Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
1.
Nature ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009005

RESUMO

Transmission spectroscopy has been a workhorse technique over the past two decades to constrain the physical and chemical properties of exoplanet atmospheres 1-5. One of its classical key assumptions is that the portion of the atmosphere it probes - the terminator region - is homogeneous. Several works in the past decade, however, have put this into question for highly irradiated, hot (Teq ≳ 1000 K) gas giant exoplanets both empirically 6-10 and via 3-dimensional modelling 11-17. While models predict clear differences between the evening (day-to-night) and morning (night-to-day) terminators, direct morning/evening transmission spectra in a wide wavelength range has not been reported for an exoplanet to date. Under the assumption of precise and accurate orbital parameters on WASP-39 b, here we report the detection of inhomogeneous terminators on the exoplanet WASP-39 b, which allows us to retrieve its morning and evening transmission spectra in the near-infrared (2 - 5 µm) using JWST. We observe larger transit depths in the evening which are, on average, 405±88 ppm larger than the morning ones, also having qualitatively larger features than the morning spectrum. The spectra are best explained by models in which the evening terminator is hotter than the morning terminator by 177 - 57 + 65 K with both terminators having C/O ratios consistent with solar. General circulation models (GCMs) predict temperature differences broadly consistent with the above value and point towards a cloudy morning terminator and a clearer evening terminator.

2.
Nature ; 614(7949): 670-675, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623550

RESUMO

The Saturn-mass exoplanet WASP-39b has been the subject of extensive efforts to determine its atmospheric properties using transmission spectroscopy1-4. However, these efforts have been hampered by modelling degeneracies between composition and cloud properties that are caused by limited data quality5-9. Here we present the transmission spectrum of WASP-39b obtained using the Single-Object Slitless Spectroscopy (SOSS) mode of the Near Infrared Imager and Slitless Spectrograph (NIRISS) instrument on the JWST. This spectrum spans 0.6-2.8 µm in wavelength and shows several water-absorption bands, the potassium resonance doublet and signatures of clouds. The precision and broad wavelength coverage of NIRISS/SOSS allows us to break model degeneracies between cloud properties and the atmospheric composition of WASP-39b, favouring a heavy-element enhancement ('metallicity') of about 10-30 times the solar value, a sub-solar carbon-to-oxygen (C/O) ratio and a solar-to-super-solar potassium-to-oxygen (K/O) ratio. The observations are also best explained by wavelength-dependent, non-grey clouds with inhomogeneous coverageof the planet's terminator.

3.
Nature ; 620(7973): 292-298, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37257843

RESUMO

Close-in giant exoplanets with temperatures greater than 2,000 K ('ultra-hot Jupiters') have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble Space Telescope (HST) and Spitzer Space Telescope1-3. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis3-12. Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS13 instrument on the JWST. The data span 0.85 to 2.85 µm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6σ confidence) and evidence for optical opacity, possibly attributable to H-, TiO and VO (combined significance of 3.8σ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy-element abundance ('metallicity', [Formula: see text] times solar) and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the substellar point that decreases steeply and symmetrically with longitude towards the terminators.

4.
Development ; 150(3)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36625162

RESUMO

Cell morphology is crucial for all cell functions. This is particularly true for glial cells as they rely on complex shape to contact and support neurons. However, methods to quantify complex glial cell shape accurately and reproducibly are lacking. To address this, we developed the image analysis pipeline 'GliaMorph'. GliaMorph is a modular analysis toolkit developed to perform (1) image pre-processing, (2) semi-automatic region-of-interest selection, (3) apicobasal texture analysis, (4) glia segmentation, and (5) cell feature quantification. Müller glia (MG) have a stereotypic shape linked to their maturation and physiological status. Here, we characterized MG on three levels: (1) global image-level, (2) apicobasal texture, and (3) regional apicobasal vertical-to-horizontal alignment. Using GliaMorph, we quantified MG development on a global and single-cell level, showing increased feature elaboration and subcellular morphological rearrangement in the zebrafish retina. As proof of principle, we analysed expression changes in a mouse glaucoma model, identifying subcellular protein localization changes in MG. Together, these data demonstrate that GliaMorph enables an in-depth understanding of MG morphology in the developing and diseased retina.


Assuntos
Células Ependimogliais , Peixe-Zebra , Animais , Camundongos , Retina/metabolismo , Neuroglia/metabolismo , Neurônios
5.
J Neurosci ; 44(25)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38658168

RESUMO

Hexanucleotide repeat expansions within the gene C9ORF72 are the most common cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). This disease-causing expansion leads to a reduction in C9ORF72 expression levels in patients, suggesting loss of C9ORF72 function could contribute to disease. To further understand the consequences of C9ORF72 deficiency in vivo, we generated a c9orf72 mutant zebrafish line. Analysis of the adult female spinal cords revealed no appreciable neurodegenerative pathology such as loss of motor neurons or increased levels of neuroinflammation. However, detailed examination of adult female c9orf72-/- retinas showed prominent neurodegenerative features, including a decrease in retinal thickness, gliosis, and an overall reduction in neurons of all subtypes. Analysis of rod and cone cells within the photoreceptor layer showed a disturbance in their outer segment structure and rhodopsin mislocalization from rod outer segments to their cell bodies and synaptic terminals. Thus, C9ORF72 may play a previously unappreciated role in retinal homeostasis and suggests C9ORF72 deficiency can induce tissue specific neuronal loss.


Assuntos
Proteína C9orf72 , Retina , Peixe-Zebra , Animais , Feminino , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Retina/metabolismo , Retina/patologia , Animais Geneticamente Modificados , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/deficiência , Proteínas/genética , Proteínas/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Medula Espinal/metabolismo , Medula Espinal/patologia
6.
J Neurosci ; 42(4): 702-716, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34876467

RESUMO

The Parkinson's disease (PD) risk gene GTP cyclohydrolase 1 (GCH1) catalyzes the rate-limiting step in tetrahydrobiopterin (BH4) synthesis, an essential cofactor in the synthesis of monoaminergic neurotransmitters. To investigate the mechanisms by which GCH1 deficiency may contribute to PD, we generated a loss of function zebrafish gch1 mutant (gch1-/-), using CRISPR/Cas technology. gch1-/- zebrafish develop marked monoaminergic neurotransmitter deficiencies by 5 d postfertilization (dpf), movement deficits by 8 dpf and lethality by 12 dpf. Tyrosine hydroxylase (Th) protein levels were markedly reduced without loss of ascending dopaminergic (DAergic) neurons. L-DOPA treatment of gch1-/- larvae improved survival without ameliorating the motor phenotype. RNAseq of gch1-/- larval brain tissue identified highly upregulated transcripts involved in innate immune response. Subsequent experiments provided morphologic and functional evidence of microglial activation in gch1-/- The results of our study suggest that GCH1 deficiency may unmask early, subclinical parkinsonism and only indirectly contribute to neuronal cell death via immune-mediated mechanisms. Our work highlights the importance of functional validation for genome-wide association studies (GWAS) risk factors and further emphasizes the important role of inflammation in the pathogenesis of PD.SIGNIFICANCE STATEMENT Genome-wide association studies have now identified at least 90 genetic risk factors for sporadic Parkinson's disease (PD). Zebrafish are an ideal tool to determine the mechanistic role of genome-wide association studies (GWAS) risk genes in a vertebrate animal model. The discovery of GTP cyclohydrolase 1 (GCH1) as a genetic risk factor for PD was counterintuitive, GCH1 is the rate-limiting enzyme in the synthesis of dopamine (DA), mutations had previously been described in the non-neurodegenerative movement disorder dopa-responsive dystonia (DRD). Rather than causing DAergic cell death (as previously hypothesized by others), we now demonstrate that GCH1 impairs tyrosine hydroxylase (Th) homeostasis and activates innate immune mechanisms in the brain and provide evidence of microglial activation and phagocytic activity.


Assuntos
Encéfalo/enzimologia , GTP Cicloidrolase/deficiência , Homeostase/fisiologia , Imunidade Inata/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Animais Geneticamente Modificados , Encéfalo/imunologia , Neurônios Dopaminérgicos/enzimologia , Neurônios Dopaminérgicos/imunologia , GTP Cicloidrolase/genética , Predisposição Genética para Doença/genética , Doença de Parkinson/enzimologia , Doença de Parkinson/genética , Doença de Parkinson/imunologia , Análise de Sequência de RNA/métodos , Tirosina 3-Mono-Oxigenase/antagonistas & inibidores , Tirosina 3-Mono-Oxigenase/genética , Peixe-Zebra
7.
Nature ; 549(7671): 238-241, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28905896

RESUMO

As an exoplanet transits its host star, some of the light from the star is absorbed by the atoms and molecules in the planet's atmosphere, causing the planet to seem bigger; plotting the planet's observed size as a function of the wavelength of the light produces a transmission spectrum. Measuring the tiny variations in the transmission spectrum, together with atmospheric modelling, then gives clues to the properties of the exoplanet's atmosphere. Chemical species composed of light elements-such as hydrogen, oxygen, carbon, sodium and potassium-have in this way been detected in the atmospheres of several hot giant exoplanets, but molecules composed of heavier elements have thus far proved elusive. Nonetheless, it has been predicted that metal oxides such as titanium oxide (TiO) and vanadium oxide occur in the observable regions of the very hottest exoplanetary atmospheres, causing thermal inversions on the dayside. Here we report the detection of TiO in the atmosphere of the hot-Jupiter planet WASP-19b. Our combined spectrum, with its wide spectral coverage, reveals the presence of TiO (to a confidence level of 7.7σ), a strongly scattering haze (7.4σ) and sodium (3.4σ), and confirms the presence of water (7.9σ) in the atmosphere.

8.
J Perianesth Nurs ; 38(5): 693-702, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37269275

RESUMO

PURPOSE: Describe the impact of the implementation of an evidence-based pediatric preoperative risk assessment (PPRA) checklist on the frequency of postanesthesia care unit (PACU) nursing assessments and interventions in children at risk for respiratory complications during emergence from anesthesia. DESIGN: Prospective pre-/postdesign. METHODS: Pediatric perianesthesia nurses assessed 100 children preintervention according to current standard. After nurses received pediatric preoperative risk factor (PPRF) education, another 100 children were assessed postintervention using the PPRA checklist. Pre-/postpatients were unmatched for statistical purposes due to two different groups. Frequency of PACU nursing respiratory assessments/interventions was evaluated. FINDINGS: Demographic variables, risk factors, frequency of nursing assessments/interventions were summarized in pre-/postinterventions. Significant differences (P < .001) were noted between pre-/postintervention groups with increased frequency of postnursing assessments/interventions that correlated with increased risk factors and weighted risk factors. CONCLUSIONS: By identifying total PPRFs, PACU nurses used their plan of care to frequently assess and pre-emptively intervene with children who had increased risk factors to prevent or mitigate respiratory complications on emergence from anesthesia.


Assuntos
Lista de Checagem , Melhoria de Qualidade , Humanos , Criança , Estudos Prospectivos , Medição de Risco , Documentação
9.
J Perianesth Nurs ; 38(5): 782-786, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37269281

RESUMO

PURPOSE: To evaluate the effectiveness of the American Society of Perianesthesia Nurses (ASPAN) pediatric competency-based orientation (PCBO) education program on knowledge, confidence, and early recognition of nursing expertise among perianesthesia nurses in an acute care setting. DESIGN: A quasi-experimental pre/post survey-intervention design. METHODS: Sixty perianesthesia nurses with experience ranging from less than 5 years to more than 20 years were included. A chapter review survey was completed to assess knowledge before reviewing the chapters and again after reviewing the ASPAN PCBO materials. A presurvey assessing confidence levels, decision making abilities, and early detection of knowledge regarding pediatric patients' expertise were obtained at the beginning of the study. At the end of the study, a post-study survey was completed to evaluate the effectiveness of the intervention. Random codes were assigned to each participant to ensure that the participants' information was blinded. FINDINGS: Perianesthesia nurses' knowledge increased from pre to post intervention with one of the three sets of chapters (Set 2) statistically significant. Perianesthesia nurses' confidence and recognition of nursing expertise scores increased statistically significant from pre to post intervention. Both confidence (with 33 items [P value ≤ .001]) and recognition of nursing expertise (with 16 items [P value ≤ 0.001]) were statistically significant. CONCLUSIONS: The ASPAN PCBO was shown to be statistically effective at increasing knowledge, building expertise, promoting confidence, and improving decision making skills. The plan is for the ASPAN PCBO to be incorporated into the new-hire perianesthesia orientation didactic and the competency plan.


Assuntos
Competência Clínica , Enfermeiras e Enfermeiros , Humanos , Estados Unidos , Criança , Conhecimento
10.
J Perianesth Nurs ; 37(6): 827-833, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35490143

RESUMO

PURPOSE: The purpose of this study was to describe and validate the association between patient's self-administered correct site checklist and perceptions of importance for safe surgery. DESIGN: A multisite nonexperimental, quantitative, descriptive study. METHODS: A convenience sample of 173 adult patients from four different geographical multisite hospitals was included in the study. Inclusion criteria were age 18 to 75 years old, scheduled for surgery/procedure with laterality and ability to follow instructions. After IRB approval, investigators explained the purpose of the study, process and obtained consent from willing participants. Participants with clinical or behavioral limitations were excluded from the study. Participants completed a 24 item survey before and during surgery using a four-point Likert scale from one (not important) to four (extremely important). Descriptive data was analyzed using means, standard deviations, and percentage. All data was summarized and analyzed with STATA 12. FINDINGS: Most of the participants perceived the importance of the survey checklist items positively implying that the active engagement is an important role for safe surgery. However, a few participants reported some of the items as not important/somewhat important: "It is on my left or right side" (6.9%); "surgery on my: (state your limb) and (right or left site) (1.9-3%); "check electronic access or copy of imaging with correct name and site" (14.9%); "state your name and birthday" (4%), "check correct ID bracelet information" (2.9%) and "believe in having an active role in preventing error" (2.3%). Some participants responded, "My surgeon knows it or surgery has been scheduled".  Findings indicated that even though the importance of correct site surgery is critical for patient's surgery, a few patients reported it as noncritical and relied on healthcare team for their safety. CONCLUSIONS: This study validated the importance of the patients' perceived roles in promoting safe, correct site surgery and by engaging patients in mitigating correct site surgical errors. Therefore, inclusion of patients as an integral part of the healthcare team is necessary through education and encouragement to speak out.


Assuntos
Lista de Checagem , Erros Médicos , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Erros Médicos/prevenção & controle , Equipe de Assistência ao Paciente , Gestão de Riscos , Inquéritos e Questionários
11.
J Neurosci Res ; 99(11): 2774-2792, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34520578

RESUMO

Myelination is crucial for the development and maintenance of axonal integrity, especially fast axonal action potential conduction. There is increasing evidence that glutamate signaling and release through neuronal activity modulates the myelination process. In this study, we examine the effect of manipulating glutamate signaling on myelination of oligodendrocyte (OL) lineage cells and their development in zebrafish (zf). We use the "intensity-based glutamate-sensing fluorescent reporter" (iGluSnFR) in the zf model (both sexes) to address the hypothesis that glutamate is implicated in regulation of myelinating OLs. Our results show that glial iGluSnFR expression significantly reduces OL lineage cell number and the expression of myelin markers in larvae (zfl) and adult brains. The specific glutamate receptor agonist, L-AP4, rescues this iGluSnFR effect by significantly increasing the expression of the myelin-related genes, plp1b and mbpa, and enhances myelination in L-AP4-injected zfl compared to controls. Furthermore, we demonstrate that degrading glutamate using Glutamat-Pyruvate Transaminase (GPT) or the blockade of glutamate reuptake by L-trans-pyrrolidine-2,4-dicarboxylate (PDC) significantly decreases myelin-related genes and drastically declines myelination in brain ventricle-injected zfl. Moreover, we found that myelin-specific ClaudinK (CldnK) and 36K protein expression is significantly decreased in iGluSnFR-expressing zfl and adult brains compared to controls. Taken together, this study confirms that glutamate signaling is directly required for the preservation of myelinating OLs and for the myelination process itself. These findings further suggest that glutamate signaling may provide novel targets to therapeutically boost remyelination in several demyelinating diseases of the CNS.


Assuntos
Oligodendroglia , Peixe-Zebra , Animais , Axônios/metabolismo , Feminino , Glutamatos/metabolismo , Masculino , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo
12.
EMBO Rep ; 20(8): e47047, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31379129

RESUMO

We identify a novel endothelial membrane behaviour in transgenic zebrafish. Cerebral blood vessels extrude large transient spherical structures that persist for an average of 23 min before regressing into the parent vessel. We term these structures "kugeln", after the German for sphere. Kugeln are only observed arising from the cerebral vessels and are present as late as 28 days post fertilization. Kugeln do not communicate with the vessel lumen and can form in the absence of blood flow. They contain little or no cytoplasm, but the majority are highly positive for nitric oxide reactivity. Kugeln do not interact with brain lymphatic endothelial cells (BLECs) and can form in their absence, nor do they perform a scavenging role or interact with macrophages. Inhibition of actin polymerization, Myosin II, or Notch signalling reduces kugel formation, while inhibition of VEGF or Wnt dysregulation (either inhibition or activation) increases kugel formation. Kugeln represent a novel Notch-dependent NO-containing endothelial organelle restricted to the cerebral vessels, of currently unknown function.


Assuntos
Vasos Sanguíneos/citologia , Encéfalo/citologia , Células Endoteliais/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Neovascularização Fisiológica/genética , Peixe-Zebra/embriologia , Actinas/antagonistas & inibidores , Actinas/genética , Actinas/metabolismo , Animais , Animais Geneticamente Modificados , Vasos Sanguíneos/embriologia , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/ultraestrutura , Encéfalo/irrigação sanguínea , Encéfalo/embriologia , Encéfalo/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Circulação Cerebrovascular/genética , Embrião não Mamífero , Células Endoteliais/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Miosina Tipo II/antagonistas & inibidores , Miosina Tipo II/genética , Miosina Tipo II/metabolismo , Óxido Nítrico/metabolismo , Organelas/metabolismo , Organelas/ultraestrutura , Polimerização/efeitos dos fármacos , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Tiazolidinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
13.
J Perianesth Nurs ; 36(2): 157-161, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33229169

RESUMO

PURPOSE: The purpose of this pilot study was to determine the efficacy of a proactive laxative protocol for constipation prevention in patients undergoing uterine artery embolization (UAE). DESIGN: A nonrandomized clinical trial. METHODS: A nonrandomized trial study design was piloted using a convenience sample of 35 patients undergoing UAE in the course of 1 year. FINDINGS: There was a statistically significant difference (P < .0001) in time of first bowel movement after UAE when patients followed a proactive laxative protocol. A combination of senna and stool softener taken twice a day for 2 days preoperatively was associated with a shorter time to first bowel movement postoperatively. CONCLUSIONS: This pilot study supports the benefits of a proactive laxative protocol in helping achieve procedural recovery uncomplicated by constipation in patients undergoing UAE.


Assuntos
Laxantes , Embolização da Artéria Uterina , Protocolos Clínicos , Feminino , Humanos , Laxantes/uso terapêutico , Projetos Piloto , Resultado do Tratamento
14.
J Perianesth Nurs ; 36(2): 128-135, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33218877

RESUMO

PURPOSE: The purpose of this study was to identify current individual practice of perianesthesia nurses regarding assessment and documentation of pain. DESIGN: Descriptive cross-sectional design using vignette technique. METHODS: Vignettes with questions available via electronic survey offered to attendees of the 2017 American Society of PeriAnesthesia Nurses National Conference. FINDINGS: Total of 1,680 perianesthesia nurses participated; 41.4% reported assessment of pain compared with 36.7% who reported documentation of pain assessment. The numeric (0 to 10) pain intensity score was the most commonly used assessment method. Only 16.4% assessed for and documented pain location, 14.4% assessed for and documented quality of pain. CONCLUSIONS: Pain assessment should include intensity, location, quality, and functional impact. The gap between nurses' practices in assessment and documention of pain may be related to system barriers. Embedding evidence-based best practice within electronic health records may improve both. Prior literature, as well as our findings, indicate these trends (missed documentation and assessment) are more global than only perianesthesia nursing.


Assuntos
Manejo da Dor , Enfermagem Perioperatória , Estudos Transversais , Documentação , Humanos , Medição da Dor , Estados Unidos
15.
Ann Surg Oncol ; 27(13): 4908-4917, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32409962

RESUMO

BACKGROUND: Low-grade appendiceal mucinous neoplasms (LAMN) are tumors that frequently present with peritoneal spread of either acellular mucin (AM) or cellular mucin (CM). We aim to determine how mucin types and distribution affect survival. PATIENTS AND METHODS: A retrospective cohort study was conducted using a prospective database. Newly diagnosed LAMN patients with AM versus CM treated with cytoreductive surgery/hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) were compared. Postoperative pathology reports were reviewed to assess each involved abdominal zone. Survival was analyzed using the Kaplan-Meier method. RESULTS: Of 121 identified patients, 50 (41%) had peritoneal lesions with AM and 71 (59%) with CM. Peritoneal cancer index was lower in AM versus CM (mean: 19 ± 13 vs 28 ± 10, p = 0.004), but complete cytoreduction (CC) rates were similar (98% vs 96%, p = 0.642). The 5-year progression-free survival (PFS) was higher in AM versus CM (96% vs 69.8%, p = 0.002). CM patients had zones with both types of lesions: with and without cells. The CM subgroup analysis showed significant differences in 5-year progression-free survival (PFS) among patients with 1-3, 4-7, and 8-10 zones with cells (95.2%, 68.4%, and 35.7%, respectively, p < 0.001), but PFS was not affected by the number of zones with any lesion type. There was no difference in overall survival (OS) between groups. CONCLUSIONS: Despite comparable CC rates after CRS/HIPEC, CM patients have shorter PFS than AM patients. In CM patients, more zones with cells, but not the total number of involved zones, negatively impact PFS. Mucin type does not impact OS. It is important to assess and report mucin cellularity in LAMN specimens.


Assuntos
Neoplasias do Apêndice , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Apêndice/terapia , Procedimentos Cirúrgicos de Citorredução , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Mucinas , Neoplasias Peritoneais/terapia , Estudos Retrospectivos , Taxa de Sobrevida
16.
Ann Surg Oncol ; 27(13): 5026-5036, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32705513

RESUMO

BACKGROUND: The completeness of cytoreduction (CC) score, which quantifies residual tumor, is a major prognostic factor when treating appendiceal carcinomatosis with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Both CC-0 and CC-1 are considered complete cytoreductions (CC-0/1) and associated with the best outcomes. We analyzed if the CC-0/1 definition is reliable across appendiceal histopathologic subtypes. METHODS: A prospective database of CRS/HIPEC patients with appendiceal carcinomatosis from 1998 to 2019 was reviewed to identify patients with CC-0/1. Kaplan-Meier overall survival (OS) and progression-free survival (PFS) by CC-score for each histopathology were calculated. RESULTS: Overall, 297 patients had CC-0/1. Mean age was 54 ± 12 years with 67% females. Histopathologic subtypes were 45% low-grade mucinous carcinoma peritonei (LGMCP), 27% high-grade MCP (HGMCP), 20% HGMCP with signet ring cells (HGMCP-S), and 8% goblet cell adenocarcinoma (GCAC). CC-0 and CC-1 occurred in 57% and 43% of LGMCP, 65% and 35% of HGMCP, 68% and 32% of HGMCP-S, and 79% and 21% of GCAC, respectively. OS and PFS were statistically longer for CC-0 versus CC-1 in HGMCP-S (p = 0.001 and p = 0.005, respectively) and GCAC (p < 0.001 and p < 0.001), but not in LGMCP (p = 0.098 and p = 0.398) or HGMCP (p = 0.167 and p = 0.356). CONCLUSIONS: Survival outcomes for CC-0 and CC-1 after CRS/HIPEC are different for HGMCP-S and GCAC but not for LGMCP and HGMCP. In HGCMP-S and GCAC, only CC-0 should be considered a complete cytoreduction and analyzed separately from CC-1. This distinction is key to understand disease behavior, accurately address patient prognosis, and explore new treatment strategies.


Assuntos
Quimioterapia Intraperitoneal Hipertérmica , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Apêndice/tratamento farmacológico , Procedimentos Cirúrgicos de Citorredução , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
17.
Glia ; 67(7): 1401-1411, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30924555

RESUMO

Cell shape is critical for the proper function of every cell in every tissue in the body. This is especially true for the highly morphologically diverse neural and glia cells of the central nervous system. The molecular processes by which these, or indeed any, cells gain their particular cell-specific morphology remain largely unexplored. To identify the genes involved in the morphogenesis of the principal glial cell type in the vertebrate retina, the Müller glia (MG), we used genomic and CRISPR based strategies in zebrafish (Danio rerio). We identified 41 genes involved in various aspects of MG cell morphogenesis and revealed a striking concordance between the sequential steps of anatomical feature addition and the expression of cohorts of functionally related genes that regulate these steps. We noted that the many of the genes preferentially expressed in zebrafish MG showed conservation in glia across species suggesting evolutionarily conserved glial developmental pathways.


Assuntos
Células Ependimogliais/fisiologia , Perfilação da Expressão Gênica/métodos , Morfogênese/fisiologia , Neurogênese/fisiologia , Neuroglia/fisiologia , Transcriptoma/fisiologia , Animais , Animais Geneticamente Modificados , Diferenciação Celular/fisiologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/fisiologia , Peixe-Zebra
18.
Ann Surg Oncol ; 26(7): 2268-2275, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31041628

RESUMO

BACKGROUND: Survival in peritoneal dissemination from appendiceal cancer after complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) varies within each histopathologic subtype. Analyzing patients with unique responses may uncover the mechanisms behind their extreme outcomes. We proposed a method to identify retrospectively and to characterize patients who responded exceptionally well or very poorly within each histopathologic subtype. METHODS: Retrospective review of patients with low-grade mucinous carcinoma peritonei (LGMCP), high-grade MCP (HGMCP), and HGMCP with signet ring cells (HGMCP-S) with complete CRS/HIPEC (CC-0/1) was performed. Patients were divided by recurrence status. Median follow-up was calculated for each. Exceptional responders (ExR) were defined as alive without recurrence after median follow-up of the nonrecurrent group. Poor responders (PoR) were defined as disease recurrence before median follow-up of the recurrent group. Perioperative characteristics were analyzed. RESULTS: LGMCP, HGMCP, and HGMCP-S had 48 (41%), 19 (23%), and 7 (14%) ExR and 11 (10%), 20 (24%), and 20 (39%) PoR, respectively. All ExR had lower median PCI (26 vs. 36 [p = 0.004]; 13 vs. 33.5 [p < 0.001]; 3 vs. 29.5 [p = 0.001]). Fewer LGMCP and HGMCP ExR had abnormal tumor markers (36% vs. 90% [p = 0.003]; 22% vs. 74% [p = 0.003]). More HGMCP and HGMCP-S ExR had CC-0 (vs. CC-1) cytoreductions (84% vs. 50%, p = 0.041; 100% vs. 40%, p = 0.008). CONCLUSIONS: Stratifying patients by recurrence status and follow-up time successfully selects ExR and PoR within each histopathologic subtype. Perioperative characteristics of ExR versus PoR differ across histopathologic subtypes, except for disease burden. Genetic analysis may further elucidate differences and aid in the development of novel targeted therapies.


Assuntos
Neoplasias do Apêndice/mortalidade , Quimioterapia do Câncer por Perfusão Regional/mortalidade , Procedimentos Cirúrgicos de Citorredução/mortalidade , Hipertermia Induzida/mortalidade , Seleção de Pacientes , Neoplasias Peritoneais/mortalidade , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/terapia , Neoplasias do Apêndice/patologia , Neoplasias do Apêndice/terapia , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/terapia , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/terapia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida
19.
Ann Surg Oncol ; 26(2): 473-481, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30523470

RESUMO

BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is standard treatment for peritoneal dissemination from appendiceal cancer (AC); however, its role in high-grade histopathologic subtypes (high-grade mucinous carcinoma peritonei [HGMCP] and HGMCP with signet ring cells [HGMCP-S]) is controversial due to their aggressive behavior. This study analyzed clinical outcomes of high-grade AC after CRS/HIPEC. METHODS: A prospective database of CRS/HIPEC procedures for HGMCP performed from 1998-2017 was reviewed. Perioperative variables and survival were analyzed. RESULTS: Eighty-six HGMCP and 65 HGMCP-S were identified. HGMCP had more positive tumor markers (TM) (CEA/CA-125/CA-19-9) than HGMCP-S (63% vs 40%, p = 0.005). HGMCP had higher Peritoneal Cancer Index (32 vs 26, p = 0.097) and was less likely to have positive lymph nodes (LN) than HGMCP-S (28% vs 69%, p = < 0.001). Complete cytoreduction was achieved in 84% and 83%, respectively. PFS at 3- and 5-years was 59% and 48% for HGMCP vs 31% and 14% for HGMCP-S. Median PFS was 4.3 and 1.6 years, respectively (p < 0.001). OS at 3- and 5-years was 84% and 64% in HGMCP vs 38% and 25% in HGMCP-S. Median OS was 7.5 and 2.2 years, respectively (p < 0.001). LN negative HGMCP-S had longer median PFS and OS than LN positive HGMCP-S (PFS: 3.4 vs 1.5 years, p = 0.03; OS: 5.6 vs 2.1 months, p = 0.021). CONCLUSIONS: The aggressive histology of HGMCP-S is associated with poor OS, has fewer abnormal TM, and is more likely to have positive LN. However, CRS/HIPEC can achieve a 5-year survival of 25%, which may improve to 51% with negative LN.


Assuntos
Neoplasias do Apêndice/mortalidade , Carcinoma de Células em Anel de Sinete/mortalidade , Quimioterapia do Câncer por Perfusão Regional/mortalidade , Procedimentos Cirúrgicos de Citorredução/mortalidade , Hipertermia Induzida/mortalidade , Recidiva Local de Neoplasia/mortalidade , Neoplasias Peritoneais/mortalidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Apêndice/patologia , Neoplasias do Apêndice/terapia , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/terapia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
20.
PLoS Genet ; 12(4): e1005984, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27070787

RESUMO

The Notch pathway controls proliferation during development and in adulthood, and is frequently affected in many disorders. However, the genetic sensitivity and multi-layered transcriptional properties of the Notch pathway has made its molecular decoding challenging. Here, we address the complexity of Notch signaling with respect to proliferation, using the developing Drosophila CNS as model. We find that a Notch/Su(H)/E(spl)-HLH cascade specifically controls daughter, but not progenitor proliferation. Additionally, we find that different E(spl)-HLH genes are required in different neuroblast lineages. The Notch/Su(H)/E(spl)-HLH cascade alters daughter proliferation by regulating four key cell cycle factors: Cyclin E, String/Cdc25, E2f and Dacapo (mammalian p21CIP1/p27KIP1/p57Kip2). ChIP and DamID analysis of Su(H) and E(spl)-HLH indicates direct transcriptional regulation of the cell cycle genes, and of the Notch pathway itself. These results point to a multi-level signaling model and may help shed light on the dichotomous proliferative role of Notch signaling in many other systems.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sistema Nervoso Central/embriologia , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Receptores Notch/metabolismo , Proteínas Repressoras/metabolismo , Animais , Sítios de Ligação/genética , Comunicação Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem da Célula , Proliferação de Células/genética , Ciclina E/metabolismo , Drosophila/genética , Drosophila/metabolismo , Fatores de Transcrição E2F/metabolismo , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Transdução de Sinais , Fatores de Transcrição , Transcrição Gênica/genética , Ativação Transcricional/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA