The effect of Ge, Si and Sn phthalocyanine photosensitizers on cell proliferation and viability of human oesophageal carcinoma cells

The photodynamic activity of water soluble mixed sulfonated metallophthalocyanines complexes: GePcSmix, SnPcSmix and SiPcSmix on human oesophageal carcinoma (SNO) cells are reported, and compared with the activity of the unmetallated H2PcSmix and of the newly synthesized water soluble adjacently substituted binaphthalo phthalocyanine (complex 3). The alkaline phosphate (ALP) showed damage to the cell membrane in the presence of complex 3 without irradiation. The GePcSmix complex caused a relatively large increase in inflammation and a high intracellular ATP

Vitamin D as an Adjunctive Therapy in Asthma. Part 1: A Review of Potential Mechanisms

Vitamin D deficiency (VDD) is highly prevalent worldwide. The classical role for vitamin D is to regulate calcium absorption form the gastrointestinal tract and influence bone health. Recently vitamin D receptors and vitamin D metabolic enzymes have been discovered in numerous sites systemically supporting diverse extra-skeletal roles of vitamin D, for example in asthmatic disease. Further, VDD and asthma share several common risk factors including high latitude, winter season, industrialization, poor diet, obesity, and dark skin pigmentation. Vitamin D has been demonstrated to possess potent immunomodulatory effects, including effects on T cells and B cells as well as increasing production of antimicrobial peptides (e.g. cathelicidin). This immunomodulation may lead to asthma specific clinical benefits in terms of decreased bacterial/viral infections, altered airway smooth muscle-remodeling and efunction as well as modulation of response to standard anti-asthma therapy (e.g. glucocorticoids and immunotherapy). Thus, vitamin D and its deficiency have a number of biological effects that are potentially important in altering the course of disease pathogenesis and severity in asthma. The purpose of this first of a two-part review is to review potential mechanisms whereby altering vitamin D status may influence asthmatic disease

Hsp70 induction and hsp70 gene polymorphisms as indicators of acclimatization under hyperthermic conditions.

Acclimatization is a process which occurs as a result of repeated mild increases in core temperature, which allows an organism to carry out increased work in the heat due to better heat dissipation (Moseley, 1997). In order to prevent the occurrence of heat illness, it is necessary for individuals who perform work in hot, humid environments to undergo acclimatization. Exposure to different types of stimuli, such as heat exercise and oxidative stress, results in the formation of proteins in the cells which are known as heat shock protein (HSP) (Powers et al, 2001). The main function of HSP is to act as molecular chaperones. Specifically, the 70 kDa HSP, known as Hsp70, play an important part in cellular protection and adaptation during and following exposure to stressful events. Two prominent members of the Hsp70 family are Hsp72, which is the inducible form of Hsp70, and Hsp73, which is the constitutively synthesized form of the protein. Acquisition of thermotolerance in vitro in Chinese hamster fibroblast cells is accompanied by increased Hsp72 levels during a heating episode, indicating that Hsp72 tends to target proteins which have been damaged by a stress situation more than Hsp73 (Li and Werb, 1982). A number of different hsp70 genes are found, which include hsp70-1, hsp70-2 (3¢utr and pst I) and hsp70-hom (Milner and Campbell, 1990). Both the hsp70-1 and hsp70-2 genes encode the primary heat-induced Hsp70 protein as an identical protein product (Hunt and Morimoto, 1985). Following heat shock, no increase in the hsp70-hom mRNA levels is observed (Milner and Campbell, 1990). The use of the Hsp70 protein and hsp70 gene polymorphisms as markers of acclimatization were investigated by subjecting twenty-two individuals to exercise in a hot, humid environment. These individuals were exposed to an initial heat stress, where they participated in a step test at an external work rate of 70 W, followed by participation in an acclimatization program which involved exercising at various combinations of 35 W and 70 W of the external work rate. After acclimatization, the individuals were exposed to a second heat stress, identical to the initial heat stress. The Hsp70 levels both before and after acclimatization were determined in response to heat stress in blood serum by means of the StressXpress ELISA Kit (Stressgen Biotechnologies) and in human monocytes by means of Western blots, using a mouse antiñHsp70 monoclonal primary antibody (Stressgen Biotechnologies) and a goat antiñmouse IgG (H+L) peroxidase conjugated secondary antibody. The hsp70 gene polymorphisms were determined by means of polymerase chain reaction (PCR), using primers specific to the hsp70-1, hsp70-2 (3¢utr), pst I and hsp70-hom genes, so that the genotype combinations for each individual were determined. Blood type was also assessed. It was found that the basal serum Hsp70 levels in individuals who exhibited the ability to acclimatize decreased in response to the acclimatization program, which allowed more Hsp70 to be induced in response to the second heat stress compared to the initial heat stress. The individuals who were unable to acclimatize showed increased basal serum Hsp70 levels in response to acclimatization, which prevented these individuals from inducing high Hsp70 levels in response to the second heat stress. The Hsp70 induced in the monocytes during this program followed the same pattern in both the individuals able to acclimatize and those who were unable to acclimatize, and can therefore not be used as a marker of acclimatization. For the female participants, the current menstrual phase of each woman had to be taken into account, as this had an affect on the core temperature and therefore influenced the division of the female participants into their respective groups. These were the group of individuals who demonstrated the ability to acclimatize or the group of individuals who were unable to acclimatize. The use of oral contraceptives also had to be taken into account, as this too had an influence on the core temperature and therefore also affected the division of the individuals into the group who demonstrated the ability to acclimatize or those who were unable to acclimatize. Cyclic changes during the menstrual cycle may have also changed the Hsp profile. Regarding the hsp70 gene polymorphisms, the A/A, P2 P2 and A1 A1 genotype combination was not present in any of the individuals who were unable to acclimatize, however six of the individuals who showed the ability to acclimatize possessed this genotype combination. The level of induced Hsp70 levels present in the serum of individuals able to acclimatize and the presence or absence of the A/A, P2 P2 and A1 A1 genotype combination therefore have the potential to be used as markers of acclimatization.Dr. M. Cronj

A novel multiplex real-time RT-PCR assay with FRET hybridization probes for the detection and quantitation of 13 respiratory viruses

Quantitative multiplex real-time RT-PCR assays utilizing fluorescence resonance energy transfer (FRET) hybridization probes were developed for the detection of 13 respiratory viruses, including well recognized viral causes (respiratory syncytial virus, influenza viruses A and B, parainfluenza viruses types 1, 2, and 3, adenovirus) as well as viruses described recently as causes of acute respiratory tract infections (human coronaviruses NL63, HKU1, 229E, and OC43, human bocavirus, and human metapneumovirus). FRET probes have an improved toleration for single base mismatches than other probe chemistries, reducing the chances of missing highly variable RNA viruses. The assay could detect 2.5–25 DNA/RNA copies/μl (2.5 × 103–2.5 × 104 copies/ml). Validation on 91 known positive respiratory specimens indicated similar specificity as commercial direct immunofluorescence assays (IFA) or single-round PCRs used in initial identification. Screening of 270 IFA negative respiratory specimens identified new viruses in 40/270 (14.8%) cases and additional 79/270 (29.3%) well recognized viruses missed by routine diagnostic assays including 6.7% co-infections. All viruses could be detected in the clinical screening panel. The assays demonstrates an improved sensitivity and scope of detecting respiratory viruses relative to routine antigen detection assays while the quantitative utility may facilitate investigation of the role of co-infections and viral load in respiratory virus pathogenesis.This study has been funded by the Poliomyelitis Research Foundation

Hsp70 induction and hsp70 gene polymorphisms as indicators of acclimatization under hyperthermic conditions

The possibility of using Hsp70 and hsp70 gene polymorphisms as markers of acclimatization was investigated. Volunteers (22) were subjected to an acclimatization regimen and blood analysed for Hsp70 (Hsp72) and hsp70 polymorphisms before and after a heat tolerance test. Physiological parameters denoting acclimatization, or not, were correlated to levels of Hsp70 and combination of hsp70 genes. Only individuals that acclimatized had decreased basal Hsp70 levels and increased ability to induce Hsp70 together with a specific hsp70 genotype combination. We propose that Hsp70 levels (basal vs. induced) with the genotype combination have the potential to be used as markers of acclimatization.National Research Foundation of SA and the Walker Fund of Faculty of Science, UJ for financial assistance

Confirmation of an Association Between Single Nucleotide Polymorphisms in the VDR Gene With Respiratory Syncytial Virus Related Disease in South African Children

Respiratory syncytial virus is a leading cause of lower respiratory tract infection in infants. Disease severity has been linked to host immune responses and polymorphisms in genes associated with innate immunity. A large-scale genetics study of single nucleotide polymorphisms (SNPs) in children in the Netherlands identified SNPs in the vitamin D receptor (VDR) and JUN genes which have a strong association with an increased risk of developing bronchiolitis following the first respiratory syncytial virus (RSV) infection. The Toll-like receptor 4 (TLR4) gene has two SNPs which have been associated previously with RSV disease severity in various populations. The aim of this study was to determine if these SNPs may be associated with RSV disease in African children in South Africa. RSV patient (n = 296) and control (n = 113) groups were established (median ages: 3 and 3.5 months) and DNA extracted from the collected specimens. Real-time polymerase chain reaction using hydrolysis probes was used to screen for SNPs in the VDR (Thr1Meth; rs10735810), TLR4 (Asp299Gly; rs4986790 and Thr399lle; rs4986791) and JUN (c.750G/A; rs11688) genes. Carriers of the VDR (Thr1Meth) SNP minor T allele were more prone to RSV disease than individuals in the control group. The TLR4 (Asp299Gly), TLR4 (Thr399lle), and JUN (c.750G/A) SNPs showed no significant association with RSV disease. It is concluded that children carrying the minor T allele of the VDR (Thr1Meth) SNP may be predisposed to RSV disease, as this SNP was identified as a risk factor for severe RSV disease in South African children, confirming the findings in the Netherlands. J. Med. Virol. 83:18341840, 2011. (C) 2011 Wiley-Liss, Inc

Viral etiology of severe pneumonia among Kenyan infants and children

Context Pneumonia is the leading cause of childhood death in sub-Saharan Africa. Comparative estimates of the contribution of causative pathogens to the burden of disease are essential for targeted vaccine development. Objective To determine the viral etiology of severe pneumonia among infants and children at a rural Kenyan hospital using comprehensive and sensitive molecular diagnostic techniques. Design, Setting, and Participants Prospective observational and case-control study during 2007 in a rural Kenyan district hospital. Participants were children aged 1 day to 12 years, residing in a systematically enumerated catchment area, and who either were admitted to Kilifi District Hospital meeting World Health Organization clinical criteria for severe pneumonia or very severe pneumonia; (2) presented with mild upper respiratory tract infection but were not admitted; or (3) were well infants and children attending for immunization. Main Outcome Measures The presence of respiratory viruses and the odds ratio for admission with severe disease. Results Of 922 eligible admitted patients, 759 were sampled (82% [median age, 9 months]). One or more respiratory viruses were detected in 425 of the 759 sampled (56% [95% confidence interval {CI}, 52%-60%]). Respiratory syncytial virus (RSV) was detected in 260 participants (34% [95% CI, 31%-38%]) and other respiratory viruses were detected in 219 participants (29%; 95% CI, 26%-32%), the most common being Human coronavirus 229E (n=51 [6.7%]), influenza type A (n=44 [5.8%]), Parainfluenza type 3 (n=29 [3.8%]), Human adenovirus (n=29 [3.8%]), and Human metapneumovirus (n=23 [3.0%]). Compared with well control participants, detection of RSV was associated with severe disease (5% in control participants; adjusted odds ratio, 6.11 [95% CI, 1.65-22.6]) while collectively, other respiratory viruses were not associated with severe disease (23% in control participants; adjusted odds ratio, 1.27 [95% CI, 0.64-2.52]). Conclusion In a sample of Kenyan infants and children admitted with severe pneumonia to a rural hospital, RSV was the predominant viral pathogen. JAMA. 2010;303(20):2051-2057 www.jama.co