Antimicrobial and antioxidant activities of the various extracts of Verbascum pinetorum Boiss. O. Kuntze (Scrophulariaceae)

BACKGROUND AND OBJECTIVES

The present study was performed to evaluate the in vitro antimicrobial and antioxidant properties of various extracts of Verbascum (V.) pinetorum, a member of Scrophulariaceae family. While the antimicrobial activity of various extracts of V. pinetorum was determined with agar-well diffusion method, the antioxidant activity was examined with two complementary test systems, namely 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and beta-carotene/linoleic acid test systems.

RESULTS

The hexane extract exhibits antimicrobial activity against few microorganisms. However, dichloromethane, direct methanol and methanol/chloroform extracts are effective on a broad range of microorganisms. Among the tested bacteria Haemophilus influenzae was found to be the most sensitive bacterium. The 50% (IC50) inhibition activity of the methanolic extract of V. pinetorum on the free radical DPPH was determined as 13.04 mg/ml. In the case of the linoleic acid system, oxidation of linoleic acid was inhibited by methanolic extract of V. pinetorum, which showed 89.39% inhibition that is quite close to the value of the synthetic antioxidant reagent butylhydroxytoluene (BHT), 92.46%. Iridoid glycosides, flavonoids and saponins were determined as the major natural compounds in the methanolic extracts. The total phenolic components of V. pinetorum were found as 42.45 mg/g gallic acid equivalent.

CONCLUSION

The results provide evidence that the extracts of V. pinetorum contained iridoid glycosides, flavonoids, saponins and phenolic compounds which may be responsible for the substantial antimicrobial and antioxidant activities.

Acute arsenic self-poisoning for suicidal purpose in a dentist: a case report

Arsenic is a classical poison that has been historically used since ancient times for homicidal purposes. More recently, episodes of deliberate or unintentional arsenic self-poisoning have been increasingly reported. We describe here a case of a 77-year old male patient with a history of major depression, who attempted suicide by ingestion of 4 g of arsenic trioxide. The man, a dentist by profession, used arsenic preparations for pulp devitalization. The patient was admitted to our hospital 5 h after arsenic ingestion with nausea and vomiting. Plain radiograph of the abdomen showed radio-opaque material in the stomach and small intestine. Nasogastric lavage, activated charcoal, and chelators were used to remove arsenic. On day 3, endoscopy disclosed the presence of gastritis and superficial ulcers. The patient developed significant anemia (Hb: 8.7 g/dL on day 7) without significant signs of hemolysis. He gradually recovered from anemia within 5 months. The patient did not suffer any adverse outcome in spite of having ingesting 4 g of arsenic, approximately 20 times the lethal dose.

Mechanisms of Staphylococcus aureus induced apoptosis of human endothelial cells

Staphylococcus aureus plays an important role in sepsis, pneumonia and wound infections. Here, we demonstrate that infection with several S. aureus strains results in apoptosis of human endothelial cells. S. aureus induced an activation of cellular caspases, the acid sphingomyelinase, a release of cytochrome c and a stimulation of Jun NH2-terminal kinase (JNK). The significance of these findings is indicated by a prevention of S. aureus triggered apoptosis of human cells deficient for ASM or upon genetic or pharmacological inhibition of JNK or caspases, respectively.

Invasion of human epithelial cells by Pseudomonas aeruginosa involves src-like tyrosine kinases p60Src and p59Fyn

Pseudomonas aeruginosa plays a major role in respiratory tract infections or sepsis in patients with cystic fibrosis or upon suppression of the immune system. Several P. aeruginosa strains have been shown to be internalized by human epithelial cells; however, the molecular mechanisms of the invasion process are poorly characterized. Here, we show that the internalization of P. aeruginosa into human epithelial cells results in and requires activation of the Src-like tyrosine kinases p59Fyn and p60Src and the consequent tyrosine phosphorylation of several eukaryotic proteins. The significance of Src-like tyrosine kinase activation is shown by an almost complete blockade of P. aeruginosa internalization, but not adhesion, upon inhibition of Src-like tyrosine kinases. Likewise, inhibition of P. aeruginosa binding to CFTR, which has been shown to block P. aeruginosa internalization, prevents Src and Fyn activation, supporting a pivotal role of Src-like tyrosine kinases for invasion by P. aeruginosa.

Blue rubber bleb nevus syndrome

A 26-yr-old man was admitted with malaise and melena. During the physical examination, six hemangiomas were spotted on the skin, and laboratory evaluations proved the existence of severe iron deficiency anemia (Hb 2.9 g/dl). Upper endoscopy and small bowel follow-through revealed no pathology. Colonoscopy documented the presence of a blue-red cavernous hemangioma, 1 cm in diameter, at the splenic flexura. The skin and colonic lesions were typical; thus, blue-rubber-bleb-nevus syndrome was diagnosed. The patient was given blood transfusions followed by oral iron supplementation. He refused further evaluation or surgery and is still fine after a follow-up period of 6 months. Here, we present a discussion of this case, together with a detailed review of the literature.