Determinants of change in perceived disability of patients with non-specific chronic low back pain.

OBJECTIVE: Change in psychophysical capacity, calculated as the ratio between physical capacity and perceived effort, may be a determinant of change in perceived disability. The aim of this study was to identify determinants for change in perceived disability, as measured with the Roland Morris Disability Questionnaire (RMDQ), in patients with non-specific chronic low back pain after rehabilitation. METHODS: Data were gathered for 84 outpatients. Psychophysical capacity (psychophysical static leg lift, psychophysical static trunk lift, and psychophysical dynamic lifting capacity), physical lifting capacity, perceived lifting effort, aerobic capacity and RMDQ were assessed. Associations between change in RMDQ and potential determinants were calculated. Variables associated with change in RMDQ were entered in a multivariate linear regression analysis (backward). RESULTS: Change in psychophysical static trunk lift (r = -0.51), psychophysical dynamic lifting capacity (r = -0.53) and psycho-physical static leg lift capacity (r = -0.23) were significantly associated with change in RMDQ. The RMDQ score at baseline (beta = -0.438), change in psychophysical dynamic lifting capacity (beta = -0.109), psychophysical static trunk lift capacity (beta = -0.038), psychophysical static leg lift capacity (beta = -0.012) and static leg lift capacity (beta = 0.007) all contributed significantly to the regression model (r2 = 52%). CONCLUSION: Improvements in psychophysical lifting capacity are determinants for a reduction in perceived disability.

Nonspecific chronic low back pain patients are deconditioned and have an increased body fat percentage.

The aim of this cross-sectional study was to compare data on the level of aerobic capacity and body composition of nonspecific chronic low back pain (CLBP) patients with normative data matched for sex, age and level of sporting activity. The study population consisted of 101 outpatients with nonspecific CLBP who had entered a rehabilitation programme. Results were as follows: the mean (standard deviation) aerobic capacity (VO2max) of CLBP patients was significantly (P<0.001) lower 7.3 (5.6) ml/kg lean body mass/min as compared with the normative data. The mean (standard deviation) body fat percentage of the patients was significantly (P<0.001) higher 3.9 % (5.9) as compared with the normative data. These results provide evidence of a reduced level of aerobic capacity and an increased body fat percentage in nonspecific CLBP patients compared with healthy participants.

Exercise capacity in non-specific chronic low back pain patients: a lean body mass-based Astrand bicycle test; reliability, validity and feasibility.

OBJECTIVE: Measurement of exercise capacity is essential in patients with non-specific chronic low back pain (CLBP). However, the conventional Astrand bicycle test is not feasible in patients with a very poor aerobic capacity. Therefore the Astrand bicycles test for non-specific CLBP patients based on lean body mass (LBM) was developed as an alternative. The aim of this study was to evaluate reliability and validity of the LBM-based Astrand test. SUBJECTS: Twenty patients with non-specific CLBP and 20 healthy subjects were included for the reliability evaluation, and 19 healthy subjects for the validity evaluation. METHOD: Patients and healthy subjects were assessed twice. Intra class correlation (ICC), repeatability coefficient (RC) and the limits of agreement (LOA) were calculated as a measure of test re-tests reliability. An ICC >or= 0.75 was considered acceptable. Validity was tested by calculating ICC between the LBM-based Astrand test and a maximal bicycle test. RESULTS: The LBM-based Astrand test shows good reliability, reflected by an ICC >or= 0.91 and 95% of the 20 patients could perform the test. However, differences with the estimated true value reflected by the RC and natural variation reflected by the LOA were substantial in patients. Validity was good, reflected by ICC >or= 0.88. CONCLUSION: The present study shows that the LBM-based Astrand test is a reliable, valid, and feasible method for patients with non-specific CLBP. However, a substantial amount of variation should be taken into account in patients when interpreting the test results clinically.

Test-retest reliability of psychophysical lift capacity in patients with non-specific chronic low back pain and healthy subjects.

OBJECTIVE: Psychophysical lift capacity tests are lifting tests in which the performance, expressed in Newtons, is divided by the perceived exertion, expressed on a Borg scale. The aim of this study was to analyse test-retest reliability of psychophysical lift capacity tests. SUBJECTS: Patients with non-specific chronic low back pain (n=20) and healthy subjects (n=20). METHODS: Psychophysical lift capacity tests were assessed during a back school intake at the Centre for Rehabilitation of the University Medical Centre Groningen. Patients on the waiting list and healthy subjects were assessed twice, with a 2-week interval between assessments. Intra-class correlation (ICC) was calculated as a measure of reliability. An ICC > or = 0.75 was considered as an acceptable reliability. Limits of agreement as a measure for natural variation were calculated. RESULTS: The psychophysical static and dynamic lift capacity tests showed good reliability (ICC > or = 0.75). The limits of agreement are substantial, indicating a considerable natural variation between test-sessions for all psychophysical tests. CONCLUSION: The psychophysical static lift capacity and dynamic lifting capacity are reliable instruments for patients with non-specific chronic low back pain and healthy subjects. However, a substantial amount of natural variation should be taken into account between 2 test sessions when interpreting the test results clinically.

[Intra-articular treatment with Hyalgan in osteoarthrosis of the knee joint: experience in clinical practice in the Czech Republic]. / Intraartikulární lécba osteoartrózy kolenních kloubu Hyalganem: zkusenosti z klinické praxe v Ceské republice.

PURPOSE OF THE STUDY: To evaluate safety and efficacy of intraarticular (IA) hyaluronic acid (HA; Hyalgan in current medical practice. MATERIAL AND METHODS: Multicenter, prospective, opened, observational study included 601 patients in 35 centers in Czech Republic. Patients had analgesics and NSAIDs on demand as rescue analgesia, but i. a. corticosteroids were not allowed. Patients received 1 series of 5 IA injectious of HA into one knee. Outcome measures were: pain at rest and on walking, patients global and assessment of therapy, Lequesne's index, consumption of NSAIDs. The patients were followed for 17 weeks (12 weeks after the last injection). RESULTS: Patients improved in all outcome measures in week 5 (1 week after the last injection) and this improvement remained constant till week 17 (p < 0.001). The patients judged activity level as better or much better for 78% of treated kness in week 5 and 85.7% in week 17. The mean consumption of rescue NSAIDs dropped fom 4 days/1 week before treatment to 1 day/week during and after Hyalgan therapy. There were no severe side effects reported. Injection site pain occurred in 6.8% patients and in 1.45% for injection, and resulted in 1.4% in withdrawal. CONCLUSION: Hyalgan provided good clinical benefits and acceptable safety profile in current medical practise. The consumption of NSAIDs dropped considerably and therefore contributed to favourable cost/benefit ratio of Hyalgan therapy.

Partial purification of a novel insect antidiuretic factor from the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), which acts on Malpighian tubules.

In this study, we report for the first time the presence of an antidiuretic factor in the head of the Colorado potato beetle (Leptinotarsa decemlineata (Say)) which acts directly on Malpighian tubules. Biologically active fractions were isolated from the head and separated using molecular weight filtration and high-performance liquid chromatography (HPLC). The resulting fractions were tested for their antidiuretic activity on single isolated Malpighian tubules. Antidiuretic activity was found in the 25% acetonitrile Sep-Pak fraction and the Cn-2 (3000-10,000 MW) and Cn-3 (<3000 MW) fractions, suggesting that the antidiuretic factor was probably a peptide of 25 to 50 amino acids. The antidiuretic factor was very potent, since after five successive fractionations on two different HPLC columns, a high level of inhibition (63%) of fluid secretion by Malpighian tubules could be observed at low dose (0.14 head-equivalent/microl). The antidiuretic factor isolated from the head of the Colorado potato beetle was not affected by repeated freezing and thawing but was sensitive to heat. The differences observed between the Colorado potato beetle antidiuretic factor and other insect diuretic and antidiuretic factors may indicate the possibility of a novel family of water regulation hormones in insects.

Replicase-mediated resistance to potato virus Y in transgenic tobacco plants.

Nicotiana tabacum 'Turkish Samsun NN' plants were transformed with nuclear inclusion b (NIb) gene sequences of potato virus Y, O strain (PVYO). The full-length construct included an additional in-frame initiation codon contiguous to the putative N-terminal amino acid codon and a stop codon replacing the C-terminal amino acid codon. Of 13 independently transformed lines, four yielded 37 (out of 100) plants in the R1 generation that were resistant to PVYO infection. Progeny of 13 out of 15 of R1 plants tested expressed resistance in the R2 generation. Conversely, 30 independently transformed tobacco lines expressing essentially the same sequence but deleted for the Gly-Asp-Asp (GDD) motif were not resistant. Two other constructs encoding either the 5'-deleted or 3'-truncated NIb gene, but harboring the GDD motif, conferred resistance to PVYO in some tobacco plants. Despite the high level of nucleotide and amino acid identity shared by strains PVYO and PVYN for the NIb gene, PVYN replication was found in all PVYO-resistant plants. However, plants of one R2 line showed reduced PVYN replication.

Gel electrophoretic analysis of chitosan hydrolysis products.

Enzymatic hydrolysis of commercial crustacean chitosan by barley chitosanases was analyzed by subjecting chitosan to electrophoresis in a 10% w/v polyacrylamide slab gel in the presence of 7 M urea and 5.5% v/v acetic acid. Chitosan migrated as a polycation. Chitosan was stained with Coomassie Brilliant Blue R-250 or visualized by ultraviolet transillumination after staining with Calcofluor White M2R. Some chitosan molecules were retarded by gel electrophoresis while small chitosan molecules migrated at the bottom of a 10% w/v polyacrylamide gel. Such analysis revealed that 96 h were necessary to convert all chitosan to oligosaccharides under our assay conditions. Chitosan oligosaccharides generated by enzymatic or chemical hydrolysis were further analyzed by electrophoresis in a 33% w/v polyacrylamide gel containing urea and acetic acid. Coomassie Brilliant Blue R-250 was found to be better than Calcofluor White M2R for staining chitosan oligosaccharides. Chitosan oligomers of four residues (tetramers) or more were easily resolved in such a polyacrylamide gel system. To our knowledge, this is the first report of a gel electrophoretic separation of chitosan and its oligosaccharides.

Lysozyme activity in animal extracts after sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

1. Lysozyme activity was detected after electrophoresis in sodium dodecyl sulfate-polyacrylamide gels containing 0.2% (W/V) autoclaved Micrococcus lysodeikticus cells as substrate. 2. Lysozyme activity appeared as clear lysis zones after incubation of opaque gels at 37 degrees C in buffered Triton X-100. 3. As low as 0.1 pg of purified hen egg white lysozyme could be detected after 16 hr incubation at pH 6.5. 4. Bands with lytic activity from kidney and pancreas acetone powders, bird's egg whites and vitelline membranes, animal sera and human saliva corresponded to c-type (Mr 14,500), g-type (Mr 20,500) or both lysozymes as far as molecular weight is concerned. 5. Some extracts, like porcine kidney, exhibited more than two bands. 6. Bands with lytic activity migrating at the level of g-type lysozymes were detected in some kidney and pancreas extracts.

Immunocytochemical localization of a wheat germ lysozyme in wheat embryo and coleoptile cells and cytochemical study of its interaction with the cell wall.

Among several wheat (Triticum aestivum L.) germ proteins able to lyse Micrococcus lysodeikticus, one lysozyme (W1A) was purified by ion-exchange chromatography, gel filtration, and preparative polyacrylamide gel electrophoresis. Polyclonal antibodies against this lysozyme were raised in rabbits. The in situ localization of W1A lysozyme was achieved by the indirect protein A-gold technique. Large amounts of W1A lysozyme were found in cell walls whereas intercellular spaces, cytoplasm, and organelles were nearly free of labeling. Specificity of labeling was assessed with several controls. In an attempt to detect the presence of binding sites, W1A lysozyme was complexed to colloidal gold. Particles were specifically distributed in large amounts over wheat embryo and coleoptile cell walls. The absence of labeling over isolated coleoptile cell walls treated with 0.1 and 0.4 molar potassium hydroxide for hemicellulose extraction indicated that W1A lysozyme binding sites were probably of hemicellulosic nature.