Pilot study for assessment of prevalence of intrafamilial hepatitis C transmission in relation to salivary viral load among infected patients with and without chronic renal failure

HCV-RNA in saliva of HCV patients provides a biological basis for its potential transmission. HCV viremia is particularly high in HCV patients on hemodialysis. This study aimed to evaluate the prevalence of HCV in saliva of HCV patients with and without renal failure, and the possible role of intrafamilial transmission of the virus. Twenty HCV patients were enrolled in this study. They were divided into two groups: 10 HCV infected patients without renal failure (Group I) and 10 with renal failure (Group II).  Detection of HCV-RNA by quantitative RT-PCR in serum and saliva of both groups was done. Thirty-eight family members of both groups were included for the detection of serum HCV antibody. The percentage of the saliva-positive patients for HCV was significantly higher in the renal failure group (70%) than the other group (40%) (p<0.05). There was insignificant statistical difference between the two groups as regards infectivity to their family contacts. Also there was insignificant correlation between the level of viremia and the intra familial transmission with a mean + SD (9,33,250 +24,501) in negative relatives and a mean + SD(79,912+26,879) in positive relatives (p> 0.05). But a significant correlation was revealed between the level of viremia and saliva positivity, with a mean + SD(12,95,666 + 1792) in saliva-positive patients and a mean +SD (3,74,465 + 2150) in saliva-negative patients (p< 0.05). There was a highly significant difference between infectivity of HCV saliva-positive patients and saliva-negative patients to their family contacts (p< 0.001). Conclusion: Increased percentage of HCV detection in saliva of HCV patients with renal failure on HD may cause spreading of HCV in HD units among RF patients. Also there was increased percentage of interfamilial infectivity among the saliva-positive patients to their relatives and this suggests that saliva might have an infective role.Keywords: Salivary; HCV; HCV PCR; Intrafamilial transmissio

[3H]Adenine is a suitable radioligand for the labeling of G protein-coupled adenine receptors but shows high affinity to bacterial contaminations in buffer solutions

[3H]Adenine has previously been used to label the newly discovered G protein-coupled murine adenine receptors. Recent reports have questioned the suitability of [3H]adenine for adenine receptor binding studies because of curious results, e.g. high specific binding even in the absence of mammalian protein. In this study, we showed that specific [3H]adenine binding to various mammalian membrane preparations increased linearly with protein concentration. Furthermore, we found that Tris-buffer solutions typically used for radioligand binding studies (50 mM, pH 7.4) that have not been freshly prepared but stored at 4°C for some time may contain bacterial contaminations that exhibit high affinity binding for [3H]adenine. Specific binding is abolished by heating the contaminated buffer or filtering it through 0.2-μm filters. Three different, aerobic, gram-negative bacteria were isolated from a contaminated buffer solution and identified as Achromobacter xylosoxidans, A. denitrificans, and Acinetobacter lwoffii. A. xylosoxidans, a common bacterium that can cause nosocomial infections, showed a particularly high affinity for [3H]adenine in the low nanomolar range. Structure–activity relationships revealed that hypoxanthine also bound with high affinity to A. xylosoxidans, whereas other nucleobases (uracil, xanthine) and nucleosides (adenosine, uridine) did not. The nature of the labeled site in bacteria is not known, but preliminary results indicate that it may be a high-affinity purine transporter. We conclude that [3H]adenine is a well-suitable radioligand for adenine receptor binding studies but that bacterial contamination of the employed buffer solutions must be avoided

Physiological and biochemical parameters: new tools to screen barley root exudates allelopathic potential (*Hordeum vulgare* L. subsp. *vulgare*

peer reviewedMorphological markers/traits are often used in the detection of allelopathic stress, but optical signals including chlorophyll a fluorescence emission could be useful in developing new screening techniques. In this context, the allelopathic effect of barley (Hordeum vulgare subsp. vulgare) root exudates (three modern varieties and three landraces) were assessed on the morphological (root and shoot length, biomass accumulation), physiological (Fv/Fm and F0), and biochemical (chlorophyll and protein contents) variables of great brome (Bromus diandrus Roth., syn. Bromus rigidus Roth. subsp. gussonii Parl.). All the measured traits were affected when great brome was grown in a soil substrate in which barley plants had previously developed for 30 days before being removed. The response of receiver plants was affected by treatment with activated charcoal, dependent on barley genotype and on the nature of the growing substrate. The inhibitory effect was lower with the addition of the activated charcoal suggesting the release of putative allelochemicals from barley roots into the soil. The barley landraces were more toxic than modern varieties and their effect was more pronounced in sandy substrate than in silty clay sand substrate. In our investigation, the chlorophyll content and Fv/Fm were the most correlated variables with barley allelopathic potential. These two parameters might be considered as effective tools to quantify susceptibility to allelochemical inhibitors in higher plants