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1.
Planta ; 259(6): 150, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727772

RESUMO

MAIN CONCLUSION: The hop phenological cycle was described in subtropical condition of Brazil showing that flowering can happen at any time of year and this was related to developmental molecular pathways. Hops are traditionally produced in temperate regions, as it was believed that vernalization was necessary for flowering. Nevertheless, recent studies have revealed the potential for hops to flower in tropical and subtropical climates. In this work, we observed that hops in the subtropical climate of Minas Gerais, Brazil grow and flower multiple times throughout the year, independently of the season, contrasting with what happens in temperate regions. This could be due to the photoperiod consistently being inductive, with daylight hours below the described threshold (16.5 h critical). We observed that when the plants reached 7-9 nodes, the leaves began to transition from heart-shaped to trilobed-shaped, which could be indicative of the juvenile to adult transition. This could be related to the fact that the 5th node (in plants with 10 nodes) had the highest expression of miR156, while two miR172s increased in the 20th node (in plants with 25 nodes). Hop flowers appeared later, in the 25th or 28th nodes, and the expression of HlFT3 and HlFT5 was upregulated in plants between 15 and 20 nodes, while the expression of HlTFL3 was upregulated in plants with 20 nodes. These results indicate the role of axillary meristem age in regulating this process and suggest that the florigenic signal should be maintained until the hop plants bloom. In addition, it is possible that the expression of TFL is not sufficient to inhibit flowering in these conditions and promote branching. These findings suggest that the reproductive transition in hop under inductive photoperiodic conditions could occur in plants between 15 and 20 nodes. Our study sheds light on the intricate molecular mechanisms underlying hop floral development, paving the way for potential advancements in hop production on a global scale.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Humulus , Fotoperíodo , Folhas de Planta , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Humulus/genética , Humulus/crescimento & desenvolvimento , Humulus/fisiologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Estações do Ano , Brasil , MicroRNAs/genética , MicroRNAs/metabolismo , Clima Tropical
2.
Zootaxa ; 5399(3): 254-264, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38221158

RESUMO

Booralana nickorum sp. nov. is described from the deep-water slope of the Exuma Sound, The Bahamas, from depths of 540 to 560 metres. It is the fourth species to be assigned to the genus and the second species described from the Western North Atlantic. The species can be distinguished from Booralana tricarinata Camp and Heard, 1988 and the other species by the sub-triangular pleotelson and the uropodal exopod of mature males being far longer than endopod, with both rami extending well beyond the posterior margin of the pleotelson. Additionally, pleopods 3 and 4 lack a prominent angle at midpoint of ramus.


Assuntos
Isópodes , Masculino , Animais , Bahamas , Crustáceos
3.
Radiology ; 263(2): 374-82, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22517955

RESUMO

PURPOSE: To develop a model incorporating dynamic contrast material-enhanced (DCE) and diffusion-weighted (DW) magnetic resonance (MR) imaging features to differentiate high-nuclear-grade (HNG) from non-HNG ductal carcinoma in situ (DCIS) in vivo. MATERIALS AND METHODS: This HIPAA-compliant study was approved by the institutional review board and requirement for informed consent was waived. A total of 55 pure DCIS lesions (19 HNG, 36 non-HNG) in 52 women who underwent breast MR imaging at 1.5 T with both DCE and DW imaging (b = 0 and 600 sec/mm(2)) were retrospectively reviewed. The following lesion characteristics were recorded or measured: DCE morphology, DCE maximum lesion size, peak initial enhancement at 90 seconds, worst-curve delayed enhancement kinetics, apparent diffusion coefficient (ADC), contrast-to-noise ratio (CNR) at DW imaging with b values of 0 and 600 sec/mm(2), and T2 signal effects (measured with CNR at b = 0 sec/mm(2)). Univariate and stepwise multivariate logistic regression modeling was performed to identify MR imaging features that optimally discriminated HNG from non-HNG DCIS. Discriminative abilities of models were compared by using the area under the receiver operating characteristic curve (AUC). RESULTS: HNG lesions exhibited larger mean maximum lesion size (P = .02) and lower mean CNR for images with b value of 600 sec/mm(2) (P = .004), allowing discrimination of HNG from non-HNG DCIS (AUC = 0.71 for maximum lesion size, AUC = 0.70 for CNR at b = 600 sec/mm(2)). Differences in CNR for images with b value of 0 sec/mm(2) (P = .025) without corresponding differences in ADC values were observed between HNG and non-HNG lesions. Peak initial enhancement was the only kinetic variable to approach significance (P = .05). No differences in lesion morphology (P = .11) or worst-curve delayed enhancement kinetics (P = .97) were observed. A multivariate model combining CNR for images with b value of 600 sec/mm(2) and maximum lesion size most significantly discriminated HNG from non-HNG (AUC = 0.81). CONCLUSION: The preliminary findings suggest that DCE and DW MR imaging features may aid in identifying patients with high-risk DCIS. Further study may yield a model combining MR characteristics with histopathologic data to facilitate lesion-specific targeted therapies. © RSNA, 2012.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Área Sob a Curva , Meios de Contraste , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Retrospectivos
4.
J Magn Reson Imaging ; 35(5): 1222-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22282269

RESUMO

PURPOSE: To compare breast MRI B(1) homogeneity at 3 Tesla (T) with and without dual-source parallel radiofrequency (RF) excitation. MATERIALS AND METHODS: After institutional review board approval, we evaluated 14 consecutive breast MR examinations performed at 3T that included three-dimensional B(1) maps created separately with conventional single-source and dual-source parallel RF excitation techniques. We measured B(1) values (expressed as % of intended B(1) ) on each B(1) map at nipple level in multiple bilateral locations: anterior, lateral, central, medial, and posterior. Mean whole breast and location specific B(1) values were calculated and compared between right and left breasts using paired t-test. RESULTS: Mean whole breast B(1) values differed significantly between right and left breasts with standard single-source RF excitation (difference L-R, Δ = 9.2%; P < 0.001) but not with dual-source parallel RF excitation (Δ = 2.3%; P = 0.085). Location specific B(1) values differed significantly between right and left on single-source in the lateral (P = 0.014), central (P = 0.0001), medial (P = 0.0013), and posterior (P < 0.0001) locations. Conversely, mean B(1) values differed significantly on dual-source parallel RF excitation for only the anterior (P = 0.030) and lateral (P = 0.0003) locations. CONCLUSION: B(1) homogeneity is improved with dual-source parallel RF excitation on 3T breast MRI when compared with standard single-source RF excitation technique.


Assuntos
Doenças Mamárias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Ondas de Rádio
5.
AJR Am J Roentgenol ; 198(4): W373-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22451576

RESUMO

OBJECTIVE: Breast density is documented to reduce sensitivity and specificity of mammography. However, little is known regarding the effect of normal background parenchymal enhancement on accuracy of breast MRI. The purpose of this study was to evaluate the effect of background parenchymal enhancement on MRI diagnostic performance. MATERIALS AND METHODS: A review of our established MRI data identified all women undergoing breast MRI from March 1, 2006, through June 30, 2007. Prospectively reported background parenchymal enhancement categories of minimal, mild, moderate, or marked (anticipated BI-RADS MRI lexicon definitions) and assessments were extracted from the database for each patient. Outcomes were determined by pathologic analysis, imaging, and linkage with the regional tumor registry with a minimum of 24 months of follow-up. Patients were dichotomized into categories of minimal or mild versus moderate or marked background parenchymal enhancement. Associations with patient age, abnormal interpretation rate, positive biopsy rate, cancer yield, sensitivity, and specificity were compared using chi-square and z score tests. RESULTS: The study cohort included 736 women. Moderate or marked background parenchymal enhancement was significantly more frequent among patients younger than 50 years compared with those 50 years old and older (39.7% vs 18.9%; p < 0.0001). Moderate or marked background parenchymal enhancement was also associated with a higher abnormal interpretation rate compared with minimal or mild background parenchymal enhancement (30.5% vs 23.3%; p = 0.046). Positive biopsy rate, cancer yield, sensitivity, and specificity were not significantly different according to background parenchymal enhancement category. CONCLUSION: Increased background parenchymal enhancement on breast MRI is associated with younger patient age and higher abnormal interpretation rate. However, it is not related to significant differences in positive biopsy rate, cancer yield, sensitivity, or specificity of MRI.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Biópsia , Distribuição de Qui-Quadrado , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Programa de SEER , Sensibilidade e Especificidade
6.
AJR Am J Roentgenol ; 199(3): 703-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22915415

RESUMO

OBJECTIVE: The purpose of this study was to compare the differences in kinetic assessments of lesions at breast MRI performed with higher and lower temporal resolution. MATERIALS AND METHODS: All consecutively evaluated BI-RADS category 4, 5, and 6 lesions imaged with breast MRI and pathologically confirmed from October 2005 to August 2009 were identified. Patients underwent MRI with one of two dynamic contrast-enhanced protocols: one with 90-second (October 2005-June 2006) and another with 180-second (July 2006-August 2009) temporal resolution. Studies were processed with a computer-aided evaluation system with initial and delayed contrast-enhanced time points with the k-space centered 90 and 450 seconds after contrast injection. Initial-phase peak enhancement, delayed-phase predominant curve type, and worst curve type were recorded and compared for benign and malignant lesions across protocols. RESULTS: The analysis set comprised 993 lesions: 145 imaged with the 90-second acquisition (17 benign, 28 ductal carcinoma in situ [DCIS], 100 invasive cancer) and 848 imaged with the 180-second acquisition (212 benign, 145 DCIS, 491 invasive cancer). Peak enhancement was significantly higher for both benign lesions (p = 0.01) and invasive cancers (p = 0.0008) with the 180-second protocol. Peak enhancement of DCIS was similar in the two protocols (p = 0.88). Delayed-phase kinetics were similar for the two protocols for both benign and malignant lesions when defined by predominant or worst curve type. CONCLUSION: Although it has lower temporal resolution, a 180-second acquisition may be preferable because it allows higher spatial resolution and captures higher initial-phase peak enhancement without loss of delayed-phase kinetic information.


Assuntos
Neoplasias da Mama/diagnóstico , Aumento da Imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Pessoa de Meia-Idade , Adulto Jovem
7.
Opflow ; 48(2): 6-7, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35573036

RESUMO

The familiar conveniences of information technology-time savings, mobility, economy, and flexibility-have become necessities for working and communicating during the COVID-19 pandemic. How can the water industry apply this new phase of technology to its best practices long after the pandemic has passed?

8.
Cell Mol Bioeng ; 15(6): 587-597, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36531862

RESUMO

Objective: The chondrogenic response of adipose-derived stem cells (ASCs) is often assessed using 3D micromass protocols that use upwards of hundreds of thousands of cells. Scaling these systems up for high-throughput testing is technically challenging and wasteful given the necessary cell numbers and reagent volumes. However, adopting microscale spheroid cultures for this purpose shows promise. Spheroid systems work with only thousands of cells and microliters of medium. Methods: Molded agarose microwells were fabricated using 2% w/v molten agarose and then equilibrated in medium prior to introducing cells. ASCs were seeded at 50, 500, 5k cells/microwell; 5k, 50k, cells/well plate; and 50k and 250k cells/15 mL centrifuge tube to compare chondrogenic responses across spheroid and micromass sizes. Cells were cultured in control or chondrogenic induction media. ASCs coalesced into spheroids/pellets and were cultured at 37 °C and 5% CO2 for 21 days with media changes every other day. Results: All culture conditions supported growth of ASCs and formation of viable cell spheroids/micromasses. More robust growth was observed in chondrogenic conditions. Sulfated glycosaminoglycans and collagen II, molecules characteristics of chondrogenesis, were prevalent in both 5000-cell spheroids and 250,000-cell micromasses. Deposition of collagen I, characteristic of fibrocartilage, was more prevalent in the large micromasses than small spheroids. Conclusions: Chondrogenic differentiation was consistently induced using high-throughput spheroid formats, particularly when seeding at cell densities of 5000 cells/spheroid. This opens possibilities for highly arrayed experiments investigating tissue repair and remodeling during or after exposure to drugs, toxins, or other chemicals. Supplementary Information: The online version contains supplementary material available at 10.1007/s12195-022-00746-8.

9.
JMIR Res Protoc ; 11(10): e40856, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36301603

RESUMO

BACKGROUND: Neuromuscular diseases, such as spinal muscular atrophy (SMA) and Duchenne muscular dystrophy (DMD), may result in the loss of motor movements, respiratory failure, and early mortality in young children and in adulthood. With novel treatments now available, new evaluation methods are needed to assess progress that is not currently captured in existing motor scale tests. OBJECTIVE: With our feasibility study, our interdisciplinary team of investigators aims to develop a novel, multimodal paradigm of measuring motor function in children with neuromuscular diseases that will revolutionize the way that clinical trial end points are measured, thereby accelerating the pipeline of new treatments for childhood neuromuscular diseases. Through the Upper Extremity Examination for Neuromuscular Diseases (U-EXTEND) study, we hypothesize that the novel objective measures of upper extremity muscle structure and function proposed herein will be able to capture small changes and differences in function that cannot be measured with current clinical metrics. METHODS: U-EXTEND introduces a novel paradigm in which concrete, quantitative measures are used to assess motor function in patients with SMA and DMD. Aim 1 will focus on the use of ultrasound techniques to study muscle size, quality, and function, specifically isolating the biceps and pronator muscles of the upper extremities for follow-ups over time. To achieve this, clinical investigators will extract a set of measurements related to muscle structure, quality, and function by using ultrasound imaging and handheld dynamometry. Aim 2 will focus on leveraging wearable wireless sensor technology to capture motion data as participants perform activities of daily living. Measurement data will be examined and compared to those from a healthy cohort, and a motor function score will be calculated. RESULTS: Data collection for both aims began in January 2021. As of July 2022, we have enrolled 44 participants (9 with SMA, 20 with DMD, and 15 healthy participants). We expect the initial results to be published in summer 2022. CONCLUSIONS: We hypothesize that by applying the described tools and techniques for measuring muscle structure and upper extremity function, we will have created a system for the precise quantification of changes in motor function among patients with neuromuscular diseases. Our study will allow us to track the minimal clinically important difference over time to assess progress in novel treatments. By comparing the muscle scores and functional scores over multiple visits, we will be able to detect small changes in both the ability of the participants to perform the functional tasks and their intrinsic muscle properties. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/40856.

10.
Plants (Basel) ; 11(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35567239

RESUMO

MADS-box transcription factors (TFs) are involved in multiple plant development processes and are most known during the reproductive transition and floral organ development. Very few genes have been characterized in the genome of Humulus lupulus L. (Cannabaceae), an important crop for the pharmaceutical and beverage industries. The MADS-box family has not been studied in this species yet. We identified 65 MADS-box genes in the hop genome, of which 29 encode type-II TFs (27 of subgroup MIKCC and 2 MIKC*) and 36 type-I proteins (26 α, 9 ß, and 1 γ). Type-II MADS-box genes evolved more complex architectures than type-I genes. Interestingly, we did not find FLOWERING LOCUS C (FLC) homologs, a transcription factor that acts as a floral repressor and is negatively regulated by cold. This result provides a molecular explanation for a previous work showing that vernalization is not a requirement for hop flowering, which has implications for its cultivation in the tropics. Analysis of gene ontology and expression profiling revealed genes potentially involved in the development of male and female floral structures based on the differential expression of ABC homeotic genes in each whorl of the flower. We identified a gene exclusively expressed in lupulin glands, suggesting a role in specialized metabolism in these structures. In toto, this work contributes to understanding the evolutionary history of MADS-box genes in hop, and provides perspectives on functional genetic studies, biotechnology, and crop breeding.

11.
Front Plant Sci ; 13: 824948, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463406

RESUMO

Coffee (Coffea arabica L.) presents an asynchronous flowering regulated by an endogenous and environmental stimulus, and anthesis occurs once plants are rehydrated after a period of water deficit. We evaluated the evolution of Abscisic Acid (ABA), ethylene, 1-aminocyclopropane-1-carboxylate (ACC) content, ACC oxidase (ACO) activity, and expression analysis of the Lysine Histidine Transporter 1 (LHT1) transporter, in the roots, leaves, and flower buds from three coffee genotypes (C. arabica L. cv Oeiras, Acauã, and Semperflorens) cultivated under field conditions with two experiments. In a third field experiment, the effect of the exogenous supply of ACC in coffee anthesis was evaluated. We found an increased ACC level, low ACO activity, decreased level of ethylene, and a decreased level of ABA in all tissues from the three coffee genotypes in the re-watering period just before anthesis, and a high expression of the LHT1 in flower buds and leaves. The ethylene content and ACO activity decreased from rainy to dry period whereas the ABA content increased. A higher number of opened and G6 stage flower buds were observed in the treatment with exogenous ACC. The results showed that the interaction of ABA-ACO-ethylene and intercellular ACC transport among the leaves, buds, and roots in coffee favors an increased level of ACC that is most likely, involved as a modulator in coffee anthesis. This study provides evidence that ACC can play an important role independently of ethylene in the anthesis process in a perennial crop.

12.
Eur Radiol ; 21(8): 1609-17, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21359910

RESUMO

OBJECTIVES: To predict the probability of malignancy for MRI-detected breast lesions with a multivariate model incorporating patient and lesion characteristics. METHODS: Retrospective review of 2565 breast MR examinations from 1/03-11/06. BI-RADS 3, 4 and 5 lesions initially detected on MRI for new cancer or high-risk screening were included and outcomes determined by imaging, biopsy or tumor registry linkage. Variables were indication for MRI, age, lesion size, BI-RADS lesion type and kinetics. Associations with malignancy were assessed using generalized estimating equations and lesion probabilities of malignancy were calculated. RESULTS: 855 lesions (155 malignant, 700 benign) were included. Strongest associations with malignancy were for kinetics (washout versus persistent; OR 4.2, 95% CI 2.5-7.1) and clinical indication (new cancer versus high-risk screening; OR 3.0, 95% CI 1.7-5.1). Also significant were age > = 50 years, size > = 10 mm and lesion-type mass. The most predictive model (AUC 0.70) incorporated indication, size and kinetics. The highest probability of malignancy (41.1%) was for lesions on MRI for new cancer, > = 10 mm with washout. The lowest (1.2%) was for lesions on high-risk screening, <10 mm with persistent kinetics. CONCLUSIONS: A multivariate model shows promise as a decision support tool in predicting malignancy for MRI-detected breast lesions.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Logísticos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Probabilidade , Curva ROC , Estudos Retrospectivos
13.
Eur Radiol ; 21(9): 2011-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21562806

RESUMO

OBJECTIVES: To characterize ductal carcinoma in situ (DCIS) and its subtypes on diffusion-weighted imaging (DWI). METHODS: We retrospectively reviewed 74 pure DCIS lesions in 69 women who underwent DWI at 1.5 T (b = 0 and 600 s/mm(2)). Each lesion was characterized by qualitative DWI intensity, quantitative DWI lesion-to-normal contrast-to-noise ratio (CNR), and quantitative apparent diffusion coefficient (ADC). The detection rate was calculated with predetermined thresholds for each parameter. The effects of lesion size, grade, morphology, and necrosis were assessed. RESULTS: Ninety-six percent (71/74) of DCIS lesions demonstrated greater qualitative DWI intensity than normal breast tissue. Quantitatively, DCIS lesions demonstrated on average 56% greater signal than normal tissue (mean CNR = 1.83 ± 2.7) and lower ADC values (1.50 ± 0.28 × 10(-3) mm(2)/s) than normal tissue (2.01 ± 0.37 × 10(-3) mm(2)/s, p < 0.0001). A 91% detection rate was achieved utilizing an ADC threshold (<1.81 × 10(-3) mm(2)/s ). Non-high-grade DCIS exhibited greater qualitative DWI intensity (p = 0.02) and quantitative CNR (p = 0.01) than high-grade DCIS but no difference in ADC (p = 0.40). Lesion size, morphology, and necrosis did not affect qualitative or quantitative DWI parameters of DCIS lesions (p > 0.05). CONCLUSIONS: DCIS lesions have higher DWI signal intensity and lower ADC values than normal breast tissue. DWI warrants further investigation as a potential non-contrast MRI tool for early breast cancer detection.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Estudos de Coortes , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Valores de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
AJR Am J Roentgenol ; 196(1): W93-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21178040

RESUMO

OBJECTIVE: The purpose of our study is to report the outcomes at a center that routinely uses breast MRI for preoperative staging, regardless of lesion histology or patient characteristics. MATERIALS AND METHODS: Five hundred ninety-two patients with recently diagnosed breast cancer who underwent staging with preoperative breast MRI between January 1, 2003, and April 30, 2007, were reviewed. Five hundred seventy patients comprised the analysis set. Patient age, breast density, index tumor histology, receptor status (ER, PR, and HER2), and lymph node status were recorded. Biopsy rates, positive predictive values (PPVs) of biopsy, and overall cancer yield were calculated and compared using the chi-square test across patient age, mammographic breast density, index tumor type, receptor status, and lymph node status. RESULTS: Biopsy was recommended and performed for 152 of 570 (27%) patients found to have one or more suspicious lesions on MRI distinct from the index cancer. Sixty-seven of 152 women who underwent biopsy had additional cancers diagnosed, for a PPV of 44%. Overall, 12% (67/570) of women had otherwise occult cancers diagnosed by MRI, with 8% having additional sites or greater extent of ipsilateral disease and 4% having unsuspected contralateral cancer detected by MRI alone. No significant differences were found in the probability of detecting an occult cancer on the basis of patient age, breast density, index tumor characteristics, or lymph node status. CONCLUSION: Breast MRI detects otherwise occult cancer with an overall added cancer yield of 12% and a high PPV of 44% when applied to a diverse population of patients with newly diagnosed breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Distribuição de Qui-Quadrado , Meios de Contraste , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Achados Incidentais , Metástase Linfática , Mamografia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco
15.
Breast J ; 17(3): 273-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21477168

RESUMO

Breast magnetic resonance imaging (MRI) is routinely used as a problem-solving tool, but its benefit for this indication remains unclear. The records of 3001 consecutive breast MR examinations between January 1, 2003 and June 6, 2007 were reviewed to identify all those performed for the clinical indication of problem solving. Details of clinical presentation, mammography and ultrasound (US) findings, follow-up recommendations, and pathology outcomes were recorded. Benign versus malignant outcomes were determined by biopsy or 12 months of follow-up imaging and linkage with the regional tumor registry. Problem solving was the clinical indication for 204 of 3001 (7%) of all examinations. Forty-two of 204 examinations (21%) had suspicious or highly suspicious MRI assessments with recommendation for biopsy and 62 of 204 (79%) examinations were assessed as negative, benign, or probably benign. Thirty-six biopsies were performed based on MRI findings and 14 cancers were diagnosed. Biopsy was indicated for 11 of 14 (79%) cancers based on suspicious mammographic or US findings identified prior to MRI. One incidental cancer was detected by MRI alone in a patient at high risk for breast cancer, and two cancers were detected in patients with suspicious nipple discharge and negative mammogram and US. A single false-negative MRI occurred in a patient whose evaluation for a palpable lump prompted biopsy. Problem-solving breast MRI rarely identifies otherwise occult cancer and can be falsely negative in patients with suspicious findings on mammogram and US. Until the benefits and risks of problem-solving MRI are clarified, it should be used judiciously.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resolução de Problemas , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Biomaterials ; 270: 120684, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535143

RESUMO

Mechanical forces are an essential element to early tissue formation. However, few techniques exist that can quantify the mechanical microenvironment present within cell-dense neotissues and organoid structures. Here is a versatile approach to measure microscale, cellular forces during mesenchymal condensation using specially tailored, hyper-compliant microparticles (HCMPs). Through monitoring of HCMP deformation over both space and time, measurements of the mechanical forces that cells exert, and have exerted on them, during tissue formation are acquired. The current study uses this technology to track changes in the mechanical microenvironment as mesenchymal stem cells self-assemble into spheroids and condense into cohesive units. An array analysis approach, using a high-content imaging system, shows that cells exert a wide range of tensile and compressive forces during the first few hours of self-assembly, followed by a period of relative equilibrium. Cellular interactions with HCMPs are further examined by applying collagen coating, which allows for increased tensile forces to be exerted compared to non-coated HCMPs. Importantly, the hyper-compliant nature of our force sensors allows for increased precision over less compliant versions of the same particle. This sensitivity resolves small changes in the microenvironment even at the earliest stages of development and morphogenesis. The overall experimental platform provides a versatile means for measuring direct and indirect spatiotemporal forces in cell-dense biological systems.


Assuntos
Comunicação Celular , Fenômenos Mecânicos , Colágeno , Morfogênese
17.
Radiology ; 255(3): 723-30, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20173103

RESUMO

PURPOSE: To determine if patients with fewer than three foci of atypical ductal hyperplasia (ADH) who have all of their calcifications removed after stereotactic 9- or 11-gauge vacuum-assisted breast biopsy (VABB) have a rate of upgrade to malignancy that is sufficiently low to obviate surgical excision. MATERIALS AND METHODS: An institutional review board-approved, HIPAA-compliant retrospective review of 991 cases of consecutive 9- or 11-gauge stereotactic VABB performed during a 65-month period revealed 147 cases of atypia. One pathologist performed a blinded review of the results of procedures performed to assess for calcifications and confirmed ADH in 101 cases with subsequent surgical excision. Each large duct or terminal duct-lobular unit containing ADH was considered a focus and counted. Postbiopsy mammograms were reviewed to determine whether all calcifications were removed. Upgrade to malignancy was determined from excisional biopsy pathology reports. Upgrade rates as a function of both number of foci and presence or absence of residual calcifications were calculated and compared by using chi(2) tests. RESULTS: Upgrade to malignancy occurred in 20 (19.8%) of the 101 cases. The upgrade rate was significantly higher in cases of three or more foci of ADH (15 [28%] of 53 cases) than in cases of fewer than three foci (five [10%] of 48 cases) (P = .02). Upgrade rates were similar, regardless of whether all mammographic calcifications were removed (seven [17%] of 41 cases) or all were not removed (nine [20%] of 45 cases) (P = .77). Upgrade occurred in two (12%) of 17 cases in which there were fewer than three ADH foci and all calcifications were removed. CONCLUSION: The upgrade rate is significantly higher when ADH involves at least three foci. Surgical excision is recommended even when ADH involves fewer than three foci and all mammographic calcifications have been removed, because the upgrade rate is 12%.


Assuntos
Biópsia por Agulha Fina/instrumentação , Neoplasias da Mama/patologia , Mama/patologia , Carcinoma Ductal de Mama/patologia , Biópsia por Agulha Fina/estatística & dados numéricos , Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Calcinose/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/cirurgia , Distribuição de Qui-Quadrado , Feminino , Humanos , Mamografia , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Técnicas Estereotáxicas/estatística & dados numéricos
18.
AJR Am J Roentgenol ; 195(3): 792-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20729462

RESUMO

OBJECTIVE: The purpose of this article is to determine the frequency, outcomes, and imaging features of high-risk lesions initially detected by breast MRI, including atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ, and radial scar. MATERIALS AND METHODS: A retrospective review of our MRI pathology database was performed to identify all lesions initially detected with MRI (January 2003 through May 2007) that underwent imaging-guided needle biopsy yielding high-risk histopathologic abnormalities. Patient age, clinical indication, MRI BI-RADS lesion features, biopsy method, and histopathologic diagnosis were recorded. The frequencies of high-risk findings at needle biopsy and rates of upgrade to malignancy at surgical excision were compared across lesion imaging features with Fisher's exact test. RESULTS: Four hundred eighty-two MRI-detected suspicious lesions underwent needle biopsy. High-risk histopathologic abnormalities were present in 61 (12.7%) of 482 lesions: 51 (10.6%) atypical ductal hyperplasias, six (1.2%) atypical lobular hyperplasias, three (0.6%) lobular carcinomas in situ, and one (0.2%) radial scar. Correlation between the lesion site and pathology at surgical excision was confirmed for 39 of 61 lesions. Twelve (30.8%) of those 39 lesions were upgraded to malignancy (11 atypical ductal hyperplasias and one atypical lobular hyperplasia); five (41.7%) of the 12 malignancies were invasive cancer, and seven (58.3%) were ductal carcinomas in situ. No significant lesion features predictive of subsequent upgrade to malignancy were discovered. CONCLUSION: There are no specific imaging features that predict upgrade for high-risk lesions when detected with MRI. Therefore, surgical excision is recommended because upgrade to invasive carcinoma or ductal carcinoma in situ can occur in up to 31% of cases, regardless of biopsy technique.


Assuntos
Doenças Mamárias/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia por Agulha , Doenças Mamárias/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Distribuição de Qui-Quadrado , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Retrospectivos
19.
AJR Am J Roentgenol ; 195(6): 1472-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21098212

RESUMO

OBJECTIVE: The purpose of this article is to assess the accuracy of targeted breast ultrasound in women younger than 30 years presenting with focal breast signs or symptoms. MATERIALS AND METHODS: Retrospective review of the electronic medical records identified all ultrasound examinations from January 1, 2002, through August 30, 2006, performed for focal breast signs or symptoms in women younger than 30 years. BI-RADS assessments were recorded. Outcomes were determined by biopsy, 24 months of ultrasound surveillance, and linkage with the regional tumor registry. The overall cancer yield, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) 2, and PPV3 of ultrasound were calculated. RESULTS: Among 830 study patients, lesions were assessed as BI-RADS category 1 or 2 in 526 (63.4%), BI-RADS category 3 in 140 (16.9%), BI-RADS category 4 in 163 (19.6%), and BI-RADS category 5 in one (0.1%) patient. Three malignancies were detected, for a cancer yield of 0.4%. No BI-RADS category 3 lesions, two BI-RADS category 4 lesions, and the single BI-RADS category 5 lesion were malignant. Ultrasound sensitivity was 100%, specificity was 80.5%, NPV was 100%, PPV2 was 1.8%, and PPV3 was 1.9%. CONCLUSION: Women younger than 30 years with focal breast signs or symptoms have a very low (0.4%) incidence of malignancy. The 100% sensitivity and NPV of targeted ultrasound in our study substantiates its use as an accurate primary imaging test in this clinical setting. We found no malignancies in BI-RADS category 3 lesions, supporting ultrasound surveillance over biopsy in this patient population.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Adolescente , Adulto , Fatores Etários , Criança , Diagnóstico Diferencial , Feminino , Humanos , Valor Preditivo dos Testes , Sistema de Registros , Estudos Retrospectivos , Sensibilidade e Especificidade
20.
AJR Am J Roentgenol ; 193(3): 861-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19696303

RESUMO

OBJECTIVE: The purpose of our study was to describe the characteristics of probably benign breast MRI lesions and determine how these characteristics could be used to define the MRI BI-RADS 3 category. MATERIALS AND METHODS: We prospectively collected morphology and kinetic data on lesions assessed as BI-RADS 3 in 2,569 consecutive breast MRI examinations from January 2003 through November 2006. The clinical indications for MRI, follow-up assessments, and pathology findings through May 2008 were collected from clinical records. Data were linked to the regional tumor registry to identify cases of malignancy in patients who did not follow-up at our institution. Frequency of BI-RADS 3 and cancer yield were calculated. Characteristics of probably benign lesions were analyzed for predictors of malignancy. RESULTS: Three hundred sixty-two lesions were assessed as BI-RADS 3 in 260 (10.1%) of 2,569 examinations in 236 patients. The 362 lesions included 168 (46%) foci, 132 (36%) nonmasslike enhancements, and 62 (17%) masses. Delayed kinetic information was available in 275 lesions. The most suspicious delayed kinetic enhancement was persistent in 164 (60%) of 275, plateau in 47 (17%) of 275, and washout in 64 (23%) of 275. The cancer yield in patients with a BI-RADS 3 assessment was two (0.85%) of 236; both were ductal carcinoma in situ lesions. There were no malignancies in the 69 foci with 100% persistent enhancement. CONCLUSION: The characteristics of BI-RADS 3 lesions were highly variable in our population, and the risk of malignancy was low (0.85%). Assigning foci with 100% persistent enhancement to the BI-RADS 2 category can decrease the frequency of BI-RADS 3 assessment and maintain a likelihood of malignancy in less than 2% of cases.


Assuntos
Doenças Mamárias/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Meios de Contraste/farmacocinética , Diagnóstico Diferencial , Feminino , Gadolínio DTPA/farmacocinética , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Estudos Retrospectivos
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