In vitro characterization and in vivo performance of mefenamic acid-sodium diethyldithiocarbamate based liposomes

Mefenamic acid (MFA) is a hydrophobic drug with low dissolution rate. This study aimed to develop stable and reproducible aqueous formulations of MFA using liposomes as drug carriers. The drug entrapment, particles size and drug release profiles, and stability and reproducibility of the liposomes were determined. In addition, the maximum tolerated dose (MTD) was determined in rats via the oral and intraperitoneal routes of administration. Also, the anti-inflammatory efficacy of these liposomes was evaluated using carrageenan-induced paw edema model in rats. MFA-DDC based liposomes demonstrated a drug entrapment efficacy of 93.6%, particles size of 170.9 nm, and polydispersity index of 0.24 which were not statistically affected when stored in room and refrigerated temperatures for at least 4 weeks. The MTD of the intraperitoneally administrated MFA-loaded liposomes was 20 mg MFA/kg, whereas for those of oral administrations, it was up to 80 mg MFA/kg. Intraperitoneal dose (80 mg MFA/kg) of MFA-DDC liposomes induced extrapyramidal symptoms associated with significant elevation in serum potassium and muscle enzymes. Moreover, significant inhibition of paw edema was demonstrated by the oral and intraperitoneal routes. These findings suggest that MFA-DDC based liposomes are an effective formulation of MFA and recommend the use of bioequivalence assessments with commercial formulations.

Tendencias en la mortalidad por cáncer en México de 1980 a 2011 / Cancer mortality trends in Mexico, 1980-2011

Objetivo. Evaluar las tendencias de mortalidad por cáncer en México entre 1980 y 2011. Material y métodos. Se calcularon las tasas de mortalidad ajustadas por edad y sexo para todos los cánceres y para las 15 localizaciones más frecuentes mediante el método directo y tomando como población estándar la población mundial de 2010. Las tendencias en las tasas de mortalidad y el cambio porcentual anual para cada tipo de cáncer se estimaron a través de un modelo de regresión joinpoint. Resultados. A partir de 2004 y como consecuencia de la reducción de la mortalidad por cáncer de pulmón (-3.2% en hombres y -1.8% en mujeres), estómago (-2.1% en hombres y -2.4% en mujeres) y cérvix (-4.7%), se observó una disminución significativa (~1% anual) en la mortalidad por cáncer en general tanto en el grupo de todas las edades como en el de 35 a 64 años para ambos sexos. La mortalidad por otros cánceres como el de mama y el de ovario, en las mujeres o el de próstata, en los hombres, mostró un aumento sostenido. Conclusiones. Algunas de las reducciones en la mortalidad por cáncer pueden ser parcialmente atribuidas a la efectividad de los programas de prevención establecidos. Sin embargo, se requiere implementar registros adecuados de cáncer con base poblacional para evaluar el impacto real de estos programas, así como diseñar y evaluar intervenciones innovadoras que permitan desarrollar políticas de prevención más costo-efectivas.

Objective. To evaluate trends in cancer mortality in Mexico between 1980-2011. Material and methods. Through direct method and using World Population 2010 as standard population, mortality rates for all cancers and the 15 most frequent locations, adjusted for age and sex were calculated. Trends in mortality rates and annual percentage change for each type of cancer were estimated by joinpoint regression model. Results. As a result of the reduction in mortality from lung cancer (-3.2% -1.8% in men and in women), stomach (-2.1% -2.4% in men and in women) and cervix (-4.7%); since 2004 a significant (~1% per year) decline was observed in cancer mortality in general, in all ages, and in the group of 35-64 years of both sexes. Other cancers such as breast and ovarian cancer in women; as well as for prostate cancer in men, showed a steady increase. Conclusions. Some of the reductions in cancer mortality may be partially attributed to the effectiveness of prevention programs. However, adequate records of population-based cancer are needed to assess the real impact of these programs; as well as designing and evaluating innovative interventions to develop more cost-effective prevention policies.

A Study on Anlaysis of Patch Test Positive Reactivity according to the Reading Time with T.R.U.E. TEST(R) / 대한피부과학회지

BACKGROUND: The patch test is widely used for diagnosis of allergic contact dermatitis. However, nearly half of positive reactions can be observed only on day 2 or day 4 and it is difficult to interpret these reactions. OBJECTIVE: The purpose of this study is to assess the frequency of transient and delayed reactions in TRUE-test and detect common antigens that provoke these reactions. METHODS: A total of 311 patients with allergic contact dermatitis were evaluated by TRUE-test between Jan 2007 and December 2011. Records of patch test results of day 2 and day 4 were reviewed and analyzed. RESULTS: A total 311 cases of T.R.U.E. TEST(R) records (male 79, female 232) were analyzed. Persistent reactions were observed in 80.1% patients tested, transient reactions were observed in 18.3%, and delayed reaction in 5%. Frequent allergens which showed transient reactions were cobalt dichloride (2.9%), nickel sulfate (2.2%), thiomersal (1.9%), and carba mix (1.6%), in order of frequency. Allergens which showed delayed reactions were nickel sulfate (0.3%), fragrance mix (0.3%), p-tert-butylphenol formaldehyde resin (0.43). CONCLUSION: Our results showed a relatively high frequency of transient reaction in T.R.U.E. TEST(R). This suggests that additional reading at day 4 in the patch test would be of value.

Antioxidant Effect of Captopril and Enalapril on Reactive Oxygen Species-Induced Endothelial Dysfunction in the Rabbit Abdominal Aorta

BACKGROUND: Reactive oxygen species (ROS) are known to be related to cardiovascular diseases. Many studies have demonstrated that angiotensin-converting enzyme inhibitors have beneficial effects against ROS. We investigated the antioxidant effect of captopril and enalapril in nitric oxide mediated vascular endothelium-dependent relaxations. MATERIALS AND METHODS: Isolated rabbit abdominal aorta ring segments were exposed to ROS by electrolysis of the organ bath medium (Krebs-Henseleit solution) after pretreatment with various concentrations (range, 10-5 to 3x10-4 M) of captopril and enalapril. Before and after electrolysis, the endothelial function was measured by preconstricting the vessels with norepinephrine (10-6 M) followed by the cumulative addition of acetylcholine (range, 3x10-8 to 10-6 M). The relevance of the superoxide anion and hydrogen peroxide scavenging effect of captopril and enalapril was investigated using additional pretreatments of diethyldithiocarbamate (DETCA, 0.5 mM), an inhibitor of Cu/Zn superoxide dismutase, and 3-amino-1,2,4-triazole (3AT, 50 mM), an inhibitor of catalase. RESULTS: Both captopril and enalapril preserved vascular endothelium-dependent relaxation after exposure to ROS in a dose-dependent manner (p<0.0001). Pretreatment with DETCA attenuated the antioxidant effect of captopril and enalapril (p<0.0001), but pretreatment with 3AT did not have an effect. CONCLUSION: Both captopril and enalapril protect endothelium against ROS in a dose-dependent fashion in isolated rabbit abdominal aortas. This protective effect is related to superoxide anion scavenging.

Patch Test (T.R.U.E. Test) Results in Patients with Allergic Contact Dermatitis: 2007~2011, Chungcheongnamdo / 대한피부과학회지

BACKGROUND: A number of skin manifestations in patients with allergic contact dermatitis result from sensitization with specific allergens, and patch testing is used as a diagnostic means of identifying theses allergens. In Korea, the commercial patch test panel, the TRUE-test, has been available since 2005. However, there have been few reports regarding the results of the TRUE-test. OBJECTIVE: The purpose of this study was to analyze the type, frequency, and changes in common contact allergens in Korea using the TRUE test. METHODS: A total of 311 patients with allergic contact dermatitis were evaluated by the TRUE test between January 2007 and December 2011 at Soonchunhyang hospital. Patch test reading was performed on day 2 and day 4. RESULTS: A total of 311 cases of TRUE test records (male 79, female 232) were compiled and analyzed. The highest age distribution was the 4th decade in females. The face, with exception of the lips, was the most frequently affected site (40.2%). Overall, 58.8% of patients had at least on positive reaction, and the most common allergens were nickel sulfate (31.8%), p-phenylenediamine (13.5%), cobalt chloride (10.0%), thiomersal (7.4%), and carba mix (5.5%). Nickel allergen displayed higher positive rates than the rates in other countries. CONCLUSION: There was no significant difference in the overall positive rate of patch test results compared with recent studies. However, we confirmed that metal-related allergens remain the most common, and that the results provide the basis for the use of the TRUE test in patients with contact dermatitis in Korea.

Avaliação in vitro de fármacos pró-oxidantes sobre o Schistosoma mansoni / In vitro evaluation of drugs pro-oxidants on Schistosoma mansoni

Segundo a Organização Mundial de Saúde (2002), a esquistossomose é a segunda maior doença tropical, causadora de 200 a 300 mil mortes por ano. Mesmo apresentando alguns quimioterápicos eficazes para o tratamento, como o praziquantel (PZQ) e a oxamniquina (OXQ), ocorrem muitos casos refratários e efeitos colaterais. Diante deste contexto, é necessária a busca racional de novos medicamentos e combinações para o tratamento desta doença. Uma possível solução é o estudo de drogas relacionadas com o estresse oxidativo do patógeno. Dentre estas podem ser analisadas: a artemisinina (ART) , que induz uma maior produção de radicais livres por inibição da formação da hemozoína em Plasmodium falciparum; a butionina sulfoximina (850), que impede a produção da glutationa; além do dietilditiocarbamato de sódio (DDC), que age como inibidor das superóxido dismutases. Portanto, o objetivo deste trabalho foi testar in vitro essas drogas, isoladas e combinadas, analisando a atividade das superóxido dismutases, alterações morfológicas e produção de hemozoína em vermes adultos, além de avaliar a toxicidade em esplenócitos. A ART apresentou efeito esquistossomicida em concentrações elevadas. O DDC mostrou um efeito esquistossomicida satifatório e inibiu as superóxido dismutases. Quanto à associação ART - DDC, esta inibiu a formação da hemozoína, apresentou danos nos tegumentos dos vermes e não apresentou citotoxicidade significativa. Estes resultados indicam que estas drogas são viáveis para estudos in vivo, podendo ser uma nova alternativa quimioterápica para esta patologia.

Clinical Results of Chemotherapy based Treatment in Retinoblastoma Patients: A Single Center Experience / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Retinoblastoma is the most common intraocular malignancy in children. Since the 1990s, chemotherapy was indicated for intraocluar disease to reduce the frequency of enucleation and spare the complications associated with external beam radiation. In this study, we analyzed treatment results of retinoblastoma in our institute. MATERIALS AND METHODS: Datas from children diagnosed with retinoblastoma and treated at Seoul National University Children's Hospital between 1986 and 2008 were analyzed retrospectively. We utilized cyclophosphamide, vincristine, adriamycin, and methotrexate (CVAM) for OPD-based adjuvant chemotherapy. From 1990, primary chemotherapy was administered to patients with intraocular disease for eyeball-saving and patients received a combination of etoposide, vincristine, cisplatin (or ifosfamide) as a moderately intensive regimen, or a combination of cisplatin, doxorubicin, etoposide, and cycophosphamide (CDEC) as a highly intensive regimen. RESULTS: One hundred eighteen children were analyzed. There were 68 unilateral and 50 bilateral diseases. The median age at diagnosis was 1 year and ReeseEllsworth stage V was the most common stage at the time of diagnosis. All patients were treated by chemotherapy-based multimodality methods, and primary chemotherapy was administered to 80 patients. The 10-year overall and event-free survival rate of all patients were 93.9% and 91.6%, respectively. Two patients who died were in the CDEC regimen group, but there was no significant statistical difference in survival rates by chemotherapy regimens. Fifty-six of 114 eyeballs were saved after primary chemotherapy-based treatment, and the eyeball-saving rate was 49.1%. Six patients relapsed after enucleation and 2 patients were treated successfully after autologous PBSCT. Osteosarcoma occurred in 2 patients as a secondary malignancy, and facial asymmetry after radiotherapy was the most common long-term sequelae. CONCLUSIONS: In this study, the overall and event-free survival rates of retinoblastoma were satisfactory and eye-saving was possible with primary chemotherapy. Development of new chemotherapeutic regimens and a team approach are necessary to improve the eyeball-saving rate.

Efeitos do dietilditiocarbamato em trofozoitos de giardia lamblia: uma nova ferramenta na terapia contra a giardíase / Effects of dietilditiocarbamto in trofozoitos of giardia lamblia: a new tool in therapy against giardiase

O protozoário microaerófilo Giardia lamblia coloniza o trato intestinal de hospedeiros vertebrados, onde é exposto a diferentes concentrações de oxigênio. Apesar do metabolismo fermentativo, trofozoítos de Giardia consomem oxigênio e mecanismos de detoxificação são requeridos. Desprovido de glutationa, Giardia expressa altas concentrações de proteínas ricas em cisteína (CRP, também conhecidas como proteínas variantes de superfície ou VSP), como defesa antioxidante. Este mecanismo envolve ciclagem redox para a manutenção de um ambiente intracelular reduzido e proteção contra o estresse oxidativo. Neste contexto, substâncias que interfiram na resposta antioxidante deste protozoário podem compreender uma poderosa estratégia quimioterápica contra a giardíase. Neste estudo, nós analisamos os efeitos do dietilditiocarbamato (DETC), um inibidor de superóxido dismutase (SOD), na proliferação do parasito, expressão de tióis totais, lipoperoxidação, produção de radicais livres e arquitetura celular. DETC inibiu a proliferação celular em níveis semelhantes ao metronidazol e induziu a peroxidação de membranas neste parasito, possivelmente pelo aumento de espécies reativas. Alterações ultraestruturais também foram observadas neste protozoário. Células tratadas com DETC apresentaram alto grau de extração citoplasmática, além de estruturas indicativas de autofagia. As vesículas periféricas também se encontravam maiores, sugerindo confluência. Estes efeitos são independentes de SOD, já que Giardia não apresenta esta enzima. Detecção de grupos tiol com a sonda fluorescente o-phthaldialdeído (OPA) foram significantemente moduladas negativamente pelo DETC. Estes dados nos indicam que DETC aumenta o estresse oxidativo em trofozoítos de Gardia lamblia pela reação com grupos tiol.

The microaerophilic protozoan Giardia lamblia inhabits the upper small intestine mucosa of vertebrate hosts, where it is exposed to different concentrations of oxygen. Despite the fermentative metabolism, Giardia trophozoites consume O2 and produce oxygen free radicals and therefore mechanism for detoxification are required. Devoid of glutathione, Giardia express highconcentrations of cystein-rich proteins (CRP, also known as variable surface protein or VSP), as an antioxidant defense. This mechanism involves redox cycling for maintenance of a reducedintracellular environment and protection from oxidative stress. In this regard, substances that interfere in the antioxidant response of this protozoan could comprise a powerful chemotherapeutic strategy for Giardia lamblia infection. Here, we analyzed the effects of DETC, a superoxide dismutase (SOD) inhibitor, on parasite proliferation, thiol expression, lipid peroxidation, free radicals detection and cell architecture. DETC inhibited parasite proliferationat levels similar to metronidazole and induced peroxidation of membrane, possibly by the increase of reactive species.Ultrastructural alteration were also observed. Since this protozoan isdevoid of SOD, here present data indicate SOD-independ DETC effects. Thiol groups detection with the fluorescent probe o-phthaldialdehyde (OPA). Cells treated with DETC displayed washed out cytoplasm and structures indicative of autophagy. The peripheral vesicles also had an increased volume, presumably caused by homophilic fusion. Taken together these data indicate that DETC enhance the oxidative stress in Giardia trophozoites by reacting with thiol groups.

Inhibition of selenium dependent glutathione peroxidase and superoxide dismutase in rats by diethyldithiocarbamate: effect of pre-administration of alpha-tocopherol.

Rats pre-administered with alpha-tocopherol (10 mgs/day) for 7 days afforded a significant protection at the tissue level against the lowering of superoxide dismutase and glutathione peroxidase, especially the selenium-dependent glutathione peroxidase. The protective action of alpha-tocopherol in the diethyldithiocarbamate treated rats may be attributed to its antioxidant/free radical scavenging action. It is concluded that selenium-dependent glutathione peroxidase and alpha-tocopherol act in a complementary fashion to block free radical formation.

Efeito do dietilditiocarbamato de sódio (DETC) na susceptibilidade da cândida albicans à anfotericina B: em busca do sinergismo / Effect of diethyldithiocarbamate sodium (DETC) in the susceptibility of candida albicans to amphotericin B: in search of synergism

Candida albicans, fungo cosmopolita, é considerado um comensal comum da microbiota de pessoas saudáveis. No entanto, com o avanço da AIDS e outras condições que comprometem o sistema imunológico, como o tratamento de neoplasias dentre outros, fizeram com que as infecções fúngicas aumentassem 400 por cento nas últimas duas décadas (Beck-Sangue et al., 1993; Pfaller, 1994; Jarvis et al., 1995). A superóxido dismutase (SOD), fator de virulência em C. albicans, é requerida na detoxificação do superóxido. Sendo o dietilditiocarbamato de sódio (DETC) um potente inibidor da SOD, avaliamos no presente estudo o seu efeito fungicida na proliferação in vitro da Candida albicans, sozinho e em combinação com a anfotericina B. O DETC demonstrou um efeito dose-dependente e inibição significativa da proliferação com apenas 6hs de cultivo. A sua combinação com a anfotericina apresentou um efeito sinérgico com FIC = 0,8. Com o objetivo de avaliar as alterações ultraestiuturais induzidas pelo DETC, as leveduras foram tratadas ou não por 24 horas e então processadas para microscopia eletrônica de transmissão. A ultraestrutura de leveduras tratadas com 100l-tM ou 150l-tM de DETC apresentaram extração quase completa do citoplasma e componentes intracelulares. Além disso, foram observados múltiplos corpos vesiculares, contendo matéria de natureza diversa e figuras de mielina. Nossos dados sugerem indução de processo autofágico porém, novos experimentos com abordagem citoquímica serão realizados para confirmação dos resultados.

Influences of DTC and zinc supplementation on the cellular response restoration in restrained mice

The studies were conducted on Balb/c mice exposed to restraint stress twice for 12 h at 24 h intervals. Prior to restraint stress the mice were treated with sodium diethyldithiocarbamate (DTC) i.p. at a dose of 20 mg/kg five times at 48 h intervals. DTC was used per se or with zinc ions interaction, by adding zinc sulfate to drinking water at a dose of 72 microgram/mouse daily. The results obtained in the study show that restraint stress causes involution of lymphatic organs, decreased the percentage of immature (CD4+CD8+) and, mature (CD4+) thymocytes and CD4+, CD8+and CD19 + splenocytes and proliferative response of thymocytes stimulated in vitro with concanavalin A (Con A) and phytohemagglutinin (PHA). The restraint stress decreased also interleukin-1 (IL-1) production by murine intraperitoneal macrophages stimulated in vitro with lipopolysaccharide (LPS) from E. coli. Pretreatment with DTC counteracted restraint stress-induced immunosuppression, which is expressed as partial normalisation of the total number of thymocytes, splenocytes and IL-1 production, accelerated regeneration of thymus and spleen, shorter suppressive action of restraint stress on the percentage of CD4+CD8+thymocytes and in total normalisation of the CD4+thymocytes and splenocytes. DTC administered prior to restraint stress augmented the proliferative response of thymocytes to two mitogens. The immunocorrecting action of DTC is enhanced by zinc supplementation, expressed in the increased percentage of CD4+thymocytes and splenocytes, CD19 + splenocytes, proliferative activity of thymocytes stimulated with PHA and IL-1 production. The obtained results show that DTC administration can be supplemented with zinc in order to restore the immune system impaired by stress.

Protective role of diethyldithiocarbamate against toxicity of some new antibacterial and antitumor platinum[II] and [IV] organochelates

Aim: Five newly synthesized Schiff base complexes of the platinum [II] and [IV] were screened for their in vitro antibacterial and antitumor activity. Meanwhile, the protective role displayable by diethyldithiocarbamate [DDTC] against the inducible toxicity of two of platinum chelates was investigated as well. Their minimal inhibitory concentrations [MICs] were determined against narrow range of Gram negative and Gram positive bacteria while the antitumor potentials were tested against Ehrlich ascites carcinoma [EAC]. Half LD50 of the two selected antitumor complexes [naphthylaldehyde and diamino hexane [Pt [II] NDAH] and Pt [IV] NEDA] was i.p. injected in male Sprague Dawley rats then their biochemical consequences were investigated. The mode of action studies on intact cells of the most sensitive bacterium [Bacillus subtilis NRRL-B-4378] revealed that Schiff base Pt[IV] chelate derived from naphthylaldehyde and ethylene diamine [Pt [IV] NEDA] had reasonable reducing effects on microbial RNA and protein contents, while DNA was powerfully affected. Regarding their toxicity, Pt[IV] NEDA was found to be less hepato and nephro toxic than Pt[Il] NDAH. The hepatotoxic and nephrotoxic effects of these two platinum complexes seem to be reasonably ameliorated in animals post treated with DDTC as indicated by nearly restoration of normal values of the studied biochemical parameters

In vivo inhibition of selenium dependent glutathione peroxidase and superoxide dismutase in rats by diethyldithiocarbamate.

Intraperitoneal injection of rats with diethyldithiocarbamate (1.2 g/kg body wt) led to maximum diminution of superoxide dismutase activity at 1 hr by 86 and 84% in liver and red blood cell respectively with a gradual return to the normal level at 48 hr after administration of injection. Significant inhibition of selenium-dependent glutathione peroxidase was also observed, which returned to normal at 48 hr after administration of injection. However, maximum decline in its activity was at 12 hr by 52 and 73% in liver and red blood cells respectively. No significant difference in tissue level of selenium-independent glutathione peroxidase was observed during time course study after diethyldithiocarbamate administration. It is possible that inhibition of superoxide dismutase by diethyldithiocarbamate leads to accumulation of superoxide anion which in turn inactivates selenium-dependent glutathione peroxidase by its reaction with selenium at the active site of the enzyme.

Evaluation of the Cytotoxicity of Polyetherurethane (PU) Film Containing Zinc Diethyldithiocarbamate (ZDEC) on Various Cell Lines

A polyetherurethane (PU) film containing 0.1% zinc diethyldithiocarbamate (ZDEC) is the international standard reference material for testing the in vitro cytotoxicity of polymer based biomaterials. Nowadays, culturing L929 or BALB/3T3 cells in direct contact or in an extract dilution condition is the most frequently using method for evaluating the cytotoxicity from biomaterials and medical devices. However, the results often vary, because it is directly related to the cellular functions and the mechanism of the toxicity of the contacting cells. In this study, 13 cell lines originating from various tissues were used to detect the cytotoxic activities of a PU film containing 0.1% ZDEC (PU-ZDEC). The correlation between the reactivity zone size and the relative cytotoxicity by quantifying the released total protein from each cell in the direct contact testing method was investigated. Hepa-1c1c7 cells demonstrated the highest sensitivity in the reactivity zone size, while CHO/dhFr(-) cells were the most sensitive in terms of the relative cytotoxicity. A correlation between the two processes in each cell line was not found (r=-0.478). In the extract dilution method, which involved cultivating the cells in the medium with various ZDEC concentrations prepared by diluting the PU incubation, the cytotoxicity increased with increasing ZDEC concentration in all cell lines. The BALB/ 3T3 cells demonstrated the highest sensitivity in the extract dilution method. No correlation in a comparison of the relative cytotoxicity from the direct contact method with the extract dilution method in each cell line, was found (r=-0.445). In this experiment, Hepa-1c1c7, BALB/3T3, CHO/dhFr(-) and L-929 cells among the 13 types of cell lines were the sensitive cell lines according to the two methods. The preliminary results suggest that a comparison of at least one or more cytotoxicity testing methods and many cell lines is necessary for an in vitro cytotoxicity test of biomaterials.

The Effects of Diethyldithiocarbamate on the Metabolism and Hepatotoxicity of Trichloroethylene / 대한산업의학회지

OBJECTIVES: The purpose of this study was to evaluate the trichloroethylene (TCE) metabolism, acute toxicity, and the effects of diethyldithiocarbamate (DDTC) on the acute toxicity in TCE-intoxicated rats. METHODS: TCE was administered orally at doses of 600, 1,200 and 2,400 mg/kg of body weight following pretreatment with either saline or 500 mg/kg of DDTC. 12 hours after administration of TCE, the concentrations of TCE, trichloroacetic acid (TCA) and trichloroethanol (TCEOH) in the blood and solid organs, and the histopathological changes in each organ were examined. RESULTS: The level of CYP2E1 markedly decreased in the DDTC-pretreated groups. The CYP2E1 content in the TCE-treated rats increased in a dose-dependent manner. The concentrations of TCE and TCEOH were highest in the liver, and the level of TCA was highest in the blood. The DDTC-pretreated rats had a markedly increased level of TCE and decreased levels of TCA and TCEOH, than the rats pretreated with saline. These findings indicated that CYP2E1 was important in the metabolism of TCE. From the histopathological findings, centrilobular necrosis was observed in the livers of the TCE-treated rats, but no significant change was found in those rats pretreated with DDTC. CONCLUSIONS: DDTC is considered to be effective in protecting TCE-induced hepatic damage because it inhibits the TCE metabolism.

Hypotension Caused by a Disulfiram-Alcohol Reaction

Disulfiram, or antabuse, is used in the treatment of chronic alcoholism since it causes an unpleasant aversive reaction to alcohol. It works by inactivating hepatic aldehyde dehydrogenase, leading to a pronounced rise in the acetaldehyde concentration when ethanol is metabolized. Acetaldehyde causes alcohol sensitivity, which involves vasodilation associated with increased skin temperature, subjective feelings of hotness and facial flushing, increased heart and respiration rates, lowered blood pressure, a drymouth or throat sensation associated with bronchoconstriction and allergy reactions, nausea, and headache. One of its metabolites, diethyldithiocarbamate (DDC) can inhibit the enzyme dopamine beta-hydroxylase (DBH) through copper chelation. This may account for the profound refractory hypotension seen with the disulfiram-ethanol reaction (DAR), resulting from norepinephrine depletion. This report is presents the case of a patient we met, who presented with severe hypotension caused by the disulfiram-alcohol reaction, and along with a brief review of the subject.

The Harmful Effects of Superoxide Radical and the Protective Effect of Ginseng Saponin on Rat Whole Bladder Contractility / 대한비뇨기과학회지

PURPOSE: We investigated the effects of the superoxide radical on rat whole bladder contractility with duroquinone (superoxide radical generator, Dq) and diethyldithiocarbamate (superoxide dismutase inhibitor, DETCA), and the effects of ginseng saponin (GS) against superoxide radical injury. MATERIALS AND METHODS: Isometric tension changes of isolated rat whole bladders were recorded in an organ bath using a force transducer. The acute effects of Dq and Dq preincubated with DETCA were assessed on resting tension, electrical field stimulation, and bethanechol-, ATP-, and KCl-induced contraction. The effects of Dq and Dq preincubated with DETCA in the presence of sodium nitroprusside and GS were investigated. RESULTS: The resting tension of the muscle was not changed by Dq and Dq preincubated with DETCA. Dq had a harmful effect on only ATP- and KCl-induced detrusor contraction, whereas Dq pretreated with DETCA attenuated the induction of detrusor contraction which was reduced in response to the exogenous NO including GS. In the presence of L-NAME, the effects of GS reduced the Dq-induced inhibition on the detrusor contractility. CONCLUSIONS: It is suggested that the superoxide radical may be the cause of voiding difficulty. GS, as a NO synthesis stimulator, seems to act as a scavenger of the superoxide anion. However further study on the effect of each subfraction of GS is needed for clinical application.

Acute Effects of Superoxides on the Relaxation of Rabbit Corporal Smooth Muscles / 대한남성과학회지

PURPOSE: In an aerobic environment, all biological organisms react with reactive oxygen specise, especially O2 free radicals and hydrogen peroxide. Although acute disorders do not appear, continuous increases of it can lead to aging or cancer. In this study, the acute effects of duroquinone (2,3,5,6-tetramethyl-1,4-benzoquinone, DQ, superoxide radical generator) on corporal smooth muscle was investigated, which causes flavorprotein to produce superoxide via chemical reduction reaction. MATERIAL AND METHOD: Under the same conditions, corporal smooth muscle strips were acquired from 2.0-2.5 kg Male New Zealand White rabbit. Then strips were placed in tension measuring apparatus. After strip was contracted by phenylephrine, an electric field stimulation (EFS)- and various drugs-induced relaxation rate was measured. Relaxation rates by above-mentioned methods were measured again following incubation of DQ or DQ and diethyldithiocarbamate (DETCA, superoxide dismutase inhibitor). The tension percentages were calculated with respect to the control group. RESULTS: The resting tension of the muscle strip was not changed by applying of DQ (0.01, 0.1 and 1 mM). The relaxation rates by EFS and bethanechol were not attenuated after DQ was incubated, but attenuated after DQ and DETCA were incubated. The relaxation rate by ATP was not attenuated after DQ, or DQ and DETCA was incubated. The relaxation rates by sodium nitroprusside was attenuated after DQ only was incubated. CONCLUSIONS: Superoxide seems to eliminate nitric oxide, and thus be an important corporal smooth muscle relaxation inhibitor.

Evaluación química y biológica del ditiocarbamato 43GV040 durante sus estudios preclínicos: estudios de estabilidad / Chemical and biological evaluation of dithiocarbamate 43GV040 during pre-clinical tests: stability studies

El ditiocarbamato 43GV040 presenta manifestaciones neurotóxicas cuando se administra en dosis letales a ratones, ratas y perros, por lo que se propuso hallar una evaluación biológica que indicara el comportamiento de esta toxicidad, así como disponer de una evaluación que corroborara la integridad del producto durante sus estudios preclínicos. En este estudio se demostró que existe una correspondencia entre las determinaciones biológicas y químicas propuestas; pudiéndose anunciar que tanto la materia prima como las formas farmacéuticas, se encuentran aptas en sus parámetros de calidad, cuando realizado el ensayo bajo las condiciones expuestas, el grado de neurotoxicidad se encuentra entre 40 y 50 transcurridos 45 min de la administración del producto. Se presentan datos sobre la estabilidad del producto almacenado en diferentes condiciones hasta el año de elaborado