[Teleradiology--blessing or curse? 4 years routine in the North Hessia teleradiology data network]. / Teleradiologie--Segen oder Fluch? Vie Jahre Routine im Teleradiologischen Datennetz Nordhessen.

Several hospitals in northern Hessen, not having their own radiology departments, want to run CT-scanners with the goal of improving medical quality. They requested co-operation from the Radiological Institute in the Hardtwaldklinik I in Bad Zwesten. Therefore a teleradiological network was developed, which enables the exchange of radiological-images and -reports between 19 hospitals today. An elementary requirement for this co-operation is an efficient and functional computer infrastructure and verified co-operation contracts. The conception, structure and development of the program, as well as associated difficulties are presented and discussed from different perspectives in the light of the controversy among experts. The results, experiences and benefits gained in four years, in which the teleradiological network of northern Hessen has been in place, demonstrate the importance and possibilities of teleradiology as an element of telemedicine. Teleradiology/telediagnostics improves the quality of patient care in smaller hospitals located in less-populated areas and present possibilities to optimize and integrate health care structures, taking economic considerations into account.

Identification of a 1.2 Kb cDNA fragment from a region on 9p21 commonly deleted in multiple tumor types.

Chromosome band 9p21 is a frequent target of homozygous deletion in many tumor types. Putative tumor suppressor genes, CDKN2A (p16), p14(ARF) and CDKN2B (p15), were localized to 9p21. However, there have been reports that suggest that there may be other genes targeted for inactivation in the region. We have developed a method to search for transcribed sequences within large genomic regions. We tested our approach in a 100-kilobase region on 9p21, which is 40 kilobases telomeric to CDKN2A. The method, termed expressed sequence selection (ESS), resulted in the isolation of genomic fragments known to be from 9q21 that are homologous to transcribed sequences. One fragment was used to obtain a 1.2 kilobase cDNA. The sequence of the 5' half of the cDNA was almost identical to exons 3-5 of the MTAP gene, which maps to chromosome band 9p21. The 3' portion of the cDNA had sequence homology to the ALA gene, which maps to chromosome arm 9q. Using Northern blot analysis, the 1.2 Kb cDNA identified several widely expressed transcripts ranging from 1 Kb to 8.5 Kb and displayed a complex pattern of alternative splicing in which certain exons of the 1.2 Kb cDNA are excluded from some of the splice products. Using cancer tissue Northern blots, we could show that all of the transcripts are absent from a leukemia cell line and a lung cancer cell line (K562, A549) with homozygous, genomic deletions within chromosome band 9p21. In addition, the 7 Kb transcript is also absent from two additional tumor cell lines (Molt4, a leukemia derived cell line, and in G361, a melanoma derived cell line) with homozygous deletions. Further investigation will determine whether the difference in the expression pattern between the 7 Kb transcript compared with the other sized transcripts could be due to specific targeting for alteration in certain tumor types.

Sociality in the spectral tarsier, Tarsius spectrum.

Recent studies indicate that many of the nocturnal prosimian primates are gregarious rather than solitary. This paper shows that the spectral tarsier is gregarious during its nightly activity period as well as in its sleeping tree. Using mist nets and radiotelemetry, focal follows were conducted on six groups at Tangkoko Nature Reserve in Sulawesi, Indonesia. During 442 focal follows, 1072 encounters between a focal adult group member and another adult were observed. The number of encounters ranged from as few as 0 to as many as 18 encounters per night. Intragroup encounters lasted from less than 1 min to as long as 3 hr 12 min. Nearly one-half of all social behavior occurred between adult females and males. There were also substantial rates of social interaction between the two adult females in one group, and between sub-adults of the opposite sex in neighboring groups.

Allocare in a nocturnal primate: data on the spectral tarsier, Tarsius spectrum.

Non-maternal infant care in many of the small-bodied New World primate species has been hypothesized by some researchers to be related to the high infant/adult weight ratio found in these species. The spectral tarsier, Tarsius spectrum, an Old World primate, has one of the highest infant/adult weight ratios of any primate, with infants weighing between 20-33% of adult weight at birth. On the basis of the hypothesized relationship between allocare and the infant/adult weight ratio, it is predicted that the spectral tarsier will also exhibit extensive allocaretaking behaviour. The results of this study indicate that although spectral tarsiers show care by male and female subadults as well as adult males, it is extremely limited compared to the extensive allocaretaking behavior observed in New World primate species such as Aotus and Callicebus. Spectral tarsier subadult females provide substantially more allocare to infants than do subadult males or adult males. Female subadults were observed sharing food, transporting, grooming, playing, alarm calling, baby-sitting and maintaining physical contact with infants more than other age/sex classes. Although the amount of allocare exhibited by adult males and subadult males was much less than that exhibited by female subadults, the data suggest that adult and subadult male spectral tarsiers do play a small part in the care and socialization of the infant. Adult males and subadult males were both observed occasionally engaging in allocaretaking behaviors such as grooming and playing, as well as frequently patrolling and defending the territory's boundaries. The results from this study suggest that although a high infant/adult weight ratio may be a prerequisite for selection to favor extensive allocare, it is not a causal factor. Additional research is needed in order to understand better the selective pressures involved and the costs and benefits of providing allocare to subadults and adult male spectral tarsiers.

Effects of radio transmitter weight on a small nocturnal primate.

An increasing number of primatologists have begun using radio telemetry to study the behavioral ecology of nocturnal prosimian primates. Radio telemetry has enabled the collection of data on these nocturnal and cryptic prosimians that was previously difficult or impossible to otherwise obtain. A critical assumption of studies employing radio telemetry is that the radio transmitters have no appreciable negative effects on the study animals and the data being collected are not being biased by the presence of radio transmitters. This assumption is made because comparable data from a non-radio-collared control group are impossible to obtain. In an attempt to determine the tolerable weight limit for radio collars for a small nocturnal primate, the spectral tarsier, Tarsius spectrum, a comparison of the behavior and body weight of individuals wearing collars of two different weights was conducted. This study was conducted in Tangkoko Dua Saudara Nature Reserve in Sulawesi, Indonesia. A total of 16 individuals from seven groups were trapped in mist nets, radio-collared, and observed using focal follow sampling between April 1994 and June 1995. Each individual was observed for 4-6 months depending on the life span of the radio-collar battery. The two radiocollar weights appeared not to affect spectral tarsiers differentially. Average body masses in neither set of subjects differed between the days collars were attached and 6 months later, when they were removed. No differences in activity patterns, home range size, or prey capture rate were detectable between subjects wearing the different transmitters. These results suggest that the heavier radio collars used in this study did not have any appreciable effects on the behavioral patterns of this primate.

Construction of a 2.8-megabase yeast artificial chromosome contig and cloning of the human methylthioadenosine phosphorylase gene from the tumor suppressor region on 9p21.

Many human malignant cells lack methylthioadenosine phosphorylase (MTAP) enzyme activity. The gene (MTAP) encoding this enzyme was previously mapped to the short arm of chromosome 9, band p21-22, a region that is frequently deleted in multiple tumor types. To clone candidate tumor suppressor genes from the deleted region on 9p21-22, we have constructed a long-range physical map of 2.8 megabases for 9p21 by using overlapping yeast artificial chromosome and cosmid clones. This map includes the type IIFN gene cluster, the recently identified candidate tumor suppressor genes CDKN2 (p16INK4A) and CDKN2B (p15INK4B), and several CpG islands. In addition, we have identified other transcription units within the yeast artificial chromosome contig. Sequence analysis of a 2.5-kb cDNA clone isolated from a CpG island that maps between the IFN genes and CDKN2 reveals a predicted open reading frame of 283 amino acids followed by 1302 nucleotides of 3' untranslated sequence. This gene is evolutionarily conserved and shows significant amino acid homologies to mouse and human purine nucleoside phosphorylases and to a hypothetical 25.8-kDa protein in the pet gene (coding for cytochrome bc1 complex) region of Rhodospirillum rubrum. The location, expression pattern, and nucleotide sequence of this gene suggest that it codes for the MTAP enzyme.

Probing protein-cofactor interactions in the terminal oxidases by second derivative spectroscopy: study of bacterial enzymes with cofactor substitutions and heme A model compounds.

Second derivative absorption spectra are reported for the aa3-cytochrome c oxidase from bovine cardiac mitochondria, the aa3-600 ubiquinol oxidase from Bacillus subtilis, the ba3-cytochrome c oxidase from Thermus thermophilis, and the aco-cytochrome c oxidase from Bacillus YN-2000. Together these enzymes provide a range of cofactor combinations that allow us to unequivocally identify the origin of the 450-nm absorption band of the terminal oxidases as the 6-coordinate low-spin heme, cytochrome a. The spectrum of the aco-cytochrome c oxidase further establishes that the split Soret band of cytochrome a, with features at 443 and 450 nm, is common to all forms of the enzyme containing ferrocytochrome a and does not depend on ligand occupancy at the other heme cofactor as previously suggested. To test the universality of this Soret band splitting for 6-coordinate low-spin heme A systems, we have reconstituted purified heme A with the apo forms of the heme binding proteins, hemopexin, histidine-proline-rich glycoprotein and the H64V/V68H double mutant of human myoglobin. All 3 proteins bound the heme A as a (bis)histidine complex, as judged by optical and resonance Raman spectroscopy. In the ferroheme A forms, none of these proteins displayed evidence of Soret band splitting. Heme A-(bis)imidazole in aqueous detergent solution likewise failed to display Soret band splitting. When the cyanide-inhibited mixed-valence form of the bovine enzyme was partially denatured by chemical or thermal means, the split Soret transition of cytochrome a collapsed into a single band at 443 nm.(ABSTRACT TRUNCATED AT 250 WORDS)

[Determination of the radiation imparted to patients in x-ray diagnosis--methods and results]. / Ermittlung der Strahlenbelastung der Patienten in der Röntgendiagnostik--Methoden und Ergebnisse.

The amount of radiation committed to the patient is best described by appropriate organ doses. Methods for determining such dose values are described. For x-ray investigations of the chest, thoracic and lumbar spine, pelvis and kidney (excretion urography) our own organ-dose values are compared with those from the literature.

[Computerized tomography studies of normal morphology and volumetry of parenchymatous epigastric organs in humans]. / Computertomographische Untersuchungen zur normalen Morphologie und Volumetrie parenchymatöser Oberbauchorgane des Menschen.

Variations in the area and dimensions of the liver and spleen in the craniocaudal direction show a similar behaviour despite individual differences in the size and shape of the organs. The liver has its largest areal extent in the upper half of the organ. In the case of the spleen, it is not possible for the largest areal extent to be assigned to a particular region of the organ. The 5-type liver classification of FROMMHOLD and KOISCHWITZ (1982) provided the basis for a study of the frequency distribution of those types among a total of 116 organs. Type 2 (location of the greater part of the liver to the right of the vertebral column) was found to be the most frequent type, whereas type 5 (left lobe of the liver larger than the right one) could not be found. Of the 183 splenic organs included in these studies, 21% showed lobulation and 6%, an accessory spleen. The morphological studies of 334 adrenal glands enabled the most frequent variants of form to be represented summarily. The determination of liver dimensions, which was done on 37 organs, yielded a mean value of 16.6 cm for the craniocaudal extent, 15.5 cm for the dorsoventral extent, and 16.6 cm for the lateromedial extent. From the examinations performed on 38 individuals it was possible to determine a mean value of 11.1 cm for the craniocaudal extent of the spleen, 11.8 cm for the anatomical length of the spleen, 10.4 cm for the width of the spleen, and 4.2 cm for the thickness of the spleen. The mean value of the width of pancreas was 20.5 mm at the head, 19.6 mm at the corpus, and 18 mm at the tail. The mean length of pancreas was of the order of 129 mm. These results were obtained from examinations made on 96 pancreatic organs. Evaluation of a total of 200 computer tomograms yielded mean values of 22 mm for the length. 14 mm for the width, and 5 mm for the leg thickness of the left adrenal gland. The respective mean values obtained for the right adrenal gland were 28 mm, 9 mm, and 4 mm respectively. Determination of the volume of liver on 37 organs yielded a mean value of 1,331 cm3. For the spleen, examinations performed on 38 organs showed the mean volume to be in the order of 169 cm3. For the volume of pancreas, a mean value of 40.4 cm3 was determined.

[Methodologic observations on the quantitative determination of uteroplacental perfusion]. / Methodische Betrachtungen zur quantitativen Bestimmung der uteroplazentaren Perfusion.

The determination of utero-placental perfusion by isotop methods is examined. Possible errors are discussed. The determination of placentaperfusion on the basis of the activity maximum is proposed as an alternative to evaluation methods used until now.