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1.
Theor Appl Genet ; 137(3): 55, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386094

RESUMO

KEY MESSAGE: The first single dominant resistance gene contributing major resistance to the oomycete pathogen Phytophthora sansomeana was identified and mapped from soybean 'Colfax'. Phytophthora root rot (PRR) is one of the most important diseases in soybean (Glycine max). PRR is well known to be caused by Phytophthora sojae, but recent studies showed that P. sansomeana also causes extensive root rot of soybean. Depending upon the isolate, it might produce aggressive symptoms, especially in seeds and seedlings. Unlike P. sojae which can be effectively managed by Rps genes, no known major resistance genes have yet been reported for P. sansomeana. Our previous study screened 470 soybean germplasm lines for resistance to P. sansomeana and found that soybean 'Colfax' (PI 573008) carries major resistance to the pathogen. In this study, we crossed 'Colfax' with a susceptible parent, 'Senaki', and developed three mapping populations with a total of 234 F2:3 families. Inheritance pattern analysis indicated a 1:2:1 ratio for resistant: segregating: susceptible lines among all the three populations, indicating a single dominant gene conferring the resistance in 'Colfax' (designated as Rpsan1). Linkage analysis using extreme phenotypes anchored Rpsan1 to a 30 Mb region on chromosome 3. By selecting nine polymorphic SNP markers within the region, Rpsan1 was genetically delimited into a 21.3 cM region between Gm03_4487138_A_C and Gm03_5451606_A_C, which corresponds to a 1.06 Mb genomic region containing nine NBS-LRR genes based on Gmax2.0 assembly. The mapping results were then validated using two breeding populations derived from 'E12076T-03' × 'Colfax' and 'E16099' × 'Colfax'. Marker-assisted resistance spectrum analyses with 9 additional isolates of P. sansomeana indicated that Rpsan1 may be effective towards a broader range of P. sansomeana isolates and has strong merit in protecting soybean to this pathogen in the future.


Assuntos
Glycine max , Phytophthora , Humanos , Glycine max/genética , Melhoramento Vegetal , Genes Dominantes , Genômica
2.
Sci Rep ; 13(1): 18047, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872226

RESUMO

A key parameter of interest recovered from hyperpolarized (HP) MRI measurements is the apparent pyruvate-to-lactate exchange rate, [Formula: see text], for measuring tumor metabolism. This manuscript presents an information-theory-based optimal experimental design approach that minimizes the uncertainty in the rate parameter, [Formula: see text], recovered from HP-MRI measurements. Mutual information is employed to measure the information content of the HP measurements with respect to the first-order exchange kinetics of the pyruvate conversion to lactate. Flip angles of the pulse sequence acquisition are optimized with respect to the mutual information. A time-varying flip angle scheme leads to a higher parameter optimization that can further improve the quantitative value of mutual information over a constant flip angle scheme. However, the constant flip angle scheme, 35 and 28 degrees for pyruvate and lactate measurements, leads to an accuracy and precision comparable to the variable flip angle schemes obtained from our method. Combining the comparable performance and practical implementation, optimized pyruvate and lactate flip angles of 35 and 28 degrees, respectively, are recommended.

5.
Front Oncol ; 11: 711405, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765539

RESUMO

Brain metastases are a major clinical problem, and immunotherapy offers a novel treatment paradigm with the potential to synergize with existing focal therapies like surgery and radiosurgery or even replace them in future. The brain is a unique microenvironment structurally and immunologically. The immune response is likely to be crucial to the adaptation of systemic immune modulating agents against this disease. Imaging is frequently employed in the clinical diagnosis and management of brain metastasis, so it is logical that brain imaging techniques are investigated as a source of biomarkers of the immune response in these tumors. Current imaging techniques in clinical use include structural MRI (post-contrast T1W sequences, T2, and FLAIR), physiological sequences (perfusion- and diffusion-weighted imaging), and molecular imaging (MR spectroscopy and PET). These are reviewed for their application to predicting and measuring the response to immunotherapy in brain metastases.

6.
Ann Transl Med ; 9(5): 440, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33842661

RESUMO

B cells play many critical roles in the systemic immune response, including antibody secretion, antigen presentation, T cell co-stimulation, and pro- and anti-inflammatory cytokine production. However, the contribution of B cells to the local immune response in many non-lymphoid tissues, such as the skin, is incompletely understood. Cutaneous B cells are scarce except in certain malignant and inflammatory conditions, and as such, have been poorly characterized until recently. Emerging evidence now suggests an important role for cutaneous B in both skin homeostasis and pathogenesis of skin disease. Herein, we discuss the potential mechanisms for cutaneous B cell recruitment, localized antibody production, and T cell interaction in human skin infections and primary skin malignancies (i.e., melanoma, squamous cell carcinoma). We further consider the likely contribution of cutaneous B cells to the pathogenesis of inflammatory skin diseases, including pemphigus vulgaris, lupus erythematosus, systemic sclerosis, hidradenitis suppurativa, and atopic dermatitis. Finally, we examine the feasibility of B cell targeted therapy in the dermatologic setting, emphasizing areas that are still open to investigation. Through this review, we hope to highlight what we really know about cutaneous B cells in human skin, which can sometimes be lost in reviews that more broadly incorporate extensive data from animal models.

7.
Case Rep Dermatol Med ; 2021: 7598086, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763265

RESUMO

Nevus sebaceus of Jadassohn, or "organoid nevus," is a common, benign hamartoma of the skin consisting of epithelial and adnexal components. Its natural history and association with neoplastic growths is well documented. The majority of concomitant neoplasms are benign-trichoblastoma and syringocystadenoma papilliferum are most frequently discovered-but malignant tumors have been described. We present the case of a 58-year-old male with a congenital nevus sebaceus of Jadassohn on his left parietal scalp that had been enlarging, changing color, and bleeding over the prior year. Clinical exam and histology disclosed the presence of a trichoblastoma and porocarcinoma arising within the nevus sebaceus. Porocarcinoma is a rare, intermediately aggressive, malignant eccrine gland tumor that is frequently metastasized at presentation. Otolaryngology performed wide local resection with sentinel lymph node biopsy. This case highlights the diversity of tumors associated with nevus sebaceus of Jadassohn, potential for malignant expansion, and necessity for close monitoring and maintaining a low threshold for biopsy in evolving lesions.

8.
Phys Med Biol ; 65(22): 225008, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32947269

RESUMO

Acquisition parameter selection is currently performed empirically for many quantitative MRI (qMRI) acquisitions. Tuning parameters for different scan times, tissues, and resolutions requires some amount of trial and error. There is an opportunity to quantitatively optimize these acquisition parameters in order to minimize variability of quantitative maps and post-processing techniques such as synthetic image generation. The objective of this work is to introduce and evaluate a quantitative method for selecting parameters that minimize image variability. An information theory framework was developed for this purpose and applied to a 3D-quantification using an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) signal model for qMRI. In this framework, mutual information is used to measure the information gained by a measurement as a function of acquisition parameters, quantifying the information content of potential acquisitions and allowing informed parameter selection. The information theory framework was tested on artificial data generated from a representative mathematical phantom, measurements acquired on a qMRI multiparametric imaging standard phantom, and in vivo measurements in a human brain. The phantom measurements showed that higher mutual information calculated by the model correlated with smaller coefficient of variation in the reconstructed parametric maps, and in vivo measurements demonstrated that information-based calibration of acquisition parameters resulted in a decrease in parametric map variability consistent with model predictions.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Teoria da Informação , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Humanos
9.
PLoS One ; 15(3): e0230447, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32182272

RESUMO

Physical literacy is becoming increasingly popular in sport, recreation, physical education and physical activity settings and programming. We developed an environmental assessment tool to evaluate the extent child and youth activity programs implement physical literacy across four domains: environment, programming, leaders and staff, and values and goals. The Physical Literacy Environmental Assessment (PLEA) tool was developed in 3 phases. First, the PLEA tool was created, content validity established, and physical literacy leaders were consulted. In the second phase, the PLEA tool was completed and tested by 83 child and youth programs and it was validated with individual physical literacy assessments completed on children in programs that scored in the top 10% and bottom 10% on the PLEA tool. Third, a National consultation was conducted, and program leaders provided feedback on the PLEA tool. In Phase 1, the PLEA tool was modified and shortened from 41 to 29 indicators, based on feedback from physical literacy content leaders. In Phase 2, participants in programs that scored in the top 10% had significantly higher scores on the upper body object control domain of PLAYfun (p = 0.018), and significantly higher PLAYself scores (p = 0.04) than participants in programs that scored in the bottom 10%. In Phase 3, over 80% of program leaders identified the PLEA tool was useful, and relevant to their areas of practice. The completed PLEA tool is a 20-item environmental assessment tool to evaluate to what degree child and youth programming implement physical literacy across four domains: environment, programming, leaders and staff, and values and goals. The application and validity of the PLEA tool beyond child and youth physical education, sport, dance and recreation sectors, such as in early years programs, should be investigated.


Assuntos
Letramento em Saúde/métodos , Educação Física e Treinamento/métodos , Exercício Físico , Feminino , Humanos , Masculino , Esportes/educação
10.
Ann Plast Surg ; 85(S1 Suppl 1): S122-S126, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32205492

RESUMO

INTRODUCTION: Current microsurgical training courses average 5 consecutive 8-hour days and cost US $1500 to US $2500/individual, making training a challenge for residents who are unable to take leave from clinical duties. This residency-integrated microsurgery course was designed for integration with a residency program, averaging 3 hours/week over 7 weeks. This allows for one-on-one training, beginning with synthetic tissue and concluding with in vivo stimulation. This study was performed to validate this longitudinal training course. METHODS: After recruitment and before the start of coursework, subjects completed a baseline anastomosis without guidance and a survey regarding microsurgical experience. Subjects completed approximately 3 hours/week of practical exercises. Weeks 1 to 5 used synthetic models, whereas 6 to 7 used in vivo rodent models. Nine minimum anastomoses of increasing complexity were completed and assessed with the Anastomosis Lapse Index and the Stanford Microsurgery and Residency Training scale. Scoring was performed by 3 independent reviewers and averaged for comparison. RESULTS: Five subjects completed the course for study. Presurvey results showed an average confidence in theoretical knowledge of 2/5; technical ability to perform procedures, 1.8/5; and ability to manage complications, 1.8/5. Postsurvey revealed confidence in theoretical knowledge of 2.5/5; technical ability to perform procedures, 2.25/5; and ability to manage complications, 2.25/5. None of these differences were significant. Each individual component of the Stanford Microsurgery and Residency Training scale scoring system improved postcourse with P < 0.05, and overall performance score improved from an average of 2.6 to 3.9 (P = 0.006). The total number of errors recorded using the Anastomosis Lapse Index reduced from 6.58 to 3.41 (P = 0.02). Time to completion reduced from an average of 28 minutes, 8 seconds to 24 minutes, 5 seconds (P = 0.003). CONCLUSIONS: Despite a lack in significant confidence improvement, completion of the residency-integrated microsurgery course leads to significant and quantifiable improvement in resident microsurgical skill and efficiency.


Assuntos
Internato e Residência , Anastomose Cirúrgica , Competência Clínica , Currículo , Microcirurgia
12.
Ann Plast Surg ; 82(4S Suppl 3): S202-S207, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30855389

RESUMO

BACKGROUND: Breast conservation therapy is defined as partial mastectomy with subsequent radiation therapy and is the treatment for early-stage breast cancer. However, the unwanted risks of radiation must be considered as well as the impact on future breast reconstruction options. The purpose of this study was to assess the preference of plastic surgeons when given the hypothetical diagnosis of breast cancer. METHODS: A survey assessing treatment preference of 3 hypothetical breast cancer diagnosis scenarios was designed and distributed by American Society of Plastic Surgeons via e-mail invite to its members. RESULTS: The risk of cancer recurrence was the most common reason for treatment preferences of all three choices. However, for ductal carcinoma in situ, unilateral mastectomy with implant-based reconstruction is the preferred option with the second most influential reason of avoiding the risks of radiation therapy. For invasive ductal carcinoma node negative, unilateral mastectomy with implant-based reconstruction was the preferred option also due to risks of radiation therapy and anxiety of future surveillance. For invasive ductal carcinoma node positive, bilateral mastectomy with implant-based reconstruction was the preferred choice because of anxiety of future surveillance and also risks of radiation therapy. CONCLUSIONS: In general, plastic surgeons did not prefer breast conservation therapy for in situ and early-stage breast cancer. Although the most common rationale for total mastectomy was risk of cancer recurrence for all disease severity, risks of radiation therapy are real and play an integral role in the decision-making process. In understanding our own biases, we can help better empathize with patients in consultation for breast reconstruction.


Assuntos
Atitude do Pessoal de Saúde , Neoplasias da Mama/cirurgia , Comportamento de Escolha , Tomada de Decisão Clínica , Mastectomia Segmentar , Cirurgia Plástica , Adulto , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade
13.
Front Pediatr ; 6: 138, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29930933

RESUMO

Background: Physical literacy is essential to physical activity across the lifespan. While there is an emerging body of research on physical literacy in school-aged children, the preschool years have largely been ignored. We tested the psychometric properties of the new tool, the Preschool Physical Literacy Assessment Tool (Pre-PLAy) designed to address this gap. Methods: We recruted 78 children (aged 19-49 months) across 5 childcare centers in Hamilton, Ontario. Two Early Childhood Educators (ECE) completed the Pre-PLAy for each child at two points in time to assess inter-rater reliability and test-retest reliability. We assessed the agreement between the Pre-PLAy tool with gross motor skills and the ability of the PPLAy to predict physical activity. Results: Results indicated Pre-PLAy is related to gross motor skills and predictive of physical activity for females, but not males. Inter-rater and intra-rater reliability was at least adequate for all but the coordinated movements items and scale for females, but ECEs showed poor agreement for males. Conclusions: These results suggest initial support for the Pre-PLAy tool as a measure of physical literacy during the early years. However, some modification to the items and training are required to address the gender-specific effects found in this sample.

14.
Int J Hyperthermia ; 34(7): 943-952, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29343140

RESUMO

We evaluated a physics-based model for planning for magnetic resonance-guided laser interstitial thermal therapy for focal brain lesions. Linear superposition of analytical point source solutions to the steady-state Pennes bioheat transfer equation simulates laser-induced heating in brain tissue. The line integral of the photon attenuation from the laser source enables computation of the laser interaction with heterogeneous tissue. Magnetic resonance thermometry data sets (n = 31) were used to calibrate and retrospectively validate the model's thermal ablation prediction accuracy, which was quantified by the Dice similarity coefficient (DSC) between model-predicted and measured ablation regions (T > 57 °C). A Gaussian mixture model was used to identify independent tissue labels on pre-treatment anatomical magnetic resonance images. The tissue-dependent optical attenuation coefficients within these labels were calibrated using an interior point method that maximises DSC agreement with thermometry. The distribution of calibrated tissue properties formed a population model for our patient cohort. Model prediction accuracy was cross-validated using the population mean of the calibrated tissue properties. A homogeneous tissue model was used as a reference control. The median DSC values in cross-validation were 0.829 for the homogeneous model and 0.840 for the heterogeneous model. In cross-validation, the heterogeneous model produced a DSC higher than that produced by the homogeneous model in 23 of the 31 brain lesion ablations. Results of a paired, two-tailed Wilcoxon signed-rank test indicated that the performance improvement of the heterogeneous model over that of the homogeneous model was statistically significant (p < 0.01).


Assuntos
Terapia a Laser/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
BMC Geriatr ; 18(1): 13, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29338694

RESUMO

BACKGROUND: Arguably the uptake and usability of the physical activity (PA) guidelines for older adults has not been effective with only 12% of this population meeting the minimum guidelines to maintain health. Health promoters must consider innovative ways to increase PA adoption and long-term sustainability. Physical literacy (PL) is emerging as a promising strategy to increase lifelong PA participation in younger age-groups, yet there is relatively little evidence of PL being used to support older adults in achieving the PA guidelines. METHODS: An iterative and mixed-methods consensus development process was utilized over a series of six informed processes and meetings to develop a model of physical literacy for adults aged 65 years and older. RESULTS: A multi-disciplinary collaborative working group (n = 9) from diverse practice settings across Canada, and representative and reflective of the full range of key elements of PL, was assembled. Three consensus meetings and two Delphi surveys, using an international cohort of 65 expert researchers, practitioners, non-government organizations and older adults, was conducted. 45% responded on the first round and consensus was achieved; however, we elected to run a second survey to support our results. With 79% response rate, there was consensus to support the new PL model for older adults. CONCLUSION: Older adults are a unique group who have yet to be exposed to PL as a means to promote long-term PA participation. This new PL model uses an ecological approach to integrate PL into the lifestyles of most older adults. Understanding the interactions between components and elements that facilitate PL will ultimately provide a new and effective tool to target PA promotion and adherence for all older Canadians.


Assuntos
Envelhecimento , Exercício Físico , Comportamentos Relacionados com a Saúde , Letramento em Saúde/métodos , Promoção da Saúde/métodos , Estilo de Vida Saudável , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Canadá , Consenso , Técnica Delphi , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Humanos , Participação Social/psicologia
16.
J Gastroenterol Hepatol ; 20(1): 79-86, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15610451

RESUMO

BACKGROUND AND AIM: Of the estimated 160,000 Australians currently infected with hepatitis C virus (HCV), two-thirds are men. Little is known about their social and health needs. The present study presents results from a comprehensive survey of Australian men living with HCV. METHODS: In 2002, a self-administered questionnaire was completed by a largely non-clinical sample of men living in the State of Victoria who had tested positive for HCV antibodies (n = 308). The return rate was 54%. The mean age was 38 years (standard deviation [SD] = 9.8; range 19-90 years), and 86% were 'current' or 'past' injecting drug users. The mean number of years since diagnosis was 6.6 years (SD = 5.0) and the mean self-reported number of years since infection was 12.6 years (SD = 9.2). RESULTS: Fifty percent of men reported experiencing HCV-related symptoms, most commonly tiredness (61%) and nausea (30%). Of the sample, 43% currently saw a doctor for HCV and although 30% had ever been referred to a specialist, few had received treatment (6% interferon; 14% combination therapy). Forty percent of men reported that they believed they received less favorable treatment from health care professionals than those without HCV. Self-assessed health status was significantly lower than Australian norms, as were SF-12 physical and mental health scores. Scores were moderately correlated, indicating an association between the physical and mental health burden of HCV. CONCLUSION: The social, physical and mental health needs of men living with HCV are considerable. Few men in the present study had accessed specialist treatment; those who were current injecting drug users were particularly disadvantaged. Reduction of barriers to primary and specialist health care is essential to improve treatment, support and care for men with HCV.


Assuntos
Hepatite C/terapia , Qualidade de Vida , Acesso à Informação , Austrália , Estudos Transversais , Atenção à Saúde , Humanos , Relações Interpessoais , Masculino , Apoio Social , Inquéritos e Questionários
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