<Emphasis Type="Italic">Petiveria alliacea</Emphasis> extracts uses multiple mechanisms to inhibit growth of human and mouse tumoral cells

Background  

There is ethnopharmacological evidence that Petiveria alliacea can have antitumor activity; however, the mechanism of its cytotoxic activity is not well understood. We assessed multiple in vitro biological activities of an ethyl acetate soluble plant fraction over several tumor cell lines.     

Inhibition of spermatozoa maturation in rhesus monkey by cyproterone acetate

The morphology of spermatozoa from the initial segment, caput, corpus and cauda epididymides of normal and cyproterone acetate-treated animals was studied using light and scanning electron microscopy to understand the changes taking place during spermatozoa maturation. A progressive and significant decrease in the percentage of spermatozoa that retained the cytoplasmic droplet and a shift in its position from proximal end of the midpiece to its distal end were seen during epididymal transit; these events were inhibited in cyproterone acetate-treated animals. A large percentage of spermatozoa from the initial segment and the caput epididymides showed coiling of the spermatozoa tail which involved the midpiece, principal piece and the endpiece. The percentage of spermatozoa that showed the coiled tail decreased; a gradual straightening of the spermatozoa tail with less complex types of coiling was also seen during epididymal transit. Cyproterone acetate reversed these changes occurring during maturation. These results indicate that spermatozoa maturation in the rhesus monkey, occurring between the corpus and cauda epididymides, is an androgen-dependent event.     

Modulation of acid secretion in common bile duct ligation-related gastropathy in Wistar rats

BACKGROUND: Portal hypertensive gastropathy is associated with fundic gland atrophy, resulting in a decrease in chief and parietal cells, and diminished acid secretion. METHODS: Acid secretion by isolated parietal cells was measured (acridine orange retention), along with the levels of various second messengers (intracellular Ca(2+), cyclic adenosine monophosphate and protein kinase C) in the common bile duct, ligated portal hypertensive rats and compared with sham-operated controls. RESULTS: There was a significant decrease in the response of isolated parietal cells to the secretagogues histamine and carbachol. This resulted in the blunted acid secretion in the common bile duct ligated group. In addition, all the second messengers studied were significantly decreased as compared with the sham-operated controls. CONCLUSION: These results suggest that the blunted acid secretory response in the portal hypertensive rat is caused by an alteration in the intracellular signal transduction mechanism.     

Histochemical demonstration of nitric oxide synthase-like immunoreactivity in epiplexus cells and choroid epithelia in the lateral ventricles of postnatal rat brain induced by an intracerebral injection of lipopolysaccharide

The present in vivo study showed the expression of nitric oxide synthase-like immunoreactivity in epiplexus cells in the lateral ventricles induced by intracerebral injection of lipopolysaccharide into postnatal rats. Nitric oxide synthase-like immunoreactivity was vigorously expressed in epiplexus cells 1 and 3 days after the lipopolysaccharide injection, but by 7 days post-injection, it became undetectable. The expression of nitric oxide synthase-like immunoreactivity was also observed in some of the choroid epithelial cells. The nitric oxide synthase-like immunoreactivity in these cells appeared to be more intense in the ventricle ipsilateral to the LPS injection than that on the contralateral side. The immunostaining patterns of OX-42 and OX-6 for the detection of complement type 3 receptors and major histocompatibility complex class II antigens respectively paralleled that of anti-nitric oxide synthase, indicating that lipopolysaccharide-induced nitric oxide synthase-like immunoreactivity was primarily in epiplexus cells. Immunoelectron microscopy revealed that the nitric oxide synthase-like immunoprecipitate in epiplexus cells and choroid epithelial cells filled the entire cytoplasm and in some areas associated with the membranes of some of the organelles especially the mitochondria, suggesting that the enzyme is mainly cytosolic. It is speculated that nitric oxide synthase in these cells is involved in the synthesis of nitric oxide. The nitric oxide production, if any, through the enzymatic activity of nitric oxide synthase in epiplexus cells as well as the choroid epithelial cells may be involved in host defense against bacterial endotoxin in the ventricular system of postnatal rat brain.     

Phagocytic and bactericidal activities of macrophages from Mycobacterium leprae-infected normal and immunosuppressed mice

Phagocytic and bactericidal activities were studied in Mycobacterium leprae-infected normal (NI) and thymectomized/irradiated (TRI) mice at different time periods. No significant differences were seen in the phagocytic activity for Staphylococcus aureus at 3, 6, and 9 months in the normal infected (NI) and normal control (NC) mice. A slight but significant decrease in the phagocytosis of S. aureus was seen in the TRI as compared to the NI group at 3 months which recovered at 6 months. Phagocytosis of sheep erythrocytes was depressed in the TRI as compared to the NI group at 6 months only. No significant differences in the phagocytosis of latex particles were seen in any of the groups at any time of infection. Bactericidal activity was significantly reduced in the NI group as compared to the NC group and, similarly, in the TRI group as compared to the TRC group at all periods of infection. The M. leprae-infected T/R 900 group (TRI) showed more decrease in bactericidal activity when compared to the normal infected (NI) group.     

Argon laser trabeculoplasty in Asian eyes

Summary Twenty two Asian eyes suffering from open angle glaucoma were treated by argon laser trabeculoplasty and were followed for an average of eleven months. 77.27% of eyes were controlled with ALT alone. The pressure lowering effect of argon laser trabeculoplasty in this series was found to be consistent. Argon laser trabeculoplasty may become the preffered method of treating open angle glaucoma in the Asian population.     

Effect of incorporation of isabgol husk in a low fibre diet on faecal excretion and serum levels of lipids in adolescent girls

The effect of consumption of isabgol husk for 3 weeks on faecal excretion and serum levels of lipids was investigated in 11 adolescent girls. The consumption of isabgol husk lowered serum lipids and increased faecal fat.