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1.
World J Gastrointest Oncol ; 16(4): 1465-1478, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660658

RESUMO

BACKGROUND: Colorectal cancer has a low 5-year survival rate and high mortality. Human ß-defensin-1 (hBD-1) may play an integral function in the innate immune system, contributing to the recognition and destruction of cancer cells. Long non-coding RNAs (lncRNAs) are involved in the process of cell differentiation and growth. AIM: To investigate the effect of hBD-1 on the mammalian target of rapamycin (mTOR) pathway and autophagy in human colon cancer SW620 cells. METHODS: CCK8 assay was utilized for the detection of cell proliferation and determination of the optimal drug concentration. Colony formation assay was employed to assess the effect of hBD-1 on SW620 cell proliferation. Bioinformatics was used to screen potentially biologically significant lncRNAs related to the mTOR pathway. Additionally, p-mTOR (Ser2448), Beclin1, and LC3II/I expression levels in SW620 cells were assessed through Western blot analysis. RESULTS: hBD-1 inhibited the proliferative ability of SW620 cells, as evidenced by the reduction in the colony formation capacity of SW620 cells upon exposure to hBD-1. hBD-1 decreased the expression of p-mTOR (Ser2448) protein and increased the expression of Beclin1 and LC3II/I protein. Furthermore, bioinformatics analysis identified seven lncRNAs (2 upregulated and 5 downregulated) related to the mTOR pathway. The lncRNA TCONS_00014506 was ultimately selected. Following the inhibition of the lncRNA TCONS_00014506, exposure to hBD-1 inhibited p-mTOR (Ser2448) and promoted Beclin1 and LC3II/I protein expression. CONCLUSION: hBD-1 inhibits the mTOR pathway and promotes autophagy by upregulating the expression of the lncRNA TCONS_00014506 in SW620 cells.

2.
Gut ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684238

RESUMO

OBJECTIVE: Mutations in presenilin genes are the major cause of Alzheimer's disease. However, little is known about their expression and function in the gut. In this study, we identify the presenilins Psen1 and Psen2 as key molecules that maintain intestinal homoeostasis. DESIGN: Human inflammatory bowel disease (IBD) and control samples were analysed for Psen1 expression. Newly generated intestinal epithelium-specific Psen1-deficient, Psen2-deficient and inducible Psen1/Psen2 double-deficient mice were used to dissect the functional role of presenilins in intestinal homoeostasis. RESULTS: Psen1 expression was regulated in experimental gut inflammation and in patients with IBD. Induced deletion of Psen1 and Psen2 in mice caused rapid weight loss and spontaneous development of intestinal inflammation. Mice exhibited epithelial barrier disruption with bacterial translocation and deregulation of key pathways for nutrient uptake. Wasting disease was independent of gut inflammation and dysbiosis, as depletion of microbiota rescued Psen-deficient animals from spontaneous colitis development but not from weight loss. On a molecular level, intestinal epithelial cells lacking Psen showed impaired Notch signalling and dysregulated epithelial differentiation. CONCLUSION: Overall, our study provides evidence that Psen1 and Psen2 are important guardians of intestinal homoeostasis and future targets for barrier-promoting therapeutic strategies in IBD.

3.
Neural Netw ; 173: 106201, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447305

RESUMO

Spatial prediction tasks are challenging when observed samples are sparse and prediction samples are abundant. Gaussian processes (GPs) are commonly used in spatial prediction tasks and have the advantage of measuring the uncertainty of the interpolation result. However, as the sample size increases, GPs suffer from significant overhead. Standard neural networks (NNs) provide a powerful and scalable solution for modeling spatial data, but they often overfit small sample data. Based on conditional neural processes (CNPs), which combine the advantages of GPs and NNs, we propose a new framework called Spatial Multi-Attention Conditional Neural Processes (SMACNPs) for spatial small sample prediction tasks. SMACNPs are a modular model that can predict targets by employing different attention mechanisms to extract relevant information from different forms of sample data. The task representation is inferred by measuring the spatial correlation contained in different sample points and the relationship contained in attribute variables, respectively. The distribution of the target variable is predicted by GPs parameterized by NNs. SMACNPs allow us to obtain accurate predictions of the target value while quantifying the prediction uncertainty. Experiments on spatial prediction tasks on simulated and real-world datasets demonstrate that this framework flexibly incorporates spatial context and correlation into the model, achieving state-of-the-art results in spatial small sample prediction tasks in terms of both predictive performance and reliability. For example, on the California housing dataset, our method reduces MAE by 8% and MSE by 7% compared to the second-best method. In addition, a spatiotemporal prediction task to forecast traffic speed further confirms the effectiveness and generality of our method.


Assuntos
Redes Neurais de Computação , Reprodutibilidade dos Testes , Incerteza
4.
Front Genet ; 15: 1361952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495668

RESUMO

Introduction: The global headlines have been dominated by the sudden and widespread outbreak of monkeypox, a rare and endemic zoonotic disease caused by the monkeypox virus (MPXV). Genomic composition based machine learning (ML) methods have recently shown promise in identifying host adaptability and evolutionary patterns of virus. Our study aimed to analyze the genomic characteristics and evolutionary patterns of MPXV using ML methods. Methods: The open reading frame (ORF) regions of full-length MPXV genomes were filtered and 165 ORFs were selected as clusters with the highest homology. Unsupervised machine learning methods of t-distributed stochastic neighbor embedding (t-SNE), Principal Component Analysis (PCA), and hierarchical clustering were performed to observe the DCR characteristics of the selected ORF clusters. Results: The results showed that MPXV sequences post-2022 showed an obvious linear adaptive evolution, indicating that it has become more adapted to the human host after accumulating mutations. For further accurate analysis, the ORF regions with larger variations were filtered out based on the ranking of homology difference to narrow down the key ORF clusters, which drew the same conclusion of linear adaptability. Then key differential protein structures were predicted by AlphaFold 2, which meant that difference in main domains might be one of the internal reasons for linear adaptive evolution. Discussion: Understanding the process of linear adaptation is critical in the constant evolutionary struggle between viruses and their hosts, playing a significant role in crafting effective measures to tackle viral diseases. Therefore, the present study provides valuable insights into the evolutionary patterns of the MPXV in 2022 from the perspective of genomic composition characteristics analysis through ML methods.

5.
Cell Death Dis ; 13(1): 52, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022391

RESUMO

SMYD2 is a histone methyltransferase, which methylates both histone H3K4 as well as a number of non-histone proteins. Dysregulation of SMYD2 has been associated with several diseases including cancer. In the present study, we investigated whether and how SMYD2 might contribute to colorectal cancer. Increased expression levels of SMYD2 were detected in human and murine colon tumor tissues compared to tumor-free tissues. SMYD2 deficiency in colonic tumor cells strongly decreased tumor growth in two independent experimental cancer models. On a molecular level, SMYD2 deficiency sensitized colonic tumor cells to TNF-induced apoptosis and necroptosis without affecting cell proliferation. Moreover, we found that SMYD2 targeted RIPK1 and inhibited the phosphorylation of RIPK1. Finally, in a translational approach, pharmacological inhibition of SMYD2 attenuated colonic tumor growth. Collectively, our data show that SMYD2 is crucial for colon tumor growth and inhibits TNF-induced apoptosis and necroptosis.


Assuntos
Neoplasias do Colo , Necroptose , Animais , Apoptose , Neoplasias do Colo/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Humanos , Camundongos , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
6.
Chin J Dent Res ; 24(1): 41-47, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33890454

RESUMO

OBJECTIVE: To develop a novel chondrocyte condensation culture strategy recapitulating developmental condensation and construct self-organised cartilaginous tissue for cartilage regeneration. METHODS: Cell-condensation aggregate (CCA) was generated using the condensation culture method by sequential cell seeding. The chondrification capacities and biocompatibilities of CCA were assessed by comparison with the cell-scaffold complex (CSC), which was constructed by cell-scaffold coculture. Preclinical studies including implantation into nude mice subcutaneously and cartilage defect repair in rabbits were performed. RESULTS: CCA constructed by condensation culture exhibited a morphology of self-organised cartilaginous tissue. Meanwhile, the condensation culture inhibited or abolished expression of HOX genes including HOXC4 and HOXD8, which was partially consistent with developmental HOX gene expression patterns and associated with enhanced regeneration capacities. Compared with CSC, CCA showed a higher capacity for chondrification and regeneration of rabbit cartilage defects. CONCLUSION: The therapeutic assessments indicate that CCA is an efficient therapeutic tool for cartilage regeneration, providing a new strategy for tissue engineering by mimicking developmental events.


Assuntos
Cartilagem Articular , Animais , Condrócitos , Camundongos , Camundongos Nus , Coelhos , Regeneração , Engenharia Tecidual , Alicerces Teciduais
7.
Zhonghua Nan Ke Xue ; 26(2): 160-166, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33346421

RESUMO

OBJECTIVE: To investigate the protective effect of Jinkui Shenqi Pills (JSP) against cyclophosphamide-induced testis injury (TI) and its anti-oxidation mechanism in mice. METHODS: Thirty male mice were equally divided into a blank control, a TI model control and a JSP treatment group. The mice in the JSP treatment group were treated intragastrically with JSP and the blank controls with normal saline at 1.2 g/kg qd for 7 days, and then the animals in both the TI model control and JSP treatment groups were injected intraperitoneally with cyclophosphamide at 50 mg/kg, once a week, for 35 days, to induce testis injury. After modeling, all the mice were weighed and sacrificed, followed by detection of the serum T content, measurement of the testis weight, examination of semen parameters in the caudad epididymis, and determination of the levels of super oxide dismutase (SOD) and malondialdehyde (MDA) in the testis tissue and the expressions of relevant genes by qRT-PCR. RESULTS: The mice of the TI model control group, compared with the blank controls, showed significant decreases in the body weight (ï¼»34.63 ± 1.92ï¼½ vs ï¼»48.32 ± 1.64ï¼½ g, P<0.05), testis weight (ï¼»80.00 ± 3.90ï¼½ vs ï¼»140.00 ± 6.10ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.22 ± 0.01ï¼½ vs ï¼»0.31 ±0.03ï¼½%, P<0.05), sperm motility (ï¼»48.66 ± 8.08ï¼½% vs ï¼»89.33 ± 4.04ï¼½%, P<0.05), sperm concentration (ï¼»28.42 ± 5.26ï¼½ vs ï¼»77.67 ± 8.73ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»8.75 ± 0.96ï¼½ vs ï¼»21.75 ± 1.71ï¼½ pg/ml, P<0.05) and SOD (ï¼»140.82 ± 10.08ï¼½ vs ï¼»358.52 ± 40.41ï¼½ U/mg prot, P<0.05), but remarkable increases in the sperm deformity rate (ï¼»37.33 ± 2.08ï¼½ vs ï¼»15.33±1.53ï¼½%, P<0.05) and MDA level (ï¼»54.89±6.09ï¼½ vs ï¼»30.21±2.17ï¼½ nmol/ng prot, P<0.05). The mice of the JSP treatment group, in comparison with the TI model controls, exhibited markedly increased body weight (ï¼»39.80±2.89ï¼½ vs ï¼»34.63±1.92ï¼½g, P<0.05), testis weight (ï¼»130.00 ± 11.00ï¼½ vs ï¼»80.00 ± 3.90ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.28 ± 0.01ï¼½ vs ï¼»0.22 ± 0.01ï¼½%, P<0.05), sperm motility (ï¼»76.00 ± 5.29ï¼½% vs ï¼»48.66 ± 8.08ï¼½%, P<0.05), sperm concentration (ï¼»56.08 ± 4.29ï¼½ vs ï¼»28.42 ± 5.26ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»15.50 ± 1.29ï¼½ vs ï¼»8.75 ± 0.96ï¼½ pg/ml, P<0.05) and SOD (ï¼»206.59 ± 16.38ï¼½ vs ï¼»140.82 ± 10.08ï¼½ U/mg prot, P<0.05), but decreased sperm deformity rate (ï¼»25.01 ± 2.99ï¼½% vs ï¼»37.33 ± 2.08ï¼½%, P<0.05) and MDA level (ï¼»35.84 ± 3.61ï¼½ vs ï¼»54.89 ± 6.09ï¼½ nmol/ng prot, P<0.05). The mRNA expressions of NOQ-1, Nrf2 and HO-1 in the testis tissue were significantly lower and that of Caspase-3 remarkably higher in the TI model control than in the blank control group (P<0.05), while those of Nrf2 and HO-1 significantly higher and that of Caspase-3 markedly lower in the JSP treatment group than in the TI model controls (P<0.05). Histopathological images displayed reduced layers of spermatogenic cells in the seminiferous tubules, complete exfoliation of the spermatogenic cells in some of the tubules and decreased number of sperm cells in the TI model controls, which were all found normal in the JSP treatment group. CONCLUSIONS: Jinkui Shenqi Pills can effectively inhibit cyclophosphamide-induced testis injury, which may be related to its effect of regulating the gene expression of the Nrf2 signaling pathway and enhancing the activity of antioxidant enzymes.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Motilidade dos Espermatozoides , Testículo/metabolismo , Animais , Ciclofosfamida , Expressão Gênica , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais , Contagem de Espermatozoides , Espermatozoides , Testículo/efeitos dos fármacos
8.
J Int Med Res ; 48(6): 300060520931242, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32588696

RESUMO

OBJECTIVE: The role and mechanism of tetrathiomolybdate (TM) in cancer-associated fibroblasts (CAFs) in colon cancer using three-dimensional (3D) culture were investigated, and the associations between the focal adhesion kinase (FAK) pathway and epithelial-mesenchymal transition (EMT) in CAFs were explored. METHODS: A 3D co-culture model of colon cancer LOVO cells with CAFs and normal fibroblasts (NFs) was established using Matrigel as a scaffold material. The differential expression of LOXL2 (lysyl oxidase-like 2) in the supernatant of CAFs and NFs was determined using ELISA, and expression levels of EMT-related proteins and FAK signaling pathway-related proteins were determined using western blot. RESULTS: LOXL2 levels secreted by CAFs were higher compared with that secreted by NFs. In the CAF + LOVO group, compared with the LOVO group, E-cadherin expression decreased significantly, while N-cadherin and F-PAK expression increased significantly. TM results were opposite compared with the above results. CONCLUSIONS: CAFs stimulate EMT in human colon cancer LOVO cells by secreting LOXL2 to activate the FAK signaling pathway, thereby promoting tumor metastasis. TM inhibited the occurrence of EMT in the CAF-induced colon cancer LOVO cell line, thereby reducing the invasion and metastasis of colon cancer cells.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias do Colo , Linhagem Celular Tumoral , Movimento Celular , Transição Epitelial-Mesenquimal , Fibroblastos , Proteína-Tirosina Quinases de Adesão Focal , Humanos
9.
J Mater Chem B ; 4(32): 5464-5474, 2016 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32263470

RESUMO

Phagocytic clearance and inefficient targeting are two major concerns for nanomedicines in cancer therapy. In this study, cell membrane inspired multifunctional copolymers (PMNCFs) were synthesized by a combination of cell membrane stealthy hydrophilic phosphorylcholine (PC), hydrophobic cholesterol (Chol) and tumor targeting folic acid (FA) functionalities on the different side chain ends. PMNCF micelles were prepared in aqueous solution to form a cell membrane mimetic structure with linked folic acid ligands as the protruding antennae on the surface of the micelles. Coumarin-6 loaded PMNCF micelles indicated that the mouse peritoneal macrophage cell uptake efficiency was suppressed to 1/10 compared with that of PLA nanoparticles. Doxorubicin loaded micelle measurements demonstrated that up to 30% of the drug could be obtained forming a stable formulation under both storage and physiological conditions. Tumor cell uptake and toxicity studies revealed that FA-decorated PMNCF micelles could increase MADB-106 cell uptake by 4-fold, and DOX loaded PMNCF micelles could kill tumor cells more efficiently than the same amount of free DOX. These exciting results confirmed the great potential of the stable, stealthy and tumor cell targeting PMNCF micelles for developing advanced long circulation and target-selective drug delivery nanoparticles.

10.
J Biomater Sci Polym Ed ; 25(14-15): 1703-16, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25183528

RESUMO

Poly(lactic acid) (PLA) nanoparticles (NPs) are the most promising polymer NPs for drug delivery and targeting. However, they are easily recognized as a foreign body and rapidly cleared from the body by the mononuclear phagocyte system. Cell membrane mimetic random copolymers, bearing both zwitterionic phosphorylcholine groups and hydrophobic butyl side chains (PMB) and additional cross-linkable trimethoxysilylpropyl side chains (PMBT), were synthesized and coated on PLA NPs. Effects of the zwitterionic copolymer coatings on the NP size distribution, dispersion stability, and drug release behavior were investigated. Furthermore, the effect of the coatings on phagocytosis was also investigated. Compared with conventional polyvinyl alcohol coating, the cell membrane mimetic copolymer coatings decreased the size and increased the stability of the PLA NPs aqueous dispersions. More importantly, doxorubicin (DOX) release was well controlled and NPs phagocytosis by mouse peritoneal macrophage was decreased to one-third when the nanoparticles were coated with PMBT. This simple and effective zwitterionic polymer coating strategy may serve as a new route to design and optimize long-circulating intravenously injectable nanoparticle drug carriers.


Assuntos
Materiais Revestidos Biocompatíveis/química , Portadores de Fármacos/química , Ácido Láctico/química , Nanopartículas/química , Fosfolipídeos/química , Polímeros/química , Animais , Transporte Biológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/metabolismo , Materiais Revestidos Biocompatíveis/toxicidade , Doxorrubicina/química , Portadores de Fármacos/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ácido Láctico/metabolismo , Ácido Láctico/toxicidade , Camundongos , Fagócitos/metabolismo , Poliésteres , Polímeros/metabolismo , Polímeros/toxicidade
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 394-7, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22512176

RESUMO

Applying Raman spectrometry to detect several kinds of oils such as petrol, diesel oil, naphtha and KHF (aviation fuel hydro treating), the authors can explore the regular laws existing among these oils. The authors detected 150 cases of oils using Raman spectrometer developed by ourselves with 785 nm excitation wavelength miniature portable, and dealed with these spectra-paragraphs of the oils on level and SNV (normalization method) methods. The spectrograms of four categories of oils including petrol, diesel oil, naphtha and KHF and also the additives of them have different characteristics and rules. According to the alkenes peak's location and intensity we can distinguish petrol and naphtha, and then screen out some unqualified petrol. Raman spectrometry is very simple and has advantages that it needs a small amount of oil samples, at the same time, it also has no damage to test samples. The spectra-paragraphs show that different kinds of samples have different character on location and intensity of Raman peak. The Raman spectrometry method has great potential on establishing a rapid oil screening detection and identification method.


Assuntos
Óleos , Análise Espectral Raman , Gasolina , Petróleo
12.
Zhonghua Yi Xue Za Zhi ; 89(10): 655-8, 2009 Mar 17.
Artigo em Chinês | MEDLINE | ID: mdl-19595056

RESUMO

OBJECTIVE: To investigate the characteristics of glycemic stability in the first-degree relatives of type 2 diabetes mellitus (T2DM) patients by continuous glucose monitoring system (CGMS). METHODS: Twenty-two first-degree relatives (FDRs) of T2DM patients and 28 age and gender-matched controls underwent CGMS to obtain the mean blood glucose (MBG), standard deviation of MBG (SDBG), mean of daily differences (MODD), and mean amplitude of glycemic excursions (MAGE). Oral glucose tolerance test (OGTT) was conducted. Blood glucose, serum lipids, and serum insulin were assayed. The insulin sensitivity and resistance was assessed by HOMA-beta, HOMA-IR, DeltaI(30)/DeltaG(30) and modified beta cell function index (MBCI). RESULTS: There were no significant differences between the FDR and control groups in the levels of plasma glucose in OGTT, MBG, SDBG, and MOOD. However, the MAGE level of the FDR group was (2.3 +/- 0.5) mmol/L, significantly higher than that of the control group [(2.0 +/- 0.6) mmol/L, P < 0.05]. The MBCI level of the FDR group was 17.6 (16.9 - 50.0), significantly lower than that of the control group [36.0 (15.7 - 59.6), P < 0.05]. There were no significant differences in the serum lipids profile, body fat distribution, HOMA-beta, HOMA-IR, and DeltaI(30)/DeltaG(30) between these two groups. CONCLUSION: The excursion of blood glucose is greater in the FDRs of T2DM patients. CGMS is more sensitive to discover such change than OGTT.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Automonitorização da Glicemia , Estudos de Casos e Controles , Família , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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