Biomedical subjects

I Arvidsson

Publications and source records attributed to I Arvidsson.

At least 19 recordsLinked to original sources

PubMed2001

Masked monosomy 7 in myelodysplastic syndromes is uncommon and of undetermined clinical significance.

Masked monosomy 7, i.e. detected by FISH but not by conventional cytogenetics, has been reported in varying frequency in MDS. To establish the prevalence and possible clinical significance of the aberration, we studied the 123 previously karyotyped MDS patients using FISH and a DNA probe specific for chromosome 7. Metaphase cytogenetics revealed ten patients (8%) with monosomy 7 (6 RAEB and 4 RAEB-t). FISH confirmed this result and detected four more cases (4%) with masked monosomy 7 (3 RA and 1 RARS). Thus, masked monosomy 7 is less common than has been suggested, and does not seem to carry the same prognostic weight as monosomy 7 diagnosed by metaphase cytogenetics.

Adult↗

PubMed2000

Isolation and characterization of hematopoietic progenitor/stem cells in 5q-deleted myelodysplastic syndromes: evidence for involvement at the hematopoietic stem cell level.

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal disorders characterized by ineffective hematopoiesis and frequent progression to acute myeloid leukemia. Within MDS, 5q- syndrome constitutes a distinct clinical entity characterized by an isolated deletion of the long arm of chromosome 5 (5q-), a relatively good prognosis, and infrequent transformation to acute leukemia. The cell of origin in 5q- syndrome as well as in other 5q-deleted MDS patients has not been established, but evidence for involvement of multiple myeloid (but not lymphoid) lineages has suggested that a myeloid-restricted progenitor rather than a pluripotent (lympho-myeloid) stem cell might be the primary target in most patients. Although in 9 patients no evidence of peripheral blood T-cell and only 1 case of B-cell involvement was found, the data herein support that 5q deletions occur in hematopoietic stem cells (HSCs) with a combined lympho-myeloid potential. First, in all investigated patients a minimum of 94% of cells in the minor CD34(+)CD38(-) HSC compartment were 5q deleted as determined by fluorescence in situ hybridization. Second, in 3 of 5 patients 5q aberrations were detected in a large fraction (25% to 90%) of purified CD34(+)CD19(+) pro-B cells. Furthermore, extensive functional characterization with regard to responsiveness to early-acting cytokines, long-term culture-initiating cells, and nonobese diabetic/severe combined immunodeficiency repopulating cells supported that MDS HSCs in 5q-deleted patients are CD34(+)CD38(-), but inefficient at reconstituting hematopoiesis.

Antigens, CD34↗

PubMed2000

Inter-examiner reliability in assessing passive intervertebral motion of the cervical spine.

Passive intervertebral motion of the cervical spine was assessed independently by two physical therapists. The therapists had equal backgrounds concerning education and clinical experience. Sixty-one patients seeking care for cervical problems at a private clinic were included in the study where three segments of the cervical spine and the mobility of the first rib were graded as stiff or not stiff. Data were analysed by percentage agreement and kappa coefficient which indicates inter-examiner reliability greater than expected by chance. Results demonstrated inter-examiner reliability of between 70 and 87% and kappa coefficients ranging between 0.28 and 0.43 considered to be only 'fair to moderate'.

Adult↗

PubMed2000

Back muscle fatigue in healthy men and women studied by electromyography spectral parameters and subjective ratings.

To obtain reference data for future studies of patients with low back pain, back muscle fatigue was studied by surface electromyography at L1 and L5 lumbar levels in 55 healthy subjects exerting 80% of maximal voluntary contraction of the back extensors in a sitting position. Reference data were the initial value and rate of decrease (slope) of the median frequency during the contraction. The aim was also to study the effects of contraction time, gender differences, electrode locations and correlations with torque, age and subjective ratings. Initial median frequency was 52 Hz +/- 7.5, with no difference between electrode locations; steeper slopes were found at L5 level (-0.44%/s +/- 0.25) than at L1 (-0.36%/s +/- 0.26). No right-left differences and no gender differences were found for these parameters. A correlation was observed between slope and initial median frequency, higher for men (r approximately -0.7) than for women (r approximately -0.5). Intersubject coefficient of variation for the slope was smallest for the longest (45 seconds) recording time (60-70%), but still much higher than for the initial median frequency (14%). The torque and the subjective ratings of fatigue showed no correlation with the electromyography variables. We conclude that the same reference values can be used for men and women. Owing to the large intersubject range of the slope, the clinical use of this variable may, however, be impeded.

Adult↗

PubMed1999

Neutrophil dysplasia is not a specific feature of the abnormal chromosomal clone in myelodysplastic syndromes.

In order to study if dysplastic cells are part of the abnormal chromosomal clone in myelodysplastic syndromes (MDS) we used fluorescence in situ hybridization in combination with standard May-Grünwald-Giemsa morphology (MGG/FISH) to investigate the penetration of chromosomal abnormalities into dysplastic neutrophil granulocytes in five MDS patients with documented monosomy 7 or trisomy 8 in the bone marrow at diagnosis. Neutrophil dysplasia was defined as neutrophil granulocytes with extreme hypogranulation or with nuclear abnormalities of the pelgeroid type. In one patient all dysplastic cells were derived from the abnormal chromosomal clone, while in the other four cases only 6-43% of the hypogranulated neutrophils and 33-40% of the pelgeroid granulocytes exhibited the chromosomal marker. The results suggest that neutrophil dysplasia is not a specific feature of the abnormal chromosomal clone in MDS. It is not clear, however, if the disomic dysplastic cells were derived from a parallel MDS clone with a normal karyotype, or represent residual non-clonal, normal hematopoietic cells.

Aged↗

PubMed1999

Reliability of EMG spectral parameters in repeated measurements of back muscle fatigue.

The change in median frequency of the power spectrum of the electromyographic (EMG) signal may be used as a measure of muscle fatigue. The reliability of the median frequency parameters was investigated for EMG-recording sites at L1 and L5 right and left on the erector spinae. The reliability of subjective fatigue ratings of the back muscles (Borg CR-10 scale) and of maximal trunk extension torque (MVC) was also investigated. Eleven subjects with healthy backs performed a 45-s isometric trunk extension at 80% of MVC twice a day, on three different days. Two-factor analysis of variance was made to obtain the different variances from which the standard error of measurement (SEM) and the intra class correlation coefficient (ICC) were calculated. The SEM within-day was somewhat lower than that between-days. Both were about the same at all four electrode sites. The 95% confidence interval for the studied variables was for the initial median frequency +/- 10 Hz, for the slope +/- 0.4-0.5%/s, for the MVC +/- 36 Nm and for the Borg ratings +/- 1.6. We conclude that, with the presently used method, changes or differences within these limits should be regarded as normal variability. The slope may be of limited value because of its large variability. Whether the low intraclass correlation coefficient for the EMG parameters in the presently studied test group implies a low potential in discriminating subjects with back pain can not be decisively concluded.

Adult↗

PubMed1999

Gain of chromosome 7, which marks the progression from indolent to aggressive follicle centre lymphomas, is restricted to the B-lymphoid cell lineage: a study by FISH in combination with morphology and immunocytochemistry.

In a previous fluorescent in situ hybridization (FISH) study of patients with high-grade follicle centre lymphomas (FLCs), we often found additional copies of chromosome 7 in bone marrow (BM) cell nuclei even though obvious malignant tumour cells could not always be morphologically identified in the corresponding cell smears. This raised the question whether the gains of chromosome 7 are really confined to B-lymphoid tumour cells or whether other cell lineages are also of clonal origin. In the present investigation we employed FISH in combination with immunomarkers and morphological studies on BM smears and lymph node imprints from seven patients with high-grade FCLs and diffuse large B-cell lymphomas (DLBCLs). Three out of seven BM samples were found to contain clonal CD20-positive B-lymphoid cells (range 0.4-96% of the cells) and no extra copies of chromosome 7 were detected in the myelomonocytoid or erythroid cells or in the CD3-positive T lymphocytes. All seven patients showed additional copies of chromosome 7 in the lymph nodes and, again, this cytogenetic abnormality was also restricted to the CD20-positive cells (range 0.7-80% of the cells). Thus the present findings confirm that high-grade B-cell lymphomas with or without BM engagement involve the CD20-positive B-lymphoid cells exclusively and not the T lymphocytes, erythroid or myelomonocytoid cell lineages. These findings may indicate that anti-CD20 immunotherapy could be of value in high-grade B-cell lymphomas.

Bone Marrow Diseases↗

PubMed1998

Gain of chromosome 7 marks the progression from indolent to aggressive follicle centre lymphoma and is a common finding in patients with diffuse large B-cell lymphoma: a study by FISH.

Gain of chromosome 7 represents one of the most frequent cytogenetic findings in B-cell lymphomas with a follicular growth pattern. We used fluorescence in situ hybridization (FISH) and a probe specifying chromosome 7 on lymph node imprints and/or bone marrow (BM) and peripheral blood (PB) smears from six consecutive patients with follicle centre lymphomas (FCLs) grade I or II (low-grade lymphomas), four patients with FCLs grade III and 11 patients with diffuse large B-cell lymphomas (DLBCLs) (high-grade lymphomas). We found gains of chromosome 7 in 14/18 successfully analysed cases (i.e. 2/6 FCLs grade I-II, 3/3 FLCs grade III and in 9/9 DLBCLs) using lymph node imprints. Moreover, the FISH technique demonstrated gains of chromosome 7 in 1/4 BM and 0/4 PB samples from FCLs grade I-II, in 2/4 BM and 2/4 PB specimens from FCLs grade III and in 4/9 BM and 2/9 PB samples from the DLBCLs. In contrast, morphologically recognizable lymphoma cells were seen in only 1/4 BM and 0/4 PB samples from the FCLs grade III and in 1/11 BM and 1/11 PB samples from the DLBCLs. We conclude that: (i) gain of chromosome 7 marks the progression from indolent to aggressive FCL and would appear to be a common finding in patients with FCLs grade III and in DLBCLs, (ii) clonal lymphoid cells occur frequently in BM and PB in high-grade lymphomas, making traditional staging by cytomorphology uncertain, and (iii) using gains of chromosome 7 as a marker of lymphoma cells, FISH is a useful method to detect minimal residual disease in FCLs grade III and DLBCLs.

Adult↗

PubMed1998

Trisomy 12 and lymphoplasmacytoid lymphocytes in chronic leukemic B-cell disorders.

BACKGROUND AND OBJECTIVE: Although the finding of trisomy 12 in B-cell malignancies has been extensively documented especially in B-CLL, little is known about the clonal involvement of different tissues and there are few sequential studies documenting the development of trisomy 12 during the course of the disease. The aim of this study was, therefore, to: 1) ascertain the prevalence of trisomy 12 by FISH; 2) correlate the findings of trisomy 12 with hematologic and clinical features; 3) study the trisomy 12 positive clone during the course of the disease, and 4) compare findings of trisomy 12 in different tissues. DESIGN AND METHODS: This a study of an unselected population of 118 patients with CLL or other B-cell disorders in leukemic phase from a defined geographic area. Trisomy 12 was detected by FISH. RESULTS: Trisomy 12 was found in 18 patients (15%). The aberration was significantly more common in morphologically atypical CLL (aCLL) (24%) and CLL/PL (67%) compared to typical CLL (2%) (p < 0.001). aCLL cases had predominantly lymphocytes with lymphoplasmacytoid features. Sequential studies of peripheral blood showed an increase in the proportion of trisomic cells during the observation time, mostly associated with disease progression. None of the initially trisomy 12 negative patients acquired the aberration during follow-up. The percentage of lymphocytes exhibiting trisomy 12 was significantly (p < 0.05) higher in the bone marrow than in peripheral blood. INTERPRETATION AND CONCLUSIONS: Trisomy 12 might define a distinct disease entity with atypical lymphocytes in chronic leukemic B-cell disorders.

Aged↗

PubMed1997

Differences in cell lineage involvement between MDS-AML and de novo AML studied by fluorescence in situ hybridization in combination with morphology.

We have employed fluorescence in situ hybridization (FISH) in combination with standard morphology (MGG/FISH) to identify the clonal involvement of different bone marrow cell lineages in 20 AML patients (14 MDS-AML, 6 de novo AML). Even though the number of cells belonging to the abnormal clone varied between individual cases, the percentage of clonal blasts was similar in MDS-AML and de novo AML patients. The erythropoietic cells appeared to be part of the abnormal clone in 13 of 14 patients with MDS-AML, but only in 1 of 6 with de novo AML. Similarly, clonal granulocytes were detected in 13 of 14 patients with MDS-AML, compared to 2 of 6 with de novo AML. Lymphocytes consistently displayed normal, diploid karyotype. The results suggest that it is possible to distinguish between MDS-AML and de novo AML by the use of MGG/FISH; in de novo AML the abnormal chromosomal clone is generally confined to the immature myeloid cells, while in MDS-AML mature granulocytes and erythroid cells are of clonal origin. It is, however, not possible to conclude that MDS-AML is a "multipotent" type of leukaemia, since it cannot be ruled out that the chromosomally aberrant erythroid cells and granulocytes represent surviving cells from the original MDS clone.

Adult↗

PubMed1996

Fluorescence in situ hybridization in combination with morphology detects minimal residual disease in remission and heralds relapse in acute leukaemia.

Fluorescence in situ hybridization in combination with morphology (MGG/FISH) was used to detect minimal residual disease (MRD) in complete remission (CR) in 12 cases of acute leukaemia (six MDS-AML, five de novo AML, one pre-B ALL) with numerical chromosomal aberrations at diagnosis. Residual leukaemic cells could be detected in the remission bone marrows by MGG/FISH in five patients, whereas the other seven showed no abnormalities. All five patients with signs of MRD at CR relapsed in the bone marrow with 2-9 months, in contrast to two of seven with a normal finding by MGG/FISH at CR. In both these patients a second MGG/FISH analysis showed that a subpopulation of leukaemic blasts had reappeared, 4 and 5 months prior to the leukaemia becoming clinically overt. One patient suffered a CNS relapse, but without any evidence of bone marrow involvement. The remaining four patients with no evidence of MRD at CR were still in haematological remission at follow-up after 4, 11, 12 and 13 months, respectively. We conclude that MGG/FISH seems to be a clinically useful method to detect MRD in acute leukaemia and to predict relapses, particularly when repeat studies are performed during CR.

Adult↗

PubMed1996

Classical morphology, esterase cytochemistry, and interphase cytogenetics of peripheral blood and bone marrow smears.

We used peripheral blood (PB) and bone marrow (BM) smears in the development of two methods based on cytomorphology and esterase cytochemistry in combination with fluorescence in situ hybridization (FISH). The first method involves photodocumentation of May-Grünewald-Giemsa (MGG)-stained cells, followed by destaining in methanol-acetic acid, fixation in paraformaldehyde, and digestion with protease and RNAse before FISH using alpha-satellite probes that specify chromosomes X, 7, 8, and 17. On average, two hybridization signals were seen in 94.5% of disomic BM cells. The hybridization sensitivity was found to vary, however, both among morphologically defined hematopoietic cell lineages and among differentation levels within a lineage. In the second method, an esterase staining technique was followed by the same treatment as for MGG-stained cells. The esterases and FISH signals could be simultaneously visualized and the method was found suitable for rapid screening of in situ signals in cytochemically defined granulocytes and lymphocytes but not in monocytes. The combined methods proved very useful in elucidating the clinical significance of chromosomal abnormalities seen in two cases of leukemia.

Blood Cells↗

PubMed1993

Electrical stimulation of vastus medialis and stretching of lateral thigh muscles in patients with patello-femoral symptoms.

Thirty patients with unilateral patello-femoral symptoms and a hypotrophic vastus medialis muscle were treated with transcutaneous electrical stimulation of the vastus medialis obliquus and stretching of the lateral thigh muscles twice daily for 10 weeks. Before and after treatment the position of the patella at fixed knee flexion angles and the area of the vastus medialis and vastus lateralis muscles were studied by computed tomography. Isokinetic quadriceps torque was registered with a Cybex II Dynamometer. An evaluation with a functional knee score was carried out. The healthy contralateral leg served as control in all the examinations. Clinically two-thirds of the patients had improved after 10 weeks of treatment and this improvement remained at follow-up 3.5 years later. The area of the vastus medialis and the quadriceps torque of the treated leg increased significantly, while the area of the vastus lateralis and the position of patella did not change. We conclude that transcutaneous electrical muscle stimulation of the vastus medialis and stretching of the lateral thigh muscles might be of benefit in patients with patello-femoral symptoms and a hypotrophic vastus medialis. An improvement after 10 weeks of treatment seems to predict a good long-term result.

Adolescent↗

PubMed1990

The hip joint: forces needed for distraction and appearance of the vacuum phenomenon.

Joint traction and other mobilization techniques are commonly used in physical therapy for patients with osteoarthrosis. The aim of this study has been to: (a) measure the separation of the joint surfaces in the normal hip joint during application of different forces; (b) investigate whether or not the degree of separation was influenced by the position of the joint; (c) compare hip joint laxity in men and women; (d) find the traction force needed to cause the appearance of vacuum phenomena. To achieve a separation in the hip joint, a traction force of at least 400 N must be applied. The distraction was greater in the loose packed position than in the close packed position at equal force and in both males and females. Vacuum phenomena appeared at between 400 and 600 N of traction, varying with joint position.

Adult↗

PubMed1988

Increase in myoglobin content and decrease in oxidative enzyme activities by leg muscle immobilization in man.

Biopsies from m. quadriceps femoris from the operated leg of nine patients were taken before, and 6 weeks after, knee surgery. During the whole postoperative period the operated leg was immobilized with the knee in 40-50 degrees of flexion. Myoglobin (MYO) and the enzymes citrate synthase (CS), creatine kinase (CK) and its isozymes MB (CK-MB) and mitochondrial CK (CK-MIT), aspartate aminotransferase (ASAT), phosphofructokinase (PFK) and lactate dehydrogenase (LD) were determined on the biopsies. Citrate synthase, ASAT, CK, CK-MB, CK-MIT and LD activities were decreased (12-30%) after the postoperative leg immobilization period. Phosphofructokinase did not change, while MYO content was increased (16%). In conclusion, a different control of the synthesis of oxidative enzymes and MYO is suggested, as the induced changes following immobilization were in opposite directions. The function of the increased MYO content may be to facilitate the oxygen extraction.

Adolescent↗

PubMed1987

Changes in elemental composition of human muscle fibres following surgery and immobilization. An X-ray microanalytical study.

X-ray microanalysis of single muscle fibres visualized in the electron microscope has been applied to human muscle biopsies to quantify changes of intracellular elements after knee-surgery with subsequent immobilization for 6 weeks. An increase of intracellular chlorine (Cl; P less than 0.001) and of sodium (Na; P less than 0.1) concentrations were found 1 and 6 weeks post-surgery. Intracellular potassium (K), phosphorus and sulphur concentrations were not significantly changed. The increased Cl and Na concentrations may be an indication of a decreased activity of the ATPase-dependent Na/K-pump in the sarcolemma and/or of an increased sarcolemmal permeability for Na and Cl.

Adult↗

PubMed1987

A double blind trial of NSAID versus placebo during rehabilitation.

Forty patients participated in a randomized, parallel, double blind study of piroxicam, 20 mg daily, versus placebo, given orally for 10 days following open partial meniscectomy. On day 1, 3, 7, 11, and 21 after surgery the following parameters were studied: quadriceps torque measured isokinetically; patients' assessment of pain; active and passive range of motion measured with goniometer; degree of swelling and irritation of the operated knee; and efficacy of the medication. The mean values for all parameters, except for pain assessment, were in favor of the piroxicam group. This difference was most marked on day 7 and 11 and on these days highly significant. Our findings indicate that piroxicam may be able to improve early postoperative rehabilitation.

Adolescent↗

PubMed1986

Diagnostic and operative arthroscopy of the hip.

Diagnostic and operative arthroscopies of the hip joint have been performed from an anterior approach after extension of the joint. The force needed to achieve a sufficient visualization of the hip joint was studied. In an anesthetized patient 300 Newtons (N) to 500 N was required, whereas up to 900 N was needed in an unanesthetized subject to achieve sufficient joint extension. Hip arthroscopy has been performed with a standard 5 mm Storz arthroscope. Alternatively, fluid and gas was used. It was possible to achieve good visualization of the anterior parts of the hip. Gas gave better information about the degree of degenerative arthritis while fluid was preferable for operative arthroscopy, eg, arthroscopic synovectomy. Synovial biopsies, removal of loose bodies, and partial arthroscopic synovectomy have been performed. The advantage was a very short time of rehabilitation. No serious complications occurred.

Adult↗