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1.
Cell Rep Med ; 5(1): 101359, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38232702

RESUMO

Acute myeloid leukemia is a poor-prognosis cancer commonly stratified by genetic aberrations, but these mutations are often heterogeneous and fail to consistently predict therapeutic response. Here, we combine transcriptomic, proteomic, and phosphoproteomic datasets with ex vivo drug sensitivity data to help understand the underlying pathophysiology of AML beyond mutations. We measure the proteome and phosphoproteome of 210 patients and combine them with genomic and transcriptomic measurements to identify four proteogenomic subtypes that complement existing genetic subtypes. We build a predictor to classify samples into subtypes and map them to a "landscape" that identifies specific drug response patterns. We then build a drug response prediction model to identify drugs that target distinct subtypes and validate our findings on cell lines representing various stages of quizartinib resistance. Our results show how multiomics data together with drug sensitivity data can inform therapy stratification and drug combinations in AML.


Assuntos
Leucemia Mieloide Aguda , Proteogenômica , Humanos , Proteômica/métodos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Genômica/métodos , Mutação
2.
Am J Clin Pathol ; 161(2): 170-176, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37904278

RESUMO

OBJECTIVES: Determination of bone marrow cellularity is a key part of bone marrow examination because it provides a small window into a patient's current state of hematopoietic well-being. Traditionally, bone marrow cellularity is estimated semiquantitatively through microscopic examination of core biopsy specimens harvested from the iliac crest of the pelvic bone. Bone marrow cellularity is then designated as hypercellular, normocellular, or hypocellular based on the patient's age. This assessment can have significant clinical impact, but the variation in the age-adjusted normocellularity range is not sufficiently characterized because of a lack of study data, especially in older patients (those older than 70 years of age). This study further established the normal range of bone marrow cellularity, particularly in older adults. METHODS: In this study, 570 benign staging and healthy donor bone marrows from patients 1 year to 93 years of age were analyzed for cellularity. RESULTS: Linear regression modeling demonstrates that cellularity in adults declines approximately 3% per decade, including after the seventh decade of life. The 90% reference interval for normocellularity in United States is 30% to 75% for those aged 18 to 90 years. CONCLUSIONS: The findings revealed a more stable and slower rate of decline in cellularity with age in adults than the widely used linear model of "100% minus the patient age in decades." Normocellularity is better modeled based on age group. In those younger than 20 years of age, normocellularity ranges from 45% to 85% (mean [SD], 65% [20%]), as defined by Friebert et al in 1998. Based on our study finding of a little less than 3% decline per decade of age, the following is our recommendation for normocellularity range: For individuals 20 to 40 years of age, it ranges from 40% to 70% (mean [SD], 55% [15%]); for individuals 40 to 60 years of age, it ranges from 35% to 65% (mean [SD], 50% [15%]); and for individuals older than 60 years of age, it ranges from 30% to 60% (mean [SD], 45% [15%]). Interestingly, those older than 70 years of age do not show a significant decrease from those aged 60 to 69 years.


Assuntos
Células da Medula Óssea , Medula Óssea , Humanos , Idoso , Adulto Jovem , Adulto , Lactente , Medula Óssea/patologia , Exame de Medula Óssea , Células da Medula Óssea/patologia , Biópsia com Agulha de Grande Calibre , Hiperplasia/patologia
3.
Ann Med ; 55(1): 2208372, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37722890

RESUMO

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and fibromyalgia have overlapping neurologic symptoms particularly disabling fatigue. This has given rise to the question whether they are distinct central nervous system (CNS) entities or is one an extension of the other. MATERIAL AND METHODS: To investigate this, we used unbiased quantitative mass spectrometry-based proteomics to examine the most proximal fluid to the brain, cerebrospinal fluid (CSF). This was to ascertain if the proteome profile of one was the same or different from the other. We examined two separate groups of ME/CFS, one with (n = 15) and one without (n = 15) fibromyalgia. RESULTS: We quantified a total of 2083 proteins using immunoaffinity depletion, tandem mass tag isobaric labelling and offline two-dimensional liquid chromatography coupled to tandem mass spectrometry, including 1789 that were quantified in all the CSF samples. ANOVA analysis did not yield any proteins with an adjusted p value <.05. CONCLUSION: This supports the notion that ME/CFS and fibromyalgia as currently defined are not distinct entities.Key messageME/CFS and fibromyalgia as currently defined are not distinct entities.Unbiased quantitative mass spectrometry-based proteomics can be used to discover cerebrospinal fluid proteins that are biomarkers for a condition such as we are studying.


Assuntos
Síndrome de Fadiga Crônica , Fibromialgia , Humanos , Proteoma , Síndrome de Fadiga Crônica/diagnóstico , Fibromialgia/diagnóstico , Sistema Nervoso Central , Encéfalo
4.
Perm J ; 27(1): 88-93, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36880200

RESUMO

Introduction Radiation safety training remains variable among gastroenterologists performing endoscopic retrograde cholangiopancreatography (ERCP). This study sought to ascribe dosimeter readings to various real-world ERCP scenarios to provide data supporting the 3 pillars of radiation safety: distance, time, and shielding. Methods An ERCP fluoroscopy unit was used to generate radiation scatter from 2 differently sized anthropomorphic phantoms. Radiation scatter was measured at various distances from the emitter, with and without a lead apron, and at various frame rates (measured in frames per second, fps) and degrees of fluoroscopy pedal actuation. An image quality phantom was used to assess resolution at various frame rates and air gaps. Results Increasing the distance resulted in a decrease in measured scatter (from 0.75 mR/h at 1.5 ft to 0.15 mR/h at 9 ft with the average phantom and from 50 mR/h at 1.5 ft to 3.06 mR/h at 9 ft with the large phantom). Depressing the fluoroscopy pedal less frequently, or decreasing the frame rate (ie, increasing the time per frame), resulted in a linear decrease in scatter (from 55 mR/h at 8 fps to 24.5 mR/h at 4 fps and 13.60 mR/h at 2 fps). Providing shielding through the presence of a 0.5-mm lead apron reduced scatter (from 4.10 to 0.11 mR/h with the average phantom; from 15.30 mR/h to 0.43 mR/h with the large phantom). However, decreasing the frame rate from 8 fps to 2 fps did not change the number of line pairs identified on the image phantom. A greater air gap increased the number of line pairs resolved. Conclusions Implementing the 3 pillars of radiation safety led to a quantifiable, clinically significant decrease in radiation scatter. The authors hope that these findings spark greater implementation of radiation safety measures among practitioners utilizing fluoroscopy.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Proteção Radiológica , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Doses de Radiação , Proteção Radiológica/métodos , Fluoroscopia/efeitos adversos , Imagens de Fantasmas
5.
Diabetol Metab Syndr ; 14(1): 148, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229864

RESUMO

BACKGROUND: Diabetes-induced liver injury is a complication of diabetes mellitus of which there are no approved drugs for effective treatment or prevention. This study investigates possible hepatoprotective effect of alpha-lipoic acid (ALA), and sulfane sulfur/hydrogen sulfide pathway as a novel protective mechanism in a rat model of type 2 diabetes-induced liver injury. METHODS: Thirty Sprague-Dawley rats underwent fasting for 12 h after which fasting blood glucose was measured and rats were randomly assigned to diabetic and non-diabetic groups. Type 2 diabetes mellitus (T2DM) was induced in diabetic group by administration of nicotinamide (110 mg/kg) and streptozotocin (55 mg/kg). Diabetic rats were treated daily with ALA (60 mg/kg/day p.o.) or 40 mg/kg/day DL-propargylglycine (PPG, an inhibitor of endogenous hydrogen sulfide production) for 6 weeks and then sacrificed. Liver, pancreas and blood samples were collected for analysis. Untreated T2DM rats received distilled water. RESULTS: Hypoinsulinemia, hyperglycemia, hepatomegaly and reduced hepatic glycogen content were observed in untreated T2DM rats compared to healthy control group (p < 0.001). Also, the pancreas of untreated T2DM rats showed severely damaged pancreatic islets while liver damage was characterized by markedly increased hepatocellular vacuolation, sinusoidal enlargement, abnormal intrahepatic lipid accumulation, severe transaminitis, hyperbilirubinemia, and impaired hepatic antioxidant status and inflammation compared to healthy control rats (p < 0.01). While pharmacological inhibition of hepatic sulfane sulfur/hydrogen sulfide with PPG administration aggravated these pathological changes (p < 0.05), ALA strongly prevented these changes. ALA also significantly increased hepatic expression of hydrogen sulfide-producing enzymes (cystathionine γ-lyase and 3-mecaptopyruvate sulfurtransferase) as well as hepatic sulfane sulfur and hydrogen sulfide levels compared to all groups (p < 0.01). CONCLUSIONS: To the best of our knowledge, this is the first experimental evidence showing that ALA prevents diabetes-induced liver injury by activating hepatic sulfane sulfur/hydrogen sulfide pathway via upregulation of hepatic cystathionine γ-lyase and 3-mecaptopyruvate sulfurtransferase expressions. Therefore, ALA could serve as a novel pharmacological agent for the treatment and prevention of diabetes-induced liver injury, with hepatic sulfane sulfur/hydrogen sulfide as a novel therapeutic target.

6.
Nat Commun ; 13(1): 5429, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114177

RESUMO

Controlling thermal transport is important for a range of devices and technologies, from phase change memories to next-generation electronics. This is especially true in nano-scale devices where thermal transport is altered by the influence of surfaces and changes in dimensionality. In superconducting nanowire single-photon detectors, the thermal boundary conductance between the nanowire and the substrate it is fabricated on influences all of the performance metrics that make these detectors attractive for applications. This includes the maximum count rate, latency, jitter, and quantum efficiency. Despite its importance, the study of thermal boundary conductance in superconducting nanowire devices has not been done systematically, primarily due to the lack of a straightforward characterization method. Here, we show that simple electrical measurements can be used to estimate the thermal boundary conductance between nanowires and substrates and that these measurements agree with acoustic mismatch theory across a variety of substrates. Numerical simulations allow us to refine our understanding, however, open questions remain. This work should enable thermal engineering in superconducting nanowire electronics and cryogenic detectors for improved device performance.

7.
Redox Biol ; 55: 102405, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35872399

RESUMO

Preterm infants and patients with lung disease often have excess fluid in the lungs and are frequently treated with oxygen, however long-term exposure to hyperoxia results in irreversible lung injury. Although the adverse effects of hyperoxia are mediated by reactive oxygen species, the full extent of the impact of hyperoxia on redox-dependent regulation in the lung is unclear. In this study, neonatal mice overexpressing the beta-subunit of the epithelial sodium channel (ß-ENaC) encoded by Scnn1b and their wild type (WT; C57Bl6) littermates were utilized to study the pathogenesis of high fraction inspired oxygen (FiO2)-induced lung injury. Results showed that O2-induced lung injury in transgenic Scnn1b mice is attenuated following chronic O2 exposure. To test the hypothesis that reversible cysteine-redox-modifications of proteins play an important role in O2-induced lung injury, we performed proteome-wide profiling of protein S-glutathionylation (SSG) in both WT and Scnn1b overexpressing mice maintained at 21% O2 (normoxia) or FiO2 85% (hyperoxia) from birth to 11-15 days postnatal. Over 7700 unique Cys sites with SSG modifications were identified and quantified, covering more than 3000 proteins in the lung. In both mouse models, hyperoxia resulted in a significant alteration of the SSG levels of Cys sites belonging to a diverse range of proteins. In addition, substantial SSG changes were observed in the Scnn1b overexpressing mice exposed to hyperoxia, suggesting that ENaC plays a critically important role in cellular regulation. Hyperoxia-induced SSG changes were further supported by the results observed for thiol total oxidation, the overall level of reversible oxidation on protein cysteine residues. Differential analyses reveal that Scnn1b overexpression may protect against hyperoxia-induced lung injury via modulation of specific processes such as cell adhesion, blood coagulation, and proteolysis. This study provides a landscape view of protein oxidation in the lung and highlights the importance of redox regulation in O2-induced lung injury.


Assuntos
Hiperóxia , Lesão Pulmonar , Humanos , Recém-Nascido , Animais , Camundongos , Hiperóxia/complicações , Hiperóxia/genética , Hiperóxia/metabolismo , Lesão Pulmonar/genética , Lesão Pulmonar/metabolismo , Cisteína/metabolismo , Recém-Nascido Prematuro , Pulmão/metabolismo , Oxirredução , Oxigênio , Proteínas/metabolismo , Camundongos Transgênicos , Animais Recém-Nascidos
8.
Biomed Pharmacother ; 153: 113386, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35834985

RESUMO

INTRODUCTION: We previously reported that alpha-lipoic acid (ALA) supplementation protects against progression of diabetic kidney disease (DKD). In this study, we aim to investigate whether the mechanism of renal protection by ALA involves renal cystathionine γ-lyase/hydrogen sulfide (CSE/H2S) system in type 2 diabetes mellitus (T2DM). METHODS: Thirty-seven male Sprague-Dawley rats underwent 12 h of overnight fasting. To induce T2DM, 30 of these rats received intraperitoneal administration of nicotinamide (110 mg/kg) and streptozotocin (55 mg/kg). T2DM rats then received either oral administration of ALA (60 mg/kg/day) or intraperitoneal administration of 40 mg/kg/day DL-propargylglycine (PAG, a CSE inhibitor) or both for 6 weeks after which rats were sacrificed and samples collected for analysis. Untreated diabetic and non-diabetic rats served as diabetic and healthy controls respectively. RESULTS: T2DM was characterized by reduced pancreatic ß-cell function and hyperglycemia. Histologically, untreated diabetic rats showed significantly damaged pancreatic islets, glomerular and tubular injury, with elevated levels of renal function markers compared to healthy control rats (p < 0.001). These pathological changes worsened significantly following PAG administration (p < 0.05). While some renal protection was observed in ALA+PAG rats, ALA administration in untreated diabetic rats provided superior protection comparable to healthy control rats, with improved antioxidant status, lipid profile and reduced inflammation. Mechanistically, ALA significantly activated renal CSE/H2S system in diabetic rats, which was markedly suppressed in PAG-treated rats (p < 0.001). CONCLUSION: Our data suggest that ALA protects against DKD development and progression by activating renal CSE/H2S pathway. Hence, CSE/H2S pathway may represent a therapeutic target in the treatment or prevention of DKD in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Sulfeto de Hidrogênio , Ácido Tióctico , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/prevenção & controle , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Rim/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico
9.
Clin Proteomics ; 19(1): 30, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896960

RESUMO

Acute Myeloid Leukemia (AML) affects 20,000 patients in the US annually with a five-year survival rate of approximately 25%. One reason for the low survival rate is the high prevalence of clonal evolution that gives rise to heterogeneous sub-populations of leukemic cells with diverse mutation spectra, which eventually leads to disease relapse. This genetic heterogeneity drives the activation of complex signaling pathways that is reflected at the protein level. This diversity makes it difficult to treat AML with targeted therapy, requiring custom patient treatment protocols tailored to each individual's leukemia. Toward this end, the Beat AML research program prospectively collected genomic and transcriptomic data from over 1000 AML patients and carried out ex vivo drug sensitivity assays to identify genomic signatures that could predict patient-specific drug responses. However, there are inherent weaknesses in using only genetic and transcriptomic measurements as surrogates of drug response, particularly the absence of direct information about phosphorylation-mediated signal transduction. As a member of the Clinical Proteomic Tumor Analysis Consortium, we have extended the molecular characterization of this cohort by collecting proteomic and phosphoproteomic measurements from a subset of these patient samples (38 in total) to evaluate the hypothesis that proteomic signatures can improve the ability to predict response to 26 drugs in AML ex vivo samples. In this work we describe our systematic, multi-omic approach to evaluate proteomic signatures of drug response and compare protein levels to other markers of drug response such as mutational patterns. We explore the nuances of this approach using two drugs that target key pathways activated in AML: quizartinib (FLT3) and trametinib (Ras/MEK), and show how patient-derived signatures can be interpreted biologically and validated in cell lines. In conclusion, this pilot study demonstrates strong promise for proteomics-based patient stratification to assess drug sensitivity in AML.

10.
ACS Nano ; 16(8): 12930-12940, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35849731

RESUMO

Short-wave infrared (SWIR; 850-1700 nm) upconversion fluorescence enables "autofluorescence-free" imaging with minimal tissue scattering, yet it is rarely explored due to the lack of strongly emissive SWIR upconversion fluorophores. In this work, we apply SWIR upconversion fluorescence for in vivo imaging with exceptional image contrast. Gold nanorods (AuNRs) are used to enhance the SWIR upconversion emission of small organic dyes, forming a AuNR-dye nanocomposite (NC). A maximal enhancement factor of ∼1320, contributed by both excitation and radiative decay rate enhancement, is achieved by varying the dye-to-AuNR ratio. In addition, the upconversion emission intensity of both free dyes and AuNR-dye NCs depends linearly on the excitation power, indicating that the upconversion emission mechanism remains unchanged upon enhancement, and it involves one-photon absorption. Moreover, the SWIR upconversion emission shows a significantly higher signal contrast than downconversion emission in the same emission window in a nonscattering medium. Finally, we apply the surface plasmon enhanced SWIR upconversion fluorescence for in vivo imaging of ovarian cancer, demonstrating high image contrast and low required dosage due to the suppressed autofluorescence.


Assuntos
Corantes Fluorescentes , Neoplasias Ovarianas , Humanos , Feminino , Fluorescência , Ouro , Diagnóstico por Imagem , Neoplasias Ovarianas/diagnóstico por imagem
11.
Nitric Oxide ; 120: 16-25, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35032641

RESUMO

The novel coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, is a global pandemic which is primarily considered a respiratory illness. However, emerging reports show that the virus exhibits both pulmonary and extra-pulmonary manifestations in humans, with the kidney as a major extra-pulmonary target due to its abundant expression of angiotensin-converting enzyme 2 and transmembrane protease serine 2, which facilitate entry of the virus into cells. Acute kidney injury has become prevalent in COVID-19 patients without prior any history of kidney dysfunction. In addition, the virus also worsens kidney conditions and increases mortality of COVID-19 patients with pre-existing chronic kidney disease, renal cancer, diabetic nephropathy, end-stage kidney disease as well as dialysis and kidney transplant patients. In the search for antiviral agents for the treatment of COVID-19, hydrogen sulfide (H2S), the third established member of gasotransmitter family, is emerging as a potential candidate, possessing important therapeutic properties including antiviral, anti-inflammatory, anti-thrombotic and antioxidant properties. A recent clinical study revealed higher serum H2S levels in survivors of COVID-19 pneumonia with reduced interleukin-6 levels compared to fatal cases. In this review, we summarize the global impact of COVID-19 on kidney conditions and discuss the emerging role of H2S as a potential COVID-19 therapy.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Sulfeto de Hidrogênio/farmacologia , Nefropatias/tratamento farmacológico , SARS-CoV-2/efeitos dos fármacos , Antivirais/química , COVID-19/virologia , Humanos , Sulfeto de Hidrogênio/química , Nefropatias/virologia
12.
J Am Soc Mass Spectrom ; 33(1): 17-30, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34813325

RESUMO

Global and phosphoproteome profiling has demonstrated great utility for the analysis of clinical specimens. One barrier to the broad clinical application of proteomic profiling is the large amount of biological material required, particularly for phosphoproteomics─currently on the order of 25 mg wet tissue weight. For hematopoietic cancers such as acute myeloid leukemia (AML), the sample requirement is ≥10 million peripheral blood mononuclear cells (PBMCs). Across large study cohorts, this requirement will exceed what is obtainable for many individual patients/time points. For this reason, we were interested in the impact of differential peptide loading across multiplex channels on proteomic data quality. To achieve this, we tested a range of channel loading amounts (approximately the material obtainable from 5E5, 1E6, 2.5E6, 5E6, and 1E7 AML patient cells) to assess proteome coverage, quantification precision, and peptide/phosphopeptide detection in experiments utilizing isobaric tandem mass tag (TMT) labeling. As expected, fewer missing values were observed in TMT channels with higher peptide loading amounts compared to lower loadings. Moreover, channels with a lower loading have greater quantitative variability than channels with higher loadings. A statistical analysis showed that decreased loading amounts result in an increase in the type I error rate. We then examined the impact of differential loading on the detection of known differences between distinct AML cell lines. Similar patterns of increased data missingness and higher quantitative variability were observed as loading was decreased resulting in fewer statistical differences; however, we found good agreement in features identified as differential, demonstrating the value of this approach.


Assuntos
Fosfopeptídeos , Proteômica/métodos , Proteômica/normas , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/normas , Células Cultivadas , Cromatografia de Afinidade , Confiabilidade dos Dados , Humanos , Marcação por Isótopo , Leucócitos Mononucleares/química , Fosfopeptídeos/análise , Fosfopeptídeos/química , Fosfopeptídeos/isolamento & purificação
13.
Stem Cell Reports ; 16(10): 2442-2458, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34534448

RESUMO

Skeletal muscle satellite cells (SCs) are stem cells responsible for muscle development and regeneration. Although CRISPR/Cas9 has been widely used, its application in endogenous SCs remains elusive. Here, we generate mice expressing Cas9 in SCs and achieve robust editing in juvenile SCs at the postnatal stage through AAV9-mediated short guide RNA (sgRNA) delivery. Additionally, we reveal that quiescent SCs are resistant to CRISPR/Cas9-mediated editing. As a proof of concept, we demonstrate efficient editing of master transcription factor (TF) Myod1 locus using the CRISPR/Cas9/AAV9-sgRNA system in juvenile SCs. Application on two key TFs, MYC and BCL6, unveils distinct functions in SC activation and muscle regeneration. Particularly, we reveal that MYC orchestrates SC activation through regulating 3D genome architecture. Its depletion results in strengthening of the topologically associating domain boundaries thus may affect gene expression. Altogether, our study establishes a platform for editing endogenous SCs that can be harnessed to elucidate the functionality of key regulators governing SC activities.


Assuntos
Cromatina/metabolismo , Genes myc , Genoma , Proteína MyoD/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , RNA Guia de Cinetoplastídeos/metabolismo , Células Satélites de Músculo Esquelético/fisiologia , Animais , Sistemas CRISPR-Cas , Edição de Genes/métodos , Regulação da Expressão Gênica , Camundongos , Proteína MyoD/genética , Conformação de Ácido Nucleico , Proteínas Proto-Oncogênicas c-bcl-6/genética , RNA Guia de Cinetoplastídeos/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
J Insect Physiol ; 133: 104286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34293336

RESUMO

Many aquatic insects use bubbles on the body surface to store and supply O2 for their dives. There are two types of bubbles: air stores, which store O2 gained from air at the surface, and gas gills that allow passive extraction of O2 from water. Many insects using air stores and gas gills return to the surface to replenish their bubbles and, therefore, their requirement for O2 influences dive behaviour. In this study, we investigate gas exchange and dive behaviour in the diving beetle Platynectes decempunctatus that uses a sub-elytral air store and a small compressible gas gill. We measure the PO2 within the air store during tethered dives, as well as the amount of O2 exchanged during surfacing events. Buoyancy experiments monitor the volume of gas in the gas gill and how it changes during dives. We also directly link O2-consumption rate at three temperatures (10, 15 and 20 °C) with dive duration, surfacing frequency and movement activity. These data are incorporated in a gas exchange model, which shows that the small gas gill of P. decempunctatus contributes less than 10% of the total O2 used during the dive, while up to 10% is supplied by cutaneous uptake.


Assuntos
Besouros/fisiologia , Animais , Mergulho , Gases/metabolismo , Transporte Respiratório/fisiologia
15.
Cancer Cell ; 39(7): 999-1014.e8, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34171263

RESUMO

Our study details the stepwise evolution of gilteritinib resistance in FLT3-mutated acute myeloid leukemia (AML). Early resistance is mediated by the bone marrow microenvironment, which protects residual leukemia cells. Over time, leukemia cells evolve intrinsic mechanisms of resistance, or late resistance. We mechanistically define both early and late resistance by integrating whole-exome sequencing, CRISPR-Cas9, metabolomics, proteomics, and pharmacologic approaches. Early resistant cells undergo metabolic reprogramming, grow more slowly, and are dependent upon Aurora kinase B (AURKB). Late resistant cells are characterized by expansion of pre-existing NRAS mutant subclones and continued metabolic reprogramming. Our model closely mirrors the timing and mutations of AML patients treated with gilteritinib. Pharmacological inhibition of AURKB resensitizes both early resistant cell cultures and primary leukemia cells from gilteritinib-treated AML patients. These findings support a combinatorial strategy to target early resistant AML cells with AURKB inhibitors and gilteritinib before the expansion of pre-existing resistance mutations occurs.


Assuntos
Compostos de Anilina/farmacologia , Aurora Quinase B/metabolismo , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Pirazinas/farmacologia , Microambiente Tumoral , Aurora Quinase B/genética , Biomarcadores Tumorais/genética , Exoma , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Metaboloma , Inibidores de Proteínas Quinases/farmacologia , Proteoma , Células Tumorais Cultivadas
16.
J Appl Clin Med Phys ; 22(7): 128-136, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34042253

RESUMO

PURPOSE: Electron radiation therapy dose distributions are affected by irregular body surface contours. This study investigates the feasibility of three-dimensional (3D) cameras to substitute for the treatment planning computerized tomography (CT) scan by capturing the body surfaces to be treated for accurate electron beam dosimetry. METHODS: Dosimetry was compared for six electron beam treatments to the nose, toe, eye, and scalp using full CT scan, CT scan with Hounsfield Unit (HU) overridden to water (mimic 3D camera cases), and flat-phantom techniques. Radiation dose was prescribed to a depth on the central axis per physician's order, and the monitor units (MUs) were calculated. The 3D camera spatial accuracy was evaluated by comparing the 3D surface of a head phantom captured by a 3D camera and that generated with the CT scan in the treatment planning system. A clinical case is presented, and MUs were calculated using the 3D camera body contour with HU overridden to water. RESULTS: Across six cases the average change in MUs between the full CT and the 3Dwater (CT scan with HU overridden to water) calculations was 1.3% with a standard deviation of 1.0%. The corresponding hotspots had a mean difference of 0.4% and a standard deviation of 1.9%. The 3D camera captured surface of a head phantom was found to have a 0.59 mm standard deviation from the surface derived from the CT scan. In-vivo dose measurements (213 ± 8 cGy) agreed with the 3D-camera planned dose of 209 ± 6 cGy, compared to 192 ± 6 cGy for the flat-phantom calculation (same MUs). CONCLUSIONS: Electron beam dosimetry is affected by irregular body surfaces. 3D cameras can capture irregular body contours which allow accurate dosimetry of electron beam treatment as an alternative to costly CT scans with no extra exposure to radiation. Tools and workflow for clinical implementation are provided.


Assuntos
Elétrons , Tomografia Computadorizada por Raios X , Humanos , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
17.
Phys Med Biol ; 66(7)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33657537

RESUMO

Purpose. Radiation dose delivered to targets located near the upper-abdomen or in the thorax are significantly affected by respiratory-motion. Relatively large-margins are commonly added to compensate for this motion, limiting radiation-dose-escalation. Internal-surrogates of target motion, such as a radiofrequency (RF) tracking system, i.e. Calypso®System, are used to overcome this challenge and improve normal-tissue sparing. RF tracking systems consist of implanting transponders in the vicinity of the tumor to be tracked using radiofrequency-waves. Unfortunately, although the manufacture provides a universal quality-assurance (QA) phantom, QA-phantoms specifically for lung-applications are limited, warranting the development of alternative solutions to fulfil the tests mandated by AAPM's TG142. Accordingly, our objective was to design and develop a motion-phantom to evaluate Calypso for lung-applications that allows the Calypso®Beacons to move in different directions to better simulate truelung-motion.Methods and Materials.A Calypso lung QA-phantom was designed, and 3D-printed. The design consists of three independent arms where the transponders were attached. A pinpoint-chamber with a buildup-cap was also incorporated. A 4-axis robotic arm was programmed to drive the motion-phantom to mimic breathing. After acquiring a four-dimensional-computed-tomography (4DCT) scan of the motion-phantom, treatment-plans were generated and delivered on a Varian TrueBeam®with Calypso capabilities. Stationary and gated-treatment plans were generated and delivered to determine the dosimetric difference between gated and non-gated treatments. Portal cine-images were acquired to determine the temporal-accuracy of delivery by calculating the difference between the observed versus expected transponders locations with the known speed of the transponders' motion.Results.Dosimetric accuracy is better than the TG142 tolerance of 2%. Temporal accuracy is greater than, TG142 tolerance of 100 ms for beam-on, but less than 100 ms for beam-hold.Conclusions.The robotic QA-phantom designed and developed in this study provides an independent phantom for performing Calypso lung-QA for commissioning and acceptance testing of Calypso for lung treatments.


Assuntos
Procedimentos Cirúrgicos Robóticos , Humanos , Pulmão/diagnóstico por imagem , Neonicotinoides , Imagens de Fantasmas , Impressão Tridimensional , Tiazinas
18.
Cancer Cell ; 39(4): 509-528.e20, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33577785

RESUMO

Glioblastoma (GBM) is the most aggressive nervous system cancer. Understanding its molecular pathogenesis is crucial to improving diagnosis and treatment. Integrated analysis of genomic, proteomic, post-translational modification and metabolomic data on 99 treatment-naive GBMs provides insights to GBM biology. We identify key phosphorylation events (e.g., phosphorylated PTPN11 and PLCG1) as potential switches mediating oncogenic pathway activation, as well as potential targets for EGFR-, TP53-, and RB1-altered tumors. Immune subtypes with distinct immune cell types are discovered using bulk omics methodologies, validated by snRNA-seq, and correlated with specific expression and histone acetylation patterns. Histone H2B acetylation in classical-like and immune-low GBM is driven largely by BRDs, CREBBP, and EP300. Integrated metabolomic and proteomic data identify specific lipid distributions across subtypes and distinct global metabolic changes in IDH-mutated tumors. This work highlights biological relationships that could contribute to stratification of GBM patients for more effective treatment.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteogenômica , Neoplasias Encefálicas/patologia , Biologia Computacional/métodos , Glioblastoma/patologia , Humanos , Metabolômica/métodos , Mutação/genética , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Fosforilação/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteogenômica/métodos , Proteômica/métodos
19.
Med Phys ; 48(1): 366-375, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33107049

RESUMO

PURPOSE: The dosimetric properties of inverse Compton (IC) x-ray sources were investigated to determine their utility for stereotactic radiation therapy. METHODS: Monte Carlo simulations were performed using the egs brachy user code of EGSnrc. Nominal IC source x-ray energies of 80 and 150 keV were considered in this work. Depth-dose and lateral dose profiles in water were calculated, as was dose enhancement in the bone. Further simulations were performed for brain and spine treatment sites. The impact of gold nanoparticle doping was also investigated for the brain treatment site. Analogous dose calculations were performed in a clinical treatment planning system using a clinical 6 MV photon beam model and were compared to the Monte Carlo simulations. RESULTS: Both 80 and 150 keV IC beams were observed to have sharp 80-20 penumbra (i.e., < 0.1 mm) with broad low-dose tails in water. For reference, the calculated penumbra for the 6 MV clinical beam was 3 mm. Maximum dose enhancement factors in bone of 3.1, 1.4, and 1.1 were observed for the 80, 150 keV, and clinical 6 MV beams, respectively. The plan quality for the single brain metastasis case was similar between the IC beams and the 6 MV beam without gold nanoparticles. As the concentration of gold within the target increased, the V12 Gy to the normal brain tissue and D max within the target volume significantly decreased and the conformity significantly improved, which resulted in superior plan quality over the clinical 6 MV beam plan. In the spine cases, the sharp penumbra and enhanced dose to bone of the IC beams produced superior plan quality (i.e., better conformity, normal tissue sparing, and spinal cord sparing) as compared to the clinical 6 MV beam plans. CONCLUSIONS: The findings from this work indicate that inverse Compton x-ray sources are well suited for stereotactic radiotherapy treatments due to their sharp penumbra and dose enhancement around high atomic number materials. Future work includes investigating the properties of intensity-modulated inverse Compton x-ray sources to improve the homogeneity within the target tissue.


Assuntos
Nanopartículas Metálicas , Radiocirurgia , Ouro , Método de Monte Carlo , Radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Raios X
20.
Ultrasound Obstet Gynecol ; 57(3): 493-497, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32149430

RESUMO

To illustrate the prenatal cerebral imaging features associated with tubulinopathy, we report on five affected fetuses from unrelated families, with a de-novo heterozygous variant in a tubulin gene (TUBA1A, TUBB2B or TUBB3). We identified two distinct prenatal imaging patterns related to tubulinopathy: a severe form, characterized by enlarged germinal matrices, microlissencephaly and a kinked brainstem; and a mild form which has not been reported previously in the prenatal literature. The latter form is associated with non-specific features, including an asymmetric brainstem, corpus callosal dysgenesis, a lack of Sylvian fissure operculization and distortion of the anterior part of the interhemispheric fissure with subsequent impacted medial borders of the frontal lobes, the combination of which, in the absence of additional extracerebral anomalies, is highly suggestive of tubulinopathy. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/embriologia , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/embriologia , Ultrassonografia Pré-Natal , Tronco Encefálico/anormalidades , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/embriologia , Córtex Cerebral/anormalidades , Feminino , Feto/anormalidades , Feto/diagnóstico por imagem , Feto/embriologia , Variação Genética , Humanos , Malformações do Desenvolvimento Cortical/genética , Ilustração Médica , Microcefalia/diagnóstico por imagem , Microcefalia/embriologia , Gravidez , Tubulina (Proteína)/genética
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