Radioiodination and bioevaluation of nitrofurantoin for urinary tract imaging

Nitrofurantoin (NF) was labeled with iodine‐125 via electrophilic substitution reaction. Some factors affecting the radiochemical yield of ¹²⁵I‐NF, such as NF concentration, chloramine‐T (CAT) concentration, pH of the reaction mixture, reaction time, temperature, and reaction medium, were studied. The maximum yield of ¹²⁵I‐NF (90%) was obtained by using 3.7 MBq of Na¹²⁵I, 1 mM CAT, 1 mM NF in DMF, at pH 2 and 60 °C within 5 min. The specific activity of ¹²⁵I‐NF reaches 33.3 MBq/0.2 mmol, and the ¹²⁵I‐NF was completely separated and purified by means of high pressure liquid chromatography. The biological distribution in normal mice indicates the suitability of radioiodinated NF for urinary tract imaging. Copyright © 2012 John Wiley & Sons, Ltd.     

Does JC virus have a role in the etiology and prognosis of Egyptian colorectal carcinoma?

John Cunningham virus (JCV) encodes an oncogenic T‐antigen, which is capable of interacting with key growth regulatory pathways. JCV definite role as causal agent of human cancer, still awaits final confirmation. The present study was conducted to assess the possible role of JCV in Egyptian colorectal carcinoma (CRC) and correlate the expression with the clinicopathological features and survival. JCV in situ hybridization (ISH) signals and large T antigen immunoreactivity were examined in 87 colonic specimens. Positive glandular JCV ISH signals were detected in 20%, 25% and 40% of normal, adenoma and CRC cases respectively. Stromal JCV ISH signals were identified in 26% of CRC cases and 5% of adenoma however, normal mucosa did not show stromal positivity with significant difference (p = 0.03). Glandular JCV expression was significantly associated with high grade (p = 0.03), high mitotic index (p=0.02) and low apoptotic index (p = 0.00). Positive stromal signals were significantly associated with low apoptosis (p = 0.00). No positive nuclear immunostaining of JCV large T antigen was detected in all specimens. JCV stromal expression was the 2nd most powerful indicator of short survival and bad prognosis (p = 0.03) in CRC patients. JCV might play an etiological role in CRC tumorogenesis and short survival in Egyptian CRC patients.     

Molecular cloning and characterization of peroxiredoxin 4 involved in protection against oxidative stress in the silkworm Bombyx mori

Peroxiredoxins (Prxs) are a ubiquitous family of proteins that play important roles in insects in protection against oxidative stress through the detoxification of cellular peroxides. Here, we describe the cloning and characterization of a Prx4 cDNA of the silkworm Bombyx mori (BmPrx4). The BmPrx4 gene has an open reading frame of 744 bp encoding 248 amino acids and a conserved motif, VCP, involved in its presumed redox functions. The heterologously expressed proteins of the gene in Escherichia coli showed antioxidant activity, removed hydrogen peroxide and protected DnA. Western blotting analysis showed the presence of BmPrx4 in the haemolymph, suggesting that the protein is secretable. Moreover, BmPrx4 was expressed at all developmental stages. The expression level of BmPrx4 was relatively low during the feeding stage but high at the wandering stage. BmPrx4 was induced by quercetin or temperature stress. Immunohistochemical analysis revealed that BmPrx4 is present in the brain, neurones and olfactory organ of the head in silkworms. Overall, our results indicate that the expression profile of BmPrx4 correlates well with protection from oxidative damage. Our data provide clues for the development of control technology for agricultural and forestry pests as the silkworm is a representative of lepidopteran pests.     

Evolution of Helicobacter pylori susceptibility to antibiotics during a 10‐year period in Lithuania

The study evaluated the changes in the prevalence of Helicobacter pylori strains with primary resistance to antibiotics during the last 10 years in Lithuania. H. pylori susceptibilities to antibiotics were tested in 89 patients in 1998, in 81 patients in 2001 and in 90 patients in 2007/2008. Susceptibility to metronidazole, clarithromycin, amoxicillin and tetracycline was tested using E‐test or agar dilution method. Susceptibility to ciprofloxacin was only tested in 2007/2008. Data about utilization of all authorized and available on market macrolides and clindamycin in Lithuania during 2003–2007 were evaluated using WHO ATC/DDD methodology. A total of 260 H. pylori strains cultured from untreated adult patients were investigated. Primary resistance rates (1998, 2001 and 2007/2008) for metronidazole were 24.7%, 33.3%, and 35.6%, for clarithromycin 1.1%, 3.7%, and 3.3% and for tetracycline 0%, 2.5% and 0% respectively. No cases of amoxicillin resistance have been detected. The resistance rate for ciprofloxacin was 5.6% in 2007/2008. Data of total macrolides and clarithromycin utilization in Lithuania revealed that despite an increase of consumption of these drugs in Lithuania during 2003–2007 in 1.5 times, the total macrolide consumption remains one of the lowest in Europe. We have not observed any significant changes in the susceptibility of H. pylori to the most widely used antibiotics during the recent 10‐year period. The low resistance rate to clarithromycin might be related to the policy to avoid use of macrolides as first‐line treatment for pulmonary and other infections.