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Cancer is a disease with molecular heterogeneity that is closely related to gene mutations and epigenetic changes. The principal histological subtype of lung cancer is non-small cell lung cancer (NSCLC). Long noncoding RNA (lncRNA) is a kind of RNA that is without protein coding function, playing a critical role in the progression of cancer. In this research, the regulatory mechanisms of lncRNA phosphorylase kinase regulatory subunit alpha 1 antisense RNA 1 (PHKA1-AS1) in the progression of NSCLC were explored. The increased level of N6-methyladenosine (m6A) modification in NSCLC caused the high expression of PHKA1-AS1. Subsequently, high-expressed PHKA1-AS1 significantly facilitated the proliferation and metastasis of NSCLC cells, and these effects could be reversed upon the inhibition of PHKA1-AS1 expression, both in vivo and in vitro. Additionally, the target protein of PHKA1-AS1 was actinin alpha 4 (ACTN4), which is known as an oncogene. Herein, PHKA1-AS1 could enhance the protein stability of ACTN4 by inhibiting its ubiquitination degradation process, thus exerting the function of ACTN4 in promoting the progress of NSCLC. In conclusion, this research provided a theoretical basis for further exploring the potential mechanism of NSCLC metastasis and searching novel biomarkers related to the pathogenesis and progression of NSCLC.
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Non-coding RNAs are crucial for cancer progression, among which miR-34c-3p has been demonstrated to be a tumor suppressor in non-small cell lung cancer (NSCLC). In this study, we attempt to identify flavonoids that can up-regulate miR-34c-3p expression, evaluate the anticancer activity of the flavonoids and explore its underlying mechanism in NSCLC cells. Six flavonoids were screened by RT-qPCR and we found that jaceosidin significantly increased miR-34c-3p expression in A549 cells. We found that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner, indicated by cell counting kit (CCK-8) assay, wound healing assay, transwell assay and EdU assay, we observed that jaceosidin inhibited the proliferation, migration and invasion of A549 and H1975 cells in a dose-relevant manner. Further research suggested that miR-34c-3p bound to the transcriptome of integrin α2ß1 and then inhibited its expression, leading to the inhibitory effect on the migration and invasion of NSCLC. Our study sheds some light on anti-tumor of jaceosidin and provides a potential lead compound for NSCLC therapy.
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BACKGROUND: Microwave ablation (MWA) is an effective treatment option for patients with primary liver cancer. However, it has been reported that the MWA procedure induces a hepatic inflammatory response and injury, which may negatively affect the efficacy of MWA. As such, the discovery of reliable markers to monitor the patient's response to MWA is needed. Golgi protein 73 (GP73) has been shown to be associated with chronic liver disease. To date, the potential value of serum GP73 in the dynamic monitoring during MWA of liver cancer remains unclear. AIM: To examine the effects of MWA on the serum levels of GP73 in patients with primary liver cancer. METHODS: A total of 150 primary liver cancer patients with a single small lesion (≤ 3 cm in diameter) were retrospectively enrolled spanning the period between January 2016 and October 2018. All of the patients received MWA for the treatment of primary liver cancer. Serum GP73, alpha-fetoprotein (AFP), and widely used liver biochemical indicators [serum albumin, total bilirubin (TBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST)] were compared before MWA and at different time points, including 1, 2, and 4 wk following the ablation procedure. RESULTS: Complete tumor ablation was achieved in 95.33% of the patients at 1 mo after MWA. The 1-, 2-, and 3-year disease-free survival rates were 74.67%, 59.33%, and 54.00%, respectively. The serum AFP levels were significantly decreased at 1, 2, and 4 wk after MWA; they returned to the normal range at 12 wk after MWA; and they remained stable thereafter during follow-up in those cases without recurrence. In contrast, the serum GP73 levels were significantly increased at 1 and 2 wk after MWA. The serum GP73 levels reached the peak at 2 wk after MWA, started to decline after hepatoprotective treatment with glycyrrhizin and reduced glutathione, and returned to the pretreatment levels at 12 and 24 wk after MWA. Notably, the changes of serum GP73 in response to MWA were similar to those of TBIL, ALT, and AST. CONCLUSION: Serum GP73 is markedly increased in response to MWA of liver cancer. Thus, serum GP73 holds potential as a marker to monitor MWA-induced inflammatory liver injury in need of amelioration.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Alanina Transaminase , Aspartato Aminotransferases , Bilirrubina , Biomarcadores , Carcinoma Hepatocelular/cirurgia , Glutationa , Ácido Glicirrízico , Humanos , Neoplasias Hepáticas/cirurgia , Proteínas de Membrana , Micro-Ondas/efeitos adversos , Estudos Retrospectivos , Albumina Sérica , alfa-Fetoproteínas/metabolismoRESUMO
BACKGROUND: Acute-on-chronic liver failure (ACLF) is the abrupt exacerbation of declined hepatic function in patients with chronic liver disease. AIM: To explore the independent predictors of short-term prognosis in patients with hepatitis B virus (HBV)-related ACLF and to establish a predictive short-term prognosis model for HBV-related ACLF. METHODS: From January 2016 to December 2019, 207 patients with HBV-related ACLF attending the 910th Hospital of Chinese People's Liberation Army were continuously included in this retrospective study. Patients were stratified based on their survival status 3 mo after diagnosis. Information was collected regarding gender and age; coagulation function in terms of prothrombin time and international normalized ratio (INR); hematological profile in terms of neutrophil-to-lymphocyte ratio (NLR) and platelet count (PLT); blood biochemistry in terms of alanine aminotransferase, aspartate aminotransferase, total bilirubin (Tbil), albumin, cholinesterase, blood urea nitrogen (BUN), creatinine, blood glucose, and sodium (Na); tumor markers including alpha-fetoprotein (AFP) and Golgi protein 73 (GP73); virological indicators including HBV-DNA, HBsAg, HBeAg, Anti-HBe, and Anti-HBc; and complications including hepatic encephalopathy, hepatorenal syndrome, spontaneous peritonitis, gastrointestinal bleeding, and pulmonary infection. RESULTS: There were 157 and 50 patients in the survival and death categories, respectively. Univariate analysis revealed significant differences in age, PLT, Tbil, BUN, NLR, HBsAg, AFP, GP73, INR, stage of liver failure, classification of liver failure, and incidence of complications (pulmonary infection, hepatic encephalopathy, spontaneous bacterial peritonitis, and upper gastrointestinal bleeding) between the two groups (P < 0.05). GP73 [hazard ratio (HR): 1.009, 95% confidence interval (CI): 1.005-1.013, P = 0.000], middle stage of liver failure (HR: 5.056, 95%CI: 1.792-14.269, P = 0.002), late stage of liver failure (HR: 22.335, 95%CI: 8.544-58.388, P = 0.000), pulmonary infection (HR: 2.056, 95%CI: 1.145-3.690, P = 0.016), hepatorenal syndrome (HR: 6.847, 95%CI: 1.930-24.291, P = 0.003), and HBsAg (HR: 0.690, 95%CI: 0.524-0.908, P = 0.008) were independent risk factors for short-term prognosis in patients with HBV-related ACLF. Following binary logistics regression analysis, we arrived at the following formula for predicting short-term prognosis: Logit(P) = Ln(P/1-P) = 0.013 × (GP73 ng/mL) + 1.907 × (middle stage of liver failure) + 4.146 × (late stage of liver failure) + 0.734 × (pulmonary infection) + 22.320 × (hepatorenal syndrome) - 0.529 × (HBsAg) - 5.224. The predictive efficacy of the GP73-ACLF score was significantly better than that of the Model for End-Stage Liver Disease (MELD) and MELD-Na score models (P < 0.05). CONCLUSION: The stage of liver failure, presence of GP73, pulmonary infection, hepatorenal syndrome, and HBsAg are independent predictors of short-term prognosis in patients with HBV-related ACLF, and the GP73-ACLF model has good predictive value among these patients.
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As carriers containing abundant biological information, exosomes could deliver the property of donor cells to recipient cells. Emerging studies have shown that tumor cells could secrete a mass of exosomes into the microenvironment to regulate bystander cells. However, the underlying mechanisms of such a phenomenon remain largely unexplored. In this research, we purified and identified the exosomes of A549 cells and found that A549-cell-derived exosomes promoted BEAS-2B cells migration, invasion, and epithelial-mesenchymal transition (EMT). Importantly, we observed that let-7c-5p and miR-181b-5p were attenuated in A549-cell-derived exosomes compared to BEAS-2B-cell-derived exosomes. The analysis of miRNA expression level in BEAS-2B cells indicated that incubation with A549-cell-derived exosomes reduced the expression levels of let-7c-5p and miR-181b-5p. In transient transfections assay, we found that downregulation of let-7c-5p and miR-181b-5p simultaneously showed stronger promotion of BEAS-2B cells migration and invasion than individually. Moreover, exosomes secreted from A549 cells with upregulated expression of let-7c-5p and miR-181b-5p significantly reduce their regulatory effect on BEAS-2B cells. Bioinformatics analyses revealed that let-7c-5p and miR-181b-5p inhibit the EMT process mainly by regulating focal adhesion and mitogen-activated protein kinase (MAPK) signaling pathway. Thus, our data demonstrated that A549-cell-derived exosomal let-7c-5p and miR-181b-5p could induce migration, invasion, and EMT in BEAS-2B cells, which might be regulated through focal adhesion and MAPK signaling pathway. The expression level of let-7c-5p and miR-181b-5p may show great significance for the early diagnosis of lung cancer.
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Exossomos , MicroRNAs/genética , Células A549 , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Exossomos/genética , Exossomos/metabolismo , Humanos , MicroRNAs/metabolismoRESUMO
With the continuous development of drug screening technology, new screening methodologies and technologies are constantly emerging, driving drug screening into rapid, efficient and high-throughput development. Microfluidics is a rising star in the development of innovative approaches in drug discovery. In this article, we summarize the recent years' progress of microfluidic chip technology in drug screening, including the developmental history, structural design, and applications in different aspects of microfluidic chips on drug screening. Herein, the existing microfluidic chip screening platforms are summarized from four aspects: chip structure design, sample injection and drive system, cell culture technology on a chip, and efficient remote detection technology. Furthermore, this review discusses the application and developmental prospects of using microfluidic chips in drug screening, particularly in screening natural product anticancer drugs based on chemical properties, pharmacological effects, and drug cytotoxicity.
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Técnicas de Cultura de Células , Microfluídica , Avaliação Pré-Clínica de Medicamentos/métodosRESUMO
The inherent heterogeneity of individual cells in cell populations plays significant roles in disease development and progression, which is critical for disease diagnosis and treatment. Substantial evidences show that the majority of traditional gene profiling methods mask the difference of individual cells. Single cell sequencing can provide data to characterize the inherent heterogeneity of individual cells, and reveal complex and rare cell populations. Different microfluidic technologies have emerged for single cell researches and become the frontiers and hot topics over the past decade. In this review article, we introduce the processes of single cell sequencing, and review the principles of microfluidics for single cell analysis. Also, we discuss the common high-throughput single cell sequencing technologies along with their advantages and disadvantages. Lastly, microfluidics applications in single cell sequencing technology for the diagnosis of cancers and immune system diseases are briefly illustrated.
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Sequenciamento de Nucleotídeos em Larga Escala , Técnicas Analíticas Microfluídicas , Análise de Célula Única , Animais , Humanos , CamundongosRESUMO
SARS-CoV-2 infection has become an urgent public health concern worldwide, severely affecting our society and economy due to the long incubation time and high prevalence. People spare no effort on the rapid development of vaccine and treatment all over the world. Amongst the numerous ways of tackling this pandemic, some approaches using extracellular vesicles (EVs) are emerging. In this review, we summarize current prevalence and pathogenesis of COVID-19, involving the combination of SARS-CoV-2 and virus receptor ACE2, endothelial dysfunction and micro thrombosis, together with cytokine storm. We also discuss the ongoing EVs-based strategies for the treatment of COVID-19, including mesenchymal stem cell (MSC)-EVs, drug-EVs, vaccine-EVs, platelet-EVs, and others. This manuscript provides the foundation for the development of targeted drugs and vaccines for SARS-CoV-2 infections.
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Cell-free DNA (cfDNA) is easily accessible in peripheral blood and can be used as biomarkers for cancer diagnostics, prognostics, and therapeutics. The applications of cfDNA in various areas of cancer management are attracting attention. In this review article, we discuss the potential relevance of using cfDNA analysis in clinical oncology, particularly in cancer screening, early diagnosis, therapeutic evaluation, monitoring disease progression; and determining disease prognosis.
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Ácidos Cólicos/sangue , Vesícula Biliar/anormalidades , Cálculos Biliares/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/deficiência , Erros Inatos do Metabolismo de Esteroides/genética , Simportadores/deficiência , Adolescente , Animais , Ácidos Cólicos/metabolismo , Modelos Animais de Doenças , Feminino , Vesícula Biliar/patologia , Cálculos Biliares/metabolismo , Cálculos Biliares/patologia , Humanos , Lactente , Masculino , Camundongos , Camundongos Knockout , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Especificidade da Espécie , Erros Inatos do Metabolismo de Esteroides/sangue , Erros Inatos do Metabolismo de Esteroides/metabolismo , Erros Inatos do Metabolismo de Esteroides/patologia , Simportadores/genéticaRESUMO
5-Fluorouracil (5-FU)-based chemotherapy is the first-line option for patients with advanced colorectal cancer (CRC). However, the development of chemoresistance is the primary cause of treatment failure. Halofuginone (HF), a small molecule alkaloid derived from febrifugine, has been demonstrated to exert strong anti-proliferative effects. However, to the best of our knowledge, whether HF inhibits the progression of 5-FU-resistant human CRC HCT-15/FU cells, and the underlying mechanisms, remain unknown. In the present study, the effects of HF on HCT-15/FU cells were assessed in vitro. The results revealed that HF inhibited HCT-15/FU cell viability as demonstrated by the MTT and colony formation assays. Following treatment of HCT-15/FU cells with HF, the migratory and invasive capacities of the cells were significantly decreased. MicroRNA (miRNA/miR)-sequencing data, subsequent miRNA trend analysis and reverse transcription-quantitative PCR all demonstrated that miR-132-3p expression was increased following treatment with HF in a dose-dependent manner. Western blot analysis indicated that following treatment with HF, the expression levels of proteins associated with proliferation, invasion and metastasis in cells were markedly downregulated. These results suggested that HF inhibited the proliferation, invasion and migration of HCT-15/FU cells by upregulating the expression levels of miR-132-3p. Therefore, miR-132-3p may serve as a molecular marker, which may be used to predict CRC resistance to 5-FU, and HF may serve as a novel clinical treatment for 5-FU-resistant CRC.
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Integrins are the adhesion molecules and receptors of extracellular matrix (ECM). They mediate the interactions between cells-cells and cells-ECM. The crosstalk between cancer cells and their microenvironment triggers a variety of critical signaling cues and promotes the malignant phenotype of cancer. As a type of transmembrane protein, integrin-mediated cell adhesion is essential in regulating various biological functions of cancer cells. Recent evidence has shown that integrins present on tumor cells or tumor-associated stromal cells are involved in ECM remodeling, and as mechanotransducers sensing changes in the biophysical properties of the ECM, which contribute to cancer metastasis, stemness and drug resistance. In this review, we outline the mechanism of integrin-mediated effects on biological changes of cancers and highlight the current status of clinical treatments by targeting integrins.
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OBJECTIVES: The aim of the study was to explore the significance of sodium taurocholate cotransporting polypeptide (NTCP) deficiency and its clinical features in Chinese children presenting with isolated persistent hypercholanemia. METHODS: The exon and adjacent regions of SLC10A1, the gene encoding NTCP, were sequenced in 33 Chinese children presenting with isolated hypercholanemia. Clinical history and medical data were reviewed. Growth milestones were compared with the national standard. The serum direct bilirubin concentration at last follow-up was compared with age- and sex-matched controls. RESULTS: A variant, c.800C>T, p. S267F of SLC10A1 was detected in all subjects; 30 patients were homozygotes and 3 were compound heterozygotes. Nine patients presented with transient neonatal cholestasis, and 1 with a persistent mild conjugated hyperbilirubinemia. The serum direct bilirubin level in NTCP-deficient patients was significantly higher than age- and sex-matched controls even after the neonatal cholestasis stage (2.85â±â1.50 vs 1.49â±â0.70âµmol/L, Pâ=â0.00008). No growth delay or other severe long-term clinical consequences were observed. CONCLUSIONS: NTCP deficiency is the exclusive or major cause of isolated hypercholanemia in Han Chinese children, with c.800C>T the major contributing genetic variation. The defect may affect bilirubin metabolism and present as transient neonatal cholestasis and/or persistent mild conjugated hyperbilirubinmia, but with no apparent long-term clinical consequences.
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Bilirrubina , Transportadores de Ânions Orgânicos Dependentes de Sódio , Simportadores , Criança , Homozigoto , Humanos , Recém-Nascido , Transportadores de Ânions Orgânicos Dependentes de Sódio/deficiência , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Simportadores/deficiência , Simportadores/genéticaRESUMO
BACKGROUND: The diagnosis of bacterial infection is difficult in patients with acute-on-chronic liver failure (ACLF). AIM: To evaluate the diagnostic accuracy of widely used parameters for bacterial infection in ACLF and to develop a simple scoring system to improve diagnostic efficiency. METHODS: This was a retrospective study. Procalcitonin (PCT), white blood cells (WBC), proportion of neutrophils (N%), and C-reactive protein (CRP) were examined. Logistic regression was used to select variables for the scoring models and receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic value of different indices. RESULTS: This study included 386 patients with ACLF, 169 (43.78%) of whom had bacterial infection on admission. The area under the ROC (AUROC) of PCT, CRP, WBC and N% for the diagnosis of bacterial infection ranged from 0.637 to 0.692, with no significant difference between them. Logistic regression showed that only N%, PCT, and CRP could independently predict infection. A novel scoring system (infection score) comprised of N%, PCT and CRP was developed. The AUROC of the infection score was 0.740, which was significantly higher than that for the other four indices (infection score vs N%, PCT, CRP, and WBC, P = 0.0056, 0.0001, 0.0483 and 0.0008, respectively). The best cutoff point for the infection score was 4 points, with a sensitivity of 78.05%, a specificity of 55.29%, a positive predictive value of 57.91% and a negative predictive value of 76.16%. CONCLUSION: The infection score is a simple and useful tool for discriminating bacterial infection in ACLF.
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Insuficiência Hepática Crônica Agudizada , Infecções Bacterianas , Insuficiência Hepática Crônica Agudizada/diagnóstico , Infecções Bacterianas/diagnóstico , Biomarcadores , Proteína C-Reativa/análise , Calcitonina , Peptídeo Relacionado com Gene de Calcitonina , Humanos , Precursores de Proteínas , Curva ROC , Estudos RetrospectivosRESUMO
Cancer has been a major global health problem due to its high morbidity and mortality. While many chemotherapy agents have been studied and applied in clinical trials or in clinic, their application is limited due to its toxic side effects and poor tolerability. Monoclonal antibodies specific to the PD-1 and PD-L1 immune checkpoints have been approved for the treatment of various tumors. However, the application of PD-1/PD-L1 inhibitors remains suboptimal and thus another strategy comes in to our sight involving the combination of checkpoint inhibitors with other agents, enhancing the therapeutic efficacy. Various novel promising approaches are now in clinical trials, just as icing on the cake. This review summarizes relevant investigations on combinatorial therapeutics based on PD-1/PD-L1 inhibition.
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Exosomes affect the initiation and progression of cancers. In the tumor microenvironment, not only cancer cells, but also fibroblasts and immunocytes secrete exosomes. Exosomes act as a communicator between cells by transferring different cargos and microRNAs (miRNAs). Drug resistance is one of the critical factors affecting therapeutic effect in the course of cancer treatment. The currently known mechanisms of drug resistance include drug efflux, alterations in drug metabolism, DNA damage repair, alterations of energy programming, cancer stem cells and epigenetic changes. Many studies have shown that miRNA carried by exosomes is closely associated with the development of drug resistance mediated by the above-mentioned mechanisms. This review article will discuss how exosomal miRNAs regulate the drug resistance.
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The typical phenotype of arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome involves three cardinal symptoms as the name describes, harboring biallelic mutations on VPS33B or VIPAS39. Except for ARC syndrome, low gamma-glutamyltransferase (GGT) cholestasis often implies hereditary hepatopathy of different severity; however, some remain undiagnosed. Several monogenic defects typically with multiorgan manifestations may only present liver dysfunction at times, such as DGUOK defect and AGL defect. Previously, four VPS33B mutated cases were reported without arthrogryposis, or with less severe symptoms and longer lifespan, indicating the possibility of incomplete ARC phenotype of isolated hepatopathy. So we retrospectively reviewed all patients with confirmed VPS33B/VIPARS39 defect in our center and identified three presenting isolated low-GGT cholestasis with intractable pruritus. Distinguished from others with typical ARC phenotype, these patients did not suffer the other two typical characteristics, survived much longer, and shared a novel missense VPS33B variation c.1726T>C, p.Cys576Arg, causing declined protein expression and abolished interaction with VIPAS39 in-vitro. Serum bile acid profiles of our VPS33B/VIPAS39 mutated patients revealed similar changes to primary defect of bile salt export pump, among which those with isolated cholestasis phenotype had a higher level of total secondary bile acids than that with typical ARC phenotype, indicating the partial residual function of VPS33B.
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Subfamília B de Transportador de Cassetes de Ligação de ATP/deficiência , Colestase Intra-Hepática/genética , Mutação de Sentido Incorreto , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Ácidos e Sais Biliares/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Colestase Intra-Hepática/metabolismo , Regulação para Baixo , Feminino , Células HEK293 , Humanos , Masculino , Linhagem , Estudos RetrospectivosRESUMO
As a quinonemethide triterpenoid extracted from species of the Celastraceae and Hippocrateaceae, pristimerin has been shown potent anti-cancer effects. Specifically, it was found that pristimerin can affect many tumor-related processes, such as apoptosis, autophagy, migration and invasion, vasculogenesis, and drug resistance. Various molecular targets or signaling pathways are also involved, such as cyclins, reactive oxygen species (ROS), microRNA, nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK), and PI3K/AKT/mammalian target of rapamycin (mTOR) pathways. In this review, we will focus on the research about pristimerin-induced anti-cancer activities to achieve a deeper understanding of the targets and mechanisms, which offer evidences suggesting that pristimerin can be a potent anti-cancer drug.
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OBJECTIVES: The purpose of this study was to analyze the distribution and antimicrobial resistance of common bacterial pathogens causing neonatal septicemia based on a systematic review of published studies in China. METHODS: Articles on neonatal sepsis published in the Chinese literature from 2009 to 2014 were identified according to the inclusion and exclusion criteria. Data were extracted and analyzed using Comprehensive Meta-Analysis software. RESULTS: A total of 71 studies were included, in which a total of 8080 bacterial species were isolated from culture-positive blood samples. The pooled distribution rates of common bacterial pathogens were as follows: Staphylococcus 67.1% (95% confidence interval (CI) 63.3-70.6%), Enterococcus 4.1% (95% CI 3.5-4.8%), Streptococcus 2.3% (95% CI 1.6-3.2%), Escherichia coli 7.4% (95% CI 6.4-8.7%), Klebsiella 6.5% (95% CI 5.2-8.2%), Enterobacterium 2.3% (95% CI 1.9-2.8%), Acinetobacter 1.6% (95% CI 1.3-2.0%), Pseudomonas 1.7% (95% CI 1.3-2.2%). Among the Staphylococcus aureus strains isolated, more than 60% were methicillin-resistant (MRSA). In addition, over 50% of the Gram-negative isolates, including Escherichia and Klebsiella, were resistant to the commonly used third-generation cephalosporins. Most of the Gram-positive and Gram-negative bacteria isolated were sensitive to aminoglycosides, especially amikacin. CONCLUSIONS: It is concluded that Staphylococcus, especially coagulase-negative Staphylococcus, continues to be the principal organism responsible for neonatal septicemia in China; Enterobacteriaceae are common among the Gram-negative isolates. Significant numbers of MRSA and multidrug-resistant Gram-negative bacteria are being isolated as pathogens responsible for neonatal septicemia in China.