Assessing the clinical utility of Wnt pathway markers in colorectal cancer.

PURPOSE: ß-catenin and AXIN2 play an important role in the Wnt signaling pathway. The aim of this study was to investigate ß-catenin and AXIN2 expression in colorectal cancer (CRC) and relate these findings with patients' clinicopathological features and prognosis. METHODS: 57 consecutive patients with surgically treated CRC were included in this study. Quantitative PCR and immunohistochemistry (IHC) analyses were performed to characterize the expression of the aforementioned markers in CRC tissues. RESULTS: ß-catenin overexpression in the nucleus was associated with advanced N stage CRCs (p=0.04). Multivariate Cox regression analysis showed that ß-catenin overexpression is an independent prognostic factor for overall survival (OS). A positive correlation between ß-catenin location and AXIN2 mRNA was observed. CONCLUSIONS: Nuclear ß-catenin is a valuable prognostic factor. AXIN2 is a component of the "Destruction Complex" and also a Wnt target gene. However, the clinical importance of AXIN2 expression in CRC remains unclear.

West Nile Virus Circulation in Mosquitoes in Greece (2010-2013).

Background of the Study. Following a large West Nile virus (WNV) epidemic in Northern Greece in 2010, an active mosquito surveillance system was implemented, for a 3-year period (2011, 2012, and 2013). Description of the Study Site and Methodology. Using mainly CO2 mosquito traps, mosquito collections were performed. Samples were pooled by date of collection, location, and species and examined for the presence of WNV. Results. Positive pools were detected in different areas of the country. In 2010, MIR and MLE values of 1.92 (95% CI: 0.00-4.57) and 2.30 (95% CI: 0.38-7.49) were calculated for the Serres Regional Unit in Central Macedonia Region. In 2011, the highest MIR value of 3.71(95% CI: 1.52-5.91) was recorded in the Regions of Central Greece and Thessaly. In 2012, MIR and MLE values for the whole country were 2.03 (95% CI: 1.73-2.33) and 2.15 (95% CI: 1.86-2.48), respectively, for Cx. pipiens. In 2013, in the Regional Unit of Attica, the one outbreak epicenter, MIR and MLE values for Cx. pipiens were 10.75 (95% CI: 7.52-13.99) and 15.76 (95% CI: 11.66-20.65), respectively. Significance of Results/Conclusions. The contribution of a mosquito-based surveillance system targeting WNV transmission is highlighted through the obtained data, as in most regions positive mosquito pools were detected prior to the date of symptom onset of human cases. Dissemination of the results on time to Public Health Authorities resulted in planning and application of public health interventions in local level.

Detection and species identification of Old World Leishmania in clinical samples using a PCR-based method.

The aim of this study was to develop a simple, low-cost method for the detection and species differentiation of Leishmania directly from clinical samples, for routine use in a parasitology laboratory. A total of 87 samples was used, including 60 peripheral blood, seven bone marrow and 17 skin lesion material samples, derived from Greek patients with visceral or cutaneous leishmaniasis, and three reference strains. PCR was performed using primers designed to amplify the internal transcribed spacer 1 (ITS1) region of the rRNA gene. Identification of the Leishmania species studied was achieved by digestion with a single restriction endonuclease (RFLP), single-strand conformational polymorphism (SSCP) and DNA sequencing of the PCR-generated fragments. Typing identified all visceral and one cutaneous leishmaniasis strains as L. infantum, twelve of the cutaneous leishmaniasis strains as L. tropica and four as L. major. The described PCR method proved efficient for the detection of pathogenic Leishmania species in various clinical samples, most importantly in peripheral blood samples. Furthermore, PCR followed by a simple RFLP using a single restriction endonuclease was capable of identifying all Leishmania species commonly encountered in Greece.

Direct detection of Blastocystis sp. in human faecal samples and subtype assignment using single strand conformational polymorphism and sequencing.

Blastocystis is an anaerobic parasitic microorganism, which has been found in the intestinal tract of many vertebrates including humans. Recently, members of Blastocystis sp. were classified into nine subtypes, based on phylogenetic trees derived from sequence analysis of the small subunit ribosomal RNA (SSU rRNA) gene. The role of Blastocystis in human disease remains uncertain and the existence of pathogenic and non-pathogenic subtypes is under investigation. We report the development of a polymerase chain reaction (PCR)-based assay that is able to detect Blastocystis directly from human faeces. Furthermore, combined with single strand conformational polymorphism (SSCP) analysis and/or sequencing of the respective PCR product, the protocol can classify Blastocystis among the nine established subtypes. The method was applied to 45-positive and 30-negative faecal samples and proved to be highly sensitive and specific. Genotyping using SSCP analysis and sequencing revealed that subtype 3 is the most frequent in Greece, while subtypes 1, 2, 4, 6 and 7 are also present but in lower frequencies. Hopefully, the simplicity of the proposed method will contribute toward large-scale epidemiological studies for prompt clarification of the role of the parasite.

Association study of human VN1R1 pheromone receptor gene alleles and gender.

Pheromones are water-soluble chemicals that elicit neuroendocrine and physiological changes, while they also provide information about gender within individuals of the same species. VN1R1 is the only functional pheromone receptor in humans. We have undertaken a large mutation screening approach in 425 adult individuals from the Hellenic population to investigate whether the allelic differences, namely alleles 1a and 1b present in the human VN1R1 gene, are gender specific. Here we show that both VN1R1 1a and 1b alleles are found in chromosomes of both male and female subjects at frequency of 26.35% and 73.65%, respectively. Given the fact that those allelic differences potentially cause minor changes in the protein conformation and its transmembrane domains, as simulated by the TMHMM software, our data suggest that the allelic differences in the human VN1R1 gene are unlikely to be associated with gender and hence to contribute to distinct gender-specific behavior.

Increased gamma-globin gene expression in beta-thalassemia intermedia patients correlates with a mutation in 3'HS1.

We report a novel set of genetic markers in the DNaseI hypersensitive sites comprising the human beta-globin locus chromatin hub (CH), namely HS-111 and 3'HS1. The HS-111 (-21 G>A) and 3'HS1 (+179 C>T) transitions form CH haplotypes, which occur at different frequencies in beta-thalassemia intermedia and major patients and normal (nonthalassemic) individuals. We also show that the 3'HS1 (+179 C>T) variation results in a GATA-1 binding site and correlates with increased fetal hemoglobin production in beta-thalassemia intermedia patients. In contrast, the HS-111 (+126 G>A) transition, found in three normal chromosomes, is simply a rare polymorphism. We conclude that the CH haplotypes are useful genetic determinants for beta-thalassemia major and intermedia patients, while the 3'HS1 (+179 C>T) mutation may have functional consequences in gamma-globin genes expression.

Mutation screening in the human epsilon-globin gene using single-strand conformation polymorphism analysis.

The human epsilon-globin gene is necessary for primitive human erythropoiesis in the yolk sac. Herein we report a non-radioactive single-strand conformation polymorphism (SSCP) approach to screen the human epsilon-globin gene and its regulatory regions for possible mutations and single-nucleotide polymorphisms in normal adult subjects, in order to determine those genomic regions, which are not necessary for its proper regulation and function. We identified no sequence variations apart from the expected 5'epsilon /HincII polymorphism in the fragments analyzed, suggesting that genomic alterations in the epsilon-globin gene are most likely incompatible with normal erythropoiesis and proper embryonic development.

Effect of 4 weeks of basic military training on peripheral blood leucocytes and urinary excretion of catecholamines and cortisol.

In this study, we assessed the effects of a 4 week basic military physical training programme for male recruits of the Hellenic Air Force on the number and distribution of circulating immune cells and adrenergic and adrenocortical hormonal responses. One group of recruits (exercised, n = 48) participated in moderate intermittent physical exercise, whereas a second group (non-exercised controls, n = 9) performed only light work in the barracks. Both groups participated in the same non-physical, classroom-type training and testing. Military training by the exercised group resulted in significant increases in CD4+ T-lymphocytes, renal cortisol excretion and the urinary noradrenaline/adrenaline ratio, together with reductions in neutrophils and the neutrophil/lymphocyte ratio. In the exercised group, the urinary noradrenaline/adrenaline ratio correlated positively with the training-induced changes in CD4+ T-lymphocytes and negatively with changes in the neutrophil/lymphocyte ratio. No significant relationship was found between training-induced increases in cortisol excretion and any of the peripheral blood cell alterations. Our results indicate that 4 weeks of military training consisting of intermittent moderate exercise resulted in a significant increase in CD4+ T-lymphocytes and reduction in neutrophils. These changes were probably driven by alterations in hormonal status, including the significant impact of sympathetic nervous system activation.

Rapid molecular identification of Neisseria meningitidis isolates using the polymerase chain reaction followed by single-stranded conformation polymorphism analysis.

Typing of Neisseria meningitidis strains is currently performed with conventional and molecular methods. Our objectives were: first, to develop a polymerase chain reaction (PCR) followed by single-stranded conformation polymorphism (SSCP) analysis of the PorA gene (VR1 region) to distinguish N. meningitidis subtypes and second, to evaluate the method for the identification and characterization of N. meningitidis in patient specimens. SSCP analysis of the VR1 region of the PorA1/2 gene from 126 N. meningitidis strains and 29 clinical samples identified seven SSCP types (SP-1 to SP-7); four strains were not typeable by the method. Classification according to the SSCP methods and serosubtype agreed for 122 of the 126 typeable strains (96.8%). For the 24-culture positive clinical samples, serosubtype and SSCP agreed in all cases. Five samples, which were culture-negative but obtained from children during an apparent outbreak of meningococcal disease in a primary school, presented identical SSCP classification for each sample (SP-2). PCR-SSCP is a rapid and cost-effective method for typing N. meningitidis strains that could provide important early information in the surveillance of suspected meningococcal outbreaks, particularly when culture-negative specimens constitutes the main source of material to analyze.