A Study on THE Mechanism of Electroacupuncture to Alleviate Visceral Pain and NGF Expression.

Visceral pain is unbearable, and natural methods are needed to relieve it. Electroacupuncture is a relatively new technique that helps relieve visceral pain by improving blood circulation and providing energy to clogged parts of the body. However, its analgesic effect and mechanism in colorectal pain are still unknown. In this study, the visceral pain models of electroacupuncture in rats were compared and discussed, using nanocomponents to stimulate the expression and mechanism of the nerve growth factor in colorectal pain and electroacupuncture and to observe the expression and mechanism of nerve growth factor in visceral pain relief rats induced by nanocomponents and electroacupuncture. The results show that nanocomponents can effectively relieve visceral pain under the action of electroacupuncture. NGF can activate endogenous proliferation, migration, differentiation, and integration. NSC can promote nerve regeneration and recovery after injury.

The Effect of Transcutaneous Electrical Acupoint Stimulation on Postoperative Catheter-Related Bladder Discomfort in Patients Undergoing Transurethral Resection of the Prostate.

BACKGROUND: Catheter-related bladder discomfort (CRBD), an extremely distressing complication secondary to an indwelling urinary catheterization, is frequently reported in patients with transurethral resection of the prostate (TURP), postoperatively. A prospective, randomized, controlled, double-blind study was designed to assess the efficacy of transcutaneous electrical acupoint stimulation (TEAS) as a treatment for CRBD in patients undergoing TURP. METHODS: Seventy benign prostatic hyperplasia male patients undergoing TURP under general anesthesia requiring intraoperative urinary catheterization were enrolled for the trial. An experienced acupuncturist performed TEAS for 30 minutes before general anesthesia with acupoints RN7, RN6, RN5, RN4, and RN3 and bilateral BL32, BL33, and BL34. Mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SPO2), body temperature (T), and blood samples were collected during the surgery. A series of assessments included the incidence and severity of CRBD, postoperative pain, nausea and vomiting, and physical and mental state measurements. RESULTS: The incidence of CRBD was significantly lower in TEAS group than in control group at the time T5 [9(26%) vs. 28(80%), P < 0.001], T9 [20(57%) vs. 28(80%), P=0.039], T11 [7(20%) vs. 31(89%), P < 0.001], and T12 [4(11%) vs. 7(20%), P=0.003]. The severity of CRBD was significantly lower in TEAS group than in control group at the time T5 [0 vs. 10 (29%), P < 0.001], T9 [2(6%) vs. 10(29%), P=0.011], and T11 [0 vs .9(26%), P=0.002]. The QoR-40 total score was higher in TEAS group at time T11 [191.7(4.4) vs. 189.1(4.3), P=0.007] and T12 [195.3(1.9) vs. 193.3(3.0), P < 0.001]. The postoperative analgesia requirement was higher in control group [5.0(2.9) vs. 3.8(1.9), P=0.045]. CONCLUSIONS: TEAS could significantly prevent the incidence and severity of CRBD, reduce the postoperative analgesic requirement in the early postoperative period, and promote the quality of early recovery in patients undergoing TURP.

Comparison of triadimefon and its metabolite on acute toxicity and chronic effects during the early development of Rana nigromaculata tadpoles.

Pesticides are one of major causes for amphibian population declines and the behavior of pesticide metabolite products to amphibians has become a rising concern. In this study, the acute toxicity and the chronic effects of triadimefon and triadimenol (the metabolite of triadimefon) on Rana. nigromaculata were investigated. In the acute assay, significant differences were observed in antioxidant enzyme activities and malondialdehyde levels between the triadimefon and triadimenol. The 96 h-acute toxicity of triadimefon (25.97 mg/L) and triadimenol (34.55 mg/L) to tadpoles was low. In 28d-chronic exposure, we studied the relative expression of tadpoles genes related to thyroid hormone-dependent metamorphic development, histological examination of liver and some biological index, including wet weight, snout-to-vent length (SVL) and development stages. The results revealed that the effects of triadimefon and triadimenol on tadpole development are driven by a disruption of the hormonal pathways involved in metamorphosis. Interestingly, triadimefon was more harmful on R. nigromaculata than triadimenol at high dose, whereas the reverse result was observed at low doses. According to the relative expression of thyroid hormone-dependent genes, we also found that the two compounds may have different mechanisms of toxic action on R. nigromaculata. Our study developed a pragmatic approach for use in the risk assessment of pesticide and its metabolite，and increased the information and understanding of the impacts of fungicides and other potential endocrine disrupting environmental contaminants on amphibians.

The Effect of Transcutaneous Electrical Acupoint Stimulation on Inflammatory Response in Patients Undergoing Limb Ischemia-Reperfusion.

Reperfusion after tourniquet use can induce inflammation and cause remote organ injury. We evaluated the therapeutic effect of transcutaneous electrical acupoint stimulation (TEAS) on inflammatory mediators and lung function in patients receiving lower limb tourniquets. Forty patients undergoing unilateral lower extremity surgery with tourniquet were randomly assigned to two groups: the TEAS group and ischemia-reperfusion (I/R) group. The C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine ligand 8 (CXCL8), interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and arterial blood gas analysis were measured preoperatively and 6 h after tourniquet removal. The levels of CXCL8, IL-1, IL-6, TNF-α, and CCL2 were significantly increased compared to baseline values in both groups, but the increase was significantly smaller in the TEAS group. In the TEAS group, the partial pressure of oxygen and arterial-alveolar oxygen tension ratio were significantly decreased, and the alveolar-arterial oxygen tension difference and respiratory index were significantly increased, compared to those in the I/R group at 6 h after reperfusion. In conclusion, TEAS diminished the upregulation of proinflammatory factors in response to lower limb ischemia-reperfusion and improved pulmonary gas exchange.

Effects of α-cypermethrin enantiomers on the growth, biochemical parameters and bioaccumulation in Rana nigromaculata tadpoles of the anuran amphibians.

Populations of many amphibian species are declining worldwide in part because of pesticide contamination. As a surface water contaminant, α-cypermethrin may have severe ecological impacts on amphibians. Here, we examined the acute toxicity of α-cypermethrin enantiomers to dark-spotted frog Rana nigromaculata tadpoles at 24, 48, 72 and 96h, finding that the tadpoles were indeed sensitive to α-cypermethrin. The (S)-(1R, 3R)-enantiomer was approximately 29 times more toxic than the (R)-(1S, 3S)-enantiomer at 96h. A significant delayed growth in R. nigromaculata tadpoles after exposure to 0.5µgL-1 of S-(1R, 3R)-cypermethrin was observed. Additionally, increased superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST) and malondialdehyde (MDA) levels indicate the presence of oxidative stress in the tadpoles. Further, tadpoles exposed to sublethal concentrations of α-cypermethrin enantiomers exhibited enantioselective growth and oxidative damage. Bioaccumulation experiments showed that the tadpoles could rapidly accumulate α-cypermethrin. The (R)-(1S, 3S)-enantiomer was preferentially accumulated over the (S)-(1R, 3R)-enantiomer, and it was also eliminated more quickly, as evidenced in the subsequent depuration experiments.

Stereoselective bioaccumulation, transformation, and toxicity of triadimefon in Scenedesmus obliquus.

In this study the stereoselective bioaccumulation and transformation of triadimefon and the toxicity of triadimefon and its metabolite triadimenol to the green algae Scenedesmus obliquus were studied. In growth inhibition experiments, triadimenol was more toxic than triadimefon, and (1S,2R)-triadimenol, which has the largest fungicidal activity, presented the highest toxicity to the algae. In bioaccumulation experiments, triadimefon was rapidly taken up by algae cells, and the decrease in the concentration of triadimefon was accompanied by an increase in triadimenol. The transformation of S-(+)- triadimefon was faster than that of the R-(-)-enantiomer, resulting in four triadimenol stereoisomers at different forming rates: B2 (1S, 2S) > B1 (1R, 2R) > A2 (1S, 2R) > A1 (1R, 2S). Thus, it is necessary to explore the enantioselective toxicology and ecological fate of these chiral pesticides in an environmental risk assessment. Also, their metabolites should be paid specific attention to since they may pose higher ecological risks.

Selective bioaccumulation and elimination of hexachlorocyclohexane isomers in Tubifex tubifex (Oligochaeta, Tubificidae).

In this study, Tubifex tubifex worms were exposed to sediment-associated hexachlorocyclohexane (HCH) isomers to study the bioaccumulation and elimination behaviors of HCH isomers in T. tubifex. During a 10-day bioaccumulation experiment, bioaccumulation curves of HCHs were approximate to M-type in T. tubifex. The enantioselective behaviors of α-HCH enantiomers were observed in T. tubifex, with concentrations of (+)-α-HCH higher than that of (-)-α-HCH. The concentration of γ-HCH in T. tubifex was higher than that of ß-HCH and α-HCH. The existence of worms can accelerate the dissipation of HCHs in sediment, and the dissipation half-lives of α-HCH, ß-HCH, and γ-HCH were 8.39, 23.90, and 3.10 days, respectively. In the elimination experiment, approximately 0.053 (37.1%), 0.074 (45.9%), and 0.042 mg/kgwwt (38.4%) α-HCH, ß-HCH, and γ-HCH were depleted or excreted in T. tubifex on the first day, respectively. The body residues in T. tubifex were 0.084 (α-HCH), 0.082 (ß-HCH), and 0.061 mg/kgwwt (γ-HCH) at the end of elimination experiment. Furthermore, the existence of T. tubifex could affect the overlying water quality parameters.

Enantioselective toxicity and degradation of the chiral insecticide fipronil in Scenedesmus obliguus suspension system.

Fipronil is an effective insecticide, but it presents highly toxic effects in nontarget aquatic organisms. The present study examined the enantioselective toxicity and degradation of fipronil enantiomers in a freshwater algae Scenedesmus obliguus suspension. There was a substantial difference in the acute toxicity of the enantiomers to S. obliguus, with 72-h median effective concentrations (EC50s) of 0.29 mg L(-1) and 1.50 mg L(-1) for the R-fipronil and S-fipronil, respectively. The influences on the concentration of chlorophyll a, chlorophyll b, and carotenoids were determined, and the effects of fipronil on the concentration of chlorophyll a and chlorophyll b were also enantioselective. The degradation of fipronil in algae suspension was enantioselective, with half-lives for R-fipronil and S-fipronil of 2.9 d and 3.2 d, respectively, and the enantiomer fraction reaching 0.65 at the day 17. The enantiomeric differences should be taken into consideration for fipronil risk assessment.

Enantioselective toxic effects and degradation of myclobutanil enantiomers in Scenedesmus obliquus.

Research on the enantioselective environmental behavior of chiral pesticides has been a hot spot of environmental chemistry recently. In this study, the acute toxicity of myclobutanil enantiomers was investigated with the aquatic algae Scendesmus obliquus. After exposure for 96 h, the EC50 values for (-)-myclobutanil, rac-myclobutanil and (+)-myclobutanil were 3.951, 2.760, and 2.128 mg/L, respectively. The photosynthetic pigment (chlorophyll a, chlorophyll b, and carotenoids) and antioxidant enzyme activities catalase (CAT) were determined to evaluate the different toxic effects when S. obliquus were exposed to 1.5, 5 and 15 mg/L of rac-myclobutanil, (-)-myclobutanil, and (+)-myclobutanil for 96 h, respectively. In addition, the degradation of myclobutanil enantiomers in S. obliquus was also studied. Myclobutanil in the medium inoculated with algae degraded faster than in the uninoculated medium. The degradation of (-)-myclobutanil was faster than that of (+)-myclobutanil at a concentration of 3 mg/L. On the basis of these data, the acute toxicity and toxic effects of myclobutanil against S. obliquus were concluded to be enantioselective, and such enantiomeric differences should be taken into consideration in pesticide risk assessment.

Enantioselective toxic effects of hexaconazole enantiomers against Scenedesmus obliquus.

Enantioselectivity in ecotoxicity of chiral pesticides in the aquatic environment has been a subject of growing interest. In this study, the toxicological impacts of hexaconazole enantiomers were investigated with freshwater algae Scenedesmus obliquus. After 96 h of exposure, the EC(50) values for rac-hexaconazole, (+)-hexaconazole, and (-)-hexaconazole were 0.178, 0.355, and 0.065 mg l(-1) , respectively. Therefore, the acute toxicities of hexaconazole enantiomers were enantioselective. In addition, the different toxic effects were evaluated when S. obliquus were exposed to 0.2, 0.5, and 1.0 mg l(-1) of rac-hexaconazole, (+)-hexaconazole, and (-)-hexaconazole during 96 h, respectively. The chlorophyll a and chlorophyll b contents of S. obliquus treated by (-)-hexaconazole were lower than those exposed to (+)-hexaconazole, whereas the malondialdehyde contents of S. obliquus treated by (-)-form were higher than those exposed to (+)-form at higher concentrations. In general, catalase activities were significantly upregulated by exposure to (-)-enantiomer than (+)-enantiomer at all three concentrations. However, superoxide dismutase activities exposed to (-)-hexaconazole were lower than that exposed to (+)-hexaconazole at 0.2 mg l(-1) and 0.5 mg l(-1) . On the basis of these data, the acute toxicity and toxic effects of hexaconazole against S. obliquus were enantioselective, and such enantiomeric differences must be taken into consideration in pesticide risk assessment.

Enantioselective toxicological response of the green alga Scenedesmus obliquus to isocarbophos.

Chiral compounds usually behave enantioselectively in phyto-biochemical processes. Isocarbophos (ICP) is a chiral pesticide that is widely used. To evaluate the toxicological response of ICP and its enantiomers to Scenedesmus obliquus, algal growth, total chlorophyll, total soluble protein, and the superoxide anion radicals (O(2)(•-)) were investigated. The microalgae were treated with ICP and its enantiomers at 0.01-10 mg/l for 96 h. The growth of S. obliquus was stimulated at low levels of ICP and its enantiomers (0.01-1 mg/l), but all were inhibited at high concentrations (10 mg/l). The total soluble protein content and total chlorophyll content of the tested green alga S. obliquus gradually increased, depending on the growth of algal cells in the medium. Meanwhile, the content of O(2)(•-) was decreased. Interestingly, the cell number and content of the chlorophylls and protein decreased with increasing levels of concentration, whereas O(2)(•-) increased. Our results indicated that enantioselectivity was observed in the dose-response of ICP and its enantiomers in S. obliquus. The high O(2)(•-) level might lead to the death of S. obliquus. The stimulation of growth suggests a regulatory mechanism that is related to the capability of the algae to adapt to the O(2)(•-).

Enantioselective toxic effects and biodegradation of benalaxyl in Scenedesmus obliquus.

Enantioselectivity in ecotoxicity and biodegradation of chiral pesticide benalaxyl to freshwater algae Scenedesmus obliquus was studied. The 96 h-EC(50) values of rac-, R-(-)-, S-(+)-benalaxyl were 2.893, 3.867, and 8.441 mg L(-1), respectively. Therefore, the acute toxicities of benalaxyl enantiomers were enantioselective. In addition, the pigments chlorophyll a and chlorophyll b, antioxidant enzyme activities catalase (CAT) and superoxide dismutase (SOD) as well as lipid peroxide malondialdehyde (MDA) were determined to evaluate the different toxic effects. Chlorophyll a was induced by S-(+)-benalaxyl but inhibited by R-(-)-benalaxyl at 1 mg L(-1). Chlorophyll b were both induced at 1 mg L(-1), but S-(+)-form was fourfold higher than R-(-)-form. S-(+)-benalaxyl inhibited more CAT activities at 3 mg L(-1) and 5 mg L(-1), induced less SOD activity and MDA content at 5 mg L(-1) than R-(-)-benalaxyl. Based on these data, enantioselectivity occurred in anti-oxidative stress when S. obliquus response to benalaxyl. In the biodegradation experiment, the half-lives of S-(+)-benalaxyl and R-(-)-benalaxyl were 4.07 d and 5.04 d, respectively, resulting in relative enrichment of the R-(-)-form. These results showed that toxic effects and biodegradation of benalaxyl in S. obliquus were enantioselective, and such enantiomeric differences must be taken into consideration in pesticide risk.

Stereoselective metabolism of benalaxyl in liver microsomes from rat and rabbit.

Benalaxyl (BX), methyl-N-phenylacetyl-N-2,6-xylyl alaninate, is a potent acylanilide fungicide and consist of a pair of enantiomers. The stereoselective metabolism of BX was investigated in rat and rabbit microsomes in vitro. The degradation kinetics and the enantiomer fraction (EF) were determined using normal high-performance liquid chromatography with diode array detection and a cellulose-tris-(3,5-dimethylphenylcarbamate)-based chiral stationary phase (CDMPC-CSP). The t(1/2) of (-)-R-BX and (+)-S-BX in rat liver microsomes were 22.35 and 10.66 min of rac-BX and 5.42 and 4.03 of BX enantiomers. However, the t(1/2) of (-)-R-BX and (+)-S-BX in rabbit liver microsomes were 11.75 and 15.26 min of rac-BX and 5.66 and 9.63 of BX enantiomers. The consequence was consistent with the stereoselective toxicokinetics of BX in vitro. There was no chiral inversion from the (-)-R-BX to (+)-S-BX or inversion from (+)-S-BX to (-)-R-BX in both rabbit and rat microsomes. These results suggested metabolism of BX enantiomers was stereoselective in rat and rabbit liver microsomes.