Search PubMed⌕ Search

Biomedical subjects

S Nielsen

Publications and source records attributed to S Nielsen.

At least 307 records · Page 17Linked to original sources
PubMed1988

Lesion of the ligamentum bifurcatum in ankle sprain.

In a consecutive study of 106 patients with a history of ankle sprain, 40.5% showed clinical signs of damage to the ligamentum bifurcatum of the midfoot. A significantly larger percentage of these patients complained of maximum tenderness localized to the instep compared with the patients without signs of damage to the ligamentum bifurcatum (P less than 0.001). Radiologic examination revealed 20 lesions related to damage to the ligamentum bifurcatum: laxity in the transverse tarsal joint, 12; avulsion from the anterior process of the calcaneus, 5; avulsion from the cuboid, 2; avulsion from the navicular, 1. The clinical importance of these findings is debatable. Previous investigations have revealed hypermobile ankles in patients with laxity in the transverse tarsal joint, as well as long convalescence time and risk of nonunion in patients with fractures of the anterior process of the calcaneus. It is therefore recommended that patients with a history of ankle sprain be evaluated concerning damage to the ligamentum bifurcatum of the midfoot.

Adolescent↗
PubMed1988

Afternoon plasma cortisol in relation to depression. A replication study.

In 37 consecutive depressed inpatients afternoon plasma cortisol (1500-1520 h) was measured in 3 ways: 1) spontaneously; 2) 2 h after oral administration of 60 mg oxazepam; and 3) 16 h after oral administration of 2 mg dexamethasone. Both oxazepam and dexamethasone caused a significant suppression of cortisol secretion. Spontaneous and suppressed cortisol levels correlated significantly to stress/distress items on the Hamilton Rating Scale for Depression (sum of items 8, 9, 10 and 12), whereas no correlations to age, or type of depression were found. In an earlier similar study of 35 patients both spontaneous and suppressed cortisol levels correlated significantly with age, type and severity of depression as well as with the stress/distress items. Those patients were older, more depressed (HRSD-17) and had higher stress/distress scores compared with the present sample of 37 patients. The consistent finding of a correlation with the stress/distress items suggest that this factor is important in relation to the hypersecretion of cortisol during depression and this may explain the limited diagnostic power of spontaneous and suppressed cortisol levels.

Adult↗
PubMed1988

Influence of flow rate and perfused load on insulin absorption in isolated proximal tubules.

The effect of flow rate and perfused load on insulin absorption was studied in isolated proximal rabbit tubules. In one series of experiments tubules were perfused for 30 min with 125I-[A14]insulin at 3.6 ng/ml and at flow rates varying between 2.2 and 43.3 nl/min, thus varying both flow rate and the perfused load. In a second series of experiments the tubules were exposed to increasing loads of insulin at a fixed flow rate of 15 nl/min. In a third series of experiments two groups of tubules were exposed to identical perfused loads at two different flow rates. The results showed that absorption is linearly correlated with the perfused load in the ranges of flow rates and concentrations examined. The perfused load determined the magnitude by which the insulin was reabsorbed, whereas the flow rate determined the efficiency (fractional absorption) by which the protein was reabsorbed. At flow rates less than 5 nl/min the fractional absorption was greater than 65%, and at flow rates greater than 30 nl/min fractional absorption was less than 40%. Thus, there is an inverse relationship between flow rate and fractional absorption. The described effects of changes in flow rate and perfused load are suggested to be caused by concomitant changes in the mean luminal concentration.

Absorption↗
PubMed1987

Radiologic findings in lesions of the ligamentum bifurcatum of the midfoot.

In a consecutive study of 106 patients presenting with a history of ankle sprain, 40.5% showed clinical signs of damage to the ligamentum bifurcatum. Eighteen of these patients showed 20 radiologic signs related to a lesion of this ligament; these signs included avulsions from the points of insertion and laxity in the lateral part of the transverse tarsal joint. The supplementary radiographs revealing these signs are demonstrated, and a more differentiated radiologic handling of the patient with ankle sprain is suggested.

Adolescent↗
PubMed1987

Levels of synthesis of primate-specific nuclear proteins differ between growth-arrested and proliferating cells.

A monoclonal antibody that reacts specifically with the proliferation-sensitive nuclear proteins, isoelectric focusing (IEF) 8Z30 and 8Z31 (molecular weight (MW), 76,000 charge variants, HeLa protein catalogue number) has been characterized. As determined by indirect immunofluorescence, the antibody stains the nucleolus and nucleoplasm of interphase-cultured cells of primate origin, but does not react with cells of other species. Proteins having similar MWs and isoelectric points as the human or monkey (primates) proteins were not observed in cultured cells of the following species: aves, bat, dog, dolphin, goat, hamster, mink, mouse, pisces, potoroo, rabbit and rat. Quantitative two-dimensional (2D) gel electrophoretic analysis of [35S]methionine-labeled proteins synthesized by normal (quiescent, proliferating) and SV40-transformed human MRC-5 fibroblasts revealed significant differences in the levels of synthesis of both IEF 8Z30 and 8Z31. In quiescent cells the main labelled product corresponded to IEF 8Z31 (ratio IEF 8Z31/8Z30, 2.3), while in the transformed cells the major product was IEF 8Z30 (ratio, 0.62). Normal proliferating fibroblasts exhibited similar levels of both proteins (ratio, 1.21). Combined levels of synthesis of both proteins were 1.50 and 1.20 times as high in the transformed cells as in the quiescent and proliferating cells, respectively. Similar results were observed in other pairs of normal and transformed human cells, such as WI38/WI38 SV40 and amnion/AMA. Modulation of the levels of synthesis of these proteins may play a role in cell proliferation.

Animals↗
PubMed1987

Cytomegalovirus encephalitis in patients with acquired immunodeficiency syndrome: an autopsy study of 30 cases and a review of the literature.

The pathology of cytomegalovirus (CMV) encephalitis was studied at autopsy in thirty patients with acquired immunodeficiency syndrome. Lesions could be segregated into five major categories: microglial nodules, isolated inclusion-bearing cells, focal parenchymal necrosis, necrotizing ventriculo-encephalitis, and necrotizing radiculo-myelitis. Microglial nodules and CMV inclusions were present in all brains. Microglial nodules were found with variable frequency and had greatest density in subcortical grey matter. Only a small percentage (average, 6.5 per cent) contained CMV inclusion-bearing cells. Isolated inclusion-bearing cells unaccompanied by microglial nodules or inflammatory infiltrates were seen in half the patients. CMV inclusions were identified in capillary endothelia, astrocytes, and neurons. Focal CMV necrosis, ventriculo-encephalitis, and radiculo-myelitis were less frequent. The presence of CMV inclusions in capillary endothelia suggests a vascular portal of entry for the virus into the central nervous system. The diffuse ependymal and/or subpial distribution of CMV in several patients suggests additional dissemination via the cerebrospinal fluid. Isolated inclusion-bearing cells may reflect the relative nonpermissiveness of surrounding central nervous system parenchyma for CMV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Characterization of a monoclonal antibody (BG3C8) that reacts with basal cells of stratified epithelia.

Monoclonal antibodies were produced against a suspension of formaldehyde fixed human epidermal cells. The supernatant fluid of one clone (BG3C8) yielded a bright immunofluorescent staining of basal cells both in cryostat sections of human split skin and in preparations of purified basal cells. As determined by one- and two-dimensional gel immunoblotting of epidermal basal cell proteins the antibody recognized a minor basic polypeptide of 55,000 apparent molecular weight that was not present in extracts of cultured cell lines of epithelial, fibroblast and lymphoid origin. The distribution of the 55,000 molecular weight protein in normal human tissue was determined by immunohistological staining of cryostat tissue sections that included: central nervous, endocrine, female and male reproductive, alimentary, lymphatic-haemopoietic, respiratory and urinary systems, skin and its appendages, mesenchymal tissue (bone, cartilage, muscle, connective tissue, blood vessels, nerves and synovia) as well as placenta and umbilical cord. The results showed a restricted distribution of this antigen which was found only in basal cells of most stratified or pseudostratified epithelia and in myoepithelial cells. This antibody may be useful in the study of normal and pathological differentiation in various epithelial disorders.

Animals↗
PubMed1987

Anorexia nervosa/bulimia in diabetes mellitus. A review and a presentation of five cases.

Review of recent literature with emphasis on growth, development and epidemiology of eating disorders and diabetes reveals many common features of the conditions. Thus we hypothesize more concurrence than would occur by chance alone. At present epidemiological evidence is inconclusive, but prevalence of eating disorder seems increased in insulin dependent diabetes mellitus (IDDM). Over a period of 25 years five cases (all female) of diabetes were found in a consecutive series of 242 patients with eating disorders treated at the Child Psychiatric and Psychiatric Clinics at Rigshospitalet, Copenhagen, Denmark. This is a six-fold increase in prevalence of IDDM. IDDM preceded eating disorder (anorexia nervosa (AN)/bulimia(B)) in four of the five cases, and contributed significantly to the psychopathology found: the more, the earlier the age at onset of IDDM. Treatment proved difficult and the outcome seems serious. At latest contact four cases had manifest eating disorders and three of these had unstable and complicated IDDM as well. The patients' adaptation to IDDM seems crucial for the outcome.

Adaptation, Psychological↗
PubMed1987

Luminal and basolateral uptake of insulin in isolated, perfused, proximal tubules.

The present study was performed to quantitate and compare the luminal and the peritubular uptake of 125I-labeled insulin in isolated, perfused, proximal tubules from rabbit kidneys. 125I-insulin was added in physiological concentrations of 3.0-7.0 ng/ml or 59.0-89.5 ng/ml (high insulin concentrations) to either the perfusate or the bath fluid for 30 min. The luminal uptake in 30 min averaged 0.76 pg/mm at physiological concentrations and 18.0 pg/mm at high insulin concentrations. About 15-41% of the absorbed insulin was digested and less than 5% was transported from the lumen to the peritubular space as intact insulin. The peritubular binding/uptake of 125I-insulin at physiological and high concentrations in the bath was 0.136 and 0.318 pg, respectively. Addition of excess unlabeled insulin (10(-5) M) to the bath produced significant inhibition of binding (53.7%) at 7.0 ng/ml, but no inhibition at 89.5 ng/ml labeled insulin in the bath. This indicates that insulin is bound/absorbed at the basolateral membranes both by a saturable specific mechanism and a nonspecific, nonsaturable mechanism. The basolateral absorption constituted 15.2 and 1.8% of the total tubular extraction of insulin at physiological and high insulin concentrations, respectively. Electron microscope autoradiography showed that, after luminal as well as basolateral endocytosis, insulin was exclusively accumulated in endocytic vacuoles and lysosomes.

Animals↗
PubMed1987

Lateral talocalcaneal instability following section of the calcaneofibular ligament: a kinesiologic study.

In the evaluation of the role of the calcaneofibular ligament in stabilizing the talocalcaneal joint, an experimental set-up was prepared. In 10 osteoligamentous specimens, the talocalcaneal motion was measured under a constant well defined moment by using a specially constructed apparatus. By using a moment of 1.5 Nm, increment in adduction in the talocalcaneal joint after section of the calcaneofibular ligament was found between 3.1 degrees and 4.6 degrees, still increasing with dorsiflexion. This increment, shown to constitute 61 to 77% of the total increment in adduction in the hindfoot after section of the calcaneofibular ligament, was found to increase gradually with dorsiflexion. The study has shown the calcaneofibular ligament as an important structure in stabilizing the talocalcaneal joint. Increment in adduction in the hindfoot after section of the calcaneofibular ligament was shown primarily to take place in the talocalcaneal joint.

Cadaver↗
PubMed1987

Effect of the calcaneofibular ligament on hindfoot rotation in amputation specimens.

A kinesiologic study of the range of rotation in the hindfoot after cutting of the calcaneofibular ligament was performed in amputation specimens. Cutting of the calcaneofibular ligament results in a significant increment in the external rotation of the tibial-talocalcaneal joint complex and the talocalcaneal joint, maximum 5.4 degrees and 2.9 degrees, respectively. The total range of rotation in the tibial-talocalcaneal joint complex and the talocalcaneal joint increased 32 and 20 per cent, respectively. The calcaneofibular ligament is an important structure in the rotatory stabilization of the hindfoot.

Amputation, Surgical↗
PubMed1987

Kinesiology of the knee joint. An experimental investigation of the ligamentous and capsular restraints preventing knee instability.

The purpose of this study was to elucidate the function of the ligamentous and posterior capsular structures of the knee joint and the types of instability that may be caused by lesions to these structures. Despite the use of complicated technical appliances and the defined, uniform conditions, the investigators in measuring the mobility in the knee joint have usually arrived at divergent results. Often, the manner of measuring the various movements has not been mentioned, or the moment or force applied to the knee joint were not well-defined, or else the instability was recorded at only a few positions during the extension-flexion movement of the knee. A measuring apparatus was devised which allows continuous registration, accurately, and in a reproducible manner, of the valgus-varus, axial rotatory, and translatory instability in the extension-flexion movement of the knee during application of a well-defined, constant moment or force to the knee joint. A lever, fitted with strain gauges and connected to three potentiometers, was fixed to the tibia. The lever was moved manually in a way so that during a "circumduction" of the lever, the moment was constant in the valgus, varus, internal or external axial rotation direction. Likewise, the anteriorly or posteriorly directed force was constant. Anterior-posterior tibial displacement was measured by two sliding potentiometers. By means of a computer the resulting movement could be plotted in the form of mobility patterns. Patterns were plotted partly with intact ligaments and partly after isolated and various combinations of transection of the collateral ligaments, the posterior capsule, the cruciate ligaments, and the popliteal tendon. A total of 115 preparations were investigated in this manner.

Biomechanical Phenomena↗