Therapeutic use of phage cocktail for controlling Escherichia coli O157:H7 in gastrointestinal tract of mice

To investigate the therapeutical use of phage mixture for controlling gastrointestinal Escherichia coli O157:H7 cells, in vitro and in vivo experiments were conducted. Three phages, SP15, SP21, and SP22 were selected from 26 phage stock screened from feces of stock animals and sewage influent. Addition of single or binary phage to the E. coli cell batch-culture reduced the turbidity of the culture. However, reascend of the turbidity due to the appearance of phage resistance cell was observed. On the other hand, addition of three phage mixture (SP15-21-22) did not produce reascend of culture turbidity under aerobic condition. Under anaerobic condition, slight reascend of culture turbidity was observed after SP15-21-22 addition. Chemostat continuous culture was operated under anaerobic condition to optimize the titer of phage cocktail and frequency of the addition for controlling E. coli cells. Five-log decrease of E. coli cell concentration after addition of phage cocktail of 10(9) Plaque forming unit (PFU)/ml was observed. However, reascend of cell concentration was observed after 1 d incubation. Repeated addition of phage cocktail was effective to reduce the cell concentration. Suspension of phage cocktail in the buffer containing 0.25% CaCO3 neutralized 9 times much more buffer of pH 2. Based on this in vitro experiment, phage cocktail (SP15-21-22) suspended in the buffer containing 0.25% CaCO3 was orally administrated to the mice in which E. coli O157:H7 cells was administrated in 2-d advance. E. coli and phage concentration in the feces was monitored for 9 d after phage addition. High titer of phage was detected in the feces when the phage cocktail administrated daily. E. coli O157:H7 concentration in the feces has been reduced according to the time period. However, difference of E. coli concentration in the feces of mice administrates with phage and in the control mice without phage addition became slight after 9-d test period. High titer of the phage settled down in the gastrointestinal tracts and reduced the concentration of E. coli cell. Repeated oral administration of SP15-21-22 was effective for rapid evacuation of E. coli O157:H7 from the feces and gastrointestinal tract of mice.     

Yerba-mate (Ilex paraguariensis) extract prevents ethanol-induced liver injury in rats

Ethanol metabolism-associated oxidative stress contributes to the pathogenesis of alcoholic liver disease. We examined the effect of a Mate tea extract on ethanol-induced liver injury in vitro and in vivo models. Isolated hepatocytes were incubated with ethanol. An extract of Yerba-Mate tea (EMT) was added to the cultures simultaneously with ethanol. EMT treatment suppressed the ethanol-induced increase in cell death by inhibiting cytochrome p450 2E1 (CYP2E1) activity, which is related to the production of reactive oxygen species. Furthermore, we examined the effects of EMT on serum transaminase activity, and the progression of liver fibrosis in rats treated with ethanol and CCl₄. Rats were fed a diet that included 0.005% or 0.02% EMT or no EMT. For a period of 3 weeks, the animals were provided drinking water containing 5% ethanol and were also treated with carbon tetrachloride (CCl₄) (0.1 ml/kg of body weight). EMT treatment suppressed plasma ALT and AST activities in the ethanol- and CCl₄-treated rats. EMT treatment also decreased CYP2E1 expression and increased ADH expression in the ethanol- and CCl₄-treated rats. EMT treatment fully protected the rats against ethanol- and CCl₄-induced liver injury. These results suggest that EMT may serve as a candidate for preventing ethanol-induced liver injury.     

Growth inhibitory effects of anthranilic acid and its derivatives against Legionella pneumophila

Legionella pneumophila is the principal etiologic agent of Legionnaires' disease. We found that the growth of L. pneumophila was markedly inhibited by its own cell lysate and the inhibitory effect was abolished by heat-treatment of the lysate. The genomic library of L. pneumophila was constructed in Escherichia coli and screened to determine the gene involved in the growth inhibition. A clone harboring the gene encoding anthranilate synthase (TrpE), which is involved in tryptophan biosynthesis, exhibited an inhibitory effect on the growth of L. pneumophila. Anthranilic acid exogenously added also exhibited antibacterial activity against L. pneumophila. A series of single-gene-knockout mutants of L. pneumophila lacking tryptophan synthesis genes were constructed and assessed for their susceptibility to anthranilic acid. Although the growth of mutants deficient in anthranilate phosphoribosyltransferase (TrpD) and N-(5'-phosphoribosyl)anthranilate isomerase (TrpF) was not affected by exogenous anthranilic acid, the indole-3-glycerophosphate synthase (TrpC) deficient mutant exhibited an increased susceptibility compared with the parent strain. These observations strongly indicate that 1-(2-carboxyphenylamino)-1'-deoxyribulose-5'-phosphate (CPADR-5'-P), which is an intermediate of tryptophan synthesis from anthranilic acid, is responsible for the growth inhibition of L. pneumophila.     

Selective conversion of glucose into lactic acid and acetic acid with copper oxide under hydrothermal conditions

Biomass as a source for chemicals production attracts growing attention due to the decreasing storage of fossil fuels and global warming caused by emission of CO₂. In this study, conversion of glucose with copper oxide (CuO) was studied under alkaline hydrothermal conditions using a batch reactor and continuous flow reactor. CuO, as an oxidant, greatly improves the yields of lactic acid (LA) and acetic acid from glucose and was reduced into Cu₂O and Cu. Selective production of LA with the highest yield of 59% and acetic acid with the highest yield of 32% can be achieved by controlling reaction time, temperature, and addition of CuO. A possible mechanism of conversion of glucose with CuO was proposed. © 2012 American Institute of Chemical Engineers AIChE J, 59: 2096–2104, 2013     

Gas adsorption on activated carbons from PET mixtures with a metal salt

Activated carbons were prepared from carbonized PET by steam activation via pretreatment by mixing PET with a metal salt [Ca(NO₃)₂·4H₂O, Ca(OH)₂, CaCO₃, ZnO, and AlNH₄(SO₄)₂·12H₂O], and with acid treatment after carbonization. The porous properties of the activated carbons were determined by the nitrogen adsorption method. The adsorption isotherms of CO₂, C₂H₆, nC₄H₁₀ and iC₄H₁₀ at 298 K on the prepared activated carbons were measured to determine practical applications and to obtain a better understanding of the porous structure of the prepared carbons. Steam-activated carbons via pretreatment have a larger mesoporosity than carbons with no pretreatment. The metal salt used in the pretreatment for steam activation has no influence on the microporous structure, but it does influence the mesoporous structure of the prepared carbons. Activated carbons prepared via pretreatment show a large adsorption capacity for nC₄H₁₀ and iC₄H₁₀. These carbons are suitable as adsorbents for canisters, etc. Application of the potential theory to adsorption data for the prepared carbons suggests that the pretreatment contributes to the formation of pores larger than 0.50 nm at high burnoff.     

Synthesis Method for Thiosulfonate and Report of Its Insecticidal Activity in Anagasta kuehniella (Lepidoptera: Pyralidae)

Insect pests have caused economic losses valued at billions of dollars in agricultural production. Anagasta kuehniella (Zeller), the Mediterranean flour moth, is of major economic importance as a flour and grain feeder and is often a severe pest in flourmills. This study provides a suitable route for the direct preparation of thiosulfonates 2 and 3 from thiols, under mild conditions, with good yields; these thiosulfonates were tested for their regulatory effect on insect growth. The chronic ingestion of thiosulfonates resulted in a significant reduction in larval survival and weight. In addition, the tryptic activity of larvae was sensitive to these thiosulfonates. Results suggest that thiosulfonates 2 and 3 have a potential antimetabolic effect when ingested by A. kuehniella. The use of AgNO₃/BF₃·OEt₂ and Al(H₂PO₄)₃/HNO₃ provides a suitable route for the direct preparation of thiosulfonates from thiols under mild conditions with good yields. These thiosulfonates were toxic for A. kuehniella larvae, suggesting their potential as biotechnological tools.     

The Effect of Alkyl Substituents on Actinide and Lanthanide Extraction by Diglycolamide Compounds

The effect of the alkyl substituents on amidic N atoms in diglycolamide (DGA) compounds on solvent extraction has been investigated. The solubility in water and n-dodecane, lanthanide loading capacity, and distribution ratios (D) of lanthanides and actinides for various DGA compounds are reported. DGA derivatives with short alkyl chains, for example, methyl and ethyl groups, are very water soluble, while DGA derivatives with long alkyl chains, for example, octyl (TODGA), decyl (TDDGA), dodecyl (TDdDGA), and 2-ethylhexyl (TEHDGA) group are moderately soluble in n-dodecane. DGA derivatives with phenyl substituents have very low solubility in both aqueous and organic solvents, which suggests that these compounds will not be suitable for solvent extraction applications in the HNO₃/n-dodecane systems. The lanthanide loading capacities of DGA extractants correlate with their alkyl chain lengths according to the following order: TDdDGA > TDDGA > TODGA > TEHDGA. The branched-alkyl-chain DGA derivative (TEHDGA) exhibits both lower D and loading capacity than TODGA. The results of masking-effect and solubility tests indicate that TEDGA is the best actinide masking agent among the water-soluble DGA derivatives tested. Actinide and lanthanide extractions using ten DGA compounds in six diluents (nitrobenzene, 1,2-dichloroethane, 1-octanol, chloroform, toluene, and n-dodecane) are also reported; it was observed that lipophilic DGA derivatives with shorter alkyl chains show higher D values.     

Sex Pheromones of Two Melittini Species, <Emphasis Type="Italic">Macroscelesia Japona</Emphasis> and <Emphasis Type="Italic">M. Longipes</Emphasis>: Identification and Field Attraction

Two Melittini species, Macroscelesia japona and M. longipes (Lepidoptera: Sesiidae), are native to Japan, but occupy different localities as their host plants seldom grow together. The contents of the sex pheromone gland of adult females of both species, obtained after rearing larvae collected from the field, were investigated by gas chromatograph-electroantennogram detection (GC-EAD) and gas chromatograph-mass spectrometry (GC-MS) analyses. Two GC-EAD-active components were found in a crude extract of M. japona female pheromone gland, and identified as (2E,13Z)-2,13-octadecadien-1-ol (E2,Z13-18:OH) and (2E,13Z)-2,13-octadecadienal (E2,Z13-18:Ald). The average ratio of these two components was about 1:10. In the field, M. japona males were attracted to traps baited with E2,Z13-18:Ald alone, but the strongest attraction was observed with a 1:100 mixture of E2,Z13-18:OH and E2,Z13-18:Ald. The same two components were found in extracts of M. longipes females, but in a markedly different ratio. Male M. longipes were attracted most strongly to lures containing a 20:1 mixture of E2,Z13-18:OH and E2,Z13-18:Ald, although some males were also attracted to lures with E2,Z13-18:OH alone. Although the two species do not generally occur in sympatry, our data indicate that, in the event of overlap, cross attraction of the two species is unlikely.     

The first potent subtype-selective retinoid X receptor (RXR) agonist possessing a 3-isopropoxy-4-isopropylphenylamino moiety, NEt-3IP (RXRalpha/beta-dual agonist)

Retinoid X receptor (RXR) agonists (rexinoids) are attracting much attention for their use in treatment of cancers, including tamoxifen-resistant breast cancer and taxol-resistant lung cancer, and metabolic disease. However, known RXR agonists have a highly lipophilic character. In addition, no subtype-selective RXR agonists have been found. We previously reported an RXRalpha-preferential agonist 4-[N-methanesulfonyl-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)amino]benzoic acid (6 a). The RXR agonistic activity is much less than that of well-known RXR agonists. To develop potent, less-lipophilic, and subtype-selective RXR agonists, we created new RXR agonists possessing alkoxy and isopropyl groups as a lipophilic domain of the common structure of well-known RXR agonists. As a result, compounds possessing branched alkoxy groups, 6-[N-ethyl-N-(3-isopropoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IP: 7 a) and 6-[N-ethyl-N-(3-isobutoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IB: 7 c), showed RXR agonistic activity as potent as, or more potent than, the activities of representative RXR agonists. Moreover, NEt-3IP (7 a) was found to be the first RXRalpha/beta-selective (or RXRalpha/beta-dual) agonist. Being potent, less lipophilic, and having RXR subtype-selective activity, NEt-3IP (7 a) is expected to become a new drug candidate and to be a useful biological tool for clarifying each RXR subtype function.     

The adsorption behavior of dialkyl dimethyl ammonium chloride-nonionic surfactant binary systems

From the practical standpoint of fabric softener formulation, a comparative study was made on adsorption behavior toward fabrics of binary systems consisting of di(hydrogenated tallow) dimethyl ammonium chloride (purified Arquad 2HT) and typical polyoxyethylenated nonionic surfactants which are commonly used as auxiliary agents for softeners. Soxhlet extraction of treated fabrics and quantitative analysis by high-performance liquid chromatography (HPLC) gave significant results indicating many of these nonionic surfactants, assumed to be inherently unadsorbable in rinse-cycle treatment, were highly adsorbable even at a high bath ratio by being applied with the water-insoluble cationic surfactant. Moreover, it was also disclosed that the hydrophobic structure of nonionic surfactants is another factor, other than hydrophobicity, determining adsorption. Furthermore, the mechanism of this nonionic adsorption was elucidated on the basis of results of structural analyses of binary dispersions by differential scanning calorimetry (DSC), X-ray diffraction, electron spin resonance spectroscopy (ESR) and transmission electromicroscopy (TEM) in addition to partition measurements of the surfactants into the dispersed and the continuous aqueous phases. It was concluded that the primary driving force for this nonionic adsorption is an association with the lamellar of Arquad 2HT and that the cationic vesicles act as “anchors” in adsorption.