Search PubMed⌕ Search

Biomedical subjects

J A Aarli

Publications and source records attributed to J A Aarli.

At least 19 recordsLinked to original sources
PubMed2002

Thymectomy and anti-muscle autoantibodies in late-onset myasthenia gravis.

Thymectomy is still widely carried out in myasthenia gravis (MG) patients, but its role, especially in late-onset MG patients, is not established. These patients are immunologically heterogeneous, some with thymoma-like and others with early onset-like features. We evaluated whether any therapeutic effects of thymectomy correlate with the presence of non-acetylcholine receptor (AChR) muscle antibodies. The severity of MG, and titin and ryanodine receptor (RyR) antibodies, were assessed yearly starting from MG onset in 21 thymectomized and 22 non-thymectomized AChR antibody positive late-onset MG patients, who were followed for 2, 3 and 5 years. Clinical or pharmacological remission were seen in six of 11 titin antibody negative but none of the 10 titin antibody positive thymectomized patients, however, the non-thymectomized cases showed an opposite trend. The three MG-related deaths were all in patients with titin antibodies. There was no significant difference in MG severity between thymectomized and non-thymectomized patients; 2 years after MG onset, both groups were significantly improved. This study showed no dramatic benefit from thymectomy in late-onset MG in general. Any limited improvement appeared less likely in cases with titin and/or RyR antibodies.

Age of Onset↗
PubMed2001

[Patients with traumatic spinal cord injuries at the department of neurology, Haukeland Hospital 1952-99].

BACKGROUND: We wanted to study the cause and the segmental level of traumatic spinal cord injuries. MATERIAL AND METHODS: All 238 patients (208 men) with traumatic spinal cord injuries admitted to the Department of Neurology, Haukeland University Hospital in Bergen, Norway, from 1952 to 1999 were included. Data were obtained from medical files and studied retrospectively. RESULTS: The initial clinical level of injury was the cervical spine in 50% of the patients, the thoracic spine in 33%, and the lumbar spine in 18%. Falling (45%) and road accidents (35%) were the main causes. The mean annual number of patients with traumatic spinal cord injuries increased from three in 1952-60 to eight in 1991-99; there was an increase in high cervical injuries among those older than 60. The proportion of work-related traumatic spinal cord injuries was 42% in 1952-74 and 26% in 1975-99. INTERPRETATION: Although there has been a reduction of work-related spinal cord injuries, there is still a potential for further prevention, especially among persons of more than 60 years of age.

Accidental Falls↗
PubMed2001

[Acute infectious myelitis].

BACKGROUND: Acute myelitis is a clinical condition affecting the motor, sensor or autonomic function of the spinal cord. The etiology is often unknown, although a diversity of pathogens have been associated with acute myelitis. MATERIALS AND METHODS: Based on relevant literature we present an overview of the most important pathogens responsible for infectious acute myelitis in northern Europe, as well as recommendations regarding diagnostic guidelines. RESULTS: The pathogenic mechanisms are only partly known. Both replication of the pathogen, cellular defence mechanisms after invasion of the central nervous system, and the immune system seem to be important for the neurological damage. INTERPRETATION: Identification of a causative agent is important for the etiologic diagnosis and offers the possibility of specific treatment.

Acute Disease↗
PubMed2001

Titin and ryanodine receptor autoantibodies in dogs with thymoma and late-onset myasthenia gravis.

Similar to human autoimmune myasthenia gravis (MG), canine MG occurs spontaneously and is associated with autoantibodies against the nicotinic acetylcholine receptor (AChR). In addition to AChR, human MG patients with thymoma or late-onset MG have antibodies against titin and ryanodine receptor (RyR). The objective of this study was to establish if dogs with confirmed MG (AChR antibody titer >0.6 nmol/l) also developed titin and RyR antibodies and identify possible associations with thymoma, late age of onset, or severity of clinical signs. Sera from dogs (n=430) with previously diagnosed autoimmune MG (N=415), other immune-mediated neuromuscular disorders including polymyositis (PM) and masticatory muscle myositis (N=5), and control dogs (N=10) were evaluated for the presence of titin antibodies in ELISA using MGT-30 as antigen, a peptide representing the main immunogenic region (MIR) for human titin antibodies. Titin antibody positive sera were further examined for RyR antibodies in Western blots using a RyR fusion protein (pc2-RyR) as antigen, which covers the MIR for human MG sera. Titin antibodies were found in sera of 80/430 dogs. Thymoma was present in 11/80 and age of onset was after 4 years in 66/80 titin positive dogs. Two of the titin positive dogs had PM. RyR antibodies were found in 13/80 sera (8/13 thymoma, 12/13 age of onset after 4 years, and 1/13 PM). Neither titin nor RyR antibodies were found in sera of healthy control dogs. Acute fulminating MG was described in five dogs with both titin and RyR antibodies. From these studies we conclude that titin and RyR antibodies in canine and human MG have a similar association with thymoma, late-onset MG, and possibly with more severe forms of MG.

Age of Onset↗
PubMed2001

Polio survivors--well educated and hard working.

243 patients were diagnosed with acute poliomyelitis (polio) in Western Norway between 1950 and 1954; 186 were paralytic and 57 non-paralytic. This study examines how polio influenced their education, employment, profession, annual income, marital status and energy for leisure activities. 149 of the patients identified were alive and 98 of the matched controls responded to a questionnaire. Education length did not differ between acute paralytic polio patients, acute non-paralytic polio patients and controls. Fifty percent of the patients with residual weakness and 77 % of the patients with normal muscle power were employed, against 73 % of the controls (P=0.014). A higher proportion of patients without motor deficits had manual work than those with weakness or controls (P=0.002). There was no significant association between severity of weakness and education, employment and profession. Physical ability had been an important factor for the choice of education and profession for all the polio patients, but not for controls (P < 0.001). Annual income did not differ significantly between patients and controls. Residual weakness increased the chance of being single (P=0.023), although as many as 79% had married. 53 % of the patients with weakness claimed that fatigue prevented hobbies, compared wich 31% of the other patients and only 16% of the controls (P < 0.001). There was no significant association between severity of weakness and fatigue. In conclusion, the polio patients are generally well educated, provide their own income and marry. However, their polio has influenced choice of education and profession, and polio patients with persisting weakness differ from controls and polio patients without motor deficits regarding employment and marital status.

Aged↗
PubMed2001

Autoimmunity against the ryanodine receptor in myasthenia gravis.

Some myasthenia gravis (MG) patients have antibodies against skeletal muscle antigens in addition to the acetylcholine receptor (AChR). A major antigen for these antibodies is the Ca2+ release channel of the sarcoplasmic reticulum the ryanodine receptor (RyR). These antibodies are found mainly in MG patients with a thymoma MG and correlate with severe MG symptoms. The antibodies recognize a region near the N-terminus on the RyR, which seems to be of importance for RyR regulation. The antibodies cause allosteric inhibition of RyR function in vitro, inhibiting Ca2+ release from sarcoplasmic reticulum.

Animals↗
PubMed2000

[Arne Thorkildsen and Thorkildsen's surgery].

Arne Torkildsen (1899-1968) studied neurosurgery for one year at Queen Square and for four years (1930-34) with Wilder Penfield in Montreal. He returned to Oslo, Norway, in 1935 and took up responsibility for the neurosurgical section of the Department of Neurology of the National Hospital of Norway. In 1939, he introduced a new technique for operative treatment of hydrocephalus (ventriculocisternostomy, Torkildsen's shunt). His technique was the first successful procedure for shunting of cerebrospinal fluid and soon became internationally known and accepted as the standard operation for obstruction of the aqueduct or posterior third ventricle. In 1950, he defended his doctoral thesis at the University of Copenhagen, describing the technique and the results of the operation. He was professor of neurosurgery at the University of Cairo, Egypt 1951-1954.

Cerebrospinal Fluid Shunts↗
PubMed2000

Complement activation by titin and ryanodine receptor autoantibodies in myasthenia gravis. A study of IgG subclasses and clinical correlations.

To elucidate the mechanism of immune damage caused by titin and ryanodine receptor (RyR) autoantibodies in myasthenia gravis (MG), we studied the complement-activating capacity and the IgG subclass distribution of these autoantibodies in sera from 49 MG patients. Complement activation occurred in 38 out of 49 titin antibody positive sera, and in 14 out of 21 RyR antibody positive sera. The titin antibodies occurred only in the IgG 1 and IgG 4 subclasses, whereas the RyR antibodies occurred in all four IgG subclasses but with IgG 1 predominance. Complement-activating RyR antibodies occurred with higher frequency in sera of thymoma MG than of late-onset MG. RyR IgG 1 antibodies occurred more often in severe MG than in mild and moderate disease groups. Mean total IgG and IgG 1 titin and RyR antibody titers fell during long-time patient observation together with an improvement of the MG symptoms.

Adult↗
PubMed2000

[Polyneuropathy is an early finding in primary systemic amyloidosis].

BACKGROUND: Polyneuropathy is associated with several pathological conditions. Amyloidosis is a less common cause of polyneuropathy. Amyloidosis is caused by the accumulation of insoluble protein fibrils (amyloid) in the extracellular matrix. Primary systemic amyloidosis is caused by B-lymphocyte dyscrasia. Polyneuropathy is the first sign of primary systemic amyloidosis in about 20% of the cases, and is characterised by relentless progression, painfulness, and prominent symptoms of autonomic neuropathy. MATERIAL AND METHODS: We describe three cases of primary systemic amyloidosis that started with polyneuropathy. RESULTS: The diagnosis of primary systemic amyloidosis is often delayed more than two years after the onset of polyneuropathy. Biopsy of rectum, fat tissue, bone marrow, or peripheral nerve are diagnostic tools. INTERPRETATION: The survival of non-treated patients is about 18 months after the diagnosis. With chemotherapy the survival is prolonged to approximately 38 months.

Aged↗
PubMed2000

[Is thrombolytic therapy effective in stroke?].

BACKGROUND: The Norwegian Centre for Health Technology Assessment was asked to assess the treatment of stroke by trombolytic medication. We were also asked to include an evaluation of potential consequences for the organisation of the health care system. MATERIAL AND METHODS: Relevant literature was identified on Medline, the Cochrane Library (Systematic Reviews), and INAHTA (Systematic Reviews). Of particular importance are one study from the USA and two studies originating in Europe. RESULTS: The conclusion of the working group is that the benefit of thrombolytic treatment in the studies assessed is uncertain; furthermore, intracranial haemorrhage can occur as a complication of the treatment. INTERPRETATION: Future thrombolytic treatment of stroke patients should be carried out according to a research protocol with thorough documentation of effects as well as side effects.

Controlled Clinical Trials as Topic↗
PubMed2000

The severity of myasthenia gravis correlates with the serum concentration of titin and ryanodine receptor antibodies.

BACKGROUND: Myasthenia gravis (MG) is caused by autoantibodies to the acetylcholine receptor (AChR). Non-AChR muscle autoantibodies are present in many MG serum samples, mainly from patients with thymoma or late-onset MG. The exact relationship between MG severity and several non-AChR muscle antibodies is unknown. OBJECTIVE: To study the correlation between the severity of MG and the concentration of antibodies against striated muscle tissue sections, titin, citric acid antigen, ryanodine receptor, and AChR. SETTING: The severity of MG was graded in 146 consecutive patients with MG, and their serum samples were tested for the presence of autoantibodies. Ten patients who were titin antibody positive were observed in longitudinal follow-up. RESULTS: No significant difference was found in MG severity between late-onset and thymoma MG. Titin, citric acid antigen, and ryanodine receptor antibodies occurred significantly more often among patients with severe MG than among patients with less severe disease. Changes in MG severity correlated with changes in titin antibody titer in the individual patient. Titin antibodies showed a better longitudinal correlation with disease severity than the AChR antibodies. CONCLUSIONS: Non-AChR muscle autoantibodies occurred more frequently in severe MG regardless of MG subgroup. Thymoma per se does not generate a more severe MG. It may well be the presence of a humoral immune response to non-AChR muscle antigens such as titin, citric acid antigen, and ryanodine receptor that leads to a severe disease, not the presence of thymoma or a late age of onset. These antibodies can serve as important prognostic markers in MG regardless of the presence of thymoma.

Adult↗
PubMed2000

Epilepsy and the immune system.

OBJECTIVE: To discuss evidence that immune mechanisms are involved in the pathogenesis of some forms of epilepsy. DATA SOURCES: Computerized data sources and published indexes and articles. STUDY SELECTION: Published reports showing disorders of the immune system in patients with epilepsy and in animals with experimental epilepsy. DATA SYNTHESIS: Rasmussen encephalitis is an example of an autoimmune disorder of the central nervous system. Serum samples of patients with this disease contain antibodies to the glutamate receptor GluR3, and immunization of animals with GluR3 induces a disorder resembling the human disease. There are still few data to prove that immune mechanisms are involved in the pathogenesis of intractable childhood epilepsies other than Rasmussen encephalitis. Epilepsy is more common in patients with systemic lupus erythematosus who have antiphospholipid antibodies, and it is possible that these antibodies can lead to immune-mediated cortical damage. Immune defects in patients with epilepsy may occur as a consequence of long-term antiepileptic treatment or may represent a genetic coupling to the convulsive disorder. CONCLUSION: The finding of an immunological basis may offer new modalities for the treatment of selected cases of intractable partial epilepsies.

Adult↗
PubMed2000

Autoantibodies in thymoma-associated myasthenia gravis with myositis or neuromyotonia.

BACKGROUND: About 50% of patients with thymoma have paraneoplastic myasthenia gravis (MG). Myositis and myocarditis or neuromyotonia (NMT) will also develop in some. Patients with thymoma-associated MG produce autoantibodies to a variety of neuromuscular antigens, particularly acetylcholine receptor (AChR), titin, skeletal muscle calcium release channel (ryanodine receptor [RyR]), and voltage-gated potassium channels (VGKC). OBJECTIVE: To examine whether neuromuscular autoantibodies in patients with thymoma correlate with specific clinical syndromes. METHODS: Serum and plasma samples from 19 patients with thymoma-associated MG, of whom 5 had myositis and 6 had NMT, underwent testing for antibodies to AChR, titin, RyR, and VGKC. RESULTS: Antibodies to AChR and titin were found in 19 and 17 patients, respectively. Antibodies to RyR correlated with the presence of myositis (P = .03); they were found in all 5 patients with myositis and in only 1 patient with NMT, but also in 4 of 8 patients with neither disease. Antibodies to VGKC were found in 4 patients with NMT, 1 of 3 patients undergoing testing for myositis, and 2 of 7 patients undergoing testing with neither comorbidity. Presence of RyR antibodies correlated with high levels of titin antibodies. CONCLUSIONS: The results appear to distinguish partially between 3 groups of patients with thymoma-associated MG: the first with RyR antibodies and myositis or myocarditis, the second with NMT without RyR antibodies, and the third without RyR antibodies, myositis, or NMT. Differences in the thymoma may underlie these pathologic associations.

Adult↗
PubMed2000

Muscle autoantibodies in subgroups of myasthenia gravis patients.

Myasthenia gravis (MG) is caused by autoantibodies to the acetylcholine receptor (AChR), but several other muscle autoantibodies have also been identified in patient sera. We studied muscle autoantibodies against AChR, striated muscle tissue sections (SH), titin, citric acid antigen (CA), and ryanodine receptor (RyR) in sera from 146 consecutive MG patients to evaluate whether a single test or several tests together can predict a thymoma. The MG patients were divided into five subgroups; ocular MG, early-onset MG (< 50 years), late-onset MG (> 50 years), MG with thymoma, and AChR antibody negative MG. AChR, SH, titin, CA, and RyR antibodies were detected in 85%, 34%, 34%, 25%, and 14% of the MG patients, respectively. For thymoma MG, AChR, SH, titin, CA, and RyR antibodies were detected in 100%, 75%, 95%, 70%, and 70% respectively. SH, titin, CA, RyR antibodies, and computed tomography of the anterior mediastinum have similar sensitivity for thymoma MG. The specificity of RyR, titin, CA, and SH antibodies for thymoma was 70%, 39%, 38%, and 31%, respectively, which is significantly higher for RyR antibodies than for the others. No single muscle antibody assay can predict a thymoma, and a combination of several antibody assays is preferred, although RyR antibody testing alone showed 70% sensitivity and specificity for thymoma MG. SH and CA antibodies provided only little additional information.

Adult↗
PubMed2000

Risk of symptoms related to late effects of poliomyelitis.

OBJECTIVE: To compare the risk of developing symptoms related to late effects of poliomyelitis between polio patients and persons of similar age and sex without history of poliomyelitis. MATERIAL AND METHODS: The study comprised information on 148 patients with prior poliomyelitis and 115 persons with no history of poliomyelitis. Information was obtained by questionnaire and analyzed by multiple logistic regression method. RESULTS: The risk of experiencing two or more symptoms was significantly higher among the polio patients than among the persons without history of poliomyelitis. The elevation in risk was less pronounced in the nonparalytic group (OR = 2.35; 95% CI = 0.92-5.97) than the group with permanent muscular weakness (OR = 8.84; 95% CI =4.32-18.09). CONCLUSIONS: Although symptoms defined in the PPS are unspecific and may occur in the general population, the risk for developing such symptoms are higher among the polio victims. The difference in risk among nonparalytic and paralytic patients may depend on the extent of motor neuron damage in the acute stage.

Aged↗