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1.
Int J Mol Sci ; 25(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38674114

RESUMO

Preeclampsia, a serious complication of pregnancy, involves intricate molecular and cellular mechanisms. Fetal microchimerism, where fetal cells persist within maternal tissues and in circulation, acts as a mechanistic link between placental dysfunction and maternal complications in the two-stage model of preeclampsia. Hormones, complements, and cytokines play pivotal roles in the pathophysiology, influencing immune responses, arterial remodeling, and endothelial function. Also, soluble HLA-G, involved in maternal-fetal immune tolerance, is reduced in preeclampsia. Hypoxia-inducible factor 1-alpha (Hif-α) dysregulation leads to placental abnormalities and preeclampsia-like symptoms. Alterations in matrix metalloproteinases (MMPs), endothelins (ETs), chemokines, and cytokines contribute to defective trophoblast invasion, endothelial dysfunction, and inflammation. Preeclampsia's genetic complexity includes circRNAs, miRNAs, and lncRNAs. CircRNA_06354 is linked to early-onset preeclampsia by influencing trophoblast invasion via the hsa-miR-92a-3p/VEGF-A pathway. The dysregulation of C19MC, especially miR-519d and miR-517-5p, affects trophoblast function. Additionally, lncRNAs like IGFBP1 and EGFR-AS1, along with protein-coding genes, impact trophoblast regulation and angiogenesis, influencing both preeclampsia and fetal growth. Besides aberrations in CD31+ cells, other potential biomarkers such as MMPs, soluble HLA-G, and hCG hold promise for predicting preeclampsia and its complications. Therapeutic interventions targeting factors such as peroxisome PPAR-γ and endothelin receptors show potential in mitigating preeclampsia-related complications. In conclusion, preeclampsia is a complex disorder with a multifactorial etiology and pathogenesis. Fetal microchimerism, hormones, complements, and cytokines contribute to placental and endothelial dysfunction with inflammation. Identifying novel biomarkers and therapeutic targets offers promise for early diagnosis and effective management, ultimately reducing maternal and fetal morbidity and mortality. However, further research is warranted to translate these findings into clinical practice and enhance outcomes for at-risk women.


Assuntos
Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Biomarcadores , Hormônios/metabolismo , MicroRNAs/genética , Placenta/metabolismo , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/fisiopatologia , Trofoblastos/metabolismo
2.
Int J Mol Sci ; 24(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37569564

RESUMO

Drug combination therapy is a key approach in cancer treatments, aiming to improve therapeutic efficacy and overcome drug resistance. Evaluation of intracellular response in cancer cells to drug treatment may disclose the underlying mechanism of drug resistance. In this study, we aimed to investigate the effect of osimertinib, a tyrosine kinase inhibitor (TKI), and a curcumin derivative, 35d, on HCC827 cells and tumors by analyzing alterations in metabolome and related regulations. HCC827 tumor-bearing SCID mice and cultured HCC827 cells were separately examined. The treatment comprised four conditions: vehicle-only, 35d-only, osimertinib-only, and a combination of 35d and osimertinib. The treated tumors/cells were subsequently subjected to metabolomics profiling, fatty acyl analysis, mitochondrial potential measurement, and cell viability assay. Osimertinib induced changes in the ratio of short-chain (SC) to long-chain (LC) fatty acyls, particularly acylcarnitines (ACs), in both tumors and cells. Furthermore, 35d enhanced this effect by further lowering the SC/LC ratio of most ACs. Osimertinib and 35d also exerted detrimental effects on mitochondria through distinct mechanisms. Osimertinib upregulated the expression of carnitine palmitoyltransferase I (CPTI), while 35d induced the expression of heat shock protein 60 (HSP60). The alterations in ACs and CPTI were correlated with mitochondrial dysfunction and inhibited cell growth. Our results suggest that osimertinib and 35d disrupted the fatty acyl metabolism and induced mitochondrial stress in cancer cells. This study provides insights into the potential application of fatty acyl metabolism inhibitors, such as osimertinib or other TKIs, and mitochondrial stress inducers, such as curcumin derivatives, as combination therapy for cancer.


Assuntos
Curcumina , Neoplasias Pulmonares , Camundongos , Animais , Curcumina/farmacologia , Curcumina/uso terapêutico , Camundongos SCID , Neoplasias Pulmonares/metabolismo , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Mitocôndrias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Mutação
3.
Hum Exp Toxicol ; 42: 9603271221149663, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36625148

RESUMO

Ferroptosis is a new type of cell death marked by iron and lipid ROS accumulation. GPX4 is one of the glutathione peroxidases known to regulate ferroptosis tightly. On the other hand, Nrf2 also plays a vital role in ferroptosis as it targets genes related to oxidant defense. Herein, we employed beas-2 human epithelial cells treated with a low concentration of RSL3 to induce ferroptosis. To study the protective role of Nrf2, we used ML385 as its specific inhibitor. A combination of ML385 and a low concentration of RSL3 synergistically induced more toxicity to RSL3. Furthermore, we found that mitochondrial ROS is elevated in ML385 and RSL3 combination group. In addition, Mito TEMPOL application successfully prevents the upregulation of mitochondrial ROS, lipid ROS, reduces the toxicity of RSL3, restores the antioxidant capacity of the cells, and mitochondrial functions reflected by mitochondrial membrane potential and mitochondrial oxidative phosphorylation system (OXPHOS) expression. Altogether, our study demonstrated that Nrf2 inhibition by ML385 induces more toxicity when combined with RSL3 through the elevation of mitochondrial ROS and disruption of mitochondrial function.


Assuntos
Ferroptose , Humanos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Células Epiteliais/metabolismo , Pulmão/metabolismo , Mitocôndrias/metabolismo , Lipídeos
4.
Dose Response ; 20(4): 15593258221131646, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387775

RESUMO

Ethanol extracts of Cnidii Fructus, the dried fruits of Cnidium monnieri (L.) Cusson, have been externally applied in the treatment of Trichomonas vaginalis. However, the precise identity of the major constituents responsible for activity against T. vaginalis is unknown, but there is probability they are coumarin derivatives. In this study, the anti-Trichomonas activity of 4 major coumarin derivative constituents of Cnidii Fructus, namely, osthole, xanthotoxin, isopimpinellin, and bergapten, was characterized in terms of the resulting kinetics of growth and morphology of T. vaginalis upon treatment. The results demonstrated that osthole and xanthotoxol had significant trichomonacidal ability, while isopimpinellin and bergapten displayed low or no inhibitory efficacy toward T. vaginalis parasites. Our study suggests that the coumarin derivatives osthole and xanthotoxol can be potentially used as a basis for the development and design of new drugs for application in alternative or synergistic therapy against T. vaginalis.

5.
Mater Today Bio ; 17: 100482, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36388459

RESUMO

Recently, combining immunotherapy and chemotherapy has become a promising strategy to treat cancer. However, this therapeutic strategy still has its limitations because of the adverse effects caused by the simultaneous administration of multiple therapeutic agents. Using nanoparticles is an effective approach to successfully combine these therapies because they can reduce side effects, increase circulation time, and ensure the delivery of cytotoxic agents to tumor tissues. In this study, dual pH-sensitive and tumor microenvironment (TME)-active targeting micelles comprising poly(propyl methacrylate-co-glucosamine/histidine/doxorubicin) (P(PAA-co-GLU/HIS/DOX) and methoxy-poly(ethylene glycol)-block-poly(l-lysine) were prepared to encapsulate an immunomodulator, imiquimod (IMQ). Because these micelles can expose glucose targeting ligands at the TME and pH-dependently release IMQ and DOX, micelles effectively inhibit the growth of 4T1 cells selectively and highly accumulate in 4T1 cells as the pH decreased to 6.5. Moreover, in RAW 264.7 â€‹cells, these micelles prevent cell death and induce M1 macrophage polarization. In 4T1 orthotopic tumor-bearing mice, micelles not only exhibited high tumor accumulation, effective tumor inhibition, and fewer adverse effects, but also dramatically increased the number of mature dendritic cells, activate cytotoxic T cells, and polarize M1-like macrophages in tumor tissues. Overall, these micelles exhibit precise pH responsiveness and ideal drug delivery capabilities for combined chemo- and immunotherapy; these results significantly contribute to the future development of nanomedicines in cancer therapy.

6.
Biomater Adv ; 133: 112597, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35525753

RESUMO

Curcumin is proven to have potent anti-inflammatory activity, but its low water solubility and rapid degradation in physiological conditions limit its clinical use, particularly in intravenous drug delivery. In this study, we fabricated rod-shaped, acid-labile nanogels, using high biosafe and biocompatible polymers, for intravenous application in systemic inflammation treatment. The constituent polymers of the nanogels were prepared via the conjugation of vitamin B6 derivatives, including pyridoxal and pyridoxamine, onto poly(glutamate) with ester bonds. The aldehyde groups of the pyridoxal and amine groups of the pyridoxamine on the polymers enable crosslinking using a Schiff base during the solvent evaporation procedure for the preparation of the rod-shaped nanogels. Our study is the first to introduce this linkage, which is generated from two vitamin B6 derivatives into a nanogel system. It is also the first to fabricate a rod-shaped nanogel system via simple solvent evaporation. Under acidic conditions, such as those encountered in the endosomes and lysosomes within inflammatory macrophage cells spread in the whole body, imine bonds are cleaved and release payloads. The nanogel polymers were successfully synthesized and characterized, and the formation and disappearance of the Schiff base under neutral and acidic conditions were also confirmed using Fourier transform infrared spectroscopy. Following curcumin encapsulation, the long, rod-shaped nanogels were able to rapidly internalize into macrophage cells in static or adhere to cells under the flows, release their payloads in the acid milieus, and, thus, mitigate curcumin degradation. Consequently, curcumin-loaded, rod-shaped nanogels displayed exceptional anti-inflammatory activity both in vitro and in vivo, by efficiently inhibiting pro-inflammatory mediator secretion. These results demonstrate the feasibility of our acid-labile, rod-shaped nanogels for the treatment of systemic inflammation.


Assuntos
Curcumina , Curcumina/farmacologia , Humanos , Inflamação/tratamento farmacológico , Nanogéis , Polietilenoglicóis , Polietilenoimina , Polímeros/química , Piridoxal , Piridoxamina , Bases de Schiff , Solventes , Vitaminas
7.
ACS Appl Mater Interfaces ; 13(46): 55358-55366, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34757712

RESUMO

In this study, proton-conducting behaviors of a cerium-based metal-organic framework (MOF), Ce-MOF-808, its zirconium-based isostructural MOF, and bimetallic MOFs with various Zr-to-Ce ratios are investigated. The significantly increased proton conductivity (σ) and decreased activation energy (Ea) are obtained by substituting Zr with Ce in the nodes of MOF-808. Ce-MOF-808 achieves a σ of 4.4 × 10-3 S/cm at 25 °C under 99% relative humidity and an Ea of 0.14 eV; this value is among the lowest-reported Ea of proton-conductive MOFs. Density functional theory calculations are utilized to probe the proton affinities of these MOFs. As the first study reporting the proton conduction in cerium-based MOFs, the finding here suggests that cerium-based MOFs should be a better platform for the design of proton conductors compared to the commonly reported zirconium-based MOFs in future studies on energy-related applications.

8.
Cancers (Basel) ; 13(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34359717

RESUMO

In this study, a graft copolymer, poly(N-(2-hydroxypropyl) methacrylamide dilactate)-co-(N-(2-hydroxypropyl) methacrylamide-co-histidine)-graft-poly(d,l-lactide), and a diblock copolymer, methoxy poly(ethylene glycol)-b-poly(d,l-lactide), were assembled into a mixed micellar system to encapsulate the anticancer drug doxorubicin (Dox). This mixed micellar system possesses the hydrophobic lactide segment of both copolymers, which reinforces its stability in physiological milieus; the histidine molecules appended on the graft copolymer provide the desired pH-responsive behavior to release Dox during internalization in cancer cells. The results demonstrate that the two copolymers were successfully prepared, and their ratios in the mixed micelles were optimized on the basis of the results of the stability tests. Under acidic conditions, the mixed micelles swell and are able to release their payloads. Therefore, the in vitro results indicate that the Dox in the mixed micelles is released effectively in response to the environmental pH of the mimetic internalization process, increasing cancer cells' sensitivity toward Dox. The mixed micelles display low cytotoxicity due to the degradability of the polymers. The in vivo images show that the high stability of the mixed micelles ensures a high tumor accumulation. This selective tumor accumulation results in an excellent inhibition of in vivo tumor growth and a high rate of apoptosis in cancerous tissues, with low toxicity. This highly stable, mixed micellar system with a pH-dependent drug release, which enables the precise delivery of drugs to the tumor lesions, is feasible to employ clinically in cancer therapy.

9.
Polymers (Basel) ; 13(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072925

RESUMO

In the treatment of cancers, small interfering ribonucleic acids (siRNAs) are delivered into cells to inhibit the oncogenic protein's expression; however, polyanions, hydrophilicity, and rapid degradations in blood, endosomal or secondary lysosomal degradation hamper clinal applications. In this study, we first synthesized and characterized two copolymers: methoxy poly(ethylene glycol)-b-poly(2-hydroxy methacrylate-ketal-pyridoxal) and methoxy poly(ethylene glycol)-b-poly(methacrylic acid-co-histidine). Afterwards, we assembled two polymers with the focal adhesion kinase (FAK) siRNA, forming polyplex-mixed micelles for the treatment of the human colon cancer cell line HCT116. In terms of the physiological condition, the cationic pyridoxal molecules that were conjugated on the copolymer with ketal bonds could electrostatically attract the siRNA. Additionally, the pyridoxal could form a hydrophobic core together with the hydrophobic deprotonated histidine molecules in the other copolymer and the hydrophilic polyethylene glycol (PEG) shell to protect the siRNA. In an acidic condition, the pyridoxal would be cleaved from the polymers due to the breakage of the ketal bonds and the histidine molecules can simultaneously be protonated, resulting in the endosome/lysosome escape effect. On the basis of our results, the two copolymers were successfully prepared and the pyridoxal derivatives were identified to be able to carry the siRNA and be cleavable by the copolymers in an acidic solution. Polyplex-mixed micelles were prepared, and the micellar structures were identified. The endosome escape behavior was observed using a confocal laser scanning microscopy (CLSM). The FAK expression was therefore reduced, and the cytotoxicity of siRNA toward human colon cancer cells was exhibited, rapidly in 24 h. This exceptional anticancer efficiency suggests the potential of the pH-sensitive polyplex-mixed micellar system in siRNA delivery.

11.
J Neuroinflammation ; 17(1): 210, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32664974

RESUMO

BACKGROUND: Excessive microglial activation is implicated in the pathogenesis of various age-related neurodegenerative diseases. In addition to neurons, brain-derived neurotrophic factor (BDNF) and its receptor TrkB are also expressed in microglia. However, the direct effect of BDNF on age-related microglial activation has rarely been investigated. METHODS: We began to address this question by examining the effect of age on microglial activation and the BDNF-TrkB pathway in mice. By using pharmacological and genetic approaches, the roles of BDNF and downstream signaling pathways in microglial activation and related neurotoxicity were examined in microglial cell line and primary microglial cells. RESULTS: We showed that microglial activation was evident in the brains of aged mice. The levels of BDNF and TrkB in microglia decreased with age and negatively correlated with their activation statuses in mice during aging. Interestingly, aging-related microglial activation could be reversed by chronic, subcutaneous perfusion of BDNF. Peripheral lipopolysaccharide (LPS) injection-induced microglial activation could be reduced by local supplement of BDNF, while shTrkB induced local microglial activation in naïve mice. In cultured microglial cell line and primary microglial cells, BDNF inhibited LPS-induced microglial activation, including morphological changes, activations of p38, JNK, and NF-кB, and productions of proinflammatory cytokines. These effects were blocked by shTrkB. BDNF induced activations of ErK and CREB which then competed with LPS-induced activation of NF-кB for binding to a common coactivator, CREB-binding protein. CONCLUSIONS: Decreasing BDNF-TrkB signaling during aging favors microglial activation, while upregulation BDNF signaling inhibits microglial activation via the TrkB-Erk-CREB pathway.


Assuntos
Envelhecimento/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Glicoproteínas de Membrana/metabolismo , Microglia/metabolismo , Proteínas Tirosina Quinases/metabolismo , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/patologia
12.
Cancers (Basel) ; 12(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098177

RESUMO

In this study, for the first time, we precisely assembled the poly-γ-benzyl-l-glutamate and an amphiphilic copolymer d-α-tocopherol polyethylene glycol succinate into a mixed micellar system for the embedment of the anticancer drug doxorubicin. Importantly, the intracellular drug-releasing behaviors could be controlled by changing the secondary structures of poly-γ-benzyl-l-glutamate via the precise regulation of the buffer's pH value. Under neutral conditions, the micellar architectures were stabilized by both α-helix secondary structures and the microcrystalline structures. Under acidic conditions (pH 4.0), the interior structures transformed into a coil state with a disordered alignment, inducing the release of the loaded drug. A remarkable cytotoxicity of the Dox-loaded mixed micelles was exhibited toward human lung cancer cells in vitro. The internalizing capability into the cancer cells, as well as the intracellular drug-releasing behaviors, were also identified and observed. The secondary structures containing Dox-loaded mixed micelles had an outstanding antitumor efficacy in human lung cancer A549 cells-bearing nude mice, while little toxicities occurred or interfered with the hepatic or renal functions after the treatments. Thus, these pH-tunable α-helix-containing mixed micelles are innovative and promising for controlled intracellular anticancer drug delivery.

13.
Acta Cardiol Sin ; 35(4): 402-411, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31371901

RESUMO

BACKGROUND: To investigate whether there is an increased risk of cardiovascular (CV) events in patients with diabetes associated with adding proton pump inhibitors (PPIs) to clopidogrel (CLO) therapy after bare-metal stent (BMS) deployment. METHODS: We used the National Health Insurance Research Database to conduct this retrospective cohort study. We enrolled 6,757 patients with diabetes who underwent BMS deployment and received CLO with/without PPIs for 90 days (6,243 in the CLO subgroup and 514 in the CLO plus PPI subgroup). The endpoints were acute coronary syndrome and re-admission for revascularization (PCI or coronary artery bypass graft surgery) after 3, 6, and 12 months. RESULTS: The patients who received CLO with PPIs had no significant increase in adverse CV events compared to those without PPIs within 1 year after BMS deployment [3-month hazard ratio (HR) = 0.87, 95% confidence interval (CI), 0.65-1.15; 6 months, HR = 0.95, 95% CI, 0.78-1.15; 1 year, HR = 0.60, 95% CI, 0.81-1.12]. CONCLUSIONS: In patients with diabetes undergoing BMS deployment, there was no evidence of an increased risk of CV events among concomitant users of CLO and PPIs. Our results indicate that the use of PPIs may not modify the protective effect of CLO after BMS implantation.

14.
Int J Mol Sci ; 19(11)2018 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-30453614

RESUMO

Curcumin has been proven to be a potent agent in colon cancer treatment. However, its hydrophobicity and low oral bioavailability hampered its clinical application. These limitations could be improved through appropriate formulations such as using polyelectrolyte complexes (PECs). PECs were self-assembled with polycations and polyanions in polar solvents. In this study, a novel pectin-type B gelatin PEC was developed for use in curcumin formulation. At pH 4.0, natural polyanions pectin and polycations type B gelatin spontaneously formed PECs in ethanol/water solution, whereas under mimetic gastrointestinal tract (GI tract) conditions, at pH 2.0 and 8.0, pectin and type B gelatin were electrically neutralized, and the PECs swelled to allow payload release. After being transferred to pH 7.0 condition, as in the colon environment, PECs were internalized into colon carcinomas. Thus, pectin-type B gelatin PECs were successfully prepared, and their constituent ratio and drug-loading process were also optimized. The optimum particle size of the PECs was 264.0 ± 3.1 nm and they could swell as the zeta potential was altered at either pH 2.0 or 8.0. The optimum drug content and loading efficiency were 40% and 53%, respectively. At pH 2.0, curcumin was rapidly released from curcumin-loaded PECs, whereas at pH 8.0, curcumin-loaded PECs showed a sustained-release of curcumin. The bare PECs showed very low toxicity toward human normal cells, whereas curcumin-loaded PECs, after incubation at pH 2.0 for 2 h and at pH 8.0 for 4 h, induced cell cycle arrest and exhibited cytotoxic effect to HCT116 human colon cancer cells, even though these loaded PECs were pretreated with mimetic GI tract conditions. Our pectin-type B gelatin PECs were shown to be a promising oral formulation for curcumin delivery in anticancer therapy.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos , Gelatina/química , Pectinas/química , Polieletrólitos/química , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Células HCT116 , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Eletricidade Estática
15.
PLoS One ; 13(7): e0200995, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30059550

RESUMO

BACKGROUND: Hip screening is the standard approach for the early detection of developmental dysplasia of the hip (DDH). However, there is a lack of evidence regarding the effects of national policy on early diagnosis and later surgical incidence. The purpose of this national study is to estimate DDH incidence in the Taiwanese population through a new diagnosis definition and to examine whether a health promotion policy could reduce surgeries for DDH. METHODS AND RESULTS: Six birth-year cohorts (2000-2005) were evaluated for DDH diagnosis and related surgeries using the database of the National Health Insurance Administration, which covers 99% of the population of Taiwan. Children with three or more sequential International Classification of Disease, Ninth Revision (ICD-9) diagnosis codes (754.3x) in the outpatient claim file or DDH-related surgeries were studied. The outcome of hip screening was evaluated with the ratio of early diagnosis (0-6 months) to late diagnosis (1-5 years) and the incidence of major surgeries for DDH. DDH incidence was 1.54 per thousand live births (2,255/1,462,539). After a hip screening promotion policy was implemented in 2002, ratios of early/late diagnosis increased from 1.06, 1.25, 1.38, and 1.5 to 1.75 for the years 2000 to 2005, respectively. Incidences of major surgery decreased from 0.41-0.47 per thousand before policy administration to 0.33-0.37 per thousand after policy administration. DISCUSSION: The DDH incidence of 1.54 per 1,000 in a geographically well-defined area offered epidemiological data for further studies in Asian populations. The results suggest that the health promotion policy is associated with an increase in early diagnosis and subsequently a decrease in surgeries for DDH.


Assuntos
Política de Saúde , Luxação Congênita de Quadril/diagnóstico , Luxação Congênita de Quadril/cirurgia , Pré-Escolar , Estudos de Coortes , Diagnóstico Precoce , Feminino , Luxação Congênita de Quadril/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino
16.
Int J Mol Sci ; 19(6)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848991

RESUMO

pH-sensitive polymer⁻liposomes can rapidly release their payloads. However, it is difficult to simultaneously achieve stability and pH-responsiveness in the polymer⁻liposomes. In this study, stable and pH-sensitive crosslinked polymer⁻liposomes were fabricated through electrostatic interactions. The pH-sensitive copolymer methoxy poly(ethylene glycol)-block-poly(methacrylic acid)-cholesterol (mPEG-b-P(MAAc)-chol) and crosslinking reagent poly(ethylene glycol) with end-capped with lysine (PEG-Lys2) were synthesized and characterized. At physiological conditions, the pH-sensitive copolymers were anionic and interacted electrostatically with the cationic crosslinker PEG-Lys2, forming the electrostatically-crosslinked polymer⁻liposomes and stabilizing the liposomal structure. At pH 5.0, the carboxylic groups in mPEG-b-P(MAAc)-chol were neutralized, and the liposomal structure was destroyed. The particle size of the crosslinked polymer⁻liposomes was approximately 140 nm and the polymer⁻liposomes were loaded with the anticancer drug doxorubicin. At pH 7.4, the crosslinked polymer⁻liposomes exhibited good stability with steady particle size and low drug leakage, even in the presence of fetal bovine serum. At pH 5.0, the architecture of the crosslinked polymer⁻liposomes was damaged following rapid drug release, as observed by using transmission electron microscopy and their apparent size variation. The crosslinked polymer⁻liposomes were pH-sensitive within the endosome and in the human breast cancer cells MDA-MB-231, as determined by using confocal laser scanning microscopy. The intracellular drug release profiles indicated cytotoxicity in cancer cells. These results indicated that the highly-stable and pH-sensitive electrostatically-crosslinked polymer⁻liposomes offered a potent drug-delivery system for use in anticancer therapies.


Assuntos
Antineoplásicos/química , Lipossomos/química , Polímeros/química , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Polietilenoglicóis/química
17.
Polymers (Basel) ; 9(6)2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970893

RESUMO

Multifunctional polymer nanoparticles have been developed for cancer treatment because they could be easily designed to target cancer cells and to enhance therapeutic efficacy according to cancer hallmarks. In this study, we synthesized a pH-sensitive polymer, poly(methacrylic acid-co-histidine/doxorubicin/biotin) (HBD) in which doxorubicin (DOX) was conjugated by a hydrazone bond to encapsulate an immunotherapy drug, imiquimod (IMQ), to form dual cancer-targeting and dual drug-loaded nanoparticles. At low pH, polymeric nanoparticles could disrupt and simultaneously release DOX and IMQ. Our experimental results show that the nanoparticles exhibited pH-dependent drug release behavior and had an ability to target cancer cells via biotin and protonated histidine.

18.
J Mater Chem B ; 5(29): 5870-5880, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264220

RESUMO

Combination therapy through simultaneous delivery of two or more therapeutic agents using nanocarriers has emerged as an advanced tactic for cancer treatment. To ensure that two therapeutic agents can be co-delivered and rapidly release their cargo in tumor cells, a biocompatible pH-sensitive copolymer, methoxy poly(ethylene glycol)-b-poly(hydroxypropyl methacrylamide-g-α-tocopheryl succinate-g-histidine) (abbreviated as PTH), was designed and synthesized. The PTH copolymers spontaneously self-assembled into micellar-type nanoparticles in aqueous solutions and are used for co-delivery of therapeutic agents, doxorubicin (Dox) and α-TOS. During micellization, π-π stacking occurred between Dox/α-TOS and imidazole rings of PTH copolymers inducing a regular and tight arrangement of copolymers and drugs to form rod-like micelles, thus efficiently increasing the drug loading and encapsulation efficiency. The micelles enabled the rapid release of both Dox and α-TOS when the pH decreased from 7.4 to 4.5. The protein adsorption assay revealed that low amounts of IgG and BSA were adsorbed on the micelles. In vivo biodistribution demonstrated that the micelles could largely accumulate in the tumor tissues. Furthermore, drug-loaded micelles treated with HCT116 cancer cells exhibited higher cytotoxicity than normal cells, which confirmed that α-TOS exhibited a synergy effect with Dox towards cancer cells, while no recognizable side effects were observed during the treatment from organ function tests.

19.
Reprod Biomed Online ; 33(4): 449-457, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27475652

RESUMO

The role of LH during ovarian stimulation remains uncertain. Previous studies defined the low LH group using a single LH measurement on a predefined day of stimulation possibly not reflecting the entire follicular phase. This study retrospectively collected data from 619 IVF/ICSI cycles with GnRH antagonist and recombinant FSH. The low LH group was defined as LH concentration ≤0.8 mIU/ml at any time during the cycle. Pregnancy results were compared between patients with one episode of low LH or more than two episodes of low LH (study group) and those without low LH (control group). There was no difference in fertilization rates between the two groups (67.5 ± 1.7% versus 68.8 ± 1.0%, respectively). The implantation rates (20.4% versus 25.2%), clinical pregnancy rates (43.9% versus 45.2%) and live-birth rates (LBR) (23.7% versus 30.4%) appeared lower in the study group, but the differences were not significant. In the study group, there were significantly increased early pregnancy loss rates (31.1% versus 16.3%, P = 0.012). The odds of early pregnancy loss increases by 1.55 fold for increased episodes of low serum LH (P = 0.029). Whether the adverse outcome is due to impaired oocyte quality or an endometrial component deserves further investigation.


Assuntos
Aborto Espontâneo/sangue , Fertilização in vitro/métodos , Hormônio Luteinizante/sangue , Indução da Ovulação , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos
20.
Biomacromolecules ; 17(9): 3040-7, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27536957

RESUMO

Cytosolic drug delivery, a major route in cancer therapy, is limited by the lack of efficient and safe endosomal escape techniques. Herein, we demonstrate a reactive oxygen species (ROS)-responsive micelle composed of methoxy polyethylene glycol-b-poly(diethyl sulfide) (mPEG-PS) copolymers which can induce specific endosome escape in cancer cells by changes in the hydrophobicity of copolymers. Owing to the more ROS levels in cancer cells than normal cells, the copolymers can be converted into more hydrophilic and insert into and destabilize the cancer intracellular endosome membrane after cellular uptake. More importantly, we show that acid-intolerant drugs successfully maintain their bioactivity and cause selective cytotoxicity for cancer cells over normal cells. Our results suggest that the endosomal escape induced by hydrophobic-hydrophilic exchange of copolymers has great potential to locally and efficiently deliver biological agents (e.g., proteins and genes) in the cancer cell cytosol.


Assuntos
Antioxidantes/farmacologia , Sistemas de Liberação de Medicamentos , Micelas , Neoplasias/tratamento farmacológico , Polímeros/química , Espécies Reativas de Oxigênio/metabolismo , alfa-Tocoferol/farmacologia , Animais , Antioxidantes/administração & dosagem , Citosol/metabolismo , Endossomos/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Polietilenoglicóis/química , Coelhos , Células Tumorais Cultivadas , alfa-Tocoferol/administração & dosagem
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