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1.
Clin Transl Radiat Oncol ; 43: 100688, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37854671

RESUMO

Purpose: To provide straightforward instructions for daily practice in delineating emerging organs-at-risk (OARs) of the female pelvis and to discuss the interobserver variability in a two-step multicenter study. Methods and materials: A contouring atlas with anatomical boundaries for each emerging OAR was realized by radiation oncologists and radiologists who are experts in pelvic imaging, as per their knowledge and clinical practice. These contours were identified as quality benchmarks for the analysis subsequently carried out. Radiation oncologists not involved in setting the custom-built contouring atlas and interested in the treatment of gynecological cancer were invited to participate in this 2-step trial. In the first step all participants were supplied with a selected clinical case of locally advanced cervical cancer and had to identify emerging OARs (Levator ani muscle; Puborectalis muscle; Internal anal sphincter; External anal sphincter; Bladder base and trigone; Bladder neck; Iliac Bone Marrow; Lower Pelvis Bone Marrow; Lumbosacral Bone Marrow) based on their own personal knowledge of pelvic anatomy and experience. The suggested OARs and the contouring process were then presented at a subsequent webinar meeting with a contouring laboratory. Finally, in the second step, after the webinar meeting, each participant who had joined the study but was not involved in setting the benchmark received the custom-built contouring atlas with anatomical boundaries and was requested to delineate again the OARs using the tool provided. The Dice Similarity Coefficient (DSC) and the Jaccard Similarity Coefficient (JSC) were used to evaluate the spatial overlap accuracy of the different volume delineations and compared with the benchmark; the Hausdorff distance (HD) and the mean distance to agreement (MDA) to explore the distance between contours. All the results were reported as sample mean and standard deviation (SD). Results: Fifteen radiation oncologists from different Institutions joined the study. The participants had a high agreement degree for pelvic bones sub-structures delineation according to DICE (IBM: 0.9 ± 0.02; LPBM: 0.91 ± 0.01). A moderate degree according to DICE was showed for ovaries (Right: 0.61 ± 0.16, Left: 0.72 ± 0.05), vagina (0.575 ± 0.13), bladder sub-structures (0.515 ± 0.08) and EAS (0.605 ± 0.05), whereas a low degree for the other sub-structures of the anal-rectal sphincter complex (LAM: 0.345 ± 0.07, PRM: 0.41 ± 0.10, and IAS: 0.4 ± 0.07). Conclusion: This study found a moderate to low level of agreement in the delineation of the female pelvis emerging OARs, with a high degree of variability among observers. The development of delineation tools should be encouraged to improve the routine contouring of these OARs and increase the quality and consistency of radiotherapy planning.

2.
Res Vet Sci ; 145: 177-187, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35219182

RESUMO

The aims of the present study were to evaluate the ability of a subunit vaccine composed of recombinant molecules of α-toxin, ß-toxin, FnBPA and ClfA, formulated with cationic liposomes and CpG-ODN, to confer protection against natural S. aureus intramammary infection (IMI) and to assess the antibody response against the vaccine components. A stringent criterion based on molecular identification of the isolates was used to define IMI. The proportion of animals that developed new S. aureus IMI was higher in the Control group compared with the Vaccine group (reduction of 60.7%), and time to new S. aureus IMI was higher for animals in the Vaccine group compared with animals in the Control group, although not statistically significant. Molecular identification of the isolates allowed the detection of S. aureus pulsotypes that appeared transiently in milk and others that were able to establish IMI, providing a new perspective to define parameters related to the definition of new IMI and cures. Specific IgG, IgG1 and IgG2 levels against the four recombinant proteins included in the vaccine were significantly increased in the vaccinated group and the recombinant α-toxin included in the vaccine generated antibodies that reduced significantly the haemolytic activity of native α-toxin. Data reported in the present study indicate a possible effect on both the proportion of animals developing new IMI and the time to new S. aureus IMI, but the incidence of disease within the study was too low to provide statistical confirmation.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Imunização/veterinária , Lipossomos , Mastite Bovina/epidemiologia , Leite , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/veterinária , Staphylococcus aureus
3.
Pharmazie ; 76(4): 150-154, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33849699

RESUMO

In pediatric wards, topiramate is prescribed as an antiepileptic at non-licensed dosages. Compounding is the best way to obtain topiramate drug adapted to pediatric patients, but this practice requires to control the quality of batches and to manage a stability study to establish a beyond-use-date. With this objective, 6 mg. mL 1 topiramate oral suspension and 9 mg capsules were realized, and our laboratory was mandated for their quality control. Previously described dosing methods did not allow us to determine topiramate content in prescribed preparations. An original HPLC-UV derivatization dosing method of topiramate was validated and was proved to be stability indicating. This derivatization methodology, but also total aerobic microbial count (TAMC) and total combined yeasts and mold count (TYMC) allowed the quality control of topiramate capsules and topiramate suspension. Beyond-use-dates can be attributed with regards to United States Pharmacopoeia recommendations, and a stability study was performed on 6 mg. mL-1 topiramate suspension to confirm empirical data. Topiramate pediatric suspension was found to be stable for two months at +2/+8 °C, one month after opening and one day at ambient temperature.


Assuntos
Anticonvulsivantes/administração & dosagem , Cromatografia Líquida de Alta Pressão/métodos , Composição de Medicamentos/métodos , Topiramato/administração & dosagem , Administração Oral , Anticonvulsivantes/análise , Anticonvulsivantes/química , Cápsulas , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Controle de Qualidade , Suspensões , Temperatura , Fatores de Tempo , Topiramato/análise , Topiramato/química
4.
J Hosp Infect ; 106(2): 258-263, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32745593

RESUMO

BACKGROUND: To reduce the shortage of N95 respirators and surgical masks during the COVID-19 pandemic, stockpiled equipment beyond its expiry date could be released. AIM: Centralized testing of batches of expired surgical masks and N95 for safe distribution to hospital departments saving users time. METHODS: Tests of compliance with health authority directives were developed and carried out on 175 batches of N95 masks and 31 batches of surgical masks from 12th March 2020 to 16 April 2020. Five quality-control tests were performed on batch samples to check: packaging integrity, mask appearance, breaking strength of elastic ties and strength of nose clip test, and face-fit. FINDINGS: Forty-nine per cent of FFP2 mask batches were compliant with directives, 32% of batches were compliant but with some concerns and 19% of batches were non-compliant. For surgical masks, 58% of batches were compliant, 39% of batches compliant but with concerns and 3% of batches were non-compliant. CONCLUSION: The main areas of non-compliance were the breaking strength of the elastic ties and the nose clip but these alone were not considered to make the masks unacceptable. Only mask appearance and face-fit results were decisive non-compliance criteria.


Assuntos
Infecções por Coronavirus/prevenção & controle , Fidelidade a Diretrizes , Máscaras/normas , Exposição Ocupacional/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Controle de Qualidade , Dispositivos de Proteção Respiratória/normas , Ventiladores Mecânicos/normas , Betacoronavirus , COVID-19 , França , Humanos , SARS-CoV-2 , Fatores de Tempo
5.
Pharmazie ; 74(6): 357-362, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31138374

RESUMO

In intensive care, beta-lactams can be reconstituted in 50 mL polypropylene syringes with NaCl 0.9 % and administered for 8 to 12 h at various concentrations with motor-operated syringe pumps. The feasibility and/or the stability of these antibiotic therapies are often poorly known by clinicians. The purpose of this study was to determine the stability of seven antipyocyanic beta-lactam antibiotics and cilastatin under real-life conditions. Stability indicating HPLC methods allowing quantification in pharmaceutical preparations and subsequent stability studies were performed. The stability studies showed that continuous infusion of piperacillin/tazobactam 80/10 mg/mL, of cefepime 20 and 40 mg/mL and of aztreonam 40 and 120 mg/mL can be used over 12 h. Moreover, continuous infusion of cefepime 120 mg/mL can be used over 10 h, whereas meropenem 10 and 20 mg/mL and ceftazidime 40 mg/mL remained stable only over 8 h, and meropenem 40 mg/mL was significantly degraded after 6 h. Finally, imipenem/cilastatin 5/5 mg/mL and piperacillin/tazobactam 320/40 mg/mL should not be used as continuous infusion. These data allow the establishment of protocols of administration of antipyocyanic beta-lactams by continuous infusion. Some of them are not appropriate to this mode of administration (imipenem/cilastatin, piperacillin/ tazobactam 320/40 mg/mL) or must be avoided if possible (ceftazidime 40 mg/mL).


Assuntos
Antibacterianos/química , beta-Lactamas/antagonistas & inibidores , Aztreonam/química , Cefepima/química , Ceftazidima/química , Cilastatina/química , Combinação Imipenem e Cilastatina/química , Imipenem/química , Meropeném/química , Piperacilina/química , Combinação Piperacilina e Tazobactam/química , Tazobactam/química
6.
Pharmazie ; 73(5): 251-259, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724289

RESUMO

The observed increase in cancer led to a continuous rise in anticancer drug preparations in Hospital Centres. The quality and security of these preparations are essential to ensure the efficacy and to limit the risk of iatrogenic toxicity. Several methods have been described to secure the process of preparation (i.e. non-analytical methods for the control during the fabrication; analytical methods for the final product evaluation). These different methods have been presented in many studies, in particular in descriptive studies, but in practice, selecting a method is difficult and related to needs and hospital priorities. Therefore, we decided to conduct this present review focused on various existing methods allowing enhancement in security of anti-cancer drugs preparation process. A proactive hazard analysis method was applied, considering preparation and control steps, to discuss the choice of a method in terms of quality and security and to identify potential risks of failure. The results show that none method is perfect. Methods with the lowest criticality score are the robotization closely followed by Drugcam® in the case of re-labelling of all containers. According to these elements a University Hospital Centre could consider these risk indexesimplementing control methods.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Composição de Medicamentos/métodos , Antineoplásicos/efeitos adversos , Técnicas de Química Analítica/métodos , Humanos , Medicina de Precisão/métodos , Avaliação de Processos em Cuidados de Saúde , Controle de Qualidade , Gestão de Riscos/métodos , Robótica , Gestão da Segurança/métodos
7.
Ann Pharm Fr ; 76(3): 242-247, 2018 May.
Artigo em Francês | MEDLINE | ID: mdl-29037451

RESUMO

OBJECTIVES: In a hospital environment, the quality control of the hospital preparations allows to release homogeneous batches in a secure way. These controls are totally integrated into the process of production and can also, in certain cases, be realized for high-alert magistral preparations. In community pharmacy, these controls were not required, but the Agence régionale de santé (ARS) recently incited compounding community pharmacies to realize this type of analyses. This decision motivated the creation of a collaboration between the pharmacy department of a French teaching hospital and a society including around thirty community pharmacies having a preparatory. METHODS: Twenty community pharmacies distributed on all the territory have submitted one of their pediatric preparation, capsules of captopril 2mg, to the pharmacopoeia controls usually realized in the industry or hospital. RESULTS: All the analyzed batches were in agreement with European Pharmacopeia specifications. CONCLUSIONS: We shall present the rational of this work, the results as well as the numerous perspectives offered by this new type of collaboration joining completely the logic of a network city-hospital allowing the improvement of security of the medication circuit in France.


Assuntos
Hospitais Urbanos/organização & administração , Preparações Farmacêuticas/normas , Controle de Qualidade , França , Humanos , Farmácias , Serviço de Farmácia Hospitalar
8.
Pharmazie ; 72(12): 741-746, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29441959

RESUMO

Several ocular infections require anti-infectious eye drops prepared by hospital pharmacy. Stability of these preparations is described in the literature, but studies do not always adequately consider physico-chemical parameters or storage conditions. We describe herein a complete study conducted on five anti-infectious eye drops containing vancomycin, gentamicin, ceftazidime, amphotericin B and voriconazole. We looked for significant changes in active pharmaceutical ingredient content, pH, osmolality and subvisible particles. Our study was designed to monitor stability at ambient temperature, at 2-8 °C, and also at 2-8 °C after various freezing periods. Under ambient storage conditions, eye drops were stable for 15 days, except for ceftazidime, which was stable for less than 1 day only. Under refrigeration conditions (2-8 °C), amphotericin B and voriconazole were stable for 60 days, vancomycin and gentamicin were stable for 30 days while ceftazidime was only stable for 15 days. After 90 days freezing and thawing, voriconazole remained stable at 2-8 °C for 60 days, vancomycin and amphotericin B for 30 days and gentamicin only for 21 days. Ceftazidime eye drops were stable for only 7 days at 2-8 °C after 60 days freezing. Our results are compared to the most relevant publications. Results of this study allow the compounding of large batches of harmonized anti-infectious eye drops.


Assuntos
Antibacterianos/química , Antifúngicos/química , Antibacterianos/administração & dosagem , Antifúngicos/administração & dosagem , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Congelamento , Concentração de Íons de Hidrogênio , Soluções Oftálmicas , Concentração Osmolar , Refrigeração , Temperatura , Fatores de Tempo
9.
Pathol Biol (Paris) ; 63(3): 144-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25986879

RESUMO

Neisseria meningitidis infections are a major public health problem worldwide. Although conventional approaches have not led to development of a serogroup B meningococcal vaccine, a new technique based on genome sequencing has created new perspectives. Recently, a universal serogroup B meningococcal vaccine, Bexsero(®), was licensed in Europe, Australia and United States, following several clinical studies demonstrating its immunogenicity and safety. Availability of this vaccine could contribute positively to human health, by significantly reducing the incidence of meningococcal infections. However, unfavorable cost-effectiveness analysis means that routine vaccination is not currently recommended. Another serogroup meningococcal vaccine, Trumemba(®), was also recently licensed in United States. Like any drug, Bexsero(®) and Trumemba(®) will require close observation to assess their impact on meningococcal epidemiology.


Assuntos
Vacinas Meningocócicas , Neisseria meningitidis/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Austrália , Cápsulas Bacterianas/genética , Cápsulas Bacterianas/imunologia , Análise Custo-Benefício , Europa (Continente) , Previsões , Saúde Global , Humanos , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/efeitos adversos , Vacinas Meningocócicas/economia , Vacinas Meningocócicas/imunologia , Nasofaringe/microbiologia , Neisseria meningitidis/classificação , Neisseria meningitidis/isolamento & purificação , Neisseria meningitidis Sorogrupo B/imunologia , Neisseria meningitidis Sorogrupo B/patogenicidade , Seleção Genética , Estados Unidos , Vacinação/economia , Virulência
10.
Pathol Biol (Paris) ; 63(3): 136-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25845294

RESUMO

Hemolytic uremic syndrome is a rare disease, frequently responsible for renal insufficiency in children. Recent findings have led to renewed interest in this pathology. The discovery of new gene mutations in the atypical form of HUS and the experimental data suggesting the involvement of the complement pathway in the typical form, open new perspectives for treatment. This review summarizes the current state of knowledge on both typical and atypical hemolytic uremic syndrome pathophysiology and examines new perspectives for treatment.


Assuntos
Síndrome Hemolítico-Urêmica/fisiopatologia , Animais , Antibacterianos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Infecções Bacterianas/complicações , Toxinas Bacterianas/efeitos adversos , Ensaios Clínicos como Assunto , Proteínas do Sistema Complemento/fisiologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/microbiologia , Previsões , Predisposição Genética para Doença , Síndrome Hemolítico-Urêmica/classificação , Síndrome Hemolítico-Urêmica/etiologia , Síndrome Hemolítico-Urêmica/genética , Síndrome Hemolítico-Urêmica/microbiologia , Síndrome Hemolítico-Urêmica/terapia , Humanos , Transplante de Rim , Transplante de Fígado , Camundongos , Papio , Plasma , Substitutos do Plasma , Toxina Shiga/efeitos adversos , Escherichia coli Shiga Toxigênica/imunologia , Escherichia coli Shiga Toxigênica/patogenicidade , Trombofilia/etiologia , Fator A de Crescimento do Endotélio Vascular/uso terapêutico
11.
Infection ; 41(4): 783-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23543436

RESUMO

PURPOSE: Data regarding the implementation of state-of-the-art methicillin-resistant Staphylococcus aureus (MRSA) control procedures in Italy are lacking. There is a need to evaluate compliance with MRSA recommendations (CR) in Italian hospitals. METHODS: A 67-question closed-answer survey was sent to all Italian hospitals, in order to analyze and evaluate program consistency with CR [hand hygiene (HH), contact precautions, screening of high-risk patients, decolonization, feedback on surveillance data, and antimicrobial guidelines and education programs]. RESULTS: 205 hospitals, which account for 42 % of national admissions, returned questionnaires. 131 hospitals (64 %) did not have written MRSA control guidelines. Hospitals reported the following levels of compliance with CR: (1) HH: 67 hospitals (33 %); (2) contact precautions: 33 (16 %); (3) MRSA screening: 66 (32 %); (4) MRSA decolonization: 42 (20 %); (5) surveillance data feedback: 87 (43 %); and (6) antimicrobial guidelines and education programs: 41 (20 %). One hospital (0.5 % of responses) had implemented all recommendations and 28 hospitals (14 %) had implemented four or five recommendations. 31 % of hospitals surveyed had implemented none. Multivariate analysis showed that the only factor identified as being associated with the implementation of MRSA control recommendations was the number of meetings/year of the infection control team (ICT) (p = 0.004). CONCLUSIONS: Written MRSA control guidelines are available in only one-third of Italian facilities. An organized system, with ≥4 interventions, has been implemented in just 1 out of 7 hospitals. HH programs and ICT activity are related to better MRSA control. In Italy, there is significant opportunity for improvement in MRSA control.


Assuntos
Pesquisa sobre Serviços de Saúde , Controle de Infecções/métodos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Fidelidade a Diretrizes/estatística & dados numéricos , Hospitais , Humanos , Itália/epidemiologia , Infecções Estafilocócicas/microbiologia , Inquéritos e Questionários
12.
Arzneimittelforschung ; 62(12): 583-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23115059

RESUMO

Reactive oxygen species (ROS) are important mediators in a number of neurodegenerative diseases and molecules capable of scavenging ROS may be a feasible strategy for protecting neuronal cells. We previously demonstrated a powerful iron-chelating action of Guttiferone-A (GA), a naturally occurring polyphenol, on oxidative stress injuries initiated by iron overload. Here we addressed the neuroprotective potential of GA in hydrogen peroxide and glutamate-induced injury on rat's primary culture of cortical neurons and PC12 cells, respectively, and antioxidant properties concerning scavenging and anti-lipoperoxidative activities in cell-free models. The decrease in cell viability induced by each of the toxins, assessed by [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT) assay, was significantly attenuated by GA. In addition, GA was found to be a potent antioxidant, as shown by (i) inhibition of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical reduction (EC50=20.0 µM), (ii) prevention against chemically or electrochemically generated superoxide radicals, (iii) inhibition of spontaneous brain lipid peroxidation and (iv) interference with the Fenton reaction. These results indicate that GA exerts neuroprotective effects against H2O2 or glutamate toxicity and its antioxidant activity, demonstrated in vitro, could be at least partly involved. They also suggest a promising potential for GA as a therapeutic agent against neurodegenerative diseases involving ROS and oxidative damage.


Assuntos
Benzofenonas/farmacologia , Sequestradores de Radicais Livres , Fármacos Neuroprotetores , Animais , Compostos de Bifenilo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Corantes , Eletroquímica , Frutas/química , Garcinia/química , Ácido Glutâmico/toxicidade , Humanos , Peróxido de Hidrogênio , Ferro , Peroxidação de Lipídeos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células PC12 , Picratos/metabolismo , Prenilação , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sais de Tetrazólio , Tiazóis
13.
Leukemia ; 26(3): 451-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21869839

RESUMO

The vitamin E derivative (+)α-tocopheryl succinate (α-TOS) exerts pro-apoptotic effects in a wide range of tumors and is well tolerated by normal tissues. Previous studies point to a mitochondrial involvement in the action mechanism; however, the early steps have not been fully elucidated. In a model of acute promyelocytic leukemia (APL) derived from hCG-PML-RARα transgenic mice, we demonstrated that α-TOS is as effective as arsenic trioxide or all-trans retinoic acid, the current gold standards of therapy. We also demonstrated that α-TOS induces an early dissipation of the mitochondrial membrane potential in APL cells and studies with isolated mitochondria revealed that this action may result from the inhibition of mitochondrial respiratory chain complex I. Moreover, α-TOS promoted accumulation of reactive oxygen species hours before mitochondrial cytochrome c release and caspases activation. Therefore, an in vivo antileukemic action and a novel mitochondrial target were revealed for α-TOS, as well as mitochondrial respiratory complex I was highlighted as potential target for anticancer therapy.


Assuntos
Arsenicais/uso terapêutico , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Leucemia Promielocítica Aguda/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Óxidos/uso terapêutico , Tretinoína/uso terapêutico , alfa-Tocoferol/farmacologia , alfa-Tocoferol/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Caspases/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Modelos Animais de Doenças , Complexo II de Transporte de Elétrons/antagonistas & inibidores , Humanos , Leucemia Promielocítica Aguda/mortalidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transplante Isogênico
14.
Chem Biol Interact ; 189(1-2): 45-51, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21044617

RESUMO

Cisplatin is a highly effective chemotherapeutic agent which causes severe nephrotoxicity. Studies have suggested that reactive oxygen species, mainly generated in mitochondria, play a central role in cisplatin-induced renal damage. A wide range of antioxidants have been evaluated as possible protective agents against cisplatin-induced nephrotoxicity; however a safe and efficacious compound has not yet been found. The present study is the first to evaluate the protective potential of carvedilol, a beta-blocker with strong antioxidant properties, against the mitochondrial oxidative stress and apoptosis in kidney of rats treated with cisplatin. The following cisplatin-induced toxic effects were prevented by carvedilol: increased plasmatic levels of creatinine and blood urea nitrogen (BUN); lipid peroxidation, oxidation of cardiolipin; oxidation of protein sulfhydryls; depletion of the non-enzymatic antioxidant defense and increased activity of caspase-3. Carvedilol per se did not present any effect on renal mitochondria. It was concluded that carvedilol prevents mitochondrial dysfunction and renal cell death through the protection against the oxidative stress and redox state unbalance induced by cisplatin. The association of carvedilol to cisplatin chemotherapy was suggested as a possible strategy to minimize the nephrotoxicity induced by this antitumor agent.


Assuntos
Carbazóis/farmacologia , Cisplatino/toxicidade , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Propanolaminas/farmacologia , Animais , Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Carvedilol , Creatinina/sangue , Interações Medicamentosas , Humanos , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Oxirredução , Ratos , Ratos Wistar , Estatísticas não Paramétricas
15.
Curr Med Chem ; 17(13): 1255-99, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20166941

RESUMO

The outstanding physio-pathological role played by integrin receptors in living subjects motivates the enormous interest shown by scientists worldwide for this topic. More than twenty years of research has spanned across the structural and functional elucidation of these proteins and over their antagonism-based biomedical applications. The proof-of concept stage, aimed at identifying potent inhibitors, covered a decade of studies, and paved the way for a more advanced era of research where these antagonist molecules were thrown into the deep end of applicative studies. This review intends to summarize the major efforts conducted thus far and focuses on the design, synthesis and biomedical applications of cyclic RGD-containing alpha(v)beta(3) integrin antagonists, in both their small and macromolecular formats. In particular, Chapters 1 and 2 offer a comprehensive outlook on the rational basis for the design of integrin inhibitors, Chapter 3 chronicles the biological and medical applications of monofunctional RGD integrin ligands both in their monomeric and multimeric asset, and Chapter 4 illustrates the potential of RGD-based multifunctional systems in molecular medicine.


Assuntos
Integrina alfaVbeta3/antagonistas & inibidores , Oligopeptídeos/química , Peptídeos/química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Desenho de Fármacos , Humanos , Integrina alfaVbeta3/metabolismo , Ligantes , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Peptídeos/uso terapêutico
16.
Mitochondrion ; 10(1): 46-53, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19772951

RESUMO

The clinical use of cisplatin is highly limited by its nephrotoxicity, which has been associated with mitochondrial dysfunction. We investigated the protective effect of carvedilol, an antihypertensive with strong antioxidant properties, against the nephrotoxicity induced by cisplatin in rats. Carvedilol was able to counteract the renal damage by preventing the mitochondrial dysfunction induced by cisplatin. The mitochondrial eletrochemical potential, calcium uptake, respiration and the phosphorylative capacity were preserved by the co-administration of carvedilol. The mechanism of protection probably does not involve alterations in the cellular and sub-cellular distribution of cisplatin. The study suggests that carvedilol is a potential drug for the adjuvant nephroprotective therapy during cisplatin chemotherapy.


Assuntos
Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Carbazóis/farmacologia , Cisplatino/toxicidade , Nefropatias/prevenção & controle , Mitocôndrias/efeitos dos fármacos , Propanolaminas/farmacologia , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Antineoplásicos/administração & dosagem , Antioxidantes/administração & dosagem , Cálcio/metabolismo , Carbazóis/administração & dosagem , Carvedilol , Cisplatino/administração & dosagem , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/ultraestrutura , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Propanolaminas/administração & dosagem , Ratos , Ratos Wistar
17.
Arch Toxicol ; 83(1): 47-53, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18560806

RESUMO

One hypothesis for the etiology of cell damage arising from iron overload is that its excess selectively affects mitochondria. Here we tested the effects of acute iron overload on liver mitochondria isolated from rats subjected to a single dose of i.p. 500 mg/kg iron-dextran. The treatment increased the levels of iron in mitochondria (from 21 +/- 4 to 130 +/- 7 nmol/mg protein) and caused both lipid peroxidation and glutathione oxidation. The mitochondria of iron-treated rats showed lower respiratory control ratio in association with higher resting respiration. The mitochondrial uncoupling elicited by iron-treatment did not affect the phosphorylation efficiency or the ATP levels, suggesting that uncoupling is a mitochondrial protective mechanism against acute iron overload. Therefore, the reactive oxygen species (ROS)/H+ leak couple, functioning as a mitochondrial redox homeostatic mechanism could play a protective role in the acutely iron-loaded mitochondria.


Assuntos
Sobrecarga de Ferro/fisiopatologia , Complexo Ferro-Dextran/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Injeções Intraperitoneais , Sobrecarga de Ferro/induzido quimicamente , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias Hepáticas/metabolismo , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
18.
Toxicol In Vitro ; 22(8): 1820-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18783732

RESUMO

The use of the classic aromatic antiepileptic drugs (AAEDs) has recently been expanded to a broad spectrum of psychiatric and neurological disorders. However, the clinical use of these drugs is limited by several adverse effects, mainly idiosyncratic hepatotoxicity. AAED-induced hepatotoxicity has been attributed to a defective detoxification by the epoxide hydrolase and accumulation of arene oxides. The underlying mechanism has been proposed as immune-mediated, but direct toxicity has also been suggested. In general, idiosyncratic drug-induced hepatotoxicity may be mediated, at least in part, by oxidative stress. On the other hand, the oxidative stress induced by the AAED metabolites has not been demonstrated yet. Therefore, in the present study we have evaluated the induction of oxidative stress by three classical AAEDs: carbamazepine, phenytoin and phenobarbital as well as by their metabolites. The toxic effects of the metabolites were evaluated by incubating the drug with rat liver microsomes. The AAED-induced oxidative stress was demonstrated by the increased malondialdehyde levels, oxidation of cardiolipin; oxidation of sulfhydryl proteins and alteration of the cellular redox status. Results suggest that the hepatotoxicity associated with AAED might be mediated by the oxidative stress induced by the drugs metabolites.


Assuntos
Anticonvulsivantes/toxicidade , Fígado/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Anticonvulsivantes/metabolismo , Carbamazepina/metabolismo , Carbamazepina/toxicidade , Cardiolipinas/efeitos dos fármacos , Cardiolipinas/metabolismo , Masculino , Malondialdeído/metabolismo , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Fenobarbital/metabolismo , Fenobarbital/toxicidade , Fenitoína/metabolismo , Fenitoína/toxicidade , Ratos , Ratos Wistar , Compostos de Sulfidrila/metabolismo , Testes de Toxicidade
19.
Phytochemistry ; 69(9): 1890-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18479721

RESUMO

The trypanocidal activity of racemic mixtures of cis- and trans-methylpluviatolides was evaluated in vitro against trypomastigote forms of two strains of Trypanosoma cruzi, and in the enzymatic assay of T. cruzi gGAPDH. The cytotoxicity of the compounds was assessed by the MTT method using LLC-MK2 cells. The effect of the compounds on peroxide and NO production were also investigated. The mixture of the trans stereoisomers displayed trypanocidal activity (IC50 approximately 89.3 microM). Therefore, it was separated by chiral HPLC, furnishing the (+) and (-)-enantiomers. Only the (-)-enantiomer was active against the parasite (IC50 approximately 18.7 microM). Despite being inactive, the (+)-enantiomer acted as an antagonistic competitor. Trans-methylpluviatolide displayed low toxicity for LLC-MK2 cells, with an IC50 of 6.53 mM. Furthermore, methylpluviatolide neither inhibited gGAPDH activity nor hindered peroxide and NO production at the evaluated concentrations.


Assuntos
Lactonas/química , Lactonas/farmacologia , Lignanas/química , Lignanas/farmacologia , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Relação Estrutura-Atividade
20.
Toxicol In Vitro ; 22(5): 1143-52, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18434079

RESUMO

Idiosyncratic hepatotoxicity is a well-known complication associated with aromatic antiepileptic drugs (AAED), and it has been suggested to occur due to the accumulation of toxic arene oxide metabolites. Although there is clear evidence of the participation of an immune process, a direct toxic effect involving mitochondria dysfunction is also possible. The effects of AAED on mitochondrial function have not been studied yet. Therefore, we investigated, in vitro, the cytotoxic mechanism of carbamazepine (CB), phenytoin (PT) and phenobarbital (PB), unaltered and bioactivated, in the hepatic mitochondrial function. The murine hepatic microsomal system was used to produce the anticonvulsant metabolites. All the bioactivated drugs (CB-B, PB-B, PT-B) affected mitochondrial function causing decrease in state three respiration, RCR, ATP synthesis and membrane potential, increase in state four respiration as well as impairment of Ca2+ uptake/release and inhibition of calcium-induced swelling. As an unaltered drug, only PB, was able to affect mitochondrial respiration (except state four respiration) ATP synthesis and membrane potential; however, Ca2+ uptake/release as well as swelling induction were not affected. The potential to induce mitochondrial dysfunction was PT-B>PB-B>CB-B>PB. Results suggest the involvement of mitochondrial toxicity in the pathogenesis of AAED-induced hepatotoxicity.


Assuntos
Anticonvulsivantes/toxicidade , Carbamazepina/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Fenobarbital/toxicidade , Fenitoína/toxicidade , Trifosfato de Adenosina/biossíntese , Animais , Anticonvulsivantes/metabolismo , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Carbamazepina/metabolismo , Relação Dose-Resposta a Droga , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Dilatação Mitocondrial/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Fenobarbital/metabolismo , Fenitoína/metabolismo , Ratos , Ratos Wistar
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