Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Braz. J. Pharm. Sci. (Online) ; 58: e20868, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420441

RESUMO

Abstract Intrauterine adhesions cause several gynecological problems. Althaea officinalis L. roots known as marshmallows contain polysaccharides (M.P.) which possess anti-inflammatory and anti-ulcerogenic activities also can form a bio-adhesive layer on damaged epithelial membranes prompting healing processes. Vaginal formulations of herbal origin are commonly applied to relieve cervico-uterine inflammation. Herein, we aim to develop and evaluate vaginal suppositories containing polysaccharides isolated from the A. officinalis root. Six formulations (four P.E.G.-based and two lipid-based suppositories containing 25% and 50% M.P.) met standard requirements, which were then subjected to qualitative and quantitative evaluation. All suppositories exhibited acceptable weights, hardness, content uniformity, melting point, and disintegration time, which fall within the acceptable recommended limits. Higher concentrations of M.P. in PEG-bases moderately increased the hardness (p<0.05). PEG-formulations showed content uniformity>90% of the average content while it was 75-83% for suppocire formulations. All formulations disintegrated in<30minutes. In-vitro release test revealed that M.P. release from 25%-MP formulations was higher than that of 50%-M.P. suppositories. Overall, results revealed the feasibility of preparing P.E.G.-or lipid-based suppositories containing M.P., which met the B.P. quality requirement


Assuntos
Polissacarídeos/agonistas , Supositórios/análise , Althaea/anatomia & histologia , Plantas Medicinais/efeitos adversos , Gestão da Qualidade Total/estatística & dados numéricos , Malvaceae/classificação
2.
Int Immunol ; 25(4): 221-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23291968

RESUMO

Dendritic cells (DCs) are antigen-presenting cells efficient in capturing pathogens, and processing their antigenic determinants for presentation to antigen-specific T cells to induce robust immune responses. Their location at peripheral tissues and the expression of pattern-recognition receptors, among them DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), facilitates the capture of pathogens before spreading. However, some pathogens have developed strategies to escape the immune system. One of the most successful is HIV-1, which targets DC-SIGN for transport to the lymph node where the virus infects CD4(+) T cells. Contact of HIV-1 with DC-SIGN is thus the first event in the pathogenic cascade and, therefore, it is the primary target point for therapies aimed at HIV infection prevention. DC-SIGN recognizes specific glycans on HIV-1 and this interaction can be blocked by competitive inhibition through glycans. Although the affinity of glycans is relatively low, multivalency may increase avidity and the strength to compete with HIV-1 virions. We have designed multivalent dendrimeric compounds based on Lewis-type antigens that bind DC-SIGN with high selectivity and avidity and that effectively block gp120 binding to DC-SIGN and, consequently, HIV transmission to CD4(+) T cells. Binding to DC-SIGN and gp120 inhibition was higher on glycodendrimers with larger molecular diameter, indicating that the geometry of the compounds is an important factor determining their functionality. Our compounds elicited DC-SIGN internalization, a property of the receptor upon triggering, but did not affect the maturation status of DCs. Thus, Le(X) glycodendrimers could be incorporated into topic prophylactic approaches for the prevention of HIV-1 transmission.


Assuntos
Moléculas de Adesão Celular/imunologia , Dendrímeros/química , Células Dendríticas/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , HIV-1/imunologia , Lectinas Tipo C/imunologia , Antígenos do Grupo Sanguíneo de Lewis/química , Polissacarídeos/farmacologia , Receptores de Superfície Celular/imunologia , Ligação Competitiva , Moléculas de Adesão Celular/agonistas , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/virologia , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Evasão da Resposta Imune , Lectinas Tipo C/agonistas , Terapia de Alvo Molecular , Polissacarídeos/agonistas , Polissacarídeos/síntese química , Receptores de Superfície Celular/agonistas , Relação Estrutura-Atividade , Internalização do Vírus/efeitos dos fármacos
3.
J Neurotrauma ; 28(7): 1295-306, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21463132

RESUMO

In adult mammals, restoration of function after peripheral nerve injury is often poor and effective therapies are not available. Previously we have shown in mice that a peptide which functionally mimics the human natural killer cell (HNK)-1 trisaccharide epitope significantly improves the outcome of femoral nerve injury. Here we evaluated the translational potential of this treatment using primates. We applied a linear HNK-1 mimetic or a functionally inactive control peptide in silicone cuffs used to reconstruct the cut femoral nerves of adult cynomolgus monkeys (Macaca fascicularis). Functional recovery was evaluated using video-based gait analysis over a 160-day observation period. The final outcome was further assessed using force measurements, H-reflex recordings, nerve histology, and ELISA to assess immunoreactivity to HNK-1 in the treated monkeys. Gait deficits were significantly reduced in HNK-1 mimetic-treated compared with control peptide-treated animals between 60 and 160 days after injury. Better outcome at 160 days after surgery in treated versus control animals was also confirmed by improved quadriceps muscle force, enhanced H-reflex amplitude, decreased H-reflex latency, and larger diameters of regenerated axons. No adverse reactions to the mimetic, in particular immune responses resulting in antibodies against the HNK-1 mimetic or immune cell infiltration into the damaged nerve, were observed. These results indicate the potential of the HNK-1 mimetic as an efficient, feasible, and safe adjunct treatment for nerve injuries requiring surgical repair in clinical settings.


Assuntos
Neuropatia Femoral/tratamento farmacológico , Mimetismo Molecular/fisiologia , Polissacarídeos/uso terapêutico , Receptores Semelhantes a Lectina de Células NK/uso terapêutico , Trissacarídeos/uso terapêutico , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Neuropatia Femoral/fisiopatologia , Macaca fascicularis , Masculino , Peptídeos Cíclicos/fisiologia , Peptídeos Cíclicos/uso terapêutico , Polissacarídeos/agonistas , Polissacarídeos/fisiologia , Receptores Semelhantes a Lectina de Células NK/agonistas , Receptores Semelhantes a Lectina de Células NK/fisiologia , Recuperação de Função Fisiológica , Trissacarídeos/agonistas , Trissacarídeos/fisiologia
4.
Blood ; 115(23): 4778-86, 2010 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20181615

RESUMO

Antibody-mediated cell depletion therapy has proven to provide significant clinical benefit in treatment of lymphomas and leukemias, driving the development of improved therapies with novel mechanisms of cell killing. A current clinical target for B-cell lymphoma is CD22, a B-cell-specific member of the sialic acid binding Ig-like lectin (siglec) family that recognizes alpha2-6-linked sialylated glycans as ligands. Here, we describe a novel approach for targeting B lymphoma cells with doxorubicin-loaded liposomal nanoparticles displaying high-affinity glycan ligands of CD22. The targeted liposomes are actively bound and endocytosed by CD22 on B cells, and significantly extend life in a xenograft model of human B-cell lymphoma. Moreover, they bind and kill malignant B cells from peripheral blood samples obtained from patients with hairy cell leukemia, marginal zone lymphoma, and chronic lymphocytic leukemia. The results demonstrate the potential for using a carbohydrate recognition-based approach for efficiently targeting B cells in vivo that can offer improved treatment options for patients with B-cell malignancies.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Linfoma de Células B/tratamento farmacológico , Polissacarídeos/agonistas , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico , Animais , Antibióticos Antineoplásicos/uso terapêutico , Células CHO , Cricetinae , Cricetulus , Doxorrubicina/uso terapêutico , Humanos , Ligantes , Lipossomos , Linfoma de Células B/imunologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Polissacarídeos/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Arch Microbiol ; 179(1): 7-14, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12471499

RESUMO

The regulation of formation of the single intracellular beta-galactosidase activity of Aspergillus nidulans was investigated. beta-Galactosidase was not formed during growth on glucose or glycerol, but was rapidly induced during growth on lactose or D-galactose. L-Arabinose, and -- with lower efficacy -- D-xylose also induced beta-galactosidase activity. Addition of glucose to cultures growing on lactose led to a rapid decrease in beta-galactosidase activity. In contrast, in cultures growing on D-galactose, addition of glucose decreased the activity of beta-galactosidase only slightly. Glucose inhibited the uptake of lactose, but not of D-galactose, and required the carbon catabolite repressor CreA for this. In addition, CreA also repressed the formation of basal levels of beta-galactosidase and partially interfered with the induction of beta-galactosidase by D-galactose, L-arabinose, and D-xylose. D-Galactose phosphorylation was not necessary for beta-galactosidase induction, since induction by D-galactose occurred in an A. nidulans mutant defective in galactose kinase, and by the non-metabolizable D-galactose analogue fucose in the wild-type strain. Interestingly, a mutant in galactose-1-phosphate uridylyl transferase produced beta-galactosidase at a low, constitutive level even on glucose and glycerol and was no longer inducible by D-galactose, whereas it was still inducible by L-arabinose. We conclude that biosynthesis of the intracellular beta-galactosidase of A. nidulans is regulated by CreA, partially repressed by galactose-1-phosphate uridylyl transferase, and induced by D-galactose and L-arabinose in independent ways.


Assuntos
Aspergillus nidulans/enzimologia , beta-Galactosidase/metabolismo , Aspergillus nidulans/citologia , Aspergillus nidulans/metabolismo , Galactose/agonistas , Galactose/metabolismo , Glucose/antagonistas & inibidores , Glucose/metabolismo , Glicerol/metabolismo , Kluyveromyces/metabolismo , Lactose/metabolismo , Mutação , Polissacarídeos/agonistas , Polissacarídeos/classificação , Polissacarídeos/metabolismo , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
6.
Microbiol Immunol ; 46(7): 503-12, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12222939

RESUMO

The cytokine-inducing activities of fungal polysaccharides were examined in human monocytes in culture, with special reference to CD14 and Toll-like receptors (TLRs). Tumor necrosis factor alpha (TNF-alpha) production by monocytes was markedly induced in a dose-dependent manner upon stimulation with cell walls from Candida albicans and mannan from Saccharomyces cerevisiae and C. albicans, although relatively high concentrations (10 to 100 microg/ml) of stimulants were required for activation as compared with the reference lipopolysaccharide (LPS) (1 to 10 ng/ml). The yeast form C. albicans and its mannan and cell wall fractions exhibited higher TNF-alpha production than respective preparations from the hyphal form. Only slight TNF-alpha production was induced by the S. cerevisiae glucan. The TNF-alpha production triggered by reference LPS and purified fungal mannans required the presence of LPS-binding protein (LBP), and these responses were inhibited by anti-CD14 and anti-TLR4 antibodies, but not by anti-TLR2 antibody. In contrast to the activity of LPS, the activity of purified S. cerevisiae mannan was not inhibited by polymyxin B. These findings suggested that the mannan-LBP complex is recognized by CD14 on monocytes and that signaling through TLR4 leads to the production of proinflammatory cytokines in a manner similar to that induced by LPS.


Assuntos
Proteínas de Fase Aguda , Proteínas de Drosophila , Receptores de Lipopolissacarídeos/fisiologia , Mananas/farmacologia , Glicoproteínas de Membrana/fisiologia , Monócitos/imunologia , Receptores de Superfície Celular/fisiologia , Fator de Necrose Tumoral alfa/biossíntese , Leveduras , beta-Glucanas , Candida albicans/metabolismo , Proteínas de Transporte/metabolismo , Endotoxinas/análise , Glucanos/análise , Humanos , Receptores de Lipopolissacarídeos/química , Glicoproteínas de Membrana/química , Monócitos/citologia , Monócitos/efeitos dos fármacos , Polimixina B/metabolismo , Polissacarídeos/agonistas , Polissacarídeos/metabolismo , Receptores de Superfície Celular/química , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Receptores Toll-Like , Leveduras/metabolismo , Zimosan/análise
7.
Nihon Yakurigaku Zasshi ; 104(5): 363-8, 1994 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-7829022

RESUMO

The sites of action of many chemical agents that modify the contraction of smooth muscle are in the smooth muscle membrane. However, a few agents, such as calmodulin inhibitors and protein kinase inhibitors, interact directly with contractile elements of the actomyosin system so as to modify smooth muscle contraction. Here, we describe experimental procedures that are applicable for the screening of smooth muscle relaxants with this mode of action. Myosin B was extracted from chicken gizzard smooth muscle. Because myosin B was a crude preparation of smooth muscle actomyosin, it consisted of regulatory proteins of calmodulin, myosin light chain kinase and protein phosphatase in addition to the contractile proteins of actin and myosin. Interaction of chemical agents with these proteins could be detected by measuring the Mg-ATPase activity of the myosin B preparation. Then we examined whether the agents that altered the ATPase activity was associated with changes in phosphorylation of myosin light chain. If the levels are altered, the agents may interact with the regulatory protein(s). If not, the site of their action was in the contractile proteins. The analysis with these respective proteins will be also described.


Assuntos
Indóis , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Miosinas/fisiologia , Polissacarídeos/agonistas , Amilorida/agonistas , Animais , Carbazóis/agonistas , Galinhas , Técnicas In Vitro , Músculo Liso/enzimologia , Miosinas/metabolismo , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...