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Treadmill exercise and mesenchymal stem cell transplantation are both practical and effective methods for the treatment of cerebral ischemia. However, whether there is a synergistic effect between the two remains unclear. In this study, we established rat models of ischemia/reperfusion injury by occlusion of the middle cerebral artery for 2 hours and reperfusion for 24 hours. Rat models were perfused with bone marrow mesenchymal stem cell-derived exosomes (MSC-exos) via the tail vein and underwent 14 successive days of treadmill exercise. Neurological assessment, histopathology, and immunohistochemistry results revealed decreased neuronal apoptosis and cerebral infarct volume, evident synaptic formation and axonal regeneration, and remarkably recovered neurological function in rats subjected to treadmill exercise and MSC-exos treatment. These effects were superior to those in rats subjected to treadmill exercise or MSC-exos treatment alone. Mechanistically, further investigation revealed that the activation of JNK1/c-Jun signaling pathways regulated neuronal apoptosis and synaptic-axonal remodeling. These findings suggest that treadmill exercise may exhibit a synergistic effect with MSC-exos treatment, which may be related to activation of the JNK1/c-Jun signaling pathway. This study provides novel theoretical evidence for the clinical application of treadmill exercise combined with MSC-exos treatment for ischemic cerebrovascular disease.
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Cardiovascular disease (CVD) is an important factor threatening the health of the elderly. Aging leads to changes in the structure and function of the cardiovascular system, which increases the risk of CVD in the elderly. Cardiac aging is characterized by increased left ventricular wall thickness, increased degree of myocardial fibrosis, increased cardiac hardness, and decreased cardiac function, while vascular aging is characterized by enlarged lumen, thickened wall, and endothelial dysfunction. Promoting healthy cardiovascular aging means reducing the age-related cardiovascular dysfunction and the risks of CVD. Exercise is a crucial means for the treatment and rehabilitation of CVD. Exercise reduces the risk factors of CVD, remodels the cardiovascular structure, and increases the resistance of heart to detrimental stimulus, which promotes healthy cardiovascular aging. The improved mitochondrial function via exercise plays a key role in the health effects of exercise. In addition, exercise promotes the secretion of exerkines in various tissues and organs, which plays a role in reducing inflammation, improving metabolism, inhibiting apoptosis, etc., thus benefiting cardiovascular health. This review discusses the mechanism and potential application of exercise in promoting healthy cardiovascular aging. Exploring the specific mechanisms underlying exercise-induced cardiovascular health and formulating accurate exercise prescriptions for different populations is an important direction to promote healthy cardiovascular aging and prevent CVD.
Subject(s)
Humans , Aged , Heart , Exercise , Aging , Cardiovascular Diseases/prevention & control , Risk FactorsABSTRACT
Objective To investigate the relationship between body composition and serum lipids and uric acid among adults in Maonan, and to analyze the effect of body composition changes on blood lipid and uric acid. Methods Totally 584 Maonan adult volunteers in Maonan village of Maonan Autonomous County in Guangxi, the age from 20 to 80 were recruited. The height was measured by the personal height tester; the body composition was measured by the ANITAMC-180 instrument; and the blood lipids and blood uric acid were measured by the Hitachi 7600 instrument. The obtained data were statistically analyzed by SPSS 20. 0. Results The age,height, weight, free fat mass, muscle mass, presumptive bone mass, body water, proptein,extracellular water, intracellular water, and waist-to-hip ratio were greater in Maonan men than in women (P<0. 05). However, whereas male fat content, body fat rate, and subcutaneous fat content were smaller than those of female (P < 0. 01). The total prevalence of hyperuricemia and hyperlipidemia in Maonan nationality was 13. 9% and 28. 4%, respectively. The prevalence of hyperuricemia and hyperlipidemia in males was higher than in females. In males, the body mass, body mass index, free fat mass, fat mass, muscle mass, presumptive bone mass, protein, extracellular water, body fat rate, visceral fat content, subcutaneous fat content and waist-hip ratio of the hyperlipidemia group were higher than the normal group (P<0. 05); and in females, the age, body mass index, fat mass, body fat rate, visceral fat content and waist-hip ratio of the hyperlipidemia group were higher than the normal group. In male, The body mass, free fat mass, presumptive bone mass, body water, extracellular water of the hyperuricemia group were higher than the normal group (P<0. 05); In females, the age, body mass, body mass index, fat mass, extracellular water, body fat ratio, muscle mass, visceral fat content, subcutaneous fat content, and waist-hip ratio of the hyperuricemia group were higher than the normal group. Conclusion The detection rate of hyperlipidemia and hyperuricemia in males of Guangxi Maonan nationality is all higher than that in females. The body composition is significant differences between the normal adults and the patients with hyperlipidemia and hyperuricemia of Maonan nationality in Guangxi.
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Sialic acid binding immunoglobulin type lectin-15 (Siglec-15), one of the Siglec gene family members, is a new immunosuppressive molecule. Siglec-15 is highly expressed in a variety of human tumor cells and tumor-associated macrophages, but the biological function of Siglec-15 in colorectal cancer (CRC) and its effect on the tumor immune microenvironment remains poorly understood. This study aimed to investigate the effects of aberrant expression of Siglec-15 on the biological behaviors of CRC cells and the infiltration of CD4
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CXC chemokine ligand 8 (CXCL8) is highly expressed in many human tumors including colorectal cancer, and it can promote the malignant progression of tumors. It was reported that M2 macrophages were abundant in colorectal cancer microenvironment, but whether CXCL8 affects the infiltration of M2 macrophages and its potential mechanism are not yet clear. The study aimed to investigate the effect of CXCL8 on M2 macrophage infiltration and chemotaxis in the colorectal cancer. Firstly, we analyzed the CXCL8 expression and immune cell infiltration in human colorectal cancer tissues from TCGA RNA-seq data. The expression of CXCL8 was verified by immunohistochemistry in tissues obtained from Shanxi Provincial Cancer Hospital. Then, Western blot and qRT-PCR were employed to detect CXCL8 expression in five colorectal cancer cell lines. THP-1 cells were allowed to differentiate into M2 macrophages via the phorbol myristate acetate (PMA) and IL-4 treatment, followed by detection of the chemotaxis of M2 macrophages towards HCT116, SW480 and CXCL8-HCT116, CXCL8-SW480 cell lines. HCT116 and SW480 cells were treated with interleukin 1β (IL-1β) to detect the expression of CXCL8, and co-cultured with M2 macrophages to analyze the chemotactic activity. The results revealed that the expression of CXCL8 was increased in pairs of CRC tissues versus normal adjacent tissues, and there were more M2 macrophage infiltration in cancer tissues with high expression of CXCL8. The mRNA and protein expression of CXCL8 in HCT116 and SW480 were increased after the IL-1β treatment (P < 0. 05). We confirmed that CXCL8 is a chemotactic factor for M2 macrophages by transwell assays (P<0. 05). In conclusion, CXCL8 in colorectal cancer cells can be induced by IL-1β in colorectal cancer cells and the upregulation of CXCL8 can promote the chemotaxis of M2 macrophages. The massive infiltration of M2 macrophages in colorectal cancer microenvironment may be related with the increased expression of CXCL8.
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Objective:To compare the efficacy of posterior atlas uniaxial and polyaxial screw instrumentation and fusion with bone graft for Gehweiler type IIIb atlas fracture.Methods:A retrospective cohort study was performed to analyze the clinical data of 36 patients with Gehweiler type IIIb atlas fracture admitted to Henan Provincial People′s Hospital from January 2015 to October 2020. There were 29 males and 7 females, with age range of 23-82 years [(48.8±15.5)years]. All patients were treated with posterior atlas screw-rod internal fixation and fusion with bone graft, of which 14 received atlas uniaxial screw internal fixation (uniaxial screw group) and 22 received atlas polyaxial screw internal fixation (polyaxial screw group). The operation time and intraoperative blood loss were compared between the two groups. The atlas fracture union rate and atlantoaxial posterior arch bone fusion rate were compared between the two groups at 3 months and 6 months after operation. The anterior atlantodental interval (ADI), basion-dens interval (BDI) and lateral mass displacement (LMD) were compared between the two groups to evaluate the reduction of fracture fragments before operation, at 1, 3, 6 months after operation and at the last follow-up. At the same time, the visual analogue scale (VAS) and neck dysfunction index (NDI) were compared between the two groups to evaluate neck pain and functional recovery. The postoperative complications were observed.Results:All patients were followed up for 12-44 months [(27.2±9.9)months]. There was no significant difference in operation time or intraoperative blood loss between the two groups (all P>0.05). The atlas fracture union rate and atlantoaxial posterior arch bone fusion rate were 85.7% (12/14) and 78.6% (11/14) in uniaxial screw group at 3 months after operation, insignificantly different from those in polyaxial screw group [72.7% (16/22) and 77.3% (17/22)] (all P>0.05). All patients in the two groups achieved bone union and fusion at 6 months after operation. There was no significant difference in ADI between the two groups before and after operation (all P>0.05). The BDI in the two groups did not differ significantly before operation ( P>0.05), but a significantly higher value was found in uniaxial screw group at 1, 3, and 6 months after operation and at the last follow-up [(5.9±1.3)mm, (5.8±1.3)mm, (5.9±1.2)mm and (5.8±1.2)mm] than in polyaxial screw group [(3.1±0.6)mm, (3.1±0.6)mm, (3.1±0.6)mm and (3.1±0.6)mm] (all P<0.01). The two groups did not differ significantly before operation ( P>0.05), but LMD at 1, 3, and 6 months after operation and at the last follow-up was (1.6±0.8)mm, (1.5±0.8)mm, (1.5±0.7)mm and (1.5±0.9)mm in uniaxial screw group, significantly lower than that in polyaxial screw group [(4.8±1.6)mm, (4.6±1.6)mm, (4.9±1.6)mm and (4.9±1.6)mm] (all P<0.01). There was no significant difference in VAS between the two groups before operation ( P>0.05). The VAS at 1, 3, and 6 months after operation and at the last follow-up was 3.0(3.0, 4.0)points, 2.0(1.0, 2.0)points, 1.0(0.8, 2.0)points and 1.0(0.0, 1.3)points in uniaxial screw group and was 3.5(3.0, 4.0)points, 2.0(2.0, 3.0)points, 2.0(1.0, 2.0)points and 2.0(1.0, 3.0)points in polyaxial screw group. In comparison, the VAS scored much lower in uniaxial screw group than in polyaxial screw group at 6 months after operation and at the last follow-up (all P<0.01). There was no significant difference in NDI between the two groups before operation ( P>0.05). The NDI at 1, 3, and 6 months after operation and at the last follow-up was 34.9±6.3, 23.4±6.2, 13.9±2.7 and 9.4±2.8 in uniaxial screw group and was 33.2±6.1, 24.4±6.3, 18.1±4.1 and 12.7±3.2 in polyaxial screw group, showing a significantly lower NDI in uniaxial screw group than in polyaxial screw group at 6 months after operation and at the last follow-up (all P<0.01). The complication rate was 21.4% (3/14) in uniaxial screw group when compared to 22.7% (5/22) in polyaxial screw group ( P>0.05). Conclusion:For Gehweiler type IIIb atlas fracture, both techniques can attain atlas fracture union and atlantoaxial posterior arch bone fusion, but the posterior atlas uniaxial screw instrumentation and fusion is superior in reduction of atlas fracture displacement and lateral mass separation, neck pain relief and functional improvement.
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Objective:To observe the effect of insertion of in-out-in axis pedicle screws on the vertebral artery in the posterior occipitocervical surgery for atlantoaxial subluxation or instability.Methods:The data of 52 patients with atlantoaxial dislocation or instability were analyzed who had been treated by internal fixation with in-out-in pedicle screws in the posterior occipitocervical surgery from January 2015 to February 2021 at Department of Spine and Spinal Cord Surgery, Henan Provincial People's Hospital. There were 30 males and 22 females, aged from 17 to 65 years (mean, 41.2 years). There were 26 cases of unilateral vertebral artery high-riding, 3 cases of bilateral high-riding, 19 cases of unilateral narrow pedicle due to C2 and C3 fusion, and 4 cases of bilateral narrow pedicles. X-ray, CTA and MRI were performed before and 3 days after surgery. The patients' clinical symptoms were recorded. CTA was used to measure the diameter of the vertebral artery at the transverse foramina of C 2 and C 3 and to observe the effect of in-out-in screws on the morphology of the vertebral artery. X-ray and CT examinations were performed at 6 months after surgery to observe the bone fusion. Results:The surgery went on uneventfully in all the patients. In the 9 cases undergoing anterior and posterior surgery, the operation time averaged 271.2 min (from 213 to 352 min) and the bleeding volume 471.5 mL (from 230 to 830 mL). In the 43 cases undergoing posterior surgery, the operation time averaged 171.6 min (from 131 to 226 min) and the bleeding volume 395.9 mL (from 170 to 660 mL). There was no such complication as spinal or vascular injury. The CTA reexamination 3 days after surgery showed that the diameter of the vertebral artery was (2.92±0.55) mm and (3.04±0.54) mm, respectively at the cervical 2 and 3 transverse foramina, showing no significant change compared with the preoperative values [(2.91±0.68) mm and (3.11±0.50) mm] ( P>0.05) and that the vertebral artery was displaced externally and inferiorly in 21 cases. Follow-ups for all patients ranged from 7 to 24 months (mean, 11 months). At 6 months after surgery, bone fusion was observed by imaging and no breakage or displacement of the internal fixation was observed. Conclusion:The in-out-in pedicle screws in the posterior occipitocervical surgery may have little impact on the vertebral artery, leading to reliable clinical outcomes.
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Bifidobacteria are among the first colonizers of the human gastrointestinal tract. Different bacterial species use different mechanisms for utilization of various carbon sources in order to establish themselves in the complex microbial ecosystem of the gut. However, these mechanisms still need to be explored. Here, a large gene-phenotype correlation analysis was carried out to explore the metabolic and genetic diversity of bifidobacterial carbohydrate utilization abilities. In this study, we used 21 different carbohydrates to determine the growth phenotypes, the distribution of glycoside hydrolases (GHs), and gene clusters related to the utilization of multiple carbon sources in six human-residential Bifidobacterium species. Five carbohydrates significantly stimulated growth of almost all strains, while the remaining sugars exhibited species- and strain-specificity. Correspondingly, different Bifidobacterium species also had specific GHs involved in fermentation of plant or host glycans. Moreover, we analyzed several carbohydrate utilization gene clusters, such as 2-fucosyllactose (2'FL), sialic acid (SA), and fructooligosaccharide (FOS). In summary, by using 217 bifidobacterial strains and a wide range of growth substrates, our research revealed inter- and intra-species differences in bifidobacterial in terms of carbohydrate utilization. The findings of this study are useful for the process of developing prebiotics for optimum growth of probiotics, especially Bifidobacterium species.
ABSTRACT
Fermented dairy products have been recognized as the best carriers for the administration of probiotics. Because one of the potential probiotic strains, Lactobacillus plantarum, has poor proteolytic ability and weak acidifying capacity in milk fermentation, the aim of this study was to preliminarily investigate the stimulation effect of plant-based meals on L. plantarum CCFM8661 growth in milk, and subsequently develop a yogurt or yogurt drinks containing probiotic strain L. plantarum CCFM8661. Milk supplemented with different concentrations (5 to 10%, wt/wt) of oat extract and malt extract, inoculated with 2.5 × 107 cfu/mL of L. plantarum CCFM8661, and then incubated at 35°C. The pH value, titration acidity, and viable cell counts during 48-h fermentation at 35°C and 25-d storage at 4°C, were determined at different intervals. The results showed that the promotion effects of oat extract and malt extract on L. plantarum CCFM8661 growth rate in milk were much stronger than almond, walnut, sweet corn, peanut, and soybean meals. In addition, the stimulation effect of oat extract was associated with its concentration, and was much stronger than that of malt extract. Furthermore, viable counts and titration acidity of yogurt were gradually increased in the oat extract group, whereas viable counts were gradually decreased and titration acidity were slightly increased in the malt extract group during the 25-d storage at 4°C.
Subject(s)
Lactobacillus plantarum/growth & development , Milk/microbiology , Plant Extracts/pharmacology , Animals , Avena , Cultured Milk Products/microbiology , Fermentation , Hordeum , Hydrogen-Ion Concentration , Lactobacillus plantarum/drug effects , Lactobacillus plantarum/metabolism , Probiotics , YogurtABSTRACT
The microbiome associated with brown planthopper (BPH) plays an important role in mediating host health and fitness. Characterization of the microbial community and its structure is prerequisite for understanding the intricate symbiotic relationships between microbes and host insect. Here, we investigated the bacterial and fungal communities of BPH at different developmental stages using high-throughput amplicon sequencing. Our results revealed that both the bacterial and fungal communities were diverse and dynamic during BPH development. The bacterial communities were generally richer than fungi in each developmental stage. At 97% similarly, 19 phyla and 278 genera of bacteria were annotated, while five fungal phyla comprising 80 genera were assigned. The highest species richness for the bacterial communities was detected in the nymphal stage. The taxonomic diversity of the fungal communities in female adults was generally at a relatively higher level when compared to other developmental stages. The most dominant phylum of bacteria and fungi at each developmental stage all belonged to Proteobacteria and Ascomycota, respectively. A significantly lower abundance of bacterial genus Acinetobacter was recorded in the egg stage when compared to other developmental stages, while the dominant fungal genus Wallemia was more abundant in the nymph and adult stages than in the egg stage. Additionally, the microbial composition differed between male and female adults, suggesting that the microbial communities in BPH were gender-dependent. Overall, our study enriches our knowledge on the microbial communities associated with BPH and will provide clues to develop potential biocontrol techniques against this rice pest.
Subject(s)
Bacteria/isolation & purification , Fungi/isolation & purification , Hemiptera/microbiology , Microbiota , Animals , Bacteria/classification , Female , Fungi/classification , Hemiptera/growth & development , High-Throughput Nucleotide Sequencing , Male , Nymph/growth & development , Nymph/microbiology , Ovum/growth & development , Ovum/microbiology , SymbiosisABSTRACT
Ladybird beetles (Coleoptera: Coccinellidae), with broad morphological diversity, wide geographic distribution and substantial agricultural significance, are a challenging group for taxonomists and phylogenetics. As a promising tool to identify and discover new species, DNA barcoding might offer significant potential for identification, taxonomy and phylogeny of ladybird beetles. In the present study, a total of 1364 COI (cytochrome C oxidase subunit I) sequences representing 128 species from 52 genera of ladybird beetles were screened for barcoding evaluation and phylogenetic analysis. Our results from the barcoding analysis revealed that COI displays a similar level of species identification efficiency (nearly 90%) either based on Kimura two-parameter (K2P) distances calculation or on simplified neighbour-joining (NJ) tree construction. The phylogenetic relationships within the family Coccinellidae was analyzed by Bayesian-inference (BI) method. The phylogenetic results confirmed the monophyly of the subfamilies Microweisinae and Coccinellinae sensu Slipinski (2007), and suggested that the subfamilies Coccidulinae, Chilocorinae and Scymninae are paraphyletic. However, the phylogenetic relationships among different subfamilies are not clearly defined and thus remain to be thoroughly studied. Overall, our study confirmed the usefulness of DNA barcoding for coccinellid species identification and phylogenetic inference.
Subject(s)
Coleoptera/genetics , Phylogeny , Animals , Coleoptera/classification , DNA Barcoding, Taxonomic/methods , DNA Barcoding, Taxonomic/standards , Electron Transport Complex IV/genetics , Insect Proteins/geneticsABSTRACT
Mitochondrial genomes are widely used for phylogenetic and phylogeographic analyses among arthropods, but there is a lack of sufficient mitochondrial genome sequence data for spiders. Herein, we sequenced and characterized the complete mitochondrial genome of a crab spider Ebrechtella tricuspidata (Araneae: Thomisidae). The circular mitochondrial genome is 14,352â¯bp long, including a standard set of 37 genes and an Aâ¯+â¯T-rich region. Nucleotide composition is highly biased toward Aâ¯+â¯T nucleotides (77.3%). A novel gene order rearrangement is detected by a tRNA (trnL1) translocation. Tandem repeats are not identified in the Aâ¯+â¯T-rich region. Most of the tRNAs are greatly reduced in size and cannot be folded into typical cloverleaf-shaped secondary structures. The phylogenetic analysis confirms that the mitochondrial genome sequences are useful in resolving higher-level relationship of Araneae. Overall, our data present in this study will elevate our knowledge on the architecture and evolution of spider mitochondrial genome.
Subject(s)
Genome, Mitochondrial , RNA, Transfer/genetics , Spiders/genetics , Animals , Arthropod Proteins/genetics , Evolution, Molecular , Phylogeny , RNA, Ribosomal/genetics , Spiders/classificationABSTRACT
During heating, there are a lot of physical and chemical changes in milk components, which are mainly reflected in the changes of proteins. Calcium ions in milk react with proteins to precipitate or form gels, and the thermal stability of milk is affected by the type and content of calcium. In this study, different calcium-fortified milk systems were treated by rapid conventional heating (RCV) and microwave heating (MV) to evaluate the effects of forms and concentration of calcium in liquid milk on microwave absorption properties and thermal stability of milk. It was found that the concentration of calcium ions on microwave energy absorption is not a significant influence, while the forms affected the systems dramatically. The thermal stability of milk during MV is remarkably affected by the forms of calcium ions. When adding ionized calcium, the calcium-fortified milk systems had poor thermal stability and severe agglomeration of protein, while the addition of milk calcium had little effect and was almost free from protein coagulation. It could be speculated that the metal ions in the microwave field could create a strong vibration that could trigger protein agglomeration through the combination of the surrounding casein phosphorylates.
Subject(s)
Calcium/analysis , Microwaves , Milk/chemistry , Absorption, Radiation , Animals , Hot Temperature , Milk/radiation effects , Milk/standards , Milk Proteins/chemistry , Protein StabilityABSTRACT
In this study, the binding of cyanidin-3-O-glucoside (C3G) to preheated milk proteins ß-lactoglobulin (ß-Lg) and ß-casein (ß-CN) at 55-90⯰C under pHâ¯3.6 and pHâ¯6.3 was investigated using multi-spectral techniques. Fluorescence quenching spectroscopy data showed C3G quenched milk proteins' fluorescence strongly. Thermodynamic analysis revealed that C3G bound to ß-Lg mainly through hydrogen bonding and hydrophobic interactions, and that their binding affinity increased gradually with increasing preheating temperature at pHâ¯6.3, whereas it decreased at pHâ¯3.6. Hydrogen bonding and van der Waals forces played the major roles in the interaction of ß-CN with C3G, their affinity decreasing with increasing preheating temperature at both pH values. The combination of C3G and preheated ß-Lg at 85⯰C had the strongest binding affinity, with a KA of 14.10 (±0.33)â¯×â¯105â¯M-1 (pHâ¯6.3, 298â¯K). Preheating of milk proteins did not change their major forces with C3G. Fourier transform infrared spectra (FT-IR) results showed that C3G binding altered the secondary structures of ß-Lg and ß-CN by reducing the proportion of α-helix and ß-sheet structures and increasing the proportion of random coil and turn structures. The structural changes of preheated ß-Lg upon C3G binding were more pronounced than that of native ß-Lg, while there was little difference between preheated and native ß-CN in their structural changes upon C3G binding. These results will be helpful in better understanding the relevance of native and preheated milk protein-C3G interactions to the stability of C3G, and in promoting its application in the food industry as a natural pigment.
Subject(s)
Anthocyanins/metabolism , Food Handling/methods , Glucosides/metabolism , Milk Proteins/metabolism , Fluorescence , Hot Temperature , Hydrogen Bonding , Hydrogen-Ion ConcentrationABSTRACT
Glucansucrases (GSs) in glycoside hydrolase family 70 (GH70) catalyze the synthesis of α-glucans from sucrose, a reaction that is widely seen in lactic acid bacteria (LAB). These enzymes have been implicated in many aspects of microbial life. Products of GSs have great commercial value as food supplements and medical materials; therefore, these enzymes have attracted much attention from both science and industry. Certain issues concerning the origin and evolution of GSs are still to be addressed, although an increasing number of GH70 enzymes have been characterized. This study describes a GS enzyme with the appearance of a branching sucrase (BrS). Structural analysis indicated that this GS enzyme produced a type of glucan composed of an α-(1â6) glucosidic backbone and α-(1â4) branches, as well as a considerable amount of α-(1â3) branches, distinguishing it from the GSs identified so far. Moreover, sequence-based analysis of the catalytic core of this enzyme suggested that it might be an evolutionary intermediate between the BrS and GS subgroups. These results provide an evolutionary link between these subgroups of GH70 enzymes and shed new light on the origination of GSs.IMPORTANCE GH70 GSs catalyze the synthesis of α-glucans from sucrose, a reaction that is widely seen in LAB. Products of these enzymes have great commercial value as food supplements and medical materials. Moreover, these enzymes have attracted much attention from scientists because they have potential in tailored synthesis of α-glucans with desired structures and properties. Although more and more GSs have been characterized, the origin and evolution of these enzymes have not been well addressed. This study describes a GS with the appearance of a BrS (i.e., high levels of similarity to BrSs in sequence analysis). Further analysis indicated that this enzyme synthesized a type of insoluble glucan composed of an α-(1â6) glucosidic backbone and many α-(1â4)- and α-(1â3)-linked branches, the linkage composition of which has rarely been reported in the literature. This BrS-like GS enzyme might be an evolutionary intermediate between BrS and GS enzymes.
Subject(s)
Bacterial Proteins/genetics , Glycosyltransferases/genetics , Leuconostoc mesenteroides/genetics , Amino Acid Sequence , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Glycoside Hydrolases/chemistry , Glycoside Hydrolases/genetics , Glycoside Hydrolases/metabolism , Glycosyltransferases/chemistry , Glycosyltransferases/metabolism , Leuconostoc mesenteroides/metabolism , Phylogeny , Sequence Alignment , Sucrase/chemistry , Sucrase/genetics , Sucrase/metabolismABSTRACT
For the industrial production of probiotics powder, various sugars have been used as cryoprotectants to preserve probiotics during freeze-drying. Some of these sugars can be metabolized by Lactobacillus with the production of acids during the mix. In this study, we investigated the effect of acids on ATPase, ß-galactosidase, lactate dehydrogenase (LDH), integrity and fluidity of cell membrane and the survival rate of Lactobacillus during freeze-drying. In the presence of Lactobacillus, acids were produced from cryoprotectants containing fermentable sugars before freezing, resulting in a decrease in the pH of the bacterial suspension to below 5.0. During freeze-drying, the acids caused a loss of viability of Lactobacillus due to aggravated damage to ATPase, ß-galactosidase and cell membrane fluidity, but not LDH and cell membrane integrity. This finding implied that cryoprotectants that do not lead to the production of acids are effective in improving the survival rate of freeze-dried Lactobacillus. Here, a new formula was proposed for a protectant containing whey protein isolate (WPI) and rhamnose, which were not metabolized. In addition, linear-regression analyses were performed on the proportion of cryoprotectants (M) against cell paste (m), total cell count (N), total surface area (St) and total volume (Vt) of bacteria for 100% survival rate. The total surface areas of bacteria were found to be highly correlated with the amount of proposed cryoprotectant. The following prediction equation was established for the optimal initial cell concentration for a 100% survival rate of freeze-dried Lactobacillus: N (4πr2+2πl)=(0.66±0.03)M.
Subject(s)
Acids/pharmacology , Carbohydrate Metabolism/drug effects , Cryoprotective Agents/pharmacology , Lactobacillus/drug effects , Lactobacillus/metabolism , Microbial Viability/drug effects , Preservation, Biological , Acids/metabolism , Bacterial Load/standards , Cell Membrane/drug effects , Cryoprotective Agents/chemistry , Fermentation , Freeze Drying/standards , Lactobacillus/cytology , Preservation, Biological/methods , Preservation, Biological/standards , Probiotics/standardsABSTRACT
The proteinase with milk-clotting activity (MCA) from Paenibacillus spp. BD3526 is characterized as a neutral metalloproteinase of 35kDa. However, the rapid reduction of its MCA during separation and purification leads to low enzyme recovery. The effects of metal ions, inactivation kinetics, and concentration of calcium on the enzymatic activities and thermal stability of the BD3526 metalloproteinase were investigated. In the absence of calcium, the residual activities of the BD3526 metalloproteinase sharply declined during the first three hours, and continued to slowly decrease thereafter. The activities were well fitted by a double-exponential decay model. The inactivation rates were significantly inhibited by calcium and the residual enzyme activities were maintained at more than 80% for 30d at room temperature with 50-100mM calcium. An intermolecular autoproteolytic mechanism was responsible for BD3526 metalloproteinase inactivation. The target protein band with MCA remained largely undegraded in the enzyme solution that was supplemented with 100mM of calcium, but gradually diminished over time in the absence of calcium. N-terminal amino acid sequencing showed that cleavage at the His252-Ala253 peptide bond facilitated the conversion of the zymogen into the active enzyme. Sequence alignment revealed the presence of two highly conserved motifs, HEXXH and GXXNEXXSD, indicating that the enzyme belonged to the metalloproteinase family M4, also known as thermolysin-like proteinases (TLPs). Further structural analysis showed that the observed calcium-dependent stability of the BD3526 TLP may be attributable to a partly degenerated calcium-binding site, Ca1-2, and a mutant calcium-binding site, Ca3.
Subject(s)
Bacterial Proteins/chemistry , Calcium/chemistry , Metalloproteases/chemistry , Milk/microbiology , Models, Statistical , Paenibacillus/chemistry , Amino Acid Sequence , Animals , Bacterial Proteins/isolation & purification , Catalytic Domain , Cattle , Enzyme Stability , Female , Inactivation, Metabolic , Kinetics , Metalloproteases/isolation & purification , Milk/chemistry , Models, Molecular , Paenibacillus/enzymology , Protein Binding , Sequence Alignment , Structural Homology, Protein , Time FactorsABSTRACT
Objective To explore the breakthrough points of pharmaceutical care by clinical pharmacists for patients with heat stroke .Methods Clinical pharmacists participated in the treatment of patients with heat stroke ,focused on the key points of effective treatment of heat stroke ,and put forward some suggestions for reasonable drug use from the aspects of active brain protection ,correction of coagulation disorders ,protection of multiple organ function and effective infection control .Results The potential drug side effects were minimized ,the medication safety and the therapeutic outcome were optimized .Conclusion Clinical pharmacists improved clinical rational drug use by actively participating in the treatment of heat stroke with drug therapy .
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Objective The correlation and agreement of mycophenolic acid (MPA) plasma concentrations that detected by enzyme extended immunoassay (EMIT) and high performance liquid chromatography (HPLC) were studied using Pearson's correlation and Bland-Altman plots.METHODS 435 plasma samples were collected from 95 renal transplant patients who were treated with MPA from October 2014 to December 2015.The MPA plasma concentrations were simultaneously measured by EMIT and HPLC respectively,and the results were divided into two levels.Paired t test and Pearson's correlation were performed using SPSS13.0 to evaluate the relationships between the results in each level.The Bland-Altman plot was used to assess the agreement of the results of two methods.Results Higher concentrations were obtained with EMIT,there was a significant positive bias of EMIT for MPA(20.94% ±14.42 %,P<0.001).Pearson's correlation analysis and Bland-Altman analysis showed that the results from different methods presented good correlation (r>0.98) and agreement.Conclusion The results of EMIT were higher than that of HPLC.There were good correlation and agreement between the two methods.The differences between EMIT and HPLC suggest that different therapeutic window should be set up when the two methods are used for MPA therapeutic drug monitoring.
ABSTRACT
Strain BD3526T, isolated from raw yak milk collected in Tibet, China, was studied to determine its taxonomic status. The strain was Gram-reaction positive, motile, catalase-positive, aerobic or facultatively anaerobic. The DNA G+C content of the strain was 47.5âmol% and its peptidoglycan contained meso-diaminopimelic acid. The predominant menaquinone was MK-7. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and C16 : 0. Based on 16S rRNA gene sequence analysis, similarities among strain BD3526T and its most closely related species, Paenibacillus shenyangensis A9T, 'Paenibacillus dauci' H9, 'Paenibacillus wulumuqiensis' Y24 and Paenibacillus hunanensis DSM 22170T were 99.0, 98.5, 97.3 and 96.7 %, respectively. Levels of DNA-DNA relatedness among strain BD3526T and P. hunanensis DSM 22170T and Paenibacillus polymyxa ATCC 842T ( = DSM 36T), the type species of the genus, were 41.2 and 45.6 %, respectively. In silico genome-to-genome comparison showed that the DNA-DNA hybridization values among strain BD3526T and P. shenyangensis A9T, 'P. dauci' H9 and 'P. wulumuqiensis' Y24 were lower than 70 %. Based on its molecular and physiological properties, strain BD3526T ( = DSM 28815T = CGMCC 8333T) is identified as the type strain of a novel species within the genus Paenibacillus, for which the name Paenibacillus bovis is proposed.