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1.
Gut ; 63(7): 1150-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24201995

RESUMO

BACKGROUND AND AIM: Severe adverse events (AEs) compromise the outcome of direct antiviral agent-based treatment in patients with advanced liver fibrosis due to HCV infection. HEP3002 is an ongoing multinational programme to evaluate safety and efficacy of telaprevir (TVR) plus pegylated-interferon-α (PEG-IFNα) and ribavirin (RBV) in patients with advanced liver fibrosis caused by HCV genotype 1 (HCV-1). METHODS: 1782 patients with HCV-1 and bridging fibrosis or compensated cirrhosis were prospectively recruited from 16 countries worldwide, and treated with 12 weeks of TVR plus PEG-IFN/RBV, followed by 12 or 36 weeks of PEG-IFN and RBV (PR) alone dependent on virological response to treatment and previous response type. RESULTS: 1587 patients completed 12 weeks of triple therapy and 4 weeks of PR tail (53% cirrhosis, 22% HCV-1a). By week 12, HCV RNA was undetectable in 85% of naives, 88% of relapsers, 80% of partial responders and 72% of null responders. Overall, 931 patients (59%) developed grade 1-4 anaemia (grade 3/4 in 31%), 630 (40%) dose reduced RBV, 332 (21%) received erythropoietin and 157 (10%) were transfused. Age and female gender were the strongest predictors of anaemia. 64 patients (4%) developed a grade 3/4 rash. Discontinuation of TVR due to AEs was necessary in 193 patients (12%). Seven patients died (0.4%, six had cirrhosis). CONCLUSIONS: In compensated patients with advanced fibrosis due to HCV-1, triple therapy with TVR led to satisfactory rates of safety, tolerability and on-treatment virological response with adequate managements of AEs.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Cirrose Hepática/virologia , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Genótipo , Hepacivirus/genética , Hepatite C Crônica/complicações , Humanos , Interferon alfa-2 , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Oligopeptídeos/efeitos adversos , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
2.
Antimicrob Agents Chemother ; 55(1): 321-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20956600

RESUMO

The integrase inhibitor raltegravir (RAL) is currently used for the treatment of both treatment-naïve and treatment-experienced HIV-1-infected patients. Elvitegravir (EVG) is in late phases of clinical development. Since significant cross-resistance between RAL and EVG is observed, there is a need for second-generation integrase inhibitors (INIs) with a higher genetic barrier and limited cross-resistance to RAL/EVG. A panel of HIV-1 integrase recombinants, derived from plasma samples from raltegravir-treated patients (baseline and follow-up samples), were used to study the cross-resistance profile of two second-generation integrase inhibitors, MK-2048 and compound G. Samples with Q148H/R mutations had elevated fold change values with all compounds tested. Although samples with the Y143R/C mutation had reduced susceptibility to RAL, they remained susceptible to MK-2048 and compound G. Samples with the N155H mutation had no reduced susceptibility to compound G. In conclusion, our results allowed ranking of the INIs on the basis of the antiviral activities using recombinant virus stocks from RAL-treated patient viruses. The order according to decreasing susceptibility is compound G, MK-2048, and EVG.


Assuntos
Inibidores de Integrase de HIV/farmacologia , HIV-1/efeitos dos fármacos , Humanos , Pirrolidinonas/farmacologia , Quinolonas/farmacologia , Raltegravir Potássico
3.
Rev Med Liege ; 65(2): 103-8, 2010 Feb.
Artigo em Francês | MEDLINE | ID: mdl-20344922

RESUMO

We report the clinical evolution of three adult patients with recurrent respiratory tract infections. Those patients had a low plasma level of IgG3 and/or a deficiency in anti polysaccharide antibodies. They all were previously treated with intravenous immunoglobulin, but their clinical status as well as their health related quality of life improved after they had switched to subcutaneous immunoglobulin administrations. The frequency of subcutaneous injections was on a weekly basis and the dosage was adjusted in order to reach the cumulative monthly dose of intravenous infusions. The tolerance of the subcutaneous route of immunoglobulin injection was recorded as excellent in all three patients.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/diagnóstico , Síndromes de Imunodeficiência/terapia , Adulto , Idoso , Feminino , Humanos , Masculino , Recidiva , Infecções Respiratórias/etiologia
4.
Vet J ; 177(1): 104-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17512765

RESUMO

Although insufficient milk production in lactating sows may cause tremendous economic losses, reliable methods for estimating milk production in sows under field conditions are not available. This study aimed to investigate whether urine parameters could be used to predict milk production in sows. The milk production of 18 sows was determined during early and mid-lactation. Morning (a.m.) and afternoon (p.m.) urinary levels of potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), lactose and creatinine were analysed. The absolute concentrations, the ratios relative to creatinine, and the fractional excretions of all elements in urine were not significantly associated with milk production. The p.m./a.m. ratios of K, Na and Ca concentrations in urine (K(R), Na(R), and Ca(R)) were significant predictors for milk production, but only during mid-lactation. The total variation in milk production (r(2) value) explained by K(R), Na(R), Ca(R) amounted to 72%, 55%, 42%, respectively. Analysis of minerals and especially K in the a.m. and p.m. urine of sows during mid-lactation provided an acceptable indication of milk production. Further research is necessary to investigate whether the present results can be used to estimate milk production in hypogalactic sows under field conditions.


Assuntos
Lactação/urina , Leite/metabolismo , Suínos , Urina/química , Animais , Biomarcadores/urina , Cálcio/urina , Ritmo Circadiano , Feminino , Lactação/fisiologia , Projetos Piloto , Potássio/urina , Sódio/urina , Urinálise/métodos , Urinálise/veterinária
5.
J Biomol Screen ; 21(8): 804-15, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26984927

RESUMO

Tau aggregation is the pathological hallmark that best correlates with the progression of Alzheimer's disease (AD). The presence of neurofibrillary tangles (NFTs), formed of hyperphosphorylated tau, leads to neuronal dysfunction and loss, and is directly associated with the cognitive decline observed in AD patients. The limited success in targeting ß-amyloid pathologies has reinforced the hypothesis of blocking tau phosphorylation, aggregation, and/or spreading as alternative therapeutic entry points to treat AD. Identification of novel therapies requires disease-relevant and scalable assays capable of reproducing key features of the pathology in an in vitro setting. Here we use induced pluripotent stem cells (iPSCs) as a virtually unlimited source of human cortical neurons to develop a robust and scalable tau aggregation model compatible with high-throughput screening (HTS). We downscaled cell culture conditions to 384-well plate format and used Matrigel to introduce an extra physical protection against cell detachment that reduces shearing stress and better recapitulates pathological conditions. We complemented the assay with AlphaLISA technology for the detection of tau aggregates in a high-throughput-compatible format. The assay is reproducible across users and works with different commercially available iPSC lines, representing a highly translational tool for the identification of novel treatments against tauopathies, including AD.


Assuntos
Técnicas de Cultura de Células/métodos , Ensaios de Triagem em Larga Escala/métodos , Tauopatias/tratamento farmacológico , Proteínas tau/química , Encéfalo/metabolismo , Encéfalo/patologia , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Fosforilação , Agregados Proteicos/genética , Tauopatias/genética , Proteínas tau/efeitos dos fármacos , Proteínas tau/genética
6.
Cell Death Differ ; 7(12): 1218-24, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11175259

RESUMO

The epidermis is a stratified squamous epithelium in which keratinocytes progressively undergo terminal differentiation towards the skin surface leading to programmed cell death. In this respect we studied the role of caspases. Here, we show that caspase-14 synthesis in the skin is restricted to differentiating keratinocytes and that caspase-14 processing is associated with terminal epidermal differentiation. The pro-apoptotic executioner caspases-3, -6, and -7 are not activated during epidermal differentiation. Caspase-14 does not participate in apoptotic pathways elicited by treatment of differentiated keratinocytes with various death-inducing stimuli, in contrast to caspase-3. In addition, we show that non-cornifying oral keratinocyte epithelium does not express caspase-14 and that the parakeratotic regions of psoriatic skin lesions contain very low levels of caspase-14 as compared to normal stratum corneum. These observations strongly suggest that caspase-14 is involved in the keratinocyte terminal differentiation program leading to normal skin cornification, while the executioner caspases are not implicated. Cell Death and Differentiation (2000) 7, 1218 - 1224


Assuntos
Apoptose/fisiologia , Caspases/metabolismo , Diferenciação Celular/fisiologia , Epiderme/enzimologia , Epiderme/fisiologia , Animais , Caspase 14 , Caspase 3 , Caspase 6 , Caspase 7 , Células Cultivadas , Células Epidérmicas , Feto , Humanos , Imuno-Histoquímica , Queratinócitos/citologia , Queratinócitos/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Psoríase/enzimologia , Psoríase/patologia , Psoríase/fisiopatologia
7.
Neuroscience ; 301: 204-12, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26047731

RESUMO

Neurodegenerative diseases are difficult to study due to unavailability of human neurons. Cell culture systems and primary rodent cultures have shown to be indispensable to clarify disease mechanisms and provide insights into gene functions. Nevertheless, it is hard to translate new findings into new medicines. The discovery of human induced pluripotent stem cells (iPSC) might partially overcome this problem. Commercially available human iPSC-derived neurons, when thoroughly characterized and suitable for viral transduction, might represent a faster model for drugs screening than the time-consuming derivation and differentiation of iPSC from patient samples. In this study we show that iCell® neurons are primarily immature GABAergic neurons within the tested time frame. Addition of C6 glioma conditioned medium improved the bursting frequency of cells without further maturation or evidence for glutamatergic responses. Furthermore, cells were suitable for lentiviral transduction within the tested time frame. Altogether, iCell® neurons might be useful to model neurodegenerative diseases in which young GABAergic subtypes are affected.


Assuntos
Modelos Animais de Doenças , Neurônios GABAérgicos/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Doenças Neurodegenerativas/fisiopatologia , Animais , Células Cultivadas , Meios de Cultivo Condicionados , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/metabolismo , Vetores Genéticos , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Lentivirus , Análise em Microsséries , Prosencéfalo/citologia , Prosencéfalo/metabolismo , Prosencéfalo/fisiologia
8.
Br J Pharmacol ; 115(7): 1194-8, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7582544

RESUMO

1. An experimental set up is used whereby the serosal (out)side or mucosal (in)side of the guinea-pig isolated tracheal tube can be stimulated selectively with drugs and reactivity measured. 2. Potassium induces a concentration-dependent (5-70 mM) monophasic contraction of tracheal tubes when added on the outside. In contrast, on the inside, potassium induces a concentration-dependent relaxation at low concentrations (5-40 mM) which was reversed into a contraction up to approximately basal tone at higher concentrations (50-70 mM). 3. Epithelium denudation reversed the potassium-induced relaxation into a contraction. Interestingly, in the 'half' epithelium-denuded trachea the contractions were significantly (P < 0.01) reduced by 46% compared to complete epithelium-denuded tissues. 4. Incubation with the nitric oxide (NO) synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME, 120 microM) for 30 min on the inside of the tracheal tube completely prevented the relaxation. However, L-NAME did not reverse the potassium-induced relaxation into a contraction. This indicates that potassium does not penetrate through the epithelial layer. 5. It is concluded that depolarization of smooth muscle cells leads to a monophasic contraction and that depolarization of the epithelium leads to a relaxation of tracheal smooth muscle. The epithelial layer has an important barrier function and can release relaxing factors like NO.


Assuntos
Óxido Nítrico/fisiologia , Potássio/farmacologia , Traqueia/efeitos dos fármacos , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Inibidores Enzimáticos/farmacologia , Cobaias , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintase/antagonistas & inibidores
9.
Eur J Pharmacol ; 228(2-3): 121-30, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1280227

RESUMO

In the present study an animal model is described in which a sustained non-specific airway hyperresponsiveness is induced. Guinea pigs were inoculated intratracheally with parainfluenza type 3 (PI-3) virus or control solution. Two, 4, 8, and 16 days after inoculation the tracheae, bronchi, and lung strips were isolated and mounted in organ baths. Two days after inoculation no difference between the control solution and PI-3 virus group was observed, with respect to the histamine concentration/response curve obtained from tracheae, bronchi and lung strips of the respective groups. However, histamine concentration/response curves were significantly (P less than 0.01) shifted upwards in all parts of the airways 4, 8, and 16 days after PI-3 inoculation as compared with the control solution. The excessive contraction of the trachea was not specific for histamine, since an increase in the maximal response was obtained also for the cholinergic receptor agonist, arecoline on day 4 (32%, P less than 0.05), day 8 (24%, P less than 0.05), and day 16 (28%). Morphological examination of the central airways obtained from control solution-inoculated animals revealed no signs of inflammation. However, 2, 4, and 8 days, but not 16 days, after the viral infection, epithelial damage with loss of cilia and mucus-depleted goblet cells were observed. Thus, morphological changes were not directly associated with changes in airway responsiveness. Histological examination of the peripheral airways revealed an influx of inflammatory cells, as shown by typical lesions of patchy alveolitis and bronchiolitis. Bronchiolar epithelium was variously hyperplastic and dysplastic with degenerative changes, and the lumens of the bronchioli were occluded with mucus and inflammatory cells. In conclusion, the virus-induced airway hyperresponsiveness in guinea pigs shows similarities with the human situation, in which a sustained non-specific airway hyperresponsiveness is observed after a respiratory viral infection. In addition, the hyperresponsiveness seems to be accompanied by an influx of inflammatory cells in the airways but not with other morphological changes.


Assuntos
Pulmão/metabolismo , Vírus da Parainfluenza 3 Humana , Infecções por Paramyxoviridae/metabolismo , Hipersensibilidade Respiratória/metabolismo , Traqueia/metabolismo , Animais , Brônquios/metabolismo , Brônquios/patologia , Cobaias , Liberação de Histamina , Masculino , Hipersensibilidade Respiratória/patologia , Traqueia/patologia
10.
Eur J Pharmacol ; 194(2-3): 209-16, 1991 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-2060602

RESUMO

A buffered solution was perfused at a constant flow rate (2 ml/min) through both iliac arteries in rat hindquarters. Perfusion pressures were measured in normal and collateralized vascular beds of the left and right hind-leg, respectively. Bolus injections of various agonists produced concentration-dependent increases in perfusion pressure in both collateralized and normal circulatory beds. Serotonin, in particular, and noradrenaline, to a lesser extent, produced more pronounced vasoconstriction on the collateral side than on the normal side. The difference in vasoreactivity to serotonin was related to a difference in both vascular structure and sensitivity of both types of vascular bed. Vasoconstriction induced by serotonin was inhibited by 5-HT2 antagonists. Selective blockade of alpha 1,alpha 2,beta 1-beta 2 adrenoceptors and amine uptake blockade were ineffective. This study indicates that, in rat hind-legs, the collateralized vascular bed is superreactive to serotonin in comparison with the normal bed. This resetting of reactivity to serotonin is due to the specific vascular structure as well as to an increased 5-HT2 receptor-mediated sensitivity.


Assuntos
Circulação Colateral/efeitos dos fármacos , Serotonina/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Circulação Colateral/fisiologia , Membro Posterior/irrigação sanguínea , Masculino , Perfusão , Ratos , Ratos Endogâmicos , Antagonistas da Serotonina , Vasoconstrição/fisiologia
11.
Eur J Pharmacol ; 293(4): 401-12, 1995 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-8748694

RESUMO

To investigate the mechanisms underlying airway hyperresponsiveness a murine model was developed with several important characteristics of human allergic asthma. Mice were intraperitoneally sensitized with ovalbumin and after 4 weeks challenge via an ovalbumin aerosol. After aerosol, lung function was evaluated with a non-invasive forced oscillation technique. The amount of mucosal exudation into the airway lumen and the presence of mast cell degranulation was determined. Tracheal responsiveness was measured at several time points after challenge. At these time points also bronchoalveolar lavage and histology were performed. Sensitization induced high antigen-specific IgE levels in serum. Inhalation of ovalbumin in sensitized mice induced an immediate but no late bronchoconstrictive response. During this immediate phase, respiratory resistance was increased (54%). Within the first hour after ovalbumin inhalation increased mucosal exudation and mast cell degranulation were observed. At 12 and 24 h after ovalbumin challenge, mice showed tracheal hyperresponsiveness (29% and 34%, respectively). However, no apparent inflammation was found in the lungs or bronchoalveolar lavage. From these results it can be concluded that hyperresponsiveness can develop via mechanisms independent of an inflammatory infiltrate. Since mast cell degranulation occurred after ovalbumin exposure, we hypothesize that mast cells are involved in the induction of airway hyperresponsiveness in this model.


Assuntos
Hiper-Reatividade Brônquica/induzido quimicamente , Ovalbumina/imunologia , Hipersensibilidade Respiratória/induzido quimicamente , Animais , Lavagem Broncoalveolar , Broncoconstrição , Dermatite Alérgica de Contato/etiologia , Exsudatos e Transudatos , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Técnicas In Vitro , Pulmão/patologia , Masculino , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Traqueia/patologia
12.
Blood Coagul Fibrinolysis ; 1(3): 247-58, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2151728

RESUMO

Platelet-dependent occlusive thrombosis at sites of deep vessel wall injury elicited by electrical stimulation of rat carotid arteries was significantly reduced by thromboxane A2 (TXA2) synthetase inhibition and/or TXA2/prostaglandin endoperoxide receptor antagonism (ridogrel 1.25 mg/kg i.v.; dazoxiben 5 mg/kg i.v.; sulotroban 20 mg/kg i.v.), by inhibition of ADP-dependent platelet responses (ticlopidine 3 x 200 mg/kg orally) and by anticoagulation (heparin 250 U/kg i.v.; warfarin 1.25 mg/kg i.p.). This points to an involvement of arachidonic acid metabolites, ADP and thrombin as modulators of the thrombotic process. The antithrombotic effect of ridogrel (IC50 = 0.22 mg/kg i.v.) was abolished by cyclooxygenase inhibition (suprofen 5 mg/kg i.v.) but enhanced by cAMP phosphodiesterase inhibition (HL 725 6 micrograms/kg/min i.v.), demonstrating the importance of platelet inhibitory prostanoids such as PGD2, and prostacyclin formed after TXA2 synthetase inhibition. High doses of ridogrel (1.25 mg/kg i.v.) producing additional TXA2/prostaglandin endoperoxide receptor antagonism were more effective than lower doses (0.16 mg/kg i.v.) providing TXA2 synthetase inhibition alone. The antithrombotic effect of ridogrel, when combined with ticlopidine or heparin, exceeded that of the single compounds, pointing to interactions between arachidonic acid metabolites, ADP and thrombin in the formation of occlusive thrombosis at sites of arterial injury.


Assuntos
Difosfato de Adenosina/fisiologia , Ácidos Araquidônicos/metabolismo , Plaquetas/fisiologia , Trombose das Artérias Carótidas/fisiopatologia , Trombina/fisiologia , Animais , Anticoagulantes/farmacologia , Ácido Araquidônico , Coagulação Sanguínea , Trombose das Artérias Carótidas/etiologia , Trombose das Artérias Carótidas/prevenção & controle , Estimulação Elétrica , Heparina/farmacologia , Masculino , Ácidos Pentanoicos/farmacologia , Piridinas/farmacologia , Ratos , Ratos Endogâmicos , Receptores de Prostaglandina/antagonistas & inibidores , Receptores de Tromboxanos , Tromboxano-A Sintase/antagonistas & inibidores , Ticlopidina/farmacologia , Varfarina/farmacologia
13.
Eur J Obstet Gynecol Reprod Biol ; 36(1-2): 185-95, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2114327

RESUMO

Both lupus anticoagulant and anticardiolipin antibody are groups of antiphospholipid antibodies associated with high frequency of thrombosis, fetal loss and thrombocytopenia. The hall marks of their identification is the prolongation of phospholipid-dependant coagulation tests. Much is written in literature about the successful management of lupus anticoagulant during pregnancy, via corticosteroid and acetyl salicylic acid (Aspirin) therapy; however, up to now only little has been mentioned about maternal and fetal complications associating lupus anticoagulant and its management. Here we present three cases with significant complications among patients with lupus anticoagulant managed in Sint Augustinus Hospital over the last 3 years. These complications were secondary to antiphospholipid syndrome or to therapy. Maternal complications included gastritis, atrophy of quadriceps muscle, resistant premature contractions and pre-eclampsia. One of our patients developed small lymphocytic lymphoma 1 year after her last labour. Fetal complications included: prematurity, suprarenal insufficiency (temporary) and delayed neuromuscular development found at the 2 year follow-up. As far as we know, some of these complications have never been mentioned in literature.


Assuntos
Fatores de Coagulação Sanguínea/imunologia , Complicações na Gravidez , Adulto , Aspirina/efeitos adversos , Aspirina/farmacologia , Autoanticorpos/fisiologia , Fatores de Coagulação Sanguínea/metabolismo , Cardiolipinas/imunologia , Quimioterapia Combinada , Feminino , Morte Fetal/etiologia , Gastrite/etiologia , Humanos , Indometacina/farmacologia , Leucemia Linfocítica Crônica de Células B/etiologia , Inibidor de Coagulação do Lúpus , Trabalho de Parto Prematuro/tratamento farmacológico , Trabalho de Parto Prematuro/etiologia , Prednisona/efeitos adversos , Prednisona/farmacologia , Gravidez , Ritodrina/farmacologia , Trombocitopenia/etiologia , Trombose/etiologia
14.
J Parasitol ; 64(3): 411-25, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-660379

RESUMO

The time-related topographical changes in mature cysticerci of Taenia taeniaformis induced after medication of infected mice with 250 ppm of mebendazole are described. The changes included the gradual disappearance of microtriches and progressive degeneration of the tegment resulting in an irregular surface with grooves, holes, and craterlike structures. Host cells adhered to the altered areas and the number of these cells increased when more severe changes became apparent. Finally the necrotized cysticerci, which lost their tegument completely, were almost entirely covered with adhesive host cells. A difference in the time sequence of the reported changes occurred between the scolex, the pseudoproglottids, and the bladder. This difference in susceptibility towards the drug between the three parts of the parasite in relation to the morphology of their microtrichous covering is discussed.


Assuntos
Benzimidazóis/farmacologia , Cysticercus/efeitos dos fármacos , Mebendazol/farmacologia , Taenia/efeitos dos fármacos , Animais , Cisticercose/tratamento farmacológico , Cisticercose/parasitologia , Cysticercus/ultraestrutura , Relação Dose-Resposta a Droga , Camundongos , Microscopia Eletrônica de Varredura
15.
J Parasitol ; 61(5): 830-43, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1185423

RESUMO

The progressive micromorphological changes in Taenia taeniaeformis cysticerci, induced by a single parenteral treatment of the infected mice with mebendazole, are described. The time-related alterations concerned the tegument and tegumental cells and were successively: disappearance of microtubules, accumulation of secretory substances in the Golgi areas, decrease in number to complete loss of microtriches, "ballooning" of all tegumental cells with subsequent burst, vacuolization and degeneration of the tegument, and finally necrosis of the pseudoproglottids. Similar but less pronounced injuries were seen in the scolices, although microtubules disappeared as early as in the pseudoproglottids. Microtubules from the host tissues remained intact. The meaning of the apparent primary interference of mebendazole with the microtubular system in relation to the subsequently observed death of the cysticercoids is discussed.


Assuntos
Benzimidazóis/farmacologia , Cysticercus/efeitos dos fármacos , Mebendazol/farmacologia , Taenia/efeitos dos fármacos , Animais , Gatos , Cisticercose/tratamento farmacológico , Cisticercose/parasitologia , Cysticercus/ultraestrutura , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/ultraestrutura , Larva/efeitos dos fármacos , Larva/ultraestrutura , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Mebendazol/uso terapêutico , Camundongos , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Fagocitose , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
16.
J Parasitol ; 74(6): 939-49, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3193333

RESUMO

A single 5-mg/kg oral dose of diclazuril affected both the asexual and sexual development of Eimeria tenella in experimentally inoculated chickens. In second-generation schizonts, early growth and nuclear divisions progressed normally, but a marked inhibition of merozoite formation was observed. Exogenesis of merozoites was largely prevented, whereas production of micronemes, amylopectin granules, and dense bodies and the formation of rhoptries, conoid, and pellicle continued. All these subcellular organelles accumulated, together with differentiated nuclei, within the main cytoplasmic mass. In the end, complete necrosis of the schizonts occurred. In macrogamonts, dilation of the rough endoplasmic reticulum around type II wall-forming bodies, fusion of type II wall-forming body contents, disturbance of the normal parallel arrangement of rough endoplasmic reticulum, and disruption of row formation of amylopectin granules became evident. In the microgamonts, normal evagination of microgametes was prevented; the flagellar complex formed within the main cytoplasmic mass and the differentiated nuclei remained present within the parasite body. The macro- and microgamonts also ended up in a stage of complete necrosis. These data indicate that diclazuril treatment primarily affects the normal differentiation of the respective endogenous stages during parasite development. This leads to complete degeneration of schizonts and gamonts indicating the lethal effect of this new anticoccidial compound.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Nitrilas/farmacologia , Doenças das Aves Domésticas/parasitologia , Triazinas/farmacologia , Animais , Núcleo Celular/ultraestrutura , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Coccidiostáticos/uso terapêutico , Citoplasma/ultraestrutura , Eimeria/crescimento & desenvolvimento , Eimeria/ultraestrutura , Microscopia Eletrônica , Nitrilas/uso terapêutico , Doenças das Aves Domésticas/tratamento farmacológico , Triazinas/uso terapêutico
17.
J Parasitol ; 67(5): 709-12, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7299582

RESUMO

The ultrastructural changes induced in hydatid cysts from lungs of sheep after medication with one or two courses of mebendazole (Ovitelmin), each lasting 3 wk, are described. The hydatid germinal membrane tissue collected from the treated sheep showed complete degeneration of the tegumental and subtegumental structures and minor degree of calcification. Lung hydatid cysts of the untreated sheep presented normal ultrastructural configurations.


Assuntos
Benzimidazóis/farmacologia , Equinococose Hepática/veterinária , Equinococose Pulmonar/veterinária , Mebendazol/farmacologia , Doenças dos Ovinos/parasitologia , Animais , Equinococose Hepática/parasitologia , Equinococose Pulmonar/parasitologia , Echinococcus/ultraestrutura , Feminino , Ovinos
18.
J Comp Pathol ; 95(1): 45-55, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3973110

RESUMO

Campylobacter-like bacteria were demonstrated in the neoplastic cells in 15 of 17 naturally occurring endophytic adenocarcinomas of the ascending colon in Wistar rats. These bacteria were also present in the cytoplasm in metastases in the regional lymph nodes. The microorganisms penetrated the epithelial layer and their presence was associated with a chronic productive inflammatory reaction. A possible causal association of Campylobacter-like organisms in carcinoma of the colon in man and in the Wistar rat is discussed.


Assuntos
Adenocarcinoma/etiologia , Infecções por Campylobacter/complicações , Campylobacter/isolamento & purificação , Neoplasias do Colo/etiologia , Citoplasma/microbiologia , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Animais , Colo/microbiologia , Neoplasias do Colo/microbiologia , Neoplasias do Colo/patologia , Metástase Linfática/microbiologia , Ratos , Ratos Endogâmicos
19.
Neuroscience ; 244: 77-89, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23583762

RESUMO

Besides its prominent role in angiogenesis, the vascular endothelial growth factor (VEGF) also exerts important protective effects on neurons. In particular, mice expressing reduced levels of VEGF suffer from late-onset motor neuron degeneration, whereas VEGF delivery significantly delays motor neuron death in ALS mouse models, at least partly through neuroprotective effects. Additionally, VEGF protects dorsal root ganglion (DRG) neurons against paclitaxel-induced neurotoxicity. Here, we demonstrate that VEGF also protects DRG neurons against hyperglycemia-induced neuronal stress as a model of diabetes-induced peripheral neuropathy. Specifically, VEGF decreased expression of the stress-related gene activating transcription factor 3 (ATF3) in DRG neurons isolated from streptozotocin-induced diabetic mice (ex vivo) and in isolated DRG neurons exposed to high glucose concentrations (in vitro). In vivo, local VEGF application also protected against paclitaxel- and diabetes-induced neuropathies without causing side effects. A small synthetic VEGF mimicking pentadecapeptide (QK) exerted similar effects on DRG cultures: the peptide reduced ATF3 expression in vitro and ex vivo in paclitaxel- and hyperglycemia-induced models of neuropathy to a similar extent as the full-length recombinant VEGF protein. By using transgenic mice selectively overexpressing the VEGF receptor 2 in postnatal neurons, these neuroprotective effects were shown to be mediated through VEGF receptor 2. Overall, these results underscore the potential of VEGF and VEGF-derived peptides for the treatment of peripheral neuropathies.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Avaliação Pré-Clínica de Medicamentos , Gânglios Espinais/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/farmacologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Gânglios Espinais/metabolismo , Glucose/antagonistas & inibidores , Glucose/toxicidade , Masculino , Camundongos , Camundongos Transgênicos , Fármacos Neuroprotetores/uso terapêutico , Paclitaxel/antagonistas & inibidores , Paclitaxel/toxicidade , Fragmentos de Peptídeos/uso terapêutico , Ratos , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
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