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1.
Oncologist ; 29(1): e1-e14, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37358878

RESUMO

BACKGROUND: Previous meta-analyses have indicated that aspirin could affect breast cancer outcomes, particularly when taken post-diagnostically. However, several recent studies appear to show little to no association between aspirin use and breast cancer mortality, all-cause mortality, or recurrence. AIMS: This study aims to conduct an updated systematic review and meta-analysis on the associations of pre-diagnostic and post-diagnostic aspirin use with the aforementioned breast cancer outcomes. It also looks, through subgroup analyses and meta-regressions, at a range of variables that could explain the associations between aspirin use and breast cancer outcomes. RESULTS: In total, 24 papers and 149 860 patients with breast cancer were included. Pre-diagnostic aspirin use was not associated with breast-cancer-specific mortality (HR 0.98, 95% CI, 0.80-1.20, P = .84) or recurrence (HR 0.94, 95% CI, 0.88-1.02, P = .13). Pre-diagnostic aspirin was associated with non-significantly higher all-cause mortality (HR 1.27, 95% CI, 0.95-1.72, P = .11). Post-diagnostic aspirin was not significantly associated with all-cause mortality (HR 0.87, 95% CI, 0.71-1.07, P = .18) or recurrence (HR 0.89, 95% CI, 0.67-1.16, P = .38). Post-diagnostic aspirin use was significantly associated with lower breast-cancer-specific mortality (HR 0.79, 95% CI, 0.64-0.98, P = .032). CONCLUSIONS: The only significant association of aspirin with breast cancer outcomes is lower breast-cancer-specific mortality in patients who used aspirin post-diagnostically. However, factors such as selection bias and high inter-study heterogeneity mean that this result should not be treated as conclusive, and more substantial evidence such as that provided by RCTs is needed before any decisions on new clinical uses for aspirin should be made.


Assuntos
Aspirina , Neoplasias da Mama , Humanos , Feminino , Aspirina/uso terapêutico
2.
Gut Microbes ; 15(2): 2281012, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37992398

RESUMO

The intestinal epithelium is constantly exposed to microbes residing in the lumen. Traditionally, the response to microbial interactions has been studied in cell lines derived from cancerous tissues, e.g. Caco-2. It is, however, unclear how the responses in these cancer cell lines reflect the responses of a normal epithelium and whether there might be microbial strain-specific effects. To address these questions, we derived organoids from the small intestine from a cohort of healthy individuals. Culturing intestinal epithelium on a flat laminin matrix induced their differentiation, facilitating analysis of microbial responses via the apical membrane normally exposed to the luminal content. Here, it was evident that the healthy epithelium across multiple individuals (n = 9) demonstrates robust acute both common and strain-specific responses to a range of probiotic bacterial strains (BB-12Ⓡ, LGGⓇ, DSM33361, and Bif195). Importantly, parallel experiments using the Caco-2 cell line provide no acute response. Collectively, we demonstrate that primary epithelial cells maintained as organoids represent a valuable resource for assessing interactions between the epithelium and luminal microbes across individuals, and that these models are likely to contribute to a better understanding of host microbe interactions.


Assuntos
Microbioma Gastrointestinal , Humanos , Células CACO-2 , Células Epiteliais/metabolismo , Organoides , Epitélio , Mucosa Intestinal/microbiologia
3.
J Clin Invest ; 132(22)2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36136598

RESUMO

Preterm birth is the leading cause of death in children under 5 years of age. Premature infants who receive life-saving oxygen therapy often develop bronchopulmonary dysplasia (BPD), a chronic lung disease. Infants with BPD are at a high risk of abnormal neurodevelopment, including motor and cognitive difficulties. While neural progenitor cells (NPCs) are crucial for proper brain development, it is unclear whether they play a role in BPD-associated neurodevelopmental deficits. Here, we show that hyperoxia-induced experimental BPD in newborn mice led to lifelong impairments in cerebrovascular structure and function as well as impairments in NPC self-renewal and neurogenesis. A neurosphere assay utilizing nonhuman primate preterm baboon NPCs confirmed impairment in NPC function. Moreover, gene expression profiling revealed that genes involved in cell proliferation, angiogenesis, vascular autoregulation, neuronal formation, and neurotransmission were dysregulated following neonatal hyperoxia. These impairments were associated with motor and cognitive decline in aging hyperoxia-exposed mice, reminiscent of deficits observed in patients with BPD. Together, our findings establish a relationship between BPD and abnormal neurodevelopmental outcomes and identify molecular and cellular players of neonatal brain injury that persist throughout adulthood that may be targeted for early intervention to aid this vulnerable patient population.


Assuntos
Displasia Broncopulmonar , Disfunção Cognitiva , Hiperóxia , Nascimento Prematuro , Recém-Nascido , Feminino , Camundongos , Humanos , Animais , Hiperóxia/complicações , Hiperóxia/metabolismo , Animais Recém-Nascidos , Displasia Broncopulmonar/genética , Neurogênese , Disfunção Cognitiva/etiologia , Cognição , Pulmão/metabolismo
4.
Sci Rep ; 8(1): 12139, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30108320

RESUMO

The eastern North American migratory population of monarch butterflies (Danaus plexippus) is in serious decline. Habitat restoration, including adding millions of host plants to compensate for loss of milkweed in US cropland, is a key part of the international conservation strategy to return this iconic butterfly to sustainable status. We report here that Popillia japonica, a polyphagous, invasive beetle, aggregates and feeds on flowers of Asclepias syriaca, the monarch's most important larval food plant, reducing fruiting and seed set by >90% and extensively damaging milkweed umbels in the field. The beetle's ongoing incursion into the monarch's key breeding grounds in the US Midwest is likely to limit pollination and outcrossing of wild and planted milkweeds, reducing their capacity to colonize new areas via seeds. Popillia japonica represents a previously undocumented threat to milkweeds that should be considered in models for monarch habitat restoration.


Assuntos
Asclepias/parasitologia , Borboletas/fisiologia , Besouros/fisiologia , Recuperação e Remediação Ambiental/métodos , Comportamento Alimentar/fisiologia , Migração Animal/fisiologia , Animais , Asclepias/fisiologia , Espécies em Perigo de Extinção , Feminino , Flores , Interações Hospedeiro-Parasita , Espécies Introduzidas , Japão , América do Norte , Polinização , Dinâmica Populacional
5.
JAMA Facial Plast Surg ; 19(4): 303-310, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28278315

RESUMO

IMPORTANCE: An overwhelming amount of data suggest that cardiovascular exercise has a positive effect on the mind and body, although the precise mechanism is not always clear. OBJECTIVE: To assess the clinical and biochemical effects of voluntary cardiovascular exercise on pedicled flaps in a rodent model. DESIGN, SETTING, AND PARTICIPANTS: Eighteen adult Sprague-Dawley male rats were randomized into a resting animal group (RAG) (n=9) and an exercise animal group (EAG) (n=9) for 14 days (July 23, 2013, through July 30, 2013). A pedicled transposition flap was performed on the ventral surface of the rat, and biopsy specimens were taken from the proximal, middle, and distal portions on postoperative days 0, 2, 5, and 9. Flap survival was analyzed planimetrically, and biopsy specimens were analyzed by hematoxylin-eosin-stained microscopy and immunoblotting. The housing, exercise, surgery, and analysis of the rats were conducted at a single basic science research laboratory at the tertiary care center campus of Thomas Jefferson University in Philadelphia, Pennsylvania. EXPOSURES: The rats were caged for 14 days or housed in a cage connected to an exercise wheel and pedometer. MAIN OUTCOMES AND MEASURES: Study measures were gross and micrographic necrosis and expression of proteins within cell survival and apoptosis pathways. RESULTS: A total of 18 rats were studied, 9 in the RAG and 9 in the EAG. the mean (SEM) amount of necrosis in flaps was 41.3% (3%) in the RAG rats and 10.5% (3.5%) in the EAG rats (P < .001). Immunoblotting revealed increased Caspase-9 activity resulting in poly-(adenosine diphosphate-ribose) polymerase 1 cleavage in the RAG vs the EAG, as well as lower phosphorylated protein kinase B (also known as Akt), signal transducer and activator of transcription 3, and total B-cell leukemia/lymphoma 2 protein levels. Throughout the postoperative period, the cumulative vascular endothelial growth factor A levels of the EAG flaps were significantly higher than those of the RAG flaps (2.30 vs 1.25 fold induction [FI], P = .002), with differences of 2.76 vs 1.54 FI in the proximal segment, 2.40 vs 1.20 FI in the middle segment, and 1.90 vs 0.79 FI in the distal segment. A similar response was noted when comparing phosphorylated Akt, with cumulative mean (SEM) p-Akt expression levels of 0.62 (0.04) for RAG and 1.98 (0.09) for EAG (P = .002 between the 2 groups). CONCLUSIONS AND RELEVANCE: Voluntary preoperative exercise improves survival in pedicled fasciocutaneous flaps; the EAG rats had less necrosis, decreased apoptotic markers, and increased amounts of vascular endothelial growth factor A and prosurvival proteins. These results have implications to increase flap survival in other mammal populations, such as humans. LEVEL OF EVIDENCE: 3.


Assuntos
Fenômenos Biomecânicos/fisiologia , Modelos Animais de Doenças , Sobrevivência de Enxerto/fisiologia , Condicionamento Físico Animal , Retalhos Cirúrgicos/patologia , Retalhos Cirúrgicos/fisiologia , Animais , Apoptose/fisiologia , Masculino , Necrose , Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Hum Gene Ther ; 28(6): 482-492, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28335619

RESUMO

Retinal detachment is an acute disorder in humans that is caused by trauma or disease, and it can often lead to permanent visual deficits that result from the death of photoreceptors in the retina. The final pathway for photoreceptor cell death is apoptosis and necroptosis. The X-linked inhibitor of apoptosis (XIAP) has been shown to block both of these cell death pathways. This study tested the effects of XIAP on photoreceptor survival in a feline model of retinal detachment. The study was performed in 12 cats, divided into two experimental groups. Six animals received a subretinal injection of adeno-associated virus (AAV) carrying XIAP, and six animals received AAV carrying green fluorescent protein (GFP) as a control. Three weeks after viral delivery, retinas were detached by injecting C3F8 gas into the subretinal space. Optical coherence tomography revealed that the retinal detachments resolved within 3-6 weeks as the gas was slowly resorbed. Analysis of histological sections through the plane of the detachment showed significant preservation of the photoreceptor layer in AAV-XIAP-treated animals compared to AAV-GFP-treated animals at 9 weeks after the detachment. XIAP-treated detached retinas were similar to intact controls. These studies support the potential for XIAP therapy in the treatment of human retinal detachment.


Assuntos
Terapia Genética/métodos , Vetores Genéticos/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Descolamento Retiniano/terapia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Animais , Apoptose/genética , Gatos , Linhagem Celular , Dependovirus/genética , Dependovirus/metabolismo , Modelos Animais de Doenças , Fluorocarbonos/administração & dosagem , Expressão Gênica , Genes Reporter , Vetores Genéticos/administração & dosagem , Vetores Genéticos/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Injeções Intraoculares , Células Fotorreceptoras Retinianas Cones/patologia , Descolamento Retiniano/genética , Descolamento Retiniano/metabolismo , Descolamento Retiniano/patologia , Transdução de Sinais , Tomografia de Coerência Óptica , Transgenes , Resultado do Tratamento , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
7.
Nanomedicine ; 13(3): 1031-1040, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27888095

RESUMO

This study examines the ability of optically-excited titanium dioxide nanoparticles to influence voltage-gated ion channels in retinal horizontal cells. Voltage clamp recordings were obtained in the presence and absence of TiO2 and ultraviolet laser excitation. Significant current changes were observed in response to UV light, particularly in the -40 mV to +40 mV region where voltage-gated Na+ and K+ channels have the highest conductance. Cells in proximity to UV-excited TiO2 exhibited a left-shift in the current-voltage relation of around 10 mV in the activation of Na+ currents. These trends were not observed in control experiments where cells were excited with UV light without being exposed to TiO2. Electrostatic force microscopy confirmed that electric fields can be induced in TiO2 with UV light. Simulations using the Hodgkin-Huxley model yielded results which agreed with the experimental data and showed the I-V characteristics of individual ion channels in the presence of UV-excited TiO2.


Assuntos
Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Células Horizontais da Retina/efeitos dos fármacos , Células Horizontais da Retina/efeitos da radiação , Titânio/farmacologia , Canais de Sódio Disparados por Voltagem/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/efeitos da radiação , Animais , Peixes-Gato , Células Cultivadas , Potenciais da Membrana , Nanopartículas/química , Técnicas de Patch-Clamp , Células Horizontais da Retina/metabolismo , Titânio/química , Raios Ultravioleta
8.
Head Neck ; 38 Suppl 1: E1152-62, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26332025

RESUMO

BACKGROUND: Poorer surgical outcomes in older patients undergoing locoregional head and neck reconstruction have raised questions about tolerance of aging tissue to iatrogenic ischemic insults. METHODS: We examined the effects of aging on viability of pedicled composite flaps in 2-month and 6-month old Sprague-Dawley male rats and correlated flap survival with vascular endogenous growth factor (VEGF) and VEGF receptor 2-mediated signaling events. Flap segments were assessed for gross/cellular necrosis by optical microscopy and for proangiogenic, apoptotic, and proliferative protein-marker content. RESULTS: Flap necrosis significantly increased with age (4.2% in young vs 49.17% in old), correlating with reduced expression of VEGF, inhibition of signal transducer and activator of transcription 3 (STAT3), and Akt activation, impaired Akt-dependent endothelial nitric oxide synthase (eNOS) phosphorylation, elevated Bax/Bcl-2 ratio, activation of Caspase-3, upregulated nuclear poly (ADP-ribose) polymerase-1 (PARP-1) cleavage and lower proliferating cell nuclear antigen (PCNA) levels. CONCLUSION: Pedicled flap survival is higher in younger rats in part because of unhindered expression of VEGF and enhanced activity of cell survival and promigratory signaling pathways. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1152-E1162, 2016.


Assuntos
Fatores Etários , Rejeição de Enxerto/patologia , Retalhos Cirúrgicos/transplante , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
9.
Adv Exp Med Biol ; 854: 315-21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26427427

RESUMO

We present an optimized surgical technique for feline retinal detachment which allows for natural re-attachment, reduces retinal scarring and vitreal bands, and allows central placement of the detachment in close proximity to the optic nerve. This enables imaging via Optical Coherence Tomography (OCT) and multifocal electroretinography (mfERG) analysis. Ideal detachment conditions involve a lensectomy followed by a three-port pars plana vitrectomy. A 16-20 % retinal detachment is induced by injecting 8 % C3F8 gas into the subretinal space in the central retina with a 42G cannula. The retinal detachment resolves approximately 6 weeks post-surgery. Imaging is enhanced by using a 7.5 and 20 diopter lens for OCT and mfERG fundus imaging, respectively, to compensate for the removed lens.


Assuntos
Doenças do Gato/cirurgia , Retina/cirurgia , Descolamento Retiniano/cirurgia , Vitrectomia/métodos , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/fisiopatologia , Gatos , Eletrorretinografia , Fundo de Olho , Retina/patologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/fisiopatologia , Fatores de Tempo , Tomografia de Coerência Óptica , Resultado do Tratamento
10.
Int J Pediatr Otorhinolaryngol ; 79(12): 2442-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26474834

RESUMO

Parotidectomy is a mainstay of treatment for benign and malignant parotid lesions in children and adults. Depending on surgical methods used and tumor size, parotidectomy may result in significant facial disfigurement as well as functional challenges. We describe a series of four pediatric patients, ages 13-16 who presented to our clinic with a parotid mass. All patients underwent parotidectomy with immediate reconstruction by local tissue rearrangement or free fat graft. Esthetic and functional reconstruction after parotidectomy is not well described in pediatric otolaryngology literature. A review of current literature and description of reconstructive methods is included.


Assuntos
Tecido Adiposo/transplante , Procedimentos Cirúrgicos Dermatológicos , Estética , Face/fisiopatologia , Neoplasias Parotídeas/cirurgia , Adolescente , Face/cirurgia , Feminino , Humanos , Masculino , Glândula Parótida/cirurgia , Neoplasias Parotídeas/patologia , Estudos Retrospectivos
11.
Oncotarget ; 6(19): 17430-44, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26041889

RESUMO

Small nucleolar RNAs (snoRNAs) are dynamically regulated in different tissues and affected in disease. SnoRNAs are processed further to stable smaller RNAs. We sequenced the small RNA transcriptome of prostate cancer (PCa) at different PCa stages and generated a quantified catalogue of 3927 small non-coding RNAs (sncRNAs) detected in normal and malignant prostate tissue. From these, only 1524 are microRNAs. The remaining 2401 sncRNAs represent stable sncRNAs species that originate from snoRNA, tRNA and other sncRNAs. We show that snoRNA-derived RNAs (sdRNAs) display stronger differential expression than microRNAs and are massively upregulated in PCa. SdRNAs account for at least one third of all small RNAs with expression changes in tumor compared to normal adjacent tissue. Multiple sdRNAs can be produced from one snoRNA in a manner related to the conservation of structural snoRNA motifs. Q-PCR analysis in an independent patient cohort (n=106) confirmed the processing patterns of selected snoRNAs (SNORD44, SNORD78, SNORD74 and SNORD81) and the cancer-associated up-regulation of their sdRNAs observed in sequencing data. Importantly, expression of SNORD78 and its sdRNA is significantly higher in a subset of patients that developed metastatic disease demonstrating that snoRNA and sdRNAs may present as novel diagnostic and/or prognostic biomarkers for PCa.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/genética , Invasividade Neoplásica/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Nucleolar Pequeno/genética , Progressão da Doença , Humanos , Masculino , Invasividade Neoplásica/patologia , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
12.
J Robot Surg ; 8(4): 313-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25419245

RESUMO

Transoral robotic surgery (TORS) is being increasingly used in the treatment of head and neck cancer and we wanted to determine the feasibility of predicting TORS access using cephalometric measurements obtained from preoperative imaging. 20 cephalometric measurements were obtained from imaging on 31 TORS base of tongue (BOT) resections and compared to adequacy of exposure. Three measurements were found to be significantly different between the restricted and adequate exposure groups. Distances from posterior pharyngeal wall (PPW) to hyoid, PPW to soft palate and epiglottis to vertical laryngeal angle were all statistically different between the two groups. Receiver operating characteristic (ROC) analysis revealed strong correlation to exposure for all three measurements with cut offs ≤30 mm between the PPW and the hyoid, ≤8.1 mm PPW and soft palate and ≥130° between the epiglottis and vertical plain of the larynx all representing restricted exposure. Duration of surgery for the restricted group, 85 min, was significantly longer than the adequate exposure group, 51 min (p = 0.026). Preoperative measurements of radiographic images of the oropharyngeal working space can predict restricted exposure for TORS resection of the BOT. These measures may be used in conjunction with other subjective assessment parameters to predict which patients could benefit from a staging endoscopy to determine adequate TORS exposure.

13.
Laryngoscope ; 124(11): 2531-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24925374

RESUMO

OBJECTIVES/HYPOTHESIS: Sentinel lymph node biopsy (SLNB) has been utilized for cutaneous melanoma and other malignancies arising from the eye and ocular adnexa. Currently, SLNB requires blue dyes and/or radiopharmaceuticals; both of which have significant shortcomings. This study sought to evaluate the feasibility of SLNB with the use of real-time, contrast-enhanced ultrasound (CEUS) as an alternative technique for tumors arising in the conjunctiva. STUDY DESIGN: Prospective feasibility study in a porcine model. METHODS: Twelve experiments were performed on six non-tumor-bearing Yorkshire swine. An ultrasound contrast agent, Sonazoid (GE Healthcare, Oslo, Norway), (99m) technetium ((99m) Tc), and methylene blue (MB) (Covidien, Mansfield, MA) were injected in the ocular conjunctiva. Sentinel lymph nodes (SLNs) were localized with CEUS and findings were compared to that of MB and (99m) Tc. Fisher exact test was used. RESULTS: Contrast-enhanced SLNs were identified within an average of 6.2 minutes from time of injection of Sonazoid. A total of 17 SLNs were identified by at least one of the three techniques. Correlation between Sonazoid and (99m) Tc was 94.1% (16/17 SLNs). Correlation between (99m) Tc and MB was 88.2% (15/17). One SLN that was positive for (99m) Tc but negative for Sonazoid and was considered to be a false positive (1/17); findings were similar for MB (1/17). Differences between the three techniques were not significant (P = .886). CONCLUSIONS: CEUS-guided injection of conjunctiva for SLNB is technically feasible and correlates well with standard detection techniques. This technique shows promise for rapid, real-time, intraoperative imaging for SLNB, using a widely available imaging modality and avoiding the need for radiopharmaceuticals. LEVEL OF EVIDENCE: NA


Assuntos
Túnica Conjuntiva/cirurgia , Neoplasias da Túnica Conjuntiva/cirurgia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Compostos Férricos , Ferro , Melanoma/cirurgia , Óxidos , Biópsia de Linfonodo Sentinela/métodos , Animais , Neoplasias da Túnica Conjuntiva/patologia , Meios de Contraste , Modelos Animais de Doenças , Estudos de Viabilidade , Injeções Intraoculares , Melanoma/patologia , Distribuição Aleatória , Corantes de Rosanilina , Sensibilidade e Especificidade , Suínos , Coloide de Enxofre Marcado com Tecnécio Tc 99m
14.
Evolution ; 66(9): 2784-97, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22946803

RESUMO

Mating signals may diversify as a byproduct of morphological adaptation to different foraging niches, potentially driving speciation. Although many studies have focused on the direct influence of ecological and sexual selection on signal divergence, the role of indirect mechanisms remains poorly understood. Using phenotypic and molecular datasets, we explored the interplay between morphological and vocal evolution in an avian radiation characterized by dramatic beak variation, the Neotropical woodcreepers (Dendrocolaptinae). We found evidence of a trade-off between the rate of repetition of song syllables and frequency bandwidth: slow paced songs had either narrow or wide frequency bandwidths, and bandwidth decreased as song pace increased. This bounded phenotypic space for song structure supports the hypothesis that passerine birds face a motor constraint during song production. Diversification of acoustic characters within this bounded space was correlated with diversification of beak morphology. In particular, species with larger beaks produced slower songs with narrower frequency bandwidths, suggesting that ecological selection on beak morphology influences the diversification of woodcreeper songs. Because songs in turn mediate mate choice and species recognition in birds, these results indicate a broader role for ecology in avian diversification.


Assuntos
Bico/anatomia & histologia , Evolução Biológica , Canto , Aves Canoras/genética , Animais , América Central , América do Sul , Clima Tropical
15.
J Transl Med ; 10: 155, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22857597

RESUMO

BACKGROUND: Identification of melanoma patients at high risk for recurrence and monitoring for recurrence are critical for informed management decisions. We hypothesized that serum microRNAs (miRNAs) could provide prognostic information at the time of diagnosis unaccounted for by the current staging system and could be useful in detecting recurrence after resection. METHODS: We screened 355 miRNAs in sera from 80 melanoma patients at primary diagnosis (discovery cohort) using a unique quantitative reverse transcription-PCR (qRT-PCR) panel. Cox proportional hazard models and Kaplan-Meier recurrence-free survival (RFS) curves were used to identify a miRNA signature with prognostic potential adjusting for stage. We then tested the miRNA signature in an independent cohort of 50 primary melanoma patients (validation cohort). Logistic regression analysis was performed to determine if the miRNA signature can determine risk of recurrence in both cohorts. Selected miRNAs were measured longitudinally in subsets of patients pre-/post-operatively and pre-/post-recurrence. RESULTS: A signature of 5 miRNAs successfully classified melanoma patients into high and low recurrence risk groups with significant separation of RFS in both discovery and validation cohorts (p = 0.0036, p = 0.0093, respectively). Significant separation of RFS was maintained when a logistic model containing the same signature set was used to predict recurrence risk in both discovery and validation cohorts (p < 0.0001, p = 0.033, respectively). Longitudinal expression of 4 miRNAs in a subset of patients was dynamic, suggesting miRNAs can be associated with tumor burden. CONCLUSION: Our data demonstrate that serum miRNAs can improve accuracy in identifying primary melanoma patients with high recurrence risk and in monitoring melanoma tumor burden over time.


Assuntos
Biomarcadores Tumorais/sangue , Melanoma/genética , MicroRNAs/sangue , Neoplasias Cutâneas/genética , Feminino , Humanos , Masculino , Melanoma/sangue , Pessoa de Meia-Idade , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/sangue
16.
Clin Exp Metastasis ; 28(1): 27-38, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21069438

RESUMO

Approximately 25% of all patients with stage II colorectal cancer will experience recurrent disease and subsequently die within 5 years. MicroRNA-21 (miR-21) is upregulated in several cancer types and has been associated with survival in colon cancer. In the present study we developed a robust in situ hybridization assay using high-affinity Locked Nucleic Acid (LNA) probes that specifically detect miR-21 in formalin-fixed paraffin embedded (FFPE) tissue samples. The expression of miR-21 was analyzed by in situ hybridization on 130 stage II colon and 67 stage II rectal cancer specimens. The miR-21 signal was revealed as a blue chromogenic reaction, predominantly observed in fibroblast-like cells located in the stromal compartment of the tumors. The expression levels were measured using image analysis. The miR-21 signal was determined as the total blue area (TB), or the area fraction relative to the nuclear density (TBR) obtained using a red nuclear stain. High TBR (and TB) estimates of miR-21 expression correlated significantly with shorter disease-free survival (p = 0.004, HR = 1.28, 95% CI: 1.06-1.55) in the stage II colon cancer patient group, whereas no significant correlation with disease-free survival was observed in the stage II rectal cancer group. In multivariate analysis both TB and TBR estimates were independent of other clinical parameters (age, gender, total leukocyte count, K-RAS mutational status and MSI). We conclude that miR-21 is primarily a stromal microRNA, which when measured by image analysis identifies a subgroup of stage II colon cancer patients with short disease-free survival.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , MicroRNAs/metabolismo , Células Estromais/metabolismo , Idoso , Idoso de 80 Anos ou mais , Sondas de DNA/química , Intervalo Livre de Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , MicroRNAs/genética , Análise Multivariada , Estadiamento de Neoplasias , Oligonucleotídeos/química , Valor Preditivo dos Testes , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fatores de Tempo
17.
Methods ; 52(4): 375-81, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20621190

RESUMO

MicroRNAs (miRNAs) constitute a group of small non-coding RNA molecules generally 18-22 base-pairs in length. miRNAs are considered to be negative regulators of gene expression at the level of post-transcription and are important in normal physiological development, tissue homeostasis and disease. The cellular origin of individual microRNAs is of utmost importance for understanding their roles in molecular and biological processes, in multi-cellular and complex structured tissues. For the localization of miRNAs in clinical and experimental formalin-fixed and paraffin-embedded samples we have developed a simple and robust one-day in situ hybridization protocol based on the use of double digoxigenin (DIG)-labeled LNA-DNA chimeric probes. We show that the protocol enables analyses of specificity, and demonstrate the detection of miR-1, miR-21, miR-124, miR-126, miR-145, and miR-205 in human and murine paraffin material. The well established localization of these microRNAs makes them ideal for use as reference microRNAs when optimizing the microRNA in situ hybridization assay for a particular tissue and miRNA.


Assuntos
Hibridização In Situ/métodos , MicroRNAs/análise , Oligonucleotídeos , Animais , Neoplasias da Mama/química , Endopeptidase K/metabolismo , Humanos , Camundongos , Inclusão em Parafina , RNA Nuclear Pequeno , Sensibilidade e Especificidade
18.
Methods ; 50(4): S6-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20215018

RESUMO

microRNAs are small regulatory RNAs that are currently emerging as new biomarkers for cancer and other diseases. In order for biomarkers to be useful in clinical settings, they should be accurately and reliably detected in clinical samples such as formalin fixed paraffin embedded (FFPE) sections and blood serum or plasma. These types of samples represent a challenge in terms of microRNA quantification. A newly developed method for microRNA qPCR using Locked Nucleic Acid (LNA)-enhanced primers enables accurate and reproducible quantification of microRNAs in scarce clinical samples. Here we show that LNA-based microRNA qPCR enables biomarker screening using very low amounts of total RNA from FFPE samples and the results are compared to microarray analysis data. We also present evidence that the addition of a small carrier RNA prior to total RNA extraction, improves microRNA quantification in blood plasma and laser capture microdissected (LCM) sections of FFPE samples.


Assuntos
MicroRNAs/análise , Reação em Cadeia da Polimerase/métodos , Fixadores , Formaldeído , Humanos , Lasers , MicroRNAs/sangue , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Inclusão em Parafina
19.
Appl Radiat Isot ; 67(7-8 Suppl): S168-70, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19394241

RESUMO

The ion transport Monte Carlo code SRIM has been used to calculate single event lineal energy spectra for the products of the boron-neutron capture reaction in a water-based medium. The event spectra have been benchmarked against spectra measured with a boron-loaded tissue-equivalent proportional counter (TEPC). Agreement is excellent and supports the use of Monte Carlo methods in understanding the influence of boron delivery on the effectiveness of boron-neutron capture therapy (BNCT).


Assuntos
Terapia por Captura de Nêutron de Boro/estatística & dados numéricos , Boro/farmacocinética , Boro/uso terapêutico , Radiossensibilizantes/farmacocinética , Radiossensibilizantes/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Hélio/efeitos da radiação , Humanos , Transferência Linear de Energia , Lítio/efeitos da radiação , Método de Monte Carlo , Neoplasias/metabolismo , Neoplasias/radioterapia , Imagens de Fantasmas
20.
Invest Ophthalmol Vis Sci ; 50(3): 1448-53, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19060276

RESUMO

PURPOSE: To evaluate the ability of X-linked inhibitor of apoptosis (XIAP) gene therapy to provide neuroprotection to cells of the outer nuclear layer (ONL) of the retina after retinal detachment. METHODS: Subretinal injections of a recombinant adenoassociated virus (rAAV) encoding either XIAP or green fluorescent protein (GFP; injection control) were performed in the left eye of Brown Norway rats. Two weeks later, retinal detachments were created at the site of viral injection by delivering sodium hyaluronate into the subretinal space. Retinal tissue was harvested at 24 hours after retinal detachment and was analyzed for caspase 3 and 9 activity. Histologic analysis was conducted on samples taken at 3 days and 2 months after detachment to confirm the presence of XIAP or GFP expression and to assess levels of apoptosis and changes in retinal thickness. RESULTS: Caspase assays performed 24 hours after detachment confirmed an expected increase in caspase 3 and 9 activity in the detached regions of GFP-treated retinas, whereas XIAP-treated detached retinas behaved comparably to attached controls. TUNEL analysis of 3-day tissue samples showed fewer apoptotic cells in XIAP-treated detachments than in GFP-treated detachments. At 2 months after the detachment, histology and immunohistochemistry confirmed the preservation of the ONL at sites of XIAP overexpression, whereas the GFP-treated detached retinas had significantly deteriorated. CONCLUSIONS: The results suggest that XIAP confers structural neuroprotection of photoreceptors for at least 2 months after retinal detachment.


Assuntos
Apoptose/efeitos dos fármacos , Dependovirus/genética , Terapia Genética , Células Fotorreceptoras de Vertebrados/patologia , Descolamento Retiniano/terapia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Modelos Animais de Doenças , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Marcação In Situ das Extremidades Cortadas , Masculino , Fármacos Neuroprotetores , Células Fotorreceptoras de Vertebrados/enzimologia , Ratos , Ratos Endogâmicos BN , Descolamento Retiniano/enzimologia , Transfecção
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