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Flavonoid compounds are widely present in various organs and tissues of different plants, playing important roles when plants are exposed to abiotic stresses. Different types of flavonoids are biosynthesized by a series of enzymes that are encoded by a range of gene families. In this study, a total of 63 flavonoid pathway genes were identified from the genome of Medicago truncatula. Gene structure analysis revealed that they all have different gene structure, with most CHS genes containing only one intron. Additionally, analysis of promoter sequences revealed that many cis-acting elements responsive to abiotic stress are located in the promoter region of flavonoid pathway genes. Furthermore, analysis on M. truncatula gene chip data revealed significant changes in expression level of most flavonoid pathway genes under the induction of salt or drought treatment. qRT-PCR further confirmed significant increase in expression level of several flavonoid pathway genes under NaCl and mannitol treatments, with CHS1, CHS9, CHS10, F3'H4 and F3'H5 genes showing significant up-regulation, indicating they are key genes in response to abiotic stress in M. truncatula. In summary, our study identified key flavonoid pathway genes that were involved in salt and drought response, which provides important insights into possible modification of flavonoid pathway genes for molecular breeding of forage grass with improved abiotic resistance.
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The reciprocal modulation between the CXCL12/CXCR4/ACKR3 axis and the STAT3 signaling pathway plays a crucial role in the progression of various diseases and neoplasms. Activation of the CXCL12/CXCR4/ACKR3 axis triggers the STAT3 pathway through multiple mechanisms, while the STAT3 pathway also regulates the expression of CXCL12. This review offers a thorough and systematic analysis of the reciprocal regulatory mechanisms between the CXCL12/CXCR4/ACKR3 signaling axis and the STAT3 signaling pathway in the context of diseases, particularly tumors. It explores the potential clinical applications in tumor treatment, highlighting possible therapeutic targets and novel strategies for targeted tumor therapy.
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Quimiocina CXCL12 , Neoplasias , Receptores CXCR4 , Fator de Transcrição STAT3 , Transdução de Sinais , Humanos , Fator de Transcrição STAT3/metabolismo , Receptores CXCR4/metabolismo , Quimiocina CXCL12/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Receptores CXCR/metabolismo , Receptores CXCR/genéticaRESUMO
BACKGROUND: Roux-en-Y reconstruction is a common anastomosis technique during gastrectomy in gastric cancer. There is a lack of studies on gallstones after Roux-en-Y reconstruction gastrectomy. This study investigated the incidence and potential risk factors associated with gallstones after Roux-en-Y reconstructive gastrectomy in gastric cancer. METHODS: The study analyzed data from gastric cancer who underwent radical gastrectomy and Roux-en-Y reconstruction at two hospitals between January 2014 and December 2020. The patients fall into distal and total gastrectomy groups based on the extent of gastrectomy. The cumulative event probability curve was plotted using the Kaplan-Meier, and differences in gallstone between groups were evaluated using the Log-Rank. Propensity score matching was applied to construct a balanced total versus distal gastrectomies cohort. A Cox regression was employed to analyze the risk factors for gallstones after Roux-en-Y reconstructive gastrectomy in gastric cancer. Further subgroup analysis was performed. RESULTS: Five hundred thirty-one patients were included in this study, 201 in the distal gastrectomy group and 330 in the total gastrectomy. During the follow-up, gallstones occurred in 170 cases after gastrectomy, of which 145 cases accounted for 85.29% of all stones in the first two years after surgery. Then, to reduce the impact of bias, a 1:1 propensity score matching analysis was performed on the two groups of patients. A total of 344 patients were evaluated, with each subgroup comprising 172 patients. In the matched population, the Cox regression analysis revealed that females, BMI ≥23 kg/m 2 , total gastrectomy, No.12 lymph node dissection, and adjuvant chemotherapy were risk factors for gallstones after Roux-en-Y reconstructive gastrectomy. Subgroup analysis showed that open surgery further increased the risk of gallstones after total gastrectomy. CONCLUSION: The incidence of gallstones increased significantly within 2years after Roux-en-Y reconstructive gastrectomy for gastric cancer. Patients with these risk factors should be followed closely after gastrectomy to avoid symptomatic gallstones.
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Anastomose em-Y de Roux , Cálculos Biliares , Gastrectomia , Complicações Pós-Operatórias , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Gastrectomia/efeitos adversos , Gastrectomia/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Cálculos Biliares/cirurgia , Cálculos Biliares/epidemiologia , Cálculos Biliares/etiologia , Incidência , Anastomose em-Y de Roux/efeitos adversos , Idoso , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Pontuação de Propensão , Estudos de Coortes , AdultoRESUMO
BACKGROUND: Extrahepatic cholangiocarcinoma sarcoma is extremely rare in clinical practice. These cells consist of both epithelial and mesenchymal cells. Patient-derived cell lines that maintain tumor characteristics are valuable tools for studying the molecular mechanisms associated with carcinosarcoma. However, cholangiocarcinoma sarcoma cell lines are not available in cell banks. AIM: To establish and characterize a new extrahepatic cholangiocarcinoma sarcoma cell line, namely CBC2T-2. METHODS: We conducted a short tandem repeat (STR) test to confirm the identity of the CBC2T-2 cell line. Furthermore, we assessed the migratory and invasive properties of the cells and performed clonogenicity assay to evaluate the ability of individual cells to form colonies. The tumorigenic potential of CBC2T-2 cells was tested in vivo using non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice. The cells were injected subcutaneously and tumor formation was observed. In addition, immunohistochemical analysis was carried out to examine the expression of epithelial marker CK19 and mesenchymal marker vimentin in both CBC2T-2 cells and xenografts. The CBC2T-2 cell line was used to screen the potential therapeutic effects of various clinical agents in patients with cholangiocarcinoma sarcoma. Lastly, whole-exome sequencing was performed to identify genetic alterations and screen for somatic mutations in the CBC2T-2 cell line. RESULTS: The STR test showed that there was no cross-contamination and the results were identical to those of the original tissue. The cells showed round or oval-shaped epithelioid cells and mesenchymal cells with spindle-shaped or elongated morphology. The cells exhibited a high proliferation ratio with a doubling time of 47.11 h. This cell line has migratory, invasive, and clonogenic abilities. The chromosomes in the CBC2T-2 cells were polyploidy, with numbers ranging from 69 to 79. The subcutaneous tumorigenic assay confirmed the in vivo tumorigenic ability of CBC2T-2 cells in NOD/SCID mice. CBC2T-2 cells and xenografts were positive for both the epithelial marker, CK19, and the mesenchymal marker, vimentin. These results suggest that CBC2T-2 cells may have both epithelial and mesenchymal characteristics. The cells were also used to screen clinical agents in patients with cholangiocarcinoma sarcoma, and a combination of paclitaxel and gemcitabine was found to be the most effective treatment option. CONCLUSION: We established the first human cholangiocarcinoma sarcoma cell line, CBC2T-2, with stable biogenetic traits. This cell line, as a research model, has a high clinical value and would facilitate the understanding of the pathogenesis of cholangiocarcinoma sarcoma.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Sarcoma , Camundongos , Animais , Humanos , Vimentina , Linhagem Celular Tumoral , Camundongos SCID , Camundongos Endogâmicos NOD , Sarcoma/genética , Sarcoma/patologia , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologiaRESUMO
Background: Recent studies have shown that bile acids are essential in irritable bowel syndrome (IBS) pathology, and cholecystectomy has direct effects on bile acid metabolism. However, whether cholecystectomy increases the risk of IBS remains unclear. We aimed to investigate the association between cholecystectomy and IBS risk in the UK Biobank (UKB). Methods: This study is a prospective analysis of 413,472 participants who were free of IBS, inflammatory bowel disease, cancer, or common benign digestive tract diseases. We identified incidents of IBS through self-reporting or links to primary healthcare and hospitalization data. We evaluated hazard ratios (HRs) adjusted for sociodemographic characteristics, health behaviours, comorbidities, and medications. Results: During a median follow-up period of 12.7 years, we observed 15,503 new cases of IBS. Participants with a history of cholecystectomy had a 46% higher risk of IBS than those without (HR = 1.46, 95% CI: 1.32-1.60), and further subtype analysis showed that the risk of IBS with diarrhoea was significantly higher than the risk of IBS without diarrhoea (HR = 1.71, 95% CI: 1.30-2.25 vs. HR = 1.42, 95% CI: 1.28-1.58). The overall covariate-adjusted HRs for IBS were similar between the group with both cholecystectomy and gallstones (HR = 1.45, 95% CI: 1.32-1.58) and the group with cholecystectomy without gallstones (HR = 1.50, 95% CI: 1.36-1.67) when the group without both cholecystectomy and gallstones was used as a reference. The overall covariate-adjusted HR was not significantly different in the group without cholecystectomy with gallstones (HR = 1.18, 95% CI: 0.95-1.47). The positive association of cholecystectomy with IBS risk did not change when stratifying the data based on age, sex, BMI, smoking, alcohol consumption, healthy diet, quality sleep, physical activity, type 2 diabetes, hypertension, hyperlipidaemia, mental illness, NSAID intake, or acid inhibitor intake. Sensitivity analyses, including propensity score matching analysis and lagging the exposure for two or four years, indicated that the effects were robust. Conclusion: Cholecystectomy was associated with a higher risk of IBS, especially IBS with diarrhoea. Additional prospective randomized controlled and experimental studies are warranted to further validate the association and to explore the relevant biological mechanisms.
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Background: Gut microbiome dysbiosis has been implicated in various gastrointestinal and extra-gastrointestinal diseases, but evidence on the efficacy and safety of fecal microbiota transplantation (FMT) for therapeutic indications remains unclear. Methods: The gutMDisorder database was used to summarize the associations between gut microbiome dysbiosis and diseases. We performed an umbrella review of published meta-analyses to determine the evidence synthesis on the efficacy and safety of FMT in treating various diseases. Our study was registered in PROSPERO (CRD42022301226). Results: Gut microbiome dysbiosis was associated with 117 gastrointestinal and extra-gastrointestinal. Colorectal cancer was associated with 92 dysbiosis. Dysbiosis involving Firmicutes (phylum) was associated with 34 diseases. We identified 62 published meta-analyses of FMT. FMT was found to be effective for 13 diseases, with a 95.56% cure rate (95% CI: 93.88-97.05%) for recurrent Chloridoids difficile infection (rCDI). Evidence was high quality for rCDI and moderate to high quality for ulcerative colitis and Crohn's disease but low to very low quality for other diseases. Conclusion: Gut microbiome dysbiosis may be implicated in numerous diseases. Substantial evidence suggests FMT improves clinical outcomes for certain indications, but evidence quality varies greatly depending on the specific indication, route of administration, frequency of instillation, fecal preparation, and donor type. This variability should inform clinical, policy, and implementation decisions regarding FMT.
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We construct the two-dimensional (2D) excitonic solar cells based on type II vdW heterojunctions of Janus III-VI chalcogenide monolayers and investigate the performance of the device using the first principle. The calculated solar energy absorbance of In2SSe/GaInSe2and In2SeTe/GaInSe2heterojunctions is the order of 105cm-1. The predicted photoelectric conversion efficiency of the In2SeTe/GaInSe2heterojunction can reach up to 24.5%, which compares favorably with other previously studied 2D heterojunctions. The excellent performance of In2SeTe/GaInSe2heterojunction originates from the fact that the built-in electric field at the interface of In2SeTe/GaInSe2promote the flow of the photogenerated electrons. The results suggest that 2D Janus Group-III chalcogenide heterojunction can be a good candidate for new optoelectronic nanodevices.
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Aging has been recently reported to promote lung cancer initiation and progression. Senescent fibroblasts gain a cancer-associated fibroblast (CAF) phenotype, and exert a powerful influence on cancer behavior, such as tumor cell growth and metastasis. However, mechanisms linking fibroblast senescence with CAF activation remain poorly understood. Our study shows that senescent fibroblasts displayed CAF properties, including the highly expressed CAF markers, α-SMA and Vimentin, and CAF-specific factors, CXCL12, FGF10, IL6 and COL1A1, which significantly increased collagen contractile activity and promoted the migration and invasion of lung cancer cells, H1299 and A549. We were further able to show that CAF characteristics in senescent fibroblasts could be regulated by the Stat3 pathway. Intracellular ROS accumulation activates the Stat3 pathway during senescence. Thus, our findings indicate that senescent fibroblasts mediate a CAF function with the Stat3 pathway. We further propose a novel Stat3 dependent targetable mechanism, which is instrumental in mediating the migration and invasion of lung cancer cells.
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Fibroblastos Associados a Câncer , Neoplasias Pulmonares , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Fibroblastos/metabolismo , Humanos , Interleucina-6/genética , Neoplasias Pulmonares/patologia , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Vimentina/metabolismoRESUMO
Soil moisture (SM) is an important parameter in land surface processes and the global water cycle. Remote sensing technologies are widely used to produce global-scale SM products (e.g., European Space Agency's Climate Change Initiative (ESA CCI)). However, the current spatial resolutions of such products are low (e.g., >3 km). In recent years, using auxiliary data to downscale the spatial resolutions of SM products has been a hot research topic in the remote sensing research area. A new method, which spatially downscalesan SM product to generate a daily SM dataset at a 16 m spatial resolution based on a spatiotemporal fusion model (STFM) and modified perpendicular drought index (MPDI), was proposed in this paper. (1) First, a daily surface reflectance dataset with a 16 m spatial resolution was produced based on an STFM. (2) Then, a spatial scale conversion factor (SSCF) dataset was obtained by an MPDI dataset, which was calculated based on the dataset fused in the first step. (3) Third, a downscaled daily SM product with a 16 m spatial resolution was generated by combining the SSCF dataset and the original SM product. Five cities in southern Hebei Province were selected as study areas. Two 16 m GF6 images and nine 500 m MOD09GA images were used as auxiliary data to downscale a timeseries 25 km CCI SM dataset for nine dates from May to June 2019. A total of 151 in situ SM observations collected on 1 May, 21 May, 1 June, and 11 June were used for verification. The results indicated that the downscaled SM data with a 16 m spatial resolution had higher correlation coefficients and lower RMSE values compared with the original CCI SM data. The correlation coefficients between the downscaled SM data and in situ data ranged from 0.45 to 0.67 versus 0.33 to 0.54 for the original CCI SM data; the RMSE values ranged from 0.023 to 0.031 cm3/cm3 versus 0.027 to 0.032 cm3/cm3 for the original CCI SM data. The findings described in this paper can ensure effective farmland management and other practical production applications.
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Secas , Solo , Mudança Climática , Monitoramento Ambiental/métodos , Tecnologia de Sensoriamento Remoto/métodosRESUMO
Aiming at the on-orbit safety problem of the two-dimensional tracking servo system for space, based on ant colony optimization (ACO) and expert systems, this paper proposes a fault diagnosis and handling strategy of the two-dimensional (2D) tracking servo system for space. Specifically, a fault library was established for the tracking servo system according to field observations. The ACO was called to optimize the classification of fault features. In addition, sensitivity and specificity were defined to evaluate the classification performance of the diagnosis rules found by the ant colony, aiming to suppress the redundant information in fault diagnosis, reduce the rows of the in-orbit codes, and improve the accuracy of in-orbit fault diagnosis. Meanwhile, the diagnosis information will be processed by the expert system, such that the servo system can work safely and stably in orbit, and less number of in-orbit computing resources were used. Simulation results show that the proposed strategy achieves highly precise and reliable diagnosis.
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Simulação por ComputadorRESUMO
MiRNA-size small RNAs, abbreviated as sRNAs, are increasingly being discovered as research progresses and omics technologies development in prokaryotes. However, there is a paucity of data concerning whether or not sRNAs exist in cyanobacteria and regulate the resistance to oxidative stress. In this investigation, small RNA libraries were constructed from the control, 50-nM and 100-nM H2O2 treatments of Spirulina platensis. By high-throughput sequencing, 23 candidate sRNAs showed significantly differential expression under oxidative stress, among which eight sRNAs were identified with the similar expression patterns as the sequencing results by real-time qPCR. By nucleic acid hybridisation, the corresponding expression changes also demonstrated that sequencing results of sRNAs were feasible and credible. By bioinformatics prediction and structure identification, 43 target genes were predicted for 8 sRNAs in plant miRNA database, among which 29 were annotated into the genome and related metabolic pathways of S. platensis. By COG functional classification and KEGG pathway analysis, 31 target genes were predicted to be directly or indirectly involved in the defence mechanism of H2O2 stress. Thirteen target genes displayed reversely changing patterns compared with those of their sRNAs under H2O2 treatment. These findings provide compelling evidence that these sRNAs in S. platensis play a crucial role in oxidative stress responses, and thus provide a theoretical reference for improving the stress-triggering physiological regulation.
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MicroRNAs , Spirulina , Antioxidantes , Sequenciamento de Nucleotídeos em Larga Escala , Peróxido de HidrogênioRESUMO
We report the spatiotemporal mode-locked multimode fiber laser operating at 1.55â µm based on semiconductor saturable absorber mirrors with the mode-locking threshold as low as 104â mW. Benefiting from the multimode interference filtering effect introduced in the laser cavity not only the central wavelength can be continuously tuned from 1557â nm to 1567â nm, but also the number of the output pulses can be adjusted from 1 to 4 by simply adjusting the polarization controllers. This work provides a new platform for exploring the dynamic characteristics of spatiotemporal mode-locked pulses at negative dispersion regime. Moreover, this kind of tunable laser has potential applications in fields of all-optical signal processing, fiber sensing and information coding.
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We propose an optical fiber sensor for low refractive index (RI) based on a serial-tilted-tapered fiber (STTF), which can be considered as two tightly concatenated micro Mach-Zehnder interferometers (MZIs). The STTF has a compact length of 959.8 µm, and can realize point detection and sensing in limited space. Numerical simulations reveal that a significantly strong evanescent field occurs around the STTF, making it to have the high sensitivity for surrounding RI. In the experiments, the interference dips show the nonlinear wavelength and intensity responses with increasing RI from 1.3395 to 1.3538. In the RI range of 1.3532~1.3538, the RI sensitivities reach the highest value of 2300 nm/RIU and -16183.33 dB/RIU. Moreover, the transmission spectrum of the STTF is low sensitive to temperature. These results indicate that our proposed sensor can be an appropriate candidate in most chemical and biological applications.
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In this paper, we developed an auto-focus image quality evaluation function from the histogram feature function (HFF) of a high-speed camera. Based on this function, we then proposed a fast auto-focus search algorithm. We further demonstrated that the auto-focus image quality evaluation function we proposed requires fewer computational resources, while providing a more effective focusing area and more moderate sensitivity, compared to the traditional evaluation function. In contrast to the traditional climbing method, our proposed fast auto-focusing search algorithm also can spot the focus point in a shorter time, effectively reducing the round trips of the focusing motor and improving the focusing accuracy.
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Dicer1 is an enzyme essential for microRNA (miRNA) maturation. The loss of miRNAs resulted from Dicer1 deficiency greatly contributes to the progression of many diseases, including lipid dysregulation, but its role in hepatic accumulation of free cholesterol (FC) that is critical in the development of non-alcoholic steatohepatitis (NASH) remains elusive. In this study, we used the liver-specific Dicer1-knockout mice to identify the miRNAs involved in hepatic FC accumulation. In a widely used dietary NASH model, mice were fed a methionine-choline-deficient (MCD) diet for 3 weeks, which resulted in significant increase in hepatic FC levels as well as decrease of Dicer1 mRNA levels in livers. The liver-specific Dicer1-knockout induced hepatic FC accumulation at 5-6 weeks, accompanied by increased mRNA and protein levels of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), a rate-limiting enzyme of cholesterol synthesis in livers. Eleven predicted miRNAs were screened, revealing that miR-29a/b/c significantly suppressed HMGCR expression by targeting the HMGCR mRNA 3'-UTR. Overexpression of miR-29a in SMMC-7721 cells, a steatosis hepatic cell model, significantly decreased HMGCR expression and the FC level. Furthermore, the expression levels of miR-29a were inversely correlated with HMGCR expression levels in the MCD diet mouse model in vivo and in 2 steatosis hepatic cell models (SMMC-7721 and HL-7702 cells) in vitro. Our results show that Dicer1/miR-29/HMGCR axis contributes to hepatic free cholesterol accumulation in mouse NASH, and miR-29 may serve as an important regulator of hepatic cholesterol homeostasis. Thus, miR-29a could be utilized as a potential therapeutic target for the treatment of non-alcoholic fatty liver disease as well as for other liver diseases associated with FC accumulation.
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Colesterol/metabolismo , RNA Helicases DEAD-box/deficiência , Hidroximetilglutaril-CoA Redutases/metabolismo , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Ribonuclease III/deficiência , Animais , RNA Helicases DEAD-box/metabolismo , Dieta/efeitos adversos , Técnicas de Inativação de Genes , Masculino , Metionina/deficiência , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , RNA Mensageiro/metabolismo , Ribonuclease III/metabolismoRESUMO
Previous studies have shown that microRNA-1304 (miR-1304) is dysregulated in certain types of cancers, including non-small cell lung cancer (NSCLC), and might be involved in tumor survival and/or growth. In this study we investigated the direct target of miR-1304 and its function in NSCLC in vitro. Human lung adenocarcinoma cell lines (A549 and NCI-H1975) were studied. The cell proliferation and survival were investigated via cell counting, MTT and colony-formation assays. Cell apoptosis and cell cycle were examined using annexin V-PE/7-AAD and PI staining assays, respectively. The dual-luciferase reporter assay was used to verify post-transcriptional regulation of heme oxygenase-1 (HO-1) by miR-1304. CRISPR/Cas9 was used to deplete endogenous miR-1304. Overexpression of MiR-1304 significantly decreased the number and viability of NSCLC cells and colony formation, and induced cell apoptosis and G0/G1 phase cell cycle arrest. HO-1 was demonstrated to be a direct target of miR-1304 in NSCLC cells. Restoration of HO-1 expression by hemin (20 µmol/L) abolished the inhibition of miR-1304 on cell growth and rescued miR-1304-induced apoptosis in A549 cells. Suppression of endogenous miR-1304 with anti-1304 significantly increased HO-1 expression and promoted cell growth and survival in A549 cells. In 17 human NSCLC tissue samples, miR-1304 expression was significantly decreased, while HO-1 expression was significantly increased as compared to normal lung tissues. MicroRNA-1304 is a tumor suppressor and HO-1 is its direct target in NSCLC. The results suggest the potential for miR-1304 as a therapeutic target for NSCLC.
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Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/antagonistas & inibidores , MicroRNAs/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Heme Oxigenase-1/metabolismo , Hemina/farmacologia , Humanos , MicroRNAs/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Ensaio Tumoral de Célula-Tronco , Regulação para CimaRESUMO
The invention of DNA cloning over 40 years ago marked the advent of molecular biology. The technique has now become a routine practice in any modern biomedical laboratory. Although positive-selection of recombinants in DNA cloning seems to be superior to blue/white selection based on the disruption of the lacZ gene, it is rarely practiced due to its high background, lack of multiple cloning sites, and inability to express the genes of interest or purify the protein products. Here we report the creation of a new positive-selection cloning vector dubbed pKILLIN, which overcomes all of the above pitfalls. The essence behind its high cloning efficiency is the extreme toxicity and small size of the toxic domain of killin, a recently discovered p53 target gene. Insertion inactivation of killin within the multiple cloning site via either blunt- or sticky-end ligation not only serves as a highly efficient cloning trap, but also may allow any cloned genes to be expressed as His-tagged fusion proteins for subsequent purification. Thus, pKILLIN is a versatile positive-selection vector ideal for cloning PCR products, making DNA libraries, as well as routine cloning and bacterial expression of genes.
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Clonagem Molecular/métodos , Escherichia coli/genética , Vetores Genéticos/genética , Proteínas Supressoras de Tumor/genética , Primers do DNA/genética , Óperon Lac/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/genéticaRESUMO
OBJECTIVE: To compare changes of blood clotting state after initial trauma fractures and twice trauma fractures, investigate the effect of fracture history to the state of the blood clotting after secondary trauma fractures. METHODS: Thirty New Zealand rabbits were selected, aged 5-6 months, males and females unlimited, weighted 2.4-2.6 kg, non-pregnant. Postoperative model of initial trauma fractures was established, and then postoperative model after twice trauma fractures was built. Prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fiber fibrinogen (FIB) and D-dimer (DD) were detected by venous blood at 1 day and 5 days after surgery. Changes of indicators were compared between after twice fractures at the same time. RESULTS: Comparing with 1 day after the secondary trauma fracture and initial trauma fracture surgery, PT, APTT values showed no significant difference (P > 0.05), TT, FIB, DD values were increased, and the difference was statistically significant (P < 0.05); Comparing with 5 days after the secondary trauma fracture and initial trauma fracture surgery, PT values showed no significant difference (P < 0 .05), APTT, TT, FIB, DD values were increased, and the difference was statistically significant (P< 0.05). CONCLUSION: Blood after the secondary trauma fractures is in hypercoagulable state after fracture surgery.