Low levels of Cd2+ combined with procymidone may cause ovarian damage in mice via unfolded protein response

As no study about the combined effect of low levels of Cd2+ with procymidone (PCM) on organs and organisms, we investigated their actions on mouse-ovary in vivo and in vitro. Four-week mice were treated with corn oil for the control group, corn oil + 0.0045 mg/L Cd2+ (CdCl2 was dissolved in ultrapure water and freely consumed by mice) for Cd2+ group, 50 mg/kg/d PCM (suspended in corn oil and administered orally to mice) for PCM group, and 50 mg/kg/d PCM + 0.0015 (0.0045 and 0.0135) mg/L Cd2+ for L+ (M+ and H+) PCM group for 21 days. For in vitro experiment, the cultured ovaries were treated with acetone for the control group, 0.1% acetone + 8.4 μg/L Cd2+ for the Cd2+ group, 0.63 mg/L PCM (dissolved in acetone) for the PCM-group, and 0.63 mg/L PCM + 2.8 (8.4 and 25.2) μg/L Cd2+ for L+ (M+ and H+) PCM group for 7 days. Mouse body weight in each treatment group, the weight and volume of ovaries in all PCM groups were lower than the control. Both in vivo and in vitro, all-stage follicle numbers were lower in M+PCM and H+PCM groups, whereas the atretic follicles and CASPASE3/8 were higher; meanwhile, lower estradiol and progesterone and higher unfolded protein response (UPR) members in all PCM groups. L+, M+, and H+PCM groups had further ovarian damage and stronger UPR than PCM groups, as did M+PCM groups over Cd2+ groups. It is hypothesized low-level PCM and Cd2+ may mutually promote each other's triggered UPR and exacerbate ovarian damage.

Transcriptome analysis reveals limited toxic effects of the UV-filter benzophenone-3 (BP-3) on the hermatypic coral Acropora tenuis and its symbiotic dinoflagellates

This study aimed to investigate the toxic and transcriptomic effects of the ultraviolet filter benzophenone-3 (BP-3) on Acropora tenuis and its symbiotic dinoflagellates while using acetone as a solvent. Seven-day exposure to 50 and 500 μg/L, which is higher than most BP-3 records from coastal waters, did not affect coral colour or dinoflagellate photosynthesis. Differentially expressed genes (DEGs) between seawater and solvent controls were <20 in both corals and dinoflagellates. Eleven coral DEGs were detected after treatment with 50 μg/L BP-3. Fourteen coral DEGs, including several fluorescent protein genes, were detected after treatment with 500 μg/L BP-3. In contrast, no dinoflagellate DEGs were detected in the BP-3 treatment group. These results suggest that the effects of 50-500 μg/L BP-3 on adult A. tenuis and its dinoflagellates are limited. Our experimental methods with lower acetone toxicity provide a basis for establishing standard ecotoxicity tests for corals.

Formylpeptide receptor 1 contributes to epidermal barrier dysfunction-induced skin inflammation through NOD-like receptor C4-dependent keratinocyte activation

BACKGROUND

Skin barrier dysfunction may both initiate and aggravate skin inflammation. However, the mechanisms involved in the inflammation process remain largely unknown.

OBJECTIVES

We sought to determine how skin barrier dysfunction enhances skin inflammation and molecular mechanisms.

METHODS

Skin barrier defect mice were established by tape stripping or topical use of acetone on wildtype mice, or filaggrin deficiency. RNA-Seq was employed to analyse the differentially expressed genes in mice with skin barrier defects. Primary human keratinocytes were transfected with formylpeptide receptor (FPR)1 or protein kinase R-like endoplasmic reticulum (ER) kinase (PERK) small interfering RNA to examine the effects of these gene targets. The expressions of inflammasome NOD-like receptor (NLR)C4, epidermal barrier genes and inflammatory mediators were evaluated.

RESULTS

Mechanical (tape stripping), chemical (acetone) or genetic (filaggrin deficiency) barrier disruption in mice amplified the expression of proinflammatory genes, with transcriptomic profiling revealing overexpression of formylpeptide receptor (Fpr1) in the epidermis. Treatment with the FPR1 agonist fMLP in keratinocytes upregulated the expression of the NLRC4 inflammasome and increased interleukin-1β secretion through modulation of ER stress via the PERK-eIF2α-C/EBP homologous protein pathway. The activation of the FPR1-NLRC4 axis was also observed in skin specimens from old healthy individuals with skin barrier defect or elderly mice. Conversely, topical administration with a FPR1 antagonist, or Nlrc4 silencing, led to the normalization of barrier dysfunction and alleviation of inflammatory skin responses in vivo.

CONCLUSIONS

In summary, our findings show that the FPR1-NLRC4 inflammasome axis is activated upon skin barrier disruption and may explain exaggerated inflammatory responses that are observed in disease states characterized by epidermal dysfunction. Pharmacological inhibition of FPR1 or NLRC4 represents a potential therapeutic target.

Artemisia vulgaris L., Artemisia alba Turra and their constituents reduce mitomycin C-induced genomic instability in human peripheral blood lymphocytes in vitro

This study aimed to evaluate the effect of aqueous and acetone extracts from Artemisia vulgaris L. (AV) and Artemisia alba Turra (AA), and two major polyphenols compounds (3,5-dihydroxybenzoic acid and quercetin-3-O-glucopyranoside) presented in both extracts of the plants against mitomycin C (MMC)-induced genomic instability. Genomic instability was measured using cytokinesis block micronucleus (MN) assay in human peripheral blood lymphocytes (PBLs) in vitro by analyzing two biomarkers - MN and nuclear division index (NDI). Extracts were tested in a concentration-dependent manner (10-250 µg/mL), while 3,5-dihydroxybenzoic acid and quercetin-3-O-glucopyranoside were tested in three different concentrations, in combination with 0.5 µg/mL of MMC. Aqueous and acetone extracts obtained from both plants significantly reduced MMC-induced MN frequency in PBLs, compared to positive control cells (p < 0.05). Extracts from AV did not affect NDI, whereas the concentrations of 10-100 μg/mL of aqueous and acetone AA extracts significantly elevated MMC-decreased NDI values in comparison to positive control cells (p < 0.05). Combined treatment of 3,5-dihydroxybenzoic acid and MMC showed a significant reduction of MMC-induced MN frequency, while quercetin-3-O-glucopyranoside increased MN frequency compared to positive control cells (p < 0.05). Both compounds decreased NDI values but only at the highest tested concentration of quercetin-3-O-glucopyranoside it was of greater significance. In conclusion, all extracts from AV and AA and 3,5-dihydroxybenzoic acid showed protective effect, whereby aqueous AA demonstrated the highest protective effect on MMC- induced genomic instability, while quercetin-3-O-glucopyranoside showed co-mutagen effect.

Effect of various concentrations of common organic solvents on the growth and proliferation ability of Candida glabrata and their permissible limits for addition in drug susceptibility testing

Objectives

Dimethyl sulfoxide (DMSO), acetone, ethanol, and methanol are organic solvents commonly used for dissolving drugs in antimicrobial susceptibility testing. However, these solvents have certain antimicrobial activity. Currently, standardized criteria for the selection and dosage of drug solvents in drug susceptibility testing research are lacking. The study aims to provide experimental evidence for the selection and addition limit of drug solvents for the in vitro antifungal susceptibility test of Candida glabrata (C. glabrata).

Methods

According to the recommendation of the Clinical and Laboratory Standards Institute (CLSI) M27-A3, a 0.5 McFarland C. glabrata suspension was prepared and then diluted 1:1,000. Next, a gradient dilution method was used to prepare 20%, 10%, 5%, and 2.5% DMSO/acetone/ethanol/methanol. The mixture was plated onto a 96-well plate and incubated at a constant temperature of 35 °C for 48 h. The inhibitory effects of DMSO, acetone, ethanol, and methanol on C. glabrata growth and proliferation were analyzed by measuring optical density values at 600 nm (OD600 values).

Results

After 48 h incubation, the OD600 values of C. glabrata decreased to different extents in the presence of the four common organic solvents. The decrease in the OD600 values was greater with increasing concentrations within the experimental concentration range. When DMSO and acetone concentrations were higher than 2.5% (containing 2.5%) and methanol and ethanol concentrations were higher than 5.0% (containing 5.0%), the differences were statistically significant compared with the growth control wells without any organic solvent (P < 0.05).

Conclusion

All four organic solvents could inhibit C. glabrata growth and proliferation. When used as solvents for drug sensitivity testing in C. glabrata, the concentrations of DMSO, acetone, ethanol, and methanol should be below 2.5%, 2.5%, 5%, and 5%, respectively.

Methanol and acetone extracts from the leaves of selected aromatic plants affect survival of field collected Anopheles arabiensis (Diptera: Culicidae) from Kisumu, Kenya

The massive and inappropriate use of synthetic insecticides is causing significant and increasing environmental disruption. Therefore, developing effective natural mosquitocidal compounds could be an alternative tool for malarial vector control. The present study investigates the larvicidal and adulticidal effect of methanol and acetone extracts of leaves from Lippia chevalieri, Lippia multiflora, Cymbopogon schoenanthus, and Lantana camara against Anopheles arabiensis, to control the most widespread vector transmitting malaria in sub-Saharan. Africa. Extracts were evaluated following WHO modified test procedure against third- to fourth-instar larvae and, non-blood-fed females from 3- to 5-day-old field populations of An. arabiensis under laboratory conditions using WHO larval and CDC bottle bioassays, respectively. Mortality was recorded after 24-h exposure and several compounds were identified in the extracts. The methanolic and acetonic extracts of L. camara were effective against larvae showing lethal concentrations to 50% (LC50) of the population, at 89.48 and 58.72 ppm, respectively. The acetonic extracts of C. schoenanthus and L. chevalieri showed higher toxicities LC50s of 0.16% and 0.22% against female adults, respectively. The methanolic extracts of L. multiflora and L. chevalieri LC50s were effective at 0.17% and 0.27%, respectively, against female adults. These results indicate that the plant extracts tested may represent effective means to control An. arabiensis when used to treat the surface of the marshes.

Exogenous acetone O-(2-naphthylsulfonyl)oxime improves the adverse effects of excess copper by copper detoxification systems in maize

The current study is to elucidate the responses of maize seedlings to excess copper and acetone O-(2-naphthylsulfonyl)oxime (NS) pretreatment. The study was divided into the following experimental groups: 18 h distilled water (DW) control (C), 6 h 0.3 mM NS + then 12 h DW (NS), 6 h DW + then 12 h 1 mM CuSO4.5H2O (CuS), 0.3 mM NS for 6 h + then 1 mM CuSO4.5H2O (NS + CuS) for 12 h. When the NS + CuS group is compared with the CuS group; It accumulated 10% more copper, while the ABA, H2O2, MDA, and carotenoid contents decreased significantly, the total chlorophyll, proline, gallic acid, ascorbic acid, catechol, trans-P-qumaric acid, and cinnamic acid contents increased. While SOD activity, which is one of the antioxidant system enzymes, decreased with NS application, GPX, CAT, and APX activities increased despite copper stress. When all the findings are evaluated as a whole, exogenous NS, despite excessive copper, ameliorated the adverse effects of copper stress by increasing the effectiveness of the enzymatic and non-enzymatic components of the antioxidant system and the contents of phenolic substances. In addition, increasing the copper content by 10% reveals its importance in terms of NS phytoremediation.Abbreviation: Style-sheet: When full form and abbreviated form both are used as keywords, retain both as provided by the author.

Vermitoxicity of aged biochar and exploring potential damage factors

Although biochar is a promising soil amendment, its characteristics change owing to its aging in soil. Studies have shown that some aged biochar is hazardous to plants and soil microbiota. Earthworms are well-known soil ecosystem engineers; nevertheless, the toxic effects of aged biochar on them (vermitoxicity) are yet unknown, and it is necessary to explore the potential risk factors. Here, a series of soil culture experiments were conducted to systematically examine the vermitoxicity of aged biochar at various levels utilizing the earthworm Eisenia fetida and corncob biochar.. Acute toxicity bioassays were also used to evaluate several potential harm factors utilizing modified aged biochar/leaching solutions. The findings showed that both fresh and aged biochar might have adverse effects on earthworms, and that aged biochar was more toxic than fresh biochar with LC₅₀s reduced to 6.89%. Specifically, aged biochar caused earthworm death, growth inhibition with a maximum of 36.6%, and avoidance with 100% avoidance at the application rates of 2% at the individual-behavioral level. At the cellular and physiological-biochemical levels, aged biochar damaged coelomocyte lysosomal membrane stability, disrupted antioxidant enzyme activities, and improved the malondialdehyde (MDA) content in earthworms. Heat-treated and pH-modified aged biochar exhibited less acute toxicity on earthworms than aged biochar, whereas aqueous and acetone extracts showed weak vermitoxicity. As a result, earthworms may be harmed by volatile organic compounds (VOCs), an improper pH, and aqueous and acetone extracts. Additionally, the range of neural red retention times (NRRTs) was reviewed as ∼20-70 min mostly. This study, as far as we know, is the first to evaluate the vermitoxicity of aged biochar and its potential damage factors. The results may enhance our understanding of ecological toxicity of biochar, particularly over the long term, and lead to the development of application standards for biochar amendments to the soil.

Antibacterial Activity of Culinary-Medicinal Polypore Mushroom Lentinus tigrinus (Agaricomycetes)

Medicinal mushrooms belonging to Lentinus spp. exhibit significant antibacterial activities, but little attention has been paid to their efficacy against the food-borne pathogen, Bacillus cereus. The present study for the first time quantitatively evaluated the antibacterial activity of different extracts from fruiting bodies of a well-authenticated Iranian native strain of medicinal mushroom, Lentinus tigrinus, against Gram-positive spore-forming bacterium B. cereus. The findings revealed that the acetone extract inhibited the growth of B. cereus at concentrations as low as 31.25 μg/ML, while it had no effect against Escherichia coli and Staphylococcus aureus even at 10,000 μg/ML. The rest of the bacteria were also susceptible to the acetone extract at concentrations greater than 5 mg/ML. Antibacterial activities of the methanol-ethyl acetate extract and the hot water extract were significantly weaker than that of the acetone extract, which contained high amounts of total phenols (5.83 ± 0.08 mg GAE/g, dw), while Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of functional groups, such as hydroxyl, carbonyl, amide, and amine. Further studies by scanning electron microscopy (SEM) confirmed obvious changes in the morphology of B. cereus in response to the acetone extract of L. tigrinus. This study may suggest that L. tigrinus could be a good natural source for isolating and purifying antibacterial compounds against B. cereus.

Acetone extracts of three selected plants induce toxicological and biological effects against the house mosquito, Culex pipiens (Diptera: Culicidae)

The biological effect of acetone extracts from three selected plants, Lantana camara, Rhazya astricta, and Citrullus colocynthis, on the egg hatch rate, larvicidal activity, and larval development of Culex pipiens L. was investigated. The egg hatch rate of Cx. pipiens was significantly reduced (P<0.01) when the extracts of L. camara were used. Moreover, the used extracts significantly exhibited a variable larvicidal activity against the Cx. pipiens (P<0.001). The most toxicity was observed when the larvae were treated with the acetonic extract of L. camara, showing different toxicities with lower LC₅₀s at 140.1 ppm after two days and 51.3 ppm after ten days. In this observed time, larvae suffered chronic toxicities (increased mortality with increasing exposure time and sublethal endpoints, such as decreased larvae development) when treated with used plant extracts, leading to 96.7% mortality with L. camara and 91.5% and 85.7% mortalities with C. colocynthis and Rh. stricta, respectively. All concentrations significantly obstructed larvae development, causing significant reductions in both the proportion of pupation (P<0.001) and the emergence of adults (P<.001). The larval development reduction was observed under the L. camara extracts treatment, where only 15.2% and 9.7% of the larvae managed to reach pupal and adult stages, respectively. In conclusion, applying acetone extracts from L. camara to immature mosquito breeding sites may efficiently control mosquitoes to reduce the reliance on insecticides against these disease vectors.

Could acetone O-(4-chlorophenylsulfonyl)oxime be a copper chelating and antioxidative molecule on maize seedlings?

The main purpose of study is to determine if Acetone O- (4-chlorophenylsulfonyl) oxime (AO) has a positive effect on maize seedlings under copper (Cu) stress or not. Seedlings were allocated to following experimental groups: 18-hour distilled water (DW) Control (C), ago 6-hour 0.66 mM AO + later 12-hour DW (AO), ago 6-hour DW + later 12-hour 1 mM Cu (Cu), ago 6-hour 0.66 mM AO + later 12-hour 1 mM Cu (AO + Cu). The results showed that AO + Cu caused approximately three times more copper accumulation compared to Cu treatment. AO and AO + Cu treatments significantly decreased membrane damage and H₂O₂ formation compared to its control. The proline content was significantly increased in AO and AO + Cu compared to its control. While the highest catalase, Guaiacol Peroxidase and superoxide dismutase activity was observed in Cu application, the highest ascorbate peroxidase activity was determined in AO application. It was observed that AO had a protective effect on chlorophyll content and RWC, but a positive effect on carotenoid content could not be determined. In addition, the effects of AO on the content of 17 phenolic substances in maize leaves were determined. In the light of the current findings, AO may prevent the formation of radical compounds.

Acetone application for administration of bioactive substances has no negative effects on longevity, fitness, and sexual communication in a parasitic wasp

Administration of defined amounts of bioactive substances is a perseverative problem in physiological studies on insects. Apart from feeding and injection, topical application of solutions of the chemicals is most commonly used for this purpose. The solvents used should be non-toxic and have least possible effects on the studied parameters. Acetone is widely used for administration of chemical substances to insects, but possible side-effects of acetone application on fitness and behavioral parameters have been rarely investigated. Here we study the effects of acetone application (207 nl) on fitness and sexual communication in the parasitic wasp Nasonia giraulti Darling. Application of acetone had neither negative effects on longevity nor on offspring number and offspring sex ratio of treated wasps. Treatment of females hampered courtship and mating of N. giraulti couples neither directly after application nor one day after. Male sex pheromone titers were not influenced by acetone treatment. Three application examples demonstrate that topical acetone application is capable of bringing active amounts of insect hormones, neuromodulators, and biosynthetic precursors even in tiny insects. We advocate the use of acetone as a convenient, conservative, and broadly applicable vehicle for studying the effects of bioactive substances in insects.

Hold your breath - Differential behavioral and sensory acuity of mosquitoes to acetone and carbon dioxide

Host seeking in the yellow fever mosquito, Aedes aegypti, and the African malaria mosquito, Anopheles coluzzii, relies on specific and generic host-derived odorants. Previous analyses indicate that the behavioral response of these species depends differentially on the presence of carbon dioxide (CO₂) and other constituents in human breath for activation and attraction. In this study, we use a flight tube assay and electrophysiological analysis to assess the role of acetone, a major component of exhaled human breath, in modulating the behavioral and sensory neuronal response of these mosquito species, in the presence and absence of CO₂. When presented alone at ecologically relevant concentrations, acetone increases attraction in Ae. aegypti, but not in An. coluzzii. Moreover, in combination with CO₂, human breath-equivalents of acetone ranging between 0.1 and 10 ppm reproduces a behavioral response similar to that observed to human breath in host-seeking Ae. aegypti, but not in An. coluzzii. Acetone does, however, reduce attraction to CO₂ in An. coluzzii, when presented at a higher concentration of 10 ppm. We identify the capitate peg A neuron of the maxillary palp of both species as a dual detector of CO₂ and acetone. The sensory response to acetone, or binary blends of acetone and CO₂, reflects the observed behavioral output in both Ae. aegypti and An. coluzzii. We conclude that host recognition is contextual and dependent on a combination of ecologically relevant odorants at naturally occurring concentrations that are encoded, in this case, by differences in the temporal structure of the neuronal response. This information should be considered when designing synthetic blends for that optimally attract mosquitoes for monitoring and control.

The role of acetone in the [omim][BF4]-mediated adverse effects on tissues of mussels, human lymphocytes and the fruit fly Drosophila melanogaster

The present study investigated [omim][BF₄]-mediated adverse effects on biological models widely used in toxicological studies. Specifically, mussels of the genus Mytilus, human lymphocytes and fruit flies of the species Drosophila melanogaster, were exposed to [omim][BF₄] at concentrations ranging from micro- to milligrams per liter, with or without the presence of acetone as a carrier solvent and thereafter [omim][BF₄]-mediated adverse effects were analyzed appropriately (stress indices, such as lipid peroxidation byproducts, acetylcholinesterase/AChE activity and micronucleus/MN formation frequency, in mussel gills, Cytokinesis Block Micronucleus/CBMN assay and SMART test in human lymphocytes and fruit flies respectively). LC-MS-TOF analysis was also performed for elucidating [omim][BF₄] mode of action in the presence of the carrier solvent. The results showed the toxic potential of [omim][BF₄], as well as acetone's ability to attenuate [omim][BF₄]-mediated toxicity in almost all cases, probably due to the significant effect of acetone on the hydrophilic-lipophilic character and the viscosity of [omim][BF₄], as well as its interaction and permeability on the cell membranes. The slight involvement of acetone in the attenuation of [omim][BF₄]-mediated genotoxic effects on D. melanogaster could be due to species feeding experimental conditions, thus favoring the induction of antioxidant defense system against the [omim][BF₄]-mediated effects in all cases.

Synergistic effects of sodium ascorbate and acetone to restore compromised bond strength after enamel bleaching

AIM

To evaluate the effect of a new experimental solution containing sodium ascorbate (SA) and acetone on reversing compromised bonding to enamel immediately after bleaching.

MATERIALS AND METHODS

The buccal surface of intact, extracted human premolars (n = 60) was bleached. The teeth were then randomly assigned to 6  groups according to the type of pretreatment applied prior to adhesive procedures: 10% SA in acetone-water solution applied for 1 and 5 min (groups 1 and 2, respectively); aqueous solution of 10% SA applied for 10 min (group 3); 100% acetone applied for 10 min (group 4); no pretreatment (negative control; group 5). An additional group (positive control; group 6) comprised unbleached teeth (n = 12). Two composite microcylinders were bonded on each specimen for evaluation of microshear bond strength (MBS) and failure modes. Data were analyzed using the one-way ANOVA and Tukey's post-hoc and chi-square tests at P = 0.05.

RESULTS

Groups 1 and 2 yielded similar MBS values to groups 4 and 6 (positive control). The mean MBS of groups 3 and 5 (negative control) were similar, and significantly lower than that of the positive control group.

CONCLUSION

The application of 10% SA in an acetone-water solution prior to bonding procedures can restore compromised enamel bond strength to its unbleached state within a clinically acceptable time of 1 min.

Resin-dentin Bond Stability of Experimental 4-META-based Etch-and-rinse Adhesives Solvated by Ethanol or Acetone

PURPOSE

To investigate the influence of 4-META concentration and type of solvent on the degree of conversion (DC%) and resin-dentin bond stability of experimental etch-and-rinse adhesives.

MATERIALS AND METHODS

Four different concentrations of 4-META (12 wt%, 20 wt%, 30 wt%, 40 wt%) were added to a model adhesive system consisting of TEG-DMA (25 wt%), UDMA (20 wt%), HEMA (30 wt%), water (4 wt%), camphorquinone (0.5 wt%), and tertiary amine (0.5 wt%) dissolved in 20% acetone (A12, A20, A30 and A40) or 20% ethanol (E12, E20, E30 and E40). DC% was evaluated by FT-IR spectroscopy. Human molars were wet ground until the occlusal dentin was exposed, the adhesive systems were applied after 37% phosphoric acid etching, and resin composite buildups were incrementally constructed. After storage in distilled water at 37°C for 24 h, the teeth were cut into resin-dentin beams (cross-sectional area 1 mm2). Microtensile bond strength (μTBS) was evaluated after 24 h, 6 months, and 1 year of water storage at 37°C. The failure mode was categorized as adhesive, mixed, or cohesive. Data were analyzed using ANOVA and Tukey's HSD test (α = 0.05).

RESULTS

A12 presented the lowest DC% (p < 0.05). All the other adhesive systems showed statistically similar DC% (p > 0.05). All adhesive systems maintained resin-dentin bond stability after 6 months of water storage, while only A40 and E40 maintained it after 1 year.

CONCLUSION

Irrespective of the type of organic solvent, the incorporation of high concentrations of 4-META (40 wt%) improved the resin-dentin bond stability of the experimental etch-and-rinse adhesive systems over a period of 1 year.

IN VITRO AND IN VIVO EVALUATION OF ANTIMICROBIAL AND ANTIOXIDANT POTENTIAL OF STEVIA EXTRACT

BACKGROUND

The current trend globally is the utilization of natural products as therapeutic agents given its minimum side effects. The leaves of Stevia contain several active ingredient compounds such as rebaudioside. Stevia extract have been used for many purposes. Active oxygen radicals can induce base modifications, DNA breakage, and intracellular protein crosslink's. This study was done to evaluate the potential of stevia extract as antibacterial and antioxidants actions.

MATERIALS AND METHODS

Antibacterial activity of different extracts of stevia was tested in vitro against different species of bacteria and hepato-protective efficacy was testes in rats injected with CCl4 as hepatotoxic.

RESULTS

Acetone extract exhibited antibacterial activity against selected five bacteria species. The acetone extract suppressed the elevation of serum ALT (p <0.05) and AST (p <0.001) activities induced by CCl4. Animals given stevia extract showed prevention against deleterious effects of CCl4 by lowering lipid peroxidation and enhancement of antioxidant activities as SOD and CAT. The protection trial is better than treatment trial. Total phenolic content of aqueous and acetone extracts were found 30 mg and 85 mg gallic /gm extract respectively. While the total flavonoids were 40 mg and 80 mg quercetin/g respectively. The GC-MS analysis showed that monoterpene and indole are the main components. Aqueous extract don't show any antibacterial activity against the tested strains. The antioxidant properties were attributable to its phenolic content to scavenge free radicals.

CONCLUSION

Acetone extract possess a potent antimicrobial and activity against deleterious effect of CCl4-caused liver damage.

The consequence of biologic graft processing on blood interface biocompatibility and mechanics

Processing ex vivo derived tissues to reduce immunogenicity is an effective approach to create biologically complex materials for vascular reconstruction. Due to the sensitivity of small diameter vascular grafts to occlusive events, the effect of graft processing on critical parameters for graft patency, such as peripheral cell adhesion and wall mechanics, requires detailed analysis. Isolated human umbilical vein sections were used as model allogenic vascular scaffolds that were processed with either: 1. sodium dodecyl sulfate (SDS), 2. ethanol/acetone (EtAc), or 3. glutaraldehyde (Glu). Changes in material mechanics were assessed via uniaxial tensile testing. Peripheral cell adhesion to the opaque grafting material was evaluated using an innovative flow chamber that allows direct observation of the blood-graft interface under physiological shear conditions. All treatments modified the grafts tensile strain and stiffness properties, with physiological modulus values decreasing from Glu 240±12 kPa to SDS 210±6 kPa and EtAc 140±3 kPa, P<.001. Relative to glutaraldehyde treatments, neutrophil adhesion to the decellularized grafts increased, with no statistical difference observed between SDS or EtAc treatments. Early platelet adhesion (% surface coverage) showed no statistical difference between the three treatments; however, quantification of platelet aggregates was significantly higher on SDS scaffolds compared to EtAc or Glu. Tissue processing strategies applied to the umbilical vein scaffold were shown to modify structural mechanics and cell adhesion properties, with the EtAc treatment reducing thrombotic events relative to SDS treated samples. This approach allows time and cost effective prescreening of clinically relevant grafting materials to assess initial cell reactivity.

Structural and Catalytic Characterization of a Fungal Baeyer-Villiger Monooxygenase

Baeyer-Villiger monooxygenases (BVMOs) are biocatalysts that convert ketones to esters. Due to their high regio-, stereo- and enantioselectivity and ability to catalyse these reactions under mild conditions, they have gained interest as alternatives to chemical Baeyer-Villiger catalysts. Despite their widespread occurrence within the fungal kingdom, most of the currently characterized BVMOs are from bacterial origin. Here we report the catalytic and structural characterization of BVMO_AFL838 from Aspergillus flavus. BVMO_AFL838 converts linear and aryl ketones with high regioselectivity. Steady-state kinetics revealed BVMO_AFL838 to show significant substrate inhibition with phenylacetone, which was more pronounced at low pH, enzyme and buffer concentrations. Para substitutions on the phenyl group significantly improved substrate affinity and increased turnover frequencies. Steady-state kinetics revealed BVMO_AFL838 to preferentially oxidize aliphatic ketones and aryl ketones when the phenyl group are separated by at least two carbons from the carbonyl group. The X-ray crystal structure, the first of a fungal BVMO, was determined at 1.9 Å and revealed the typical overall fold seen in type I bacterial BVMOs. The active site Arg and Asp are conserved, with the Arg found in the “in” position. Similar to phenylacetone monooxygenase (PAMO), a two residue insert relative to cyclohexanone monooxygenase (CHMO) forms a bulge within the active site. Approximately half of the “variable” loop is folded into a short α-helix and covers part of the active site entry channel in the non-NADPH bound structure. This study adds to the current efforts to rationalize the substrate scope of BVMOs through comparative catalytic and structural investigation of different BVMOs.

HISTOCHEMICAL DEMONSTRATION OF PHOSPHOLIPASE B (LYSOLECITHINASE) ACTIVITY IN RAT TISSUES

A method has been developed for the histochemical demonstration of phospholipase B (lysolecithinase) of rat tissues. The enzyme attacks lysolecithin with liberation of 1 mole of glycerylphosphorylcholine and 1 mole of fatty acid. The recommended procedure involves use of 6-10 µ frozen sections, fixed in cold calcium-formol and incubated at 37°C in Tris buffered medium at pH 6.6 containing 2.2 x 10–3 M lysolecithin and 1% cobalt acetate. The fatty acid liberated by enzymatic hydrolysis is trapped as a cobalt precipitate and is then converted to a blackbrown precipitate by treatment with dilute ammonium sulfide in cold isotonic saline. Equivalent amounts of fatty acid and glycerylphosphorylcholine are recovered by extraction and analysis of the incubated sections and of the incubation medium, thus proving that lysolecithin hydrolysis occurs under the proposed reaction conditions. Staining is reduced by treating the sections with copper ions, mercury compounds, alcohols, acetone and by heating at 60°C prior to incubation with substrate. Lowering of the pH of the incubation medium has similar effect. These findings are interpreted as evidence of the enzymatic nature of the reaction. Cells exhibiting a positive staining are found in the lamina propria of the intestinal villi and crypts, in the red pulp of the spleen and in the interstitial tissue of lung, liver and thymus. Similar elements are present in bone marrow smears and in leukocyte preparations obtained by peritoneal lavage. The morphologic and staining characteristics of these cells correspond to those of the eosinophilic leukocytes. Physical and chemical agents (x-irradiation corticosteroids) which sharply decrease the number of eosinophils also reduce the number of cells shown histochemically to hydrolyze lysolecithin. A correspondent. diminution of phospholipase B activity of homogenates of the same tissues can be shown in vitro. Differences in tissue distribution and chemical properties distinguish the phospholipase B from less specific esterases and lipases.

Skin barrier modification with organic solvents

The primary barrier to body water loss and influx of exogenous substances resides in the stratum corneum (SC). The barrier function of the SC is provided by patterned lipid lamellae localized to the extracellular spaces between corneocytes. SC lipids are intimately involved in maintaining the barrier function. It is generally accepted that solvents induce cutaneous barrier disruption. The main aim of this work is the evaluation of the different capability of two solvent systems on inducing changes in the SC barrier function. SC lipid modifications will be evaluated by lipid analysis, water sorption/desorption experiments, confocal-Raman visualization and FSTEM images. The amount of SC lipids extracted by chloroform/methanol was significantly higher than those extracted by acetone. DSC results indicate that acetone extract has lower temperature phase transitions than chloroform/methanol extract. The evaluation of the kinetics of the moisture uptake and loss demonstrated that when SC is treated with chloroform/methanol the resultant sample reach equilibrium in shorter times indicating a deterioration of the SC tissue with higher permeability. Instead, acetone treatment led to a SC sample with a decreased permeability thus with an improved SC barrier function. Confocal-Raman and FSTEM images demonstrated the absence of the lipids on SC previously treated with chloroform/methanol. However, they were still present when the SC was treated with acetone. Results obtained with all the different techniques used were consistent. The results obtained increases the knowledge of the interaction lipid-solvent, being this useful for understanding the mechanism of reparation of damaged skin.

Antinociceptive effects of a new sigma-1 receptor antagonist (N-(2-morpholin-4-yl-ethyl)-2-(1-naphthyloxy)acetamide) in two types of nociception

Pain has become an active clinical challenge due its etiological heterogeneity, symptoms and mechanisms of action. In the search for new pharmacological therapeutic alternatives, sigma receptors have been proposed as drug targets. This family consists of sigma-1 and sigma-2 receptors. The sigma-1 system is involved in nociception through its chaperone activity. Additionally, it has been shown that agonist to these receptors promote related sensitisation and pain hypersensitisation, suggesting the possible use of antagonists for sigma-1 receptors as an alternative therapy. The aim of this study was to evaluate the antinociceptive effect of a new sigma-1 receptor antagonist N-(2-morpholin-4-yl-ethyl)-2-(1-naphthyloxy)acetamida (NMIN) in two types of pain (arthritic and neuropathic) and to compare its efficacy and potency with reference drugs. The antinociceptive effects of NMIN were quantitatively evaluated using the pain-induced functional impairment model in the rat and the acetone test in a rat model of neuropathic pain. NMIN (sigma-1 receptor affinity of 324nM) did not show any antinociceptive activity in the arthritic pain model but showed a dose-dependent anti-allodynic effect in neuropathic pain. NMIN showed a similar efficacy compared to the effects obtained with morphine and the sigma-1 antagonist BD-1063. However, these reference drugs showed increased potency compared with NMIN. Our results suggest that sigma-1 receptors may play an important direct role in neuropathic pain but not in arthritic pain, supporting the hypothesis that NMIN may be useful for the treatment of neuropathic pain.

Appetite-enhancing Effects of trans-Cinnamaldehyde, Benzylacetone and 1-Phenyl-2-butanone by Inhalation

Fragrance in the air and odours of foods and drinks are reported to affect feeding behaviours of humans and other animals. Many previous studies focusing on the relationship between fragrance and appetite have described a reduction of food intake by fragrance administration to help prevent lifestyle diseases. Aromatic herbal medicines, such as cinnamon bark and fennel fruit, are considered to have appetite-enhancing effects and they are often blended in stomachics for relief of asitia and gastric distress in Japan. These fragrant herbal medicines contain many essential oils and their fragrances are hypothesised to be active substances. In this study, food intake and the expression of neuropeptide Y and proopiomelanocortin in the hypothalamus after inhalation of fragrant compounds or essential oils were investigated in mice. Food intake was increased 1.2-fold and the neuropeptide Y mRNA expression in the hypothalamus was increased significantly in mice that inhaled trans-cinnamaldehyde, benzylacetone or 1-phenyl-2-butanone, compared with the control group. These compounds might be effective for treating loss of appetite (anorexia) or eating disorders in elderly and infirm people via a non-invasive route of administration, namely, inhalation.

Effects of acetone, acetonitrile, ethanol, methanol and DMSO on cytochrome P450 in rainbow trout (Oncorhynchus mykiss) hepatic microsomes

In vitro impacts of five organic solvents on cytochrome P450 (CYP450) enzyme activity were investigated using hepatic microsomes of rainbow trout. The rates of several CYP450-mediated reactions were investigated at solvent concentrations ranging from 0.01% to 3%. The solvents greatly affected all tested reactions. In at least 0.8% ethanol, 2% methanol or acetone, 1% acetonitrile or 3% dimethyl sulfoxide (DMSO), 7-ethoxyresorufin-O-deethylase (EROD) activity decreased and at 3% acetonitrile or ethanol, it was undetected. At 3%, all tested solvents except methanol reduced 7-benzyloxy-4-trifluoromethylcoumarin-O-debenzylase (BFCOD) activity, but at low concentrations of ethanol (2% and lower) or DMSO (1% and lower), it was induced. This was not seen with the inclusion of a pre-incubation step. p-Nitrophenolhydroxylase (PNPH) activity was not affected at concentrations below 1% DMSO, and at 2% acetonitrile it was reduced, as it was above 1% methanol or 0.5% ethanol. Acetone did not affect PNPH activity with or without a pre-incubation step. In general, the degree of inhibition was similar with and without the pre-incubation step. We conclude that the concentration of organic solvent for solubilizing the substrate and inhibitor in in vitro microsomal studies should be minimized.

Electrophysiological characterization of activation state-dependent Ca(v)2 channel antagonist TROX-1 in spinal nerve injured rats

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TROX-1 exhibits activation state-dependent inhibition of Ca_v2.2 in vitro.

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TROX-1 selectively attenuates neuronal responses to mechanical stimulation.

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Anti-nociceptive effect of TROX-1 dependent on pathophysiological state.

Prialt, a synthetic version of Ca_v2.2 antagonist ω-conotoxin MVIIA derived from Conus magus, is the first clinically approved voltage-gated calcium channel blocker for refractory chronic pain. However, due to the narrow therapeutic window and considerable side effects associated with systemic dosing, Prialt is only administered intrathecally. N-triazole oxindole (TROX-1) is a novel use-dependent and activation state-selective small-molecule inhibitor of Ca_v2.1, 2.2 and 2.3 calcium channels designed to overcome the limitations of Prialt. We have examined the neurophysiological and behavioral effects of blocking calcium channels with TROX-1. In vitro, TROX-1, in contrast to state-independent antagonist Prialt, preferentially inhibits Ca_v2.2 currents in rat dorsal root ganglia (DRG) neurons under depolarized conditions. In vivo electrophysiology was performed to record from deep dorsal horn lamina V/VI wide dynamic range neurons in non-sentient spinal nerve-ligated (SNL) and sham-operated rats. In SNL rats, spinal neurons exhibited reduced responses to innocuous and noxious punctate mechanical stimulation of the receptive field following subcutaneous administration of TROX-1, an effect that was absent in sham-operated animals. No effect was observed on neuronal responses evoked by dynamic brushing, heat or cold stimulation in SNL or sham rats. The wind-up response of spinal neurons following repeated electrical stimulation of the receptive field was also unaffected. Spinally applied TROX-1 dose dependently inhibited mechanically evoked neuronal responses in SNL but not sham-operated rats, consistent with behavioral observations. This study confirms the pathological state-dependent actions of TROX-1 through a likely spinal mechanism and reveals a modality selective change in calcium channel function following nerve injury.

A biomechanical characterisation of acellular porcine super flexor tendons for use in anterior cruciate ligament replacement: investigation into the effects of fat reduction and bioburden reduction bioprocesses

The decellularisation of xenogenic and allogeneic biological grafts offers a promising solution to replacement of the anterior cruciate ligament (ACL). The purpose of this investigation was to determine the biomechanical effects of additional fat reduction and bioburden reduction steps in the decellularisation of porcine super flexor tendon (pSFT). Study 1 investigated the use of acetone or chloroform-methanol as a fat reduction agent. The most effective of these was then carried forward into Study 2, which investigated the use of antibiotics or peracetic acid (PAA) as a bioburden reduction agent. Stress relaxation data was analysed using a Maxwell-Wiechert viscoelastic model and, in addition to classical material properties, the tangent modulus of the toe-region was determined from strength testing data. In both studies, the majority of decellularised groups demonstrated no statistical differences for material properties such as tensile strength and Young's modulus compared to native controls. Different trends were observed for many of the viscoelastic parameters, but also for the tangent modulus in the toe-region indicating a change in performance at low strains. The most severe deviations from the profile of the native tangent modulus were found to occur in Study 2 when PAA was used for bioburden reduction. Classic material properties (E, UTS etc.) are often used to compare the characteristics of native and decellularised tissues, however they may not highlight changes occurring in the tissues at low strains. In this study, this represented the physiological strains encountered by substitute acellular ACL grafts. Acetone was chosen as the fat reduction step whereas, antibiotics was preferable over PAA as a bioburden reduction step.

Effects of catalysts and solvents on liquefaction of Onopordum heteracanthum for production of bio-oils

Milled Onopordum heteracanthum stalks were converted to liquid products in organic solvents (methanol, ethanol and acetone) with (KOH and ZnCl₂) and without catalyst in an autoclave at temperatures of 523, 543 and 563 K. Effects of liquefaction parameters such as catalyst and solvent were investigated. The percentage yields from supercritical methanol, ethanol and acetone conversions were 48.2, 50.4 and 66.2 at 563 K in the non-catalytic runs, respectively. In the catalytic run with ZnCl₂, the highest conversion (70.2%) was obtained in acetone at the same temperature. The obtained liquid products at 563 K were analyzed and characterized by elemental, Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry. 106 different compounds have been identified by GC-MS in the liquid products obtained in methanol at 563 K.

Solvent, drying time, and substrate affect the responses of lone star ticks (Acari: Ixodidae) to the repellents deet and picaridin

Behavioral bioassays remain a standard tool in the discovery, development, and registration of arthropod repellents. Tick repellent bioassays are generally uncomplicated, but their results can be affected by basic variables (e.g., dimensions of testing materials, substrate, timing, temperature) of the assay. Using lone star tick, Amblyomma americanum (L.), nymphs in climbing bioassays, we tested for the effects of substrate, solvent, and drying time on tick responses. In dose-response tests, the widely used repellents N,N-diethyl-3-methyl benzamide (deet) and 1-methyl-propyl-2-(hydroxyethyl)-1-piperidinecarboxylate (picaridin) were applied to filter paper strips and challenged by ticks at 10, 20, 30, 40, and 120 min after application. At 10-min drying time, repellency at the intermediate concentration 500 nmol repellent/cm2 filter paper was significantly lower for ethanol solutions of deet and picaridin (0 and 10% ticks repelled, respectively) than for solutions of deet and picaridin in acetone (96.7 and 76.7% ticks repelled, respectively). Repellency was greatest for both the acetone and ethanol solutions of deet and picaridin when challenged 120 min after application, and at shorter drying times at the highest concentration tested (2,000 nmol compound/ cm2). The repellency of picaridin relative to deet differed at some combinations of solvent and drying time but not others. In dose-response tests using different paper substrates and a drying time of 10 min, both ethanol and acetone solutions of deet differed in repellency, depending on both the paper substrate and the solvent. However, there were no differences in repellency between ethanol and acetone solutions of deet applied to nylon organdy in an in vitro and in an in vivo (fingertip) bioassay. When deet in solution with various proportions of ethanol:water was applied at 2,000 nmol deet/cm2 filter paper, the proportion of ticks repelled decreased as the proportion of water in the test solutions increased. Somewhat similar results were seen for solutions of deet in an acetone solvent. Water absorbed from the atmosphere may affect the efficacy of repellents in solution with anhydrous ethanol. Overall, results obtained from bioassays that differ in seemingly minor ways can be surprisingly different, diminishing the value of comparing studies that used similar, but not identical, methods. Nylon organdy or another similar thin cloth may be preferable to filter papers and copier paper for minimizing solvent-related differences. When a paper substrate is used, acetone may be the more suitable solvent if the solubility of the test compound and other factors allow.

A synthetic approach to novel carvotacetone and antheminone analogues with anti-tumour activity

A synthetic approach to analogues of the terpenoid natural product antheminone A is described which employs (-)-quinic acid as starting material. A key conjugate addition step proved to be unpredictable regarding its stereochemical outcome however the route allowed access to two diastereoisomeric series of compounds. The results of biological assay of the toxicity of the target compounds towards non-small-cell lung cancer cell line A549 are reported.

Batch and multi-step fed-batch enzymatic saccharification of Formiline-pretreated sugarcane bagasse at high solid loadings for high sugar and ethanol titers

Formiline pretreatment pertains to a biomass fractionation process. In the present work, Formiline-pretreated sugarcane bagasse was hydrolyzed with cellulases by batch and multi-step fed-batch processes at 20% solid loading. For wet pulp, after 144 h incubation with cellulase loading of 10 FPU/g dry solid, fed-batch process obtained ~150 g/L glucose and ~80% glucan conversion, while batch process obtained ~130 g/L glucose with corresponding ~70% glucan conversion. Solid loading could be further increased to 30% for the acetone-dried pulp. By fed-batch hydrolysis of the dried pulp in pH 4.8 buffer solution, glucose concentration could be 247.3±1.6 g/L with corresponding 86.1±0.6% glucan conversion. The enzymatic hydrolyzates could be well converted to ethanol by a subsequent fermentation using Saccharomices cerevisiae with ethanol titer of 60-70 g/L. Batch and fed-batch SSF indicated that Formiline-pretreated substrate showed excellent fermentability. The final ethanol concentration was 80 g/L with corresponding 82.7% of theoretical yield.

Conformation transition of Bombyx mori silk protein monitored by time-dependent fourier transform infrared (FT-IR) spectroscopy: effect of organic solvent

The conformation transition from random coil and/or helix to β-sheet of silk protein is the most important step in the formation of silk fiber in nature as well as by artificial spinning. Time-dependent Fourier transform infrared (FT-IR) spectroscopy was used in this research to monitor such a conformation transition process induced by the organic solvents methanol, ethanol, propanol, isopropanol, and acetone. The kinetics of β-sheet formation of regenerated Bombyx mori silk fibroin in these organic solvents was obtained by the Δabsorbance-time curve from the time-dependent difference infrared spectra. The results showed that the conformation transition rate of silk fibroin was methanol > ethanol > acetone > propanol > isopropanol, which is in accordance with the polarity of these organic solvents. In connection with the mechanical properties and morphologies of regenerated silk fibers using these organic solvents as coagulation bath reported in the literature, we may conclude that the conformation transition rate of silk protein in the organic solvent is very important in wet-spinning to produce high-performance regenerated silk fibers.

Juvenile hormone (JH) esterase of the mosquito Culex quinquefasciatus is not a target of the JH analog insecticide methoprene

Juvenile hormones (JHs) are essential sesquiterpenes that control insect development and reproduction. JH analog (JHA) insecticides such as methoprene are compounds that mimic the structure and/or biological activity of JH. In this study we obtained a full-length cDNA, cqjhe, from the southern house mosquito Culex quinquefasciatus that encodes CqJHE, an esterase that selectively metabolizes JH. Unlike other recombinant esterases that have been identified from dipteran insects, CqJHE hydrolyzed JH with specificity constant (k_cat/K_M ratio) and V_max values that are common among JH esterases (JHEs). CqJHE showed picomolar sensitivity to OTFP, a JHE-selective inhibitor, but more than 1000-fold lower sensitivity to DFP, a general esterase inhibitor. To our surprise, CqJHE did not metabolize the isopropyl ester of methoprene even when 25 pmol of methoprene was incubated with an amount of CqJHE that was sufficient to hydrolyze 7,200 pmol of JH to JH acid under the same assay conditions. In competition assays in which both JH and methoprene were available to CqJHE, methoprene did not show any inhibitory effects on the JH hydrolysis rate even when methoprene was present in the assay at a 10-fold higher concentration relative to JH. Our findings indicated that JHE is not a molecular target of methoprene. Our findings also do not support the hypothesis that methoprene functions in part by inhibiting the action of JHE.

Effect of organic-phase solvents on physicochemical properties and cellular uptake of astaxanthin nanodispersions

A simplex centroid mixture design was used to study the interactions between two chosen solvents, dichloromethane (DCM) and acetone (ACT), as organic-phase components in the formation and physicochemical characterization and cellular uptake of astaxanthin nanodispersions produced using precipitation and condensation processes. Full cubic or quadratic regression models with acceptable determination coefficients were obtained for all of the studied responses. Multiple-response optimization predicted that the organic phase with 38% (w/w) DCM and 62% (w/w) ACT yielded astaxanthin nanodispersions with the minimum particle size (106 nm), polydispersity index (0.191), and total astaxanthin loss (12.7%, w/w) and the maximum cellular uptake (2981 fmol/cell). Astaxanthin cellular uptake from the produced nanodispersions also showed a good correlation with their particle size distributions and astaxanthin trans/cis isomerization ratios. The absence of significant (p > 0.05) differences between the experimental and predicted values of the response variables confirmed the adequacy of the fitted models.

Organosolvent pretreatment and enzymatic hydrolysis of rice straw for the production of bioethanol

The present study investigates the operational conditions for organosolvent pretreatment and hydrolysis of rice straw. Among the different organic acids and organic solvents tested, acetone was found to be most effective based on the fermentable sugar yield. Optimization of process parameters for acetone pretreatment were carried out. The structural changes before and after pretreatment were investigated by scanning electron microscopy, X-ray diffraction and Fourier transform infrared (FTIR) analysis. The X-ray diffraction profile showed that the degree of crystallinity was higher for acetone pretreated biomass than that of the native. FTIR spectrum also exhibited significant difference between the native and pretreated samples. Under optimum pretreatment conditions 0.458 g of reducing sugar was produced per gram of pretreated biomass with a fermentation efficiency of 39%. Optimization of process parameters for hydrolysis such as biomass loading, enzyme loading, surfactant concentration and incubation time was done using Box-Benhken design. The results indicate that acetone pretreated rice straw can be used as a good feed stock for bioethanol production.

Changes in host-seeking behavior of Puerto Rican Aedes aegypti after colonization

The effects of colonization on host-seeking behavior of mosquitoes was examined by comparing attraction responses of newly colonized Aedes aegypti (L.) from field-collected eggs in Puerto Rico to that of the Gainesville (Florida) strain, originally from Orlando (Florida) and in colony since 1952. Females from the Orlando and the F0 through F10 generations of the Puerto Rico strain were evaluated using attractant odors in a triple-cage dual-port olfactometer. Two attractant sources were used: odors from the hand of a volunteer and a standard blend of L-lactic acid, acetone, and dimethyl disulfide. Convergence of the percentage of attraction responses occurred around the F4-F6 generations of the Puerto Rico strain. Both the Orlando and Puerto Rico strains exhibited similar responses for tests with the remaining F7-F10 generations. A temporal effect on mosquito responses was observed for both strains regardless of the attractant blend used in tests. This study indicates that Ae. aegypti host-seeking behavior changes significantly over the first four to six generations after introduction into the laboratory, whereas the field-collected strain increases in attraction response until it stabilizes at a new level.

Construction of a novel expression vector in Pseudonocardia autotrophica and its application to efficient biotransformation of compactin to pravastatin, a specific HMG-CoA reductase inhibitor

The novel plasmid vector (pTAOR4-Rev) suitable for gene expression in actinomycete strains of Pseudonocardia autotrophica was constructed from 2 P. autotrophica genetic elements, the novel replication origin and the acetone-inducible promoter. The replication origin was isolated from the endogenous plasmid of strain DSM 43082 and the acetone-inducible promoter was determined by analysis of the upstream region of an acetaldehyde dehydrogenase gene homologue in strain NBRC 12743. P. autotrophica strains transformed with pTAOR4-P450, carrying a gene for cytochrome P450 monooxygenase, expressed P450 from the acetone-inducible promoter, as verified by SDS-PAGE and spectral analysis. The biotransformation test of acetone-induced resting cells prepared from a strain of P. autotrophica carrying pTAOR4 that harbors a compactin (CP)-hydroxylating P450 gene revealed 3.3-fold increased production of pravastatin (PV), a drug for hypercholesterolemia. Biotransformation of CP by the same strain in batch culture yielded PV accumulation of 14.3 g/l after 100 h. The expression vector pTAOR4-Rev and its function-enhancing derivatives provide a versatile approach to industrial biotransformation by Pseudonocardia strains, which can be good hosts for P450 monooxygenase expression.

Improvement of plant protein solubilization and 2-DE gel resolution through optimization of the concentration of Tris in the solubilization buffer

It is important to solubilize acetone-precipitated proteins before isoelectric focusing (IEF) to achieve high resolution 2-DE gels. To resolve the maximum possible number of plant protein spots, we developed an improved solubilization buffer for plant proteins. We demonstrated that the resolution of 2-DE gels increased dramatically as the concentration of Tris-base increased, with maximum solubilization obtained at 200 mM Tris-base (Ly200T). The Ly200T buffer was more effective than the commonly used solubilization buffer containing 40 mM Tris at solubilizing acetone-precipitated plant proteins. Use of the Ly200T buffer to solubilize proteins resulted in an increase in intensity of approximately 30% of plant protein spots in the larger-than-40 kDa region of the gel. The Ly200T buffer also improved the resolution of abundant and basic proteins. Thus, the Ly200T buffer can be used to achieve greater resolution of protein spots in plant proteomics research.

Natural moisturizing factors (NMF) in the stratum corneum (SC). I. Effects of lipid extraction and soaking

Natural moisturizing factor (NMF) is essential for appropriate stratum corneum hydration, barrier homeostasis, desquamation, and plasticity. It is formed from filaggrin proteolysis to small, hygroscopic molecules including amino acids. We hypothesized that common lipid extraction and soaking in water would alter the level of NMF in the upper SC and its biophysical properties. A novel method of measuring and quantifying the amino acid components of NMF is presented. Adhesive tapes were used to collect samples of the stratum corneum (SC) and were extracted with 6mM perchloric acid for analysis by reverse-phase HPLC. HPLC results were standardized to the amount of protein removed by the tapes. An increase in NMF was found with increased SC depth. Also, the combination of extraction and soaking was found to increase NMF loss relative to control or to extraction or soaking alone. Our results indicate that common skin care practices significantly influence the water binding materials in the upper SC. The findings have implications for the evaluation and formulation of skin care products.

Reactivity of Langerhans cells after application of different chemicals--an ultrastructural analysis

The goal of this study was to investigate changes in epidermal Langerhans cells after application of different chemicals (acetone, 60% alcohol, 5% nickel sulphate, iodisole, and 0.1% 2,4-dinitrochlorobenzene) on the skin of volunteers. The skin of eight volunteers was treated with acetone, 60% alcohol, iodisol, 5% nickel sulphate, and 0.1% 2,4-dinitrochlorobenzene (DNCB). After application of DNCB, Langerhans cells (LCs) showed increased accumulation of Birbeck granules (Bgs). Alcohol and nickel sulphate caused alternative changes, mainly cytoplasmic vacuolation, in LCs. Nickel sulphate was even responsible for the disappearance of dendrites. Both chemicals have cytotoxic effects on LCs: cytoplasmic organelles and Bgs disappear and subsequently, the antigen-presenting activity of epidermal LCs is inhibited. We did not found any morphological changes in LCs after application of acetone.

Evaluation for attractiveness of four chemicals to the biting midge, Forcipomyia taiwana (Diptera: Ceratopogonidae)

Four chemicals (1-octen-3-ol [octenol], lactic acid, acetone, and carbon dioxide) were evaluated for their attractiveness to the biting midge, Forcipomyia taiwana. The attractiveness was based on the number of adult biting midges attracted to each chemical. Results showed that the attractiveness of each chemical changed with different release rates. The optimal attractive release rates for octenol, lactic acid, and acetone fell in the range 0.5-0.9 mg/h, 0.2-1.4 mg/h, and 3.4-10.9 mg/h, respectively. The most attractive release rates were 0.7 mg/h, 0.2 mg/h, and 4.8 mg/h, respectively. Octenol, lactic acid, and acetone were evaluated simultaneously but in separate traps, at the best attractive release rate mentioned above to compare their attractiveness efficacies. Octenol was the most attractive to F. taiwana, followed by lactic acid and acetone; however, there was no significant difference between the mean numbers of adults attracted by the 3 attractants. Carbon dioxide (CO2) with release rates of 100, 250, and 500 ml/min showed no differences in attractiveness. When combinations of CO2, octenol, and blue light (BL, lamda max = 405 nm) were evaluated, the number of adults attracted by the treatment of CO2 + BL was the lowest, and that of the CO2 + octenol + BL was the highest.

Skin barrier disruption by acetone: observations in a hairless mouse skin model

To disrupt the barrier function of the skin, different in vivo methods have been established, e.g., by acetone wiping or tape-stripping. In this study, the acetone-induced barrier disruption of hairless mice was investigated in order to establish a reliable model to study beneficial, long-term effects on barrier recovery after topical application. For both treatments (i.e., acetone treatment and tape-stripping) the transepidermal water loss directly after disruption and the subsequent barrier recovery profile were similar. Histological assessment showed significant lower number of corneocyte layers in acetone-treated and tape-stripped skin compared to untreated skin, while there was no statistical difference between the two treatments. Lipid analysis of acetone-treated skin revealed that only small fraction of lipids were extracted consisting of predominantly nonpolar lipids. Importantly, the ratio of the barrier lipids, i.e., cholesterol, free fatty acids and ceramides, remained similar between control and acetone-treated skin. This reflects the undisrupted lipid organization, as determined by small-angle X-ray diffraction measurements: the long-periodicity lamellar phase was still present after acetone treatment. Our results contradict earlier studies which reported no mechanical stratum corneum removal, a substantial extraction of lipids and disruption in lipid organization. In conclusion, our studies demonstrate that barrier disruption due to acetone treatment is mainly due to removal of corneocytes.

Cytokine production from human primary teeth pulp fibroblasts stimulated by different pulpotomy agents

PURPOSE

After exposing the pulp tissue, cytokines are produced that regulate the pulp inflammatory response. The dental literature, however, lacks information on the participation of primary tooth fibroblasts in this process. The purpose of this study was to verify the participation of human primary tooth pulp fibroblasts in the inflammatory process, evaluate the production of interleukin 1 beta (IL-l beta) and interleukin 8 (IL-8) from these cells.

METHODS

Pulpotomy agents were applied as conditioned media on cell cultures in the following groups: (1) negative control; (2) positive control (Lipopolysaccharide -LPS); (3) calcium hydroxide (powder); (4) mineral trioxide aggregate (MTA); (5) adhesive resin; and (6) formocresol. After 24 hours in contact with the cells, the conditioned media were removed, the proteins were extracted from the cells and IL-l beta and IL-8 were quantified by ELISA (Enzyme linked immuno-sorbent assay).

RESULTS

Data were analyzed by analysis of variance (P<0.05) and Tukey's test (P<0.05). It was observed that calcium hydroxide has stimulated the production of IL-l beta, without stimulating IL-8. Conversely, the adhesive resin and formocresol stimulated the production of IL-8, and did not stimulate IL-l beta. MTA stimulated both cytokines in an intermediate level when compared to the other materials.

CONCLUSION

Primary tooth fibroblasts can respond immunologically, and different pulp capping materials can help in this process.

Using acetone as solvent to study removal of anthracene in soil inhibits microbial activity and alters nitrogen dynamics

Acetone is often used as a carrier to contaminate soil with polycyclic aromatic hydrocarbons (PAHs) and then to study the factors that control their removal. Acetone is an organic solvent that might affect soil processes. An alkaline saline (Texcoco soil) and an agricultural soil (Acolman soil) were amended with or without acetone, nitrogen + phosphorus (NP), and contaminated with anthracene at 520 mg/kg soil while emissions of CO2 and N2O and concentrations of NH4+, NO2(-) and NO3(-) were monitored. The CO2 emission rate decreased greater than 10 times in the soils amended with acetone. Emission of N2O decreased 70 times in the Acolman soil amended with acetone and NP and 5 times in the Texcoco soil. The concentration of NH4+ decreased in the unamended Acolman and Texcoco soil but increased when acetone was added in the first and remained constant in the latter. Acetone inhibited the increase in the amount of NO3(-) in the Acolman soil but not in the Texcoco soil. It was found that microbial activity as evidenced by the emission of CO2, nitrification, and production of N2O were inhibited by acetone. The amount of acetone used as solvent should thus be kept to a minimum, but it can be assumed that its effect on soil processes will be temporary, as microorganisms are known to repopulate soil quickly.

Aminoacetone Induces Loss of Ferritin Ferroxidase and Iron Uptake Activities

Aminoacetone (AA) is a threonine and glycine metabolite overproduced and recently implicated as a contributing source of methylglyoxal (MG) in conditions of ketosis. Oxidation of AA to MG, NH4+, and H2O2 has been reported to be catalyzed by a copper-dependent semicarbazide sensitive amine oxidase (SSAO) as well as by copper- and iron ion-catalyzed reactions with oxygen. We previously demonstrated that AA-generated O2*-. and enoyl radical (AA*) induce dose-dependent Fe(II) release from horse spleen ferritin (HoSF); no reaction occurs under nitrogen. In the present study we further explored the mechanism of iron release and the effect of AA on the ferritin apoprotein. Iron chelators such as EDTA, ATP and citrate, and phosphate accelerated AA-promoted iron release from HoSF, which was faster in horse spleen isoferritins containing larger amounts of phosphate in the core. Incubation of apoferritin with AA (2.5-50 mM, after 6 h) changes the apoprotein electrophoretic behavior, suggesting a structural modification of the apoprotein by AA-generated ROS. Superoxide dismutase (SOD) was able to partially protect apoferritin from structural modification whereas catalase, ethanol, and mannitol were ineffective in protection. Incubation of apoferritin with AA (1-10 mM) produced a dose-dependent decrease in tryptophan fluorescence (13-30%, after 5 h), and a partial depletion of protein thiols (29% after 24 h). The AA promoted damage to apoferritin produced a 40% decrease in apoprotein ferroxidase activity and an 80% decrease in its iron uptake ability. The current findings of changes in ferritin and apoferritin may contribute to intracellular iron-induced oxidative stress during AA formation in ketosis and diabetes mellitus.

Techniques of celloidin removal from temporal bone sections

OBJECTIVES

We sought to determine whether the technique of celloidin removal influences the results of immunostaining in celloidin-embedded cochleae.

METHODS

We compared four protocols of celloidin removal, including those using clove oil, acetone, ether-alcohol, and methanol saturated with sodium hydroxide. By optimally fixing our tissue (perfused mice), and keeping constant the fixative type (formalin plus acetic acid), fixation time (25 hours), and decalcification time (ethylenediaminetetraacetic acid for 7 days), we determined whether the technique of celloidin removal influenced the immunostaining results. Six antibodies were used with each removal method: prostaglandin D synthase, sodium, potassium adenosine triphosphatase (Na+,K(+)-ATPase), aquaporin 1, connective tissue growth factor, tubulin, and 200 kd neurofilament.

RESULTS

Clove oil, acetone, and ether-alcohol resulted in incomplete removal of the celloidin, thereby negatively affecting the results of immunostaining. The methanol-sodium hydroxide method was effective in completely removing the celloidin; it produced the cleanest and most reproducible immunostaining for all six antibodies.

CONCLUSIONS

Freshly prepared methanol saturated with sodium hydroxide and diluted 1:2 with methanol was the best solvent for removing celloidin from mouse temporal bone sections, resulting in consistent and reproducible immunostaining with the six antibodies tested.

In vitro antibacterial activity of adhesive systems on Streptococcus mutans

PURPOSE

To evaluate the antibacterial activity of three adhesive systems -- Prime & Bond 2.1 (PB), Clearfil SE Bond (CS) and One Up Bond F (OU) -- on Streptococcus mutans in vitro.

MATERIALS AND METHODS

Adherence and agar disk-diffusion tests were performed. For the adherence testing, 40 human enamel specimens (4 mm2) were sterilized and the adhesive sytems were applied (n = 10). The control group did not receive the application of any adhesive system. Specimens were immersed in brain heart infusion broth (BHI) inoculated with S. mutans standardized suspension (10(6) cells/ml) for 48 h at 37 degrees C and 5% CO2. The number of S. mutans cells adhered to each specimen was evaluated by the plating method on BHI agar. For agar disk-diffusion testing, adhesive disks and disks soaked in distilled water (negative control) or 0.2% chlorexidine (positive control) were incubated with S. mutans for 48 h. The diameters of the zones of bacterial inhibition were measured. Adherence data were transformed in logarithms of base 10 (log10). Data were submitted to Kruskal-Wallis and Student-Neuman-Keuls tests at the 5% level of significance.

RESULTS

The results of the adherence test showed that One Up Bond F (OU) and Clearfil SE Bond (CS) did not differ significantly from one another, but allowed significantly less adherence than Prime & Bond 2.1 (PB) and control [mean log10 (standard deviation) values: PB 6.10 (0.19); CS primer 4.55 (0.98); OU 4.65 (0.54); control group 6.34 (0.27)]. The disk-diffusion test showed no significant difference between OU (diameter in mm: 3.02 +/- 0.13) and CS (3.0 +/- 0.12), but both were significantly more effective in inhibiting bacterial growth than PB (1.0 +/- 0.10).

CONCLUSION

The self-etching systems Clearfil SE Bond and One Up Bond F presented a greater inhibitory effect against S. mutans, also in terms of adherence, than did the conventional system, Prime & Bond 2.1.