Chia (Salvia hispanica L.) can directly suppress basic ovarian cell functions in two farm animal species and protect ovarian cells from the proliferation-stimulating influence of xylene.

The influence of the functional food plant chia (Salvia hispanica L.) on reproduction functions and its ability to prevent the negative effects of environmental contaminants has not yet been studied. Our study aimed to examine the effect of chia seed extract alone and in combination with xylene on the markers of proliferation, apoptosis and hormones release by cultured bovine and porcine ovarian granulosa cells. The extract of chia reduced all of the measured parameters in bovine and porcine ovarian cells but had no effect on the proliferation of porcine cells. Xylene, stimulated proliferation and IGF-I release and inhibited the release of progesterone and testosterone but not apoptosis of bovine granulosa cells. It promoted proliferation, apoptosis and progesterone output by porcine cells. Chia mitigated the stimulatory effect of xylene on proliferation but not on other parameters in both species. The present results are the first demonstration of a direct effect of chia on basic ovarian cell functions. They confirmed a direct influence of xylene on these functions and found a similar stimulatory action of xylene on bovine and porcine ovarian cell proliferation. The present observations demonstrated species-specific differences in the characteristics of xylene influences on ovarian cell apoptosis and secretory activity. Finally, the present results indicate that chia can be a natural protector against the proliferation-stimulating effects of xylene on ovarian cells in both species.

Antibacterial and antibiofilm potential of Lacticaseibacillus rhamnosus YT and its cell-surface extract.

BACKGROUND: Foodborne pathogens and spoilage bacteria survived in the biofilm pose a serious threat to food safety and human health. It is urgent to find safe and effective methods to control the planktonic bacteria as well as the biofilm formation. Substances with antibacterial and antibiofilm activity found in lactic acid bacteria were mainly metabolites secreted in the cell-free supernatant. Previously, Lacticaseibacillus rhamnosus YT was isolated because its cell pellets displayed distinguished antibacterial activity under neutral conditions. This study aimed to investigate the antibacterial and antibiofilm properties of the L. rhamnosus YT cells and its crude cell-surface extract. RESULTS: The antibacterial activity of the L. rhamnosus YT cells constantly increased with cells growth and reached the peak value after the cells grew into stationary phase. After cocultivation with the L. rhamnosus YT cells, the biofilm formation of B. subtilis and S. enterica was reduced. The antibacterial activity of the L. rhamnosus YT cells was varied along with various culture conditions (carbon sources, nitrogen sources, medium pH and cultural temperatures) and the antibacterial intensity (antibacterial activity per cell) was disproportional to the biomass. Furthermore, the cell-surface extract was isolated and displayed broad antimicrobial spectrum with a bacteriostatic mode of action. The antibiofilm activity of the extract was concentration-dependent. In addition, the extract was stable to physicochemical treatments (heat, pH and protease). The extract performed favorable emulsifying property which could reduce the water surface tension from 72.708 mN/m to 51.011 mN/m and the critical micelle concentration (CMC) value was 6.88 mg/mL. Besides, the extract was also able to emulsify hydrocarbon substrates with the emulsification, index (E24) ranged from 38.55% (for n-hexane) to 53.78% (for xylene). The E24 for xylene/extract emulsion was merely decreased by 5.77% after standing for 120 h. The main components of the extract were polysaccharide (684.63 µg/mL) and protein (120.79 µg/mL). CONCLUSION: The properties of the extract indicated that it might be a kind of biosurfactant. These data suggested that L. rhamnosus YT and the cell-surface extract could be used as an alternative antimicrobial and antibiofilm agent against foodborne pathogens and spoilage bacteria in food industry.

Evaluation of the Antibacterial Effect of Xylene, Chloroform, Eucalyptol, and Orange Oil on Enterococcus faecalis in Nonsurgical Root Canal Retreatment: An Ex Vivo Study.

Objectives: The present ex vivo study is aimed at evaluating the antibacterial efficacy of chloroform, eucalyptol, orange oil, and xylene against E. faecalis biofilm during nonsurgical root canal retreatment. Materials and Methods: Eighty single-rooted teeth were instrumented. The samples were autoclaved, infected with E. faecalis for 4 weeks, and obturated with gutta-percha. Then the teeth were randomly assigned to 4 groups (n = 20): (1) chloroform, (2) eucalyptol, (3) orange oil, and (4) xylene. In all of the groups, gutta-percha removal was conducted according to the same protocol although the solvent used in each group was different. Bacterial samples were collected after gutta-percha removal and following additional apical enlargement. Intergroup and intragroup analyses were conducted using one-way ANOVA combined with the post hoc Tukey test and the paired-sample t-test, respectively. Statistical significance was set to 0.05. Results: All of the groups showed more than 99% bacterial load reduction. The least bacterial load after gutta-percha removal was observed in the chloroform group (p < 0.001). The orange oil group showed a significantly lower bacterial load compared to the eucalyptol group (p = 0.001), while it was not different from the xylene group (p = 0.953). The xylene group also had a significantly lower bacterial load compared with the eucalyptol group (p = 0.017). After apical enlargement, the chloroform group had a significantly lower bacterial load compared to the other groups. The comparison of bacterial load values before and after apical enlargement in the chloroform and eucalyptol groups showed a statistically significant difference (p choloroform = 0.011, p eucalyptol = 0.001). Conclusion: Chloroform was the most effective solvent in terms of antimicrobial activity against E. faecalis followed by orange oil and xylene, which were not significantly different though, and eucalyptol. All of the solvents showed more than 99% bacterial load reduction. Chloroform and xylene revealed to be associated with favorable antibiofilm activity among the examined solvents.

Heilaohuacid G, a new triterpenoid from Kadsura coccinea inhibits proliferation, induces apoptosis, and ameliorates inflammation in RA-FLS and RAW 264.7 cells via suppressing NF-𝜠B pathway.

Heilaohu, the roots of Kadsura coccinea, has been used in Tujia ethnomedicine to treat rheumatic arthritis (RA). Heilaohuacid G (1), a new 3,4-seco-lanostane type triterpenoid isolated from the ethanol extract of Heilaohu, whose structure was determined using HR-ESI-MS data, NMR spectroscopic analyses, and ECD calculations. In this study, our purpose is to elucidate the mechanisms of Heilaohuacid G in the treatment of RA by inhibited proliferation of rheumatoid arthritis-fibroblastoid synovial (RA-FLS) cells and inhibited the inflammatory reactions in LPS-induced RA-FLS and RAW 264.7 cell lines via inhibiting NF-κB pathway. The biological activity screening experiments indicated that Heilaohuacid G significantly inhibited proliferation of RA-FLS cells with IC50 value of 8.16 ± 0.47 µM. CCK-8 assay, ELISA, flow cytometry assay, and Western blot were used to measure the changes of cell viability, apoptosis, and the release of inflammatory cytokines. Heilaohuacid G was found not only induced RA-FLS cell apoptosis, but also inhibited the inflammatory reactions in LPS-induced RA-FLS and RAW 264.7 cell lines via inhibiting NF-κB pathway. Furthermore, Heilaohuacid G (p.o.) at doses of 3.0, 6.0, and 12.0 mg/kg and the ethanol extracts of Heilaohu (p.o.) at doses of 200, 400, and 800 mg/kg both were confirmed antiinflammatory effects on xylene-induced ear mice edema model.

Effects of replacing fish meal with cottonseed protein concentrate on the growth, immune responses, digestive ability and intestinal microbial flora in Litopenaeus vannamei.

The effects of cottonseed protein concentrate (CPC) in place of fishmeal on the growth performance, immune response, digestive ability and intestinal microbiota of Litopenaeus vannamei were investigated in this study. L. vannamei (initial body weight: 0.42 ± 0.01g) was fed for 8 weeks by four isonitrogenous and isolipid feeds with CPC replacing fishmeal (FM) at 0% (control), 15% (CPC15), 30% (CPC30) and 45% (CPC45), respectively. At the end of the study, the final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR) and protein efficiency ratio (PER) of L. vannamei in CPC15 and CPC30 groups were significantly increased, while the feed conversion ratio (FCR) of L. vannamei in the CPC30 group was significantly reduced when compared with the FM group (P < 0.05). After Vibrio parahaemolyticus infection, the cumulative mortality of L. vannamei in CPC15 within 24 hpi was significantly lower than that of the control group (P < 0.05). When compared with the control group, the activities and expression of the immunity-related enzymes in the hepatopancreas had almost the same obvious change trend in the CPC-containing groups, which indicated that the replacement for fishmeal by CPC led to significant immune response in L. vannamei. Besides, significant up-regulation of the digestive enzyme activities were observed in the CPC-containing groups. Analysis of intestinal microbiota showed that significant difference in alpha diversity existed between the CPC-containing groups and the control group. The relative abundances of several top 10 dominated species at the phylum and genus levels were significantly changed in the CPC-containing groups compared with the control group (P < 0.05). Functional prediction of the microbiota indicated that the pathway of protein digestion and absorption was significantly more abundant while the pathways of nitrotoluene degradation, aminobenzoate degradation, atrazine degradation, dioxin degradation and xylene degradation were significantly less abundant in the CPC-containing groups than the FM group (P < 0.05). In summary, optimal dietary CPC replacement of FM could improve the growth, immunity, digestive capacity and the diversities of the intestinal microbial flora of L. vannamei. However, parts of the functions of the intestinal microbial flora were decline.

Potential protective effect of puncturevine (Tribulus terrestris, L.) against xylene toxicity on bovine ovarian cell functions.

The action of the medicinal plant Tribulus terrestris (TT) on bovine ovarian cell functions, as well as the protective potential of TT against xylene (X) action, remain unknown. The aim of the present in vitro study was to elucidate the influence of TT, X and their combination on basic bovine ovarian cell functions. For this purpose, we examined the effect of TT (at doses of 0, 1, 10, and 100 ng/mL), X (at 20 ?g/mL) and the combination of TT + X (at these doses) on proliferation, apoptosis and hormone release by cultured bovine ovarian granulosa cells. Markers of proliferation (accumulation of PCNA), apoptosis (accumulation of Bax) and the release of hormones (progesterone, testosterone and insulin-like growth factor I, IGF-I) were analyzed by quantitative immunocytochemistry and RIA, respectively. TT addition was able to stimulate proliferation and testosterone release and inhibit apoptosis and progesterone output. The addition of X alone stimulated proliferation, apoptosis and IGF-I release and inhibited progesterone and testosterone release by ovarian cells. TT was able to modify X effects: it prevented the antiproliferative effect of X, induced the proapoptotic action of X, and promoted X action on progesterone but not testosterone or IGF-I release. Taken together, our observations represent the first demonstration that TT can be a promoter of ovarian cell functions (a stimulator of proliferation and a suppressor of apoptosis) and a regulator of ovarian steroidogenesis. X can increase ovarian cell proliferation and IGF-I release and inhibit ovarian steroidogenesis. These effects could explain its anti-reproductive and cancer actions. The ability of TT to modify X action on proliferation and apoptosis indicates that TT might be a natural protector against some ovarian cell disorders associated with X action on proliferation and apoptosis, but it can also promote its adverse effects on progesterone release.

Screening of subtype-specific activators and inhibitors for diacylglycerol kinase.

Diacylglycerol kinase (DGK) is a lipid kinase that converts diacylglycerol (DG) into phosphatidic acid (PA). DG and PA function as lipid messengers contributing to various signalling pathways. Thus, DGK plays a pivotal role in the signalling pathways by maintaining DG and PA levels. For example, DGKδ is involved in diabetes and DGKß is important for higher brain function including memory and emotion. Recently, we also revealed that the activation of DGKα ameliorated diabetic nephropathy (DN) in mice, suggesting that DGK can be therapeutic target. However, there is no commercially available DGK subtype-specific inhibitors or activators. Therefore, in a series of experiment to find DGK subtype-specific inhibitors or activators, we tried to screen novel DGKα activators from 9,600 randomly selected compounds by using high-throughput screening we had recently developed. Finally, we obtained two lead compounds for DGKα activators, KU-8 and KU-10. Focusing KU-8, we assessed the effect of KU-8 on all mammalian DGKs activities. Thus, KU-8 activates not only DGKα but also DGKθ by approximately 20%, and strongly inhibited DGKκ. In conclusion, KU-8 would be a good lead compound for DGKα and DGKθ activators, and useful as a DGKκ inhibitor.

Native musk and synthetic musk ketone strongly induced the growth repression and the apoptosis of cancer cells.

BACKGROUND: Musk is widely used in clinical practice for its anti-cancer properties. Here, we treated various types of cancer using musk to determine which cancers are sensitive to musk treatment. We also compared effects of native musk and synthetic musk ketone in cancer cells. Furthermore, we investigated mechanisms underlying effects of musk. METHODS: Twenty two cancer cell lines were treated with musk. Cell proliferation and apoptosis analyses were carried out. Native musk and synthetic musk ketone were analyzed by gas chromatograph-mass spectrometer (GC-MS) assay. Differentially expressed genes were determined by microarray and quantitative real-time polymerase chain reaction. RESULTS: Native musk strongly induced the growth repression and the apoptosis in the majority of cancer cell lines in a dose-dependent manner, but distinct types of cancer showed significantly different reactions. Cancer cells which originated from epithelial cells showed higher sensitivity for musk treatment. By contrast, leukaemia and lymphoma cells were not sensitive. GC-MS analysis demonstrated that native musk contains more than 30 contents in which musk ketone is a major component; synthetic musk ketone was consistent with natural musk ketone, and the used sample of synthetic musk ketone contained only sole component. Similar to native musk, synthetic musk ketone induced the growth repression and the apoptosis of cancer cells. Additionally, numerous genes were differentially expressed in lung cancer cells after native musk treatment. These differentially expressed genes were involved in many signalling pathways. Among these pathways, apoptosis-related pathways included interleukin family, tumor necrosis factor family, and MAPK signalling pathway. Native musk and synthetic musk ketone can up-regulate IL-24 (interleukin family) and DDIT3 (MAPK signalling pathway) in lung cancer cells. CONCLUSIONS: This research provided strong evidence that native musk and synthetic musk ketone can induce the growth repression and the apoptosis of cancer cells. However, the selection of sensitive cancer patient for individualized treatment is a key step in clinical application. Synthetic musk ketone can substitute for native musk to treat cancer patients. Musk might induce the growth repression and the apoptosis of lung cancer cells through up-regulating IL-24 and DDIT3 expressions.

Discovery of a new structural class of competitive hDHODH inhibitors with in vitro and in vivo anti-inflammatory, immunosuppressive effects.

Human dihydroorotate dehydrogenase (hDHODH) is an inner mitochondrial membrane enzyme that involves in the fourth step of the biosynthesis of pyrimidine base. Inhibitors of hDHODH have been proven efficacy for the treatments of inflammation, rheumatoid arthritis, multiple sclerosis and cancer. In the present study, ascochlorin (ASC) and its derivatives, natural compounds from fungal metabolites, were discovered as hDHODH inhibitors by high-throughput screening. Enzyme kinetics studies showed that ASC competitively binds to hDHODH at the site of coenzyme Q substrate. In ex vivo study, ASC significantly inhibited the ConA-stimulated T lymphocytes proliferation and interleukin-2, interferon-γ production. Furthermore, ASC showed significant in vivo anti-inflammatory and immunosuppressive effects on the mice ears swelling, allogenic skin grafts and rat collagen-induced arthritis animal disease models. ASC significantly reduced ears edema level of mice, increased the survival time of allogenic skin implanted on the mice and attenuated arthritis severity of rat model. In conclusion, ASC was identified as a new structural class of hDHODH inhibitors with efficient anti-inflammatory, immunosuppressive activity, and may be a promising candidate for the development of new therapy in the treatment of autoimmune diseases.

[Effects of musk ketone at different concentrations on in vivo migration of exogenous rat bone marrow mesenchymal stem cells].

OBJECTIVE: To study the effects of musk ketone at different concentrations on in vivo migration of exogenous rat bone marrow mesenchymal stem cells (rBMSCs), thus screening out the optimal therapeutic dose. METHODS: Forty SD rats were randomly divided into 4 groups, 10 in each group. The rat model of skull defect was established using dental surgery. The primary rBMSCs were cultured by adherence screening method. The third passage cells were labeled by 10 micromol/L BrdU, and the labeled cells were injected into skull defect rats from the tail vein. Rats were administered with musk ketone at high, moderate and low concentration, respectively by gastrogavage, while equal volume of normal saline was administered to those in the blank control group by gastrogavage. Their skulls were taken out 14 days later, fixed, and decalcified. BrdU positive cells were counted under fluorescence microscope. RESULTS: After immunohistochemical processing, the gray scale analysis was preformed. There was statistical difference in the BrdU positive cell number between the blank control group and the low and moderate concentration musk ketone groups (P < 0.01). There was no statistical difference in the BrdU positive cell number between the blank control group and the high concentration musk ketone group (P > 0.05). CONCLUSION: Musk ketone could accelerate the in vivo migration of exogenous stem cells, with the optimal effects obtained at moderate and low concentrations.

Antitumor and anti-invasive effects of diverse musk-fragrant macrocyclic ketones and their enhancement by hyperthermia.

The antitumor and anti-invasive activities of the low-molecular-weight macrocyclic ketones (MCKs), such as musk secreted from the mammalian genital glands and musk released from relatively unkown plants, were investigated comparatively together with the enhancement of the effects in combination with hyperthermia. Ehrlich ascites tumor cells were treated with each MCK and cultured, followed by evaluation of the cell viability using the mitochondrial dehydrogenase-based WST-8 assay. The number of HT-1080 human fibrosarcoma cells cultured with the MCKs or invading through a reconstituted basement membrane was measured using microscopy. The order of the efficiency was as follows: (Z)-g-cycloheptadecen-1-one (Hp) (17:1, musk rats), 8-cyclohexadecen-1-one (16:1, musk ferns), cyclopentadecanone (15:0, musk rats) and 3-methylcyclopentadecanone (16:0, musk deer), having 15-17 carbon atoms with and without a double bond, which exhibited a carcinostatic effect either at 100 µM for 20-h culture or at 50 µM for 72-h culture. The effects were markedly enhanced by heat treatment at 42˚C. MCKs were not found in the cells by gas-liquid chromatographic determination, indicating that the carcinostatic effects were attributed to their surface activity on the cell membrane. Invasion of HT-1080 cells was inhibited by MCKs at doses scarcely diminishing the cell viability, indicating that the suppression of invasiveness did not ensue from the secondary action due to carcinostasis. The order of invasion-inhibitory efficacy of the MCKs was, however, similar to that of their carcinostatic effects. Hp17:1 also exhibited the highest anti-invasive activity in addition to the highest carcinostatic activity. The two inhibitory effects were promoted by combination with hyperthermia. MCKs with a double bond, particularly Hp17:1 rather than 8-Hx16:1, but not saturated-aliphatic MCKs, may be potent multi-applicable antitumor agents due to their dual inhibitory activities against tumor progression and invasion and in hyperthermia-combined therapy.

Chemical composition, antinociceptive and anti-inflammatory properties of essential oil from the roots of Illicium lanceolatum.

Illicium lanceolatum is a popular aromatic and medicinal plant in China. Essential oil from the roots of I. lanceolatum, obtained by hydrodistillation, was analysed by GC-MS. The essential oil was dominated by phenylpropenes. The major components were myristicin (17.63%), α-asarone (17.23%), methyl isoeugenol (11.19%), apiol (8.82%) and isolongifolol (5.94%). When investigated using acetic acid-induced abdominal writhe models and the xylene-induced ear oedema model, the essential oil showed significantly antinociceptive and anti-inflammatory effects. The results indicate that the essential oil may contain the bioactive components of I. lanceolatum. This is the first report on the chemistry, antinociceptive and anti-inflammatory activities of I. lanceolatum.

In vitro reactivation of sarin-inhibited human acetylcholinesterase (AChE) by bis-pyridinium oximes connected by xylene linkers.

A series of bis-pyridinium oximes connected by xylene linkers were synthesized and their in vitro reactivation potential was evaluated against human acetylcholinesterase (hAChE) inhibited by nerve agent sarin and the data were compared with 2-PAM and obidoxime. Among the synthesized compounds, N,N'-p-xylene-bis-[(2,2'-hydroxyiminomethyl)pyridinium] dibromide (3c) was found to be the most potent reactivator for hAChE inhibited by sarin. The oxime 3c exhibited 45% regeneration of inhibited hAChE, in comparison to 34% and 24% regeneration by 2-PAM and obidoxime, respectively, at a concentration of 10(-3) M within 10 min. The higher reactivation efficacies of these oximes were attributed to their acid dissociation constants (pKa). The pKa values of all the oximes were determined spectrophotometrically and correlated with their observed reactivation potential. This method involving the in vitro reactivation of inhibited hAChE may be useful for the screening of new oximes as reactivators.

The antiviral action of common household disinfectants and antiseptics against murine hepatitis virus, a potential surrogate for SARS coronavirus.

BACKGROUND: The 2003 outbreak of severe acute respiratory syndrome (SARS) infected over 8000 people and killed 774. Transmission of SARS occurred through direct and indirect contact and large droplet nuclei. The World Health Organization recommended the use of household disinfectants, which have not been previously tested against SARS coronavirus (SARS-CoV), to disinfect potentially contaminated environmental surfaces. There is a need for a surrogate test system given the limited availability of the SARS-CoV for testing and biosafety requirements necessary to safely handle it. In this study, the antiviral activity of standard household products was assayed against murine hepatitis virus (MHV), as a potential surrogate for SARS-CoV. METHODS: A surface test method, which involves drying an amount of virus on a surface and then applying the product for a specific contact time, was used to determine the virucidal activity. The virus titers and log reductions were determined by the Reed and Muench tissue culture infective dose (TCID)50 end point method. RESULTS: When tested as directed, common household disinfectants or antiseptics, containing either 0.050% of triclosan, 0.12% of PCMX, 0.21% of sodium hypochlorite, 0.23% of pine oil, or 0.10% of a quaternary compound with 79% of ethanol, demonstrated a 3-log reduction or better against MHV without any virus recovered in a 30-second contact time. CONCLUSION: Common household disinfectants and antiseptics were effective at inactivating MHV, a possible surrogate for SARS-CoV, from surfaces when used as directed. In an outbreak caused by novel agents, it is important to know the effectiveness of disinfectants and antiseptics to prevent or reduce the possibility of human-to-human transmission via surfaces.

Anti-inflammatory components isolated from Atractylodes macrocephala Koidz.

The petroleum ether-ether (1 : 1) extract of Atractylodis macrocephalae was screened by cell membrane chromatography (CMC) and subsequently separated by column chromatography (CC) and high performance liquid chromatography (HPLC). Five components were isolated and identified as atractylenolide III 1, atractylenolide I 2, 14-acetoxy-12-senecioyloxytetradeca-2E,8E,10E-trien-4,6-diyn-1-ol 3, 14-acetoxy-12-alpha-methylbutyl-2E,8E,10E-trien-4,6-diyn-1-ol 4 and 14-acetoxy-12-beta-methylbutyl-2E,8E,10E-trien-4,6-diyn-1-ol 5 by routine spectrometric methods. The data of 5 and (13)C-NMR data of 3 and 4 were reported for the first time. Further in vivo experiments showed that the five components exhibited significant inhibiting effects both on the ear edema induced by xylene and on the peritoneal capillary permeability induced by acetic acid in mice.

S5 Lipase: an organic solvent tolerant enzyme.

In this study, an organic solvent tolerant bacterial strain was isolated. This strain was identified as Pseudomonas sp. strain S5, and was shown to degrade BTEX (Benzene, Toluene, Ethyl-Benzene, and Xylene). Strain S5 generates an organic solvent-tolerant lipase in the late logarithmic phase of growth. Maximum lipase production was exhibited when peptone was utilized as the sole nitrogen source. Addition of any of the selected carbon sources to the medium resulted in a significant reduction of enzyme production. Lower lipase generation was noted when an inorganic nitrogen source was used as the sole nitrogen source. This bacterium hydrolyzed all tested triglycerides and the highest levels of production were observed when olive oil was used as a natural triglyceride. Basal medium containing Tween 60 enhanced lipase production to the most significant degree. The absence of magnesium ions (Mg2+) in the basal medium was also shown to stimulate lipase production. Meanwhile, an alkaline earth metal ion, Na+, was found to stimulate the production of S5 lipase.

Investigation of antibiotic and antibacterial agent cross-resistance in target bacteria from homes of antibacterial product users and nonusers.

AIM: To describe the relationship between antibiotic and antibacterial resistance in environmental and clinical bacteria from home environments across geographical locations, relative to the use or nonuse of antibacterial products, with a focus on target organisms recognized as potential human pathogens. METHODS AND RESULTS: In a randomized study, environmental and clinical samples were collected from the homes of antibacterial product users (n=30) and nonusers (n=30) for the isolation of target bacteria for antibiotic and antibacterial testing in three geographical areas (in USA and UK). Isolates were tested for antibiotic susceptibility, with selected antibiotic-resistant and antibiotic-susceptible isolates tested against four common antibacterial agents (triclosan, para-chloro-meta-xylenol, pine oil and quaternary ammonium compound). Prequalified users and nonusers at each location were randomly selected after meeting exclusionary criteria. Of 1238 isolates, more target bacteria were recovered from nonuser than user homes. Of Staphylococcus aureus isolates (n=33), none showed resistance to oxacillin or vancomycin; for Enterococcus sp. (n=149), none were resistant to ampicillin or vancomycin; and for Klebsiella pneumoniae (n=54)and Escherichia coli (n=24), none were resistant to third generation cephalosporins. Antibiotic resistance to one or more of the standard test panel drugs for Gram-positive and Gram-negative target bacteria was comparable between nonuser and user homes for both environmental and clinical isolates [e.g. resistance of environmental coagulase-negative (CN) Staphylococcus sp. was 73.8% (124/168) from nonuser homes and 73.0% (111/152) from user homes, and Enterobacteriaceae other than E. coli, 75.9% (186/245) from nonuser homes compared with 78.0% from user homes]. Of 524 Gram-negatives tested against preferred/alternative drugs, 97.1% (509/524) were susceptible to all antibiotics, across both groups. Isolates of S. aureus, Enterococcus sp. and CN Staphylococcus sp. susceptible to all preferred treatment drugs showed comparable antibacterial minimum inhibitory concentration (MIC) results between nonuser and user home isolates. For Gram-positives resistant to one or more preferred drugs, greatest resistance to antibacterial active ingredients was found in the nonuser group. For Gram-negatives, the antibacterial MIC data were comparable for isolates that were fully susceptible and resistant to one or more preferred/alternative treatment antibiotics. CONCLUSIONS: The results showed a lack of antibiotic and antibacterial agent cross-resistance in target bacteria from the homes of antibacterial product users and nonusers, as well as increased prevalence of potential pathogens in nonuser homes. SIGNIFICANCE AND IMPACT OF THE STUDY: It refutes widely publicized, yet unsupported, hypotheses that use of antibacterial products facilitates the development of antibiotic resistance in bacteria from the home environment.

Antinociceptive, anti-inflammatory and acute toxicity effects of Zhumeria majdae extracts in mice and rats.

Antinociceptive and anti-inflammatory effects and acute toxicity of aqueous infusion and ethanolic maceration extracts of the aerial parts of Zhumeria majdae were studied in mice and rats. Antinociceptive activity was determined using hot-plate and writhing tests. The effect of the extracts against acute inflammation was studied by acetic acid increased vascular permeability and xylene-induced ear edema in mice. The activity of the extracts against chronic inflammation was assessed using the cotton pellet test in rats. LD50 values of the infusion and maceration extracts were 3.09 g/kg body wt., and 3.94 g/kg body wt., respectively. Phytochemical screening of the extracts indicated the presence of flavonoids and tannins. In the hot-plate test, the intraperitoneal injection of both extracts showed significant and dose-dependent antinociceptive activity in mice. Naloxone, an opioid antagonist, on pretreatment inhibited the antinociceptive activity of the extracts. The extracts exhibited antinociceptive activity against acetic acid-induced writhing, which was partially blocked by naloxone. Both extracts showed significant effect against acute inflammation induced by acetic acid in mice. In the chronic inflammation test, efficacy of the extracts was similar to that of baclofen and dexamethasone in rats. It is concluded that the aqueous infusion and ethanolic maceration extract of the aerial parts of Zhumeria majdae have antinociceptive effects and this may be mediated by opioid receptors. The extracts also showed anti-inflammatory effects against acute and chronic inflammation.

Antimicrobial efficacy of chloroxylenol and chlorhexidine in the treatment of infected root canals.

PURPOSE: To investigate the antimicrobial efficacy of a chlorhexidine gluconate (2.0%) and of an ethanolic chloroxylenol solution (10%) as a temporary root canal dressing against selected test microorganisms (Staphylococcus aureus, Streptococcus faecium, Escherichia coli, Candida albicans). MATERIALS AND METHODS: Extracted single-rooted human teeth were instrumented up to size 40. After removal of the smear layer suspensions of the test microorganisms were inserted into the root canals. After incubation for 48 hrs each suspension of the test organisms was removed and the root canals were filled with one of the two different disinfectants. The teeth were then incubated for 48 hrs. Twelve teeth and three controls were used for each of the four test organisms and each of the two regimens. After incubation, each root canal was instrumented and the removed canal wall dentin was examined microbiologically. RESULTS: With a contact time of 48 hrs between the two disinfectants and the four bacterial suspensions the medications led to a total killing of microorganisms in 82% of a total of 96 contaminated teeth. In the dentin layer situated 50 microm from the root canal, both medications achieved bacterial killing in a range from 99.9% to 99.99%, depending on the test organism. There were no significant differences (P> 0.1) between the relative antimicrobial activity of the two root canal dressings.