Objective To evaluate the molluscicidal effect of niclosamide ethanolamine salt powder?granula(PG)against Oncomelania hupensis. Methods The molluscicidal experiment was carried out by the dusting method with niclosamide etha?nolamine salt 4%PG. The experiments were respectively done in the laboratory and the tidal flats wetlands. At the same time , the niclosamide ethanolamine salt 4%dustable powder(DP)was as the control group. The single blind method was used for the quality control. The corrected mortality and the median lethal concentration(LC50)were compared between PG and DP in the molluscicidal experiment of the laboratory. The corrected mortality and the reduced rate of snails’density were compared be?tween PG and DP in the tidal flats wetlands. Results The mortality rates of the snails were 96.67%and 100%respectively on 1 d after dusting 4.0 g/m2 of 4% PG and 2.0 g/m2 of 4% DP in the laboratory. The results showed that the mortality rates of the snails were higher with 4%DP than 4%PG in each dosage(t1 d=3.60,P<0.01). The LC50(s) of 1d,3 d,7 d after dusting the molluscicide also showed that the molluscicidal effects of DP were better than PG. The corrected mortality rates were 91.71%, 92.91%,90.57%,85.33%and 71.09%,90.11%,90.13%,85.26%on 3 d,7 d,15 d,30 d after dusting with 4%PG and 4%DP,respectively,in the fields. Statistics showed that the mortality rates of snails were higher on 3 d,7 d after dusting with PG than DP(c23 d=731.57,c27 d=25.90,P<0.01),but there were no significant differences between PG and DP on 15d,30d af?ter dusting(c215 d=0.53,c230 d=0.01,P>0.05). Conclusions 4%PG has both the adsorption of powder and the penetrability of the granules. The molluscicidal effects of 4%PG and 4%DP are almost the same. However,the drift of the powder was still not effectively controlled. This problem need to be further studied.

The effects of phorbol-12,13-dibuterate (PDBu) on total sodium current (INa-total), tetrodotoxin-resistant sodium current (INa-TTXr), 4-AP-sensitive potassium current (IA) and TEA-sensitive potassium current (IK) in trigeminal ganglion (TG) neurons were investigated.Whole-cell patch clamp techniques were used to record ion currents in cultured TG neurons of rats. Results revealed that 0.5 μmol/L PDBu reduced the amplitude of INa-total by (38.3±4.5)% (n=6, P＜0.05), but neither the G-V curve (control: V0.5 =-17.1±4.3 mV, k=7.4±1.3; PDBu: V0.5=-15.9±5.9 mV, k=5.9±1.4; n=6, P＞0.05) nor the inactivation rate constant (control: 3.6±0.9 ms; PDBu: 3.6±0.8 ms; n=6, P＞0.05) was altered. 0.5 μmol/L PDBu could significantly increase the amplitude of INa-TTXr by (37.2± 3.2)% (n=9, P＜0.05) without affecting the G-V curve (control: V0.5=-14.7±6.0 mV, k=6.9±1.4; PDBu: V0.5=-11.1±±5.3 mV, k=8.1±1.5; n=5, P＞0.05) or the inactivation rate constant (control: 4.6±±0.6 ms; PDBu: 4.2±0.5 ms; n=5, P＞0.05). 0.5 μmol/L PDBu inhibited IK by (15.6±5.0) % (n=16, P＜0.05), and V0.5 was significantly altered from - 4.7±1.4 mV to -7.9 ±1.8 mV (n=16, P＜0.05). IA was not significantly affected by PDBu, 0.5 μmol/L PDBu decreased IA by only (0.3±3.2)% (n=5, P＞0.05). It was concluded that PDBu inhibited INa-total but enhanced INa-TTXr, and inhibited IK without affecting IA. These data suggested that the activation of PKC pathway could exert the actions.

The effects of phorbol-12,13-dibuterate (PDBu) on total sodium current (I(Na)-total), tetrodotoxin-resistant sodium current (I(Na)-TTXr), 4-AP-sensitive potassium current (I(A)) and TEA-sensitive potassium current (I(K)) in trigeminal ganglion (TG) neurons were investigated. Whole-cell patch clamp techniques were used to record ion currents in cultured TG neurons of rats. Results revealed that 0.5 micromol/L PDBu reduced the amplitude of I(Na)-total by (38.3+/-4.5)% (n=6, P<0.05), but neither the G-V curve (control: V (0.5)=-17.1+/-4.3 mV, k=7.4+/-1.3; PDBu: V (0.5)=-15.9+/-5.9 mV, k=5.9+/-1.4; n=6, P>0.05) nor the inactivation rate constant (control: 3.6+/-0.9 ms; PDBu: 3.6+/-0.8 ms; n=6, P>0.05) was altered. 0.5 micromol/L PDBu could significantly increase the amplitude of I(Na)-TTXr by (37.2+/-3.2)% (n=9, P<0.05) without affecting the G-V curve (control: V (0.5)=-14.7+/-6.0 mV, k=6.9+/- 1.4; PDBu: V (0.5)=-11.1+/-5.3 mV, k=8.1+/-1.5; n=5, P>0.05) or the inactivation rate constant (control: 4.6+/-0.6 ms; PDBu: 4.2+/-0.5 ms; n=5, P>0.05). 0.5 mumol/L PDBu inhibited I(K) by (15.6+/-5.0) % (n=16, P<0.05), and V (0.5) was significantly altered from - 4.7+/-1.4 mV to -7.9 +/-1.8 mV (n=16, P<0.05). I(A) was not significantly affected by PDBu, 0.5 mumol/L PDBu decreased I(A) by only (0.3+/-3.2)% (n=5, P>0.05). It was concluded that PDBu inhibited I(Na)-total but enhanced I(Na)-TTXr, and inhibited I(K) without affecting I(A). These data suggested that the activation of PKC pathway could exert the actions.

To further investigate the mechanisms of action of icariin (ICA), we assessed the effects of ICA on the in vitro formation of cGMP and cAMP in isolated rabbit corpus cavernosum. Isolated segments of rabbit corpus cavernosum were exposed to increasing concentrations of ICA and the dose-dependent accumulation of cGMP and cAMP was determined in the tissues samples by means of 125I radioimmunoassay. Responses of the isolated tissues preparations to ICA were compared with those obtained with the reference compounds sildenafil (Sild). Furthermore, the effects of ICA on the mRNA expression of specific cGMP-binding phosphodiesterase type V (PDE5) in rat penis were also observed. After incubation with ICA for 6 h or 14 h respectively, the levels of PDE5 mRNA were examined by reverse transcriptase polymerase chain reaction (RT-PCR). The results showed that ICA increased cGMP concentrations directly (P＜0.05), but there was no significant effect on cAMP concentrations (P＞0.05). In the presence of sodium nitroprusside (SNP), a stimulatory agent of cGMP,both ICA and Sild increased cGMP concentrations with increasing dose (P＜0.01). Their EC50 was 4.62 (ICA) and 0.42 (Sild) μmol/L respectively. Under the same condition, ICA and Sild unaltered cAMP level significantly (P＞0.05). There were PDE5A1 and PDE5A2 mRNA expressions in rat corpus cavernosum with PDE5A2 being the dominant isoform. ICA could obviously inhibit these two isoforms mRNA expression in rat penis, and decrease PDE5A1 more pronouncedly (P＜ 0.01). The present study indicated that the aphrodisiac mechanisms of icariin involved the NO-cGMP signal transduction pathway, with increasing cGMP levels in the corpus cavernosum smooth muscle. The inhibitory effect of icariin on PDE5 mRNA expression, especially on PDE5A1, might account for its molecular mechanisms for its long-term activity.

Objective To develop a selective isolation media which has a high isolation ratio for Legionella.Methods We compared the growth of Legionella pneumonia on BCYE? plate (with DGVP), BCYE?(with GVPC) and BCYE? (with CCCV) by colony count and compared with BCYE? plate. The comparison of isolation ratio of Legionella pneumonia from air-conditions cooling water with 3 kinds of BCYE? plate containing different anti-reagents was performed.Results The results of colony count on BCYE? plate (with DGVP) and BCYE?(with GVPC) was identical with that on BCYE? plate at same concentration. But the result of colony count on BCYE? plate (with CCCV) was half of the former 2 kinds of plate. 5 strains of Legionella pneumonia isolated from 9 central air-condition cooling water were used by BCYE? plate (with DGVP) and BCYE? (with GVPC), while only 2 strains of Legionella pneumonia were isolated by BCYE? plate (with CCCV). Legionella pneumonia wasn′t detected by BCYE? plate.Conclusion BCYE? plate with antibiotics system of CCCV showed obvious suppression to Legionella pneumonia, and so that there was a low isolation ratio to Legionella pneumonia. But BCYE? plate with antibiotics system of DGVP and GVPC had a few suppression and showed a high isolatio ratio for Legionella pneumonia. Moreover, BCYE? plate with antibiotics system of DGVP and GVPC can effectively inhibit non-Legionella and increase isolation ratio of Legionella. They should be the first selection media for Legionella from environment and clinical samples.

To further investigate the mechanisms of action of icariin (ICA), we assessed the effects of ICA on the in vitro formation of cGMP and cAMP in isolated rabbit corpus cavernosum. Isolated segments of rabbit corpus cavernosum were exposed to increasing concentrations of ICA and the dose-dependent accumulation of cGMP and cAMP was determined in the tissues samples by means of 125I radioimmunoassay. Responses of the isolated tissues preparations to ICA were compared with those obtained with the reference compounds sildenafil (Sild). Furthermore, the effects of ICA on the mRNA expression of specific cGMP-binding phosphodiesterase type V (PDE5) in rat penis were also observed. After incubation with ICA for 6 h or 14 h respectively, the levels of PDE5 mRNA were examined by reverse transcriptase polymerase chain reaction (RT-PCR). The results showed that ICA increased cGMP concentrations directly (P < 0.05), but there was no significant effect on cAMP concentrations (P > 0.05). In the presence of sodium nitroprusside (SNP), a stimulatory agent of cGMP, both ICA and Sild increased cGMP concentrations with increasing dose (P < 0.01). Their EC50 was 4.62 (ICA) and 0.42 (Sild) micromol/L respectively. Under the same condition, ICA and Sild unaltered cAMP level significantly (P > 0.05). There were PDE5A1 and PDE5A2 mRNA expressions in rat corpus cavernosum with PDE5A2 being the dominant isoform. ICA could obviously inhibit these two isoforms mRNA expression in rat penis, and decrease PDE5A1 more pronouncedly (P < 0.01). The present study indicated that the aphrodisiac mechanisms of icariin involved the NO-cGMP signal transduction pathway, with increasing cGMP levels in the corpus cavernosum smooth muscle. The inhibitory effect of icariin on PDE5 mRNA expression, especially on PDE5A1, might account for its molecular mechanisms for its long-term activity.

AIM To test if "adventitium-derived relaxing factor"(ADRF) possesses species- and tissue-specificity and make preliminary research on proteins separated from the bath solution. METHODS Record the tension of aortic ring with and without periadventitial fat, induced by phenylephrine(Phe) and analyze the proteins extracted from the bath solution with SDS-PAGE electrophoresis. RESULTS ① In Sprague-Dawley rats, the concentration-response curve of Phe to rings without the periadventitial fat shifted to rightward, as compared to the curve of the intact aortic rings, which means periadventitial fat can reduce the contraction induced by Phe. The same phenomena as the above could be found in aortic ring of Wistar rats, guinea pigs, and rabbits. ② Moreover, the contraction induced by Phe was obviously reduced by moving adipose tissue from greater omentum into the bath solution. ③ The release of ADRF was strongly reduced by 10 μmol·L-1 genistein (tyrosine kinase inhibitor). But the effect of existed ADRF could not be counterposed by genistein. ④ Five protein bands were separated from the bath solution, with relative molecular mass 74.0, 59.8, 54.4, 28.7 and 13.8 ku. CONCLUSION ① ADRF is a non-species specific factor. ② The entire name of ADRF should change from "adventitium-derived relaxing factor" to "adipocyte-derived relaxing factor". ③ Some proteins which may include ADRF are separated from the bath solution.

Aim To explore the effects of lipoteichoic acid (LTA) induced delayed preconditioning (PC) on hypoxia-reoxygenation (H/R) injury of cultured human coronary artery endothelial cells (HCAECs), and to investigate the potential role of endogenous nitric oxide (NO) participated in the protective mechanism. Methods HCAECs were incubated for 2 h in a hypoxic atmosphere and reoxygenated for 4 h in a normoxic atmosphere. The delayed PC was induced by pretreatment with LTA assessed by the percentage of cellular injury with Trypan blue exclusion and by the amount of lactate dehydrogenase (LDH) in culture media. The NO level of the culture media was measured detect the expression of eNOS mRNA by RT-PCR method after cells were recovered from different points.Results LTA pretreatment significantly decreased the percentage of the killed cell and the concentration of LDH in media. Also, LTA pretreatment obviously raised the concentrations of NO in culture media. The protective effects of LTA were abrogated by pretreatment with N-monomethyl-L-arginine (L-NMMA).Moreover, the expression of eNOS mRNA was significantly upregulated after HCAECs exposure to LTA for 4 h following 2 h or 4 h recovery. Conclusion LTA could induce the delayed protection against H/R induced endothelial injury and dysfunction of cultured HCAECs. NO produced by eNOS acts initially as a trigger and subsequently as a mediator of delayed PC.

In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P > 0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal transduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.
Berberine/*pharmacology ; Connective Tissue/physiopathology ; Nitric Oxide Synthase/*biosynthesis ; Nitric Oxide Synthase/genetics ; Nitric Oxide Synthase Type I/biosynthesis ; Nitric Oxide Synthase Type I/genetics ; Nitric Oxide Synthase Type III/biosynthesis ; Nitric Oxide Synthase Type III/genetics ; Penile Erection/*physiology ; Penis/*metabolism ; Penis/physiology ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics

To investigate the effects of WIN 55,212-2 on IK in cultured rat trigeminal ganglion (TG) neurons, whole-cell patch clamp techniques were used to record the IK before and after WIN 55,212-2 perfusion at different concentrations. 30 μmol/L WIN 55,212-2 markedly (35.7 %±7.3%, P＜0. 01, n=8) inhibited IK currents, and the currents were partially recovered after washing.30μmol/L WIN 55,212-2 also induced a significant depolarizing shift in conductance-voltage parameters (control: V0.5 =10.43 ± 4.25 mV, k= 16.27±3.86; WIN 55,212-2: V0. 5 =24.71±3.91mV, k =16.69±2.75; n = 8, P＜0.01 for V0. 5). 0.01μmol/L WIN 55,212-2 slightly (27.0 %± 7.9 %, P＜0.05, n=7) increased IK currents, but had no significant change in conductance voltage parameters (control: V0.5 =10. 74±5. 27 mV, k=17. 33±2. 96; WIN 55,212-2: V0.5 =11.06±2.05 mV, k=19. 69±6. 60; n=7, P＞0.05 for V0.5 and k). These results suggested that WIN 55,212-2 has dual action, which might be through different receptors.