RESUMO
Wavefield imaging can be used for measuring the wavefield produced by an ultrasound transducer for medical and industrial applications, or for the detection and monitoring of defects in non-destructive testing. Typical wavefield imaging methods include interferometry/vibrometry, and the use of microphones and hydrophones. These involve scanning, making them time consuming, and microphones have limited resolution. An alternative method presented here uses thermochromic liquid crystal sensors which react to heat generated due to absorption of ultrasonic waves. The result is a colour scale that varies with temperature, with the temperature change dependent on ultrasonic displacement. Measurements of the resonant modes of a flexural ultrasonic transducer were taken between 320 kHz and 6.77 MHz. Temperature maps were obtained from photographs of the TLC sensor using the true-colour image processing method. The obtained temperature change across the transducer face was compared with displacement measurements taken using interferometry, showing excellent agreement in the position of the mode features and good resolution at lower frequencies. Thermal measurements were also taken to directly observe the heating of the transducer cap, showing the effect of the thermal conductivity of the transducer along with confirming the increased heat generated by the ultrasound absorption when a backing layer is used. The sensors show promise for fast transducer characterisation, with further potential applications in structural health monitoring and defect detection.
RESUMO
The meltwater streams of the McMurdo Dry Valleys are hot spots of biological diversity in the climate-sensitive polar desert landscape. Microbial mats, largely comprised of cyanobacteria, dominate the streams which flow for a brief window of time (~10 weeks) over the austral summer. These communities, critical to nutrient and carbon cycling, display previously uncharacterized patterns of rapid destabilization and recovery upon exposure to variable and physiologically detrimental conditions. Here, we characterize changes in biodiversity, transcriptional responses and activity of microbial mats in response to hydrological disturbance over spatiotemporal gradients. While diverse metabolic strategies persist between marginal mats and main channel mats, data collected from 4 time points during the austral summer revealed a homogenization of the mat communities during the mid-season peak meltwater flow, directly influencing the biogeochemical roles of this stream ecosystem. Gene expression pattern analyses identified strong functional sensitivities of nitrogen-fixing marginal mats to changes in hydrological activities. Stress response markers detailed the environmental challenges of each microhabitat and the molecular mechanisms underpinning survival in a polar desert ecosystem at the forefront of climate change. At mid and end points in the flow cycle, mobile genetic elements were upregulated across all mat types indicating high degrees of genome evolvability and transcriptional synchronies. Additionally, we identified novel antifreeze activity in the stream microbial mats indicating the presence of ice-binding proteins (IBPs). Cumulatively, these data provide a new view of active intra-stream diversity, biotic interactions and alterations in ecosystem function over a high-flow hydrological regime.
RESUMO
To study the structure and function of soil organic matter, soil scientists have performed alkali extractions for soil humic acid (HA) and fulvic acid (FA) fractions for more than 200 years. Over the last few decades aquatic scientists have used similar fractions of dissolved organic matter, extracted by resin adsorption followed by alkali desorption. Critics have claimed that alkali-extractable fractions are laboratory artifacts, hence unsuitable for studying natural organic matter structure and function in field conditions. In response, this review first addresses specific conceptual concerns about humic fractions. Then we discuss several case studies in which HA and FA were extracted from soils, waters, and organic materials to address meaningful problems across diverse research settings. Specifically, one case study demonstrated the importance of humic substances for understanding transport and bioavailability of persistent organic pollutants. An understanding of metal binding sites in FA and HA proved essential to accurately model metal ion behavior in soil and water. In landscape-based studies, pesticides were preferentially bound to HA, reducing their mobility. Compost maturity and acceptability of other organic waste for land application were well evaluated by properties of HA extracted from these materials. A young humic fraction helped understand N cycling in paddy rice ( L.) soils, leading to improved rice management. The HA and FA fractions accurately represent natural organic matter across multiple environments, source materials, and research objectives. Studying them can help resolve important scientific and practical issues.
Assuntos
Monitoramento Ambiental , Substâncias Húmicas/análise , Agricultura , Álcalis , Benzopiranos/análise , Água Doce/química , Solo/químicaRESUMO
Vast expanses of Earth's surface are covered by ice, with microorganisms in these systems affecting local and global biogeochemical cycles. We examined microbial assemblages from habitats fed by glacial meltwater within the McMurdo Dry Valleys, Antarctica and on the west Greenland Ice Sheet (GrIS), evaluating potential physicochemical factors explaining trends in community structure. Microbial assemblages present in the different Antarctic dry valley habitats were dominated by Sphingobacteria andFlavobacteria, while Gammaproteobacteria and Sphingobacteria prevailed in west GrIS supraglacial environments. Microbial assemblages clustered by location (Canada Glacier, Cotton Glacier and west GrIS) and were separated by habitat type (i.e. ice, cryoconite holes, supraglacial lakes, sediment and stream water). Community dissimilarities were strongly correlated with dissolved organic matter (DOM) quality. Microbial meltwater assemblages were most closely associated with different protein-like components of the DOM pool. Microbes in environments with mineral particles (i.e. stream sediments and cryoconite holes) were linked to DOM containing more humic-like fluorescence. Our results demonstrate the establishment of distinct microbial communities within ephemeral glacial meltwater habitats, with DOM-microbe interactions playing an integral role in shaping communities on local and polar spatial scales.
Assuntos
Flavobacteriaceae/isolamento & purificação , Gammaproteobacteria/isolamento & purificação , Camada de Gelo/microbiologia , Sphingobacterium/isolamento & purificação , Regiões Antárticas , Biodiversidade , Canadá , DNA Bacteriano/genética , Flavobacteriaceae/classificação , Flavobacteriaceae/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Groenlândia , Lagos/microbiologia , Microbiota/genética , Sphingobacterium/classificação , Sphingobacterium/genética , ÁguaRESUMO
Graphical abstract key: ADHD, attention deficit hyperactivity disorder; ASD, atrial septal defect; DD, developmental delay; EEG, electroencephalogram; Ht, height; ID, intellectual disability; OCD, obsessive-compulsive disorder; OFC, open fontanelle; PDA, patent ductus arteriosis; PFO, patent foramen ovale; VSD, ventricular septal defect; Wt, weight.
Assuntos
Predisposição Genética para Doença , Deficiência Intelectual/genética , Convulsões/genética , Proteínas de Transporte Vesicular/genética , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Humanos , Lactente , Deficiência Intelectual/fisiopatologia , Masculino , Mutação de Sentido Incorreto/genética , Convulsões/fisiopatologia , Sequenciamento do ExomaRESUMO
Intellectual disability (ID) affects about 3% of the population and has a male gender bias. Of at least 700 genes currently linked to ID, more than 100 have been identified on the X chromosome, including KIAA2022. KIAA2022 is located on Xq13.3 and is expressed in the developing brain. The protein product of KIAA2022, Xlinked Intellectual Disability Protein Related to Neurite Extension (XPN), is developmentally regulated and is involved in neuronal migration and cell adhesion. The clinical manifestations of lossoffunction KIAA2022 mutations have been described previously in 15 males, born from unaffected carrier mothers, but few females. Using wholeexome sequencing, we identified a cohort of five unrelated female patients with de novo probably gene damaging variants in KIAA2022 and core phenotypic features of ID, developmental delay, epilepsy refractory to treatment, and impaired language, of similar severity as reported for male counterparts. This study supports KIAA2022 as a novel cause of Xlinked dominant ID, and broadens the phenotype for KIAA2022 mutations.
Assuntos
Epilepsia , Deficiência Intelectual , Mutação com Perda de Função , Proteínas do Tecido Nervoso , Epilepsia/genética , Exoma , Feminino , Genes Ligados ao Cromossomo X , Humanos , Deficiência Intelectual/genética , Mutação , Proteínas do Tecido Nervoso/genética , Malformações do Sistema Nervoso/genética , FenótipoRESUMO
We describe a first-trimester ultrasound examination in which the finding of fetal encephalocele and the cystic appearance of the kidneys raised suspicion of Meckel-Gruber syndrome (MKS). On the basis of sonographic findings, the patient elected termination of pregnancy, and post-termination studies using next-generation sequencing of a gene panel revealed two mutations (one previously described and the other novel) in the gene CC2D2A. Mutations in CC2D2A are known to cause MKS and Joubert syndrome, thus providing molecular confirmation of the clinical suspicion of MKS and opening the possibility for future prenatal diagnosis. This case highlights the ability to detect important anomalies in the first trimester using ultrasound, even in low-risk situations. It also demonstrates the growing role of new sequencing technologies in fetal testing.
Assuntos
Transtornos da Motilidade Ciliar/diagnóstico por imagem , Encefalocele/diagnóstico por imagem , Doenças Renais Policísticas/diagnóstico por imagem , Proteínas/genética , Ultrassonografia Pré-Natal , Adulto , Transtornos da Motilidade Ciliar/genética , Proteínas do Citoesqueleto , Encefalocele/genética , Feminino , Marcadores Genéticos , Humanos , Mutação , Doenças Renais Policísticas/genética , Gravidez , Primeiro Trimestre da Gravidez , Retinose Pigmentar , Análise de Sequência de DNARESUMO
The aim of this study was to examine the efficacy of meloxicam (MEL) as supportive therapy for calves with neonatal calf diarrhea complex. For this double-blind controlled trial, 62 Holstein male calves were purchased at birth and transported to a research facility. At the naturally occurring onset of diarrhea, defined as the first occurrence of a fecal score greater than 2 on a 4-point scale, calves were enrolled in the study. Each calf with diarrhea was randomly assigned to receive a single subcutaneous injection of MEL at a rate of 0.5 mg/kg of BW or an equal volume of placebo (PLA) solution. Milk, starter ration, and water intakes were determined daily for each calf from arrival until 56 d of age. The calves were weighed on arrival and each week thereafter. Time to weaning and weaning weight were recorded for each calf. Crude associations between treatment and each outcome variable were examined using t-tests and Pearson chi-squared tests. Subsequently, multivariable regression models were constructed to examine the impact of MEL therapy on meaningful outcome variables. The primary experimental unit in all analyses was the individual calf. In total, 56 calves presented with clinical signs of diarrhea and were enrolled in the study. Two PLA-treated calves died after being enrolled in the study, and there was no calf mortality among the MEL-treated calves. For calves that developed diarrhea after 10 d of age, MEL-treated calves were more likely to consume their entire daily milk allowance (P < 0.05) as compared with PLA-treated calves. Meloxicam-treated calves began consuming starter ration earlier (P < 0.01) and at a greater rate (P < 0.001), and consumed more water (P < 0.001) compared with PLA-treated animals. Over the study period, calves treated with MEL gained BW at a faster rate (P < 0.01) than calves treated with PLA. There was no difference in weaning weight (P > 0.05), but MEL-treated calves tended to wean earlier (P = 0.11) than PLA-treated calves. These results demonstrate that calves receiving a single injection of MEL at the onset of diarrhea had improved appetite and performance compared with PLA-treated calves. Thus, MEL is an effective supportive therapy for neonatal calf diarrhea complex.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Doenças dos Bovinos/patologia , Diarreia/veterinária , Tiazinas/farmacologia , Tiazóis/farmacologia , Animais , Animais Recém-Nascidos , Anti-Inflamatórios não Esteroides/uso terapêutico , Peso Corporal/fisiologia , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Diarreia/tratamento farmacológico , Diarreia/patologia , Método Duplo-Cego , Ingestão de Alimentos/fisiologia , Masculino , Meloxicam , Análise de Regressão , Tiazinas/uso terapêutico , Tiazóis/uso terapêuticoRESUMO
Dentinogenesis imperfecta (DGI) and dentin dysplasia (DD) are allelic disorders due to mutations in DSPP. Typically, the phenotype breeds true within a family. Recently, two reports showed that 3 different net -1 bp frameshift mutations early in DSPP's repeat domain caused DD, whereas 6 more 3' frameshift mutations were associated with DGI. Here we identify a DD kindred with a novel -1 bp frameshift (c.3141delC) that falls within the portion of the DSPP repeat domain previously associated solely with the DGI phenotype. This new frameshift mutation shows that overlapping DSPP mutations can give rise to either DGI or DD phenotypes. Furthermore, the consistent kindred presentation of the DD or DGI phenotype appears to be dependent on an as-yet-undescribed genetic modifier closely linked to DSPP.
Assuntos
Displasia da Dentina/genética , Dentinogênese Imperfeita/genética , Proteínas da Matriz Extracelular/genética , Mutação da Fase de Leitura/genética , Fosfoproteínas/genética , Sialoglicoproteínas/genética , Regiões 3' não Traduzidas/genética , Sequência de Aminoácidos/genética , Ácido Aspártico/genética , Pareamento de Bases/genética , Cromossomos Humanos Par 4/genética , Éxons/genética , Haplótipos/genética , Heterozigoto , Homozigoto , Humanos , Linhagem , Fenótipo , Regiões Promotoras Genéticas/genética , Sequências Repetitivas de Ácido Nucleico/genética , Análise de Sequência de Proteína , Deleção de Sequência/genética , Serina/genéticaRESUMO
Thirty-one Holstein bull calves were purchased at birth from 3 dairy farms in Eastern Ontario. Each calf was assigned at random to oral treatment with either 5 mg of halofuginone lactate in 10.0 mL of aqueous carrier solution (Halocur, base comprised 10 mg of benzoic acid, 100 mg of lactic acid, and 0.3 mg of tartrazine) or 10 mL of placebo (Halocur base minus the active ingredient, halofuginone lactate) administered 15 to 30 min after morning milk feeding for the first 7 d of life. Intakes of milk, calf starter, and water, and fecal consistency score were recorded daily for 56 d. Calf weights were recorded weekly for 56 d. Fecal samples were taken from all calves at approximately 2, 7, 14, 21, and 28 d of age for isolation of Cryptosporidium parvum oocysts. Logistic and linear regression analyses were used to assess the effect of treatment on the incidence of diarrhea and C. parvum infection status. The odds of C. parvum shedding among calves in the halofuginone lactate-treated group was 70% lower than the odds of shedding among calves in the placebo group. In calves treated with halofuginone lactate, no oocyst shedding occurred until 2 wk of age, whereas 12.5% of calves in the placebo group began shedding oocysts during wk 1. From all ages of placebo-treated calves, 31 of 73 samples (42.5%) were positive for C. parvum, whereas only 15 of 67 samples (22.4%) from all ages of halofuginone lactate-treated calves tested positive. The largest number of C. parvum-positive samples occurred in the third week of life. There was a significant delay of 3.1 d in the incidence of diarrhea among calves treated with halofuginone lactate. Intake of milk and starter, body weight gains, and age at weaning were not significantly different between treatment groups.
Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Doenças dos Bovinos/prevenção & controle , Coccidiostáticos/administração & dosagem , Criptosporidiose/veterinária , Cryptosporidium parvum , Quinazolinas/administração & dosagem , Animais , Bovinos , Coccidiostáticos/efeitos adversos , Criptosporidiose/prevenção & controle , Cryptosporidium parvum/isolamento & purificação , Diarreia/parasitologia , Diarreia/veterinária , Fezes/parasitologia , Masculino , Placebos , Quinazolinas/efeitos adversos , Quinazolinonas , Desmame , Aumento de PesoRESUMO
OBJECTIVES: Intravenous (IV) opioid titration is an accepted method of relieving acute renal colic. Studies have shown that nonsteroidal anti-inflammatory drugs (NSAIDs) are also effective in this setting. Our objective was to compare single-dose ketorolac and titrated meperidine, both administered intravenously, with respect to speed and degree of analgesia, adverse effects and functional status. Our primary hypothesis was that these agents provide equivalent analgesia within 60 minutes. Our secondary hypotheses were that ketorolac-treated patients would experience fewer adverse effects and would be better able to resume usual activity. METHODS: This was a multicentre, double-blind randomized equivalence trial in a convenience sample of patients age 18-65 with moderate or severe renal colic, documented by intravenous pyelogram, ultrasound or stone passage. Meperidine-treated patients received 50 mg IV meperidine at 0 minutes, then 25-50 mg every 15 minutes as needed for ongoing pain. Ketorolac-treated patients received 30 mg IV ketorolac at 0 minutes and placebo injections every 15 minutes as needed. Pain levels and adverse effects were assessed every 15 minutes, and functional status was evaluated at 60 minutes. Our primary outcome was the proportion of patients with mild or no pain at 60 minutes. RESULTS: Overall, 49 of 77 meperidine-treated patients (64%; 95% confidence interval [CI], 53%-75%) and 47 of 65 ketorolac-treated patients (72%; 95% CI, 61%-83%) achieved successful pain relief at 60 minutes (p value for equivalence = 0.002). Ten percent of meperidine-treated patients and 44% of ketorolac-treated patients were able to resume usual activity at 60 minutes (p = 0.001). CONCLUSIONS: In the doses studied, single-dose IV ketorolac is as effective as titrated IV meperidine for the relief of acute renal colic and causes less functional impairment.
RESUMO
Toxicity occurs rapidly after overdose with regular-release valproic acid, but there is less experience with enteric-coated formulations. We report a case of delayed onset of toxicity and time to peak levels after ingestion of enteric-coated divalproex sodium (Epival). The patient was a 24-year-old female who ingested an unknown amount of Epival together with ibuprofen, dimenhydrinate, and ethanol. Ninety minutes after ingestion, the patient had only mild toxicity, and valproic acid was undetectable in her blood. By 13 h post-ingestion, valproate levels were 7450 micromol/L (1,075 mg/L), and the patient was comatose and required endotracheal intubation and mechanical ventilation. The toxicity and pharmacokinetics of valproic acid are discussed in the context of this case, and management guidelines are proposed.
Assuntos
Antimaníacos/intoxicação , Tentativa de Suicídio , Comprimidos com Revestimento Entérico/farmacocinética , Ácido Valproico/intoxicação , Adulto , Antimaníacos/farmacocinética , Disponibilidade Biológica , Overdose de Drogas/terapia , Feminino , Humanos , Diálise Renal , Ácido Valproico/farmacocinéticaRESUMO
The efficiency and accuracy of estrus detection using HeatWatch (DDx Inc., Denver, CO) or visual observation were compared in an autumn-calving Friesian herd (n = 48 per group) and a spring-calving Jersey herd (n = 50 per group) grazing on pasture. Cows in the group monitored by the HeatWatch system were fitted with a pressure-sensitive transmitter that signaled mounting activities associated with estrus. Visual observation was carried out for about 20 min before the morning and afternoon milkings and was aided by a strip of paint applied over the tailhead. Ovarian cyclicity was monitored with progesterone concentrations in milk samples collected twice a week. The efficiency and accuracy of estrus detection were, respectively, 98.4 and 97.6% for visual observation and 91.7 and 100% for HeatWatch detection. Autumn-calving herds differed from spring-calving herds in duration of estrus (9.7 vs. 7.3 h), number of mounts (13.6 vs. 8.5), total duration of mounts (36.8 vs. 19.9 s), and mean duration of a mount (2.6 vs. 2.3 s). There was no significant variation in the distribution of the time of onset of estrus or mounting activities at different hours of the day. Conception rate was similar for AI after estrus detection with HeatWatch (65.8%) or after visual observation (65.0%). The highest conception rate was obtained when AI was carried out between 12 and 18 h after the first mount. Both the HeatWatch system and visual observation plus tail painting can be used for estrus detection of dairy cows on pasture.
Assuntos
Bovinos/fisiologia , Detecção do Estro/métodos , Telemetria/métodos , Animais , Feminino , Inseminação Artificial/veterinária , Leite/química , Pintura , Gravidez , Progesterona/análise , Rádio , Reprodução/fisiologia , Estações do Ano , Comportamento Sexual Animal , Cauda , Fatores de TempoRESUMO
BACKGROUND: Hyperglycemia commonly occurs during cardiopulmonary bypass. We studied the quantitative impact of glucose input and its renal excretion on hyperglycemia during cardiopulmonary bypass. METHODS: The quantity of glucose infused and metabolite and hormone concentrations in plasma, as well as oxygen consumption, carbon dioxide production, and renal glucose excretion, were determined before, during, and after cardiopulmonary bypass in 8 patients. RESULTS: Hyperglycemia (14 to 29 mmol/L) was accompanied by an increase in plasma insulin levels. The degree of hyperglycemia was directly related to the amount of glucose infused. The rate of oxygen consumption did not decrease and the rate of urea appearance (gluconeogenesis) did not rise. Despite a very high filtered load of glucose, there was very little glucosuria, indicating a markedly enhanced renal absorption of glucose. CONCLUSIONS: Hormonal and metabolic factors permit the development of hyperglycemia during cardiopulmonary bypass but its severity depends on the quantity of glucose infused and, what appears to be a new finding, a markedly enhanced renal reabsorption of filtered glucose. Thus the kidney plays an important role in the development of severe hyperglycemia during cardiopulmonary bypass.
Assuntos
Ponte Cardiopulmonar/efeitos adversos , Hiperglicemia/etiologia , Rim/fisiopatologia , Absorção , Glicemia/análise , Temperatura Corporal , Dióxido de Carbono/metabolismo , Ácidos Graxos/sangue , Feminino , Gluconeogênese , Glucose/administração & dosagem , Glucose/metabolismo , Glucose/uso terapêutico , Glicosúria/metabolismo , Hematócrito , Hormônio do Crescimento Humano/sangue , Humanos , Infusões Intravenosas , Insulina/sangue , Rim/metabolismo , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Estudos Prospectivos , Albumina Sérica/análise , Fatores de Tempo , Ureia/urinaRESUMO
A novel integrated assembly process for miniature liquid-crystal-on-silicon displays using photodefinable benzocyclobutene resin is presented. Spin coating speed defines the cell gap, photolithography defines the cell perimeter and spacers, and thermocompression bonding provides the adhesion. The photodefined adhesive spacers provide thin liquid-crystal cell gap control (<2.5 microm) with excellent uniformity (+/-100 nm) for glass-on-glass and glass-on-silicon assemblies. The resin is compatible with common liquid-crystal alignment films and exhibits a bonding shear strength of 22+/-3.2 MPa The assembly process flow and characterization of demonstration devices are described.
RESUMO
BACKGROUND: Oral pharmacotherapy has been commonly used as an adjunct to clean intermittent catheterization (CIC) in the treatment of neurogenic bladder in order to achieve continence, but may be associated with unacceptable side effects. The authors' experience with sterile intravesical preparations of oxybutynin hydrochloride and ephedrine in children is reported here. METHODS: Patients requiring CIC for neurogenic bladder but with incontinence that was unresponsive to standard oral therapy or that was associated with severe systemic side effects were studied over a 1-year period. Clinical, radiological and urodynamic assessments were made prior to commencing treatment with intravesical oxybutynin hydrochloride. Patients who remained incontinent with poor internal sphincter muscle tone had intravesical ephedrine added. RESULTS: Seven patients were involved in the study over a 1-year period. Two patients became continent and one patient had an improvement in upper tract dilatation. One patient had a limited improvement with oxybutynin alone but became continent with the addition of ephedrine. Three patients had no response to treatment. There were few side effects. CONCLUSION: Intravesical agents have a role in the management of paediatric neurogenic bladder for those children with significant adverse sequelae from oral pharmacotherapy who would otherwise require surgical intervention. Intravesical therapy is a safe technique in children with sterile preparations. Further investigation of this modality should be pursued.