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1.
Int J Pharm ; 665: 124697, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39270762

RESUMO

Glioblastoma multiforme (GBM) is a highly aggressive form of primary brain tumor in adults, which unfortunately has an abysmal prognosis and poor survival rates. The reason behind the poor success rate of several FDA-approved drug is mainly attributed to insufficient drug distribution to the tumor site across the blood-brain barrier (BBB) and induction of resistance. In this study, we have developed a novel nanotherapeutic approach to achieve our goal. PLGA-based nanoencapsulation of both Temozolomide (TMZ) and EGFR inhibitor 3,3'-diindoyl methane (DIM) in a combinatorial approach enhances the delivery of them together. Their synergistic mode of actions, significantly enhances the cytotoxic effect of TMZ in vitro and in vivo. Moreover, the dual-loaded nanoformulation works more efficiently on DNA damage and apoptosis, resulting in a several-fold reduction in tumor burden in vivo, systemic drug toxicity, and increased survival. These findings suggest the preclinical potential of this new treatment strategy.

2.
Int J Biol Macromol ; 279(Pt 4): 135405, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245110

RESUMO

The use of submucosal injection is crucial for satisfactory submucosal elevation in the early resection of flat polyps originating from the gastrointestinal tract (GIT). Injectable hydrogels derived from natural polypeptides are attractive candidates due to their excellent biocompatibility and easy gelation properties. However, most of the reported hydrogels are not the class of catheter delivery materials due to quick gelation, high inherent viscosity, and injection clogging. This study presents a novel injectable shear-thinning hydrogel platform of small molecules (nonanal) modified gelatin polymer, which offers a promising submucosal injection for effective removal of polyps from GIT. Physicochemical characterizations of hydrogel demonstrate the suitable features as an effective submucosal injection, including shear thinning property, self-assembly, methylene blue dye encapsulation, flow behavior, stability, syringeability (18 G, 21 G, and 24 G needles) and fibrous morphology. Ex vivo investigations of developed submucosal formulation on goat intestines demonstrate the enhanced visibility of cushions and the ability to produce stable, long-lasting cushions of about 8.07 mm up to ∼60 min of submucosal injection. The rapid blood clotting behavior of hydrogel was observed in about 120 s without compromising hemocompatibility with the hemolysis of about 3.77 % only. In vitro biocompatibility of the hydrogel was also verified using the HepG2 and nHDF cells. In vivo study depicts desirable biocompatibility, a non-toxic organ profile, and optimal cushion height in mice models. Studies established the foundation of novel submucosal fluid to improve the therapeutic outcomes of early resection for gastrointestinal polyps.

3.
Biochim Biophys Acta Mol Cell Res ; 1871(8): 119827, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39187067

RESUMO

Colorectal cancer (CRC) presents ongoing challenges due to limited treatment effectiveness and a discouraging prognosis, underscoring the need for ground-breaking therapeutic approaches. This review delves into the pivotal role of E3 ubiquitin ligases and deubiquitinases (DUBs), underscoring their role as crucial regulators for tumor suppression and oncogenesis in CRC. We spotlight the diverse impact of E3 ligases and DUBs on CRC's biological processes and their remarkable versatility. We closely examine their specific influence on vital signaling pathways, particularly Wnt/ß-catenin and NF-κB. Understanding these regulatory mechanisms is crucial for unravelling the complexities of CRC progression. Importantly, we explore the untapped potential of E3 ligases and DUBs as novel CRC treatment targets, discussing aspects that may guide more effective therapeutic strategies. In conclusion, our concise review illuminates the E3 ubiquitin ligases and deubiquitinases pivotal role in CRC, offering insights to inspire innovative approaches for transforming the treatment landscape in CRC.

4.
Life Sci ; 356: 123018, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39214286

RESUMO

GBM is the most common, aggressive, and intracranial primary brain tumor; it originates from the glial progenitor cells, has poor overall survival (OS), and has limited treatment options. In this decade, GBM immunotherapy is in trend and preferred over several conventional therapies, due to their better patient survival outcome. This review explores the clinical trials of several immunotherapeutic approaches (immune checkpoint blockers (ICBs), CAR T-cell therapy, cancer vaccines, and adoptive cell therapy) with their efficacy and safety. Despite significant progress, several challenges (viz., immunosuppressive microenvironment, heterogeneity, and blood-brain barrier (BBB)) were experienced that hamper their immunotherapeutic potential. Furthermore, these challenges were clinically studied to be resolved by multiple combinatorial approaches, discussed in the later part of the review. Thus, this review suggests the clinical use and potential of immunotherapy in GBM and provides the holistic recent knowledge and future perspectives.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Imunoterapia , Microambiente Tumoral , Humanos , Imunoterapia/métodos , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/imunologia , Glioblastoma/terapia , Glioblastoma/imunologia , Microambiente Tumoral/imunologia , Vacinas Anticâncer/uso terapêutico , Vacinas Anticâncer/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Animais , Barreira Hematoencefálica/imunologia
5.
Anal Methods ; 16(19): 3007-3019, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38695537

RESUMO

We present a colorimetric probe based on polyvinylpyrrolidone-capped gold nanoparticles (PVP-AuNPs) that is sensitive and selective for cysteine (Cys). A microfluidic paper-based analytical device (µ-PAD) with embedded dried PVP-AuNPs at the polyethersulfone (PES) paper surface is used for Cys detection. When thiol molecules attach to PVP-AuNPs in the presence of Cys, they clump together, and this causes the solution's color to shift from red to blue within 5 minutes. The device is capable of detecting Cys levels between 1.0 µM and 50.0 µM with a limit of detection (LOD) of 0.2 µM under optimized conditions. The stability of the µ-PAD was tested for 100 days, demonstrating re-dispersibility to detect Cys levels in blood. Dried PVP-AuNP-µPADs were integrated with blood plasma separation modules for point-of-care (POC) Cys detection. Consequently, the device shows potential as a self-sustaining, quantification platform with a recovery percentage ranging from 98.44 to 111.9 in clinical samples.


Assuntos
Colorimetria , Cisteína , Ouro , Limite de Detecção , Nanopartículas Metálicas , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Ouro/química , Cisteína/sangue , Cisteína/química , Nanopartículas Metálicas/química , Humanos , Colorimetria/métodos , Colorimetria/instrumentação , Povidona/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
6.
Genes Dis ; 10(4): 1318-1350, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37397537

RESUMO

Maintaining the balance between eliciting immune responses against foreign proteins and tolerating self-proteins is crucial for maintenance of homeostasis. The functions of programmed death protein 1 (PD-1) and its ligand programmed death ligand 1 (PD-L1) are to inhibit immune responses so that over-reacting immune cells does not cause any damage to its own body cells. However, cancer cells hijack this mechanism to attenuate immune cells functions and create an immunosuppressive environment that fuel their continuous growth and proliferation. Over the past few years' rapid development in cancer immunotherapy has opened a new avenue in cancer treatment. Blockade of PD-1 and PD-L1 has become a potential strategy that rescue the functions of immune cells to fight against cancer with high efficacy. Initially, immune checkpoint monotherapies were not very successful, making breast cancer less immunogenic. Although, recent reports support the presence of tumor infiltrating lymphocytes (TILs) in breast cancer that make it favorable for PD-1/PD-L1 mediated immunotherapy, which is effective in PD-L1 positive patients. Recently, anti-PD-1 (pembrolizumab) and anti-PD-L1 (atezolizumab) gets FDA approval for breast cancer treatment and make PD-1/PD-L1 immunotherapy is meaningful for further research. Likewise, this article gathered understanding of PD-1 and PD-L1 in recent years, their signaling networks, interaction with other molecules, regulations of their expressions and functions in both normal and tumor tissue microenvironments are crucial to find and design therapeutic agents that block this pathway and improve the treatment efficacy. Additionally, authors collected and highlighted most of the important clinical trial reports on monotherapy and combination therapy.

7.
Ann Med Surg (Lond) ; 85(4): 665-669, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37113856

RESUMO

Helicobacter pylori infection is seropositive in ~50% of people globally. Therefore, this study was conducted to evaluate its prevalence in dyspepsia patients. Methods: A cross-sectional study was conducted at Jinnah Postgraduate Medical Centre (JPMC) from January to June 2022 to find out the prevalence and risk factors of H. pylori in dyspepsia patients. A prevalidated questionnaire was used to collect the data from 180 patients. This study adheres to the principles outlined in the Helsinki Declaration. The χ 2-test was applied, and the odds ratio and 95% CI were calculated to find the association of H. pylori with the risk factors. Results: A total of 180 patients were enrolled in this study, of whom, 73 (40.6%) patients were male and 107 (59.4%) were female. In seropositive H. pylori patients, 80 (60.6%) patients had nausea or vomiting, 110 (83.3%) patients were found to have flatulence, 128 (97.7%) patients were experiencing frequent burping, and 114 (86.4%) patients were having epigastric pain. The household member greater than 4, smoking, rural area residence, NSAIDs consumption, BMI greater than 25, O+ blood group, and Rhesus positive status were significantly associated with H. pylori with a P value of less than 0.05. Conclusion: This study concludes that the prevalence of H. pylori in our population is high, and the risk factors identified are lower class, BMI greater than 25, smoking, O+ blood group, NSAID consumption, rural area residence, household member greater than 4, Rhesus positive status, and the symptoms of nausea or vomiting, frequent burping, epigastric pain, and flatulence. Patients with an increased number of risk factors should be taken into consideration for an appropriate checkup.

8.
Genes Dis ; 9(6): 1521-1555, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36157498

RESUMO

The carboxy-terminus of Hsp70-interacting protein (CHIP) is a ubiquitin ligase and co-chaperone belonging to Ubox family that plays a crucial role in the maintenance of cellular homeostasis by switching the equilibrium of the folding-refolding mechanism towards the proteasomal or lysosomal degradation pathway. It links molecular chaperones viz. HSC70, HSP70 and HSP90 with ubiquitin proteasome system (UPS), acting as a quality control system. CHIP contains charged domain in between N-terminal tetratricopeptide repeat (TPR) and C-terminal Ubox domain. TPR domain interacts with the aberrant client proteins via chaperones while Ubox domain facilitates the ubiquitin transfer to the client proteins for ubiquitination. Thus, CHIP is a classic molecule that executes ubiquitination for degradation of client proteins. Further, CHIP has been found to be indulged in cellular differentiation, proliferation, metastasis and tumorigenesis. Additionally, CHIP can play its dual role as a tumor suppressor as well as an oncogene in numerous malignancies, thus acting as a double agent. Here, in this review, we have reported almost all substrates of CHIP established till date and classified them according to the hallmarks of cancer. In addition, we discussed about its architectural alignment, tissue specific expression, sub-cellular localization, folding-refolding mechanisms of client proteins, E4 ligase activity, normal physiological roles, as well as involvement in various diseases and tumor biology. Further, we aim to discuss its importance in HSP90 inhibitors mediated cancer therapy. Thus, this report concludes that CHIP may be a promising and worthy drug target towards pharmaceutical industry for drug development.

9.
Asian Pac J Cancer Prev ; 19(11): 3265-3270, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30486630

RESUMO

The region of head and neck is critical for respiration, nutrition, and speech. The management of laryngeal tumours can stimulate mutilations and cosmetic deformities and worsen the life. A "non-operative approach" is preferred for patients to whom radiation following surgery, possibly, will direct severe functional destruction predominantly in advanced stage patients having a bulk of carcinoma larynx. The case material for the study was selected from the cross-section of patients registered at the J. K. Cancer Institute, Kanpur. Histologically squamous cell carcinoma 64 patients were registered and equally and randomly placed into Arm I and Arm II. "Arm I" patients and "Arm II" was comprised of randomly selected 64 patients, having histopathologically proven squamous cell carcinoma of the larynx. All patients (32 patients) belonging to "Arm I" received concurrent chemoradiotherapy of Inj. Cisplatin 100 mg/m2 for three-weekly underwent EBRT with 60 Co/LINAC and photon radiation of 70 Gy in 35 fractions for 7 weeks (2 parallel opposed fields). All the patients (32 patients) belongs to "Arm II" received chemo boost as Inj. Cisplatin 6 mg/m2 on last 15 fractions of treatment underwent EBRT with 60 Co/ LINAC photon radiation of 70 Gy in 35 fractions for 7 weeks. Radiotherapy was delivered in supine position by parallel opposing fields including the primary tumour, disease extension, and neck nodes. The study concluded that the loco-regional responses are analogous in Arm I and Arm 2, however Arm II had additional treatment allied toxicities and resulting from numerous of treatment breaks.


Assuntos
Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Neoplasias Laríngeas/terapia , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/patologia , Criança , Pré-Escolar , Cisplatino/uso terapêutico , Estudos Transversais , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Adulto Jovem
10.
ACS Appl Mater Interfaces ; 10(33): 27589-27602, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30048112

RESUMO

Targeting dendritic cells (DCs), either ex vivo (Ex. Sipuleucel-T) or in vivo, for stimulating cellular immunity has been a leading approach for cancer vaccines. We have rationally engineered a nanoparticle (NP)-based delivery system for vaccines (InAc-NPs) using inulin acetate (InAc) as the polymer to target DCs. The material and the antigen-encapsulated InAc-NPs (∼190 nm in diameter) were characterized for their physicochemical properties. As a potent vaccine adjuvant, InAc-NPs activated TLR4 on multiple immune cells, including DCs and primary swine and human cells, to secrete various cytokines as detected by enzyme-linked immunosorbent assay and quantitative polymerase chain reaction. In addition, InAc-NPs promoted the maturation of DCs as observed by a decreased phagocytic ability and enhanced capability to activate various maturation markers (MHC-I, MHC-II, CD40, and CD80) quantified using flow cytometry. In mice, the InAc-NPs produced strong serum antibody titers (total IgG, IgG1, and IgG2a) against the encapsulated antigen (ovalbumin) similar to complete Freund's adjuvant. Additionally, as a dose-sparing delivery system, antigen delivered through InAc-NPs generated higher antibody titers (IgG1, 1.57 times; IgG-total, 1.66 times; and IgG2a, 29.8 times) even at 100 times less antigen dose. High amounts of cytokines representing both humoral (IL4 and IL10) and cell-mediated (IL2 and IFN-γ) immunities were secreted from splenocytes of mice immunized with InAc-NPs. Importantly, InAc-NPs provided complete protection in 100% of the vaccinated mice from metastasis of intravenously injected melanoma cells (B16-F10) to lungs. In addition, the InAc-NPs were cleared from the injection site within 30 h of injection (in vivo imaging) and displayed no toxicity at the injection site (histology). The current study demonstrates that the multifunctional InAc-based nanovaccine delivery system has potential applications in cancer immunotherapy and delivering vaccines against various infectious diseases.


Assuntos
Células Dendríticas , Adjuvantes Imunológicos , Animais , Antígenos , Vacinas Anticâncer , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas , Ácido Poliglicólico , Suínos
11.
J Control Release ; 261: 263-274, 2017 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-28669593

RESUMO

New and improved vaccines are needed against challenging diseases such as malaria, tuberculosis, Ebola, influenza, AIDS, and cancer. The majority of existing vaccine adjuvants lack the ability to significantly stimulate the cellular immune response, which is required to prevent the aforementioned diseases. This study designed a novel particulate based pathogen-mimicking vaccine delivery system (PMVDS) to target antigen-presenting-cells (APCs) such as dendritic cells. The uniqueness of PMVDS is that the polymer used to prepare the delivery system, Inulin Acetate (InAc), activates the innate immune system. InAc was synthesized from the plant polysaccharide, inulin. PMVDS provided improved and persistent antigen delivery to APCs as an efficient vaccine delivery system, and simultaneously, activated Toll-Like Receptor-4 (TLR-4) on APCs to release chemokine's/cytokines as an immune-adjuvant. Through this dual mechanism, PMVDS robustly stimulated both the humoral (>32 times of IgG1 levels vs alum) and the cell-mediated immune responses against the encapsulated antigen (ovalbumin) in mice. More importantly, PMVDS stimulated both cytotoxic T cells and natural killer cells of cell-mediated immunity to provide tumor (B16-ova-Melanoma) protection in around 40% of vaccinated mice and significantly delayed tumor progression in rest of the mice. PMVDS is a unique bio-active vaccine delivery technology with broader applications for vaccines against cancer and several intracellular pathogens, where both humoral and cellular immune responses are desired.


Assuntos
Vacinas Anticâncer/administração & dosagem , Sistemas de Liberação de Medicamentos , Inulina/administração & dosagem , Vacinas/administração & dosagem , Acetatos , Adjuvantes Imunológicos/administração & dosagem , Animais , Antígenos/administração & dosagem , Antígenos/imunologia , Vacinas Anticâncer/imunologia , Quimiocinas/imunologia , Citocinas/imunologia , Humanos , Imunidade Celular , Imunidade Humoral , Inulina/imunologia , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Suínos , Vacinas/imunologia
12.
Faraday Discuss ; 199: 115-128, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28422194

RESUMO

Application of an electric field on an oil droplet floating on the surface of a deionized water bath showed interesting motions such as spreading, oscillation, and ejection. The electric field was generated by connecting a pointed platinum cathode at the top of the oil droplet and a copper anode coated with polymer at the bottom of the water layer. The experimental setup mimicked a conventional electrowetting setup with the exception that the oil was spread on a soft and deformable water isolator. While at relatively lower field intensities we observed spreading of the droplet, at intermediate field intensities the droplet oscillated around the platinum cathode, before ejecting out at a speed as high as ∼5 body lengths per second at even stronger field intensities. The experiments suggested that when the electric field was ramped up abruptly to a particular voltage, any of the spreading, oscillation, or ejection motions of the droplet could be engendered at lower, intermediate and higher field intensities, respectively. However, when the field was ramped up progressively by increasing by a definite amount of voltage per unit time, all three aforementioned motions could be generated simultaneously with the increase in the field intensity. Interestingly, when the aforementioned setup was placed on a magnet, the droplet showed a rotational motion under the influence of the Lorentz force, which was generated because of the coupling of the weak leakage current with the externally applied magnetic field. The spreading, oscillation, ejection, and rotation of the droplet were found to be functions of the oil-water interfacial tension, viscosity, and size of the oil droplet. We developed simple theoretical models to explain the experimental results obtained. Importantly, rotating at a higher speed broke the droplet into a number of smaller ones, owing to the combined influence of the spreading due to the centripetal force and the shear at the oil-water interface. While the oscillatory and rotational motions of the incompressible droplet could be employed as stirrers or impellers inside microfluidic devices for mixing applications, the droplet ejection could be employed for futuristic applications such as payload transport or drug delivery.

13.
Int J Pharm ; 500(1-2): 32-41, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26792170

RESUMO

Micellization offers several advantages for the delivery of water insoluble drugs including a nanoparticulate 'core-shell' delivery system for drug targeting. Recently, hydrophobically modified polysaccharides (HMPs) are gaining recognition as micelle forming polymers to encapsulate hydrophobic drugs. In this manuscript, for the first time, we have evaluated the self-assembling properties of a lauryl carbamate derivative of the poly-fructose natural polymer inulin (Inutec SP1(®) (INT)) to form paclitaxel (PTX) loaded micelles. INT self-assembled into well-defined micellar structures in aqueous environment with a low critical micellar concentration of 27.8 µg/ml. INT micelles exhibited excellent hemocompatibility and low toxicity to cultured cells. PTX loaded INT micelles exhibited a mean size of 256.37 ± 10.45 nm with excellent drug encapsulation efficiency (95.66 ± 2.25%) and loading (8.69 ± 0.22%). PTX loaded micelles also displayed sustained release of PTX and enhanced anti-cancer efficacy in-vitro in mouse melanoma cells (B16F10) compared to Taxol formulation with Cremophor EL as solvent. In addition, PTX loaded INT micelles exhibited comparable in-vivo antitumor activity in B16F10 allograft mouse model at half the dose of Taxol. In conclusion, INT offers safe, inexpensive and natural alternative to widely used PEG-modified polymers for the formulation of micellar delivery systems for paclitaxel.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Inulina/administração & dosagem , Paclitaxel/administração & dosagem , Administração Intravenosa , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Inulina/química , Inulina/farmacologia , Inulina/uso terapêutico , Masculino , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Micelas , Paclitaxel/química , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Carga Tumoral/efeitos dos fármacos
14.
Adv Healthc Mater ; 5(5): 602-9, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26799634

RESUMO

Skin-penetrating peptides (SPPs) are attracting increasing attention as a non-invasive strategy for transdermal delivery of therapeutics. The identification of SPP sequences, however, currently performed by experimental screening of peptide libraries, is very laborious. Recent studies have shown that, to be effective enhancers, SPPs must possess affinity for both skin keratin and the drug of interest. We therefore developed a computational process for generating and screening virtual libraries of disulfide-cyclic peptides against keratin and cyclosporine A (CsA) to identify SPPs capable of enhancing transdermal CsA delivery. The selected sequences were experimentally tested and found to bind both CsA and keratin, as determined by mass spectrometry and affinity chromatography, and enhance transdermal permeation of CsA. Four heptameric sequences that emerged as leading candidates (ACSATLQHSCG, ACSLTVNWNCG, ACTSTGRNACG, and ACSASTNHNCG) were tested and yielded CsA permeation on par with previously identified SPP SPACE (TM) . An octameric peptide (ACNAHQARSTCG) yielded significantly higher delivery of CsA compared to heptameric SPPs. The safety profile of the selected sequences was also validated by incubation with skin keratinocytes. This method thus represents an effective procedure for the de novo design of skin-penetrating peptides for the delivery of desired therapeutic or cosmetic agents.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Desenho de Fármacos , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Preparações Farmacêuticas/administração & dosagem , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Administração Cutânea , Adulto , Sequência de Aminoácidos , Sobrevivência Celular/efeitos dos fármacos , Simulação por Computador , Ciclosporina/metabolismo , Ciclosporina/farmacologia , Células Epidérmicas , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinas/metabolismo , Espectrometria de Massas , Biblioteca de Peptídeos , Peptídeos/química , Peptídeos/toxicidade , Termodinâmica
15.
J Mater Chem B ; 4(48): 7950-7960, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263785

RESUMO

Vaccine adjuvants are an essential part of modern vaccine design, especially against intracellular pathogens such as M. tuberculosis, malarial parasite, HIV, influenza virus and Ebola. The present work offers a unique approach to designing novel vaccine adjuvants by identifying polymers that mimic "pathogen associated molecular patterns" (PAMPS) and engineering an immune-active particulate vaccine delivery system that uses the polymer. By using this strategy, we report the discovery of the first plant polymer based toll-like receptor-4 (TLR-4) agonist, inulin acetate (InAc). InAc was synthesised from the plant polysaccharide inulin. Inulin acetate as a polymer and particles prepared using InAc were characterised using various physicochemical techniques. The TLR-4 agonistic activity of InAc was established in multiple immune, microglial, dendritic, peripheral blood mononuclear (human and swine) and genetically modified epithelial cells (HEK293) that exclusively express TLR-4 on their surface. InAc activated all the above-mentioned cells to release proliferative cytokines; however, InAc failed to activate when the were cells either pre-incubated with a TLR-4 specific antagonist or isolated from mice deficient in adapter proteins involved in TLR signalling (Mal/MyD88). Antigen encapsulated microparticles prepared with TLR-4 agonist InAc mimicked pathogens to offer improved antigen delivery to dendritic cells compared to soluble antigen (47 times) or antigen encapsulated poly(lactic-co-glycolic acid) (PLGA) particles (1.57 times). In conclusion, InAc represents a novel polymer-based modern vaccine adjuvant targeting specific signalling pathways of the innate immune system, which could be formulated into a platform vaccine delivery system against cancer and viral diseases.

16.
Adv Healthc Mater ; 4(15): 2297-305, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26371956

RESUMO

Combinations of polymer conjugates affording in situ gelation hold promise for treatment of pathological cavities (e.g., arthritis) and sustained drug release. In particular, hyaluronic acid (HA) functionalized with reactive groups is regarded as an excellent biomaterial due to its tunable cross-linking kinetics and mechanical properties. HA-based reagents, however, can be irritating to surrounding tissues due to the reactivity of pendant groups, and their fast gelation kinetics can result in poor cavity filling. In this study, a biocompatible "click" reaction between cyanobenzothiazole (CBT) and d-cysteine (d-Cys) is employed to produce HA-based conjugates for in situ gelation. Rheological studies conducted on a gel obtained from the combination of HA-CBT and HA-d-Cys indicate optimal gelation time and mechanical properties. Further, in vitro studies on porcine skin demonstrate the ability of the gel to form in situ upon subcutaneous injection or topical application, and to act as a reservoir for sustained release of protein therapeutics. Finally, the safety of the HA-based conjugates is demonstrated on human keratinocytes. The presented results demonstrate the applicability of the binary mixture for in situ gelation and the potential of the proposed system for a variety of biomedical applications.


Assuntos
Ácido Hialurônico/química , Hidrogéis/química , Pele/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Polímeros , Reologia , Pele/metabolismo , Suínos , Engenharia Tecidual
17.
Drug Deliv Transl Res ; 5(5): 523-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25939432

RESUMO

The balance of efficacy and safety of topical corticosteroids (TCs) depends on their ability to penetrate into and be retained within the skin. Here, we evaluated the ability of SPACE™ peptide to enhance epidermal delivery and localization of three model TCs. In vitro and in vivo skin penetration studies were performed to evaluate penetration of TCs into and across the skin in the presence of various formulations of SPACE™ peptide. Topical formulations of corticosterone containing free SPACE™ peptide produced significantly enhanced epidermal penetration and localization. Ratio of drug deposition in the skin and receiver (efficacy/safety, indicative of ratio of local to systemic uptake) exhibited higher values for SPACE™ peptide-based formulation as compared to aqueous and hydroethanolic solutions and Cortizone™ cream. Mass spectrometry analysis showed that SPACE™ peptide associates with corticosterone, which may explain its enhanced retention effect. SPACE™ peptide also enhanced dermal retention of two more TCs (hydrocortisone and triamcinolone acetonide) compared to the vehicle control. An in vivo study in mice further established the ability of SPACE™ peptide to enhance skin retention of hydrocortisone without producing elevated blood concentrations. These results show that SPACE™ peptide is an effective additive to the formulation for enhanced skin localization of topical steroids.


Assuntos
Corticosteroides/administração & dosagem , Sistemas de Liberação de Medicamentos , Epiderme/metabolismo , Excipientes/administração & dosagem , Peptídeos/administração & dosagem , Administração Cutânea , Corticosteroides/química , Corticosteroides/farmacocinética , Animais , Excipientes/química , Excipientes/farmacocinética , Técnicas In Vitro , Camundongos Pelados , Peptídeos/química , Peptídeos/farmacocinética , Suínos , Distribuição Tecidual
18.
J Control Release ; 210: 198-207, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25921087

RESUMO

Combinations of topoisomerase inhibitors I and II have been found to synergistically inhibit cancer cell growth in vitro, yet clinical studies of these types of combinations have not progressed beyond phase II trials. The results of clinical combinations of topoisomerase (top) I and II inhibitors typically fall within one of two categories: little to no improvement in therapeutic efficacy, or augmented toxicity compared to the single drug counterparts. Hence, despite the promising activity of top I and II inhibitor combinations in vitro, their clinical applicability has not been realized. Here, we report the use of polymer-drug conjugates as a means to co-deliver synergistic doses of top I and II inhibitors camptothecin (CPT) and doxorubicin (DOX) to tumors in vivo in a 4T1 breast cancer model. At specific molar ratios, DOX and CPT were found to be among the most synergistic combinations reported to date, with combination indices between 0.01 and 0.1. The identified optimal ratios were controllably conjugated to hyaluronic acid, and elicited significant tumor reduction of murine 4T1 breast cancer model when administered intravenously. This study elucidates a method to identify synergistic drug combinations and translate them to in vivo by preserving the synergistic ratio via conjugation to a carrier polymer, thus opening a promising approach to translate drug combinations to clinically viable treatment regimens.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Camptotecina/administração & dosagem , Camptotecina/química , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Sinergismo Farmacológico , Feminino , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/química , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Inibidores da Topoisomerase I/administração & dosagem , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase II/administração & dosagem , Inibidores da Topoisomerase II/química , Carga Tumoral/efeitos dos fármacos
19.
Glia ; 63(5): 754-67, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25690519

RESUMO

Whole brain irradiation remains important in the management of brain tumors. Although necessary for improving survival outcomes, cranial irradiation also results in cognitive decline in long-term survivors. A chronic inflammatory state characterized by microglial activation has been implicated in radiation-induced brain injury. We here provide the first comprehensive transcriptional profile of irradiated microglia. Fluorescence-activated cell sorting was used to isolate CD11b+ microglia from the hippocampi of C57BL/6 and Balb/c mice 1 month after 10 Gy cranial irradiation. Affymetrix gene expression profiles were evaluated using linear modeling and rank product analyses. One month after irradiation, a conserved irradiation signature across strains was identified, comprising 448 and 85 differentially up- and downregulated genes, respectively. Gene set enrichment analysis demonstrated enrichment for inflammation, including M1 macrophage-associated genes, but also an unexpected enrichment for extracellular matrix and blood coagulation-related gene sets, in contrast previously described microglial states. Weighted gene coexpression network analysis confirmed these findings and further revealed alterations in mitochondrial function. The RNA-seq transcriptome of microglia 24-h postradiation proved similar to the 1-month transcriptome, but additionally featured alterations in apoptotic and lysosomal gene expression. Reanalysis of published aging mouse microglia transcriptome data demonstrated striking similarity to the 1-month irradiated microglia transcriptome, suggesting that shared mechanisms may underlie aging and chronic irradiation-induced cognitive decline. GLIA 2015;63:754-767.


Assuntos
Envelhecimento/patologia , Encéfalo/citologia , Irradiação Craniana , Microglia/metabolismo , Microglia/efeitos da radiação , Transcriptoma/efeitos da radiação , Envelhecimento/metabolismo , Animais , Encéfalo/efeitos da radiação , Antígeno CD11b/metabolismo , Polaridade Celular/efeitos da radiação , Feminino , Citometria de Fluxo , Redes Reguladoras de Genes/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Especificidade da Espécie , Fatores de Tempo
20.
World Neurosurg ; 83(6): 1135-40, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25683128

RESUMO

OBJECTIVE: To review the pathophysiology and therapeutic modalities availble for Nelson syndrome. METHODS: We reviewed the current literature including managment for Nelson syndrome. RESULTS: For patients with NS, surgical intervention is often the first-line therapy. With refractory NS or tumors with extrasellar involvement, radiosurgery offers an important alternative or adjuvant option. Pharmacologic interventions have demonstrated limited usefulness, although recent evidence supports the feasibility of a novel somatostatin analog for patients with NS. Modern neuroimaging, improved surgical techniques, and the advent of stereotactic radiotherapy have transformed the management of NS. CONCLUSIONS: An up-to-date understanding of the pathophysiology underlying Nelson Syndrome and evidence-based management is imperative. Early detection may allow for more successful therapy in patients with Nelson Syndrome. Improved radiotherapeutic interventions and rapidly evolving pharmacologic therapies offer an opportunity to create targeted, multifocal treatment regiments for patients with Nelson Syndrome.


Assuntos
Adrenalectomia , Síndrome de Nelson/diagnóstico , Síndrome de Nelson/terapia , Radiocirurgia , Somatostatina/análogos & derivados , Hormônio Adrenocorticotrópico/sangue , Diagnóstico Precoce , Medicina Baseada em Evidências , Humanos , Síndrome de Nelson/metabolismo , Somatostatina/uso terapêutico
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