The child's first dental visit. Age, reasons, oral health status and dental treatment needs among children in Southern Poland.

AIM: The aim of this study was to determine the age at and the reasons for the child's first dental visit, and to assess the oral health status and treatment needs in the analysed group of paediatric patients. MATERIALS AND METHODS: The study involved 320 children (154 girls and 166 boys) aged between 0.7 months and 13.5 years, visiting the dentist for the first time. All parents/legal guardians of the study participants gave written informed consent for participation in the study. Data on the child's age and reason for the dental visit were collected from interviews with parents. The state of oral health and dental treatment needs were assessed based on clinical examination, according to recommendations of the World Health Organization. STATISTICAL ANALYSIS: collected data were entered into an Excel spreadsheet and analysed using IBM SPSS software (version 24). Research hypotheses were verified using the Chi-square independence test at the level of statistical significance p<0.05. RESULTS: The mean age of children at their first dental visit was 3.79 years (+/- 1.82 years). The most common reasons (60%) for the first dental visit were pain followed by dental caries (33.1%) and the presence of decayed teeth (26.9%). The frequency of caries in the population was 75.9%, which means that only one out of four examined children was free from dental caries. Only 23.1% of patients did not require dental treatment and as many as 76.9% of the studied population needed dental treatment. CONCLUSION: Polish children make their first dental visit too late (usually at the age of 4 years) in relation to medical recommendations (between 6 and 12 months of life). The predominant reason for the child's first dental visit is caries and its complications. The results of this study indicate the bad oral health of Polish children making their first dental visit and low health awareness of parents and guardians.

Holomycin and an antibiotic (MM 19290) related to tunicamycin, metabolites of Streptomyces clavuligerus.

Streptomyces clavuligerus produces penicillin N, several cephalosporins and the beta-lactamase inhibitor clavulanic acid. The detection, isolation and properties of further metabolites of this culture, MM 21801 and MM 19290, are described. MM 21801 was identified as the antibiotic holomycin. MM 19290 was shown to be related to tunicamycin, an antibiotic complex obtained from cultures of Streptomyces lysosuperificus.

MM 46115, a new antiviral antibiotic from Actinomadura pelletieri. Characteristics of the producing cultures, fermentation, isolation, physico-chemical and biological properties.

Six strains of Actinomadura pelletieri were shown to produce a novel macrolide antibiotic, designated MM 46115. MM 46115 was active against parainfluenza virus 1 and 2 and Gram-positive bacteria. Methods are described for the production of MM 46115 by strain IP 729.63, and for the isolation of the compound from a butanol extract of the culture filtrate.

Antimicrobial activities and antagonists of bacilysin and anticapsin.

The dipeptide antibiotic bacilysin is active against a wide range of bacteria and against Candida albicans. Its C-terminal amino acid, anticapsin, is a very poor antibacterial agent. The activities of both substances are strongly dependent on the nature of the culture medium. In a minimal medium the minimum inhibitory concentration for bacilysin with E. coli B is 10(-3) mug ml(-1). The action of bacilysin amino acids. With several bacteria, bacilysin-resistant mutants are found in unusually large numbers. It is suggested that peptide and amino acid transport systems play a role in these phenomena. The antimicrobial action of bacilysin is also inhibited by glucosamine and N-acetylglucosamine. This antibiotic may therefore interfere with glucosamine synthesis and thus with the synthesis of microbial cell walls.

The mode of action of bacilysin and anticapsin and biochemical properties of bacilysin-resistant mutants.

Bacilysin is hydrolysed to L-alanine and anticapsin by suspensions of a bacilysin-sensitive strain of Staphylococcus aureus but not by those of a resistant strain derived from it. In contrast, it is hydrolysed by extracts of both strains. Anticapsin is a powerful inhibitor of glucosamine synthetase in extracts of both the bacilysin-sensitive and -resistant strains of Staph. aureus. Bacilysin, by comparison, is a relatively poor inhibitor of glucosamine synthetase in crude extracts when its hydrolysis is inhibited by EDTA. A phenylalanine auxotroph of Staph. aureus readily uses L-analyl-L-phenylalanine for growth, but a bacilysin-resistant mutant of this strain does not. It is suggested that the antibacterial activity of bacilysin depends on its transport into the organism, its hydrolysis to anticapsin and on inhibition by the latter of glucosamine synthetase, and that bacilysin-resistant mutants are defective in a transport system.

Metabolism of penicillins to penicilloic acids and 6-aminopenicillanic acid in man and its significance in assessing penicillin absorption.

Penicillins can be metabolized to penicilloic acids in man, the extent being dependent on the penicillin structure. In the phenoxy penicillin series, phenoxymethyl penicillin was found to be particularly unstable, but the higher homologues were more stable. In the isoxazolyl series, oxacillin was unstable, and progressive insertion of halogen in the phenyl ring increased stability. Ampicillin and amoxycillin showed some instability, ampicillin possibly being the more stable. After intramuscular administration, carbenicillin was very stable in the body, ampicillin was fairly stable, and benzyl penicillin was unstable. It is important to take into account the penicilloic acid content of urine when estimating total absorption of a penicillin. Increased stability in the body as well as slower renal clearance can lead to high concentrations in the serum. Penicilloic acids seemed to be more slowly cleared from the body than penicillins. The liver is probably the site of inactivation.

Major differences in stability and dimerization properties of two chimeric mutants of human stefins.

Stefins A and B are cysteine proteinase inhibitors that have considerable sequence similarity but marked differences in their stability and folding properties. Two chimeric proteins were designed to shed light on these differences. The chimeric mutants have been expressed in Escherichia coli and have been isolated. The first, A37B, consists of 37 residues of stefin A, comprising the N-terminal and the alpha-helix, joined to 61 residues of stefin B; the second, A61B, consists of 61 N-terminal residues of stefin A, followed by 37 residues of stefin B. Spectroscopic properties of the chimeric proteins (absorption, CD, and NMR spectra), together with activity measurements, have confirmed that both have well-defined tertiary structure and are active as cysteine proteinase inhibitors. Characterization consisted of GuHCl denaturation, ANS binding as a function of pH, and monitoring of dimerization under partially denaturing conditions. The c(m) values are 1.3 M GuHCl for A61B as compared with 2.7 M GuHCl for stefin A, and 2.1 M GuHCl for A37B as compared with 1.4 M GuHCl for stefin B (all at pH 7.5, 25 degrees C). However (G degrees (N-U) is lower for both chimeric proteins (18 +/- 3 kJ/mol) than for the parent stefins (28 +/- 3 kJ/mol). In pH denaturation, unlike stefin B, neither chimeric mutant unfolds to I(N) below pH 5.4. At pH 3, where stefin B forms a molten globule and stefin A is native, both A37B and A61B show increased ANS fluorescence and aggregate visibly. Dimers at pre-denaturation conditions are observed in all the proteins under study, but they remain "trapped" only in stefin A.