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1.
BMC Plant Biol ; 24(1): 325, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658813

RESUMO

BACKGROUND: With the dramatic uplift of the Qinghai-Tibet Plateau (QTP) and the increase in altitude in the Pliocene, the environment became dry and cold, thermophilous plants that originally inhabited ancient subtropical forest essentially disappeared. However, Quercus sect. Heterobalanus (QSH) have gradually become dominant or constructive species distributed on harsh sites in the Hengduan Mountains range in southeastern QTP, Southwest China. Ecological stoichiometry reveals the survival strategies plants adopt to adapt to changing environment by quantifying the proportions and relationships of elements in plants. Simultaneously, as the most sensitive organs of plants to their environment, the structure of leaves reflects of the long-term adaptability of plants to their surrounding environments. Therefore, ecological adaptation mechanisms related to ecological stoichiometry and leaf anatomical structure of QSH were explored. In this study, stoichiometric characteristics were determined by measuring leaf carbon (C), nitrogen (N), and phosphorus (P) contents, and morphological adaptations were determined by examining leaf anatomical traits with microscopy. RESULTS: Different QSH life forms and species had different nutrient allocation strategies. Leaves of QSH plants had higher C and P and lower N contents and higher N and lower P utilization efficiencies. According to an N: P ratio threshold, the growth of QSH species was limited by N, except that of Q. aquifolioides and Q. longispica, which was limited by both N and P. Although stoichiometric homeostasis of C, N, and P and C: N, C: P, and N: P ratios differed slightly across life forms and species, the overall degree of homeostasis was strong, with strictly homeostatic, homeostatic, and weakly homeostatic regulation. In addition, QSH leaves had compound epidermis, thick cuticle, developed palisade tissue and spongy tissue. However, leaves were relatively thin overall, possibly due to leaf leathering and lignification, which is strategy to resist stress from UV radiation, drought, and frost. Furthermore, contents of C, N, and P and stoichiometric ratios were significantly correlated with leaf anatomical traits. CONCLUSIONS: QSH adapt to the plateau environment by adjusting the content and utilization efficiencies of C, N, and P elements. Strong stoichiometric homeostasis of QSH was likely a strategy to mitigate nutrient limitation. The unique leaf structure of the compound epidermis, thick cuticle, well-developed palisade tissue and spongy tissue is another adaptive mechanism for QSH to survive in the plateau environment. The anatomical adaptations and nutrient utilization strategies of QSH may have coevolved during long-term succession over millions of years.


Assuntos
Adaptação Fisiológica , Carbono , Nitrogênio , Fósforo , Folhas de Planta , Quercus , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Quercus/anatomia & histologia , Quercus/fisiologia , Fósforo/metabolismo , Nitrogênio/metabolismo , Tibet , Carbono/metabolismo , China , Ecossistema
2.
Adv Sci (Weinh) ; 11(17): e2400862, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408138

RESUMO

Hematoma, a risk factor of implant-associated infections (IAIs), creates a Fe-rich environment following implantation, which proliferates the growth of pathogenic bacteria. Fe metabolism is a major vulnerability for pathogens and is crucial for several fundamental physiological processes. Herein, a deferiprone (DFP)-loaded layered double hydroxide (LDH)-based nanomedicine (DFP@Ga-LDH) that targets the Fe-rich environments of IAIs is reported. In response to acidic changes at the infection site, DFP@Ga-LDH systematically interferes with bacterial Fe metabolism via the substitution of Ga3+ and Fe scavenging by DFP. DFP@Ga-LDH effectively reverses the Fe/Ga ratio in Pseudomonas aeruginosa, causing comprehensive interference in various Fe-associated targets, including transcription and substance metabolism. In addition to its favorable antibacterial properties, DFP@Ga-LDH functions as a nano-adjuvant capable of delaying the emergence of antibiotic resistance. Accordingly, DFP@Ga-LDH is loaded with a siderophore antibiotic (cefiderocol, Cefi) to achieve the antibacterial nanodrug DFP@Ga-LDH-Cefi. Antimicrobial and biosafety efficacies of DFP@Ga-LDH-Cefi are validated using ex vivo human skin and mouse IAI models. The pivotal role of the hematoma-created Fe-rich environment of IAIs is highlighted, and a nanoplatform that efficiently interferes with bacterial Fe metabolism is developed. The findings of the study provide promising guidance for future research on the exploration of nano-adjuvants as antibacterial agents.


Assuntos
Antibacterianos , Biofilmes , Ferro , Infecções Relacionadas à Prótese , Pseudomonas aeruginosa , Biofilmes/efeitos dos fármacos , Camundongos , Ferro/metabolismo , Animais , Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/microbiologia , Deferiprona/farmacologia , Modelos Animais de Doenças , Cefiderocol , Infecções por Pseudomonas/tratamento farmacológico , Humanos , Nanomedicina/métodos
3.
Adv Healthc Mater ; 13(9): e2303361, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38115718

RESUMO

Combining hyperthermic intraperitoneal chemotherapy with cytoreductive surgery is the main treatment modality for peritoneal metastatic (PM) carcinoma despite the off-target effects of chemotherapy drugs and the ineluctable side effects of total abdominal heating. Herein, a laser-integrated magnetic actuation system that actively delivers doxorubicin (DOX)-grafted magnetic nanorobot collectives to the tumor site in model mice for local hyperthermia and chemotherapy is reported. With intraluminal movements controlled by a torque-force hybrid magnetic field, these magnetic nanorobots gather at a fixed point coinciding with the position of the localization laser, moving upward against gravity over a long distance and targeting tumor sites under ultrasound imaging guidance. Because aggregation enhances the photothermal effect, controlled local DOX release is achieved under near-infrared laser irradiation. The targeted on-demand photothermal therapy of multiple PM carcinomas while minimizing off-target tissue damage is demonstrated. Additionally, a localization/treatment dual-functional laser-integrated magnetic actuation system is developed and validated in vivo, offering a potentially clinically feasible drug delivery strategy for targeting PM and other intraluminal tumors.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias Peritoneais , Animais , Camundongos , Neoplasias Peritoneais/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Doxorrubicina/farmacologia , Hipertermia Induzida/métodos , Fototerapia/métodos , Raios Infravermelhos
4.
Adv Healthc Mater ; 12(10): e2202562, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36610060

RESUMO

Ferroptosis-based treatment strategies display the potential to suppress some malignant tumors with intrinsic apoptosis resistance. However, current related cancer treatments are still hampered by insufficient intracellular reactive oxygen species (ROS) levels and Fe2+ contents, posing considerable challenges for their clinical translation. Herein, an intracellular acid-biodegradable iridium-coordinated nanosheets (Ir-Hemin) with sonodynamic therapy (SDT) properties to effectively induce ferroptosis in tumor cells through multiple regulatory pathways are proposed. Under ultrasound (US) irradiation, Ir-Hemin nanosheets act as nanosonosensitizers to effectively generate ROS, subsequently causing the accumulation of lipid peroxides (LPO) and inducing ferroptotic cell death. Furthermore, these Ir-Hemin nanosheets decompose quickly to release hemin and Ir(IV), which deplete intracellular glutathione (GSH) to deactivate the enzyme glutathione peroxidase 4 (GPX4) and initiate the ferroptosis pathway. Specifically, the released hemin enables heme oxygenase 1 (HO-1) upregulation for endogenous ferrous ion supplementation, which compensates for the toxicity concerns brought about by the large uptake of exogenous iron. Surprisingly, Ir-Hemin nanosheets exhibit high tumor accumulation and trigger effective ferroptosis for tumor therapy. These Ir-Hemin nanosheets display pronounced synergistic anticancer efficacy under US stimulation both in vitro and in vivo, providing a strong rationale for the application of ferroptosis in cancer treatment.


Assuntos
Irídio , Neoplasias , Humanos , Irídio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Hemina/farmacologia , Hemina/uso terapêutico , Morte Celular , Apoptose , Neoplasias/tratamento farmacológico , Glutationa/metabolismo
5.
Int J Biol Macromol ; 216: 629-642, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35810853

RESUMO

In the present study, clove essential oil (CEO) Pickering emulsions were stabilized by octadecylamine-modified carboxymethyl curdlan (CMCD-ODA) at different pH values. The droplet size and negatively charged zeta potential of the CMCD-ODA emulsions decreased as the pH increased from 3.0 to 11.0. Rheology results indicated that the CMCD-ODA polymer/emulsion prepared at pH 5.0 showed higher apparent viscosity and viscoelasticity than other pH conditions, which might prevent droplets from flocculating. The Pickering emulsions obtained at pH 5.0 were spherical droplets with a uniform size distribution and a mean diameter of 9.54 µm, and they exhibited excellent stability during 28 days of storage. The morphological structures of the emulsions investigated by confocal laser scanning microscopy and scanning electron microscopy indicated that the CMCD-ODA Pickering emulsion obtained at pH 5.0 was stabilized by loading amphiphilic CMCD-ODA polymer around the spherical oil droplets and forming a weak gel network structure. The CEO-loaded CMCD-ODA emulsions had higher antioxidant capacity than free CEO after 28 days of storage at pH 5.0. Given the good emulsion stability, antioxidant activity, and great antibacterial effect, the CEO-loaded carboxymethyl curdlan Pickering emulsion has promising applications in food, cosmetic, and biomedicine industries.


Assuntos
Óleos Voláteis , Syzygium , Disponibilidade Biológica , Óleo de Cravo , Emulsões/química , Óleos Voláteis/química , Tamanho da Partícula , Polímeros , beta-Glucanas
6.
J Nanobiotechnology ; 19(1): 126, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947395

RESUMO

BACKGROUND: Photothermal therapy (PTT), involving application of localized hyperthermia to kill cancer cells, has attracted wide attention in cancer therapy. The production of reactive oxygen species (ROS) during PTT may cause irreversible damage to healthy tissues around the tumor. Simultaneously, hyperthermia can stimulate inflammatory response, thus promoting tumor recurrence and metastasis. Therefore, it is of paramount importance to reduce the undesired side effects for further development of PTT. RESULTS: Using a hydrothermal method, spherical Prussian blue nanoparticles (PBs) with uniform size were prepared. The PBs exhibited good dispersion and stability in saline with an average hydrodynamic size of 110 nm. The prepared PBs had a high photothermal conversion efficiency and photothermal stability. The PBs showed intrinsic ROS scavenging properties in vitro. Antioxidant and anti-inflammatory effects of PBs were also observed in vivo. Assessment of toxicity and endoplasmic reticulum stress-inducing ability showed that PBs did not induce an inflammatory response. Tissues of major organs of mice stained with hematoxylin-eosin showed no significant damage, indicating good biocompatibility and safety of PBs. CONCLUSION: The designed single-component PBs with intrinsic ROS scavenging and anti-inflammatory properties could avoid inflammatory response and heat stress-induced ROS during PTT. Thus, further research on PBs is worthwhile to achieve their clinical translation and promote the development of PTT.


Assuntos
Ferrocianetos/química , Ferrocianetos/farmacologia , Hipertermia Induzida/métodos , Hipertermia/tratamento farmacológico , Nanopartículas/química , Nanopartículas/uso terapêutico , Terapia Fototérmica/métodos , Animais , Neoplasias da Mama , Feminino , Hipertermia/patologia , Inflamação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fármacos Fotossensibilizantes/farmacologia , Células RAW 264.7 , Espécies Reativas de Oxigênio
7.
Acta Biomater ; 126: 408-420, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33731303

RESUMO

The combination of chemotherapy and photothermal therapy (PTT) into a single formulation has attracted increasing attention as a strategy for enhancing cancer treatment. Here, hollow mesoporous silica nanoparticles (HMSNs) were used as a base carrier material, loaded with the anti-cancer drug doxorubicin (DOX), and surface functionalized with chitosan (CS) and copper sulfide (CuS) nanodots to give HMSNs-CS-DOX@CuS. In this formulation, the CuS dots act as gatekeepers to seal the surface pores of the HMSNs, preventing a burst release of DOX into the systemic circulation. S-S bonds connect the CuS dots to the HMSNs; these are selectively cleaved under the reducing microenvironment of the tumor, permitting targeted drug release. This, coupled with the PTT properties of CuS, results in a potent chemo/PTT platform. The HMSNs-CS-DOX@CuS nanoparticles have a uniform size (150 ± 13 nm), potent photothermal properties (η = 36.4 %), and tumor-targeted and near infrared (NIR) laser irradiation-triggered DOX release. In vitro and in vivo experimental results confirmed that the material has good biocompatibility, but is effectively taken up by cancer cells. Moreover, the CuS nanodots permit simultaneous thermal/photoacoustic dual-modality imaging. Treatment with HMSNs-CS-DOX@CuS and NIR irradiation caused extensive apoptosis in cancer cells both in vitro and in vivo, and could dramatically extend the lifetimes of animals in a murine breast cancer model. The system developed in this work therefore merits further investigation as a potential nanotheranostic platform for cancer treatment. STATEMENT OF SIGNIFICANCE: Conventional cancer chemotherapy is accompanied by unavoidable off-target toxicity. Combination therapies, which can ameliorate these issues, are attracting significant attention. Here, the anticancer drug doxorubicin (DOX) was encapsulated in the central cavity of chitosan (CS)-modified hollow mesoporous silica nanoparticles (HMSNs). The prepared system can target drug release to the tumor microenvironment. When exposed to near infrared laser (NIR) irradiation, CuS nanodots located at the surface pores of the HMSNs generate energy, accelerating drug release. In addition, a systematic in vitro and in vivo evaluation confirmed the HMSNs-CS-DOX@CuS platform to give highly effective synergistic chemotherapeutic-photothermal therapy and have effective thermal/photoacoustic dual-imaging properties. This work may open up a new avenue for NIR-enhanced synergistic therapy with simultaneous thermal/photoacoustic dual imaging.


Assuntos
Antineoplásicos , Neoplasias da Mama , Quitosana , Nanopartículas , Animais , Antineoplásicos/farmacologia , Cobre/farmacologia , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Camundongos , Fototerapia , Medicina de Precisão , Dióxido de Silício , Sulfetos , Microambiente Tumoral
8.
Nanoscale ; 12(27): 14739-14750, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32626854

RESUMO

In this work, an innovative boron-based multifunctional nanoplatform was developed for synergistic chemotherapy/low temperature photothermal therapy (PTT). This platform is functionalized with a cRGD peptide to allow the targeting of αvß3 integrin, which is over-expressed in the cells of tumors. The nanoparticles were further loaded with the chemotherapeutic drug doxorubicin (DOX) and a heat shock protein inhibitor (17AAG), and high loading capacities for both DOX (603 mg g-1 B-PEG-cRGD) and 17AAG (417 mg g-1) were obtained. The resultant DOX-17AAG@B-PEG-cRGD system shows both pH-controlled and near-infrared (NIR)-induced DOX and 17AAG release. It also provides significantly enhanced cellular uptake in cancerous cells over healthy cells. The presence of 17AAG allows low-temperature PTT to be combined with chemotherapy with DOX, resulting in highly effective anti-cancer activity. This has been confirmed by both in vitro assays and using an in vivo murine cancer model. It is expected that such a multifunctional nanoplatform can serve as a promising candidate for cancer therapy.


Assuntos
Nanopartículas , Fototerapia , Animais , Boro , Doxorrubicina/farmacologia , Camundongos , Terapia Fototérmica , Temperatura
9.
Eur J Cancer ; 132: 35-42, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32325418

RESUMO

BACKGROUND: Angiogenesis is critical for tumour growth and metastasis. Dual inhibition of vascular endothelial growth factors and platelet-derived growth factor receptors suppresses angiogenesis. This expansion cohort of a phase I study targeted angiogenesis with sorafenib, bevacizumab and low-dose cyclophosphamide in children and young adults with recurrent solid tumours. METHODS: An expansion cohort including patients with refractory or recurrent solid tumours was enrolled and received bevacizumab (15 mg/kg IV, day 1), sorafenib (90 mg/m2 po twice daily, days 1-21) and low-dose cyclophosphamide (50 mg/m2 po daily, days 1-21). Each course was 21 days. Toxicities were assessed using Common Terminology Criteria for Adverse Events, v3.0, and responses were evaluated by Response Evaluation Criteria in Solid Tumors criteria. Serial bevacizumab pharmacokinetic (PK) studies were performed during course 1. RESULTS: Twenty-four patients (15 males; median age 14.5 yrs; range 1-22 yr) received a median of 6 courses (range 1-18). Twelve patients had a bone or soft tissue sarcoma. The most common grade III/IV non-haematologic toxicities were hypertension (N = 4), hand/foot rash (N = 3) and elevated lipase (N = 3). The most common grade III/IV haematologic toxicities were neutropenia (N = 7) and lymphopenia (N = 17). Three patients (2 synovial sarcoma, 1 rhabdoid tumour) achieved a partial response and 18 had stable disease. The progression-free survival at 3 and 6 months were 78.1% (95% confidence interval [CI] 60.6-95.6%) and 54% (95% CI 30.2-78.2%), respectively. Bevacizumab PKs in 15 patients was similar to published adult PK results. CONCLUSIONS: Intravenous bevacizumab combined with oral sorafenib and low-dose cyclophosphamide was tolerated and demonstrated promising activity in a subset of childhood solid tumours.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Terapia de Salvação , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Bevacizumab/administração & dosagem , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Feminino , Seguimentos , Humanos , Lactente , Masculino , Dose Máxima Tolerável , Recidiva Local de Neoplasia/patologia , Neoplasias/patologia , Prognóstico , Sorafenibe/administração & dosagem , Taxa de Sobrevida , Distribuição Tecidual , Adulto Jovem
10.
Colloids Surf B Biointerfaces ; 185: 110585, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683203

RESUMO

Synergistic tumor treatment has recently attracted more and more attention due to its remarkable therapeutic effect. Herein, a multifunctional drug delivery system based on hyaluronic acid (HA) targeted dual stimulation responsive MoS2 nanosheets (HA-PEI-LA-MoS2-PEG, HPMP) for active interaction with CD44 receptor positive MCF-7 cells is reported. Melanin (Mel), a new type of photothermal agent and doxorubicin (DOX) are both loaded onto the HPMP nanocomposite and can be released by mild acid or hyperthermia. The prepared HPMP nanocomposite has a uniform hydrodynamic diameter (104 nm), a high drug loading (944.3 mg.g-1 HPMP), a remarkable photothermal effect (photothermal conversion efficiency: 55.3%) and excellent biocompatibility. The DOX release from HPMP@(DOX/Mel) can be precisely controlled by the dual stimuli of utilizing the acidic environment in the tumor cells and external laser irradiation. Meanwhile, loading of Mel onto the surface can enhance the photothermal effect of the MoS2 nanosheets. In vitro experiments showed that the HPMP@(DOX/Mel) nanoplatform could efficiently deliver DOX into MCF-7 cells and demonstrated enhanced cytotoxicity compared to that of the non-targeted nanoplatform. In vivo experiments in a breast cancer model of nude mice further confirmed that the HPMP@(DOX/Mel) significantly inhibited tumor growth under near infrared (NIR) laser irradiation, which is superior to any single therapy. In summary, this flexible nanoplatform, based on multi-faceted loaded MoS2 nanosheets, exhibits considerable potential for efficient pH/NIR-responsive targeted drug delivery and chemo-photothermal synergistic tumor therapy.


Assuntos
Neoplasias da Mama/terapia , Dissulfetos/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Hipertermia Induzida , Molibdênio/química , Nanocompostos/química , Fototerapia , Animais , Antibióticos Antineoplásicos/farmacologia , Apoptose , Neoplasias da Mama/patologia , Proliferação de Células , Doxorrubicina/química , Liberação Controlada de Fármacos , Feminino , Humanos , Raios Infravermelhos , Camundongos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Int J Biol Macromol ; 155: 1342-1349, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730980

RESUMO

Polysialic acid (PSA), an acidic polysaccharide usually exists as a double-chain structure on cell adhesion molecules in vertebrates. The available PSA produced from Escherichia coli fermentation, however, is monochain PSA. In this work, a biomimetic biantenna type PSA (biPSA) was synthesized in vitro under mild conditions, and the terminal nonreducing ends of sialic acid residue were retained. The structure of biPSA was characterized through infrared spectroscopy, and NMR, and the double-chain structure of biPSA was confirmed by the doubled molecular weight and particle size of biPSA. Analysis through circular dichroism, isothermal titration calorimetry, and thermostability experiments revealed that the obtained biPSA was more stable in aqueous solution than PSA, especially after complexation with Ca2+, which increased the variation in enthalpy and entropy. However, the addition of Cu2+ had a negligible effect on configuration of PSA and biPSA. The addition of Ca2+ promoted cell proliferation in a culture of microglia BV-2 cells with biPSA in medium. By contrast, the addition of Cu2+ had toxic effects. Supplementation with biPSA can maintain cell viability for a longer period than supplementation with monochain PSA. This work indicates that biPSA is a potential substitute for monochain PSA in practical applications.


Assuntos
Materiais Biomiméticos/química , Cálcio/farmacologia , Polissacarídeos/química , Ácidos Siálicos/química , Animais , Calorimetria , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Cobre/farmacologia , Meios de Cultura , Escherichia coli/metabolismo , Fermentação , Peso Molecular , Tamanho da Partícula , Polissacarídeos/biossíntese , Ácidos Siálicos/biossíntese , Vertebrados
12.
Int J Nanomedicine ; 14: 7141-7153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564870

RESUMO

BACKGROUND: Theranostics, elaborately integrating both therapeutic and diagnostic functions into a nanoplatform holds great potential for precision cancer medicine. METHODS: Herein, a biodegradable theranostic nanoplatform with hyperthermia-induced bubble ability for highly efficient ultrasound (US) imaging-guided chemo-photothermal therapy of breast tumors was developed. The prepared nanoparticles consisted of polydopamine (PDA)-modified hollow mesoporous organosilica nanoparticles (HMONs) with approximately 75 nm in diameter for doxorubicin (DOX) loading and perfluoropentane (PFP) filling. In addition, the pH-sensitive PDA coating served as both gatekeeper controlling DOX release and photothermal agent for inducing hyperthermia. RESULTS: Such nanoplatform (PDA@HMONs-DOX/PFP, PHDP) provides efficient loading (328 mg/g) and controllable stimuli-responsive release of DOX for chemotherapy. The incorporated disulfide bonds in the framework of HMONs endowed nanoparticles with intrinsic glutathione-responsive biodegradability and improved biocompatibility. Benefiting from the hyperthermia upon an 808-nm laser irradiation of PDA, the liquid-gas phase transition of the loaded PFP was induced, resulting in the generation of the nanobubbles, followed by the coalescence into microbubbles. This conversation could enhance the tumor cell uptake of nanoparticles, as well as intensify the US imaging signals. In addition, a synergistic therapeutic effect of our fabricated nanoplatform on cells/tumor growth effect has been systematically evaluated both in vitro and in vivo. CONCLUSION: Therefore, such "all-in-one" PHDP nanoparticles with satisfactory biocompatibility and biodegradability, hyperthermia-induced bubble ability and simultaneous US imaging performance hold great potential for cancer nanotheranostics.


Assuntos
Hipertermia Induzida , Microbolhas , Nanopartículas/química , Fototerapia , Nanomedicina Teranóstica , Ultrassonografia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Endocitose/efeitos dos fármacos , Feminino , Humanos , Indóis/química , Cinética , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Polímeros/química , Distribuição Tecidual/efeitos dos fármacos
13.
World J Microbiol Biotechnol ; 35(7): 113, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289918

RESUMO

Camellia taliensis (W. W. Smith) Melchior is a wild tea plant endemic from the west and southwest of Yunnan province of China to the north of Myanmar and is used commonly to produce tea by the local people of its growing areas. Its chemical constituents are closely related to those of C. sinensis var. assamica, a widely cultivated tea plant. In this study, the α diversity and phylogeny of endophytic fungi in the branches of C. taliensis were explored for the first time. A total of 160 fungal strains were obtained and grouped into 42 species from 29 genera, which were identified based on rDNA internal transcribed spacer sequence analysis. Diversity analysis showed that the endophytic fungal community of the branches of C. taliensis had high species richness S (42), Margalef index D' (8.0785), Shannon-Wiener index H' (2.8494), Simpson diversity index DS (0.8891), PIE index (0.8947) and evenness Pielou index J (0.7623) but a low dominant index λ (0.1109). By contrast, that in the branches of C. taliensis had abundant species and high species evenness. Diaporthe tectonigena, Acrocalymma sp. and Colletotrichum magnisporum were the dominant endophytic fungi. The phylogenetic tree was established by maximum parsimony analysis, and the 11 orders observed for endophytic fungi belonging to Ascomycota and Basidiomycota were grouped into 4 classes.


Assuntos
Camellia/microbiologia , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/isolamento & purificação , Filogenia , Chá , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/isolamento & purificação , Biodiversidade , China , Análise por Conglomerados , DNA Ribossômico/genética , Endófitos/genética , Fungos/genética , Mianmar , Análise de Sequência
14.
Bioprocess Biosyst Eng ; 42(5): 777-784, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30741355

RESUMO

Rhamnolipids (RLs) are anionic biosurfactants with great application potential. This study explored the possibility of producing RLs from cooking oil fume condensates (COFCs) collected from range hoods. A mutant of Pseudomonas aeruginosa AB93066 was obtained and used to produce RLs from COFCs as a substrate. RL yields in a 7-L fermenter reached 12.3 g/L, and MALDI-TOF MS showed that Rha2-C10-C10 and Rha-C10-C10 are the most abundant (39.6% and 26.4%, respectively) RL components. The critical micellar concentration (CMC) of the RLs was 45.0 mg/L and the surface tension of water decreased from 60.5 to 25.3 mN/m. Using six kinds of common hydrocarbons as indices, the emulsification coefficients of the RLs obtained were found to exceed 60%; in particular, the emulsification coefficient for benzene was 80.3%. COFCs provide an inexpensive alternative as a substrate for RL production, and the synthetic process is relatively harmless and economical.


Assuntos
Culinária , Glicolipídeos/biossíntese , Óleos de Plantas , Pseudomonas aeruginosa/crescimento & desenvolvimento , Reciclagem/métodos
15.
J Colloid Interface Sci ; 539: 433-441, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30599399

RESUMO

Molybdenum disulfide (MoS2)-based drug delivery systems have shown considerable potential in cancer nanomedicines. In this work, a multifunctional nanoplatform comprising MoS2 nanosheets decorated with copper sulfide (CuS) and further functionalized with polyethylene glycol (PEG) is reported. The resultant material has a particle size of approximately 115 nm, and can be loaded with doxorubicin (DOX) to a loading capacity of 162.3 mg DOX per g of carrier. Drug release is triggered by two stimuli (near infrared (NIR) irradiation and pH), and the carrier is shown to have excellent colloidal stability. The presence of both MoS2 and CuS leads to very high photothermal conversion efficiency (higher than with MoS2 alone). In vitro experiments revealed that the blank CuS-MoS2-SH-PEG carrier is biocompatible, but that the synergistic application of chemo-photothermal therapy (in the form of CuS-MoS2-SH-PEG loaded with DOX and NIR irradiation) led to greater cell death than either chemotherapy (CuS-MoS2-SH-PEG(DOX) but no NIR) or photothermal therapy (CuS-MoS2-SH-PEG with NIR). A cellular uptake study demonstrated that the nanoplatform can efficiently enter tumor cells, and that uptake is enhanced when NIR is applied. Overall, the functionalized MoS2 material developed in this work exhibits great potential as an efficient system for dual responsive drug delivery and synergistic chemo-photothermal therapy. The route employed in our work thus provides a strategy to enhance photothermal efficacy for transition metal dichalcogenide drug delivery systems.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Cobre/química , Dissulfetos/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Molibdênio/química , Fototerapia , Antibióticos Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Nanopartículas/química , Tamanho da Partícula , Polietilenoglicóis/química , Relação Estrutura-Atividade , Propriedades de Superfície
16.
ACS Appl Mater Interfaces ; 10(49): 42115-42126, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30462492

RESUMO

Noninvasive physical treatment with relatively low intensity stimulation and the development of highly efficient anticancer medical strategy are still desirable for cancer therapy. Herein a versatile, biodegradable, hollow mesoporous organosilica nanocapsule (HMONs) nanoplatform that is capped by the gemcitabine (Gem) molecule through a pH-sensitive acetal covalent bond is designed. The fabricated nanocapsule exhibits desirable small molecule release at the tumor tissues/cell sites and shows a reduced risk for drug accumulation. After loading indocyanine green (ICG), the heat-shock protein 90 (Hsp 90) inhibitor, and 17AAG and modification with polyethylene glycol (NH2-PEG), the resulting ICG-17AAG@HMONs-Gem-PEG exhibited a precisely controlled release of ICG and 17AAG and low-temperature photothermal therapy (PTT) (∼41 °C) with excellent tumor destruction efficacy. In addition, ICG loading conferred the nanoplatform with near-infrared fluorescence imaging (FL) and photoaccoustic (PA) imaging capability. In short, this work not only presents a smart drug self-controlled nanoplatform with pH-responsive payload release and theranostic performance but also provides an outstanding low-temperature PTT strategy, which is highly valid in the inhibition of cancer cells with minimal damage to the organism. Therefore, this research provides a paradigm that has a chemodrug-gated HMONs-based theranostic nanoplatform with intrinsic biodegradability, multimodal imaging capacity, high low-temperature PTT/chemotherapy efficacy, and reduced systemic toxicity.


Assuntos
Doxorrubicina , Hipertermia Induzida , Verde de Indocianina , Nanocápsulas , Compostos de Organossilício , Fototerapia , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacocinética , Verde de Indocianina/farmacologia , Camundongos , Camundongos Nus , Nanocápsulas/química , Nanocápsulas/uso terapêutico , Compostos de Organossilício/química , Compostos de Organossilício/farmacocinética , Compostos de Organossilício/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia
17.
J Laparoendosc Adv Surg Tech A ; 27(2): 206-210, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27992299

RESUMO

BACKGROUND: Laparoscopy offers many benefits to splenectomy, such as reduced incisional pain and shortened hospital duration. The purpose of this study is to evaluate procedural and outcome differences between multiport (MP) and reduced port (RP) splenectomy when utilized to treat children. PATIENTS AND METHODS: An institutional review board approved retrospective analysis of all consecutive laparoscopic total splenectomies performed at a single institution between January 2010 and October 2015 was conducted. We evaluated demographics, surgical technique, instance of conversion, operative duration, estimated blood loss, need for intraoperative blood transfusion, postoperative length of stay, time to full feeds, complications, and follow-up duration. RESULTS: Over a 5-year period, 66 patients less than 20 years of age underwent laparoscopic total splenectomy. RP splenectomy was attempted in 14 patients. The remaining 52 were MP operations. Populations were comparable with regard to demographics. Preoperative splenic volumes (mL) were greater in the RP population (median [IQR]: 1377 [747-1508] versus 452 [242-710], P = .039). RP splenectomy demonstrated no difference compared to MP splenectomy in operative time (153 versus 138 minutes, P = .360), estimated blood loss (120 versus 154 mL, P = .634), or percent of cases requiring intraoperative blood transfusion (14 versus 23, P = .716). By the first postoperative day, 57% of RP and 17% of MP patients could be discharged (P = .005). Thirty-day readmission rates were similar, at 7% for RP and 8% for MP operations. Fever was the indication for all readmissions. Mean duration of follow-up is 28 months for MP and 13 months for RP cases. CONCLUSION: A reduced number of ports can be safely utilized for total splenectomy in pediatric patients without increasing procedural duration or need for intraoperative blood transfusion. In addition, rate of discharge on the first postoperative day was significantly higher in the RP splenectomy group.


Assuntos
Laparoscopia/métodos , Baço/cirurgia , Esplenectomia/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Laparoscopia/efeitos adversos , Tempo de Internação , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Esplenectomia/efeitos adversos , Resultado do Tratamento
18.
Pediatr Blood Cancer ; 64(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27786412

RESUMO

VS-4718, a novel inhibitor of focal adhesion kinase (FAK), was tested against the Pediatric Preclinical Testing Program's (PPTP's) in vitro cell line panel and showed a median relative IC50 of 1.22 µM. VS-4718 was tested in vivo against the PPTP xenograft models using a dose of 50 mg/kg administered by the oral route twice daily for 21 days. VS-4718 induced significant differences in an event-free survival distribution compared with control in 18 of 36 of the evaluable solid tumor xenografts and in 0 of 8 acute lymphoblastic leukemia (ALL) xenografts, but no xenograft lines showed tumor regression. Future plans include further evaluation of the role of FAK inhibition in combination with ABL kinase inhibitors for Ph+ ALL.


Assuntos
Aminopiridinas/farmacologia , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Neoplasias Experimentais/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Neoplasias Experimentais/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Pediatr Surg ; 50(9): 1484-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25783402

RESUMO

PURPOSE: Antiangiogenic agents show significant antitumor activity against various tumor types. In a study evaluating the combination of sorafenib, bevacizumab, and low-dose cyclophosphamide in children with solid tumors, an unexpectedly high incidence of pneumothorax was observed. We evaluated patient characteristics and risk factors for the development of pneumothorax in patients receiving this therapy. PATIENTS AND METHODS: Demographics, clinical course, and radiographic data of 44 patients treated with sorafenib, bevacizumab and cyclophosphamide were reviewed. Risk factors associated with the development of pneumothorax were analyzed. RESULTS: Pneumothorax likely related to study therapy developed in 11 of 44 (25%) patients of whom 33 had pulmonary abnormalities. Median age of patients was 14.7 years (range, 1.08-24.5). Histologies associated with pneumothorax included rhabdoid tumor, synovial sarcoma, osteosarcoma, Ewing sarcoma, Wilms tumor, and renal cell carcinoma. Cavitation of pulmonary nodules in response to therapy was associated with pneumothorax development (P<0.001). Median time from start of therapy to development of pneumothorax was 5.7 weeks (range, 2.4-31). CONCLUSION: The development of cavitary pulmonary nodules in response to therapy is a risk factor for pneumothorax. As pneumothorax is a potentially life-threatening complication of antiangiogenic therapy in children with solid tumors, its risk needs to be evaluated when considering this therapy.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Neoplasias Ósseas/tratamento farmacológico , Pneumotórax/induzido quimicamente , Sarcoma de Ewing/tratamento farmacológico , Sarcoma Sinovial/tratamento farmacológico , Tumor de Wilms/tratamento farmacológico , Adolescente , Adulto , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/efeitos adversos , Bevacizumab/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Niacinamida/uso terapêutico , Osteossarcoma/tratamento farmacológico , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/uso terapêutico , Pneumotórax/diagnóstico , Sorafenibe , Adulto Jovem
20.
Pediatr Blood Cancer ; 62(1): 91-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25263539

RESUMO

BACKGROUND: BMN 673 is a potent inhibitor of poly-ADP ribose polymerase (PARP) that is in clinical testing with a primary focus on BRCA-mutated cancers. BMN 673 is active both through inhibiting PARP catalytic activity and by tightly trapping PARP to DNA at sites of single strand breaks. PROCEDURE: BMN 673 was tested in vitro at concentrations ranging from 0.1 nM to 1 µM and in vivo at a daily dose of 0.33 mg/kg administered orally twice daily (Mon-Fri) and once daily on weekends (solid tumors) for 28 days. RESULTS: The median relative IC50 (rIC50 ) concentration against the PPTP cell lines was 25.8 nM. The median rIC50 for the Ewing cell lines was lower than for the remaining cell lines (6.4 vs. 31.1 nM, respectively). In vivo BMN 673 induced statistically significant differences in EFS distribution in 17/43 (39.5%) xenograft models. Three objective regressions were observed: a complete response (CR) in a medulloblastoma line (BT-45), a maintained CR in a Wilms tumor line (KT-10), and a maintained CR in an ependymoma line (BT-41). BMN 673 maintained its high level of activity against KT-10 with a threefold reduction in dose. KT-10 possesses a truncating mutation in PALB2 analogous to PALB2 mutations associated with hereditary breast and ovarian cancer that abrogate homologous recombination (HR) repair. CONCLUSIONS: The PPTP results suggest that single agent BMN 673 may have limited clinical activity against pediatric cancers. Single agent activity is more likely for patients whose tumors have defects in HR repair.


Assuntos
Inibidores Enzimáticos/farmacologia , Mutação/genética , Proteínas Nucleares/genética , Ftalazinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases , Proteínas Supressoras de Tumor/genética , Animais , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Avaliação Pré-Clínica de Medicamentos , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/patologia , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia
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