Biosynthesis,secretion and in vivo isotopic labelling of venom of the Egyptian cobra, Naja haje annulifera

The venom glands of Elapidae differ from those of the Viperidae by lacking an expanded central lumen; the venom is stored in the tubular lumina as well as inside the cells in densely packed secretion granules. Using isotope tracer techniques, it was found that in the Egyptian cobra (Naja haje annulifera) venom is secreted both from pre-existing and from newly-formed granules. The rate of protein biosynthesis peaks at 4–9 days after venom was extracted (milked) from the glands. Highly labelled toxins (1–10 mCi/mmole protein) were isolated in good yield from the venom of snakes chronically intubated and infused i.p. with (³H)-amino acids. Repeated Fluothane (Halothane) anaesthesias and venom collections had no ill effect on venom yield. The radioactive venom and its component toxins retained full biological potency.     

Carcinogenic and neurotoxic components in the cycad Encephalartos altensteinii Lehm. (Family Zamiaceae)

Aqueous extracts from seeds ofEncephalartos altensteinii were passed through an Amicon UM-2 ultrafiltration membrane with a general molecular mass retentivity of 1000. The retentate produced neurotoxic symptoms when administered to guinea pigs. Macrozamin (methylazoxymethanol-β-primeveroside), a potent carcinogen, was isolated from the diffusate, and after purification by means of adsorption on charcoal and ion-exchange chromatography, was obtained in crystalline form     

Fatal systemic arterial air embolism following lung needle aspiration

Fatal systemic arterial air embolism occurred as a complication of percutaneous fine-needle aspiration of the lung, immediately following cytologic sampling of a vasculitic lesion of Wegener granulomatosis. This complication is extremely rare, and it may have been caused by the biopsy of abnormal veins, in which transmural inflammation prevented the normal vasoconstrictive responses to injury.     

Method of questioning and the accuracy of eyewitness testimony

System variables are integrally part of factors that can be controlled by the legal system to enhance the accuracy of testimony by eyewitnesses. Apart from examining the relationship between questioning as system variable and the accuracy of testimony, the present study furthermore explores the relationship between type of questioning and certain biographical variables (occupation, age, gender and race). To achieve the aim of the study, 412 respondents consisting of 11 to 14-year-olds, university students, the public and Police College students participated and were exposed to open-ended or closed-ended questions. It was found that the participants who responded to the closed-ended questions were significantly more accurate than those who answered the open-ended questions. All the biographical groups, except the public, were more accurate in responding to the closed-ended questions. The scholars obtained the lowest scores (although not always significant) for both the open-ended and closed-ended questions. With respect to age the 18 to 25-year-olds obtained significantly higher scores than the other groups for the closed-ended questions. Whites performed significantly better than blacks in response to the open-ended and closed-ended questions.     

Rosa roxburghii supplementation in a controlled feeding study increases plasma antioxidant capacity and glutathione redox state

Summary Background Rosa roxburghii (RR) is a plant of which the fruit juice has been used as a medicinal remedy for a variety of diseases. It has been proposed that the putative beneficial properties are related to its antioxidant potential. Aim of study We investigated the contribution of a supplemented RR fruit sample on the antioxidant status in a cohort of healthy humans. Methods A total of 36 young, healthy and non–smoking individuals were recruited for this randomised placebo–controlled, single–blind trial. The study was diet controlled over a five–week period with a two week run–in period before participants daily received a placebo or an encapsulated supplement of RR sample. Total antioxidant capacity, glutathione redox state, glutathione reductase, glutathione peroxidase, superoxide dismutase and 8–OHdG levels were measured. Results RR supplementation significantly increased plasma antioxidant capacity (p = 0.04) and GSH:GSSG ratios in blood (p = 0.03). No significant changes in 8–OHdG levels, total glutathione levels or antioxidant modulating enzymes were detected suggesting that the observed shift of the glutathione redox state probably occurs via the antioxidant mediated protection of GSH. Conclusions We conclude that these findings support the putative beneficial properties that have been linked to Rosa roxburghii as a dietary supplement that can enhance antioxidant status.     

Asymptomatic total hip prosthesis: natural history determined using Tc- 99m MDP bone scans

A prospective study was performed with 97 patients who had undergone total hip replacement surgery and who were not experiencing pain or other symptoms or problems. The study was intended to determine the normal postoperative appearance of radionuclide scans of the hip following administration of technetium-99m methylene diphosphonate. Five areas of the prostheses were evaluated. Results showed that 6 months after implantation activity around the lesser trochanter and prosthesis shaft became insignificant. Activity around the acetabulum, greater trochanter, and prosthesis tip stabilized approximately 2 years after surgery; approximately 10% of patients in the study had persistent activity in these areas. Familiarity with this normal progression is fundamental to interpretation of postoperative bone scans in patients with total hip prosthesis.