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Biomedical subjects

J Jakobsen

Publications and source records attributed to J Jakobsen.

At least 91 records · Page 5Linked to original sources
PubMed1991

Tooth and bone development in a Danish medieval mandible with unilateral absence of the mandibular canal.

A Danish anthropological collection of medieval human skeletons excavated in 1986 involves a mandible (No. 212) from an adult female born without the lower alveolar nerve and mandibular canal. It is believed that the defect has resulted in lack of tooth development on the affected side and that the mylohyoid nerve has partially compensated for this defect by development of teeth in localized areas. The defective mandibular dentition has caused a compensatory development of the alveolar process in the maxilla. The missing occlusal support has altered muscular traction on the mandible. This has caused an alteration in mandibular shape. Whether the asymmetric development of the mandible is caused by muscular dysfunction, by failure in angular growth apposition, or by a combination of these factors is discussed. The case presents valuable data in the ongoing discussion about the interaction between nerve tissue and tooth formation and about the interaction between occlusion, jaw morphology, and muscular traction. The study shows how archeological material in an interdisciplinary cooperation between archeological, embryological and orthodontic research can contribute to the clarification of current biological problems.

Alveolar Process↗
PubMed1991

Differences in need for orthodontic treatment between Native Americans and the general population based on DAI scores.

Clinical impressions by Indian Health Service (IHS) dentists of a greater frequency of severe dental malrelations among Native Americans than in the general US population have never been objectively confirmed. This study uses the DAI as the standard to determine whether there is a greater prevalence of severe malocclusions among Native Americans. Four hundred eighty-five Native American students in grades 7-12 from two remote sites--Pine Ridge, SD, and Many Farms, AZ--and one nonremote site--Lapwai, ID--were scored for the DAI. The mean scores from each reservation, as well as the mean score from the three reservations combined, were significantly higher, indicating poorer aesthetics, than the mean DAI score from a large sample of the general US population. These data confirm the clinical impressions of IHS dentists that Native Americans residing on reservations have significantly poorer dental aesthetics than the aesthetics found in the general US population; therefore, Native Americans have greater needs for orthodontic treatment.

Adolescent↗
PubMed1991

[Identification of victims after a fire on the ferry "Scandinavian Star"].

Cooperation between Scandinavian Victim Identification Commissions was tested thoroughly after the ship disaster at Easter 1990. The fire claimed 158 victims all killed by poisonous smoke from a fast spreading fire, which went on for 36 hours. Many of the bodies were found incinerated in burnt-out cabins. More than 100 specialists were at work for 17 days before all missing persons were identified. The whole operation was led by the Norwegian authorities in Oslo. They decided that a search for human remains should be attempted in the destroyed part of the ship by help of police technicians, forensic pathologists and forensic dentists. The placing of forensic and dental expertise at the site of the disaster made it possible to identify all victims of the fire. Eighteen forensic trained dentists supported the work: thirteen from Norway, four from Denmark and one from Iceland. Two of the Danish dentists were placed at police headquarters in Copenhagen preparing the antemortem data from the Danish passengers on the ship.

Denmark↗
PubMed1990

Adaptability of two amalgams to finished cavity walls in Class II cavity preparations.

Adaptability of two amalgams--the dispersed-phase Dispersalloy and the spherical-particle-type Sybralloy--to cavity walls in a Class II cavity preparation was investigated. Four techniques for finishing cavity walls were compared, as was the adaptability of alloys at different occluso-gingival levels. The issues were examined by direct measurement of microleakage between cavity wall and the amalgam without the use of cavity varnish. There was no statistically significant difference in the adaptability of the two amalgams directly to the cavity walls, except those finished by a sharp hand instrument (hatchet) and restored with Dispersalloy. This combination demonstrated the best overall adaptability of amalgam to cavity walls. Sybralloy demonstrated best adaptability to walls finished with sandpaper discs. Although not significant, the gingival 1/3 of the Class II cavity preparation had more microleakage than the middle 1/3 or the occlusal 1/3, suggesting greater potential for recurrent decay. Overall dispersalloy demonstrated significantly better adaptability than Sybralloy.

Dental Alloys↗
PubMed1990

Myelopathy and HIV infection.

The clinical significance of myelopathy associated with HIV infection is poorly understood. Recently, a prospective electrophysiological follow-up study of spinal-evoked potentials in HIV-seropositive men without AIDS revealed a 32% prolongation of the latency from the gluteal crease to the 12th thoracic vertebra (T12) following tibial nerve stimulation at the ankle performed after an interval of 2 years. In AIDS patients this transmission delay did not increase further. Instead, the latency prolongation took place proximal to T12. We assume that myelopathy is an integral part of HIV infection that it is asymptomatic in the early disease phase, spreads from the lumbar part the spinal cord in a rostral direction and leads to the development of leg weakness and ataxia during the later stages of the disease.

Acquired Immunodeficiency Syndrome↗
PubMed1990

The acute effect of dilevalol on cerebral blood flow and oxygen consumption in normotensive humans.

The antihypertensive agent dilevalol, a stereoisomer of labetalol, causes vasodilatation by combined beta-adrenergic blockade and direct beta 2-receptor agonism. The acute effect of a single oral dose of 400 mg dilevalol on cerebral blood flow (CBF), and its response to induced changes in arterial carbon dioxide tension (PaCO2), and the cerebral metabolic rate of oxygen (CMRO2) were studied after 1, 2, and 4 h in eight normotensive volunteers. Serum dilevalol 2 h after oral intake ranged between 22 and 49 ng/ml. Mean arterial blood pressure was reduced from 93 +/- 8 to 86 +/- 8 mm Hg (p less than 0.01). An analysis of variance of the successive differences of CBF during the study showed that dilevalol altered CBF significantly. After 1 h CBF had decreased by 4.4% (p less than 0.05), whereas the 2 and 4 h values were similar to the pretreatment level. CMRO2 showed a tendency for reduction (p = 0.086). The CBF response to changes in PaCO2 remained unchanged. It is concluded that a single dose of dilevalol induces a slight and short-lasting decrease in CBF, probably due to a direct effect on brain metabolism.

Administration, Oral↗
PubMed1990

Improved energy kinetics following high protein diet in McArdle's syndrome. A 31P magnetic resonance spectroscopy study.

A patient with McArdle's syndrome was examined using bicycle ergometry and 31P NMR spectroscopy during exercise. The patients working capacity was approximately half the expected capacity of controls. Muscle energy kinetics improved significantly during intravenous glucose infusion and after 6 weeks of high protein diet. During intravenous infusion of amino acids, no changes in working capacity could be detected. No decrease was seen in intracellular muscle pH during aerobic exercise. A significant decrease in muscle pH during aerobic exercise was detected in all controls.

Adult↗
PubMed1990

Pupillary function in multiple sclerosis.

Eighteen MS patients with visual acuity of 20/30 or better and without recent visual complaints, and 14 age- and sex-matched controls were studied by TV pupillography. The response amplitude and the maximum rate of pupillary constriction or dilation of the light, dark, accommodation and ciliospinal reflexes were unchanged. The latency of the pupillary light response (PLR), however, was prolonged and closely related to walking performance (R = 0.76; p less than 0.001). No relationship was established between PLR latency and previous history of optic neuritis or latency of the VEP. It is concluded that MS patients with preserved visual acuity have only discrete autonomic pupillary disturbances and that the PLR delay is related to disease progression.

Adult↗
PubMed1990

Caries: a problem in an overdenture population.

A series of 254 patients who had their overdentures constructed at a University clinic from 1973 to 1985 were followed longitudinally. This paper reports on the caries experience in the abutment teeth of these patients. The mean age of the patients at the time of insertion of the dentures was 58.6 yr. The overall rate for new caries was 6.5% of the abutment teeth per year. The highest rate for the maxilla was 15.4%, which occurred during the 5th yr, and in the mandible it was 11.0%, which occurred in the 4th yr. A regression model was developed to profile individuals susceptible to caries. The Logistic Regression model identified a list of predictor variables which included frequency of brushing, use of home fluoride, and disease and drug effect. However, discriminant function analysis showed that although specificity was very high (98.5%), sensitivity was very low (7.9%). Therefore, this model was unable to predict persons who would be at high risk for caries.

Adult↗
PubMed1990

Symptomatic polyneuropathy in human immunodeficiency virus antibody seropositive men with and without immune deficiency: a comparative electrophysiological study.

Symptomatic polyneuropathy in human immunodeficiency virus (HIV) infection was studied in ten men with acquired immunodeficiency syndrome (AIDS) and in ten men without the immune deficiency. In both groups of patients electrophysiological signs of polyneuropathy of the axonal type were present in the sural, median and peroneal nerves. The AIDS patients had a greater reduction of the mean (SD) sural nerve action potential, 3.1 (2.7) microV, than in patients without AIDS, 10.2 (6.1) microV (p less than 0.01) and greater slowing of peroneal nerve conduction velocity, 42.6 (1.4) m/s in AIDS patients versus 52.6 (3.3) m/s in patients without AIDS (p less than 0.0001). These findings indicate that in most HIV infected patients the severity but not the type of neuropathy depends on whether an immune deficient state has developed. Seven patients with symptomatic polyneuropathy were treated with azidothymidine (AZT) for an average of 10 months and compared with a group of five untreated patients with similar symptoms. No effect of AZT treatment on sural or median nerve amplitude or conduction velocity or on the vibratory or temperature thresholds was observed.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Regional brain glucose metabolism and blood flow in streptozocin-induced diabetic rats.

Brain regional glucose metabolism and regional blood flow were measured from autoradiographs by the uptake of [3H]-2-deoxy-D-glucose and [14C]iodoantipyrine in streptozocin-induced diabetic (STZ-D) rats. After 2 days of diabetes, glucose metabolism in the neocortex, basal ganglia, and white matter increased by 34, 37, and 8%, respectively, whereas blood flow was unchanged. After 4 mo, glucose metabolism in the same three regions was decreased by 32, 43, and 60%. This reduction was paralleled by a statistically nonsignificant reduction in blood flow in neocortex and basal ganglia. It is suggested that the decrease of brain glucose metabolism in STZ-D reflects increased ketone body oxidation and reduction of electrochemical work.

Aging↗
PubMed1990

Effect of a geriatric educational experience on graduates activities and attitudes.

Clinical geriatric dentistry has not been an important part of most dental curricula. However, changes in demographic and patient expectations signify that geriatric oral health care can no longer be equated with supplying dentures for an aging population, but must be understood as treatment of the complex needs of a dentate population. The 1975 to 1985 graduates of the University of Iowa College of Dentistry were surveyed to evaluate the influence on dental practice of a comprehensive geriatric dental curriculum introduced in 1980. The post-1980 graduates were more likely to be practicing in larger population centers and less likely to be treating patients over 75 years of age. The dentists who graduated before 1980 were more likely to be consultants in nursing homes and carrying out examination, emergency care, and/or denture care, whereas the group of dentists who graduated after 1980 and had geriatric clinical experience with frail and functionally dependent older adults were more likely to be carrying out comprehensive care. When given a list of 18 geriatric dental and gerontological topics, few differences were found between cohort groups in terms of knowledge and confidence in carrying out procedures.

Cohort Studies↗
PubMed1989

Progressive neurological dysfunction during latent HIV infection.

OBJECTIVE--To determine whether the delayed conduction through the spinal cord and peripheral nerves seen in patients with AIDS is related to infection with HIV or to the presence of an immunodeficient state. DESIGN--Two year prospective follow up study of electrophysiological measurements in subjects positive for HIV antibody but without AIDS. SETTING--HIV screening clinic and clinical departments in a university hospital in Copenhagen, Denmark. SUBJECTS--Twelve homosexual men positive for HIV antibody who had not developed AIDS. RESULTS--Eight latencies were measured: from the ankle to T12, the wrist to C7, T12 to the cerebral cortex, C7 to the cerebral cortex, the ankle to the gluteal crease (tibial nerve), the gluteal crease to T12, the wrist to Erb's point (median nerve), and Erb's point to C7. Spinal latencies increased in all subjects at C7 by a mean of 4.2% (SE 0.9%) and in all except one at T12 by a mean of 5.5% (1.0%). The conduction time from the gluteal crease to T12 was increased by a mean of 32.0% (5.0%) whereas that in the median and tibial nerves by only 5.6% (1.0%) and 2.2% (2.2%) respectively. CONCLUSIONS--A mild and slowly progressive peripheral neuropathy of the axonal type and a more severe progressive myelopathy or myeloradiculopathy occur concomitantly with early HIV infection, possibly as the result of a direct neurotropic action of HIV.

Denmark↗
PubMed1989

[Plasmapheresis in the treatment of peripheral HIV neuropathy].

Peripheral neuropathy following HIV infection is frequently seen among HIV-positive-, ARC- and AIDS patients who often complain of debilitating paresthesias. Indirect immunofluorescence technique showed antibodies directed either to myelin and/or axons and to endothelial cells of the blood vessels within the nerve tissue. Sural nerve biopsies from five patients showed demyelination, axonal degeneration and perivascular cellular infiltration. Two of the patients had nuclear inclusions and high anti-CMV titer. Plasma exchange was undertaken on five HIV infected patients which resulted in complete disappearance of symptoms in three, incomplete remission in one and no effect in one patient. The finding of autoantibodies against different nerve tissue components, cellular infiltration, positive effect of the plasma exchange and relapse suggests that autoimmunity may play a pathogenetic role in some of the HIV infected patients with peripheral neuropathy.

AIDS-Related Complex↗
PubMed1989

[Myocardial enzymes in the serum after high and low laparotomy].

The serum activities of ASAT, ALAT, LDH, creatine kinase (CK) and creatine kinase B (CK-B) were measured perioperatively in 20 patients in connection with vagotomy or subtotal/total gastrectomy and in 20 patients in connection with resection of the rectum. None of the patients presented clinical or serial electrocardiographic signs of acute myocardial infarction (AMI). ASAT, ALAT and LDH showed moderate increases postoperatively, the median values of which were within the reference range, and no statistical differences were found between the maximal values for these enzymes between patients with high and low laparotomies. In both patient categories, CK and CK-B showed marked postoperative increase and the maximal values for these enzymes were significantly higher in the group of patients subjected to high laparotomies, presumably on account of more pronounced muscle trauma in this group. The discriminative limits for CK-B as regards AMI diagnosis usually employed were found to be unsuitable after stomach and rectum surgery. The traditional myocardial enzymes must be interpreted with restraint after laparotomy as regards the diagnosis of AMI. A discriminative limit for CK-B% (maximal CK-B/total CK) of 6 is probably more suitable.

Adult↗
PubMed1989

Cholinergic dysfunction of heart, pupil, salivary glands, and urinary bladder in healthy volunteers during long-term treatment with clomipramine.

Cholinergic functions were studied in ten non-depressed healthy volunteers who were treated with 50 mg clomipramine daily for 3 weeks and subsequently with 100 mg daily for a further 3 weeks. Impairments in heart rate variation (HRV) at rest and standing, of the pupillary light response and of salivation were related to serum levels of clomipramine. Since reduction of HRV is closely related to dose (r = -0.83, P less than 10(-2] and is a better predictor of serum levels than the other measures examined, it is suggested that the easy obtainable function test of HRV at standing can be used as an estimate of over-all cholinergic dysfunction during treatment with tricyclic antidepressants.

Adult↗