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1.
Int J Pharm ; 650: 123664, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38061498

RESUMO

Nose-to-brain delivery presents an attractive administration route for neuroactive drugs that suffer from compromised bioavailability or fail to pass the blood-brain barrier. However, the conventional gauge of effectiveness for intranasal delivery platforms primarily involves detecting the presence of the administered drug within the brain, with little insight into its precise localization within brain structures. This may undermine the therapeutic efficacy of drugs and hinder the design of systems that target specific brain regions. In this study, we designed two intranasal delivery systems for the antipsychotic drug, olanzapine, and evaluated its distribution in the rat brain following intranasal administration. The first evaluated system was an olanzapine-loaded microemulsion and the second one was nanoparticulate aqueous dispersion of olanzapine. Both systems exhibited characteristics that render them compatible for intranasal administration, and successfully delivered olanzapine to the brain. We further employed an ambient mass spectrometry imaging method, called desorption electrospray ionization mass spectrometry imaging, to visualize the signal intensity of olanzapine in different brain regions following the intranasal administration of these two systems. Substantial variations in the distribution patterns of olanzapine across various brain structures were revealed, potentially highlighting the importance of mass spectrometry imaging in designing and evaluating intranasal drug delivery platforms.


Assuntos
Antipsicóticos , Espectrometria de Massas por Ionização por Electrospray , Ratos , Animais , Olanzapina , Antipsicóticos/química , Administração Intranasal , Encéfalo , Sistemas de Liberação de Medicamentos
2.
Eur Radiol ; 34(3): 1635-1644, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37656176

RESUMO

OBJECTIVES: Adipose tissue radiodensity in computed tomography (CT) performed before surgeries can predict surgical difficulty. Despite its clinical importance, little is known about what influences radiodensity. This study combines desorption electrospray ionization mass spectrometry imaging (DESI-MSI) and electrospray ionization (ESI) with machine learning to unveil how chemical composition of adipose tissue determines its radiodensity. METHODS: Patients in the study underwent abdominal surgeries. Before surgery, CT radiodensity of fat near operated sites was measured. Fifty-three fat samples were collected and analyzed by DESI-MSI, ESI, and histology, and then sorted by radiodensity, demographic parameters, and adipocyte size. A non-negative matrix factorization (NMF) algorithm was developed to differentiate between high and low radiodensities. RESULTS: No associations between radiodensity and patient age, gender, weight, height, or fat origin were found. Body mass index showed negative correlation with radiodensity. A substantial difference in chemical composition between adipose tissues of high and low radiodensities was observed. More radiodense tissues exhibited greater abundance of high molecular weight species, such as phospholipids of various types, ceramides, cholesterol esters and diglycerides, and about 70% smaller adipocyte size. Less radiodense tissue showed high abundance of short acyl-tail fatty acids. CONCLUSIONS: This study unveils the connection between abdominal adipose tissue radiodensity and its chemical composition. Because the radiodensity of the fat around the surgical site is associated with surgical difficulty, it is important to understand how adipose tissue composition affects this parameter. We conclude that fat tissue with a higher content of various phospholipids and waxy lipids is more CT radiodense. CLINICAL RELEVANCE STATEMENT: This study establishes the connection between the CT radiodensity of adipose tissue and its chemical composition. Clinicians may use this information for preoperative planning of surgical procedures, potentially modifying their surgical approach (for example, performing partial nephrectomy openly rather than laparoscopically). KEY POINTS: • Adipose tissue radiodensity values in computed tomography images taken prior to the surgery can potentially predict surgery difficulty. • Fifty-three human specimens were analyzed by advanced mass spectrometry, molecular imaging, and machine learning to establish the key features that determine Hounsfield units' values of adipose tissue. • The findings of this research will enable clinicians to better prepare for surgical procedures and select operative strategies.


Assuntos
Tecido Adiposo , Tomografia Computadorizada por Raios X , Humanos , Tecido Adiposo/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Sobrepeso
3.
Mass Spectrom Rev ; 42(2): 751-778, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34642958

RESUMO

Desorption electrospray ionization mass spectrometry imaging (DESI-MSI) is one of the least specimen destructive ambient ionization mass spectrometry tissue imaging methods. It enables rapid simultaneous mapping, measurement, and identification of hundreds of molecules from an unmodified tissue sample. Over the years, since its first introduction as an imaging technique in 2005, DESI-MSI has been extensively developed as a tool for separating tissue regions of various histopathologic classes for diagnostic applications. Recently, DESI-MSI has also emerged as a versatile technique that enables drug discovery and can guide the efficient development of drug delivery systems. For example, it has been increasingly employed for uncovering unique patterns of in vivo drug distribution, the discovery of potentially treatable biochemical pathways, revealing novel druggable targets, predicting therapeutic sensitivity of diseased tissues, and identifying early tissue response to pharmacological treatment. These and other recent advances in implementing DESI-MSI as the tool for the development of novel therapies are highlighted in this review.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Descoberta de Drogas , Sistemas de Liberação de Medicamentos , Diagnóstico por Imagem
4.
ACS Med Chem Lett ; 13(4): 615-622, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35450373

RESUMO

A natural compound screen identified several anticancer compounds, among which azapodophyllotoxin (AZP) was found to be the most potent. AZP caused decreased viability of both mouse and human lymphoma and renal cell cancer (RCC) tumor-derived cell lines. Novel AZP derivatives were synthesized and screened identifying compound NSC750212 to inhibit the growth of both lymphoma and RCC both in vitro and in vivo. A nanoimmunoassay was used to assess the NSC750212 mode of action in vivo. On the basis of the structure of AZP and its mode of action, AZP disrupts tubulin polymerization. Through desorption electrospray ionization mass spectrometry imaging, NSC750212 was found to inhibit lipid metabolism. NSC750212 suppresses monoglycerol metabolism depleting lipids and thereby inhibits tumor growth. The dual mode of tubulin polymerization disruption and monoglycerol metabolism inhibition makes NSC750212 a potent small molecule against lymphoma and RCC.

5.
Cell Rep ; 38(9): 110453, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35235785

RESUMO

Inherited pathogenic succinate dehydrogenase (SDHx) gene mutations cause the hereditary pheochromocytoma and paraganglioma tumor syndrome. Syndromic tumors exhibit elevated succinate, an oncometabolite that is proposed to drive tumorigenesis via DNA and histone hypermethylation, mitochondrial expansion, and pseudohypoxia-related gene expression. To interrogate this prevailing model, we disrupt mouse adrenal medulla SDHB expression, which recapitulates several key molecular features of human SDHx tumors, including succinate accumulation but not 5hmC loss, HIF accumulation, or tumorigenesis. By contrast, concomitant SDHB and the neurofibromin 1 tumor suppressor disruption yields SDHx-like pheochromocytomas. Unexpectedly, in vivo depletion of the 2-oxoglutarate (2-OG) dioxygenase cofactor ascorbate reduces SDHB-deficient cell survival, indicating that SDHx loss may be better tolerated by tissues with high antioxidant capacity. Contrary to the prevailing oncometabolite model, succinate accumulation and 2-OG-dependent dioxygenase inhibition are insufficient for mouse pheochromocytoma tumorigenesis, which requires additional growth-regulatory pathway activation.


Assuntos
Neoplasias das Glândulas Suprarrenais , Dioxigenases , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Animais , Carcinogênese/genética , Transformação Celular Neoplásica , Dioxigenases/metabolismo , Camundongos , Feocromocitoma/genética , Feocromocitoma/metabolismo , Feocromocitoma/patologia , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Succinatos , Ácido Succínico/metabolismo
6.
Front Oncol ; 11: 665763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968771

RESUMO

BACKGROUND: There is increasing evidence that adipocytes play an active role in the cancer microenvironment. We have previously reported that adipocytes interact with acute lymphoblastic leukemia (ALL) cells, contributing to chemotherapy resistance and treatment failure. In the present study, we investigated whether part of this resistance is due to adipocyte provision of lipids to ALL cells. METHODS: We cultured 3T3-L1 adipocytes, and tested whether ALL cells or ALL-released cytokines induced FFA release. We investigated whether ALL cells took up these FFA, and using fluorescent tagged BODIPY-FFA and lipidomics, evaluated which lipid moieties were being transferred from adipocytes to ALL. We evaluated the effects of adipocyte-derived lipids on ALL cell metabolism using a Seahorse XF analyzer and expression of enzymes important for lipid metabolism, and tested whether these lipids could protect ALL cells from chemotherapy. Finally, we evaluated a panel of lipid synthesis and metabolism inhibitors to determine which were affected by the presence of adipocytes. RESULTS: Adipocytes release free fatty acids (FFA) when in the presence of ALL cells. These FFA are taken up by the ALL cells and incorporated into triglycerides and phospholipids. Some of these lipids are stored in lipid droplets, which can be utilized in states of fuel deprivation. Adipocytes preferentially release monounsaturated FFA, and this can be attenuated by inhibiting the desaturating enzyme steroyl-CoA decarboxylase-1 (SCD1). Adipocyte-derived FFA can relieve ALL cell endogenous lipogenesis and reverse the cytotoxicity of pharmacological acetyl-CoA carboxylase (ACC) inhibition. Further, adipocytes alter ALL cell metabolism, shifting them from glucose to FFA oxidation. Interestingly, the unsaturated fatty acid, oleic acid, protects ALL cells from modest concentrations of chemotherapy, such as those that might be present in the ALL microenvironment. In addition, targeting lipid synthesis and metabolism can potentially reverse adipocyte protection of ALL cells. CONCLUSION: These findings uncover a previously unidentified interaction between ALL cells and adipocytes, leading to transfer of FFA for use as a metabolic fuel and macromolecule building block. This interaction may contribute to ALL resistance to chemotherapy, and could potentially be targeted to improve ALL treatment outcome.

7.
Int J Mol Sci ; 22(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33430158

RESUMO

(1) Background: Chiral nanoparticular systems have recently emerged as a compelling platform for investigating stereospecific behavior at the nanoscopic level. We describe chiroselective supramolecular interactions that occur between DNA oligonucleotides and chiral polyurea nanocapsules. (2) Methods: We employ interfacial polyaddition reactions between toluene 2,4-diisocyanate and lysine enantiomers that occur in volatile oil-in-water nanoemulsions to synthesize hollow, solvent-free capsules with average sizes of approximately 300 nm and neutral surface potential. (3) Results: The resultant nanocapsules exhibit chiroptical activity and interact differentially with single stranded DNA oligonucleotides despite the lack of surface charge and, thus, the absence of significant electrostatic interactions. Preferential binding of DNA on D-polyurea nanocapsules compared to their L-counterparts is demonstrated by a fourfold increase in capsule size, a 50% higher rise in the absolute value of negative zeta potential (ζ-potential), and a three times lower free DNA concentration after equilibration with the excess of DNA. (4) Conclusions: We infer that the chirality of the novel polymeric nanocapsules affects their supramolecular interactions with DNA, possibly through modification of the surface morphology. These interactions can be exploited when developing carriers for gene therapy and theranostics. The resultant constructs are expected to be highly biocompatible due to their neutral potential and biodegradability of polyurea shells.


Assuntos
DNA/química , Portadores de Fármacos/farmacologia , Nanocápsulas/química , Oligonucleotídeos/química , Aptâmeros de Nucleotídeos/química , DNA/antagonistas & inibidores , Portadores de Fármacos/química , Emulsões/química , Emulsões/farmacologia , Humanos , Oligonucleotídeos/genética , Tamanho da Partícula , Polímeros/química
8.
J Speech Lang Hear Res ; 63(9): 3019-3035, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32791019

RESUMO

Purpose Data mining algorithms using electronic health records (EHRs) are useful in large-scale population-wide studies to classify etiology and comorbidities (Casey et al., 2016). Here, we apply this approach to developmental language disorder (DLD), a prevalent communication disorder whose risk factors and epidemiology remain largely undiscovered. Method We first created a reliable system for manually identifying DLD in EHRs based on speech-language pathologist (SLP) diagnostic expertise. We then developed and validated an automated algorithmic procedure, called, Automated Phenotyping Tool for identifying DLD cases in health systems data (APT-DLD), that classifies a DLD status for patients within EHRs on the basis of ICD (International Statistical Classification of Diseases and Related Health Problems) codes. APT-DLD was validated in a discovery sample (N = 973) using expert SLP manual phenotype coding as a gold-standard comparison and then applied and further validated in a replication sample of N = 13,652 EHRs. Results In the discovery sample, the APT-DLD algorithm correctly classified 98% (concordance) of DLD cases in concordance with manually coded records in the training set, indicating that APT-DLD successfully mimics a comprehensive chart review. The output of APT-DLD was also validated in relation to independently conducted SLP clinician coding in a subset of records, with a positive predictive value of 95% of cases correctly classified as DLD. We also applied APT-DLD to the replication sample, where it achieved a positive predictive value of 90% in relation to SLP clinician classification of DLD. Conclusions APT-DLD is a reliable, valid, and scalable tool for identifying DLD cohorts in EHRs. This new method has promising public health implications for future large-scale epidemiological investigations of DLD and may inform EHR data mining algorithms for other communication disorders. Supplemental Material https://doi.org/10.23641/asha.12753578.


Assuntos
Registros Eletrônicos de Saúde , Transtornos do Desenvolvimento da Linguagem , Algoritmos , Mineração de Dados , Dimaprit/análogos & derivados , Humanos
9.
Nanoscale ; 12(4): 2752-2763, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31956862

RESUMO

Dysregulated myeloid cell activity underlies a variety of pathologies, including immunosuppression in malignant cancers. Current treatments to alter myeloid cell behavior also alter other immune cell subpopulations and nonimmune cell types with deleterious side effects. Therefore, improved selectivity of myeloid treatment is an urgent need. To meet this need, we demonstrate a novel, targeted nanoparticle system that achieves superior myeloid selectivity both in vitro and in vivo. This system comprises: (1) granulocyte-colony stimulating factor (G-CSF) as a targeting ligand to promote accumulation in myeloid cells, including immunosuppressive myeloid-derived suppressor cells (MDSCs); (2) albumin nanoparticles 100-120 nm in diameter that maintain morphology and drug payload in simulated physiological conditions; and (3) a fluorophore that enables nanoparticle tracking and models a therapeutic molecule. Here, we show that this strategy achieves high myeloid uptake in mixed primary immune cells and that nanoparticles successfully infiltrate the 4T1 triple-negative breast tumor murine microenvironment, where they preferentially accumulate in myeloid cells in a mouse model. Further development will realize diagnostic myeloid cell tracking applications and therapeutic delivery of myeloid-reprogramming drugs.


Assuntos
Albuminas/química , Sistemas de Liberação de Medicamentos , Fator Estimulador de Colônias de Granulócitos/metabolismo , Células Mieloides/metabolismo , Nanopartículas/química , Baço/efeitos dos fármacos , Animais , Bovinos , Linhagem Celular , Tolerância Imunológica , Terapia de Imunossupressão , Ligantes , Luz , Camundongos , Células Mieloides/imunologia , Células RAW 264.7 , Espalhamento de Radiação , Soroalbumina Bovina/química , Temperatura
10.
Cell Metab ; 30(3): 556-572.e5, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31447321

RESUMO

Lipid metabolism is frequently perturbed in cancers, but the underlying mechanism is unclear. We present comprehensive evidence that oncogene MYC, in collaboration with transcription factor sterol-regulated element-binding protein (SREBP1), regulates lipogenesis to promote tumorigenesis. We used human and mouse tumor-derived cell lines, tumor xenografts, and four conditional transgenic mouse models of MYC-induced tumors to show that MYC regulates lipogenesis genes, enzymes, and metabolites. We found that MYC induces SREBP1, and they collaborate to activate fatty acid (FA) synthesis and drive FA chain elongation from glucose and glutamine. Further, by employing desorption electrospray ionization mass spectrometry imaging (DESI-MSI), we observed in vivo lipidomic changes upon MYC induction across different cancers, for example, a global increase in glycerophosphoglycerols. After inhibition of FA synthesis, tumorigenesis was blocked, and tumors regressed in both xenograft and primary transgenic mouse models, revealing the vulnerability of MYC-induced tumors to the inhibition of lipogenesis.


Assuntos
Carcinogênese/genética , Lipogênese/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Linhagem Celular Tumoral , Ácidos Graxos/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-myc/genética
11.
Anal Chem ; 90(20): 12198-12206, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30188683

RESUMO

Lipid profile changes in heart muscle have been previously linked to cardiac ischemia and myocardial infarction, but the spatial distribution of lipids and metabolites in ischemic heart remains to be fully investigated. We performed desorption electrospray ionization mass spectrometry imaging of hearts from in vivo myocardial infarction mouse models. In these mice, myocardial ischemia was induced by blood supply restriction via a permanent ligation of left anterior descending coronary artery. We showed that applying the machine learning algorithm of gradient boosting tree ensemble to the ambient mass spectrometry imaging data allows us to distinguish segments of infarcted myocardium from normally perfused hearts on a pixel by pixel basis. The machine learning algorithm selected 62 molecular ion peaks important for classification of each 200 µm-diameter pixel of the cardiac tissue map as normally perfused or ischemic. This approach achieved very high average accuracy (97.4%), recall (95.8%), and precision (96.8%) at a spatial resolution of ∼200 µm. In addition, we determined the chemical identity of 27 species, mostly small metabolites and lipids, selected by the algorithm as the most significant for cardiac pathology classification. This molecular signature of myocardial infarction may provide new mechanistic insights into cardiac ischemia, assist with infarct size assessment, and point toward novel therapeutic interventions.


Assuntos
Ácidos Graxos Insaturados/análise , Aprendizado de Máquina , Imagem Molecular , Infarto do Miocárdio/diagnóstico por imagem , Animais , Feminino , Camundongos , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
12.
Proc Natl Acad Sci U S A ; 115(25): 6347-6352, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29866838

RESUMO

Detection of microscopic skin lesions presents a considerable challenge in diagnosing early-stage malignancies as well as in residual tumor interrogation after surgical intervention. In this study, we established the capability of desorption electrospray ionization mass spectrometry imaging (DESI-MSI) to distinguish between micrometer-sized tumor aggregates of basal cell carcinoma (BCC), a common skin cancer, and normal human skin. We analyzed 86 human specimens collected during Mohs micrographic surgery for BCC to cross-examine spatial distributions of numerous lipids and metabolites in BCC aggregates versus adjacent skin. Statistical analysis using the least absolute shrinkage and selection operation (Lasso) was employed to categorize each 200-µm-diameter picture element (pixel) of investigated skin tissue map as BCC or normal. Lasso identified 24 molecular ion signals, which are significant for pixel classification. These ion signals included lipids observed at m/z 200-1,200 and Krebs cycle metabolites observed at m/z < 200. Based on these features, Lasso yielded an overall 94.1% diagnostic accuracy pixel by pixel of the skin map compared with histopathological evaluation. We suggest that DESI-MSI/Lasso analysis can be employed as a complementary technique for delineation of microscopic skin tumors.


Assuntos
Carcinoma Basocelular/diagnóstico , Imagem Molecular/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Biomarcadores Tumorais , Humanos , Lipídeos/química , Cirurgia de Mohs/métodos , Neoplasias , Agregados Proteicos/fisiologia , Neoplasias Cutâneas/diagnóstico
13.
J Exp Child Psychol ; 170: 86-106, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29453130

RESUMO

Developmental research beginning in the 1970s has suggested that children's ability to form cognitive maps reaches adult levels during early adolescence. However, this research has used a variety of testing procedures, often in real-world environments, which have been difficult to share widely across labs and to use to probe components of mapping, individual differences in success, and possible mechanisms of development and reasons for individual variation. In this study, we charted the development of cognitive mapping using a virtual navigation paradigm, Silcton, that allows for testing samples of substantial size in a uniform way and in which adults show marked individual differences in the formation of accurate route representations and/or in route integration. The current study tested children aged between 8 and 16 years. In terms of components of normative development, children's performance reached adult levels of proficiency at around age 12, but route representation progressed significantly more quickly than route integration. In terms of individual differences, by age 12 children could be grouped into the same three categories evident in adults: imprecise navigators (who form only imprecise ideas of routes), non-integrators (who represent routes more accurately but are imprecise in relating two routes), and integrators (who relate the two routes and, thus, form cognitive maps). Thus, individual differences likely originate during childhood. In terms of correlates, perspective-taking skills predicted navigation performance better than mental rotation skills, in accord with the view that perspective taking operates on extrinsic spatial representations, whereas mental rotation taps intrinsic spatial representations.


Assuntos
Cognição/fisiologia , Navegação Espacial/fisiologia , Adolescente , Adulto , Criança , Desenvolvimento Infantil/fisiologia , Feminino , Humanos , Individualidade , Masculino , Rotação , Caracteres Sexuais
14.
Angew Chem Int Ed Engl ; 56(51): 16357-16362, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29080292

RESUMO

Template-free fabrication of non-spherical polymeric nanoparticles is desirable for various applications, but has had limited success owing to thermodynamic favorability of sphere formation. Herein we present a simple way to prepare cubic nanoparticles of block copolymers by self-assembly from aqueous solutions at room temperature. Nanocubes with edges of 40-200 nm are formed spontaneously on different surfaces upon water evaporation from micellar solutions of triblock copolymers containing a central poly(ethylene oxide) block and terminal trimethylene carbonate/dithiolane blocks. These polymers self-assemble into 28±5 nm micelles in water. Upon drying, micelle aggregation and a kinetically controlled crystallization of central blocks evidently induce solid cubic particle formation. An approach for preserving the structures of these cubes in water by thiol- or photo-induced crosslinking was developed. The ability to solubilize a model hydrophobic drug, curcumin, was also explored.

15.
Proc Natl Acad Sci U S A ; 114(17): 4300-4305, 2017 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-28400509

RESUMO

KRAS gene mutation causes lung adenocarcinoma. KRAS activation has been associated with altered glucose and glutamine metabolism. Here, we show that KRAS activates lipogenesis, and this activation results in distinct proteomic and lipid signatures. By gene expression analysis, KRAS is shown to be associated with a lipogenesis gene signature and specific induction of fatty acid synthase (FASN). Through desorption electrospray ionization MS imaging (DESI-MSI), specific changes in lipogenesis and specific lipids are identified. By the nanoimmunoassay (NIA), KRAS is found to activate the protein ERK2, whereas ERK1 activation is found in non-KRAS-associated human lung tumors. The inhibition of FASN by cerulenin, a small molecule antibiotic, blocked cellular proliferation of KRAS-associated lung cancer cells. Hence, KRAS is associated with activation of ERK2, induction of FASN, and promotion of lipogenesis. FASN may be a unique target for KRAS-associated lung adenocarcinoma remediation.


Assuntos
Adenocarcinoma/enzimologia , Ácido Graxo Sintases/metabolismo , Lipogênese , Neoplasias Pulmonares/enzimologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Ácido Graxo Sintases/genética , Humanos , Metabolismo dos Lipídeos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais
16.
PLoS Med ; 13(8): e1002108, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27575375

RESUMO

BACKGROUND: Surgical resection with microscopically negative margins remains the main curative option for pancreatic cancer; however, in practice intraoperative delineation of resection margins is challenging. Ambient mass spectrometry imaging has emerged as a powerful technique for chemical imaging and real-time diagnosis of tissue samples. We applied an approach combining desorption electrospray ionization mass spectrometry imaging (DESI-MSI) with the least absolute shrinkage and selection operator (Lasso) statistical method to diagnose pancreatic tissue sections and prospectively evaluate surgical resection margins from pancreatic cancer surgery. METHODS AND FINDINGS: Our methodology was developed and tested using 63 banked pancreatic cancer samples and 65 samples (tumor and specimen margins) collected prospectively during 32 pancreatectomies from February 27, 2013, to January 16, 2015. In total, mass spectra for 254,235 individual pixels were evaluated. When cross-validation was employed in the training set of samples, 98.1% agreement with histopathology was obtained. Using an independent set of samples, 98.6% agreement was achieved. We used a statistical approach to evaluate 177,727 mass spectra from samples with complex, mixed histology, achieving an agreement of 81%. The developed method showed agreement with frozen section evaluation of specimen margins in 24 of 32 surgical cases prospectively evaluated. In the remaining eight patients, margins were found to be positive by DESI-MSI/Lasso, but negative by frozen section analysis. The median overall survival after resection was only 10 mo for these eight patients as opposed to 26 mo for patients with negative margins by both techniques. This observation suggests that our method (as opposed to the standard method to date) was able to detect tumor involvement at the margin in patients who developed early recurrence. Nonetheless, a larger cohort of samples is needed to validate the findings described in this study. Careful evaluation of the long-term benefits to patients of the use of DESI-MSI for surgical margin evaluation is also needed to determine its value in clinical practice. CONCLUSIONS: Our findings provide evidence that the molecular information obtained by DESI-MSI/Lasso from pancreatic tissue samples has the potential to transform the evaluation of surgical specimens. With further development, we believe the described methodology could be routinely used for intraoperative surgical margin assessment of pancreatic cancer.


Assuntos
Margens de Excisão , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Humanos , Imagem Molecular , Pâncreas/patologia , Pâncreas/cirurgia , Pancreatectomia/métodos , Neoplasias Pancreáticas/patologia , Estudos Prospectivos , Espectrometria de Massas por Ionização por Electrospray
17.
Bull Environ Contam Toxicol ; 95(6): 734-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26408032

RESUMO

Permethrin, a poorly water-soluble synthetic pesticide belonging to the pyrethroid family, was formulated into water-dispersive nanometric form by rapid evaporation of pesticide loaded oil-in-water microemulsion. The mean hydrodynamic diameter of Nanopermethrin was found to be 199.01 ± 1.4 nm. The efficacy of the Nanopermethrin was comparatively investigated with its bulk form against 2-3 days old adult mosquitoes by WHO cone bioassay for 60 min. The median knockdown concentration of Culex tritaeniorhynchus, Culex quinquefasciatus and Aedes albopictus were found to be 7.20 × 10(4), 7.53 × 10(4), 0.42 × 10(3) mg/L for Bulk permethrin, and 0.98 × 10(4), 1.17 × 10(4), 0.05 × 10(3) mg/L for Nanopermethrin, respectively. The obtained results extrapolate the improved efficacy of Nanopermethrin even at low-level concentrations. Hence, the formulated Nanopermethrin will serve as an effective alternative pesticide in controlling the mosquito population with reduced environmental toxicity.


Assuntos
Aedes , Culex , Inseticidas , Nanoestruturas , Permetrina , Animais , Poluição Ambiental/prevenção & controle , Água
18.
ACS Nano ; 9(9): 9416-26, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26244654

RESUMO

Controllable induction of blood vessel formation (angiogenesis) presents an important therapeutic goal in ischemic diseases and is also beneficial in various normal physiological processes. In this study, we have shown that nanoparticles of celecoxib, a lipophilic nonsteroidal anti-inflammatory drug, effectively evoke therapeutic angiogenesis in animal models, in both normal and ischemic organs. Celecoxib is widely considered to inhibit angiogenesis, although a recent study suggests that it can instead promote blood vessel growth in cancer cell lines. The hydrophobic nature of this drug necessitates its administration in nanoparticulate form in order to elicit a perceivable pharmacological response. We developed a facile method for nanoparticle formation by solvent extraction from microemulsions in supercritical carbon dioxide. This method exploits a spontaneous formation of nanometric domains within the microemulsion system and their rapid conversion to nanoparticles by supercritical fluid. The resultant nanoparticles were administered subcutaneously to mice in a biocompatible hydrogel, and caused a 4-fold increase in blood vessel count in normally perfused skin compared with drug-free particles. They were at least as effective in inducing angiogenesis as nanoparticles of deferoxamine, a well-established neovascularization promoter. Next, we evaluated their effect on ischemic tissues in murine model of myocardial infarction. We found that celecoxib nanoparticles were able to induce a significant vascularization of ischemic myocardium and hamper the progression of heart failure, which points toward a new approach for treating ischemia.


Assuntos
Celecoxib/administração & dosagem , Isquemia/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Nanopartículas/administração & dosagem , Neovascularização Fisiológica/efeitos dos fármacos , Indutores da Angiogênese/administração & dosagem , Indutores da Angiogênese/química , Animais , Vasos Sanguíneos/efeitos dos fármacos , Celecoxib/química , Modelos Animais de Doenças , Humanos , Isquemia/patologia , Camundongos , Infarto do Miocárdio/patologia , Nanopartículas/química
19.
J Colloid Interface Sci ; 434: 65-70, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25168584

RESUMO

Nanometric particles of a model hydrophobic substance curcumin were prepared by a novel method, namely, flash nanoprecipitation from a coarse oil-in-water emulsion. The method employs turbulent co-mixing of water with curcumin-loaded emulsion using manually-operated confined impingement jets mixer. A clear and stable dispersion of nanoparticles was formed in this process, and could be converted to dry, easily water-dispersible powder by spray drying. The mean size of the particles was about 40 nm by DLS, confirmed by Cryo-TEM. The obtained particles contained 20.4 wt% curcumin, X-ray analysis showed it was amorphous. The significant advantages of the studied process are its feasibility, speed and low cost. It does not require any special high-energy input equipment to reduce the droplet size of the initial emulsion as required by the vast majority of other methods, and relies on rapid turbulent mixing and on flow-induced shear stress formed in the simple, manually-operated mixer. Control experiments clearly indicate that employing emulsion, instead of a plain solution and flash nanoprecipitation instead of a simple antisolvent precipitation are advantageous in terms of particle size and stability.


Assuntos
Antineoplásicos/administração & dosagem , Curcumina/administração & dosagem , Emulsões/química , Nanopartículas/química , Antineoplásicos/química , Precipitação Química , Curcumina/química , Dessecação , Composição de Medicamentos/instrumentação , Desenho de Equipamento , Tamanho da Partícula , Pós , Solubilidade , Água/química
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