Effect of Solanum nudum steroids on uninfected and Plasmodium falciparum-infected erythrocytes

Steroids from Solanum nudum (SNs) have demonstrated antiplasmodial activity against erythrocytic stages of the Plasmodium falciparum strain FCB-2. It is well known that steroids can alter the membrane function of erythrocytes. Thus, we assessed alterations in the membranes of uninfected red blood cells, the parasite invasiveness and the solute-induced lysis of parasitised red blood cells (pRBCs). induced by SNs. We found that most merozoites were unable to invade SN-treated erythrocytes. However, transmission electron microscopy revealed no effect on the morphology of uninfected erythrocytes treated with either SN2 or diosgenone and neither SN induced haemolysis of uninfected erythrocytes. SN2 and SN4 inhibited isosmotic sorbitol and alanine-induced haemolysis of pRBCs. In contrast, diosgenone and SN1 did not inhibit solute-induced haemolysis. The inhibition of solute-induced lysis of parasitised erythrocytes by SN2 and SN4 suggest an action of these SNs on new permeability pathways of pRBCs.

Esteróides e cumarina em calos de Mikania glomerata Sprengel / Steroides and coumarin from callus of Mikania Glomerata Sprengel

O estudo fitoquímico do extrato diclorometânico dos calos obtidos a partir de segmentos foliares de Mikania glomerata Sprengel resultou no isolamento dos esteróides campesterol, estigmasterol e ß-sitosterol e da cumarina, não tendo sido detectado nenhum diterpeno do tipo caurano

Isolation and characterisation of bioactive steroid from a prawn.

Dried prawns (Nematopalaemon tenuipes) were extracted with various solvents like petroleum ether, chloroform and methanol. Petroleum ether extract (PEP), tested for antimicrobial, larvicidal and haemolytic activity on human blood cells showed a positive haemolytic activity and effectively inhibited growth of mosquito larvae. Chemical investigation of this extract confirmed the presence of haemolytic steroid norcholestane.

Tissue culture studies on Australian solanum [S. aviculare]

Callus cultures of Solanum aviculare forst. were established from cotyledons, leaves, stem and root segments. Callus was propagated successfully on Abou-Mandour's medium. It remained undifferentiated except for root differentiation, observed in stem and root calli

Desenvolvimento de anticorpos monoclonais contra progesterona e seu emprego em dosagens séricas / Development of monoclonal antibodies against progesterona and its utility in serum assays

Anticorpos monoclonais foram desenvolvidos contra um derivado de progesterona-11-hemissucinato acoplado a albumina bovina. O estudo comparativo da especificidade do anticorpo de melhores características (F4P4) contra um anticorpo policlonal, produzido em coelho contra o mesmo tipo de derivado, mostrou características equivalentes. O radioimunoensaio desenvolvido com o monoclonal emprega extraçåo prévia do soro, traçador iodado e método de separaçåo com polietilenoglicol. A sensibilidade com o emprego de amostras de 0,5ml de soro é de 2 ng/dL (0,06 nmol/L) e o coeficiente de variaçåo intraensaio mostrou-se inferior a 10 entre as concentraçöes de 17 e 845 ng/dL (0,54 e 26,9 nmol/L). A dosagem, em paralelo, de 37 amostras de soro com método aqui descrito e um radioimunoensaio clássico mostrou alta correlaçåo (r=0,912). A comparaçåo foi feita também com um ensaio comercial (DELFIA Progesterone Kit), que dispensa extraçåo, em 154 amostras de soro, obtendo-se uma correlaçåo de r=0,900, sendo que o ensaio empregando o anticorpo monoclonal apresenta valores mais exatos na faixa inferior a 100 ng/dL (3,18 nmol/L)

Chemical and pharmacological investigation of Solanum species of Brazil: a search for solasodine and other potentially useful therapeutic agents

A systematic search for solasodine, an important staring material for the partial synthesis of steroidal hormones as well as other potentially bioactive constituents of various Solanum species of Brazil has been undertaken. Thus, the fruits of S. paludosum, S. asperum, S. sessiliforum and Solanum sp. were found to contain significant amounts of solasodine. The root bark of S. paludosum which showe durare like activity yelded tomatidenol and another yet unidentified alkaloid responsible for the biological activity. The fruits of S. asperum yelded a new spirosolane alkaloid, solaparnaine. The stem bark of S. pseudo-quina showed convulsive and exitatory activity from which (25S)-isosolafloridine was identified as the active principle. In addition, the latter alkaloid was also found to show antimicrobial activity.

Bioactive glycosides from Chinese medicines

Glycosides are the bioactive components of many famous Chinese medicines. Here reported are some bioactive glycosides we discovered from Chinese medicines in recent years. (1) Pheolic glycosides from Chinese medicines: Gastrodia elata, acontium austroynanense and Helicia erratica, three bioactive phenolic glycosides were discovered and two of them have been developed into new drugs. (2) Terpenoidal glycosides: a) Monoterpenoid: the sweroside from Swertia mollensis has been developed intro an anti-hepatitis drug; b) Diterpenoid: Phlomis betonicoides contains sweet glycoides; c) Triterpenoid: many biologically active triterpenoid glycosides were isolated from Panax plants and Siraitia grosvenorii. (3) Steroidal glycosides: a) C21-steroid: Cynanchum otophyllum and C. atratrum contain anti-epilepsy and-tumor glycosides; b) C27-steroid Hemostatic saponins were found in Paris polyphylla.