PubMed Health⌕ Search

Biomedical subjects

E Andersen

Publications and source records attributed to E Andersen.

At least 145 records · Page 8Linked to original sources
PubMed1983

Electrophysiological evidence of concurrent dorsal raphe input to caudate, septum, habenula, thalamus hippocampus, cerebellum and olfactory bulb.

Field potentials evoked by electrical stimulation of the dorsal raphe nucleus (DR) were recorded in eight forebrain structures in the rat. The areas were chosen chiefly for their anatomical connections to the DR and included the olfactory bulb (OB), caudate nucleus (CN), lateral septum (Spt), lateral habenula (Hb), parafascicularis (PF), ventral thalamus (VT), hippocampus-CA1 (Hipp), and cerebellum (CB). DR stimulation evoked an initial biphasic positive-negative wave form at similar latencies in each of the eight structures. A later positive-negative-positive wave was evoked in only six structures: CN, Spt, Hb, PF, VT, and Hipp. The amplitudes and latencies of the peaks of the later wave forms varied among structures. A depth profile recording procedure created by moving the DR stimulating electrode showed that the responses in the remote structures occurred only when the stimulating electrode was located in the DR. Bursting the DR at 20 Hz for 5-20 min caused a decrease in all components of the response. The evoked potential amplitude returned to baseline levels 5-30 min after cessation of stimulation. The results indicates that the dorsal raphe has a concurrent input to many areas of the brain receiving 5HT afferents and that DR stimulation can modulate the neuronal activity in these regions.

Animals↗
PubMed1982

Partial Turner's syndrome in four girls with Xq duplication and Xp deficiency.

Four girls with some clinical symptoms of Turner's syndrome had Xq duplication and Xp deficiency, their karyotypes being 46,X,dup(X)(p113;q11), 46,X,dup(X)(p212;q211), 46,X,dup(X)(p225;q13), and 46,X,dup(X)(p222;q213). No mosaicism was found. The major clinical findings, short stature, lack of pterygium colli, and no continuous gamete production, are compared with those in three previously published cases.

Adolescent↗
PubMed1982

Monocytotoxic antibodies after bone marrow transplantation in aplastic anemia.

Pre- and post transplant sera from 51 cases of bone marrow transplants performed for severe aplastic anemia were tested on monocytes (M) and corresponding B cells (B) from a panel of unrelated donors. One-third of the sera were cytotoxic for B and M either from different or from the same individuals, while 45% reacted only to M and appeared to recognize non-HLA M-associated antigens. No significant reaction to endothelial cells was obtained from these sera. The subsequent clinical course was not associated with any reaction pattern of pre-transplant sera. There was a significant relationship between rejection and the development of M antibodies after grafting, but since these were also found in many other patients without rejection, their occurrence has no predictive value for an individual patient.

Anemia, Aplastic↗
PubMed1982

Dorsal raphe nucleus modulates sensory evoked responses in caudate and septum.

The dorsal raphe nucleus (DR) was examined for its possible modulatory effects on sensory input to the caudate nucleus (CN) and lateral septum (Spt) in freely behaving rats. Three types of DR stimulation were tested for their effects on sensory evoked responses: (1) a single pulse of electrical stimulation of the DR prior to each sensory stimulus, (2) a 5-20 min burst of 20 Hz stimulation of the DR prior to sensory stimulation, and (3) a combination of the single pulse and the 5-20 min burst (20 Hz) stimulation of the DR prior to the sensory stimulation. Each of the three forms of DR stimulation caused a decrease in the amplitudes of the sensory-evoked responses recorded from the CN and Spt. Combination of DR stimulation caused stronger (summation) attenuation of the sensory responses. Thus, DR was shown to affect sensory input recorded in CN and Spt.

Animals↗
PubMed1982

The role of temporal factors in auditory perception of consonants and vowels. A study of different age groups.

Two series of speech identification tests were conducted in different age groups, the first test consisting of 11 synthetic speech stimuli varying in vowel length, the second test being composed of 30 natural speech stimuli varying in length of the initial consonant. Categorical perception of different phonemes was demonstrated in both experiments in all age groups. Persons more than 65 years of age showed significantly lower response percentages in both tests than did younger subjects. In the test where natural speech stimuli were used, boundaries of phoneme-category shift were dislocated in the older when compared with results of the younger subjects. Furthermore, speech discrimination was poorer in monaural than in binaural listening condition in the groups of more than 65-year-old persons with signs of age-induced sensorineural hearing loss; in this age group women showed clearly better results than men. These differences could not be demonstrated in the younger age groups.

Adolescent↗
PubMed1982

The effect of age and hearing loss on the identification of synthetic /b, d, g/-stimuli.

A series of speech identification tests using 15 synthetic consonant-vowel syllables with variations in second and third formant transitions were conducted in different age groups with normal hearing and a group of older subjects with a sensorineural hearing loss. Varying degree of categorical perception of three distinct phoneme categories /b, d, g/ was observed in all groups. Responses were depending on start frequency and gliding direction of second and third formant transitions. In the group of 60-80-year-old persons with a hearing loss response percentages were significantly lower and error frequency high. Furthermore, category shift boundaries changed as compared with the group of 20-40 years old. Results in a group of children age 8-15 years, were rather similar to those in the 20-40-year-old group. Both age and age-induced sensorineural hearing loss seemed to influence elderly people's ability to identity the synthetic speech stimuli.

Adolescent↗
PubMed1981

Macular function in typical and reticular retinoschisis.

Fifty-three patients with typical and reticular degenerative retinoschisis were evaluated. They demonstrated a corrected visual acuity of 20/20 except when some independent and unrelated ophthalmic condition was present. With a special protocol of test procedures, macular function in nine degenerative retinoschisis patients was found not significantly different from macular function in nine control patients. Macular function prognosis associated with degenerative retinoschisis is favorable, and implications for differential diagnosis are presented.

Aged↗
PubMed1981

Modification of the platelet suspension immunofluorescence test.

This study reports two modifications of the Platelet Suspension Immunofluorescence Test which make it more convenient to use for the rapid identification of platelet-specific antibodies and for screening individuals if platelet donors of a particular type are urgently required. Platelets frozen both before and after paraformaldehyde (PFA) fixation were compared with fresh PFA-fixed platelets using anti-PLA1 and anti-HLA antisera. Further, a comparison was made between the results of the test when performed in tissue culture trays or in tubes as originally described. Platelets, prefixed with PFA and then frozen appeared similar in all respects to fresh PFA-fixed platelets with no loss of antigenicity and no non-specific fluorescence. Although platelets fixed after frozen storage were also satisfactory, they were less convenient to use and lost some brilliance in staining. When the test was performed in tissue culture trays, there was no loss in sensitivity, and the volume of antiserum used was halved. However, the main advantage was the efficiency and ease with which the test could be performed, especially when handling large numbers of samples.

Antibodies↗
PubMed1981

Risk factors in multiple sclerosis: tuberculin reactivity, age at measles infection, tonsillectomy and appendectomy.

The purpose of the present study was to investigate whether risk of multiple sclerosis (MS) is associated with the occurrence of viral or bacterial diseases, with vaccinations, or with operative events during childhood. Our reference population was 198,000 persons recorded in the register of school health records from the Copenhagen council. We compared 92 MS patients contained in the register with matched controls from the register, three for each patients. Risk of MS was inversely associated with a positive tuberculin skin test at age 7 years, i.e. with exposure to tuberculosis before the age of 7, possibly also with the occurrence of measles infection before age 7 (not statistically significant). Disease risk was not significantly related to other viral or bacterial infections of childhood, nor to routine vaccinations, tonsillectomy, adenoidectomy or appendectomy. Our findings suggest a difference between MS patients and controls with respect to environment before school age, the former being less exposed to air-borne infections.

Adenoidectomy↗
PubMed1980

Risk of multiple sclerosis inversely associated with birth order position.

The aim of this study was to ascertain whether there is an association between risk of multiple sclerosis (MS) and birth order position. Our reference population was 198,000 persons born in the period 1930-50 and recorded in the register of school health records from the school health service of the Copenhagen council. We compared 46 persons from the register who had developed MS with matched controls from the register, three for each case. An inverse association between risk of MS and birth order position was found. Early birth orders tend to delay exposure to an infectous agent from early childhood to a later age. Therefore, our finding supports the hypothesis that MS is causally related to an infection that is inapparent when it occurs in early childhood, while infection later in life may result in severe disease

Birth Order↗
PubMed1980

A case of cold haemoglobinuria with later sarcoidosis. Treatment with plasmapheresis and immunosuppressiva.

A case of severe but transient haemolytic disease occurring after a febrile episode is described. The thermal amplitude of the haemolysin was high during the acute phase, since the autoantibody fixed complement at 31 degrees C. After 4 months complement fixation could exclusively be demonstrated at 4 degrees C. The patient was treated in a room heated to 30-32 degrees C. The treatment consisted of prednisone and azathioprine and during the acute phase plasmapheresis was attempted in order to reduce the antibody concentration. However, the haemolysis decreased when the thermal amplitude of the antibody diminished. 1 year after termination of therapy, she developed sarcoidosis.

Adult↗