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1.
Stem Cells Int ; 2015: 583984, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26064137

RESUMO

MSCs derived from the umbilical cord tissue, termed UCX, were investigated for their immunomodulatory properties and compared to bone marrow-derived MSCs (BM-MSCs), the gold-standard in immunotherapy. Immunogenicity and immunosuppression were assessed by mixed lymphocyte reactions, suppression of lymphocyte proliferation and induction of regulatory T cells. Results showed that UCX were less immunogenic and showed higher immunosuppression activity than BM-MSCs. Further, UCX did not need prior activation or priming to exert their immunomodulatory effects. This was further corroborated in vivo in a model of acute inflammation. To elucidate the potency differences observed between UCX and BM-MSCs, gene expression related to immune modulation was analysed in both cell types. Several gene expression profile differences were found between UCX and BM-MSCs, namely decreased expression of HLA-DRA, HO-1, IGFBP1, 4 and 6, ILR1, IL6R and PTGES and increased expression of CD200, CD273, CD274, IL1B, IL-8, LIF and TGFB2. The latter were confirmed at the protein expression level. Overall, these results show that UCX seem to be naturally more potent immunosuppressors and less immunogenic than BM-MSCs. We propose that these differences may be due to increased levels of immunomodulatory surface proteins such as CD200, CD273, CD274 and cytokines such as IL1ß, IL-8, LIF and TGFß2.

2.
Endocrine ; 49(3): 809-19, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25586874

RESUMO

We analyzed the effects of chemically blocking type 1 muscarinic receptors (M1R) on either the left or right ovary on ovulation rate, number of ova shed and steroid hormones levels. M1R were unilaterally blocked in ovary with the M1R selective antagonist pirenzepine (PZP). PZP was delivered into the bursa ovarica of the left or right ovary of adult rats at 13:00 h on proestrus day. PZP treatment in the left but not in the right ovary blocked ovulation. PZP did not modify the number of ova shed, nor progesterone or 17ß-estradiol serum levels. The surge of luteinizing hormone levels was diminished while that of follicle-stimulating hormone did not change in animals treated with PZP in the left ovary. Interestingly, treatment with either synthetic luteinizing hormone-releasing hormone or human chorionic gonadotropin 1 h after PZP administration in the left ovary restored ovulation in both ovaries. The presence of M1R protein in the theca cells of the ovarian follicles as well as in cells of the corpus luteum was detected on proestrus day. These results suggest that M1R activation in the left ovary is required for pre-ovulatory gonadotropin-releasing hormone (GnRH) secretion and ovulation. Furthermore, these results also suggest that M1R in the left ovary might be regulating ovulation asymmetrically through a stimulatory neural signal relayed to the hypothalamus via the vagus nerve to induce the GnRH secretion which then triggers ovulation.


Assuntos
Ovário/metabolismo , Ovulação/fisiologia , Proestro/fisiologia , Receptor Muscarínico M1/metabolismo , Animais , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Hipotálamo/metabolismo , Hormônio Luteinizante/sangue , Antagonistas Muscarínicos/farmacologia , Folículo Ovariano/metabolismo , Ovulação/efeitos dos fármacos , Pirenzepina/farmacologia , Proestro/efeitos dos fármacos , Progesterona/sangue , Ratos , Receptor Muscarínico M1/efeitos dos fármacos , Células Tecais , Vagotomia
3.
Transplant Proc ; 46(6): 1839-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25131049

RESUMO

Intestinal failure is a multifaceted condition that may require high-complexity treatment and a multidisciplinary program, including home parenteral nutrition therapy (HPNT) and intestinal transplantation. In this article, we profile a Brazilian single-center experience with 128 cases of HTPN followed for the last 30 years and appraise the referral for potential intestinal and multivisceral transplantation.


Assuntos
Intestinos/transplante , Nutrição Parenteral no Domicílio/métodos , Cuidados Pós-Operatórios/métodos , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta , Adulto , Brasil , Feminino , Humanos , Masculino , Estudos Retrospectivos
4.
J Biomed Nanotechnol ; 10(12): 3647-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26000378

RESUMO

Main-stay in treatment of leishmaniasis relies on chemotherapy but none of the current drugs combines high activity and low toxicity at affordable costs. Dinitroanilines are a new class of drugs with proved in vitro antileishmanial activity. However the development of their pharmaceutical formulations has been compromised by low water solubility and low accumulation in diseased organs. These limitations can be overcome by incorporation in lipid-based nanoformulations such as liposomes and solid lipid nanoparticles. In previous work this strategy was already followed with the incorporation of a dinitroaniline, oryzalin, resulting in the improvement of the biodistribution profile. The present work aims at demonstrating the in vitro and in vivo therapeutic activity of these oryzalin nanoformulations, and establishing a systematic comparison of both systems. After oryzalin incorporation suitable physicochemical properties for parenteral administration were obtained. Nanoformulations revealed reduced cytotoxicity and haemolytic activity when compared with free-oryzalin, while retaining the in vitro intracellular activity. Therapeutic activity, assessed in a murine model of visceral leishmaniasis, was evaluated in terms of number of administrations, dose-response and influence of the lipid excipient. Results demonstrate the superiority of both oryzalin nanoformulations on the reduction of parasitic burden in liver and spleen as compared to the control group (84 to 91%) and similar to Glucantime. A strong reduction in ED50 values (3 to 65 fold) as compared to free-oryzalin was also obtained, depending on the organ and nanoformulation used. Both oryzalin nanoformulations are potential candidates as therapeutic agents against visceral leishmaniasis.


Assuntos
Dinitrobenzenos/administração & dosagem , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Leishmaniose/patologia , Lipídeos/química , Lipossomos/química , Nanocápsulas/química , Sulfanilamidas/administração & dosagem , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/química , Difusão , Dinitrobenzenos/química , Leishmania/citologia , Leishmania/fisiologia , Masculino , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Sulfanilamidas/química , Resultado do Tratamento
5.
Neurol Sci ; 34(5): 741-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22661103

RESUMO

A number of experimental and clinical reports suggest the involvement of oxidative stress in pathophysiology of epilepsy. Topiramate, a new antiepileptic drug, induces antioxidant effect in epileptic animals. However, to date, no further studies appear to be carried out in order to demonstrate the ability of topiramate to act as antioxidant. Therefore, the objective of this work was to evaluate the in vitro superoxide (O2(·-)), hydroxyl radical (OH·), hypochlorous acid (HOCl), hydrogen peroxide (H2O2), singlet oxygen ((1)O2) and peroxynitrite (ONOO(-)) scavenging capacity of topiramate in comparison with reference compounds. In addition, we investigated the possible antitumour activity of this compound in some cancer cell lines. Topiramate displays a scavenging capacity compared to the reference compound, with the exception of ONOO(-), although it was less efficient than nordihydroguaiaretic acid, dimethylthiourea, ascorbic acid, sodium pyruvate and glutathione for O2(·-), OH·, HOCl, H2O2 and (1)O2(P < 0.0001), respectively, and not induced significant growth inhibition in cancer cell lines. The direct antioxidant properties of topiramate could explain the neuroprotective effects attributed to this compound and suggest its use as chemopreventive agent in a future.


Assuntos
Antioxidantes/farmacologia , Sequestradores de Radicais Livres/metabolismo , Frutose/análogos & derivados , Linhagem Celular Tumoral/classificação , Linhagem Celular Tumoral/patologia , Relação Dose-Resposta a Droga , Frutose/farmacologia , Humanos , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Topiramato
6.
Rev. bras. plantas med ; 15(4,supl.1): 727-733, 2013. tab
Artigo em Inglês | LILACS | ID: lil-700011

RESUMO

In banana, fruit rot is incited by Colletotrichum musae which has been the most serious post-harvest disease of immature and mature fruit. The usual control by fungicides prohibited in many countries reduces their commercial value. Therefore, two experiments were conducted to evaluate the antimicrobial activity of alternative products to the synthetic fungicides. First, berries naturally infected by anthracnose were immersed into Azadirachta indica and citric extracts at 2 and 4% (v/v) for 3 minutes and stored for 11 days under environmental conditions. Next, other berries were immersed into essential oil emulsions of Allium sativum, Copaifera langsdorfii, Cinnamomum zeylanicum and Eugenia caryophyllata at 5% for 3 minutes but stored for 11 days. Berries immersed into distilled water were used as control-treatments. The percentage of disease incidence observed in the control-treatment was similar to the ones observed in the extract of A. indica at 2%. The control-treatment showed disease severity of 75.13% and the percentage of disease control was 20.85%. Fruit immersed into distilled water presented less effectiveness than the ones immersed into citric extracts, which promoted the highest effectiveness. Citric extract at 4% was the most efficient treatment because the disease incidence was 19.44%, the disease severity was 9.34% and the disease control was 90.16%. Less severity and, consequently, more disease control were achieved by immersing the berries into the emulsion of essential oil of A. sativum, followed by treatments with C. langsdorfii, E. caryophyllata and C. zeylanicum.


Em pós-colheita, a podridão dos frutos causada por Colletotrichum musae é a doença mais importante da banana (Musa spp.), sendo presente em frutos verdes e maduros, tornando o produto pouco apresentável e inadequado à comercialização. Considerando-se os efeitos prejudiciais à saúde do tradicional método químico de controle e a proibição da utilização de fungicidas em muitos países, objetivou-se no presente trabalho avaliar bioprodutos com atividade antimicrobiana, considerados alternativos para o controle de antracnose em banana em pós-colheita. Os experimentos foram realizados com frutos de banana naturalmente infectados com Colletotrichum musae, submetidos à imersã, em extratos da planta Azadirachta indica e extratos cítricos (Ecolife), nas concentrações de 2 e 4% (v/v), permanecendo por 11 dias em condições ambientes. A emulsão composta de óleos essenciais das plantas Allium sativum, Copaifera langsdorfii, Cinnamomum zeylanicum e Eugenia caryophyllata também foi avaliada quanto a sua eficácia no controle do patógeno, permanecendo em condição ambiente por 11 dias. Frutos tratados com água destilada constituíram o tratamento controle. Os resultados obtidos demonstraram que frutos submetidos ao extrato aquoso de A. indica na concentração de 2% (88,89%) não diferiu do tratamento controle (100% de incidência da doença). O extrato cítrico a 4% promoveu percentuais de incidência, severidade e controle de 19,44; 9,34 e 90,16%, respectivamente, sendo o mais eficiente. Menor percentual de severidade e o maior percentual de controle da doença nos frutos foram proporcionados pela emulsão óleos essenciais de A. sativum, seguidos pelos tratamentos com C. langsdorfii, E. caryophyllata e C. zeylanicum.


Assuntos
Extratos Vegetais/análise , Musa/classificação , Óleos Voláteis/isolamento & purificação , Colletotrichum/isolamento & purificação
7.
Eur J Pharm Sci ; 45(4): 442-50, 2012 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-21983568

RESUMO

Oryzalin is a dinitroaniline drug that has attracted recent interest for the treatment of leishmaniasis. Its use as an antiparasitic therapeutic agent is limited by the low water solubility associated with an in vivo rapid clearance, leading to the administration of larger and possibly toxic doses in in vivo studies, and the use of solvents that may lead to undesirable side effects. In the present work oryzalin-containing lipid nanoparticles were produced by a emulsion-solvent evaporation technique using a composition suitable for parenteral administration, i.e., tripalmitin (solid lipid) and a complex mixture of three emulsifying agents (soya lecithin, Tween® 20 and sodium deoxycholate). Physicochemical characterization included the determination of mean particle size, polydispersity index, zeta potential, encapsulation efficiency and DSC studies. Final formulations revealed values of <140 nm (PI<0.2) and zeta potential of ≈-35 mV, as well as encapsulation efficiency >75%. The effects of various processing parameters, such as lipid and surfactant and composition and concentration, as well as the stability during the harsh procedures of autoclaving (121°C/15 min) and freeze-drying were also evaluated. Formulations revealed to be stable throughout freeze-drying and moist-heath sterilization without significant variations on physicochemical properties and no significant oryzalin losses. The use of a complex surfactant mixture proved crucial for preserving formulation stability. Particularly, lecithin appears as a key component in the stabilization of tripalmitin-based oryzalin-containing lipid nanoparticles. Finally, cell viability studies demonstrated that the incorporation of oryzalin in nanoparticles decreases cytotoxicity, thus suggesting this strategy may improve tolerability and therapeutic index of dinitroanilines.


Assuntos
Antiprotozoários/química , Dinitrobenzenos/química , Nanopartículas/química , Polissorbatos/química , Sulfanilamidas/química , Antiprotozoários/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácido Desoxicólico/química , Dinitrobenzenos/farmacologia , Estabilidade de Medicamentos , Humanos , Lecitinas/química , Leishmaniose , Tamanho da Partícula , Polissorbatos/farmacologia , Sulfanilamidas/farmacologia , Propriedades de Superfície , Tensoativos/química , Triglicerídeos/química
8.
Rev. bras. plantas med ; 14(3): 439-445, 2012. graf, tab
Artigo em Português | LILACS | ID: lil-658122

RESUMO

Este trabalho verificou o efeito dos óleos essenciais (OE) extraídos de Eremanthus erythropappus (candeia), Cymbopogon martinii (palmarosa) e de Rosmarinus officinalis (alecrim) no crescimento micelial de alguns fitopatógenos fúngicos e no tratamento de sementes de milho, soja e feijão. No teste in vitro, alíquotas de 20, 40, 60, 100, 200, 500 e 1000 μL de cada um dos óleos essenciais foram distribuídas na superfície do meio de cultura. Posteriormente, discos de meio de cultura com micélio de Alternaria carthami, Alternaria sp. e Rhizoctonia solani foram transferidos para o centro de cada placa. O crescimento foi mensurado e calculada a taxa de inibição do crescimento micelial (ICM). Para verificar o efeito dos OE na germinação das sementes utilizou-se a aplicação deles por fumigação. Foi avaliada a percentagem de sementes germinadas e a incidência de patógenos nas sementes. Sobre o crescimento micelial, o óleo de palmarosa inibiu completamente todos os patógenos fúngicos, independentemente da concentração. Já os óleos de candeia e alecrim foram melhores quando foram adicionadas alíquotas superiores a 200 μL. Os óleos influenciaram diferentemente a germinação e a sanidade das sementes de milho, soja e feijão.


This study aimed to verify the effect of essential oils (EO) extracted from Eremanthus erythropappus ("candeia") Cymbopogon martinii ("palmarosa") and Rosmarinus officinalis (rosemary) on the mycelial growth of some fungal phytopathogens, as well as on the treatment of corn, soybean and bean seeds. In the in vitro test, aliquots of 20, 40, 60, 100, 200, 500 and 1000 μL of each essential oil were distributed on the surface of the culture medium. Then, discs of culture medium with mycelium of Alternaria carthami, Alternaria sp and Rhizoctonia solani were transferred to the center of each plate. Growth was measured and the mycelial growth inhibition rate (MGI) was calculated. To verify the effect of EO on seed germination, application of oils was by means of fumigation. Percentage of germinated seeds and their incidence of pathogens were evaluated. For mycelial growth, "palmarosa" oil completely inhibited all fungal pathogens, regardless of the concentration. On the other hand, "candeia" and rosemary oils were better when aliquots higher than 200 μL were added. The oils differently influenced the germination and health of corn, soybean and bean seeds.


Assuntos
Doenças das Plantas/prevenção & controle , Sementes/crescimento & desenvolvimento , Óleos Voláteis/efeitos adversos , Anti-Infecciosos/análise
9.
Arq. Inst. Biol. (Online) ; 77(4): 677-683, out.-dez. 2010. graf
Artigo em Português | VETINDEX, LILACS | ID: biblio-1395475

RESUMO

O trabalho foi desenvolvido para verificar o efeito do óleo essencial e do extrato bruto de alfavaca-cravo (Ocimum gratissimum), coletado nas quatro estações do ano, no crescimento micelial in vitro dos fungos Rhizoctonia solani, Sclerotium rolfsii, Phytophthora sp. e Alternaria alternata. Para avaliar o efeito do óleo essencial no crescimento micelial dos fungos, alíquotas de 20 ?L, 40 ?L e 60 ?L de óleo esterilizado foram distribuídas na superfície de meio BDA (batata-dextrose-ágar) antes da repicagem dos fungos. O extrato bruto aquoso (EBA) foi filtrado e incorporado em BDA nas concentrações de 1%, 5%, 10%, 15%, 20%, 25% e 50%. Os resultados indicaram que houve inibição total do crescimento micelial dos fungos nas diferentes alíquotas de óleo essencial. O EBA das plantas colhidas no outono proporcionou os melhores resultados, sendo que nesta estação do ano o EBA na concentração de 5% foi suficiente para promover 100% de inibição do crescimento micelial dos fitopatógenos A. alternata e S. rolfsii.


The present >work aimed to evaluate the effects of the essential oil and crude extract of wild basil (Ocimum gratissimum), harvested in different seasons, on the in vitro mycelia growth of Rhizoctonia solani, Sclerotium rolfsii, Phytophthora sp. and Alternaria alternata. To evaluate the effect of the essential oil, sterilized oil aliquots of 20 ?L, 40 ?L and 60 ?L were distributed on the surface of potato-dextroseagar (PDA). The aqueous crude extracts (ACE) were filtrated and incorporated in PDA at 1%, 5%, 10%, 15%, 20%, 25% and 50%. The results showed total inhibition of mycelial growth in the different aliquots of essential oil. The ACE collected from plants in autumn had better results; in this season the ACE at 5% was enough to provide 100% of mycelia growth inhibition of A. alternata and S. rolfsii.


Assuntos
Doenças das Plantas/prevenção & controle , Plantas Medicinais , Óleos Voláteis/uso terapêutico , Extratos Vegetais/uso terapêutico , Ocimum
10.
Rev. bras. plantas med ; 12(1): 57-61, jan.-mar. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-578935

RESUMO

A helmintosporiose, causada pelo fungo Exserohilum turcicum, é uma das principais doenças do milho-pipoca cultivado no Brasil. Devido às características da cultura, como porte da planta, extensão da área de plantio e rentabilidade econômica, o emprego de resistência genética e controle químico têm sido as principais formas de controle da doença. O emprego de agrotóxicos na agricultura tem levado riscos à saúde humana e freqüentes danos ao meio ambiente. Assim, na busca de métodos alternativos para o controle da helmintosporiose foi avaliado o efeito fungitóxico dos extratos vegetais das plantas Achillea milefollium (mil-folhas), Cymbopogon citratus (capim-limão), Artemisia camphorata (cânfora) e Rosmarinus officinalis (alecrim) no crescimento micelial de E. turcicum, em dois meios de cultura (BDA - batata-dextrose-ágar; e LCH - lactose caseína hidrolisada). Os extratos de alecrim e cânfora foram os que apresentaram maior inibição do crescimento micelial nos dois meios de cultura, enquanto que os extratos de mil-folhas e capim limão estimularam o crescimento micelial em meio LCH.


Helminthosporiose is caused by the fungus Exserohilum turcicum and represents one of the main diseases in popcorn grown in Brazil. Due to its characteristics, such as plant size, planting area extension and economic profitability, the use of genetic resistance and chemical control has constituted the main procedure against such disease. The use of pesticides in agriculture has resulted in risks to the human health and frequent damages to the environment. Thus, the fungitoxic effect of plant extracts of Achillea millefolium (yarrow), Cymbopogon citratus (lemon grass), Artemisia camphorata (camphor) and Rosmarinus officinalis (rosemary) on the mycelial growth of E. turcicum was evaluated by using two culture media (PDA - potato dextrose agar, and LCH - lactose-casein hydrolysate) in order to set alternative methods for controlling helminthosporiose. Rosemary and camphor extracts led to higher mycelial growth inhibition in both culture media, whereas yarrow and lemon grass extracts stimulated mycelial growth in LCH medium.


Assuntos
Helmintos/isolamento & purificação , Técnicas In Vitro , Micotoxinas/toxicidade , Achillea , Cânfora , Cymbopogon , Extratos Vegetais , Rosmarinus , Zea mays
11.
Bioorg Med Chem ; 18(1): 274-81, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19926293

RESUMO

A series of new analogues of trifluralin (TFL) were synthesized and characterized in view of changing the unfavorable properties that limits its use as antileishmanial agent. Some of the TFL analogues display more activity than a standard drug (miltefosine) against the promastigote forms of Leishmania infantum and Leishmania donovani and the intracellular form (THP-1 infected with L. infantum). All analogues showed a clear advantage over miltefosine, as they are not hemolytic. Some analogues can conjugate these characteristics with reduced cell toxicity and improved intracellular activity.


Assuntos
Antiprotozoários/química , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Trifluralina/química , Trifluralina/farmacologia , Antiprotozoários/síntese química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Leishmania donovani/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Trifluralina/síntese química
12.
Curr Top Med Chem ; 8(7): 579-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18473884

RESUMO

The clinical management of tuberculosis and other mycobacterial diseases with antimycobacterial chemotherapy remains a difficult task. The classical treatment protocols are long-lasting; the drugs reach mycobacteria-infected macrophages in low amounts and/or do not persist long enough to develop the desired antimycobacterial effect; and the available agents induce severe toxic effects. Nanotechnology has provided a huge improvement to pharmacology through the designing of drug delivery systems able to target phagocytic cells infected by intracellular pathogens, such as mycobacteria. Liposomes and nanoparticles of polymeric nature represent two of the most efficient drug carrier systems that after in vivo administration are endocytosed by phagocytic cells and then release the carried agents into these cells. This article reviews the relevant publications describing the effectiveness of the association of antimycobacterial agents with liposomes or nanoparticles for the treatment of mycobacterioses, particularly for Mycobacterium tuberculosis and M. avium infections. The increased therapeutic index of antimycobacterial drugs; the reduction of dosing frequency; and the improvement of solubility of hydrophobic agents, allowing the administration of higher doses, have been demonstrated in experimental infections. These advantages may lead to new therapeutic protocols that will improve patient compliance and, consequently, lead to a more successful control of mycobacterial infections. The potential therapeutic advantages resulting from the use of non-invasive administration routes for nanoparticulate systems are also discussed.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Sistemas de Liberação de Medicamentos , Infecções por Mycobacterium/tratamento farmacológico , Antibacterianos/química , Humanos , Lipossomos , Infecções por Mycobacterium/epidemiologia , Infecções por Mycobacterium/etiologia , Nanopartículas
13.
Int J Antimicrob Agents ; 31(1): 37-45, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18006283

RESUMO

Tuberculosis (TB) is a leading cause of death amongst infectious diseases. The low permeation of antimycobacterial agents and their difficult access to infected macrophages necessitate long-term use of high drug doses. Liposomes preferentially accumulate in macrophages, increasing the efficacy of antibiotics against intracellular parasites. In the present work, several rifabutin (RFB) liposomal formulations were developed and characterised and their in vivo profile was compared with free RFB following intravenous administration. With the RFB liposomal formulations tested, higher concentrations of the antibiotic were achieved in liver, spleen and lungs 24h post administration compared with free RFB. The concentration of RFB in these organs was dependent on the rigidity of liposomal lipids. The liposomal RFB formulation prepared with dipalmitoyl phosphatidylcholine:dipalmitoyl phosphatidylglycerol (DPPC:DPPG) was the most effective and was selected for biological evaluation in a mouse model of disseminated TB. Compared with mice treated with free RFB, mice treated with the DPPC:DPPG RFB formulation exhibited lower bacterial loads in the spleen (5.53 log(10) vs. 5.18 log(10)) and liver (5.79 log(10) vs. 5.41 log(10)). In the lung, the level of pathology was lower in mice treated with encapsulated RFB. These results suggest that liposomal RFB is a promising approach for the treatment of extrapulmonary TB in human immunodeficiency virus co-infected patients.


Assuntos
Antituberculosos/administração & dosagem , Rifabutina/administração & dosagem , Tuberculose/tratamento farmacológico , Animais , Antituberculosos/farmacocinética , Antituberculosos/uso terapêutico , Química Farmacêutica , Lipossomos , Fígado/química , Fígado/microbiologia , Pulmão/química , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Rifabutina/farmacocinética , Rifabutina/uso terapêutico , Baço/química , Baço/microbiologia , Fatores de Tempo
14.
Vet J ; 178(1): 133-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17855131

RESUMO

Liposomes are used as carriers to deliver drugs and to treat diseases where infection is localised in the mononuclear phagocyte system cells, as is the case of leishmaniosis. Trifluralin is a dinitroaniline with proved anti-Leishmania activity in vitro. The efficacy of liposomal trifluralin (LIP/TFL) was studied in the treatment of experimental canine leishmaniosis through quantification of parasite burden using the limiting dilution assay, follow-up of anti-Leishmania antibodies by indirect fluorescent immunoassay and cytokine expression by Reverse Transcriptase-PCR, in the bone marrow, lymph nodes, skin and peripheral blood mononuclear cells in 5 female beagle dogs. After treatment, dogs showed a general remission of clinical signs related to parasite burden reduction and Th1 cytokine mRNA expression, but there was no significant decrease in antibody levels. Alternative treatment schemes with LIP/TFL are necessary to achieve optimal results.


Assuntos
Doenças do Cão/tratamento farmacológico , Leishmaniose Cutânea/veterinária , Trifluralina/uso terapêutico , Animais , Anticorpos Antiprotozoários/sangue , Citocinas/metabolismo , Doenças do Cão/patologia , Cães , Regulação da Expressão Gênica/fisiologia , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Th1/metabolismo
15.
Eur J Pharm Sci ; 26(3-4): 307-17, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16129587

RESUMO

To understand better the wide-spread pharmaceutical use of non-ionic surfactant Tween 80 (TW), the colloidal properties of the surfactant alone and in combinations with the common phospholipid, phosphatidylcholine (PC), were studied. Static and dynamic light scattering revealed that TW solubilises PC at TW/PC approximately 2.75/1 mol/mol and that TW micelle disintegration occurs on time-scale of 2.5 min, independent of amphipath concentration. This is up to nearly 300-times faster than the TW caused dissolution of PC containing unilamellar vesicles. The apparent dissolution time of TW/PC mixed aggregates, in contrast, decelerates from >700 min to <5 min upon increasing starting total amphipath concentration, with thermal activation energy > or =24 (< or =80) kJ mol(-1). The aggregate dissolution rate in highly concentrated TW/PC suspensions reflects the dissolved polysorbate-aggregate exchange rate (approximately 6.7 x 10(-3)s(-1)) rather than TW flip-flop rate across a bilayer (>0.2 min(-1)). PC solubilisation proceeds linearly with the square-root of time, and is kinetically governed by the speed of surfactant diffusion through the bulk (D approximately 2.8 x 10(-11)m2 s(-1)). Creation of small Tween-phosphatidylcholine mixed micelles is typically preceded by pre-solubilisation structures, first in the form of deformable, strongly fluctuating, bilayer vesicles and then of elongated, presumably thread-like, mixed micelles. TW/PC mixed micelles become smaller with growing surfactant/lipid molar ratio, whereas TW/PC mixed vesicles become more and more leaky with increasing surfactant concentration. Our results highlight the molecular and kinetic aspects of polysorbate-membrane interactions and provide a rationale for the popularity of Tween surfactants in pharmaceutical products: such surfactants can solubilise fatty molecules and bilayer membranes but need quite a long time for this, which is available in pharmaceutical preparations but normally not in vivo; this makes Tweens relatively efficient and safe. Furthermore, our data could help design better ultra-deformable mixed lipid-surfactant vesicles for the non-invasive transdermal drug delivery across the skin.


Assuntos
Glycine max , Fosfatidilcolinas/administração & dosagem , Polissorbatos/administração & dosagem , Bicamadas Lipídicas , Micelas , Permeabilidade , Solubilidade , Temperatura
16.
J Control Release ; 103(2): 419-34, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-15763624

RESUMO

The aim of this study was firstly to refine a rat model of arthritis, the adjuvant arthritis (AA) model, by studying the time course of the disease, introducing new evaluation methods such as haematological and biochemical parameters in order to identify the main stages of the disease. An optimisation of treatment schedule and evaluation criteria was developed. This refinement provided novel non-invasive anti-inflammatory treatment of the AA with SOD by using mixed lipid vesicles specially developed for transdermal delivery, Transfersomes (Tfs), this being the second major aim. The time course of AA includes a first stage: 1 day after the disease induction, the induced paw volume more than doubled and the paw circumference increased by approx. 50%. Two weeks later, another stage occurred where the disease shifted from the local arthritis form towards polyarthritis: an additional increase of volume and circumference of the induced and non-induced paws, occurred. The animals also started to loose weight around day 14 after the disease induction. Radiographic observable lesions increased correspondingly. Treatment of animals, started at day 1 after induction, by epicutaneous application of SOD-Tfs showed that 1 mg SOD/kg body weight is more efficient than 0.66 mg SOD /kg body weight. As a positive control, SOD liposomes intravenously injected were used for comparison and confirmed the biological efficiency of epicutaneously applied SOD in Tfs. SOD solution and empty Tfs epicutaneously applied exerted no effect. In addition, epicutaneous application of SOD-Tfs used prophylactically was able to suppress the induced rat paw oedema. Radiographic images showed less joint lesions in SOD-Tfs treated animals in comparison with control and placebo treated rats. It was shown for the first time that SOD incorporated into Tfs and applied onto a skin area not necessarily close to the inflamed tissue is able to promote non-invasive treatment of induced arthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Superóxido Dismutase/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Artrite Experimental/sangue , Artrite Experimental/diagnóstico por imagem , Ácido Ascórbico/sangue , Portadores de Fármacos/química , Extremidades/diagnóstico por imagem , Contagem de Leucócitos , Lipossomos , Masculino , Tamanho da Partícula , Radiografia , Ratos , Ratos Wistar , Compostos de Sulfidrila/sangue , Superóxido Dismutase/administração & dosagem , Superóxido Dismutase/química , Resultado do Tratamento
17.
Med Trop (Mars) ; 65(4): 343-5, 2005 Sep.
Artigo em Francês | MEDLINE | ID: mdl-16548486

RESUMO

Mini mental state tests (MMS) were administered to 227 adults over the age of 40 years living in an Ecuadorian urban Andean community known to be an endemic zone for Taenia solium taeniasis and cysticercosis. The overall prevalence of cognitive impairment was 8.4% (19/227). The prevalence of cognitive impairment was 23.5% (8 cases) in adults over 75 years (n=34). The Hachinski ischemic score for vascular dementia was abnormal in 4 of the 19 adults (21%) exhibiting cognitive impairment. This survey highlighted a high prevalence of dementia in comparison with industrialised countries. Parasitic encephalopathy that was present in one out of five persons in this Andean community could play a part in early damage of cognitive function.


Assuntos
Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/parasitologia , Doenças Endêmicas , Neurocisticercose/complicações , Neurocisticercose/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Equador/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Urbana
18.
Eur J Pharm Biopharm ; 58(3): 509-19, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15451525

RESUMO

Carriers for non-invasive administration of biologically important antioxidant enzymes Cu,Zn-superoxide dismutase (SOD) and catalase (CAT) were developed. Solubilisation and permeabilities of various soybean phosphatidylcholine/sodium cholate (SPC/NaChol) mixtures, mainly in the form of lipid bilayers, focussing on system properties relevant for non-invasive enzyme delivery were investigated in this work. Static and dynamic light scattering measurements gave information on the behaviour of the systems containing up to 40 mM NaChol and 30.6-1.2 mM SPC in the final suspension. The average size of such mixed aggregates was in the 100-200 nm range. Suspension turbidity decreased by 50% upon increasing nominal molar detergent/lipid ratio to NaChol/SPC = 7 and 1.25, in case of SPC = 1.2 and 19.6 mM, respectively. The effective NaChol/SPC molar ratio in bilayers saturated with the detergent was found to be: R(e)(sat) = 0.70 +/- 0.01; bilayer solubilisation point corresponded to R(e)(sol) = 0.97 +/- 0.02, independently of enzyme loading. Vesicles became very permeable to SOD when membrane bound NaChol concentration exceeded 13.7 mM, in case of total starting lipid concentration of 138 mM diluted to SPC = 19.6 mM. Specifically, we measured a 50% loss of SOD from the vesicles with an aggregate-associated molar detergent ratio NaChol/SPC approximately 0.7, which is near the saturation but well below the solubilisation limit. Calcein efflux from such vesicles was compared with SPC/NaChol/SOD mixed aggregates. Our results should contribute to the future design of vesicle mediated transdermal delivery of antioxidant enzymes.


Assuntos
Colatos/química , Sistemas de Liberação de Medicamentos/métodos , Fosfatidilcolinas/química , Proteínas/química , Colato de Sódio/química , Administração Cutânea , Colatos/administração & dosagem , Colatos/farmacocinética , Substâncias Macromoleculares/administração & dosagem , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacocinética , Permeabilidade/efeitos dos fármacos , Fosfatidilcolinas/administração & dosagem , Fosfatidilcolinas/farmacocinética , Proteínas/administração & dosagem , Proteínas/farmacocinética , Colato de Sódio/administração & dosagem , Colato de Sódio/farmacocinética , Solubilidade/efeitos dos fármacos
19.
J Ethnopharmacol ; 86(2-3): 213-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12738089

RESUMO

The mistletoe Psittacanthus calyculatus (Loranthaceae) is used in Mexican traditional medicine for the treatment of hypertension. In the present study the effects of a crude ethanolic extract of this mistletoe, on the vasomotor reactivity of superfused rat aortic rings (with or without a functional endothelium) were analyzed. Either in the absence or in the presence of L-NAME or indomethacin, the extract (12.5-800 microg/ml) had no effect on the basal tone of both types of rings. In phenylephrine-precontracted rings, low concentrations of the extract (up to 300 microg/ml) induced a small additional tension development in both types of rings; however, the tension increase was slightly larger in rings having an intact endothelium. At higher concentrations (400-800 microg/ml), the extract relaxed, concentration-dependently, phenylephrine-precontracted rings with an intact endothelium. This relaxation was completely reverted by the addition of L-NAME. When the extract was applied in the continuous presence of L-NAME to phenylephrine-precontracted rings, instead of a relaxation a marked additional tension development occurred. Indomethacin did not modify the relaxation induced by the extract. The results indicate that the ethanolic extract of this mistletoe induces, predominantly, an endothelium-dependent relaxation which seems to be mediated by the synthesis/release of nitric oxide.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Medicina Tradicional , Músculo Liso Vascular/efeitos dos fármacos , Folhas de Planta , Preparações de Plantas/farmacologia , Proteínas de Plantas , Toxinas Biológicas/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Masculino , México , NG-Nitroarginina Metil Éster/farmacologia , Fenilefrina/farmacologia , Preparações de Plantas/isolamento & purificação , Ratos , Ratos Wistar , Proteínas Inativadoras de Ribossomos Tipo 2 , Toxinas Biológicas/isolamento & purificação , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia
20.
Biochim Biophys Acta ; 1609(2): 211-7, 2003 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-12543383

RESUMO

Superoxide dismutase (SOD) was chemically modified by covalent linkage of fatty acid chains to the accessible epsilon-amino groups of the enzyme. This acylation method gave rise to a different enzyme entity (Ac-SOD) as evidenced by different physicochemical properties such as octanol/water partition coefficient and isoelectric point (pI) as compared to SOD. Ac-SOD was incorporated in conventional and long-circulating liposomes (LCL) and characterized in terms of incorporation efficiency, protein to lipid ratio (Prot/Lip), enzymatic activity retention and zeta potential. The observation that Ac-SOD liposomes present enzymatic activity on their external surface indicates that these formulations can act independent of rate and extent of enzyme release as required in case of SOD liposomes. The decrease of superficial charge of liposomal formulations containing Ac-SOD, as compared to SOD liposomes, may be related to the negatively charged enzyme molecules localized on the liposome surface. The comparative characterization of Ac-SOD and SOD liposomal formulations evidenced that the two enzyme forms differ substantially regarding their intraliposomal location: SOD tends to be localized in the internal aqueous spaces, whereas Ac-SOD is expected to be localized in the lipid bilayers of the liposomes, partially buried into the outer surface and exposed to the external medium. These liposomal structures with surface-exposed SOD were designated as Ac-SOD enzymosomes. The properties of these enzymosomes may influence the therapeutic effect, as the release of the enzyme from extravasated vesicles is no longer a necessary requirement for achieving dismutating activity within the inflamed target site.


Assuntos
Lipossomos/química , Superóxido Dismutase/química , Acilação , Aminas , Dimiristoilfosfatidilcolina , Desenho de Fármacos , Ponto Isoelétrico , Bicamadas Lipídicas/química , Peso Molecular , Tamanho da Partícula , Polietilenoglicóis , Temperatura
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