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1.
J Nanobiotechnology ; 19(1): 198, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34217325

RESUMO

BACKGROUND: The postoperative recurrence of malignant gliomas has presented a clinical conundrum currently. Worse, there is no standard treatment for these recurrent tumours. Therefore, novel promising methods of clinical treatment are urgently needed. METHODS: In this study, we synthesized reactive oxygen species (ROS)-triggered poly(propylene sulfide)60 (PPS60) mixed with matrix metalloproteinases (MMPs)-responsive triglycerol monostearate (T) lipids and TMZ. The mixed solution could self-assemble at 50 â„ƒ to generate hydrogels with MMPs- and ROS-responsiveness. We explored whether the T/PPS + TMZ hydrogel could achieve the MMP- and ROS-responsive delivery of TMZ and exert anti-glioma regrowth effects in vitro and in vivo. These results demonstrated that the T/PPS + TMZ hydrogel significantly improved the curative effect of TMZ to inhibit postsurgical recurrent glioma. RESULTS: The results confirmed the responsive release of TMZ encapsulated in the T/PPS + TMZ hydrogel, and the hydrogel showed excellent performance against glioma in an incomplete glioma operation model, which indicated that the T/PPS + TMZ hydrogel effectively inhibited the growth of recurrent glioma. CONCLUSION: In summary, we successfully developed injectable MMPs- and ROS-responsive hydrogels that could achieve the sustained release of TMZ in the surgical cavity to inhibit local recurrent glioma after surgery.


Assuntos
Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Hidrogéis/química , Nanofibras/química , Recidiva Local de Neoplasia/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Espécies Reativas de Oxigênio
2.
J Wound Ostomy Continence Nurs ; 45(4): 310-318, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29889718

RESUMO

PURPOSE: The purpose of this study was to determine the effectiveness of a novel, noninvasive perfusion enhancement system versus beds with integrated alternating pressure capabilities for the prevention of hospital-acquired sacral region (sacral, coccygeal, and ischium) pressure injuries in a high-risk, acute care patient population. DESIGN: A prospective randomized trial of high-risk inpatients without preexisting sacral region pressure injuries was conducted. SUBJECTS AND SETTING: The sample comprised 431 randomly enrolled adult patients in a 300-bed tertiary care community teaching hospital. METHODS: Subjects were randomly allocated to one of 2 groups: control and experimental. Both groups received "standard-of-care" pressure injury prevention measures per hospital policy, and both were placed on alternating pressure beds during their hospital stays. In addition, patients in the experimental group used a noninvasive perfusion enhancement system placed on top of their alternating pressure beds and recovery chairs throughout their hospital stay. Fischer's exact probability test was used to compare group differences, and odds ratio (OR) were calculated for comparing pressure injury rates in the experimental and control groups. RESULTS: Three hundred ninety-nine patients completed the trial; 186 patients were allocated to the experimental group and 213 patients to the control group. Eleven patients in the control group versus 2 in the experimental group developed hospital-acquired sacral region pressure injuries (51.6% vs 1.07%; P = .024). Control patients were 5.04 times more likely to develop hospital-acquired sacral region pressure injuries (OR = 0.1996; 95% CI, 0.0437-0.9125). CONCLUSIONS: Patients using a noninvasive perfusion enhancement system developed significantly fewer hospital-acquired sacral pressure injuries than those using an alternating pressure bed without the perfusion enhancement system. These findings suggest that a perfusion enhancement system enhances the success of use of pressure redistributing beds for prevention of hospital-acquired sacral pressure injuries.


Assuntos
Reembasadores de Dentadura/normas , Perfusão/instrumentação , Perfusão/métodos , Úlcera por Pressão/terapia , Idoso , Leitos/normas , Feminino , Humanos , Doença Iatrogênica , Masculino , Pessoa de Meia-Idade , Perfusão/normas , Estudos Prospectivos , Fatores de Risco , Região Sacrococcígea/irrigação sanguínea , Região Sacrococcígea/lesões
3.
Pak J Pharm Sci ; 27(3 Suppl): 723-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24816703

RESUMO

The separation characteristics of Eucalyptus camaldulensis biomass cell wall were investigated and analyzed by FTIR, UV and XRD. The result showed that the crystallinity of untreated sample were lower than ones of treated samples at 10° C, 20° C and 30° C. Effect of temperature was very notable so as to use the lower temperature if cellulose would be kept natural structure during lignin separation from lignincellulose. Treatment time and temperature had a notably significant effect on SLR of E. camaldulensis lignin cellulose, and the SLR increased gradually with the temperature increment, and SLR were 73.35% at 10° C, 80.14% at 20° C, 83.73% at 30° C. The maximum of SLR increased with the rising of temperature 10° C, 20° C and 30° C. Consequently, the best separation conditions of lignin were 24h and 30° C. During hemicelluloses separation, the peak of C=O disappeared, and the peak of CO-OR, O-H and C-O abated, resulting that acetyl in hemicelluloses were mainly broken by the dehydration, heat decomposition reaction and mild thermal degradation. During lignin separation, the side chain and benzene ring of lignin of E. urophynis lignin cellulose reached the largest bond breaking characteristics under the temperature of 10° C at 7h, 20° C at 7h and 30° C at 24h.


Assuntos
Eucalyptus/química , Lignina/química , Celulose/química , Cristalização , Lignina/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
4.
Adv Mater ; 36(29): e2400502, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38651254

RESUMO

Chemotherapy of glioblastoma (GBM) has not yielded success due to inefficient blood-brain barrier (BBB) penetration and poor glioma tissue accumulation. Aerobic glycolysis, as the main mode of energy supply for GBM, safeguards the rapid growth of GBM while affecting the efficacy of radiotherapy and chemotherapy. Therefore, to effectively inhibit aerobic glycolysis, increase drug delivery efficiency and sensitivity, a novel temozolomide (TMZ) nanocapsule (ApoE-MT/siPKM2 NC) is successfully designed and prepared for the combined delivery of pyruvate kinase M2 siRNA (siPKM2) and TMZ. This drug delivery platform uses siPKM2 as the inner core and methacrylate-TMZ (MT) as the shell component to achieve inhibition of glioma energy metabolism while enhancing the killing effect of TMZ. By modifying apolipoprotein E (ApoE), dual targeting of the BBB and GBM is achieved in a "two birds with one stone" style. The glutathione (GSH) responsive crosslinker containing disulfide bonds ensures "directional blasting" cleavage of the nanocapsules to release MT and siPKM2 in the high GSH environment of glioma cells. In addition, in vivo experiments verify that ApoE-MT/siPKM2 NC has good targeting ability and prolongs the survival of tumor-bearing nude mice. In summary, this drug delivery system provides a new strategy for metabolic therapy sensitization chemotherapy.


Assuntos
Glioblastoma , Glicólise , Nanocápsulas , Temozolomida , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Animais , Temozolomida/farmacologia , Temozolomida/química , Nanocápsulas/química , Camundongos , Linhagem Celular Tumoral , Glicólise/efeitos dos fármacos , Humanos , Camundongos Nus , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , RNA Interferente Pequeno/metabolismo , Barreira Hematoencefálica/metabolismo , Glutationa/metabolismo , Glutationa/química
5.
Macromol Biosci ; : e2400050, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38810210

RESUMO

Traumatic brain injury (TBI) is the primary cause of child mortality and disability worldwide. It can result in severe complications that significantly impact children's quality of life, including post-traumatic epilepsy (PTE). An increasing number of studies suggest that TBI-induced oxidative stress and neuroinflammatory sequelae (especially, inflammation in the hippocampus region) may lead to the development of PTE. Due to the blood-brain barrier (BBB), typical systemic pharmacological therapy for TBI cannot deliver berberine (BBR) to the targeted location in the early stages of the injury, although BBR has strong anti-inflammatory properties. To break through this limitation, a microenvironment-responsive gelatin methacrylate (GM) hydrogel to deliver poly(propylene sulfide)60 (PPS60) and BBR (GM/PB) is developed for regulating neuroinflammatory reactions and removing reactive oxygen species (ROS) in the brain trauma microenvironment through PPS60. In situ injection of the GM/PB hydrogel efficiently bypasses the BBB and is administered directly to the surface of brain tissue. In post-traumatic brain injury models, GM/PB has the potential to mitigate oxidative stress and neuroinflammatory responses, facilitate functional recovery, and lessen seizing. These findings can lead to a new treatment for brain injuries, which minimizes complications and improves the quality of life.

6.
ACS Appl Mater Interfaces ; 15(8): 10356-10370, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36787514

RESUMO

Aerobic glycolysis is the primary energy supply mode for glioblastoma (GBM) cells to maintain growth and proliferation. However, due to the metabolic reprogramming of tumor cells, GBM can still produce energy through fatty acid oxidation (FAO) and amino acid metabolism after blocking this metabolic pathway. In addition, GBM can provide a steady stream of nutrients through high-density neovascularization, which puts the block energy metabolism therapy for glioma in the situation of "internal and external problems". Herein, based on the abundant reactive oxygen species (ROS) and glutathione (GSH) in the tumor microenvironment and cytoplasm, we successfully designed and developed a cascade-responsive 2-DG nanocapsule delivery system. This nanocapsule contains a conjugate of anti-VEGFR2 monoclonal antibody (aV) and CPT1C siRNA (siCPT1C) linked by a disulfide cross-linker (aV-siCPT1C). The surface of this nanocapsule (2-DG/aV-siCPT1C NC) is loaded with the glycolysis inhibitor 2-DG, and it utilizes GLUT1, which is highly expressed on the blood-brain barrier (BBB) and GBM cells, to effectively penetrate the BBB and target GBM. The nanocapsule realizes multidrug codelivery, jointly blocks glycolysis and FAO of GBM, and reduces angiogenesis. Meanwhile, it also solves the problems of low delivery efficiency of mAb in the central nervous system (CNS) and easy degradation of siRNA. In general, this drug joint delivery strategy could open up a new avenue for the treatment of GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanocápsulas , Humanos , Glioblastoma/tratamento farmacológico , Nanocápsulas/uso terapêutico , Linhagem Celular Tumoral , Metabolismo Energético , RNA Interferente Pequeno/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Microambiente Tumoral
7.
Drug Deliv ; 30(1): 1-13, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36579448

RESUMO

Temozolomide (TMZ) is a conventional chemotherapeutic drug for glioma, however, its clinical application and efficacy is severely restricted by its drug resistance properties. O6-methylguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme, which can repair the DNA damage caused by TMZ. A large number of clinical data show that reducing the expression of MGMT can enhance the chemotherapeutic efficacy of TMZ. Therefore, in order to improve the resistance of glioma to TMZ, an angiopep-2 (A2) modified nanoprodrug of polytemozolomide (P(TMZ)n) that combines with MGMT siRNA (siMGMT) targeting MGMT was developed (A2/T/D/siMGMT). It not only increased the amount of TMZ within tumor lesion site, but also reduced MGMT expression in glioma. The in vitro experiments indicated that the A2/T/D/siMGMT effectively enhanced the cellular uptake of TMZ and siMGMT, and resulted in a significant cell apoptosis and cytotoxicity in the glioma cells. The in vivo experiments showed that glioma growth was inhibited and the survival time of animals were prolonged remarkably after A2/T/D/siMGMT was injected via tail vein. The results showed that the therapeutic effect of A2/T/D/siMGMT in the treatment of glioma was significantly improved.


Assuntos
Neoplasias Encefálicas , Glioma , Animais , Temozolomida/farmacologia , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , RNA Interferente Pequeno/farmacologia , Linhagem Celular Tumoral , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , O(6)-Metilguanina-DNA Metiltransferase/genética , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , O(6)-Metilguanina-DNA Metiltransferase/farmacologia , Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética
8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): o2329, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058954

RESUMO

In the title compound, C(16)H(12)BrNO(3), the butyrolactone core adopts the furan-2(5H)-one structure and forms dihedral angles of 44.80 (17) and 65.73 (18)° with the bromo-benzene and phenol rings, respectively. In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules, generating R(4) (3)(26) loops The edge-fused rings extend to form a chain running along the b-axis direction and C-H⋯π contacts help to consolidate the packing.

9.
Biomater Sci ; 9(4): 1466, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33570070

RESUMO

Correction for 'Injectable postoperative enzyme-responsive hydrogels for reversing temozolomide resistance and reducing local recurrence after glioma operation' by Zongren Zhao et al., Biomater. Sci., 2020, 8, 5306-5316, DOI: 10.1039/D0BM00338G.

10.
Biomater Sci ; 8(15): 4370, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32638709

RESUMO

Correction for 'Injectable postoperative enzyme-responsive hydrogels for reversing temozolomide resistance and reducing local recurrence after glioma operation' by Zongren Zhao et al., Biomater. Sci., 2020, DOI: .

11.
Onco Targets Ther ; 13: 11397-11409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192073

RESUMO

BACKGROUND: Postoperative recurrence is the main reason for poor clinical outcomes in glioma patients, so preventing tumor recurrence is crucial in the management of gliomas. METHODS: In this study, the expression of matrix metalloproteinases (MMPs) in normal tissues was detected via RNA-seq analysis. Glioma cases from the public databases (The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA)) were included in this study. The hydrogel contains minocycline (Mino) and vorinostat (Vor) (G/Mino+Vor) was formed under 365 nm when the photoinitiator was added. High-performance liquid chromatography (HPLC) was used to assess the release of drugs in the G/Mino+Vor hydrogel. An MTT assay was used to explore the biosecurity of GelMA. Immunohistochemistry, ELISA, and TUNEL assays were used to demonstrate the antitumor effect of the G/Mino+Vor hydrogel. RESULTS: We successfully developed a G/Mino+Vor hydrogel. The experiments in vitro and in vivo confirmed the MMPs-responsive delivery of minocycline and vorinostat in hydrogel and the anti-glioma effect on an incomplete tumor operation model, which indicated that the G/Mino+Vor hydrogel effectively inhibited the recurrence of glioma after surgery. CONCLUSION: In summary, the G/Mino+Vor hydrogel could continuously release drugs and improve the therapy effects against recurrent glioma.

12.
Biomater Sci ; 8(19): 5306-5316, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32573615

RESUMO

Glioma is the most aggressive primary malignant brain tumor. The eradication of the gliomas by performing neurosurgery has not been successful due to the diffuse nature of malignant gliomas. Temozolomide (TMZ) is the first-line agent in treating gliomas after surgery, and its therapeutic efficacy is limited mainly due to the high activity levels of the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) in glioma cells. Herein, we used an injectable matrix metalloproteinase (MMP) enzyme responsive hydrogel that loaded TMZ and O6-benzylamine (BG) (MGMT inhibitor) for eradicating residual TMZ-resistant gliomas after surgery. The hydrogels exhibited three features: (1) TMZ and BG could be encapsulated within the hydrophobic lamellae of the hydrogel to form Tm (TMZ + BG) hydrogels; (2) The hydrogels could release TMZ and BG in response to the high concentration of MMP enzymes after glioma surgery; (3) The hydrogels could increase local TMZ concentration and reduce side effects of BG. In vivo, the Tm (TMZ + BG) hydrogels inhibited the MGMT expression and sensitized TMZ-resistant glioma cells to TMZ. Moreover, the Tm (TMZ + BG) hydrogels effectively reduced the recurrence of TMZ-resistant glioma after surgery and significantly enhanced the efficiency of TMZ to inhibit glioma growth. Together, these data suggest that an MMP-responsive hydrogel is a promising localized drug delivery method to inhibit TMZ-resistant glioma recurrence after surgery.


Assuntos
Dacarbazina , Glioma , Antineoplásicos Alquilantes/uso terapêutico , Linhagem Celular Tumoral , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Glioma/tratamento farmacológico , Humanos , Hidrogéis/farmacologia , Temozolomida/farmacologia , Temozolomida/uso terapêutico
13.
Saudi J Biol Sci ; 23(3): 348-52, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27081359

RESUMO

Illicium verum, whose extractives can activate the demic acquired immune response, is an expensive medicinal plant. However, the rich extractives in I. verum biomass were seriously wasted for the inefficient extraction and separation processes. In order to further utilize the biomedical resources for the good acquired immune response, the four extractives were obtained by SJYB extraction, and then the immunology moleculars of SJYB extractives were identified and analyzed by GC-MS. The result showed that the first-stage extractives contained 108 components including anethole (40.27%), 4-methoxy-benzaldehyde (4.25%), etc.; the second-stage extractives had 5 components including anethole (84.82%), 2-hydroxy-2-(4-methoxy-phenyl)-n-methyl-acetamide (7.11%), etc.; the third-stage extractives contained one component namely anethole (100%); and the fourth-stage extractives contained 5 components including cyclohexyl-benzene (64.64%), 1-(1-methylethenyl)-3-(1-methylethyl)-benzene (17.17%), etc. The SJYB extractives of I. verum biomass had a main retention time between 10 and 20 min what's more, the SJYB extractives contained many biomedical moleculars, such as anethole, eucalyptol, [1S-(1α,4aα,10aß)]-1,2,3,4,4a,9,10,10a-octahydro-1,4a-dimethyl-7-(1-methylethyl)-1-phenanthrenecarboxylic acid, stigmast-4-en-3-one, γ-sitosterol, and so on. So the functional analytical results suggested that the SJYB extractives of I. verum had a function in activating the acquired immune response and a huge potential in biomedicine.

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