The sodium ion translocating oxaloacetate decarboxylase of Klebsiella pneumoniae. Sequence of the integral membrane-bound subunits beta and gamma

The sequences upstream and downstream of the cloned gene for the alpha-subunit of the Na+ pump oxaloacetate decarboxylase of Klebsiella pneumonia were determined. An open reading frame in the upstream region was identified as the gene for the gamma-subunit, and an open reading frame in the downstream region represents the gene for the beta-subunit. The deduced primary structure of the gamma- and beta-subunit was confirmed by protein sequencing of about 37 and 22%, respectively, of each polypeptide chain. The gene for the gamma-subunit has a GC content of 64% and codes for 83 amino acids. The protein is not processed at its amino terminus or at its carboxyl terminus. The gene for the beta-subunit has a GC content of 66% and codes for 327 amino acids. The protein contains a blocked aminoterminal methionine residue. Whether processing occurs at the carboxyl terminus is unknown. Hydropathy calculations defined one transmembrane helix in the amino-terminal part of the gamma-subunit and a hydrophilic carboxyl-terminal part that is certainly not embedded within the lipid bilayer. A proline- and alanine-rich sequence in the carboxyl-terminal part may provide the protein with conformational flexibility. According to hydropathy and acrophilicity calculations, the secondary structure of the beta-subunit may be formed with 5 or 6 intramembrane helical segments.

Dental caries, visible plaque, and gingival bleeding in young adult Danes in alternative dental programs

From 16 to 19 years of age three groups of young adults received alternative dental programs on termination of the Public Child Dental Health Service (PCDHS) in different municipalities: public group, n = 386; mixed group, n = 161; and private group, n = 261. Dental caries status at the start of the study was assessed from the standard PCDHS records, and caries, plaque, and gingivitis were examined in an epidemiologic survey at the end. Caries experience at 16 years was 11.6 DMFS, highest in the mixed group and increased in all groups during the study. Initial placement in caries severity zones did not change. Visible plaque index (VPI) and gingival bleeding index (GBI) showed that plaque and gingival bleeding were present in most subjects, but rather few surfaces were affected. Association between gingival bleeding and non-use of dental services was found. Overall, it is concluded that none of the alternative programs differed from each other in having measurable effects on the oral health status.

Dental treatment provided to young adult Danes enrolled in alternative dental programs during a 3-year period

From age 16 to 19 years three groups of young adults received alternative dental programs on termination of the Public Child Dental Health Service (PCDHS) in different municipalities: public group, n = 386; mixed group, n = 161; and private group, n = 261. During the entire study information on dental service use by the participants was taken from the records and National Health Insurance files. All dental services were calculated relative to a standardized Dental Service Unit defined by the value of a dental examination. During the entire study a mean of 30.53 Dental Service Units were provided, corresponding to 10.18 per year. More than half were of a diagnostic preventive character, and well over one-fourth were fillings. Irrespective of dental program, differences in dental services were noted with regard to utilization of dental services and to initial caries status. Users with high caries experience also received more fillings, but fewer preventive services. No association was found between gingival status and dental services provided.

Genome structure of adenovirus 12 host range mutants adapted to growth in simian Vero cells

Mutants of adenovirus type 12 adapted to growth in Vero cells were studied by restriction enzyme and sequence analysis. Plaque-purified mutants were isolated either after long-term passage of the virus in Vero cells (CS-1, CL-1) or from Vero cells transfected with viral DNA (11-g, 12-k). The plaque-forming activity of these mutants was equal or even slightly higher in Vero cells than in HeLa cells, whereas the activity of wild-type virus in HeLa cells exceeded that in Vero cells by about one to two orders of magnitude. All mutants tested had an insertion of variable length consisting of adenoviral sequences at the right end of the viral genome. Sizes of the insertions were determined to be 294 bp (CS-1, 12-k), 560 (11-g), or 180 bp (CL-1). Additional insertions of multiple size and less than equimolar amount were detected and seem to exist in some of the viral particles. Furthermore, all four mutants tested showed an identical 69-bp deletion in the first exon of the E1a gene.

Shifts between use and non-use of dental services among young Danish adults over a 3-year period

Utilization of dental services among three groups of young adults was studied longitudinally. Each year from age 16 to age 19, participants were defined as users or non-users of alternative dental programs. Dental programs were taking place with public dental health service clinics (n = 386), with private dental practitioners, free of charge (n = 161), and with private dental practitioners, partially reimbursed by health insurance (n = 261). The paper analyzes whether the pattern of utilization of the last two groups might be described by a Markovian model defining use or non-use of dental care each of 3 years as two mutually exclusive Markovian states. Contingency table analysis of the relationships of the utilization status and sex, social group, and delivery program showed that the utilization pattern could not be described by a Markovian model. Conversely, strong relationships between 1-yr user status and 3-yr user status was found. Implications in relation to the prevailing dental health care policy emphasizing regular dental care and continuity between child dental health care and young adult dental programs are discussed.

Utilization of alternative delivery programs in youth dental care in Denmark

Three groups of young adults were offered three different dental programs from ages 16 to 19: one group of 386 persons continued preventive and curative dental care in the Public Child Dental Health Service (Public group), one group of 161 persons was offered dental care with private dental practitioners of own choice with care paid by the municipality and the health insurance (Mixed group), and one group of 261 persons entered the general young adult dental program under the National Health Insurance with free choice of private dental practitioner with reimbursement of about 75% from the insurance (Private group). Almost 100% of the Public group used the dental services continuously. Less than half of the Mixed group and about two thirds of the Private group went regularly to a dentist, women more than men. Discrepancies were found between the expected utilization and actual utilization, and a tendency was noted to overrate self-reported utilization in relation to actual utilization. It is concluded that continuity of dental care and unambiguous organizational affiliation is a prerequisite for a high utilization rate, but it also seems that the outreaching work done by the child dental health service is effective with regard to utilization.

Small angle X-ray scattering study on bovine porphobilinogen synthase (5-aminolaevulinate dehydratase)

The quaternary structure of the native (zinc) porphobilinogen synthase (5-amino-laevulinate dehydratase) from bovine liver and its lead-substituted derivative is studied in solution by small angle X-ray scattering. In spite of the profound inhibitory effect of lead ions in the enzyme they do not produce a change in the quaternary structure detectable by small angle X-ray scattering. The most important molecular parameters of the native enzyme were found to be: radius of gyration Rg = 4.04 +/- 0.04 nm and maximum dimension Dmax = 12.0 +/- 0.5 nm. The corresponding values for the lead derivative are: Rg = 4.26 +/- 0.1 nm and Dmax = 12.5 +/- 0.5 nm. The quaternary structure of the enzyme in solution is described by a model, which fits the experimental scattering and distance distribution function.

The sodium ion translocating oxalacetate decarboxylase of Klebsiella pneumoniae. Sequence of the biotin-containing alpha-subunit and relationship to other biotin-containing enzymes

The gene encoding the alpha-subunit of the Na+ pump oxalacetate decarboxylase of Klebsiella pneumoniae was cloned and sequenced. The deduced primary structure of the protein was confirmed by protein sequencing of about 30% of the polypeptide chain. The gene has a GC content of 67% and codes for 596 amino acids. The N-terminal methionine is removed in the mature protein which has a calculated molecular mass of 63,600 daltons. The protein consists of two different domains that are connected by a stretch of amino acid residues susceptible to proteolytic cleavage. Limited proteolysis of the native enzyme with trypsin produced fragments of about 51 kDa and 10.2 kDa, the latter of which started with valine 491 and contained the biotin prosthetic group. Peptide sequencing indicated binding of the biotin prosthetic group to lysine 561, 35 residues from the C terminus. The decarboxylase contains an extended alanine- and proline-rich region (positions 502-532) on the N-terminal side of the 10.2-kDa biotin domain. This sequence includes a total of 16 alanine and 9 proline residues.

Correlation of modified human papilloma virus early gene expression with altered growth properties in C4-1 cervical carcinoma cells

In cervical carcinomas and cell lines derived from these tumors the DNA of specific types of human papilloma viruses (HPVs) is integrated into the host cell genome. The two viral open reading frames E6 and E7 are consistently transcribed in tumors and cell lines, and the respective proteins were detected in cells cultured in vitro. As shown here, modulation of HPV 18 E6 and E7 gene expression in C4-1 cervical carcinoma cells is accompanied by an altered cell growth. HPV 18 E6 and E7 expression can be enhanced by glucocorticoid treatment of C4-1 cells, and an increased cell proliferation is observed. In contrast, after introduction of complementary RNA to the HPV 18 E6 and E7 open reading frames, their expression is inhibited, and decreased cell growth is observed. These results support the hypothesis that expression of HPV E6 and E7 open reading frames is directly involved in growth regulation of cervical carcinoma cells.

Identification of the human papillomavirus type 18 E6 and E6 proteins in nuclear protein fractions from human cervical carcinoma cells grown in the nude mouse or in vitro

We recently reported the transcription patterns of human papillomavirus (HPV) type 18 sequences in human cervical carcinoma cell lines. The open reading frames (ORFs) E6* and E6 represent the 5'-terminal cistrons in HPV18 mRNAs. ORF E6* was assumed to be specific for HPV types associated with genital carcinomas. To identify the predicted gene product, ORF E6* from a HeLa cDNA clone was expressed as an MS2 fusion protein in Escherichia coli. The C-terminal 23 amino acid residues were chemically synthesized. A panel of monoclonal antibodies was generated, recognizing E6* and E6* plus E6, respectively. In human cervical carcinoma cell lines grown in vitro these monoclonal antibodies specifically immunoprecipitate the putative Mr 17,000 and 18,000 HPV18 E6 proteins in nuclear protein fractions. In a HPV18 DNA containing human cervical carcinoma established in nude mice, these monoclonal antibodies specifically immunoprecipitate a polypeptide with a molecular weight of 6500 as predicted for the HPV18 ORF E6* gene product in a nuclear protein fraction.

Genetic interactions of modifier genes and modifiable alleles in Drosophila melanogaster

We have examined the effects of mutations in the six allele-specific modifier genes su(Hw), e(we), su(f), su(s), su(wa), and su(pr) on the expression of 18 modifiable alleles, situated at 11 loci. Ten of the modifiable alleles are associated with insertions of the gypsy retrotransposon and the others include alleles associated with insertions of copia and 412. We tested or retested 90 of the 108 possible combinations and examined the expression of modifiable alleles in flies mutant for pairs of modifier genes in various heterozygous and homozygous configurations. Our principal findings are: (1) a screen of 40,000 mutagenized X chromosomes yielded three new mutations in known modifier genes, but revealed no new modifier genes; (2) the modification effects of different mutations in a given modifier gene were qualitatively similar; (3) each of the six modifiers suppressed some modifiable alleles, enhanced others, and had no noticeable effect on still others; (4) the modifier genes could be placed in four classes, according to their effects on the gypsy-insertion alleles; and (5) the effects of mutations in different modifier genes combined additively. Implications of these results for models of modifier gene action are discussed.

Patient complaints of dental malpractice in Denmark 1983-86

A system for handling complaints of dental malpractice was established in 1983 in an agreement between the Danish Dental Association and the National Health Insurance. Description is given of the system comprising county dental complaints boards and a national dental complaints board. Reports of all complaints directed to the boards during the first 3 1/2 years were analyzed: 533 complaints to the county boards and 111 appeals to the national board. The complaints corresponded to 5 complaints per 100 dentists per year with considerable regional variation. Most complaints were reported in fixed and removable prosthetics, and most claims were of an economic nature. Almost two-thirds of the complaints were supported by the boards. Themes for further study as well as certain problems concerning consumer satisfaction weighed against the responsibility to survey dentists' work are pointed out.

Papillomavirus sequences integrate near cellular oncogenes in some cervical carcinomas

The chromosomal locations of cellular sequences flanking integrated papillomavirus DNA in four cervical carcinoma cell lines and a primary cervical carcinoma have been determined. The two human papillomavirus (HPV) 16 flanking sequences derived from the tumor were localized to chromosome regions 20pter----20q13 and 3p25----3qter, regions that also contain the protooncogenes c-src-1 and c-raf-1, respectively. The HPV 16 integration site in the SiHa cervical carcinoma-derived cell line is in chromosome region 13q14----13q32. The HPV 18 integration site in SW756 cervical carcinoma cells is in chromosome 12 but is not closely linked to the Ki-ras2 gene. Finally, in two cervical carcinoma cell lines, HeLa and C4-I, HPV 18 DNA is integrated in chromosome 8, 5' of the c-myc gene. The HeLa HPV 18 integration site is within 40 kilobases 5' of the c-myc gene, inside the HL60 amplification unit surrounding and including the c-myc gene. Additionally, steady-state levels of c-myc mRNA are elevated in HeLa and C4-I cells relative to other cervical carcinoma cell lines. Thus, in at least some genital tumors, cis-activation of cellular oncogenes by HPV may be involved in malignant transformation of cervical cells.

Different human cervical carcinoma cell lines show similar transcription patterns of human papillomavirus type 18 early genes

Transcription of human papillomavirus type 18 (HPV18) DNA in the human cervical carcinoma cell lines HeLa, C4-1 and SW756 was studied by nucleotide sequence analysis of HPV18-positive cDNA clones isolated from a HeLa, C4-1 and SW756 cDNA library, respectively, and the cDNA sequences were used to predict the potential encoded proteins. The cDNA clones from all three cell lines were found to be derived from virus-cell fusion transcripts in which 3'-terminal host cell sequences (different for each cell line) were spliced to 5'-terminal exon sequences from the HPV18 E6-E7-E1 region. Three different types of cDNA clones can be distinguished according to the splicing patterns observed in the 5' terminal HPV18 sequences. They carry as potential protein-coding regions the HPV18 specific open reading frames E6 and E6* (generated by splicing and identical with E6 up to the E6* splice junction), E7 and E1 (only in HeLa). Translation of specific cellular genes from the chimeric viral-cellular transcripts seems to be unlikely. The mapping of the 5'-ends of the virus-cell fusion transcripts indicates that transcription is initiated at a viral promoter. The similar patterns of HPV18 transcription in the three different cervical carcinoma cell lines suggest a functional role of HPV18 early genes for the malignant phenotype of these cells.

The nucleotide sequence and genome organization of human papilloma virus type 11

The complete nucleotide sequence of human papilloma virus type 11 (HPV11) DNA (7931 bp) was determined. HPV11 DNA which has been isolated from laryngeal papillomas and from genital warts (condylomata acuminata) shows a high degree of sequence homology to HPV6b (82%). The arrangement of open reading frames is very similar to HPV6b, the homology of the deduced amino acid sequences varies between 58 and 92%. Characteristic features of the noncoding region between the L1 and E6 open reading frames is an AT-rich domain of about 200 bp with extended stretches of alternating thymine-purine bases and a 12-bp inverted repeat element ACCG NNNN CGGT arranged in tandem upstream of the putative early promoter TATA box.