Recursos de colección

Universidad Nacional de La Plata (75.269 recursos)

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vol. 31, no. 04

Mostrando recursos 1 - 20 de 23

  1. Comparative study and anticholinesterasic evaluation of essential oils from leaves, stems and flowers of myrciaria floribunda (H.West ex Willd.) O. Berg

    Tietbohl, Luis A. C.; Lima, Barbara G.; Fernandes, Caio P.; Santos, Marcelo G.; Silva, Fabiana E. B. da; Denardin, Elton L. G.; Bachinski, Róber; Alves, Gutemberg G.; Silva Filho, Moacélio V.; Rocha, Leandro
    Myrciaria floribunda (H.West ex Willd.) O.Berg, Myrtaceae, popularly known as “camboim amarelo”, was collected in Restinga de Jurubatiba (RJ, Brazil). Leaves, stems and flowers were individually submitted to hydrodistillation, affording the respective essential oils. Monoterpenes were the main group of essential oils from leaves (53.9 %) and flowers (55.4 %). Sesquiterpenes were more representative in stems (72.2 %). 1,8-cineole was the major constituent in the essential oil from leaves (38.4 %) and flowers (22.8 %). The major constituent from stems was (2E,6E)-farnesyl acetate (19.9 %). To our knowledge, these are the first contributions for essential oils from stems and flowers...

  2. Solubility of losartan potassium in several mono-solvents at different temperatures

    Eghrary, Shadi H.; Zarghami, Reza; Jouyban, Abolghasem
    The solubilities of losartan potassium in eight solvents; 1,4-dioxane, acetonitrile, propylene glycol, N-methyl-2-pyrrolidone, 1-butanol, 1-hexanol, 1-heptanol, and 1-octanol, were measured at temperatures ranging from 293.2 to 318.2 K at atmospheric pressure using shake-flask method of Higuchi and Connors. N-methyl-2-pyrrolidone dissolved the highest amount of losartan potassium and 1,4-dioxane possessed the lowest solubilization power among the investigated solvents. The generated data was used to calculate the thermodynamic parameters of the system using the modified van’t Hoff equation and the Gibbs free energy data was correlated using Abraham solvation parameters.

  3. 20(S)-Protopanaxatriol (Ppt) Exhibits Inhibition Towards UDPGlucuronosyltransferase (UGT)-Catalyzed Zidovudine Glucuronidation

    Xing, Jin; Che, Wen
    Drug-drug interaction (DDI) is a challenging problem for treatment of HIV-infected patients. Zidovudine (AZT), prescribed under the names Retrovir and Retrovis, is the first U.S. government-approved antiretroviral drug used for the successful treatment of HIV/AIDS infectiousness. Given that ginseng is frequently utilized in combination with AZT and AZT is mainly eliminated by UDP-glucuronosyltransferase 2B7, the aim of present study is to investigate the inhibition of UGT2B7-catalyzed AZT glucuronidation by 20(S)-protopanaxatriol type (Ppt) which is the main ginsenoside absorbed into the plasma. The results showed that ppt competitively inhibited UGT2B7-catalyzed AZT glucuronidation, and the inhibition kinetic parameter (Ki ) was determined to...

  4. Tacrolimus (Tacro) strongly inhibits intestinal UDP-glucuronosyltransferase (UGT) 1A8

    Yu, Jian; Wang, Chuan-Qiang; Fang, Long-Hao; Li, Meng; Wang, Xiangyang; Dai, Lu-Lu; Gao, Ya-Jie
    Tacrolimus (Brand name: Prograf), a kind of immunosuppressants, has been reported to induce drug-drug interaction with many clinical drugs. Tacrolimus-mycophenolic acid (MPA) interaction has been widely and frequently reported. Intestinal UDP-glucuronosyltransferase (UGT) 1A8-mediated metabolism plays a key role in the elimination of MPA, and alteration of the activity of UGT1A8 resulting from gene polymorphisms could significantly influence the catalyzing activity of MPA glucuronidation. The aim of the present study is to investigate the inhibitory potential of tacrolimus towards UGT1A8, which was speculated to be a potential cause for tacrolimus-MPA interaction. The recombinant UGT1A8 was used as enzyme source, and a...

  5. Platinum and palladium complexes with 2,4-Dinitrophenylhydrazine: synthesis and cytotoxic activity

    Souza, Gustavo D. de; Fernandes, Lucianno E.; Rodrigues, Mônica A.; Silva, Priscila P.; Pereira-Maia, Elene C.; Guerra, Wendell
    New complexes of platinum and palladium were isolated with 2,4-dinitrophenylhydrazine (2,4-DNPH). These complexes were characterized and the results shown that the ligand is coordinated to platinum or palladium by the basic nitrogen of NH2 group and have the general structure cis-[M(2,4- DNPH)2Cl2 ].H2O where M = Pt or Pd. The thermal stability of the complexes was followed in the temperature range 25-850 ºC. The antitumor activity of the synthesized compounds has been studied and the compound cis-[Pt(2,4-DNPH)2Cl2 ], was found to display cytotoxicity (IC50 = 4.6 μmol/L) against K562 tumoral cell line. This work is the first to describe the...

  6. The effects of (+)-Gossypol on 11β-HSD and the concentration of corticosterone and dehydrocorticosterone in mice serum and tissues

    Qiu, Xiangjun; Li, Wanshu; Li, Junwei; Wang, Mengmeng; Wang, Jia; Chen, Lianguo; Sun, Wei; Zhang, Likang; Wen, Congcong; Ge, Renshan; Hu, Guoxin
    11β-hydroxysteroid dehydrogenase (11β-HSD) plays an important part in mediating glucocorticoid action, catalyzing the interconversion of corticosterone (B) and dehydrocorticosterone (A) in rodents. The aim of our study is to investigate the effects of (+)-gossypol (G+) on 11β-HSD. Adult ICR mice were given B and B + (G+) by intraperitoneal injection. The activity of 11β-HSD was evaluated by measuring the ratio of A and B, meanwhile the effects of (+)-gossypol on the conversion rate of B to A was determined with HPLC. Serum A/B levels of the B+(G+) group decreased by 2.42, 7.32, 17.85, 31.39, and 40.02 % compared to the...

  7. Use of response surface methodology to optimize chitosan microparticles for sustained release of curcumin

    Sun, Yingqian; Wan, Shuxin; Zhou, Lijun
    Chitosan microparticles (Cs-MPs) for the dissolution and oral bioavailability improvement of curcumin (Cur) were prepared with sodium tripolyphosphate (TPP) by ionotropic gelation method. Response surface methodology (RSM) based on a three-factor, three-level Box-Behnken Design (BBD), was used to optimize the preparative conditions of Cs-MPs. The Cs-MPs were characterized for particle size distribution, morphology, X-ray diffractometry, Fourier transform infrared spectroscopy, dissolution profiles, and oral absorption. The optimum conditions were found to be: 1 % of acetic acid concentration, 0.83 of Cs/Cur ratio, 0.15 % of TPP concentration. Loading capacity, encapsulation efficiency and yield of the optimized Cs-MPs were 62.92, 95.41, and...

  8. Assessment of Pharmaceutical Equivalence: Difference Test or Equivalence Test?

    Lourenço, Felipe R.; Pinto, Terezinha J. A.
    Pharmaceutical equivalence is an important step towards the confirmation of similarity and interchangeability among pharmaceutical products, particularly regarding those that will not be tested for bioequivalence. The aim of this paper is to compare traditional difference testing to two one-side equivalence tests in the assessment of pharmaceutical equivalence, by means of equivalence studies between similar, generic and reference products of acyclovir cream, atropine sulfate injection, meropenem for injection, and metronidazole injection. All tests were performed in accordance with the Brazilian Pharmacopeia or the United States Pharmacopeia. All four possible combinations of results arise in these comparisons of difference testing and...

  9. Fosinopril improves liver fibrosis by upregulating ACE2/Angiotensin-(1-7) axis activation in rats with nonalcoholic steatohepatitis

    Liu, Bo; Wu, Rong; Zhang, Wei; Zhang, Feng; Zhou, Huamei; Wang, Lulu; Xiao, Xiaoqiu; Zhang, Xia; Wu, Xiaoling
    The aim of this research was to evaluate the effect of the angiotensin converting enzyme (ACE) inhibitor fosinopril on liver fibrosis in rats with high fat diet (HFD) induced nonalcoholic steatohepatitis (NASH). We found that treatment with fosinopril improved liver fibrosis. Moreover, treatment with fosinopril decreased serum Angiotensin (Ang) II, leptin, transforming growth factor β1 and hyaluronic acid concentrations, increased serum ACE2, Ang-(1-7), and adiponectin concentrations in rats fed with HFD. In the liver, fosinopril led to decreased leptin, α-smooth muscle actin, and collagen I expression, increased ACE2 and adiponectin expression. In conclusion, Fosinopril improves liver fibrosis by upregulating ACE2/Ang-(1-7)...

  10. Analytical considerations for the successful evaluation of hyoscyamine biotransformation into 6β-hydroxyhyoscyamine and scopolamine

    Cardillo, Alejandra B.; Rodríguez Talou, Julián; Giulietti, Ana María
    Hyoscyamine, 6β-hydroxyhyoscyamine and scopolamine are anticholinergic agents that belong to the tropane alkaloids, a pharmacological important group of secondary metabolites. Hyoscyamine and scopolamine were historically used in medicine. Additionally, potential medical applications for 6β- hydroxyhyoscyamine were described in the last years. Previous works carried out in our lab allowed us the construction of a Saccharomyces cerevisiae strain harboring the Hyoscyamine-6β-hydroxylase (H6H) enzyme which is responsible of the conversion of hyoscyamine into 6β-hydroxyhyoscyamine and scopolamine. Several factors influenced and complicated the optimization of the hyoscyamine bioconversion process. The aim of this work was to evaluate the analytical factors that critically affect...

  11. Factors associated with the use of hypoglycemic and antihypertensive drugs among the elderly, living in a south-eastern capital city of Brazil

    Gontijo, Mônica F.; Ribeiro, Andréia Q.; Klein, Carlos H.; Rozenfeld, Suely; Acurcio, Francisco de A.
    Age-related transformations make the elderly more susceptible to medicine adverse events, and knowledge of factors associated with drug use are essential to develop national strategies of prescription. To estimate the prevalence of use of antihypertensive and hypoglycemic agents and investigate the factors associated with their consumption. Household survey among 667 elderly living in Belo Horizonte/MG, interviewed regarding socio-demographic indicator of health conditions and medication use. Univariate and multivariate analysis were performed. Among respondents, 62 % used antihypertensive and 12 % hypoglycemic drugs. Consumption of antihypertensive drugs was associated with a higher number of medical appointments, diabetes and hypertension, more cases of...

  12. Treatment outcomes of new smear positive pulmonary tuberculosis patients in north east Libya

    Solliman, Mukhtar A; Hassali, Mohamed A.; Al-Haddad, Mahmoud Sadi; Sulaiman, Syed Azhar Syed; Atif, Muhammad; Saleem, Fahad
    A retrospective study conducted in North East of Libya to evaluate treatment outcome of smear positive pulmonary tuberculosis (PTB) patients and factors associated with unsuccessful outcome and treatment default has been developed. Three hundred and twenty seven patients were notified in Kuwaifia chest hospital, Benghazi and Shahat chest hospital, Shahat, during 2007-2008. Using the World Health Organization criteria, treatment completion and cure rate was 1.2 % and 57.5 %, respectively. Treatment failure occurred in 7(2.1 %) cases. Ninety (27.5 %) patients defaulted treatment, 11 (3.4 %) died and 26 (8 %) transferred out. Over all, successful and unsuccessful treatment outcome was...

  13. Structurally modified celecoxib analogues for selective COX-2 inhibition: a classical hansch QSAR approach

    Manivannan, E.; Moorthy, N.S.H.N.
    Classical Hansch type quantitative structure-activity relationship (QSAR) has been performed on a set of structurally modified celecoxib analogues for their inhibitory potency and selectivity towards cyclooxygenase isozymes using classical physicochemical and structural parameters. Statistically significant regression models were developed for cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) inhibitory potency as well as selectivity index. The results of our QSAR study suggest the importance of the molecular size, shape and electronic character of the aromatic ring substituents. Further our investigation provides important structural and physicochemical features for designing potent and selective COX-2 inhibitors within the congener series of compounds.

  14. Determination of folic acid and its related substances of the ferrous fumarate and folic acid dispersible tablet by HPLC

    Chen, Qiaoyun; Liu, Yang; Luo, Y.H.; Luo, M.; Luo, L.Y.
    The aim of the present study was to establish a method for the determination of folic acid and related substances content in dispersible tablets. Method: A Shim-pack VP-ODS C18 reversed phase column (4.6 mm × 250 mm) was used. The mobile phase consisted of methanol-phosphate buffer (20:80) with a pH of 6.3.The flow rate was 1.0 mL/min, and the detection wavelength was 277nm and the column temperature was 30 °C. Results: The calibration curve was linear in the range of 5~150 μg/mL (r = 0.9998) for folic acid. The minimal detection limit was 99.08 %, n = 9 and the...

  15. Stability assessment of cinnarizine in self-emulsifying drug delivery systems

    Shahba, Ahmad A.; Alanazi, Fars K.; Mohsin, Kazi; Abdel-Hamid, Magdi
    The current study was designed to evaluate the chemical and physical stability of cinnarizine within self-emulsifying drug delivery systems. According to International Conference of Harmonization guidelines, the selected formulations were enrolled into both accelerated and long-term stability studies up to 6 and 12 months, respectively. The chemical stability of the formulations was assessed periodically based on the intact cinnarizine level. The physical stability was evaluated based on the physical appearance and color change pattern of the formulations. The accelerated stability study revealed significant cinnarizine degradation in all the tested formulations at 3 and 6 months. All the tested formulations experienced...

  16. Essential oil from eucalyptus benthamii Maiden et Cambage reduces nitric oxide production in lipopolysaccharide-induced murine peritoneal macrophages

    Döll-Boscardini, Patrícia M.; Almeida, Martinha A.; Nakashima, Tomoe; Paula, Josiane de F. Padilha de; Kanunfre, Carla C.; Farago, Paulo V.
    Few studies are concerned about the essential oil extracted from leaves of Eucalyptus benthamii Maiden et Cambage that shows high content of α-pinene. The goal of this paper was to investigate the in vitro effect of the essential oil of E. benthamii and α-pinene on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse peritoneal macrophages. Macrophages were harvested by washing with phosphate buffered saline and cultured with 10 μg/mL LPS. Three concentrations (5, 10, and 20 μg/mL) of the essential oil of E. benthamii and α-pinene were investigated. Nitrite levels were measured based on the Griess reaction, an indirect assay...

  17. Comparative review of biochemistry and cell anatomy of the hepatic tissue in rats administered some anti hypertensive drug for a long time

    Malkoc, Ismail; Cetin, Nihal; Altuner, Durdu; Hacimuftuoglu, Ahmet; Gursan, Nesrin; Bakan, Ebubekir; Akcay, Fatih; Suleyman, Halis
    The adverse biochemical and structural effects of antihypertensive drugs over a long period (clonidine, methyldopa, rilmenidine, amlodipine, ramipril) on hepatic tissue has been examined in this study. The results are considered to be beneficial for the identification of indications and contraindications in hypertensive patients. Severe bile duct proliferation, portal inflammation, interface hepatitis, focal necrosis and hepatocyte degeneration were demonstrated in the clonidine and amlodipine groups, which had higher oxidant parameters, aspartate aminotransferase, alanine amino transferase and lactate dehydrogenase activity and a higher amount of 8-OH Gua. In the group receiving rilmenidine, all the histopathological findings were the same as those...

  18. Simultaneous determination of midazolam and 1’-hydroxymidazolam in rat plasma by protein precipitation and LC-MS: application to pharmacokinetic study

    Chen, Xiaole; Xu, Tao; Wang, Zhe; Pan, Peipei; Luo, Shunbing; Lin, Dan; Hu, Guoxin; Pan, Jianchun
    A sensitive and selective liquid chromatography–mass spectrometry (LC–MS) method for determination of midazolam and its metabolite 1’-hydroxymidazolam in rat plasma was developed and validated. After addition of carbamazepine as internal standard (IS), protein precipitation by acetonitrile was used as sample preparation. The chromatographic separation was performed on a Zorbax SB-C18 column (150 × 2.1 mm, 5 μm), using acetonitrile-0.1 % formic acid as the mobile phase with gradient elution, delivered at a flow-rate of 0.4 mL/min. Electrospray ionization (ESI) source was applied and operated in positive ion mode, and selected ion monitoring (SIM) mode used to quantify midazolam and its...

  19. Leaf microscopic characters of ormosia arborea (vell.) harms, fabaceae

    Duarte, Márcia do Rocio; Dranka, Elize R. K.; Yano, Mami
    The genus Ormosia (Fabaceae-Faboideae) is common in the neotropics and includes different species used in folk medicine for various purposes. Ormosia arborea is a tree popularly known as “olho-decabra” and used for its contraceptive effects in Brazilian rural communities. As it lacks data about this medicinal plant, this work has carried out anatomical studies on the leaf of this potential vegetal drug. Fully-expanded leaves were fixed and prepared according to light and scanning electron microscopic techniques. Microchemical tests were also carried out. The leaf has paracytic stomata confined to the abaxial side. The cuticle is smooth and there are bicellular non-glandular trichomes predominantly on...

  20. Antinociceptive effect of terminalia bellirica in diabetic peripheral neuropathy: a comparison with fluoxetin, imipramine and quercetin

    Rao, Ganji Srinivas; Karimian, Hamed; Razavi, Mahboubeh; Kumar, Nanjundan Prem; Khajuria, Deepak Kumar; Srinivas, Pradeep; Sahebrao, Devkar Satish
    The present study was undertaken to evaluate the possible antinociceptive effect of Terminalia bellirica fruit aqueous extract in animal models of diabetic neuropathic pain. Diabetes was induced by streptozotocin (50 mg/kg i.p.). T. bellirica (70 mg/kg), fluoxetine (14.5 mg/kg), imipramine (10.5 mg/kg) and quercetin (10 mg/kg) were administered orally for 21 consecutive days, starting after 4th week in streptozotocin induced diabetic rats. Hot plate test, tail immersion test and formalin test were used to assess the antinociceptive activity. For assessment of the role of opioid receptors in antinociception of T. bellirica, naloxone (2 mg/kg, i.p.) as opioid receptor antagonist was...

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