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1.
Biomarkers ; 28(3): 313-322, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36647745

RESUMEN

BACKGROUND: Some patients with metastatic breast cancer (MBC) stay on endocrine therapy (ET) for years and others progress quickly. Serum thymidine kinase activity (TKa), an indicator of cell-proliferation, is a potential biomarker for monitoring ET and predicting MBC outcome. We have previously reported TKa as being prognostic in MBC in SWOG S0226. Here, new data on progression within 30/60 days post sampling, with a new, FDA approved version of DiviTum®TKa highlighting differences vs. a Research Use Only version is reported. METHODS: 1,546 serum samples from 454 patients were assessed, collected at baseline and at 4 subsequent timepoints during treatment. A new predefined cut-off tested the ability to predict disease progression. A new measuring unit, DuA (DiviTum® unit of Activity) is adopted. RESULTS: A DiviTum®TKa score <250 DuA provides a much lower risk of progression within 30/60 days after blood draw, the negative predictive value (NPV) was 96.7% and 93.5%, respectively. Patients <250 DuA experienced significantly longer progression-free survival and overall survival, demonstrated at baseline and for all time intervals. CONCLUSIONS: DiviTum®TKa provides clinically meaningful information for patients with HR+ MBC. Low TKa levels provide such a high NPV for rapid progression that such patients might forego additional therapy added to single agent ET.Trial registration: NCT00075764.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores , Neoplasias de la Mama/patología , Pronóstico , Supervivencia sin Progresión , Receptor ErbB-2/uso terapéutico , Timidina Quinasa/uso terapéutico
2.
N Engl J Med ; 380(13): 1226-1234, 2019 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-30917258

RESUMEN

BACKGROUND: We previously reported prolonged progression-free survival and marginally prolonged overall survival among postmenopausal patients with hormone receptor-positive metastatic breast cancer who had been randomly assigned to receive the aromatase inhibitor anastrozole plus the selective estrogen-receptor down-regulator fulvestrant, as compared with anastrozole alone, as first-line therapy. We now report final survival outcomes. METHODS: We randomly assigned patients to receive either anastrozole or fulvestrant plus anastrozole. Randomization was stratified according to adjuvant tamoxifen use. Analysis of survival was performed by means of two-sided stratified log-rank tests and Cox regression. Efficacy and safety were compared between the two groups, both overall and in subgroups. RESULTS: Of 707 patients who had undergone randomization, 694 had data available for analysis. The combination-therapy group had 247 deaths among 349 women (71%) and a median overall survival of 49.8 months, as compared with 261 deaths among 345 women (76%) and a median overall survival of 42.0 months in the anastrozole-alone group, a significant difference (hazard ratio for death, 0.82; 95% confidence interval [CI], 0.69 to 0.98; P = 0.03 by the log-rank test). In a subgroup analysis of the two strata, overall survival among women who had not received tamoxifen previously was longer with the combination therapy than with anastrozole alone (median, 52.2 months and 40.3 months, respectively; hazard ratio, 0.73; 95% CI, 0.58 to 0.92); among women who had received tamoxifen previously, overall survival was similar in the two groups (median, 48.2 months and 43.5 months, respectively; hazard ratio, 0.97; 95% CI, 0.74 to 1.27) (P = 0.09 for interaction). The incidence of long-term toxic effects of grade 3 to 5 was similar in the two groups. Approximately 45% of the patients in the anastrozole-alone group crossed over to receive fulvestrant. CONCLUSIONS: The addition of fulvestrant to anastrozole was associated with increased long-term survival as compared with anastrozole alone, despite substantial crossover to fulvestrant after progression during therapy with anastrozole alone. The results suggest that the benefit was particularly notable in patients without previous exposure to adjuvant endocrine therapy. (Funded by the National Cancer Institute and AstraZeneca; ClinicalTrials.gov number, NCT00075764.).


Asunto(s)
Anastrozol/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de la Aromatasa/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Antagonistas del Receptor de Estrógeno/administración & dosificación , Fulvestrant/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Anastrozol/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Estudios Cruzados , Femenino , Estudios de Seguimiento , Fulvestrant/efectos adversos , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Metástasis de la Neoplasia/tratamiento farmacológico , Posmenopausia , Supervivencia sin Progresión
3.
J Exp Biol ; 224(11)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34109983

RESUMEN

Some species of durophagous moray eels (Muraenidae) have been documented emerging from the marine environment to capture intertidal crabs but how they consume prey out of water is unknown. Here, we trained snowflake morays, Echidna nebulosa, to undulate out of the aquatic environment to feed on land. On land, snowflake morays remove prey from the substrate by biting and swallow prey using pharyngeal jaw enabled transport. Although snowflake morays exhibit smaller jaw rotation angles on land when apprehending their prey, transport kinematics involving dorsoventral flexion of the head to protract the pharyngeal jaws and overall feeding times did not differ between terrestrial and aquatic treatments. We suggest that their elongate body plan, ability to rotate their heads in the dorsoventral and lateral directions, and extreme pharyngeal movements all contribute to the ability of durophagous morays to feed in the terrestrial environment.


Asunto(s)
Tachyglossidae , Animales , Fenómenos Biomecánicos , Anguilas , Conducta Alimentaria , Maxilares , Faringe , Conducta Predatoria
4.
Eur Radiol ; 31(4): 2559-2567, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33001309

RESUMEN

OBJECTIVES: To apply deep learning algorithms using a conventional convolutional neural network (CNN) and a recurrent CNN to differentiate three breast cancer molecular subtypes on MRI. METHODS: A total of 244 patients were analyzed, 99 in training dataset scanned at 1.5 T and 83 in testing-1 and 62 in testing-2 scanned at 3 T. Patients were classified into 3 subtypes based on hormonal receptor (HR) and HER2 receptor: (HR+/HER2-), HER2+, and triple negative (TN). Only images acquired in the DCE sequence were used in the analysis. The smallest bounding box covering tumor ROI was used as the input for deep learning to develop the model in the training dataset, by using a conventional CNN and the convolutional long short-term memory (CLSTM). Then, transfer learning was applied to re-tune the model using testing-1(2) and evaluated in testing-2(1). RESULTS: In the training dataset, the mean accuracy evaluated using tenfold cross-validation was higher by using CLSTM (0.91) than by using CNN (0.79). When the developed model was applied to the independent testing datasets, the accuracy was 0.4-0.5. With transfer learning by re-tuning parameters in testing-1, the mean accuracy reached 0.91 by CNN and 0.83 by CLSTM, and improved accuracy in testing-2 from 0.47 to 0.78 by CNN and from 0.39 to 0.74 by CLSTM. Overall, transfer learning could improve the classification accuracy by greater than 30%. CONCLUSIONS: The recurrent network using CLSTM could track changes in signal intensity during DCE acquisition, and achieved a higher accuracy compared with conventional CNN during training. For datasets acquired using different settings, transfer learning can be applied to re-tune the model and improve accuracy. KEY POINTS: • Deep learning can be applied to differentiate breast cancer molecular subtypes. • The recurrent neural network using CLSTM could track the change of signal intensity in DCE images, and achieved a higher accuracy compared with conventional CNN during training. • For datasets acquired using different scanners with different imaging protocols, transfer learning provided an efficient method to re-tune the classification model and improve accuracy.


Asunto(s)
Neoplasias de la Mama , Algoritmos , Neoplasias de la Mama/diagnóstico por imagen , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética , Redes Neurales de la Computación
5.
J Digit Imaging ; 34(4): 877-887, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34244879

RESUMEN

To develop a U-net deep learning method for breast tissue segmentation on fat-sat T1-weighted (T1W) MRI using transfer learning (TL) from a model developed for non-fat-sat images. The training dataset (N = 126) was imaged on a 1.5 T MR scanner, and the independent testing dataset (N = 40) was imaged on a 3 T scanner, both using fat-sat T1W pulse sequence. Pre-contrast images acquired in the dynamic-contrast-enhanced (DCE) MRI sequence were used for analysis. All patients had unilateral cancer, and the segmentation was performed using the contralateral normal breast. The ground truth of breast and fibroglandular tissue (FGT) segmentation was generated using a template-based segmentation method with a clustering algorithm. The deep learning segmentation was performed using U-net models trained with and without TL, by using initial values of trainable parameters taken from the previous model for non-fat-sat images. The ground truth of each case was used to evaluate the segmentation performance of the U-net models by calculating the dice similarity coefficient (DSC) and the overall accuracy based on all pixels. Pearson's correlation was used to evaluate the correlation of breast volume and FGT volume between the U-net prediction output and the ground truth. In the training dataset, the evaluation was performed using tenfold cross-validation, and the mean DSC with and without TL was 0.97 vs. 0.95 for breast and 0.86 vs. 0.80 for FGT. When the final model developed with and without TL from the training dataset was applied to the testing dataset, the mean DSC was 0.89 vs. 0.83 for breast and 0.81 vs. 0.81 for FGT, respectively. Application of TL not only improved the DSC, but also decreased the required training case number. Lastly, there was a high correlation (R2 > 0.90) for both the training and testing datasets between the U-net prediction output and ground truth for breast volume and FGT volume. U-net can be applied to perform breast tissue segmentation on fat-sat images, and TL is an efficient strategy to develop a specific model for each different dataset.


Asunto(s)
Densidad de la Mama , Procesamiento de Imagen Asistido por Computador , Mama/diagnóstico por imagen , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética
6.
Breast Cancer Res ; 22(1): 29, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32169100

RESUMEN

BACKGROUND: Breast cancer patients with early-stage disease are increasingly administered neoadjuvant chemotherapy (NAC) to downstage their tumors prior to surgery. In this setting, approximately 31% of patients fail to respond to therapy. This demonstrates the need for techniques capable of providing personalized feedback about treatment response at the earliest stages of therapy to identify patients likely to benefit from changing treatment. Diffuse optical spectroscopic imaging (DOSI) has emerged as a promising functional imaging technique for NAC monitoring. DOSI uses non-ionizing near-infrared light to provide non-invasive measures of absolute concentrations of tissue chromophores such as oxyhemoglobin. In 2011, we reported a new DOSI prognostic marker, oxyhemoglobin flare: a transient increase in oxyhemoglobin capable of discriminating NAC responders within the first day of treatment. In this follow-up study, DOSI was used to confirm the presence of the flare as well as to investigate whether DOSI markers of NAC response are regimen dependent. METHODS: This dual-center study examined 54 breast tumors receiving NAC measured with DOSI before therapy and the first week following chemotherapy administration. Patients were treated with either a standard of care maximum tolerated dose (MTD) regimen or an investigational metronomic (MET) regimen. Changes in tumor chromophores were tracked throughout the first week and compared to pathologic response and treatment regimen at specific days utilizing generalized estimating equations (GEE). RESULTS: Within patients receiving MTD therapy, the oxyhemoglobin flare was confirmed as a prognostic DOSI marker for response appearing as soon as day 1 with post hoc GEE analysis demonstrating a difference of 48.77% between responders and non-responders (p < 0.0001). Flare was not observed in patients receiving MET therapy. Within all responding patients, the specific treatment was a significant predictor of day 1 changes in oxyhemoglobin, showing a difference of 39.45% (p = 0.0010) between patients receiving MTD and MET regimens. CONCLUSIONS: DOSI optical biomarkers are differentially sensitive to MTD and MET regimens at early timepoints suggesting the specific treatment regimen should be considered in future DOSI studies. Additionally, DOSI may help to identify regimen-specific responses in a more personalized manner, potentially providing critical feedback necessary to implement adaptive changes to the treatment strategy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/patología , Hemodinámica/efectos de los fármacos , Terapia Neoadyuvante/métodos , Imagen Óptica/métodos , Espectroscopía Infrarroja Corta/métodos , Administración Metronómica , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Dosis Máxima Tolerada , Persona de Mediana Edad , Resultado del Tratamiento
7.
Syst Biol ; 67(1): 127-144, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28472434

RESUMEN

Adaptive radiation is hypothesized to be a primary mechanism that drives the remarkable species diversity and morphological disparity across the Tree of Life. Tests for adaptive radiation in extant taxa are traditionally estimated from calibrated molecular phylogenies with little input from extinct taxa. With 85 putative species in 33 genera and over 400 described extinct species, the carnivoran superfamily Musteloidea is a prime candidate to investigate patterns of adaptive radiation using both extant- and fossil-based macroevolutionary methods. The species diversity and equally impressive ecological and phenotypic diversity found across Musteloidea is often attributed to two adaptive radiations coinciding with two major climate events, the Eocene-Oligocene transition and the Mid-Miocene Climate Transition. Here, we compiled a novel time-scaled phylogeny for 88% of extant musteloids and used it as a framework for testing the predictions of adaptive radiation hypotheses with respect to rates of lineage diversification and phenotypic evolution. Contrary to expectations, we found no evidence for rapid bursts of lineage diversification at the origin of Musteloidea, and further analyses of lineage diversification rates using molecular and fossil-based methods did not find associations between rates of lineage diversification and the Eocene-Oligocene transition or Mid-Miocene Climate Transition as previously hypothesized. Rather, we found support for decoupled diversification dynamics driven by increased clade carrying capacity in the branches leading to a subclade of elongate mustelids. Supporting decoupled diversification dynamics between the subclade of elongate mustelids and the ancestral musteloid regime is our finding of increased rates of body length evolution, but not body mass evolution, within the decoupled mustelid subclade. The lack of correspondence in rates of body mass and length evolution suggest that phenotypic evolutionary rates under a single morphological metric, even one as influential as mass, may not capture the evolution of diversity in clades that exhibit elongate body shapes. The discordance in evolutionary rates between body length and body mass along with evidence of decoupled diversification dynamics suggests that body elongation might be an innovation for the exploitation of novel Mid-Miocene resources, resulting in the radiation of some musteloids.


Asunto(s)
Tamaño Corporal , Carnívoros/clasificación , Fósiles , Filogenia , Animales , Biodiversidad , Carnívoros/anatomía & histología , Carnívoros/genética , Especiación Genética
8.
J Exp Biol ; 222(Pt 5)2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30679244

RESUMEN

Animals use diverse feeding strategies to capture and consume prey, with many species switching between strategies to accommodate different prey. Many marine animals exhibit behavioral flexibility when feeding to deal with spatial and temporal heterogeneity in prey resources. However, little is known about flexibility in the feeding behavior of many large marine predators. Here, we documented the feeding behavior and kinematics of the endangered Hawaiian monk seal (Neomonachus schauinslandi, n=7) through controlled feeding trials. Seals were fed multiple prey types (e.g. night smelt, capelin, squid and herring) that varied in size and shape to examine behavioral flexibility in feeding. Hawaiian monk seals primarily used suction feeding (91% of all feeding trials) across all prey types, but biting, specifically pierce feeding, was also observed (9% of all feeding trials). Suction feeding was characterized by shorter temporal events, a smaller maximum gape and gape angle, and a fewer number of jaw motions than pierce feeding; suction feeding kinematic performance was also more variable compared with pierce feeding. Seals showed behavioral flexibility in their use of the two strategies. Suction feeding was used most frequently when targeting small to medium sized prey and biting was used with increasing frequency on larger prey. The feeding kinematics differed between feeding strategies and prey types, showing that Hawaiian monk seals adjusted their behaviors to particular feeding contexts. Hawaiian monk seals are opportunistic marine predators and their ability to adapt their feeding strategy and behavior to specific foraging scenarios allows them to target diverse prey resources.


Asunto(s)
Cadena Alimentaria , Conducta Predatoria , Phocidae/fisiología , Animales , Tamaño Corporal , Peces/fisiología , Hawaii , Phocidae/psicología
9.
Am Nat ; 191(5): E129-E143, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29693442

RESUMEN

Phenotypic convergence is a macroevolutionary pattern that need not be consistent across life history. Ontogenetic transitions in dietary specialization clearly illustrate the dynamics of ecological selection as organisms grow. The extent of phenotypic convergence among taxa that share a similar ecological niche may therefore vary ontogenetically. Because ontogenetic processes have been shown to evolve, phylogenetic comparative methods can be useful in examining how the scaling of traits relates to ecology. Cleaning, a behavior in which taxa consume ectoparasites off clientele, is well represented among wrasses (Labridae). Nearly three-fourths of labrids that clean do so predominately as juveniles, transitioning away as adults. We examine the scaling patterns of 33 labrid species to understand how life-history patterns of cleaning relate to ontogenetic patterns of phenotypic convergence. We find that as juveniles, cleaners exhibit convergence in body and cranial traits that enhance ectoparasitivory. We then find that taxa that transition away from cleaning exhibit ontogenetic trajectories that are distinct from those of other wrasses. Obligate and facultative species that continue to clean over ontogeny, however, maintain characteristics that are conducive to cleaning. Collectively, we find that life-history patterns of cleaning behavior are concordant with ontogenetic patterns in phenotype in wrasses.


Asunto(s)
Rasgos de la Historia de Vida , Perciformes/genética , Fenotipo , Filogenia , Animales , Biometría , Perciformes/crecimiento & desarrollo
10.
J Evol Biol ; 31(12): 1918-1931, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30270461

RESUMEN

Size and shape are often considered important variables that lead to variation in performance. In studies of feeding, size-corrected metrics of the skull are often used as proxies of biting performance; however, few studies have examined the relationship between cranial shape in its entirety and estimated bite force across species and how dietary ecologies may affect these variables differently. Here, we used geometric morphometric and phylogenetic comparative approaches to examine relationships between cranial morphology and estimated bite force in the carnivoran clade Musteloidea. We found a strong relationship between cranial size and estimated bite force but did not find a significant relationship between cranial shape and size-corrected estimated bite force. Many-to-one mapping of form to function may explain this pattern because a variety of evolutionary shape changes rather than a single shape change may have contributed to an increase in relative biting ability. We also found that dietary ecologies influenced cranial shape evolution but did not influence cranial size nor size-corrected bite force evolution. Although musteloids with different diets exhibit variation in cranial shapes, they have similar estimated bite forces suggesting that other feeding performance metrics and potentially nonfeeding traits are also important contributors to cranial evolution. We postulate that axial and appendicular adaptations and the interesting feeding behaviours reported for species within this group also facilitate different dietary ecologies between species. Future work integrating cranial, axial and appendicular form and function with behavioural observations will reveal further insights into the evolution of dietary ecologies and other ecological variables.


Asunto(s)
Fuerza de la Mordida , Dieta , Mustelidae/anatomía & histología , Mustelidae/fisiología , Cráneo/anatomía & histología , Animales , Femenino , Mustelidae/genética , Filogenia , Cráneo/fisiología
11.
J Exp Biol ; 221(Pt 15)2018 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-29895682

RESUMEN

Feeding kinematic studies inform our understanding of behavioral diversity and provide a framework for studying the flexibility and constraints of different prey acquisition strategies. However, little is known about the feeding behaviors used by many marine mammals. We characterized the feeding behaviors and associated kinematics of captive bearded (Erignathus barbatus), harbor (Phoca vitulina), ringed (Pusa hispida) and spotted (Phoca largha) seals through controlled feeding trials. All species primarily used a suction feeding strategy but were also observed using a biting strategy, specifically pierce feeding. Suction feeding was distinct from pierce feeding and was characterized by significantly faster feeding times, smaller gapes and gape angles, smaller gular depressions and fewer jaw motions. Most species showed higher variability in suction feeding performance than in pierce feeding, indicating that suction feeding is a behaviorally flexible strategy. Bearded seals were the only species for which there was strong correspondence between skull and dental morphology and feeding strategy, providing further support for their classification as suction feeding specialists. Harbor, ringed and spotted seals have been classified as pierce feeders based on skull and dental morphologies. Our behavioral and kinematic analyses show that suction feeding is also an important feeding strategy for these species, indicating that skull morphology alone does not capture the true diversity of feeding behaviors used by pinnipeds. The ability of all four species to use more than one feeding strategy is likely advantageous for foraging in spatially and temporally dynamic marine ecosystems that favor opportunistic predators.


Asunto(s)
Conducta Alimentaria/fisiología , Phocidae/anatomía & histología , Phocidae/fisiología , Cráneo/anatomía & histología , Animales , Fenómenos Biomecánicos , Femenino , Masculino , Boca/anatomía & histología , Conducta Predatoria , Análisis de Componente Principal
12.
Oecologia ; 188(3): 875-887, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30229354

RESUMEN

Despite the importance of predation in many ecosystems, gaps remain in our understanding of nocturnal marine predators. Although the kelp forests of Southern California are some of the most well-studied ecosystems, California morays, Gymnothorax mordax, are predominately nocturnal predators that have remained largely unstudied and their predatory effects on the kelp forest ecosystem are unknown. We use a multi-year data set to examine the dietary breadth of G. mordax and to determine the functional role of this predator. We also quantify bite force to examine the potential performance limitations of morays in exploiting prey. Stomach content analyses and linear selectivity index values indicate that G. mordax specializes on kelp bass, Paralabrax clathratus. Average size of kelp bass consumed varies across years, suggesting that morays respond to fluctuations in prey size availability. The scaling relationship of kelp bass standard length and moray head length reveals an ontogenetic shift, where maximum prey size increases with moray size and small prey are dropped from the diet of larger individuals. Moray bite force exhibited strong positive allometry with moray head size, suggesting that larger morays exhibit greater bite forces for their head and body size. However, we found no relationship between prey size and bite force, suggesting that a disproportional increase in bite force does not facilitate the consumption of disproportionately larger prey. Our results indicate that while G. mordax of Catalina Island is a dietary specialist, it is capable of exhibiting functional shifts in prey size and species based on their abundance.


Asunto(s)
Lubina , Kelp , Animales , California , Ecosistema , Anguilas , Islas , Conducta Predatoria
13.
Ann Surg Oncol ; 24(7): 1853-1860, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27864694

RESUMEN

BACKGROUND: NRG Oncology/NSABP trial B-40 tested the impact of adding bevacizumab (bev) to neoadjuvant chemotherapy for operable breast cancer. Secondary endpoints included rates of surgical complications after surgery in patients who did or did not receive bev. METHODS: A total of 1206 women with HER2-negative operable breast cancer were randomly assigned to receive one of three different docetaxel-plus-anthracycline-based regimens, without or with bev (15 mg/kg every 3 weeks) for the first 6 of 8 cycles and for 10 doses postoperatively. Surgical complications were assessed from date of surgery through 24 months following study entry. RESULTS: Early surgical complications were significantly more frequent in the bev group (25.4 vs. 18.9%; trend test p = 0.008), but most were grade 1-2. Early noninfectious wound dehiscences were infrequent and not significantly different (5.4 vs. 3.1%; trend test p = 0.15). Long-term noninfectious wound complications were significantly higher for patients receiving bev (11.8 vs. 5.1%; trend test p = 0.0007), but the incidence of grade ≥3 wound dehiscence was low in both groups (<1%). Among 193 patients undergoing expander or implant reconstructions, 19 (19.6%) of 97 in the bev-receiving group versus 10 (10.4%) of 96 in the non-bev group had grade ≥3 complications (Pearson, p = 0.11). CONCLUSIONS: Overall, adding bev increased surgical complications, but most serious complications were not significantly increased. In particular, the need for surgical intervention in patients undergoing breast reconstruction with prosthetic implants was higher with bev but was not statistically significantly different. With precautions, bev can be used safely perioperatively in patients undergoing surgery for breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/cirugía , Mastectomía/efectos adversos , Infección de la Herida Quirúrgica/etiología , Antraciclinas/administración & dosificación , Bevacizumab/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Terapia Combinada , Docetaxel , Femenino , Estudios de Seguimiento , Humanos , Mamoplastia/efectos adversos , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Taxoides/administración & dosificación
14.
J Exp Biol ; 220(Pt 15): 2787-2797, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28515238

RESUMEN

Cleaning, a dietary strategy in which mucus or ectoparasites are removed and consumed off other taxa, is performed facultatively or obligately in a variety of species. We explored whether species in the Labridae (wrasses, parrotfishes) of varying ecological specialization employ similar mechanisms of prey capture. In investigating feeding on attached prey among juveniles of 19 species of wrasses, we found that patterns of biting in wrasses are influenced by the interaction between the maxilla and a feature of the premaxilla which we term the maxillary crest. Premaxillary motion during biting appears to be guided by the relative size of the crest. In many cases, this results in a 'premaxillary bite' wherein the premaxillae rapidly move anteroventrally to meet the lower jaws and deliver a protruded bite. Cleaners in the Labrichthyini tribe, however, exhibited reduced or absent maxillary crests. This coincided with a distinct kinematic pattern of prey capture in these labrichthyine cleaners, coupled with some of the fastest and lowest-excursion jaw movements. Although evidence of kinematic specialization can be found in these labrichthyines (most notably in the obligate cleaners in Labroides), we found that facultative cleaners from other lineages similarly evolved reductions in excursions and timing. Convergence in feeding kinematics is thus apparent despite varying degrees of cleaning specialization and underlying morphological features.


Asunto(s)
Fuerza de la Mordida , Maxilares/anatomía & histología , Perciformes/anatomía & histología , Perciformes/fisiología , Conducta Predatoria , Factores de Edad , Animales , Fenómenos Biomecánicos , Perciformes/crecimiento & desarrollo
15.
Br J Clin Pharmacol ; 81(6): 1134-41, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26859101

RESUMEN

AIMS: In the SWOG S0226 trial the combination of anastrozole plus fulvestrant (n = 349) was superior to anastrozole alone (n = 345) in hormone receptor (HR)-positive metastatic breast cancer. Here we report a pharmacokinetic subset analysis investigating a possible drug interaction between anastrozole and fulvestrant. METHODS: Post-menopausal patients with HR-positive metastatic breast cancer were randomized to anastrozole with or without concurrent fulvestrant. Blood samples were collected at 2, 4, 6 and 8 months, just prior to receiving the next dose of anastrozole and fulvestrant. Drug concentrations were measured via LC/MS-MS. Anastrozole concentration was compared in patients on anastrozole alone vs. patients on concomitant fulvestrant. Comparisons were made at each time point using parametric tests and over time using a linear mixed effects model. RESULTS: A total of 483 anastrozole concentration measurements were included, 224 samples from 64 patients on the anastrozole alone arm and 259 from 73 patients on the combination arm. The mean anastrozole concentration in the combination arm was significantly lower than that in the anastrozole alone arm at each sample collection time (all P < 0.01) and in the mixed effects model (an estimated difference of 9.85 ng ml(-1) (95% CI 5.69, 14.00 ng ml(-1) ), P < 0.001). CONCLUSION: A significant pharmacokinetic drug interaction was detected, in which the addition of fulvestrant to anastrozole treatment decreased the trough anastrozole concentration. Further research is needed to verify whether this interaction affects treatment efficacy and to determine the pharmacological mechanism by which this interaction occurs.


Asunto(s)
Neoplasias de la Mama/metabolismo , Estradiol/análogos & derivados , Nitrilos/farmacocinética , Triazoles/farmacocinética , Anastrozol , Neoplasias de la Mama/sangre , Neoplasias de la Mama/tratamiento farmacológico , Interacciones Farmacológicas , Estradiol/farmacología , Femenino , Fulvestrant , Humanos , Nitrilos/sangre , Triazoles/sangre
16.
Lancet Oncol ; 16(9): 1037-1048, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26272770

RESUMEN

BACKGROUND: NSABP B-40 was a 3 × 2 factorial trial testing whether adding capecitabine or gemcitabine to docetaxel followed by doxorubicin plus cyclophosphamide neoadjuvant chemotherapy would improve outcomes in women with operable, HER2-negative breast cancer and whether adding neoadjuvant plus adjuvant bevacizumab to neoadjuvant chemotherapy regimens would also improve outcomes. As reported previously, addition of neoadjuvant bevacizumab increased the proportion of patients achieving a pathological complete response, which was the primary endpoint. We present secondary patient outcomes, including disease-free survival, a specified endpoint by protocol, and data for distant recurrence-free interval, and overall survival, which were not prespecified endpoints but were collected prospectively. METHODS: In this randomised controlled trial (NSABP B-40), we enrolled women aged 18 years or older, with operable, HER2-non-amplified invasive adenocarcinoma of the breast, 2 cm or greater in diameter by palpation, clinical stage T1c-3, cN0, cN1, or cN2a, without metastatic disease and diagnosed by core needle biopsy. Patients received one of three docetaxel-based neoadjuvant regimens for four cycles: docetaxel alone (100 mg/m(2)) with addition of capecitabine (825 mg/m(2) oral twice daily days 1-14, 75 mg/m(2) docetaxel) or with addition of gemcitabine (1000 mg/m(2) days 1 and 8 intravenously, 75 mg/m(2) docetaxel), all followed by neoadjuvant doxorubicin and cyclophosphamide (60 mg/m(2) and 600 mg/m(2) intravenously) every 3 weeks for four cycles. Those randomly assigned to bevacizumab groups were to receive bevacizumab (15 mg/kg, every 3 weeks for six cycles) with neoadjuvant chemotherapy and postoperatively for ten doses. Randomisation was done (1:1:1:1:1:1) via a biased-coin minimisation procedure to balance the characteristics with respect to clinical nodal status, clinical tumour size, hormone receptor status, and age. Intent-to-treat analyses were done for disease-free survival and overall survival. This study is registered with ClinicalTrials.gov, number NCT00408408. FINDINGS: Between Jan 5, 2007, and June 30, 2010, 1206 patients were enrolled in the study. Follow-up data were collected from Oct 31, 2007 to March 27, 2014, and were available for overall survival in 1186 patients, disease-free survival in 1184, and distant recurrence-free interval in 1181. Neither capecitabine nor gemcitabine increased disease-free survival or overall survival. Median follow-up was 4·7 years (IQR 4·0-5·2). The addition of bevacizumab significantly increased overall survival (hazard ratio 0·65 [95% CI 0·49-0·88]; p=0·004) but did not significantly increase disease-free survival (0·80 [0·63-1·01]; p=0·06). Four deaths occurred on treatment due to vascular disorder (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), sudden death (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), infective endocarditis (docetaxel plus bevacizumab followed by doxorubicin plus cyclophosphamide and bevacizumab group), and visceral arterial ischaemia (docetaxel followed by doxorubicin plus cyclophosphamide group). The most common grade 3-4 adverse events in the bevacizumab group were neutropenia (grade 3, 99 [17%]; grade 4, 37 [6%]), hand-foot syndrome (grade 3, 63 [11%]), and hypertension (grade 3, 60 [10%]; grade 4, two [<1%]) and in the non-bevacizumab group were neutropenia (grade 3, 98 [16%]; grade 4, 36 [6%]), fatigue (grade 3, 53 [9%]), and hand-foot syndrome (grade 3, 43 [7%]). INTERPRETATION: The addition of gemcitabine or capecitabine to neoadjuvant docetaxel plus doxorubicin plus cyclophosphamide does not seem to provide any benefit to patients with operable breast cancer, and should not change clinical practice in the short term. The improved overall survival with bevacizumab contradicts the findings of other studies of bevacizumab in breast cancer and may indicate the need for additional investigation of this agent. FUNDING: National Institutes of Health, Genentech, Roche Laboratories, Lilly Research Laboratories, and Precision Therapeutics.


Asunto(s)
Bevacizumab/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Neoplasias de la Mama/patología , Capecitabina/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Docetaxel , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Taxoides/administración & dosificación , Estados Unidos , Gemcitabina
17.
N Engl J Med ; 367(5): 435-44, 2012 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-22853014

RESUMEN

BACKGROUND: The aromatase inhibitor anastrozole inhibits estrogen synthesis. Fulvestrant binds and accelerates degradation of estrogen receptors. We hypothesized that these two agents in combination might be more effective than anastrozole alone in patients with hormone-receptor (HR)-positive metastatic breast cancer. METHODS: Postmenopausal women with previously untreated metastatic disease were randomly assigned, in a 1:1 ratio, to receive either 1 mg of anastrozole orally every day (group 1), with crossover to fulvestrant alone strongly encouraged if the disease progressed, or anastrozole and fulvestrant in combination (group 2). Patients were stratified according to prior or no prior receipt of adjuvant tamoxifen therapy. Fulvestrant was administered intramuscularly at a dose of 500 mg on day 1 and 250 mg on days 14 and 28 and monthly thereafter. The primary end point was progression-free survival, with overall survival designated as a prespecified secondary outcome. RESULTS: The median progression-free survival was 13.5 months in group 1 and 15.0 months in group 2 (hazard ratio for progression or death with combination therapy, 0.80; 95% confidence interval [CI], 0.68 to 0.94; P=0.007 by the log-rank test). The combination therapy was generally more effective than anastrozole alone in all subgroups, with no significant interactions. Overall survival was also longer with combination therapy (median, 41.3 months in group 1 and 47.7 months in group 2; hazard ratio for death, 0.81; 95% CI, 0.65 to 1.00; P=0.05 by the log-rank test), despite the fact that 41% of the patients in group 1 crossed over to fulvestrant after progression. Three deaths that were possibly associated with treatment occurred in group 2. The rates of grade 3 to 5 toxic effects did not differ significantly between the two groups. CONCLUSIONS: The combination of anastrozole and fulvestrant was superior to anastrozole alone or sequential anastrozole and fulvestrant for the treatment of HR-positive metastatic breast cancer, despite the use of a dose of fulvestrant that was below the current standard. (Funded by the National Cancer Institute and AstraZeneca; SWOG ClinicalTrials.gov number, NCT00075764.).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Estradiol/análogos & derivados , Nitrilos/administración & dosificación , Triazoles/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Anastrozol , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Estudios Cruzados , Supervivencia sin Enfermedad , Estradiol/administración & dosificación , Estradiol/efectos adversos , Antagonistas de Estrógenos/administración & dosificación , Antagonistas de Estrógenos/efectos adversos , Femenino , Fulvestrant , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Metástasis de la Neoplasia , Nitrilos/efectos adversos , Posmenopausia , Triazoles/efectos adversos
18.
N Engl J Med ; 366(4): 310-20, 2012 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-22276821

RESUMEN

BACKGROUND: Bevacizumab and the antimetabolites capecitabine and gemcitabine have been shown to improve outcomes when added to taxanes in patients with metastatic breast cancer. The primary aims of this trial were to determine whether the addition of capecitabine or gemcitabine to neoadjuvant chemotherapy with docetaxel, followed by doxorubicin plus cyclophosphamide, would increase the rates of pathological complete response in the breast in women with operable, human epidermal growth factor receptor 2 (HER2)-negative breast cancer and whether adding bevacizumab to these chemotherapy regimens would increase the rates of pathological complete response. METHODS: We randomly assigned 1206 patients to receive neoadjuvant therapy consisting of docetaxel (100 mg per square meter of body-surface area on day 1), docetaxel (75 mg per square meter on day 1) plus capecitabine (825 mg per square meter twice a day on days 1 to 14), or docetaxel (75 mg per square meter on day 1) plus gemcitabine (1000 mg per square meter on days 1 and 8) for four cycles, with all regimens followed by treatment with doxorubicin-cyclophosphamide for four cycles. Patients were also randomly assigned to receive or not to receive bevacizumab (15 mg per kilogram of body weight) for the first six cycles of chemotherapy. RESULTS: The addition of capecitabine or gemcitabine to docetaxel therapy, as compared with docetaxel therapy alone, did not significantly increase the rate of pathological complete response (29.7% and 31.8%, respectively, vs. 32.7%; P=0.69). Both capecitabine and gemcitabine were associated with increased toxic effects--specifically, the hand-foot syndrome, mucositis, and neutropenia. The addition of bevacizumab significantly increased the rate of pathological complete response (28.2% without bevacizumab vs. 34.5% with bevacizumab, P=0.02). The effect of bevacizumab on the rate of pathological complete response was not the same in the hormone-receptor-positive and hormone-receptor-negative subgroups. The addition of bevacizumab increased the rates of hypertension, left ventricular systolic dysfunction, the hand-foot syndrome, and mucositis. CONCLUSIONS: The addition of bevacizumab to neoadjuvant chemotherapy significantly increased the rate of pathological complete response, which was the primary end point of this study. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00408408.).


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Receptor ErbB-2 , Adulto , Anciano , Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Capecitabina , Ciclofosfamida/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Progresión de la Enfermedad , Docetaxel , Doxorrubicina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/análogos & derivados , Humanos , Modelos Logísticos , Mastectomía Segmentaria , Persona de Mediana Edad , Terapia Neoadyuvante , Taxoides/administración & dosificación , Resultado del Tratamiento , Gemcitabina
19.
Am Nat ; 183(6): E168-84, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24823828

RESUMEN

Convergence is central to the study of evolution because it demonstrates the power of natural selection to deterministically shape phenotypic diversity. However, the conditions under which a common morphology repeatedly evolves may be restrictive. Many factors, such as differing genetic and environmental backgrounds and many-to-one mapping of form to function, contribute to variability in responses to selection. Nevertheless, lineages may evolve similar, even if not identical, forms given a shared selective regime, providing opportunities to examine the relative importance of natural selection, constraint, and contingency. Here, we show that following 10 transitions to durophagy (eating hard-shelled prey) in moray eels (Muraenidae), cranial morphology repeatedly evolved toward a novel region of morphological space indicative of enhanced feeding performance on hard prey. Disparity among the resulting 15 durophagous species, however, is greater than disparity among ancestors that fed on large evasive prey, contradicting the pattern expected under convergence. This elevated disparity is a consequence of lineage-specific responses to durophagy, in which independent transitions vary in the suites of traits exhibiting the largest changes. Our results reveal a pattern of imperfect convergence, which suggests shared selection may actually promote diversification because lineages often differ in their phenotypic responses to similar selective demands.


Asunto(s)
Evolución Biológica , Anguilas/anatomía & histología , Maxilares/anatomía & histología , Cráneo/anatomía & histología , Animales , Fenómenos Biomecánicos , Conducta Alimentaria , Filogenia
20.
J Exp Biol ; 217(Pt 20): 3597-606, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25189367

RESUMEN

In fishes, cleaning is a mutualistic behavior wherein a species will remove and consume ectoparasites from other organisms. More than two-thirds of cleaner fishes display this behavior predominately as juveniles and discontinue cleaning as adults; such species are here referred to as 'facultative cleaners'. Whether allometric changes in morphological traits coincide with ontogenetic shifts away from cleaning is unknown. We tested the hypothesis that transitions away from cleaning are associated with scaling patterns in the feeding apparatus of facultative cleaners, and then compared such patterns with those exhibited by non-cleaner congeners. We measured functional traits related to feeding, such as vertical gape distance, premaxillary protrusion distance and maxillary kinematic transmission coefficient (KT) in each ontogenetic series of 11 Thalassoma wrasses (Labridae). As these fishes predominately capture prey via biting, we modeled bite force using MandibLever (v3.3) to create an ontogenetic trajectory of bite force for each species. Our results indicate that cleaner fishes in Thalassoma, as juveniles, possess jaws with low mobility that exhibit weaker bite forces. Additionally, there was remarkable consistency in the range of body lengths over which we observed significant differences between facultative cleaners and non-cleaners in bite force, vertical gape distance and premaxillary protrusion distance. Through ontogeny, facultative cleaner fishes exhibit positive allometry for a number of functionally important feeding traits, which possibly obviates the need to continue cleaning.


Asunto(s)
Fuerza de la Mordida , Conducta Alimentaria/fisiología , Perciformes/anatomía & histología , Perciformes/crecimiento & desarrollo , Animales , Maxilares/anatomía & histología , Simbiosis
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