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1.
Chin Med J (Engl) ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38403900

RESUMEN

BACKGROUND: Clinical opportunistic screening is a cost-effective cancer screening modality. This study aimed to establish an easy-to-use diagnostic model serving as a risk stratification tool for identification of individuals with malignant gastric lesions for opportunistic screening. METHODS: We developed a questionnaire-based diagnostic model using a joint dataset including two clinical cohorts from northern and southern China. The cohorts consisted of 17,360 outpatients who had undergone upper gastrointestinal endoscopic examination in endoscopic clinics. The final model was derived based on unconditional logistic regression, and predictors were selected according to the Akaike information criterion. External validation was carried out with 32,614 participants from a community-based randomized controlled trial. RESULTS: This questionnaire-based diagnostic model for malignant gastric lesions had eight predictors, including advanced age, male gender, family history of gastric cancer, low body mass index, unexplained weight loss, consumption of leftover food, consumption of preserved food, and epigastric pain. This model showed high discriminative power in the development set with an area under the receiver operating characteristic curve (AUC) of 0.791 (95% confidence interval [CI]: 0.750-0.831). External validation of the model in the general population generated an AUC of 0.696 (95% CI: 0.570-0.822). This model showed an ideal ability for enriching prevalent malignant gastric lesions when applied to various scenarios. CONCLUSION: This easy-to-use questionnaire-based model for diagnosis of prevalent malignant gastric lesions may serve as an effective prescreening tool in clinical opportunistic screening for gastric cancer.

2.
BMC Biotechnol ; 24(1): 2, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200466

RESUMEN

BACKGROUND: Lytic polysaccharide monooxygenases (LPMOs) catalyzing the oxidative cleavage of different types of polysaccharides have potential to be used in various industries. However, AA13 family LPMOs which specifically catalyze starch substrates have relatively less members than AA9 and AA10 families to limit their application range. Amylase has been used in enzymatic desizing treatment of cotton fabric for semicentury which urgently need for new assistant enzymes to improve reaction efficiency and reduce cost so as to promote their application in the textile industry. RESULTS: A total of 380 unannotated new genes which probably encode AA13 family LPMOs were discovered by the Hidden Markov model scanning in this study. Ten of them have been successfully heterologous overexpressed. AlLPMO13 with the highest activity has been purified and determined its optimum pH and temperature as pH 5.0 and 50 °C. It also showed various oxidative activities on different substrates (modified corn starch > amylose > amylopectin > corn starch). The results of enzymatic textile desizing application showed that the best combination of amylase (5 g/L), AlLPMO13 (5 mg/L), and H2O2 (3 g/L) made the desizing level and the capillary effects increased by 3 grades and more than 20%, respectively, compared with the results treated by only amylase. CONCLUSION: The Hidden Markov model constructed basing on 34 AA13 family LPMOs was proved to be a valid bioinformatics tool for discovering novel starch-active LPMOs. The novel enzyme AlLPMO13 has strong development potential in the enzymatic textile industry both concerning on economy and on application effect.


Asunto(s)
Peróxido de Hidrógeno , Almidón , Humanos , Polisacáridos , Amilasas , Biología Computacional , Oxigenasas de Función Mixta/genética , Textiles
3.
BMC Emerg Med ; 23(1): 146, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38104084

RESUMEN

BACKGROUND: Implementing training programs to educate patients on the prodromal symptoms of acute coronary syndrome (ACS) may assist patients in accurately recognizing these symptoms, and ultimately decrease their time delay in seeking emergency medical services (EMS). However, the effectiveness of this approach remains uncertain, particularly among the Chinese population. METHODS: A cross-sectional study was conducted within 22 communities in Beijing, China between 2015 and 2018, with a total of 1099 participants recruited. The study utilized a standardized questionnaire to evaluate the presence of intentional decision delay in turning to EMS under a hypothetical chest pain, the participants' knowledge of ACS prodromal symptoms, and whether they had ever received any training programs aimed at increasing their symptom knowledge. Mediation analysis was performed with regression models and bootstrapping methods, and gender difference was further analyzed through moderated mediation analysis. RESULTS: A total of 1099 participants (58.2% female, median [IQR] age 34 [20]) were included in the study. The results of the mediation analysis indicated that training programs were associated with a decrease risk in decision delay, with increased knowledge playing a mediating role (mediation effect/total effect = 36.59%, P < 0.0001). Gender modified this mediation effect, with it being observed only in the male group. Specifically, training programs were not found to significantly decrease decision delay among females (P > 0.05), even though they did improve women's knowledge of ACS prodromal symptoms (ß = 0.57, P = 0.012). CONCLUSION: The results suggested a relationship between prior training programs and reduced decision delay, with increased knowledge of prodromal symptoms of ACS serving as a mediator. However, the effect was only observed in male participants and not in female participants. This highlights the notion that mere transfer of knowledge regarding ACS prodromal symptoms may not be sufficient to mitigate decision delay in the female population. Further research is needed to corroborate these results and to gain deeper insights into the gender-specific barriers encountered in this study.


Asunto(s)
Síndrome Coronario Agudo , Servicios Médicos de Urgencia , Humanos , Masculino , Femenino , Adulto , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Estudios Transversales , Síntomas Prodrómicos , China
4.
Bioengineering (Basel) ; 10(8)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37627862

RESUMEN

At present, the double-enzyme catalyzed method using maltooligosyltrehalose synthase (MTSase) and maltooligosyltrehalose trehalohydrolase (MTHase) is the mainstream technology for industrial trehalose production. However, MTSase and MTHase are prepared mainly using the heterologous expression in the engineered Escherichia coli strains so far. In this study, we first proved that the addition of 3 U/g neutral pullulanase PulA could enhance the trehalose conversion rate by 2.46 times in the double-enzyme catalyzed system. Then, a CBM68 domain was used to successfully assist the secretory expression of MTSase and MTHase from Arthrobacter ramosus S34 in Bacillus subtilis SCK6. At the basis, an engineered strain B. subtilis PSH02 (amyE::pulA/pHT43-C68-ARS/pMC68-ARH), which co-expressed MTSase, MTHase, and PulA, was constructed. After the 24 h fermentation of B. subtilis PSH02, the optimum ratio of the extracellular multi-enzymes was obtained to make the highest trehalose conversion rate of 80% from 100 g/L maltodextrin. The high passage stability and multi-enzyme preservation stability made B. subtilis PSH02 an excellent industrial production strain. Moreover, trehalose production using these extracellular enzymes produced via the one-step fermentation of B. subtilis PSH02 would greatly simplify the procedure for multi-enzyme preparation and be expected to reduce production costs.

5.
Cell Rep Med ; 4(9): 101168, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37625408

RESUMEN

The genomic characteristics during the carcinogenic process of esophageal squamous cell carcinoma (ESCC) remain largely unknown. We report here the genomic characteristics of 106 esophageal tissues of various stages from a population-based screening cohort in China ("Endoscopic Screening for Esophageal Cancer in China" trial) and 57 ESCC tissues from a local hospital. A significant increase in somatic mutation and copy number alterations is observed in the non-dysplastic Lugol unstaining lesions (ND-LULs). Extensive clonal expansion has emerged in the ND-LULs to an extent similar to that in higher-stage lesions. The burden of genomic alterations correlates with the size of LULs in the ND-LULs. 8-year follow-up shows that ND-LULs harbor an increased risk of progression to ESCC (adjusted IRR6-10 mm vs. none = 4.66, adjusted IRR>10 mm vs. none = 40.70), and the risk is correlated with LUL size for both non-dysplastic and dysplastic lesions. Lugol unstaining can be the initial stage in the carcinogenic process of ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/epidemiología , Carcinoma de Células Escamosas de Esófago/genética , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/genética , Genómica , Estudios Epidemiológicos , Carcinógenos , Coloración y Etiquetado
6.
Front Public Health ; 11: 1189993, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37521988

RESUMEN

Background: We initiated the Fujian Tulou Pedigree-based Cohort (FTPC) as the integration of extended pedigrees and prospective cohort to clarify the genetic and environmental risk factors of cardiometabolic diseases. Methods: FTPC was carried out in Nanjing County, Fujian Province, China from August 2015 to December 2017 to recruit probands with the same surnames and then enroll their first-degree and more distant relatives. The participants were asked to complete questionnaire interview, physical examination, and blood collection. According to the local genealogical booklets and family registry, we reconstructed extended pedigrees to estimate the heritability of cardiometabolic traits. The follow-up of FTPC is scheduled every 5 years in the future. Results: The baseline survey interviewed 2,727 individuals in two clans. A total of 1,563 adult subjects who completed all baseline examinations were used to reconstruct pedigrees and 452 extended pedigrees were finally identified, including one seven-generation pedigree, two five-generation pedigrees, 23 four-generation pedigrees, 186 three-generation pedigrees, and 240 two-generation pedigrees. The average age of the participants was 57.4 years, with 43.6% being males. The prevalence of hypertension, diabetes and dyslipidemia in FTPC were 49.2, 10.0, and 45.2%, respectively. Based on the pedigree structure, the heritability of systolic blood pressure, diastolic blood pressure, fast blood glucose, total cholesterol, triglyceride, high-density lipoprotein, and low-density lipoprotein was estimated at 0.379, 0.306, 0.386, 0.452, 0.568, 0.852, and 0.387, respectively. Conclusion: As an extended pedigree cohort in China, FTPC will provide an important source to study both genetic and environmental risk factors prospectively.


Asunto(s)
Diabetes Mellitus , Hipertensión , Masculino , Adulto , Humanos , Persona de Mediana Edad , Femenino , Estudios Prospectivos , Linaje , Factores de Riesgo
7.
Front Bioeng Biotechnol ; 11: 1131875, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36777253

RESUMEN

Pullulan has many potential applications in the food, pharmaceutical, cosmetic and environmental industries. However, the yield and molecular properties of pullulan produced by various strains still need to be promoted to fit the application needs. A novel yeast-like strain Aureobasidium pullulans BL06 producing high molecular weight (Mw) pullulan (3.3 × 106 Da) was isolated and identified in this study. The remarkable Mw of pullulan produced by A. pullulans BL06 was the highest level ever reported thus far. To further regulate the biosynthesis of pullulan in A. pullulans BL06, three gene knockout strains A. pullulans BL06 ΔPMAs, A. pullulans BL06 Δmel, and A. pullulans BL06 ΔPMAsΔmel, were constructed. The results showed that A. pullulans BL06 ΔPMAs could produce 140.2 g/L of moderate Mw (1.3 × 105 Da) pullulan after 120 h of fermentation. The highest yield level of pullulan to date could vastly reduce its production cost and expand its application scope and potential. The application experiments in food preservation showed that the moderate-Mw pullulan obtained in this work could reduce the weight loss of celery cabbages and mangos by 12.5% and 22%, respectively. Thus, the novel strains A. pullulans BL06 and A. pullulans BL06 ΔPMAs possessed unlimited development prospects in pullulan production at various Mw ranges and pullulan applications in multiple fields.

8.
Oral Dis ; 29(3): 1080-1088, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34739175

RESUMEN

The folate-mediated one-carbon metabolism pathway is thought to play an important role in the etiology of non-syndromic oral clefts (NSOFC), although none of the genes in this pathway has shown significant signals in genome-wide association studies (GWAS). Recent evidence indicated that enhanced understanding could be gained by aggregating multiple SNPs effect simultaneously into polygenic risk score (PRS) to assess its association with disease risks. This study is aimed to assess the association between the genetic effect of folate-mediated one-carbon metabolism pathway and NSOFC risks using PRS based on a case-parent trio design. A total of 297 SNPs mapped from 18 genes in the folate-mediated one-carbon metabolism pathway were aggregated from a GWAS of 2458 case-parent trios recruited from an international consortium. We found a PRS based on the folate-mediated one-carbon metabolism pathway was significant among all NSOFC trios (OR = 1.95, 95% CI: 1.66-2.28, p = 2.39 × 10-16 ), as well as two major subtypes, non-syndromic cleft lip with or without cleft palate (NSCL/P) trios (OR = 1.71, 95% CI: 1.50-1.96, p = 7.66 × 10-15 ) and non-syndromic cleft palate only (NSCPO) trios (OR = 1.51, 95% CI: 1.36-1.68, p = 2.1 × 10-14 ). Similar results were also observed in further subgroup analyses stratified into Asian and European trios. The averaged PRS of the folate-mediated one-carbon metabolism pathway varied between the NSOFC case group and its comparison group (p < 0.05) with higher average PRS in the cases. Moreover, the top 5% pathway PRS group had 2.25 (95% CI: 1.85-2.73) times increased NSOFC risk, also 3.09 (95% CI: 2.50-3.81) and 2.06 (95% CI: 1.39-3.02) times increased risk of NSCL/P and NSCPO compared to the remainder of the distribution. The results of our study confirmed the folate-mediated one-carbon metabolism pathway was important in controlling risk to NSOFC and this study enhanced evidence towards understanding the genetic risks of NSOFC.


Asunto(s)
Labio Leporino , Fisura del Paladar , Humanos , Fisura del Paladar/genética , Estudio de Asociación del Genoma Completo , Ácido Fólico , Labio Leporino/genética , Carbono , Polimorfismo de Nucleótido Simple , Predisposición Genética a la Enfermedad/genética
9.
Cancers (Basel) ; 14(23)2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36497427

RESUMEN

We aimed to develop an improved version of the diagnostic model predicting the risk of malignant esophageal lesions in opportunistic screening and validate it in external populations. The development set involved 10,595 outpatients receiving endoscopy from a hospital in Hua County, a high-risk region for esophageal squamous cell carcinoma in northern China. Validation set A enrolled 9453 outpatients receiving endoscopy in a non-high-risk region in southern China. Validation set B involved 17,511 residents in Hua County. The improved diagnostic model consisted of seven predictors including age, gender, family history of esophageal squamous cell carcinoma, smoking, body mass index, dysphagia, and retrosternal pain, with an area under the receiver operating characteristic curve (AUC) of 0.860 (95% confidence interval: 0.835-0.886) in the development set. Ideal discrimination ability was achieved in external validations (AUC validation set A: 0.892, 95% confidence interval: 0.858-0.926; AUC validation set B: 0.799, 95% confidence interval: 0.705-0.894). This improved model also markedly increased the detection rate of malignant esophageal lesions compared with universal screening, demonstrating great potential for use in opportunistic screening of malignant esophageal lesions in heterogeneous populations.

10.
EClinicalMedicine ; 47: 101394, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35480078

RESUMEN

Background: Previous risk prediction models taking esophageal malignant lesions detected during endoscopy as the primary outcome are not always sufficient to identify prevalent cases which are "overlooked" at screening. We aimed to update and externally validate our previous risk prediction model for malignant esophageal lesions by redefining the predicted outcome. Methods: 15,192 individuals from the Endoscopic Screening for Esophageal Cancer in China randomized controlled trial (ESECC trial, NCT01688908) were included as the training set, and 4576 participants from another population-based esophageal squamous cell carcinoma (ESCC) screening cohort (Anyang Esophageal Cancer Cohort Study, AECCS) served as the external validation set. Lesions with severe dysplasia or worse diagnosed at chromoendoscopy or identified via follow-up within 1 year after screening were defined as main outcome. Logistic regressions were applied to reconstruct the questionnaire-based prediction model using information collected before screening, with Akaike Information Criterion to determine the model structure. Findings: The final prediction model included age and its quadratic term, family history of ESCC, low body mass index (≤22 kg/m2), use of coal or wood as main fuel for cooking, eating rapidly, and ingestion of leftover food. The area under the curve was 0·77 (95% CI: 0·73-0·80) and 0·71 (95% CI: 0·65-0·78) in the training and validation set. When screening the top 50% or 10% of high-risk individuals within population, the detection rates can be increased in both cohorts, as compared to universal screening. Interpretation: The described tool may promote the efficiency of current national screening programs for ESCC and contribute to a precision screening strategy in high-risk regions in China. Funding: This work was supported by the National Natural Science Foundation of China (82073626, 81773501), the National Science & Technology Fundamental Resources Investigation Program of China (2019FY101102), the National Key R&D Program of China (2021YFC2500405), the Beijing-Tianjin-Hebei Basic Research Cooperation Project (J200016), the Digestive Medical Coordinated Development Center of Beijing Hospitals Authority (XXZ0204) and the Beijing Nova Program (Z201100006820093). Sponsors had no role in the study design, data collection, analysis, and interpretation of data.

11.
Int J Biol Macromol ; 203: 58-66, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35092735

RESUMEN

A novel Escherichia coli efficient expression system had been constructed in our previous study. The system was based on the overexpression of endogenous genes prpD and malK to enhance the expression of exogenous genes. In this study, a general regulatory mechanism of prpD and malK was first revealed through transcriptome analysis and many experimental verifications. We surprisingly proved that overexpression of malK could up-regulate the expression of prpD and propanoate metabolism, which leads to increased expression of exogenous genes. More importantly, the overexpression of prpD or malK could arouse a complex set of pyruvate-centered metabolic networks that mainly increase the energy supply (ATP), by-product recycling (acetate), and amino acids for the efficient expression of exogenous genes. This novel theory for promoting the efficient expression of exogenous genes will be useful in a wide range of fields. It also opens up a new perspective on the regulation of metabolism in E. coli cells.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Ácido Pirúvico/metabolismo
12.
Sheng Wu Gong Cheng Xue Bao ; 38(11): 4219-4239, 2022 Nov 25.
Artículo en Chino | MEDLINE | ID: mdl-37699687

RESUMEN

The green bio-manufacturing industry, characterized with high efficiency, safety, energy-saving, and environmental-friendliness, is a national strategic emerging industry with broad market prospect. Industrial enzyme is the "chip" of green biological process. The exploitation and application of new industrial enzymes is one of the core enabling technologies of green bio-manufacturing. This review introduces the current situation of industrial enzyme industry, followed by summarizing a series of key technical breakthroughs and research progress in industrial enzymes as well as green biological technologies and processes, which were developed by Tianjin institute of industrial biotechnology, Chinese Academy of Sciences in the past 10 years. Typical cases where traditional processing industry was promoted by the development and application of enzyme and green biological technologies were also presented. It is envisioned that development of these core technologies will enable more traditional processing industries transform into green and sustainable bio-based industry.


Asunto(s)
Biotecnología , Industrias
13.
Br J Clin Pharmacol ; 88(2): 500-513, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34322914

RESUMEN

AIMS: The results of associations between new oral anticoagulants (NOACs) and wound complications after total joint arthroplasty remain inconsistent. We conducted a systematic review and meta-analysis of randomized controlled trials to make comparisons with low molecular weight heparins (LMWH) on the clinical outcomes of total wound complications, together with other efficacy and safety endpoints to further evaluate the safety and efficacy of NOACs. METHODS: This meta-analysis was conducted based on a published protocol (PROSPERO: CRD42019140841). We searched for available articles in PubMed, Embase and Cochrane Library through Jun 62 021. Random-effects meta-analyses, including subgroup analyses, were conducted to estimate the pooled relative risk (RR) and 95% confidence interval (CI) for specific doses of NOACs. RESULTS: We retrieved 1683 studies, of which 20 were eligible for inclusion. We found that apixaban was associated with a lower incidence of total wound complications compared with LMWH (RR = 0.81; 95% CI: 0.65-1.00), while dabigatran and rivaroxaban did not increase the risk of total wound complications. In addition, apixaban was associated with a reduction in the risk of major/clinically relevant nonmajor bleeding events compared to LMWH (RR = 0.80, 95% CI: 0.65-0.99), while rivaroxaban increased the risk for major/clinically relevant nonmajor bleeding events (RR = 1.23, 95% CI: 1.02-1.50). Moreover, all 4 NOACs were associated with lower incidences of major venous thromboembolism compared with LMWH. CONCLUSION: A lower risk of wound complications was detected for apixaban, while dabigatran and rivaroxaban did not increase the risk when compared with LMWH. The efficacy of 4 NOACs was broadly similar.


Asunto(s)
Anticoagulantes , Tromboembolia Venosa , Administración Oral , Anticoagulantes/efectos adversos , Artroplastia/efectos adversos , Dabigatrán/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/complicaciones , Hemorragia/epidemiología , Heparina de Bajo-Peso-Molecular/efectos adversos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Rivaroxabán/efectos adversos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control
14.
Int J Biol Macromol ; 193(Pt A): 238-246, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34710472

RESUMEN

Bacillus subtilis has been widely used as a prokaryotic host for the secretory expression of heterologous proteins. In this study, a pullulanase (PulA) from Anoxybacillus sp. LM18-11 was firstly identified to be expressed in Bacillus subtilis 1A751 through non-classical secretion pathway. Results showed that both the N- and C-terminal regions of PulA were essential for its soluble expression. To explore its specific structural basis of secretion in B. subtilis, we revealed a hydrophobic motif A501-H507 which is vital for the secretion of the whole protein of PulA. Through a series of site-specific mutagenesis, the triple-sites mutants R503E/I506E/H507E and R503E/I506Y/H507E showed the highest extracellular activity (160.07 U/mL) and total activity (243.37 U/mL) which was 1.71 times and 1.55 times higher than those of PulA. The highest secretion rate of mutant I506E/H507E was more than 50% which was 34.72% higher comparing with that of PulA. The glutamic acid substitution on these three key surface sites which decreased the surface hydrophobicity of that region was confirmed to be beneficial to improve the secretory expression of PulA. This novel discovery for the secretory expression of PulA in B. subtilis would make a new perspective on regulating a kind of non-classical secretion in B. subtilis.


Asunto(s)
Bacillus subtilis/enzimología , Proteínas Bacterianas , Glicósido Hidrolasas , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Glicósido Hidrolasas/química , Glicósido Hidrolasas/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Dominios Proteicos
15.
Chin J Cancer Res ; 33(6): 649-658, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35125809

RESUMEN

OBJECTIVE: This study aimed to develop and validate a risk scoring system to identify high-risk individuals carrying malignant lesions in stomach for tailored gastric cancer screening. METHODS: A gastric cancer risk scoring system (GC-RSS) was developed based on questionnaire-based predictors for gastric cancer derived from systematic literature review. To assess the capability of this system for discrimination, risk scores for 8,214 and 7,235 outpatient subjects accepting endoscopic examination in two endoscopy centers, and 32,630 participants in a community-based cohort in China were calculated to plot receiver operating characteristic curves and generate area under the curve (AUC). To evaluate the performance of GC-RSS, the screening proportion, sensitivity and detection rate ratio compared to universal screening were used under different risk score cutoff values. RESULTS: GC-RSS comprised nine predictors including advanced age, male gender, low body mass index (<18.5 kg/m2), family history of gastric cancer, cigarette smoking, consumption of alcohol, preference for salty food, irregularity of meals and consumption of preserved food. This tool performed well in determining the risk of malignant gastric lesions with AUCs of 0.763, 0.706 and 0.696 in three validation sets. When subjects with risk scores ≥5 were evaluated with endoscopy, nearly 50% of these endoscopies could be saved with a detection rate of over 1.5 times achieved. When the cutoff was set at 8, only about 10% of subjects with the highest risk would be offered endoscopy, and detection rates for gastric cancer could be increased 2-4 fold compared to universal screening. CONCLUSIONS: An effective questionnaire-based GC-RSS was developed and validated. This tool may play an important role in establishing a tailored screening strategy for gastric cancer in China.

16.
Int J Biol Macromol ; 165(Pt A): 609-618, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33010275

RESUMEN

A wild strain Bacillus amyloliquefaciens 205 was screened for its high activity of α-amylase. A mesophilic α-amylase encoding gene amyE-205 was revealed and analyzed by genome sequencing. In order to facilitate plasmid transformation to strain 205, an interspecific plasmid transformation method was improved with 5-13 times higher in transformants than that of electronic transformation. A series of CRISPR genome editing tools have been successfully constructed for gene knockout, transcript repression and activation in 205 genome. At this basis, sporulation related genes spo0A and spoIIAC were knockout and suppressed with CRISPR/Cas9 and CRISPR/dCas9 respectively. The double knockout strain 205spo- was eliminated sporulation with 22.8% increasing of α-amylase activity. The optimal binding site G8 for dCas9-ω has been confirmed in the transcript activation. When amyE-205 was over-expressed with high copy plasmid pUC980-2, its whole upstream sequences containing G8 were also cloned. Whereafter, dCas9-ω was used to activate amyE-205 expression both at genome and plasmid. The final engineered strain 205PG8spo- achieved 784.3% promotion on α-amylase activity than the starting strain 205. The novel genetic tool box containing an efficient interspecific transformation method and functional CRISPR systems, superadded the multiplex regulation strategies used in strain modification would be also applicative in many Bacillus species.


Asunto(s)
Bacillus amyloliquefaciens , Proteínas Bacterianas , Edición Génica , Regulación Bacteriana de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , alfa-Amilasas , Bacillus amyloliquefaciens/enzimología , Bacillus amyloliquefaciens/genética , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Sistemas CRISPR-Cas , alfa-Amilasas/biosíntesis , alfa-Amilasas/genética
17.
Int J Mol Sci ; 21(16)2020 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-32796599

RESUMEN

Steviol glycosides (SGs) with zero calories and high-intensity sweetness are the best substitutes of sugar for the human diet. Uridine diphosphate dependent glycosyltransferase (UGT) UGT76G1, as a key enzyme for the biosynthesis of SGs with a low heterologous expression level, hinders its application. In this study, a suitable fusion partner, Smt3, was found to enhance the soluble expression of UGT76G1 by 60%. Additionally, a novel strategy to improve the expression of Smt3-UGT76G1 was performed, which co-expressed endogenous genes prpD and malK in Escherichia coli. Notably, this is the first report of constructing an efficient E. coli expression system by regulating prpD and malK expression, which remarkably improved the expression of Smt3-UGT76G1 by 200% as a consequence. Using the high-expression strain E. coli BL21 (DE3) M/P-3-S32U produced 1.97 g/L of Smt3-UGT76G1 with a yield rate of 61.6 mg/L/h by fed-batch fermentation in a 10 L fermenter. The final yield of rebadioside A (Reb A) and rebadioside M (Reb M) reached 4.8 g/L and 1.8 g/L, respectively, when catalyzed by Smt3-UGT76G1 in the practical UDP-glucose regeneration transformation system in vitro. This study not only carried out low-cost biotransformation of SGs but also provided a novel strategy for improving expression of heterologous proteins in E. coli.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Glicósidos/biosíntesis , Glicosiltransferasas/metabolismo , Hidroliasas/metabolismo , Biocatálisis , Reactores Biológicos/microbiología , Biotransformación , Fermentación , Glicósidos/química , Glicosilación , Plásmidos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Recombinación Genética/genética , Solubilidad
18.
Artículo en Inglés | MEDLINE | ID: mdl-32325946

RESUMEN

Background: The association between smoking and blood pressure (BP) has been explored extensively, yet the results remain inconclusive. Using real-world evidence of a large Chinese population, we examine the effect of smoking on BP levels. Methods: We utilize half a million adults from the China Kadoorie Biobank (CKB) study with baseline sampling collected between 2004 and 2008. Multivariable linear regression analyses are used to estimate linear regression coefficients of smoking for systolic blood pressure (SBP) and diastolic blood pressure (DBP). Results: 459,815 participants (180,236 males and 279,579 females) are included in the analysis. Regular smoking is significantly associated with lower SBP (-0.57 mm Hg, p < 0.001) and DBP (-0.35 mm Hg, p < 0.001) when compared with non-smoking in men. Additionally, SBP and DBP decrease significantly among all groups of different smoking status in women (p < 0.001). Additionally, pack-years show negative associations with SBP and DBP in both men and women. Further analysis shows the interaction of smoking and alcohol consumption is associated with an increase of SBP and DBP (men: 2.38 mm Hg and 0.89 mm Hg; women: 5.21 mm Hg and 2.62 mm Hg) among co-regular smokers and regular drinkers when compared with regular smokers who are not exposed to alcohol consumption. Conclusions: A negative association between smoking and BP is observed. However, the interaction between smoking and alcohol consumption is associated with BP increase. The findings suggest the importance of considering smoking and alcohol consumption in BP control in addition to antihypertensive treatment in clinical and public health practice.


Asunto(s)
Presión Sanguínea , Fumar/efectos adversos , Adulto , Anciano , Pueblo Asiatico , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
3 Biotech ; 10(2): 49, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32002340

RESUMEN

A high heterologous expression of an alkaline pectate lyase (APL) pelNK93I in E. coli was obtained through optimizing the lactose feeding and fed-batch fermentation. The highest soluble APL activity produced by E. coli BL21 (pET22b-pelNK93I) was 10,181 U/mL which is the highest level so far. On this basis, to improve the extracellular yield of APL, optimized glycine feeding was used to achieve elevated extracellular production of pelNK93I. The highest extracellular APL activity produced by E. coli BL21 (pET22b-pelNK93I) was 6357 U/mL which was also relatively higher than that in previous reports. The final productivity of APL was 282.8 U/mL/h in the fermentation of E. coli BL21 (pET22b-pelNK93I) in a 10 L fermenter. Thus the current study has provided a cost-effective method for the over-expression and preparation of alkaline pectate lyase pelNK93I for its industrial applications. Moreover, pelNK93I (4 U/mL) used for bioscouring increased cottonseed husk removal and radial capillary effect of cotton fabric by 37.63% and 47.06%, respectively, making it a promising enzyme in green textile technology.

20.
Microb Cell Fact ; 19(1): 25, 2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32028973

RESUMEN

BACKGROUND: pWB980 derived from pUB110 is a promising expression vector in Bacillus for its high copy number and high stability. However, the low transformation rate of recombinant plasmids to the wild cells limited the application of it. On the basis of pWB980, constructing an E. coli-B. subtilis shuttle plasmid could facilitate the transformation rate to Bacillus cells. Because the insertion site for E. coli replication origin sequence (ori) is not unique in pWB980, in order to investigate the best insertion site, eight shuttle plasmids (pUC980-1 ~ pUC980-8) containing all possible insertion sites and directions were constructed. RESULTS: The results showed that all the selected insertion sites could be used to construct shuttle plasmid but some sites required a specific direction. And different insertion sites led to different properties of the shuttle plasmids. The best shuttle plasmids pUC980-1 and pUC980-2, which showed copies more than 450 per cell and segregational stabilities up to 98%, were selected for heterologous expressions of an alkaline pectate lyase gene pelN, an alkaline protease spro1 and a pullulanase gene pulA11, respectively. The highest extracellular activities of PelN, Spro1 and PulA11 were up to 5200 U/mL, 21,537 U/mL and 504 U/mL correspondingly after 54 h, 60 h and 48 h fermentation in a 10 L fermentor. Notably, PelN and Spro1 showed remarkably higher yields in Bacillus than previous reports. CONCLUSION: The optimum ori insertion site was the upstream region of BA3-1 in pWB980 which resulted in shuttle plasmids with higher copy numbers and higher stabilities. The novel shuttle plasmids pUC980-1 and pUC980-2 will be promising expression vectors in B. subtilis. Moreover, the ori insertion mechanism revealed in this work could provide theoretical guidance for further studies of pWB980 and constructions of other shuttle plasmids.


Asunto(s)
Bacillus subtilis/genética , Escherichia coli/genética , Vectores Genéticos/genética , Plásmidos/genética , Variaciones en el Número de Copia de ADN , Inestabilidad Genómica/genética
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