Polysaccharide isolated from wax apple suppresses ethyl carbamate-induced oxidative damage in human hepatocytes / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Wax apple (Syzygium samarangense) has received growing research interest for its high nutritional and medicinal value due to its constituents such as polysaccharide, organic acids, flavonoids, minerals, and other substances. In this study, wax apple polysaccharide (WAP) was isolated from this plant and its protective effect against ethyl carbamate (EC)‍-induced oxidative damage was evaluated in human hepatocytes (L02 cells). Firstly, a series of analyses such as high-performance liquid chromatography (HPLC), high-performance gel permeation chromatography (HPGPC), Fourier transform infrared spectroscopy (FT-IR), gas chromatography/mass spectrometry (GC/MS), and 1H and 13C nuclear magnetic resonance (NMR) were conducted to identify the structure of WAP. Thereafter, in vitro cell experiments were performed to verify the protective effects of WAP against EC-induced cytotoxicity, genotoxicity, and oxidative damage in L02 cells. Our results revealed that WAP is composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose in a molar ratio of 2.20:‍3.94:‍4.45:‍8.56:‍8.86:‍30.82:‍39.78:‍1.48. Using a combination of methylation and NMR spectroscopic analysis, the primary structure of WAP was identified as Araf-(1→, Glcp-(1→, →2)‍-Araf-(1→, →3)‍-Galp-(1→, →3)‍-Araf-‍(1→, and →6)‍-Galp-‍(1→. Cell experiments indicated that WAP exhibited significant protective effects on EC-treated L02 cells via suppressing cytotoxicity and genotoxicity, reducing reactive oxygen species (ROS) and O2•- formation, as well as improving mitochondrial membrane potential (MMP) and glutathione (GSH). In a nutshell, WAP has the potential as an important therapeutic agent or supplement for hepatic oxidative damage. Meanwhile, further studies are needed to prove the above effects in vivo at the biological and clinical levels.

Effect of folic acid coated-crosslinked urethane-doped polyester elastomer nerve conduit on promoting the repair of long distance peripheral nerve injury in rats / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effect of folic acid coated-crosslinked urethane-doped polyester elastomer (fCUPE) nerve conduit in repairing long distance peripheral nerve injury.@*METHODS@#Thirty-six 3-month-old male Sprague Dawley rats weighing 180-220 g were randomly assigned to 3 groups, each consisting of 12 rats: CUPE nerve conduit transplantation group (group A), fCUPE nerve conduit transplantation group (group B), and autologous nerve transplantation group (group C), the contralateral healthy limb of group C served as the control group (group D). A 20-mm-long sciatic nerve defect model was established in rats, and corresponding materials were used to repair the nerve defect according to the group. The sciatic function index (SFI) of groups A-C was calculated using the Bain formula at 1, 2, and 3 months after operation. The nerve conduction velocity (NCV) of the affected side in groups A-D was assessed using neuroelectrophysiological techniques. At 3 months after operation, the regenerated nerve tissue was collected from groups A-C for S-100 immunohistochemical staining and Schwann cell count in groups A and B to compare the level of nerve repair and regeneration in each group.@*RESULTS@#At 3 months after operation, the nerve conduits in all groups partially degraded. There was no significant adhesion between the nerve and the conduit and the surrounding tissues, the conduit was well connected with the distal and proximal nerves, and the nerve-like tissues in the conduit could be observed when the nerve conduit stents were cut off. SFI in group A was significantly higher than that in group C at each time point after operation and was significantly higher than that in group B at 2 and 3 months after operation ( P<0.05). There was no significant difference in SFI between groups B and C at each time point after operation ( P>0.05). NCV in group A was significantly slower than that in the other 3 groups at each time point after operation ( P<0.05). The NCV of groups B and C were slower than that of group D, but the difference was significant only at 1 month after operation ( P<0.05). There was no significant difference between groups B and C at each time point after operation ( P>0.05). Immunohistochemical staining showed that the nerve tissue of group A had an abnormal cavo-like structure, light tissue staining, and many non-Schwann cells. In group B, a large quantity of normal neural structures was observed, the staining was deeper than that in group A, and the distribution of dedifferentiated Schwann cells was obvious. In group C, the nerve bundles were arranged neatly, and the tissue staining was the deepest. The number of Schwann cells in group B was (727.50±57.60) cells/mm 2, which was significantly more than that in group A [(298.33±153.12) cells/mm 2] ( t=6.139, P<0.001).@*CONCLUSION@#The fCUPE nerve conduit is effective in repairing long-distance sciatic nerve defects and is comparable to autologous nerve grafts. It has the potential to be used as a substitute material for peripheral nerve defect transplantation.

Equol and its enantiomers inhibited urethane-induced lung cancer in mice / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effects and mechanisms of equol and its enantiomers on urethane-induced lung cancer in mice.@*METHODS@#A total of 120 5-week-old male C57BL/6 mice were randomly divided into 8 groups: lung cancer tumor control group (CG), genistein control group (GCG), low dose racemic equol group (LEG), high dose racemic equol group (HEG), low dose R-equol group (LRE), high dose R-equol group (HRE), low dose S-equol group (LSE) and high dose S-equol group (HSE). Urethane was injected subcutaneously twice a week for 4 weeks to induce lung cancer and then the mice were fed for 4 months. The body weight and food intake of each group were measured and recorded weekly. After the mice were sacrificed, the blood, livers and lungs of the mice were collected. The incidence of lung cancer in each group was recorded. The concentration of serum superoxide dismutase (SOD), malondialdehyde (MDA) and 8-hydroxydeoxygunosine (8-OHdG) were detected by the corresponding kits. Western blotting was used to detect the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in the livers. Between-group differences in body weight and food intake of the mice were compared using repeated measures ANOVA, and ANOVA for the differences between non-repeated measurements, with post hoc analysis using Tukey's method if there were between-group differences. Comparisons of categorical data were performed by chi-square test, and if there were differences between the groups, the Bonferroni method was used for pairwise comparison.@*RESULTS@#A total of 49 in the 120 mice developed lung cancer. The overall incidence of lung cancer was 40.8%. Compared with the control group, the incidence of lung cancers in each experimental group was lower, and the difference was statistically significant. The incidence of lung cancer in the high-dose experimental group was significantly lower than that in the low-dose experimental group. However, the incidence of lung cancer was similar in the three equol groups and the genistein group at the same dose. Compared with the control group, the high-dose experimental group had higher serum SOD concentration, lower MDA and 8-OHdG concentrations, and the differences were statistically significant. Western blotting analysis showed that the expression levels of Nrf2 protein in the experimental groups were higher than those in the control group except the low-dose racemic equol group, and the Nrf2 protein expression level in the high-dose equol groups was higher than that in the low-dose equol groups.@*CONCLUSION@#Racemic equol and its enantiomers mayinhibit lung carcinogenesis through antioxidant effects.

Advances in microbial enzymatic elimination of ethyl carbamate in Chinese rice wine / 生物工程学报

Ethyl carbamate (EC), a carcinogenic and teratogenic chemical that is widely distributed in various alcoholic beverages, has attracted much attention. Microbial enzymatic degradation of EC in rice wine is always efficient and attractive. In this review, we summarize the research progress and problems of microbial enzymatic elimination of EC in rice wine from three aspects: the mechanisms of EC formation in rice wine, the research progress of acid urease, and the research progress of urethanase. Then, we propose the corresponding strategies to solve the problems: screening new urethanase with satisfied enzyme properties, food-grade expression and directed evolution of the bifunctional Fe³⁺-dependent acid urease and acid urease used in combination with urethanase to eliminate both urea and EC in rice wine.

Electrical Activity of the Bladder Is Attenuated by Intravesical Inhibition of P2X2/3 Receptors During Micturition in Female Rats / 대한배뇨장애요실금학회지

PURPOSE: To simultaneously monitor electrical discharges in various bladder regions and the external urethral sphincter (EUS) during voiding contractions, and to assess the functional role of myogenic modulation of the lower urinary tract (LUT) by ionotropic purinergic receptors containing the P2X3 subunit. METHODS: Female Sprague-Dawley rats were anesthetized with urethane, and implanted with a suprapubic catheter for open cystometry. Flexible microelectrodes were placed ventrally in the bladder dome, upper bladder, lower bladder, and bladder base, along with the middle section of the exposed EUS. Intravesical P2X3-containing receptors were blocked with AF-323, a specific P2X3-P2X2/3 receptor antagonist. A digital electrophysiology amplifier was used to record electrical and cystometric signals throughout the LUT. RESULTS: Electrical activity in the LUT started before effective voiding contractions. Bladder pressure and electrical waveforms showed consistent out-of-phase activity when compared with the recordings made at the EUS. This pattern was also observed during voiding contractions in the presence of AF-353, supporting the hypothesis that during bladder distension, activation of P2X3-containing receptors is required for voiding contractions. Furthermore, the inhibition of P2X3-containing receptors significantly decreased the amplitude of electrical signals in the urinary bladder, but not the base or EUS. CONCLUSIONS: Our results provide novel information about the regulation of the micturition process by P2X3-containing receptors located in the inner layers of the bladder.

Effect of S-methyl-l-thiocitrulline dihydrochloride on rat micturition reflex

ABSTRACT Objective: To evaluate the effect of neuronal nitric oxide synthase on the striated urethral sphincter and the urinary bladder. Materials and Methods: A coaxial catheter was implanted in the proximal urethra and another one in the bladder of female rats, which were anesthetized with subcutaneous injection of urethane. The urethral pressure with saline continuous infusion and bladder isovolumetric pressure were simultaneously recorded. Two groups of rats were formed. In group I, an intrathecal catheter was implanted on the day of the experiment at the L6-S1 level of the spinal cord; in group II, an intracerebroventricular cannula was placed 5-6 days before the experiment. Results: It was verified that the group treated with S-methyl-L-thio-citrulline, via intrathecal pathway, showed complete or partial inhibition of the urethral sphincter relaxation and total inhibition of the micturition reflexes. The urethral sphincter and the detrusor functions were recovered after L-Arginine administration. When S-methyl-L-thio-citrulline was administered via intracerebroventricular injection, there was a significant increase of urethral sphincter tonus while preserving the sphincter relaxation and the detrusor contractions, at similar levels as before the use of the drugs. Nevertheless there was normalization of the urethral tonus when L-Arginine was applied. Conclusions: The results indicate that, in female rats anaesthetized with urethane, the nNOS inhibitor administrated through the intrathecal route inhibits urethral sphincter relaxation, while intracerebroventricular injection increases the sphincter tonus, without changing bladder function. These changes were reverted by L-Arginine administration. These findings suggest that the urethral sphincter and detrusor muscle function is modulated by nitric oxide.

Degradation of urea and ethyl carbamate in Chinese Rice wine by recombinant acid urease / 生物工程学报

Ethyl carbamate (EC) as a potential carcinogen commonly exists in traditional fermented foods. It is important eliminate urea that is the precursors of EC in many fermented foods, including Chinese Rice wine. On the basis of achieving high-level overexpression of food-grade ethanol-resistant acid urease, we studied the hydrolysis of urea and EC with the recombinant acid urease. Recombinant acid urease showed degraded urea in both the simulated system with ethanol and Chinese Rice wine (60 mg/L of urea was completely degraded within 25 h), indicating that the recombinant enzyme is suitable for the elimination of urea in Chinese Rice wine. Although recombinant acid urease also has degradation catalytic activity on EC, no obvious degradation of EC was observed. Further investigation results showed that the Km value for urea and EC of the recombinant acid urease was 0.7147 mmol/L and 41.32 mmol/L, respectively. The results provided theoretical foundation for realizing simultaneous degradation of urea and EC.

Caryocar brasiliense camb protects against genomic and oxidative damage in urethane-induced lung carcinogenesis

The antioxidant effects of Caryocar brasiliense Camb, commonly known as the pequi fruit, have not been evaluated to determine their protective effects against oxidative damage in lung carcinogenesis. In the present study, we evaluated the role of pequi fruit against urethane-induced DNA damage and oxidative stress in forty 8-12 week old male BALB/C mice. An in vivo comet assay was performed to assess DNA damage in lung tissues and changes in lipid peroxidation and redox cycle antioxidants were monitored for oxidative stress. Prior supplementation with pequi oil or its extract (15 µL, 60 days) significantly reduced urethane-induced oxidative stress. A protective effect against DNA damage was associated with the modulation of lipid peroxidation and low protein and gene expression of nitric oxide synthase. These findings suggest that the intake of pequi fruit might protect against in vivo genotoxicity and oxidative stress.

The Mechanism of Low Temperature Burn and Clinical Cases

PURPOSE: This study was designed to better understand the mechanism of low temperature burn and to show clinical cases of low temperature burn. METHODS: The local temperature increase of electric pad was investigated at 4 different surface cooling conditions. Blocks (5x5x2 cm3) made of silicone rubber, aluminum, or urethane foam were placed on the top of the electric pad, and temperature between the blocks and electric pad was measured up to 7 hours after switching on maximally (level 7). Each block has different thermal conductivity (TC) and TC of silicone rubber (0.2 W/m.degrees C) is similar to TC of human skin (0.37 W/m.degrees C). TC of aluminum is higher and TC of urethane foam is lower than TC of human skin. Experiments were performed on two occasions with or without a blanket covering over the electric pad and blocks. RESULTS: The initial surface temperature (18degrees C) of the electric pad under the silicone rubber block was elevated to 36.5degrees C at 1 hour, 41.8degrees C at 3 hours, 44.2degrees C at 5 hours, and 45.5degrees C at 7 hours. After covering the electric pad and blocks with a blanket, the temperature of the electric pad under the silicone rubber block was elevated to 40.9degrees C at 1 hour, 51.8degrees C at 3 hours, 56.1degrees C at 5 hours and 58.1degrees C at 7 hours. Under the same conditions, surface temperatures under the urethane foam and aluminum blocks were 70.8degrees C and 50.degrees C respectively at 7 hours. CONCLUSION: The local temperature increase of electric pad was dependent on the surface cooling conditions, heating time and blanket covering over the electric pad. The surface temperature increased to 56.1degrees C at 5 hours after blanket covering over the silicone block which temperature can cause severe injuries on the human skin within a minute.

Intraperitoneal co-administration of low dose urethane with xylazine and ketamine for extended duration of surgical anesthesia in rats / 한국실험동물학회지

Procedures involving complex surgical techniques in rats, such as placement of abdominal aortic graft require extended duration of surgical anesthesia, which often can be achieved by repeated administrations of xylazine-ketamine combination. However such repeated anesthetic administration, in addition to being technically challenging, may be associated with potential adverse events due to cumulative effects of anesthesia. We report here the feasibility of using urethane at low dose (~1/10 the recommended anesthetic dose) in combination with a xylazine-ketamine mix to achieve an extended duration of surgical anesthesia in rats. The anesthesia induction phase was quick and smooth with an optimal phase of surgical anesthesia achieved for up to 90 minutes, which was significantly higher compared to that achieved with use of only xylazine-ketamine combination. The rectal temperature, heart rate and respiratory rate were within the physiological range with an uneventful recovery phase. Post surgery the rats were followed up to 3 months without any evidence of tumor or any other adverse effects related to the use of the urethane anesthetic combination. We conclude that low dose urethane can be effectively used in combination with xylazine and ketamine to achieve extended duration of surgical anesthesia up to 90 minutes in rats.

Myeloid-derived suppressor cells and associated events in urethane-induced lung cancer

OBJECTIVES: Myeloid-derived suppressor cells contribute to the immunosuppressive microenvironment during tumor development and limit the efficacy of cancer immunotherapy. Identifying myeloid-derived suppressor cells and associated factors is the first step in creating strategies to reverse the suppressive effects of these cells on the immune system. METHODS: To induce lung cancer, we administered 2 doses of urethane to BALB/c mice and observed these animals for 120 days. After this period, we evaluated the percentage of myeloid-derived suppressor cells in the blood, lung and bone marrow. The expression of alpha-smooth muscle actin, transforming growth factor-β, Toll-like receptor 2, Toll-like receptor 4, and interleukin-6 was also determined in the lung tissue. RESULTS: Myeloid-derived suppressor cells were increased in all evaluated tissues after lung cancer development in association with increased Toll-like receptor 4 expression and decreased interleukin-6 expression in the lung. We observed alpha-smooth muscle actin and transforming growth factor-β expression in lung nodules. CONCLUSIONS: We believe that the early diagnosis of cancer through determining the blood levels of myeloid-derived suppressor cells followed by the depletion of these cells should be further investigated as a possible approach for cancer treatment. .

Caracterização de resinas para base de prótese e reembasamento: propriedades físico-químicas e mecânicas / Characterization of denture base and reline resins: physical, chemical and mechanical properties

Este estudo avaliou propriedades físico-químicas e mecânicas de resinas para base de prótese, uma fotoativada (Eclipse - E) à base de UDMA e outra termicamente ativada por micro-ondas (Nature Cryl MC - NC) à base de PMMA, e um reembasador quimicamente ativado (Tokuyama Rebase Fast II - TR II) à base de PEMA. Propriedades viscoelásticas (E', tan δ e Tg), contração linear de polimerização (CLP), sorção (Sor) e solubilidade (Sol) em água e em saliva artificial, grau de conversão (GC) e coeficiente de inchamento (CI) foram avaliados para a caracterização dos polímeros. A resistência à flexão dos materiais intactos (E, NC, TR II) e reembasados (E-E, E-TRII, NC-NC- NC-TR II) também foi avaliada. As propriedades viscoelásticas foram avaliadas em corpos-de-prova retangulares (64 x 10 x 3,3 mm), submetidos (n=2) à análise térmica dinâmico-mecânica (DMTA) em dois ciclos de varredura após confecção (controle) e armazenagem em saliva. O módulo de armazenamento (E') e o amortecimento mecânico (tan δ) a 37 ºC e a temperatura de transição vítrea (Tg) foram registrados durante o 1º ciclo da DMTA. A CLP (%) foi avaliada (n=10), em projetor de perfil (Nikon 6C), em corpos-de-prova circulares (50 x 0,5 mm). A Sor e a Sol (µg/mm3) foram mensuradas (n=5) seguindo as recomendações da ISO 1567. O GC (%) foi avaliado (n=5) por espectroscopia de infravermelho por transformadas de Fourier (32 leituras; resolução 4,0 cm-1 ). O coeficiente de inchamento foi realizado (n=5) de acordo com a teoria de Flory-Rhener. Os ensaios mecânicos de flexão (0,5 mm/min) foram realizados (n=10) em corpos-de-prova (64 x 10 x 3,3 mm) intactos ou reembasados e a resistência (MPa) calculada na tensão máxima (RFM) e no limite de proporcionalidade (RFLP). Os dados foram avaliados por ANOVA, seguida por Tukey HSD (α=0,05) ou Dunnett (α=0,05). As resinas E e NC apresentaram similar E', superior a TR II. O tan δ foi ordenado como TR II > NC > E. A Tg não foi alterada após armazenagem em saliva artificial. Os maiores valores de Tg nos grupos controle e armazenados foram apresentados, respectivamente, pelos materiais E e NC. Houve deslocamento dos picos de tan δ após o segundo ciclo de DMTA. Independente do meio de imersão, a Sor (µg/mm3 ) foi ordenada em NC > E > TR II. A armazenagem em saliva reduziu a Sol (µg/mm3 ) dos materiais. A resina E exibiu os menores valores de CLP, CI e o maior GC. NC exibiu a maior CLP e CI. TR II exibiu valores intermediários de CLP, CI e o menor GC. Os maiores valores de RFM e RFLP foram produzidos por E. A RFM e RFLP dos materiais reembasados foi ordenada em E-E > NC-NC > E-TRII> NC-TR II. A armazenagem em saliva não influenciou a resistência à flexão dos materiais intactos ou reembasados. No geral, a resina para base de prótese E apresentou propriedades físico-químicas e mecânicas superiores à NC e TR II

This study evaluated the physical-chemical and mechanical properties of denture base resins, one UDMA light-activated (Eclipse-E) and one PMMA heat-polymerized (Nature Cryl MC - NC). The PEMA autopolymerizing reliner (Tokuyama Rebase Fast II - TR II) was also evaluated. Viscoelastic properties (E', tan δ e Tg), linear shrinkage polymerization (LPS), sorption (Sor) and solubility (Sol) in water and in artificial saliva, degree of conversion (DC) and coefficient of swelling (CS) were employed for polymer characterization. The flexural strength of intact (E, NC, TR II) and relined samples (E-E, E-TRII, NC-NC- NC-TR II) was also made. The viscoelastic properties were evaluated by two cycles of dynamic mechanical thermal analysis (DMTA) on each rectangular (64 x 10 x 3.3 mm) samples (n=2). The storage modulus (E') and loss tangent (tan δ) at 37 ºC and the glass transition temperature (Tg) were recorded from the 1st DMTA cycle. LPS (%) was evaluated (n=10) by a Nikon 6C optical comparator, on circular samples (50 x 0.5 mm). Sor and Sol (µg/mm3 ) were measured (n=6) according to ISO 1567. DC (%) was evaluated (n=5) by FTIR spectroscopy (32 scans; resolution 4.0 cm-1). CS was evaluated (n=5) by Flory-Rhener theory. A three-point flexural tests (0.5 mm/min) was applied (n=10) on rectangular intact and relined samples. The ultimate flexural strength (FSU) and the flexural strength at the proportional limit (FSPl) were recorded in MPa. Data were analyzed with ANOVA, followed by Tukey HSD (α=0.05) ou Dunnett (α=0.05). E and NC had similar E', higher than TR II. Tan δ was arranged as TR II > NC > E. The Tg was not affected after saliva storage. The higher Tg values were obtained for E and NC. Tan δ peaks were shifted after 2 DMTA cycles. Regardless the medium immersion, Sor (µg/mm3 was arranged as NC > E > TR II. Saliva storage reduced Sol (µg/mm3) of the materials. E showed the lowest values of LPS, CS and the highest value of DC. NC showed the highest LPS and CS.TR II showed intermediated values of LPS, CS and the lowest DC. The highest FSU and FSPl values were exhibited by E. The FSU and FSPl of relined samples were arranged as E-E > NC-NC > E-TRII > NC-TR II. Saliva storage did not affect the flexural strength of intact and relined samples. Overall, the denture base resin E showed higher physicochemical and mechanical properties than NC and TR II

In vitro comparison of two different materials for the repair of urethan dimethacrylate denture bases

PURPOSE: The purpose of this in vitro study was to investigate the flexural properties of a recently introduced urethane dimethacrylate denture base material (Eclipse) after being repaired with two different materials. MATERIALS AND METHODS: Two repair groups and a control group consisting of 10 specimens each were generated. The ES group was repaired with auto-polymerizing polymer. The EE group was repaired with the Eclipse. The E group was left intact as a control group. A 3-point bending test device which was set to travel at a crosshead speed of 5 mm/min was used. Specimens were loaded until fracture occurred and the mean displacement, maximum load, flexural modulus and flexural strength values and standard deviations were calculated for each group and the data were statistically analyzed. The results were assessed at a significance level of P.05) was found between the mean values of Group ES and EE. There was a statistically significant positive relation (P<.01) between the displacement and maximum load of Group ES (99.5%), Group EE (94.3%) and Group E (84.4%). CONCLUSION: The more economic and commonly used self-curing acrylic resin can be recommended as an alternative repair material for Eclipse denture bases.

Comparison of tonal response properties of primary auditory cortex neurons of adult rats under urethane and ketamine anesthesia / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare tonal response properties of neurons in the primary auditory cortex of Sprague-Dawley rats anesthetized with urethane and ketamine-xylazine.</p><p><b>METHODS</b>Forty-five female Sprague-Dawley rats (200-250 g) were randomized into two groups and anesthetized with urethane or ketamine-xylazine. Tone pips were chosen as the stimuli to obtain the action potentials of the single neurons by in vivo cell-attached recording. The features of the action potentials were extracted with Matlab software to comparatively analyze the acoustic response properties of the neurons between the two anesthetic groups.</p><p><b>RESULTS</b>The Q values and the characteristic frequencies were independent of the types of anesthetic agents, but with urethane anesthesia, the neurons tended to have higher minimum thresholds, lower spontaneous firing rates, longer response latencies, and more frequent occurrence of tuning with stronger inhibition compared to those in ketamine-xylazine group.</p><p><b>CONCLUSION</b>Urethane and ketamine might have no obvious impact on the transmission pathway of frequency tuning from the periphery to the auditory cortex, but neurons from rats with urethane anesthesia receive enhanced inhibition mediated by the interneurons or have a lower intrinsic excitability.</p>

Study on content of ethyl carbamate in yellow rice wine and its change in Zhejiang province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand the content status of ethyl carbamate (EC) in yellow rice wine and the changes in storage period and shelf life in Zhejiang province.</p><p><b>METHODS</b>A total of 475 samples of yellow rice wine purchased randomly from supermarkets and food stores in Zhejiang province during 2008-2012, and 49 samples collected from manufacturers were measured for EC content. The sample collected from manufacturers by filter sterilization was placed at 4 °C, room temperature and 37 °C for 400 d, respectively;a bottled wine and a wine in bag were bought from market were placed for 400 d in room temperature to conduct shelf life storage test, and measure the content in every point in 2011. The EC of the samples was determinated by gas chromatography-mass spectrometry after the samples were diluted with D5-EC isotope dilution technique, and purified by alkaline diatomite solid phase extraction column.</p><p><b>RESULTS</b>The overall detection rate of EC was 99% (472/475) in yellow rice wine of Zhejiang province in 2008-2012, the median value was 70-112 µg/kg, the 90th percentile was 190-333 µg/kg, the 95th percentile was 214-393 µg/kg, and the maximum value was 430-515 µg/kg. The content of EC was increased gradually along with the increasing of storage age in commercially yellow rice wine, and the average content of EC were positively correlated with storage age(r = 0.988). The contents of EC in yellow rice wine after sterilization increased from 74 µg/kg to 86 µg/kg, 127 µg/kg and 509 µg/kg at 4 °C, room temperature and 37°C, respectively for 400 d storage, the differences had statistical significance (F = 14.73, P < 0.01). The content of EC in yellow rice wines in shelf life, which stored in room temperature with bottle and bag package, was decreased slightly with increasing storage time in the beginning, from 215 to 184 µg/kg and 196 to 158 µg/kg, respectively, and increased again with increasing storage time after 250 d, with 252 µg/kg and 210 µg/kg in bottle and bag package after 400 d, respectively, the differences had statistical significance (Z = 2.37, P < 0.05).</p><p><b>CONCLUSION</b>EC is widespread in rice wine, the content of EC was correlated with storage time and temperature.</p>

Detection of methyl carbamate and ethyl carbamate in yellow rice wine by gas chromatography-mass spectrometry / 中华预防医学杂志

<p><b>OBJECTIVE</b>To establish the method of simultaneous determination of methylcarbamate (MC) and ethylcarbamate (EC) in yellow rice wine by gas chromatography-mass spectrometry (GC/MS).</p><p><b>METHODS</b>MC and EC in yellow rice wine were derived by 9-xanthydrol, and then the derivants were detected by GC/MS; and quantitatively analyzed by D5-EC isotope internal standard method.</p><p><b>RESULTS</b>The linearity of MC and EC ranged from 2.0 µg/L to 400.0 µg/L, with correlation coefficients at 0.998 and 0.999, respectively. The limits of quantitation (LOQ) and detection (LOD) were 0.67 and 2.0 µg/kg. When MC and EC were added in yellow rice wine at the range of 2.0-300.0 µg/kg, the intraday average recovery rate was 78.8%-102.3%, relative standard deviation was 3.2%-11.6%; interday average recovery rate was 75.4%-101.3%, relative standard deviation was 3.8%-13.4%. 20 samples of yellow rice wine from supermarket were detected using this method, the contents of MC were in the range of ND (no detected) to 1.2 µg/kg, the detection rate was 6% (3/20), the contents of EC in the range of 18.6 µg/kg to 432.3 µg/kg, with the average level at 135.2 µg/kg.</p><p><b>CONCLUSION</b>The method is simple, rapid and useful for simultaneous determination of MC and EC in yellow rice wine.</p>

Effects of Mirodenafil, a Phosphodiesterase-5 Inhibitor, on Female Rat Bladder in a Partial Bladder Outlet Obstruction Model: Physiological and Immunohistochemical Aspects

PURPOSE: We investigated the effects of mirodenafil, a phosphodiesterase-5 inhibitor developed in South Korea, on the female rat bladder in a partial bladder outlet obstruction (BOO) model. MATERIALS AND METHODS: Thirty-six female Sprague-Dawley rats were divided into four groups: the control group, BOO without medication group, BOO with mirodenafil 1 mg/kg group, and BOO with mirodenafil 4 mg/kg group. Mirodenafil was administered orally for 2 weeks after the induction of BOO. Two weeks after BOO, the rats in each group underwent cystometry under urethane anesthesia. After cystometry, the bladder was excised to perform immunohistochemical staining for connexin 43. RESULTS: The three BOO groups showed significant increases in mean bladder weight compared with the control group. Baseline pressure, threshold pressure, and maximum contraction pressure were not significantly different between the four groups. Although the contraction interval was decreased in all BOO groups compared with the control group, it was prolonged in the two groups treated with mirodenafil compared with the untreated BOO group. In the immunohistochemical examination, connexin 43 staining intensity in the lamina propria increased in the three BOO groups compared with the control group. The two groups treated with mirodenafil, however, showed decreased connexin 43 staining compared with the untreated BOO group. CONCLUSIONS: Mirodenafil may increase the contraction intervals of female rat bladders in a partial BOO model. Decreasing bladder overactivity by mirodenafil may be related to intracellular communication mechanisms involving connexin 43.

Effect of aconiti lateralis radix praeparata and taraxaci herba on Chinese medicine signs and symptoms of urethane-induced lung cancer in mice / 中国中药杂志

<p><b>OBJECTIVE</b>To study Chinese medicine (CM) signs and symptoms of urethane-induced lung cancer in mice, and observe the effect of Aconiti Lateralis Radix Praeparata and Taraxaci Herba on symptoms in mice and tumor progress.</p><p><b>METHOD</b>The mice were intraperitoneally injected with urethane twice a week for consecutively five weeks to establish a lung cancer model. The changes in their appearance, body temperature and auricle microcirculation were observed in carcinogenic process. CM signs and symptoms of urethane-induced lung cancer in mice were evaluated with energy metabolism, erythrocytic ATP emzymatic activity and hemorrheological index. During the tumor model was induced, Aconiti Lateralis Radix Praeparata and Taraxaci Herba were used to treat the mice and observe their effect on symptoms in mice and tumor progress.</p><p><b>RESULT</b>During urethane was used to induce lung cancer, the mice had gradually become chill, lazy, hunched, with reduction in temperature, cyanosis in auricle and tail. Meanwhile, their energy metabolism and erythrocytic ATP enzymatic activity reduced, whereas their whole blood viscosity and erythrocytic aggregate index increased. Taraxaci Herba showed an effect on enhancing above symptoms and signs but had no effect on tumor progress. Aconiti Lateralis Radix Praeparata showed an effect on reducing above symptoms and signs and preventing tumor progress.</p><p><b>CONCLUSION</b>Mice with urethane-induced lung cancer show CM signs and symptoms of congealing cold with blood stasis. The treatment with Aconiti Lateralis Radix Praeparata can alleviate symptoms and signs in mice and prevent tumor progress.</p>

Clinical Application of Polyether Ester Urethane in Endonasal Dacryocystorhinostomy

PURPOSE: To evaluate the clinical effect of intraoperative application of polyether ester urethane (Nasopore(R)) in endonasal dacryocystorhinostomy. METHODS: Endonasal dacryocystorhinostomy was performed on 77 eyes diagnosed with nasolacrimal duct obstruction between January 2010 and February 2011. Nasopore(R) was applied to the newly-formed internal lacrimal opening in the experimental group (41 eyes), and vaseline gauze was applied in the control group (36 eyes). For the evaluation of clinical effects regarding postoperative adhesion and stenosis of the internal lacrimal opening, subjective symptom improvement, lacrimal irrigation tests, and endoscopic examinations were performed at 1 week, 2 weeks, 1 month, 3 months, and 6 months, postoperatively. RESULTS: In subjective symptom improvement and lacrimal irrigation tests, differences between the 2 groups were not statistically significant. In endoscopic findings, the Nasopore(R) group showed significantly lower severity of adhesion and stenosis of the internal lacrimal opening at 1 week, 2 weeks, and 1 month after operation (p < 0.05). CONCLUSIONS: Application of the Nasopore(R) may effectively reduce initial postoperative adhesion or stenosis of the internal lacrimal opening after endonasal dacryocystorhinostomy and has usefulness as an auxiliary method.

Occupational Neurotoxic Diseases in Taiwan

Occupational neurotoxic diseases have become increasingly common in Taiwan due to industrialization. Over the past 40 years, Taiwan has transformed from an agricultural society to an industrial society. The most common neurotoxic diseases also changed from organophosphate poisoning to heavy metal intoxication, and then to organic solvent and semiconductor agent poisoning. The nervous system is particularly vulnerable to toxic agents because of its high metabolic rate. Neurological manifestations may be transient or permanent, and may range from cognitive dysfunction, cerebellar ataxia, Parkinsonism, sensorimotor neuropathy and autonomic dysfunction to neuromuscular junction disorders. This study attempts to provide a review of the major outbreaks of occupational neurotoxins from 1968 to 2012. A total of 16 occupational neurotoxins, including organophosphates, toxic gases, heavy metals, organic solvents, and other toxic chemicals, were reviewed. Peer-reviewed articles related to the electrophysiology, neuroimaging, treatment and long-term follow up of these neurotoxic diseases were also obtained. The heavy metals involved consisted of lead, manganese, organic tin, mercury, arsenic, and thallium. The organic solvents included n-hexane, toluene, mixed solvents and carbon disulfide. Toxic gases such as carbon monoxide, and hydrogen sulfide were also included, along with toxic chemicals including polychlorinated biphenyls, tetramethylammonium hydroxide, organophosphates, and dimethylamine borane. In addition we attempted to correlate these events to the timeline of industrial development in Taiwan. By researching this topic, the hope is that it may help other developing countries to improve industrial hygiene and promote occupational safety and health care during the process of industrialization.