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1.
J Nanobiotechnology ; 20(1): 177, 2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-35366888

RESUMEN

BACKGROUND: Small interfering RNA (siRNA) is utilized as a potent agent for cancer therapy through regulating the expression of genes associated with tumors. While the widely application of siRNAs in cancer treatment is severely limited by their insufficient biological stability and its poor ability to penetrate cell membranes. Targeted delivery systems hold great promise to selectively deliver loaded drug to tumor site and reduce toxic side effect. However, the elevated tumor interstitial fluid pressure and efficient cytoplasmic release are still two significant obstacles to siRNA delivery. Co-delivery of chemotherapeutic drugs and siRNA represents a potential strategy which may achieve synergistic anticancer effect. Herein, we designed and synthesized a dual pH-responsive peptide (DPRP), which includes three units, a cell-penetrating domain (polyarginine), a polyanionic shielding domain (ehG)n, and an imine linkage between them. Based on the DPRP surface modification, we developed a pH-responsive liposomal system for co-delivering polo-like kinase-1 (PLK-1) specific siRNA and anticancer agent docetaxel (DTX), D-Lsi/DTX, to synergistically exhibit anti-tumor effect. RESULTS: In contrast to the results at the physiological pH (7.4), D-Lsi/DTX lead to the enhanced penetration into tumor spheroid, the facilitated cellular uptake, the promoted escape from endosomes/lysosomes, the improved distribution into cytoplasm, and the increased cellular apoptosis under mildly acidic condition (pH 6.5). Moreover, both in vitro and in vivo study indicated that D-Lsi/DTX had a therapeutic advantage over other control liposomes. We provided clear evidence that liposomal system co-delivering siPLK-1 and DTX could significantly downregulate expression of PLK-1 and inhibit tumor growth without detectable toxic side effect, compared with siPLK-1-loaded liposomes, DTX-loaded liposomes, and the combinatorial administration. CONCLUSION: These results demonstrate great potential of the combined chemo/gene therapy based on the multistage pH-responsive codelivery liposomal platform for synergistic tumor treatment.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/química , Docetaxel/farmacología , Concentración de Iones de Hidrógeno , Liposomas/química , Neoplasias/tratamiento farmacológico , ARN Interferente Pequeño
2.
Pharm Dev Technol ; 23(6): 573-586, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27824281

RESUMEN

Polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer, or Soluplus®, is a relatively new copolymer and a promising carrier of amorphous solid dispersions. Knowledge on the inherent properties of Soluplus® (e.g. cloud points, critical micelle concentrations, and viscosity) in different conditions is relatively inadequate, and the application characteristics of Soluplus®-based solid dispersions made by microwave methods still need to be clarified. In the present investigation, the inherent properties of a Soluplus® carrier, including cloud points, critical micelle concentrations, and viscosity, were explored in different media and in altered conditions. Ibuprofen, a BCS class II non-steroidal anti-inflammatory drug, was selected to develop Soluplus®-based amorphous solid dispersions using the microwave-quench cooling (MQC) method. Scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Raman spectroscopy (RS), and Fourier transform infrared spectroscopy (FT-IR) were adopted to analyze amorphous properties and molecular interactions in ibuprofen/Soluplus® amorphous solid dispersions generated by MQC. Dissolution, dissolution extension, phase solubility, equilibrium solubility, and supersaturated crystallization inhibiting experiments were performed to elucidate the effects of Soluplus® on ibuprofen in solid dispersions. This research provides valuable information on the inherent properties of Soluplus® and presents a basic understanding of Soluplus® as a carrier of amorphous solid dispersions.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Portadores de Fármacos/química , Composición de Medicamentos/métodos , Ibuprofeno/administración & dosificación , Polietilenglicoles/química , Polivinilos/química , Antiinflamatorios no Esteroideos/química , Cristalización , Ibuprofeno/química , Micelas , Microondas , Transición de Fase , Solubilidad , Viscosidad , Difracción de Rayos X
3.
AAPS PharmSciTech ; 20(1): 12, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30560388

RESUMEN

The collective impact of cellulosic polymers on the dissolution, solubility, and crystallization inhibition of amorphous active pharmaceutical ingredients (APIs) is still far from being adequately understood. The goal of this research was to explore the influence of cellulosic polymers and incubation conditions on enhancement of solubility and dissolution of amorphous felodipine, while inhibiting crystallization of the drug from a supersaturated state. Variables, including cellulosic polymer type, amount, ionic strength, and viscosity, were evaluated for effects on API dissolution/solubility and crystallization processes. Water-soluble cellulosic polymers, including HPMC E15, HPMC E5, HPMC K100-LV, L-HPC, and MC, were studied. All cellulosic polymers could extend API dissolution and solubility to various extents by delaying crystallization and prolonging supersaturation duration, with their effectiveness ranked from greatest to least as HPMC E15 > HPMC E5 > HPMC K100-LV > L-HPC > MC. Decreased polymer amount, lower ionic strength, or higher polymer viscosity tended to decrease dissolution/solubility and promote crystal growth to accelerate crystallization. HPMC E15 achieved greatest extended API dissolution and maintenance of supersaturation from a supersaturated state; this polymer thus had the greatest potential for maintaining sustainable API absorption within biologically relevant time frames.


Asunto(s)
Felodipino/química , Cristalización , Polímeros/química , Solubilidad , Viscosidad
4.
Mol Pharm ; 14(4): 1012-1022, 2017 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-28252970

RESUMEN

For aggressive brain glioblastoma, the therapy is significantly impaired by blood-brain barrier (BBB) and blood-tumor barrier (BTB). Choosing more than one target from the pool of tumor-stroma interactions is profoundly beneficial to therapeutic approaches. Thus, a multifunctional liposomal system based on anchoring two receptor-specific and penetrable peptides was designed for the combination delivery of BBB-impermeable siRNA and chemotherapeutic docetaxel to brain glioblastoma. Both macroscopic and microscopic specific distributions and targeting effect of the liposomes in the intracranial glioblastoma were confirmed. Superiority in therapeutic efficacies of the siRNA and DTX combination delivery system was revealed from encouraged VEGF gene silencing, tumor cell apoptosis, prolonged survival time, subdued glioblastoma cells in intracranial glioblastoma, and negligible system toxicities after systemic application. Furthermore, the liposomes made better modulation of glioblastoma microenvironment such as the down-regulation of CD31-positive tumor vessels and HIF-1α expression. The transport mechanism of the liposomes delivering the cargos across BBB via receptor-mediated transcytosis without destroying the integrity of BBB has been evaluated from in vitro and in vivo. Therefore, the dual peptides-modified liposomal system provides a safe and noninvasive approach for the delivery of siRNA and chemotherapeutic molecules across the BBB and BTB to target therapy of brain glioblastoma.


Asunto(s)
Antineoplásicos/administración & dosificación , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , ARN Interferente Pequeño/administración & dosificación , Microambiente Tumoral/fisiología , Animales , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Docetaxel , Regulación hacia Abajo/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Glioblastoma/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Liposomas/administración & dosificación , Ratones , Péptidos/metabolismo , Taxoides/administración & dosificación , Factor A de Crecimiento Endotelial Vascular/metabolismo
5.
Molecules ; 21(9)2016 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-27563865

RESUMEN

Parkinson's disease (PD) is a major age-related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra par compacta (SNpc). Rotenone is a neurotoxin that is routinely used to model PD to aid in understanding the mechanisms of neuronal death. Safflower (Carthamus tinctorius. L.) has long been used to treat cerebrovascular diseases in China. This plant contains flavonoids, which have been reported to be effective in models of neurodegenerative disease. We previously reported that kaempferol derivatives from safflower could bind DJ-1, a protein associated with PD, and that a flavonoid extract from safflower exhibited neuroprotective effects in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of PD. In this study, a standardized safflower flavonoid extract (SAFE) was isolated from safflower and found to primarily contain flavonoids. The aim of the current study was to confirm the neuroprotective effects of SAFE in rotenone-induced Parkinson rats. The results showed that SAFE treatment increased body weight and improved rearing behavior and grip strength. SAFE (35 or 70 mg/kg/day) treatment reversed the decreased protein expression of tyrosine hydroxylase, dopamine transporter and DJ-1 and increased the levels of dopamine and its metabolite. In contrast, acetylcholine levels were decreased. SAFE treatment also led to partial inhibition of PD-associated changes in extracellular space diffusion parameters. These changes were detected using a magnetic resonance imaging (MRI) tracer-based method, which provides novel information regarding neuronal loss and astrocyte activation. Thus, our results indicate that SAFE represents a potential therapeutic herbal treatment for PD.


Asunto(s)
Carthamus tinctorius/química , Flavonoides , Fármacos Neuroprotectores , Enfermedad de Parkinson Secundaria/tratamiento farmacológico , Enfermedad de Parkinson Secundaria/metabolismo , Extractos Vegetales , Animales , Flavonoides/química , Flavonoides/farmacología , Flavonoides/normas , Ratones , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/normas , Enfermedad de Parkinson Secundaria/inducido químicamente , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/normas , Ratas , Rotenona/toxicidad
6.
Yao Xue Xue Bao ; 51(3): 462-8, 2016 03.
Artículo en Zh | MEDLINE | ID: mdl-29859030

RESUMEN

This study aims to explore the characteristics of crystallization inhibition by cellulose polymers at the supersaturated states of drugs. The study was performed by simulating supersaturated process and preparing supersaturated drug solid, and was carried out by measuring the content of drugs at different time points using dissolution apparatus. The types, amounts, ionic intensity and viscosity of cellulose polymers were examined to assess the crystallization inhibition effect on BCS II class drug indomethacin. HPMC E15 exhibited the strongest crystallization inhibition effect. The more added, more obvious crystallization suppression was observed against indomethacin. The decrease in viscosity and increase in ionic intensity led to an enhanced inhibition. The research provides a scientific guide for the crystallization inhibition of supersaturated drug by cellulose polymers.


Asunto(s)
Celulosa/química , Composición de Medicamentos , Indometacina/química , Polímeros/química , Cristalización , Solubilidad , Viscosidad
7.
Yao Xue Xue Bao ; 51(4): 529-35, 2016 04.
Artículo en Zh | MEDLINE | ID: mdl-29859520

RESUMEN

Cell-penetrating peptides are composed of positively-charged amino acids that can mediate molecules or nano-carriers across cell membranes. However, most of the known cell-penetrating peptides have no cell- or tissue-specificity, with affinity to almost all types of cells in internalization. The non-specificity of cell-penetrating peptides is a significant obstacle in the application to targeted delivery of imaging probes and therapeutic agents. Accordingly, many studies focused on selective switching of systemically-delivered inert cell-penetrating peptides into active forms in diseased tissues. Tsien groups introduced the concept of activatable cell-penetrating peptides in 2004. Subsequently, a growing number of similar delivery systems(molecular or nano-sized) have been documented, and the sensitive factors have included enzyme, lower p H, light and exogenous component. In this paper, we make an overview of the development of activatable delivery system in recent years.


Asunto(s)
Péptidos de Penetración Celular/química , Sistemas de Liberación de Medicamentos , Animales , Membrana Celular , Humanos
8.
Mol Pharm ; 12(6): 2189-202, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25945733

RESUMEN

Multidrug resistance (MDR) presents a clinical obstacle to cancer chemotherapy. The main purpose of this study was to evaluate the potential of a hyaluronic acid (HA) and α-tocopheryl succinate (α-TOS) based nanoparticle to enhance cancer cell recognition and overcome MDR, and to explore the underlying mechanisms. A multifunctional nanoparticle, HTTP-50 NP, consisted of HA-α-TOS (HT) conjugate and d-α-tocopheryl polyethylene glycol succinate (TPGS) with docetaxel loaded in its hydrophobic core. The promoted tumor cell recognition and accumulation, cytotoxicity, and mitochondria-specific apoptotic pathways for the HTTP-50 NP were confirmed in MCF-7/Adr cells (P-gp-overexpressing cancer model), indicating that the formulated DTX and the conjugated α-TOS in the HTTP-50 NP could synergistically circumvent the acquired and intrinsic MDR in MCF-7/Adr cells. In vivo investigation on the MCF-7/Adr xenografted nude mice models confirmed that HTTP-50 NP possessed much higher tumor tissue accumulation and exhibited pronouncedly enhanced antiresistance tumor efficacy with reduced systemic toxicity compared with HTTP-0 NP and Taxotere. The mechanisms of the multifunctional HTTP-50 NP to overcome MDR and enhance antiresistance efficacy may be contributed by CD44 receptor-targeted delivery and P-gp efflux inhibition, and meanwhile to maximize antitumor efficacy by synergism of DTX and mitocan of α-TOS killing tumor cells.


Asunto(s)
Ácido Hialurónico/química , Nanopartículas/química , alfa-Tocoferol/química , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Docetaxel , Resistencia a Antineoplásicos , Femenino , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Taxoides/química , Taxoides/farmacología , Difracción de Rayos X
9.
Yao Xue Xue Bao ; 50(2): 141-7, 2015 Feb.
Artículo en Zh | MEDLINE | ID: mdl-25975019

RESUMEN

Cell-penetrating peptides (CPPs) offer a non-selective and receptor-independent mode to promote cellular uptake. Although the non-specificity of CPP-mediated internalization allows this approach applicable to a wide range of tumor types potentially, their universality is a significant obstacle to their clinical utility for targeted delivery of cancer therapeutics and imaging agents. Accordingly, many reports have focused on selective switching of systemically delivered inert CPPs into their active form in lesions (tumor). In this review, our attention is mainly confined to such an enzyme-sensitive domain incorporated delivery system with activatable CPPs (ACPPs), which have displayed the exciting strength in balancing the CPPs' pros and cons, and potential in the treatment and diagnosis of some diseases.


Asunto(s)
Péptidos de Penetración Celular/química , Sistemas de Liberación de Medicamentos , Enzimas/química , Humanos , Neoplasias/tratamiento farmacológico
10.
Biomaterials ; 308: 122581, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38640783

RESUMEN

Cancer stem cells (CSCs) characterized by self-renewal, invasiveness, tumorigenicity and resistance to treatment are regarded as the thorniest issues in refractory tumors. We develop a targeted and hierarchical controlled release nano-therapeutic platform (SEED-NPs) that self-identifies and responds to CSC and non-CSC micro-niches of tumors. In non-CSC micro-niche, reactive oxygen species (ROS) trigger the burst release of the chemotherapeutic drug and photosensitizer to kill tumor cells and reduce tumor volume by combining chemotherapy and photodynamic therapy (PDT). In CSC micro-niche, the preferentially released differentiation drug induces CSC differentiation and transforms CSCs into chemotherapy-sensitive cells. SEED-NPs exhibit an extraordinary capacity for downregulating the stemness of CD44+/CD24- SP (side population) cell population both in vitro and in vivo, and reveal a 4-fold increase of tumor-targeted accumulation. Also, PDT-generated ROS promote the formation of tunneling nanotubes and facilitate the divergent network transport of drugs in deep tumors. Moreover, ROS in turn promotes CSC differentiation and drug release. This positive-feedback-loop strategy enhances the elimination of refractory CSCs. As a result, SEED-NPs achieve excellent therapeutic effects in both 4T1 SP tumor-bearing mice and regular 4T1 tumor-bearing mice without obvious toxicities and eradicate half of mice tumors. SEED-NPs integrate differentiation, chemotherapy and PDT, which proved feasible and valuable, indicating that active targeting and hierarchical release are necessary to enhance antitumor efficacy. These findings provide promising prospects for overcoming barriers in the treatment of CSCs.


Asunto(s)
Células Madre Neoplásicas , Fotoquimioterapia , Especies Reactivas de Oxígeno , Animales , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Fotoquimioterapia/métodos , Ratones , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Ratones Endogámicos BALB C , Femenino , Humanos , Fármacos Fotosensibilizantes/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Microambiente Tumoral/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos
11.
ACS Nano ; 18(9): 7267-7286, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38382065

RESUMEN

Cancer progression and treatment-associated cellular stress impairs therapeutic outcome by inducing resistance. Endoplasmic reticulum (ER) stress is responsible for core events. Aberrant activation of stress sensors and their downstream components to disrupt homeostasis have emerged as vital regulators of tumor progression as well as response to cancer therapy. Here, an orchestrated nanophotoinducer (ERsNP) results in specific tumor ER-homing, induces hyperthermia and mounting oxidative stress associated reactive oxygen species (ROS), and provokes intense and lethal ER stress upon near-infrared laser irradiation. The strengthened "dying" of ER stress and ROS subsequently induce apoptosis for both primary and abscopal B16F10 and GL261 tumors, and promote damage-associated molecular patterns to evoke stress-dependent immunogenic cell death effects and release "self-antigens". Thus, there is a cascade to activate maturation of dendritic cells, reprogram myeloid-derived suppressor cells to manipulate immunosuppression, and recruit cytotoxic T lymphocytes and effective antitumor response. The long-term protection against tumor recurrence is realized through cascaded combinatorial preoperative and postoperative photoimmunotherapy including the chemokine (C-C motif) receptor 2 antagonist, ERsNP upon laser irradiation, and an immune checkpoint inhibitor. The results highlight great promise of the orchestrated nanophotoinducer to exert potent immunogenic cell stress and death by reinforcing ER stress and oxidative stress to boost cancer photoimmunotherapy.


Asunto(s)
Neoplasias , Humanos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias/terapia , Estrés del Retículo Endoplásmico/efectos de la radiación , Estrés Oxidativo , Apoptosis , Línea Celular Tumoral
12.
Pharmaceutics ; 15(5)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37242692

RESUMEN

Gene therapy has emerged as a powerful tool to treat various diseases, such as cardiovascular diseases, neurological diseases, ocular diseases and cancer diseases. In 2018, the FDA approved Patisiran (the siRNA therapeutic) for treating amyloidosis. Compared with traditional drugs, gene therapy can directly correct the disease-related genes at the genetic level, which guarantees a sustained effect. However, nucleic acids are unstable in circulation and have short half-lives. They cannot pass through biological membranes due to their high molecular weight and massive negative charges. To facilitate the delivery of nucleic acids, it is crucial to develop a suitable delivery strategy. The rapid development of delivery systems has brought light to the gene delivery field, which can overcome multiple extracellular and intracellular barriers that prevent the efficient delivery of nucleic acids. Moreover, the emergence of stimuli-responsive delivery systems has made it possible to control the release of nucleic acids in an intelligent manner and to precisely guide the therapeutic nucleic acids to the target site. Considering the unique properties of stimuli-responsive delivery systems, various stimuli-responsive nanocarriers have been developed. For example, taking advantage of the physiological variations of a tumor (pH, redox and enzymes), various biostimuli- or endogenous stimuli-responsive delivery systems have been fabricated to control the gene delivery processes in an intelligent manner. In addition, other external stimuli, such as light, magnetic fields and ultrasound, have also been employed to construct stimuli-responsive nanocarriers. Nevertheless, most stimuli-responsive delivery systems are in the preclinical stage, and some critical issues remain to be solved for advancing the clinical translation of these nanocarriers, such as the unsatisfactory transfection efficiency, safety issues, complexity of manufacturing and off-target effects. The purpose of this review is to elaborate the principles of stimuli-responsive nanocarriers and to emphasize the most influential advances of stimuli-responsive gene delivery systems. Current challenges of their clinical translation and corresponding solutions will also be highlighted, which will accelerate the translation of stimuli-responsive nanocarriers and advance the development of gene therapy.

13.
Polymers (Basel) ; 15(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37177365

RESUMEN

Polymer-protein systems have excellent characteristics, such as non-toxic, non-irritating, good water solubility and biocompatibility, which makes them very appealing as cancer therapeutics agents. Inspiringly, they can achieve sustained release and targeted delivery of drugs, greatly improving the effect of cancer therapy and reducing side effects. However, many challenges, such as reducing the toxicity of materials, protecting the activities of proteins and controlling the release of proteins, still need to be overcome. In this review, the design of hybrid polymer-protein systems, including the selection of polymers and the bonding forms of polymer-protein systems, is presented. Meanwhile, vital considerations, including reaction conditions and the release of proteins in the design process, are addressed. Then, hybrid polymer-protein systems developed in the past decades for cancer therapy, including targeted therapy, gene therapy, phototherapy, immunotherapy and vaccine therapy, are summarized. Furthermore, challenges for the hybrid polymer-protein systems in cancer therapy are exemplified, and the perspectives of the field are covered.

14.
J Control Release ; 353: 423-433, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36470333

RESUMEN

Despite the promising potential of cancer vaccine, their efficacy has been limited in clinical trials and improved methods are urgently needed. Here we designed a nanovaccine platform that contains dendritic cell derived exosomes carriers and patient-specific neoantigens for individualized immunotherapies. The nanovaccine exhibited convenient cargo loading and prolonged cargo transportation to the lymph nodes, followed by eliciting potent antigen specific broad-spectrum T-cell and B-cell-mediated immune responses with great biosafety and biocompatibility. Strikingly, delivery of neoantigen-exosome nanovaccine significantly prohibited tumor growth, prolonged survival, delayed tumor occurrences with long-term memory, eliminated the lung metastasis in the therapeutic, prophylactic and metastatic B16F10 melanoma as well as therapeutic MC-38 models, respectively. Additionally, exosome-based nanovaccine demonstrated synergistic antitumor response superior to liposomal formulation due to presence of exosomal proteins. Collectively, our research indicated improved strategies for cell free vaccines and suggested exosome-based nanoplatform for cancer immunotherapy and personalized nanotechnology. These findings represent a powerful pathway to generate individualized nanovaccine rapidly for clinical application.


Asunto(s)
Vacunas contra el Cáncer , Exosomas , Melanoma , Neoplasias , Humanos , Células Dendríticas , Neoplasias/tratamiento farmacológico , Linfocitos T , Melanoma/metabolismo , Antígenos de Neoplasias , Inmunoterapia
15.
J Clin Med ; 11(15)2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35956236

RESUMEN

Background: Deep learning (DL) could predict isocitrate dehydrogenase (IDH) mutation status from MRIs. Yet, previous work focused on CNNs with refined tumor segmentation. To bridge the gap, this study aimed to evaluate the feasibility of developing a Transformer-based network to predict the IDH mutation status free of refined tumor segmentation. Methods: A total of 493 glioma patients were recruited from two independent institutions for model development (TCIA; N = 259) and external test (AHXZ; N = 234). IDH mutation status was predicted directly from T2 images with a Swin Transformer and conventional ResNet. Furthermore, to investigate the necessity of refined tumor segmentation, seven strategies for the model input image were explored: (i) whole tumor slice; (ii-iii) tumor mask and/or not edema; (iv-vii) tumor bounding box of 0.8, 1.0, 1.2, 1.5 times. Performance comparison was made among the networks of different architectures along with different image input strategies, using area under the curve (AUC) and accuracy (ACC). Finally, to further boost the performance, a hybrid model was built by incorporating the images with clinical features. Results: With the seven proposed input strategies, seven Swin Transformer models and seven ResNet models were built, respectively. Based on the seven Swin Transformer models, an averaged AUC of 0.965 (internal test) and 0.842 (external test) were achieved, outperforming 0.922 and 0.805 resulting from the seven ResNet models, respectively. When a bounding box of 1.0 times was used, Swin Transformer (AUC = 0.868, ACC = 80.7%), achieved the best results against the one that used tumor segmentation (Tumor + Edema, AUC = 0.862, ACC = 78.5%). The hybrid model that integrated age and location features into images yielded improved performance (AUC = 0.878, Accuracy = 82.0%) over the model that used images only. Conclusions: Swin Transformer outperforms the CNN-based ResNet in IDH prediction. Using bounding box input images benefits the DL networks in IDH prediction and makes the IDH prediction free of refined glioma segmentation feasible.

16.
Pharmaceutics ; 14(4)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35456600

RESUMEN

Hot melt extrusion (HME), a continuous manufacturing process for generating supersaturating amorphous self-micellizing solid dispersion systems (saSMSDs), holds promise for achieving amorphization of many pharmaceutical formulations. For saSMSDs generation, HME-triggered continuous processes offer advantages over traditional non-continuous processes such as fusion/quench cooling (FQC) and co-precipitation (CP). Here we employed HME, FQC, and CP to generate saSMSDs containing the water-insoluble BCS II drug nitrendipine (NIT) and self-micellizing polymer Soluplus®. Scanning electron microscopy, powder X-ray diffraction, and differential scanning calorimetry results revealed that saSMSDs formed when NIT-Soluplus® mixtures were subjected to the abovementioned amorphization methods. All saSMSDs outperformed crystalline NIT preparations and physical mixtures in achieving extended supersaturable immediate release states with superior solubility, "spring-parachute" process characteristics, and dissolution behaviors. Notably, Fourier transform-infrared spectroscopic results obtained for saSMSDs detected hydrogen bonding interactions between the drug and the carrier. Ultimately, our results revealed the advantages of HME-triggered amorphization as a continuous process for significantly improving drug dissolution, increasing solubility, and maintaining supersaturation as compared to traditional amorphization-based techniques.

17.
Polymers (Basel) ; 14(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36432925

RESUMEN

The short-term immediate release of supersaturated drug-delivery systems (SDDSs) presents an interesting process that can be tailored to multi-stage release events including initial release after dosing and dissolution, evolved release over longer dissolution periods for biological absorption, and terminal release following the end of immediate release. However, although comprehensive analysis of these critical release behaviors is often ignored yet essential for understanding the supersaturable immediate-release events for supersaturable solid formations when employing new techniques or polymers matched to a particular API. Hot-melt extrusion (HME) has become a popular continuous thermodynamic disordering technique for amorphization. The self-micellizing polymer Soluplus® is reported to be a potential amorphous and amphiphilic graft copolymer frequently used in many nano/micro supersaturable formulations. Our current work aims to develop hypotensive supersaturating solid dispersion systems (faSDDSHME) containing the BCS II drug, felodipine, when coordinately employing the HME technique and self-micellizing Soluplus®, and to characterize their amorphization as well as immediate release. Other discontinuous techniques were used to prepare control groups (faSDDSSE and faSDDSQC). Tailored initial/evolved/terminal three-stage supersaturable immediate-release behaviors were identified and possible mechanisms controlling the release were explored. HME produced the highest initial release in related faSDDSHME. During the evolved-release period, highly extended "spring-parachute" process was found in HME-induced amorphization owing to its superior supersaturation duration. Due to the enhanced crystallization inhibition effect, faSDDSHME displayed the strongest terminal release as measured by solubility. For release mechanisms associated with HME, molecular interaction is not the likely dominant mechanism responsible for the improved properties induced by faSDDSHME. For release mechanisms involved with the polymer Soluplus® itself, they were found to inhibit drug recrystallization, spontaneously solubilize the drug and lead to improved molecular interactions in all SDDS systems, which were the factors responsible for the improved release. These mechanisms play an important role for the generation of an extended multi-stage immediate release produced via HME or self-micellizing polymer. This study provides a deeper understanding on amorphization and superior multi-stage supersaturable immediate-release behaviors for a particular hypotensive supersaturated delivery system combined with an HME-based continuous manufacturing technique and self-micellizing polymer strategy.

18.
Insights Imaging ; 13(1): 184, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36471022

RESUMEN

OBJECTIVE: This study aimed to develop a deep learning (DL) model to improve the diagnostic performance of EIC and ASPECTS in acute ischemic stroke (AIS). METHODS: Acute ischemic stroke patients were retrospectively enrolled from 5 hospitals. We proposed a deep learning model to simultaneously segment the infarct and estimate ASPECTS automatically using baseline CT. The model performance of segmentation and ASPECTS scoring was evaluated using dice similarity coefficient (DSC) and ROC, respectively. Four raters participated in the multi-reader and multicenter (MRMC) experiment to fulfill the region-based ASPECTS reading under the assistance of the model or not. At last, sensitivity, specificity, interpretation time and interrater agreement were used to evaluate the raters' reading performance. RESULTS: In total, 1391 patients were enrolled for model development and 85 patients for external validation with onset to CT scanning time of 176.4 ± 93.6 min and NIHSS of 5 (IQR 2-10). The model achieved a DSC of 0.600 and 0.762 and an AUC of 0.876 (CI 0.846-0.907) and 0.729 (CI 0.679-0.779), in the internal and external validation set, respectively. The assistance of the DL model improved the raters' average sensitivities and specificities from 0.254 (CI 0.22-0.26) and 0.896 (CI 0.884-0.907), to 0.333 (CI 0.301-0.345) and 0.915 (CI 0.904-0.926), respectively. The average interpretation time of the raters was reduced from 219.0 to 175.7 s (p = 0.035). Meanwhile, the interrater agreement increased from 0.741 to 0.980. CONCLUSIONS: With the assistance of our proposed DL model, radiologists got better performance in the detection of AIS lesions on NCCT.

19.
Yao Xue Xue Bao ; 46(7): 859-63, 2011 Jul.
Artículo en Zh | MEDLINE | ID: mdl-22010358

RESUMEN

To prepare rivastigmine liposome, rivastigmine was loaded into liposome via ammonium sulfate gradient method. Its pharmacokinetic profile in rats was evaluated after intranasal administration. The size, zeta potential, entrapped efficiency and release of rivastigmine from the liposome in vitro were determined. Plasma concentration of rivastigmine was determined by high performance liquid chromatography-tandem mass spectrometry (HPLC/MS) using antipyrine as internal standard. The pharmacokinetic parameters were calculated by DAS 2.0. The entrapped efficiency of rivastigmine liposome was (33.41 +/- 6.58) %, with the mean diameter of 154-236 nm and zeta potential of (-10.47 +/- 2.41) mV. The release behavior of rivastigmine was fitting the first order equation in vitro. The pharmacokinetic studies indicated that the C(max), T(max) and AUC(0-infinity), of rivastigmine liposome were (1.50 +/- 0.15) mg x L(-1), 15 min and (89.06 +/- 8.30) mg x L(-') x min, respectively. Rivastimine liposome was absorbed rapidly, and could reach a certain concentration in rat plasma after intranasal delivery.


Asunto(s)
Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/farmacocinética , Fenilcarbamatos/administración & dosificación , Fenilcarbamatos/farmacocinética , Administración Intranasal , Animales , Área Bajo la Curva , Cromatografía Liquida , Portadores de Fármacos , Composición de Medicamentos , Liposomas , Masculino , Fármacos Neuroprotectores/sangre , Fármacos Neuroprotectores/química , Tamaño de la Partícula , Fenilcarbamatos/sangre , Fenilcarbamatos/química , Ratas , Ratas Sprague-Dawley , Rivastigmina , Espectrometría de Masas en Tándem
20.
Biomaterials ; 269: 120648, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33445099

RESUMEN

Phototherapy and immunogenic cell death (ICD) are powerful strategies to fight cancer. However, their therapeutic outcomes are diminished by immunosuppressive and hypoxia microenvironment. Herein, a photo-based, immunomodulating and hypoxia-alleviated nanosystem, PDA-ICG@CAT-DTA-1, is proposed to achieve the synergism between phototherapy and immunotherapy. Catalase (CAT) and anti-GITR antibody (DTA-1) are loaded to photothermal agent and photosensitizer composed PDA-ICG nanoparticles. The PDA-ICG@CAT-DTA-1 exhibits intrinsic local hyperthermia and enhanced ROS generation in tumor, and abrogates tumor immune suppression. It results in reduction of intratumoral FOXP3+ regulatory T cells (4.3-fold) and increase of CD4+ effector T cells (1.5-fold) compare with the control, and promotes damage associated molecular patterns generation to reinvigorate ICD effect. The potent antitumor of PDA-ICG@CAT-DTA-1 is proved in 4T1 bilateral tumor-bearing mice, with inhibition ratio of 95.1% for primary cancers and 68.7% for abscopal cancers. Our findings highlight great promise of the constructed versatility nanosystem to fix bottlenecks for cancer therapy.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Neoplasias , Animales , Línea Celular Tumoral , Muerte Celular Inmunogénica , Inmunoterapia , Ratones , Neoplasias/tratamiento farmacológico , Fototerapia
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