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1.
RSC Adv ; 13(51): 36200-36208, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090065

RESUMO

Actinomycins are known for their anti-tumor, antibacterial and antiviral activities, and in particular for the ability of actinomycin D as a clinical drug to treat a variety of cancers. In our ongoing work to obtain novel natural products from endophytic actinomycetes derived from traditional Chinese herbs, we identified the potential to produce actinomycins in YINM00002, a Kitasatospora strain derived from Polygonatum kingianum. According to genome mining, we isolated actinomycins D and V (1 and 2) and small amounts of 4-methyl-3-hydroxyanthranilic acid (4-MHA) derivates (3 and 4) from strain fermentation broth. The presence of actinrhater A (3) and actinrhater B (4) reveals a mysterious shunt pathway in the early stages of actinomycin D biosynthesis. Our study provides a fresh perspective for further discovery and modification of novel actinomycins.

2.
Birth Defects Res ; 115(18): 1770-1779, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776548

RESUMO

BACKGROUND: Maternal diabetes increases the risk for neural tube defects (NTDs). It is unclear if miRNAs, senescence, and DNA damage are involved in this process. In this study, we used neural stem cells as an in vitro proxy of embryonic neuroepithelium to investigate whether high glucose triggers neural stem cell senescence and DNA damage by upregulating miR-200c, which may be responsible for NTDs. METHODS: C17.2 neural stem cells were cultured with normal glucose (5 mM) or high glucose (≥16.7 mM) at different doses and time points for detecting miR-200c levels, markers of senescence and DNA damage. Neural stem cells were exposed to antioxidant SOD1 mimetic Tempol and high glucose for 48 h to test roles of oxidative stress on the miR-200c, senescence, and DNA damage levels. An miR-200c mimic and an inhibitor were transfected into neural stem cells to increase or decrease miR-200c activities. RESULTS: High glucose upregulated miR-200c in neural stem cells. A time course study of the effect of high glucose revealed that miR-200c initially increased at 12 h and reached its zenith at 18 h. Tempol reduced miR-200c levels caused by high glucose. High glucose induced markers of senescence and DNA damage in neural stem cells. Tempol abolished high glucose-induced markers of senescence and DNA damage. The miR-200c inhibitor suppressed high glucose-induced markers of senescence and DNA damage. Treatment with miR-200c mimic imitates high glucose-induced markers of senescence and DNA damage. CONCLUSIONS: We show that high glucose increases miR-200c, which contributes to cellular senescence and DNA damage in neural stem cells and provides a potential pathway for maternal diabetes-induced neural tube defects.


Assuntos
Diabetes Gestacional , MicroRNAs , Células-Tronco Neurais , Defeitos do Tubo Neural , Gravidez , Feminino , Humanos , Células-Tronco Neurais/metabolismo , Senescência Celular/genética , MicroRNAs/genética , Defeitos do Tubo Neural/genética , Glucose/farmacologia , Glucose/metabolismo , Dano ao DNA
3.
Cancer Biol Ther ; 19(12): 1162-1173, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30260270

RESUMO

Recently, some studies have placed additional research focus on microRNAs (miRNAs) in a bid to discover novel therapeutic approaches for cervical cancer (CC), which is one of the most common female reproductive tract malignancies with high rates of morbidity and mortality. Hence, the aim of the present study was to evaluate the ability of miR-129-5p to influence cell angiogenesis, invasion and migration by targeting ZIC2 through the Hedgehog signaling pathway in CC. Both CC and adjacent normal tissues were extracted from 87 eligible participating patients with CC. Measurements of the levels of miR-129-5p, mRNA and protein levels of ZIC2, sonic Hedgehog (Shh), Gli1, and Gli2 and levels of CXCL1, VEGF and Ang2 were determined accordingly. An angiogenesis assay was performed to evaluate cell angiogenesis in vitro, while a scratch test and transwell assay were adopted for cell invasion and migration determination. Lastly, tumor formation within nude mice was performed in order to analyze angiogenesis and tumor growth among the nude mice in vivo. The findings revealed that upregulation of miR-129-5p resulted in the decrease in the mRNA and protein levels of ZIC2, Shh, Gli1, Gli2, as well as reduced levels of CXCL1, VEGF and Ang2. Moreover, up-regulation of miR-129-5p was determined to inhibit CC cell angiogenesis ability in vitro, in addition to the processes of cell migration, and invasion. Finally, up-regulation of miR-129-5p was observed to inhibit the tumor growth and angiogenesis ability of nude mice in vivo. The results of the present study provided evidence suggesting that overexpressed miR-129-5p prevents angiogenesis and inhibits cell migration and invasion by means of negatively targeting ZIC2 through suppression of the Hedgehog signaling pathway in CC. Thus, highlighting the promise of miR-129-5p as a novel target for treating CC is promising.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(5): 1444-1448, 2017 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-29070122

RESUMO

OBJECTIVE: To explore the levels of T-lymphocyte subsets and IL-17, IL-35, IFN-γ in peripheral blood of patients with multiple myeloma(MM) and their clinical significance. METHODS: A total of 86 MM patients in our hospital from January 2014 to January 2017 were enrolled in MM group and 30 healthy persons were enrolled in control group, the CD4+/CD8+ T cells ratio, CD4+CD25high/+ CD127low/- Treg level in peripheral blood were detected by flow cytometer. The levels of IL-17, IL-35 and IFN-γ in peripheral serum were detected by ELISA, and the differences of detected indicators between different groups were compared. RESULTS: Compared with control group, the proportion of CD4+ T cells and CD4+/CD8+ T cells ratio decreased, the proportion of CD8+ T cells and Treg increased in MM group. The differences of T lymphocyte subsets level between group III stage of MM and control group were statistically significant (P<0.05). With enhancing of clinical stages, Treg level showed a increasing trend, especially in III stage (P<0.05), the serum level of IL-17 as followed in turn: III stage>II stage>I stage>control, the serum level of IL-35 and IFN-γ as followed in turn: control>I stage>II stage>III stage (P<0.05). In terms of disease status, the propurtion of Treg cells as fllowed in turn: disease progression stage>stable stage>control (P<0.05), the serum level of IL-17 as followed in turn also: disease progression stage>stable stage (P<0.05), while the serum level of IL-35 and IFN-γ as followed in turn: control>disease table stage>progression stage (P<0.05). CONCLUSION: The abnomal level of T-lymphocyte subsets, Treg, IL-17, IL-35 and IFN-γ are related with progression and prognosis of MM patients.


Assuntos
Linfócitos T CD4-Positivos , Interferon gama/sangue , Interleucina-17/sangue , Interleucinas/sangue , Mieloma Múltiplo/imunologia , Humanos , Subpopulações de Linfócitos T , Linfócitos T Reguladores
5.
PLoS One ; 7(3): e33030, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22438889

RESUMO

Helicobacter pylori infection reprograms host gene expression and influences various cellular processes, which have been investigated by cDNA microarray using in vitro culture cells and in vivo gastric biopsies from patients of the Chronic Abdominal Complaint. To further explore the effects of H. pylori infection on host gene expression, we have collected the gastric antral mucosa samples from 6 untreated patients with gastroscopic and pathologic confirmation of chronic superficial gastritis. Among them three patients were infected by H. pylori and the other three patients were not. These samples were analyzed by a microarray chip which contains 14,112 cloned cDNAs, and microarray data were analyzed via BRB ArrayTools software and Ingenuity Pathways Analysis (IPA) website. The results showed 34 genes of 38 differentially expressed genes regulated by H. pylori infection had been annotated. The annotated genes were involved in protein metabolism, inflammatory and immunological reaction, signal transduction, gene transcription, trace element metabolism, and so on. The 82% of these genes (28/34) were categorized in three molecular interaction networks involved in gene expression, cancer progress, antigen presentation and inflammatory response. The expression data of the array hybridization was confirmed by quantitative real-time PCR assays. Taken together, these data indicated that H. pylori infection could alter cellular gene expression processes, escape host defense mechanism, increase inflammatory and immune responses, activate NF-κB and Wnt/ß-catenin signaling pathway, disturb metal ion homeostasis, and induce carcinogenesis. All of these might help to explain H. pylori pathogenic mechanism and the gastroduodenal pathogenesis induced by H. pylori infection.


Assuntos
Gastrite/genética , Infecções por Helicobacter/genética , Helicobacter pylori , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Doença Crônica , Análise por Conglomerados , Mucosa Gástrica/metabolismo , Gastrite/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Infecções por Helicobacter/metabolismo , Helicobacter pylori/patogenicidade , Interações Hospedeiro-Patógeno/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas/genética , Proteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/genética , Oligoelementos/metabolismo , Transcrição Gênica
6.
J Hazard Mater ; 198: 182-7, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22061442

RESUMO

The aims of the present study were set out to measure size distributions and estimate workers' exposure concentrations of oil mist nanoparticles in three selected workplaces of the forming, threading, and heat treating areas in a fastener manufacturing plant by using a modified electrical aerosol detector (MEAD). The results were further compared with those simultaneously obtained from a nanoparticle surface area monitor (NSAM) and a scanning mobility particle sizer (SMPS) for the validation purpose. Results show that oil mist nanoparticles in the three selected process areas were formed mainly through the evaporation and condensation processes. The measured size distributions of nanoparticles were consistently in the form of uni-modal. The estimated fraction of nanoparticles deposited on the alveolar (AV) region was consistently much higher than that on the head airway (HD) and tracheobronchial (TB) regions in both number and surface area concentration bases. However, a significant difference was found in the estimated fraction of nanoparticles deposited on each individual region while different exposure metrics were used. Comparable results were found between results obtained from both NSAM and MEAD. After normalization, no significant difference can be found between the results obtained from SMPS and MEAD. It is concluded that the obtained MEAD results are suitable for assessing oil mist nanoparticle exposures.


Assuntos
Indústrias , Nanopartículas , Óleos , Aerossóis , Poluentes Ocupacionais do Ar/toxicidade , Humanos , Exposição Ocupacional , Tamanho da Partícula , Sistema Respiratório/efeitos dos fármacos
7.
Environ Sci Technol ; 44(17): 6767-74, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20704279

RESUMO

The present study was set out to characterize nanoparticle exposures in three selected workplaces of the packaging, warehouse, and pelletizing in a carbon black manufacturing plant using a newly developed modified electrical aerosol detector (MEAD). For confirmation purposes, the MEAD results were compared with those simultaneously obtained from a nanoparticle surface area monitor (NSAM) and a scanning mobility particle sizer (SMPS). We found that workplace background nanoparticle concentrations were mainly coming from the outdoor environment. Size distributions of nanoparticles for the three selected process areas during the work hours were consistently in the form of bimodel. Unlike nanoparticles of the second mode (simply contributed by the process emissions), particles of the first mode could be also contributed by the forklift exhaust or fugitive emissions of heaters. The percents of nanoparticles deposited on the alveolar (A) region were much higher than the other two regions of the head airway (H), tracheobronchial (TB) for all selected workplaces in both number and surface area concentrations. However, significant differences were found in percents of nanoparticles deposited on each of the three regions while different exposure metrics were adopted. Both NSAM and MEAD obtained quite comparable results. No significant difference can be found between the results obtained from SMPS and MEAD after being normalized. Considering the MEAD is less expensive, less bulky, and easy to use, our results further support the suitability of using MEAD in the field for nanoparticle exposure assessments.


Assuntos
Equipamentos e Provisões Elétricas , Monitoramento Ambiental/instrumentação , Indústrias , Exposição por Inalação/análise , Nanopartículas/análise , Sistema Respiratório/anatomia & histologia , Fuligem/efeitos adversos , Aerossóis/análise , Poluentes Ocupacionais do Ar/análise , Humanos , Tamanho da Partícula , Reprodutibilidade dos Testes , Fuligem/administração & dosagem , Propriedades de Superfície , Recursos Humanos , Local de Trabalho
8.
Environ Int ; 34(7): 971-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18423596

RESUMO

This study first assessed workers' inhalatory and dermal exposures to polycyclic aromatic hydrocarbons (PAHs) contained in oil mists. Then, their resultant lung cancer and skin cancer risks were estimated. Finally, control strategies were initiated from the health-risk management aspect. All threading workers in a fastener manufacturing plant were included. 16 inhalatory and 88 dermal PAH exposure samples were collected. Results show that the inhalatory gas phase total PAH exposure level (8.60 x 10(4) ng/m3) was much higher than that of particle phase (2.30 x 10(3) ng/m3). Workers' mean inhalatory exposure level (8.83 x 10(4) ng/m3) was lower, but its corresponding 1-sided upper 95% confidence level (UCL1,95% = 1.02 x 10(5) ng/m3) was higher than the time-weighted average permissible exposure level (PEL-TWA) regulated in Taiwan for PAHs (1.00 x 10(5) ng/m3). The mean whole body total PAHs dermal exposure levels was 5.44 x 10(6) ng/day and the top five exposed surface areas were lower arm, hand, upper arm, neck, and head/front. The estimated lifetime skin cancer risk (9.72 x 10(-3)) was lower than that of lung cancer risk (1.64 x 10(-2)), but both were higher than the significant risk level (10(-3)) defined by the US Supreme Court in 1980. The installation of a local exhaust ventilation system at the threading machine should be considered as the first priority measurement because both lung and skin cancer risks can be reduced simultaneously. If the personal protection equipment would be adopted in the future, both respiratory protection equipment and protective clothing should be used simultaneously.


Assuntos
Indústrias , Exposição Ocupacional , Pele/efeitos dos fármacos , Exposição por Inalação , Compostos Policíclicos/toxicidade
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