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Alkaloids with aporphin skeleton from Stephania dielsiana Y. C. Wu of Vietnam

From the tube of Stephania dielsiana (Menispermaceae) collected in Hoa Binh province three alkaloids dehydrostesakine, 1,2-methylendioxy-8,9-dimethoxy-7-oxodibenzoquinoline and 1,2- methylendioxy-8-methoxy-7-oxodibenzoquinoline have been isolated and characterized by spectroscopic analyses (mainly by 1 D and 2D NMR). The 1,2-methylendioxy-8-methoxy-7-oxodibenzoquinoline is a new compound.

Contribution to the standardization of dry extract of Asiatic pennywort herb-turmeric

To support the development of national standards and to ensure the quality of dried extracts of Centella asiatica and Curcuma longa, the study provided quality specifications as follows: appearance, loss on drying, the solubility in water and in alcohol, the water-insoluble teside, heavy metals limit, pH, ash, fungus, mould, and microbial limit; phosphorus pesticide residues, qualitative and quantitative determination of triterpene ester glycosides and curcuminoids.

Contribution to the study on process of lipid peroxydation in cellular membran and modifications of some anti-oxidant enzymes during the storage process of erythrocytes

Study on the peroxidation of membrane lipid and the change of some anti-oxidant enzymes during the storage of erythrocytes by additive system. The in vitro study was conducted with two additive systems: one is the “AS- T” which is the first preparation in Vietnam and the other is the preparation of Terumo, a leading company of the world on the blood preparations. The results demonstrate that the two systems are equally in the anti-peroxidation activation of membrane lipid. The ability to maintain enzyme activation of Superoxyd dismutase (SOD) and Glutathion peroxidase (GSH-Px) of erythrocytes during of storage process (from 0 to 35 days), the erythrocyte mass which is preserved by “AS-T” solution abilize activity of SOD and GSH-Px better than by Terumo solution, with this result os significant slower increasing of MDA concentration at the end of storage.

Contribution to the study on some biological effects and cytotoxic possibilities of substances isolated from Croton tonkinensis Gagnep. in Vietnam

The bioassay guided chemical fractionation has showed that: the ent-kauran diterpen may be a promising leading structure for new derivatives of high bioactivity. The following research work is still in progress to obtain the last conclusions.

Dosage of vitamines B1, B2, B6, PP in the injectable product becozyme by capillary electrophoresis method

A capillary electrophoresis method was used for simultaneous detetmination of vitamines: B1, B2, B6 and PP in multivitamines injection (Becozym-Roche). The method was simple, rapid, economic, accurate and in high precision. Relative errors were from 0.65% to 1.53% and recoveries were from 99.7% to 101.4%.

Investigation and evaluation of the task to manage the safe rational and effective use of antibiotics in the Central Hospital of Gynecology and Obstetrics

The result of initial investigation and evaluation shows the National Hospital of Obstetrical Gynecological have had fixed successes in using and managing antibiotics use. With safety, suitability and efficiency in antibiotic use, it has important contributed to raise efficiency and significantly reduce treatment cost. In addition, it has reduced antibiotic resistance ratio.

Investigation on elimination of two optic isomers of chlorpheniramine in urine on experiments in man

Chlorpheniramine (CPAM) is a chiral antihistaminic drug commercialized as a racemic mixture. The pharmacokinetic of chlorpheniramine (elimination) of the formulation of racemic chlorpheniramine combined with phenylpropanolamine, was assessed in an open-labelled, randomized, after administration of 8mg of racemic chlorpheniramine in 18 healthy Vietnamese subjects (9 men and 9 women). The 18 subjects received Contac after an overnight fast. Urine samples were collected up to 144 hours. Urine concentrations of individual enantiomers of chlorpheniramine were determined with a validated chiral HPLC method. Elimination of unchanged CPAM in urine was not stereoselective and no difference was observed for male and female subjects.

Investigation on solubility of two products of chlorpheniramine with release action

Chlorpheniramine (chlorphenamine) is a racemic antiallergic antihistaminic H1 drug presenting 2 enantiomers. The bioequivalence of two sustainedreleased formulations (reference and Vietnamese tested formulation) of racemic chlorpheniramine combined with phenylpropanolamine, was assessed firstly, in a dissolution test in vitro according to USP requirements. The present work compares in vitro dissolution rates of two formulations of chlorpheniramine maleate. The two formulations are equivalent in vitro, both in a water medium or in a SGF/SIF medium. The pH is not a critical parameter affecting drug release and allows to use purified water for chlorpheniramine dissolution test.

Polyphenolic component of fruit skin of Garcinia mangostana L. and inhibitory effect on acid production by Streptococcus mutans GS-5

Using thin layer chromatogrphy and a solvent system containing toluen:ethyl acetate:aceton:formic acid (TEAF) with ratio 5:3:1:1 we isolated 15 bands of flavonoids from the peel of mangosteen (Garcinia mangostana L.). The bands showed the specific colours and specific UV spectrum for carbon skeleton of flavonoid compounds. The bands corresponding with Rf 0.68; Rf 0.77; Rf 0.80; Rf. 0.86; Rf 0.91 had stronger colour compared to the other bands. Only the band with Rf 0.42 could excite under the UV rays. Three bands corresponding to Rf 0.80; Rf 0.86 and Rf 0.91 exhibited strongly the inhibition activity of acid production by Streptococcus mutans GS-5 in excess glucose media. The final pH value of Streptococcus mutans GS-5 suspension for these bands were 4.5, 5.2 and 6.2, respectively, compared to 3.9 of the control. The obtained results suggest that inhibition activity of acid production by Streptococcus mutans GS-5 of MC extract seems to relate to these three bands. Their structure and action mechanism are under examination.

Preliminary evaluation of the real situation of pharmacists graduated in Pharmacy College during their activities in the Delta of Mekong River

The result of this study showed that 92% pharmacist who are working at provincial level &8% pharmacist doing at districts level. 54 districts-about 58% those of the Mekong Delta-have no pharmacist. Speciality level of pharmacists is rather good but their foreign language is not good, only 2% pharmacists who either had level C or could use foreign language fluently. 61.9% pharmacist have needed to be retrained mainly subjects such as pharmaceutical administration, clinical pharmacy and 64.5% to be trained at post graduate level, with two mainly types: speiciality and master courses. Training pharmaceutical man power Facilities should increase opening retraining courses. Using pharmaceutical man power Facilities should assign tasks more to use pharmaceutical man power suitable.

Qualitative evaluation of some imported drugs before and after their sending by Incorterm 2000

The major reason of this research was to identify the lead time of drugs that delivered by the airway or shipment, and to compare pharmaceutical drug quality within delivering time. This analytical cohort study included 124 lots of combined tablets of Ethambutol/Isoniazide 400/150mg, Rifampicine/Isoniazide 150/100mg and Pyrazinamide 500mg delivered from India to Vietnam during April 2001 to September 2003. Because of selection bias, 124 lots were randomly selected at Vietnam ports, 25 in Noi Bai and Tan Son Nhat airport and 99 in Hai Phong and Sai Gon port. Results showed that, delivery time was approximately 9 days in airway and estimated time of 32 days in shipment. The time for issuing Vinacontrol's certificate on drug quality was approx. 35 days. The results of testing drug quality before and after delivering pharmaceuticals from India to Vietnam found that testing indicators excepted assays were as same in certificate of manufacturer, SGS International and Vinacontrol and assay of imported drugs was in rank of registered standards. The findings suggest that time for issuing certificate on drug quality is longer than delivering time both the airways and the shipment. It is recommended that management of lead time is more efficiency if the time for issuing Vinacontrol's certificate is reduced. This study can be used as a guidance to determine pharmacoeconomics of managing drug delivery.

Restorative effects of Radix Notoginseng on hepatic lesions provoked by CCl4 in experimental mice

The experimental results showed that the oral administration of Radix Notoginseng (RD) with the dose of 5g/kg body weight exhibited the moderate recovering effect on CCl4-induced liver injuries in rats. Although the serum ASAT concentration in CCl4-intoxicated and RD-treated group was still higher than that of control-normal group after one day, it was significantly lower than that of intoxicated and non treated group (p<0.01). There were no differences in ALAT concentration between RD-and CCl4-treated groups in that day. The four days treatment with Radix Notoginseng has reduced the concentrations of both ASAT and ALAT to normal levels while ASAT in CCl4-intoxicated rats was still higher.

Standardization of erythromycine gel product

In this study, gel erythromycin, which has been used in treatment of acne, was standardized on appearance, viscosity, pH, parliculate matter, weight uniformity, identification, and assay. Additionally, quantitative determination of erythromycin in the finished-product was carried out by using microbiological method.

Study on adenine influence on erythrocyte number, pH and osmotic pression of erythrocyte volume during the process of conservation

Study on the effect of adenin on the number of red blood cell, pH and osmotic pressure of erythrocytes showed that the presence of adenin in the content of additive system strongly affect on the ability to maintain the RBG, to stabilize the pH and osmotic pressure of erythrocytes. The effect was propotional to adenin concentration and the most suitable concentration was 0.04g/100ml.

Study on application of spreading cellules to investigate on skin absorption possibility of drug from TTS-nitroglycerin

The modified Franz diffusion cell was used to evaluate the permeation of nitroglycerin through snake, pork-ear and rabbbit isolated skins. The temperature is altered at 25°C, 37°C and then 41°C. Skins, which are used for experiment, are from snack, pork-ear or rabbit. Each cm2 of skin receives 2,856 mg of nitroglycerin. Nitroglycerin concentrations in the samples were assayed by high-performance liquid chromatography (HPLC). The results showed that the higher temperature, the more nitroglycerin is permeated; the snake skin permeation ability is the lowest and the rabbit skin is the highest.

Study on chemical compositions of essential oil extracted from leaves of Blumea balsamifera (L.) DC. in Vietnam

The essential oils obtained from the leaves of Blumea balsamifera DC. harvested in three provinces of Vietnam (Ha Giang, Hanoi and Dak Lak) were analyzed using GC-MS. The major components of the oils were: borneol 57.82%, beta-caryophyllene 8.27%, denta-cadinol 7.95%, and caryophyllene oxid 3.10% (oil of B. balsamifera harvested in Ha Giang); borneol 50.57%, camphor 18.71%, beta-caryophyllene 10.06%, denta-cadinol 3.14%, patchoulene 2.99%, and veridiflorol 2.01% (oil of B. balsamifera harvested in Hanoi); camphor 70.05%, beta-caryophyllene 10.54%, borneol 5.70% and carvacrol 5.70% (oil of B. balsamifera harvested in Dak Lak).

Study on chemical domain and biological properties of the receip of Chinese angelica in M decoetion

The chemical composition of remedy has been investigated. The study results showed that the remedy contained flavonoid, saponosids, fat, sugar and 20 amino acids. Alcohol extract 2: 1 of remedy increased the body weight by 20%, heat withstanding at 400C by 25.23%, and forced wimming by time 345.45%, p<0.05 in mice.

Study on extraction isolation, identification of biological effects and content of steroid hormon on some echinoderms of Vietnam

In this article we reported about extraction of steroid hormones (testosterone, estradiol, progesterone) from eggs of sea urchin (Tripneustes gratilla, Astropyga radiata) and sea star (Stellaster sp., Echinaster luzonicus), from pyloric coaca of sea star and from meat of sea cucumber (Bohadschia argus Jaeger). After extraction of this hormones we determined their levels in this tissues. The results are followed: - The yield of extraction with methylen chlorid and methanol is many times higher than with ethanol and ether ethylic. - Extracts from egg of sea star and sea urchin were proved to have activity of estrogene, progesterone and testosterone. - The levels of testosterone, estradiol and progesterone in the pyloric ceaca of sea star are higher than in their eggs.

Study on hypoglycemiant effect of Sambucus nigra ssp. canadensis (L.) R. Bolli

In the present study, we investigated the effect of extract from Sambucus nigra ssp. canadensis (L.) R. Bolli flowers on streptozotocin-induced diabetic mice. A single daily dose of the extract (equivalent to 0.4g flower/kg daily) were administered for 5 days or 10 days to the diabetic mice immediately following Streptozotocin injection. As a result, extract from Sambucus nigra ssp. canadensis (L.) R. Bolli flowers inhibited glucose concentration in diabetic mice at the investigated dose. It is indicated that the flowers of Sambucus nigra ssp. canadensis (L.) R. Bolli may be an effective agent for treatment of diabetes.

Study on influence of artesunate on the reproductive process in white mice

In order to find the artesunat affect on reproductive progress of parents P. generation mice F1 , F2. The result showed that: Artesunat at doses of 50mg/kg the first day and 25mg/kg per day for four following days had no effect to the birth progress of P, F1 and F2: Concretely: - No coffuse birth: ratio of conjugation, conception, early died feotus and late died feotus among P, F1 and F2 were similar. - No innate defects in born mice from P, F1 and F2. Quantity and weight of mice were in normal.

Study on manufacture of indomethacin Pellet LR by method of strenghthening gradually

Sustained release pellets containing indomethacin were prepared by layering method in conventionel coating pan. In the pellets, Avicel has been used as a spheronized excipient. The solution of PVP 5% lethanol was found to be an indomethacin solubility enhancer. After coating with EC, pellets showed an in vitro drug release model for 12h. Coated pellets may be filled into the capsules shell to prepare sustained release dosage form.

Study on the role of aryl-hydrocarbone-receptor (AhR) in the induction CYP1A1 by serum

CYP1 A1 is an isoform of cytochromes P450. This isozym plays an imfortant role in the initiation of cancer because it actives many procarcinogens. Generally, CYP1A1 gen is not expressed consticutively in liver, but in extrahepatic tissus. In presence of inducers, CYP1A1 gen is induced potentially in both liver and extrahepatic tissus. The cancer's risk is increased by CYP1A1 overexpression. The CYP1A1 induction is mainly regulated via AhR pathway, in which the receptor Ah plays a pivot role. We have previously demonstrated that humain or foetal bovine serum induced CYP1A1. This induction is possibly passed other pathway. In present study, we demonstrated by using RTPCR, gen reporter and Western blot that AhR is necessary for CYP1A1 induction by serum but not sufficient.