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1.
Small ; 20(24): e2307963, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38183362

RESUMEN

pH-dependent peptide biomaterials hold tremendous potential for cell delivery and tissue engineering. However, identification of responsive self-assembling sequences with specified secondary structure remains a challenge. In this work, An experimental procedure based on the one-bead one-compound (OBOC) combinatorial library is developed to rapidly screen self-assembling ß-sheet peptides at neutral aqueous solution (pH 7.5) and disassemble at weak acidic condition (pH 6.5). Using the hydrophobic fluorescent molecule thioflavin T (ThT) as a probe, resin beads displaying self-assembling peptides show fluorescence under pH 7.5 due to the insertion of ThT into the hydrophobic domain, and are further cultured in pH 6.5 solution. The beads with extinguished fluorescence are selected. Three heptapeptides are identified that can self-assemble into nanofibers or nanoparticles at pH 7.5 and disassemble at pH 6.5. P1 (LVEFRHY) shows a rapid acid response and morphology transformation with pH modulation. Changes in the charges of histidine and hydrophobic phenyl motif of phenylalanine may play important roles in the formation of pH-responsive ß-sheet nanofiber. This high-throughput screening method provides an efficient way to identify pH-dependent ß-sheet self-assembling peptide and gain insights into structural design of such nanomaterials.


Asunto(s)
Péptidos , Concentración de Iones de Hidrógeno , Péptidos/química , Conformación Proteica en Lámina beta , Ensayos Analíticos de Alto Rendimiento/métodos , Nanofibras/química , Interacciones Hidrofóbicas e Hidrofílicas , Benzotiazoles/química
2.
Am J Primatol ; 85(6): e23493, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37056028

RESUMEN

Predicting the spatial distribution of species and suitable areas under global climate change could provide a reference for species conservation and long-term management strategies. Macaca thibetana and Macaca arctoides are two endangered species of Chinese macaques. However, limited information is available on their distribution, and their habitat needs lack proper assessment due to complicated taxonomy and less research attention. In recent years, scholars widely used the maximum entropy (MaxEnt) model to predict the impact of global climate and certain environmental factors on species distribution. Therefore, we used the MaxEnt model to predict the spatiotemporal distribution of both macaque species under six climate change scenarios using occurrence and high-resolution ecological data. We identified climatic factors, elevation, and land cover that shape their distribution range and determined shifts in their habitat range. The results demonstrated that temperature range, annual precipitation, forest land cover, and temperature seasonality, including the precipitation of the driest month are the main factors affecting their distribution. Currently, M. thibetana is mainly concentrated in central, eastern, southern, and southwestern China, and M. arctoides is mainly concentrated in three provinces (Yunnan, Guangxi, and Guangdong) in southern China. The MaxEnt model predicted that the suitable habitat for both species will increase with increased greenhouse emission scenarios. We also found that with the further increase in greenhouse emissions M. thibetana is expected to migrate to western China, and M. arctoides is expected to migrate to western or eastern China. This reinterpretation of the distribution of M. thibetana and M. arctoides in China, and predicted potential suitable habitat and possible migration direction, may provide new insights into the future conservation and management of these two species.


Asunto(s)
Cambio Climático , Macaca arctoides , Macaca , Animales , China , Ecosistema , Distribución Animal
3.
Nano Lett ; 22(20): 8076-8085, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36135098

RESUMEN

Nanomaterials (NMs) inevitably adsorb proteins in blood and form "protein corona" upon intravenous administration as drug carriers, potentially changing the biological properties and intended functions. Inspired by anti-adhesion properties of natural proteins, herein, we employed the one-bead one-compound (OBOC) combinatorial peptide library method to screen anti-adhesion peptides (AAPs) against proteins. The library beads displaying random peptides were screened with three fluorescent-labeled plasma proteins. The nonfluorescence beads, presumed to have anti-adhesion property against the proteins, were isolated for sequence determination. These identified AAPs were coated on gold nanorods (GNRs), enabling significant extension of the blood circulating half-life of these GNRs in mice to 37.8 h, much longer than that (26.6 h) of PEG-coated GNRs. In addition, such AAP coating was found to alter the biodistribution profile of GNRs in mice. The bioinspired screening strategy and resulting peptides show great potential for enhancing the delivery efficiency and targeting ability of NMs.


Asunto(s)
Nanoestructuras , Biblioteca de Péptidos , Ratones , Animales , Técnicas Químicas Combinatorias/métodos , Distribución Tisular , Péptidos/farmacología , Péptidos/química , Proteínas Sanguíneas , Administración Intravenosa , Oro , Portadores de Fármacos
4.
World J Surg Oncol ; 20(1): 192, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35689233

RESUMEN

BACKGROUND: Microwave ablation (MWA) is a potentially curative treatment for unresectable patients with hepatocellular carcinoma (HCC) ≤ 3 cm, while its therapeutic efficacy decreases significantly for HCC > 3cm. Previous studies have demonstrated that conventional transarterial chemoembolization (cTACE) combined with MWA (cTACE-MWA) may improve local tumor control rate and reduce the recurrence rate for HCC > 3cm. However, there have been few study designs to analyze the clinical efficacy of cTACE-MWA for medium-sized HCC (3-5cm). Therefore, this study aims to compare the clinical efficacy and safety of cTACE-MWA with cTACE alone for a single medium-sized HCC of 3-5 cm in diameter. METHODS: We retrospectively investigate the data of 90 patients with a single medium-sized HCC who were referred to our hospital and underwent cTACE-MWA or cTACE alone from December 2017 to March 2020. Then, patients were identified with propensity score-matched (1:1). The local tumor response to treatment and time to progression (TTP) were compared using mRECIST criteria between the cTACE-MWA group and the cTACE group. RESULTS: A total of 42 patients were included after matching (cTACE-MWA: 21; cTACE: 21). Comparing with cTACE, cTACE-MWA demonstrate significantly better local tumor control (ORR: 95.2% vs 61.9%, p = 0.02; DCR: 95.2% vs 66.7%, p = 0.045) and TTP (median 19.8 months vs 6.8 months, p < 0.001). The 1- and 2-year cumulative probabilities of OS were 100% and 95% in the cTACE-MWA group, which were significantly higher than those in the cTACE group (95% and 76%) (p = 0.032). Multivariate Cox regression analysis illustrates that cTACE-MWA was associated with better TTP (hazard ratio, 0.28; 95% CI: 0.1, 0.76; p = 0.012), but tumor size was associated with worse TTP (hazard ratio, 1.71; 95% CI: 1.01, 2.89; p = 0.045). CONCLUSIONS: cTACE followed by MWA improved TTP and OS in patients with a single medium-sized HCC, and no major complication was observed in this study.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirugía , Microondas/uso terapéutico , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento
5.
Biomacromolecules ; 20(2): 882-892, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30621390

RESUMEN

Despite recent advances in tumor treatment through cancer immunotherapy, the efficacy of this approach remains to be improved. Looking forward to high rates of objective clinical response, cancer immunotherapy combined with chemotherapy has gained increasing attention recently. Here, we constructed liposomes with matrix metalloproteinases (MMPs) responsive moiety and PD-L1 inhibitor conjugate combine with low dose chemotherapy to achieve enhanced antitumor efficacy. Upon introduction of the pH-responsive polymer to LPDp, the coassembly could be almost stable in physiological conditions and tumor microenvironments and release the loaded cargos at the lysosome. MMP-2 enzyme extracellularly secreted by the B16F10 cells could cleave the cross-linker and liberate the PD-L1 inhibitor effectively disrupting the PD-1/PD-L1 interaction in vitro. Low dose DOX encapsulated in the LPDp was capable of sensitizing B16F10 cells to CTLs by inducing overexpression of M6PR on tumor cell membranes. In comparison with free PD-L1 inhibitor, LPDp improved the biodistribution and on-demand release of the peptide inhibitor in tumor regions following administration. LPDp achieved the optimal tumor suppression efficiency (∼78.7%), which demonstrated the significantly enhanced antitumor effect ( P < 0.01) than that of LPp (∼57.5%) as well as that of LD (<40%), attributing to synergistic contribution from the substantial increase in M6PR expression on tumor cells and the blockade of immune checkpoints. This strategy provides a strong rationale for combining standard-of-care chemotherapy with relative nontoxic and high specific immunotherapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Antígeno B7-H1/antagonistas & inhibidores , Liposomas/química , Metaloproteinasas de la Matriz/metabolismo , Polímeros de Estímulo Receptivo/química , Microambiente Tumoral , Animales , Línea Celular Tumoral , Doxorrubicina/administración & dosificación , Liberación de Fármacos , Quimioterapia/métodos , Concentración de Iones de Hidrógeno , Inmunoterapia/métodos , Ratones
6.
Small ; 12(39): 5423-5430, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27511451

RESUMEN

Au-BP7@SP nanohybrids with active motion under NIR laser irradiation can effectively enhance the temperature of tumor potentially by converting the kinetic energy to thermal energy, enhancing the killing efficiency of the tumor cells compared with Au@SP. The study provides an insight of nanohybrids' effect on photothermal treatment and opens a new avenue to cancer treatment by using self-propulsion Janus nanohybrids.


Asunto(s)
Hipertermia Inducida , Rayos Infrarrojos , Neoplasias/terapia , Fototerapia , Animales , Supervivencia Celular , Humanos , Células MCF-7 , Ratones , Nanopartículas/química , Nanopartículas/ultraestructura , Neoplasias/patología , Temperatura
7.
World J Gastrointest Oncol ; 16(7): 2941-2951, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39072162

RESUMEN

BACKGROUND: Subphrenic carcinoma has been identified as a significant risk factor for the thermal ablation of intrahepatic tumors, resulting in a high rate of residual tumor recurrence. Some studies have proposed that combination treatment with transarterial chemoembolization (TACE) followed by radiofrequency ablation is both feasible and safe for tumors in the subphrenic region. However, research specifically examining the therapeutic outcomes of combination therapy using TACE and microwave ablation (TACE-MWA) in subphrenic tumors is lacking. AIM: To evaluate the efficacy and safety of TACE-MWA in patients with subphrenic hepatocellular carcinoma (HCC). METHODS: Between December 2017 and December 2021, 49 patients diagnosed with HCC ≤ 6 cm, who received TACE-MWA, were included in this retrospective cohort study. These patients were classified into subphrenic and non-subphrenic groups based on the distance between the diaphragm and the tumor margin. The rates of local tumor progression (LTP), progression-free survival (PFS), and overall survival (OS) were compared between the two groups. Complications were evaluated by using a grading system developed by the Society of Interventional Radiology. RESULTS: After a median follow-up time of 38 mo, there were no significant differences in LTP between the subphrenic and non-subphrenic groups (27.3% and 22.2% at 5 years, respectively; P = 0.66), PFS (55.5% at 5 years in both groups; P = 0.91), and OS (85.0% and 90.9% in the subphrenic and non-subphrenic groups at 5 years; P = 0.57). However, a significantly higher rate of LTP was observed in subphrenic HCC > 3 cm compared to those ≤ 3 cm (P = 0.085). The dosage of iodized oil [hazard ratio (HR): 1.52; 95% confidence interval (CI): 1.11-2.08; P = 0.009] and multiple tumors (HR: 13.22; 95%CI: 1.62-107.51; P = 0.016) were independent prognostic factors for LTP. There were no significant differences in complication rates between the two groups (P = 0.549). CONCLUSION: Combined TACE and MWA was practical and safe for managing subphrenic HCC. The efficacy and safety levels did not vary significantly when tumors outside the subphrenic region were treated.

8.
Adv Mater ; : e2407826, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39313982

RESUMEN

The extended use of androgen deprivation therapy (ADT) may often lead to the progression from castration-sensitive prostate cancer (CSPC) to castration-resistant prostate cancer (CRPC) in prostate cancer. To address this, it is essential to inhibit the nuclear translocation of the androgen receptor (AR) as part of an effective disease-modifying strategy. Microtubules play a central role in facilitating AR nuclear translocation, highlighting their importance as a therapeutic target. In this regard, a designated as the targeted microtubules transformable nanopeptide system (MTN) is developed. This system is designed to disrupt microtubule structure and function through dual-targeting of prostate-specific membrane antigen (PSMA) and ß-tubulin. Initially, MTN targets prostate cells via PSMA and then specifically binds to ß-tubulin within microtubules, leading to the formation of nanofibers. These nanofibers subsequently induce the polymerization of microtubules, thereby disrupting AR transport. Notably, MTN exhibits efficient and prolonged suppression of prostate cancer across the spectrum from CSPC to CRPC, with a highly favorable safety profile in normal cells. These findings highlight the potential of MTN as a novel and promising approach for comprehensive prostate cancer therapy throughout its entire progression.

9.
Trends Ecol Evol ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39242333

RESUMEN

Group-living animals sleep together, yet most research treats sleep as an individual process. Here, we argue that social interactions during the sleep period contribute in important, but largely overlooked, ways to animal groups' social dynamics, while patterns of social interaction and the structure of social connections within animal groups play important, but poorly understood, roles in shaping sleep behavior. Leveraging field-appropriate methods, such as direct and video-based observation, and increasingly common on-animal motion sensors (e.g., accelerometers), behavioral indicators can be tracked to measure sleep in multiple individuals in a group of animals simultaneously. Sleep proximity networks and sleep timing networks can then be used to investigate the collective dynamics of sleep in wild group-living animals.

10.
Zhongguo Zhong Yao Za Zhi ; 38(22): 3888-92, 2013 Nov.
Artículo en Zh | MEDLINE | ID: mdl-24558870

RESUMEN

To compare and study the decoction and dissolution of active constituents in crude and processed Corni Fructus. HPLC, the traditional Chinese medicine (TCM) decoction method and the dissolution methods were adopted to compare and study the decoction yield and dissolution rate of loganin and morroniside, active constituents in crude and processed Corni Fructus. The results showed that the content of active constituents loganin and morroniside in crude and processed Corni Fructus did not change significantly; compared with crude Corni Fructus, processed Corni Fructus (decoction) contained much higher loganin, with no obvious change in morroniside; compared with crude Corni Fructus, processed Corni Fructus (extracts) showed no significant difference in loganin dissolution, but notable increase in morroniside dissolution in intestinal fluid; in gastric fluid, processed Corni Fructus showed significant increase in loganin and morroniside dissolutions. However, in comprehensive consideration of the decoction dose in clinical administration, and calculated on the basis of the formula of the decoction yield x dissolution rate = decoction-dissolution product, it showed increase in the decoction-dissolution products of both of the active constituents loganin and morroniside, with significant difference. This suggested that processed Corni Fructus is superior to crude Corni Fructus in clinical application. In this article, we proposed to compare the changes in decoction and dissolution of active constituents in crude and processed Corni Fructus, study the decoction-dissolution product, and then apply it in the quality evaluation of crude and processed Corni Fructus.


Asunto(s)
Cornus/química , Composición de Medicamentos/métodos , Medicamentos Herbarios Chinos/química , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacocinética , Humanos , Mucosa Intestinal/metabolismo , Modelos Biológicos , Solubilidad
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