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1.
Gynecol Oncol ; 185: 194-201, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38452634

RESUMEN

OBJECTIVE: Endometrial cancer (EndoCA) is the most common gynecologic cancer and incidence and mortality rate continue to increase. Despite well-characterized knowledge of EndoCA-defining mutations, no effective diagnostic or screening tests exist. To lay the foundation for testing development, our study focused on defining the prevalence of somatic mutations present in non-cancerous uterine tissue. METHODS: We obtained ≥8 uterine samplings, including separate endometrial and myometrial layers, from each of 22 women undergoing hysterectomy for non-cancer conditions. We ultra-deep sequenced (>2000× coverage) samples using a 125 cancer-relevant gene panel. RESULTS: All women harbored complex mutation patterns. In total, 308 somatic mutations were identified with mutant allele frequencies ranging up to 96.0%. These encompassed 56 unique mutations from 24 genes. The majority of samples possessed predicted functional cancer mutations but curiously no growth advantage over non-functional mutations was detected. Functional mutations were enriched with increasing patient age (p = 0.045) and BMI (p = 0.0007) and in endometrial versus myometrial layers (68% vs 39%, p = 0.0002). Finally, while the somatic mutation landscape shared similar mutation prevalence in key TCGA-defined EndoCA genes, notably PIK3CA, significant differences were identified, including NOTCH1 (77% vs 10%), PTEN (9% vs 61%), TP53 (0% vs 37%) and CTNNB1 (0% vs 26%). CONCLUSIONS: An important caveat for future liquid biopsy/DNA-based cancer diagnostics is the repertoire of shared and distinct mutation profiles between histologically unremarkable and EndoCA tissues. The lack of selection pressure between functional and non-functional mutations in histologically unremarkable uterine tissue may offer a glimpse into an unrecognized EndoCA protective mechanism.


Asunto(s)
Endometrio , Mutación , Humanos , Femenino , Persona de Mediana Edad , Endometrio/patología , Endometrio/metabolismo , Anciano , Neoplasias Endometriales/genética , Neoplasias Endometriales/patología , Adulto , Secuenciación de Nucleótidos de Alto Rendimiento
2.
Glob Chang Biol ; 28(22): 6586-6601, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35978484

RESUMEN

Projecting the future distributions of commercially and ecologically important species has become a critical approach for ecosystem managers to strategically anticipate change, but large uncertainties in projections limit climate adaptation planning. Although distribution projections are primarily used to understand the scope of potential change-rather than accurately predict specific outcomes-it is nonetheless essential to understand where and why projections can give implausible results and to identify which processes contribute to uncertainty. Here, we use a series of simulated species distributions, an ensemble of 252 species distribution models, and an ensemble of three regional ocean climate projections, to isolate the influences of uncertainty from earth system model spread and from ecological modeling. The simulations encompass marine species with different functional traits and ecological preferences to more broadly address resource manager and fishery stakeholder needs, and provide a simulated true state with which to evaluate projections. We present our results relative to the degree of environmental extrapolation from historical conditions, which helps facilitate interpretation by ecological modelers working in diverse systems. We found uncertainty associated with species distribution models can exceed uncertainty generated from diverging earth system models (up to 70% of total uncertainty by 2100), and that this result was consistent across species traits. Species distribution model uncertainty increased through time and was primarily related to the degree to which models extrapolated into novel environmental conditions but moderated by how well models captured the underlying dynamics driving species distributions. The predictive power of simulated species distribution models remained relatively high in the first 30 years of projections, in alignment with the time period in which stakeholders make strategic decisions based on climate information. By understanding sources of uncertainty, and how they change at different forecast horizons, we provide recommendations for projecting species distribution models under global climate change.


Asunto(s)
Cambio Climático , Ecosistema , Explotaciones Pesqueras , Predicción , Incertidumbre
3.
Mol Ecol ; 30(9): 1993-2008, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33645853

RESUMEN

Understanding the genomic basis of adaptation is critical for understanding evolutionary processes and predicting how species will respond to environmental change. Spinner dolphins in the eastern tropical Pacific (ETP) present a unique system for studying adaptation. Within this large geographical region are four spinner dolphin ecotypes with weak neutral genetic divergence and no obvious barriers to gene flow, but strong spatial variation in morphology, behaviour and habitat. These ecotypes have large population sizes, which could reduce the effects of drift and facilitate selection. To identify genomic regions putatively under divergent selective pressures between ecotypes, we used genome scans with 8994 RADseq single nucleotide polymorphisms (SNPs) to identify population differentiation outliers and genotype-environment association outliers. Gene ontology enrichment analyses indicated that outlier SNPs from both types of analyses were associated with multiple genes involved in social behaviour and hippocampus development, including 15 genes associated with the human social disorder autism. Evidence for divergent selection on social behaviour is supported by previous evidence that these spinner dolphin ecotypes differ in mating systems and associated social behaviours. In particular, three of the ETP ecotypes probably have a polygynous mating system characterized by strong premating competition among males, whereas the fourth ecotype probably has a polygynandrous mating system characterized by strong postmating competition such as sperm competition. Our results provide evidence that selection for social behaviour may be an evolutionary force driving diversification of spinner dolphins in the ETP, potentially as a result of divergent sexual selection associated with different mating systems. Future studies should further investigate the potential adaptive role of the candidate genes identified here, and could probably find further signatures of selection using whole genome sequence data.


Asunto(s)
Ecotipo , Stenella , Animales , Flujo Génico , Genética de Población , Genómica , Polimorfismo de Nucleótido Simple , Selección Genética , Conducta Social
4.
Phys Rev Lett ; 115(5): 052001, 2015 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-26274412

RESUMEN

We determine the dominant missing standard model (SM) contribution to the top quark pair forward-backward asymmetry at the Tevatron. Contrary to past expectations, we find a large, around 27%, shift relative to the well-known value of the inclusive asymmetry in next-to-leading order QCD. Combining all known standard model corrections, we find that A(FB)(SM)=0.095±0.007. This value is in agreement with the latest DØ measurement [V. M. Abazov et al. (D0 Collaboration), Phys. Rev. D 90, 072011 (2014)] A(FB)(D∅)=0.106±0.03 and about 1.5σ below that of CDF [T. Aaltonen et al. (CDF Collaboration), Phys. Rev. D 87, 092002 (2013)] A(FB)(CDF)=0.164±0.047. Our result is derived from a fully differential calculation of the next-to-next-to leading order (NNLO) QCD corrections to inclusive top pair production at hadron colliders and includes-without any approximation-all partonic channels contributing to this process. This is the first complete fully differential calculation in NNLO QCD of a two-to-two scattering process with all colored partons.

5.
Sci Rep ; 14(1): 17127, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054335

RESUMEN

People increasingly use large language model (LLM)-based conversational agents to obtain information. However, the information these models provide is not always factually accurate. Thus, it is critical to understand what helps users adequately assess the credibility of the provided information. Here, we report the results of two preregistered experiments in which participants rated the credibility of accurate versus partially inaccurate information ostensibly provided by a dynamic text-based LLM-powered agent, a voice-based agent, or a static text-based online encyclopedia. We found that people were better at detecting inaccuracies when identical information was provided as static text compared to both types of conversational agents, regardless of whether information search applications were branded (ChatGPT, Alexa, and Wikipedia) or unbranded. Mediation analysis overall corroborated the interpretation that a conversational nature poses a threat to adequate credibility judgments. Our research highlights the importance of presentation mode when dealing with misinformation.


Asunto(s)
Comunicación , Juicio , Humanos , Masculino , Femenino , Adulto , Lenguaje , Adulto Joven
6.
Phys Rev Lett ; 110(25): 252004, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23829732

RESUMEN

We compute the next-to-next-to-leading order (NNLO) quantum chromodynamics (QCD) correction to the total cross section for the reaction gg → tt + X. Together with the partonic channels we computed previously, the result derived in this Letter completes the set of NNLO QCD corrections to the total top pair-production cross section at hadron colliders. Supplementing the fixed order results with soft-gluon resummation with next-to-next-to-leading logarithmic accuracy, we estimate that the theoretical uncertainty of this observable due to unknown higher order corrections is about 3% at the LHC and 2.2% at the Tevatron. We observe a good agreement between the standard model predictions and the available experimental measurements. The very high theoretical precision of this observable allows a new level of scrutiny in parton distribution functions and new physics searches.

7.
Conn Med ; 77(6): 339-42, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23923251

RESUMEN

Schistosomiasis remains a major health threat in many resource-poor countries and is being seen with increasing frequency in developed countries among immigrants and tourists who have a history of freshwater exposure in endemic areas. We report a case ofa 56-year-old male with no significant past medical history, who presented for a routine screening colonoscopy, which revealed two polyps in the cecum, and multiple petechiae in the rectum. Histologic evaluation showed presence of Schistosoma mansoni eggs. One of the polyps, where eggs were also present, was diagnosed as neuroma/ Schwann cell hamartoma. This is the first reported casewhere colonic schistosomiasis is associatedwith cecal neuroma.


Asunto(s)
Neoplasias del Ciego/complicaciones , Ciego/patología , Neuroma/complicaciones , Esquistosomiasis mansoni/complicaciones , Animales , Biopsia , Neoplasias del Ciego/diagnóstico , Ciego/parasitología , Colonoscopía , Diagnóstico Diferencial , Heces/parasitología , Humanos , Masculino , Persona de Mediana Edad , Neuroma/diagnóstico , Recuento de Huevos de Parásitos , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis mansoni/diagnóstico , Esquistosomiasis mansoni/parasitología
8.
Conn Med ; 76(7): 401-4, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23248863

RESUMEN

We report the case of a 35-year-old male presenting with a steadily growing, painful left-cervical neck mass. Final histopathologic diagnosis was consistent with a thrombosed cavernous hemangioma arising in cervical ectopic thymus tissue. This is the first description, to our knowledge, of such an entity.


Asunto(s)
Coristoma/diagnóstico , Neoplasias de Cabeza y Cuello/diagnóstico , Hemangioma Cavernoso/diagnóstico , Trombosis/diagnóstico , Timo , Adulto , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Masculino
9.
J Clin Gastroenterol ; 45(4): 314-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20921901

RESUMEN

Eosinophilic myenteric ganglionitis is a disorder characterized by infiltration of the Auerbach plexus by eosinophils. It can be associated with a bowel dysmotility and a few cases of intestinal pseudo-obstructive syndrome have been described in children. In this case report, we present an elderly 93-year-old woman who presented with episodes of functional bowel obstruction of unknown etiology. After several admissions for recurrent obstipation requiring fecal disimpaction, she had a Hartmann procedure performed with a resection of the sigmoid colon. The sigmoid colon was markedly dilated and the only significant finding on histology was infiltration of the Auerbach plexus by eosinophils. The mucosa and the muscular layers appeared unremarkable. Her symptoms resolved after the resection and the patient is currently well after 5 months. Recurrent gastrointestinal pseudo-obstruction can arise secondary to eosinophilic myenteric ganglionitis even in adults. Clinical improvement is likely if this disease entity is promptly recognized and treated.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/complicaciones , Eosinofilia/complicaciones , Seudoobstrucción Intestinal/etiología , Plexo Mientérico/patología , Anciano , Enfermedades del Sistema Nervioso Autónomo/patología , Colon Sigmoide/patología , Colon Sigmoide/cirugía , Eosinofilia/patología , Femenino , Humanos , Seudoobstrucción Intestinal/diagnóstico , Seudoobstrucción Intestinal/cirugía
10.
Conn Med ; 75(10): 607-12, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22216676

RESUMEN

Retroperitoneal fibrosis is the presence of a fibrotic plaque in the prelumbar or presacral area. It can occur as a result of certain medications, fluid collections, inflammatory disease of various intra-abdominal organs, previous surgery or radiation therapy and various metastatic neoplasms. Most cases of retroperitoneal fibrosis are considered idiopathic. We report an interesting case of idiopathic retroperitoneal fibrosis with the emphasis on the importance of pathology to establish the diagnosis.


Asunto(s)
Fibrosis Retroperitoneal/etiología , Fibrosis Retroperitoneal/patología , Dolor Abdominal/etiología , Dolor Abdominal/patología , Linfocitos B/patología , Biopsia , Calcinosis/etiología , Calcinosis/patología , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Células Plasmáticas/patología , Linfocitos T/patología , Tomografía Computarizada por Rayos X
11.
PLoS One ; 15(11): e0235372, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33253179

RESUMEN

Lyme disease patients would greatly benefit from a timely, sensitive, and specific molecular diagnostic test that can detect the causal agent Borrelia burgdorferi at the onset of symptoms. Currently available diagnostic methods recommended by the Centers for Disease Control and Prevention for Lyme disease involve indirect serological tests that rely on the detection of a host-antibody response, which often takes more than three weeks to develop. With this process, many positive cases are not detected within a timely manner, preventing a complete cure. In this study, we have developed a digital polymerase chain reaction (PCR) assay that detects Lyme disease on clinical presentation with a sensitivity two-fold higher than that of the currently available diagnostic methods, using a cohort of patient samples collected from the Lyme disease endemic state of Connecticut, USA, in 2016-2018. Digital PCR technology was chosen as it is more advanced and sensitive than other PCR techniques in detecting rare targets. The analytical detection sensitivity of this diagnostic assay is approximately three genome copies of B. burgdorferi. The paucity of spirochetes in the bloodstream of Lyme disease patients has hindered the clinical adoption of PCR-based diagnostic tests. However, this drawback was overcome by using a comparatively larger sample volume, applying pre-analytical processing to the blood samples, and implementing a pre-amplification step to enrich for B. burgdorferi-specific gene targets before the patient samples are analyzed via digital PCR technology. Pre-analytical processing of blood samples from acute patients revealed that the best sample type for Lyme disease detection is platelet-rich plasma rather than whole blood. If detected in a timely manner, Lyme disease can be completely cured, thus limiting antibiotic overuse and associated morbidities.


Asunto(s)
Borrelia burgdorferi/genética , ADN Bacteriano/sangre , Enfermedad de Lyme/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Pruebas Serológicas/métodos , Borrelia burgdorferi/aislamiento & purificación , ADN Bacteriano/genética , Humanos , Enfermedad de Lyme/sangre , Enfermedad de Lyme/epidemiología
12.
Sci Adv ; 3(10): e1701140, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-29057322

RESUMEN

Climate variability alters nitrogen cycling, primary productivity, and dissolved oxygen concentration in marine ecosystems. We examined the role of this variability (as measured by six variables) on food chain length (FCL) in the California Current (CC) by reconstructing a time series of amino acid-specific δ15N values derived from common dolphins, an apex pelagic predator, and using two FCL proxies. Strong declines in FCL were observed after the 1997-1999 El Niño Southern Oscillation (ENSO) event. Bayesian models revealed longer FCLs under intermediate conditions for surface temperature, chlorophyll concentration, multivariate ENSO index, and total plankton volume but not for hypoxic depth and nitrate concentration. Our results challenge the prevalent paradigm that suggested long-term stability in the food web structure in the CC and, instead, reveal that pelagic food webs respond strongly to disturbances associated with ENSO events, local oceanography, and ongoing changes in climate.


Asunto(s)
Ambiente , Cadena Alimentaria , Aminoácidos , California , Ecosistema , Geografía , Nitrógeno , Isótopos de Nitrógeno
13.
Am Surg ; 72(12): 1210-1, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17216820

RESUMEN

The use of prosthetic mesh is the current acceptable standard for the repair of hernias. Recurrence rate has been greatly reduced since Lichtensen in 1986 first described mesh repair of inguinal hernias. The most common complication arising from inguinal hernia repair even with mesh is recurrence. There are isolated reports of migrated mesh in the three decades of mesh use in hernia repair. We present a case report of a migrated mesh plug presenting with features highly suggestive of an intra-abdominal neoplasm in a 63-year-old man who presented with weight loss, anorexia, fatigue, and a palpable right lower quadrant mass. Work up had revealed a large inflammatory mass involving the cecum and not amenable to percutaneous or colonoscopic biopsy, thus requiring diagnostic laparoscopy. He had a right inguinal hernia repair with mesh 8 years earlier. At diagnostic laparoscopy, an extensive right lower quadrant mass involving the cecum, bladder, and transverse colon and extending to the midline was found, necessitating conversion to open laparotomy and a right hemicolectomy. A mesh plug was found intimately involved with the specimen. Plugs used in inguinal hernia repair rarely migrate. It is rarer still for them to present as a possible colonic mass. This is the first known case report of mesh plug migration presenting as a suspected colonic malignancy.


Asunto(s)
Neoplasias del Colon/diagnóstico , Migración de Cuerpo Extraño/diagnóstico , Mallas Quirúrgicas/efectos adversos , Colectomía , Colitis/diagnóstico , Colon Transverso/patología , Cistitis/diagnóstico , Diagnóstico Diferencial , Reacción a Cuerpo Extraño/diagnóstico , Hernia Inguinal/cirugía , Humanos , Laparoscopía , Masculino , Persona de Mediana Edad , Tomografía Computarizada Espiral , Tiflitis/diagnóstico
14.
R Soc Open Sci ; 3(3): 150628, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27069651

RESUMEN

California sea lions increased from approximately 50 000 to 340 000 animals in the last 40 years, and their pups are starving and stranding on beaches in southern California, raising questions about the adequacy of their food supply. We investigated whether the declining sea lion pup weight at San Miguel rookery was associated with changes in abundance and quality of sardine, anchovy, rockfish and market squid forage. In the last decade off central California, where breeding female sea lions from San Miguel rookery feed, sardine and anchovy greatly decreased in biomass, whereas market squid and rockfish abundance increased. Pup weights fell as forage food quality declined associated with changes in the relative abundances of forage species. A model explained 67% of the variance in pup weights using forage from central and southern California and 81% of the variance in pup weights using forage from the female sea lion foraging range. A shift from high to poor quality forage for breeding females results in food limitation of the pups, ultimately flooding animal rescue centres with starving sea lion pups. Our study is unusual in using a long-term, fishery-independent dataset to directly address an important consequence of forage decline on the productivity of a large marine predator. Whether forage declines are environmentally driven, are due to a combination of environmental drivers and fishing removals, or are due to density-dependent interactions between forage and sea lions is uncertain. However, declining forage abundance and quality was coherent over a large area (32.5-38° N) for a decade, suggesting that trends in forage are environmentally driven.

16.
Gene ; 563(2): 109-14, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25839941

RESUMEN

Microtubules are polymeric structures composed of tubulin subunits. Each subunit consists of a heterodimer of α- and ß-tubulin. At least seven ß-tubulin isotypes, or classes, have been identified in human cells, and constitutive isotype expression appears to be tissue specific. Class III ß-tubulin (ßIII-tubulin) expression is normally confined to testes and tissues derived from neural cristae. However, its expression can be induced in other tissues, both normal and neoplastic, subjected to a toxic microenvironment characterized by hypoxia and poor nutrient supply. In this review, we will summarize the mechanisms underlying ßIII-tubulin constitutive and induced expression. We will also illustrate its capacity to serve as a biomarker of neural commitment in normal tissues and as a pure prognostic biomarker in cancer patients.


Asunto(s)
Neoplasias/metabolismo , Tubulina (Proteína)/metabolismo , Animales , Biomarcadores/metabolismo , Humanos , Microtúbulos/metabolismo , Cresta Neural/metabolismo
17.
PLoS One ; 10(9): e0136058, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26375401

RESUMEN

The Cancer Genome Atlas (TCGA) microRNA (miRNA) initiative has revealed a pivotal role for miRNAs in cancer. Utilizing the TCGA raw data, we performed the first mapping of viral miRNA sequences within cancer and adjacent normal tissues. Results were integrated with TCGA RNA-seq to link the expression of viral miRNAs to the phenotype. Using clinical data and viral miRNA mapping results we also performed outcome analysis. Three lines of evidence lend credence to an active role of viral miRNAs in solid malignancies. First, expression of viral miRNA is consistently higher in cancerous compared to adjacent noncancerous tissues. Second, viral miRNA expression is associated with significantly worse clinical outcome among patients with early stage malignancy. These patients are also featured by increased expression of PD1/PD-L1, a pathway implicated in tumors escaping immune destruction. Finally, a particular cluster of EBV-miRNA (miR-BART2, miR-BART4, miR-BART5, miR-BART18, and miR-BART22) is associated with expression of cytokines known to inhibit host response to cancer. Quantification of specific viral miRNAs may help identify patients who are at risk of poor outcome. These patients may be candidates for novel therapeutic strategies incorporating antiviral agents and/or inhibitors of the PD-1/PD-L1 pathway.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiología , MicroARNs/genética , Neoplasias/patología , Neoplasias/virología , ARN Viral/genética , Progresión de la Enfermedad , Humanos , Estimación de Kaplan-Meier , Neoplasias/genética
18.
Am J Cancer Res ; 5(6): 1862-77, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26269749

RESUMEN

Hypoxia selects the most aggressive and drug-resistant clones in solid malignancies. One of the pivotal transcription factors induced by hypoxia is Hif-1α. However, in serous ovarian cancer (SEOC), Hif-1α expression is not a prognostic biomarker. This study aims to assess the hypothesis that the serine-threonine kinase Nek6 functions as a downstream effector cooperating with Hif-1α in driving ovarian cancer aggressiveness. Nek6 was overexpressed and Hif-1α was silenced in A2780 cells. Nek6 was also stably silenced in Hey cells. The dependence of Nek6 expression on Hif-1α was assayed as a function of hypoxic growth conditions. Nek6 interaction with the cytoskeletal gateway of drug resistance was investigated with far western blot. The co-expression of NEK6, HIF1A, TUBB3 and GBP1 transcripts was quantified with qPCR in two cohorts of SEOC patients (346 locally treated patients and 344 from the TCGA dataset). Nek6 expression is induced by hypoxia in a Hif-1α dependent fashion. Nek6 directly interacts with GBP-1, thus being a component of the cytoskeletal gateway of drug resistance. Nek6 overexpression increases and silencing decreases the anchorage-independent growth of cultured cells. In SEOC patients, NEK6 expression is significantly correlated with HIF1A. Co-expression of NEK6, HIF1A, TUBB3 and GBP1 transcripts identifies a subset of SEOC patients characterized by poor outcome and drug resistance. This study demonstrates the functional relevance of Nek6 in the context of the adaptive response to hypoxia in SEOC. This finding may help identify a sub-population of patients at high risk of relapse to standard first-line chemotherapy.

19.
PLoS One ; 9(10): e110355, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25329915

RESUMEN

Climatic variation alters biochemical and ecological processes, but it is difficult both to quantify the magnitude of such changes, and to differentiate long-term shifts from inter-annual variability. Here, we simultaneously quantify decade-scale isotopic variability at the lowest and highest trophic positions in the offshore California Current System (CCS) by measuring δ15N and δ13C values of amino acids in a top predator, the sperm whale (Physeter macrocephalus). Using a time series of skin tissue samples as a biological archive, isotopic records from individual amino acids (AAs) can reveal the proximate factors driving a temporal decline we observed in bulk isotope values (a decline of ≥1 ‰) by decoupling changes in primary producer isotope values from those linked to the trophic position of this toothed whale. A continuous decline in baseline (i.e., primary producer) δ15N and δ13C values was observed from 1993 to 2005 (a decrease of ∼4‰ for δ15N source-AAs and 3‰ for δ13C essential-AAs), while the trophic position of whales was variable over time and it did not exhibit directional trends. The baseline δ15N and δ13C shifts suggest rapid ongoing changes in the carbon and nitrogen biogeochemical cycling in the offshore CCS, potentially occurring at faster rates than long-term shifts observed elsewhere in the Pacific. While the mechanisms forcing these biogeochemical shifts remain to be determined, our data suggest possible links to natural climate variability, and also corresponding shifts in surface nutrient availability. Our study demonstrates that isotopic analysis of individual amino acids from a top marine mammal predator can be a powerful new approach to reconstructing temporal variation in both biochemical cycling and trophic structure.


Asunto(s)
Aminoácidos/análisis , Isótopos de Carbono/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Isótopos de Nitrógeno/análisis , Agua de Mar/química , Cachalote/metabolismo , Movimientos del Agua , Animales , Monitoreo del Ambiente/métodos , Cadena Alimentaria , Océano Pacífico , Estados del Pacífico , Análisis de Regresión , Piel/química
20.
Oncotarget ; 5(13): 4855-67, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24952592

RESUMEN

Ovarian cancer is the most lethal gynecologic malignancy. Recently, NACT (Neo Adjuvant Chemotherapy) has been tested as alternative approach for the management of ovarian cancer patients. A biological predictor helpful in selecting patients for NACT would be desirable. This study was aimed at identifying actionable mechanisms of resistance to NACT. Expression of a panel of microRNAs was screened in a discovery set of 85 patients. Analysis of the potential targets was conducted in the same RNAs by calculating significant correlations between microRNAs and genes. Quantitative fluorescent immunohistochemistry was employed in a validation set of 109 patients. MiR-193a-5p was significantly overexpressed in the NACT setting. Analysis of its potential targets demonstrated that this microRNA is also significantly correlated with HGF and MET genes. Analysis of protein expression in samples taken before and after NACT demonstrated that both HGF and c-Met are increased after NACT. Patients who relapse shortly after NACT exhibited the highest relative basal expression of both HGF and c-Met, while the opposite phenomenon was observed in the best responders. Mir-193a-5p, HGF and c-Met expression may help select eligible patients for this modality of treatment. Moreover, inhibitors of this pathway may improve the efficacy of NACT.


Asunto(s)
Factor de Crecimiento de Hepatocito/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Proteínas Proto-Oncogénicas c-met/genética , Línea Celular Tumoral , Quimioterapia Adyuvante , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Inmunohistoquímica/métodos , Estimación de Kaplan-Meier , MicroARNs/genética , Persona de Mediana Edad , Terapia Neoadyuvante , Neoplasias Ováricas/patología , Proteínas Proto-Oncogénicas c-met/metabolismo , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Matrices Tisulares , Resultado del Tratamiento
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