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1.
New Phytol ; 242(2): 687-699, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38396376

RESUMO

The effect of pathogens on host diversity has attracted much attention in recent years, yet how the influence of pathogens on individual plants scales up to affect community-level host diversity remains unclear. Here, we assessed the effects of foliar fungal pathogens on plant growth and species richness using allometric growth theory in population-level and community-level foliar fungal pathogen exclusion experiments. We calculated growth scaling exponents of 24 species to reveal the intraspecific size-dependent effects of foliar fungal pathogens on plant growth. We also calculated the intercepts to infer the growth rates of relatively larger conspecific individuals. We found that foliar fungal pathogens inhibited the growth of small conspecific individuals more than large individuals, resulting in a positive allometric growth. After foliar fungal pathogen exclusion, species-specific growth scaling exponents and intercepts decreased, but became positively related to species' relative abundance, providing a growth advantage for individuals of abundant species with a higher growth scaling exponent and intercept compared with rare species, and thus reduced species diversity. By adopting allometric growth theory, we elucidate the size-dependent mechanisms through which pathogens regulate species diversity and provide a powerful framework to incorporate antagonistic size-dependent processes in understanding species coexistence.


Assuntos
Fungos , Plantas , Plantas/microbiologia , Fungos/patogenicidade
2.
Arterioscler Thromb Vasc Biol ; 43(6): 910-926, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078289

RESUMO

BACKGROUND: The benefits of exercise on the cardiovascular system are widely recognized; however, the underlying mechanisms are unknown. Here, we report the effect of the long noncoding RNA NEAT1 (nuclear paraspeckle assembly transcript 1), which is regulated by exercise, on atherosclerosis development after N6-methyladenosine (m6A) modifications. METHODS: Using clinical cohorts and NEAT1-/- mice, we determined the exercise-mediated expression and role of NEAT1 in atherosclerosis. To investigate the mechanism of epigenetic modification of NEAT1 regulated by exercise, we identified METTL14 (methyltransferase-like 14)-a key m6A modification enzyme under exercise-and found that METTL14 alters the expression and role of NEAT1 through m6A modification and elucidated the specific mechanism of METTL14 in vitro and in vivo. Finally, the NEAT1 downstream regulatory network was investigated. RESULTS: We found that NEAT1 expression was downregulated with exercise and that downregulation of NEAT1 was an important factor in the improvement of atherosclerosis with exercise. Exercise-mediated loss of function of NEAT1 can delay atherosclerosis. Mechanistically, we showed that exercise induced a significant downregulation of m6A modification and METTL14, which binds to the m6A sites of NEAT1 and promotes NEAT1 expression through subsequent YTHDC1 (YTH domain-containing 1) recognition to promote endothelial pyroptosis. Furthermore, NEAT1 induces endothelial pyroptosis by binding KLF4 (Kruppel-like factor 4) to promote the transcriptional activation of the key pyroptotic protein NLRP3 (NOD-like receptor thermal protein domain-associated protein 3), whereas exercise can attenuate NEAT1-mediated endothelial pyroptosis to improve atherosclerosis. CONCLUSIONS: Our study of NEAT1 provides new insights into the improvement of atherosclerosis by exercise. This finding demonstrates the role of exercise-mediated NEAT1 downregulation in atherosclerosis while expanding our understanding of the mechanisms by which exercise regulates long noncoding RNA function through epigenetic modifications.


Assuntos
Aterosclerose , RNA Longo não Codificante , Animais , Camundongos , Adenosina , Aterosclerose/genética , Aterosclerose/prevenção & controle , Piroptose , RNA Longo não Codificante/genética
3.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33495330

RESUMO

Multiplex assays, involving the simultaneous use of multiple circulating tumor DNA (ctDNA) markers, can improve the performance of liquid biopsies so that they are highly predictive of cancer recurrence. We have developed a single-tube methylation-specific quantitative PCR assay (mqMSP) that uses 10 different methylation markers and is capable of quantitative analysis of plasma samples with as little as 0.05% tumor DNA. In a cohort of 179 plasma samples from colorectal cancer (CRC) patients, adenoma patients, and healthy controls, the sensitivity and specificity of the mqMSP assay were 84.9% and 83.3%, respectively. In a head-to-head comparative study, the mqMSP assay also performed better for detecting early-stage (stage I and II) and premalignant polyps than a published SEPT9 assay. In an independent longitudinal cohort of 182 plasma samples (preoperative, postoperative, and follow-up) from 82 CRC patients, the mqMSP assay detected ctDNA in 73 (89.0%) of the preoperative plasma samples. Postoperative detection of ctDNA (within 2 wk of surgery) identified 11 of the 20 recurrence patients and was associated with poorer recurrence-free survival (hazard ratio, 4.20; P = 0.0005). With subsequent longitudinal monitoring, 14 patients (70%) had detectable ctDNA before recurrence, with a median lead time of 8.0 mo earlier than seen with radiologic imaging. The mqMSP assay is cost-effective and easily implementable for routine clinical monitoring of CRC recurrence, which can lead to better patient management after surgery.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , Neoplasias do Colo/cirurgia , Metilação de DNA/genética , Biópsia Líquida , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Antígeno Carcinoembrionário/metabolismo , DNA Tumoral Circulante/sangue , Estudos de Coortes , Neoplasias do Colo/sangue , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mutação/genética , Cuidados Pós-Operatórios , Reprodutibilidade dos Testes , Septinas/genética
4.
Sens Actuators B Chem ; 348: 130706, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34493903

RESUMO

The lateral flow immunoassay (LFIA) has played a crucial role in early diagnosis during the current COVID-19 pandemic owing to its simplicity, speed and affordability for coronavirus antibody detection. However, the sensitivity of the commercially available LFIAs needs to be improved to better prevent the spread of the infection. Here, we developed an ultra-sensitive surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-based LFIA) strip for simultaneous detection of anti-SARS-CoV-2 IgM and IgG by using gap-enhanced Raman nanotags (GERTs). The GERTs with a 1 nm gap between the core and shell were used to produce the "hot spots", which provided about 30-fold enhancement as compared to conventional nanotags. The COVID-19 recombinant antigens were conjugated on GERTs surfaces and replaced the traditional colloidal gold for the Raman sensitive detection of human IgM and IgG. The LODs of IgM and IgG were found to be 1 ng/mL and 0.1 ng/mL (about 100 times decrease was observed as compared to commercially available LFIA strips), respectively. Moreover, under the condition of common nano-surface antigen, precise SERS signals proved the unreliability of quantitation because of the interference effect of IgM on IgG.

5.
BMC Cancer ; 20(1): 1209, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33297998

RESUMO

BACKGROUND: There were scarcely germline variants of familial lung cancer (LC) identified. We conducted an study with whole-exome sequencing of pedigrees with familial lung cancer to analyze the potential genetic susceptibility. METHODS: Probands with the highest hereditary background were identified by our large-scale epidemiological study and five ones were enrolled as a learning set. The germline SNPs (single-nucleotide polymorphisms) of other five similar probands, four healthy individuals in the formerly pedigrees and three patients with sporadic LC were used as a validation set, controlled by three healthy individuals without family history of any cancer. The network of mutated genes was generated using STRING-DB and visualized using Cytoscape. RESULTS: Specific and shared somatic mutations and germline SNPs were not the shared cause of familial lung cancer. However, individual germline SNPs showed distinct protein-protein interaction network patterns in probands versus healthy individuals and patients with sporadic lung cancer. SNP-containing genes were enriched in the PI3K/AKT pathway. These results were validated in the validation set. Furthermore, patients with familial lung cancer were distinguished by many germline variations in the PI3K/AKT pathway by a simple SVM classification method. It is worth emphasizing that one person with many germline variations in the PI3K/AKT pathway developed lung cancer during follow-up. CONCLUSIONS: The phenomenon that the enrichments of germline SNPs in the PI3K/AKT pathway might be a major predictor of familial susceptibility to lung cancer.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Pequenas/genética , Carcinoma de Células Escamosas/genética , Mutação em Linhagem Germinativa , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/genética , Síndromes Neoplásicas Hereditárias/genética , Fosfatidilinositol 3-Quinases/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genética , Estudos de Casos e Controles , Transformação Celular Neoplásica/genética , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Humanos , Incidência , Masculino , Proteínas de Neoplasias/fisiologia , Linhagem , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Máquina de Vetores de Suporte , Sequenciamento do Exoma
6.
Clin Chem Lab Med ; 59(1): 91-99, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32673280

RESUMO

Objectives: Colorectal cancer (CRC) screening using stool samples is now in routine use where tumor DNA methylation analysis for leading markers such as NDRG4 and SDC2 is an integral part of the test. However, processing stool samples for reproducible and efficient extraction of human genomic DNA remains a bottleneck for further research into better biomarkers and assays. Methods: We systematically evaluated several factors involved in the processing of stool samples and extraction of DNA. These factors include: stool processing (solid and homogenized samples), preparation of DNA from supernatant and pellets, and DNA extraction with column and magnetic beads-based methods. Furthermore, SDC2 and NDRG4 methylation levels were used to evaluate the clinical performance of the optimal protocol. Results: The yield of total and human genomic DNA (hgDNA) was not reproducible when solid stool scraping is used, possibly due to sampling variations. More reproducible results were obtained from homogenized stool samples. Magnetic beads-based DNA extraction using the supernatant from the homogenized stool was chosen for further analysis due to better reproducibility, higher hgDNA yield, lower non-hgDNA background, and the potential for automation. With this protocol, a combination of SDC2 and NDRG4 methylation signals with a linear regression model achieved a sensitivity and specificity of 81.82 and 93.75%, respectively. Conclusions: Through the systematic evaluation of different stool processing and DNA extraction methods, we established a reproducible protocol for analyzing tumor DNA methylation markers in stool samples for colorectal cancer screening.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/diagnóstico , DNA/análise , Testes Diagnósticos de Rotina/métodos , Detecção Precoce de Câncer/métodos , Fezes/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/química , DNA/química , Metilação de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Musculares/genética , Proteínas do Tecido Nervoso/genética , Reprodutibilidade dos Testes , Manejo de Espécimes/métodos , Sindecana-2/genética
7.
Exp Cell Res ; 375(1): 1-10, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30412716

RESUMO

Long non-coding RNA HOXA-AS2 (HOXA cluster antisense RNA 2) has been reported to function as an oncogene in different types of cancers including breast cancer, liver cancer, gastric cancer and colorectal cancer, etc. However, its role in the development and progression of bladder cancer remains unknown. This study aimed to examine the expression of HOXA-AS2 in bladder cancer, to explore its role in the migration, invasion and stemness of bladder cancer cells and to further identify the potential downstream target miRNAs of HOXA-AS2 in this type of cancer. Our results firstly demonstrated the upregulation of HOXA-AS2 in both bladder cancer cells and clinical bladder tumors. Such upregulation was also positively correlated with the advanced stage, invasion and lymph node metastasis of bladder cancer as well as the expression of cancer stem cell marker OCT4 in patients. After knockdown of HOXA-AS2 in bladder cancer 5637 and T24 cells, the migration, invasion and stemness of cancer cells were significantly inhibited, indicating the capability of HOXA-AS2 to promote the migration, invasion and stemness of bladder cancer cells. Knockdown of HOXA-AS2 also suppressed in vivo tumor growth in the nude mice. Furthermore, this study also identified miR-125b as a downstream target of HOXA-AS2 and revealed the downregulation of miR-125b by HOXA-AS2 as well as the involvement of HOXA-AS2/miR-125b/Smad2 interactions in the functional role of HOXA-AS2 in mediating the migration, invasion and stemness of bladder cancer cells. Together, our findings suggest that HOXA-AS2 might be a potential biomarker and target for the diagnosis, monitoring and treatment of bladder cancer.


Assuntos
MicroRNAs/genética , RNA Longo não Codificante/genética , Proteína Smad2/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Masculino , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fator 3 de Transcrição de Octâmero/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/genética , Neoplasias da Bexiga Urinária/patologia
8.
Eur Spine J ; 29(5): 1147-1158, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32200495

RESUMO

PURPOSE: To evaluate the safety and efficacy of a system aiming to correct scoliosis called "electromagnetically controlled shape-memory alloy rods" (EC-SMAR) used in a rabbit model. METHODS: We heat-treated shape-memory alloy (SMA) rods to achieve a transition temperature between 34 and 47 °C and a C-shape austenite phase. We then developed a water-cooled generator capable of generating an alternating magnetic field (100 kHz) for induction heating. We next studied the efficacy of this system in vitro and determined some parameters prior to proceeding with animal experiments. We then employed a rabbit model, in which we fixed a straight rod along the spinous processes intraoperatively, and conducted induction heating postoperatively every 4 days for 1 month, while performing periodic X-ray assessments. RESULTS: Significant kyphotic deformations with Cobb angles of about 45° (p < 0.01) were created in five rabbits, and no complications occurred throughout the experiment. The rabbits are still very much alive and do not show any signs of discomfort. CONCLUSIONS: This is the first system that can modulate spinal deformation in a gradual, contactless, noninvasive manner through electromagnetic induction heating applied to SMA alloy rods. Although this study dealt with healthy spines, it provides promising evidence that this device also has the capacity to correct human kyphosis and even scoliosis in the future. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Escoliose , Ligas de Memória da Forma , Ligas , Animais , Níquel , Coelhos , Escoliose/cirurgia , Coluna Vertebral , Titânio
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 956-966, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33369334

RESUMO

The dynamic coupling of stent degradation and vessel remodeling can influence not only the structural morphology and material property of stent and vessel, but also the development of in-stent restenosis. The research achievements of biomechanical modelling and analysis of stent degradation and vessel remodeling were reviewed; several noteworthy research perspectives were addressed, a stent-vessel coupling model was developed based on stent damage function and vessel growth function, and then concepts of matching ratio and risk factor were established so as to evaluate the treatment effect of stent intervention, which may lay the scientific foundation for the structure design, mechanical analysis and clinical application of biodegradable stent.


Assuntos
Stents , Fenômenos Biomecânicos , Constrição Patológica , Humanos
10.
Cancer Cell Int ; 19: 42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30858759

RESUMO

BACKGROUND: Human bladder cancer is one of the common malignant tumors, and it mainly occurs in men. miR-182-5p, a member of miR-183 family, acts as tumor suppressor or oncogene in various kinds of tumors. In this study, we first investigate that the absence of miR-182-5p in human bladder cancer promotes tumor growth by regulating the expression of Cofilin 1, an actin modulating-protein. METHODS: Human bladder tumor tissue specimens were collected to detect the expression of miR-182-5p and Cofilin 1 by qRT-PCR. Luciferase activity assay was performed to demonstrate the regulation of Cofilin 1 mRNA 3'UTR by miR-182-5p. Then, cell experiments were performed to analysis the effect of miR-182-5p/Cofilin 1 pathway on tumor cell proliferation, migration, invasion and colony forming efficiency. Finally, xenograft tumor models were established to evaluate the role of miR-182-5p in tumorigenesis abilities in vivo. RESULTS: qRT-PCR and Western blotting analysis showed that Cofilin 1 expression was up-regulated in both bladder cancer tissues and cell lines compared with normal. Luciferase activity assay showed that miR-182-5p specifically targets Cofilin 1 mRNA 3'UTR and represses the expression of Cofilin 1. Also, miR-182-5p inhibited bladder tumor cell proliferation, migration, invasion and colony forming efficiency. Furthermore, xenograft tumor model assay showed that miR-182-5p plays a negative role in bladder cancer tumorigenesis abilities in vivo. CONCLUSION: Present results suggest that miR-182-5p could inhibit human bladder tumor growth by repressing Cofilin 1 expression. Our findings may provide a new horizon for exploring therapeutic target of bladder cancer.

11.
J Eukaryot Microbiol ; 64(2): 278-281, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27397809

RESUMO

The microsporidia Nosema bombycis is the insect pathogen of pebrine disease severely destructive to sericulture production. Here, we describe the use of Escherichia coli HT115 strain (DE3) to express double-strand RNAs targeting the gene encoding ADP/ATP protein in N. bombycis. The results showed that dsRNAs deferentially suppressed the gene expression during N. bombycis infection in the silkworm, and the effect waned gradually. Our results, for the first time, provide a tool to utilize the dsRNA expressed by recombinant E. coli to control the pebrine disease of the domestic silkworm.


Assuntos
Escherichia coli/genética , Regulação da Expressão Gênica , Nosema/genética , Doenças dos Animais/microbiologia , Doenças dos Animais/prevenção & controle , Animais , Bombyx/microbiologia , Proteínas de Transporte/genética , DNA Fúngico/genética , Regulação para Baixo , Proteínas Fúngicas/genética , Microsporidiose/microbiologia , Microsporidiose/prevenção & controle , Microsporidiose/veterinária , Nosema/patogenicidade , Interferência de RNA , RNA de Cadeia Dupla/genética , Proteínas Recombinantes , Esporos
12.
Phys Chem Chem Phys ; 18(48): 32762-32771, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27878170

RESUMO

Absolute cross sections (CSs) for the interaction of low energy electrons with condensed macromolecules are essential parameters to accurately model ionizing radiation induced reactions. To determine CSs for various conformational DNA damage induced by 2-20 eV electrons, we investigated the influence of the attenuation length (AL) and penetration factor (f) using a mathematical model. Solid films of supercoiled plasmid DNA with thicknesses of 10, 15 and 20 nm were irradiated with 4.6, 5.6, 9.6 and 14.6 eV electrons. DNA conformational changes were quantified by gel electrophoresis, and the respective yields were extrapolated from exposure-response curves. The absolute CS, AL and f values were generated by applying the model developed by Rezaee et al. The values of AL were found to lie between 11 and 16 nm with the maximum at 14.6 eV. The absolute CSs for the loss of the supercoiled (LS) configuration and production of crosslinks (CL), single strand breaks (SSB) and double strand breaks (DSB) induced by 4.6, 5.6, 9.6 and 14.6 eV electrons are obtained. The CSs for SSB are smaller, but similar to those for LS, indicating that SSB are the main conformational damage. The CSs for DSB and CL are about one order of magnitude smaller than those of LS and SSB. The value of f is found to be independent of electron energy, which allows extending the absolute CSs for these types of damage within the range 2-20 eV, from previous measurements of effective CSs. When comparison is possible, the absolute CSs are found to be in good agreement with those obtained from previous similar studies with double-stranded DNA. The high values of the absolute CSs of 4.6 and 9.6 eV provide quantitative evidence for the high efficiency of low energy electrons to induce DNA damage via the formation of transient anions.


Assuntos
Dano ao DNA , Elétrons , Modelos Moleculares , Animais , DNA , Humanos , Conformação de Ácido Nucleico
13.
Chin J Cancer ; 33(7): 346-50, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24823994

RESUMO

As molecular targets continue to be identified and more targeted inhibitors are developed for personalized treatment of non-small cell lung cancer (NSCLC), multigene mutation determination will be needed for routine oncology practice and for clinical trials. In this study, we evaluated the sensitivity and specificity of multigene mutation testing by using the Snapshot assay in NSCLC. We retrospectively reviewed a cohort of 110 consecutive NSCLC specimens for which epidermal growth factor receptor (EGFR) mutation testing was performed between November 2011 and December 2011 using Sanger sequencing. Using the Snapshot assay, mutation statuses were detected for EGFR, Kirsten rate sarcoma viral oncogene homolog (KRAS), phosphoinositide-3-kinase catalytic alpha polypeptide (PIK3CA), v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), v-ras neuroblastoma viral oncogene homolog (NRAS), dual specificity mitogen activated protein kinase kinase 1 (MEK1), phosphatase and tensin homolog (PTEN), and human epidermal growth factor receptor 2 (HER2) in patient specimens and cell line DNA. Snapshot data were compared to Sanger sequencing data. Of the 110 samples, 51 (46.4%) harbored at least one mutation. The mutation frequency in adenocarcinoma specimens was 55.6%, and the frequencies of EGFR, KRAS, PIK3CA, PTEN, and MEK1 mutations were 35.5%, 9.1%, 3.6%, 0.9%, and 0.9%, respectively. No mutation was found in the HER2, NRAS, or BRAF genes. Three of the 51 mutant samples harbored double mutations: two PIK3CA mutations coexisted with KRAS or EGFR mutations, and another KRAS mutation coexisted with a PTEN mutation. Among the 110 samples, 47 were surgical specimens, 60 were biopsy specimens, and 3 were cytological specimens; the corresponding mutation frequencies were 51.1%, 41.7%, and 66.7%, respectively (P = 0.532). Compared to Sanger sequencing, Snapshot specificity was 98.4% and sensitivity was 100% (positive predictive value, 97.9%; negative predictive value, 100%). The Snapshot assay is a sensitive and easily customized assay for multigene mutation testing in clinical practice.


Assuntos
Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Mutação , Classe I de Fosfatidilinositol 3-Quinases , Genes erbB-1 , Genes erbB-2 , Genes ras , Humanos , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas , Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas p21(ras) , Estudos Retrospectivos , Proteínas ras
14.
Biomater Adv ; 156: 213693, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992478

RESUMO

Biodegradable stents can support vessels for an extended period, maintain vascular patency, and progressively degrade once vascular remodeling is completed, thereby reducing the constraints of traditional metal stents. An ideal degradable stent must have good mechanical properties, degradation behavior, and biocompatibility. Zinc has become a new type of biodegradable metal after magnesium and iron, owing to its suitable degradation rate and good biocompatibility. However, zinc's poor strength and ductility make it unsuitable as a vascular stent material. Therefore, this paper reviewed the primary methods for improving the overall properties of zinc. By discussing the mechanical properties, degradation behavior, and biocompatibility of various improvement strategies, we found that alloying is the most common, simple, and effective method to improve mechanical properties. Deformation processing can further improve the mechanical properties by changing the microstructures of zinc alloys. Surface modification is an important means to improve the biological activity, blood compatibility and corrosion resistance of zinc alloys. Meanwhile, structural design can not only improve the mechanical properties of the vascular stents, but also endow the stents with special properties such as negative Poisson 's ratio. Manufacturing zinc alloys with excellent degradation properties, improved mechanical properties and strong biocompatibility and exploring their mechanism of interaction with the human body remain areas for future research.


Assuntos
Materiais Biocompatíveis , Zinco , Humanos , Materiais Biocompatíveis/uso terapêutico , Implantes Absorvíveis , Ligas , Stents , Magnésio/farmacologia , Magnésio/uso terapêutico
15.
Oncol Lett ; 28(1): 295, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38737975

RESUMO

Apolipoprotein A-I (APOA1) performs different roles in different subtypes of breast cancer. It is hypothesized to function as a tumor suppressor in basal-like breast cancer (BLBC). However, the specific role of APOA1 in BLBC and its underlying mechanisms remain unknown. The findings of the present study demonstrated a positive correlation between the expression level of APOA1 and the overall survival of patients with BLBC. Ectopic expression of APOA1 effectively inhibits the proliferation and metastasis of BLBC cells in vitro, and these effects are closely related to DNA methylation. To the best of our knowledge, the present study is the first to report increased methylation of the promoter region and decreased methylation of the structural genes of APOA1 in BLBC cells. These alterations resulted in the downregulation of APOA1 expression and suppression of BLBC tumor growth. Collectively, the results of the present study suggested that APOA1 mRNA expression is negatively regulated by DNA methylation in BLBC. Therefore, low expression of APOA1 may be a potential risk biomarker to predict survival in patients with BLBC.

16.
Immun Inflamm Dis ; 12(1): e1150, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270308

RESUMO

BACKGROUND: Recently, many studies have been conducted to examine immune response modification at epigenetic level, but the candidate effect of RNA 5-methylcytosine (m5 C) modification on tumor microenvironment (TME) of acute myeloid leukemia (AML) is still unknown at present. METHODS: We assessed the patterns of m5 C modification among 417 AML cases by using nine m5 C regulators. Thereafter, we associated those identified modification patterns with TME cell infiltration features. Additionally, stepwise regression and LASSO Cox regression analyses were conducted for quantifying patterns of m5 C modification among AML cases to establish the m5 C-score. Meanwhile, we validated the expression of genes in the m5C-score model by qRT-PCR. Finally, the present work analyzed the association between m5 C-score and AML clinical characteristics and prognostic outcomes. RESULTS: In total, three different patterns of m5 C modification (m5 C-clusters) were identified, and highly differentiated TME cell infiltration features were also identified. On this basis, evaluating patterns of m5 C modification in single cancer samples was important for evaluating the immune/stromal activities in TME and for predicting prognosis. In addition, the m5 C-score was established, which showed a close relation with the overall survival (OS) of test and training set samples. Moreover, multivariate Cox analysis suggested that our constructed m5 C-score served as the independent predicting factor for the prognosis of AML (hazard ratio = 1.57, 95% confidence interval = 1.38-1.79, p < 1e-5 ). CONCLUSIONS: This study shows that m5 C modification may be one of the key roles in the formation of diversity and complexity of TME. Meanwhile, assessing the patterns of m5 C modification among individual cancer samples is of great importance, which provides insights into cell infiltration features within TME, thereby helping to develop relevant immunotherapy and predict patient prognostic outcomes.


Assuntos
Leucemia Mieloide Aguda , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Leucemia Mieloide Aguda/genética , RNA , Diferenciação Celular , Metilação
17.
Gene ; 901: 148168, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38244949

RESUMO

BACKGROUND: Recurrent pregnancy loss (RPL) is associated with variable causes. Its etiology remains unexplained in about half of the cases, with no effective treatment available. Individuals with RPL have an irregular iron metabolism. In the present study, we identified key genes impacting iron metabolism that could be used for diagnosing and treating RPL. METHODS: We obtained gene expression profiles from the Gene Expression Omnibus (GEO) database. The Molecular Signatures Database was used to identify 14 gene sets related to iron metabolism, comprising 520 iron metabolism genes. Differential analysis and a weighted gene co-expression network analysis (WGCNA) of gene expression revealed two iron metabolism-related hub genes. Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry were used on clinical samples to confirm our results. The receiver operating characteristic (ROC) analysis and immune infiltration analysis were conducted. In addition, we analyzed the distribution of genes and performed CellChat analysis by single-cell RNA sequencing. RESULTS: The expression of two hub genes, namely, CDGSH iron sulfur domain 2 (CISD2)and Cytochrome P450 family 17 subfamily A member 1 (CYP17A1), were reduced in RPL, as verified by both qPCR and immunohistochemistry. The Gene Ontology (GO) analysis revealed the genes predominantly engaged in autophagy and iron metabolism. The area under the curve (AUC) demonstrated better diagnostic performance for RPL using CISD2 and CYP17A1. The single-cell transcriptomic analysis of RPL demonstrated that CISD2 is expressed in the majority of cell subpopulations, whereas CYP17A1 is not. The cell cycle analysis revealed highly active natural killer (NK) cells that displayed the highest communications with other cells, including the strongest interaction with macrophages through the migratory inhibitory factor (MIF) pathway. CONCLUSIONS: Our study suggested that CISD2 and CYP17A1 genes are involved in abnormal iron metabolism, thereby contributing to RPL. These genes could be used as potential diagnostic and therapeutic markers for RPL.


Assuntos
Ferro , RNA , Feminino , Gravidez , Humanos , Sequência de Bases , Análise de Sequência de RNA , Área Sob a Curva , Esteroide 17-alfa-Hidroxilase
18.
Mol Cancer ; 12: 61, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23758992

RESUMO

BACKGROUND: Aberrant activation of the proto-oncogene B-cell lymphoma/leukemia 11A (BCL11A) has been implicated in the pathogenesis of leukemia and lymphoma. However, the clinical significance of BCL11A in non-small cell lung cancer (NSCLC) remains unknown. RESULTS: We examined BCL11A expression at the protein and mRNA levels in a cohort (n=114) of NSCLC patients and assessed the relationship between BCL11A expression and clinicopathological parameters. Data from array-based Comparative Genomic Hybridization (aCGH) and microRNA transfection experiments were integrated to explore the potential mechanisms of abnormal BCL11A activation in NSCLC. Compared to adjacent non-cancerous lung tissues, BCL11A expression levels were specifically upregulated in NSCLC tissues at both the mRNA (t=9.81, P<0.001) and protein levels. BCL11A protein levels were higher in patients with squamous histology (χ2=15.81, P=0.001), smokers (χ2=8.92, P=0.004), patients with no lymph node involvement (χ2=5.14, P=0.029), and patients with early stage disease (χ2=3.91, P=0.048). A multivariate analysis demonstrated that in early stage NSCLC (IA-IIB), BCL11A was not only an independent prognostic factor for disease-free survival (hazards ratio [HR] 0.24, 95% confidence interval [CI] 0.12-0.50, P<0.001), but also for overall survival (HR=0.23, 95% CI 0.09-0.61, P=0.003). The average BCL11A expression level was much higher in SCC samples with amplifications than in those without amplifications (t=3.30, P=0.023). Assessing functionality via an in vitro luciferase reporter system and western blotting, we found that the BCL11A protein was a target of miR-30a. CONCLUSIONS: Our results demonstrated that proto-oncogene BCL11A activation induced by miR-30a and gene amplification may be a potential diagnostic and prognostic biomarker for effective management of this disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Proteínas de Transporte/genética , Amplificação de Genes , Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , MicroRNAs/genética , Proteínas Nucleares/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte/metabolismo , Linhagem Celular , Variações do Número de Cópias de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Nucleares/metabolismo , Prognóstico , Proto-Oncogene Mas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recidiva , Proteínas Repressoras
19.
Cardiovasc Intervent Radiol ; 46(1): 112-119, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36053343

RESUMO

PURPOSE: To explore the temperature threshold of thermal damage to growth plates. METHODS: Nine rabbits were divided into three groups for femoral ablation, exposing the growth plate to different temperatures (T1 = 43-45 °C; T2 = 46-48 °C; T3 = 49-51 °C). After 5 weeks, the changes in the femurs were assessed by macroscopic images, micro-CT, haematoxylin and eosin staining, and immunohistochemistry of Col2a1 (type II collagen). At the cellular level, rabbit epiphyseal chondrocytes were exposed to 37 °C, 44 °C, 47 °C and 50 °C for 5 min. Then, proliferation and chondrogenic differentiation were detected. RESULTS: The rabbits in the T2 and T3 groups developed length discrepancies and axial deviations of femurs, abnormal newly formed bone in the marrow cavity, disorganized growth plates and decreased Col2a1 expression. At the cellular level, the cells exposed to 47 °C and 50 °C for 5 min showed decreased viability, increased apoptosis, decreased extracellular matrix synthesis and decreased matrix mineralization. However, the changes in rabbits in the T1 group and cells at 44 °C did not show a significant difference. CONCLUSION: The ablation of growth plates at temperatures above 45 °C for 5 min results in decreased chondrocyte viability and disorganized growth plates, leading to growth disturbances. Further studies are warranted to confirm these promising initial results.


Assuntos
Lâmina de Crescimento , Ablação por Radiofrequência , Animais , Coelhos , Micro-Ondas , Fêmur/cirurgia , Diferenciação Celular
20.
J Funct Biomater ; 14(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37998116

RESUMO

Current research on the fatigue properties of degradable zinc alloy stents has not yet considered the issue of the fatigue life changing with material properties during the dynamic degradation process. Therefore, in this paper, we established a fatigue damage algorithm to study the fatigue problem affected by the changing of material properties during the dynamic degradation process of the stent under the action of pulsating cyclic loading. Three models: the dynamic degradation model, the dynamic degradation model under pulsating cyclic loading, and the coupled model of fatigue damage and dynamic degradation, were developed to verify the effect of fatigue damage on stent life. The results show that fatigue damage leads to a deeper degree of inhomogeneous degradation of the stent, which affects the service life of the stent. Fatigue damage is a factor that cannot be ignored. Therefore, when studying the mechanical properties and lifetime of degradable stents, incorporating fatigue damage into the study can help more accurately assess the lifetime of the stents.

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