Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Plant J ; 117(2): 483-497, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37901950

RESUMEN

Plants grown under low magnesium (Mg) soils are highly susceptible to encountering light intensities that exceed the capacity of photosynthesis (A), leading to a depression of photosynthetic efficiency and eventually to photooxidation (i.e., leaf chlorosis). Yet, it remains unclear which processes play a key role in limiting the photosynthetic energy utilization of Mg-deficient leaves, and whether the plasticity of A in acclimation to irradiance could have cross-talk with Mg, hence accelerating or mitigating the photodamage. We investigated the light acclimation responses of rapeseed (Brassica napus) grown under low- and adequate-Mg conditions. Magnesium deficiency considerably decreased rapeseed growth and leaf A, to a greater extent under high than under low light, which is associated with higher level of superoxide anion radical and more severe leaf chlorosis. This difference was mainly attributable to a greater depression in dark reaction under high light, with a higher Rubisco fallover and a more limited mesophyll conductance to CO2 (gm ). Plants grown under high irradiance enhanced the content and activity of Rubisco and gm to optimally utilize more light energy absorbed. However, Mg deficiency could not fulfill the need to activate the higher level of Rubisco and Rubisco activase in leaves of high-light-grown plants, leading to lower Rubisco activation and carboxylation rate. Additionally, Mg-deficient leaves under high light invested more carbon per leaf area to construct a compact leaf structure with smaller intercellular airspaces, lower surface area of chloroplast exposed to intercellular airspaces, and CO2 diffusion conductance through cytosol. These caused a more severe decrease in within-leaf CO2 diffusion rate and substrate availability. Taken together, plant plasticity helps to improve photosynthetic energy utilization under high light but aggravates the photooxidative damage once the Mg nutrition becomes insufficient.


Asunto(s)
Anemia Hipocrómica , Brassica napus , Brassica napus/metabolismo , Ribulosa-Bifosfato Carboxilasa/metabolismo , Magnesio , Dióxido de Carbono , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo
2.
BMC Cancer ; 24(1): 181, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321381

RESUMEN

OBJECTIVES: In this meta-analysis, we conducted a comparative analysis of the safety and efficacy of hypofractionated and conventional fractionated radiotherapy in individuals who had undergone surgery for breast cancer. METHODS: This study involved a systematic and independent review of relevant research articles published in reputable databases such as PubMed, Embase, Cochrane Library, and Web of Science. Two investigators conducted the review, which included studies published up to January 3, 2023. The quality of the eligible studies was evaluated and data were extracted using Review Manager software 5.4 (RevMan 5.4) to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The analysis comprised 35 studies and encompassed a collective sample of 18,246 individuals diagnosed with breast cancer. We did not find a statistically significant disparity in efficacy between conventional fractionated (CF) radiotherapy and hypofractionated (HF) radiotherapy regarding local recurrence (LR; OR = 0.91, 95% CI: 0.76-1.09, P = 0.30), disease-free survival (DFS; OR = 1.20, 95% CI: 1.01-1.42, P = 0.03), and overall survival (OS; OR = 1.08, 95% CI: 0.93-1.26, P = 0.28). Concerning safety, there was no significant difference between the HF and CF regimens in terms of breast pain, breast atrophy, lymphedema, pneumonia, pulmonary fibrosis, telangiectasia, and cardiotoxicity. However, the HF regimen resulted in lower skin toxicity (OR = 0.43, 95% CI: 0.33-0.55, P < 0.01) and improved patient fatigue outcomes (OR = 0.73, 95% CI: 0.60 - 0.88, P < 0.01). CONCLUSIONS: Although there is no substantial difference in LR, DFS, OS, or many other side effects between the HF and CF regimens, the HF regimen reduces skin toxicity and relieves patient fatigue. If these two issues need to be addressed in clinical situations, the HF regimen may be a superior alternative to conventional radiotherapy in postoperative breast cancer patients.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Mama/patología , Neoplasias de la Mama/radioterapia , Supervivencia sin Enfermedad , Supervivencia sin Progresión , Hipofraccionamiento de la Dosis de Radiación
3.
J Basic Microbiol ; 64(1): 119-127, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37562983

RESUMEN

The transcription factor (TF)-mediated regulatory network controlling lincomycin production in Streptomyces lincolnensis is yet to be fully elucidated despite several types of associated TFs having been reported. SLCG_2919, a tetracycline repressor (TetR)-type regulator, was the first TF to be characterized outside the lincomycin biosynthetic cluster to directly suppress the lincomycin biosynthesis in S. lincolnensis. In this study, improved genomic systematic evolution of ligands by exponential enrichment (gSELEX), an in vitro technique, was adopted to capture additional SLCG_2919-targeted sequences harboring the promoter regions of SLCG_6675, SLCG_4123-4124, SLCG_6579, and SLCG_0139-0140. The four DNA fragments were confirmed by electrophoretic mobility shift assays (EMSAs). Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) showed that the corresponding target genes SLCG_6675 (anthranilate synthase), SLCG_0139 (LysR family transcriptional regulator), SLCG_0140 (beta-lactamase), SLCG_6579 (cytochrome P450), SLCG_4123 (bifunctional DNA primase/polymerase), and SLCG_4124 (magnesium or magnesium-dependent protein phosphatase) in ΔSLCGL_2919 were differentially increased by 3.3-, 4.2-, 3.2-, 2.5-, 4.6-, and 2.2-fold relative to those in the parental strain S. lincolnensis LCGL. Furthermore, the individual inactivation of these target genes in LCGL reduced the lincomycin yield to varying degrees. This investigation expands on the known DNA targets of SLCG_2919 to control lincomycin production and lays the foundation for improving industrial lincomycin yields via genetic engineering of this regulatory network.


Asunto(s)
Proteínas Bacterianas , Magnesio , Streptomyces , Magnesio/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Antibacterianos , Lincomicina , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tetraciclina , ADN , Regulación Bacteriana de la Expresión Génica
4.
Opt Express ; 31(6): 9904-9914, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-37157550

RESUMEN

We theoretically investigate the combining efficiency and combined beam quality degradation induced by beam array misalignment in a coherent combining system based on diffractive optical elements. Theoretical model is established based on the Fresnel diffraction. We consider pointing aberration, positioning error and beam size deviation in array emitters as typical misalignments, and discuss their influences on beam combining by this model. The statistical analysis results and the accurate fitting curves of the degradation have been given based on the repetitive simulations with normal distributed random misalignments. According to the results, the combining efficiency is affected greatly by the pointing aberration and position error of the laser array, while the combined beam quality is just affected by the pointing aberration generally. Based on calculation with a series of typical parameters, the standard deviations of the laser array's pointing aberration and position error are required to less than 15µrad and 1µm respectively to maintain an excellent combining efficiency. If we only concentrate on the beam quality, the pointing aberration need to be less than 70µrad.

5.
Biotechnol Lett ; 45(10): 1327-1337, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37526868

RESUMEN

PURPOSE: Viruses, such as Ebola virus (EBOV), evolve rapidly and threaten the human health. There is a great demand to exploit efficient gene-editing techniques for the identification of virus to probe virulence mechanism for drug development. METHODS: Based on lambda Red recombination in Escherichia coli (E. coli), counter-selection, and in vitro annealing, a high-efficiency genetic method was utilized here for precisely engineering viruses. EBOV trVLPs assay and dual luciferase reporter assay were used to further test the effect of mutations on virus replication. RESULTS: Considering the significance of matrix protein VP24 in EBOV replication, the types of mutations within vp24, including several single-base substitutions, one double-base substitution, two seamless deletions, and one targeted insertion, were generated on the multi-copy plasmid of E. coli. Further, the length of the homology arms for recombination and in vitro annealing, and the amount of DNA cassettes and linear plasmids were optimized to create a more elaborate and cost-efficient protocol than original approach. The effects of VP24 mutations on the expression of a reporter gene (luciferase) from the EBOV minigenome were determined, and results indicated that mutations of key sites within VP24 have significant impacts on EBOV replication. CONCLUSION: This precise mutagenesis method will facilitate effective and simple editing of viral genes in E. coli.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Virales/genética , Fiebre Hemorrágica Ebola/genética , Ebolavirus/genética , Ebolavirus/metabolismo , Ingeniería Genética , Recombinación Genética
6.
J Nanobiotechnology ; 20(1): 210, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35524268

RESUMEN

A sort of composite hydrogel with good biocompatibility, suppleness, high conductivity, and anti-inflammatory activity based on polyvinyl alcohol (PVA) and molybdenum sulfide/graphene oxide (MoS2/GO) nanomaterial has been developed for spinal cord injury (SCI) restoration. The developed (MoS2/GO/PVA) hydrogel exhibits excellent mechanical properties, outstanding electronic conductivity, and inflammation attenuation activity. It can promote neural stem cells into neurons differentiation as well as inhibit the astrocytes development in vitro. In addition, the composite hydrogel shows a high anti-inflammatory effect. After implantation of the composite hydrogel in mice, it could activate the endogenous regeneration of the spinal cord and inhibit the activation of glial cells in the injured area, thus resulting in the recovery of locomotor function. Overall, our work provides a new sort of hydrogels for SCI reparation, which shows great promise for improving the dilemma in SCI therapy.


Asunto(s)
Alcohol Polivinílico , Traumatismos de la Médula Espinal , Animales , Antiinflamatorios/uso terapéutico , Disulfuros , Grafito , Hidrogeles , Ratones , Molibdeno/uso terapéutico , Nanogeles , Traumatismos de la Médula Espinal/tratamiento farmacológico
7.
J Mol Struct ; 1268: 133709, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-35846732

RESUMEN

The rapidly evolving Coronavirus Disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide with thousands of deaths and infected cases. For the identification of effective treatments against this disease, the main protease (Mpro) of SARS­CoV­2 was found to be an attractive drug target, as it played a central role in viral replication and transcription. Here, we report the results of high-throughput molecular docking with 1,045,468 ligands' structures from 116 kinds of traditional Chinese medicine (TCM). Subsequently, 465 promising candidates were obtained, showing high binding affinities. The dynamic simulation, ADMET (absorption, distribution, metabolism, excretion and toxicity) and drug-likeness properties were further analyzed the screened docking results. Basing on these simulation results, 23 kinds of Chinese herbal extracts were employed to study their inhibitory activity for Mpro of SARS­CoV­2. Plants extracts from Forsythiae Fructus, Radix Puerariae, Radix astragali, Anemarrhenae Rhizoma showed acceptable inhibitory efficiencies, which were over 70%. The best candidate was Anemarrhenae Rhizoma, reaching 78.9%.

8.
Opt Express ; 29(11): 16781-16803, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34154233

RESUMEN

We use a model to investigate both the temporal and spectral characteristics of a signal lightwave which has been spectrally broadened through phase modulation with a maximal-length sequence (MLS), which is a common type of pseudo-random bit sequence. The enhancement of the stimulated Brillouin scattering (SBS) threshold of the modulated lightwave in a fiber system is evaluated by numerically simulating the coupled three-wave SBS interaction equations. We find that SBS can build up on a nanosecond-level time scale in a short fiber, which can reduce the SBS suppressing capability of MLS modulation waveforms with GHz-level clock rate, if the sub-sequence ("run") lengths with the same symbol (zero or one) of the MLS extend over several nanoseconds. To ensure the SBS buildup is perturbed and thus suppressed also during these long sub-sequences, we introduce a low-pass filter to average the signal over several bits so that the modulation waveform changes gradually even during long runs and amplify the RF modulation waveforms to the level required for sufficient spectral broadening and carrier suppression of the optical signal. We find that the SBS suppression depends non-monotonically on the parameters of the filtered and amplified MLS waveform such as pattern length, modulation depth, and the ratio of low-pass filter cutoff frequency to clock rate for maximum SBS mitigation. We optimize the SBS suppression through numerical simulations and discuss it in terms of the temporal and spectral characteristics of the lightwave and modulation waveform using derived analytical expressions and numerical simulations. The simulations indicate that the normalized SBS threshold reaches a maximum for a RMS modulation depth of 0.56π and a ratio of filter cutoff frequency to clock rate of 0.54 and that MLS9 is superior to other investigated patterns.

9.
Opt Express ; 29(4): 5179-5192, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726058

RESUMEN

Filled-aperture geometries can be obtained using a diffractive optical element (DOE) in the coherent beam combining (CBC) architecture. Minimizing the beam deviation is crucial to maintain single-aperture output and reduce the combining-efficiency losses. In this study, we developed a theoretical model for investigating the combining-efficiency losses with beam deviation in a DOE-based CBC architecture. The beam deviations induced by the DOE-mount-tilt error, emitter-incident angular error, and DOE-groove-tilt error are discussed theoretically in detail and verified experimentally. The combining-efficiency losses caused by the three error sources are calculated. Meanwhile, the combining-efficiency losses affected by the beam size and the DOE period are analyzed. For an 11-channel CBC architecture with a DOE period of 50 µm and a beam size of 30 mm, the maximum combining-efficiency losses caused by the three error sources were 3.2%, 1.87%, and 36.41%, respectively, whereas those in case of a DOE period of 20 µm and a beam size of 10 mm were 14.34%, 8.58%, and 25.29%, respectively. We found that the combining-efficiency loss is most sensitive to the DOE-groove-tilt error.

10.
Opt Lett ; 46(23): 5802-5805, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34851894

RESUMEN

We study the instantaneous response of stimulated Brillouin scattering (SBS) in a fiber system phase modulated by a binary sequence waveform. The buildup time constant of SBS kinetics is investigated analytically and experimentally. A series of binary sequences with adjustable dwell time and sequence period is constructed in order to examine both buildup and suppressing processes for SBS in 15 m short fiber. For a fiber system with SBS buildup time constant within several nanoseconds, the Stokes intensity can be effectively suppressed by implementing a binary sequence phase modulation with a dwell time close to or even less than the buildup time constant. Stokes intensity can be suppressed in several sequence periods, which exhibit a damped-oscillation-like trend.

11.
Biol Direct ; 18(1): 35, 2023 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-37391760

RESUMEN

BACKGROUND: Bicuspid aortic valve (BAV) is the most prevalent congenital valvular heart defect, and around 50% of severe isolated calcific aortic valve disease (CAVD) cases are associated with BAV. Although previous studies have demonstrated the cellular heterogeneity of aortic valves, the cellular composition of specific BAV at the single-cell level remains unclear. METHODS: Four BAV specimens from aortic valve stenosis patients were collected to conduct single-cell RNA sequencing (scRNA-seq). In vitro experiments were performed to further validate some phenotypes. RESULTS: The heterogeneity of stromal cells and immune cells were revealed based on comprehensive analysis. We identified twelve subclusters of VICs, four subclusters of ECs, six subclusters of lymphocytes, six subclusters of monocytic cells and one cluster of mast cells. Based on the detailed cell atlas, we constructed a cellular interaction network. Several novel cell types were identified, and we provided evidence for established mechanisms on valvular calcification. Furthermore, when exploring the monocytic lineage, a special population, macrophage derived stromal cells (MDSC), was revealed to be originated from MRC1+ (CD206) macrophages (Macrophage-to-Mesenchymal transition, MMT). FOXC1 and PI3K-AKT pathway were identified as potential regulators of MMT through scRNA analysis and in vitro experiments. CONCLUSIONS: With an unbiased scRNA-seq approach, we identified a full spectrum of cell populations and a cellular interaction network in stenotic BAVs, which may provide insights for further research on CAVD. Notably, the exploration on mechanism of MMT might provide potential therapeutic targets for bicuspid CAVD.


Asunto(s)
Enfermedad de la Válvula Aórtica , Enfermedad de la Válvula Aórtica Bicúspide , Humanos , Fosfatidilinositol 3-Quinasas , Transcriptoma , Macrófagos
12.
Appl Biochem Biotechnol ; 195(12): 7808-7820, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37093529

RESUMEN

Phospholipase D (PLD) with the higher transphosphatidylation activity was screened from Streptomyces sp. LD0501 basing on the protoplast mutagenesis technology. Then, it was successfully bio-imprinted to form a hyperactivated structure and rigidified by the intramolecular cross-linking, which was immobilized on the nonporous nanoscale silica. Characterization techniques were employed to investigate the structure and physicochemical properties of the catalysts, including Fourier transform infrared (FTIR) spectra and scanning electron microscopy (SEM) analysis. Transphosphatidylation activity and selectivity were improved significantly when immobilized PLD was used. The maximum yield for the production of phosphatidylserine (PS) reached 97% and the side reaction, the hydrolysis, was minimized. These results were further confirmed by the nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis. The imprint-induced characteristics of PLD was successfully "remembered" even in the present of much water. In addition, this immobilized hyperactivated PLD showed the excellent operational stabilities and environmental tolerances.


Asunto(s)
Fosfolipasa D , Fosfolipasa D/genética , Fosfolipasa D/química , Catálisis , Agua/química , Espectroscopía de Resonancia Magnética , Fosfatidilserinas/química
13.
Front Neurorobot ; 17: 1178006, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37214786

RESUMEN

In this article, a tensegrity-based knee mechanism is studied for developing a high-efficiency rehabilitation knee exoskeleton. Moreover, the kinematics and dynamics models of the knee mechanism are explored for bringing about further improvement in controller design. In addition, to estimate the performance of the bionic knee joint, based on the limit function of knee patella, the limit position functionality of the bionic knee joint is developed for enhancing the bionic property. Furthermore, to eliminate the noise item and other disturbances that are constantly generated in the rehabilitation process, a noise-tolerant zeroing neural network (NTZNN) algorithm is utilized to establish the controller. This indicates that the controller shows an anti-noise performance; hence, it is quite unique from other bionic knee mechanism controllers. Eventually, the anti-noise performance and the calculation of the precision of the NTZNN controller are verified through several simulation and contrast results.

14.
Front Surg ; 10: 1293004, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38169674

RESUMEN

Background: Portal vein thrombosis (PVT) is a common postoperative complication in patients with pancreatic cancer (PC), significantly affecting their quality of life and long-term prognosis. Our aim is to establish a new nomogram to predict the risk of PVT after PC surgery. Method: We collected data from 416 patients who underwent PC surgery at our hospital between January 2011 and June 2022. This includes 87 patients with PVT and 329 patients without PVT. The patients were randomly divided into a training group and a validation group at a ratio of 7:3. We constructed a nomogram model using the outcomes from both univariate and multivariate logistic regression analyses conducted on the training group. The nomogram's predictive capacity was assessed using calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA). Results: In the study, the prevalence of PVT was 20.9%. Age, albumin, vein reconstruction and preoperative D-dimer were independent related factors. The model achieved a C-index of 0.810 (95% confidence interval: 0.752-0.867), demonstrating excellent discrimination and calibration performance. The area under the ROC curve of the nomogram was 0.829 (95% CI: 0.750-0.909) in the validation group. DCA confirmed that the nomogram model was clinically useful when the incidence of PVT in patients was 5%-60%. Conclusion: We have established a high-performance nomogram for predicting the risk of PVT in patients undergoing PC surgery. This will assist clinical doctors in identifying individuals at high risk of PVT and taking appropriate preventive measures.

15.
Front Bioeng Biotechnol ; 11: 1158348, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37064237

RESUMEN

Docosahexaenoic acid (DHA)-enriched phosphatidylcholine (PC) has received significant scientific attention due to the health benefits in food and pharmaceutical products. In this work, the edible algal oil rich in DHA-triacylglycerol (DHA-TAG) without pretreatment was first used as the DHA donor for the transesterification of phospholipids (PLs) to prepare three kinds of rare PLs, including DHA-PC, DHA-phosphatidylethanolamine (DHA-PE), and DHA-phosphatidylserine (DHA-PS). Here, 153 protein structures of triacylglycerol lipase (EC 3.1.1.3) were virtually screened and evaluated by transesterification. PLA1 was the best candidate due to a higher DHA incorporation. Results showed that the transesterification of PC with DHA-TAG at 45°C and 0.7% water content (without additional water addition) could produce DHA-PC with 39.1% DHA incorporation at 30 min. The different DHA donors, including forms of fatty acid, methyl ester, and triglycerides, were compared. Molecular dynamics (MD) was used to illustrate the catalytic mechanism at the molecular level containing the diffusions of substrates, the structure-activity relationship of PLA1, and the effect of water content.

16.
Front Oncol ; 13: 1122811, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37284203

RESUMEN

Background: To investigate the clinical significance of preoperative inflammatory status in patients with pancreatic head carcinoma (PHC), we performed a single-center study to assess it. Method: We studied a total of 164 patients with PHC undergoing PD surgery (with or without allogeneic venous replacement) from January 2018 to April 2022. Systemic immune-inflammation index (SII) was the most important peripheral immune index in predicting the prognosis according to XGBoost analysis. The optimal cutoff value of SII for OS was calculated according to Youden index based on the receiver operating characteristic (ROC) curve and the cohort was divided into Low SII group and High SII group. Demographic, clinical data, laboratory data, follow-up data variables were obtained and compared between the two groups. Kaplan-Meier curves, univariable and multivariable Cox regression models were used to determine the association between preoperative inflammation index, nutritional index and TNM staging system with OS and DFS respectively. Results: The median follow-up time was 16 months (IQR 23), and 41.4% of recurrences occurred within 1 year. The cutoff value of SII was 563, with a sensitivity of 70.3%, and a specificity of 60.7%. Peripheral immune status was different between the two groups. Patients in High SII group had higher PAR, NLR than those in Low SII group (P <0.01, <0.01, respectively), and lower PNI (P <0.01). Kaplan-Meier analysis showed significantly poorer OS and DFS (P < 0.001, <0.001, respectively) in patients with high SII. By using the multivariable Cox regression model, high SII (HR, 2.056; 95% CI, 1.082-3.905, P=0.028) was significant predictor of OS. Of these 68 high-risk patients who recurrence within one year, patients with widespread metastasis had lower SII and worse prognosis (P <0.01). Conclusion: High SII was significantly associated with poor prognosis in patients with PHC. However, in patients who recurrence within one year, SII was lower in patients at TNM stage III. Thus, care needs to be taken to differentiate those high-risk patients.

17.
Front Chem ; 11: 1167586, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37007061

RESUMEN

Biomimetic nanocomposites are widely used in the biomedical field because they can effectively solve the problems existing in the current cancer treatment by realizing multi-mode collaborative treatment. In this study, we designed and synthesized a multifunctional therapeutic platform (PB/PM/HRP/Apt) with unique working mechanism and good tumor treatment effect. Prussian blue nanoparticles (PBs) with good photothermal conversion efficiency were used as nuclei and coated with platelet membrane (PM). The ability of platelets (PLTs) to specifically target cancer cells and inflammatory sites can effectively enhance PB accumulation at tumor sites. The surface of the synthesized nanocomposites was modified with horseradish peroxidase (HRP) to enhance the deep penetration of the nanocomposites in cancer cells. In addition, PD-L1 aptamer and 4T1 cell aptamer AS1411 were modified on the nanocomposite to achieve immunotherapy and enhance targeting. The particle size, UV absorption spectrum and Zeta potential of the biomimetic nanocomposite were determined by transmission electron microscope (TEM), Ultraviolet-visible (UV-Vis) spectrophotometer and nano-particle size meter, and the successful preparation was proved. In addition, the biomimetic nanocomposites were proved to have good photothermal properties by infrared thermography. The cytotoxicity test showed that it had a good killing ability of cancer cells. Finally, thermal imaging, tumor volume detection, immune factor detection and Haematoxilin-Eosin (HE) staining of mice showed that the biomimetic nanocomposites had good anti-tumor effect and could trigger immune response in vivo. Therefore, this biomimetic nanoplatform as a promising therapeutic strategy provides new inspiration for the current diagnosis and treatment of cancer.

18.
Sci Rep ; 13(1): 13339, 2023 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-37587214

RESUMEN

There is uncertainty regarding the benefits and drawbacks of various radiation protocols for the treatment of left-sided breast cancer. To address this issue, we conducted a Bayesian network analysis. First, we searched several electronic databases for eligible literature. Next, we pooled the data from twelve studies concerning three-dimensional conformal radiation therapy (3D-CRT), intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT), combined with either deep inspiratory breath-holding (DIBH) or free-breathing (FB) modalities. The integrated cardiac and pulmonary dosimetric indexes for all included treatments were compared using Bayesian networks. A direct meta-analysis indicated that for the two methods of 3D-CRT and IMRT, DIBH technology was more effective than FB in reducing the radiation dose to the heart and lungs. Additionally, according to the network results, DIBH was superior to FB in all six treatment options, regardless of whether the plan was 3D-CRT, IMRT, or VMAT. Besides, the combined data indicated that the FB-3D-CRT regimen had the weakest dosimetric advantage of all the treatments. Excluding FB-3D-CRT, each of the other five treatments had its own specific benefits. This is the first Bayesian study of several radiotherapy regimens for breast cancer patients on the left side, and the findings can be used to select appropriate radiotherapy programs for breast cancer patients.


Asunto(s)
Neoplasias de la Mama , Oncología por Radiación , Neoplasias de Mama Unilaterales , Humanos , Femenino , Neoplasias de Mama Unilaterales/radioterapia , Neoplasias de la Mama/radioterapia , Teorema de Bayes , Protocolos Clínicos
19.
Int J Biol Macromol ; 225: 923-937, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36427613

RESUMEN

Microorganisms induced wound infection and the accompanying excessive inflammatory response is the daunting problems in wound treatment. Due to the lack of corresponding biological functions, traditional wound dressings cannot effectively protect the wound and are prone to induce local infection, excessive inflammation, and vascular damage, resulting in prolonged unhealing. Here, a mussel-inspired strategy was adopted to prepare a multifunctional hydrogel created by H2O2/CuSO4-induced rapid polydopamine (PDA) deposition on carboxymethyl chitosan (CMC)/sodium alginate (Alg) based hydrogel, termed as CAC/PDA/Cu(H2O2). The prepared CAC/PDA/Cu(H2O2) hydrogel features excellent biocompatibility, adequate mechanical properties, and good degradability. Moreover, the CAC/PDA/Cu(H2O2) hydrogel can not only realize antibacterial, and anti-inflammatory effects, but also promote angiogenesis to accelerate wound healing in vitro thanks to the composite PDA/Cu(H2O2) coatings. Significantly, CAC/PDA/Cu(H2O2) hydrogel illustrates excellent therapeutic effects in Methicillin-resistant Staphylococcus aureus (MRSA) induced-rat infection models, which can efficiently eliminate MRSA, dramatically reduce inflammatory expression, promote angiogenesis, and ultimately shorten the wound healing time. CAC/PDA/Cu(H2O2) hydrogel exhibited the best wound healing rate on days 7 (80.63 ± 2.44 %), 11 (92.45 ± 2.26 %), and 14 (97.86 ± 0.66 %). Thus, the multifunctional hydrogel provides a facile and efficient approach to wound management and represents promising potential in the therapy for wound healing.


Asunto(s)
Quitosano , Staphylococcus aureus Resistente a Meticilina , Ratas , Animales , Hidrogeles/farmacología , Quitosano/farmacología , Alginatos/farmacología , Peróxido de Hidrógeno/farmacología , Cicatrización de Heridas , Antibacterianos/farmacología , Vendajes
20.
Biotechnol Prog ; 38(4): e3256, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35384416

RESUMEN

Six kinds of Mo-basing nanomaterials (MoO3 , MoO3 @Ru, Mo-PDA, MoPC , MoP, CNT@MoS2 ) were successfully synthesized, which were employed as carriers to immobilize phospholipase A1 (PLA1) for the hydrolysis of phospholipids (PLs). PLA1 was immobilized by a simple adsorption-precipitation-cross-linking to form an "enzyme net" covering on nanoparticles. The greatest advantage of these nanoparticles was their strong hydrophilic surface. It not only permitted their dispersion in the aqueous phase, but also showed the strong affinity for PLs in the organic phase, because amphiphilic PLs had the polar head group and higher hydrophilicity than other oils components. Michaelis-Menten analysis revealed that higher catalytic activity and enzyme-substrate affinity were observed in several immobilized PLA1 than its free form. MoO3 was confirmed to be the best candidate for carrier. The highest specific activity of MoO3 -immobilized PLA1 reached 43.1 U/mg, which was about 1.8 times higher than that of free PLA1 (24.4 U/mg). In addition, the stability and recycling were also enhanced. The robust immobilized PLA1 was prepared in this work, showing great potential for the enzymatic degumming.


Asunto(s)
Nanoestructuras , Fosfolípidos , Enzimas Inmovilizadas , Hidrólisis , Interacciones Hidrofóbicas e Hidrofílicas , Fosfolipasas A1
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA