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Tooth agenesis is one of the most common dental anomalies, with a complex and not yet fully elucidated aetiology. Given the crucial role of the Wnt signalling pathway during tooth development, the purpose of this study was to determine whether nucleotide variants of genes encoding components of this signalling pathway might be associated with hypodontia and oligodontia in the Polish population. A set of 34 single nucleotide polymorphism (SNPs) in 13 WNT and WNT-related genes were analyzed in a group of 157 patients with tooth agenesis and a properly matched control group (n = 430). In addition, direct sequencing was performed to detect mutations in the MSX1, PAX9 and WNT10A genes. Both single-marker and haplotype analyses showed highly significant association between SNPs in the WNT10A gene and the risk for tooth agenesis. Moreover, nine pathogenic mutations within the coding region of the WNT10A gene were identified in 26 out of 42 (62%) tested patients. One novel heterozygous mutation was identified in the PAX9 gene. Borderline association with the risk of non-syndromic tooth agenesis was also observed for the APC, CTNNB1, DVL2 and WNT11 polymorphisms. In conclusion, nucleotide variants of genes encoding important components of the Wnt signalling pathway might influence the risk of tooth agenesis.

The wingless-type MMTV integration site family (Wnt) signalling pathway plays a crucial role in craniofacial development. Recently, nucleotide variants in WNT genes have been shown to be associated with oral congenital anomalies, including facial clefts. Therefore, in the current study we decided to assay the association of nucleotide variants in selected WNT genes with the risk of non-syndromic cleft lip with or without cleft palate (NCL/P) in the Polish population. Fourteen polymorphisms in WNT3, WNT3A, WNT5A, WNT8A, WNT9B, and WNT11 were tested in a group of 210 patients with NCL/P and in a properly matched control group. The most significant results were found for the WNT3 rs3809857 variant, which, under the assumption of a recessive model, was associated with a two-fold decrease in the risk of NCL/P (OR(TT vs. GT + GG) = 0.492, 95% CI: 0.276-0.879, P = 0.015). Moreover, haplotype analysis revealed that WNT3 is significantly correlated with NCL/P. The global P-values for haplotypes of rs12452064_rs7207916 and rs3809857_rs12452064_rs7207916 were 0.0034 and 0.0014, respectively, and these results were statistically significant, even after the permutation test correction. In conclusion, our study confirmed the involvement of polymorphisms in the WNT3 gene in NCL/P aetiology in the tested population.

BACKGROUND Accumulating evidence suggests that elevated plasma homocysteine (Hcy), prevalent in hypertensive patients, affects oxidant/antioxidant balance of the body, and is linked to the development of atherosclerosis, inflammation, and endothelium injury. Our objective was to examine a hypothesis that Hcy is a predictor of total antioxidant status (TAS) and endothelial progenitor cells (EPCs), important in the repair of injured endothelium, in hypertensive patients. METHODS This study was conducted with newly diagnosed essential hypertension patients (n=42) and healthy controls (n=20). Anthropometric and biochemical characteristics, including plasma Hcy, lipids, TAS, and C-reactive protein (CRP) were quantified. Intima-media thickness (IMT) was assessed in carotid arteries. Blood derived EPCs were quantified using an in vitro culture assay. RESULTS Hcy, IMT, and CRP were significantly elevated while TAS and EPCs were significantly lower in hypertensive patients compared with controls. In multivariate regression analysis Hcy was a predictor of IMT of carotid artery and EPCs number. CONCLUSIONS Our results suggest that Hcy might increase carotid artery IMT by reducing EPCs numbers. Possible involvement of Hcy in the reduction of EPCs number in hypertensive patients might be in part mediated by Hcy influence on the TAS.

To study the mechanism by which sulfated polysaccharides with 1,3-β- d -glucan as a main chain exert anti-HIV-1 activity, we analyzed the effects of curdlan sulfate (CRDS) on HIV-1 infection of SupT-1 cells and peripheral blood mononuclear cells. CRDS had no effect on virions, inhibited weakly HIV-1 attachment to cells, and had to be present for 24 hr to achieve protection. Lack of HIV-1 DNA corresponding to the gag region in cells incubated with the virus and CRDS and inhibition of infection after addition of 2′,3′-dideoxyinosine to cells treated with CRDS and HIV-1 for less than 24 hr suggest that CRDS delays events that precede and/or include reverse transcription. Analysis of the effect of CRDS on binding of HIV-1 neutralizing antibodies to gp120 demonstrated that both the continuous epitopes on the V3 loop and the discontinuous CD4 binding site of gp120 represent targets for CDRS. This interaction of CRDS with functional gp120 domains suggests that CRDS interferes with the membrane fusion process during HIV-1 infection. Concentrations of CRDS that were protective against infection with T cell- and macrophage-tropic HIV-1 isolates had less suppressive effects on T cell function in comparison with the related compound, dextran sulfate.

The aim of the study was to determine the extent of oxidative DNA damage (levels of 8-oxo2dG) and expression of OGG1 and p53 and TNF-α proteins in lymphocytes of Alzheimer's disease (AD) patients and a control group. The studies were conducted on 41 patients with AD, including 25 women and 16 men aged 34-84 years. The control group included 51 individuals, 20 women and 31 men aged 22-83 years. The level of 8-oxo2dG was determined using HPLC/EC/UV, and the level of OGG1 and p53 and TNF-α proteins was determined with the Western blot method. The results showed that both proteins participating in DNA repair (OGG1, p53) and the inflammatory protein TNF-α are involved in pathogenesis of neurodegenerative diseases. It also seems that a specific system for DNA repair (OGG1) may contribute to downregulation of the inflammatory factor (TNF-α) level, especially in the early stages of dementia. Moreover, the results showed that p53 protein can fulfil its function in DNA damage repair only in early stages of dementia. It is possible that OGG1 and p53 and TNF-α proteins together or separately may be involved in pathogenesis of AD by repair of oxidative DNA damage and/or apoptosis.

Nonsyndromic cleft lip with or without cleft palate (NCL/P) is one of the most common craniofacial malformations; however, its aetiology is still unclear. Because the effects of maternal nutrition on fetal development are well known, we decided to pursue the question of whether polymorphic variants of genes encoding enzymes involved in choline metabolism might be associated with the maternal risk of having a baby with NCL/P. Analysis of 18 single nucleotide polymorphisms (SNPs) of betaine-homocysteine methyltransferase (BHMT), betaine-homocysteine methyltransferase-2 (BHMT2), choline dehydrogenase (CHDH), choline kinase (CHKA), dimethylglycine dehydrogenase (DMGDH), choline-phosphate cytidylyltransferase A (PCYT1A), and phosphatidylethanolamine N-methyltransferase (PEMT) provided evidence that polymorphisms located in the region containing BHMT and BHMT2 were protective factors against NCL/P affected pregnancies in our population. The strongest signal was found for the SNP located in the intronic sequence of BHMT2. Women carrying two copies of the rs625879 T allele had a significantly decreased risk of having offspring with orofacial clefts. These results were significant, even after correction for multiple comparisons. Moreover, the gene-gene interaction analysis revealed a significant epistatic interaction of BHMT2 (rs673752), PEMT (rs12325817), and PCYT1A (rs712012) with maternal NCL/P susceptibility. Altogether, our study identified a novel gene, the nucleotide variants of which were be associated with a decreased risk of having a baby with NCL/P.

In the last decade the abnormalities in male infertility became the main problem of more than 50% couples. The main reasons of male infertility are abnormal gonadotropin releasing hormone (GnRH) secretion, pituitary gland diseases and presence of testicular genetic defects. The male infertility also may result from chemotherapy, radiotherapy and viral infections. The main genetic factors responsible for male infertility encompass the mutations of genes, which encode important factors of spermatogenesis. Recently mRNAs of numerous genes have been identified in spermatozoa. The first transcripts found in spermatozoa included protamine 1 and 2 (PRM1 and PRM2). Protamines are basic polypeptides, which form complex with DNA in spermatids and spermatozoa. Structure of PRM1 and PRM2 genes and function of these proteins suggest the possible relationship between of protamines expression disorders and male infertility. The PRM1, PRM2 and transition proteins 1 and 2 (TP1 and TP2) play important role in DNA condensation. We attempted to present current knowledge regarding structure and expression regulation of PRM1 and PRM2 genes. We also discussed the effect of disorders of PRM1 and PRM2 expression on male infertility.

This paper describes an ongoing investigation into the potential impact that the Semantic Web could have on the personal privacy of individuals. The argument presented is that personal privacy should become part of the underlying architecture and design of the Semantic Web in order to limit the vulnerability of individuals. The current structure of the Semantic Web does not explicitly address the issue of the control of personal data, which could in turn lead to individuals being placed in positions of vulnerability. Personal privacy is seen as a major element of vulnerability and has caused some dilemmas from the legal perspective, balancing those who would hide their wrongdoing behind privacy against those who would be exposed to harm if there were no privacy. Issues of privacy are explored from the perspective of three groups of individuals: survivors of domestic violence; people who are not IT specialists; and teenagers. The impact of current web technologies on these groups is explored in order to gain insight into how the Semantic Web might be adapted. The paper concludes with a proposal for further research into the development of a Semantic Web tool which will aim to support individuals in identifying the potential threats to their privacy that arise from each sortie into cyberspace. Particular emphasis will be given to the issues faced by vulnerable groups and individuals.

The aetiology of non-syndromic cleft lip with or without cleft palate (CL/P) is very complex. It has been shown that polymorphic variants of genes encoding key proteins of folate and methionine metabolism might be important maternal risk factors of having a child with this craniofacial anomaly. Therefore, in our study, mothers with CL/P children as well as control mothers were examined for prevalence of polymorphisms of genes that encode methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), 5,10-methylenetetrahydrofolate dehydrogenase, 5,10-methenyltetrahydrofolate cyclohydrolase and 10-formyltetrahydrofolate synthetase (MTHFD1) and reduced folate carrier 1 (RFC1). We observed that there were no statistical differences in allele and genotype frequencies of MTHFR c.677CT, MTHFD1 c.1958GA and RFC1 c.80GA between mothers who had children with CL/P and control mothers. However, mothers with MTR c.2756AG or GG genotype displayed a 2.195-fold increased risk of having a child with CL/P (95% CI 1.189-4.050, p = 0.011). The mechanism by which polymorphic transition of MTR gene might increase the maternal risk of having CL/P progeny is unknown. Our observations are consistent with a significant role of the methyl cycle in the development of craniofacial structures in humans.

Discoid (DLE), discoid disseminated (DDLE) and subacute cutaneous lupus erythematosus (SCLE) are recognised as cutaneous forms of lupus erythematosus (LE). It has been suggested that expression of endogenous retroviral components might induce the biosynthesis of antiDNA antibodies in LE patients. Using the dot blot hybridisation, we detected the greatest correlation between biosynthesis of anti-double stranded DNA (anti-dsDNA), anti-single stranded DNA (anti-ssDNA) antibodies and the presence of human immunodeficiency virus type I (HIV-1) pol sequences in DNA isolated from serum of SCLE (n = 22) patients. The same studies conducted in the groups of DLE (n = 85) and DDLE (n = 51) patients, exhibited a lower correlation between production of anti-dsDNA, anti-ssDNA and the presence of homologous HIV-1 pol sequences than in SCLE patients. Our findings suggest that the presence of endogenous retroviral sequences in patient serum may exhibit a relationship with development of cutaneous forms of LE disease.

The HIV-1 X4-isolates replicate more efficiently in Th2 than in Th1 cells, isolated from peripheral blood lymphocytes of HIV-1 seronegative individuals. The semiquantitative RT-PCR revealed higher level of transcripts of the HIV-1 co-receptor CXCR4 in Th2 cells than in Th1 cells which might explain better replication of HIV-1 X4-isolates in these cells. Lower expression of CXCR4 in Th1 cells render these cells less susceptible to infection with HIV-1.

It has been known that lipopolysaccharides (LPS) as well as superantigens increase activity of transcription factor NF-kappaB in monocyte-derived macrophages and monocytic cell lines. To examine the mitogenic effect of high molecular weight dextran sulphate (HMDS), the monocytic cell line THP-1 was transfected with a plasmid vector containing chloramphenicol acetyl transferase (CAT) reporter gene linked to the HIV-1 long terminal repeat (LTR) promoter, that is regulated by the transcription factor NF-kappaB. We have demonstrated that HMDS, similar to bacterial LPS, increases the expression of CAT reporter gene, indicating increased activity of NF-kappaB.

The research described in this paper was carried out at GEC-Plessey Semiconductors (GPS) in Plymouth, England, and describes a study of industry practice and problems associated with the management of engineering design teams within the company. GPS designs and fabricates complex, silicon, integrated circuits—for example, embedded microprocessors for cellnet telephones—and competes successfully in this volatile global market. GPS is a ‘fast cycle time’ company (Meyer, 1993), applying total quality management principles in the use of self-managing work teams, continuous process improvement, and participative management (Jablonski, 1991). Its workforce is therefore accustomed to working in an environment of rapid change.

High-molecular-weight dextran sulfate (HMDS) inhibits infection of CD4+ lymphocytes by T-cell (T)-tropic human immunodeficiency virus (HIV) isolates, but augments replication of macrophage (M)-tropic isolates in primary human macrophages and phorbol myristate acetate (PMA)-differentiated THP-1 monocytic cells. To address the mechanism responsible for HMDS-mediated increases in HIV replication in macrophages, we analyzed the interaction between HMDS and functional domains of gp120 on the surface of PMA-differentiated THP-1 cells infected with M-tropic HIV isolates. Immunofluorescence staining of the infected cells revealed that HMDS inhibited the binding of monoclonal antibodies (mAbs) directed to the V3 and C4 domains of gp120, but augmented the binding of three neutralizing antibodies directed to the V2 region of gp120. The extent of HMDS-mediated changes within the V2 loop of gp120 was associated with increased virus binding and replication in PMA-differentiated THP-1 cells and primary macrophages. The effect was dependent on expression of the CCR5 receptor and was inhibited by the beta-chemokine RANTES. Results of this study suggest that HMDS-mediated increases in HIV infection in macrophages are associated with conformational changes within the V2 region of gp120 and enhanced interaction between gp120 and the CCR5 coreceptor on the target cell.

The effect of heparin sulphate on the infection of CD4+ lymphocytes by recombinant HIV-1 clones pIIIB and by pIIIB/V3-BaL was investigated. It was demonstrated that heparin sulphate decreased the infectivity of CD4+ lymphocytes by the pIIIB virus stronger than by the pIIIB/V3-BaL clone, and that the effect of heparin was concentration-dependent. This was accompanied by an inhibition of binding of the monoclonal antibodies 447-52-D to the V3 region and G45-60 to the C4 region of oligomeric glycoprotein 120 (gp120). It has been concluded that the inhibitory effect of heparin sulphate on the infection of CD4+ lymphocytes by recombinant HIV-1 clones is mediated mainly by the V3 region of gp120. However, the C4 region contributes to the inhibitory effect of heparin sulphate.

This paper starts by describing the findings of three linked studies of the early stages of the process of electronics design. These studies identify a set of interrelated problems which have been found to exist widely in the industry. The problems lie in the areas of specification, risk management, designers’ roles, project planning and organisational knowledge. These problems are compounded by the complex dynamics of project team working which are only rarely amenable to static management and control tactics. Interrelationships between these problems are identified and an integrated approach to their solution is outlined, consisting of a socio-technical system based on the notion of dynamic contingency management, supported by interacting software agents. The paper concludes with short descriptions of the requirements for some of the key components and their roles in the system.

A sulfated polysaccharide, curdlan sulfate (CRDS) with 1,3-β- D -glucan as a main chain, inhibits HIV-1 infection of human peripheral blood lymphocytes (PBLs) by binding to the V3 region of gp120. We previously showed that T cell (T)-tropic HIV-1 isolates are over 10-fold more sensitive to neutralization by CRDS than macrophage (MT)-tropic viruses, which posseses a relatively less charged amino acid composition in the V3 sequence. To analyze the interaction of CRDS with V3 and its association with neutralization sensitivity of HIV-1 isolates, we examined the effect of CRDS on the binding of neutralizing antibodies to monomeric and oligomeric gp120 mutants of T- and MT-tropic HIV-1 clones in which the V3 loop was either deleted or substituted by V3 of another isolate. Our results showed that the presence and the amino acid composition of the V3 loop appears to determine the extent of interaction of CRDS with the V2 and CD4-binding regions on native gp120 monomers; however, the positive charge of V3 has less effect on this interaction on oligomeric gp120. Furthermore, our results established that only the CRDS-induced masking of V3 on oligomeric gp120 appears to be associated with the anti-HIV-1 activity of CRDS in vitro. Our findings underline the usefulnes of CRDS for understanding the structural constraints on gp120 that drive the transition from MT- to T-tropic isolates in vivo and enable the virus to use multiple fusion cofactors.