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1.
Heliyon ; 10(1): e23269, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163103

RESUMO

Objective: Physician-directed point-of-care ultrasound (PoCUS) is routinely used to identify the etiology of shock and guide therapy in the ICU. We performed a preclinical study to determine what changes are manifested in the femoral vessels during hemorrhagic shock on Duplex imaging and to generate a femoral vessel sonographic profile over the time course of shock. Design & setting: A preclinical study in swine was performed using a convenience sample of animals that were being used in a Trauma Surgery training lab. The animals developed progressive unregulated hemorrhage during the lab. Subjects: Six anesthetized swine underwent Duplex studies of the femoral vessels prior to any hemorrhage and at two time points after the start of hemorrhage. Interventions: N/A. Measurements: Femoral vessel imaging was performed using a portable ultrasound (Sonosite and Clarius). Main results: Femoral arterial peak systolic velocity decreased in all animals with hemorrhage, from a mean (SD) of 77 (27) cm/s pre-hemorrhage to 42 (17) and 32 (16) cm/s at the two post-hemorrhage time points. There were also changes to the arterial waveform morphology. Mean venous velocities also decreased with hemorrhage (20, 11, 7 cm/s). Animals with severe hemorrhage had a cessation of venous flow during positive pressure ventilation. Conclusion: In this preclinical study, both femoral peak systolic velocity and venous velocity decreased with hemorrhage. Femoral vessels represent an easily accessible target for non-invasive hemodynamic monitoring. Changes in femoral vessel Duplex waveforms and velocities should be studied both in a larger sample of animals with controlled hemorrhage and in human trauma patients to determine whether changes appear in early hemorrhage, before the onset of clinically evident hemorrhagic shock.

2.
Ultrasound J ; 15(1): 33, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37530991

RESUMO

BACKGROUND: Measurement of the optic nerve sheath diameter (ONSD) via ultrasonography has been proposed as a non-invasive metric of intracranial pressure that may be employed during in-field patient triage. However, first responders are not typically trained to conduct sonographic exams and/or do not have access to an expensive ultrasound device. Therefore, for successful deployment of ONSD measurement in-field, we believe that first responders must have access to low-cost, portable ultrasound and be assisted by artificial intelligence (AI) systems that can automatically interpret the optic nerve sheath ultrasound scan. We examine the suitability of five commercially available, low-cost, portable ultrasound devices that can be combined with future artificial intelligence algorithms to reduce the training required for and cost of in-field optic nerve sheath diameter measurement. This paper is focused on the quality of the images generated by these low-cost probes. We report results of a clinician preference survey and compare with a lab analysis of three quantitative image quality metrics across devices. We also examine the suitability of the devices in a hypothetical far-forward deployment using operators unskilled in ultrasound, with the assumption of a future onboard AI video interpreter. RESULTS: We find statistically significant differences in clinician ranking of the devices in the following categories: "Image Quality", "Ease of Acquisition", "Software", and "Overall ONSD". We show differences in signal-to-noise ratio, generalized contrast-to-noise ratio, point-spread function across the devices. These differences in image quality result in a statistically significant difference in manual ONSD measurement. Finally, we show that sufficiently wide transducers can capture the optic nerve sheath during blind (no visible B-mode) scans performed by operators unskilled in sonography. CONCLUSIONS: Ultrasound of the optic nerve sheath has the potential to be a convenient, non-invasive, point-of-injury or triage measure for elevated intracranial pressure in cases of traumatic brain injury. When transducer width is sufficient, briefly trained operators may obtain video sequences of the optic nerve sheath without guidance. This data suggest that unskilled operators are able to achieve the images needed for AI interpretation. However, we also show that image quality differences between ultrasound probes may influence manual ONSD measurements.

3.
J Vis Exp ; (198)2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37607087

RESUMO

The goal of this protocol is to develop a standardized method for acquiring images of the optic nerve sheath and measuring the optic nerve sheath diameter (ONSD). Diagnostic ultrasound of the ONSD to detect intracranial hypertension has traditionally faced many problems because of methodologic discrepancies. Due to inconsistencies in the measuring techniques, the potential for ONSD to become a non-invasive bedside monitoring tool for ICP has been hampered. However, establishing a transparent, consistent methodology for measuring the ONSD would support its use as a valid and reliable method of identifying intracranial hypertension. This is important as it has both high sensitivity and specificity in acute care settings. This narrative review describes ONSD POCUS image acquisition, including patient positioning, transducer selection, probe placement, the acquisition sequence, and image optimization. Further, visual aids are provided to assist in real-time during image acquisition. This method should be considered for patients for whom there are concerns regarding intracranial hypertension but who do not have an intracranial monitor in place.


Assuntos
Hipertensão Intracraniana , Sistemas Automatizados de Assistência Junto ao Leito , Humanos , Hipertensão Intracraniana/diagnóstico por imagem , Cuidados Críticos , Ultrassonografia , Nervo Óptico/diagnóstico por imagem
4.
Psychol Health Med ; 27(6): 1296-1310, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33486976

RESUMO

Prior work has shown that primary care patients endorse one or more of the following PA goals, weight maintenance, overall benefits, stress reduction, weight loss, tone/body shape, overall well-being, cardiovascular fitness, and increased energy. Using self-determination theory as a guide, the present study tested whether these eight goals had indirect effects on likelihood of meeting aerobic PA guidelines through internal motivation, external motivation or both. Patients (N = 642; 60.7% female; 44.5% Black; Mage = 50.26 years) were recruited from the waiting room of a primary care clinic to complete a questionnaire. Results showed that PA goals of tone/shape, weight maintenance, and stress reduction had dual, opposing influences on likelihood of meeting aerobic PA guidelines via internal and external motivation. The goal of weight loss had a negative indirect effect on likelihood of meeting guidelines via external motivation. The PA goals of overall health benefits and cardiovascular health had singular, positive indirect effects on PA via internal motivation. Well-being had a direct positive effect on PA and a negative indirect effect via external motivation. Finally, the goal of improved energy had a direct positive effect on likelihood to meet PA guidelines. Implications for clinical practice and theory development are discussed.


Assuntos
Objetivos , Motivação , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autonomia Pessoal , Redução de Peso
6.
Transl Behav Med ; 10(3): 792-800, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31050759

RESUMO

One approach to increasing physical activity (PA) among adults is to develop interventions targeting PA goals that could be implemented in the primary care setting. However, there is little understanding of the types of goals that individuals bring with them into the primary care setting, which is a necessary first step in building interventions. There were three objectives of the study. One was to identify the types of PA goals held by primary care patients. Another was to examine whether there were racial differences among types of PA goals held by primary care patients. A final objective was to examine the relationship between PA goals and PA behaviors (e.g., meet PA guidelines, number of breaks taken from PA routine). Adults (N = 626; Mage = 51.47, SD = 16.32) were recruited from the waiting room of a primary care clinic over a 30-day span to complete a questionnaire on PA and goals. The most commonly endorsed PA goals included, weight maintenance, overall health benefits, weight loss, well-being, body tone and/or shape, stress reduction, cardiovascular health, and energy level. Black patients were more likely than White patients to report weight loss and weight maintenance goals. Weight maintenance, overall health, and stress reduction are the goals for which the greatest percentage of individuals reported meeting aerobic PA guidelines. Finally, number of breaks taken and average length of breaks were similar across type of PA goal. A relatively small number of goals reflected a majority of the goals pursued by participants in this study. Racial differences in adoption of weight loss and weight maintenance goals highlight the need for further investigation into such differences. Finally, future research should consider the role that goal setting plays in PA adherence, paying particular attention to disparate levels of PA across racial groups.


Assuntos
Exercício Físico , Objetivos , Adulto , Humanos , Atividade Motora , Atenção Primária à Saúde , Redução de Peso
7.
G3 (Bethesda) ; 9(10): 3477-3488, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31444297

RESUMO

To understand the genetic basis of complex traits, it is important to be able to efficiently phenotype many genetically distinct individuals. In the nematode Caenorhabditis elegans, individuals have been isolated from diverse populations around the globe and whole-genome sequenced. As a result, hundreds of wild strains with known genome sequences can be used for genome-wide association studies (GWAS). However, phenotypic analysis of these strains can be laborious, particularly for quantitative traits requiring multiple measurements per strain. Starvation resistance is likely a fitness-proximal trait for nematodes, and it is related to metabolic disease risk in humans. However, natural variation in C. elegans starvation resistance has not been systematically characterized, and precise measurement of the trait is time-intensive. Here, we developed a population-selection-and-sequencing-based approach to phenotype starvation resistance in a pool of 96 wild strains. We used restriction site-associated DNA sequencing (RAD-seq) to infer the frequency of each strain among survivors in a mixed culture over time during starvation. We used manual starvation survival assays to validate the trait data, confirming that strains that increased in frequency over time are starvation-resistant relative to strains that decreased in frequency. Further, we found that variation in starvation resistance is significantly associated with variation at a region on chromosome III. Using a near-isogenic line (NIL), we showed the importance of this genomic interval for starvation resistance. This study demonstrates the feasibility of using population selection and sequencing in an animal model for phenotypic analysis of quantitative traits, documents natural variation of starvation resistance in C. elegans, and identifies a genomic region that contributes to such variation.


Assuntos
Adaptação Biológica/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Mapeamento Cromossômico , Cromossomos , Seleção Genética , Inanição , Animais , Estudo de Associação Genômica Ampla , Fenótipo , Característica Quantitativa Herdável
8.
Bioscience ; 68(12): 990-995, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30524133

RESUMO

We develop a transdisciplinary deliberative model that moves beyond traditional scientific collaborations to include nonscientists in designing complexity-oriented research. We use the case of declining honey bee health as an exemplar of complex real-world problems requiring cross-disciplinary intervention. Honey bees are important pollinators of the fruits and vegetables we eat. In recent years, these insects have been dying at alarming rates. To prompt the reorientation of research toward the complex reality in which bees face multiple challenges, we came together as a group, including beekeepers, farmers, and scientists. Over a 2-year period, we deliberated about how to study the problem of honey bee deaths and conducted field experiments with bee colonies. We show trust and authority to be crucial factors shaping such collaborative research, and we offer a model for structuring collaboration that brings scientists and nonscientists together with the key objects and places of their shared concerns across time.

9.
Elife ; 62017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29063832

RESUMO

daf-16/FoxO is required to survive starvation in Caenorhabditis elegans, but how daf-16IFoxO promotes starvation resistance is unclear. We show that daf-16/FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16/FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Fatores de Transcrição Forkhead/metabolismo , Gluconeogênese , Trealose/biossíntese , Animais , Inanição , Estresse Fisiológico , Sobrevida
10.
PLoS Genet ; 11(12): e1005731, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26656736

RESUMO

Nutrient availability has profound influence on development. In the nematode C. elegans, nutrient availability governs post-embryonic development. L1-stage larvae remain in a state of developmental arrest after hatching until they feed. This "L1 arrest" (or "L1 diapause") is associated with increased stress resistance, supporting starvation survival. Loss of the transcription factor daf-16/FOXO, an effector of insulin/IGF signaling, results in arrest-defective and starvation-sensitive phenotypes. We show that daf-16/FOXO regulates L1 arrest cell-nonautonomously, suggesting that insulin/IGF signaling regulates at least one additional signaling pathway. We used mRNA-seq to identify candidate signaling molecules affected by daf-16/FOXO during L1 arrest. dbl-1/TGF-ß, a ligand for the Sma/Mab pathway, daf-12/NHR and daf-36/oxygenase, an upstream component of the daf-12 steroid hormone signaling pathway, were up-regulated during L1 arrest in a daf-16/FOXO mutant. Using genetic epistasis analysis, we show that dbl-1/TGF-ß and daf-12/NHR steroid hormone signaling pathways are required for the daf-16/FOXO arrest-defective phenotype, suggesting that daf-16/FOXO represses dbl-1/TGF-ß, daf-12/NHR and daf-36/oxygenase. The dbl-1/TGF-ß and daf-12/NHR pathways have not previously been shown to affect L1 development, but we found that disruption of these pathways delayed L1 development in fed larvae, consistent with these pathways promoting development in starved daf-16/FOXO mutants. Though the dbl-1/TGF-ß and daf-12/NHR pathways are epistatic to daf-16/FOXO for the arrest-defective phenotype, disruption of these pathways does not suppress starvation sensitivity of daf-16/FOXO mutants. This observation uncouples starvation survival from developmental arrest, indicating that DAF-16/FOXO targets distinct effectors for each phenotype and revealing that inappropriate development during starvation does not cause the early demise of daf-16/FOXO mutants. Overall, this study shows that daf-16/FOXO promotes developmental arrest cell-nonautonomously by repressing pathways that promote larval development.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Desenvolvimento Embrionário/genética , Fatores de Transcrição Forkhead/genética , Insulina/genética , Neuropeptídeos/genética , Receptores Citoplasmáticos e Nucleares/genética , Somatomedinas/genética , Fator de Crescimento Transformador beta/genética , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/biossíntese , Embrião não Mamífero , Fatores de Transcrição Forkhead/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Insulina/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Neuropeptídeos/biossíntese , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores Citoplasmáticos e Nucleares/biossíntese , Transdução de Sinais , Somatomedinas/metabolismo , Inanição , Fator de Crescimento Transformador beta/biossíntese
11.
J Manag Care Spec Pharm ; 21(10): 946-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26402393

RESUMO

BACKGROUND: Obesity is a serious condition affecting more than 35% of adults in the United States. In obese individuals for whom other weight control methods have been ineffective, bariatric surgery is a safe and effective method of weight control. An estimated 150,000 to 160,000 bariatric surgeries are performed in the United States yearly. Iron deficiency anemia is common in patients after bariatric surgery, with incidence rates up to 49%, and may be due to malabsorption of nutrients.  OBJECTIVES: To (a) compare the medical resource utilization (MRU)- both medical care and treatment resources-and associated costs in a sample of commercially insured adult bariatric surgery patients with and without iron deficiency anemia (IDA), and (b) describe anti-anemia treatment patterns in those bariatric surgery patients diagnosed with IDA. METHODS: Using Truven Health MarketScan claims data, bariatric surgery patients were identified by the ICD-9-CM and CPT procedure codes for bariatric surgery and classified by surgery and IDA diagnosis within 2 years of initial surgery. Intravenous (IV) iron treatment was determined by HCPCS codes, prescription oral iron by NDC numbers, and blood transfusions by CPT and ICD-9-CM codes. Clinical, MRU, and economic outcomes for all-cause health services were compared between IDA and non-IDA patients. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression, controlling for demographic and clinical characteristics on outcomes of complications and hospitalization. RESULTS: Of the 24,344 bariatric surgery patients analyzed, 11.6% received an IDA diagnosis 2 years after surgery (average days to diagnosis = 279). Most IDA patients (78.5%) received a test for iron in the post-index period; only 9.1% received IV iron treatment, with iron dextran (3.8%) and iron sucrose (3.4%) being the most common (average days to IV iron treatment = 403 days). Prescription oral iron was found in 4.9% of all IDA patients (average days to oral iron treatment = 476.7). Approximately 9% of IDA patients received a blood transfusion (average days to transfusion = 304.8). For the total sample, the average age was 46 years with a higher percentage of females (83.9% IDA; 78.7% non-IDA). Most clinical characteristics were similar among patients with and without IDA, except heart disease (1.3% IDA vs. 0.8% non-IDA; P = 0.005) and gallbladder disease (0.0% IDA vs. 0.2% non-IDA; P = 0.037). More IDA patients had complications after surgery (40.4% vs. 27.7%; P less than 0.001), such as nonabsorption (22.4% vs. 16.5%; P less than 0.001); digestive (15.6% vs. 10.2%; P less than 0.001); and gastrojejunal ulcer (7.6% vs. 2.0%; P less than 0.001). Multivariate results showed that IDA patients were more likely to have a bariatric surgery complication over non-IDA patients (OR = 1.367, 95% CI = 1.257-1.487; P less than 0.05). Adjusted results showed IDA patients more than twice as likely to be hospitalized (OR = 2.567, 95% CI = 2.363-2.790; P less than 0.05). Total costs were twice as much in the IDA group compared with the non-IDA group ($37,882 vs. $19,253; P less than 0.001).  CONCLUSIONS: Bariatric surgery patients who develop IDA may be subject to higher complication rates, MRU, and direct medical costs. Although most bariatric surgery patients who develop IDA are tested for iron, most are not treated with IV iron or oral iron and do not receive blood transfusions. Further research is needed to determine if IDA is a result of bariatric surgery complications or a predictor of increased MRU and costs.


Assuntos
Anemia Ferropriva/epidemiologia , Cirurgia Bariátrica , Efeitos Psicossociais da Doença , Obesidade/cirurgia , Adulto , Anemia Ferropriva/economia , Anemia Ferropriva/etiologia , Estudos de Coortes , Feminino , Custos de Cuidados de Saúde , Recursos em Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Compostos de Ferro/uso terapêutico , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia
12.
Urol Pract ; 2(4): 149-153, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37559269

RESUMO

INTRODUCTION: We determined the clinical impact and value of routine histopathological examination of the foreskin following circumcision. METHODS: We performed a retrospective study of 225 consecutive adult circumcisions. Indications for circumcision were categorized as benign or malignant based on preoperative clinical evaluation. Histopathological results were similarly classified as benign or malignant. Preoperative clinical impression and postoperative histological diagnosis were compared and reported as concordant (in agreement) or discordant (in disagreement). The cost impact of histopathology examination was analyzed with respect to study findings. RESULTS: Of the 225 patients 209 (92.9%) had clinically benign disease on preoperative evaluation and 16 (7.1%) had foreskin lesions suspicious for malignancy. Mean age was 57.0 years (range 23 to 92). Patients were younger in the benign group than in the malignant group (56.5 vs 62.8 years, p = 0.018). Black patients represented 65.8% of the study population and were similarly distributed between the 2 groups (p = 0.405). There was no statistical difference in patient height, weight, body mass index or comorbidities between the 2 groups. Preoperative clinical impression and postoperative histological diagnosis were concordant in all 209 patients in the benign group. Of the 16 patients suspected to have malignant disease preoperatively 9 (56.2%) had malignancy and 7 (43.8%) had benign disease on histopathological examination. CONCLUSIONS: Routine histological examination of a foreskin specimen in the absence of clinical suspicion for malignancy appears to have diminished benefit in the setting of benign preoperative indications. Omitting this traditional practice in patients with benign surgical indications may positively impact health care costs without compromising quality of care.

13.
Int J Psychiatry Med ; 47(3): 231-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25084819

RESUMO

OBJECTIVE: Alcohol misuse is common among primary care patients, yet many do not receive treatment because doctors believe problem drinkers are "in denial," or are unwilling to change their drinking habits. The real problem, however, may be that patients are being offered treatment modalities that do not meet their needs. This study was designed to measure the acceptability of various treatment options among drinkers who were currently not receiving treatment. METHOD: Patients in a primary care clinic were given a self-report questionnaire that included: (1) the Alcohol Use Disorders Questionnaire, (2) a measure of readiness to change drinking behavior, and (3) a list of treatment modalities to be rated based on level of interest. RESULTS: Within a random sample of 402 patients, 40.2% reported high risk drinking and 16.3% reported problem drinking. Among the latter group, 89.3% were either considering change, or had begun to take steps to make changes in their drinking behaviors. When asked about treatment preferences, the modalities most frequently recommended by physicians-group therapy and Alcoholics Anonymous-were among the least acceptable. The most popular options were getting help from a primary care doctor and taking a medication that would make it easier to avoid drinking without making them sick if they drank. CONCLUSIONS: The belief that problem drinkers are unwilling to change was not supported by this study. Treatment for problem drinking should involve a collaborative evaluation of options with an emphasis on patient preference and treatment within the primary care setting.


Assuntos
Alcoolismo/reabilitação , Preferência do Paciente , Atenção Primária à Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alcoólicos Anônimos , Alcoolismo/diagnóstico , Alcoolismo/psicologia , Negação em Psicologia , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Motivação , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Psicometria , Psicoterapia de Grupo , Inquéritos e Questionários , Adulto Jovem
14.
Proc Natl Acad Sci U S A ; 110(18): E1695-704, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23580618

RESUMO

Identification of genes that control root system architecture in crop plants requires innovations that enable high-throughput and accurate measurements of root system architecture through time. We demonstrate the ability of a semiautomated 3D in vivo imaging and digital phenotyping pipeline to interrogate the quantitative genetic basis of root system growth in a rice biparental mapping population, Bala × Azucena. We phenotyped >1,400 3D root models and >57,000 2D images for a suite of 25 traits that quantified the distribution, shape, extent of exploration, and the intrinsic size of root networks at days 12, 14, and 16 of growth in a gellan gum medium. From these data we identified 89 quantitative trait loci, some of which correspond to those found previously in soil-grown plants, and provide evidence for genetic tradeoffs in root growth allocations, such as between the extent and thoroughness of exploration. We also developed a multivariate method for generating and mapping central root architecture phenotypes and used it to identify five major quantitative trait loci (r(2) = 24-37%), two of which were not identified by our univariate analysis. Our imaging and analytical platform provides a means to identify genes with high potential for improving root traits and agronomic qualities of crops.


Assuntos
Mapeamento Cromossômico , Genoma de Planta/genética , Imageamento Tridimensional , Oryza/anatomia & histologia , Oryza/genética , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/genética , Locos de Características Quantitativas/genética , Biomassa , Cruzamentos Genéticos , Endogamia , Modelos Biológicos , Análise Multivariada , Oryza/crescimento & desenvolvimento , Fenótipo , Raízes de Plantas/crescimento & desenvolvimento , Análise de Componente Principal , Característica Quantitativa Herdável , Recombinação Genética/genética , Reprodutibilidade dos Testes
15.
PLoS One ; 8(2): e57142, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23451165

RESUMO

The fundamental phenotypes of growth rate, size and morphology are the result of complex interactions between genotype and environment. We developed a high-throughput software application, WormSizer, which computes size and shape of nematodes from brightfield images. Existing methods for estimating volume either coarsely model the nematode as a cylinder or assume the worm shape or opacity is invariant. Our estimate is more robust to changes in morphology or optical density as it only assumes radial symmetry. This open source software is written as a plugin for the well-known image-processing framework Fiji/ImageJ. It may therefore be extended easily. We evaluated the technical performance of this framework, and we used it to analyze growth and shape of several canonical Caenorhabditis elegans mutants in a developmental time series. We confirm quantitatively that a Dumpy (Dpy) mutant is short and fat and that a Long (Lon) mutant is long and thin. We show that daf-2 insulin-like receptor mutants are larger than wild-type upon hatching but grow slow, and WormSizer can distinguish dauer larvae from normal larvae. We also show that a Small (Sma) mutant is actually smaller than wild-type at all stages of larval development. WormSizer works with Uncoordinated (Unc) and Roller (Rol) mutants as well, indicating that it can be used with mutants despite behavioral phenotypes. We used our complete data set to perform a power analysis, giving users a sense of how many images are needed to detect different effect sizes. Our analysis confirms and extends on existing phenotypic characterization of well-characterized mutants, demonstrating the utility and robustness of WormSizer.


Assuntos
Nematoides/anatomia & histologia , Animais , Mutação , Nematoides/genética , Software
16.
Nat Methods ; 9(11): 1101-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23023597

RESUMO

To fully describe gene expression dynamics requires the ability to quantitatively capture expression in individual cells over time. Automated systems for acquiring and analyzing real-time images are needed to obtain unbiased data across many samples and conditions. We developed a microfluidics device, the RootArray, in which 64 Arabidopsis thaliana seedlings can be grown and their roots imaged by confocal microscopy over several days without manual intervention. To achieve high throughput, we decoupled acquisition from analysis. In the acquisition phase, we obtain images at low resolution and segment to identify regions of interest. Coordinates are communicated to the microscope to record the regions of interest at high resolution. In the analysis phase, we reconstruct three-dimensional objects from stitched high-resolution images and extract quantitative measurements from a virtual medial section of the root. We tracked hundreds of roots to capture detailed expression patterns of 12 transgenic reporter lines under different conditions.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Raízes de Plantas/metabolismo , Arabidopsis , Técnicas Analíticas Microfluídicas , Microscopia Confocal/métodos
17.
BMC Plant Biol ; 12: 116, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-22834569

RESUMO

BACKGROUND: Characterizing root system architecture (RSA) is essential to understanding the development and function of vascular plants. Identifying RSA-associated genes also represents an underexplored opportunity for crop improvement. Software tools are needed to accelerate the pace at which quantitative traits of RSA are estimated from images of root networks. RESULTS: We have developed GiA Roots (General Image Analysis of Roots), a semi-automated software tool designed specifically for the high-throughput analysis of root system images. GiA Roots includes user-assisted algorithms to distinguish root from background and a fully automated pipeline that extracts dozens of root system phenotypes. Quantitative information on each phenotype, along with intermediate steps for full reproducibility, is returned to the end-user for downstream analysis. GiA Roots has a GUI front end and a command-line interface for interweaving the software into large-scale workflows. GiA Roots can also be extended to estimate novel phenotypes specified by the end-user. CONCLUSIONS: We demonstrate the use of GiA Roots on a set of 2393 images of rice roots representing 12 genotypes from the species Oryza sativa. We validate trait measurements against prior analyses of this image set that demonstrated that RSA traits are likely heritable and associated with genotypic differences. Moreover, we demonstrate that GiA Roots is extensible and an end-user can add functionality so that GiA Roots can estimate novel RSA traits. In summary, we show that the software can function as an efficient tool as part of a workflow to move from large numbers of root images to downstream analysis.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Oryza/anatomia & histologia , Raízes de Plantas/anatomia & histologia , Software , Algoritmos , Processamento Eletrônico de Dados , Genótipo , Oryza/crescimento & desenvolvimento , Fenótipo , Raízes de Plantas/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Interface Usuário-Computador , Fluxo de Trabalho
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