Characterization of cytotoxic T-lymphocyte epitopes and immune responses to SARS coronavirus spike DNA vaccine expressing the RGD-integrin-binding motif.

Integrins are critical for initiating T-cell activation events. The integrin-binding motif Arg-Gly-Asp (RGD) was incorporated into the pcDNA 3.1 mammalian expression vector expressing the codon-optimized extracellular domain of SARS coronavirus (SARS-CoV) spike protein, and tested by immunizing C57BL/6 mice. Significant cell-mediated immune responses were characterized by cytotoxic T-lymphocyte (51)Cr release assay and interferon-gamma secretion ELISPOT assay against RMA-S target cells presenting predicted MHC class I H2-Kb epitopes, including those spanning residues 884-891 and 1116-1123 within the S2 subunit of SARS-CoV spike protein. DNA vaccines incorporating the Spike-RGD/His motif or the Spike-His construct generated robust cell-mediated immune responses. Moreover, the Spike-His DNA vaccine construct generated a significant antibody response. Immunization with these DNA vaccine constructs elicited significant cellular and humoral immune responses. Additional T-cell epitopes within the SARS-CoV spike protein that may contribute to cell-mediated immunity in vivo were also identified.

Analgesic and antiinflammatory activities of vernonioside B2 from Vernonia condensata.

Vernonioside B2 isolated from the methanol extract of the Brazilian herb Vernonia condensata Baker was evaluated in vivo for analgesic and antiinflammatory activities. The compound reduced writhings (93.28%) and Evans blue dye diffusion (91.80%) induced by acetic acid (0.1 N) in a dose-dependent manner.

Effect of leaf essential oil from Piper solmsianum C.DC. in mice behaviour.

The essential oil from Piper solmsianum leaves and its major compound (sarisan) were tested to verify their influences upon mice behaviour. The essential oil was obtained by hydrodistillation in a modified Clevenger extractor and analysed by GC/ MS. This analysis revealed in the oil the presence of monoterpenes, sesquiterpenes and of arylpropanoids. The compound sarisan, a myristicin analogue, was isolated from the oil to perform the pharmacological tests. Emulsions of the oil and of sarisan (5.0 and 10.0% v/v) were used in the tests. Pentobarbital (30 mg/ kg s.c.) or diazepam (2.5 mg/ kg s.c.) were tested as standard drugs to verify depressant or anxiolytic effects, respectively. Both essential oil and sarisan showed to have exciting and depressant effects in the tested animals.

Plant natural products active against snake bite--the molecular approach.

The article surveys the substances identified in plants reputed to neutralize the effects of snake venoms. Protective activity of many of them against the lethal action of the venom of the jararaca (Bothrops jararaca) snake was confirmed by biological assays. It was shown that all belong to chemical classes capable of interacting with macromolecular targets--receptors and enzymes. In a few cases it has been shown that exogenous natural micromolecules can mimic the biological activity of endogenous macromolecules. From the evidence presented, it can be inferred that micromolecules which neutralize the action of snake venoms mechanistically replace endogenous antitoxic serum proteins with venom neutralizing capacity such as produced by some animals.

Anti-inflammatory and immunologically active polysaccharides of Periandra mediterranea.

Three polysaccharides, glucans with mean M(r)'s of 1.5 x 10(5), 3.6 x 10(4) and 2.1 x 10(4), were isolated from dried roots of Periandra mediterranea by fractionation on Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that they have a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with both (3-->4) and (4-->6) branching points. The polysaccharides enhance phagocytosis in vivo, and exhibit anti-inflammatory activity.

Molluscicidal constituents of Marsypianthes chamaedrys.

Marsypianthes chamaedrys is a common herb that occurs in the North and Northeast regions of Brazil. Phytochemical studies showed this plant to be rich in triterpenoids. The hexane extract of M. chamaedrys yielded, after chromatographic separations, two mixtures: the first containing monohydroxylated-compounds (alpha-amyrin, beta-amyrin, lupeol and germanicol) and the second, dihydroxylated compounds (chamaedrydiol, castanopsol, 2alpha-hydroxylupeol and epigermanidiol). Molluscicidal tests were performed for the crude hexane extract and for mixtures I and II. Mixture II showed high activity.

Triaga Brasilica: renewed interest in a seventeenth-century panacea.

Theriacs (electuaries prepared by mixing extracts of many plants) were known from antiquity until the eighteenth century as remedies for all kinds of envenomation, above all those due to the bites and stings of venomous animals, especially snakes. In colonial Brazil, the 'Brazilian theriac' was developed by Jesuit priests by gradually substituting native plants for components of their European model. Most of these ingredients, mentioned in an old manuscript, can be identified by their common names, which have survived the centuries.

Pharmacological Screening of Plants Recommended by Folk Medicine as Snake Venom Antidotes; IV. Protection against Jararaca Venom by Isolated Constituents1.

Fifteen Compounds, isolated from plants reputed as snake venom antidotes, belonging to different classes of natural products, were shown to protect mice to a significant degree against the lethal action of the venom of BOTHROPS JARARACA snakes. Administration was by the oral route, one hour prior to envenomation. The substances are nitrogen-free, low-molecular-weight compounds for which some kind of biodynamic activity has previously been reported. The fact that they are mostly trivial, naturally-occurring compounds should explain why plants used as snake-bite antidotes are so widely distributed over the plant kingdom.

Pharmacological screening of plants recommended by folk medicine as snake venom antidotes; IV. Protection against jararaca venom by isolated constituents.

Fifteen compounds, isolated from plants reputed as snake venom antidotes, belonging to different classes of natural products, were shown to protect mice to a significant degree against the lethal action of the venom of Bothrops jararaca snakes. Administration was by the oral route, one hour prior to envenomation. The substances are nitrogen-free, low-molecular-weight compounds for which some kind of biodynamic activity has previously been reported. The fact that they are mostly trivial, naturally-occurring compounds should explain why plants used as snake-bite antidotes are so widely distributed over the plant kingdom.

Pharmacological screening of plants recommended by folk medicine as anti-snake venom--I. Analgesic and anti-inflammatory activities.

We have observed that several plants used popularly as anti-snake venom show anti-inflammatory activity. From the list prepared by Rizzini, Mors and Pereira some species have been selected and tested for analgesic activity (number of contortions) and anti-inflammatory activity (Evans blue dye diffusion--1% solution) according to Whittle's technique (intraperitoneal administration of 0.1 N-acetic acid 0.1 ml/10 g) in mice. Previous oral administration of a 10% infusion (dry plant) or 20% (fresh plant) corresponding to 1 or 2 g/kg of Apuleia leiocarpa, Casearia sylvestris, Brunfelsia uniflora, Chiococca brachiata, Cynara scolymus, Dorstenia brasiliensis, Elephantopus scaber, Marsypianthes chamaedrys, Mikania glomerata and Trianosperma tayuya demonstrated analgesic and/or anti-inflammatory activities of varied intensity.

Anti-inflammatory properties of new bioisosteres of indomethacin synthesized from safrole which are sulindac analogues.

The anti-inflammatory activities of new compounds (I, II, III and IV) synthesized in 30% overall yield from the abundant natural product safrole, the principal chemical constituent of the oil of sassafras (Ocotea pretiosa, Lauraceae), were determined in mice. The synthesis of these new indenyl-acetic acids (I and II) and indenyl-propionic acids (III and IV) was based on the minimal structural features of non-steroid anti-inflammatory agents of the aryl- or heteroarylcarboxylic acid group. The compounds exhibited potencies 4- to 10-fold less than that of indomethacin in inhibiting carrageenan-induced hindpaw edema. In contrast, like sulindac, all the new compounds were more potent than indomethacin in antagonizing writhing pain and increased vascular permeability caused by acetic acid. The results confirm the anticipated bioisosteric relationship between these synthetic derivatives, designed as sulindac analogues, and the classical non-steroidal anti-inflammatory agent, indomethacin.

Anti-inflammatory preoperties of new bioisosteres of indomethacim synthesized from safrole which are sulindac analogues

The anti-inflammatory activities of new compounds (I, II, II and IV) synthesized in 30% overall yield from the abundant natural product safrole, the principal chemical constituent of the oil of sassafras (Ocotea pretiosa, Lauraceae), were determined in mice. The synthesis of these new indenyl-acetic acids (I and II) and indenyl-propionic acids (III and IV) was based on the minimal structural features of non-steroid anti-inflammatory agents of the aryl- or heteroarylcarboxylic acid group. The compounds exhibited potencies 4- to 10-fold less than that of indometacin in inhibiting carrageenan-induced hindpaw edema. In contrast, like sulindac, all the new compounds were more potent than indomethacin in antagonizing writhing pain and increased vascular permeability caused by acetic acid. The results confirm the anticipated bioisosteric relationship between these synthetic derivatives, designed as sulindac analogues, and the classical non-steroidal anti-inflammatory agent, indomethacin