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1.
BMC Cancer ; 24(1): 269, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408928

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) can lead to life-threatening pneumonitis, and pre-existing interstitial lung abnormalities (ILAs) are a risk factor for checkpoint inhibitor pneumonitis (CIP). However, the subjective assessment of ILA and the lack of standardized methods restrict its clinical utility as a predictive factor. This study aims to identify non-small cell lung cancer (NSCLC) patients at high risk of CIP using quantitative imaging. METHODS: This cohort study involved 206 cases in the training set and 111 cases in the validation set. It included locally advanced or metastatic NSCLC patients who underwent ICI therapy. A deep learning algorithm labeled the interstitial lesions and computed their volume. Two predictive models were developed to predict the probability of grade ≥ 2 CIP or severe CIP (grade ≥ 3). Cox proportional hazard models were employed to analyze predictors of progression-free survival (PFS). RESULTS: In a training cohort of 206 patients, 21.4% experienced CIP. Two models were developed to predict the probability of CIP based on different predictors. Model 1 utilized age, histology, and preexisting ground glass opacity (GGO) percentage of the whole lung to predict grade ≥ 2 CIP, while Model 2 used histology and GGO percentage in the right lower lung to predict grade ≥ 3 CIP. These models were validated, and their accuracy was assessed. In another exploratory analysis, the presence of GGOs involving more than one lobe on pretreatment CT scans was identified as a risk factor for progression-free survival. CONCLUSIONS: The assessment of GGO volume and distribution on pre-treatment CT scans could assist in monitoring and manage the risk of CIP in NSCLC patients receiving ICI therapy. CLINICAL RELEVANCE STATEMENT: This study's quantitative imaging and computational analysis can help identify NSCLC patients at high risk of CIP, allowing for better risk management and potentially improved outcomes in those receivingICI treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neumonía , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Estudios de Cohortes , Pulmón/patología , Neumonía/patología , Tomografía Computarizada por Rayos X , Estudios Retrospectivos
2.
J Cell Mol Med ; 27(12): 1637-1652, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37226642

RESUMEN

KRAS mutation is the most frequent type of genetic mutation in non-small cell lung cancer (NSCLC), especially in lung adenocarcinoma. However, KRAS mutation can affect many biological processes and the mechanisms underlying KRAS mutation-mediate carcinogenesis in NSCLC have not been fully understood. In this research, we found that KRASG12C mutation was associated with the upregulation of T-LAK cell-originated protein kinase (TOPK), which is a well-known serine/threonine MAPK-like protein kinase implicated in tumorigenesis. The overexpression of TOPK significantly promoted the malignant phenotype of A549 cells, and TOPK silencing impaired the malignant phenotype with KRASG12C mutation. Moreover, we demonstrated that TOPK level was regulated by MAPK/ERK signalling and the transcription factor Elk1. TOPK was also found to promote the activation of NF-κB signalling in A549 cells with KRASG12C mutation via facilitating the phosphorylation of TAK1. In the in vivo tumorigenesis model, the administration of TOPK inhibitor OTS514 enhanced the anticancer effect of 5-FU, and the combinatory use of OTS514 and KRASG12C inhibitor AMG510 showed synergistic anti-tumour effect. These results suggest that KRAS-TOPK axis contributes to the progression of NSCLC and targeting this axis could synergize with anticancer effect of the existing chemotherapeutics.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinogénesis/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Células Asesinas Activadas por Linfocinas/metabolismo , Células Asesinas Activadas por Linfocinas/patología , Neoplasias Pulmonares/patología , Mutación/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo
3.
Molecules ; 28(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37764467

RESUMEN

To enhance the mechanical strength and cell adhesion of alginate hydrogel, making it satisfy the requirements of an ideal tissue engineering scaffold, the grafting of Arg-Gly-Asp (RGD) polypeptide sequence onto the alginate molecular chain was conducted by oxidation of sodium periodate and subsequent reduction amination of 2-methylpyridine borane complex (2-PBC) to synthesize alginate dialdehyde grafted RGD derivatives (ADA-RGD) with good cellular affinity. The interpenetrating network (IPN) composite hydrogels of alginate/polyvinyl alcohol/cellulose nanocrystals (ALG/PVA/CNCs) were fabricated through a physical mixture of ion cross-linking of sodium alginate (SA) with hydroxyapatite/D-glucono-δ-lactone (HAP/GDL), and physical cross-linking of polyvinyl alcohol (PVA) by a freezing/thawing method, using cellulose nanocrystals (CNCs) as the reinforcement agent. The effects of the addition of CNCs and different contents of PVA on the morphology, thermal stability, mechanical properties, swelling, biodegradability, and cell compatibility of the IPN composite hydrogels were investigated, and the effect of RGD grafting on the biological properties of the IPN composite hydrogels was also studied. The resultant IPN ALG/PVA/CNCs composite hydrogels exhibited good pore structure and regular 3D morphology, whose pore size and porosity could be regulated by adjusting PVA content and the addition of CNCs. By increasing the PVA content, the number of physical cross-linking points in PVA increased, resulting in greater stress support for the IPN composite hydrogels of ALG/PVA/CNCs and consequently improving their mechanical characteristics. The creation of the IPN ALG/PVA/CNCs composite hydrogels' physical cross-linking network through intramolecular or intermolecular hydrogen bonding led to improved thermal resistance and reduced swelling and biodegradation rate. Conversely, the ADA-RGD/PVA/CNCs IPN composite hydrogels exhibited a quicker degradation rate, attributed to the elimination of ADA-RGD by alkali. The results of the in vitro cytocompatibility showed that ALG/0.5PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels showed better proliferative activity in comparison with other composite hydrogels, while ALG/PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels displayed obvious proliferation effects, indicating that PVA, CNCs, and ADA-RGD with good biocompatibility were conducive to cell proliferation and differentiation for the IPN composite hydrogels.


Asunto(s)
Nanopartículas , Alcohol Polivinílico , Alcohol Polivinílico/química , Hidrogeles/química , Alginatos/química , Oligopéptidos , Celulosa/química
4.
Pediatr Transplant ; : e14367, 2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35860981

RESUMEN

BACKGROUND: Refractory/relapsed T-cell acute lymphoblastic leukemia (R/R T-ALL) is a hematological malignancy with a poor prognosis. The current treatment strategy has not benefited most patients, and the treatment methods are still being explored. CASE PRESENTATION: An 8-year-old boy with R/R T-ALL achieved CR after multiple chemotherapies, followed by the first allo-HSCT. Unfortunately, 1 year and 3 months later, he relapsed. After recurrence, the patient underwent multiple chemotherapies, but the NOTCH1 gene and MRD were still positive. FCM and immunohistochemistry revealed abnormally high expression of CD7, so we considered bridging the second allo-HSCT after CD7 CAR T-cells treatment. The patient has low toxic and side effects and is still in CR, findings from this case report have more important therapeutic significance for R/R T-ALL. CONCLUSION: In conclusion, CD7 CAR T-cells bridging to allo-HSCT is a safe and effective approach for R/R T-ALL, resulting in durable CR and longer survival.

5.
Support Care Cancer ; 30(8): 6515-6524, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35411466

RESUMEN

BACKGROUND AND AIM: Many pieces of literature have evaluated the predictive value of pre-existing lung interstitial changes for immunotherapy-related pneumonia in patients with non-small cell lung cancer (NSCLC), but the results of studies are still controversial. The purpose of this article is to explore whether pre-existing lung interstitial changes can predict the occurrence of immunotherapy-related pneumonia. METHODS: PubMed, Web of Science, and Embase were used to search for relevant documents. Two investigators respectively carried out literature screening, quality evaluation, and data extraction strictly according to the inclusion criteria. Odds ratios (ORs) and the corresponding 95% CIs were applied to assess the predictive value of interstitial lung disease (ILD), interstitial lung abnormalities (ILA), and radiation pneumonitis (RP). Stata 12.0 software was used for the statistical analysis of data. RESULTS: Seventeen studies involving 2758 patients were included in the final analysis. NSCLC patients with pulmonary interstitial changes were more likely to develop immune-related pneumonia after immunotherapy (OR = 3.68, 95% CI: 2.49-5.44). Subgroup analysis revealed that ILD (OR = 3.59, 95% CI: 2.22-5.82), RP (OR = 3.63, 95% CI: 1.80-7.30), and ILA (OR = 6.64, 95% CI: 1.78-24.8) were all predictors of immune-related pneumonia. As the preliminary screening of other risk factors, gender, neutrophilic lymphocyte ratio (NLR), actual eosinophil count (AEC), and drug type may have potential predictive value for immunotherapy-related pneumonia. There was no significant statistical heterogeneity and publication bias in our study. Further research is needed to update and validate our results. CONCLUSION: Pulmonary interstitial changes can be considered as a predictive factor of immune-related pneumonia after immunotherapy in NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Neumonía , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Humanos , Inmunoterapia/efectos adversos , Pulmón , Enfermedades Pulmonares Intersticiales/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Neumonía/complicaciones , Neumonía/etiología , Estudios Retrospectivos
6.
BMC Neurol ; 21(1): 55, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33546628

RESUMEN

BACKGROUND: Although several brain networks play important roles in cervical dystonia (CD) patients, regional homogeneity (ReHo) changes in CD patients have not been clarified. We investigated to explore ReHo in CD patients at rest and analyzed its correlations with symptom severity as measured by Tsui scale. METHODS: A total of 19 CD patients and 21 gender-, age-, and education-matched healthy controls underwent fMRI scans at rest state. Data were analyzed by ReHo method. RESULTS: Patients showed increased ReHo in the right cerebellum crus I and decreased ReHo in the right superior medial prefrontal cortex (MPFC). Moreover, the right precentral gyrus, right insula, and bilateral middle cingulate gyrus also showed increased ReHo values. A significantly positive correlation was observed between ReHo value in the right cerebellum crus I and symptom severity (p < 0.05). CONCLUSIONS: Our investigation suggested abnormal ReHo existed in brain regions of the "pain matrix" and salience network (the right insula and bilateral middle cingulate gyrus), the motor network (the right precentral gyrus), the cerebellum and MPFC and further highlighted the significance of these networks in the pathology of CD.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/patología , Tortícolis/diagnóstico por imagen , Tortícolis/patología , Adulto , Mapeo Encefálico/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad
7.
Molecules ; 26(19)2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34641365

RESUMEN

On account of the rigid structure of alginate chains, the oxidation-reductive amination reaction was performed to synthesize the reductive amination of oxidized alginate derivative (RAOA) that was systematically characterized for the development of pharmaceutical formulations. The molecular structure and self-assembly behavior of the resultant RAOA was evaluated by an FT-IR spectrometer, a 1H NMR spectrometer, X-ray diffraction (XRD), thermal gravimetric analysis (TGA), a fluorescence spectrophotometer, rheology, a transmission electron microscope (TEM) and dynamic light scattering (DLS). In addition, the loading and in vitro release of ibuprofen for the RAOA microcapsules prepared by the high-speed shearing method, and the cytotoxicity of the RAOA microcapsules against the murine macrophage RAW264.7 cell were also studied. The experimental results indicated that the hydrophobic octylamine was successfully grafted onto the alginate backbone through the oxidation-reductive amination reaction, which destroyed the intramolecular hydrogen bond of the raw sodium alginate (SA), thereby enhancing its molecular flexibility to achieve the self-assembly performance of RAOA. Consequently, the synthesized RAOA displayed good amphiphilic properties with a critical aggregation concentration (CAC) of 0.43 g/L in NaCl solution, which was significantly lower than that of SA, and formed regular self-assembled micelles with an average hydrodynamic diameter of 277 nm (PDI = 0.19) and a zeta potential of about -69.8 mV. Meanwhile, the drug-loaded RAOA microcapsules had a relatively high encapsulation efficiency (EE) of 87.6 % and good sustained-release properties in comparison to the drug-loaded SA aggregates, indicating the good affinity of RAOA to hydrophobic ibuprofen. The swelling and degradation of RAOA microcapsules and the diffusion of the loaded drug jointly controlled the release rate of ibuprofen. Moreover, it also displayed low cytotoxicity against the RAW264.7 cell, similar to the SA aggregates. In view of the excellent advantages of RAOA, it is expected to become the ideal candidate for hydrophobic drug delivery in the biomedical field.


Asunto(s)
Alginatos/química , Aminas/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Ibuprofeno/administración & dosificación , Macrófagos/efectos de los fármacos , Aminación , Animales , Ibuprofeno/química , Ratones , Micelas , Estructura Molecular , Células RAW 264.7
8.
Molecules ; 26(16)2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34443588

RESUMEN

It is common knowledge that pure alginate hydrogel is more likely to have weak mechanical strength, a lack of cell recognition sites, extensive swelling and uncontrolled degradation, and thus be unable to satisfy the demands of the ideal scaffold. To address these problems, we attempted to fabricate alginate/bacterial cellulose nanocrystals-chitosan-gelatin (Alg/BCNs-CS-GT) composite scaffolds using the combined method involving the incorporation of BCNs in the alginate matrix, internal gelation through the hydroxyapatite-d-glucono-δ-lactone (HAP-GDL) complex, and layer-by-layer (LBL) electrostatic assembly of polyelectrolytes. Meanwhile, the effect of various contents of BCNs on the scaffold morphology, porosity, mechanical properties, and swelling and degradation behavior was investigated. The experimental results showed that the fabricated Alg/BCNs-CS-GT composite scaffolds exhibited regular 3D morphologies and well-developed pore structures. With the increase in BCNs content, the pore size of Alg/BCNs-CS-GT composite scaffolds was gradually reduced from 200 µm to 70 µm. Furthermore, BCNs were fully embedded in the alginate matrix through the intermolecular hydrogen bond with alginate. Moreover, the addition of BCNs could effectively control the swelling and biodegradation of the Alg/BCNs-CS-GT composite scaffolds. Furthermore, the in vitro cytotoxicity studies indicated that the porous fiber network of BCNs could fully mimic the extracellular matrix structure, which promoted the adhesion and spreading of MG63 cells and MC3T3-E1 cells on the Alg/BCNs-CS-GT composite scaffolds. In addition, these cells could grow in the 3D-porous structure of composite scaffolds, which exhibited good proliferative viability. Based on the effect of BCNs on the cytocompatibility of composite scaffolds, the optimum BCNs content for the Alg/BCNs-CS-GT composite scaffolds was 0.2% (w/v). On the basis of good merits, such as regular 3D morphology, well-developed pore structure, controlled swelling and biodegradation behavior, and good cytocompatibility, the Alg/BCNs-CS-GT composite scaffolds may exhibit great potential as the ideal scaffold in the bone tissue engineering field.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Celulosa/química , Quitosano/química , Gelatina/química , Nanocompuestos/química , Nanopartículas/química , Células 3T3 , Animales , Materiales Biocompatibles/farmacología , Adhesión Celular/efectos de los fármacos , Ratones , Porosidad
9.
Mol Phylogenet Evol ; 141: 106633, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31563612

RESUMEN

Using numerical methods for genome comparison has always been of importance in bioinformatics. The Chaos Game Representation (CGR) is an effective genome sequence mapping technology, which converts genome sequences to CGR images. To each CGR image, we associate a vector called an Extended Natural Vector (ENV). The ENV is based on the distribution of intensity values. This mapping produces a one-to-one correspondence between CGR images and their ENVs. We define the distance between two DNA sequences as the distance between their associated ENVs. We cluster and classify several datasets including Influenza A viruses, Bacillus genomes, and Conoidea mitochondrial genomes to build their phylogenetic trees. Results show that our ENV combining CGR method (CGR-ENV) compares favorably in classification accuracy and efficiency against the multiple sequence alignment (MSA) method and other alignment-free methods. The research provides significant insights into the study of phylogeny, evolution, and efficient DNA comparison algorithms for large genomes.


Asunto(s)
Algoritmos , Genoma , Genómica , Secuencia de Bases , ADN/genética , Genoma Mitocondrial , Cadenas de Markov , Filogenia
10.
Sheng Li Xue Bao ; 68(5): 691-698, 2016 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-27778036

RESUMEN

The aim of the present study was to obtain the qualified hematopoietic stem/progenitor cells (HSC/HPC) and human umbilical cord-mesenchymal stem cells (MSC) in vitro in the co-culture system. Cord blood mononuclear cells were separated from umbilical cord blood by Ficoll lymphocyte separation medium, and then CD34+ HSC was collected by MACS immunomagnetic beads. The selected CD34+ HSC/HPC and MSC were transferred into culture flask. IMDM culture medium with 15% AB-type cord plasma supplemented with interleukin-3 (IL-3), IL-6, thrombopoietin (TPO), stem cell factor (SCF) and FMS-like tyrosine kinase 3 ligand (Flt-3L) factors were used as the co-culture system for the amplification of HSC/HPC and MSC. The cellular growth status and proliferation on day 6 and 10 after co-culture were observed by using inverted microscope. The percentage of positive expression of CD34 in HSC/HPC, as well as the percentages of positive expressions of CD105, CD90, CD73, CD45, CD34 and HLA-DR in the 4th generation MSC, was tested by flow cytometry. Semisolid colony culture was used to test the HSC/HPC colony forming ability. The osteogenic, chondrogenesis and adipogenic ability of the 4th generation MSC were assessed. The karyotype analysis of MSC was conducted by colchicines. The results demonstrated that the HSC/HPC of co-culture group showed higher ability of amplification, CFU-GM and higher CD34+ percentage compared with the control group. The co-cultured MSC maintained the ability to differentiate into bone cells, fat cells and chondrocytes. And the karyotype stability of MSC remained normal. These results reveal that the appropriate co-culture system for MSC and HSC is developed, and via this co-culture system we could gain both two kinds of these cells. The MSCs under the co-culture system maintain the biological characteristics. The CFU-GM ability, cell counting and the flow cytometry results of HSC/HPC under the co-culture system are conform to the criterion, showing that the biological functions of HSC/HPC are maintained.


Asunto(s)
Células Madre Hematopoyéticas , Células Madre Mesenquimatosas , Antígenos CD34 , Técnicas de Cultivo de Célula , Proliferación Celular , Células Cultivadas , Técnicas de Cocultivo , Sangre Fetal , Citometría de Flujo , Humanos , Interleucina-3 , Interleucina-6 , Factor de Células Madre , Cordón Umbilical , Tirosina Quinasa 3 Similar a fms
11.
Int J Biol Macromol ; 257(Pt 2): 128653, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38072345

RESUMEN

The application of hydrophobic ß-carotene in the food industry are limited due to its susceptibility to light, high temperature, pH value, and other factors, leading to poor stability and low bioavailability. To address this problem, we adopt a more green and environmentally friendly reducing agent, 2-methylpyridine borane complex (pic-BH3), instead of traditional sodium borohydride, to achieve the simple green and efficient synthesis of amphiphilic oxidized sodium alginate grafted oleoamine derivatives (OSAOLA) through the reduction amination reaction of Schiff base. The resultant OSAOLA with the degree of substitution (DS) of 7.2 %, 23.6 %, and 38.8 % were synthesized, and their CMC values ranged from 0.0095 to 0.062 mg/mL, indicating excellent self-assembly capability in aqueous solution. Meanwhile, OSAOLA showed no obvious cytotoxicity to RAW 264.7 cells, thus revealing good biocompatibility. Furthermore, ß-carotene, as the hydrophobic active ingredients in foods was successfully encapsulated in the OSAOLA micelles by ultrasonic-dialysis method. The prepared drug-loaded OSAOLA micelles could maintain good stability when stored at room temperature for 7 d. Additionally, they were able to continuously release ß-carotene and exert long-term effects in pH 7.4 PBS at 37 °C, effectively improving the bioavailability of ß-carotene, which exhibited tremendous application potential in functional food and biomedical fields.


Asunto(s)
Ingredientes Alimentarios , Micelas , Alginatos , beta Caroteno/química , Aminación , Bases de Schiff , Diálisis Renal , Portadores de Fármacos/química
12.
J Thorac Dis ; 15(4): 1958-1969, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37197523

RESUMEN

Background: Recent studies have reported that the combination of immune checkpoint inhibitors (ICIs) and antiangiogenic agents could be a promising therapeutic strategy for advanced non-small cell lung cancer (NSCLC). However, both ICIs and antiangiogenic agents are associated with endocrine dysfunctions, mainly hypothyroidism. The risk of hypothyroidism is potentially increased with the combination of ICIs and antiangiogenic agents. This study aimed to investigate the incidence and risk factors of hypothyroidism in patients receiving combination therapy. Methods: We performed a retrospective cohort study of advanced NSCLC patients treated with ICIs and antiangiogenic agents at Tianjin Medical University Cancer Institute & Hospital from July 1, 2019, to December 31, 2021. Patients with normal thyroid function at baseline were enrolled, and information on the patients' characteristics before receiving combination therapy, including body mass index (BMI) and laboratory data, was obtained. Results: Among the 137 enrolled patients, 39 (28.5%) developed new-onset hypothyroidism, and 20 (14.6%) developed overt hypothyroidism. The incidence of hypothyroidism was significantly higher in obese patients than in patients with a low to normal BMI (P<0.001). Obese patients also had a higher incidence of overt hypothyroidism (P=0.016). Univariate logistic regression showed that BMI as a continuous variable was a significant risk factor for hypothyroidism [odds ratio (OR) 1.24, 95% confidence interval (CI): 1.10-1.42, P<0.001] and overt hypothyroidism (OR 1.17, 95% CI: 1.01-1.38, P=0.039). Multivariate logistic regression revealed that only BMI (OR 1.36, 95% CI: 1.16-1.61, P<0.001) and age (OR 1.08, 95% CI: 1.02-1.14, P=0.006) were significant risk factors for treatment-related hypothyroidism. Conclusions: The risk of hypothyroidism in patients receiving a combination of ICIs and antiangiogenic therapy is manageable, and a higher BMI is associated with a significantly increased risk of hypothyroidism. Therefore, clinicians should be aware of the development of hypothyroidism in obese advanced NSCLC patients during the administration of ICIs combined with antiangiogenic agents.

13.
IEEE Trans Neural Netw Learn Syst ; 34(10): 7992-8006, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35171782

RESUMEN

In this article, we investigate the approximation ability of recurrent neural networks (RNNs) with stochastic inputs in state space model form. More explicitly, we prove that open dynamical systems with stochastic inputs can be well-approximated by a special class of RNNs under some natural assumptions, and the asymptotic approximation error has also been delicately analyzed as time goes to infinity. In addition, as an important application of this result, we construct an RNN-based filter and prove that it can well-approximate finite dimensional filters which include Kalman filter (KF) and Benes filter as special cases. The efficiency of RNN-based filter has also been verified by two numerical experiments compared with optimal KF.

14.
Colloids Surf B Biointerfaces ; 228: 113413, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37343505

RESUMEN

Alginate (Alg) hydrogels possess desirable advantages for application in tissue engineering; however, they are limited by their weak mechanical properties, poor chronical stability in phosphate buffered saline, and absence of mammalian cell recognition sites, severely restricting their biomedical applications. To overcome these limitations, we integrated Alg hydrogels with nano-silica (SiO2) to produce nano-SiO2 reinforced Alg-chitosan-gelatin nanocomposite hydrogels (Alg/SiO2-CHI-GA NCH) for biomedical purposes, utilizing Chitosan (CHI) and gelatin (GA) in an alternate electrostatic adsorption. Specifically, we investigated the regulatory and promotional effects of the nano-SiO2 on the morphological structure, mechanical properties, thermal stability, rheological properties, swelling, biodegradability, biomineralization and cytocompatibility of the resultant Alg/SiO2-CHI-GA NCH. The experimental findings demonstrate that the constructed Alg/SiO2-CHI-GA NCH exhibited uniform morphology and a regular structure. Upon freeze-drying, the internal cross-sections of the NCH exhibited a honeycomb porous structure. Furthermore, the physicochemical properties and biological activities of the prepared Alg/SiO2-CHI-GA NCH were regulated to some extent by nano-SiO2 content. Notably, nano-SiO2 inclusion enhanced the attachment and viability of MG63 and MC3T3-E1 cells and induced three-dimensional cell growth in ALG/SiO2-CHI-GA NCH. Among the fabricated NCH, Alg/SiO2-CHI-GA NCH with 0.5% and 1.0% (w/v) nano-SiO2 exhibited significant proliferative activity, which is attributable to their high porosity and uniform cell adhesion. Furthermore, the alkaline phosphatase activity in the cells gradually increased with increasing of nano-SiO2 amount, indicating the favorable effect of nano-SiO2 on the osteogenic differentiation of MG63 and MC3T3-E1 cells. Our study findings provide a comprehensive foundation for the structural- and property-related limitations of Alg hydrogels in biomedicine, thereby expanding their potential applications in tissue engineering.


Asunto(s)
Quitosano , Animales , Quitosano/química , Alginatos/química , Gelatina/farmacología , Nanogeles , Osteogénesis , Dióxido de Silicio/química , Ingeniería de Tejidos/métodos , Hidrogeles/farmacología , Hidrogeles/química , Andamios del Tejido/química , Mamíferos
15.
J Cancer Res Clin Oncol ; 149(13): 11041-11055, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37338641

RESUMEN

BACKGROUND AND AIM: According to previous reports, GTPase of immunity-associated protein 6 (GIMAP6) is essential for autophagy. However, it is unclear how GIMAP6 affects the development and tumor immunity of lung adenocarcinoma (LUAD). METHODS: In the present study, the role of GIMAP6 in vivo and in vitro was examined using reverse transcription-quantitative PCR, western blotting, and Cell Counting Kit-8, colony formation and Transwell assays. Datasets from The Cancer Genome Atlas and Genotype-Tissue Expression databases were thoroughly analyzed using R software. A nomogram was created using GIMAP6 and prognostic characteristics. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and Gene Set Enrichment Analysis were applied to explore the potential mechanism of GIMAP6 in lung cancer. The link between GIMAP6 and the immunological landscape was studied using single-cell RNA sequencing datasets from Tumor Immune Estimation Resource (TIMER) 2.0 and Tumor Immune Single-cell Hub. RESULTS: Patients with high GIMAP6 expression had improved overall and disease-specific survival compared with those patients with low GIMAP6 expression. According to the receiver operating characteristic and calibration curve, the nomogram based on T stage, N stage and GIMAP6 had predictive value for prognosis. According to functional enrichment analysis, GIMAP6 was primarily involved in T-cell receptor signaling pathway, chemokine signaling pathway, cytokine and cytokine receptor interaction. GIMAP6 was shown to be favorably linked with the infiltration of immune cells and immune-related molecules, including cytotoxic T-lymphocyte associated protein 4, programmed death-ligand 1, and T cell immunoreceptor with Ig and ITIM domains, by single-cell sequencing and TIMER2.0 analysis. The role of GIMAP6 in lung cancer cell proliferation, invasion, migration and immunity was experimentally verified. CONCLUSION: These findings confirmed that GIMAP6 was an effective prognostic molecule that was involved in the regulation of the immune microenvironment of LUAD, and may become a predictor for the efficacy of immunotherapy.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , GTP Fosfohidrolasas , Pronóstico , Biomarcadores , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/genética , Microambiente Tumoral/genética
16.
Front Genet ; 14: 1160915, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37077542

RESUMEN

Background: Lung adenocarcinoma (LUAD) is an aggressive disease of heterogeneous characteristics with poor prognosis and high mortality. Pyroptosis, a newly uncovered type of programmed cell death with an inflammatory nature, has been determined to hold substantial importance in the progression of tumors. Despite this, the knowledge about pyroptosis-related genes (PRGs) in LUAD is limited. This study aimed to develop and validate a prognostic signature for LUAD based on PRGs. Methods: In this research, gene expression information from The Cancer Genome Atlas (TCGA) served as the training cohort and data from Gene Expression Omnibus (GEO) was utilized as the validation cohort. PRGs list was taken from the Molecular Signatures Database (MSigDB) and previous studies. Univariate Cox regression and Lasso analysis were then conducted to identify prognostic PRGs and develop a LUAD prognostic signature. The Kaplan-Meier method, univariate and multivariate Cox regression models were employed to assess the independent prognostic value and forecasting accuracy of the pyroptosis-related prognostic signature. The correlation between prognostic signature and immune infiltrating was analyzed to examine the role in tumor diagnosis and immunotherapy. Further, RNA-seq as well as quantitative real-time polymerase chain reaction (qRT-PCR) analysis in separate data sets was applied in order to validate the potential biomarkers for LUAD. Results: A novel prognostic signature based on 8 PRGs (BAK1, CHMP2A, CYCS, IL1A, CASP9, NLRC4, NLRP1, and NOD1) was established to predict the survival of LUAD. The prognostic signature proved to be an independent prognostic factor of LUAD with satisfactory sensitivity and specificity in the training and validation sets. High-risk scores subgroups in the prognostic signature were significantly associated with advanced tumor stage, poor prognosis, less immune cell infiltration, and immune function deficiency. RNA sequencing and qRT-PCR analysis confirmed that the expression of CHMP2A and NLRC4 could be used as biomarkers for LUAD. Conclusion: We have successfully developed a prognostic signature consisting of eight PRGs that providing a novel perspective on predicting prognosis, assessing infiltration levels of tumor immune cells, and determining the outcomes of immunotherapy for LUAD.

17.
Cancer Pathog Ther ; 1(4): 238-252, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38327603

RESUMEN

Background: Nucleophosmin/nucleoplasmin 3 (NPM3), a member of the NPM protein family, is widely expressed in various human tissues. Although previous studies identified elevated NPM3 expression in several cancers, a systematic pan-cancer analysis remains lacking. In this study, we conducted a comprehensive analysis of NPM3 to determine its role in tumorigenesis and tumor development. Methods: Using data from The Cancer Genome Atlas (TCGA) and various bioinformatics analysis tools, we conducted a pan-cancer analysis of NPM3. Additionally, we collected gene expression and clinical data from 890 patients with lung adenocarcinoma (LUAD) from TCGA and the Gene Expression Omnibus database. We performed Cox regression analyses to explore the independent prognostic value of NPM3 expression in LUAD and plotted a nomogram to predict patient survival. We also used real-time quantitative polymerase chain reaction (RT-qPCR) to examine the expression levels of NPM3 in seven pairs of LUAD and paraneoplastic tissue samples. Results: NPM3 expression was significantly increased in 20 types of cancer and was associated with poor prognosis in five types (P < 0.05). NPM3 expression was negatively correlated with DNA methylation and positively correlated with copy number variation. NPM3 was also significantly associated with immune cell infiltration in various cancers. Cox regression analyses revealed that NPM3 expression could serve as an independent prognostic marker of LUAD. Moreover, our nomogram demonstrated good predictive ability for the prognosis of patients with LUAD. Finally, the high expression of NPM3 in LUAD was verified using RT-qPCR. Conclusion: NPM3 is a promising biomarker for predicting pan-cancer prognosis and immunotherapeutic efficacy.

18.
Gels ; 8(12)2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36547323

RESUMEN

Alginate hydrogel commonly suffers from defects, such as weak mechanical properties, the shortage of long-term stability in physiological medium and the lack of mammalian cell adhesivity due to its strong hydrophilicity in biomedical application. For this reason, the homogeneous alginate hydrogels (Alg Gel) were successfully prepared by the D-glucono-δ-lactone/hydroxyapatite (HAP/GDL) cross-linking system, and then, the physical blending and alternating electrostatic assembly technology were proposed to fabricate alginate composite hydrogels (Alg-GT, Alg-CS-GT and ALG/GT-CS). The feasibility of the design methods was verified through the comparative analysis of their physicochemical properties and biological activity. In particular, the effects of physical blending and alternating electrostatic assembly technology on the pore structure, mechanical properties, swelling, degradation, cell adhesion and proliferation of composite hydrogels were also investigated. Experimental results showed that the formation of polyelectrolyte complexes by electrostatic assembly between biological macromolecules and the covalent cross-linking of EDC/NHS to GT improved the vulnerability of ion cross-linking, enhanced the mechanical properties and swelling stability of the composite hydrogels, and regulated their pore structure and in vitro biodegradability properties. Furthermore, MC3T3-E1 cells could exhibit good cell adhesion, cell viability and cell proliferation on the alginate composite hydrogels. Among them, Alg-CS-GT showed the best cell proliferation ability and differentiation effect due to its good cell adhesion. In view of the excellent physicochemical properties and biological activity of Alg-CS-GT, it exhibited great potential in biomedical application for tissue engineering.

19.
Polymers (Basel) ; 14(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35566849

RESUMEN

Oxidized sodium alginate (OSA) is selected as an appropriate material to be extensively applied in regenerative medicine, 3D-printed/composite scaffolds, and tissue engineering for its excellent physicochemical properties and biodegradability. However, few literatures have systematically investigated the structure and properties of the resultant OSA and the effect of the oxidation degree (OD) of alginate on its biodegradability and gelation ability. Herein, we used NaIO4 as the oxidant to oxidize adjacent hydroxyl groups at the C-2 and C-3 positions on alginate uronic acid monomer to obtain OSA with various ODs. The structure and physicochemical properties of OSA were evaluated by Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (1H NMR), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), and thermogravimetric analysis (TGA). At the same time, gel permeation chromatography (GPC) and a rheometer were used to determine the hydrogel-forming ability and biodegradation performance of OSA. The results showed that the two adjacent hydroxyl groups of alginate uronic acid units were successfully oxidized to form the aldehyde groups; as the amount of NaIO4 increased, the OD of OSA gradually increased, the molecular weight decreased, the gelation ability continued to weaken, and degradation performance obviously rose. It is shown that OSA with various ODs could be prepared by regulating the molar ratio of NaIO4 and sodium alginate (SA), which could greatly broaden the application of OSA-based hydrogel in tissue engineering, controlled drug release, 3D printing, and the biomedical field.

20.
Polymers (Basel) ; 14(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35215606

RESUMEN

In this paper, we developed an organic solvent-free, eco-friendly, simple and efficient one-pot approach for the preparation of amphiphilic conjugates (Ugi-OSAOcT) by grafting octylamine (OCA) to oxidized sodium alginate (OSA). The optimum reaction parameters that were obtained based on the degree of substitution (DS) of Ugi-OSAOcT were a reaction time of 12 h, a reaction temperature of 25 °C and a molar ratio of 1:2.4:3:3.3 (OSA:OCA:HAc:TOSMIC), respectively. The chemical structure and composition were characterized by Fourier transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance (1H NMR), X-ray diffraction (XRD), thermogravimetry analyser (TGA), gel permeation chromatography (GPC) and elemental analysis (EA). It was found that the Ugi-OSAOcT conjugates with a CMC value in the range of 0.30-0.085 mg/mL could self-assemble into stable and spherical micelles with a particle size of 135.7 ± 2.4-196.5 ± 3.8 nm and negative surface potentials of -32.8 ± 0.4--38.2 ± 0.8 mV. Furthermore, ibuprofen (IBU), which served as a model poorly water-soluble drug, was successfully incorporated into the Ugi-OSAOcT micelles by dialysis method. The drug loading capacity (%DL) and encapsulation efficiency (%EE) of the IBU-loaded Ugi-OSAOcT micelles (IBU/Ugi-OSAOcT = 3:10) reached as much as 10.9 ± 0.4-14.6 ± 0.3% and 40.8 ± 1.6-57.2 ± 1.3%, respectively. The in vitro release study demonstrated that the IBU-loaded micelles had a sustained and pH-responsive drug release behavior. In addition, the DS of the hydrophobic segment on an OSA backbone was demonstrated to have an important effect on IBU loading and drug release behavior. Finally, the in vitro cytotoxicity assay demonstrated that the Ugi-OSAOcT conjugates exhibited no significant cytotoxicity against RAW 264.7 cells up to 1000 µg/mL. Therefore, the amphiphilic Ugi-OSAOcT conjugates synthesized by the green method exhibited great potential to load hydrophobic drugs, acting as a promising nanocarrier capable of responding to pH for sustained release of hydrophobic drugs.

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