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Transient gene expression system is an important tool for rapid production of recombinant proteins in Chinese hamster ovary (CHO) cells. However, their low productivity is the main hurdle to overcome. An effective approach through which to obtain high protein yield involves targeting transcriptional, post-transcriptional events (PTEs), and culture conditions. Here, we investigated the effects of protein disulfide isomerase (PDI) and spliced X-box binding protein 1 (XBP-1s) co-overexpression combined with mild hypothermia on the transient yields of recombinant proteins in CHO cells. The results showed that the gene of interest (GOI) and the PDI/XBP-1s helper vector at a co-transfection ratio of 10:1 could obviously increase transient expression level of recombinant protein in CHO cells. However, PDI/XBP-1s overexpression had no significance effect on the mRNA levels of the recombinant protein, suggesting that it targeted PTEs. Moreover, the increased production was due to the enhancing of cell specific productivity, not related to cell growth, viability, and cell cycle. In addition, combined PDI/XBP-1s co-overexpression and mild hypothermia could further improve Adalimumab expression, compared to the control/37 °C and PDI/XBP-1s/37 °C, the Adalimumab volume yield of PDI/XBP-1s/33 °C increased by 203% and 142%, respectively. Mild hypothermia resulted in 3.52- and 2.33-fold increase in the relative mRNA levels of PDI and XBP-1s, respectively. In conclusion, the combination of PDI/XBP-1s overexpression and culture temperature optimization can achieve higher transient expression of recombinant protein, which provides a synergetic strategy to improve transient production of recombinant protein in CHO cells.
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Hipotermia , Factores de Transcripción , Cricetinae , Animales , Células CHO , Cricetulus , Factores de Transcripción/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteína Disulfuro Isomerasas/genética , Adalimumab/genética , Hipotermia/genética , Proteínas Recombinantes , Transfección , Transgenes , ARN MensajeroRESUMEN
In recent years, hazardous chemical incidents have occurred frequently, resulting in significant human casualties, property damage, and environmental pollution due to human or natural factors. Accurately mining the lessons learned from accumulating incident reports and constructing the knowledge graph for hazardous chemical incident management can assist managers in identifying patterns and analyzing common attributes, thereby preventing the recurrence of similar incidents. This article addresses the challenges of dispersed textual information, specialized vocabulary, and data formats in hazardous chemical incidents. We propose a novel entity-relation extraction model called CPBA-CLIM (content-position-based attention-cross-label intersect matching) to provide an accurate data foundation for constructing the hazardous chemical incident knowledge graph. The content-position-based attention module, based on content-position attention, incorporates contextual semantic information into the combined encoding of bidirectional encoder representations from the transformer's content and position to obtain dynamic word vectors that align with the thematic context of the text. Additionally, the cross-label intersect matching strategy evaluates the rationality of entity-relation interactions in sets containing potential overlaps, reducing the impact of entity-relation overlap on triplet extraction accuracy. Comparative experimental results on public datasets demonstrate the model's outstanding performance in overlapping triplets. Qualitative experiments on a self-constructed dataset integrate our model with ontology construction techniques, successfully establishing a knowledge graph for managing hazardous chemical incidents. This research effectively enhances the degree of automation and efficiency in knowledge graph construction, thus offering support and decision-making foundations for hazardous chemical safety management.
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Intracerebral hemorrhage (ICH) is one of the most devastating forms of stroke. However, studies on ICH at high altitude are insufficient. We aimed to compare the initial manifestations, imaging features and short-term functional outcomes of ICH at different altitudes, and further explore the effect of altitude on the severity and prognosis of ICH. We retrospectively recruited ICH patients from January 2018 to July 2021 from two centers at different altitudes in China. Information regarding to clinical manifestations, neuroimages, and functional outcomes at discharge were collected and analyzed. Association between altitude and initial severity, neuroimages, and short-term prognosis of ICH were also investigated. A total of 724 patients with 400 lowlanders and 324 highlanders were enrolled. Compared with patients from the plain, those at high altitude were characterized by more severe preliminary manifestations (P < 0.0001), larger hematoma volume (P < 0.001) and poorer short-term functional outcome (P < 0.0001). High altitude was independently associated with dependency at discharge (adjusted P = 0.024), in-hospital mortality (adjusted P = 0.049) and gastrointestinal hemorrhage incidence (adjusted P = 0.017). ICH patients from high altitude suffered from more serious initial manifestations and worse short-term functional outcome than lowlanders. Control of blood pressure, oxygen supplementation and inhibition of inflammation may be critical for ICH at high altitude.
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Hemorragia Cerebral , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/etiología , Accidente Cerebrovascular/complicaciones , Pronóstico , China/epidemiología , Hematoma/diagnóstico por imagenRESUMEN
Background: Depression rates among adolescents have risen dramatically over the past decade. Therefore, preventing depression among adolescents is particularly important. Differences in lifestyle habits may play a role in depression. Purpose: This study aimed to explore the influence of living habits on depression levels among rural middle school students in Northeast China and to provide a theoretical basis for developing interventions to reduce depression levels in middle school students. Methods: A total of 296 middle school students aged 13-15 years from Benxi City, Northeast China completed the anthropometric measurements, Physical Activity Scale-3 (PARS-3), and the Self-Rating Depression Scale (SDS). Their average screen time in the most recent week, parents' education level, and monthly family income were collected through a questionnaire. Results: Females had higher depression scores than males (41.0 ± 6.9 vs. 37.9 ± 8.0). Physical activity (ß = -0.38, t = -7.06, P < 0.01), family income (ß = -0.20, t = -4.07, P < 0.01), screen time (ß = 0.16, t = 3.34, P < 0.01), age (ß = 0.15, t = 3.16, P < 0.01), sex (ß = -0.13, t = -2.74, P < 0.01), and sleep quality (ß = -0.08, t = -1.87, P < 0.01) are important factors related to depression levels. Conclusion: The preliminary analysis results showed that among middle school students in rural Northeast China, the depression level of females was significantly higher than that of males. Poor quality sleep, low levels of physical activity, low household income, and long screen time were positively associated with depression. Therefore, strengthening physical activity, improving sleep quality, and reducing screen time are of clinical relevance in preventing and reducing depression.
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Depresión , Estudiantes , Masculino , Femenino , Adolescente , Humanos , Depresión/epidemiología , Estilo de Vida , Encuestas y Cuestionarios , Ejercicio FísicoRESUMEN
The human cytomegalovirus major immediate early gene (CMV) promoter is currently the most preferred promoter for recombinant therapeutic proteins (RTPs) production in CHO cells. To enhance the production of RTPs, five synthetic enhancers including multiple transcription factor regulatory elements (TFREs) were evaluated to enhance recombinant protein level in transient and stably transfected CHO cells. Compared with the control, four elements can enhance the report genes expression under both two transfected states. Further, the function of these four enhancers on human serum albumin (HSA) were investigated. We found that the transient expression can increase by up to 1.5 times, and the stably expression can maximum increase by up to 2.14 times. The enhancement of transgene expression was caused by the boost of their corresponding mRNA levels. Transcriptomics analysis was performed and found that transcriptional activation and cell cycle regulation genes were involved. In conclusion, optimization of enhancers in the CMV promoter could increase the production yield of transgene in transfected CHO cells, which has significance for developing high-yield CHO cell expression system.
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Objectives To find out the prevalence rate of pre-myopia among primary school students in the Mianyang Science City Area, analyze its related risk factors, and thus provide a reference for local authorities to formulate policies on the prevention and control of myopia for primary school students. Methods From September to October 2021, Cluster sampling was adopted by our research group to obtain the vision levels of primary school students employing a diopter test in the Science City Area. In addition, questionnaires were distributed to help us find the risk factors associated with pre-myopia. Through the statistical analysis, we identify the main risk factors for pre-myopia and propose appropriate interventions. Results The prevalence rate of pre-myopia among primary school students in the Science City Area was 45.27% (1020/2253), of which 43.82% were boys and 46.92% were girls, with no statistically significant difference in the prevalence rate of myopia between boys and girls (2 =2.171, P=0.141). The results of the linear trend test showed that the prevalence rate of pre-myopia tends to decrease with increasing age (Z=296.521, P=0.000). Logistic regression analysis demonstrated that the main risk factors for pre-myopia were having at least one parent with myopia, spending less than 2 hours a day outdoors, using the eyes continuously for more than 1 hour, looking at electronic screens for more than 2 hours, and having an improper reading and writing posture. Conclusion The Science City Area has a high prevalence rate of pre-myopia among primary school students. It is proposed that students, schools, families, and local authorities work together to increase the time spent outdoors, reduce digital screens and develop scientific use of eye habits.
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Background: Pathological progression from non-alcoholic fatty liver disease (NAFLD) to liver fibrosis (LF) to hepatocellular carcinoma (HCC) is a common dynamic state in many patients. Curcumin, a dietary supplement derived from the turmeric family, is expected to specifically inhibit the development of this progression. However, there is a lack of convincing evidence. Methods: The studies published until June 2023 were searched in PubMed, Web of Science, Embase, and the Cochrane Library databases. The SYstematic Review Center for Laboratory animal Experimentation (SYRCLE) approach was used to evaluate the certainty of evidence. StataSE (version 15.1) and Origin 2021 software programs were used to analyze the critical indicators. Results: Fifty-two studies involving 792 animals were included, and three disease models were reported. Curcumin demonstrates a significant improvement in key indicators across the stages of NAFLD, liver fibrosis, and HCC. We conducted a detailed analysis of common inflammatory markers IL-1ß, IL-6, and TNF-α, which traverse the entire disease process. The research results reveal that curcumin effectively hinders disease progression at each stage by suppressing inflammation. Curcumin exerted hepatoprotective effects in the dose range from 100 to 400 mg/kg and treatment duration from 4 to 10 weeks. The mechanistic analysis reveals that curcumin primarily exerts its hepatoprotective effects by modulating multiple signaling pathways, including TLR4/NF-κB, Keap1/Nrf2, Bax/Bcl-2/Caspase 3, and TGF-ß/Smad3. Conclusion: In summary, curcumin has shown promising therapeutic effects during the overall progression of NAFLD-LF-HCC. It inhibited the pathological progression by synergistic mechanisms related to multiple pathways, including anti-inflammatory, antioxidant, and apoptosis regulation.
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In eukaryotes, the localization of small ribosomal subunits to mRNA transcripts requires the translation of Kozak elements at the starting site. The sequence of Kozak elements affects the translation efficiency of protein synthesis. However, whether the upstream nucleotide of Kozak sequence affects the expression of recombinant proteins in Chinese hamster ovary (CHO) cells remains unclear. In order to find the optimal sequence to enhance recombinant proteins expression in CHO cells, -10 to +4 sequences around ATG in 100 CHO genes were compared, and the extended Kozak elements with different translation intensities were constructed. Using the classic Kozak element as control, the effects of optimized extended Kozak elements on the secreted alkaline phosphatase (SEAP) and human serum albumin (HSA) gene were studied. The results showed that the optimized extended Kozak sequence can enhance the stable expression level of recombinant proteins in CHO cells. Furthermore, it was found that the increased expression level of the recombinant protein was not related with higher transcription level. In summary, optimizing extended Kozak elements can enhance the expression of recombinant proteins in CHO cells, which contributes to the construction of an efficient expression system for CHO cells.
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Fosfatasa Alcalina , Cricetulus , Proteínas Recombinantes , Células CHO , Animales , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Cricetinae , HumanosRESUMEN
Vaccines represent an effective tool for controlling disease infection. As a key component of vaccines, many types of adjuvants have been developed and used today. This study is designed to investigate the efficacy of single-walled carbon nanotubes (SWCNTs) as a new adjuvant. The results showed that SWCNT could adsorb the antigen by intermolecular action, and the adsorption rate was significantly higher after dispersion of the SWCNTs in a sonic bath. The titer of specific antibody of mice in the SWCNTs group was higher than that of the mice in the antigen control group, confirming the adjuvant efficacy of SWCNTs. During immunisation, the specific antibody was detected earlier in the mice of the SWCNTs group, especially when the amount of antigen was reduced. And it was proved that the titer of antibodies was higher after subcutaneous and intraperitoneal injection compared to intramuscular injection. Most importantly, the mice immunised with SWCNTs showed almost the same level of immunity as the mice in the FCA (Freund's complete adjuvant) group, indicating that the SWCNTs were an effective adjuvant. In addition, the mice in the SWCNT group maintained antibody levels for 90 days after the last booster vaccination and showed a good state of health during the observed period. We also found that the SWCNTs were able to induce macrophages activation and enhance antigen uptake by mouse peritoneal macrophages.
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Objective@#To understand the prevalence rate of pre myopia among preschoolers and its associated factors, so as to provide a basis for the formulation of myopia prevention and control policies.@*Methods@#In May 2022, a tatol of 1 070 preschoolers in the Science City Area of Mianyang City were selected by using a cluster sampling method. The visual acuity of preschool children was obtained through refractive examination, and a questionnaire survey was conducted to investigate associated factors of myopia in the preclinical stage by Chi square test and multivariate Logistic regression analysis.@*Results@#The prevalence rate of pre myopia in preschoolers was 67.01%, including 66.30% for boys and 67.76% for girls. There was no significant difference by sex( χ 2=0.26, P > 0.05). Multivariate Logistic regression analysis showed that at least one parent with myopia, too much near work activities, time spent on outdoor activity <2 h per day, lack of sleep, and screen time ≥1 h per day were positively correlated with the occurrence of pre myopia( OR =1.62, 1.46, 1.46, 1.38, 1.53, P <0.01).@*Conclusion@#The prevalence of pre myopia among preschool children in Science City Area is high. It is suggested that parents, kindergartens and relevant departments should pay attention to the visual status of preschoolers, increase outdoor activities, ensure adequate sleep and train preschoolers to develop scientific eye hygiene habits.
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Objective@#To understand the prevalence rate of pre myopia among preschoolers and its associated factors, so as to provide a basis for the formulation of myopia prevention and control policies.@*Methods@#In May 2022, a tatol of 1 070 preschoolers in the Science City Area of Mianyang City were selected by using a cluster sampling method. The visual acuity of preschool children was obtained through refractive examination, and a questionnaire survey was conducted to investigate associated factors of myopia in the preclinical stage by Chi square test and multivariate Logistic regression analysis.@*Results@#The prevalence rate of pre myopia in preschoolers was 67.01%, including 66.30% for boys and 67.76% for girls. There was no significant difference by sex( χ 2=0.26, P > 0.05). Multivariate Logistic regression analysis showed that at least one parent with myopia, too much near work activities, time spent on outdoor activity <2 h per day, lack of sleep, and screen time ≥1 h per day were positively correlated with the occurrence of pre myopia( OR =1.62, 1.46, 1.46, 1.38, 1.53, P <0.01).@*Conclusion@#The prevalence of pre myopia among preschool children in Science City Area is high. It is suggested that parents, kindergartens and relevant departments should pay attention to the visual status of preschoolers, increase outdoor activities, ensure adequate sleep and train preschoolers to develop scientific eye hygiene habits.