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1.
Front Bioeng Biotechnol ; 12: 1327172, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38532881

RESUMEN

Corynebacterium glutamicum plays a crucial role as a significant industrial producer of metabolites. Despite the successful development of CRISPR-Cas9 and CRISPR-Cas12a-assisted genome editing technologies in C. glutamicum, their editing resolution and efficiency are hampered by the diverse on-target activities of guide RNAs (gRNAs). To address this problem, a hybrid CRISPR-Cas9-Cas12a genome editing platform (HyCas9-12aGEP) was developed in C. glutamicum in this study to co-express sgRNA (corresponding to SpCas9 guide RNA), crRNA (corresponding to FnCas12a guide RNA), or hfgRNA (formed by the fusion of sgRNA and crRNA). HyCas9-12aGEP improves the efficiency of mapping active gRNAs and outperforms both CRISPR-Cas9 and CRISPR-Cas12a in genome editing resolution and efficiency. In the experiment involving the deletion of the cg0697-0740 gene segment, an unexpected phenotype was observed, and HyCas9-12aGEP efficiently identified the responsible genotype from more than 40 genes. Here, HyCas9-12aGEP greatly improve our capability in terms of genome reprogramming in C. glutamicum.

2.
Zhongguo Zhong Yao Za Zhi ; 48(22): 6075-6081, 2023 Nov.
Artículo en Chino | MEDLINE | ID: mdl-38114214

RESUMEN

With the continuous exploration of microemulsions as solvents for traditional Chinese medicine extraction, polyoxyethy-lene(35) castor oil(CrEL), a commonly used surfactant, is being utilized by researchers. However, the problem of detecting residues of this surfactant in microemulsion extracts has greatly hampered the further development of microemulsion solvents. Based on the chemical structures of the components in CrEL and the content determination method of castor oil in the 2020 edition of the Chinese Pharmacopoeia(Vol. Ⅳ), this study employed gas chromatography(GC) and single-factor experiments to optimize the preparation method of methyl ricinoleate from CrEL. The conversion coefficient between the two was validated, and the optimal sample preparation method was used to process microemulsion extracts of Zexie Decoction from three batches. The content of methyl ricinoleate generated was determined, and the content of CrEL in the microemulsion extracts of Zexie Decoction was calculated using the above conversion coefficient. The results showed that the optimal preparation method for CrEL was determined. Specifically, 10 mL of 1 mol·L~(-1) KOH-methanol solution was heated at 60 ℃ for 15 min in a water bath. Subsequently, 10 mL of boron trifluoride etherate-methanol(1∶3) solution was heated at 60 ℃ for 15 min in a water bath, followed by extraction with n-hexane twice. CrEL could stably produce 20.84% methyl ricinoleate. According to this conversion coefficient, the average mass concentration of CrEL in the three batches of Zexie Decoction microemulsion extracts was 11.94 mg·mL~(-1), which was not significantly different from the CrEL mass concentration of 11.57 mg·mL~(-1) during microemulsion formulation, indicating that the established content determination method of this study was highly accurate, sensitive, and repeatable. It can be used for subsequent research on microemulsion extracts of Zexie Decoction and provide a reference for quality control of other drug formulations containing CrEL.


Asunto(s)
Aceite de Ricino , Polietilenglicoles , Polietilenglicoles/química , Metanol , Tensoactivos/química , Solventes , Agua/química , Emulsiones/química
3.
World J Psychiatry ; 13(8): 524-532, 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37701547

RESUMEN

BACKGROUND: Antidepressants, particularly selective serotonin reuptake inhibitors, are currently considered the first-line treatment for panic disorder (PD). However, little is known about the relationship between the biomarkers that may predict better treatment. AIM: To compare genome-wide methylation and gene expression patterns between responsive and non-responsive patients with PD after 4 wk of escitalopram treatment. METHODS: Thirty patients with PD were enrolled in this study (responders = 13; non-responders = 17). All patients were assessed using the PD Severity Scale-Chinese version before and after treatment. The Illumina Infinium MethylationEPIC (850k) BeadChip for genome-wide methylation screening and mRNA sequencing was used in all patients with PD. RESULTS: A total of 701 differentially methylated positions (DMPs) were found between responders and non-responders (|Δß| ≥ 0.06, q < 0.05), and the hyper- and hypomethylated CpG sites were 511 (72.9%) and 190 (27.1%), respectively. Relative to non-responders, there were 59 differential transcripts, of which 20 were downregulated and 39 were upregulated (q < 0.05). However, no differentially expressed genes were identified by mRNA sequencing after correcting for multiple testing (|log2(FC)| > 1, q > 0.05). CONCLUSION: This preliminary study showed that DMPs might be associated with the treatment response to escitalopram in PD; however, these DMPs need to be verified in large samples.

4.
World J Psychiatry ; 13(7): 435-443, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37547739

RESUMEN

BACKGROUND: Genetic factors play an important role in the pathogenesis of panic disorder (PD). However, the effect of genetic variants on PD remains controversial. AIM: To evaluate the associations between glutamate decarboxylase 1 (GAD1) gene polymorphisms and PD risk and assess the effect of GAD1 gene polymorphisms on the severity of clinical symptoms in PD. METHODS: We recruited 230 PD patients and 224 healthy controls in this study. All participants were assessed for anxiety and panic symptom severity using the Hamilton Anxiety Rating Scale (HAM-A) and Panic Disorder Severity Scale (PDSS). GAD1 gene polymorphisms (rs1978340 and rs3749034) were genotyped and assessed for allele frequencies. RESULTS: There were no significant differences between cases and controls in the genotype distributions or allele frequencies of GAD1 (rs1978340 and rs3749034). In addition, the effect of GAD1 (rs1978340 and rs3749034) on PD severity was not significant. However, regarding respiratory symptoms, patients with the GAD1 rs1978340 A/A genotype had significantly higher scores than those with the A/G or G/G genotype. CONCLUSION: Here, we showed that the A/A genotype of GAD1 rs1978340 was associated with increased severity of respiratory symptoms in patients with PD.

5.
Zhongguo Gu Shang ; 36(8): 714-8, 2023 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-37605908

RESUMEN

OBJECTIVE: To explore clinical effects of repairing skin and soft tissue defect of finger with free posterior interosseous artery perforator flap. METHODS: Totally 8 patients with finger skin and soft tissue defect repaired with free posterior interosseous artery perforator flap were treated from May 2021 to November 2022, including 7 males and 1 female aged from 24 to 54 years old, and soft tissue defect area ranged from 3.0 cm×1.5 cm to 5.0 cm×3.0 cm. The time from injury to flap repair ranged from 3 to 83 h. The free posterior interosseous artery perforator flap was applied to repair finger defect, the area of the flap ranged from 3.5 cm×2.0 cm to 5.2 cm×3.5 cm, the donor area of flap was sutured directly. The survival, appearance, texture and donor complications of the flap were observed after operation, and Dargan functional standard was used to evaluate clinical effect of finger function. RESULTS: All flap of 8 patients were survived, and followed up from 3 to 12 months. There was no obvious swelling, soft texture, obvious pigmentation, linear intaglio in donor area only, and without obvious complications were found. Among them, 3 patients'skin flaps were repaired for the defect of palm of the fingers, and sensory recovery was good, two-point discrimination ranged from 5 to 9 mm. According to Dargan functional evaluation, 3 patients excellent, and 5 good. CONCLUSION: Free posterior interosseous artery perforation branch flap could be used to repair the defect of finger. The thickness of flap is moderate, operation is convenient, appearance and texture of the operative flap are good, and the donor site is small without obvious complications, and obtain satisfactory clinical effect.


Asunto(s)
Colgajo Perforante , Masculino , Humanos , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Dedos , Extremidad Superior , Arteria Cubital , Piel
6.
Small ; 19(37): e2302301, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37140089

RESUMEN

Social biotic colonies often perform intricate tasks by interindividual communication and cooperation. Inspired by these biotic behaviors, a DNA nanodevice community is proposed as a universal and scalable platform. The modular nanodevice as the infrastructure of platform contains a DNA origami triangular prism framework and a hairpin-swing arm machinery core. By coding and decoding a signal domain on the shuttled output strand in different nanodevices, an orthogonal inter-nanodevice communication network is established to connect multi-nanodevices into a functional platform. The nanodevice platform enables implementation of diverse tasks, including signal cascading and feedback, molecular input recording, distributed logic computing, and modeling of simulation for virus transmission. The nanodevice platform with powerful compatibility and programmability presents an elegant example of the combination of the distributed operation of multiple devices and the complicated interdevice communication network, and may become a new generation of intelligent DNA nanosystems.


Asunto(s)
ADN , Lógica , ADN/química
8.
Zhongguo Zhong Yao Za Zhi ; 48(1): 82-95, 2023 Jan.
Artículo en Chino | MEDLINE | ID: mdl-36725261

RESUMEN

With the approach of untargeted metabolomics and correlation analysis, this study aimed to explore the mechanism of Aurantii Fructus from Lingnan region in alleviating dryness by analyzing the different effects of raw Aurantii Fructus(RAF) and processed Aurantii Fructus(PAF) on fecal endogenous metabolism in normal rats. Eighteen Sprague-Dawley(SD) rats were randomly divided into a control group(C), an RAF group(10 g·kg~(-1)), and a PAF group(10 g·kg~(-1)). After seven days of administration, the effects of RAF and PAF on dryness-related indexes were compared, including water intake, fecal water content, salivary secretion, the expression of AQP5, VIP, and 5-HT in the submandibular gland, as well as the expression of AQP3, VIP, and 5-HT in the colon. The fecal samples in each group were determined by LC-MS. Multivariate statistical analysis and Pearson correlation coefficient were used for screening the differential metabolites and metabolic pathways in alleviating dryness of RAF. The results indicated that both RAF and PAF showed certain dryness, and the dryness of RAF was more significant. Moreover, PAF could alleviate dryness of RAF to a certain extent by reducing the water intake, fecal water content, and the expression of AQP3, VIP, and 5-HT in the colon and increasing the salivary secretion and the levels of AQP5, VIP, and 5-HT in the submandibular gland. According to the analysis of fecal metabolomics, 99 and 58 metabolites related to dryness were found in RAF and PAF respectively, where 16 of them played an important role in alleviating dryness of RAF. Pathway analysis revealed that the mechanism of PAF in alleviating dryness of RAF was presumably related to the regulation of riboflavin metabolism, purine metabolism, arginine biosynthesis, pyrimidine metabolism, alanine metabolism, aspartate metabolism, glutamate metabolism, and retinol metabolism pathways. This study suggested that PAF might alleviate dryness of RAF by affecting the metabolic levels of the body, which provides a new basis for further clarifying the processing mechanism of PAF.


Asunto(s)
Medicamentos Herbarios Chinos , Ratas , Animales , Medicamentos Herbarios Chinos/farmacología , Ratas Sprague-Dawley , Serotonina , Metabolómica , Agua
9.
Biosens Bioelectron ; 220: 114828, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36327905

RESUMEN

MicroRNAs (miRNAs) play an important role in post-transcriptional regulation of gene expression. However, methods to accurately detect miRNA activity in living cells are still limited. Here we developed a DNA nanomachine initiated by a miRNA-induced silencing complex (miRISC) for imaging miRNA activity in living cells. miRISC-mediated RNA cleavage reaction activated the DNA nanomachine by the specific cleavage of an RNA strand on the machine, resulting in autonomous movement of the walking leg around the AuNP surface with the release of a large number of fluorescently labeled DNA strands. The DNA nanomachine was successfully applied to detect miR-21 activity in three cell lines with different miR-21 expression profiles. We also demonstrated that terminal uridylyltransferase Tut4 knockdown by siRNA significantly increased the activity of let-7b miRNA, which further verifies the versatility of our DNA nanomachine. This new nanomachine has distinct advantages compared with reported methods for detecting miRNA activity, including simple operating procedures, short analysis time and sensitive signal output. Collectively, this work not only expands the application of the DNA nanomachine in the detection of miRNA activity, but also provides a promising tool for basic research in cell biology and development of clinical biomedicine.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , MicroARNs , MicroARNs/análisis , Técnicas Biosensibles/métodos , ADN/genética , Línea Celular
10.
Int J Anal Chem ; 2022: 5834525, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36458111

RESUMEN

Citrus reticulata "Chachi" (CRC) leaves contain abundant flavonoids, indicating that they possess good nutritional/pharmacological research and development potential. This study aims to explore chemical antioxidant quality markers based on the spectrum-effect relationship and quality control strategy of CRC leaves. The ultrahigh performance liquid chromatography (UPLC) system was used to establish chromatographic fingerprints of Citrus reticulata "Chachi" leaves. Simultaneously, they were evaluated by using similarity analysis (SA), hierarchical cluster analysis (HCA), and principal component analysis (PCA). Afterwards, the DPPH assay was adopted to study the antioxidant effects. The spectrum-effect relationship between UPLC fingerprints and DPPH radical-scavenging activities was studied with grey relational analysis (GRA). Analysis results indicated that there were twenty-one common peaks of fourteen batches of CRC leaves which were from different regions of Guangdong province, and their similarities ranged from 0.648 to 0.997. HCA results showed that fourteen batches of samples of CRC leaves could be divided into six classes at Euclidean distance of 5. The results from GRA showed that tangeretin and hesperidin were the main flavonoids responsible for the antioxidant activity in CRC leaves. In conclusion, this research established a chromatographic analysis method suitable for CRC leaves and demonstrated that chromatographic fingerprints analysis combined with the antioxidant activity could be used to evaluate the material basis of CRC leaves and may provide a reference to establish a quality standard.

11.
Vet Sci ; 9(10)2022 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-36288183

RESUMEN

Egg production in chickens is a quantitative trait. The aim of this study was to investigate the effect of promoter methylation of the Zona pellucida 2 (ZP2) gene on egg production. Real-time fluorescence quantification showed that the expression of the ZP2 gene in the ovaries of 300-day-old Jinghai yellow chickens in the high-laying group was significantly higher than that in the low-laying group (p < 0.01). A series of deletion fragments of the ZP2 gene promoter in Jinghai yellow chickens had different promoter activities in DF-1 cells, and the core region of the ZP2 gene promoter was found to be between −1552 and −1348. Four CpG islands in the promoter region of the ZP2 gene were detected by software prediction. The overall degree of methylation of the ZP2-1 amplified fragment was negatively correlated with mRNA expression to some extent (R = −0.197); the overall degree of methylation of the ZP2-2 amplified fragment was also negatively correlated with mRNA expression to some extent (R = −0.264), in which the methylation of methylcytosine (mC)-9, mC-20, and mC-21 sites was significantly negatively correlated with mRNA expression (p < 0.05). In addition, the mC-20 and mC-21 sites are located on the Sp1 transcription factor binding site, and it is speculated that these two sites may be the main sites for regulating transcription. In summary, the methylation sites mC-20 and mC-21 of the ZP2 gene may inhibit the binding of Sp1 and DNA, affect the transcription of the ZP2 gene, and then affect the number of eggs produced by the Jinghai yellow chickens.

12.
Zhongguo Zhong Yao Za Zhi ; 47(13): 3481-3487, 2022 Jul.
Artículo en Chino | MEDLINE | ID: mdl-35850799

RESUMEN

The index weight coefficients were determined by comparing the analytic hierarchy process(AHP), the criteria importance through inter-criteria correlation(CRITIC), and the AHP-CRITIC mixed weighting method. The comprehensive scores of index components(echinacoside, salvianolic acid B, paeoniflorin, and ointment yield) of each group in the orthogonal test were compared to optimize the extraction process of Congrong Shujing Granules. The results showed that the AHP-CRITIC mixed weighting method scientifically optimized the extraction process. To be specific, the decoction pieces should be added with the 6-fold amount of water and extracted twice, 1 h each time. After three verification tests, the average mass fractions of echinacoside, salvianolic acid B, and paeoniflorin were 0.72, 9.34, and 5.92 mg·g~(-1), respectively, and the average ointment yield was 47.18%. As verified by the AHP-CRITIC mixed weighting method and the orthogonal test, the optimized extraction process of Congrong Shujing Granules was stable and feasible and could be applied to industrial production.


Asunto(s)
Medicamentos Herbarios Chinos , Pomadas , Agua
13.
Fitoterapia ; 160: 105227, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35662650

RESUMEN

A pair of differential epimers with opposite C-7 configurations, crenatosides A and B (1 and 2), and 10 known phenylethanoid glycosides (PhGs) (3-12) were obtained from the succulent stem of Cistanche tubulosa. The structures were elucidated based on extensive spectral data (UV, IR, 1D and 2D NMR, HR-ESIMS), which are first reported natural products with unique glycoside structures. After acid hydrolysis, the configuration of the sugar was determined by comparing it with the normative sugar by HPLC. The absolute configurations of both compounds were determined by ECD spectrum analysis. All the obtained compounds were examined for their inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse microglial cells (BV-2 cells), and compounds 1 and 2 showed potent inhibition on NO production with IC50 values of 5.62 µM and 6.30 µM, respectively.


Asunto(s)
Cistanche , Alcohol Feniletílico , Animales , Glicósidos/química , Glicósidos/farmacología , Ratones , Estructura Molecular , Óxido Nítrico , Alcohol Feniletílico/farmacología , Azúcares
14.
Orthop Surg ; 14(5): 946-954, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35441488

RESUMEN

OBJECTIVE: To observe expression of CD38, a key modulator of nicotinamide dinucleotide (NAD+) metabolism in mice with knee osteoarthritis, and protective effect of CD38 inhibition during the osteoarthritis (OA) development. METHOD: The destabilization of the medial meniscus (DMM) model was performed in mice to mimic the process of OA. Immunofluorescence of CD38 was performed to evaluate its response during the OA process. Limb bud-derived mesenchymal cells were isolated for micromass culture. 100 nM or 1 µM CD38 inhibitor (78c) treatment for 14 days and CD38 sgRNA infection were then used to explore the effects of chondrogenic differentiation via Alcian blue staining. The expressions of chondrogenic markers were detected using RT-PCR and Western blot. To explore the protective effect of CD38 inhibitor on cartilage degradation during OA in vivo, a CD38 inhibitor was injected into the knee joint after DMM operations. Micro-CT analysis and Safranin O-fast green staining were used to evaluate subchondral bone micro-architecture changes and cartilage degeneration. RESULTS: Compared to the control group, the CD38 expression in superficial cartilage was obviously increased in DMM group (P < 0.05). During the normal chondrogenic differentiation, the extracellular matrix formed and expression of Sox9, Col2, aggrecan increased apparently while CD38 expression decreased, which could be reversed with ablation of CD38 in limb bud-derived mesenchymal cells. Consistent with findings in vitro, CD38 blockage via CD38 inhibitor injection protected against osteosclerosis in medial subchondral bone and cartilage degeneration in DMM-induced experimental mice. Compared to the Sham group, DMM mice showed significantly increased values of BV and BV/TV in subchondral bone (P < 0.05) and Mankin score, which could be rescued by 78c treatment (P < 0.05). Also the CD38 inhibitor contributed to homeostasis of anabolism and catabolism by upregulating Sox9, Col2, aggrecan and downregulating Runx2, Col10 and Mmp13. CONCLUSION: This study primarily implicates CD38 as an important regulator of chondrogenic differentiation. Inhibition of CD38 demonstrated protection against cartilage degeneration, which suggests that CD38 could be a potential therapeutic target for OA.


Asunto(s)
ADP-Ribosil Ciclasa 1 , Cartílago Articular , Glicoproteínas de Membrana , Osteoartritis de la Rodilla , ADP-Ribosil Ciclasa 1/metabolismo , Agrecanos , Animales , Cartílago Articular/fisiopatología , Condrocitos , Modelos Animales de Enfermedad , Homeostasis , Glicoproteínas de Membrana/metabolismo , Meniscos Tibiales/cirugía , Ratones , Osteoartritis de la Rodilla/metabolismo
15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(1): 109-113, 2022 Jan.
Artículo en Chino | MEDLINE | ID: mdl-35048609

RESUMEN

OBJECTIVE: To investigate the relationship between sleep duration and depressive symptoms in older people in China, and to explore whether there are gender differences in the relationship. METHODS: Accessing the data from China Health and Retirement Longitudinal Study (CHARLS) for 2015 and 2018, we covered in the study a total of 2898 respondents, including 1684 males (58.1%) and 1214 females (41.9%). The 10-item form of Center for Epidemiological Studies Depression Scale (CES-D) was used to measure the depressive symptoms of the older people. The effects of sleep duration on depressive symptoms of older people in China were analyzed with the logistic model. Based on the depressive and non-depressive subgroups in 2018, the differences of health factor variables and sleep duration between 2015 and 2018 were studied. Adjustments were made for health factors presenting statistical differences in 2018 to further explore the stability of the analysis results. RESULTS: Among the female older people, those with short sleep duration and those with long sleep duration had increased risks of developing depressive symptoms [odds ratio ( OR)=1.815, 95% confidence interval ( CI): 1.357-2.429 and OR=1.364, 95% CI: 1.001-1.854, respectively] in comparison to those with normal sleep duration. Among the male older people, no connection was identified between sleep duration and risks for depressive symptoms ( P>0.05). Residing in rural areas, suffering from chronic diseases and having limited ability for Instrumental Activities of Daily Living (IADL) were risk factors for developing depressive symptoms ( P<0.05). The sleep duration for 2015 and that for 2018 were found to be statistically different in the depressive older people ( P<0.001), but no no statistically significant difference was found between the sleep duration for 2015 and that for 2018 among the non-depressive older people. Findings for chronic diseases and IADL for 2015 and those for 2018 were statistically different in the depressive older population ( P<0.001). In the non-depressive older population, findings for chronic diseases, IADL and tobacco smoking status for 2015 and those for 2018 showed statistical difference ( P<0.05). Further sensitivity analysis showed that in the female older population, short sleep duration increased the risks for depressive symptoms ( OR=1.819, 95% CI: 1.356-2.440, P<0.001), while long sleep duration did not affect the risks for depressive symptoms. In the male older population, short or long sleep duration were not associated with the risks for depressive symptoms. CONCLUSION: The association between sleep duration and the risks for depressive symptoms was different for men and women. For the female older population, the possibility of depressive symptoms should be considered for those with short or long sleep duration. For the male older population, short or long sleep duration had little impact on the risks for depressive symptoms.


Asunto(s)
Actividades Cotidianas , Depresión , Anciano , China/epidemiología , Estudios de Cohortes , Depresión/epidemiología , Depresión/etiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Sueño
16.
Appl Microbiol Biotechnol ; 105(24): 9153-9166, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34837493

RESUMEN

To directly produce ß-alanine from glucose by microbial fermentation, a recombinant Corynebacterium glutamicum strain with high efficiency of ß-alanine production was constructed in this study. To do this, the biosynthetic pathway of ß-alanine in an L-lysine-producing strain XQ-5 was modified by enhancing carbon flux in biosynthetic pathway and limiting carbon flux in competitive pathway. This study showed that replacement of L-aspartate kinase (AK) with wild-type AK and disruption of lactate dehydrogenase and alanine/valine aminotransferases increase ß-alanine production because of decreasing the by-products accumulation. Moreover, L-aspartate-α-decarboxylase (ADC) from Bacillus subtilis was designed as the best enzyme for increasing ß-alanine production, and its variant (BsADCE56S/I88M) showed the highest activity for catalyzing L-aspartate to generate ß-alanine. To further increase ß-alanine production, expression level of BsADCE56S/I88M was controlled by optimizing promoter and RBS, indicating that Pgro plus ThirRBS is the best combination for BsADCE56S/I88M expression and ß-alanine production. The resultant strain XQ-5.5 produced 30.7 ± 2.3 g/L of ß-alanine with a low accumulation of lactate (from 5.2 ± 0.14 to 0.2 ± 0.09 g/L) and L-alanine (from 7.6 ± 0.22 to 3.8 ± 0. 32 g/L) in shake-flask fermentation and produced 56.5 ± 3.2 g/L of ß-alanine with a productivity of 0.79 g/(L·h) and the glucose conversion efficiency (α) of 39.5% in feed-batch fermentation. This is the first report of genetically modifying the biosynthetic pathway of ß-alanine that improves the efficiency of ß-alanine production in an L-lysine-producing strain, and these results give us a new insight for constructing the other valuable biochemical. KEY POINTS: • Optimization and overexpression of the key enzyme BsADC increased the accumulation of ß-alanine. • The AK was replaced with wild-type AK to increase the conversion of aspartic acid to ß-alanine. • A 56.5-g/L ß-alanine production in fed-batch fermentation was achieved.


Asunto(s)
Corynebacterium glutamicum , Vías Biosintéticas/genética , Corynebacterium glutamicum/genética , Glucosa , Ingeniería Metabólica , beta-Alanina
17.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2481-2488, 2021 May.
Artículo en Chino | MEDLINE | ID: mdl-34047094

RESUMEN

The paclitaxel-loaded and folic acid-modified poly(lactic-co-glycolic acid) nano-micelles(PTX@FA-PLGA-NMs) were prepared by the emulsion solvent evaporation method, and the parameters of paclitaxel-loaded nano-micelles were optimized with the particle size and PDI as evaluation indexes. The morphology of the nano-micelles was observed by transmission electron microscopy(TEM), and the stability, drug loading and encapsulation efficiency were systematically investigated. In vitro experiments were performed to study the cytotoxic effects of nano-micelles, apoptosis, and cellular uptake. Under the optimal parameters, the nano-micelles showed the particle size of(125.3±1.2) nm, the PDI of 0.086±0.026, the zeta potential of(-20.0±3.8) mV, the drug loading of 7.2%±0.75%, and the encapsulation efficiency of 50.7%±1.0%. The nano-micelles were in regular spherical shape as observed by TEM. The blank FA-PLGA-NMs exhibited almost no inhibitory effect on the proliferation and growth of tumor cells, while the drug-loaded nano-micelles and free PTX exhibited significant inhibitory effects. The IC_(50) of PTX@FA-PLGA-NMs and PTX was 0.56 µg·mL~(-1) and 0.66 µg·mL~(-1), respectively. The paclitaxel-loaded nano-micelles were potent in inhibiting cell migration as assessed by the scratch assay. PTX@FA-PLGA-NMs had good pro-apoptotic effect on cervical cancer HeLa cells and significantly promoted the uptake of HeLa cells. The results of in vitro experiments suggested that PTX@FA-PLGA-NMs could target and treat cervical cancer HeLa cells. Therefore, as nanodrug carriers, PTX@FA-PLGA-NMs with anti-cancer activity are a promising nano-system for improving the-rapeutic effects on tumors.


Asunto(s)
Antineoplásicos Fitogénicos , Neoplasias del Cuello Uterino , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Portadores de Fármacos , Femenino , Ácido Fólico , Glicolatos , Células HeLa , Humanos , Micelas , Paclitaxel , Tamaño de la Partícula , Neoplasias del Cuello Uterino/tratamiento farmacológico
18.
Adv Physiol Educ ; 44(4): 726-733, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33155832

RESUMEN

Current interdisciplinary medical training calls for reforms and innovations in the assessment of pathophysiology education. Formative assessment is used to monitor student learning to provide ongoing feedback that can improve both learning and teaching. Beginning in 2016, we implemented a formative assessment composed of case-based multiple-choice questions (MCQs) for all students in all majors. In 2017, case study questions began to be employed in the formative assessment, and student-set, case-based questions were further introduced. Aiming to gather the students' suggestions and feedback on the mixed-method assessment, we conducted a survey on aspects such as the effectiveness of the assessment, assessment content and completion, opinions on student-set questions, and the impact on pathophysiology learning for students from 2017 to 2019. In addition, we compared students' semesterly final scores with those of previous students and evaluated the relationship between formative and summative assessment scores. The results for 1,277 students clearly showed that the reformed formative assessment system was well received by the students. The students thought that the formative assessment not only allowed for the provision of real-time feedback on the effectiveness of teaching and learning but also nurtured self-motivation, the development of analytical and problem-solving skills, and collaborative efforts. Both the semesterly final scores and the proportions of students scoring in higher score ranges increased after the implementation of the formative assessment, and the summative assessment scores were positively related to the formative assessment scores. Consequently, the reformed formative assessment system significantly improved the quality of pathophysiology education.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Evaluación Educacional , Retroalimentación , Humanos , Encuestas y Cuestionarios
19.
Bone Joint Res ; 9(7): 368-385, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32793332

RESUMEN

A balanced inflammatory response is important for successful fracture healing. The response of osteoporotic fracture healing is deranged and an altered inflammatory response can be one underlying cause. The objectives of this review were to compare the inflammatory responses between normal and osteoporotic fractures and to examine the potential effects on different healing outcomes. A systematic literature search was conducted with relevant keywords in PubMed, Embase, and Web of Science independently. Original preclinical studies and clinical studies involving the investigation of inflammatory response in fracture healing in ovariectomized (OVX) animals or osteoporotic/elderly patients with available full text and written in English were included. In total, 14 articles were selected. Various inflammatory factors were reported; of those tumour necrosis factor-α (TNF-α) and interleukin (IL)-6 are two commonly studied markers. Preclinical studies showed that OVX animals generally demonstrated higher systemic inflammatory response and poorer healing outcomes compared to normal controls (SHAM). However, it is inconclusive if the local inflammatory response is higher or lower in OVX animals. As for clinical studies, they mainly examine the temporal changes of the inflammatory stage or perform comparison between osteoporotic/fragility fracture patients and normal subjects without fracture. Our review of these studies emphasizes the lack of understanding that inflammation plays in the altered fracture healing response of osteoporotic/elderly patients. Taken together, it is clear that additional studies, preclinical and clinical, are required to dissect the regulatory role of inflammatory response in osteoporotic fracture healing. Cite this article: Bone Joint Res 2020;9(7):368-385.

20.
Genes (Basel) ; 11(5)2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-32349370

RESUMEN

Interleukin 8 (IL-8) participates in the immune response and has the function of inducing neutrophils to release lysosomal enzymes and eliminate pathogens. This study was to investigate the effect of single nucleotide mutations in the IL-8 gene promoter region on the coccidiosis resistance index. In this study, 180 infected Eimeria tenella (E. tenella) Jinghai yellow chickens were used as experimental samples. DNA sequencing technology was used to detect single nucleotide polymorphisms (SNPs) in the IL-8 gene promoter region. The association between these SNPs and coccidiosis resistance indexes (including superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-PX), catalase (CAT), nitric oxide (NO), interleukin-1ß (IL-1ß), interleukin-2 (IL-2), interleukin-6 (IL-6), IL-8, and interferon-γ (IFN-γ)) were analyzed. Three SNPs (T-550C, G-398T, and T-360C) were detected. Significant associations were found between each genotype at the T-550C site with NO (p-value = 0.006) and IL-8 (p-value = 0.034) indexes. Significant associations were found between each genotype at the G-398T site with SOD (p-value = 0.042), CAT (p-value = 0.049), NO (p-value = 0.008), and IL-2 (p-value = 0.044) indexes. Significant associations were found between each genotype at the T-360C site with SOD (p-value = 0.007), NO (p-value = 0.046), IL-2 (p-value = 0.041), IL-8 (p-value = 0.039), and IFN-γ (p-value = 0.042) indexes. Haplotype analysis showed that multiple indexes of the H1H3 haplotype combination were significantly higher than other haplotype combinations. Therefore, mutation of the IL-8 gene promoter region has a significant regulatory effect on the coccidiosis resistance index, with a change in transcription factor binding potentially altering IL-8 gene expression, thereby further affecting the IL-8 level in plasma. However, the specific mechanism needs further study.


Asunto(s)
Pollos/genética , Coccidiosis/genética , Resistencia a la Enfermedad/genética , Interleucina-8/genética , Animales , Pollos/parasitología , Coccidiosis/parasitología , Eimeria tenella/patogenicidad , Regulación de la Expresión Génica/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética
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