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S Hornung

Publications and source records attributed to S Hornung.

At least 19 recordsLinked to original sources
PubMed2000

Complete nucleotide sequence of the Oenothera elata plastid chromosome, representing plastome I of the five distinguishable euoenothera plastomes.

We describe the 159,443-bp [corrected] sequence of the plastid chromosome of Oenothera elata (evening primrose). The Oe. elata plastid chromosome represents type I of the five genetically distinguishable basic plastomes found in the subsection Euoenothera. The genus Oenothera provides an ideal system in which to address fundamental questions regarding the functional integration of the compartmentalised genetic system characteristic of the eukaryotic cell. Its highly developed taxonomy and genetics, together with a favourable combination of features in its genetic structure (interspecific fertility, stable heterozygous progeny, biparental transmission of organelles, and the phenomenon of complex heterozygosity), allow facile exchanges of nuclei, plastids and mitochondria, as well as individual chromosome pairs, between species. The resulting hybrids or cybrids are usually viable and fertile, but can display various forms of developmental disturbance.

Base Sequence↗
PubMed1996

Sequence variation in the putative replication origins of the five genetically distinct basic Euoenothera plastid chromosomes (plastomes).

Approximately 4,200 nucleotides of the 16S/23S rDNA spacer and the 5' region flanking the rrn operon of the plastid chromosomes representing the five basic, phylogenetically related Euoenothera plastomes were sequenced and compared. The sequences that harbor the putative replication origins are almost identical except for a 785-bp intercistronic segment between the genes for the 16S rRNA and trnI. Differences are mainly caused by insertions/deletions and duplications; the predicted potential for formation of quite extensive secondary structure differs among the plastomes. Unexpected intraplastome variation has also been noted. Furthermore, the sequence-based and published genetically deduced plastome pedigrees differ significantly.

Chromosomes↗
PubMed1987

Linkage disequilibrium of plasminogen polymorphisms and assignment of the gene to human chromosome 6q26-6q27.

Linkage disequilibrium was observed between newly identified DNA polymorphisms and a previously described protein polymorphism for plasminogen. This finding implies that the two types of polymorphisms describe variation at the same locus. The plasminogen gene was mapped to chromosomal bands 6q26-q27 using somatic-cell hybrids and in situ hybridization. Linkage disequilibrium between protein and DNA polymorphisms has utility in substituting for protein typing in instances where only DNA samples are available, such as from deceased individuals or extinct species. The technique may be useful when cross-hybridizing sequences make the interpretation of Southern blot patterns difficult and may obviate the need for extensive DNA sequencing. In some cases, disequilibrium may provide information useful for determining the appropriate direction for chromosome walks from a marker locus to a target locus.

Alleles↗
PubMed1985

The association of age, flying time, and aircraft type with hearing loss of aircrew in the Israeli Air Force.

Exposure to aircraft (A/C) noise is considered to be one of the factors which causes permanent hearing threshold shifts among military aircrew. Consequently most studies, dealing with this field of evaluation, fail to focus on the contribution of other elements, especially biological (physiological) ones. We, therefore, decided to evaluate the effect of the subject's age on this process. Audiometric records of 777 aircrew members within the Israeli Air Force were examined. The average age was 27.2 +/- 5.2 years. The individual files were composed of all yearly audiograms from time of recruitment to present, personal information, recorded flight time and type of A/C flown (i.e., rotary-wing and fighter, transport and light fixed-wing aircraft). Hearing loss was studied using two criteria (a. USAF criteria; b. acoustic trauma criteria we devised). The significance of each of the factors was analysed by using uni- and multivariate analysis (Pearson correlation and stepwise multiple regression). A progressive linear correlation between age and hearing loss was exhibited (p less than 0.001). The results suggest that the age of the subject is strongly correlated with values of hearing threshold shift, while A/C type and accumulated time played a minor role.

Adolescent↗
PubMed1984

Linkage disequilibrium and evolutionary relationships of DNA variants (restriction enzyme fragment length polymorphisms) at the serum albumin locus.

Four additional DNA variants (restriction enzyme fragment length polymorphisms) making a total of eight polymorphic sites at the human albumin locus have been identified. These eight sites were found after screening 689 of 20,000 nucleotides by using cDNA probes for albumin with 27 different restriction enzymes. One in 85 nucleotides was therefore potentially polymorphic. The average nucleotide diversity between any two randomly chosen chromosomes was calculated to be 1/500. We observed marked linkage disequilibrium between the eight variants. Only 7 haplotypes among 256 possible combinations were observed in 160 chromosomes from Caucasoids, Blacks, and Asians. Two haplotypes were found in all three human races, indicating that their origin predated human racial divergence. The three rarest haplotypes appear to represent recombinational events between the more common haplotypes. All crossovers occurred in the same general region. Studies of several nonhuman primates indicated that the origin of one haplotype predated the human-African ape divergence. Although it is not possible to rule out maintenance of this tight linkage by selection or fixation, it is suggested that the limited number of haplotypes at the chromosomal site of the albumin gene near the centromere of chromosome 4 may be the result of decreased recombination.

Animals↗
PubMed1984

Bone conduction evaluation related to mastoid surgery.

The bone conduction threshold changes of 97 patients (100 ears) who underwent mastoid surgery were determined by comparing the last preoperative audiogram with the 1 year postoperative audiogram. Three types of mastoid surgery were evaluated: radical mastoidectomy, modified radical mastoidectomy, and intact wall atticomastoidectomy. The average three speech frequency preoperative bone conduction threshold was 17.4 dB (S.D. 11.5) in the radical mastoidectomy group, 10.1 dB (S.D. 9.6) in the modified radical mastoidectomy group, and 10.7 dB (S.D. 8) in the intact wall atticomastoidectomy group. The difference between the average three speech frequency preoperative bone conduction threshold of the radical mastoidectomy group differed significantly when compared to the modified radical mastoidectomy or intact wall atticomastoidectomy group. The postoperative average three speech frequency bone conduction threshold did not change significantly following the three surgical procedures evaluated.

Adult↗
PubMed1984

Medical air evacuation during the Lebanon War, 1982.

During the Lebanon War, 1982, 85% of the Israel Defence Forces casualties were airlifted from the battle zone by means of the aeromedical evacuation (AME) network of the Air Force. The rescue helicopter was the first point of medical contact for 4.4% of the casualties. A summary is presented of the types of aircraft used in AME and the number of casualties carried in the various flights. A brief description is also given of a new addition to the intensive care capabilities of AME helicopters: the air mobile life support unit used in combat for the first time during this war.

Aircraft↗
PubMed1983

Plasma paraoxonase polymorphism: a new enzyme assay, population, family, biochemical, and linkage studies.

Plasma paraoxonase hydrolyzes paraoxon, the principal metabolite of the insecticide parathione. A genetic polymorphism for enzyme activity has been previously demonstrated. We describe a new assay based on the differential inhibition by EDTA of plasma paraoxonase from persons with the high-activity allele (PX*H) that suggests a trimodality of activity levels in population studies. The gene frequency of the low activity allele (PX*L) in 531 Seattle blood donors of European origin was .7207. Family studies were consistent with codominant autosomal inheritance of two alleles, PX*L (low) and PX*H (high), coding for products with different activity levels. Biochemical measurements of sera from presumed homozygotes for the two different alleles revealed minor physicochemical differences suggestive of a structural difference between the allelic products. No evidence for linkage of the paraoxonase locus with any of 19 polymorphic markers would be detected.

Adolescent↗
PubMed1978

[Consulting office tissue banks (author's transl)].

The technicalities of obtaining graft tissues and the methods of preserving homograft ossicles and cartilage are described. The chemical and biological problems of tissue banks are discussed practically in relation to published experiences of others. The techniques for use of homograft ossicles in tympanoplasty surgery are described. The comparative ease of preparation and preservation of homograft ossicles and hyaline cartilage justifies the establishment of tissue banks in the practice of the private otologist.

Cartilage↗
PubMed1978

[A clinical study on allogenetic ossicle-implantation (author's transl)].

Here we report a first three years clinical experience with allogenetic ossicles in middle ear surgery. The several allogenetic implants in tympanoplasty type III are coordinated to symbolic abbreviations for documentation. The technique and biology of Cialit-preservation is summarized. Findings and results vindicate the application of allogenetic ossicles outside large ENT hospitals too.

Cholesteatoma↗