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PubMed1979

Familial, balanced insertional translocation of chromosome 7 leading to offspring with deletion and duplication of the inserted segment, 7p15 leads to 7p21.

We report an uncle and niece with duplication and deletion, respectively, of segment 7p15 leads to 7p21 originating from a balanced, intrachromosomal insertion in their mothers. The proposita had prenatal and postnatal growth deficiency, retarded psychomotor development, microcephaly, wide cranial sutures, ocular hypertelorism, small palpebral fissures, apparently low-set and malformed ears, cleft palate, congenital heart defect, hypoplasia of the distal phalanx of first fingers, rocker-bottom feet, persistent cloaca, and imperforate anus. She died at three months. Her maternal uncle has duplication of this segment and is alive at 32 years. He has severe mental deficiency, but normal growth; communicating hydrocephalus was diagnosed at three months.

Abnormalities, Multiple↗
PubMed1975

Patient package inserts. II. Toward a rational patient package insert.

Analysis of the response to a questionnaire on various aspects of drug information showed several significant trends. The importance of the physician as an information source varied directly with age and inversely with educational level of patients. The doctor's importance as a source of information was also greater for those who visited physicians' offices or clinics more and if they were on long-term treatment. Younger persons, those with higher levels of education, and those who were not in regular contact with a physician placed greater importance on non-physician sources. Persons consulting physicians regularly desired less information and knew less about drugs than those who did not regularly see a physician. These findings suggest that the educational role of the physician could be improved and should be directed particularly at the low-income, older patient. In the design of the package insert, particular attention should be given to self-prescribed medications where no other information sources will be operating.

Adult↗
PubMed1988

Combined endoscopic and percutaneous stent insertion to overcome a problem of percutaneous stent insertion.

Non-operative stent insertion is a well-accepted means of palliating malignant biliary obstruction. The endoscopic approach is often considered the procedure of choice, with the percutaneous technique reserved for endoscopy failures. We recently encountered a patient in whom both techniques proved unsuccessful initially, and in whom palliation was finally achieved by means of a combined endoscopic and percutaneous transhepatic procedure.

Aged↗
PubMed1991

Occurrence and stability of insertion sequences in Mycobacterium tuberculosis complex strains: evaluation of an insertion sequence-dependent DNA polymorphism as a tool in the epidemiology of tuberculosis.

In this study we established the usefulness of DNA fingerprinting for the epidemiology of tuberculosis on the basis of the DNA polymorphism generated by the insertion sequence (IS) IS986. Although clinical isolates of Mycobacterium tuberculosis displayed a remarkably high degree of restriction fragment length polymorphism, we showed that transposition of this IS element is an extremely rare event in M. tuberculosis complex strains grown either in vitro or in vivo for long periods of time. The M. tuberculosis and Mycobacterium africanum strains tested in this study contained 6 to 17 IS copies. In the Mycobacterium bovis strains, the copy numbers ranged between 1 and 5, and all 27 M. bovis BCG strains investigated invariably contained a single IS copy. This copy was located at a unique chromosomal position, reinforcing the idea that the frequency of IS transposition is very low in M. tuberculosis complex strains. Various microepidemics are described in which each microepidemic corresponds to a particular fingerprint type. The extent of similarity between Dutch and African strains was quantitatively assessed by computer-assisted analysis of DNA fingerprints. The results indicate that M. tuberculosis strains from regions in central Africa, where tuberculosis is highly prevalent, are generally more related to each other than isolates from the Netherlands, where the transmission rate is low and where the majority of the tuberculosis cases are presumed to be the result of reactivation of previously contracted M. tuberculosis infections.

Africa↗
PubMed1991

Electrocardiographic body surface potential mapping in the Wolff-Parkinson-White syndrome. Noninvasive determination of the ventricular insertion sites of accessory atrioventricular connections.

BACKGROUND: A reliable, noninvasive procedure to determine the location of accessory atrioventricular connections in patients with Wolff-Parkinson-White syndrome would add an important diagnostic tool to the clinical armamentarium. METHODS AND RESULTS: Body surface potential mapping (BSPM) using 180 electrodes in various-sized vests and displayed as a calibrated color map was used to determine the ventricular insertion site of the accessory atrioventricular (AV) connections in 34 patients with Wolff-Parkinson-White syndrome. Attempts were made to determine the 17 ventricular insertion sites described by Guiraudon et al. All 34 patients had an electrophysiologic study (EPS) at cardiac catheterization, and 18 had surgery so the ventricular insertion sites could be accurately located using EPS at surgery. A number of physiologic observations were also made with BSPM. CONCLUSIONS: The following conclusions were drawn: 1) BSPM using QRS analysis accurately predicts the ventricular insertion site of accessory AV connections in the presence of a delta wave in the electrocardiogram; 2) the ventricular insertion sites of accessory AV connections determined by BSPM and by EPS at surgery were identical or within one mapping site (1.5 cm or less) in all but four of 18 cases; three of the four exceptions had more than one accessory AV connection, and the other had a very broad ventricular insertion; 3) BSPM and EPS locations of the accessory AV connections correlated very well in the 34 cases despite the fact that BSPM determines the ventricular insertion site and EPS determines the atrial insertion site of the accessory AV connection; 4) as suggested by the three cases of multiple accessory AV connections, EPS and BSPM may be complementary since BSPM identified one pathway and EPS identified the other (in the case with a broad ventricular insertion, BSPM and EPS demonstrated different proportions of that insertion); 5) BSPM using ST-T analysis is very much less accurate in predicting the ventricular insertion site of accessory AV connections unless there is marked preexcitation; 6) standard electrocardiography using the Gallagher grid methodology (but with no attempt at stimulating maximal preexcitation) was not as accurate as QRS analysis of BSPM in predicting the ventricular insertion site of the accessory AV connection; however, exact comparison is hampered by the different number and size of the Gallagher and Guiraudon insertion sites; 7) BSPM using QRS analysis appears to be very accurate in predicting right ventricular versus left ventricular posteroseptal accessory AV connections; 8) typical epicardial right ventricular breakthrough, indicative of conduction via the specialized AV conduction system, occurs in all patients with left ventricular free wall accessory AV connections; 9) epicardial right ventricular breakthrough was not observed in cases with right ventricular free wall or anteroseptal accessory AV connections; 10) epicardial right ventricular breakthrough can occur in the presence of posteroseptal accessory AV connections, whether right or left ventricular; and 11) the delay in epicardial right ventricular breakthrough in cases with left ventricular insertion may provide a marker to estimate the degree of ventricular preexcitation.

Adult↗
PubMed1992

Effects of P element insertions on quantitative traits in Drosophila melanogaster.

P element mutagenesis was used to construct 94 third chromosome lines of Drosophila melanogaster which contained on average 3.1 stable P element inserts, in an inbred host strain background previously free of P elements. The homozygous and heterozygous effects of the inserts on viability and abdominal and sternopleural bristle number were ascertained by comparing the chromosome lines with inserts to insert-free control lines of the inbred host strain. P elements reduced average homozygous viability by 12.2% per insert and average heterozygous viability by 5.5% per insert, and induced recessive lethal mutations at a rate of 3.8% per insert. Mutational variation for the bristle traits averaged over both sexes was 0.03Ve per homozygous P insert and 0.003Ve per heterozygous P insert, where Ve is the environmental variance. Mutational variation was greater for the sexes considered separately because inserts had large pleiotropic effects on sex dimorphism of bristle characters. The distributions of homozygous effects of inserts on the bristle traits were asymmetrical, with the largest effects in the direction of reducing bristle number; and highly leptokurtic, with most of the increase in variance contributed by a few lines with large effects. The inserts had partially recessive effects on the bristle traits. Insert lines with extreme bristle effects had on average greatly reduced viability.

Animals↗
PubMed1992

Structural and energetic differences between insertions and substitutions in staphylococcal nuclease.

In a previous study, the small protein staphylococcal nuclease was shown to readily accommodate single alanine and glycine insertions, with average losses in stability comparable to substitutions at the same sites (PROT. 7:299-305, 1990). To more fully explore this unexpected adaptability to changes in residue spacing, 2 double amino acid insertions (alanyl-glycine, glycyl-glycine) and 3 additional single amino acid insertions with dissimilar side chains (proline, leucine, and glutamine) were constructed at 10 of the sites previously studied. At 8 of these sites, the type of amino acid side chain on the inserted residue significantly influenced the stability of the mutant protein. However, at 9 of the 10 sites, the double insertions were found to be no more destabilizing than the single alanine or glycine insertions. In contrast, double substitution mutations of staphylococcal nuclease, which replace two adjacent residues with alanine, do not show this striking degree of non-additivity. A comparison of the effects of single glutamine and single glycine insertions with alanyl-glycine insertions indicates that insertion of alanine into the peptide backbone is, on average, less destabilizing than appending the equivalent atoms onto the side chain of a glycine insertion. To explain their very different energetic effects, we propose that, unlike most substitutions, the inserted residue(s) must induce lateral displacements of the polypeptide chain, forcing the folded conformation away from that of wild type. The resulting obligatory shifts in the positioning of residues flanking the insertion generate a large number of degrees of freedom around which the mutant structure can relax.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine↗
PubMed1979

Expression of ribosomal DNA insertions in Drosophila melanogaster.

Approximately half of the ribosomal genes on the X chromosome of Drosophila melanogaster are interrupted by an insertion of type 1. Nuclear RNA from D. melanogaster embryos was transferred to DBM paper and hybridized with cloned type 1 insertion sequences. With a DNA fragment derived specifically from large insertions, transcripts were detected between 5 and 10 kb. These insertion transcripts represent less than one RNA molecule per nucleus, which is more than three orders of magnitude below the concentration of nascent rRNA chains, as determined by kinetics of hybridization. With a DNA fragment derived from the right end of large insertions which is also complementary to short insertions, more discrete RNA bands appeared with sizes between 1 and 8.5 kb, representing altogether about 13 RNA molecules per nucleus. Insertion transcripts large enough to be potential precursors to 28S rRNA represent less than one molecule per nucleus. It was shown by sandwich hybridization that at least some of the insertion transcripts are derived from rDNA. No significant difference was found between insertion transcripts in RNA extracted from ovaries, embryos, larvae, pupae or adult flies. Unless a mechanism other than splicing is involved, ribosomal genes with insertions cannot contribute significantly to the synthesis of 28S rRNA. A cytoplasmic RNA approximately 1 kb long, which is complementary to a short insertion and to ribosomal gene sequences flanking both sides of the insertion, was found. The abundance of this short unspliced RNA is about 50 molecules per embryo cell.

Animals↗
PubMed1991

Tn554 inserts in methicillin-resistant Staphylococcus aureus from Australia and England: comparison with an American methicillin-resistant group.

We have compared methicillin-resistant (Mcr) Staphylococcus aureus isolates from Australia, the UK and the USA with regard to chromosomal inserts of the macrolides-lincosamides-streptogramin B (MLS)-resistance transposon Tn554. The American isolates were known to have a distinctive Tn554 insert, designated insert 6, which was closely associated epidemiologically with the methicillin-resistance phenotype. Southern blots of DNA from Australian and London, UK Mcr isolates were hybridized with a range of probes related to Tn554. The isolates had similar or identical Tn554 inserts, and we consider them to be a single group, designated 'Australondon'. Australondon isolates were compared in detail with a deletion mutant, ANS62, that had lost the methicillin-resistance determinant mec, plus other resistance determinants resident in the mec region of the chromosome, and with an American Mcr isolate containing Tn554 insert 6. The Australondon isolates had three Tn554 inserts. Sequence analysis with the polymerase chain reaction showed that all of these inserts differed from classical Tn554 in that the 3'-terminal residues of the transposons were reverse complements of the usual GATGTA. One of the Australondon inserts, designated 6B, closely resembled Tn554 insert 6 in the sequence of its left flanking chromosomal DNA. This insert was found to abut the deletion from the mec region which results in strain ANS62. We infer that Tn554 insert 6B is part of the mec region of the chromosome in Australondon isolates, supporting the idea that insert 6 of the American isolates is also part of this chromosomal region.

Australia↗
PubMed1991

Investigation of early surface delamination observed in retrieved heat-pressed tibial inserts.

The objective was to examine possible reasons for delamination observed in tibial inserts of the porous-coated anatomic (PCA) knee replacement. To date, 33 PCA inserts have been forwarded to the authors' labs. Of these 33, 52% showed severe delamination within four years of implantation. Visual, structural, and mechanical analyses were conducted and data compared on the heat-pressed PCA type and the common machined inserts. Twenty inserts of the two different types were examined. Visual data using polarized light microscopy showed the presence of a surface layer separated from the middle region of the heat-pressed inserts by a line of demarcation 250-580 microns beneath the articulating surface. This anomaly was not observed in machined inserts. Structural analysis showed the new heat-pressed inserts had increased crystallinity in the surface layer when compared to new machined inserts. The retrieved heat-pressed inserts showed increased crystallinity in the surface and middle regions. There was a slight increase in surface crystallinity in the retrieved machined inserts. Microhardness data showed that there was an increased hardness associated with the crystallinity seen on the heat-pressed inserts. Orthopedic surgeons should be aware of early delamination and surface failure in heat-pressed inserts.

Hardness↗
PubMed1989

Characterization of a nondeleterious L1 insertion in an intron of the human factor VIII gene and further evidence of open reading frames in functional L1 elements.

We have characterized an insertional event in IVS-10 of the factor VIII gene in a pedigree containing a hemophilia A patient (JH-25). The inserted DNA is a 5' truncated L1 element that is 681 bp long followed by a 3'66-bp poly(A) tract. The L1 element is inserted 154 bp 5' to the start of exon 11 and is flanked by a 13- to 17-bp target site duplication. The L1 insertion is present in four generations of the patient's family. The maternal grandfather who carries the insertion does not have hemophilia A, indicating that the insertion is not the cause of hemophilia A in the patient. We have sequenced this insertion and two previously reported de novo L1 insertions in the factor VIII gene in patients JH-27 (3785 bp) and JH-28 (2132 bp). The three nucleotide sequences differ by 0.2-0.8%. All three of these L1 insertions have open reading frames (ORFs) (1192, 642, and 157 aa) and the three derived amino acid sequences are 98-99% identical. The previously reported sequence similarity between L1 3' ORFs and the polymerase domain of reverse transcriptases is maintained in the ORFs of the JH-27 and JH-28 L1 insertions. The presence of open reading frames and the close sequence similarity of these recently inserted L1 elements provide indirect evidence for the existence of a set of functional L1 elements that encode one or more proteins necessary for their retrotransposition.

Base Sequence↗
PubMed1986

Large, unstable inserts in the chromosome affect virulence properties of uropathogenic Escherichia coli O6 strain 536.

The hemolytic, uropathogenic Escherichia coli 536 (O6:K15:H31) contains two inserts in its chromosome (insert I and insert II), both of which carried hly genes, were rather unstable, and were deleted spontaneously with a frequency of 10(-3) to 10(-4). These inserts were not found in the chromosome of two nonhemolytic E. coli strains, whereas the chromosomal sequences adjacent to these inserts appeared to be again homologous in the uropathogenic and two other E. coli strains. Insert I was 75 kilobases in size and was flanked at both ends by 16 base pairs (bp) (TTCGACTCCTGTGATC) which were arranged in direct orientation. For insert I it was demonstrated that deletion occurred by recombination between the two 16-bp flanking sequences, since mutants lacking this insert still carried a single copy of the 16-bp sequence in the chromosome. Both inserts contained a functional hemolysin determinant. However, the loss of the inserts not only affected the hemolytic phenotype but led to a considerable reduction in serum resistance and the loss of mannose-resistant hemagglutination, caused by the presence of S-type fimbriae (sfa). It is shown that the Sfa-negative phenotype is due to a block in transcription of the sfa genes. Mutants of strain 536 which lacked both inserts were entirely avirulent when tested in several animal model systems.

Adhesins, Escherichia coli↗
PubMed1990

Package inserts for antihypertensive drugs: use by the patients and impact on adverse drug reactions.

In Belgium, all dispensed drugs are provided with package inserts. Traditional physician-orientated inserts are gradually being replaced by patient package inserts (PPIs). The present survey is focused on the use of inserts for antihypertensive drugs and their impact on the reported occurrence and attribution of adverse drug reactions (ADRs). A group of 28 general practitioners (GPs) from the Flemish part of Belgium collected data from 702 hypertensive patients. Each participating GP submitted a consecutive sample of his patients to an interview in the Spring 1989, when 25% of the antihypertensive specialties carried a PPI-version. 1049 prescriptions for antihypertensive drugs had been dispensed. Two thirds of the patients, mostly those with a higher educational level, had read the package inserts. PPIs accounted for 16% of the inserts, and they had not been read significantly more than the traditional inserts. Reporting by the patients of possible drug-related health problems (spontaneously + after having heard the items on a check-list) was not affected by reading the insert or by the type of insert. However, the PPI did bring about spontaneous reporting, especially by patients with a low educational level. Attribution of at least one health problem to the medication was not affected by reading in itself but by the type of insert. Attribution was higher when the patient had received a PPI, except in the case of highly educated patients. Spontaneous reporting and attribution of health problems to the medications prescribed was found more frequently among patients with higher education, who did not seem to need a PPI to recognize problems as being drug-related.

Antihypertensive Agents↗
PubMed1979

Nature of the regions involved in the insertion of newly synthesized protein into the outer membrane of Escherichia coli.

Outer membrane proteins are synthesized by cytoplasmic membrane-bound polysomes, and inserted at insertion sites which cover about 10% of the total outer membrane when cells grow with a generation time of 1 h. A membrane fraction enriched in outer membrane insertion regions was isolated and partly characterized. The rat at which newly inserted proteins are transferred from such insertion regions into the rest of the outer membrane was found to be very fast; the new protein content of insertion regions and that of the remaining outer membrane equilibrate completely within about 20 s at 25 degrees C. Given the rather rigid structure of the outer membrane and the multiple interactions between outer membrane components and the murein layer, lateral diffusion of newly inserted proteins from insertion sites to the remaining outer membrane is not likely to explain this rapid equilibration. Instead, the data support a model in which insertion regions move along the cell surface, leaving behind stationary, newly inserted outer membrane proteins.

Bacterial Proteins↗
PubMed1979

Specificity of insertion by the translocatable tetracycline-resistance element Tn10.

Genetic analysis of 131 independent transpositions of the tetracycline-resistance element Tn10 from a single site in phage P22 into the histidine operon of Salmonella typhimurium reveals that Tn10 insertions are not randomly distributed along this chromosomal target. The insertions occur in 22 different "clusters"; insertions within each cluster are very tightly linked in recombination tests. Tn10 insertions are not evenly distributed among the identified clusters. The existence of these clusters suggests that this chromosomal target contains particular genetic signals that guide Tn10 to particular preferred positions for insertion. Insertions within each cluster occur in both orientations with roughly equal frequency.--The relationship among different insertions within each cluster has been examined. The resolution of genetic mapping places an upper limit of about 50 basepairs on the distance between different insertions within a cluster. Different insertions within a cluster usually have the same reversion frequency; however, heterogeneity in reversion frequency has been detected in at least two clusters. For most clusters, the available data are consistent with the simple possibility that all insertions within a cluster are at identical positions; however, the data do not exclude other possibilities.

Base Sequence↗