Evaluation of a method to determine the natural occurrence of aflatoxins in commercial traditional herbal medicines from Malaysia and Indonesia

Traditional herbal medicines, popularly known as ‘jamu’ and ‘makjun’ in Malaysia and Indonesia, are consumed regularly to promote health. In consideration of their frequent and prolonged consumption, the natural occurrence of aflatoxins (AF) in these products was determined using immunoaffinity column clean-up and high-performance liquid chromatography with pre-column derivatization. The evaluated method, which entails dilution of sample extracts with Tween 20–phosphate buffered saline (1:9, v/v) and a chromatographic system using isocratic mobile phase composed of water–methanol–acetonitrile (70:20:10, v/v/v), was effective in separating AFB₁, AFG₁ and AFG₂ from interference at their retention times. Results were confirmed using post-column derivatization with photochemical reactor. For 23 commercial samples analyzed, mean levels (incidence) of AFB₁, AFB₂ and AFG₁ in positive samples were 0.26 (70%), 0.07 (61%) and 0.10 (30%) μg/kg, respectively; one sample was positive for AFG₂ at a level of 0.03 (4%) μg/kg. In contrast to the high levels of AF in crude herbal drugs and medicinal plants reported previously by other researchers, the low contamination levels reported in this study may be attributed to the higher selectivity to AF of the method applied. Based on the AFB₁ levels and the daily consumption of positive samples, a mean probable daily intake of 0.022 ng/kg body weight was calculated.     

Severe Sexual Harassment on Social Networking Sites: Belgian Adolescents’ Views

Online sexual harassment is increasingly encountered by adolescents and is associated with various negative psychosocial outcomes. In particular, social networking sites (SNSs) may facilitate sexual harassment. This study used focus groups to examine sexual harassment on SNSs from adolescents’ (aged 12–18 years) point of view: what do they perceive as severe cases and who do they think should play a role in addressing them. The qualitative data suggested that sexual harassment was appraised as more severe when it concerned personally targeted gender harassment, situations with restricted escape possibilities, the use of insulting words, the non-consensual use of pictures for sex-related purposes, or frequent adult-initiated sexual attention. Adolescents think that educating potential victims and harassers is important. In addition, SNS providers can play a crucial role in decreasing the impact of sexual harassment by providing a safe environment and by warning or sanctioning harassers.     

Internet Information on Heart Disease in Men

Summary

Finding information on heart disease in men might seem as easy as logging on to a favorite search engine, finding the right category, and perusing the available links. However, in trying several prominent search engines, this turned out not to be the case. One important reason for the lack of information is that heart disease has declined 60% since 1950. Nevertheless, heart disease is still the leading killer among men. An advanced search on a search engine (heart disease as a phrase and man or men) still yields an unwieldy number of pages, about 90,000. In an effort to bridge this gap, the author examines a number of governmental, organizational, and consumer Web sites containing high-quality information on heart disease.     

Changes in the Biochemical Profiles of Mid-Cervically Located Adenosine A1 Receptors After Repeated Theophylline Administration in Adult Rats

Abstract

Background/Objective: Adenosine A1 receptors localized in the phrenic motoneurons (PMNs), where the axons of the descending bulbospinal respiratory make synaptic contacts, may be involved in theophylline- induced respiratory-related activity in rats. The objective of this study was to characterize the biochemical profiles of adenosine A., receptors in 2 groups of rats: (a) naive and (b) theophylline-treated (3-day oral administration).

Methods: Biochemical binding characteristics of adenosine A1 receptors in the C3 to C5 (PMN) of adult rats were assessed in naive (n = 6) and theophylline-treated animals (n = 6) using [3H]-DPCPX (10 pmol/L to 30 nmol/L), the specific adenosine A1 receptor antagonist in saturation-binding assays. Competition assays used theophylline as the competing ligand (20 mmol/L to 20 pmol/L), and protein concentration was determined with the Bradford assay using a range of standards (0.016-1.0 mg/mL).

Results: In saturation-binding assays in naive animals, the A1 receptor was characterized by a single binding site with Smax and Kd values of 256.00 ± 32.13 fmoi/mg protein and 2.89 ± 0.45 nmol/L, respectively. Analysis of the isotherm in theophylline-treated animals showed 1 site with Smax and Kd values of 219.00 ± 26.3 fmol/mg protein and 0.60 ± 0.21 nmol/L, respectively, and a second site characterized by Smax and Kd values of 492.6 ± 3.15 fmol/mg protein and 14.09 ± 2.06 n mol/L, respectively.

Conclusions: Theophylline administration revealed 2 binding sites on receptors (characterized by the specific adenosine A1 antagonist, [3H]-DPCPX) located in the vicinity of phrenic motoneurons (C3-C5). Alteration of the receptor profiles after theophylline may underlie the respiratory-related actions of the drug.     

The Effects of Water and a Protective Agent on Gamma-ray Induced Free Radicals in Mustard Seeds

Summary

Electron-spin-resonance experiments on irradiated seeds have shown that the radicals induced by gamma-radiation are very sensitive to the moisture-content of the seeds. However, at x-band frequencies the dielectric effect of the water in the sample has limited such experiments to moisture-contents of about 12 per cent. By using an E.S.R. spectrometer of low microwave frequency the gamma-induced radicals in white-mustard seeds have been studied with moisture-contents of up to 70 per cent by weight, and measurements made while gamma-irradiation was in progress. Both radical production and radical decay are studied in seed samples of various moisture-contents and in seeds treated with the protective agent AET.     

Cancer Risk Associated with Residential Proximity to Industrial Sites: A Review

In this study, the authors sought to review available epidemiologic studies of cancer risk and its association with residence in a neighborhood characterized by industrial sites and to discuss options for future study design. The authors attempted to identify all case-control studies published from January 1980 through July 1997 in which investigators examined exposure resulting from residential proximity to an industrial site neighborhood relative to an increased risk of lung, urinary tract, and lymphohematopoietic malignancies. During these years, some authors reported significant associations between lung cancer risk and residential proximity to (a) smelters, (b) complex industrial areas, and (c) other localized emission sources. There was some evidence that leukemia and lymphomas occurred in the neighborhoods that contained industrial sites.     

In Vivo Binding of Topically Applied Human bFGF on Rabbit Corneal Epithelial Wound

Abstract

We present the results of the first evaluation of human placenta extracted basic fibroblast growth factor (bFGF) in a rabbit corneal epithelium wound-healing model. Healing dose-response experiments after selective epithelial wounding with iodine vapors demonstrated that bFGF accelerated the repair process in a saturable manner. Corneal binding of topically applied ¹²⁵I-labeled bFGF was investigated using radioassay and autoradiographic techniques. Basic FGF was shown to bind specifically to denuded epithelial basement membrane in a very stable fashion and not to the intact epithelium. No transfer of the topical bFGF to the aqueous humor or any intraocular structure could be observed. The stability of this interaction was further demonstrated by reextracting and characterizing the labeled factor from treated corneas. The specificity of the fixation was documented by in vivo topical competition with unlabeled bFGF or heparin. We propose that bFGF-basement membrane interactions play a role in corneal wound healing.     

Cell attenuated porcine epidemic diarrhea virus strain Zhejiang08 provides effective immune protection attributed to dendritic cell stimulation

Since 2010, the porcine epidemic diarrhea coronavirus (PEDV) has caused significant damage to the global pork industry. However, classical PEDV vaccine strains only provide limited protection against emerging strains. In this study, we successfully isolated and attenuated the PEDV epidemic strain Zhejiang08, which was characterized by good cell adaptation and high-titer production 48 h post infection in Vero E6 cells. The attenuated virus induced a high level of virus-specific neutralizing antibodies until 120 days after immunization in piglets and provided complete protection when challenged with an emerging virus strain on day 14 post immunization. Moreover, the capability to activate dendritic cells (DCs) of this isolate was identified. Higher expression levels of IL-12 and IFN-γ were recorded in DCs after treatment with Zhejiang08 for 24 h. Furthermore, genome sequencing and phylogenetic analysis revealed high homology between the main antigen epitopes of Zhejiang08 and PEDV pandemic isolates following 2011. Combining the glycosylation site prediction results and their distribution within the spatial structure of the S protein, led to the conclusion that the observed more effective host immune response of Zhejiang08 compared to CV777 was possibly associated with a lack of the potential glycosylation site in the 296 amino acids of the S protein. In summary, we illustrated that the attenuated virus represents a promising vaccine candidate.