Lipoprotein modifications by gingipains of Porphyromonas gingivalis.

BACKGROUND AND OBJECTIVE: Several studies have shown an association between periodontitis and cardiovascular disease (CVD). Atherosclerosis is the major cause of CVD, and a key event in the development of atherosclerosis is accumulation of lipoproteins within the arterial wall. Bacteria are the primary etiologic agents in periodontitis and Porphyromonas gingivalis is the major pathogen in the disease. Several studies support a role of modified low-density lipoprotein (LDL) in atherogenesis; however, the pathogenic stimuli that induce the changes and the mechanisms by which this occur are unknown. This study aims to identify alterations in plasma lipoproteins induced by the periodontopathic species of bacterium, P. gingivalis, in vitro. MATERIAL AND METHODS: Plasma lipoproteins were isolated from whole blood treated with wild-type and gingipain-mutant (lacking either the Rgp- or Kgp gingipains) P. gingivalis by density/gradient-ultracentrifugation and were studied using 2-dimensional gel electrophoresis followed by matrix-assisted laser desorption/ionization mass spectrometry. Porphyromonas gingivalis-induced lipid peroxidation and antioxidant levels were measured by thiobarbituric acid-reactive substances and antioxidant assay kits, respectively, and lumiaggregometry was used for measurement of reactive oxygen species (ROS) and aggregation. RESULTS: Porphyromonas gingivalis exerted substantial proteolytic effects on the lipoproteins. The Rgp gingipains were responsible for producing 2 apoE fragments, as well as 2 apoB-100 fragments, in LDL, and the Kgp gingipain produced an unidentified fragment in high-density lipoproteins. Porphyromonas gingivalis and its different gingipain variants induced ROS and consumed antioxidants. Both the Rgp and Kgp gingipains were involved in inducing lipid peroxidation. CONCLUSION: Porphyromonas gingivalis has the potential to change the expression of lipoproteins in blood, which may represent a crucial link between periodontitis and CVD.

Sclerostin, TNF-alpha and Interleukin-18 Correlate and are Together with Klotho Related to Other Growth Factors and Cytokines in Haemodialysis Patients.

Patients with chronic renal failure are known to have renal osteodystrophy (bone disease) and increased calcification of vessels. A new marker of bone disease, sclerostin, the two pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and interleukin-18 (IL-18), and the fibroblast growth factor-23 (FGF-23) receptor-associated marker Klotho were tested in 84 haemodialysis (HD) patients and in healthy controls. The patients had significantly higher levels of the three former markers than of the controls while Klotho was significantly higher in the controls. Low level, but significant, correlations were observed in the patient group when the levels of these four markers were compared to each other and to those of 5 cytokines and growth factors tested earlier; high-sensitive CRP (hsCRP), interleukin-6 (IL-6), hepatocyte growth factor (HGF), fibroblast growth factor-23 (FGF-23) and soluble urokinase plasminogen activator (suPAR). Ln sclerostin correlated positively to Ln hsTNF-alpha, Ln HGF and Ln suPAR. Ln hsTNF-alpha correlated positively to Ln sclerostin, Ln hsCRP, Ln IL-6, Ln FGF-23, Ln suPAR and Ln IL-18. Ln IL-18 correlated positively to Ln suPAR and Ln TNF-alpha. Ln Klotho correlated negatively to Ln hsCRP but did not correlate to Ln FGF-23. The markers studied here may be involved in the calcification of vessels seen in HD patients due to a combination of inflammation and bone disease. The mechanisms are still not fully known but may be of importance for future therapeutic possibilities in this group of patients.

Fibroblast growth factor 23, hepatocyte growth factor, interleukin-6, high-sensitivity C-reactive protein and soluble urokinase plasminogen activator receptor. Inflammation markers in chronic haemodialysis patients?

Sera from 84 haemodialysis (HD) patients and 68 healthy blood donors were analysed with commercially available ELISA techniques for fibroblast growth factor 23 (FGF-23), hepatocyte growth factor (HGF), interleukin-6 (Il-6), high-sensitivity C-reactive protein (hs-CRP) and soluble urokinase plasminogen activator receptor (suPAR), to find a possible correlation of FGF-23 and HGF with the earlier recognized inflammatory markers Il-6 and hs-CRP or suPAR. All patients studied had significantly elevated levels of FGF-23, HGF, hs-CRP and suPAR as compared to the controls. Il-6 and hs-CRP correlated for patients (R = 0.6) as well as for patients and controls altogether. Ln (natural logarithm) of HGF correlated weakly with Ln Il-6 and Ln CRP (R 0.28-0.37). Ln FGF-23 correlated only with Ln HGF (r = -0.25) in controls. Ln HGF correlated with ln suPAR (r = 0.6) in both patients and controls. Although elevated as compared to controls, we found no correlation of FGF-23 with the recognized inflammatory markers Il-6, hs-CRP, nor HGF or the new marker suPAR in HD patients. Ln HGF correlated with Ln Il-6, Ln CRP and Ln suPAR. Although probably involved in vessel disease, FGF-23 and HGF may play other roles than acting in inflammatory vessel disease in HD patients. Further studies are necessary to evaluate the role of these immunological markers in chronic haemodialysis patients with atherosclerosis.

Hepatocyte growth factor in patients with coronary artery disease and its relation to periodontal condition.

Hepatocyte growth factor (HGF) is an angiogenic, cardioprotective factor important for tissue and vascular repair. High levels of HGF are associated with chronic inflammatory diseases, such as coronary artery disease (CAD) and periodontitis, and are suggested as a marker of the ongoing atherosclerotic event in patients with CAD. Periodontal disease is more prevalent among patients with CAD than among healthy people. Recent studies indicate a reduced biological activity of HGF in different chronic inflammatory conditions. Biologically active HGF has high affinity to heparan sulfate proteoglycan (HSPG) on cell-membrane and extracellular matrix. The aim of the study was to investigate the serum concentration and the biological activity of HGF with ELISA and surface plasmon resonance (SPR), respectively, before and at various time points after percutaneous coronary intervention (PCI) in patients with CAD, and to examine the relationship with periodontal condition. The periodontal status of the CAD patients was examined, and the presence of P. gingivalis in periodontal pockets was analyzed with PCR. The HGF concentration was significantly higher, at all time-points, in patients with CAD compared to the age-matched controls (P< 0.001), but was independent of periodontal status. The HGF concentration and the affinity to HSPG adversely fluctuated over time, and the biological activity increased one month after intervention in patients without periodontitis. We conclude that elevated concentration of HGF but with reduced biological activity might indicate a chronic inflammatory profile in patients with CAD and periodontitis.

"Active back school", prophylactic management for low back pain: three-year follow-up of a randomized, controlled trial.

The purpose of the present study was to investigate the long-term effect of the Active Back School programme on minimizing recurrences of episodes of low back pain. Forty-three subjects were randomly allocated to the Active Back School group and 38 to the control group. There were no significant differences between the groups with regard to baseline characteristics. The Active Back School programme comprised 20 lessons each divided into a 20-min theoretical and a 40-min exercise part during a 13-week period. Nine participants (11%) dropped out during the study period. Recurrence of new low back pain episodes was significantly less (p = 0.04), and the time from inclusion to the first new low back pain episode was significantly on the side of the Active Back School group (p < 0.01). The duration of sick leave was found to be significantly shorter (p < 0.01) in the Active Back School group compared to the control group. The Active Back School reduced the recurrence and severity of new low back pain episodes at 36 months' follow-up.

Replication and discrimination of limb movement velocity.

It is well known that proprioception is composed of the senses of movement and position. Whereas tests of position sense are quite commonly used, tests of the acuity in perception of movement velocity are scarce. In the present study we examined some novel tests for assessing the sense of limb movement velocity, involving replication and discrimination of single-joint movement velocity. Specifically, we investigated: (1) whether replication of limb movement velocity is more accurate following active criterion movements as compared to passive; (2) whether antagonist muscle contraction during passive limb movement enhances velocity discrimination; (3) how criterion movement velocity influences response accuracy; (4) the relationship between movement velocity and movement extent during velocity replication; and (5) whether subjects really base discrimination of velocities on perceived velocity. Sixteen healthy subjects participated in four tests (I-IV). For each test, horizontal abductions were performed about the right glenohumeral joint from the sagittal plane. The subjects were required to actively replicate the velocity of either an active (Test I) or passive (Test II) criterion movement, or judge whether a passive/semipassive (passive during antagonist muscle contraction) movement was faster or slower than a previous passive/semipassive criterion movement (Test III/IV). The results revealed higher response accuracy for Test I compared to Test II and for slower movements compared to faster, but no difference in response accuracy between Test III and IV. For velocity discrimination, the analysis revealed that the subjects based their judgment on the difference between criterion and comparison velocity rather than time or extent cues.

Exercises and education as secondary prevention for recurrent low back pain.

BACKGROUND AND PURPOSE: Exercise and education is a common physiotherapy approach in the prevention of low back pain. A Mensendieck exercise programme consisting of exercises and ergonomical education has, in a previous study, been shown to be effective in preventing recurrent low back pain during one-year follow-up. The purpose of the present study was to evaluate the long-term effect of the Mensendieck exercise programme on people with recurrent episodes of low back pain who, when entering the study, had finished treatment for their last episode of low back pain. METHOD: A randomized controlled clinical trial in which 41 women and 36 men were allocated to either a Mensendieck or control group. The Mensendieck subjects received 20 group sessions of exercises and ergonomical education over 13 weeks. The control subjects were not offered any prophylactic therapy, but were free to receive treatment or exercises. Outcome measures were the number of recurrences of low back pain, sick leave, low back function and general functional status. RESULTS: At three-year follow-up, 11 subjects had been lost to the study. Survival analysis showed a significant reduction (p = 0.02) in subjects experiencing recurrent low back pain in the Mensendieck group compared to the control group. Significant improvements in pain and function scores were reported in both groups. There was no significant difference between the groups in pain, function or sick leave. CONCLUSION: A Mensendieck exercise programme seems efficient in reducing recurrent episodes of low back pain at three-year follow-up, but it did not influence sick leave, pain or function scores.

Position sense testing: influence of starting position and type of displacement.

OBJECTIVE: To assess the effect of starting position, target position, and various types of limb displacement on repositioning tests commonly used for clinical evaluation of rehabilitation. SETTING: Controlled laboratory environment. PARTICIPANTS: Sixteen healthy volunteer subjects. MAIN OUTCOME MEASURE: Absolute error, ie, the absolute difference between target and replicate positions. DESIGN: Each subject performed four testing procedures consisting of different types of limb displacement (active, passive, and passive during antagonist muscle contraction). For each procedure, horizontal movements were performed ipsilaterally about the right glenohumeral joint from one intermediate starting position (40 degrees ) and two extreme starting positions (0 degrees and 80 degrees ). Four fixed target positions (16 degrees , 32 degrees, 48 degrees , 64 degrees ) were presented for each starting position. The subjects were required to replicate target position after returning to the respective starting position. RESULTS: Lower repositioning errors occurred with active displacement procedures compared with passive, and with the intermediate starting position compared with the extreme. Target position, however, had no effect on repositioning errors. CONCLUSIONS: Starting position and type of displacement should be considered in interpretations and comparisons of data from clinical studies.

Reliability of position sense testing assessed with a fully automated system.

Position sense testing has increased as a tool for augmenting evaluation of joint injury. In the present study, we investigated the inter-day reliability for four different types of position sense tests using a fully automated system. The tests included (1) passive presentation/active replication, (2) passive presentation/passive replication, (3) semi-passive presentation/semi-passive replication (where semi-passive denotes passive movement during antagonist muscle contraction), and (4) active presentation/active replication. The absolute difference between presented target and replicated position was used as a measure of position sense accuracy. Ten healthy subjects who were blindfolded and seated with the arm in a moveable rig performed the tests on two occasions, separated by 3-4 days. For each type of position sense test, horizontal abduction from a starting position of 0 degrees (relative to the sagittal plane) to target positions of 32 degrees and 64 degrees, and horizontal adduction from a starting position of 80 degrees to 48 degrees and 16 degrees were conducted. A two-way ANOVA revealed no differences in absolute error between days or between testing procedures. However, intra-class correlations (ICC), which are most often used to express test-retest reliability, were moderate at best, ranging from 0.40 to 0.61 for the four types of position sense tests. Hence, the present study indicates that the ability of repositioning tests to detect alterations in proprioceptive function is limited, suggesting that their use in clinical evaluation be approached with prudence.

The effect of a Mensendieck exercise program as secondary prophylaxis for recurrent low back pain. A randomized, controlled trial with 12-month follow-up.

STUDY DESIGN: A prospective, randomized, controlled trial with a stratification block design in which a Mensendieck exercise program was compared with the experience of a control group. OBJECTIVE: To evaluate the effect of a Mensendieck program on the incidence of recurrent episodes of low back pain in patients with a history of the condition who currently are working. SUMMARY OF BACKGROUND DATA: One episode of low back pain increases the risk of further episodes of the condition. The Mensendieck approach combines education and exercise. This approach has been used for many years in Scandinavia and the Netherlands. However, the effects on low back pain have not been evaluated previously in a randomized, controlled trial. METHODS: A total of 77 men and women, mean age 39.6 years (range, 21.2-49.8 years), who had finished treatment for a low back pain episode, were stratified according to incidence of low back pain episodes and symptoms of sciatica over the preceding 3 years. The patients were assigned at random to either the Mensendieck program or a control group. The Mensendieck group received 20 group sessions of exercises and ergonomic education in 13 weeks. At 5- and 12-month follow-up examinations, the patients were assessed for recurrence of low back pain, days of sick leave, low back pain, and functional scores. RESULTS: After 12 months, there was a significant reduction in recurrent low back pain episodes in the Mensendieck group compared with the control group (P < 0.05). There was a trend toward fewer days of sick leave because of low back pain in the Mensendieck group, but no significant differences between the groups. There was reduction in pain and improvement in function in both groups, with no significant differences between the groups. CONCLUSIONS: A secondary prophylaxis Mensendieck exercise program of 20 group sessions significantly reduced the incidence of low back pain recurrences in a population with history of the condition. However, there were no differences between the groups with regard to days of sick leave, low back pain, and function.

Localized muscle fatigue decreases the acuity of the movement sense in the human shoulder.

PURPOSE: The purpose of this study was to investigate alterations in the movement sense acuity during localized muscle fatigue in the human dominant shoulder. METHODS: Fourteen healthy volunteers (8 males and 6 females) with a mean age 23 +/- 2 yr participated in the study. The subjects' ability to discriminate movement velocity relative to a reference velocity imposed over the dominant shoulder was tested following two experimental conditions: 1) Light exercise (LE), repetitive isokinetic horizontal flexion/extensions at the shoulder, ranging from 85 degrees to 20 degrees relative to the frontal plane, at 10% of maximal voluntary contraction (MVC) and 2) Hard exercise (HE), same movements as in LE, but performing MVC to fatigue. RESULTS: The results showed that subjects had a lower probability of distinguishing between different movement velocities following HE as compared with those during the LE condition (P < 0.001). When genders were compared, female subjects had a lower probability of distinguishing correctly than male subjects (P < 0.001). CONCLUSIONS: The acuity of the movement sense in the dominant shoulder is reduced in the presence of shoulder muscle fatigue. The possible influence of muscle fatigue via peripheral muscle receptors on movement sense is discussed.

Active back school: prophylactic management for low back pain. A randomized, controlled, 1-year follow-up study.

STUDY DESIGN: A randomized, controlled, single-center trial with a stratified group design. OBJECTIVE: To investigate the secondary prophylactic effect of the Active Back School program on minimizing recurrences of low back pain episodes. SUMMARY OF BACKGROUND DATA: The results of back school interventions are controversial. Previous work often used short intervention periods and low doses of practical training. However, studies with the highest methodologic scores have shown the best results, especially when conducted in occupational settings and coupled with a comprehensive rehabilitation program. METHODS: By block randomization, 19 men and 24 women were allocated to Active Back School, with 18 men and 20 women as control subjects. The Slumps test and number of low back pain episodes during the previous 36 months were used as stratification factors. There were no significant differences between the groups with regard to demographic factors and initially observed variables. Active Back School consisted of 20 lessons over a 13-week period. Each lesson was divided into a 20-minute theoretical part and a 40-minute exercise part. All participants were examined on enrollment, then 5 and 12 months after initiation of the program. Outcome measures were recurrence of low back pain episodes and number of days of sick leave. RESULTS: The recurrence of new low back pain episodes was significantly lower (P < 0.05) and the time from inclusion to the first new episode significantly longer (P < 0.01) in the Active Back School group than in the control group. In the Active Back School group, seven participants took sick leave because of low back pain episodes during the first 12 months of follow-up compared with 11 among the control subjects. The number of sick leave days was significantly lower (P < 0.05) in the Active Back School group than in the control group. CONCLUSION: Active Back School reduced the recurrence and severity of new low back pain episodes according to results of follow-up examinations performed 5 and 12 months after enrollment.