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Biomedical subjects

K Andersen

Publications and source records attributed to K Andersen.

At least 19 recordsLinked to original sources
PubMed1992

Selective, centrally acting serotonin 5-HT2 antagonists. 1. 2- and 6-substituted 1-phenyl-3-(4-piperidinyl)-1H-indoles.

A series of 1-[2-[4-(1H-indol-3-yl)-1-piperidinyl]ethyl]-2-imidazolidinones has been synthesized. The 1-position of the indole is substituted with phenyl groups and in the 2- or 6-positions are additional substituents. An analogous series with the imidazolidinone ring opened to corresponding urea derivatives was also prepared. High potency and selectivity for 5-HT2 receptors (as compared with D2 and alpha 1 receptor affinities) were obtained with medium-large substituents such as 6-chloro, 6-methyl, and 6-trifluoromethyl or a 2-methyl substituent. Larger 6-substituents such as isopropyl considerably reduced activity, while the smaller 6-fluoro substituent afforded unselective compounds. Selective 5-HT2 antagonists were found by combining 6-substitution with both unsubstituted 1-phenyl and substituted 1-phenyl groups (2-F, 4-F, 4-Cl). However, 3-substitution of the phenyl group markedly reduced 5-HT2 receptor affinity, especially with a 3-trifluoromethyl substituent. Introduction of a 3-(2-propyl) substituent in the imidazolidinone ring reduced binding to alpha 1 adrenoceptors with a factor of 3-8. Practically no influence on 5-HT2 and D2 receptor affinities were found by the presence of this substituent compared to the 3-unsubstituted derivatives. Compounds with potent receptor binding also potently inhibited the quipazine-induced head twitch syndrome in rats. The compounds were equally active after oral and subcutaneous administration and they had a long duration of action (> 24 h). Especially urea derivatives were found to be considerably more potent at 24 h than at 2 h after subcutaneous administration. Some of the compounds potently inhibited isolation-induced aggression in mice, an effect which, however, did not correlate to 5-HT2 receptor-mediated activities. On the basis of these structure-activity studies 1-[2-[4-[6-chloro-1-(4-fluorophenyl)-1H-indol-3-yl]-1- piperidinyl]ethyl]-3-(2-propyl)-2-imidazolidinone (Lu 26-042, compound 4c) was selected for further pharmacological and toxicological investigations.

Animals↗
PubMed1992

Selective, centrally acting serotonin 5-HT2 antagonists. 2. Substituted 3-(4-fluorophenyl)-1H-indoles.

A series of 3-(4-fluorophenyl)-1H-indoles substituted in the 1-position with 4-piperidinyl, 1,2,3,6-tetrahydro-4-pyridinyl, and 4-piperazinyl was synthesized. By variation of the substituents in the benzene part of the indole nucleus in 1-[2-[4-[3-4-fluorophenyl)-1H-indol-1-yl]-1-piperidinyl]-ethyl]-2- imidazolidinones, the highest 5-HT2 receptor affinity and selectivity with respect to dopamine D2 receptors and alpha 1 adrenoceptors were obtained by 5-methyl substitution. Different substituents were introduced in the 1-position of the piperidine ring in the 5-methyl-substituted derivative. Thus replacement of the 2-(2-imidazolidinon-1-yl)ethyl side chain with a 2-(1,3-dimethyl-1-ureido)ethyl or methyl substituent resulted in unchanged affinity and selectivity for 5-HT2 receptors. Replacement with a 2-[3-(2-propyl)-2-imidazolidinon-1-yl]ethyl side chain reduced binding to alpha 1 adrenoceptors with a factor of four, while affinities for 5-HT2 and D2 receptors were retained, compared to the 3-unsubstituted imidazolidinone. Indoles substituted in the 1-position with 4-piperazinyl had generally weaker affinity for both 5-HT2 and D2 receptors compared to corresponding 4-piperidinyl- and 1,2,3,6-tetrahydro-4-pyridinyl-substituted indoles. Introduction of a methyl group in the 2-position of the 5-methyl-substituted indole resulted in further increase of selectivity for the 5-HT2 receptor. Compounds with potent receptor binding also potently inhibited the quipazine-induced head twitch syndrome in rats. The compounds were equally active after oral and subcutaneous administration and showed a long duration of action (> 24 h). In general, the derivatives were found to be considerably more potent at 24 h than at 2 h after the administration. The compounds within this series were prepared as analogues of the previously described 1-(4-fluorophenyl)-3-(4-piperidyl)-1H-indoles by interchange of the C-3 carbon atom and the nitrogen atom in the indole nucleus. The pharmacological results indicate that this isosteric replacement results in higher selectivity for 5-HT2 receptors compared to the former series. The 1-[2-[4-[2,5-dimethyl-3-(4-fluorophenyl)-1H-indol-1-yl]-1- piperidinyl]ethyl]-2-imidazolidinone has high affinity for 5-HT2 receptors (IC50 = 3.4 nM) and extremely low affinity for both dopamine D2 receptors (IC50 = 6900 nM) and alpha 1 adrenoceptors (IC50 = 2300 nM).

Animals↗
PubMed1992

[Nerve compression symptoms after a long bicycle ride--the Great Test of Strength].

Every year a bicycle-race over 540 km is arranged from Trondheim to Oslo, attracting approximately 5,000 amateur participants. It is well known that nerve compression syndromes may occur in connection with cycling, affecting in particular the ulnar nerve in the Guyon's canal and the pudendal nerve. A questionnaire study was carried out to evaluate the frequency of such complaints (N = 260). 32 (20%) of the 169 cyclists who completed the questionnaire reported numbness in the innervation area for the superficial branch of the ulnar nerve and 11% in the area of the median nerve. Approximately 15% reported paresis in the hand. The problem seemed to be transient. There was a slight tendency towards more symptoms among the most experienced cyclists, indicating that chronic compression may be more serious than the compression related to a single long tour.

Bicycling↗
PubMed1992

[Septic sacroiliitis].

Septic sacroiliitis (SSI) is a rare form of pyogenic arthritis, which unrecognized or inadequately treated may cause longterm morbidity and eventually lasting disability. SSI is most frequently diagnosed among young adults, especially in drug abusers. Based on a literature survey three cases of SSI are presented, each representing characteristic aspects of SSI. The condition should be considered in cases of acute or subacute onset of pain in the gluteal region, hip or low back accompanied by fever. Laboratory findings are variable and non-specific. Definite bacteriologic diagnosis is only achieved in about 75% of the cases. In almost all of the cases, Tc-99m-MDP bone scintigraphy will in almost all the cases show increased uptake in the affected joint within one week after onset of symptoms. Generally antibiotic treatment leads to complete recovery.

Adult↗
PubMed1992

Detection of rhinorrhoea by cisternography in combination with single photon emission tomography, following lumbar injection of iodine-123-labelled albumin.

Eight patients were examined. Seven had verified rhinorrhoea and six had had one or more episodes of pneumococcal meningitis. In four of the patients a fistula could not be visualized by computed tomography. All eight patients had injections of iodine-123-labelled albumin by lumbar puncture. Tomoscintigraphy (SPET) was performed 3, 6 and 8-9 h after injection. After 6-8 h we were able to demonstrate a fistula in seven of the patients with verified rhinorrhoea and the findings were confirmed by a subsequent operation. In one of the patients we were not able to visualize any leak of cerebrospinal fluid into the nasal cavity. This patient was not operated upon and we were not able to verify the findings in this patient. The operated patients all did well after the operation with no relapse of meningitis. In conclusion, SPECT-cisternography after intralumbar injection of iodine-123-labelled albumin is a valuable diagnostic tool for the detection of small fistulae in patients with rhinorrhea.

Adult↗
PubMed1992

Mediastinal germ cell tumour associated with Klinefelter syndrome. A report of case and review of the literature.

A 14-year-old boy with Klinefelter syndrome (KS) and a large mediastinal tumour is presented. Human chorionic gonadotropin and oestradiol were markedly increased. An attempt at radical resection was performed. Histological examination revealed a malignant germ cell tumour of mixed histologic pattern composed of choriocarcinoma and components of mature teratoma. Four courses of cisplatin, bleomycin, and etoposide were given. The patient is without any evidence of tumour recurrence 20 months after diagnosis. A review of the literature revealed another 40 cases of primary mediastinal germ cell tumour (PMGCT) associated with KS. Compiled data from larger series demonstrate that at least 8% of male patients with PMGCT have KS, 50 times the expected frequency. In contrast to PMGCT in patients without KS, all tumours were of nonseminomatous histology, and the average age was considerably lower, Tumours in prepubertal boys were associated with precocious puberty.

Adolescent↗
PubMed1992

The importance of sculpin (Myoxocephalus scorpius) as intermediate host and transmitter of the sealworm Pseudoterranova decipiens.

A total of 186 sculpins (Myoxocephalus scorpius) were caught at Vega, Nordland, Norway, and examined for sealworm larvae (Pseudoterranova decipiens). Over 80% of the fish were infected. Very high infections were found with a maximum of nearly 300 larvae in one sculpin. Infections of this magnitude have so far not been reported from sculpins or any other fish species of this size. The importance of the sculpin in the life cycle and in the transmission of P. decipiens to seals or other fish species is briefly discussed.

Animals↗
PubMed1992

Congenital sideroblastic anaemia with intrauterine symptoms and early lethal outcome.

Sideroblastic anaemia is a rare disease, which most often presents in early childhood. A case of ringed sideroblastic anaemia with onset in early foetal life in a female infant, resulting in severe intrauterine symptoms, is reported. Six weeks after birth a bone marrow examination revealed a large amount of typical ringed sideroblasts, thus establishing the diagnosis. In spite of repeated blood transfusions, the haemoglobin content gradually decreased. The condition was refractory to pyridoxal phosphate treatment and continued to deteriorate with lethal outcome four months after birth.

Anemia↗
PubMed1991

[Spirometry].

Explore the source record for details and available documents.

Humans↗
PubMed1991

Rolando's fracture.

The relationship between methods of treatment, quality of reduction and the occurrence of late disability and osteo-arthritic changes was studied in 17 Rolando's fractures. Three were undisplaced, 14 were displaced: of these excellent reduction was achieved in five of 11 treated by open reduction and in none of the three treated by percutaneous K wire fixation. After a median interval of 5.8 years, six of 16 reviewed patients had minor symptoms, while nine had no symptoms. Radiographic examination of 11 patients showed signs of osteoarthritis in six. We did not establish a relationship between the quality of reduction and the occurrence of late symptoms and osteoarthritis.

Adult↗
PubMed1991

Location of centres of resistance for maxillary anterior teeth measured on human autopsy material.

The location of the centre of resistance (CR) of various consolidated units of maxillary anterior teeth was determined in this study using human autopsy material. The units studied consisted of two central incisors, four incisors, and six anterior teeth. When horizontal forces were applied the CR for the two- and six-tooth units was located approximately 6.5 mm apical to the bracket position. For the four-tooth unit, CR was placed slightly more occlusally, the distance being 5.0 mm. Applying vertical forces CR was located about 13.0 mm posterior to the bracket position for the two- and four-tooth unit. The incorporation of the canines into the incisor segment resulted in a distal shift of CR of 6 mm. CR for the six anterior teeth was, thus, located on a line 3 mm behind the distal surface of the canines. Increasing force levels had little effect on the location of CR for a given unit.

Adult↗
PubMed1991

Dietary supplementation with omega-3-polyunsaturated fatty acids decreases mononuclear cell proliferation and interleukin-1 beta content but not monokine secretion in healthy and insulin-dependent diabetic individuals.

The effects of dietary supplementation with omega-3-polyunsaturated fatty acids (omega-3-PUFA) on the proliferative response of PBMC and on the secretion of monokines and arachidonic acid metabolites from PBMC and monocytes (Mo) from healthy subjects and patients with recent-onset insulin-dependent diabetes mellitus (IDDM) were examined. Three groups of eight to nine healthy individuals were randomized to either 2.0 g/day or 4.0 g/day of omega-3-PUFA devoid of vitamins A and D, or an isocaloric amount of placebo. Furthermore, eight patients with recent-onset IDDM received 4.0 g/day of omega-3-PUFA. IL-1 beta production and TNF-alpha secretion was determined before and after 7 weeks of treatment, and 10 weeks after withdrawal of treatment. Significant increases in platelet and PBMC membrane eicosapentaenoic acid was found in omega-3-PUFA-treated individuals. omega-3-PUFA treatment significantly reduced the content of IL-1 beta in lysates of PBMC, but did not affect PBMC or Mo secretion of IL-1 beta, TNF-alpha or prostaglandin E2 (PGE2) or PBMC leukotriene B4 (LTB4) secretion in healthy subjects or in IDDM patients. A significant inhibition of the PHA-stimulated, but not the spontaneous or PPD-stimulated, proliferative response of PBMC was observed in healthy and diabetic subjects treated with omega-3-PUFA. No correlation was found between PHA-stimulated PBMC proliferation and PBMC secretion of TNF-alpha and IL-1 beta. There were no significant differences in the spontaneous or the PPD- or PHA-stimulated proliferative responses of PBMC between diabetic and healthy individuals at entry. We conclude that although dietary supplementation with 4.0 g/day of omega-3-PUFA inhibits the proliferation of PBMC and reduces IL-1 beta immunoreactivity in PBMC and Mo, it does not alter monokine, PGE2 or LTB4, secretion in healthy or IDDM subjects.

Adult↗
PubMed1991

Inter- and intrasexual dimorphisms in the vocal control system of a teleost fish: motor axon number and size.

In one species of vocalizing fish, the plainfin midshipman (Porichthys notatus), large, nest-guarding males ('type I') use striated muscles to produce acoustic communication signals that include short duration (less than 1 s) 'burps' important in agonistic encounters and long duration (in the order of minutes) 'hums' which function in attracting females to nest sites during the breeding season. Females, and a second group of smaller reproductively active males ('type II') that 'sneak' spawn, do not generate hums, although they produce burps. Differences in vocal behavior are paralled by a relative increase of 6-fold in the sonic muscle of type I males. Inter- and intrasexual dimorphisms in sonic muscle mass were matched by those in the cross-sectional area of sonic motor axons, but not by those in number of axons. Thus, axon size was 2- to 3-fold larger in type I males than in females, type II males, or juveniles, none of which differed significantly from each other. Axon number was similar between type I males and females of a similar body size, despite the extreme dimorphism in sonic muscle mass. Axon number, however, was slightly greater (0.1-fold) in type I males and females compared to the smaller-sized juveniles and type II males. Type II males, in comparison to the non-reproductive juvenile males, have gonads that are about 20-fold larger and produce mature sperm. Nevertheless, the two groups resemble each other in body and swimbladder size, as well as sonic motor axon size and number. This suggests that type II males represent a subset of juvenile males that undergo precocious gonadal hypertrophy and spermiogenesis, but retain juvenile-like nongonadal traits. The results are discussed within the context of the development of vertebrate motor systems as well as the evolution of alternative reproductive tactics among teleost fishes.

Air Sacs↗