Browsing by Author "Gonzalez Martin, G"

Now showing 1 - 4 of 4
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    Adverse drug reactions (ADRs) in hospitalized pediatric patients. A prospective study
    (DUSTRI-VERLAG DR KARL FEISTLE, 1998) Gonzalez Martin, G; Caroca, CM; Paris, E
    The aim of this study was to determine the frequency and the characteristics of ADRs in 219 hospitalized pediatric patients, using an intensive and prospective drug surveillance method. The frequency of ADRs in these patients was 13.7%. The systems most commonly affected were the gastrointestinal (32.5%), the central nervous (20.0%), and the metabolic systems (17.5%). Asparaginase, methotrexate, phenytoin, phenobarbital, erythromycin, and salbutamol were probably the drugs associated with the ADRs, According to causality, 54.2% of the ADRs were regarded as probable, and 32.2% as possible. The majority of the ADRs were moderate (51.2%), 27.9% were severe. The main treatment of the ADRs was the withdrawal of the suspected drugs. The length of the slay in the hospital and the total number of drugs given to the patients influenced significantly the frequency of ADRs. 93% of the ADRs were dose-dependent.
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    Adverse drug reactions (ADRs) in patients with HIV infection. A prospective study
    (DUSTRI-VERLAG DR KARL FEISTLE, 1999) Gonzalez Martin, G; Yanez, CG; Gonzalez Contreras, L; Labarca, J
    Aim A prospective drug surveillance method was used to monitor 50 ambulatory patients with HIV infection, who were controlled in the Sexual Transmission Disease Service at Dr. Sotero del Rio Hospital (Santiago, Chile). The aim of this work was to characterize and study the frequency, characteristics, and associated factors of the ADRs in HIV-infected patients. Patients and methods: Patients were interrogated once or twice a month by a clinical pharmacist, who consigned data concerning the drug prescribed by the physician, drug-related signs and symptoms, and the laboratory's parameters as renal, hepatic, hematological function, and biochemical test. The ADR probability was assessed for an algorithm. Results: The frequency of adverse drug reactions found in the group of patients studied was 32.0%. The dermatological, hepatic, and hematological systems were the most affected by adverse drug reactions. Trimethroprim-sulfamethoxazole and zidovudine were the drugs mainly associated with ADRs. Patients with lymphocytes CD4+ count of 200 or less, presented a higher frequency of ADRs. 48.5% of ADRs were classified as probable. Severe reactions were found in 18.5% of the patients, and moderate in 70.4%. 50% of patients with ADRs needed the withdrawal of the implicated drug, and an 18.5% dose decreased. 63% gf the ADRs were dose-independent, Conclusion: There was a higher frequency of ADRs in those patients with multiple-drug therapy, but the frequency of ADR was not associated with age, gender, or hematological test.
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    Characterization and trypanocidal activity of nifurtimox-containing and empty nanoparticles of polyethylcyanoacrylates
    (ROYAL PHARMACEUTICAL SOC GREAT BRITAIN, 1998) Gonzalez Martin, G; Merino, I; Rodriguez Cabezas, MN; Torres, M; Nunez, R; Osuna, A
    The aim of this study was to evaluate the utility of nanoparticles of polyalkylcyanoacrylate as a targeted delivery system for nifurtimox against Trypanosoma cruzi, responsible for Chagas' disease. Ethylcyanoacrylate nanoparticles were prepared by an emulsion polymerization process and formulations containing different concentrations of nifurtimox, polyethylcyanoacrylates and surfactants were investigated and analysed for size and drug content.
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    Cytotoxicity and trypanocidal activity of nifurtimox encapsulated in ethylcyanoacrylate nanoparticles
    (SOCIEDAD BIOLGIA CHILE, 2002) Sanchez, G; Cuellar, D; Zulantay, I; Gajardo, M; Gonzalez Martin, G
    The aim of the present study was to study the trypanocidal activity of nanoparticles loaded with nifurtimox in comparison with the free drug against Trypanosoma cruzi, responsible for Chagas' disease. Ethylcyanoacrylate nanoparticles acted as the delivery system into cells. As the obligate replicative intracellular form is amastigote, in vitro studies were performed on this form of parasite as well as on cell culture derived trypomastigotes. The fluorescence method used here was very useful as it allowed for the simultaneous study of trypanocide activity and cytotoxicity by determining living or dead parasites within living or dead host cells. According to these results, the greatest trypanocide activity on cell culture-derived trypomastigotes was recorded for nifurtimox-loaded nanoparticles with a 50% inhibitory concentration (IC50) twenty times less than that of the free drug. The cytotoxycity of unloaded nanoparticles at low concentrations was similar to that obtained by free drug when evaluated on Vero cells. Furthermore, nifurtimox-loaded nanoparticles showed increased trypanocide activity on intracellular amastigotes with an IC50 thirteen times less than that of nifurtimox. We also observed that the unloaded nanoparticles possess the previously-described trypanocide activity, similar to the standard solution of nifurtimox, although the mechanism for this has not yet been elucidated. In conclusion, it was possible to establish in vitro conditions using nifurtimox encapsulated nanoparticles in order to decrease the doses of the drug and thus to obtain high trypanocidal activity on both free trypomastigotes and intracellular amastigotes with low cytotoxicity for the host cell.