ResearchPad - acetones https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Juvenile hormone suppresses aggregation behavior through influencing antennal gene expression in locusts]]> https://www.researchpad.co/article/elastic_article_7742 A behavioral change from shy solitarious individuals to highly social gregarious individuals is critical to the formation of disastrous swarms of locusts. However, the underlying molecular mechanism of behavioral plasticity regulated by hormones is still largely unknown. Here, we investigated the effect of juvenile hormone (JH) on the behavioral transition in fourth-instar gregarious and solitarious locusts. We found that JH induced the behavioral shift of the gregarious locust from attraction to repulsion to the volatiles of gregarious locusts. The solitarious locust significantly decreased repulsion behavior after deprivation of JH by precocene or knockdown of JHAMT, a key enzyme to synthesize JH. JH application on gregarious locusts caused significant expression alteration of genes, especially the olfactory genes TO and CSP in the antennae. We further demonstrated that the JH signaling pathway suppressed aggregation behavior in gregarious locusts by increasing TO1 expression and decreasing CSP3 expression at the same time. Our results suggested that internal physiological factors can directly modulate periphery olfactory system to produce behavioral plasticity.

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<![CDATA[Chemical composition, antioxidant, anti-inflammatory, and cytotoxic activities of Opuntia stricta cladodes]]> https://www.researchpad.co/article/5c59feb5d5eed0c48413531a

Background

The Opuntia spp. have been used in traditional medicine for many centuries. It is used in the management of diseases that involves oxidative stress, especially diabetes, obesity and cancer. Opuntia stricta (Haw) is one of the relatively unknown species in South Africa where it is regarded more as a weed. Because of this, not much is known about its chemical composition.

Aim

To determine the chemical composition, antioxidant, anti-inflammatory, and cytotoxic activities of Opuntia stricta cladodes.

Methods

The phytochemical composition of acetone, aqueous and ethanol extract of cladodes of Opuntia stricta (Haw), as well as the vitamins A, C and E of its dried weight cladodes and the antioxidant activities, were evaluated using standard in vitro methods. The anti-inflammatory and cytotoxic activities were evaluated using cell-based assays. The phytochemical composition and vitamins were determined spectrophotometrically, while the antioxidant activities were determined by DPPH, nitric oxide, hydrogen peroxide scavenging activity and phosphomolybdenum (total) antioxidant activity. Anti-inflammatory activity was determined using RAW 264.7 cells, while cytotoxicity was determined using U937 cells.

Results

The phytochemical composition showed a significant difference in the various extracts. The total phenolics were higher than other phytochemicals in all the extracts used. All the extracts displayed antioxidant activity, while most of the extracts showed anti-inflammatory activity. Only one extract showed cytotoxicity, and it was mild.

Conclusion

The results show that the Opuntia stricta is rich in polyphenolic compounds and has good antioxidant activity as well as anti-inflammatory activities.

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<![CDATA[Variation in the susceptibility of Anopheles gambiae to botanicals across a metropolitan region of Nigeria]]> https://www.researchpad.co/article/5c3fa595d5eed0c484ca6104

Pesticide resistance is normally associated with genetic changes, resulting in varied responses to insecticides between different populations. There is little evidence of resistance to plant allelochemicals; it is likely that their efficacy varies between genetically diverse populations, which may lead to the development of resistance in the future. This study evaluated the response of Anopheles gambiae (larvae and adults) from spatially different populations to acetone extracts of two botanicals, Piper guineense and Eugenia aromatica. Mosquito samples from 10 locations within Akure metropolis in Southwest Nigeria were tested for variation in susceptibility to the toxic effect of botanical extracts. The spatial distribution of the tolerance magnitude (T.M.) of the mosquito populations to the botanicals was also mapped. The populations of An. gambiae manifested significant differences in their level of tolerance to the botanicals. The centre of the metropolis was the hot spot of tolerance to the botanicals. There was a significant positive correlation between the adulticidal activities of both botanicals and initial knockdown. Hence, knockdown by these botanicals could be a predictor of their subsequent mortality. In revealing variation in response to botanical pesticides, our work has demonstrated that any future use of botanicals as alternative environmentally friendly vector control chemicals needs to be closely monitored to ensure that resistance does not develop.

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<![CDATA[Modified TCA/acetone precipitation of plant proteins for proteomic analysis]]> https://www.researchpad.co/article/5c21513bd5eed0c4843f93fc

Protein extracts obtained from cells or tissues often require removal of interfering substances for the preparation of high-quality protein samples in proteomic analysis. A number of protein extraction methods have been applied to various biological samples. TCA/acetone precipitation and phenol extraction, a common method of protein extraction, is thought to minimize protein degradation and activity of proteases as well as reduce contaminants like salts and polyphenols. However, the TCA/acetone precipitation method relies on the complete pulverization and repeated rinsing of tissue powder to remove the interfering substances, which is laborious and time-consuming. In addition, by prolonged incubation in TCA/acetone, the precipitated proteins are more difficult to re-dissolve. We have described a modified method of TCA/acetone precipitation of plant proteins for proteomic analysis. Proteins of cells or tissues were extracted using SDS-containing buffer, precipitated with equal volume of 20% TCA/acetone, and washed with acetone. Compared to classical TCA/acetone precipitation and simple acetone precipitation, this protocol generates comparable yields, spot numbers, and proteome profiling, but takes less time (ca. 45 min), thus avoiding excess protein modification and degradation after extended-period incubation in TCA/acetone or acetone. The modified TCA/acetone precipitation method is simple, fast, and suitable for proteomic analysis of various plant tissues in proteomic analysis.

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<![CDATA[A Statistical Evaluation of Methods of In-Vitro Growth Assessment for Phyllosticta citricarpa: Average Colony Diameter vs. Area]]> https://www.researchpad.co/article/5989db4fab0ee8fa60bdb890

Fungal growth inhibition on solid media has been historically measured and calculated based on the average of perpendicular diameter measurements of growth on fungicide amended media. We investigated the sensitivity of the calculated area (DA) and the measured area (MA) for assessing fungicide growth inhibition of the ascomycete, Phyllosticta citricarpa on solid media. Both the calculated, DA and the actual measured area, MA were adequate for distinguishing significant treatment effects of fungicide on fungal growth, however MA was more sensitive at identifying significant differences between the controls and fungicide concentrations below 5 ppm.

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<![CDATA[Impact of Exhaled Breath Acetone in the Prognosis of Patients with Heart Failure with Reduced Ejection Fraction (HFrEF). One Year of Clinical Follow-up]]> https://www.researchpad.co/article/5989da71ab0ee8fa60b94fc1

Background

The identification of new biomarkers of heart failure (HF) could help in its treatment. Previously, our group studied 89 patients with HF and showed that exhaled breath acetone (EBA) is a new noninvasive biomarker of HF diagnosis. However, there is no data about the relevance of EBA as a biomarker of prognosis.

Objectives

To evaluate whether EBA could give prognostic information in patients with heart failure with reduced ejection fraction (HFrEF).

Methods

After breath collection and analysis by gas chromatography-mass spectrometry and by spectrophotometry, the 89 patients referred before were followed by one year. Study physicians, blind to the results of cardiac biomarker testing, ascertained vital status of each study participant at 12 months.

Results

The composite endpoint death and heart transplantation (HT) were observed in 35 patients (39.3%): 29 patients (32.6%) died and 6 (6.7%) were submitted to HT within 12 months after study enrollment. High levels of EBA (≥3.7μg/L, 50th percentile) were associated with a progressively worse prognosis in 12-month follow-up (log-rank = 11.06, p = 0.001). Concentrations of EBA above 3.7μg/L increased the risk of death or HT in 3.26 times (HR = 3.26, 95%CI = 1.56–6.80, p = 0.002) within 12 months. In a multivariable cox regression model, the independent predictors of all-cause mortality were systolic blood pressure, respiratory rate and EBA levels.

Conclusions

High EBA levels could be associated to poor prognosis in HFrEF patients.

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<![CDATA[Phytochemical investigation of Aloe pulcherrima roots and evaluation for its antibacterial and antiplasmodial activities]]> https://www.researchpad.co/article/5989db50ab0ee8fa60bdc1e4

Medicinal plants with documented traditional uses remain an important source for the treatment of a wide range of ailments. Evidence shows that majority of the Ethiopian population are still dependent on traditional medicine. Aloe pulcherrima Gilbert & Sebsebe is one of the endemic Aloe species traditionally used for the treatment of malaria and wound healing in central, Southern and Northern part of Ethiopia. The aim of the current study was, therefore, to isolate active compounds from roots of A. pulcherrima and evaluate for their antibacterial and antiplasmodial activities using standard test strains. Bioassay-guided sequential extraction and column chrom-atographic separation were employed for the isolation of bioactive pure compounds. The structures of the compounds were determined by 1D and 2D NMR spectro-scopic techniques. Disk diffusion method was employed to evaluate the antibacterial activities of the isolated compounds against four bacterial strains specifically (Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853). The malaria SYBR Green I-based in vitro assay technique was used for in vitro antiplasmodial activity evaluation of the compounds against chloroquine resistant (D6) and -sensitive (W2) strains of P. falciparum. Three compounds, chrysophanol, aloesaponarin I and aloesaponarin II were isolated from the acetone extracts of roots of A. pulcherrima. Evaluation of antibacterial activities revealed that aloesaponarin I and aloesaponarin II had significant activities against all the bacterial strains with inhibition zone diameters ranging from 18–27 mm as compared to the reference drug (gentamicin), which displayed inhibition zone diameter ranging between 20 mm (B. subtilis) and 25 mm (P. aeruginosa). The isolated compounds showed moderate in vitro antiplasmodial activity against both chloroquine resistant (W2) -sensitive (D6) strains. Isolation of chrysophanol, aloesaponarin I and aloesaponarin II from roots of A. pulcherrima is the first report of its kind. The finding could be used for further comprehensive evaluation of the isolated compounds for their antibacterial and antimalarial activities besides consideration of the same for potent drug development.

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<![CDATA[Novel biphenyl ester derivatives as tyrosinase inhibitors: Synthesis, crystallographic, spectral analysis and molecular docking studies]]> https://www.researchpad.co/article/5989db4fab0ee8fa60bdbc5a

Biphenyl-based compounds are clinically important for the treatments of hypertension and inflammatory, while many more are under development for pharmaceutical uses. In the present study, a series of 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl benzoates, 2(a-q), and 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl pyridinecarboxylate, 2(r-s) were synthesized by reacting 1-([1,1'-biphenyl]-4-yl)-2-bromoethan-1-one with various carboxylic acids using potassium carbonate in dimethylformamide at ambient temperature. Single-crystal X-ray diffraction studies revealed a more closely packed crystal structure can be produced by introduction of biphenyl moiety. Five of the compounds among the reported series exhibited significant anti-tyrosinase activities, in which 2p, 2r and 2s displayed good inhibitions which are comparable to standard inhibitor kojic acid at concentrations of 100 and 250 μg/mL. The inhibitory effects of these active compounds were further confirmed by computational molecular docking studies and the results revealed the primary binding site is active-site entrance instead of inner copper binding site which acted as the secondary binding site.

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<![CDATA[Exercise Activates p53 and Negatively Regulates IGF-1 Pathway in Epidermis within a Skin Cancer Model]]> https://www.researchpad.co/article/5989da77ab0ee8fa60b973e2

Exercise has been previously reported to lower cancer risk through reducing circulating IGF-1 and IGF-1-dependent signaling in a mouse skin cancer model. This study aims to investigate the underlying mechanisms by which exercise may down-regulate the IGF-1 pathway via p53 and p53-related regulators in the skin epidermis. Female SENCAR mice were pair-fed an AIN-93 diet with or without 10-week treadmill exercise at 20 m/min, 60 min/day and 5 days/week. Animals were topically treated with TPA 2 hours before sacrifice and the target proteins in the epidermis were analyzed by both immunohistochemistry and Western blot. Under TPA or vehicle treatment, MDM2 expression was significantly reduced in exercised mice when compared with sedentary control. Meanwhile, p53 was significantly elevated. In addition, p53-transcriptioned proteins, i.e., p21, IGFBP-3, and PTEN, increased in response to exercise. There was a synergy effect between exercise and TPA on the decreased MDM2 and increased p53, but not p53-transcripted proteins. Taken together, exercise appeared to activate p53, resulting in enhanced expression of p21, IGFBP-3, and PTEN that might induce a negative regulation of IGF-1 pathway and thus contribute to the observed cancer prevention by exercise in this skin cancer model.

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<![CDATA[A Device-Independent Evaluation of Carbonyl Emissions from Heated Electronic Cigarette Solvents]]> https://www.researchpad.co/article/5989db31ab0ee8fa60bd2093

Objectives

To investigate how the two main electronic (e-) cigarette solvents—propylene glycol (PG) and glycerol (GL)—modulate the formation of toxic volatile carbonyl compounds under precisely controlled temperatures in the absence of nicotine and flavor additives.

Methods

PG, GL, PG:GL = 1:1 (wt/wt) mixture, and two commercial e-cigarette liquids were vaporized in a stainless steel, tubular reactor in flowing air ranging up to 318°C to simulate e-cigarette vaping. Aerosols were collected and analyzed to quantify the amount of volatile carbonyls produced with each of the five e-liquids.

Results

Significant amounts of formaldehyde and acetaldehyde were detected at reactor temperatures ≥215°C for both PG and GL. Acrolein was observed only in e-liquids containing GL when reactor temperatures exceeded 270°C. At 318°C, 2.03±0.80 μg of formaldehyde, 2.35±0.87 μg of acetaldehyde, and a trace amount of acetone were generated per milligram of PG; at the same temperature, 21.1±3.80 μg of formaldehyde, 2.40±0.99 μg of acetaldehyde, and 0.80±0.50 μg of acrolein were detected per milligram of GL.

Conclusions

We developed a device-independent test method to investigate carbonyl emissions from different e-cigarette liquids under precisely controlled temperatures. PG and GL were identified to be the main sources of toxic carbonyl compounds from e-cigarette use. GL produced much more formaldehyde than PG. Besides formaldehyde and acetaldehyde, measurable amounts of acrolein were also detected at ≥270°C but only when GL was present in the e-liquid. At 215°C, the estimated daily exposure to formaldehyde from e-cigarettes, exceeded United States Environmental Protection Agency (USEPA) and California Office of Environmental Health Hazard Assessment (OEHHA) acceptable limits, which emphasized the need to further examine the potential cancer and non-cancer health risks associated with e-cigarette use.

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<![CDATA[Toxic and hormetic-like effects of three components of citrus essential oils on adult Mediterranean fruit flies (Ceratitis capitata)]]> https://www.researchpad.co/article/5989db5bab0ee8fa60bdfdaf

Plant essential oils (EOs) and a wide range of their individual components are involved in a variety of biological interactions with insect pests including stimulatory, deterrent, toxic and even hormetic effects. Both the beneficial and toxic properties of citrus EOs on the Mediterranean fruit fly (medfly) have been experimentally evidenced over the last years. However, no information is available regarding the toxic or beneficial effects of the major components of citrus EOs via contact with the adults of the Mediterranean fruit fly. In the present study, we explored the toxicity of limonene, linalool and α-pinene (3 of the main compounds of citrus EOs) against adult medflies and identified the effects of sub-lethal doses of limonene on fitness traits in a relaxed [full diet (yeast and sugar)] and in a stressful (sugar only) feeding environment. Our results demonstrate that all three compounds inferred high toxicity to adult medflies regardless of the diet, with males being more sensitive than females. Sub-lethal doses of limonene (LD20) enhanced the lifespan of adult medflies when they were deprived of protein. Fecundity was positively affected when females were exposed to limonene sub-lethal doses. Therefore, limonene, a major constituent of citrus EOs, induces high mortality at increased doses and positive effects on life history traits of medfly adults through contact at low sub-lethal doses. A hormetic-like effect of limonene to adult medflies and its possible underlying mechanisms are discussed.

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<![CDATA[Juvenile Hormone Is Required in Adult Males for Drosophila Courtship]]> https://www.researchpad.co/article/5989da48ab0ee8fa60b8c2be

Juvenile Hormone (JH) has a prominent role in the regulation of insect development. Much less is known about its roles in adults, although functions in reproductive maturation have been described. In adult females, JH has been shown to regulate egg maturation and mating. To examine a role for JH in male reproductive behavior we created males with reduced levels of Juvenile Hormone Acid O-Methyl Transferase (JHAMT) and tested them for courtship. JHAMT regulates the last step of JH biosynthesis in the Corpora Allata (CA), the organ of JH synthesis. Males with reduced levels of JHAMT showed a reduction in courtship that could be rescued by application of Methoprene, a JH analog, shortly before the courtship assays were performed. In agreement with this, reducing JHAMT conditionally in mature flies led to courtship defects that were rescuable by Methoprene. The same result was also observed when the CA were conditionally ablated by the expression of a cellular toxin. Our findings demonstrate that JH plays an important physiological role in the regulation of male mating behavior.

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<![CDATA[Exhaled volatile substances mirror clinical conditions in pediatric chronic kidney disease]]> https://www.researchpad.co/article/5989db5cab0ee8fa60be0256

Monitoring metabolic adaptation to chronic kidney disease (CKD) early in the time course of the disease is challenging. As a non-invasive technique, analysis of exhaled breath profiles is especially attractive in children. Up to now, no reports on breath profiles in this patient cohort are available. 116 pediatric subjects suffering from mild-to-moderate CKD (n = 48) or having a functional renal transplant KTx (n = 8) and healthy controls (n = 60) matched for age and sex were investigated. Non-invasive quantitative analysis of exhaled breath profiles by means of a highly sensitive online mass spectrometric technique (PTR-ToF) was used. CKD stage, the underlying renal disease (HUS; glomerular diseases; abnormalities of kidney and urinary tract or polycystic kidney disease) and the presence of a functional renal transplant were considered as classifiers. Exhaled volatile organic compound (VOC) patterns differed between CKD/ KTx patients and healthy children. Amounts of ammonia, ethanol, isoprene, pentanal and heptanal were higher in patients compared to healthy controls (556, 146, 70.5, 9.3, and 5.4 ppbV vs. 284, 82.4, 49.6, 5.30, and 2.78 ppbV). Methylamine concentrations were lower in the patient group (6.5 vs 10.1 ppbV). These concentration differences were most pronounced in HUS and kidney transplanted patients. When patients were grouped with respect to degree of renal failure these differences could still be detected. Ammonia accumulated already in CKD stage 1, whereas alterations of isoprene (linked to cholesterol metabolism), pentanal and heptanal (linked to oxidative stress) concentrations were detectable in the breath of patients with CKD stage 2 to 4. Only weak associations between serum creatinine and exhaled VOCs were noted. Non-invasive breath testing may help to understand basic mechanisms and metabolic adaptation accompanying progression of CKD. Our results support the current notion that metabolic adaptation occurs early during the time course of CKD.

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<![CDATA[Kinetic Study of Acetone-Butanol-Ethanol Fermentation in Continuous Culture]]> https://www.researchpad.co/article/5989db09ab0ee8fa60bc992b

Acetone-butanol-ethanol (ABE) fermentation by clostridia has shown promise for industrial-scale production of biobutanol. However, the continuous ABE fermentation suffers from low product yield, titer, and productivity. Systems analysis of the continuous ABE fermentation will offer insights into its metabolic pathway as well as into optimal fermentation design and operation. For the ABE fermentation in continuous Clostridium acetobutylicum culture, this paper presents a kinetic model that includes the effects of key metabolic intermediates and enzymes as well as culture pH, product inhibition, and glucose inhibition. The kinetic model is used for elucidating the behavior of the ABE fermentation under the conditions that are most relevant to continuous cultures. To this end, dynamic sensitivity analysis is performed to systematically investigate the effects of culture conditions, reaction kinetics, and enzymes on the dynamics of the ABE production pathway. The analysis provides guidance for future metabolic engineering and fermentation optimization studies.

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<![CDATA[Carbonyl-based blue autofluorescence of proteins and amino acids]]> https://www.researchpad.co/article/5989db5cab0ee8fa60be0058

Intrinsic protein fluorescence is inextricably linked to the near-UV autofluorescence of aromatic amino acids. Here we show that a novel deep-blue autofluorescence (dbAF), previously thought to emerge as a result of protein aggregation, is present at the level of monomeric proteins and even poly- and single amino acids. Just as its aggregation-related counterpart, this autofluorescence does not depend on aromatic residues, can be excited at the long wavelength edge of the UV and emits in the deep blue. Differences in dbAF excitation and emission peaks and intensities from proteins and single amino acids upon changes in solution conditions suggest dbAF’s sensitivity to both the chemical identity and solution environment of amino acids. Autofluorescence comparable to dbAF is emitted by carbonyl-containing organic solvents, but not those lacking the carbonyl group. This implicates the carbonyl double bonds as the likely source for the autofluorescence in all these compounds. Using beta-lactoglobulin and proline, we have measured the molar extinction coefficients and quantum yields for dbAF in the monomeric state. To establish its potential utility in monitoring protein biophysics, we show that dbAF emission undergoes a red-shift comparable in magnitude to tryptophan upon thermal denaturation of lysozyme, and that it is sensitive to quenching by acrylamide. Carbonyl dbAF therefore provides a previously neglected intrinsic optical probe for investigating the structure and dynamics of amino acids, proteins and, by extension, DNA and RNA.

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<![CDATA[Comparison of Adsorption/Desorption of Volatile Organic Compounds (VOCs) on Electrospun Nanofibers with Tenax TA for Potential Application in Sampling]]> https://www.researchpad.co/article/5989db2fab0ee8fa60bd1e92

The objective of this study was to compare the adsorption/desorption of target compounds on homemade electrospun nanofibers, polystyrene (PS) nanofibers, acrylic resin (AR) nanofibers and PS-AR composite nanofibers with Tenax TA. Ten volatile organic compounds (VOCs) were analyzed by preconcentration onto different sorbents followed by desorption (thermal and solvent orderly) and analysis by capillary gas chromatography. In comparison to Tenax TA, the electrospun nanofibers displayed a significant advantage in desorption efficiency and adsorption selectivity. Stability studies were conducted as a comparative experiment between PS-AR nanofibers and Tenax TA using toluene as the model compound. No stability problems were observed upon storage of toluene on both PS-AR nanofibers and Tenax TA over 60 hours period when maintained in an ultra-freezer (−80°C). The nanofibers provided slightly better stability for the adsorbed analytes than Tenax TA under other storage conditions. In addition, the nanofibers also provided slightly better precision than Tenax TA. The quantitative adsorption of PS-AR nanofibers exhibited a good linearity, as evidenced by the 0.988–0.999 range of regression coefficients (R). These results suggest that for VOCs sampling the electrospun nanofibers can be a potential ideal adsorbent.

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<![CDATA[Changes in the Bacterial Community Structure of Remediated Anthracene-Contaminated Soils]]> https://www.researchpad.co/article/5989daf3ab0ee8fa60bc1eac

Mixing soil or adding earthworms (Eisenia fetida (Savigny, 1826)) accelerated the removal of anthracene, a polycyclic aromatic hydrocarbon, from a pasture and an arable soil, while a non-ionic surfactant (Surfynol® 485) inhibited the removal of the contaminant compared to the untreated soil. It was unclear if the treatments affected the soil bacterial community and consequently the removal of anthracene. Therefore, the bacterial community structure was monitored by means of 454 pyrosequencing of the 16S rRNA gene in the pasture and arable soil mixed weekly, amended with Surfynol® 485, E. fetida or organic material that served as food for the earthworms for 56 days. In both soils, the removal of anthracene was in the order: mixing soil weekly (100%) > earthworms applied (92%) > organic material applied (77%) > untreated soil (57%) > surfactant applied (34%) after 56 days. There was no clear link between removal of anthracene from soil and changes in the bacterial community structure. On the one hand, application of earthworms removed most of the contaminant from the arable soil and had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of the Acidobacteria, Chloroflexi and Gemmatimonadetes, and an increase in that of the Proteobacteria compared to the unamended soil. Mixing the soil weekly removed all anthracene from the arable soil, but had little or no effect on the bacterial community structure. On the other hand, application of the surfactant inhibited the removal of anthracene from the arable soil compared to the untreated soil, but had a strong effect on the bacterial community structure, i.e. a decrease in the relative abundance of Cytophagia (Bacteroidetes), Chloroflexi, Gemmatimonadetes and Planctomycetes and an increase in that of the Flavobacteria (Bacteroidetes) and Proteobacteria. Additionally, the removal of anthracene was similar in the different treatments of both the arable and pasture soil, but the effect of application of carrot residue, earthworms or the surfactant on the bacterial community structure was more accentuated in the arable soil than in the pasture soil. It was found that removal of anthracene was not linked to changes in the bacterial community structure.

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<![CDATA[Interaction between Antibacterial Peptide Apep10 and Escherichia coli Membrane Lipids Evaluated Using Liposome as Pseudo-Stationary Phase]]> https://www.researchpad.co/article/5989daceab0ee8fa60bb5296

Liposomes constructed from Escherichia coli membrane lipids were used as a pseudo-stationary phase in capillary electrophoresis and immobilised liposome chromatography to evaluate the interaction between antibacterial peptide (ABP) Apep10 and bacterial membrane lipids. The peptide mobility decreased as the concentration of liposomes increased, providing evidence for the existence of this interaction. The binding constant between Apep10 and the Escherichia coli membranes lipid liposome was higher than that of Apep10 with a mixed phospholipids liposome at the same temperature. The capillary electrophoresis results indicate that the binding ability of Apep10 with a liposome was dependent on the liposome’s lipid compositions. Thermodynamic analysis by immobilised liposome chromatography indicated that hydrophobic and electrostatic effects contributed to the partitioning of Apep10 in the membrane lipids. The liposomes constructed from bacterial membrane lipid were more suitable as the model membranes used to study dynamic ABP/membrane interactions than those constructed from specific ratios of particular phospholipids, with its more biomimetic phospholipid composition and contents. This study provides an appropriate model for the evaluation of ABP-membrane interactions.

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<![CDATA[Noninvasive Recognition and Biomarkers of Early Allergic Asthma in Cats Using Multivariate Statistical Analysis of NMR Spectra of Exhaled Breath Condensate]]> https://www.researchpad.co/article/5989daf9ab0ee8fa60bc4252

Asthma is prevalent in children and cats, and needs means of noninvasive diagnosis. We sought to distinguish noninvasively the differences in 53 cats before and soon after induction of allergic asthma, using NMR spectra of exhaled breath condensate (EBC). Statistical pattern recognition was improved considerably by preprocessing the spectra with probabilistic quotient normalization and glog transformation. Classification of the 106 preprocessed spectra by principal component analysis and partial least squares with discriminant analysis (PLS-DA) appears to be impaired by variances unrelated to eosinophilic asthma. By filtering out confounding variances, orthogonal signal correction (OSC) PLS-DA greatly improved the separation of the healthy and early asthmatic states, attaining 94% specificity and 94% sensitivity in predictions. OSC enhancement of multi-level PLS-DA boosted the specificity of the prediction to 100%. OSC-PLS-DA of the normalized spectra suggest the most promising biomarkers of allergic asthma in cats to include increased acetone, metabolite(s) with overlapped NMR peaks near 5.8 ppm, and a hydroxyphenyl-containing metabolite, as well as decreased phthalate. Acetone is elevated in the EBC of 74% of the cats with early asthma. The noninvasive detection of early experimental asthma, biomarkers in EBC, and metabolic perturbation invite further investigation of the diagnostic potential in humans.

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<![CDATA[The Activation Effects of Low Level Isopropyl Alcohol Exposure on Arterial Blood Pressures Are Associated with Decreased 5-Hydroxyindole Acetic Acid in Urine]]> https://www.researchpad.co/article/5989daeaab0ee8fa60bbef5d

Purposes

The objectives of this paper are to study the impact of low level isopropyl alcohol exposure on blood pressure and to explore its potential mechanism.

Methods

This cross-sectional study was based on a prospective occupational cohort in south China, which focusing on occupational risk factors related cardiovascular health problems. A total of 283 participants (200 low isopropyl alcohol exposed workers and 83 controls) was finally enrolled in this study. Linear regression models were used to analyze the relationship between arterial blood pressures and low level isopropyl alcohol exposure. We used mediation method to explore possible mediated roles of neurogenic factors.

Results

Systolic blood pressure (SBP, 123±10 vs. 118±11), diastolic blood pressure (DBP, 79±7 vs. 74±7) and mean blood pressure (MBP, 93±8 vs. 89±9) were different between the exposed group and the control group (p < 0.01). After adjusting for covariates, the difference was still significant. Besides, isopropyl alcohol and smoking had an interactive effect on DBP and MBP (p < 0.05). Furthermore, we observed a mediated effect of 5-hydroxyindole acetic acid (5-HIAA) on isopropyl alcohol exposure induced arterial blood pressure increase, which accounted for about 25%.

Conclusions

Our results suggest that low level isopropyl alcohol exposure is a potential risk factor for the increased arterial blood pressure and 5-HIAA partly mediates the association between low level isopropyl alcohol exposure and arterial blood pressures.

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