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1.
Future Oncol ; 20(10): 579-591, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38060340

RESUMO

Standard-of-care first-line therapy for patients with newly diagnosed glioblastoma (ndGBM) is maximal safe surgical resection, then concurrent radiotherapy and temozolomide, followed by maintenance temozolomide. IGV-001, the first product of the Goldspire™ platform, is a first-in-class autologous immunotherapeutic product that combines personalized whole tumor-derived cells with an antisense oligonucleotide (IMV-001) in implantable biodiffusion chambers, with the intent to induce a tumor-specific immune response in patients with ndGBM. Here, we describe the design and rationale of a randomized, double-blind, phase IIb trial evaluating IGV-001 compared with placebo, both followed by standard-of-care treatment in patients with ndGBM. The primary end point is progression-free survival, and key secondary end points include overall survival and safety.


Glioblastoma (GBM) is a fast-growing brain tumor that happens in about half of all gliomas. Surgery is the first treatment for patients with newly diagnosed GBM, followed by the usual radiation and chemotherapy pills named temozolomide. Temozolomide pills are then given as a long-term treatment. The outcome for the patient with newly diagnosed GBM remains poor. IGV-001 is specially made for each patient. The tumor cells are removed during surgery and mixed in the laboratory with a small DNA, IMV-001. This mix is the IGV-001 therapy that is designed to give antitumor immunity against GBM. IGV-001 is put into small biodiffusion chambers that are irradiated to stop the growth of any tumor cells in the chambers. In the phase IIb study, patients with newly diagnosed GBM are chosen and assigned to either the IGV-001 or the placebo group. A placebo does not contain any active ingredients. The small biodiffusion chambers containing either IGV-001 or placebo are surgically placed into the belly for 48 to 52 h and then removed. Patients then receive the usual radiation and chemotherapy treatment. Patients must be adults aged between 18 and 70 years. Patients also should be able to care for themselves overall, but may be unable to work or have lower ability to function. Patients with tumors on both sides of the brain are not eligible. The main point of this study is to see if IGV-001 helps patients live longer without making the illness worse compared with placebo. Clinical Trial Registration: NCT04485949 (ClinicalTrials.gov).


Assuntos
Neoplasias Encefálicas , Combinação de Medicamentos , Glioblastoma , Humanos , Glioblastoma/terapia , Glioblastoma/tratamento farmacológico , Temozolomida/uso terapêutico , Oligonucleotídeos Antissenso/uso terapêutico , Intervalo Livre de Doença , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamento farmacológico , Imunoterapia , Antineoplásicos Alquilantes/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
J Anim Ecol ; 92(1): 30-43, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36426636

RESUMO

Decades of research have shown that the coevolutionary arms race between avian brood parasites and their hosts can promote phenotypic diversification in hosts and brood parasites. However, relatively little is known about the role of brood parasitism in promoting phenotypic diversification of nestlings. We review field data collected over four decades in Australia, New Caledonia and New Zealand to assess potential for coevolutionary interactions between the shining bronze-cuckoo (Chalcites lucidus) and its hosts, and how diversification at the nestling stage may be generating different subspecies. The shining bronze-cuckoo is a specialist parasite of a few hosts in the family Acanthizidae. It has diversified into subspecies, of which the nestlings closely mimic the respective host nestlings in each region. Additionally, some cuckoo subspecies have polymorphic nestlings. The Acanthizidae hosts have similar breeding and nesting habits and only moderately effective frontline defences against parasitism at cuckoo egg laying or at the egg stages. However, some hosts have developed highly effective defences at the nestling stage by recognising and ejecting cuckoo nestlings from the nest. As with the cuckoo nestlings, some hosts have polymorphic nestlings. The coevolutionary interactions in each region suggest different evolutionary stages of the arms race in which either the parasite or the host is currently in the lead. The presence of moderately effective defences at the egg laying and egg stages might explain why some hosts do not have defences at the nestling stage. The south-Pacific cuckoo - host systems are excellent models to explore the evolutionary mechanisms driving the diversification at the nestling stage in the coevolutionary arms race between avian brood parasites and their hosts.


Assuntos
Parasitos , Passeriformes , Animais , Comportamento de Nidação , Austrália , Evolução Biológica , Interações Hospedeiro-Parasita
3.
Brain ; 145(10): 3666-3680, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-35552612

RESUMO

While several studies have attributed the development of tumour-associated seizures to an excitatory-inhibitory imbalance, we have yet to resolve the spatiotemporal interplay between different types of neuron in glioma-infiltrated cortex. Herein, we combined methods for single unit analysis of microelectrode array recordings with wide-field optical mapping of Thy1-GCaMP pyramidal cells in an ex vivo acute slice model of diffusely infiltrating glioma. This enabled simultaneous tracking of individual neurons from both excitatory and inhibitory populations throughout seizure-like events. Moreover, our approach allowed for observation of how the crosstalk between these neurons varied spatially, as we recorded across an extended region of glioma-infiltrated cortex. In tumour-bearing slices, we observed marked alterations in single units classified as putative fast-spiking interneurons, including reduced firing, activity concentrated within excitatory bursts and deficits in local inhibition. These results were correlated with increases in overall excitability. Mechanistic perturbation of this system with the mTOR inhibitor AZD8055 revealed increased firing of putative fast-spiking interneurons and restoration of local inhibition, with concomitant decreases in overall excitability. Altogether, our findings suggest that diffusely infiltrating glioma affect the interplay between excitatory and inhibitory neuronal populations in a reversible manner, highlighting a prominent role for functional mechanisms linked to mTOR activation.


Assuntos
Glioma , Células Piramidais , Humanos , Potenciais de Ação/fisiologia , Células Piramidais/fisiologia , Neurônios/fisiologia , Convulsões , Serina-Treonina Quinases TOR
4.
Lancet Oncol ; 23(11): 1409-1418, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36243020

RESUMO

BACKGROUND: Topotecan is cytotoxic to glioma cells but is clinically ineffective because of drug delivery limitations. Systemic delivery is limited by toxicity and insufficient brain penetrance, and, to date, convection-enhanced delivery (CED) has been restricted to a single treatment of restricted duration. To address this problem, we engineered a subcutaneously implanted catheter-pump system capable of repeated, chronic (prolonged, pulsatile) CED of topotecan into the brain and tested its safety and biological effects in patients with recurrent glioblastoma. METHODS: We did a single-centre, open-label, single-arm, phase 1b clinical trial at Columbia University Irving Medical Center (New York, NY, USA). Eligible patients were at least 18 years of age with solitary, histologically confirmed recurrent glioblastoma showing radiographic progression after surgery, radiotherapy, and chemotherapy, and a Karnofsky Performance Status of at least 70. Five patients had catheters stereotactically implanted into the glioma-infiltrated peritumoural brain and connected to subcutaneously implanted pumps that infused 146 µM topotecan 200 µL/h for 48 h, followed by a 5-7-day washout period before the next infusion, with four total infusions. After the fourth infusion, the pump was removed and the tumour was resected. The primary endpoint of the study was safety of the treatment regimen as defined by presence of serious adverse events. Analyses were done in all treated patients. The trial is closed, and is registered with ClinicalTrials.gov, NCT03154996. FINDINGS: Between Jan 22, 2018, and July 8, 2019, chronic CED of topotecan was successfully completed safely in all five patients, and was well tolerated without substantial complications. The only grade 3 adverse event related to treatment was intraoperative supplemental motor area syndrome (one [20%] of five patients in the treatment group), and there were no grade 4 adverse events. Other serious adverse events were related to surgical resection and not the study treatment. Median follow-up was 12 months (IQR 10-17) from pump explant. Post-treatment tissue analysis showed that topotecan significantly reduced proliferating tumour cells in all five patients. INTERPRETATION: In this small patient cohort, we showed that chronic CED of topotecan is a potentially safe and active therapy for recurrent glioblastoma. Our analysis provided a unique tissue-based assessment of treatment response without the need for large patient numbers. This novel delivery of topotecan overcomes limitations in delivery and treatment response assessment for patients with glioblastoma and could be applicable for other anti-glioma drugs or other CNS diseases. Further studies are warranted to determine the effect of this drug delivery approach on clinical outcomes. FUNDING: US National Institutes of Health, The William Rhodes and Louise Tilzer Rhodes Center for Glioblastoma, the Michael Weiner Glioblastoma Research Into Treatment Fund, the Gary and Yael Fegel Foundation, and The Khatib Foundation.


Assuntos
Glioblastoma , Glioma , Humanos , Topotecan/efeitos adversos , Glioblastoma/tratamento farmacológico , Convecção , Recidiva Local de Neoplasia/tratamento farmacológico , Glioma/patologia
5.
Proc Natl Acad Sci U S A ; 115(49): 12471-12476, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30397141

RESUMO

Species richness is greatest in the tropics, and much of this diversity is concentrated in mountains. Janzen proposed that reduced seasonal temperature variation selects for narrower thermal tolerances and limited dispersal along tropical elevation gradients [Janzen DH (1967) Am Nat 101:233-249]. These locally adapted traits should, in turn, promote reproductive isolation and higher speciation rates in tropical mountains compared with temperate ones. Here, we show that tropical and temperate montane stream insects have diverged in thermal tolerance and dispersal capacity, two key traits that are drivers of isolation in montane populations. Tropical species in each of three insect clades have markedly narrower thermal tolerances and lower dispersal than temperate species, resulting in significantly greater population divergence, higher cryptic diversity, higher tropical speciation rates, and greater accumulation of species over time. Our study also indicates that tropical montane species, with narrower thermal tolerance and reduced dispersal ability, will be especially vulnerable to rapid climate change.


Assuntos
Distribuição Animal , Biodiversidade , Especiação Genética , Insetos/genética , Insetos/fisiologia , Altitude , Animais , Temperatura , Clima Tropical
6.
Neurobiol Dis ; 134: 104676, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31731042

RESUMO

The purpose of this study is to develop a platform in which the cellular and molecular underpinnings of chronic focal neocortical lesional epilepsy can be explored and use it to characterize seizure-like events (SLEs) in an ex vivo model of infiltrating high-grade glioma. Microelectrode arrays were used to study electrophysiologic changes in ex vivo acute brain slices from a PTEN/p53 deleted, PDGF-B driven mouse model of high-grade glioma. Electrode locations were co-registered to the underlying histology to ascertain the influence of the varying histologic landscape on the observed electrophysiologic changes. Peritumoral, infiltrated, and tumor sites were sampled in tumor-bearing slices. Following the addition of zero Mg2+ solution, all three histologic regions in tumor-bearing slices showed significantly greater increases in firing rates when compared to the control sites. Tumor-bearing slices demonstrated increased proclivity for SLEs, with 40 events in tumor-bearing slices and 5 events in control slices (p-value = .0105). Observed SLEs were characterized by either low voltage fast (LVF) onset patterns or short bursts of repetitive widespread, high amplitude low frequency discharges. Seizure foci comprised areas from all three histologic regions. The onset electrode was found to be at the infiltrated margin in 50% of cases and in the peritumoral region in 36.9% of cases. These findings reveal a landscape of histopathologic and electrophysiologic alterations associated with ictogenesis and spread of tumor-associated seizures.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Glioma/fisiopatologia , Neurônios/fisiologia , Convulsões/fisiopatologia , Potenciais de Ação , Animais , Neoplasias Encefálicas/complicações , Modelos Animais de Doenças , Glioma/complicações , Camundongos Transgênicos , Microeletrodos , Convulsões/complicações
7.
BMC Evol Biol ; 19(1): 52, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744573

RESUMO

BACKGROUND: DNA barcoding utilises a standardised region of the cytochrome c oxidase I (COI) gene to identify specimens to the species level. It has proven to be an effective tool for identification of avian samples. The unique island avifauna of New Zealand is taxonomically and evolutionarily distinct. We analysed COI sequence data in order to determine if DNA barcoding could accurately identify New Zealand birds. RESULTS: We sequenced 928 specimens from 180 species. Additional Genbank sequences expanded the dataset to 1416 sequences from 211 of the estimated 236 New Zealand species. Furthermore, to improve the assessment of genetic variation in non-endemic species, and to assess the overall accuracy of our approach, sequences from 404 specimens collected outside of New Zealand were also included in our analyses. Of the 191 species represented by multiple sequences, 88.5% could be successfully identified by their DNA barcodes. This is likely a conservative estimate of the power of DNA barcoding in New Zealand, given our extensive geographic sampling. The majority of the 13 groups that could not be distinguished contain recently diverged taxa, indicating incomplete lineage sorting and in some cases hybridisation. In contrast, 16 species showed evidence of distinct intra-species lineages, some of these corresponding to recognised subspecies. For species identification purposes a character-based method was more successful than distance and phylogenetic tree-based methods. CONCLUSIONS: DNA barcodes accurately identify most New Zealand bird species. However, low levels of COI sequence divergence in some recently diverged taxa limit the identification power of DNA barcoding. A small number of currently recognised species would benefit from further systematic investigations. The reference database and analysis presented will provide valuable insights into the evolution, systematics and conservation of New Zealand birds.


Assuntos
Evolução Biológica , Aves/classificação , Conservação dos Recursos Naturais , Código de Barras de DNA Taxonômico/métodos , Animais , Aves/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Geografia , Ilhas , Nova Zelândia , Filogenia , Especificidade da Espécie
8.
Neurobiol Dis ; 127: 303-311, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30898669

RESUMO

The cellular activity underlying human focal seizures, and its relationship to key signatures in the EEG recordings used for therapeutic purposes, has not been well characterized despite many years of investigation both in laboratory and clinical settings. The increasing use of microelectrodes in epilepsy surgery patients has made it possible to apply principles derived from laboratory research to the problem of mapping the spatiotemporal structure of human focal seizures, and characterizing the corresponding EEG signatures. In this review, we describe results from human microelectrode studies, discuss some data interpretation pitfalls, and explain the current understanding of the key mechanisms of ictogenesis and seizure spread.


Assuntos
Encéfalo/fisiopatologia , Epilepsia/fisiopatologia , Neurônios/fisiologia , Convulsões/fisiopatologia , Eletrodos Implantados , Eletroencefalografia , Humanos , Microeletrodos
10.
New Phytol ; 223(4): 2054-2062, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31087648

RESUMO

Explaining variation in life history strategies is an enduring goal of evolutionary biology and ecology. Early theory predicted that for plants, annual and perennial life histories reflect adaptations to environments that experience alternative drought regimens. Nevertheless, empirical support for this hypothesis from comparative analyses remains lacking. Here, we test classic life history theory in Heliophila L. (Brassicaceae), a diverse genus of flowering plants native to Africa, controlling for phylogeny and integrating 34 yr of satellite-based drought detection with 2192 herbaria occurrence records. We find that the common ancestor of these species was likely to be an annual, and that perenniality and annuality have repeatedly evolved, an estimated seven and five times, respectively. By comparing historical drought regimens, we show that annuals rather than perennial species occur in environments where droughts are significantly more frequent. We also find evidence that annual plants adapt to predictable drought regimens by escaping drought-prone seasons as seeds. These results yield compelling support for longstanding theoretical predictions by revealing the importance of drought frequency and predictability to explain plant life history. More broadly, this work highlights scalable approaches, integrating herbaria records and remote sensing to address outstanding questions in evolutionary ecology.


Assuntos
Brassicaceae/crescimento & desenvolvimento , Secas , Modelos Logísticos , Filogenia , Especificidade da Espécie
11.
Proc Natl Acad Sci U S A ; 111(34): 12550-5, 2014 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-25114226

RESUMO

Glioblastomas (GBMs) diffusely infiltrate the brain, making complete removal by surgical resection impossible. The mixture of neoplastic and nonneoplastic cells that remain after surgery form the biological context for adjuvant therapeutic intervention and recurrence. We performed RNA-sequencing (RNA-seq) and histological analysis on radiographically guided biopsies taken from different regions of GBM and showed that the tissue contained within the contrast-enhancing (CE) core of tumors have different cellular and molecular compositions compared with tissue from the nonenhancing (NE) margins of tumors. Comparisons with the The Cancer Genome Atlas dataset showed that the samples from CE regions resembled the proneural, classical, or mesenchymal subtypes of GBM, whereas the samples from the NE regions predominantly resembled the neural subtype. Computational deconvolution of the RNA-seq data revealed that contributions from nonneoplastic brain cells significantly influence the expression pattern in the NE samples. Gene ontology analysis showed that the cell type-specific expression patterns were functionally distinct and highly enriched in genes associated with the corresponding cell phenotypes. Comparing the RNA-seq data from the GBM samples to that of nonneoplastic brain revealed that the differentially expressed genes are distributed across multiple cell types. Notably, the patterns of cell type-specific alterations varied between the different GBM subtypes: the NE regions of proneural tumors were enriched in oligodendrocyte progenitor genes, whereas the NE regions of mesenchymal GBM were enriched in astrocytic and microglial genes. These subtype-specific patterns provide new insights into molecular and cellular composition of the infiltrative margins of GBM.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/classificação , Meios de Contraste , Feminino , Glioblastoma/classificação , Humanos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , RNA Neoplásico/genética , Análise de Sequência de RNA , Transcriptoma , Microambiente Tumoral
12.
Surg Endosc ; 28(10): 2949-58, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24879134

RESUMO

BACKGROUND: Preoperative factors predicting symptomatic improvement after transoral fundoplication (TF) in chronic gastroesophageal reflux disease (GERD) patients with persistent symptoms on proton-pump inhibitors (PPIs) therapy have not been elucidated fully. METHODS: Univariate and multivariate logistic regression analyses were performed on data from 158 consecutive patients who underwent TF with the EsophyX device between January 2010 and June 2012 in 14 community centers. Variables included age, gender, body mass index, GERD duration, PPIs therapy duration, presence of hiatal hernia, esophagitis, Hill grade, quality of life scores (QOL) on PPIs, % total time pH < 4, and DeMeester score on reflux testing off PPIs. RESULTS: All patients suffered from typical GERD symptoms. Additionally, 78% (124/158) of patients suffered from atypical symptoms. Six percent (10/158) with recurrent GERD symptoms refractory to PPI therapy underwent revisional procedure (9 laparoscopic Nissen, 1 TF). Median follow-up was 22 (range 10-43) months. For patients with typical symptoms, univariate analyses revealed 4 preoperative factors predictive of successful outcomes: age ≥ 50 [odds ratio (OR) = 2.4, 95% confidence interval (CI) = 1.2-4.8, p = 0.014], GERD Health-related Quality of Life score (GERD-HRQL) ≥ 15 on PPIs (OR = 6.0, CI = 1.2-29.4, p = 0.026, Reflux Symptom Index score > 13 on PPIs (OR = 2.4, CI = 1.1-5.2, p = 0.027), and Gastroesophageal Reflux Symptom Score ≥ 18 on PPIs (OR = 2.6, CI = 1.2-5.8, p = 0.018). Age and GERD-HRQL score remained significant predictors by multivariate analysis. For patients with atypical symptoms, only GERD-HRQL score ≥ 15 on PPIs (OR = 9.9, CI = 0.9-4.6, p = 0.036) was associated with successful outcomes. CONCLUSIONS: Elevated preoperative QOL scores on PPIs and age ≥ 50 were most closely associated with successful outcome of TF in patients with persistent symptoms despite medical therapy.


Assuntos
Fundoplicatura/métodos , Refluxo Gastroesofágico/cirurgia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Esofagite/complicações , Esôfago/lesões , Feminino , Fundoplicatura/efeitos adversos , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , Hérnia Hiatal/complicações , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Qualidade de Vida , Recidiva , Reoperação , Resultado do Tratamento , Adulto Jovem
13.
bioRxiv ; 2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38293120

RESUMO

Gliomas are highly aggressive brain tumors characterized by poor prognosis and composed of diffusely infiltrating tumor cells that intermingle with non-neoplastic cells in the tumor microenvironment, including neurons. Neurons are increasingly appreciated as important reactive components of the glioma microenvironment, due to their role in causing hallmark glioma symptoms, such as cognitive deficits and seizures, as well as their potential ability to drive glioma progression. Separately, mTOR signaling has been shown to have pleiotropic effects in the brain tumor microenvironment, including regulation of neuronal hyperexcitability. However, the local cellular-level effects of mTOR inhibition on glioma-induced neuronal alterations are not well understood. Here we employed neuron-specific profiling of ribosome-bound mRNA via 'RiboTag,' morphometric analysis of dendritic spines, and in vivo calcium imaging, along with pharmacological mTOR inhibition to investigate the impact of glioma burden and mTOR inhibition on these neuronal alterations. The RiboTag analysis of tumor-associated excitatory neurons showed a downregulation of transcripts encoding excitatory and inhibitory postsynaptic proteins and dendritic spine development, and an upregulation of transcripts encoding cytoskeletal proteins involved in dendritic spine turnover. Light and electron microscopy of tumor-associated excitatory neurons demonstrated marked decreases in dendritic spine density. In vivo two-photon calcium imaging in tumor-associated excitatory neurons revealed progressive alterations in neuronal activity, both at the population and single-neuron level, throughout tumor growth. This in vivo calcium imaging also revealed altered stimulus-evoked somatic calcium events, with changes in event rate, size, and temporal alignment to stimulus, which was most pronounced in neurons with high-tumor burden. A single acute dose of AZD8055, a combined mTORC1/2 inhibitor, reversed the glioma-induced alterations on the excitatory neurons, including the alterations in ribosome-bound transcripts, dendritic spine density, and stimulus evoked responses seen by calcium imaging. These results point to mTOR-driven pathological plasticity in neurons at the infiltrative margin of glioma - manifested by alterations in ribosome-bound mRNA, dendritic spine density, and stimulus-evoked neuronal activity. Collectively, our work identifies the pathological changes that tumor-associated excitatory neurons experience as both hyperlocal and reversible under the influence of mTOR inhibition, providing a foundation for developing therapies targeting neuronal signaling in glioma.

14.
J Neurooncol ; 112(3): 375-82, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23504257

RESUMO

Molecular subtypes of glioblastoma (GBM) with distinct alterations have been identified. There is need for reproducible, versatile preclinical models that resemble specific GBM phenotypes to facilitate preclinical testing of novel therapies. We present a cell line-based murine proneural GBM model and characterize its response to radiation therapy. Proneural gliomas were generated by injecting PDGF-IRES-Cre retrovirus into the subcortical white matter of adult mice that harbor floxed tumor suppressors (Pten and p53) and stop-floxed reporters. Primary cell cultures were generated from the retrovirus induced tumors and maintained in vitro for multiple passages. RNA sequencing-based expression profiling of the resulting cell lines was performed. The tumorigenic potential of the cells was assessed by intracranial injection into adult naïve mice from different strains. Tumor growth was assessed by bioluminescence imaging (BLI). BLI for tumor cells and brain slices were obtained and compared to in vivo BLI. Response to whole-brain radiation was assessed in glioma-bearing animals. Intracranial injection of Pdgf(+)Pten(-/-)p53(-/-)luciferase(+) glioma cells led to formation of GBM-like tumors with 100 % efficiency (n = 48) and tumorigenesis was retained for more than 3 generations. The cell lines specifically resembled proneural GBM based on expression profiling by RNA-Seq. Pdgf(+)Pten(-/-)p53(-/-)luciferase(+) cell number correlated with BLI signal. Serial BLI measured tumor growth and correlated with size and location by ex vivo imaging. Moreover, BLI predicted tumor-related mortality with a 93 % risk of death within 5 days following a BLI signal between 1 × 10(8) and 5 × 10(8) photons/s cm(2). BLI signal had transient but significant response following radiotherapy, which corresponded to a modest survival benefit for radiated mice (p < 0.05). Intracranial injection of Pdgf(+)Pten(-/-)p53(-/-)luciferase(+) cells constitutes a novel and highly reproducible model, recapitulating key features of human proneural GBM, and can be used to evaluate tumor-growth and response to therapy.


Assuntos
Neoplasias Encefálicas , Modelos Animais de Doenças , Glioma , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Genes Supressores de Tumor , Glioma/genética , Glioma/patologia , Glioma/radioterapia , Camundongos , Camundongos Knockout , Transplante de Neoplasias , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
15.
Proc Natl Acad Sci U S A ; 107(37): 16201-6, 2010 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-20805485

RESUMO

New Zealand's extinct flightless moa radiated rapidly into a large number of morphologically diverse species, which produced an equally large range of egg morphologies. The exact number of moa species, as well as the characteristics of the eggs they laid, remains contentious. Moreover, like most extinct species, we understand little about their nesting and incubation habits. We used a modified ancient DNA extraction procedure to recover exogenous mitochondrial and nuclear DNA from the inside and outside surfaces of moa eggs. We used sequences from the inside of 69 eggshells to directly assign these remains to seven of the 10 currently recognized moa species. In addition we were able to assign, to the species level, six of the rare reconstructed "whole" eggs. These molecular results enabled us to identify two distinct lineages within the genus Euryapteryx. Members of these lineages differed in eggshell thickness, with one lineage being characterized by a relatively thin eggshell. Unexpectedly, several thin-shelled eggs were also shown to belong to the heaviest moa of the genera Dinornis, Euryapteryx and Emeus, making these, to our knowledge, the most fragile of all avian eggs measured to date. Moreover, sex-specific DNA recovered from the outer surfaces of eggshells belonging to species of Dinornis and Euryapteryx suggest that these very thin eggs were likely to have been incubated by the lighter males. The thin nature of the eggshells of these larger species of moa, even if incubated by the male, suggests that egg breakage in these species would have been common if the typical contact method of avian egg incubation was used.


Assuntos
DNA/genética , Extinção Biológica , Comportamento de Nidação , Paleógnatas/genética , Filogenia , Animais , Sequência de Bases , Casca de Ovo/química , Casca de Ovo/metabolismo , Feminino , Masculino , Nova Zelândia , Paleógnatas/anatomia & histologia , Paleógnatas/classificação , Paleógnatas/fisiologia
16.
R Soc Open Sci ; 10(7): 230337, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37416829

RESUMO

Individual animals should adjust diets according to food availability. We used DNA metabarcoding to construct individual-level dietary timeseries for elephants from two family groups in Kenya varying in habitat use, social position and reproductive status. We detected at least 367 dietary plant taxa, with up to 137 unique plant sequences in one fecal sample. Results matched well-established trends: elephants tended to eat more grass when it rained and other plants when dry. Nested within these switches from 'grazing' to 'browsing' strategies, dietary DNA revealed seasonal shifts in food richness, composition and overlap between individuals. Elephants of both families converged on relatively cohesive diets in dry seasons but varied in their maintenance of cohesion during wet seasons. Dietary cohesion throughout the timeseries of the subdominant 'Artists' family was stronger and more consistently positive compared to the dominant 'Royals' family. The greater degree of individuality within the dominant family's timeseries could reflect more divergent nutritional requirements associated with calf dependency and/or priority access to preferred habitats. Whereas theory predicts that individuals should specialize on different foods under resource scarcity, our data suggest family bonds may promote cohesion and foster the emergence of diverse feeding cultures reflecting links between social behaviour and nutrition.

17.
Clin Cancer Res ; 29(21): 4399-4407, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611077

RESUMO

PURPOSE: While MGMT promoter methylation (mMGMT) is predictive of response to alkylating chemotherapy and guides treatment decisions in glioblastoma, its role in grade 2 and 3 glioma remains unclear. Recent data suggest that mMGMT is prognostic of progression-free survival in 1p/19q-codeleted oligodendrogliomas, but an effect on overall survival (OS) has not been demonstrated. EXPERIMENTAL DESIGN: We identified patients with newly diagnosed 1p/19q-codeleted gliomas and known MGMT promoter status in the National Cancer Database from 2010 to 2019. Multivariable Cox proportional hazards regression modeling was used to assess the effect of mMGMT on OS after adjusting for age, sex, race, comorbidity, grade, extent of resection, chemotherapy, and radiotherapy. RESULTS: We identified 1,297 eligible patients, 938 (72.3%) of whom received chemotherapy in their initial course of treatment. The MGMT promoter was methylated in 1,009 (77.8%) patients. Unmethylated MGMT (uMGMT) was associated with worse survival compared with mMGMT [70% {95% confidence interval (CI), 64%-77%} vs. 81% (95% CI, 78%-85%); P < 0.001; adjusted HR (aHR), 2.35 (95% CI, 1.77-3.14)]. uMGMT was associated with worse survival in patients who received chemotherapy [63% (95% CI, 55-73%) vs. 80% (95% CI, 76%-84%); P < 0.001; aHR, 2.61 (95% CI, 1.89-3.60)] but not in patients who did not receive chemotherapy [P = 0.38; HR, 1.31 (95% CI, 0.71-2.42)]. Similar results were observed regardless of World Health Organization grade and after single- or multiagent chemotherapy. CONCLUSIONS: Our study demonstrates an association between mMGMT and OS in 1p/19q-codeleted gliomas. MGMT promoter status should be considered as a stratification factor in future clinical trials of 1p/19q-codeleted gliomas that use OS as an endpoint.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/diagnóstico , Metilação , Glioma/tratamento farmacológico , Glioma/genética , Glioma/diagnóstico , Prognóstico , Metilação de DNA , Isocitrato Desidrogenase/genética , Enzimas Reparadoras do DNA/genética , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética
18.
Nat Commun ; 14(1): 2586, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142563

RESUMO

Glioblastoma (GBM) diffusely infiltrates the brain and intermingles with non-neoplastic brain cells, including astrocytes, neurons and microglia/myeloid cells. This complex mixture of cell types forms the biological context for therapeutic response and tumor recurrence. We used single-nucleus RNA sequencing and spatial transcriptomics to determine the cellular composition and transcriptional states in primary and recurrent glioma and identified three compositional 'tissue-states' defined by cohabitation patterns between specific subpopulations of neoplastic and non-neoplastic brain cells. These tissue-states correlated with radiographic, histopathologic, and prognostic features and were enriched in distinct metabolic pathways. Fatty acid biosynthesis was enriched in the tissue-state defined by the cohabitation of astrocyte-like/mesenchymal glioma cells, reactive astrocytes, and macrophages, and was associated with recurrent GBM and shorter survival. Treating acute slices of GBM with a fatty acid synthesis inhibitor depleted the transcriptional signature of this pernicious tissue-state. These findings point to therapies that target interdependencies in the GBM microenvironment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/patologia , Prognóstico , Neoplasias Encefálicas/patologia , Glioma/genética , Astrócitos/metabolismo , Microambiente Tumoral/genética
19.
Sci Data ; 10(1): 87, 2023 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-36774440

RESUMO

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data.


Assuntos
COVID-19 , Humanos , Adaptação Psicológica , Comportamentos Relacionados com a Saúde , Pandemias , Inquéritos e Questionários
20.
J Voice ; 36(1): 140.e1-140.e21, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32868146

RESUMO

OBJECTIVE: To examine flow phonation characteristics with regard to vocal fold vibration and voice source properties in vocally healthy adults using multimodality voice measurements across various phonation types (breathy, neutral, flow, and pressed) and loudness conditions (typical, loud, and soft). PARTICIPANTS AND METHODS: Vocal fold vibration, airflow, acoustic, and subglottal pressure was analyzed in 13 untrained voices (six female and seven male). Participants repeated the syllable / pæ:/ using breathy, neutral, flow, and pressed phonation during typical, loud, and soft loudness conditions. Glottal area (GA) waveforms were extracted from high-speed videoendoscopy; glottal flow was derived from inverse filtering the airflow or the audio signal; and subglottal pressure was measured as the intraoral pressure during /p/ occlusion. RESULTS: Changes in phonation type and loudness conditions resulted in systematic variations across the relative peak closing velocity derived from the GA waveform for both males and females. Amplitude quotient derived from the flow glottogram varied across phonation types for males. CONCLUSION: Multimodality evaluation using the GA waveform and the inverse filtered waveforms revealed a complex pattern that varied as a function of phonation types and loudness conditions across males and females. Emerging findings from this study suggests that future large-scale studies should focus on spatial and temporal features of closing speed and closing duration for differentiating flow phonation from other phonation types in untrained adults with and without voice disorders.


Assuntos
Fonação , Voz , Adulto , Feminino , Glote/diagnóstico por imagem , Humanos , Masculino , Vibração , Prega Vocal
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