Osteopathic research: elephants, enigmas, and evidence

Background

The growth and acceptance of osteopathic physicians as conventional medical practitioners in the United States has also raised questions about the distinctive aspects of osteopathic medicine. Although the use of osteopathic manipulative treatment (OMT) and a focus on primary care are most often cited as rationales for the uniqueness of osteopathic medicine, an osteopathic professional identity remains enigmatic.

Discussion

The fledgling basic osteopathic research efforts of the early and mid-twentieth century have not been sustained and expanded over time. Thus, there is presently a scarcity of basic mechanistic and translational research that can be considered to be uniquely osteopathic. To be sure, there have been advances in osteopathic clinical trials, particularly those involving OMT for low back pain. Meta-analysis of these low back pain trials has provided evidence that: (1) OMT affords greater pain reduction than active or placebo control treatments; (2) the effects of OMT are comparable regardless of whether treatment is provided by fully-licensed osteopathic physicians in the United States or by osteopaths in the United Kingdom; and (3) the effects of OMT increase over time. However, much more clinical research remains to be done. The planning and implementation of a large longitudinal study of the natural history and epidemiology of somatic dysfunction, including an OMT component, represents a much-needed step forward. Osteopathic medicine's use of OMT and its focus on primary care are not mutually exclusive aspects of its uniqueness. The intersection of these fundamental aspects of osteopathic medicine suggests that the profession may successfully adopt a generic strategy of "focused differentiation" to attain a competitive advantage in the health care arena. While there are both requisite demands and risks for the osteopathic profession in adopting such a strategy, these are reasonable in relation to the potential rewards to be attained. To help promote an osteopathic identity, "omtology" and its derivative terms are recommended in referring to the study of OMT.

Conclusion

The osteopathic profession should adopt a coherent strategy for developing and promoting its identity. Failure to do so will likely ensure that osteopathic medicine remains "stuck in the middle."     

Efficacy of osteopathic manipulation as an adjunctive treatment for hospitalized patients with pneumonia: a randomized controlled trial

Background

The Multicenter Osteopathic Pneumonia Study in the Elderly (MOPSE) is a registered, double-blinded, randomized, controlled trial designed to assess the efficacy of osteopathic manipulative treatment (OMT) as an adjunctive treatment in elderly patients with pneumonia.

Methods

406 subjects aged ≥ 50 years hospitalized with pneumonia at 7 community hospitals were randomized using concealed allocation to conventional care only (CCO), light-touch treatment (LT), or OMT groups. All subjects received conventional treatment for pneumonia. OMT and LT groups received group-specific protocols for 15 minutes, twice daily until discharge, cessation of antibiotics, respiratory failure, death, or withdrawal from the study. The primary outcomes were hospital length of stay (LOS), time to clinical stability, and a symptomatic and functional recovery score.

Results

Intention-to-treat (ITT) analysis (n = 387) found no significant differences between groups. Per-protocol (PP) analysis (n = 318) found a significant difference between groups (P = 0.01) in LOS. Multiple comparisons indicated a reduction in median LOS (95% confidence interval) for the OMT group (3.5 [3.2-4.0] days) versus the CCO group (4.5 [3.9-4.9] days), but not versus the LT group (3.9 [3.5-4.8] days). Secondary outcomes of duration of intravenous antibiotics and treatment endpoint were also significantly different between groups (P = 0.05 and 0.006, respectively). Duration of intravenous antibiotics and death or respiratory failure were lower for the OMT group versus the CCO group, but not versus the LT group.

Conclusions

ITT analysis found no differences between groups. PP analysis found significant reductions in LOS, duration of intravenous antibiotics, and respiratory failure or death when OMT was compared to CCO. Given the prevalence of pneumonia, adjunctive OMT merits further study.     

Avian influenza: an osteopathic component to treatment

Avian influenza is an infection caused by the H5N1 virus. The infection is highly contagious among birds, and only a few known cases of human avian influenza have been documented. However, healthcare experts around the world are concerned that mutation or genetic exchange with more commonly transmitted human influenza viruses could result in a pandemic of avian influenza. Their concern remains in spite of the fact that the first United States vaccine against the H5N1 virus was recently approved. Under these circumstances the fear is that a pandemic of avian influenza could result in the kind of mortality that was seen with the Spanish influenza pandemic of 1918–1919, where the number of deaths was estimated to be as high as 40 million people. Retrospective data gathered by the American Osteopathic Association shortly after the 1918–1919 influenza pandemic have suggested that osteopathic physicians (DOs), using their distinctive osteopathic manipulative treatment (OMT) methods, observed significantly lower morbidity and mortality among their patients as compared to those treated by allopathic physicians (MDs) with standard medical care available at the time. In light of the limited prevention and treatment options available, it seems logical that a preparedness plan for the treatment of avian influenza should include these OMT procedures, provided by DOs and other healthcare workers capable of being trained to perform these therapeutic interventions. The purpose of this paper is to discuss the characteristics of avian influenza, describe the success of DOs during the 1918–1919 Spanish influenza pandemic, describe the evidence base for the inclusion of OMT as part of the preparedness plan for the treatment of avian influenza, and describe some of the specific OMT procedures that could be utilized as part of the treatment protocol for avian influenza patients.     

Chronic Inflammatory Disease and Osteopathy: A Systematic Review

Background

Chronic inflammatory diseases (CID) are globally highly prevalent and characterized by severe pathological medical conditions. Several trials were conducted aiming at measuring the effects of manipulative therapies on patients affected by CID. The purpose of this review was to explore the extent to which osteopathic manipulative treatment (OMT) can be benefi-cial in medical conditions also classified as CID.

Methods

This review included any type of experimental study which enrolled sub-jects with CID comparing OMT with any type of control procedure. The search was conducted on eight databases in January 2014 using a pragmatic literature search approach. Two independent re-viewers conducted study selection and data extraction for each study. The risk of bias was evaluated according to the Cochrane methods. Heterogeneity was assessed and meta-analysis performed where possible.

Results

10 studies met the inclusion criteria for this review enrolling 386 subjects. The search identified six RCTs, one laboratory study, one cross-over pilot studies, one observation-al study and one case control pilot study. Results suggest a potential effect of osteopathic medicine on patients with medical pathologies associated with CID (in particular Chronic Obstructive Pul-monary Disease (COPD), Irritable Bowel Syndrome, Asthma and Peripheral Arterial Disease) com-pared to no treatment or sham therapy although data remain elusive. Moreover one study showed possible effects on arthritis rat model. Meta-analysis was performed for COPD studies only show-ing no effect of any type of OMT applied versus control. No major side effects were reported by those receiving OMT.

Conclusion

The present systematic review showed inconsistent data on the effect of OMT in the treatment of medical conditions potentially associated with CID, however the OMT appears to be a safe approach. Further more robust trials are needed to determine the direction and magnitude of the effect of OMT and to generalize favorable results.     

Osteopathic Manipulative Treatment as a Useful Adjunctive Tool for Pneumonia

Pneumonia, the inflammatory state of lung tissue primarily due to microbial infection, claimed 52,306 lives in the United States in 2007¹ and resulted in the hospitalization of 1.1 million patients². With an average length of in-patient hospital stay of five days², pneumonia and influenza comprise significant financial burden costing the United States $40.2 billion in 2005³. Under the current Infectious Disease Society of America/American Thoracic Society guidelines, standard-of-care recommendations include the rapid administration of an appropriate antibiotic regiment, fluid replacement, and ventilation (if necessary). Non-standard therapies include the use of corticosteroids and statins; however, these therapies lack conclusive supporting evidence⁴. (Figure 1)Osteopathic Manipulative Treatment (OMT) is a cost-effective adjunctive treatment of pneumonia that has been shown to reduce patients’ length of hospital stay, duration of intravenous antibiotics, and incidence of respiratory failure or death when compared to subjects who received conventional care alone⁵. The use of manual manipulation techniques for pneumonia was first recorded as early as the Spanish influenza pandemic of 1918, when patients treated with standard medical care had an estimated mortality rate of 33%, compared to a 10% mortality rate in patients treated by osteopathic physicians⁶. When applied to the management of pneumonia, manual manipulation techniques bolster lymphatic flow, respiratory function, and immunological defense by targeting anatomical structures involved in the these systems^{7,8, 9, 10}.The objective of this review video-article is three-fold: a) summarize the findings of randomized controlled studies on the efficacy of OMT in adult patients with diagnosed pneumonia, b) demonstrate established protocols utilized by osteopathic physicians treating pneumonia, c) elucidate the physiological mechanisms behind manual manipulation of the respiratory and lymphatic systems. Specifically, we will discuss and demonstrate four routine techniques that address autonomics, lymph drainage, and rib cage mobility: 1) Rib Raising, 2) Thoracic Pump, 3) Doming of the Thoracic Diaphragm, and 4) Muscle Energy for Rib 1.^5,11     

Rediscovering the classic osteopathic literature to advance contemporary patient-oriented research: A new look at diabetes mellitus

Patient care experiences represent opportunities for establishing theories, testable hypotheses, and data to assess the potential use of osteopathic manipulative treatment in various disease conditions. The re-analysis of Bandeen's 1949 raw data described herein summarizes the effects of osteopathic manipulative treatment involving pancreatic stimulatory and inhibitory techniques in diabetic and non-diabetic patients seen over a 25-year period of clinical practice. Bandeen's data demonstrate a reduction in blood glucose levels at 30 and 60 minutes following pancreatic stimulation in 150 diabetic patients, and an elevation in blood glucose levels at 30 and 60 minutes following pancreatic inhibition in 40 non-diabetic patients. Such patient-oriented research conducted during the classic era of osteopathy in the United States provides a foundation and data for generating hypotheses about the potential mechanisms of action of osteopathic manipulative treatment. Osteopathic investigators would be well-served to rediscover the classic osteopathic literature to help advance contemporary evidence-based medicine.     

Osteopathic manipulative treatment and its relationship to autonomic nervous system activity as demonstrated by heart rate variability: a repeated measures study

Background

Osteopathic manipulative treatment (OMT) and ultrasound physical therapy (UPT) are commonly used for chronic low back pain. Although there is evidence from a systematic review and meta-analysis that OMT generally reduces low back pain, there are no large clinical trials that specifically assess OMT efficacy in chronic low back pain. Similarly, there is a lack of evidence involving UPT for chronic low back pain.

Methods

The OSTEOPAThic Health outcomes In Chronic low back pain (OSTEOPATHIC) Trial is a Phase III randomized controlled trial that seeks to study 488 subjects between August 2006 and June 2010. It uses a 2 × 2 factorial design to independently assess the efficacy of OMT and UPT for chronic low back pain. The primary outcome is a visual analogue scale score for pain. Secondary outcomes include back-specific functioning, generic health, work disability, and satisfaction with back care.

Conclusion

This randomized controlled trial will potentially be the largest involving OMT. It will provide long awaited data on the efficacy of OMT and UPT for chronic low back pain.

Trial registration

http://www.clinicaltrials.gov, NCT00315120     

O-Methylthreonine Inhibition of Growth and of Threonine Deaminase in Escherichia coli

O-methylthreonine (OMT), an isosteric analogue of isoleucine, markedly inhibited growth of Escherichia coli 15. This inhibition was overcome most effectively by addition of isoleucine, valine, or leucine to the medium and less effectively by addition of threonine. The dipeptide, valylleucine, also relieved the OMT-induced inhibition but only after a lag period, suggesting that valine and leucine, liberated by dipeptidase action, compete with OMT for entry into the cell. OMT was activated and transferred to transfer ribonucleic acid (RNA) by isoleucyl-RNA synthetase in vitro. The rate of OMT incorporation into protein of intact cells was comparable to that of isoleucine. In contrast to isoleucine, very high concentrations of OMT were required to inhibit threonine deaminase, and the inhibition was strictly competitive with threonine. In addition, OMT inhibited a threonine deaminase preparation desensitized to isoleucine inhibition.     

Impact of Osteopathic Treatment on Pain in Adult Patients with Cystic Fibrosis – A Pilot Randomized Controlled Study

Background

Pain is a common complication in patients with cystic fibrosis (CF) and is associated with shorter survival. We evaluated the impact of osteopathic manipulative treatment (OMT) on pain in adults with CF.

Methods

A pilot multicenter randomized controlled trial was conducted with three parallel arms: OMT (group A, 16 patients), sham OMT (sham treatment, group B, 8 patients) and no treatment (group C, 8 patients). Medical investigators and patients were double-blind to treatment for groups A and B, who received OMT or sham OMT monthly for 6 months. Pain was rated as a composite of its intensity and duration over the previous month. The evolution of chest/back pain after 6 months was compared between group A and groups B+C combined (control group). The evolution of cervical pain, headache and quality of life (QOL) were similarly evaluated.

Results

There was no statistically significant difference between the treatment and control groups in the decrease of chest/back pain (difference = −2.20 IC95% [−4.81; 0.42], p = 0.098); also, group A did not differ from group B. However, chest/back pain decreased more in groups A (p = 0.002) and B (p = 0.006) than in group C. Cervical pain, headache and QOL scores did not differ between the treatment and control groups.

Conclusion

This pilot study demonstrated the feasibility of evaluating the efficacy of OMT to treat the pain of patients with CF. The lack of difference between the group treated with OMT and the control group may be due to the small number of patients included in this trial, which also precludes any definitive conclusion about the greater decrease of pain in patients receiving OMT or sham OMT than in those with no intervention.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01293019","term_id":"NCT01293019"}}NCT01293019     

Oxymatrine synergistically enhances antitumor activity of oxaliplatin in colon carcinoma through PI3K/AKT/mTOR pathway

Oxymatrine (OMT), one of the main active components of extracts from the dry roots of Sophora flavescens, has been reported to possess many pharmacological properties including cancer-preventive and anti-cancer effects. The aim of the present study is to explore the efficiency of combination therapy with OMT and oxaliplatin (OXA) and identify the in vitro and in vivo cytotoxicity on colon cancer lines (HT29 and SW480) and mice model. Cells were treated with OMT and/or OXA and subjected to cell viability, colony formation, apoptosis, cell cycle, western blotting, xenograft tumorigenicity assay and immunohistochemistry. The results demonstrated that OMT and OXA inhibited the proliferation of colon cancer cells, and combination therapy of OMT and OXA resulted in a combination index?<?1, indicating a synergistic effect. Co-treatment with OMT and OXA caused G0/G1 phase arrest by upregulating P21, P27 and downregulating cyclin D, and induced apoptosis through decreasing the expression of p-PI3K, p-AKT, p-mTOR, p-p70S6K. In addition, pretreatment with a specific PI3K/AKT activator (IGF-1) significantly neutralized the pro-apoptotic activity of OXA?+?OMT, demonstrating the important role of PI3K/AKT in this process. Moreover, in nude mice model, co-treatment displayed more efficient inhibition of tumor weight and volume on SW480 xenograft mouse model than single-agent treatment with OXA or OMT. Immunohistochemistry analysis suggests the combinations greatly suppressed tumor proliferation, which consistent with our in vitro results. In conclusion, our findings highlight that the combination therapy with OMT and OXA exerted synergistic antitumor effects in colon cancer cells through PI3K/AKT/mTOR pathway and combination treatment with OMT and OXA would be a promising therapeutic strategy for colon carcinoma treatment.     

The Analgesic Effect and Mechanism of the Combination of Sodium ferulate and Oxymatrine

Sodium ferulate (SF) and Oxymatrine (OMT) were compounds extracted from Chinese herbs, and have been used in clinical treatment of heart and hepatic diseases, respectively, in China for many years. The objective of this study was to examine the analgesic effect and the mechanism of the combined treatment of SF and OMT. Using the animal pain models by applying Acetic Acid Writhing Test and Formalin Test, the combination of SF and OMT showed significant analgesic effect in dose-dependent manner. In vitro, the combined treatment inhibited the increase in intracellular calcium concentration evoked by capsaicin in the dorsal root ganglion neurons. Importantly, a synergistic inhibitory effect of SF and OMT on the capsaicin-induced currents was demonstrated by whole-cell patch-clamp. Our results suggest that SF and OMT cause significant analgesic effect which maybe related to the synergistic inhibition of transient receptor potential vanilloid-1.     

Muscle functional magnetic resonance imaging and acute low back pain: a pilot study to characterize lumbar muscle activity asymmetries and examine the effects of osteopathic manipulative treatment

Background

Muscle functional magnetic resonance imaging (mfMRI) measures transverse relaxation time (T2), and allows for determination of the spatial pattern of muscle activation. The purposes of this pilot study were to examine whether MRI-derived T2 or side-to-side differences in T2 (asymmetries) differ in low back muscles between subjects with acute low back pain (LBP) compared to asymptomatic controls, and to determine if a single osteopathic manipulative treatment (OMT) session alters these T2 properties immediately and 48-hours after treatment.

Methods

Subjects with non-specific acute LBP (mean score on 1-10 visual analog score = 3.02 ± 2.81) and asymptomatic controls (n = 9/group) underwent an MRI, and subsequently the LBP subjects received OMT and then underwent another MRI. The LBP subjects reported back for an additional MRI 48-hours following their initial visit. T2 and T2 asymmetry were calculated from regions of interest for the psoas, quadratus lumborum (QL), multifidus, and iliocostalis lumborum/longissimus thoracis (IL/LT) muscles.

Results

No differences were observed between the groups when T2 was averaged for the left and right side muscles. However, the QL displayed a significantly greater T2 asymmetry in LBP subjects when compared to controls (29.1 ± 4.3 vs. 15.9 ± 4.1%; p = 0.05). The psoas muscle also displayed a relatively large, albeit non-significant, mean difference (22.7 ± 6.9 vs. 9.5 ± 2.8%; p = 0.11). In the subjects with LBP, psoas T2 asymmetry was significantly reduced immediately following OMT (25.3 ± 6.9 to 6.1 ± 1.8%, p = 0.05), and the change in LBP immediately following OMT was correlated with the change in psoas T2 asymmetry (r = 0.75, p = 0.02).

Conclusion

Collectively, this pilot work demonstrates the feasibility of mfMRI for quantification and localization of muscle abnormalities in patients with acute low back pain. Additionally, this pilot work provides insight into the mechanistic actions of OMT during acute LBP, as it suggests that it may attenuate muscle activity asymmetries of some of the intrinsic low back muscles.     

Oxymatrine exerts protective effects on osteoarthritis via modulating chondrocyte homoeostasis and suppressing osteoclastogenesis

Osteoarthritis (OA) is a common degenerative disease characterized by the progressive destruction both articular cartilage and the subchondral bone. The agents that can effectively suppress chondrocyte degradation and subchondral bone loss are crucial for the prevention and treatment of OA. Oxymatrine (OMT) is a natural compound with anti‐inflammatory and antitumour properties. We found that OMT exhibited a strong inhibitory effect on LPS‐induced chondrocyte inflammation and catabolism. To further support our results, fresh human cartilage explants were treated with LPS to establish an ex vivo degradation model, and the results revealed that OMT inhibited the catabolic events of LPS‐stimulated human cartilage and substantially attenuated the degradation of articular cartilage ex vivo. As subchondral bone remodelling is involved in OA progression, and osteoclasts are a unique cell type in bone resorption, we investigated the effects of OMT on osteoclastogenesis, and the results demonstrated that OMT suppresses RANKL‐induced osteoclastogenesis by suppressing the RANKL‐induced NFATc1 and c‐fos signalling pathway in vitro. Further, we found that the anti‐inflammatory and anti‐osteoclastic effects of oxymatrine are mediated via the inhibition of the NF‐κB and MAPK pathways. In animal studies, OMT suppressed the ACLT‐induced cartilage degradation, and TUNEL assays further confirmed the protective effect of OMT on chondrocyte apoptosis. MicroCT analysis revealed that OMT had an attenuating effect on ACLT‐induced subchondral bone loss in vivo. Taken together, these results show that OMT interferes with the vicious cycle associated with OA and may be a potential therapeutic agent for abnormal subchondral bone loss and cartilage degradation in osteoarthritis.     

Effect of 2,4-dichlorophenoxyacetic acid on the activity of o-methyltransferase in carrot cell culture

The activity of caffeic acid-O-methyltransferase (OMT) in carrot cells was greatly affected by the amount of 2,4-dichlorophenoxyacetic acid (2,4-D) supplemented to the culture medium. The OMT fraction was purified by (NH₄)₂SO₄ followed by ultrafiltration and gel filtration or DEAE-Sephadex chromatography after cells were cultured in the medium containing [2-¹⁴C]-2,4-D. Thus, this purified fraction revealed high OMT activity and was still radioactive. The OMT activity was about eight-fold higher (or more) in cells cultured at 0.05 ppm 2,4-D than in those at 1.0 ppm 2,4-D. The ratio of radioactivity to OMT activity was about four-fold higher in cells cultured at 1.0 ppm 2,4-D than those at 0.05 ppm 2,4-D. On the other hand, the OMT fraction was separated into two radioactive protein fractions by DEAE-Sephadex chromatography. The radioactive fractions became Et₂O-soluble after HCl hydrolysis, but not after salt-urea treatment. From these results, it was concluded that 2,4-D is covalently bound to proteins in the OMT fraction. Such 2,4-D protein conjugates may play a role in the regulation of OMT activity.     

Impact of different exercise training modalities on the coronary collateral circulation and plaque composition in patients with significant coronary artery disease (EXCITE trial): study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: Exercise training (ET) in addition to optimal medical therapy (OMT) in patients with stable coronary artery disease (CAD) has been demonstrated to be superior to percutaneous coronary interventions (PCI) with respect to the composite endpoint of death, myocardial infarction, stroke, revascularization and hospitalization due to worsening of angina. One mechanism leading to this superiority discussed in the literature is the increase in coronary collateral blood flow due to ET. Until now, data demonstrating the positive effect of ET on the collateral blood flow and the functional capacity of the coronary collateral circulation are still lacking.Methods/designThe EXCITE trial is a three-armed randomized, prospective, single-center, open-label, controlled study enrolling 60 patients with stable CAD and at least one significant coronary stenosis (fractional flow reserve <=0.75). The study is designed to compare the influence and efficacy of two different 4-week ET programs [high-intensity interval trainings (IT) versus moderate-intensity exercise training (MT) in addition to OMT] versus OMT only on collateral blood flow (CBF). The primary efficacy endpoint is the change of the CBF of the target vessel after 4 weeks as assessed by coronary catheterization with a pressure wire during interruption of the antegrade flow of the target vessel by balloon occlusion. Secondary endpoints include the change in plaque composition as assessed by intravascular ultrasound (IVUS) after 4 weeks, myocardial perfusion as analyzed in MRI after 4 weeks and 12 months, peak oxygen uptake (V02 peak), change in endothelial function and biomarkers after 4 weeks, 3, 6 and 12 months. The safety endpoint addresses major adverse cardiovascular events (death from cardiovascular cause, myocardial infarction, stroke, TIA, target vessel revascularization or hospitalization) after 12 months. DISCUSSION: The trial investigates whether ET for 4 weeks increases the CBF in patients with significant CAD compared to a sedentary control group. It also examines the impact of two intensities of ET on the CBF as well as the histological plaque composition. The trial started recruitment in June 2009 and will complete recruitment until June 2012. First results are expected in December 2012 (4-week follow-up), final results (12-month long-term secondary endpoint) in December 2013.Trial registrationClinical trial registration information-URL: www.clinicaltrials.gov.Unique identifier: NCT01209637.     

Primary Reasons for Osteopathic Consultation: A Prospective Survey in Quebec

Background

Osteopathy is an increasingly popular health care modality to address pain and function in the musculoskeletal system, organs and the head region, as well as functional somatic syndromes. Although osteopathy is recommended principally in guidelines for management of back pain, osteopaths'' scope of practice is wide, albeit poorly defined. In order to understand better the practice of osteopathy, this study aimed to investigate the most common reasons for osteopathic consultations in clinical settings in Quebec.

Methods

A prospective survey of members of the Registre des ostéopathes du Québec was conducted to examine demographics in osteopathic practices, as well as patients'' primary reasons for consultations over a two-week period. The questionnaire was devised following a literature review and refined and verified with two stages of expert input.

Results

277 osteopaths (60.1% response rate) responded to the survey notice. 14,002 patients'' primary reasons for consultations were reported in completed questionnaires and returned by practicing osteopaths. Musculoskeletal pain located in the spine, thorax, pelvis and limbs was the most common reason for consultations (61.9%), with females consulting most commonly for cervical pain and males for lumbar pain. Perinatal and paediatric (11.8%), head (9.1%), visceral (5.0%) and general concerns (4.8%) were the other most common reasons for consultations. Preventive care represented the remaining 0.3%.

Interpretation

The nature of primary reasons for osteopathic consultations, coupled with documented satisfaction of patients with this approach, suggest a future for multidisciplinary collaborative health care including osteopathy. Results of this survey may contribute to informing physicians and others pending regulation of Quebec osteopaths, and also provide direction for future clinical research and guidelines development.     

Application of carborundum abrasion for investigating the leaf epidermis: molecular cloning of Catharanthus roseus 16-hydroxytabersonine-16-O-methyltransferase

The Madagascar periwinkle (Catharanthus roseus) produces the well-known and remarkably complex anti-cancer dimeric alkaloids vinblastine and vincristine that are derived from the coupling of vindoline and catharanthine monomers. This study describes the novel application of a carborundum abrasion (CA) technique for large-scale isolation of leaf epidermis-enriched proteins in order to purify to apparent homogeneity 16-hydroxytabersonine-16-O-methyltransferase (16OMT), which catalyses the second of six steps in the conversion of tabersonine into vindoline, and to clone the gene. Functional expression and biochemical characterization of recombinant 16OMT demonstrated its very narrow substrate specificity and high affinity for 16-hydroxytabersonine. In addition to allowing the cloning of this gene, the CA technique clearly showed that 16OMT is predominantly expressed in Catharanthus leaf epidermis. The results provide compelling evidence that most of the pathway for vindoline biosynthesis, including the O-methylation of 16-hydroxytabersonine, occurs exclusively in the leaf epidermis, with subsequent steps occurring in other leaf cell types.     

Identification, purification, and characterization of S-adenosyl-L-methionine: isoliquiritigenin 2'-O-methyltransferase from alfalfa (Medicago sativa L.).

An O-methyltransferase (OMT) which methylates the 2'-hydroxyl of isoliquiritigenin (2',4,4'-trihydroxychalcone) was identified in alfalfa (Medicago sativa L.) seedlings and cell cultures. The OMT activity increased during early stages of seedling development and was predominantly located in roots. Treatment of alfalfa cell cultures with an elicitor from yeast resulted in a fivefold increase in chalcone OMT activity, whereas treatment of seedlings with CuCl2 caused a reduction in activity. The chalcone OMT was purified to near homogeneity from elicited alfalfa cell cultures. Only one form of the enzyme was found. It consisted of an active monomer of subunit Mr 43,000 which could be photoaffinity labeled with S-adenosyl-L-[methyl-3H]methionine. The purified OMT had a pH optimum of 9.0, pI of 4.7, and was highly specific for the 2'-hydroxyl of 2',4,4'-trihydroxychalcone, with essentially no activity toward narigenin chalcone, caffeic acid, or daidzein. Kinetic analysis indicated a sequential bi bi mechanism with Km values of 2.2 and 17.7 microM for 2',4,4'-trihydroxychalcone and S-adenosyl-L-methionine, respectively. S-Adenosyl-L-homocysteine was a potent inhibitor. The chalcone OMT represents the third distinct OMT isolated from alfalfa cell cultures.