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1.
Immunity ; 42(3): 419-30, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25786174

RESUMEN

Macrophage polarization involves a coordinated metabolic and transcriptional rewiring that is only partially understood. By using an integrated high-throughput transcriptional-metabolic profiling and analysis pipeline, we characterized systemic changes during murine macrophage M1 and M2 polarization. M2 polarization was found to activate glutamine catabolism and UDP-GlcNAc-associated modules. Correspondingly, glutamine deprivation or inhibition of N-glycosylation decreased M2 polarization and production of chemokine CCL22. In M1 macrophages, we identified a metabolic break at Idh, the enzyme that converts isocitrate to alpha-ketoglutarate, providing mechanistic explanation for TCA cycle fragmentation. (13)C-tracer studies suggested the presence of an active variant of the aspartate-arginosuccinate shunt that compensated for this break. Consistently, inhibition of aspartate-aminotransferase, a key enzyme of the shunt, inhibited nitric oxide and interleukin-6 production in M1 macrophages, while promoting mitochondrial respiration. This systems approach provides a highly integrated picture of the physiological modules supporting macrophage polarization, identifying potential pharmacologic control points for both macrophage phenotypes.


Asunto(s)
Redes Reguladoras de Genes/inmunología , Inmunidad Innata , Macrófagos/metabolismo , Mitocondrias/metabolismo , Transcripción Genética/inmunología , Animales , Ácido Argininosuccínico/inmunología , Ácido Argininosuccínico/metabolismo , Aspartato Aminotransferasa Mitocondrial/genética , Aspartato Aminotransferasa Mitocondrial/inmunología , Ácido Aspártico/inmunología , Ácido Aspártico/metabolismo , Quimiocina CCL22/genética , Quimiocina CCL22/inmunología , Ciclo del Ácido Cítrico , Regulación de la Expresión Génica , Glutamina/deficiencia , Glicosilación , Interleucina-6/genética , Interleucina-6/inmunología , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/inmunología , Macrófagos/clasificación , Macrófagos/citología , Macrófagos/inmunología , Redes y Vías Metabólicas/genética , Redes y Vías Metabólicas/inmunología , Ratones , Mitocondrias/genética , Mitocondrias/inmunología , Óxido Nítrico/inmunología , Óxido Nítrico/metabolismo , Transducción de Señal , Uridina Difosfato N-Acetilglucosamina/inmunología , Uridina Difosfato N-Acetilglucosamina/metabolismo
2.
Eur Radiol ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625612

RESUMEN

OBJECTIVE: To compare the diagnostic performance of [68Ga]DOTATATE PET/CT, [18F]FDG PET/CT, MRI of the spine, and whole-body CT and MRI for the detection of pheochromocytoma/paraganglioma (PPGL)-related spinal bone metastases. MATERIALS AND METHODS: Between 2014 and 2020, PPGL participants with spinal bone metastases prospectively underwent [68Ga]DOTATATE PET/CT, [18F]FDG PET/CT, MRI of the cervical-thoracolumbar spine (MRIspine), contrast-enhanced MRI of the neck and thoraco-abdominopelvic regions (MRIWB), and contrast-enhanced CT of the neck and thoraco-abdominopelvic regions (CTWB). Per-patient and per-lesion detection rates were calculated. Counting of spinal bone metastases was limited to a maximum of one lesion per vertebrae. A composite of all functional and anatomic imaging served as an imaging comparator. The McNemar test compared detection rates between the scans. Two-sided p values were reported. RESULTS: Forty-three consecutive participants (mean age, 41.7 ± 15.7 years; females, 22) with MRIspine were included who also underwent [68Ga]DOTATATE PET/CT (n = 43), [18F]FDG PET/CT (n = 43), MRIWB (n = 24), and CTWB (n = 33). Forty-one of 43 participants were positive for spinal bone metastases, with 382 lesions on the imaging comparator. [68Ga]DOTATATE PET/CT demonstrated a per-lesion detection rate of 377/382 (98.7%) which was superior compared to [18F]FDG (72.0%, 275/382, p < 0.001), MRIspine (80.6%, 308/382, p < 0.001), MRIWB (55.3%, 136/246, p < 0.001), and CTWB (44.8%, 132/295, p < 0.001). The per-patient detection rate of [68Ga]DOTATATE PET/CT was 41/41 (100%) which was higher compared to [18F]FDG PET/CT (90.2%, 37/41, p = 0.13), MRIspine (97.6%, 40/41, p = 1.00), MRIWB (95.7%, 22/23, p = 1.00), and CTWB (81.8%, 27/33, p = 0.03). CONCLUSIONS: [68Ga]DOTATATE PET/CT should be the modality of choice in PPGL-related spinal bone metastases due to its superior detection rate. CLINICAL RELEVANCE STATEMENT: In a prospective study of 43 pheochromocytoma/paraganglioma participants with spinal bone metastases, [68Ga]DOTATATE PET/CT had a superior per-lesion detection rate of 98.7% (377/382), compared to [18F]FDG PET/CT (p < 0.001), MRI of the spine (p < 0.001), whole-body CT (p < 0.001), and whole-body MRI (p < 0.001). KEY POINTS: • Data regarding head-to-head comparison between functional and anatomic imaging modalities to detect spinal bone metastases in pheochromocytoma/paraganglioma are limited. • [68Ga]DOTATATE PET/CT had a superior per-lesion detection rate of 98.7% in the detection of spinal bone metastases associated with pheochromocytoma/paraganglioma compared to other imaging modalities: [18]F-FDG PET/CT, MRI of the spine, whole-body CT, and whole-body MRI. • [68Ga]DOTATATE PET/CT should be the modality of choice in the evaluation of spinal bone metastases associated with pheochromocytoma/paraganglioma.

3.
Artículo en Inglés | MEDLINE | ID: mdl-37515400

RESUMEN

Paediatric phaeochromocytomas and paragangliomas (PPGLs), though rare tumours, are associated with significant disability and death in the most vulnerable of patients early in their lives. However, unlike cryptogenic and insidious disease states, the clinical presentation of paediatric patients with PPGLs can be rather overt, allowing early diagnosis, granted that salient findings are recognized. Additionally, with prompt and effective intervention, prognosis is favourable if timely intervention is implemented. For this reason, this review focuses on four exemplary paediatric cases, succinctly emphasizing the now state-of-the-art concepts in paediatric PPGL management.

4.
AAPS PharmSciTech ; 24(8): 219, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891363

RESUMEN

In the current work, screening of polymers viz. polyacrylic acid (PAA), polyvinyl pyrrolidone vinyl acetate (PVP VA), and hydroxypropyl methyl cellulose acetate succinate (HPMC AS) based on drug-polymer interaction and wetting property was done for the production of a stable amorphous solid dispersion (ASD) of a poorly water-soluble drug Riluzole (RLZ). PAA showed maximum interaction and wetting property hence, was selected for further studies. Solid state characterization studies confirmed the formation of ASD with PAA. Saturation solubility, dissolution profile, and in vivo pharmacokinetic data of the ASD formulation were generated in rats against its marketed tablet Rilutor. The RLZ:PAA ASD showed exponential enhancement in the dissolution of RLZ. Predicted and observed pharmacokinetic data in rats showed enhanced area under curve (AUC) and Cmax in plasma and brain with respect to Rilutor. Furthermore, a physiologically based pharmacokinetic (PBPK) model of rats for Rilutor and RLZ ASD was developed and then extrapolated to humans where physiological parameters were changed along with a biochemical parameter. The partition coefficient was kept similar in both species. The model was used to predict different exposure scenarios, and the simulated data was compared with observed data points. The PBPK model simulated Cmax and AUC was within two times the experimental data for plasma and brain. The Cmax and AUC in the brain increased with ASD compared to Rilutor for humans showing its potential in improving its biopharmaceutical performance and hence enhanced therapeutic efficacy. The model can predict the RLZ concentration in multiple compartments including plasma and liver.


Asunto(s)
Polímeros , Riluzol , Ratas , Humanos , Animales , Polímeros/química , Povidona/química , Solubilidad , Humectabilidad
5.
AJR Am J Roentgenol ; 218(2): 342-350, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34431366

RESUMEN

BACKGROUND. Recent professional society guidelines for radionuclide imaging of sporadic pheochromocytoma (PHEO) recommend 18F-fluorodihydroxyphenylala-nine (18F-FDOPA) as the radiotracer of choice, deeming 68Ga-DOTATATE and FDG to be second- and third-line agents, respectively. An additional agent, 18F-fluorodopamine (18F-FDA), remains experimental for PHEO detection. A paucity of research has performed head-to-head comparison among these agents. OBJECTIVE. The purpose of this study was to perform an intraindividual comparison of 68Ga-DOTATATE PET/CT, FDG PET/CT, 18F-FDOPA PET/CT, 18F-FDA PET/CT, CT, and MRI in visualization of sporadic primary PHEO. METHODS. This prospective study enrolled patients referred with clinical suspicion for sporadic PHEO. Patients were scheduled for 68Ga-DOTATATE PET/CT, FDG PET/CT, 18F-FDOPA PET/CT, 18F-FDA PET/CT, whole-body staging CT (portal venous phase), and MRI within a 3-month period. PET/CT examinations were reviewed by two nuclear medicine physicians, and CT and MRI were reviewed by two radiologists; differences were resolved by consensus. Readers scored lesions in terms of confidence in diagnosis of PHEO (1-5 scale; 4-5 considered positive for PHEO). Lesion-to-liver SUVmax was computed using both readers' measurements. Interreader agreement was assessed using intraclass correlation coefficients (ICCs) for SUVmax. Analysis included only patients with histologically confirmed PHEO on resection. RESULTS. The analysis included 14 patients (eight women, six men; mean age, 52.4 ± 16.8 [SD] years) with PHEO. Both 68Ga-DOTATATE PET/CT and FDG PET/CT were completed in all 14 patients, 18F-FDOPA PET/CT in 11, 18F-FDA PET/CT in 7, CT in 12, and MRI in 12. Mean conspicuity score for PHEO was 5.0 ± 0.0 for 18F-FDOPA PET/CT, 4.7 ± 0.5 for MRI, 4.6 ± 0.8 for 18F-FDA PET/CT, 4.4 ± 1.0 for 68Ga-DOTATATE PET/CT, 4.3 ± 1.0 for CT, and 4.1 ± 1.5 for FDG PET/CT. The positivity rate for PHEO was 100.0% (11/11) for 18F-FDOPA PET/CT, 100.0% (12/12) for MRI, 85.7% (6/7) for 18F-FDA PET/CT, 78.6% (11/14) for FDG PET/CT, 78.6% (11/14) for 68Ga-DOTATATE PET/CT, and 66.7% (8/12) for CT. Lesion-to-liver SUVmax was 10.5 for 18F-FDOPA versus 3.0-4.2 for the other tracers. Interreader agreement across modalities ranged from 85.7% to 100.0% for lesion positivity with ICCs of 0.55-1.00 for SUVmax measurements. CONCLUSION. Findings from this small intraindividual comparative study support 18F-FDOPA PET/CT as a preferred first-line imaging modality in evaluation of sporadic PHEO. CLINICAL IMPACT. This study provides data supporting current guidelines for imaging evaluation of suspected PHEO. TRIAL REGISTRATION. ClinicalTrials.gov NCT00004847.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Radioisótopos de Galio , Imagen por Resonancia Magnética/métodos , Feocromocitoma/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos , Glándulas Suprarrenales/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Octreótido/análogos & derivados , Compuestos Organometálicos , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X/métodos
6.
Mol Biol Rep ; 49(12): 12091-12107, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35752697

RESUMEN

Conventional agricultural practices rely heavily on chemical fertilizers to boost production. Among the fertilizers, phosphatic fertilizers are copiously used to ameliorate low-phosphate availability in the soil. However, phosphorus-use efficiency (PUE) for major cereals, including maize, is less than 30%; resulting in more than half of the applied phosphate being lost to the environment. Rock phosphate reserves are finite and predicted to exhaust in near future with the current rate of consumption. Thus, the dependence of modern agriculture on phosphatic fertilizers poses major food security and sustainability challenges. Strategies to optimize and improve PUE, like genetic interventions to develop high PUE cultivars, could have a major impact in this area. Here, we present the current understanding and recent advances in the biological phenomenon of phosphate uptake, translocation, and adaptive responses of plants under phosphate deficiency, with special reference to maize. Maize is one of the most important cereal crops that is cultivated globally under diverse agro-climatic conditions. It is an industrial, feed and food crop with multifarious uses and a fast-rising global demand and consumption. The interesting aspects of diversity in the root system architecture traits, the interplay between signaling pathways contributing to PUE, and an in-depth discussion on promising candidate genes for improving PUE in maize are elaborated.


Asunto(s)
Fósforo , Zea mays , Fósforo/metabolismo , Zea mays/genética , Zea mays/metabolismo , Fertilizantes , Productos Agrícolas/genética , Agricultura/métodos , Suelo/química , Fosfatos
7.
Bioorg Chem ; 106: 104501, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33280832

RESUMEN

Lung cancer is one of the most prevailed cancer worldwide. Many genes get mutated in lung cancer but the involvement of EGFR, KRAS, PTEN and PIK3CA are more common. Unavailability of potent drugs and resistance to the available drugs are major concern in the treatment of lung cancer. In the present research, mTOR was selected as an important alternative target for the treatment of lung cancer which involves the PI3K/AKT/mTOR pathway. We studied binding interactions of AZD-2014 with the mTOR protein to identify important interactions required to design potent mTOR inhibitors which was supported by QSAR studies. Pharmacophore based virtual screening studies provided core scaffold, THQ. Based on molecular docking interactions, 31 THQ derivatives were synthesized and characterized. All compounds were screened for cellular mTOR enzyme assay along with antiproliferative activity against the panel of cancerous cell lines, from which 6 compounds were further screened for colony forming assay. Two most potent compounds, HB-UC-1 and HB-UC-5, were further screened for flow cytometry analysis, gene expression study and western blot analysis. Gene expression study revealed the efficiency of compound HB-UC-1 against both mTORC1 and mTORC2 by affecting downstream regulators of mTORC1 (E4BP4, eIF4EBP1) and mTORC2 (PCK1), respectively. In western blot analysis, both compounds, inhibited phosphorylation of AKT S473 which proved the efficiency these compounds against the mTORC2. These two compounds were further screened for in-vivo biological evaluation. Both compounds increased lifespan of cancer-bearing animals with improvement in mean survival time. Further, in bezopyrene induced lung cancer animal model, both compounds showed effectiveness through the biochemical parameters and histopathological evaluation of the lung tissue. In future, potent hit compound from this series could be modified to develop lead mTOR inhibitors for the treatment of lung cancer.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 2 de la Rapamicina/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Quinolinas/farmacología , Células A549 , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Quinolinas/síntesis química , Quinolinas/química , Relación Estructura-Actividad
8.
Planta ; 251(4): 91, 2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32236850

RESUMEN

MAIN CONCLUSION: While transgenic technology has heralded a new era in crop improvement, several concerns have precluded their widespread acceptance. Alternative technologies, such as cisgenesis and genome-editing may address many of such issues and facilitate the development of genetically engineered crop varieties with multiple favourable traits. Genetic engineering and plant transformation have played a pivotal role in crop improvement via introducing beneficial foreign gene(s) or silencing the expression of endogenous gene(s) in crop plants. Genetically modified crops possess one or more useful traits, such as, herbicide tolerance, insect resistance, abiotic stress tolerance, disease resistance, and nutritional improvement. To date, nearly 525 different transgenic events in 32 crops have been approved for cultivation in different parts of the world. The adoption of transgenic technology has been shown to increase crop yields, reduce pesticide and insecticide use, reduce CO2 emissions, and decrease the cost of crop production. However, widespread adoption of transgenic crops carrying foreign genes faces roadblocks due to concerns of potential toxicity and allergenicity to human beings, potential environmental risks, such as chances of gene flow, adverse effects on non-target organisms, evolution of resistance in weeds and insects etc. These concerns have prompted the adoption of alternative technologies like cisgenesis, intragenesis, and most recently, genome editing. Some of these alternative technologies can be utilized to develop crop plants that are free from any foreign gene hence, it is expected that such crops might achieve higher consumer acceptance as compared to the transgenic crops and would get faster regulatory approvals. In this review, we present a comprehensive update on the current status of the genetically modified (GM) crops under cultivation. We also discuss the issues affecting widespread adoption of transgenic GM crops and comment upon the recent tools and techniques developed to address some of these concerns.


Asunto(s)
Productos Agrícolas/genética , Plantas Modificadas Genéticamente/genética , Animales , Resistencia a la Enfermedad/genética , Edición Génica , Flujo Génico , Ingeniería Genética/métodos , Resistencia a los Herbicidas/genética , Insectos , Nutrientes , Malezas , Estrés Fisiológico/genética
9.
Curr Treat Options Oncol ; 21(11): 85, 2020 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-32862332

RESUMEN

OPINION STATEMENT: The incidence of metastatic pheochromocytoma (PHEO) and paraganglioma (PGL) may occur in as many as 35% of patients particularly with PGL and even more frequently in those with specific mutations. Biochemical, morphological, and molecular markers have been investigated for use in the distinction of benign from malignant PHEO/PGL. PHEO/PGL metastasizes via hematogenous or lymphatic routes and shows differences based on mutational status. The most common sites of involvement in patients that have an SDHB mutation are the bone (78%), lungs (45%), lymph nodes (36%), and liver (35%). In patients with sporadic PHEO/PGL, the most common sites of metastasis are the bones (64%), lungs (47%), lymph nodes (36%), and liver (32%). Metastases may be present at presentation or may occur later. Metastases to the liver and lungs are associated with a shorter survival. Overall, the estimated 5-year survival rates are between 34 and 74%. Currently, treatments for metastatic PHEO/PGL are essentially palliative. Surgery is potentially curative; however, tumor dissemination limits the chance for a curative resection. When surgical intervention is not amenable, the therapeutic options include radiolabeled MIBG (Azedra®-iobenguane 131 was recently FDA-approved for patients > 12 years and older with iobenguane scan positive) or systemic chemotherapy with cyclophosphamide, vincristine, and dacarbazine (CVD) with an overall objective response rate (ORR) of less than 40%; however, it is not clear if the administration of CVD impacts overall survival, as nearly all patients develop progressive and ultimately fatal disease. Other treatment modalities under investigation include cytoreductive techniques, novel radiopharmaceuticals, chemotherapy, radiotherapy, immunotherapy, and experimental therapies. Here we are discussing emerging treatment for advanced/metastatic PHEO/PGL.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/terapia , Antineoplásicos/uso terapéutico , Paraganglioma/terapia , Feocromocitoma/terapia , Radiofármacos/uso terapéutico , 3-Yodobencilguanidina/uso terapéutico , Neoplasias de las Glándulas Suprarrenales/patología , Inhibidores de la Angiogénesis/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/secundario , Neoplasias Óseas/terapia , Ciclofosfamida/uso terapéutico , Procedimientos Quirúrgicos de Citorreducción , Dacarbazina/uso terapéutico , Everolimus/uso terapéutico , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Octreótido/análogos & derivados , Octreótido/uso terapéutico , Paraganglioma/patología , Paraganglioma/secundario , Feocromocitoma/patología , Feocromocitoma/secundario , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Procedimientos Quirúrgicos Operativos , Vincristina/uso terapéutico
10.
AAPS PharmSciTech ; 21(6): 207, 2020 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-32720079

RESUMEN

As the authors were working on similar projects on liposomes at the same time, the 3D figures of Fig. 3 bi and Fig. 3 bii were inadvertently misplaced.

11.
AAPS PharmSciTech ; 21(5): 151, 2020 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-32440910

RESUMEN

Triple-negative breast (TNBC) cancer that is upregulated with epidermal growth factor receptor (EGFR), and devoid of both the hormonal receptors and epidermal growth factor receptor 2 (HER 2), has led to a concept of treating TNBC with EGFR-targeted therapeutics. The combination of paclitaxel (PTX) and piperine (PIP) may improve the bioavailability of paclitaxel for cancer therapy. TPGS (vit E-PEG 1000-succinate)-coated liposomes were prepared with PTX alone or in combination with PIP, and either with (targeted) or without (non-targeted) cetuximab (CTX) conjugation. The Bradford assay indicated that 75% of CTX has been conjugated on the liposomes. The size and percent encapsulation of PTX&PIP co-loaded liposomes were found to be in the range of 204 to 218 nm and 31-73%, respectively. The drug release rate was found to be higher at pH 5.5 in comparison with release at pH 6.4 and pH 7.4. Cellular uptake and toxicity studies on MDA-MB-231 cells showed that PTX&PIP co-loaded targeted liposomes have demonstrated superior uptake and cytotoxicity than their non-targeted counterparts. The IC50 values of both of the liposomal formulations were found to be significantly higher than PTX control. Indeed, combining PIP with PTX control has improved the cytotoxicity of PTX control, which proved the synergistic anticancer effect of PIP. Lyophilized liposomes showed an excellent stability profile with the size range between 189 and 210 nm. Plasma stability study revealed a slight increase in the particle size due to the adsorption of plasma proteins on the surface of liposomes. The long-term stability study also indicated that liposomes were stable at 4°C.


Asunto(s)
Alcaloides/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Benzodioxoles/uso terapéutico , Paclitaxel/uso terapéutico , Piperidinas/uso terapéutico , Alcamidas Poliinsaturadas/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Alcaloides/farmacología , Antineoplásicos Fitogénicos/metabolismo , Antineoplásicos Fitogénicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica , Benzodioxoles/farmacología , Línea Celular Tumoral , Composición de Medicamentos , Estabilidad de Medicamentos , Sinergismo Farmacológico , Receptores ErbB/efectos de los fármacos , Femenino , Liofilización , Humanos , Liposomas , Paclitaxel/metabolismo , Paclitaxel/farmacología , Piperidinas/farmacología , Alcamidas Poliinsaturadas/farmacología , Receptor ErbB-2
12.
Saudi Pharm J ; 28(12): 1616-1625, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33424254

RESUMEN

Drug-resistant tuberculosis (TB) is one of the most lethal diseases, and it is imperative to exploit an advanced drug formulation for its effective treatment. This work aims to develop a mannose receptor-targeted bioadhesive chitosan nanoparticles for effective drug-resistant tuberculosis treatment. The clofazimine loaded chitosan nanoparticles were formulated; their size, charge, polydispersity (PDI), surface morphology, entrapment efficiency (EE) and in-vitro release pattern were established. Also, cellular uptake study on C2C12 cell lines and anti-mycobacterial activity against H37Rv (a standard strain of Mycobacterium tuberculosis) were evaluated. The particle sizes of formulated chitosan nanoparticles were in the range of 132-184 nm and EE was also found to be between 73 and 95%. The functionalization of bioadhesive chitosan nanoparticles with mannose was confirmed by infrared spectroscopy (FTIR). The uptake studies on the C2C12 cell lines showed that mannosylated nanoparticles were more efficiently internalized when compared to non-targeted nanoparticles. Further, luciferase reporter phage (LRP) assay against H37Rv strain showed that clofazimine nanoparticles were found to be 49.5 times superior in terms of inhibition and anti-mycobacterial activity than free clofazimine. This excellent activity might be attributed to enhanced drug delivery with a promising bioadhesion property of chitosan-based nanoparticles.

13.
Cancer ; 125(8): 1258-1266, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30644531

RESUMEN

BACKGROUND: Somatic mutations in hypoxia-inducible factor 2α (HIF2A) are associated with polycythemia-paraganglioma syndrome. Specifically, the classic presentation of female patients with recurrent paragangliomas (PGLs), polycythemia (at birth or in early childhood), and duodenal somatostatinomas has been described. Studies have demonstrated that somatic HIF2A mutations occur as postzygotic events and some to be associated with somatic mosaicism affecting hematopoietic and other tissue precursors. This phenomenon could explain the development of early onset of polycythemia in the absence of erythropoietin-secreting tumors. METHODS: Correlation analysis was performed between mosaicism of HIF2A mutant patients and clinical presentations. RESULTS: Somatic HIF2A mutations (p.A530V, p.P531S, and p.D539N) were identified in DNA extracted from PGLs of 3 patients. No somatic mosaicism was detected through deep sequencing of blood genomic DNA. Compared with classic syndrome, both polycythemia and PGL in all 3 patients developed at an advanced age with polycythemia at age 30, 30, and 17 years and PGLs at age 34, 30, and 55 years, respectively. Somatostatinomas were not detected, and 2 patients had ophthalmic findings. The biochemical phenotype in all 3 patients was noradrenergic with 18 F-fluorodopa PET/CT as the most sensitive imaging modality. All patients demonstrated multiplicity, and none developed metastatic disease. CONCLUSION: These findings suggest that newer techniques need to be developed to detect somatic mosaicism in patients with this syndrome. Absence of HIF2A mosaicism in patients with somatic HIF2A mutations supports association with late onset of the disease, milder clinical phenotype, and an improved prognosis compared with patients who have HIF2A mosaicism.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Paraganglioma/clasificación , Mutación Puntual , Policitemia/clasificación , Adolescente , Adulto , Edad de Inicio , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Persona de Mediana Edad , Mosaicismo , Paraganglioma/diagnóstico por imagen , Paraganglioma/genética , Policitemia/diagnóstico por imagen , Policitemia/genética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Análisis de Secuencia de ADN
14.
Clin Endocrinol (Oxf) ; 89(2): 155-163, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29788534

RESUMEN

CONTEXT: The 68 Ga-labelled somatostatin analogues (68 Ga-DOTA-SSAs) is becoming popular as an important diagnostic tool in neuroendocrine tumours as evidenced by a growing number of reports detailing institutional experience with various DOTA peptides. However, only few prospective studies have compared 68 Ga-DOTA-SSAs and somatostatin receptor scintigraphy (SRS) in gastroenteropancreatic neuroendocrine tumours (GEP-NETs) and pulmonary neuroendocrine tumours. OBJECTIVE: The aim of our prospective study was to perform head-to-head comparison between 68  Ga-DOTATATE PET/CT and standard imaging work-up (SI) that included multiphasic CT, liver MRI and SRS using single photon emission computed tomography. DESIGN: In this prospective study, the patients were enrolled only if they met any of the following inclusion criteria: (i) initial staging of a NETs without distant metastases on SI or neuroendocrine tumour with unknown primary on SI; (ii) restaging of NETs that could be treated by focused therapeutic interventions; (iii) elevated serum neuroendocrine hormones or peptides. The exclusion criteria was grade 3 GEP-NETs. RESULTS: Thirty-two patients were enrolled in the study. Eleven patients (6 pancreas, 4 ileum, 1 duodenal) were included for initial evaluation and staging of NETs, 8 patients (5 pancreas, 1 ileal, 1 lung, 1 duodenal gastrinoma) for restaging, and 13 patients for elevated serum neuroendocrine biomarkers (5 ectopic Cushing's syndrome, 5 organic hypoglycaemia, 1 patient each with elevated vasoactive inhibitory peptide, chromogranin A and neuron-specific enolase). 68 Ga-DOTATATE PET/CT detected more primary tumours than SRS (15/18 vs 10/18: P = .074). The missed tumours on 68 Ga-DOTATATE PET/CT were located in the lung in two cases and duodenum in one case. For other anatomical regions (nodal and distant metastasis), no statistical difference was observed between imaging modalities using 68 Ga-DOTATATE PET/CT and SRS. Overall, 68 Ga-DOTATATE PET/CT+CT+MRI detected 31/33 of the involved regions (including primaries) (29 and 22 for 68 Ga-DOTATATE and SRS, respectively). CONCLUSION: Our study shows that 68 Ga-DOTATATE PET/CT detected similar number of sites than combination of SRS, liver MRI and thoraco-abdominopelvic CT on region-based analysis. 68 Ga-DOTATATE PET/CT missed half of primary lung carcinoids with ectopic Cushing's syndrome.

16.
Eur J Nucl Med Mol Imaging ; 45(5): 787-797, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29204718

RESUMEN

PURPOSE: To evaluate and compare diagnostic performance of 68Ga-DOTA(0)-Tyr(3)-octreotate (68Ga-DOTATATE) with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) and anatomic imaging using computed tomography and/or magnetic resonance (CT/MR) imaging in detection of SDHx-related pheochromocytomas and paragangliomas (PPGLs) in pediatric patients. METHODS: Nine pediatric patients (5:4, girls:boys; 14.6 ± 2.0 years) with an SDHx-related mutation (SDHB:SDHA:SDHD, n = 7:1:1) were included in this retrospective study. At the time of initial diagnosis, 7/9 patients had metastatic disease. They underwent CT/MR imaging along with PET/CT using 68Ga-DOTATATE (n = 9), 18F-FDG (n = 8), and positron emission tomography-magnetic resonance imaging (PET/MR) using 18F-FDG (n = 1). In this manuscript, 18F-FDG PET/CT refers to both 18F-FDG PET/CT and 18F-FDG PET/MR. The per-lesion, per-region, and per-patient detection rates were compared and calculated for each of the imaging modalities. A composite of all functional and anatomic imaging studies served as the imaging comparator. RESULTS: Eight out of nine patients were positive for PPGLs on the imaging studies that demonstrated 107 lesions in 22 anatomic regions on the imaging comparator. The per-lesion detection rates for 68Ga-DOTATATE PET/CT, 18F-FDG PET/CT, and CT/MR imaging were 93.5% (95%CI, 87.0% to 97.3%); 79.4% (95%CI, 70.5% to 86.6%); and 73.8% (95%CI, 64.5% to 81.9%), respectively. The per-lesion detection rate for 68Ga-DOTATATE PET/CT was significantly higher than that of 18F-FDG PET/CT (p = 0.001) or CT/MR imaging (p < 0.001). In all of the anatomic regions except abdomen, the per-lesion detection rates for 68Ga-DOTATATE PET/CT was found to be equal or superior to 18F-FDG PET/CT, and CT/MR imaging. The per-region detection rate was 100% (95%CI, 84.6% to 100%) for 68Ga-DOTATATE PET/CT and 90.9% (95%CI, 70.8% to 98.9%) for both 18F-FDG PET/CT and CT/MR imaging. The per-patient detection rates for 68Ga-DOTATATE PET/CT, 18FDG PET/CT, and CT/MR imaging were all 100% (95%CI, 63.1% to 100%). CONCLUSION: Our preliminary study demonstrates the superiority of 68Ga-DOTATATE PET/CT in localization of SDHx-related PPGLs in pediatric population compared to 18F-FDG PET/CT and CT/MR imaging with the exception of abdominal (excluding adrenal and liver) lesions, and suggests that it might be considered as a first-line imaging modality in pediatric patients with SDHx-related PPGLs.


Asunto(s)
Mutación , Compuestos Organometálicos , Paraganglioma/genética , Feocromocitoma/genética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Succinato Deshidrogenasa/genética , Adolescente , Niño , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Paraganglioma/diagnóstico por imagen , Feocromocitoma/diagnóstico por imagen , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
17.
Nucleic Acids Res ; 44(W1): W194-200, 2016 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-27098040

RESUMEN

Novel techniques for high-throughput steady-state metabolomic profiling yield information about changes of nearly thousands of metabolites. Such metabolomic profiles, when analyzed together with transcriptional profiles, can reveal novel insights about underlying biological processes. While a number of conceptual approaches have been developed for data integration, easily accessible tools for integrated analysis of mammalian steady-state metabolomic and transcriptional data are lacking. Here we present GAM ('genes and metabolites'): a web-service for integrated network analysis of transcriptional and steady-state metabolomic data focused on identification of the most changing metabolic subnetworks between two conditions of interest. In the web-service, we have pre-assembled metabolic networks for humans, mice, Arabidopsis and yeast and adapted exact solvers for an optimal subgraph search to work in the context of these metabolic networks. The output is the most regulated metabolic subnetwork of size controlled by false discovery rate parameters. The subnetworks are then visualized online and also can be downloaded in Cytoscape format for subsequent processing. The web-service is available at: https://artyomovlab.wustl.edu/shiny/gam/.


Asunto(s)
Algoritmos , Redes y Vías Metabólicas/genética , Metaboloma/genética , Programas Informáticos , Transcripción Genética , Animales , Arabidopsis/genética , Línea Celular Tumoral , Gráficos por Computador , Bases de Datos Genéticas , Células Epiteliales/metabolismo , Células Epiteliales/patología , Humanos , Internet , Activación de Macrófagos/genética , Activación de Macrófagos/inmunología , Macrófagos/citología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Cultivo Primario de Células , Saccharomyces cerevisiae/genética , Especificidad de la Especie
18.
AAPS PharmSciTech ; 19(4): 1894-1907, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29663289

RESUMEN

The elevated blood levels of cholesterol and low-density lipoproteins result in hyperlipidemia. The available expensive prophylactic treatments are kindred with severe side effects. Therefore, we fabricated the polymeric nanoparticles of gamma-oryzanol to achieving the improved efficacy of drug. The nanoparticles were prepared by ionic gelation method and optimized using 23 full factorial design taking drug/polymer ratio (X1), polymer/cross linking agent ratio (X2), and stirring speed (X3) as independent variables. The average particle size, percentage entrapment efficiency, and in vitro drug release at 2, 12, and 24 h were selected as response parameters. The factorial batches were statistically analyzed and optimized. The optimized nanoparticles were characterized with respect to particle size (141 nm) and zeta potential (+ 6.45 mV). Results obtained with the prepared and characterized formulation showed 83% mucoadhesion towards the intestinal mucosa. The in vitro findings were complemented well by in vivo anti-hyperlipidemic activity of developed formulation carried out in Swiss albino mouse model. The in vivo studies showed improved atherogenic index, malondialdehyde, and superoxide dismutase levels in poloxamer-407-induced hyperlipidemic animals when treated with oryzanol and gamma-oryzanol nanoformulation. Based on our findings, we believe that chitosan-mediated delivery of gamma-oryzanol nanoparticles might prove better in terms of anti-hyperlipidemic therapeutics.


Asunto(s)
Quitosano/metabolismo , Hipolipemiantes/metabolismo , Nanopartículas/metabolismo , Fenilpropionatos/metabolismo , Animales , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/metabolismo , Quitosano/administración & dosificación , Quitosano/química , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Composición de Medicamentos , Evaluación Preclínica de Medicamentos/métodos , Hipolipemiantes/administración & dosificación , Hipolipemiantes/química , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Masculino , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/química , Tamaño de la Partícula , Fenilpropionatos/administración & dosificación , Fenilpropionatos/química , Ratas
19.
Nature ; 476(7360): 346-50, 2011 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-21760589

RESUMEN

Cancer cells adapt their metabolic processes to drive macromolecular biosynthesis for rapid cell growth and proliferation. RNA interference (RNAi)-based loss-of-function screening has proven powerful for the identification of new and interesting cancer targets, and recent studies have used this technology in vivo to identify novel tumour suppressor genes. Here we developed a method for identifying novel cancer targets via negative-selection RNAi screening using a human breast cancer xenograft model at an orthotopic site in the mouse. Using this method, we screened a set of metabolic genes associated with aggressive breast cancer and stemness to identify those required for in vivo tumorigenesis. Among the genes identified, phosphoglycerate dehydrogenase (PHGDH) is in a genomic region of recurrent copy number gain in breast cancer and PHGDH protein levels are elevated in 70% of oestrogen receptor (ER)-negative breast cancers. PHGDH catalyses the first step in the serine biosynthesis pathway, and breast cancer cells with high PHGDH expression have increased serine synthesis flux. Suppression of PHGDH in cell lines with elevated PHGDH expression, but not in those without, causes a strong decrease in cell proliferation and a reduction in serine synthesis. We find that PHGDH suppression does not affect intracellular serine levels, but causes a drop in the levels of α-ketoglutarate, another output of the pathway and a tricarboxylic acid (TCA) cycle intermediate. In cells with high PHGDH expression, the serine synthesis pathway contributes approximately 50% of the total anaplerotic flux of glutamine into the TCA cycle. These results reveal that certain breast cancers are dependent upon increased serine pathway flux caused by PHGDH overexpression and demonstrate the utility of in vivo negative-selection RNAi screens for finding potential anticancer targets.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Genómica , Serina/biosíntesis , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Ciclo del Ácido Cítrico/fisiología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Ácido Glutámico/metabolismo , Humanos , Ácidos Cetoglutáricos/metabolismo , Melanoma/enzimología , Melanoma/genética , Ratones , Trasplante de Neoplasias , Fosfoglicerato-Deshidrogenasa/genética , Fosfoglicerato-Deshidrogenasa/metabolismo , Interferencia de ARN
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