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1.
Curr Med Imaging ; 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37489788

RESUMEN

BACKGROUND: It has been reported that structure damage in the parenchymal lung disease such as idiopathic pulmonary fibrosis (IPF) is associated with high susceptibility to nontuberculous mycobacterial (NTM) infection. Radiologic features of NTM lung disease in destructive lung parenchyma can be atypical, which can cause confusion with other diseases including malignancy. Prompt and accurate identification of newly developed lesions in the follow-up computed tomography (CT) of IPF patients is challenging but crucial. CASE REPORT: We reported a case of an NTM infection in a patient with IPF, manifested as a mass-like consolidation with cavitation on chest CT, mimicking lung cancer. CONCLUSION: Being aware of the unusual radiologic features of NTM lung disease in IPF patients can be useful in the differential diagnosis of newly detected lesions.

2.
J Nanobiotechnology ; 20(1): 330, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-35842630

RESUMEN

BACKGROUND: Radiodynamic therapy (RDT) holds the potential to overcome the shallow tissue penetration issue associated with conventional photodynamic therapy (PDT). To this end, complex and sometimes toxic scintillator-photosensitizer nanoconjugates are often used, posing barriers for large-scale manufacturing and regulatory approval. METHODS: Herein, we report a streamlined RDT strategy based on CsI(Na)@MgO nanoparticles and 5-aminolevulinic acid (5-ALA). 5-ALA is a clinically approved photosensitizer, converted to protoporphyrin IX (PpIX) in cancer cells' mitochondria. CsI(Na)@MgO nanoparticles produce strong ~ 410 nm X-ray luminescence, which matches the Soret band of PpIX. We hypothesize that the CsI(Na)@MgO-and-5-ALA combination can mediate RDT wherein mitochondria-targeted PDT synergizes with DNA-targeted irradiation for efficient cancer cell killing. Because scintillator nanoparticles and photosensitizer are administered separately, the approach forgoes issues such as self-quenching or uncontrolled release of photosensitizers. RESULTS: When tested in vitro with 4T1 cells, the CsI(Na)@MgO and 5-ALA combination elevated radiation-induced reactive oxygen species (ROS), enhancing damages to mitochondria, DNA, and lipids, eventually reducing cell proliferation and clonogenicity. When tested in vivo in 4T1 models, RDT with the CsI(Na)@MgO and 5-ALA combination significantly improved tumor suppression and animal survival relative to radiation therapy (RT) alone. After treatment, the scintillator nanoparticles, made of low-toxic alkali and halide elements, were efficiently excreted, causing no detectable harm to the hosts. CONCLUSIONS: Our studies show that separately administering CsI(Na)@MgO nanoparticles and 5-ALA represents a safe and streamlined RDT approach with potential in clinical translation.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Ácido Aminolevulínico/farmacología , Animales , Línea Celular Tumoral , Óxido de Magnesio , Nanopartículas/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico
3.
Membranes (Basel) ; 12(3)2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35323794

RESUMEN

The wide-scale use of liposomal delivery systems is challenged by difficulties in obtaining potent liposomal suspensions. Passive and active loading strategies have been proposed to formulate drug encapsulated liposomes but are limited by low efficiencies (passive) or high drug specificities (active). Here, we present an efficient and universal loading strategy for synthesizing therapeutic liposomes. Integrating a thermal equilibration technique with our unique liposome synthesis approach, co-loaded targeting nanovesicles can be engineered in a scalable manner with potencies 200-fold higher than typical passive encapsulation techniques. We demonstrate this capability through simultaneous co-loading of hydrophilic and hydrophobic small molecules and targeted delivery of liposomal Doxorubicin to metastatic breast cancer cell line MDA-MB-231. Molecular dynamic simulations are used to explain interactions between Doxorubicin and liposome membrane during thermal equilibration. By addressing the existing challenges, we have developed an unparalleled approach that will facilitate the formulation of novel theranostic and pharmaceutical strategies.

4.
Small ; 18(17): e2200710, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35304816

RESUMEN

Therapeutics that can be activated by radiation in situ to enhance the efficacy of radiotherapy are highly desirable. Herein, 7-Dehydrocholesterol (7-DHC), a biosynthetic precursor of cholesterol, as a radiosensitizer, exploiting its ability to propagate the free radical chain reaction is explored. The studies show that 7-DHC can react with radiation-induced reactive oxygen species and in turn promote lipid peroxidation, double-strand breaks, and mitochondrial damage in cancer cells. For efficient delivery, 7-DHC is encapsulated into poly(lactic-co-glycolic acid) nanoparticles, forming 7-DHC@PLGA NPs. When tested in CT26 tumor bearing mice, 7-DHC@PLGA NPs significantly enhanced the efficacy of radiotherapy, causing complete tumor eradication in 30% of the treated animals. After treatment, 7-DHC is converted to cholesterol, causing no detectable side effects or hypercalcemia. 7-DHC@PLGA NPs represent a radiation-responsive sensitizer with great potential in clinical translation.


Asunto(s)
Nanopartículas , Neoplasias , Fármacos Sensibilizantes a Radiaciones , Animales , Línea Celular Tumoral , Deshidrocolesteroles , Ácido Láctico , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/uso terapéutico
7.
ACS Nano ; 15(11): 17401-17411, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34694109

RESUMEN

Iodine has shown promise in enhancing radiotherapy. However, conventional iodine compounds show fast clearance and low retention inside cancer cells, limiting their application as a radiosensitizer. Herein, we synthesize poly(maleic anhydride-alt-1-octadecene) coated KI nanoparticles (PMAO-KI NPs) and evaluate their potential for enhancing radiotherapy. Owing to the polymer coating, the KI core of PMAO-KI NPs is not instantly dissolved in aqueous solutions but slowly degraded, allowing for controlled release of iodide (I-). I- is transported into cells via the sodium iodide symporter (NIS), which is upregulated in breast cancer cells. Our results show that PMAO-KI NPs can enhance radiation-induced production of reactive oxygen species such as hydroxyl radicals. When tested in vitro with MCF-7 cells, PMAO-KI NPs promote radiation-induced DNA double-strand breaks and lipid peroxidation, causing a drop in cancer cell viability and reproductivity. When tested in MCF-7 bearing mice, PMAO-KI NPs show significant radiosensitizing effects, leading to complete tumor eradication in 80% of the treated animals without inducing additional toxicity. Overall, our strategy exploits electrolyte nanoparticles to deliver iodide into cancer cells through NIS, thus promoting radiotherapy against breast cancer.


Asunto(s)
Nanopartículas , Neoplasias , Animales , Ratones , Yoduros/metabolismo , Yoduro de Potasio , Línea Celular Tumoral , Tretinoina/farmacología
8.
J Nanobiotechnology ; 19(1): 284, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34551763

RESUMEN

BACKGROUND: Recently, gadolinium-intercalated carbon dots (Gd@C-dots) have demonstrated potential advantages over traditional high-Z nanoparticles (HZNPs) as radiosensitizers due to their high stability, minimal metal leakage, and remarkable efficacy. RESULTS: In this work, two Gd@C-dots formulations were fabricated which bore carboxylic acid (CA-Gd@C-dots) or amino group (pPD-Gd@C-dots), respectively, on the carbon shell. While it is critical to develop innovative nanomateirals for cancer therapy, determining their tumor accumulation and retention is equally important. Therefore, in vivo positron emission tomography (PET) was performed, which found that 64Cu-labeled pPD-Gd@C-dots demonstrated significantly improved tumor retention (up to 48 h post injection) compared with CA-Gd@C-dots. Indeed, cell uptake of 64Cu-pPD-Gd@C-dots reached close to 60% of total dose compared with ~ 5% of 64Cu-CA-Gd@C-dots. pPD-Gd@C-dots was therefore further evaluated as a new radiosensitizer for non-small cell lung cancer treatment. While single dose radiation plus intratumorally injected pPD-Gd@C-dots did lead to improved tumor suppression, the inhibition effect was further improved with two doses of radiation. The persistent retention of pPD-Gd@C-dots in tumor region eliminates the need of reinjecting radiosensitizer for the second radiation. CONCLUSIONS: PET offers a simple and straightforward way to study nanoparticle retention in vivo, and the selected pPD-Gd@C-dots hold great potential as an effective radiosensitizer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Gadolinio/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Nanopartículas/uso terapéutico , Animales , Carbono , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Medios de Contraste , Femenino , Gadolinio/química , Gadolinio/uso terapéutico , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Ratones Desnudos , Nanopartículas/química , Tomografía de Emisión de Positrones/métodos , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/uso terapéutico
10.
Nanoscale ; 13(20): 9252-9263, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33982686

RESUMEN

High-Z nanoparticles (HZNPs) afford high cross-section for high energy radiation and have attracted wide attention as a novel type of radiosensitizer. However, conventional HZNPs are often associated with issues such as heavy metal toxicity, suboptimal pharmacokinetics, and low cellular uptake. Herein, we explore gadolinium-intercalated carbon dots (Gd@Cdots) as a dose-modifying agent for radiotherapy. Gd@Cdots are synthesized through a hydrothermal reaction with an ultrasmall size (∼3 nm) and a high Gd content. Gd@Cdots can significantly increase hydroxyl radical production under X-ray irradiation; this is attributed to not only the photoelectric effects of Gd, but also the surface catalytic effects of carbon. Because carbon is biologically and chemically inert, Gd@Cdots show low Gd leakage and minimal toxicity. In vitro studies confirm that Gd@Cdots can efficiently enhance radiation-induced cellular damage, causing elevated double strand breaks, lipid peroxidation, and mitochondrial depolarization. When tested in mice bearing non-small cell lung cancer H1299 tumors, intravenously injected Gd@Cdots plus radiation leads to improved tumor suppression and animal survival relative to radiation alone while causing no detectable toxicity. Our studies suggest a great potential of Gd@Cdots as a safe and efficient radiosensitizer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Fármacos Sensibilizantes a Radiaciones , Animales , Carbono , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Gadolinio , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Fármacos Sensibilizantes a Radiaciones/farmacología
11.
Sci Rep ; 11(1): 6359, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33737673

RESUMEN

Tilia species are valuable woody species due to their beautiful shape and role as honey trees. Somatic embryogenesis can be an alternative method for mass propagation of T. amurensis. However, the molecular mechanisms of T. amurensis somatic embryogenesis are yet to be known. Here, we conducted comparative transcriptional analysis during somatic embryogenesis of T. amurensis. RNA-Seq identified 1505 differentially expressed genes, including developmental regulatory genes. Auxin related genes such as YUC, AUX/IAA and ARF and signal transduction pathway related genes including LEA and SERK were differentially regulated during somatic embryogenesis. Also, B3 domain family (LEC2, FUS3), VAL and PKL, the regulatory transcription factors, were differentially expressed by somatic embryo developmental stages. Our results could provide plausible pathway of signaling somatic embryogenesis of T. amurensis, and serve an important resource for further studies in direct somatic embryogenesis in woody plants.


Asunto(s)
Desarrollo de la Planta/genética , Técnicas de Embriogénesis Somática de Plantas , Tilia/genética , Transcriptoma/genética , Regulación del Desarrollo de la Expresión Génica/genética , Regulación de la Expresión Génica de las Plantas/genética , Reguladores del Crecimiento de las Plantas/genética , Proteínas de Plantas/genética , RNA-Seq , Regeneración/genética , Transducción de Señal/genética , Tilia/crecimiento & desarrollo
12.
J Nanobiotechnology ; 18(1): 131, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32917209

RESUMEN

BACKGROUND: Radiation therapy is a main treatment option for cancer. Due to normal tissue toxicity, radiosensitizers are commonly used to enhance RT. In particular, heavy metal or high-Z materials, such as gold nanoparticles, have been investigated as radiosensitizers. So far, however, the related studies have been focused on spherical gold nanoparticles. In this study, we assessed the potential of ultra-thin gold nanowires as a radiosensitizer, which is the first time. METHODS: Gold nanowires were synthesized by the reduction of HAuCl4 in hexane. The as-synthesized gold nanowires were then coated with a layer of PEGylated phospholipid to be rendered soluble in water. Spherical gold nanoparticles coated with the same phospholipid were also synthesized as a comparison. Gold nanowires and gold nanospheres were first tested in solutions for their ability to enhance radical production under irradiation. They were then incubated with 4T1 cells to assess whether they could elevate cell oxidative stress under irradiation. Lastly, gold nanowires and gold nanoparticles were intratumorally injected into a 4T1 xenograft model, followed by irradiation applied to tumors (3 Gy/per day for three days). Tumor growth was monitored and compared. RESULTS: Our studies showed that gold nanowires are superior to gold nanospheres in enhancing radical production under X-ray radiation. In vitro analysis found that the presence of gold nanowires caused elevated lipid peroxidation and intracellular oxidative stress under radiation. When tested in vivo, gold nanowires plus irradiation led to better tumor suppression than gold nanospheres plus radiation. Moreover, gold nanowires were found to be gradually reduced to shorter nanowires by glutathione, which may benefit fractionated radiation. CONCLUSION: Our studies suggest that gold nanowires are a promising type of radiosensitizer that can be safely injected into tumors to enhance radiotherapy. While the current study was conducted in a breast cancer model, the approach can be extended to the treatment of other cancer types.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanocables/química , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Animales , Neoplasias de la Mama , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Radicales Libres , Hexanos , Nanopartículas del Metal/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Nanosferas , Oxígeno , Radioterapia , Ensayos Antitumor por Modelo de Xenoinjerto
13.
J Exerc Rehabil ; 16(2): 115-117, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32509694

RESUMEN

Hyperglycemic diabetes is a chronic metabolic disorder characterized by high level of plasma glucose. Numerous studies have shown that hy-perglycemic diabetes leads to brain dysfunction including cognitive im-pairment and emotional disorders. This study evaluated the impact of exercise on brain dysfunction, hippocampal neurogenesis, and cogni-tive impairment in hyperglycemic diabetes. The present study suggests that exercise improves hyperglycemic control and prevents decline of cognition through increasing hippocampal neurogenesis. Understanding the mechanism of exercise for hippocampal neurogenesis can lead to the development of therapeutic strategies for metabolic disorders.

14.
ACS Nano ; 14(2): 1468-1481, 2020 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-31939662

RESUMEN

Radiotherapy remains a major treatment modality for cancer types such as non-small cell lung carcinoma (or NSCLC). To enhance treatment efficacy at a given radiation dose, radiosensitizers are often used during radiotherapy. Herein, we report a nanoparticle agent that can selectively sensitize cancer cells to radiotherapy. Specifically, we nitrosylated maytansinoid DM1 and then loaded the resulting prodrug, DM1-NO, onto poly(lactide-co-glycolic)-block-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles. The toxicity of DM1 is suppressed by nanoparticle encapsulation and nitrosylation, allowing the drug to be delivered to tumors through the enhanced permeability and retention effect. Under irradiation to tumors, the oxidative stress is elevated, leading to the cleavage of the S-N bond and the release of DM1 and nitric oxide (NO). DM1 inhibits microtubule polymerization and enriches cells at the G2/M phase, which is more radiosensitive. NO under irradiation forms highly toxic radicals such as peroxynitrites, which also contribute to tumor suppression. The two components work synergistically to enhance radiotherapy outcomes, which was confirmed in vitro by clonogenic assays and in vivo with H1299 tumor-bearing mice. Our studies suggest the great promise of DM1-NO PLGA nanoparticles in enhancing radiotherapy against NSCLC and potentially other tumor types.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Maitansina/farmacología , Nanopartículas/química , Animales , Antineoplásicos Fitogénicos/química , Cápsulas/química , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Maitansina/química , Ratones , Ratones Desnudos , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Estrés Oxidativo/efectos de los fármacos , Tamaño de la Partícula , Propiedades de Superficie , Células Tumorales Cultivadas
15.
Trends Chem ; 2(12): 1082-1095, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35178514

RESUMEN

Phototherapy, including photodynamic therapy and photothermal therapy, exploits light to activate photo-reactions that kill cancer cells. Recent studies show that phototherapy can not only kill irradiated tumor cells, but also elicit a tumor specific immune response. This phenomenon breaks the limitations of conventional phototherapy, and has reinvigorated phototherapy-related research in the era of cancer immunotherapy. Nanoparticles play essential roles in this new campaign for allowing simultaneous delivery of photo-reactive agents and immune modulators. Some nanoparticles are potent adjuvants on their own and can augment anticancer immunity to fight off tumor relapse and metastasis. In this review, we summarize recent advances on exploiting nanoparticle-based photodynamic therapy and photothermal therapy for cancer immunotherapy, with an emphasis on nanoplatform design and functions.

16.
Adv Mater ; 30(50): e1805557, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30368972

RESUMEN

Macrophages hold great potential in cancer drug delivery because they can sense chemotactic cues and home to tumors with high efficiency. However, it remains a challenge to load large amounts of therapeutics into macrophages without compromising cell functions. This study reports a silica-based drug nanocapsule approach to solve this issue. The nanocapsule consists of a drug-silica complex filling and a solid silica sheath, and it is designed to minimally release drug molecules in the early hours of cell entry. While taken up by macrophages at high rates, the nanocapsules minimally affect cell migration in the first 6-12 h, buying time for macrophages to home to tumors and release drugs in situ. In particular, it is shown that doxorubicin (Dox) as a representative drug can be loaded into macrophages up to 16.6 pg per cell using this approach. When tested in a U87MG xenograft model, intravenously (i.v.) injected Dox-laden macrophages show comparable tumor accumulation as untreated macrophages. Therapy leads to efficient tumor growth suppression, while causing little systematic toxicity. This study suggests a new cell platform for selective drug delivery, which can be readily extended to the treatment of other types of diseases.


Asunto(s)
Doxorrubicina/química , Portadores de Fármacos/química , Nanopartículas/química , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Humanos , Inyecciones Intraventriculares , Estimación de Kaplan-Meier , Macrófagos/citología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Neoplasias/mortalidad , Neoplasias/patología , Tomografía de Emisión de Positrones , Células RAW 264.7 , Dióxido de Silicio/química , Trasplante Heterólogo
17.
J Exerc Rehabil ; 10(5): 252-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25426460

RESUMEN

Attention-deficit/hyperactivity disorder (ADHD) involves clinically heterogeneous dysfunctions of sustained attention, with behavioral hyper-activity and impulsivity. The exact underlying mechanisms of ADHD are not known, however, impairment of dopaminergic system in the nigrostriatal pathway was suggested as the one of the possible mechanisms of ADHD. Tyrosine hydroxylase (TH) is the rate-limiting enzyme that is involved in the synthesis of dopamine. Spontaneous hypertensive rats have been used as the animal model for ADHD. Physical exercise is known to restore the brain functions disrupted by several neurode-generative and psychiatric disorders. In the present study, we investigated whether treadmill exercise exerts therapeutic effect on ADHD. Social interaction test for the evaluation of impulsivity was performed using spontaneous hypertensive rats. TH expressions in the substantia nigra and striatum were evaluated by immunohistochemistry. In the present results, the rats of ADHD model showed hyper-social behaviors. TH expressions in the substantia nigra and striatum were decreased in the rats of ADHD model. Treadmill exercise alleviated hyper-social behaviors in the ADHD rats. TH expressions of ADHD rats were also enhanced by treadmill exercise. Here in this study, we showed that treadmill exercise effectively alleviates the ADHD-induced symptoms through enhancing of TH expression in the brain.

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