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1.
Int J Pharm ; 664: 124636, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39197798

RESUMO

Protein therapeutics, particularly antibodies, depend on maintaining their native structures for optimal function. Hydrophobic interfaces, such as the air-water interface, can trigger protein aggregation and denaturation. While completely avoiding such interfacial exposures during manufacturing and storage is impractical, minimizing them is crucial for enhancing protein drug stability and extending shelf life. In the biologics industry, surfactants like polysorbates are commonly used as additives (excipients) to mitigate these undesirable interfacial exposures. However, polysorbates, the most prevalent choice, have recognized limitations in terms of polydispersity, purity, and stability, prompting the exploration of alternative excipients. The present study identifies poly(N-isopropylacrylamide)-poly(ethylene glycol) (PNIPAM-PEG) block copolymers as a promising alternative to polysorbates. Due to its stronger affinity for the air-water interface, PNIPAM-PEG significantly outperforms polysorbates in enhancing protein stability. This claim is supported by results from multiple tests. Accelerated dynamic light scattering (DLS) experiments demonstrate PNIPAM-PEG's exceptional efficacy in preserving IgG stability against surface-induced aggregation, surpassing conventional polysorbate excipients (Tween 80 and Tween 20) under high-temperature conditions. Additionally, circular dichroism (CD) spectroscopy results reveal conformational alterations associated with aggregation, with PNIPAM-PEG consistently demonstrates a greater protective effect by mitigating negative shifts at λ â‰… 220 nm, indicative of changes in secondary structure. Overall, this study positions PNIPAM-PEG as a promising excipient for antibody therapeutics, facilitating the development of more stable and effective biopharmaceuticals.


Assuntos
Resinas Acrílicas , Excipientes , Polietilenoglicóis , Estabilidade Proteica , Polietilenoglicóis/química , Excipientes/química , Resinas Acrílicas/química , Estabilidade de Medicamentos , Produtos Biológicos/química , Imunoglobulina G/química , Polissorbatos/química , Agregados Proteicos
2.
Artigo em Inglês | MEDLINE | ID: mdl-37632203

RESUMO

Rare but consistent reports of abscopal remission in patients challenge the notion that radiotherapy (RT) is a local treatment; radiation-induced cancer cell death can trigger activation and recruitment of dendritic cells to the primary tumor site, which subsequently initiates systemic immune responses against metastatic lesions. Although this abscopal effect was initially considered an anomaly, combining RT with immune checkpoint inhibitor therapies has been shown to greatly improve the incidence of abscopal responses via modulation of the immunosuppressive tumor microenvironment. Preclinical studies have demonstrated that nanomaterials can further improve the reliability and potency of the abscopal effect for various different types of cancer by (1) altering the cell death process to be more immunogenic, (2) facilitating the capture and transfer of tumor antigens from the site of cancer cell death to antigen-presenting cells, and (3) co-delivering immune checkpoint inhibitors along with radio-enhancing agents. Several unanswered questions remain concerning the exact mechanisms of action for nanomaterial-enhanced RT and for its combination with immune checkpoint inhibition and other immunostimulatory treatments in clinically relevant settings. The purpose of this article is to summarize key recent developments in this field and also highlight knowledge gaps that exist in this field. An improved mechanistic understanding will be critical for clinical translation of nanomaterials for advanced radio-immunotherapy. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Reprodutibilidade dos Testes , Imunoterapia , Neoplasias/radioterapia , Nanotecnologia , Nanoestruturas/uso terapêutico , Microambiente Tumoral
3.
Biomater Sci ; 11(18): 6311-6324, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37552121

RESUMO

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) prodrug is a clinically tried and proven treatment modality for surface-level lesions. However, its use for deep-seated tumors has been limited due to the poor penetration depth of visible light needed to activate the photosensitizer protoporphyrin IX (PPIX), which is produced from ALA metabolism. Herein, we report the usage of poly(ethylene glycol-b-lactic acid) (PEG-PLA)-encapsulated calcium tungstate (CaWO4, CWO for short) nanoparticles (PEG-PLA/CWO NPs) as energy transducers for X-ray-activated PDT using ALA. Owing to the spectral overlap between radioluminescence afforded by the CWO core and the absorbance of PPIX, these NPs can serve as an in situ visible light activation source during radiotherapy (RT), thereby mitigating the limitation of penetration depth. We demonstrate that this effect is observed across different cell lines with varying radio-sensitivity. Importantly, both PPIX and PEG-PLA/CWO NPs exhibit no significant toxicities at therapeutic doses in the absence of radiation. To assess the efficacy of this approach, we conducted a study using a syngeneic mouse model subcutaneously implanted with inherently radio-resistant 4T1 tumors. The results show a significantly improved prognosis compared to conventional RT, even with as few as 2 fractions of 4 Gy X-rays. Taken together, these results suggest that PEG-PLA/CWO NPs are promising agents for application of ALA-PDT in deep-seated tumors, thereby significantly expanding the utility of the already established treatment strategy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Pró-Fármacos , Animais , Camundongos , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
4.
J Cerebrovasc Endovasc Neurosurg ; 25(2): 203-207, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36266782

RESUMO

A giant thrombosed extracranial internal carotid artery aneurysm (ECCA) is extremely rare and its treatment is challenging. Despite the advance of endovascular technique, open surgery is still considered a first-line treatment in giant thrombosed ECCA. We describe a case of giant thrombosed ECCA which was successfully treated by aneurysmectomy and graft interposition with the technical details.

5.
Front Microbiol ; 12: 737031, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867853

RESUMO

3C protease (3Cpro), a chymotrypsin-like cysteine protease encoded by the foot-and-mouth disease virus (FMDV), plays an essential role in processing the FMDV P1 polyprotein into individual viral capsid proteins in FMDV replication. Previously, it has been shown that 3Cpro is involved in the blockage of the host type-I interferon (IFN) responses by FMDV. However, the underlying mechanisms are poorly understood. Here, we demonstrated that the protease activity of 3Cpro contributed to the degradation of RIG-I and MDA5, key cytosolic sensors of the type-I IFN signaling cascade in proteasome, lysosome and caspase-independent manner. And also, we examined the degradation ability on RIG-I and MDA5 of wild-type FMDV 3Cpro and FMDV 3Cpro C142T mutant which is known to significantly alter the enzymatic activity of 3Cpro. The results showed that the FMDV 3Cpro C142T mutant dramatically reduce the degradation of RIG-I and MDA5 due to weakened protease activity. Thus, the protease activity of FMDV 3Cpro governs its RIG-I and MDA5 degradation ability and subsequent negative regulation of the type-I IFN signaling. Importantly, FMD viruses harboring 3Cpro C142T mutant showed the moderate attenuation of FMDV in a pig model. In conclusion, our results indicate that a novel mechanism evolved by FMDV 3Cpro to counteract host type-I IFN responses and a rational approach to virus attenuation that could be utilized for future vaccine development.

6.
J Med Food ; 23(4): 459-464, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32109191

RESUMO

This study was to compare the anticolitis activity of fresh Saengshik (FSS) with heated Saengshik (HSS) with dextran sulfate sodium (DSS)-induced experimental colitis mouse model. Both FSS- and HSS-fed colitis mice exhibited the effects of the increase in the body weight, the alleviation in the colon shortening, and the reduction of the ratio of colon weight to length. However, FSS-fed colitis mice showed a much more significant decrease in DSS-induced tissue damage by mucosal edema and crypt deficiency than did HSS-fed ones. Besides, FSS contributed to decreasing the serum levels of proinflammatory cytokines (tumor necrosis factor-alpha and interleukin-1 beta) and inhibiting the colonic mRNA expressions of these cytokines in colitis tissue of the mice. FSS also resulted in the lower colonic mRNA expression level of inflammation-related inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in colitis mice than did HSS. Overall results confirmed Saengshik, especially FSS, inhibits more effectively against DSS-induced inflammation reaction in colitis mice than HSS.


Assuntos
Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Colite/induzido quimicamente , Colite/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Animais , Peso Corporal , Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , República da Coreia , Fator de Necrose Tumoral alfa/metabolismo
7.
Maxillofac Plast Reconstr Surg ; 40(1): 36, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30538972

RESUMO

BACKGROUND: Botulinum toxin-A (BTX-A) injection into muscle reduces muscular power and may prevent post-operative complication after orthognathic surgery. The purpose of this study was (1) to evaluate BTX-A injection into the masseter muscle on the prevention of plate fracture and (2) to compare post-operative relapse between the BTX-A injection group and the no injection group. METHODS: Sixteen patients were included in this study. Eight patients received BTX-A injection bilaterally, and eight patients served as control. All patients received bilateral sagittal split ramus osteotomy for the mandibular setback and additional surgery, such as LeFort I osteotomy or genioplasty. Post-operative plate fracture was recorded. SNB angle, mandibular plane angle, and gonial angle were used for post-operative relapse. RESULTS: Total number of fractured plates in patients was 2 out of 16 plates in the BTX-A injection group and that was 8 out of 16 plates in the no treatment group (P = 0.031). However, there were no significant differences in post-operative changes in SNB angle, mandibular plane angle, and gonial angle between groups (P > 0.05). CONCLUSIONS: BTX-A injection into the masseter muscle could reduce the incidence of plate fracture.

8.
J Korean Assoc Oral Maxillofac Surg ; 44(1): 29-33, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29535967

RESUMO

Sinonasal mucosal melanoma (SNMM) in the maxillary sinus is a rare disease condition. Compared to oral mucosal melanoma, SNMM has a bulky, exophytic, and polypoid appearance, is weakly pigmented, and associated with unspecific symptoms. Due to these features, SNMM in the maxillary sinus has been misdiagnosed as nasal polyps and chronic sinusitis. In this case report, we described SNMM occurring in the right maxillary sinus simulated as a cystic or benign lesion. Cortical bone thinning and expansion were observed around the mass. The excised soft mass was encapsulated and weakly pigmented. The mass was clearly excised and covered with a pedicled buccal fat pad graft. Diagnosis using immunohistochemistry with S-100 and homatropine methylbromide-45 (HMB-45) is critical for proper treatment.

9.
J Craniofac Surg ; 29(2): 415-419, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29215451

RESUMO

A patient had a right mandibular defect due to resection of an ameloblastoma. Previously, the defect had been reconstructed by an iliac bone graft, and subsequently, a titanium mesh with xenograft was used. However, it was not successfully reconstructed. For the recovery of mandible continuity and rehabilitation of jaw movement, we manufactured a customized 3-dimensional titanium implant by computer-aided design and manufacturing and electron beam melting technology. This implant was designed to have a porous body structure and lingual plate. The customized implant was accurately inserted in the bony defect. As a result, the patient showed a normal range of mouth opening and jaw movement. New bone migration was observed in the porous structure of the implant. Although there was a slight plate exposure and lack of alveolar bone formation, the customized 3D titanium implant successfully reconstructed the mandibular discontinuous defect and recovered jaw movement.


Assuntos
Mandíbula/cirurgia , Reconstrução Mandibular , Próteses e Implantes , Titânio/uso terapêutico , Desenho Assistido por Computador , Humanos , Imageamento Tridimensional , Reconstrução Mandibular/instrumentação , Reconstrução Mandibular/métodos , Amplitude de Movimento Articular
10.
J Med Food ; 20(12): 1214-1221, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29243969

RESUMO

Oligonol, a polyphenol derived from lychee fruit, is produced by an oligomerization process that converts high-molecular-weight polyphenol polymers into low-molecular-weight oligomers. Evidence suggests that oligonol exerts its beneficial effects based on antioxidant and anti-inflammatory properties. This study was the first to investigate the antioxidative and anti-inflammatory effects of oligonol on gastroesophageal inflammatory models: surgically induced acute reflux esophagitis (RE) and gastric ulcer (GU) induced by HCl/ethanol. In the in vitro study, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) radical scavenging assays were performed to determine the antioxidant activity of oligonol. The experimental groups were each composed of normal, vehicle, and oligonol groups. RE rats and GU mice were treated orally with oligonol (100 mg/kg bw) or distilled water as a vehicle (n = 8 for each group). Oligonol exhibited potent free radical-scavenging capacities for DPPH and ABTS radicals, activities that were similar to those of ascorbic acid. The in vivo study revealed that oligonol consumption significantly prevented RE and GU formation and decreased the gross mucosal injury from oxidative stress. Oligonol decreased the reactive oxygen species levels and elevated levels of both inflammatory mediators and cytokines (p-IκB, NF-κBp65, COX-2, iNOS, TNF-α, and IL-1ß) in the RE and GU models. Oligonol had a protective effect against oxidative stress by regulating antioxidant enzyme (superoxide dismutase, catalase, and GPx-1/2) activities in GU mice. Oligonol has potential as a preventive and therapeutic agent for gastroesophageal inflammatory diseases, including RE and GU.


Assuntos
Catequina/análogos & derivados , Esofagite Péptica/tratamento farmacológico , Litchi/química , Fenóis/administração & dosagem , Extratos Vegetais/administração & dosagem , Úlcera Gástrica/tratamento farmacológico , Animais , Antioxidantes/administração & dosagem , Catequina/administração & dosagem , Catequina/química , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Esofagite Péptica/genética , Esofagite Péptica/metabolismo , Etanol/efeitos adversos , Frutas/química , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos , Fenóis/química , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/genética , Úlcera Gástrica/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
Food Funct ; 7(7): 3056-3063, 2016 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-27248500

RESUMO

We have identified the effects of oligonol, a low-molecular polyphenol derived from lychee fruit, on diabetes-induced pancreatic damage via oxidative stress. Oligonol was orally administered at 10 or 20 mg (kg d)(-1) for 10 days to streptozotocin (STZ)-induced diabetic rats, and we assessed the changes in the serum glucose and insulin levels, as well as those of body weight and food and water consumption. In addition, analyses of the weight, insulin content, reactive oxygen species (ROS) level, and western blots of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-4 (Nox-4), p22(phox), p47(phox), phosphor-c-Jun N-terminal kinase (p-JNK), Bax, cytochrome c, caspase 3, pancreatic-duodenal homeobox (PDX-1) and cyclin E were also performed in the pancreas. However, these unfavorable outcomes under diabetes were reversed by oligonol administration. Oligonol treatment led to significantly attenuated histological damage in the pancreas. In conclusion, this study suggests that oligonol protects the pancreas from Bax and PDX-1 via oxidative stress for the prevention or delaying of diabetes mellitus.


Assuntos
Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Litchi/química , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Fenóis/farmacologia , Animais , Glicemia/metabolismo , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Frutas/química , Regulação da Expressão Gênica , Insulina/sangue , Masculino , Peso Molecular , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Pâncreas/citologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
12.
Nanomaterials (Basel) ; 6(10)2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-28335313

RESUMO

Palladium (Pd)-based hydrogen (H2) gas sensors have been widely investigated thanks to its fast reaction and high sensitivity to hydrogen. Various sensing mechanisms have been adopted for H2 gas sensors; however, all the sensors must be powered through an external battery. We report here an H2 gas sensor that can detect H2 by measuring the output voltages generated during contact electrification between two friction surfaces. When the H2 sensor, composed of Pd-coated ITO (indium tin oxide) and PET (polyethylene Terephthalate) film, is exposed to H2, its output voltage is varied in proportion to H2 concentration because the work function (WF) of Pd-coated surface changes, altering triboelectric charging behavior. Specifically, the output voltage of the sensor is gradually increased as exposing H2 concentration increases. Reproducible and sensitive sensor response was observed up 1% H2 exposure. The approach introduced here can easily be adopted to development of triboelectric gas sensors detecting other gas species.

13.
Nutr Res Pract ; 9(6): 619-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26634051

RESUMO

BACKGROUND/OBJECTIVES: Colitis is a serious health problem, and chronic obesity is associated with the progression of colitis. The aim of this study was to determine the effects of natural raw meal (NRM) on high-fat diet (HFD, 45%) and dextran sulfate sodium (DSS, 2% w/v)-induced colitis in C57BL/6J mice. MATERIALS/METHODS: Body weight, colon length, and colon weight-to-length ratio, were measured directly. Serum levels of obesity-related biomarkers, triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), insulin, leptin, and adiponectin were determined using commercial kits. Serum levels of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 were detected using a commercial ELISA kit. Histological study was performed using a hematoxylin and eosin (H&E) staining assay. Colonic mRNA expressions of TNF-α, IL-1ß, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR assay. RESULTS: Body weight and obesity-related biomarkers (TG, TC, LDL, HDL, insulin, leptin, and adiponectin) were regulated and obesity was prevented in NRM treated mice. NRM significantly suppressed colon shortening and reduced colon weight-to-length ratio in HFD+DSS induced colitis in C57BL/6J mice (P < 0.05). Histological observations suggested that NRM reduced edema, mucosal damage, and the loss of crypts induced by HFD and DSS. In addition, NRM decreased the serum levels of pro-inflammatory cytokines, TNF-α, IL-1ß, and IL-6 and inhibited the mRNA expressions of these cytokines, and iNOS and COX-2 in colon mucosa (P < 0.05). CONCLUSION: The results suggest that NRM has an anti-inflammatory effect against HFD and DSS-induced colitis in mice, and that these effects are due to the amelioration of HFD and/or DSS-induced inflammatory reactions.

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