Chromatin structure and DNase I hypersensitivity in the transcriptionally active and inactive porcine tumor necrosis factor gene locus

We have analyzed the chromatin structure of the porcine tumor necrosis factor gene locus (TNF-alpha and TNF-beta). Nuclei from porcine peripheral blood mononuclear cells were digested with different nucleases. As assessed with micrococcal nuclease, the two TNF genes displayed slightly faster digestion kinetics than bulk DNA. Studies with DNaseI revealed distinct DNaseI hypersensitive sites (DH-sites) within the porcine TNF locus. Four DH-sites could be observed in the promoter and mRNA leader regions of the TNF-beta gene. Two DH-sites could be observed for the TNF-alpha gene, one located in the promoter region close to the TATA-box and the other site in intron 3. This pattern of DH-sites was present independently of the activation state of the cells. Interestingly in a porcine macrophage-like cell line, we found that the TNF-alpha promoter DH-site disappeared and another DH-site appeared in the region of intron 1. Additionally, the DH-site of intron 3 could be enhanced by PMA-stimulation in these cells. TNF-beta sites were not detected in this cell line. However, DH-sites were totally absent in fibroblasts (freshly isolated from testicles) and in porcine kidney cells (PK15 cell line) both of which do not transcribe the TNF genes. Therefore, the pattern of DH-sites corresponds to the transcriptional activity of analyzed cells.

The U7 snRNP and the hairpin binding protein: Key players in histone mRNA metabolism.

Animal replication-dependent histone mRNAs are subject to several post-transcriptional regulatory processes. Their non-polyadenylated 3' ends are formed preferentially during S phase by a unique nuclear cleavage event. This requires the base pairing between U7 snRNA and a histone spacer element 3' of the cleavage site. Cleavage occurs preferentially after adenosine, at a fixed distance from the hybrid region. A conserved RNA hairpin just upstream of the cleavage site is recognised by the hairpin binding protein (HBP) that acts as an auxiliary processing factor, stabilising the interaction of the histone pre-mRNA with the U7 snRNP. The interaction between HBP and the RNA hairpin is very stable and HBP is also found associated with histone mRNAs on polysomes. The hairpin and presumably, HBP are also required for nuclear export and translation of histone mRNA. Furthermore, histone mRNAs are selectively destabilised in the G2 phase or upon inhibition of DNA synthesis and this regulation is also associated with the hairpin. Recently, HBP-encoding cDNAs were isolated from various organisms. Human, mouse and Xenopus laevis HBPs are similar, while the Caenorhabditis elegans protein has significant homology to the others only in a central RNA binding domain.Copyright 1997 Academic Press Limited

Parallel synthesis and nucleic acid binding properties of C(6')-[alpha]-functionalized bicyclo-DNA

Two novel bicyclo-T nucleosides carrying a hydroxyl or a carboxymethyl substituent in C(6')-[alpha]-position were prepared and incorporated into oligodeoxynucleotides. During oligonucleotide deprotection the carboxymethyl substituent was converted into different amide substituents in a parallel way. Tm-measurements showed no dramatic differences in both, thermal affinity and mismatch discrimination, compared to unmodified oligonucleotides. The post-synthetic modification of the carboxymethyl substituent allows in principle for a parallel preparation of a library of oligonucleotides carrying diverse substituents at C(6'). In addition, functional groups can be placed into unique positions in a DNA double helix.

Serum concentrations of lectin-pathway components in healthy neonates, children and adults: mannan-binding lectin (MBL), M-, L-, and H-ficolin, and MBL-associated serine protease-2 (MASP-2)

This study aimed to measure serum concentrations of five lectin-pathway components, mannan-binding lectin (MBL), M-ficolin, L-ficolin, H-ficolin, and MBL-associated serine protease-2 (MASP-2), in healthy neonates and children, to determine if they change with age and to compare them with serum concentrations in healthy adults. Concentrations were measured in 141 preterm and 30 term neonates, in 120 children including infants and adolescents, and in 350 adults (97 for L-ficolin) by inhouse time-resolved immunofluorometric assays or commercially available enzyme-linked immunosorbent assays. The adjacent categories method applying Wilcoxon-Mann-Whitney tests was used to determine age categories where concentrations differed significantly. Displaying serum concentration vs. age, an inverted-U shape (higher concentrations in children than in neonates and adults) was found for MBL and the ficolins, and an S-shape for MASP-2. Serum concentrations of all five lectin-pathway components were significantly lower in preterm neonates <32-wk gestational age compared to older neonates, infants, and children. Only M-ficolin in children >1 yr and H-ficolin in term neonates and in children were found to be comparable with adult values. MBL, M-, L-, and H-ficolin, and MASP-2 serum concentrations show important changes with age. The respective normal ranges for adults should not be used in the pediatric population. The age-specific pediatric ranges established here may be used instead.

Evaluation of chemically modified SLA implants (modSLA) biofunctionalized with integrin (RGD)- and heparin (KRSR)-binding peptides

Enhancing osseointegration through surface immobilization of multiple short peptide sequences that mimic extracellular matrix (ECM) proteins, such as arginine-glycine-aspartic acid (RGD) and lysine-arginine-serine-arginine (KRSR), has not yet been extensively explored. Additionally, the effect of biofunctionalizing chemically modified sandblasted and acid-etched surfaces (modSLA) is unknown. The present study evaluated modSLA implant surfaces modified with RGD and KRSR for potentially enhanced effects on bone apposition and interfacial shear strength during early stages of bone regeneration. Two sets of experimental implants were placed in the maxillae of eight miniature pigs, known for their rapid wound healing kinetics: bone chamber implants creating two circular bone defects for histomorphometric analysis on one side and standard thread configuration implants for removal torque testing on the other side. Three different biofunctionalized modSLA surfaces using poly-L-lysine-graft-poly(ethylene glycol) (PLL-g-PEG) as a carrier minimizing nonspecific protein adsorption [(i) 20 pmol cm⁻² KRSR alone (KRSR); or in combination with RGD in two different concentrations; (ii) 0.05 pmol cm⁻² RGD (KRSR/RGD-1); (iii) 1.26 pmol cm⁻² RGD (KRSR/RGD-2)] were compared with (iv) control modSLA. Animals were sacrificed at 2 weeks. Removal torque values (701.48-780.28 N mm), bone-to-implant contact (BIC) (35.22%-41.49%), and new bone fill (28.58%-30.62%) demonstrated no significant differences among treatments. It may be concluded that biofunctionalizing modSLA surfaces with KRSR and RGD derivatives of PLL-g-PEG polymer does not increase BIC, bone fill, or interfacial shear strength.

[Active and healthy living in old age--results from a representative survey of community-dwelling senior citizens in Hamburg]

BACKGROUND: The majority of community-dwelling people 60 years and older are independent and live actively. However, there is little information about elderly persons' views on aging, health and health promotion. METHODS: Therefore, an anonymous, written questionnaire survey was performed in a representative sample of inhabitants from a section of the city of Hamburg, 60 years and older; 5 year intervals, 14 subsamples according to 7 age groups of females and males. RESULTS: Questionnaires from 950 participants (29% response) could be evaluated: mean age 71.5 years, 58% women, 34% living alone, 5% with professional healthcare needs as indicated by status according to German nursing care insurance. Senior citizens' positive attitudes towards aging and health were predominant: 69% of respondents felt young, 85% worried about loss of autonomy in old age. CONCLUSIONS: The results provide evidence indicating potential for improving health-promoting lifestyles in parts of the older population by evaluating and strengthening older persons' competencies and by considering their concerns seriously. These results provide valuable information for future plans in the public-health sector in the city of Hamburg where particular health-promoting actions for elderly persons will be considered.

Differentiation between active and chronic Crohn's disease using MRI small-bowel motility examinations — Initial experience

AIM: To evaluate the influence of locally active Crohn's disease on systemic small-bowel motility in patients with chronic Crohn's disease compared to healthy individuals. MATERIAL AND METHODS: Fifteen healthy individuals (11 men, four women; mean age 37 years) and 20 patients with histopathologically proven active (n = 15; 10 women, 5 men; mean age 45 years) or chronic (n = 5; four women, one man; mean age 48 years) Crohn's disease were included in this institutional review board-approved, retrospective study. Magnetic resonance imaging (MRI; 1.5 T) was performed after standardized preparation. Two-dimensional (2D) cine sequences for motility acquisition were performed in apnoea (27 s). Motility assessment was performed using dedicated software in three randomly chosen areas of the small-bowel outside known Crohn's disease-affected hotspots. The main quantitative characteristics (frequency, amplitude, occlusion rate) were compared using Student's t-test and one-way analysis of variance (ANOVA). RESULTS: Three randomly chosen segments were analysed in each participant. Patients with active Crohn's disease had significantly (p < 0.05) reduced contraction frequencies (active Crohn's disease: 2.86/min; chronic: 4.14/min; healthy: 4.53/min) and luminal occlusion rates (active: 0.43; chronic: 0.70; healthy: 0.73) compared to healthy individuals and patients with chronic Crohn's disease. Contraction amplitudes were significantly reduced during active Crohn's disease (6.71 mm) compared to healthy participants (10.14 mm), but this only reached borderline significance in comparison to chronic Crohn's disease (8.87 mm). Mean bowel lumen diameter was significantly (p = 0.04) higher in patients with active Crohn's disease (16.91 mm) compared to healthy participants (14.79 mm) but not in comparison to patients with chronic Crohn's disease (13.68). CONCLUSION: The findings of the present study suggest that local inflammatory activity of small-bowel segments in patients with active Crohn's disease alters small-bowel motility in distant, non-affected segments. The motility patterns revealed reduced contraction-wave frequencies, amplitudes, and decreased luminal occlusion rates. Thus evaluation of these characteristics potentially helps to differentiate between chronic and active Crohn's disease.

Risk factors associated with the longevity of multi-rooted teeth. Long-term outcomes after active and supportive periodontal therapy

AIM To investigate risk factors for the loss of multi-rooted teeth (MRT) in subjects treated for periodontitis and enrolled in supportive periodontal therapy (SPT). MATERIAL AND METHODS A total of 172 subjects were examined before (T0) and after active periodontal therapy (APT)(T1) and following a mean of 11.5 ± 5.2 (SD) years of SPT (T2). The association of risk factors with loss of MRT was analysed with multilevel logistic regression. The tooth was the unit of analysis. RESULTS Furcation involvement (FI) = 1 before APT was not a risk factor for tooth loss compared with FI = 0 (p = 0.37). Between T0 and T2, MRT with FI = 2 (OR: 2.92, 95% CI: 1.68, 5.06, p = 0.0001) and FI = 3 (OR: 6.85, 95% CI: 3.40, 13.83, p < 0.0001) were at a significantly higher risk to be lost compared with those with FI = 0. During SPT, smokers lost significantly more MRT compared with non-smokers (OR: 2.37, 95% CI: 1.05, 5.35, p = 0.04). Non-smoking and compliant subjects with FI = 0/1 at T1 lost significantly less MRT during SPT compared with non-compliant smokers with FI = 2 (OR: 10.11, 95% CI: 2.91, 35.11, p < 0.0001) and FI = 3 (OR: 17.18, 95% CI: 4.98, 59.28, p < 0.0001) respectively. CONCLUSIONS FI = 1 was not a risk factor for tooth loss compared with FI = 0. FI = 2/3, smoking and lack of compliance with regular SPT represented risk factors for the loss of MRT in subjects treated for periodontitis.

Specificities of Caenorhabditis elegans and human hairpin binding proteins for the first nucleotide in the histone mRNA hairpin loop.

The 3' ends of animal replication-dependent histone mRNAs are formed by endonucleolytic cleavage of the primary transcripts downstream of a highly conserved RNA hairpin. The hairpin-binding protein (HBP) binds to this RNA element and is involved in histone RNA 3' processing. A minimal RNA-binding domain (RBD) of approximately 73 amino acids that has no similarity with other known RNA-binding motifs was identified in human HBP [Wang Z-F et al., Genes & Dev, 1996, 10:3028-3040]. The primary sequence identity between human and Caenorhabditis elegans RBDs is 55% compared to 38% for the full-length proteins. We analyzed whether differences between C. elegans and human HBP and hairpins are reflected in the specificity of RNA binding. The C. elegans HBP and its RBD recognize only their cognate RNA hairpins, whereas the human HBP or RBD can bind both the mammalian and the C. elegans hairpins. This selectivity of C. elegans HBP is mostly mediated by the first nucleotide in the loop, which is C in C. elegans and U in all other metazoans. By converting amino acids in the human RBD to the corresponding C. elegans residues at places where the latter deviates from the consensus, we could identify two amino acid segments that contribute to selectivity for the first nucleotide of the hairpin loop.

The independent role of prenatal and postnatal exposure to active and passive smoking on the development of early wheeze in children.

Maternal smoking during pregnancy increases childhood asthma risk, but health effects in children of nonsmoking mothers passively exposed to tobacco smoke during pregnancy are unclear. We examined the association of maternal passive smoking during pregnancy and wheeze in children aged ≤2 years.Individual data of 27 993 mother-child pairs from 15 European birth cohorts were combined in pooled analyses taking into consideration potential confounders.Children with maternal exposure to passive smoking during pregnancy and no other smoking exposure were more likely to develop wheeze up to the age of 2 years (OR 1.11, 95% CI 1.03-1.20) compared with unexposed children. Risk of wheeze was further increased by children's postnatal passive smoke exposure in addition to their mothers' passive exposure during pregnancy (OR 1.29, 95% CI 1.19-1.40) and highest in children with both sources of passive exposure and mothers who smoked actively during pregnancy (OR 1.73, 95% CI 1.59-1.88). Risk of wheeze associated with tobacco smoke exposure was higher in children with an allergic versus nonallergic family history.Maternal passive smoking exposure during pregnancy is an independent risk factor for wheeze in children up to the age of 2 years. Pregnant females should avoid active and passive exposure to tobacco smoke for the benefit of their children's health.