 SNPs) previously implicated in genetic generalized epilepsy (GGE) and a more agnostic approach that examined protein-altering mutations genome-wide as assessed by snpEff (n = 36,169). Measured genotype association tests for baboon cases of epileptic seizure were performed using SOLAR, as well as gene set enrichment analyses (GSEA) and protein-protein interaction (PPI) network construction of top association hits genome-wide (p < 0.01; n = 441 genes). The maximum likelihood estimate of heritability for epileptic seizure in the pedigreed baboon sample is 0.76 (SE = 0.77; p = 0.07). Among candidate genes for GGE, a significant association was detected for an intronic SNP in RBFOX1 (p = 5.92 × 10-6; adjusted p = 0.016). For protein-altering variants, no genome-wide significant results were observed for epilepsy status. However, GSEA revealed significant positive enrichment for genes involved in the extracellular matrix structure (ECM; FDR = 0.0072) and collagen formation (FDR = 0.017), which was reflected in a major PPI network cluster. This preliminary study highlights the potential role of RBFOX1 in the epileptic baboon, a protein involved in transcriptomic regulation of multiple epilepsy candidate genes in humans and itself previously implicated in human epilepsy, both focal and generalized. Moreover, protein-damaging variants from across the genome exhibit a pattern of association that links collagen-containing ECM to epilepsy risk. These findings suggest a shared genetic etiology between baboon and human forms of GGE and lay the foundation for follow-up research.

4.
J Chem Technol Biotechnol ; 95(3): 495-512, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32280154

RESUMO

A recent review article (J Chem Technol Biotechnol 94: 343-365 (2019)) identified several commercially-available permselective materials for drying organic solvents with pervaporation (PV) and vapor permeation (V·P) separation processes. The membrane materials included polymeric and inorganic substances exhibiting a range in the performance characteristics: water permeance, water/solvent selectivity, and maximum use temperature. This paper provides an overview of the factors affecting the design of PV/V·P processes utilizing these membranes to remove water from common organic solvents. Properties of the specific membrane and of the solvent substantially affect the PV/V·P separation. Equally important is the impact of operating parameters on the overall separation. To study these impacts, simplified process performance equations and detailed spreadsheet calculations were developed for single-pass and recirculating batch PV systems and for single-pass V·P systems. Estimates of membrane area, permeate concentration, solvent recovery, permeate condenser temperatures, and heating requirements were calculated. Process variables included: solvent type, water permeance, water/solvent selectivity, initial and final water concentrations, operating temperature (PV) or feed pressure (V·P), temperature drop due to evaporation (PV) or feed-side pressure drop (V·P), and permeate pressure. The target solvents considered were: acetonitrile, 1-butanol, N,N-dimethyl formamide, ethanol, methanol, methyl isobutyl ketone, methyl tert-butyl ether, tetrahydrofuran, acetone, and 2-propanol.

6.
J Econ Entomol ; 113(2): 679-694, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31844898

RESUMO

Addressing the risk from pests present in wood and wood products destined for international trade is an essential step towards minimizing the movement, introduction and establishment of invasive species. One method of managing the pest risk associated with wood commodities is the use of a systems approach that incorporates multiple independent measures applied along a production pathway. However, quantifying the reduction of risk can be difficult because the approach requires raw material infested with the pest of interest at a sufficient density to be able to quantify changes in pest abundance. We tested a systems approach for the production of sawn wood using green ash, Fraxinus pennsylvanica Marshall (Lamiales: Oleaceae), infested with emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), by quantifying the change in pest density during the milling process and the precise effect of heat treatment on insects in situ. Greater than 90% of emerald ash borer were removed at the first step of the milling process (debarking) and >99% were removed before the production of green sawn wood. No insects survived kilning or heat treatment. All life stages of emerald ash borer were killed at 56°C and above. Heat, however, had no sublethal effect on emerald ash borer performance. These results show that the application of a systems approach to mitigate emerald ash borer in heat-treated, sawn wood is effective. Moreover, the model-system approach developed in this study can be a template for investigating the effect of systems approaches for other phloem-feeding insects.


Assuntos
Besouros , Fraxinus , Animais , Comércio , Internacionalidade , Larva , Análise de Sistemas , Madeira
7.
J Chem Technol Biotechnol ; 94(2): 343-365, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930521

RESUMO

Organic solvents are widely used in a variety of industrial sectors. Reclaiming and reusing the solvents may be the most economically and environmentally beneficial option for managing spent solvents. Purifying the solvents to meet reuse specifications can be challenging. For hydrophilic solvents, water must be removed prior to reuse, yet many hydrophilic solvents form hard-to-separate azeotropic mixtures with water. Such mixtures make separation processes energy intensive and cause economic challenges. The membrane processes pervaporation (PV) and vapor permeation (VP) can be less energy intensive than distillation-based processes and have proven to be very effective in removing water from azeotropic mixtures. In PV/VP, separation is based on the solution-diffusion interaction between the dense permselective layer of the membrane and the solvent/water mixture. This review provides a state-of-the-science analysis of materials used as the selective layer(s) of PV/VP membranes in removing water from organic solvents. A variety of membrane materials, such as polymeric, inorganic, mixed matrix, and hybrid, have been reported in the literature. A small subset of these are commercially available and highlighted here: poly(vinyl alcohol), polyimides, amorphous perfluoro polymers, NaA zeolites, chabazite zeolites, T-type zeolites, and hybrid silicas. The typical performance characteristics and operating limits of these membranes are discussed. Solvents targeted by the U.S. Environmental Protection Agency for reclamation are emphasized and ten common solvents are chosen for analysis: acetonitrile, 1-butanol, N,N-dimethyl formamide, ethanol, methanol, methyl isobutyl ketone, methyl tert-butyl ether, tetrahydrofuran, acetone, and 2-propanol.

8.
J Chem Technol Biotechnol ; 92(10): 2506-2518, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29225395

RESUMO

BACKGROUND: When water is recovered from a saline source, a brine concentrate stream is produced. Management of the brine stream can be problematic, particularly in inland regions. An alternative to brine disposal is recovery of water and possibly salts from the concentrate. RESULTS: This review provides an overview of desalination technologies and discusses the thermodynamic efficiencies and operational issues associated with the various technologies particularly with regard to high salinity streams. CONCLUSION: Due to the high osmotic pressures of the brine concentrates, reverse osmosis, the most common desalination technology, is impractical. Mechanical vapor compression which, like reverse osmosis, utilizes mechanical work to operate, is reported to have the highest thermodynamic efficiency of the desalination technologies for treatment of salt-saturated brines. Thermally-driven processes, such as flash evaporation and distillation, are technically able to process saturated salt solutions, but suffer from low thermodynamic efficiencies. This inefficiency could be offset if an inexpensive source of waste or renewable heat could be used. Overarching issues posed by high salinity solutions include corrosion and the formation of scales/precipitates. These issues limit the materials, conditions, and unit operation designs that can be used.

10.
Water Res ; 104: 520-531, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27595700

RESUMO

The need for energy efficient Domestic Wastewater (DWW) treatment is increasing annually with population growth and expanding global energy demand. Anaerobic treatment of low strength DWW produces methane which can be used to as an energy product. Temperature sensitivity, low removal efficiencies (Chemical Oxygen Demand (COD), Suspended Solids (SS), and Nutrients), alkalinity demand, and potential greenhouse gas (GHG) emissions have limited its application to warmer climates. Although well designed anaerobic Membrane Bioreactors (AnMBRs) are able to effectively treat DWW at psychrophilic temperatures (10-30 °C), lower temperatures increase methane solubility leading to increased energy losses in the form of dissolved methane in the effluent. Estimates of dissolved methane losses are typically based on concentrations calculated using Henry's Law but advection limitations can lead to supersaturation of methane between 1.34 and 6.9 times equilibrium concentrations and 11-100% of generated methane being lost in the effluent. In well mixed systems such as AnMBRs which use biogas sparging to control membrane fouling, actual concentrations approach equilibrium values. Non-porous membranes have been used to recover up to 92.6% of dissolved methane and well suited for degassing effluents of Upflow Anaerobic Sludge Blanket (UASB) reactors which have considerable solids and organic contents and can cause pore wetting and clogging in microporous membrane modules. Microporous membranes can recover up to 98.9% of dissolved methane in AnMBR effluents which have low COD and SS concentrations. Sequential Down-flow Hanging Sponge (DHS) reactors have been used to recover between 57 and 88% of dissolved methane from Upflow Anaerobic Sludge Blanket (UASB) reactor effluent at concentrations of greater than 30% and oxidize the rest for a 99% removal of total dissolved methane. They can also remove 90% of suspended solids and COD in UASB effluents and produce a high quality effluent. In situ degassing can increase process stability, COD removal, biomass retention, and headspace methane concentrations. A model for estimating energy consumption associated with membrane-based dissolved methane recovery predicts that recovered dissolved and headspace methane may provide all the energy required for operation of an anaerobic system treating DWW at psychrophilic temperatures.


Assuntos
Metano/química , Águas Residuárias , Anaerobiose , Reatores Biológicos , Esgotos/química , Eliminação de Resíduos Líquidos
11.
Brain Struct Funct ; 221(4): 2023-33, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25749860

RESUMO

The baboon provides a model of photosensitive, generalized epilepsy. This study compares cerebral blood flow responses during intermittent light stimulation (ILS) between photosensitive (PS) and healthy control (CTL) baboons using H 2 (15) O-PET. We examined effective connectivity associated with visual stimulation in both groups using structural equation modeling (SEM). Eight PS and six CTL baboons, matched for age, gender and weight, were classified on the basis of scalp EEG findings performed during the neuroimaging studies. Five H 2 (15) O-PET studies were acquired alternating between resting and activation (ILS at 25 Hz) scans. PET images were acquired in 3D mode and co-registered with MRI. SEM demonstrated differences in neural connectivity between PS and CTL groups during ILS that were not previously identified using traditional activation analyses. First-level pathways consisted of similar posterior-to-anterior projections in both groups. While second-level pathways were mainly lateralized to the left hemisphere in the CTL group, they consisted of bilateral anterior-to-posterior projections in the PS baboons. Third- and fourth-level pathways were only evident in PS baboons. This is the first functional neuroimaging study used to model the photoparoxysmal response (PPR) using a primate model of photosensitive, generalized epilepsy. Evidence of increased interhemispheric connectivity and bidirectional feedback loops in the PS baboons represents electrophysiological synchronization associated with the generation of epileptic discharges. PS baboons demonstrated decreased model stability compared to controls, which may be attributed to greater variability in the driving response or PPRs, or to the influence of regions not included in the model.


Assuntos
Epilepsia Generalizada/fisiopatologia , Epilepsia Reflexa/fisiopatologia , Córtex Visual/fisiologia , Córtex Visual/fisiopatologia , Vias Visuais/fisiologia , Vias Visuais/fisiopatologia , Animais , Córtex Cerebral/fisiologia , Córtex Cerebral/fisiopatologia , Eletroencefalografia , Feminino , Imageamento por Ressonância Magnética , Masculino , Papio anubis , Papio hamadryas , Estimulação Luminosa , Tomografia por Emissão de Pósitrons , Processamento de Sinais Assistido por Computador
12.
J Appl Gerontol ; 34(8): 938-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24652913

RESUMO

This article examines change in the composition of the Texas nursing home population between 1990 and 2009 in relation to the changing prevalence of diabetes. Data from the federal Minimum Data Set for Texas for 1999 and 2009 were analyzed for change in proportion of age groups by the Two-Sample Proportion Test. Change by gender within age groups while controlling for race/ethnicity was analyzed by the Cochran-Mantel-Haenszel test. The percentage of nursing home residents aged 50 to 64 years increased from 8% in 1999 to 12% in 2009, and the change was statistically significant for each race/ethnic group and both genders. The percentage reporting diabetes increased among all groups with more pronounced change for minorities. These results point to a need for closer examination of the impacts of changing diabetes prevalence on nursing homes.


Assuntos
Diabetes Mellitus/epidemiologia , Casas de Saúde , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Grupos Raciais/estatística & dados numéricos , Distribuição por Sexo , Texas/epidemiologia , Adulto Jovem
13.
Comp Med ; 64(2): 135-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24674589

RESUMO

Baboons provide a natural model of epilepsy. However, spontaneous seizures are usually sporadic, brief, and may not be observed. We hypothesized that various types of craniofacial trauma (CFT) may serve as reliable markers for epilepsy. We evaluated the type, demographics, and clinical significance of CFT in a large baboon colony. CFT was categorized according to somatotopic location, propensity to recur, and association with witnessed seizures or abnormal EEG findings. We divided the baboons with CFT into 2 groups: those with known histories of seizures (CFT+Sz, n = 176) and those without seizure histories (CFTonly; n = 515). In CFT+Sz baboons, the 568 injuries identified included periorbital (57%), scalp (27%), muzzle (12%), and facial (4%) injuries; multiple somatotopic locations or body parts were affected in 21 baboons. The most common CFT injuries associated with seizures were periorbital and scalp lesions (43% for each region). Compared with those in CFTonly animals, EEG abnormalities, including interictal epileptic discharges (IED) and photosensitivity were more prevalent in the CFT+Sz group, particularly among baboons with periorbital or scalp injuries. Compared with CFT+Sz animals, CFTonly baboons tended to have later onset and less frequent recurrence of CFT but higher prevalence of muzzle and tooth injuries. IED and photosensitivity were less prevalent in the CFTonly than the CFT+Sz group, with periorbital injuries carrying the highest and muzzle injuries the lowest association with IED or photosensitivity in both groups. Therefore, CFT in general and periorbital injuries in particular may be markers for seizures in baboons.


Assuntos
Animais de Laboratório , Epilepsia/veterinária , Traumatismos Faciais/veterinária , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/patologia , Papio , Crânio/lesões , Animais , Biomarcadores , Eletroencefalografia/veterinária , Epilepsia/complicações , Epilepsia/epidemiologia , Epilepsia/patologia , Traumatismos Faciais/etiologia , Estudos Retrospectivos , Texas/epidemiologia
14.
Epilepsy Res ; 105(1-2): 77-85, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23499213

RESUMO

This is the first large-scale epidemiological study evaluating the prevalence of interictal epileptic discharges (IEDs) and photosensitivity (PS) recorded by scalp EEG in a natural nonhuman-primate model of photosensitive, generalized epilepsy. Scalp EEG was used to characterize electroclinical phenotypes in a large baboon pedigree housed at the Southwest National Primate Research Center at the Texas Biomedical Research Institute (Texas Biomed) based upon IEDs and photosensitivity. Scalp EEG studies including intermittent light stimulation (ILS) were performed in 671 baboons. Clinical histories were available for 531 (79%) of the animals. The EEG studies lasted 53 (±11) min, during which the baboons were lightly sedated with intramuscular ketamine doses of 5.6 (±0.8) mg. The animals were further classified according to electroclinical phenotypes recorded by scalp EEG: presence or absence of IEDs, seizures and photoparoxysmal or photoconvulsive responses. Effects of age, gender, and species on EEG phenotypes were compared using (Chi-square, two-sided, α<0.05). Sensitivity and specificity of IEDs and photosensitivity to detect a history of seizures was calculated. Generalized IEDs and photosensitivity were identified in 324 (49%) and 156 (23%) pedigreed baboons, respectively. Only photosensitivity was associated with gender, significantly increased in males. Otherwise, while IEDs were marginally more prevalent among males, there were no other significant associations of IEDs or photosensitivity with age or subspecies. Photosensitivity was significantly associated with IEDs, with demonstrating a possible association with gender and subspecies. Of 531 baboons with histories of clinical events, 91 (17%) had witnessed seizures and 269 (51%) were asymptomatic. IEDs demonstrated sensitivity and specificity of 62% and 57%, and photosensitivity of 40% and 83%, for prediction of seizures, respectively. While these EEG findings mirror the high prevalence of seizures in the colony, the sensitivity and specificity of scalp EEG may have been affected by ketamine's ability to lower the threshold for IEDs and seizures, particularly in animals predisposed to epilepsy. Photosensitivity provides a specific biological marker for epilepsy in future epidemiological, genetic, behavioral and histopathological studies.


Assuntos
Eletroencefalografia/métodos , Linhagem , Fenótipo , Convulsões/genética , Convulsões/fisiopatologia , Animais , Feminino , Masculino , Papio , Convulsões/diagnóstico
15.
Epilepsy Res ; 101(1-2): 46-55, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22480914

RESUMO

The baboon provides a natural non-human primate model for photosensitive, generalized epilepsy. This study describes an implantation procedure for the placement of subdural grid and strip electrodes for continuous video-EEG monitoring in the epileptic baboon to evaluate the generation and propagation of ictal and interictal epileptic discharges. Subdural grid, strip and depth electrodes were implanted in six baboons, targeting brain regions that were activated in functional neuroimaging studies during photoparoxysmal responses. The baboons were monitored with continuous video-EEG monitoring for 2-21 (mean 9) days. Although the animals were tethered, the EEG signal was transmitted wirelessly to optimize their mobility. Spontaneous seizures, interictal epileptic discharges (IEDs), and responses to intermittent light stimulation (ILS) were assessed. Due to cortical injuries related to the electrode implantation and their displacement, the procedure was modified. Habitual myoclonic and generalized tonic-clonic seizures were recorded in three baboons, all associated with a generalized ictal discharge, but were triggered multiregionally, in the frontal, parietal and occipital cortices. IEDs were similarly expressed multiregionally, and responsible for triggering most generalized spike-and-wave discharges. Generalized photoparoxysmal responses were activated only in one baboon, while driving responses recorded in all three photosensitive baboons were 2.5 times the stimulus rate. In contrast to previous intracranial investigations in this model, generalized ictal and interictal epileptic discharges were triggered by parietal and occipital, in addition to the frontocentral cortices. Furthermore, targeted visual areas responded differently to ILS in photosensitive than nonphotosensitive baboons, but further studies are required before mechanisms can be implicated for ILS-induced activation of the epileptic networks.


Assuntos
Eletroencefalografia/métodos , Epilepsia Generalizada/fisiopatologia , Animais , Encéfalo/patologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Dura-Máter , Estimulação Elétrica , Eletrodos Implantados , Epilepsia Generalizada/patologia , Epilepsia Tônico-Clônica/patologia , Epilepsia Tônico-Clônica/fisiopatologia , Feminino , Inflamação/patologia , Masculino , Monitorização Fisiológica , Papio
16.
J Parasitol ; 98(1): 205-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21830937

RESUMO

We conducted cross-sectional surveys of parasites infecting a large free-living colony of baboons at the Southwest National Primate Research Center in San Antonio in October 2003 and April 2004, immediately before, and 6 mo after, treatment with ivermectin. Trichuris sp. was the predominant species present, infecting 79 and 69% of individual animals in the 2 surveys, with fecal egg counts (FEC) of up to 60,200 eggs per g (epg) (mean = 1,235 in October 2003 and 1,256 in April 2004). Prevalence remained fairly stable across age groups, and intensity was highest in animals <1 or >15 yr old, in contrast to patterns observed in humans, where school-age children show the heaviest infections. Strongyloides sp. was also identified, but the species identity remains uncertain. Small subunit ribosomal DNA sequences differed from published sequences of Strongyloides fuelleborni at multiple sites, but resided in a monophyletic group with other Strongyloides species with 92% bootstrap support. This may reflect a recent acquisition from a local host, or that the published sequence of S. fuelleborni is incorrect. Widespread infections with 2 nematode genera in a free-ranging baboon colony that are an important source of morbidity in human populations provide a useful model system for work on the epidemiology, control, pathology, and genetics of these parasites in a host species that is physiologically, immunologically, and genetically similar to humans.


Assuntos
Doenças dos Macacos/parasitologia , Papio/parasitologia , Estrongiloidíase/veterinária , Tricuríase/veterinária , Distribuição por Idade , Animais , Estudos Transversais , DNA de Helmintos/química , DNA Ribossômico/química , Fezes/parasitologia , Feminino , Masculino , Doenças dos Macacos/epidemiologia , Contagem de Ovos de Parasitas/veterinária , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Alinhamento de Sequência/veterinária , Strongyloides/classificação , Strongyloides/genética , Strongyloides/crescimento & desenvolvimento , Strongyloides/isolamento & purificação , Estrongiloidíase/epidemiologia , Estrongiloidíase/parasitologia , Texas/epidemiologia , Tricuríase/epidemiologia , Tricuríase/parasitologia , Trichuris/crescimento & desenvolvimento , Trichuris/isolamento & purificação
17.
Comp Med ; 62(6): 535-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23561888

RESUMO

This study evaluated the incidence, prevalence, and clinical features of seizures in a pedigreed captive colony of baboons. The association of seizures with subspecies, age, sex, and various clinical features was assessed. Records for 1527 captive, pedigreed baboons were reviewed, and 3389 events were identified in 1098 baboons. Of these events, 1537 (45%) represented witnessed seizures, whereas the remaining 1852 presented with craniofacial trauma or episodic changes in behavior that were suggestive, but not diagnostic, of seizure activity. Seizures were generalized myoclonic or tonic-clonic, with two thirds of the events witnessed in the morning. Seizure onset occurred in adolescence (age, 5 y), with an average of 3 seizures in a lifetime. The incidence and prevalence of seizures were 2.5% and 26%, respectively, whereas the prevalence of recurrent seizures (that is, epilepsy) was 15%. Seizures were more prevalent in male baboons, which tended to present with earlier onset and more seizures over a lifetime than did female baboons. Seizures were equally distributed between the subspecies; age of onset and seizure recurrences did not differ significantly between subspecies. Clinical features including age of onset, characteristics, and diurnal presentation of seizures in baboons suggested similarities to juvenile myoclonic epilepsy in humans. Facial trauma may be useful marker for epilepsy in baboons, but its specificity should be characterized.


Assuntos
Animais de Laboratório , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/patologia , Papio , Convulsões/veterinária , Fatores Etários , Animais , Feminino , Incidência , Masculino , Linhagem , Prevalência , Estudos Retrospectivos , Convulsões/epidemiologia , Convulsões/patologia , Fatores Sexuais
18.
Neuroimage ; 57(4): 1393-401, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21664276

RESUMO

Transcranial magnetic stimulation (TMS) has well-established applications in basic neuroscience and promising applications in neurological and psychiatric disorders. However the underlying mechanisms of TMS-induced alterations in brain function are not well understood. As a result, treatment design parameters are determined ad hoc and not informed by any coherent theory or model. Once the mechanisms underlying TMS's modulatory effects on brain systems are better understood and modeled, TMS's potential as a therapeutic and/or investigative tool will be more readily explored and exploited. An animal model is better suited to study different TMS variables, therefore we developed a baboon model to facilitate testing of some of the current theoretical models of TMS interactions with brain regions. We have demonstrated the feasibility of this approach by successfully imaging cerebral blood flow (CBF) changes with H(2)(15)O positron emission tomography imaging during high-frequency, suprathreshold repetitive TMS in the primary motor cortex of five healthy, adult baboons.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Estimulação Magnética Transcraniana , Animais , Eletroencefalografia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Papio , Tomografia por Emissão de Pósitrons , Processamento de Sinais Assistido por Computador
19.
PLoS One ; 6(3): e18290, 2011 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-21464900

RESUMO

BACKGROUND: The construction of comprehensive reference libraries is essential to foster the development of DNA barcoding as a tool for monitoring biodiversity and detecting invasive species. The looper moths of British Columbia (BC), Canada present a challenging case for species discrimination via DNA barcoding due to their considerable diversity and limited taxonomic maturity. METHODOLOGY/PRINCIPAL FINDINGS: By analyzing specimens held in national and regional natural history collections, we assemble barcode records from representatives of 400 species from BC and surrounding provinces, territories and states. Sequence variation in the barcode region unambiguously discriminates over 93% of these 400 geometrid species. However, a final estimate of resolution success awaits detailed taxonomic analysis of 48 species where patterns of barcode variation suggest cases of cryptic species, unrecognized synonymy as well as young species. CONCLUSIONS/SIGNIFICANCE: A catalog of these taxa meriting further taxonomic investigation is presented as well as the supplemental information needed to facilitate these investigations.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Biblioteca Gênica , Mariposas/classificação , Mariposas/genética , Animais , Sequência de Bases , Colúmbia Britânica , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Especificidade da Espécie
20.
Epilepsy Res ; 93(2-3): 91-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21256716

RESUMO

Brain MRI studies in people with idiopathic generalized epilepsies demonstrate regional morphometric differences, though variable in magnitude and location. As the baboon provides an excellent electroclinical and neuroimaging model for photosensitive generalized epilepsy in humans, this study evaluated MRI volumetric and morphometric differences between baboons with interictal epileptic discharges (IEDs) on scalp EEG and baboons with normal EEG studies. Seventy-seven baboons underwent high-resolution brain MRI and scalp EEG studies. The scans were acquired using an 8-channel primate head coil (Siemens TRIO 3T scanner, Erlangen, Germany). After spatial normalization, sulcal measurements were obtained by object-based-morphology methods. One-hour scalp EEG studies were performed in animals sedated with ketamine. Thirty-eight (22F/16M) baboons had normal EEGs (IED-), while 39 (22F/17M) had generalized IEDs (IED+). The two groups were compared for age, total brain volume, and sulcal areas (Hotelling's Trace) as well as between-subjects comparison of 11 individual sulcal areas (averaged between left and right hemispheres). There were no differences between IED- and IED+ groups with respect to age or total brain (gray or white matter) volume, and multivariate tests demonstrated a marginally significant decrease of sulcal areas in IED+ baboons (p=0.075). Tests of between-subjects effects showed statistically significant decreases in the intraparietal (p=0.002), central (p=0.03) and cingulate sulci (p=0.02), and marginal decreases involving the lunate (p=0.07) and superior temporal sulci (p=0.08). Differences in sulcal areas in IED+ baboons may reflect global developmental abnormalities, while decreases of areas of specific sulci reflect anatomical markers for potential generators or cortical nodes of the networks underlying spontaneous seizures and photosensitivity in the baboon.


Assuntos
Córtex Cerebral/fisiopatologia , Eletroencefalografia , Epilepsia/fisiopatologia , Convulsões/fisiopatologia , Animais , Encéfalo/patologia , Córtex Cerebral/patologia , Interpretação Estatística de Dados , Epilepsia/patologia , Feminino , Lateralidade Funcional/fisiologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Papio , Lobo Parietal/fisiologia , Convulsões/patologia
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