An analysis of red cell enzymatic markers in the province of Bologna (Italy).

About 280 unrelated individuals living in the province of Bologna (Northern Italy) have been studied for the following red cell enzymatic markers: phosphoglucomutase (PGM), adenylate kinase (AK), adenosine deaminase (ADA) and phosphohexose isomerase (PHI). 116 subjects from the same sample have also been analysed for red cell acid phosphatase (ACP). The observed gene frequencies are PGM21 = 0.280; AK2 = 0.030; ADA2 = 0.091; ACPa = 0.297; ACPb = 0.647; ACPc = 0.056. In the PHI system two individuals with the variant PHI 3-1 phenotype have been found.     

Subtyping of human red cell phosphoglucomutase locus 1 (PGM1) polymorphism: a third PGM1(1) allele common among Twa Pygmies from North Rwanda.

Seventy-eight Twa Pygmies from North Rwanda have been subtyped by acid starch gel electrophoresis for the polymorphism at the phosphoglucomutase locus 1 (PGM1). A third common PGM1(1) allele that has been named PGM1(1Twa) was detected in heterozygous association with both PGM1(1S) and PGM1(1F) alleles. The PGM1(1Twa) product is faster than those of the other two PGM1(1) alleles and has the same electrophoretic mobility as the rare PGM1(6) enzyme. The frequency of PGM1(1Twa) was found to be 0.45.     

Orthologous gene-expression profiling in multi-species models: search for candidate genes

Microarray-driven gene-expression profiles are generally produced and analyzed for a single specific experimental model. We have assessed an analytical approach that simultaneously evaluates multi-species experimental models within a particular biological condition using orthologous genes as linkers for the various Affymetrix microarray platforms on multi-species models of ventilator-associated lung injury. The results suggest that this approach may be a useful tool in the evaluation of biological processes of interest and selection of process-related candidate genes.     

Physiological Heterothallism and Sexuality in Euascomycetes: A Partial History

Copyright 1998 Academic Press.     

Inheritance of rDNA spacer length variants in man

Summary We studied the rDNA spacer length polymorphism in a sample of 121 individuals belonging to families of 2–3 generations. Our data, obtained by restriction pattern analysis of genomic DNA, confirmed the limited and discrete nature of this polymorphism. Using the pattern as a genetic marker, we analyzed the segregation of length variants in the different families and we investigated the possible occurrence of unequal crossing-over events among homologous and nonhomologous rDNA clusters. No direct evidence of recombination in the spacer region that we analyzed emeged from our study. All the differences in the restriction patterns observed among individuals from the same family could be explained as resulting from meiotic segregation. Family data showed a multichromosomal distribution of NTS length variants and demonstrated a direct correspondence between the frequency of a variant in the population and its degree of spreading on the different rDNA clusters.     

Cytokine gene polymorphisms in gastric cancer patients from two Italian areas at high and low cancer prevalence

Polymorphisms of interleukin-1beta (IL-1beta), IL-1 receptor antagonist (IL1-RN), and tumor necrosis factor-alpha (TNF-alpha) genes are supposed to be key determinants of gastric cancer risk. Our aim was to study the association between these polymorphisms and gastric cancer in two areas characterized by high (Pavia/Bologna, North Italy) and low (San Giovanni Rotondo, South Italy) gastric cancer prevalence. Genomic DNA was obtained from 216 healthy donors and 98 gastric cancer patients from Pavia and Bologna, and 146 healthy donors and 86 gastric cancer patients from San Giovanni Rotondo. Two SNP in IL-1beta (-511 C/T) and TNF-alpha (-308 G/A) as well as the VNTR polymorphism of IL-1RN locus were studied. A significant linkage disequilibrium was found between IL-1beta -511 and IL-1RN. Genotype and allele frequencies at the IL-1beta, IL-1RN, and TNF-alpha loci in gastric cancer cases were not significantly different from controls. An epistatic effect between IL-1beta -511 and IL-1RN was found with the IL-1beta -511C/IL-1RN*2 haplotype conferring a significant protection against the intestinal-type of gastric cancer in the Southern population. In conclusion, IL-1beta, IL1-RN, and TNF-alpha genotypes are not associated with gastric cancer in Italian patients. An epistatic interrelationship between IL-1beta -511 and IL-1RN confers protection against gastric cancer in low-risk Italian population.     

Somatic frameshift mutations in the Bloom syndrome BLM gene are frequent in sporadic gastric carcinomas with microsatellite mutator phenotype

Background  

Genomic instability has been reported at microsatellite tracts in few coding sequences. We have shown that the Bloom syndrome BLM gene may be a target of microsatelliteinstability (MSI) in a short poly-adenine repeat located in its coding region. To further characterize the involvement of BLM in tumorigenesis, we have investigated mutations in nine genes containing coding microsatellites in microsatellite mutator phenotype (MMP) positive and negative gastric carcinomas (GCs).     

Electrophoretic subtyping of phosphoglucomutase locus 1 (PGM1) polymorphism in the Italian and Czechoslovakian populations

About 3,500 subjects from Italy and Czechoslovakia have been analyzed by acid starch gel electrophoresis for the subtyping of PGM1 polymorphism. The Italian sample included three different subgroups, from Northern, Central and Southern Italy. The allele frequencies found in the three groups do not differ significantly from each other; the observed values in the pooled sample are: PGM1S1 = 0.594, PGM1F1 = 0.118, PGM2S1 = 0.231, PGM2F1 = 0.057. In the Czechoslovakian group, which differs significantly from the Italian population, the following allele frequencies were found: PGM1S1 = 0.639, PGM1F1 = 0.118, PGM2S1 = 0.180, PGM2F1 = 0.063. The analysis of 217 families did not show any exception to Mendelian inheritance of the patterns.     

Functional analysis of MUTYH mutated proteins associated with familial adenomatous polyposis

The MUTYH DNA glycosylase specifically removes adenine misincorporated by replicative polymerases opposite the oxidized purine 8-oxo-7,8-dihydroguanine (8-oxoG). A defective protein activity results in the accumulation of G > T transversions because of unrepaired 8-oxoG:A mismatches. In humans, MUTYH germline mutations are associated with a recessive form of familial adenomatous polyposis and colorectal cancer predisposition (MUTYH-associated polyposis, MAP). Here we studied the repair capacity of the MUTYH variants R171W, E466del, 137insIW, Y165C and G382D, identified in MAP patients. Following expression and purification of human proteins from a bacterial system, we investigated MUTYH incision capacity on an 8-oxoG:A substrate by standard glycosylase assays. For the first time, we employed the surface plasmon resonance (SPR) technology for real-time recording of the association/dissociation of wild-type and MUTYH variants from an 8-oxoG:A DNA substrate. When compared to the wild-type protein, R171W, E466del and Y165C variants showed a severe reduction in the binding affinity towards the substrate, while 137insIW and G382D mutants manifested only a slight decrease mainly due to a slower rate of association. This reduced binding was always associated with impairment of glycosylase activity, with adenine removal being totally abrogated in R171W, E466del and Y165C and only partially reduced in 137insIW and G382D. Our findings demonstrate that SPR analysis is suitable to identify defective enzymatic behaviour even when mutant proteins display minor alterations in substrate recognition.     

Expression of Toll-like receptor 2 is up-regulated in monocytes from patients with chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is characterised by pulmonary and systemic inflammation which flare-up during episodes of acute exacerbation (AECOPD). Given the role of Toll-like receptors (TLRs) in the induction of inflammatory responses we investigated the involvement of TLRs in COPD pathogenesis.

Methods

The expression of TLR-2, TLR-4 and CD14 in monocytes was analyzed by flow cytometry. To study the functional responses of these receptors, monocytes were stimulated with peptidoglycan or lipopolysaccharide and the amounts of TNFα and IL-6 secreted were determined by ELISA.

Results

We found that the expression of TLR-2 was up-regulated in peripheral blood monocytes from COPD patients, either clinically stable or during AECOPD, as compared to never smokers or smokers with normal lung function. Upon stimulation with TLR-2 ligand monocytes from COPD patients secreted increased amounts of cytokines than similarly stimulated monocytes from never smokers and smokers. In contrast, the expressions of TLR-4 and CD14 were not significantly different between groups, and the response to lipopolysaccharide (a TLR-4 ligand) stimulation was not significantly different either. At discharge from hospital TLR-2 expression was down-regulated in peripheral blood monocytes from AECOPD patients. This could be due to the treatment with systemic steroids because, in vitro, steroids down-regulated TLR-2 expression in a dose-dependent manner. Finally, we demonstrated that IL-6, whose plasma levels are elevated in patients, up-regulated in vitro TLR-2 expression in monocytes from never smokers.

Conclusion

Our results reveal abnormalities in TLRs expression in COPD patients and highlight its potential relationship with systemic inflammation in these patients.