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1.
The presence of yeast cells could stimulate hydrogen utilization of acetogens and enhance acetogenesis. To understand the roles of acetogens in rumen fermentation, an in vitro rumen fermentation experiment was conducted with addition of acetogen strain (TWA4) and/or Saccharomyces cerevisiae fermentation product (XP). A 2×2 factorial design with two levels of TWA4 (0 or 2×107 cells/ml) and XP (0 or 2 g/L) was performed. Volatile fatty acids (VFAs) were increased (P<0.05) in XP and TWA4XP, while methane was increased only in TWA4XP (P<0.05). The increase rate of microorganisms with formyltetrahydrofolate synthetase, especially acetogens, was higher than that of methanogens under all treatments. Lachnospiraceae was predominant in all acetogen communities, but without close acetyl-CoA synthase (ACS) amino acid sequences from cultured isolates. Low-Acetitomaculum ruminis-like ACS was predominant in all acetogen communities, while four unique phylotypes in XP treatment were all amino acid identified low-Eubacterium limosum-like acetogens. It differs to XP treatment that more low-A. ruminis-like and less low-E. limosum-like sequences were identified in TWA4 and TWA4XP treatments. Enhancing acetogenesis by supplementation with an acetogen strain and/or yeast cells may be an approach to mitigate methane, by targeting proper acetogens such as uncultured low-E. limosum-like acetogens.  相似文献   

2.
In this study, we isolated an environmental clone of Ochrobactrum intermedium, strain 2745-2, from the formation water of Changqing oilfield in Shanxi, China, which can degrade crude oil. Strain 2745-2 is aerobic and rod-shaped with optimum growth at 42 °C and pH 5.5. We sequenced the genome and found a single chromosome of 4 800 175 bp, with a G+C content of 57.63%. Sixty RNAs and 4737 protein-coding genes were identified: many of the genes are responsible for the degradation, emulsification, and metabolizing of crude oil. A comparative genomic analysis with related clinical strains (M86, 229E, and LMG3301T) showed that genes involved in virulence, disease, defense, phages, prophages, transposable elements, plasmids, and antibiotic resistance are also present in strain 2745-2.  相似文献   

3.
Objective: To investigate the protective effects and mechanisms of action of dexamethasone and Salvia miltiorrhiza on multiple organs in rats with severe acute pancreatitis (SAP). Methods: The rats were divided into sham-operated, model control, dexamethasone treated, and Salvia miltiorrhiza treated groups. At 3, 6, and 12 h after operation, the mortality rate of different groups, pathological changes, Bcl-2-associated X protein (Bax) and nuclear factor-κB (NF-κB) protein expression levels in multiple organs (the pancreas, liver, kidneys, and lungs), toll-like receptor 4 (TLR-4) protein levels (only in the liver), intercellular adhesion molecule 1 (ICAM-1) protein levels (only in the lung), and terminal deoxynucleotidy transferase mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) staining expression levels, as well as the serum contents of amylase, glutamate-pyruvate transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), blood urea nitrogen (BUN), and creatinine (CREA) were observed. Results: The mortality rate of the dexamethasone treated group was significantly lower than that of the model control group (P<0.05). The pathological changes in multiple organs in the two treated groups were relieved to different degrees (P<0.05 and P<0.01, respectively), the expression levels of Bax and NF-κB proteins, and apoptotic indexes of multiple organs were reduced (P<0.05 and P<0.01, respectively). The contents of amylase, GPT, GOT, BUN, and CREA in the two treated groups were significantly lower than those in model control groups (P<0.05 and P<0.01, respectively). The expression level of ICAM-1 protein in the lungs (at 3 and 12 h) in the dexamethasone treated group was significantly lower than that in the Salvia miltiorrhiza treated group (P<0.05). The serum contents of CREA (at 12 h) and BUN (at 6 h) of the Salvia miltiorrhiza treated group were significantly lower than those in the dexamethasone treated group (P<0.05). Conclusions: Both dexamethasone and Salvia miltiorrhiza can reduce the inflammatory reaction, regulate apoptosis, and thus protect multiple organs of rats with SAP.  相似文献   

4.
In the present study, we investigated the possible toxicity mechanism of lipopolysaccharide (LPS) extracted from Gram-negative bacteria in Eriocheir sinensis hemocytes. Apoptotic hemocytes and reactive oxygen species (ROS) production induced by the LPS were monitored by the combination of flow cytometry and microscope observation. It was shown that LPS induced serious damage on the DNA and morphological changes in hemocytes, including cell shrinkage, fracture of nucleus membrane, margination, condensation and fragmentation of chromatin, and formation of apoptotic bodies indicating obvious hemocyte apoptosis. As compared with the control group, the apoptotic cell ratio increased to 30.61% and 39.01% after 1-h exposure and 57.72% and 75.01% after 2-h exposure to 1 and 10 μg/ml LPS, respectively (P<0.05). Significant outburst of ROS production was observed in LPS-treated hemocytes with approximately 176.6% of relative dichlorofluorescein mean fluorescence at 1-h exposure, followed by a drastic decline (P<0.05). These results indicated that LPS would induce oxidative stress on hemocytes from E. sinensis and cause ROS burst, DNA damage, and subsequently apoptosis. The process of ROS-mediated apoptosis might be one of the potential toxicity mechanisms of LPS on crustacean hemocytes.  相似文献   

5.
Objective: To compare the peri-operative outcomes for laparoscopic distal pancreatectomy (LDP) and open distal pancreatectomy (ODP) for benign or premalignant pancreatic neoplasms in two institutions. Methods: This prospective comparative study included 91 consecutive patients who underwent LDP (n=45) or ODP (n=46) from Jan. 2010 to Dec. 2012. Demographics, intra-operative characteristics, and post-operative outcomes were compared. Results: The median operating time in the LDP group was (158.7±38.3) min compared with (92.2±24.1) min in the ODP group (P<0.001). Patients had lower blood loss in LDP than in the ODP (122.6±61.1) ml vs. (203.1±84.8) ml, P<0.001). The rates of splenic conservation between the LDP and ODP groups were similar (53.3% vs. 47.8%, P=0.35). All spleen-preserving distal pancreatectomies were conducted with vessel preservation. LDP also demonstrated better post-operative outcomes. The time to oral intake and normal daily activities was faster in the LDP group than in the ODP group (1.6±0.5) d vs. (3.2±0.7) d, P<0.01; (1.8±0.4) d vs. (2.1±0.6) d, P=0.02, respectively), and the postoperative length of hospital stay in LDP was shorter than that in ODP (7.9±3.8) d vs. (11.9±5.8) d, P=0.006). No difference in tumor size (4.7±3.2) cm vs. (4.5±1.8) cm, P=0.77) or overall pancreatic fistula rate (15.6% vs. 19.6%, P=0.62) was found between the groups, while the overall post-operative complication rate was lower in the LDP group (26.7% vs. 47.8%, P=0.04). Conclusions: LDP is safe and effective for benign or premalignant pancreatic neoplasms, featuring lower blood loss and substantially faster recovery.  相似文献   

6.
The metabolic activity of organisms can be measured by recording the heat output using microcalorimetry. In this paper, the total alkaloids in the traditional Chinese medicine Radix Aconiti Lateralis were extracted and applied to Escherichia coli and Staphylococcus aureus. The effect of alkaloids on bacteria growth was studied by microcalorimetry. The power-time curves were plotted with a thermal activity monitor (TAM) air isothermal microcalorimeter and parameters such as growth rate constant (μ), peak-time (Tm), inhibitory ratio (I), and enhancement ratio (E) were calculated. The relationships between the concentration of Aconitum alkaloids and μ of E. coli or S. aureus were discussed. The results showed that Aconitum alkaloids had little effect on E. coli and had a potentially inhibitory effect on the growth of S. aureus.  相似文献   

7.
The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil (essential oil from Z. bungeanum Maxim.) on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The cytotoxicity of Z. bungeanum oil on dermal fibroblasts and epidermal keratinocytes was studied using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The rat skin was employed to determine the percutaneous penetration enhancement effect of Z. bungeanum oil on hydrophilic and lipophilic model drugs, i.e., 5-fluorouracil and indomethacin. The secondary structure changes of the rat stratum corneum (SC) were determined using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and saturated solubilities and SC/vehicle partition coefficients of two model drugs with and without Z. bungeanum oil were also measured to understand its related mechanisms of action. It was found that the half maximal inhibitory concentration (IC50) values of Z. bungeanum oil were significantly lower in HaCaT and CCC-ESF-1 cell lines compared to the well-established and standard penetration enhancer Azone. The Z. bungeanum oil at various concentrations effectively facilitated the percutaneous penetration of two model drugs across the rat skin. In addition, the mechanisms of permeation enhancement by Z. bungeanum oil could be explained with saturated solubility, SC/vehicle partition coefficient, and secondary structure changes of SC.  相似文献   

8.
Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%?84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%?66.00%).  相似文献   

9.
In this research, the conditions for extraction of phenolics from leaves of Ficus virens were optimized using response surface methodology (RSM). The extraction abilities of phenolics (EAP) and flavonoids (EAF), the 2,2-diphenyl-1-pierylhydrazyl (DPPH) free-radical scavenging potential, and the ferric reducing/antioxidant power (FRAP) were used as quality indicators. The results of single-factor experiments showed that temperature, ethanol concentration, extraction time, and the number of extraction cycles were the main influencing variables, and these provided key information for the central composite design. The results of RSM fitted well to a second degree polynomial model and more than 98% of the variability was explained. The ideal extraction conditions for EAP, EAF, DPPH free-radical scavenging potential, and FRAP were obtained. Considering the four quality indicators overall, the ideal extraction conditions were 58% ethanol at 57 °C for 37 min with three extraction cycles. At the ideal extraction conditions, the values of EAP, EAF, DPPH free-radical scavenging potential, and FRAP were 5.72%, 3.09%, 58.88 mg ascorbic acid equivalent (AAE)/g dry weight (DW), and 15.86 mg AAE/g DW, respectively. In addition, linear correlations were observed between EAP, EAF, and antioxidant potential.  相似文献   

10.
The antioxidant activities and total phenolic content of fermented Salvia miltiorrhiza with fungus Geomyces luteus were investigated. The results revealed that G. luteus fermentation could significantly improve the antioxidant activity and total phenolic content of S. miltiorrhiza. The main antioxidant constituents were characterized by spectroscopic analysis as salvianolic acids. High-performance liquid chromatography (HPLC) quantification also showed the enhanced content of salvianolic acid B after fermentation. The present study suggests that G. luteus fermentations are effective in the S. miltiorrhiza salvianolic acids’ enrichment process.  相似文献   

11.
以乙醚为改性剂,采用超临界CO2萃取法提取中药蛇床子的有效成分,并用GC／MS法对其化学成分和相对含量进行了分析．结果表明,与水蒸气蒸馏法比较,超临界CO2萃取法的产率较高,总萃取率为8．46％(w),蒸馏法提取蛇床子挥发油的产率较低,仅为1．01％(w);蛇床子超临界萃取物中香豆素类的相对含量约为67．63％,其蛇床子素相对含量占总香豆素的78．92％,而蒸馏法提取的挥发油中鉴定出一种香豆素成分,其相对含量仅为1．65％．因此,超临界CO2萃取法可以有效提取中药蛇床子的多种香豆素类成分,其方法为其他同类中药的开发和药学鉴定提供了参考依据．  相似文献   

12.
In the current study, caffeic acid was an important metabolite in the highly copper-tolerant plant Elsholtzia splendens. Preparation and purification of caffeic acid were performed on the dried biomass of the plants by means of sonication/ethanol extraction, followed by purification using a macroporous resin (D101 type) column and silica gel chromatography. The faint-yellow caffeic acid product was yielded with a purity of 98.46%, and it was chemically identified from spectra of Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR)/carbon nuclear magnetic resonance (13C NMR), and electrospray ionization mass spectrometry (ESI-MS). Caffeic acid is a possible product from the post-harvest processing of Elsholtzia splendens biomass.  相似文献   

13.
Objective: The intoxications caused by 2,4-dinitrophenol (2,4-DNP), even death, have been frequently reported in recent years. This study aims to investigate the dynamic changes of plasma toxin concentration and explore the clinical value of resin hemoperfusion (HP) in the treatment of patients with acute 2,4-DNP poisoning. Methods: We reported 16 cases of acute 2,4-DNP poisoning through occupational exposure due to ignoring the risk of poisoning. The blood samples were collected from the 14 survivors. According to the different treatments of resin HP, the survivors were divided into routine HP (n=5) and intensive HP (n=9) groups. Ultra high performance liquid chromatography/tandem mass spectroscopy (UPLC-MS/MS) was used to detect the 2,4-DNP concentration in plasma in this study. Results: The 14 survivors recovered very well after treatment. The initial plasma 2,4-DNP concentrations (C 1) of survivors ranged from 0.25 to 41.88 µg/ml (mean (12.56±13.93) µg/ml). A positive correlation existed between initial plasma 2,4-DNP concentration (C 1) and temperature. The elimination of 2,4-DNP was slow and persistent, and the total clearance rates of plasma toxin from the 1st to 3rd day (R 3), the 3rd to 7th day (R 3–7), and the 1st to 7th day (R 7), were only (53.03±14.04)%, (55.25±10.50)%, and (78.29±10.22)%, respectively. The plasma toxin was cleared up to 25 d after poisoning in most of the patients. The R 3, R 3–7, and R 7 in the intensive HP group were all apparently higher than those in the routine HP group, with statistical significance (P<0.05). Simultaneously, the elimination half-life (t 1/2) of 2,4-DNP in the intensive HP group was apparently shorter than that in the routine HP group, with statistical significance (P<0.05). Conclusions: The clinicians should be aware of this slow and persistent process in the elimination of plasma 2,4-DNP. Higher initial plasma toxin concentration resulted in a more severe fever for the patient. According to the limited data, longer and more frequent resin HP may accelerate to eliminate the poison.  相似文献   

14.
This study was conducted in an attempt to investigate the effectiveness of an educational card game we developed for learning human immunology. Two semesters of evaluation were included to examine the impact of the game on students’ understanding and perceptions of the game-based instruction. Ninety-nine senior high school students (11th graders) were recruited for the first evaluation, and the second-semester group consisted of 72 students (also 11th graders). The results obtained indicate that students did learn from the educational card game. Moreover, students who learned from playing the game significantly outperformed their counterparts in terms of their understanding of the processes and connections among different lines of immunological defense (first semester: t = 2.92, p < 0.01; second semester: t = 3.45, p < 0.01) according to the qualitative analysis of an open-ended question. They generally had positive perceptions toward the game-based instruction and its learning efficiency, and they felt the game-based instruction was much more interesting than traditional didactic lectures (first semester: t = 2.79, p < 0.01; second semester: t = 2.41, p < 0.05). This finding is evidence that the educational card game has potential to facilitate students’ learning of how the immune system works. The implications and suggestions for future work are further discussed.
Play is necessary for the development of higher intelligence; for if we were provided with perfected instincts, as insects are, life would be automatic and there would be no such thing as education and no increase of ability or intelligence, either in the individual or the species.— Mitchell and Mason, 1935 , 56–57
  相似文献   

15.
A total of 64 patients with β-lactam allergy and 30 control subjects were enrolled in a case-control study. This study is aimed to analyze the relationship between β-lactam allergy and 10 single nucleotide polymorphisms (SNPs) in interleukin-10 (IL-10), IL-13, IL-4Rα, high-affinity immunoglobulin E-receptor β chain (FcεRIβ), interferon γ receptor 2 (IFNGR2), and CYP3A4, and within the Han Chinese population of Northwest China. Genotyping for the SNPs was conducted using the Sequenom MassARRAY®platform. SPSS 17.0 was employed to analyze the statistical data and SHEsis was used to perform the haplotype reconstruction and analyze linkage disequilibrium of SNPs of IL-10 and IL-13. The results showed that the genotype distribution of CYP3A4 rs2242480/CT differed significantly between case and control groups of males (P=0.022; odds ratio (OR)=0.167, 95% confidence interval (CI): 0.032–0.867). Further analysis showed that CCA, CCG, and TAA haplotypes of IL-10 had no significant correlation in patients with β-lactam allergy. The correlation between CCT and CAC haplotypes of IL-13 and β-lactam allergy needs to be further studied. The analysis did not reveal any differences in the distribution of others gene polymorphisms between cases and controls.  相似文献   

16.
Gene and drug therapies are being developed to alleviate vision loss in patients with Stargardt’s disease and age-related macular degeneration (AMD). To evaluate the therapeutic effects of these treatments, organic solvents are routinely used to extract and quantify bisretinoid lipofuscin constituents, such as N-retinylidene-N-retinyl-ethanolamine (A2E) and all-trans-retinal dimer (ATR-dimer). By high-performance liquid chromatography (HPLC), we found that A2E and ATR-dimer were both altered by tetrahydrofuran (THF) and chloroform, but were stable in dimethyl sulfoxide (DMSO) or methanol (MeOH). In addition, cyclohexane and ethanol (EtOH) did not alter ATR-dimer, whereas an alteration of A2E occurred in EtOH. On the basis of these findings, we designed processes II–IV, generated by modifications of process I, a routine method to measure bisretinoid compounds in vivo. Extra amounts of either ATR-dimer or A2E in mouse eyecups were released by processes II–IV versus process I. Efforts to clarify the effects of organic solvents on lipofuscin pigments are important because such studies can guide the handling of these fluorophores in related experiments.  相似文献   

17.

Objective

This study examined the anti-adipogenic effects of extracts of Ficus deltoidea var. deltoidia and var. angustifolia, a natural slimming aid, on 3T3-L1 adipocytes.

Methods

Methanol and water extracts of leaves of the F. deltoidea varieties were analyzed to determine their total flavonoid content (TFC) and total phenolic content (TPC), respectively. The study was initiated by determining the maximum non-toxic dose (MNTD) of the methanol and water extracts for 3T3-L1 preadipocytes. Possible anti-adipogenic effects were then examined by treating 2-d post confluent 3T3-L1 preadipocytes with either methanol extract or water extract at MNTD and half MNTD (1/2MNTD), after which the preadipocytces were induced to form mature adipocytes. Visualisation and quantification of lipid content in mature adipocytes were carried out through oil red O staining and measurement of optical density (OD) at 520 nm, respectively.

Results

The TFCs of the methanol extracts were 1.36 and 1.97 g quercetin equivalents (QE)/100 g dry weight (DW), while the TPCs of the water extracts were 5.61 and 2.73 g gallic acid equivalents (GAE)/100 g DW for var. deltoidea and var. angustilofia, respectively. The MNTDs determined for methanol and water extracts were (300.0±28.3) and (225.0±21.2) μg/ml, respectively, for var. deltoidea, while much lower MNTDs [(60.0±2.0) μg/ml for methanol extracts and (8.0±1.0) μg/ml for water extracts] were recorded for var. angustifolia. Studies revealed that the methanol extracts of both varieties and the water extracts of var. angustifolia at either MNTD or 1/2MNTD significantly inhibited the maturation of preadipocytes. Conclusions: The inhibition of the formation of mature adipocytes indicated that leaf extracts of F. deltoidea could have potential anti-obesity effects.  相似文献   

18.
In 2013, Childbirth Connection published findings from a U.S. study of women’s pregnancy, childbirth, and postpartum experiences, Listening to Mothers III. In this issue of The Journal of Perinatal Education, we publish the major survey findings of both the pregnancy and birth survey and the postpartum survey. This editorial discusses some of the major findings of the childbirth survey. Listening to what mothers have to say about their experiences suggests a mandate to “listen up” to what mothers are telling us and continue to advocate for evidence-based maternity care. Articles in this issue of the journal are presented.  相似文献   

19.
Camellia seed oil (CSO) is rich in oleic acid and has a high number of active components, which give the oil high nutritional value and a variety of biological activity. The aim of the present study was to determine the changes in the content and distribution of total polar compounds (TPC) in CSO during heating. TPC were isolated by means of preparative flash chromatography and further analyzed by high-performance size-exclusion chromatography (HPSEC). The TPC content of CSO increased from 4.74% to 25.29%, showing a significantly lower formation rate as compared to that of extra virgin olive oil (EVOO) and soybean oil (SBO) during heating. Furthermore, heating also resulted in significant differences (P<0.05) in the distribution of TPC among these oils. Though the content of oxidized triacylglycerol dimers, oxidized triacylglycerol oligomers, and oxidized triacylglycerol monomers significantly increased in all these oils, their increased percentages were much less in CSO than those in EVOO, indicating that CSO has a greater ability to resist oxidation. This work may be useful for the food oil industry and consumers in helping to choose the correct oil and to decide on the useful lifetime of the oil.  相似文献   

20.
Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4 000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3 488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification.  相似文献   

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