Solvent Control Research Articles

The use of propolis for preventing and treating Nosema ceranae infection in western honey bee (Apis mellifera Linnaeus, 1787) workers

The health of western honey bees (Apis mellifera L.) is constantly affected by Nosema ceranae, a microsporidian threat to colonies worldwide. We extracted propolis, a natural product exhibiting antimicrobial properties, from honey bee hives, fed it to worker bees before or after infection with N. ceranae, and determined its ability to protect bees from and treat them after infection. Protection from N. ceranae was tested using newly emerged bees that were group fed (50 bees/group) 50% propolis extract for 2, 4 and 8 d prior to infection with 1 × 105 spores per bee. Treatment of N. ceranae was tested on newly emerged bees that were individually force-fed with 2 µL of 50% (w/v) sucrose solution containing 1 × 105 spores per bee and then treated with 50% propolis in 50% sucrose solution (v/v) at 0, 2, 4 and 8 d post infection (p.i.). Positive (sugar water + N. ceranae), negative (sugar water only), and solvent (ethanol + sugar water) controls were included in both studies. Propolis fed to honey bees for 4 or 8 d before infection was associated with significantly reduced mortality, infectivity, and N. ceranae infection rates compared to the positive controls. Moreover, providing propolis to infected honey bees at d 0, 2, and 4 p.i. significantly reduced bee mortality, infection, and infectivity rates compared to the positive controls and bees treated 8 d p.i. Therefore, propolis extracted from honey bee hives may be a promising alternative approach to antibiotics for protecting colonies from Nosema disease.

Activation of cannabinoid 2 receptors by JWH-133 protects against ovarian ischemia-reperfusion injury in rats

ABSTRACT We investigated the efficacy of activated cannabinoid 2 receptors for alleviating ovarian ischemia-reperfusion injury in rats. Female Wistar albino rats were divided randomly into six groups: ischemia-reperfusion (IRG); ischemia-reperfusion + 0.2 mg/kg JWH-133 (JIRG1), ischemia-reperfusion + 1 mg/kg JWH-133 (JIRG2); ischemia-reperfusion + 5 mg/kg JWH-133 (JIRG3); solvent control, and sham control. Ovarian ischemia was established for 3 h followed by reperfusion for 3 h. Ovarian tissue was investigated using histology, immunohistochemistry and biochemistry. Administration of JWH-133 synthetic cannabinoid reduced nuclear factor kappa-B immunoreactivity as well as TUNEL positivity scores and malondialdehyde levels. These reductions were significant in all cases except for the malondialdehyde levels in the 1 mg/kg JWH-133 group. Activation of cannabinoid 2 receptors by JWH-133 reduced ovarian ischemia-reperfusion injury due to its antioxidant and anti-inflammatory effects.

Protective effects of berberine on senile osteoporosis in mice.

The incidence of osteoporosis is positively correlated with age. Berberine has been reported to treat osteoporosis due to its beneficial actions on bone formation. However, the direct effects of berberine on senile osteoporosis remain unclear. The present study investigated the protective effects of berberine on senile osteoporosis in mice and preliminarily evaluated its potential mechanism. 20-month-old male C57BL/6J mice were used as senile osteoporosis mouse model and treated with strontium ranelate (SR) or berberine or solvent control by daily gavage for 2months. Thereafter, bone mass and microstructure parameters were assessed. Histological staining was performed to identify the osteogenic, adipogenic and osteoclastic activity of bone tissue. Moreover, role of cAMP/PKA/CREB signaling pathway in berberine affecting bone marrow mesenchymal stem cells (BMSCs) differentiation was clarified by enzyme-linked immunosorbent assay and western blot analysis. The results showed that the SR-treated group displayed a high trabecular bone mass phenotype. For mice administrated with berberine, cancellous bone mass was upregulated in a dose-dependent manner, as indicated by gradually increased bone mass, trabecular bone volume fraction and trabecular number. Furthermore, berberine promotes osteogenic and inhibits adipogenic differentiation of BMSCs via cAMP/PKA/CREB signaling. Also, bone resorption effect becomes more obvious with increasing dose of berberine in vitro. The present results suggest that berberine exerts potent bone protective effects by promoting bone formation, inhibiting marrow fat accumulation and bone resorption. This effect may be achieved through cAMP/PKA/CREB signaling pathway.

Developmental co-exposure of TBBPA and titanium dioxide nanoparticle induced behavioral deficits in larval zebrafish

Both tetrabromobisphenol A (TBBPA) and titanium dioxide nanoparticle (TiO2 NP) have widespread commercial applications, resulting in their ubiquitous co-presence in the environment and biota. Although environmental chemicals exist as mixtures, toxicity studies are nearly always conducted with single chemicals. Few studies explore potential interactions of different chemical mixtures. In this study, we employ the sensitive developing nerve system in zebrafish to assess the neurotoxicity of TBBPA/TiO2 NP mixtures. Specifically, zebrafish embryos were exposed to solvent control (0.1% DMSO), 2 μM TBBPA, 0.1 mg/L TiO2 NP, and their mixture from 8 to 120 h post fertilization (hpf), and motor/social behavioral assessments were conducted on embryos/larvae at different developmental stages. Our results showed that TBBPA/TiO2 NP single or co-exposures increased spontaneous movement, decreased touch response and swim speed, and affected social behaviors of light/dark preference, shoaling, mirror attack and social contact. In particular, many of these phenotypes were manifested with higher magnitude of changes from the mixture exposure. These behavioral deficits were also accompanied with increased cell death in olfactory region and neuromasts in the lateral line system, increased ROS in gallbladder, pancreas, liver, and intestine, as well as increased lipid peroxidation and decreased ATP levels in whole larval tissue homogenates. Further, genes coding for key cell apoptosis marker and antioxidant enzyme were significantly upregulated by these two chemicals, in particular to their mixture. Interestingly, the co-presence of TBBPA also increased the mean particle size of TiO2 NP in the exposure solutions and the TiO2 NP content in larval tissue. Together, our analysis suggests that TBBPA/TiO2 NP induced behavioral changes may be due to physical accumulation of these two chemicals in the target organs, and TiO2 NP may serve as carriers for increased accumulation of TBBPA. To conclude, we demonstrated that TBBPA/TiO2 NP together cause increased bioaccumulation of TiO2, and heightened responses in behavior, cell apoptosis and oxidative stress. Our findings also highlight the importance of toxicity assessment using chemical mixtures.

Andiroba oil and nanoemulsion (Carapa guianensis Aublet) reduce lesion severity caused by the antineoplastic agent doxorubicin in mice

Doxorubicin (DOX) is an anthracycline antibiotic used in the fight against many types of cancer. Although it is quite effective for this purpose, its clinical use is limited by its severe side effects, highlighting the relevance of efforts to identify substances that act to minimize these effects. In this work, we sought to verify the ability of andiroba oil (AO) and a nanoemulsion of andiroba oil (AN) to lessen the side effects of DOX. The animals were separated into 7 groups with 6 animals each: mice treated with AO (2000 mg/kg), AN (2000 mg/kg), the antineoplastic agent DOX (40 mg/kg), AO+DOX, AN+DOX and solvent controls was used of negative control (corn oil and nanoemulsion surfactant). AO and AN were administered for 14 consecutive days orally by gavage and on the 13th day, applied DOX by intraperitoneal route (i.p.), in order to evaluate the protective potential of andiroba. The animals were euthanized on the 15th day. Hematological, biochemical, histological, and immunohistochemical parameters were analyzed. Andiroba reduced several aspects of the severity of lesions caused by DOX, decreasing hematotoxicity and the severity of histological changes in the liver and kidneys, and reducing the frequency of apoptotic cell death. In many cases, AN showed greater efficacy than AO alone, reflecting the feasibility of using this nanotechnology to improve the pharmacokinetics of lipid compounds in the body. The study sheds new light on the therapeutic benefits of andiroba and suggests new ways for investigating how the quantity and quality of lipid compounds affect exposed organisms.

The genotoxic effects of perchloroethylene in human peripheral blood lymphocytes and the possible ameliorative role of α-tocopherol.

Perchloroethylene (PCE), also known as tetrachloroethylene, is a commercially important chlorinated solvent commonly used in dry cleaning, textile processing, and metal degreasing industries. According to the available studies, the potential genotoxic impacts of this chlorinated solvent on human beings are still controversial. The present work was carried out to determine the genotoxic effects of PCE on human peripheral blood lymphocytes (PBLs) using chromosome aberrations (CAs) and cytokinesis-block micronucleus (CBMN) tests. Additionally, the antigenotoxic potential of α-tocopherol (α-Toc), a well-known antioxidant agent, on human lymphocytes treated with PCE in vitro was assessed. The cells were exposed for 48 h to PCE (25, 50, 100, and 150 μg/mL) alone as well as in combination with α-Toc (100 μg/mL). The findings of the study suggested that, relative to solvent control, PCE significantly increased the structural CA and MN formation for all concentrations. However, simultaneous treatment of PCE and α-Toc caused a significant reduction of CAs and MNi as compared to cultures treated with PCE alone. Besides, the results showed that PCE has cytotoxic effects on human PBLs as indicated by the significant decrease in mitotic index (MI) and nuclear division index (NDI). Nevertheless, the co-treatment of α-Toc with PCE did not reduce the cytotoxicity of PCE at a significant level. In conclusion, it can be suggested that PCE is genotoxic and cytotoxic in human PBLs, and α-Toc has an antigenotoxic effect on PCE-induced genotoxicity but has no significant effect on the cytotoxicity triggered by PCE.

Odour of domestic dogs infected with Leishmania infantum is attractive to female but not male sand flies: Evidence for parasite manipulation.

Globally visceral leishmaniasis (VL) causes thousands of human deaths every year. In South America, the etiologic agent, Leishmania infantum, is transmitted from an infected canine reservoir to human hosts by the bite of the sand fly vector; predominantly Lutzomyia longipalpis. Previous evidence from model rodent systems have suggested that the odour of infected hosts is altered by the parasite making them more attractive to the vector leading to an increased biting rate and improved transmission prospects for the pathogen. However, there has been no assessment of the effect of Le infantum infection on the attractiveness of dogs, which are the natural reservoirs for human infection. Hair collected from infected and uninfected dogs residing in a VL endemic city in Brazil was entrained to collect the volatile chemical odours present in the headspace. Female and male Lu. longipalpis sand flies were offered a choice of odour entrained from infected and uninfected dogs in a series of behavioural experiments. Odour of uninfected dogs was equally attractive to male or female Lu. longipalpis when compared to a solvent control. Female Lu. longipalpis were significantly more attracted to infected dog odour than uninfected dog odour in all 15 experimental replicates (average 45.7±0.87 females attracted to infected odour; 23.9±0.82 to uninfected odour; paired T-test, P = 0.000). Male Lu. longipalpis did not significantly prefer either infected or uninfected odour (average 36.1±0.4 males to infected odour; 35.7±0.6 to uninfected odour; paired T-test, P = 0.722). A significantly greater proportion of females chose the infected dog odour compared to the males (paired T-test, P = 0.000). The results showed that the odour of dogs infected with Le. infantum was significantly more attractive to blood-seeking female sand flies than it was to male sand flies. This is strong evidence for parasite manipulation of the host odour in a natural transmission system and indicates that infected dogs may have a disproportionate significance in maintaining infection in the canine and human population.

Regulatory effect of mitoQ on the mtROS-NLRP3 inflammasome pathway in leptin-pretreated BEAS-2 cells.

Obese asthma is a phenotype of asthma whose occurrence is gradually increasing in both adults and children. The majority of studies have demonstrated that obesity is a major risk factor for asthma and the effect of obesity on the lungs is considerable. NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome has been previously demonstrated to serve a role in obese asthma mediated by mitochondrial reactive oxygen species (mtROS). The aim of the present in vitro study was to investigate the effect of leptin on airway epithelial cells and the protective effect of the mitochondrial-targeted antioxidant mitoquinone (mitoQ). Human normal bronchial epithelial cell lines BEAS-2 cells were used and divided into 6 groups: Control group (negative control), DMSO group (solvent control), lipopolysaccharide (LPS) group (positive control), LPS + mitoQ group, Leptin group and Leptin + mitoQ group. CCK8 assay was used to establish the optimal concentration and incubation time of the drugs. mitoTracker probe and mitoSOX reagent were used to detect the integrity of mitochondrial membranes and the content of mtROS. mRNA expression levels were detected by reverse transcription-quantitative PCR analysis. It was revealed that the mitochondrial membrane was disrupted in the Leptin group, which recovered after treatment with mitoQ. As a result, the production of mitochondrial reactive oxygen species (mtROS) in the Leptin group was significantly increased (P<0.01), but following treatment with mitoQ, this overproduction of mtROS was significantly decreased to normal levels (P<0.01). Furthermore, the expression levels of NOD-, LRR- and pyrin domain-containing protein 3 NLRP3 and caspase-1 mRNA in the leptin-pretreated BEAS-2 cells were significantly increased compared with those in the control group (P<0.01), while they were decreased following mitoQ treatment (P<0.01). Taken together, these data suggested that leptin may promote airway inflammation partially through upregulating the mtROS-NLRP3 inflammasome signaling pathway in airway epithelial cells and mitoQ may be a potential treatment for obese asthma.

Thymoquinone Increased Expression of CD4CD25Treg in Sprague-Dawley Rats Induced Dimethylbenzanthracene

BACKGROUND: The carcinogen dimethylbenzanthracene (DMBA) is immunotoxic. Thymoquinone, meanwhile, is known to have antioxidant and anti-inflammatory effects. AIM: This study aims to determine the effect of thymoquinone and tamoxifen on the CD4CD25Treg count in Sprague-Dawley (SD) rats induced by DMBA. METHODS: The 50 SD rats were divided into five groups. Group I (normal control) was given standard drinking and food. Group II was given thymoquinone, Group III was given tamoxifen, Group IV was given DMBA, and Group V was given solvent control. Thymoquinone, tamoxifen, and solvent control administration started 2 weeks before DMBA administration and continued during DMBA induction. In the 3rd week, except for the normal group, all groups were created to be induced with 10 × 20 mg/kg body weight of DMBA for 5 weeks. In the 21st week, surgery and data collection were performed. The hematology profile and CD4CD25Treg number were carried out employing a flow cytometer. The difference in the average number of CD4CD25Treg and blood cells between groups was analyzed with one-way analysis of variance RESULTS: The results revealed that DMBA induction reduced the number of erythrocytes, HB levels, platelet counts, and leukocyte counts (p &lt; 0.05). The administration of thymoquinone and tamoxifen reduced the hematopoiesis effect of DMBA. The thymoquinone and tamoxifen group had a higher number of CD4CD25Treg and leukocytes than the DMBA group (p &lt; 0.05). CONCLUSION: There was no difference in the average CD4CD25Treg, leukocyte count, lymphocyte count, and monocyte count between the thymoquinone and the tamoxifen groups (p &gt; 0.05).

Whiptail lizards (Aspidoscelis exsanguis) recognize invertebrate prey via cuticular hydrocarbons

AbstractCuticular hydrocarbons (CHCs) present on the surface of arthropods are important mediators of both intraspecific and interspecific interactions. They are known to be important chemical cues that help predatory arthropods locate prey, yet less is known about if and how vertebrate insectivores use these nearly ubiquitous chemical cues. We examined behavioral responses of insectivorous lizards (Aspidoscelis exsanguis) to the CHCs of three different species of arthropod prey (crickets, ants, and spiders). We presented cotton swabs with either extracted CHCs or a solvent control to determine if lizards respond to CHCs in the absence of visual cues of prey. We found that CHCs not only increased the frequency of chemosensory behaviors performed by predatory lizards, but that they also elicit feeding‐like behavior from lizards (e.g., biting at the cotton swabs). These results indicate that lizards not only respond to arthropod CHCs, but that they are sufficient for prey‐recognition by our chosen lizard species. This finding lays the ground work for future studies to investigate the precise compounds that are used by foraging lizards, and how the chemical communication systems of arthropods respond to selection exerted by vertebrate predators.

Identifying Toxicologically Significant Compounds in Urban Wildfire Ash Using In Vitro Bioassays and High-Resolution Mass Spectrometry.

Urban wildfires may generate numerous unidentified chemicals of toxicity concern. Ash samples were collected from burned residences and from an undeveloped upwind reference site, following the Tubbs fire in Sonoma County, California. The solvent extracts of ash samples were analyzed using GC- and LC-high-resolution mass spectrometry (HRMS) and using a suite of in vitro bioassays for their bioactivity toward nuclear receptors [aryl hydrocarbon receptor (AhR), estrogen receptor (ER), and androgen receptor (AR)], their influence on the expression of genetic markers of stress and inflammation [interleukin-8 (IL-8) and cyclooxygenase-2 (COX-2)], and xenobiotic metabolism [cytochrome P4501A1 (CYP1A1)]. Genetic markers (CYP1A1, IL-8, and COX-2) and AhR activity were significantly higher with wildfire samples than in solvent controls, whereas AR and ER activities generally were unaffected or reduced. The bioassay responses of samples from residential areas were not significantly different from the samples from the reference site despite differing chemical compositions. Suspect and nontarget screening was conducted to identify the chemicals responsible for elevated bioactivity using the multiple streams of HRMS data and open-source data analysis workflows. For the bioassay endpoint with the largest available database of pure compound results (AhR), nontarget features statistically related to whole sample bioassay response using Spearman's rank-order correlation coefficients or elastic net regression were significantly more likely (by 10 and 15 times, respectively) to be known AhR agonists than the overall population of compounds tentatively identified by nontarget analysis. The findings suggest that a combination of nontarget analysis, in vitro bioassays, and statistical analysis can identify bioactive compounds in complex mixtures.

Cyclopamine Reduces the Growth of Endometrial Carcinoma and Hedgehog Pathway Proteins in a Xenograft Mouse Model

Endometrial carcinoma is a frequently occurring malignancy of the female reproductive tract. Previous investigations have implicated the Hedgehog signaling pathway, including the smoothened (Smo) receptor, in tumor progression. Here, we established a nude mouse xenograft model of endometrial cancer to investigate the effect of the Smo receptor antagonist cyclopamine on the growth of endometrial carcinoma. Mice were randomly sorted into two groups receiving 0.2 mL/mouse every other day of either cyclopamine (20 mg/mL) or solvent (control). The growth of the mice was observed for 18 days. Then, mice were euthanized, tumors were removed and weighed, and tumor volume inhibition rate (VIR) and weight inhibition rate (WIR) were calculated. Smo, Gli1, and Gli2 mRNA expression was measured in tumor tissues by RT-PCR, and Vascular endothelial growth factor (VEGF) and CD31 were detected by immunohistochemistry. We found that cyclopamine treatment reduced the tumor growth rate and significantly reduced the volumes and weights of the transplanted tumors compared with those of the controls. Furthermore, the transplanted tumors of cyclopamine-treated mice possessed lower expression levels of Smo, Gli1, and Gli2, and displayed a lower positive expression of VEGF and CD31. Thus, the Smo receptor antagonist cyclopamine inhibited transplanted tumor growth in nude mice with endometrial carcinoma, which is likely connected with cyclopamine downregulation of Smo, Gli1, and Gli2 mRNA expression that promote angiogenesis.

Co and Zn Metal Phthalocyanines with Bulky Substituents: Anticancer, Antibacterial Activities and Their Inhibitory Effects on Some Metabolic Enzymes with Molecular Docking Studies

In this study, we reported the synthesis of new cobalt and zinc phthalocyanine compounds with ((ethylenediamine-N,N’,N’-triacetic acid-N-2-ethyl)oxy) (ETAEO) substituted groups. Characterization studies and anticancer properties of both synthesized compounds were determined as well. The inhibitory effects of these complexes on some metabolic enzymes were examined and it was observed that the enzymes inhibited by complex molecules at the micromolar levels. In addition, the active sites of the enzymes were determined by molecular modeling programme for screening the enzyme-inhibitor interactions. The molecular docking method was used to calculate the interactions of molecules with enzymes. Also, human prostate and breast cancer cell lines (PC-3 and MCF-7) were used to determine the anticancer properties of the complexes. All doses of the tetrakis (ETAEO) phthalocyaninato Cobalt II (1) did not show any significant changes in PC-3 cell viability, but significantly reduced in MCF-7 cell viability. Similarly, all doses of the tetrakis (ETAEO) phthalocyaninato zinc II (2) significantly reduced MCF-7 cell viability compared to the control and solvent control groups. According to the enzyme inhibition studies, both complexes showed the best inhibition effects for α-Glycosidase enzyme with 125.85 ± 30.35 µM and 165.30 ± 27.18 µM Ki values.

Solvent effects in hydroformylation of long-chain olefins

With the increasing concern about climate change, a transformation of chemical processes from petrochemicals towards renewable, sustainable feedstock is indispensable. This transition, however, requires a careful assessment of the transferability of kinetic and thermodynamic data and reaction mechanisms. Here, the rhodium-catalyzed hydroformylation reaction of a long chain olefin (1-decene) from renewable resources with synthesis gas (CO/H2) is investigated. The bidentate phosphite ligand (BiPhePhos) shows a high degree of selectivity towards the desired n-aldehyde. This selectivity can be rationalized by kinetic discrimination at the branching point, i.e. the transition state of the hydride insertion step. Formation of the iso-aldehyde is kinetically and thermodynamically discriminated. The complex multi-step reactions of the desired hydroformylation reaction pathway with respect to the side-reactions such as olefin isomerization and hydrogenation are elucidated in detail. The solvent effects of a mixed polar/non-polar thermomorphic solvent system (DMF/dodecane) on chemical equilibria and activation energies were investigated using the COSMO-RS solvent model. Solvent screening for the overall rate-determining step gives a perspective as to solvent control of the process.

Suppression of Kv1.1 Channel Activity by Beta-Amyloid Peptides Involves both Intracellular Calcium-Signaling and Direct Peptide-Peptide Interactions

Past studies indicate that Aβ's role(s) in Alzheimer's disease (AD) pathogenesis involves disruption of Ca2+ homeostasis, synaptic communication, and impairment of learning- and memory-related synaptic plasticity [e.g., hippocampal LTP]. The mechanism(s) underlying these effects are still unclear. Because Kv1.1 (and related) channels are activated during an action potential, regulate depolarization-produced Ca2+ influx, and inhibition of Kv1 channels can be neurotoxic, we have speculated that Aβ-suppression of Kv1 channels could contribute to AD pathology. The bath application of either Aβ(1-42) or “core” peptide Aβ(25-35) produced 40-50% suppression of macroscopic Kv1.1 current within 30 m (murine Kv1.1 channels expressed in Xenopus oocytes). Little or no suppression was produced by reverse peptide Aβ(40-1) or solvent control. Strong suppression of Kv1.2 channels by Aβ(1-42) was also observed. The suppression of Kv1.1 by Aβ(1-42) was partially dependent on intracellular Ca2+ and PP2B, showing only ∼25% reduction when cells were loaded with BAPTA-AM or exposed to the PP2B-inhibitor cyclosporine A (CsA). Membrane capacitance measurements and Western Blot analyses failed to detect any Aβ(1-42)-produced endocytosis of Kv1.1 channels, in contrast to clear endocytosis when large increases in intracellular calcium were produced by the ionophore A23187. Aβ-suppression of Kv1.1 involved both PP2B-dephosphorylation and direct protein-protein interaction of Aβ with Kv1.1 subunits. Exposure of the intracellular face of Kv1.1 channels in ripped-off oocyte patches to either purified catalytically-active PP2B, or Aβ(1-42), produced gradual reductions in p(open), followed by abrupt disappearance of Kv1.1 activity. The collective results from additional single-channel studies [involving “tip-dip”, and black lipid membranes (BLMs)] showed that direct application of Aβ peptides to individual Kv1.1 channels reduced channel activity, whether applied intra- or extra-cellularly. The suppressions produced by the shorter core fragment, Aβ(25-35), were clear but generally weaker than Aβ(1-42).

Simulation and Techno-economic Analysis of a CO2 Capture Scheme for Combustion Processes

Literature search has revealed that most post-combustion CO2 capture processes available to power plants are hinged on sorption technologies (chemical absorption and desorption) which are cost and energy-intensive. The colossal cost of solvents used for the absorption of CO2, the high energy requirements for the absorption & solvent recovery processes, plant design & control related complications, and environmental concerns about the solvents are some of the challenges associated with this option of post-combustion CO2 capture approach which is widely being adopted to mitigate CO2 emissions from power plants. In this study, the capture of CO2 from flue gas by exploring the concept of change of state of matter, which is essentially a physical approach to CO2capture, is presented as an alternative to the typical methods in the industry.

Effect of Leaf Maturity on Host Habitat Location by the Egg-Larval Parasitoid Ascogaster reticulata.

Adoxophyes honmai, a serious pest of tea plants, prefers to lay eggs on mature tea leaves rather than young leaves. Here, we examined a hypothesis that Ascogaster reticulata, an egg-larval parasitoid of A. honmai, increases the likelihood of encountering host egg masses by searching mature tea leaves when host-derived cues are not available. In a dual-choice bioassay using a four-arm olfactometer, A. reticulata preferred odor from intact, mature leaves versus young leaves. Based on volatile analysis with gas chromatography-mass spectrometry (GC-MS), we identified 5 and 10 compounds from mature and young leaf volatiles, respectively. The 5 components in the extract from intact mature leaves included (Z)-3-hexenyl acetate, (E)-β-ocimene, linalool, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), and methyl salicylate. When each individual compound, or quaternary and quintenary blends of them, ratios of which were adjusted to match those of mature leaf volatiles, were provided, parasitoids preferred the full mixture and the quaternary blend devoid of DMNT to the solvent control. Methyl salicylate, one of the components of preferred blends, was not detected among young leaf volatiles. We concluded that the volatile composition of tea leaves changes, depending on their maturity, and that this composition affects foraging behavior of the parasitoid, which is closely related to the host herbivore's oviposition preference.

A model for dynamical solvent control of molecular junction electronic properties

Experimental measurements of electron transport properties of molecular junctions are often performed in solvents. Solvent-molecule coupling and physical properties of the solvent can be used as the external stimulus to control the electric current through a molecule. In this paper, we propose a model that includes dynamical effects of solvent-molecule interaction in non-equilibrium Green's function calculations of the electric current. The solvent is considered as a macroscopic dipole moment that reorients stochastically and interacts with the electrons tunneling through the molecular junction. The Keldysh-Kadanoff-Baym equations for electronic Green's functions are solved in the time domain with subsequent averaging over random realizations of rotational variables using the Furutsu-Novikov method for the exact closure of infinite hierarchy of stochastic correlation functions. The developed theory requires the use of wideband approximation as well as classical treatment of solvent degrees of freedom. The theory is applied to a model molecular junction. It is demonstrated that not only electrostatic interaction between molecular junction and solvent but also solvent viscosity can be used to control electrical properties of the junction. Alignment of the rotating dipole moment breaks the particle-hole symmetry of the transmission favoring either hole or electron transport channels depending upon the aligning potential.

Evaluation of a novel animal milk oligosaccharide biosimilar: macronutrient digestibility and gastrointestinal tolerance, fecal metabolites, and fecal microbiota of healthy adult dogs and in vitro genotoxicity assays.

Milk oligosaccharides (MO) are bioactive compounds in mammalian milk that provide health benefits to neonates beyond essential nutrients. GNU100, a novel animal MO biosimilar, was recently tested in vitro, with results showing beneficial shifts in microbiota and increased short-chain fatty acid (SCFA) production, but other effects of GNU100 were unknown. Three studies were conducted to evaluate the safety, palatability, and gastrointestinal (GI) tolerance of GNU100. In study 1, the mutagenic potential of GNU100 was tested using a bacterial reverse mutation assay and a mammalian cell micronucleus test. In study 2, palatability was assessed by comparing diets containing 0% vs. 1% GNU100 in 20 adult dogs. In study 3, 32 adult dogs were used in a completely randomized design to assess the safety and GI tolerance of GNU100 and explore utility. Following a 2-wk baseline, dogs were assigned to one of four treatments and fed for 26 wk: 0%, 0.5%, 1%, and 1.5% GNU100. On weeks 2, 4, and 26, fresh fecal samples were collected to measure stool quality, immunoglobulin A, and calprotectin, and blood samples were collected to measure serum chemistry, inflammatory markers, and hematology. On weeks 2 and 4, fresh fecal samples were collected to measure metabolites and microbiota. On week 4, total feces were collected to assess apparent total tract macronutrient digestibility. Although revertant numbers were greater compared with the solvent control in tester strain WP2uvrA(pKM101) in the presence of metabolic activation (S9) in the initial experiment, they remained below the threshold for a positive mutagenic response in follow-up confirmatory tests, supporting that GNU100 is not mutagenic. Similarly, no cytotoxicity or chromosome damage was observed in the cell micronucleus test. The palatability test showed that 1% GNU100 was strongly preferred (P < 0.05; 3.6:1 consumption ratio) over the control. In study 3, all dogs were healthy and had no signs of GI intolerance or illness. All diets were well accepted, and food intake, fecal characteristics, metabolite concentrations, and macronutrient digestibilities were not altered. GNU100 modulated fecal microbiota, increasing evenness and Catenibacterium, Megamonas, and Prevotella (SCFA producers) and reducing Collinsella. Overall, the results suggest that GNU100 is palatable and well-tolerated, causes no genotoxicity or adverse effects on health, and beneficially shifts the fecal microbiota, supporting the safety of GNU100 for the inclusion in canine diets.

Evaluation of the anti-ulcer activity of seeds of Syzyzium cumini on experimental animal models

Syzyzium cumini (Myrtaceae) is an evergreen tropical tree mostly found in South East Asia. Extracts of fruits and seeds are extensively used in the treatment of diabetes. Other folkloric uses include treatment of cold, cough, fever, skin problem and genitourinary tract ulcer. The present study evaluated the anti-ulcer activity of the seeds of S. cumini against different ulcer models in rats. The anti-ulcer activity of the methanol extract and ethyl acetate fraction of methanol extract of S. cumini seed was evaluated in ethanol, pylorus ligation, Aspirin + pylorus ligation and stress-induced gastric ulcer model. The study biomarkers used were gastric volume, pH, ulcer index and free acidity. The extract and fraction at the dose level of 200 mg/kg caused a significant (P <0.05) reduction in the ulcer index, free acidity while there was an increase in the pH value of the test in comparison to the solvent control group. Experimentally, it was observed that animals who received ethyl acetate fraction had relatively improved protection of gastric ulcer as demonstrated by different biomarkers. The present study showed that the ethyl acetate fraction of methanol extract of S. cumini seed possesses potential anti-ulcer activity. This may be due to a linear relationship between the antioxidant value of the seeds as reported earlier by several authors due to rich in phenolic compounds, which in turn is responsible for mucosal cytoprotection of the stomach and hence, participate in the enhancement of mucosal defence mechanism.