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1.
J Cell Mol Med ; 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31957265

RESUMO

This study sought to find more exon mutation sites and lncRNA candidates associated with type 2 diabetes mellitus (T2DM) patients with obesity (O-T2DM). We used O-T2DM patients and healthy individuals to detect mutations in their peripheral blood by whole-exon sequencing. And changes in lncRNA expression caused by mutation sites were studied at the RNA level. Then, we performed GO analysis and KEGG pathway analysis. We found a total of 277 377 mutation sites between O-T2DM and healthy individuals. Then, we performed a DNA-RNA joint analysis. Based on the screening of harmful sites, 30 mutant genes shared in O-T2DM patients were screened. At the RNA level, mutations of 106 differentially expressed genes were displayed. Finally, a consensus mutation site and differential expression consensus gene screening were performed. In the current study, the results revealed significant differences in exon sites in peripheral blood between O-T2DM and healthy individuals, which may play an important role in the pathogenesis of O-T2DM by affecting the expression of the corresponding lncRNA. This study provides clues to the molecular mechanisms of metabolic disorders in O-T2DM patients at the DNA and RNA levels, as well as biomarkers of the risk of these disorders.

2.
Medicine (Baltimore) ; 99(2): e18717, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914085

RESUMO

BACKGROUND: Cardiac masses are rare, but lead to high risk of stroke and death. Because of the different treatment methods, it is significant for clinicians to differentiate the nature of masses. Cardiac magnetic resonance (CMR) imaging has high intrinsic soft-tissue contrast and high spatial and temporal resolution and can provide evidence for differential diagnosis of cardiac masses. However, there is no evidence-based conclusion as to its accuracy. Therefore, the purpose of our study is to perform a systematic review on this issue and provide useful information for clinical diagnosis and treatment. METHODS: We will perform a systematic search in EMBASE, Cochrane Library, PubMed and Web of Science for diagnostic studies using CMR to detect cardiac masses from inception to October, 2019. Two authors will independently screen titles and abstracts for relevance, review full texts for inclusion and conduct detail data extraction. The methodological quality will be assessed using the QUADAS-2 tool. If pooling is possible, we will use bivariate model for diagnostic meta-analysis to estimate summary sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of CMR, as well as different sequences of CMR. Estimates of sensitivity and specificity from each study will be plotted in summary receive operating curve space and forest plots will be constructed for visual examination of variation in test accuracy. If enough studies are available, we will conduct sensitivity analysis and subgroup analysis. RESULTS: The results of this systematic review and meta-analysis will be published in a peer-reviewed journal. CONCLUSION: To our knowledge, this will be the first systematic review on the accuracy of CMR in the differential diagnosis of cardiac masses. This study will provide evidence and data to form a comprehensive understanding of the clinical value of CMR for cardiac masses patients. ETHICS AND DISSEMINATION: Ethics approval and patient consent are not required, as this study is a systematic review. PROSPERO REGISTRATION NUMBER: CRD42019137800.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31927938

RESUMO

With the rapidly increasing development of portable device hardware and flexible electronics, ultrathin electromagnetic interference (EMI) shielding films with the combination of high flexibility and excellent mechanical properties are noticeably required. In addition to minimize the electromagnetic wave pollution problem, the fire hazards caused by accidental electrical leakage or aging should also cause extensive concern. Inspired by nacre and sandwich structure, herein, we firstly fabricate an electrical insulating sandwich structured film based on Ca ion crosslinked sodium alginate (SA)-montmorillonite (MMT) and Ti3C2Tx MXene through step-by-step vacuum-assisted filtration process. This novel design strategy not only maintains the inner EMI shielding network, but also can act as an excellent fire resistant barrier to protect the electron device once accidental fire happens. Compared with the pure Ti3C2Tx layer, such kind of sandwich film can effectively keep the EMI shielding performance (50.01 dB), dramatically enhance the mechanical properties (84.4 MPa) and obtain excellent fire resistant performance. Especially, compared with the film by mixture, the EMI SE value is only 55% of sandwich films. Besides, it functions well under long-term heat aging test at 80 °C. Therefore, this unique design provides a novel EMI material strategy to facilitate its future application in flexible electronics.

4.
Food Chem ; 308: 125650, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655477

RESUMO

This study aimed at investigating the formation and accumulation of 16 reactive aldehydes in clam (Ruditapes philippinarum) during oil frying in both the tissue and the oil using an HPLC-ESI-MS/MS methodology. After processing, the accumulation of acrolein, crotonaldehyde, pentanal, trans-2-hexenal, hexanal, trans, trans-2,4-heptadienal, heptanal, nonanal, trans, trans-2,4-decadienal and 4-hydroxy-2-nonenal was most noticeable in both fried clam and frying oil. Most of the aldehyde species showed a time- and temperature-dependent manner of formation and accumulation during frying due to continuous oxidative degradation under conditions employed. However, several species of aldehyde such as acrolein and trans-2-pentenal slightly decreased at higher temperatures and/or longer frying times, which may be due to the imbalance toward disappearance of aldehydes resulting from their evaporation under the extreme conditions. Presence of natural polyphenols in bamboo leaves significantly prevented the formation of aldehydes in both fried clam and frying oil due to their antioxidant activity (P < 0.05).


Assuntos
Aldeídos/química , Bivalves/química , Animais , Cromatografia Líquida de Alta Pressão , Culinária , Temperatura Alta , Oxirredução , Espectrometria de Massas em Tandem
5.
Int J Biol Macromol ; 143: 1-10, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31809778

RESUMO

Chitosan (CS) and phosphorylated chitosan (PCS) were deposited onto the polyamide 66 (PA66) fabric surfaces along with poly-acrylate sodium (PAS) via 'one pot' and layer by layer (LbL) assembly methods in preparing flame retardant coatings. Subsequently, to stabilize the deposited coatings, some of the fabric samples were treated under the UV-irradiation and additionally, a thermal treatment was also carried out for the remaining fabric samples. The LbL assembled fabrics showed a better homogeneity in the coating structure over the one pot deposited fabrics as appeared in scanning electron microscopy (SEM). Nonetheless, the LbL treated fabric sample (i.e., PA66-10BL-UV) with a higher weight gain% exhibited a greater improvement in limiting oxygen index (LOI) (i.e., 23%), and a reduced peak heat release rate (pHRR) (i.e., 25%). Yet more, only the LbL assembled and thermally cross-linked fabric sample could able to retain the flame retardant behavior in the vertical burning test even after 5 washing cycles.

6.
Curr Microbiol ; 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811376

RESUMO

A Gram-stain-negative, rod-shaped, non-motile, facultatively anaerobic bacterium, designated FJ4-8T, was isolated from a rotten hemp rope in Chongqing City, PR China. Phylogenetic analysis of 16S rRNA gene sequences indicated that the isolate was closely related to members of the family Sphingobacteriaceae, with the highest similarity to Pedobacter tournemirensis TF5-37.2-LB10T (95.3%) and low similarities to all other species of the genus Pedobacter (90.4-93.9%). Phylogenetic analyses demonstrated that strain FJ4-8T formed a stable subclade with Pedobacter tournemirensis TF5-37.2-LB10T. The clade with these two strains branched adjacent to a clade containing three species of the genus Arcticibacter. MK-7 was detected as the only respiratory quinone. The major fatty acids composed iso-C15:0, iso-C17:0 3-OH and summed feature three. Phosphatidylethanolamine, three aminophospholipids and one unidentified lipid were found as the major polar lipids. The major polyamine was identified as sym-homospermidine. The DNA-DNA hybridization value between strain FJ4-8T and Pedobacter tournemirensis TF5-37.2-LB10T was 42.0 ± 2.5%. Based on its phylogenetic, chemotaxonomic and phenotypic characteristics, the novel strain and TF5-37.2-LB10T were found to be different from members of genera Pedobacter and Arcticibacter. FJ4-8T and TF5-37.2-LB10T represented different species. Therefore, FJ4-8T should be classified as a novel species of a novel genus in the family Sphingobacteriaceae, for which the name Pararcticibacter amylolyticus gen. nov., sp. nov. is proposed. The type strain is FJ4-8T (= KCTC 62640T = CCTCC AB 2018052T). The draft genome sequence is 6290, 449 bp in length, the genomic DNA G+C content was 44.4 mol%. Pedobacter tournemirensis TF5-37.2-LB10T should be transferred to the novel genus as Pararcticibacter tournemirensis comb. nov. (The type strain is TF5-37.2-LB10T (= DSM 23085T = CIP 110085T = MOLA 820T).

7.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3980-3990, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833712

RESUMO

The bioweathering of stone cultural relics is a ubiquitous problem. Weathering prevention is an escalating challenge under the increasing global climate and environmental changes. Here, the mechanisms of lichen-microorganism mediated weathering of stone materials and their relationships with climatic and environmental factors were reviewed. The biological protection of lichens and the evaluation of the efficacy of biocides in lichen-control were discussed. The potential research directions in this field were proposed. Research on lichen-rock interfaces suggested that biological weathe-ring could be mainly attributed to physical and chemical weathering which represented by mycelium penetration and calcium oxalate formation. Bioweathering of outdoor stone cultural relics is closely related with the whole ecosystem encompassing factors, such as stone matrix, surrounding environment, and climate factors. Lichens have both biological weathering and protection effects on stone heritage. For the restoration of bioweathered stone cultural relics, environmental conditions for pre-servation of stone cultural relics should be improved step by step. The related industry regulations and national standards for evaluating biological weathering and control efficiency should be established to promote the efficient development of scientific protection.

8.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4353-4360, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840482

RESUMO

The close interactions between abiotic and biotic components create a variety of three-dimensional (3-D) landscape patterns. Landscape ecology, as a discipline of studying patterns and ecological processes, has made rapid progress in the exploration of 3-D space with the improvement of data acquirement ability, such as lidar technology. The real surface landscape can be described considering 3-D data, which improves the consistency between landscape indices and ecological process, and has overcome the shortage of ecological meanings of traditional researches. However, the lack of universality of methods and conclusions still exist due to different study backgrounds. The sensitivities of research results will increase with the expansion from two-dimensional to 3-D scale because of the increasing data quantity and accuracy. How to select and process the suitable scaled data to get more scientific conclusions need to be discussed in the future. The integration of multi-scale, multi-source and a long time series data will be the study trend with data acquisition becoming more convenient. In addition to the dynamic monitoring and prediction studies, the sustainable and ecological restoration application combined with landscape planning and design will be an important research direction.

9.
Cell Microbiol ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829498

RESUMO

Hepatitis B virus (HBV) infection is a major cause of acute and chronic liver diseases. During the HBV life cycle, HBV hijacks various host factors to assist viral replication. In this research, we find that the HBV regulatory protein X (HBx) can induce the upregulation of DExH-box RNA helicase 9 (DHX9) expression by repressing proteasome-dependent degradation mediated by MDM2. Furthermore, we demonstrate that DHX9 contributes to viral DNA replication in dependence on its helicase activity and nuclear localization. In addition, the promotion of viral DNA replication by DHX9 is dependent on its interaction with Nup98. Our findings reveal that HBx-mediated DHX9 upregulation is essential for HBV DNA replication.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31849140

RESUMO

A photoinduced protocol for the direct B-H bond activation of NHC-borane via a SET process was unveiled for the first time. Contrast to the common HAT strategies, this photoinduced activation pathway simply takes advantage of the beneficial redox potentials of NHC-boranes, thus avoiding the involvement of extra radical initiators. The resulting NHC-boryl radical was easily apt to the borylation of a wide range of α-trifluoromethyl alkenes and alkenes with varied electronic and structural features, enabling facile accesses to divergent highly functionalized borylated molecules. The included labelling and photoquenching experiments provide insights into the mechanism of this photoinduced SET pathway.

11.
Front Immunol ; 10: 2721, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849942

RESUMO

Melanoma is the most serious type of skin cancer. The immunosuppressive tumor microenvironment and aberrant expression of some proto-oncogenes are the main cause of melanoma development. We have constructed a single-stranded RNA (ssRNA)-Pim-3-small hairpin RNA (shRNA) dual-function vector, which activates the toll-like receptor (TLR)7 to stimulate the antitumor immune response through ssRNA fragments and simultaneously silences the proto-oncogene Pim-3 to intensify apoptosis of the tumor cells via shRNA. Here, we found that therapy with the ssRNA-Pim-3-shRNA dual-function vector not only promotes the apoptosis and inhibits the proliferation of B16F10 melanoma cells by inhibiting the expression of Pim-3 but also enhances the activation of CD8+ T cells and natural killer (NK) cells and simultaneously reduces the proportion of intratumoral regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Together, these features effectively inhibit the growth of melanoma. Intriguingly, the bifunctional therapeutic effect that reverses the tumor immunosuppressive microenvironment is dependent on the activation of plasmacytoid dendritic cells (pDCs) and the secretion of type I interferon (IFN). Our study suggests that ssRNA-Pim-3-shRNA dual-function therapy is expected to become a promising therapeutic strategy for melanoma and other solid tumors with immunosuppressive microenvironment.

12.
Appl Opt ; 58(33): 9033-9038, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31873578

RESUMO

Lobster-eye optics has been proposed as a high-energy detection device with great potential for astronomical observation and safety inspection due to its large-field-of-view (FOV) focusing ability. In this paper, we study the relationship between the optimal structural parameters of the meridional lobster-eye lens and focusing efficiency. The maximum odd-reflection component, which relates only to the FOV and the channel ratio of depth to width, has been found. Furthermore, the structural constant C, which determines the optimal efficiency structure of the meridional lobster-eye lens, is revealed for hard x-rays. Meanwhile, by introducing accurate reflectivity of iridium in soft x-rays, the constraint of the effective FOV with respect to x-ray wavelength is analyzed. The research results can help to design the optimal structure of the lobster-eye lens in multiple spectra.

13.
BMJ Open ; 9(12): e033084, 2019 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-31871259

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy of transthoracic echocardiography (TTE) in patients with pulmonary hypertension (PH). DESIGN: Systematic review and meta-analysis. DATA SOURCES AND ELIGIBILITY CRITERIA: Embase, Cochrane Library for clinical trials, PubMed and Web of Science were used to search studies from inception to 19 June, 2019. Studies using both TTE and right heart catheterisation (RHC) to diagnose PH were included. MAIN RESULTS: A total of 27 studies involving 4386 subjects were considered as eligible for analysis. TTE had a pooled sensitivity of 85%, a pooled specificity of 74%, a pooled positive likelihood ratio of 3.2, a pooled negative likelihood ratio of 0.20, a pooled diagnostic OR of 16 and finally an area under the summary receiver operating characteristic curve of 0.88. The subgroup with the shortest time interval between TTE and RHC had the best diagnostic effect, with sensitivity, specificity and area under the curve (AUC) of 88%, 90% and 0.94, respectively. TTE had lower sensitivity (81%), specificity (61%) and AUC (0.73) in the subgroup of patients with definite lung diseases. Subgroup analysis also showed that different thresholds of TTE resulted in a different diagnostic performance in the diagnosis of PH. CONCLUSION: TTE has a clinical value in diagnosing PH, although it cannot yet replace RHC considered as the gold standard. The accuracy of TTE may be improved by shortening the time interval between TTE and RHC and by developing an appropriate threshold. TTE may not be suitable to assess pulmonary arterial pressure in patients with pulmonary diseases. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019123289.

14.
Biomolecules ; 9(11)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31717714

RESUMO

Schistosomiasis caused by Schistosoma japonicum is a major parasitic disease in the People's Republic of China. Liver fibrosis is the main pathological mechanism of schistosomiasis, and it is also the major lesion. The common drug used for its treatment, praziquantel (PZQ), does not have a marked effect on liver fibrosis. Resveratrol (RSV), which is an antioxidant, improves mitochondrial function and also attenuates liver fibrosis. The combination of PZQ and RSV has been found to have a synergistic antischistosomal effect on Schistosoma mansoni; additionally, the activity of PZQ is enhanced in the presence of RSV. Here, we examine the therapeutic effects of RSV on the S. japonicum infection in a mouse model, and we investigate RSV as a novel therapeutic agent for mitochondrial function and schistosomiasis-associated liver fibrosis (SSLF). Mitochondrial membrane potential was examined using flow cytometry analysis. The expression of the mitochondrial biogenesis genes PGC-α and fibrosis-associated genes collagen I, collagen III and α-SMA were examined using western blot analysis. Fibrosis-associated histological changes were examined using Masson trichrome staining. Additionally, the effects of RSV on S. japonicum adult worms were examined using scanning electron microscopy and transmission electron microscopy. RSV treatment improved mitochondrial function by increasing membrane potential and increasing PGC-α expression (mitochondrial biogenesis). Further, RSV attenuated liver injury, including liver scarring, by decreasing collagen deposition and the extent of fibrosis, based on the decrease in expression of the fibrosis-related genes. RSV also decreased the adult worm count and caused considerable physical damage to the worm. These results indicate that RSV upregulates mitochondrial biogenesis and inhibits fibrosis. RSV may have potential as a therapeutic target for the treatment of fibrosis in schistosomiasis.

15.
Yi Chuan ; 41(11): 1067-1072, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31735709

RESUMO

Genetic analysis is an important part of undergraduate genetics teaching and tetrad analysis is unique and integral for genetic analysis of fungi. The ordered tetrad in Neurospora is an important material for genetic analysis, which can not only be used to study recombination between genes and centromeres, but also between genes themselves, as well as study the fine cross patterns between non-sister chromatids of homologous chromosomes. However, in textbooks and related professional journals, there is a lack of specific introduction to the induction methods of the seven basic class asci used in two genes analysis. In the present paper, we designed a table presenting the correlation between the three tetrad types (PD, NPD, T) and the four segregation pattern groups (Ⅰ Ⅰ, Ⅱ Ⅱ, Ⅰ Ⅱ, Ⅱ Ⅰ) to visually show the 12 possible combinations (3×4=12). Then five of them were excluded through the "×" symbol and in addition with three comments attached with the table, thus finally we obtained seven basic ascus types. We hope that this analytical method can assist the teaching of ordered tetrad analysis in Neurospora.


Assuntos
Segregação de Cromossomos , Neurospora/genética , Centrômero , Meiose
16.
J Invest Dermatol ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31758945

RESUMO

The skin homeostasis is controlled by a complex interplay between tightly regulated transcription factors and signaling pathways. MYB is a transcription factor expressed in hair follicle progenitor cells and found overexpressed in adnexal skin tumors. However, the biological consequences of deregulated MYB expression in the skin remain poorly understood. To address this, we generated transgenic mice that overexpress MYB in epidermal and follicular keratinocytes. These mice exhibited a normal hair coat after birth, but gradually developed alopecia, accompanied by altered follicular differentiation, disrupted hair cycle and a marked depletion of hair follicle stem cells. Additionally, transgenic mice developed massive epidermal hyperplasia and hyperkeratosis. Global expression profiling not only confirmed that the skin of these mice exhibited transcriptomic features of alopecia and epidermal differentiation, but also revealed features of psoriasis and the inflammatory response. The latter was further confirmed by the increased T cell infiltration found in the skin of transgenic mice. Overall, these results suggest that tight regulation of MYB expression in the skin is critical to maintain skin homeostasis.

17.
J Cell Mol Med ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31762191

RESUMO

High rates of de novo lipid synthesis have been discovered in certain kinds of tumours, including gallbladder cancer (GBC). Unlike several other tumours, GBC is highly insensitive to standard adjuvant therapy, which makes its treatment even more challenging. Although several potential targets and signalling pathways underlying GBC chemoresistance have been revealed, the precise mechanisms are still elusive. In this study, we found that α-Mangostin, as a dietary xanthone, repressed the proliferation and clone formation ability, induced cell cycle arrest and the apoptosis, and suppressed de novo lipogenesis of gallbladder cancer cells. The underlying mechanisms might involve the activation of AMPK and, therefore, the suppression of SREBP1 nuclear translocation to blunt de novo lipogenesis. Furthermore, SREBP1 silencing by siRNA or α-mangostin enhanced the sensitivity of gemcitabine in gallbladder cancer cells. In vivo studies also displayed that MA or gemcitabine administration to nude mice harbouring NOZ tumours can reduce tumour growth, and moreover, MA administration can significantly potentiate gemcitabine-induced inhibition of tumour growth. Corroborating in vitro findings, tumours from mice treated with MA or gemcitabine alone showed decreased levels of proliferation with reduced Ki-67 expression and elevated apoptosis confirmed by TUNEL staining, furthermore, the proliferation inhibition and apoptosis up-regulation were obviously observed in MA combined with gemcitabine treatment group. Therefore, inhibiting de novo lipogenesis via targeting the AMPK/SREBP1 signalling by MA might provide insights into a potential strategy for sensitizing GBC cells to chemotherapy.

18.
Ophthalmic Physiol Opt ; 39(6): 451-458, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31696541

RESUMO

PURPOSE: To determine the differences in mean ocular dimensions between urban and rural children and identify possible influencing factors. METHODS: This work uses previously published data from the Shandong Children Eye Study, which was based on a random cluster sampling applied to a cross-sectional school-based study design in the rural Guanxian County and Weihai city. All children underwent auto-refractometry and biometry under cycloplegia. RESULTS: The study included 3290 children (aged 9.35 ± 2.93 years), consisting of 888 pairs of boys and 757 pairs of girls matched by sex, age and refractive error (each pair matching one child from urban cohort with one from the rural cohort). Overall urban children were significantly taller and heavier than rural children (t-test; p < 0.001), which was confirmed for all age groups for weight. Urban ocular axial lengths were significantly longer by 0.23 mm compared to the rural population (t-test; p < 0.001), mostly in younger children and boys. Meanwhile, corneal curvatures were flatter in the urban cohort by 0.08 mm (p < 0.001). This association of axial length with urban vs rural region was reduced in magnitude by 69.7% after accounting for height. CONCLUSIONS: For the same, matched refractive error, children from urban regions had significantly longer eyes and flatter corneal curvature than rural children. Since corneal curvature is defined during the first 2 years of life, early environmental factors may be the source of these differences in ocular dimensions.

19.
Mol Med Rep ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31746394

RESUMO

Depression is often triggered by prolonged exposure to psychosocial stressors and associated with coronary heart disease (CHD). Matrix metalloproteinases (MMPs) are involved in the pathogenesis of various emotional and cardiovascular disorders. The purpose of this study was to investigate whether Kai­Xin­San (KXS), which may terminate the signaling of MMPs, exerts antidepressant­like and cardioprotective effects in a myocardial infarction (MI) plus depression rat model. Rats were randomly assigned to five groups: A normal control (control group), a celisc­injection of isopropyl adrenaline group (ISO group), depression (depression group), an ISO + depression (depression + ISO group), and an ISO + depression group treated with intragastric administration of 1,785 mg/kg KXS (KXS group). Behavioral changes, echocardiography, biochemical index, matrix metalloproteinase (MMP) and apoptosis­related proteins were assessed. Compared with the depression + ISO group, KXS significantly improved stress­induced alterations of behavioral parameters and protected the heart by enlarging the left ventricular (LV) fractional shortening (FS) and LV ejection fraction (EF). Moreover, KXS significantly attenuated ISO + depression­induced MMP­2 and MMP­9 expression at the mRNA and protein level and decreased TIMP in the heart compared to the complex model group. Myocardial apoptosis was significantly attenuated by KXS by regulating the Bcl­2/Bax axis. These results indicated that MI comorbid with depression may damage the MMP balance in the central and peripheral system, and KXS may have a direct anti­depressive and cardio­protective effect by regulating the level of MMPs and associated myocardial apoptosis. It is promising to further explore the clinical potential of KXS for the therapy or prevention of MI plus depression comorbidity disease.

20.
Curr Microbiol ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31720755

RESUMO

Surfactin is a promising microbial lipopeptide with wide applications in food, environmental, agricultural, and pharmaceutical fields. However, its high cost caused by low productivity largely limits the commercial application. In this study, genome shuffling was employed to improve surfactin production in Bacillus velezensis strain LM3403 via recursive protoplast fusion. RT-qPCR analysis was employed to evaluate the transcriptional variance of surfactin synthase genes and surfactin efflux gene to insight into the variance underlying the recombinant strain. After three rounds of genome shuffling, a high-yield and genetic stable recombinant F34 was obtained, exhibiting dramatic improvement in surfactin production (from 229.60 ± 7.10 mg/L to 908.15 ± 5.65 mg/L) with high proportion of long carbon chain homologues. Scale-up fermentation confirmed that F34 had good growth performance and reached the yield of 917.05 ± 10.25 mg/L in a 30 L fermenter, which was 3.99-fold that of the initial strain. RT-qPCR analysis showed that the transcriptional levels of surfactin synthase genes srfAA and sfp, and surfactin efflux gene swrC in F34 were 8.12-fold, 9.27-fold, and 8.45-fold higher than those of LM3403, respectively. The upregulation of genes were consistent with the high surfactin yield in F34, indicating the increased capability of surfactin biosynthesis and transmember efflux in F34. To our knowledge, this is the first attempt to employ genome shuffling to breeding a B. velezensis strain to improve surfactin yield. The research helps us to understand the mechanisms underlying surfactin overproduction and provide references for further rational strain improvement.

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