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1.
Exp Cell Res ; 435(2): 113933, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38296018

RESUMO

Natural killer (NK) cells are triggered by the innate immune response in the tumor microenvironment. The extensive set of stimulating and inhibiting receptors mediates the target recognition of NK cells, and controls the strength of the effector reaction countering specific targeted cells. Yet, lacking major MHC (histocompatibility complex) MICA/B class I chain-related proteins on the membrane of tumor cells results in the failure of NK cell recognition and ability to resist NK cell destruction. Searching databases and molecular docking suggested that in cervical cancer, pterostilbene (3,5-dimethoxy-40-hydroxystilbene; PTS) in Vaccinium corymbosum extract could constrain PI3K/AKT signaling and improving the MICA/B expression. In flow cytometry, MTT assay, viability/cytotoxicity assay, and colony development assays, PTS reduced the development of cervical cancer cells and increased apoptosis. The quantitative real-time PCR (qRT-PCR) and a Western blot indicate that PTS controlled the cytolytic action of NK cells in tumor cells via increasing the MICA/B expression, thus modifying the anti-tumor immune response in cervical cancer.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias do Colo do Útero , Feminino , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Classe I/genética , Células Matadoras Naturais , Transdução de Sinais , Citotoxicidade Imunológica , Microambiente Tumoral
2.
Anal Chem ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39445477

RESUMO

The differentiation and maturation of osteoblasts are essential for bone formation. Zn2+ plays a crucial role in cell differentiation and is involved in osteogenic differentiation. The concentration and distribution of Zn2+ in the nucleus and cytoplasm indicate the differentiation states of osteoblasts. However, there is an absence of a real-time method for monitoring the dynamic fluctuations of endogenous Zn2+ within the nucleus. Here, a novel Zn2+ fluorescent probe (NTAD-N1) with nuclear membrane permeability was designed and developed, allowing for distribution throughout the entire cell, including the nucleus. The NTAD-N1 probe successfully showed the dynamic distribution and concentration changes of Zn2+ in the nucleus and cytoplasm of preosteoblast MC3T3-E1 during the 21-day differentiation period. The results showed that free Zn2+ increased significantly during differentiation of osteoblasts (2-21 days). Importantly, after 4 days of differentiation, osteoblasts are mainly distributed in the nucleus, which is confirmed by metallothionein expression. Subsequently, the level of free Zn2+ in the cytoplasm remained at a high level, which promoted the increase in alkaline phosphatase activity and inhibited the activity of cis-aconitase in the tricarboxylic acid cycle, resulting in the accumulation of citric acid. This series of events promotes the formation of mineralized nodules. In the process of osteoblast differentiation, the detection time of Zn2+ (≤7 days) is ahead of the late marker of alkaline phosphatase (14 days) and mineralized nodules (14-21 days). This indicates that Zn2+ can be used as a biomarker and an intervention point for early differentiation of osteoblasts.

3.
Mol Pharm ; 20(9): 4574-4586, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37307591

RESUMO

SLC16A1 and SLC16A3 (SLC16A1/3) are highly expressed in cervical cancers and associated with the malignant biological behavior of cancer. SLC16A1/3 is the critical hub for regulating the internal and external environment, glycolysis, and redox homeostasis in cervical cancer cells. Inhibiting SLC16A1/3 provides a new thought to eliminate cervical cancer effectively. There are few reports on effective treatment strategies to eliminate cervical cancer by simultaneously targeting SLC16A1/3. GEO database analysis and quantitative reverse transcription polymerase chain reaction experiment were used to confirm the high expression of SLC16A1/3. The potential inhibitor of SLC16A1/3 was screened from Siwu Decoction by using network pharmacology and molecular docking technology. The mRNA levels and protein levels of SLC16A1/3 in SiHa and HeLa cells treated by Embelin (EMB) were clarified, respectively. Furthermore, the Gallic acid-iron (GA-Fe) drug delivery system was used to improve its anti-cancer performance. Compared with normal cervical cells, SLC16A1/3 mRNA was over-expressed in SiHa and HeLa cells. Through the analysis of Siwu Decoction, a simultaneously targeted SLC16A1/3 inhibitor EMB was discovered. It was found for the first time that EMB promoted lactic acid accumulation and further induced redox dyshomeostasis and glycolysis disorder by simultaneously inhibiting SLC16A1/3. The gallic acid-iron-Embelin (GA-Fe@EMB) drug delivery system delivered EMB, which had a synergistic anti-cervical cancer effect. Under the irradiation of a near-infrared laser, the GA-Fe@EMB could elevate the temperature of the tumor area effectively. Subsequently, EMB was released and mediated the lactic acid accumulation and the GA-Fe nanoparticle synergistic Fenton reaction to promote ROS accumulation, thereby increasing the lethality of the nanoparticles on cervical cancer cells. GA-Fe@EMB can target cervical cancer marker SLC16A1/3 to regulate glycolysis and redox pathways, synergistically with photothermal therapy, which provides a new avenue for the synergistic treatment of malignant cervical cancer.


Assuntos
Nanopartículas , Neoplasias do Colo do Útero , Feminino , Humanos , Células HeLa , Ferro , Ácido Gálico , Simulação de Acoplamento Molecular , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Oxirredução , Glicólise
4.
J Nanobiotechnology ; 20(1): 365, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933376

RESUMO

The failure of orthopedic and dental implants is mainly caused by biomaterial-associated infections and poor osseointegration. Surface modification of biomedical materials plays a significant role in enhancing osseointegration and anti-bacterial infection. In this work, a non-linear relationship between the micro/nano surface structures and the femtosecond laser processing parameters was successfully established based on an artificial neural network. Then a controllable functional surface with silver nanoparticles (AgNPs) to was produced to improve the cytocompatibility and antibacterial properties of biomedical titanium alloy. The surface topography, wettability, and Ag+ release were carefully investigated. The effects of these characteristics on antibacterial activity and cytocompatibilty were also evaluated. Results show that the prepared surface is hydrophobic, which can prevent the burst release of Ag+ in the initial stage. The prepared surface also shows both good cytocompatibility toward the murine calvarial preosteoblasts MC3T3-E1 cells (derived from Mus musculus (mouse) calvaria) and good antibacterial effects against Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, which is caused by the combined effect of appropriate micro/nano-structured feature and reasonable Ag+ release rate. We do not only clarify the antibacterial mechanism but also demonstrate the possibility of balancing the antibacterial and osteointegration-promoting properties by micro/nano-structures. The reported method offers an effective strategy for the patterned surface modification of implants.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Escherichia coli , Lasers , Nanopartículas Metálicas/química , Camundongos , Redes Neurais de Computação , Prata/química , Prata/farmacologia , Staphylococcus aureus , Propriedades de Superfície , Titânio/química
5.
Opt Express ; 28(17): 25528-25544, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32907071

RESUMO

Bone drilling has been widely used in medical surgeries such as repair and fixation in orthopedics. Traditional drilling method using drill-bits inevitably causes significant thermal and mechanical trauma in the adjacent bone tissues. This paper demonstrates the feasibility of femtosecond laser drilling in vitro large-size holes on the sheepshank bone with high efficiency and minimal collateral damage. A Yb:KGW femtosecond laser was utilized to drill millimeter-scale holes on the bone under different cooling conditions including gas- and water-assisted processes. Scanning electron microscopy, confocal laser scanning microscopy and infrared thermographic imaging system were used to investigate the residual debris, removal rate, bone temperature variation and hole morphology. Histological examination, Fourier transform infrared spectroscopy and Raman spectroscopy were employed to study thermal damage. Results show that a 4 mm hole with smooth and clean surface was successfully drilled on the bone, and the highest removal rate of 0.99 mm3/s was achieved, which was twenty times higher than the previous study of 0.05 mm3/s. Moreover, bone and bone marrow were distinguished by real-time monitoring system during laser drilling. This work demonstrates the potential for clinical applications using an ultrafast laser to produce crack-free large-size bone holes.


Assuntos
Lasers de Estado Sólido , Procedimentos Ortopédicos/instrumentação , Tíbia/cirurgia , Animais , Fenômenos Biomecânicos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Ovinos , Termografia
6.
Heliyon ; 10(2): e24052, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293361

RESUMO

Aims: Atrial fibrillation/atrial flutter (AF/AFL) is a critical public health issue worldwide, and its epidemiological patterns have changed over the decades. This work aimed to assess the global trends of AF/AFL and attributable risks from 1990 to 2019. Methods and results: The present study utilized data from the Global Burden of Disease Study 2019 to examine the temporal trends, attributable risks, and projections of AF/AFL. The estimated annual percentage change (EAPC) and age-standardized rate (ASR) were employed for this purpose. The findings revealed that in 2019, AF/AFL accounted for 4.72 million incident cases, 59.70 million prevalent cases, 0.32 million deaths, and 8.39 million disability-adjusted life years (DALYs). Furthermore, the results indicated that males under 70 years of age had a higher incidence, prevalence, and DALYs than females, while the rates were similar for both genders between 70 and 74 years. However, this pattern was reversed in individuals over the age of 75, with females exhibiting a higher total incidence, prevalence, and DALYs than males. The age-standardized rates (ASRs) of prevalence, incidence, mortality, and DALYs increased with an increase in the socio-demographic index (SDI). The three primary contributors to AF/AFL were high systolic blood pressure, high body-mass index, and smoking. Majority of risk factors exhibited a unimodal distribution, with a peak between the ages of 50 and 70. Conclusions: The disease burden of AF/AFL is still severe worldwide and getting worse. To encourage prevention and treatment, systematic regional surveillance of AF/AFL should be put in place.

7.
RSC Adv ; 14(9): 6199-6204, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38375019

RESUMO

In this work, hierarchically porous PLA (polylactic acid) shape memory nonwovens were prepared by electrospinning its blend solution with PEO (polyethylene oxide) and subsequent water etching. Based on shape memory effect resulting from tiny crystals and the amorphous matrix of PLA, the switch between compact and porous surfaces has been achieved via cyclical hot-pressing and recovery in a hot water bath. After hot-pressing, the disappearance of hierarchical pores contributes to compact surface, enabling embedding of the target molecule in PLA nonwoven (i.e., CLOSE state). Upon exposure to heat, PLA nonwoven recovers to its permanent shape and exhibits a porous surface, providing a penetrative diffusion pathway for small molecules (i.e., OPEN state). The hierarchically porous structure and shape memory effect endow PLA nonwoven with the capability of rapid release. Our results provide a good candidate for some potential applications, such as temperature-controlled quick-release of catalysts and drugs.

8.
Nanoscale ; 16(27): 13061-13070, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38887082

RESUMO

The rise of two-dimensional (2D) materials has provided a confined geometry and yielded methods for guiding electrons at the nanoscale level. 2D material-enabled electronic devices can interact and transduce the subtle charge perturbation and permit significant advancement in molecule discrimination technology with high accuracy, sensitivity, and specificity, leaving a significant impact on disease diagnosis and health monitoring. However, high-performance biosensors with scalable fabrication ability and simple protocols have yet to be fully realized due to the challenges in wafer-scale 2D film synthesis and integration with electronics. Here, we propose a molybdenum oxide (MoOx)-interdigitated electrode (IDE)-based label-free biosensing chip, which stands out for its wafer-scale dimension, tunability, ease of integration and compatibility with the complementary metal-oxide-semiconductor (CMOS) fabrication. The device surface is biofunctionalized with monoclonal anti-carcinoembryonic antigen antibodies (anti-CEA) via the linkage agent (3-aminopropyl)triethoxysilane (APTES) for carcinoembryonic antigen (CEA) detection and is characterized step-by-step to reveal the working mechanism. A wide range and real-time response of the CEA concentration from 0.1 to 100 ng mL-1 and a low limit of detection (LOD) of 0.015 ng mL-1 were achieved, meeting the clinical requirements for cancer diagnosis and prognosis in serum. The MoOx-IDE biosensor also demonstrates strong surface affinity towards molecules and high selectivity using L-cysteine (L-Cys), glycine (Gly), glucose (Glu), bovine serum albumin (BSA), and immunoglobulin G (IgG). This study showcases a simple, scalable, and low-cost strategy to create a nanoelectronic biosensing platform to achieve high-performance cancer biomarker discrimination capabilities.


Assuntos
Técnicas Biossensoriais , Antígeno Carcinoembrionário , Molibdênio , Óxidos , Molibdênio/química , Óxidos/química , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/análise , Humanos , Eletrodos , Limite de Detecção , Técnicas Eletroquímicas , Semicondutores
9.
BJU Int ; 108(2 Pt 2): E84-90, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21050361

RESUMO

OBJECTIVE: To investigate whether mammalian target of rapamycin (mTOR) inhibition by rapamycin is therapeutically efficacious in combination with cisplatin for bladder cancer. MATERIALS AND METHODS: Using a panel of human urothelial carcinoma cell lines, we determined the effect of rapamycin on cell viability, cell-cycle progression, signalling and apoptosis. The effect of mTOR inhibition on chemosensitivity was investigated by treating cells with rapamycin, alone, or with cisplatin. The effect of rapamycin or cisplatin treatment was assessed in xenograft mice inoculated with urothelial carcinoma cells. Expression of p-mTOR in human bladder cancer specimens was assessed using a tissue microarray. RESULTS: Treatment with rapamycin significantly decreased cell viability in UMUC3 (P = 0.004) and 253J (P < 0.001) cells. It induced arrest in the G(0) -G(1) phase and decreased activation of p-mTOR and its downstream effector, p-S6K, in both cell lines. Treatment with rapamycin increased the ability of cisplatin to inhibit cell viability in UMUC3 (P = 0.002) and 253J (P = 0.03) cells. No evidence for apoptosis induction was noted after treatment with rapamycin alone. Mouse xenografts of UMUC3 cells revealed that rapamycin significantly prolonged survival and enhanced the therapeutic efficacy of cisplatin. In patient urothelial carcinoma specimens, p-mTOR expression was increased in cancer vs non-tumour bladder tissue in 65/203 (32.0%) tumours. CONCLUSIONS: mTOR blockade inhibits urothelial carcinoma cell proliferation and enhances the effectiveness of cisplatin. Suppression of the mTOR pathway has the potential to be a therapeutic target in bladder cancer for selected patients.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células de Transição/patologia , Cisplatino/farmacologia , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células de Transição/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/metabolismo , Urotélio/patologia
10.
Food Chem ; 343: 128498, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33229156

RESUMO

The acquisition of resveratrol from Polygonum cuspidatum is complicated and costs organic solvents due to extraction and hydrolysis of its corresponding glycoside (polydatin). In this work, a novel one-pot method based on deep eutectic solvent (DES) was developed for simultaneous extraction and conversion of polydatin to resveratrol from Polygonum cuspidatum for the first time. The extraction yield of resveratrol by DES-based one-pot method were significantly higher than that of water, methanol and ethanol. After optimization by One-Variable-at-a-Time and response surface methodology, the extraction yield of resveratrol reached 12.26 ± 0.14 mg/g within 80 min. The conversation efficiency of polydatin to resveratrol in Polygonum cuspidatum from five different origins was more than 96.3%. Scanning electron microscope results indicated the selected DES disrupted plant cell walls to enhance the yield of resveratrol. The results indicated that one green method was successfully established for efficient extraction and conversion of polydatin to resveratrol from Polygonum cuspidatum.


Assuntos
Fracionamento Químico/métodos , Fallopia japonica/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Resveratrol/química , Solventes/química , Estilbenos/química , Estilbenos/isolamento & purificação , Hidrólise
11.
Nanomaterials (Basel) ; 9(7)2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31247961

RESUMO

The integration of surface-enhanced Raman scattering (SERS) and surface-enhanced fluorescence (SEF) has attracted increasing interest and is highly probable to improve the sensitivity and reproducibility of spectroscopic investigations in biomedical fields. In this work, dual-mode SERS and SEF hierarchical structures have been developed on a single bio-metallic substrate. The hierarchical structure was composed of micro-grooves, nano-particles, and nano-ripples. The crystal violet was selected as reporter molecule and both the intensity of Raman and fluorescence signals were enhanced because of the dual-mode SERS-SEF phenomena with enhancement factors (EFs) of 7.85 × 105 and 14.32, respectively. The Raman and fluorescence signals also exhibited good uniformity with the relative standard deviation value of 2.46% and 5.15%, respectively. Moreover, the substrate exhibited high sensitivity with the limits of detection (LOD) as low as 1 × 10-11 mol/L using Raman spectroscopy and 1 × 10-10 mol/L by fluorescence spectroscopy. The combined effect of surface plasmon resonance and "hot spots" induced by the hierarchical laser induced periodical surface structures (LIPSS) was mainly contributed to the enhancement of Raman and fluorescence signal. We propose that the integration of SERS and SEF in a single bio-metallic substrate is promising to improve the sensitivity and reproducibility of detection in biomedical investigations.

12.
J Mol Biol ; 357(3): 1009-25, 2006 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-16473367

RESUMO

Although the denaturant-induced unfolding transition of cytochrome c was initially thought to be a cooperative process, recent spectroscopic studies have shown deviations from two-state behavior consistent with accumulation of an equilibrium intermediate. However, little is known about the structural and thermodynamic properties of this state, and whether it is stabilized by the presence of non-native heme ligands. We monitored the reversible denaturant-induced unfolding equilibrium of oxidized horse cytochrome c using various spectroscopic probes, including fluorescence, near and far-UV CD, heme absorbance bands in the Soret, visible and near-IR regions of the spectrum, as well as 2D NMR. Global fitting techniques were used for a quantitative interpretation of the results in terms of a three-state model, which enabled us to determine the intrinsic spectroscopic properties of the intermediate. A well-populated intermediate was observed in equilibrium experiments at pH 5 using either guanidine-HCl or urea as a denaturant, both for wild-type cytochrome c as well as an H33N mutant chosen to prevent formation of non-native His-heme ligation. For a more detailed structural characterization of the intermediate, we used 2D 1H-15N correlation spectroscopy to follow the changes in peak intensity for individual backbone amide groups. The equilibrium state observed in our optical and NMR studies contains many native-like structural features, including a well-structured alpha-helical sub-domain, a short Trp59-heme distance and solvent-shielded heme environment, but lacks the native Met80 sulfur-iron linkage and shows major perturbations in side-chain packing and other tertiary interactions. These structural properties are reminiscent of the A-state of cytochrome c, a compact denatured form found under acidic high-salt conditions, as well as a kinetic intermediate populated at a late stage of folding. The denaturant-induced intermediate also resembles alkaline forms of cytochrome c with altered heme ligation, suggesting that disruption of the native methionine ligand favors accumulation of structurally analogous states both in the presence and absence of non-native ligands.


Assuntos
Citocromos c/química , Citocromos c/metabolismo , Dobramento de Proteína , Substituição de Aminoácidos , Animais , Citocromos c/genética , Guanidina , Cavalos , Desnaturação Proteica , Espectrofotometria , Ureia
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