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K Paulsen

Publications and source records attributed to K Paulsen.

At least 19 recordsLinked to original sources
PubMed1993

Refined solution structure of the glucocorticoid receptor DNA-binding domain.

A refined solution structure of the glucocorticoid receptor DNA-binding domain (GR DBD) has been determined using two- and three-dimensional nuclear magnetic resonance (NMR) spectroscopy on an 15N-labeled GR DBD fragment in conjunction with distance geometry and simulated annealing calculations. Thirty structures of the fragment C440-R510 of the rat GR were calculated based on 906 distance constraints obtained from NOE intensities (168 intraresidue and 738 interresidue NOEs) and 43 dihedral constraints. Average atomic root mean square (rms) differences between the 24 best structures and their geometric average are 0.70 A for backbone atoms and 1.44 A for all heavy atoms. Several regions that were not well defined in a previous NMR structure determination of a similar protein fragment [Härd, T., Kellenbach, E., Boelens, R., Maler, B.A., Dahlman, K., Freedman, L.P., Carlstedt-Duke, J., Yamamoto, K.R., Gustafsson, J.-A., & Kaptein, R. (1990b) Science 249, 157-160] are now well-defined. The refined structure of the uncomplexed GR DBD is very similar to the crystal structure of GR DBD in a sequence specific DNA complex [Luisi, B. F., Xu, W. X., Otwinowski, Z., Freeman, L. P., Yamamoto, K. R., & Sigler, P. B. (1991) Nature 352, 497-505], in particular with regard to the presence and relative positions of secondary structure elements. The backbone atom rms difference between the average NMR solution structure and the crystal structure of the DNA-complexed GR DBD is 1.8 A. The most pronounced differences between the free and DNA-complexed states are found within the fragment C476-C482 in the second zinc-coordinating domain.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1987

Deletion of the DXS165 locus in patients with classical choroideremia.

Using various probes from the Xq21 region which is known to carry the choroideremia (tapetochoroideal dystrophy, TCD) locus, we have screened the DNAs from eight unrelated male choroidermia patients for microdeletions. In two of these patients, but not in any of 45 males tested as controls, lack of hybridization signals with probe plbD5 suggested a deletion encompassing the DXS165 locus and (part of) the TCD gene. Absence of additional clinical features in these patients and the fact that two closely linked, and probably flanking, TCD markers (DXYS1 and DXS72) are not deleted may indicate that the physical distance between the DXS165 locus and the TCD gene is small.

Choroid↗
PubMed1986

Regional localisation of X chromosome short arm probes.

Nine human X chromosome-specific clones have been isolated by screening an X-chromosomal genomic library with fetal muscle cDNA. Five of the clones have been localised to the short arm and four to the long arm. The short arm probes have been regionally assigned using a panel of somatic cell hybrids. They have been mapped further using a series of DNA samples from male patients with different deletions of the region Xp21, and having complex phenotypes including Duchenne muscular dystrophy. The use of these probes in the mapping of the short arm of the X chromosome is discussed.

Chromosome Banding↗
PubMed1981

The Matching Familiar Figures Test: a primary, secondary, and tertiary evaluation.

Analyzed the Matching Familiar Figures (MFF) Test, which has been employed by researchers to determine conceptual tempo, for potential use as a tool for the clinician. The literature indicates that the test is valid in terms of range and structural clarity of information provided. The psychological factors inherent in impulsivity are discussed, along with some significant implications of the MFF that justify its further development. Currently, the primary deficits are a lack of norms as well as an alternate form. Several crucial advantages of this test are listed that favor its use in a clinical environment.

Age Factors↗
PubMed1980

Impulsivity: a multidimensional concept with developmental aspects.

Fifty-five preschool children were administered a number of tests purported to measure impulsivity: Delay of Gratification, Walk-the-Line-Slowly, Matching Familiar Figures Test, Schenectady Kindergarten Rating Scales, a teacher rating scale, and the Porteus Maze Test. Analyses indicated that impulsivity is multidimensional, with age-, sex-, IQ-, and teacher-related types. The results suggested that multiple indices are essential to the measurement and study of impulsivity. An interaction between sex and age of child was also revealed with respect to type and rate of activity. While 3- and 4-year-old girls differ radically from boys in type and rate of motor activity (fine muscle vs. gross muscle), 5-year-olds were virtually identical.

Age Factors↗
PubMed1979

Construct validation of children's behavior problem dimensions: relationship to activity level, impulsivity, and soft neurological signs.

A construct validation study of dimensions of children's behavior problems was carried out with use of multiple linear regression. The Ss were 76 latency-aged boys in residential treatment. The dimensions involved were Conduct Disorder and Inadequacy-Immaturity. The predictor variables were activity level, impulsivity, and soft signs of neurological damage. Results indicated that Conduct Disorder was significantly predicted by activity level, in combination with impulsivity. Inadequacy-Immaturity was significantly predicted by activity level and soft signs. A third dimension, Personality Disorder, was found to be uncorrelated with the three predictor variables.

Child↗
PubMed1978

Reflection-impulsivity and level of maturity.

It was hypothesized that scores on the Matching Familiar Figures Test (MFF) are related to level of maturity. To test this hypothesis, 76 latency-aged boys in residential treatment were administered the MFF and a gross motor coordination test and were assessed for soft signs of neurological damage. Also included were age, IQ, and reading scores, along with ratings of behavior problems, activity, and impulsivity levels. A factor analysis yielded a factor (Factor II) consisting of MFF errors, age, soft signs of neurological damage, and gross motor coordination. Another factor (Factor IV) consisted of MFF errors and MFF latency. Factor IV provides support for the reflection-impulsivity construct, while Factor II may suggest that scores on the MFF are partially a function of physiological maturity and that errors contribute more than latency to the determination of reflection/impulsivity.

Child↗
PubMed1977

[High frequency cinematographic investigations of the mode of operation of common grinding instruments on bone and cartilage (author's transl)].

The mode of operation of grinding faces, rod diamonds and diamond grinding heads which are expecially employed in oto-surgery was investigated in slow motion pictures with the aid of high frequency cinematography. The R.P.M. ranged between 5,000-80,000, the picture frequency was usually 6,000 pictures per second. Full efficiency of the diamond grinding heads (DS) is only guaranteed by adequate flushing. Water stream flushing and drop flushing (drop sequence depending on R.P.M.) must be centered on the grinding head, as increased soiling due to filling of the diamond surface occurs otherwise. Because of the fixed mounting of the spray tube in the direction of the shaft, spray flushing is most useful, although not unsable for diamond faces. Due to its very fine-rough surface, the DS produces grinding dust by abrasion from the bone or cartilage which is readily distributed in the airspace over the whole working area. The same does also apply to finely atomized fluid sprays. Cutting is performed tangentially. The percussing DS touches the bone only with a small part of its surface and easily gets soiled. Depending on the R.P.M., the cutting speed was 10,000-80,000 R.P.M. These values also apply for the fluid dropping rate. Contrary to the rose bit or the surgical fraises, the DS got soiled more easily and produced definitely finer cuts.

Cartilage↗
PubMed1976

[High frequency cinematographic investigations of the mode of operation of common drilling instruments on bone and cartilage (author's transl)].

High frequency cinematographic films were made of the mode of operation of common oto-surgical drilling instruments on bone and cartilage. Rose bits and surgical fraises of different sizes were used at 5,000-80,000 R.P.M. The evaluation of the slow motion pictures was performed on the running films and by review of single frames. In detail: The preparation of the drilling head on the bone without simultaneous flushing leads to a filling of the cutting channel and decreased cutting. Drop flushing only prevents the increasing soiling of the drilling head if the drop sequence is rapid and which must be markedly increased with increasing R.P.M. of the drilling instrument. Flushing with a stream of water, which definitely prevents soiling, is preferable. Both drop flushing as well as the water stream must continuously wet the drilling head, i.e. must be absolutely centric in every case. Safest is the automatic spray flusing which is mounted on the handpiece, but which has so far not been used in oto-surgery. During the preparation, the air space of the working area is always filled with drilling dust or haze. Cutting is always performed tangenitally. The cutting speed lies between 2,9 m/s to 16 m/s. It depends on the R.P.M. of the drilling instrument. A drill head running out of true, even with a gently percussing shaft, touches the bone only with a part of its cutting surface which strikes more vigorously than desired and easily gets soiled, despite flushing. Cutting is therefore less and uncontrolled. An increased feeding energy (pressure on the support) in order to speed up cutting leads to heavy wear of the drilling instrument and unsafety in handling due to jumping of the drilling head. During each contact of a cutter with the bone, coarse fraises with low R.P.M. (5,000 R.P.M. = 83 R/s) show a short stopping of the rotation which results in a jerk and vibration of the whole preparation and can thus lead to a damage of the inner ear.

Bone and Bones↗
PubMed1976

[Progressive necrotizing otitis externa in diabetics with disorders of the cerebral nerves (author's transl)].

The disease occurs without exception in elderly diabetics. Pseudomonas aeruginosa (pyocyaneus) is always found in the secretion. In our reported case of a 71-year old man appeared in addition to a fetid, festering, granulating otitis externa, disturbances of swallowing, hoarseness and severe occipital headaches appear after five months. Neurologically, the N. glossopharyngeus, the N. recurrens and the N. hypoglossus were shown to be paretic. The inflammatory process has pushed forward via the bone of the auditory meatus on to the base of the skull to the jugular foramen and the foramen lacerum. Surgical removal of the inflammatory changes and subsequent treatment with carbenicillin is recommended as the treatment of choice.

Aged↗
PubMed1976

[Histological examinations about possible heat lesions of bone and cartilage during boring and grinding (author's transl)].

In skull bone and septum cartilage holes were bored with rose trepans and diamond cutters of various sizes (2-20) and at different revolutions (5,000-42,0000 rev/min) with and without the use of cooling fluid. The specimens were examined histologically. Borings with rose trepans without cooling fluid cause sometimes considerable heat lesions up to a depth of 30 mu. Bone shows the more severe lesions. The use of cooling fluid reduces the damage quite considerably (burns zone up to a maximum depth of 12 mu). In the normal range of up to 10,000 rev/min practically no heat lesions occur. In the high range above 20,000 rev/min the lesions are often only plaque-shaped. Water jet or spray cooling is superior to droplet cooling. Diamond cutters cause more severe lesions. Boring and grinding in the highest range (up to 300,000 rev/min) without cooling fluid cause very deep burns (up to 56 mu),

Bone and Bones↗
PubMed1976

[Bacterial airborne dispersal during the drilling of infected bone (author's transl)].

The hazards of infection by bacterial airborne dispersal secondary to drilling bone in the surgical treatment of infection of the air spaces of the skull were assessed experimentally. This included estimation of the furthest distance that the cooling fluid, using coloured water, and the bone chips of a dry petrous temporal bone can be thrown, and the spread of the fine dust produced by the drilling using a staph. albus suspension as the rinsing fluid. The drops and bone chips were flung to a distance of about 90 cm in the working area around a cutting burr rotating at 80 000 r.p.m. The fine dust thrown off by cutting and diamond burrs and the infected fluid mist stays suspended in the air for hours and can be carried across the whole room by air currents. The surgeon and operating theatre personnel are therefore always at risk of infection. Preventive measures are discussed.

Bacterial Infections↗
PubMed1976

[How important are lower tunnels in the cottle septoplasty? (author's transl)].

The Cottle method is the best for correction of anterior nasal septal deformities. Establishment of the lower tunnel however seems unadvisable because of the common damage to the nasopalatine nerve passing through the incisive foramen with occasional permanent sequelae. The procedure also is time-consuming. As a rule spurs or deviations can be dealt with after establishing upper tunnels without perforation of the mucoperichondrial or mucoperiosteal flaps. The method is described in details.

Cartilage↗
PubMed1976

[Experiences with a new bone drill for surgery of the ear and nose (author's transl)].

Surgical drilling similar to that developed by Kaltenbach and Voigt for bone work on the ear, nose, maxilla, hand and vertebrae can be used at up to 80,000 rev/min without undesirable heat production. Drill-bits with the normal shaft length of 45 mm remain steady at 80,000 rev/min, but drill-bits of 70 mm length sometimes vibrate. The size of drill head and rate of revolution in this respect are related proportionately especially with cutting as opposed to diamond drill-heads. In ear surgery this method is only suitable on certain conditions. In nasal surgery it is useful for the transverse osteotomy with a 45 mm long circular saw.

Ear↗
PubMed1975

[Measurement of sound transmitted through the body while drilling and grinding isolated petrous temporal bone (author's transl)].

Measurements of the effect of rotating drills and grinders on isolated fresh temporal bone on the sound transmitted through the body have not previously been made known. In contrast to measurement of air-conducted sound, they include the portion of sound which effects the hearing apparatus of the patient through the bone during the process of drilling the temporal bobe. Measurements were made with a calibrated acceleration pick-up in conjunction with a precision sound level meter (test amplifier with sound frequency analyser). The recording was made continuously between 20 Hz and 20 000 Hz. The range between 250 Hz and 8000 Hz was examined mathematically. Above 8000 Hz the curves dropped markedly, apart from a few exceptions. The level of the sound depends largely on the size of the drill bit, and consequently on the breadth and depth of the rotating cutting edges. The smaller drill heads produce a considerably smaller quantity of sound. The highest level of sound comes from the burrs and wing-cutters. The diamond head lies lower in the scale, but almost equals the effect of the steel drills. The speed of rotation of the drill head plays only a subordinate role. Between 16 000 and 80 000 r.p.m. the values are the same. In the region of 10 000 r.p.m. the sound level is frequently reduced, even if a few loud peaks may still occur here. The type of drilling machine, the handpiece or transmission handpiece used have no effect. Altogether, the rotary drill produces less sound transmitted to the inner ear through the body than through the air.

Bone Conduction↗