Virtual urgent care is here to stay: driving toward safe, equitable, and sustainable integration within emergency medicine.

BACKGROUND: Virtual care in Canada rapidly expanded during the COVID-19 pandemic in a low-rules environment in response to pressing needs for ongoing access to care amid public health restrictions. Emergency medicine specialists now face the challenge of advising on which virtual urgent care services ought to remain as part of comprehensive emergency care. Consideration must be given to safe, quality, and appropriate care as well as issues of equitable access, public demand, and sustainability (financial and otherwise). The aim of this project was to summarize current literature and expert opinion and formulate recommendations on the path forward for virtual care in emergency medicine. METHODS: We formed a working group of emergency medicine physicians from across Canada working in a variety of practice settings. The virtual care working group conducted a scoping review of the literature and met monthly to discuss themes and develop recommendations. The final recommendations were circulated to stakeholders for input and subsequently presented at the 2023 Canadian Association of Emergency Physicians (CAEP) Academic Symposium for discussion, feedback, and refinement. RESULTS: The working group developed and reached unanimity on nine recommendations addressing the themes of system design, equity and accessibility, quality and patient safety, education and curriculum, financial models, and sustainability of virtual urgent care services in Canada. CONCLUSION: Virtual urgent care has become an established service in the Canadian health care system. Emergency medicine specialists are uniquely suited to provide leadership and guidance on the optimal delivery of these services to enhance and complement emergency care in Canada.

RéSUMé: CONTEXTE: Les soins virtuels au Canada ont rapidement pris de l'ampleur pendant la pandémie de COVID-19 dans un environnement où les règles sont peu strictes, en réponse aux besoins urgents d'accès continu aux soins dans un contexte de restrictions en santé publique. Les spécialistes de la médecine d'urgence sont maintenant confrontés au défi de conseiller sur les services de soins d'urgence virtuels qui devraient rester dans le cadre des soins d'urgence complets. Il faut tenir compte des soins sécuritaires, de qualité et appropriés, ainsi que des questions d'accès équitable, de la demande publique et de la durabilité (financière et autre). L'objectif de ce projet était de résumer la littérature actuelle et l'opinion d'experts et de formuler des recommandations sur la voie à suivre pour les soins virtuels en médecine d'urgence. MéTHODES: Nous avons formé un groupe de travail composé de médecins urgentistes de partout au Canada qui travaillent dans divers milieux de pratique. Le groupe de travail sur les soins virtuels a effectué un examen de la portée de la documentation et s'est réuni chaque mois pour discuter des thèmes et formuler des recommandations. Les recommandations finales ont été distribuées aux intervenants pour obtenir leurs commentaires, puis présentées au symposium universitaire 2023 de l'Association canadienne des médecins d'urgence (ACMU) pour discussion, rétroaction et perfectionnement. RéSULTATS: Le groupe de travail a élaboré et atteint l'unanimité sur neuf recommandations portant sur les thèmes de la conception du système, de l'équité et de l'accessibilité, de la qualité et de la sécurité des patients, de l'éducation et des programmes, des modèles financiers et de la viabilité des services virtuels de soins d'urgence au Canada. CONCLUSION : Les soins d'urgence virtuels sont devenus un service établi dans le système de santé canadien. Les spécialistes en médecine d'urgence sont particulièrement bien placés pour fournir un leadership et des conseils sur la prestation optimale de ces services afin d'améliorer et de compléter les soins d'urgence au Canada.

Life cycle assessment (LCA) of electrically-enhanced POME filtration: Environmental impacts of conductive-membrane formulation and process operating parameters.

This study assessed the environmental impacts of the formulation of graphene oxide (GO)/multi-walled carbon nanotubes (MWCNTs) conductive membranes and of the process operating parameters of electrically-enhanced palm oil mill effluent (POME) filtration. Two different analyses approaches were employed, cradle-to-gate approach for conductive membrane production and gate-to-gate approach for the POME filtration process. The parameters in conductive-membrane formulation (e.g. the weight ratio of carbon nanomaterials, and concentration of GO/MWCNT nanohybrids) and process operating parameters (e.g. electric field strength and electricity operating mode) were investigated. The findings herein are twofold. Firstly, for the fabrication of GO/MWCNT conductive membranes, the best weight ratio of GO:MWCNTs was found to be 1:9, given its superior membrane electrical conductivity with lower environmental impacts by 8.51% compared to pristine MWCNTs. The most suitable concentration of carbon nanomaterials was found to be 5 wt%, given its lowest impacts on resource depletion, human health, and ecosystems. Secondly, for the electrically-enhanced POME filtration, the optimum process operating parameters were found to be the application of an electric field of 300 V/cm in the continuous mode, given its lower environmental impacts (22.99%-89.30%) secondary to its requirement of the least electricity to produce permeate. The present study has established not only the optimized conditions in membrane formulation but also the operating parameters of electrically-enhanced filtration; such findings enable the use of cleaner production and sustainable approach to minimize fouling for industrial applications, whilst maintaining excellent efficiency.

Promoting physical activity among children with cancer through an integrated experiential training programme with coaching: A qualitative study.

OBJECTIVE: The study aim was to investigate how the integrated experiential training programme with coaching could motivate children undergoing cancer treatment to adopt and maintain physical activity. METHODS: A descriptive phenomenological approach was used. A purposive sample of 23 children and their parents participated in one-to-one 25-30-minute semistructured interviews. Interviews were tape-recorded and transcribed. Colaizzi's method of descriptive phenomenological data analysis was used. RESULTS: The integrated programme motivated children with cancer by increasing children's and parents' knowledge of physical activity, enhancing confidence in physical activity and improving physical and psychological well-being. Moreover, the programme provided children with encouragement and psychological support through coach companionship. The programme also facilitated children's participation in physical activity and modified perceptions of physical activity. CONCLUSION: This study addressed a gap in the literature by exploring how an integrated programme promoted and maintained physical activity in childhood cancer patients. PRACTICE IMPLICATIONS: The integrated experiential training programme is feasible and can be easily sustained. Future studies could extend the programme beyond aspects of physical activity to help people change their health practices and maintain a healthy lifestyle.

An integrated experiential training programme with coaching to promote physical activity, and reduce fatigue among children with cancer: A randomised controlled trial.

OBJECTIVE: This study examined the effectiveness of an integrated programme in promoting physical activity, reducing fatigue, enhancing physical activity self-efficacy, muscle strength and quality of life among Chinese children with cancer. METHODS: A randomised controlled trial was conducted in a Hong Kong public hospital. Seventy eligible children were randomly assigned to an experimental group (n = 37) or a control group (n = 33). The experimental group received an integrated programme with 28 home visits from coaches over a 6-month period. The control group received a placebo intervention. The primary outcome was fatigue at 9 months (3 months after intervention completion). Secondary outcomes were physical activity levels, physical activity self-efficacy, muscle strength and quality of life at 9 months, assessed at baseline, and 6 and 9 months after starting the intervention. RESULTS: The experimental group reported significantly lower levels of cancer-related fatigue, higher levels of physical activity and physical activity self-efficacy, greater right- and left-hand grip strength and better quality of life than the control group at 9 months. CONCLUSION: The programme is effective and feasible to implement among children with cancer and offers an alternative means of ameliorating the healthcare burden. PRACTICE IMPLICATIONS: Healthcare professionals should build multidisciplinary partnerships to sustain such programmes.

Evaluation of biological, psychosocial, and interventional predictors for success of a smoking cessation programme in Hong Kong.

INTRODUCTION: Predictors for smoking cessation have been identified in different studies but some of the predictors have been variable and inconsistent. In this study, we reviewed all the potential variables including medication, counselling, and others not commonly studied to identify the robust predictors of smoking cessation. METHODS: This historical cohort study was conducted in smoking cessation clinics in Hong Kong. Subjects who volunteered to come for free treatment between January 2010 and December 2011 were reviewed. Those under the age of 18 years, or who were mentally unstable or cognitively impaired were excluded. Counselling and quit-smoking medications were provided to the participants. The outcome measure was self-reported 7-day point prevalence abstinence rate at week 26. RESULTS: Univariate analysis showed that the following were significant predictors of quitting: (1) psychosocial variables such as feeling stressed, feeling depressed, confidence in quitting, difficulty in quitting, importance of quitting, Smoking Self-Efficacy Questionnaire score; (2) smoking-related variables such as number of cigarettes smoked per day, Fagerström Test for Nicotine Dependence score, number of high-risk situations encountered; (3) health-related variable of having mental illness; (4) basic demographics such as age, marital status, and household income; and (5) interventional variables such as counselling and pharmacotherapy. Multiple logistic regression showed that the independent predictors were age, having mental illness, daily cigarette consumption, Fagerström Test for Nicotine Dependence score, reasons for quitting, confidence in quitting, depressed mood, external self-efficacy, intervention with counselling and medications. CONCLUSIONS: This clinic-based local study offers a different perspective on the predictors of quitting. It reminds us to adopt a holistic approach to deal with nicotine withdrawal, to enhance external self-efficacy to resist temptation and social influences, to provide adequate counselling, and to help smokers to cope with mood problems.

Effects of a green tea extract, Polyphenon E, on systemic biomarkers of growth factor signalling in women with hormone receptor-negative breast cancer.

BACKGROUND: Observational and experimental data support a potential breast cancer chemopreventive effect of green tea. METHODS: We conducted an ancillary study using archived blood/urine from a phase IB randomised, placebo-controlled dose escalation trial of an oral green tea extract, Polyphenon E (Poly E), in breast cancer patients. Using an adaptive trial design, women with stage I-III breast cancer who completed adjuvant treatment were randomised to Poly E 400 mg (n = 16), 600 mg (n = 11) and 800 mg (n = 3) twice daily or matching placebo (n = 10) for 6 months. Blood and urine collection occurred at baseline, and at 2, 4 and 6 months. Biological endpoints included growth factor [serum hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF)], lipid (serum cholesterol, triglycerides), oxidative damage and inflammatory biomarkers. RESULTS: From July 2007-August 2009, 40 women were enrolled and 34 (26 Poly E, eight placebo) were evaluable for biomarker endpoints. At 2 months, the Poly E group (all dose levels combined) compared to placebo had a significant decrease in mean serum HGF levels (-12.7% versus +6.3%, P = 0.04). This trend persisted at 4 and 6 months but was no longer statistically significant. For the Poly E group, serum VEGF decreased by 11.5% at 2 months (P = 0.02) and 13.9% at 4 months (P = 0.05) but did not differ compared to placebo. At 2 months, there was a trend toward a decrease in serum cholesterol with Poly E (P = 0.08). No significant differences were observed for other biomarkers. CONCLUSIONS: Our findings suggest potential mechanistic actions of tea polyphenols in growth factor signalling, angiogenesis and lipid metabolism.

Evaluation of PCR for the diagnosis of dermatophytes in nail specimens from patients with suspected onychomycosis.

BACKGROUND: Conventional methods for detecting fungi in nail specimens are either nonspecific (microscopy) or insensitive (culture). Recently, PCR has been used to improve sensitivity in detecting the causative fungi in nail specimens from patients with suspected onychomycosis. AIM: To compare the detection rates of PCR with those of microscopy (with potassium hydroxide; KOH) and culture for dermatophytes in nail specimens from patients with suspected onychomycosis. METHODS: In total, 120 patients with clinically suspected onychomycosis were recruited, and using a topoisomerase II-based PCR, we compared the detection rate of dermatophytes for the three methods. RESULTS: KOH microscopy, culture and PCR respectively yielded positive rates of 35 (29.2%), 12 (10%) and 48 (40%), and negative rates of 85 (70.8%), 108 (90%) and 72 (60%). Two culture-positive specimens were not detected by PCR, but PCR picked up 38 specimens missed by culture. Of the 35 specimens that were microscopy-positive, 12 grew dermatophytes and 23 nondermatophytes. CONCLUSIONS: This study demonstrates that PCR has a higher positive and lower negative rate for detection of dermatophytes compared with KOH microscopy or culture. We suggest that PCR should be used as a complementary method for confirmation of clinically suspected dermatophytic onychomycosis.

Prevalence of vitamin deficiencies on admission: relationship to hospital mortality in critically ill patients.

Vitamin deficiency is believed to be common in critical illness. Water soluble and antioxidant vitamins are those most frequently used for supplementation in these patients. There are no data to confirm the prevalence of vitamin deficiencies in high-risk emergently admitted intensive care patients, nor their association with hospital mortality. One hundred and twenty-nine consecutive, critically ill patients who were emergently admitted to intensive care were enrolled in this prospective observational cohort study. Patient data including diagnosis, source of admission and severity of illness scores were prospectively collected. Within the first 48 hours of admission, concentrations of C-reactive protein, Vitamins A, E, B1, B12 and folate were measured on arterial blood. Multivariate stepwise logistic regression modelling was performed to examine the association of vitamin concentrations with hospital mortality. Fifty-five patients (43%) had a biochemical deficiency of one of the five vitamins on admission to the intensive care unit. A total of 18 patients died (14%) during their hospital stay (15 of those in the intensive care unit). Moderate correlations with C-reactive protein concentrations were demonstrated for Vitamins B12, A and E (Spearman's r = 0.309, -0.541 and -0.299, P = 0.001, 0.001 and 0.007 respectively). Hospital mortality was significantly associated with age, APACHE II score, admission and maximum Sequential Organ Failure Assessment scores and admission source in the univariate analyses. Multivariate analysis did not demonstrate an association between biochemical deficiency and mortality. Biochemical deficiencies of water-soluble and antioxidant vitamins are common on admission in unplanned or emergency admissions to the intensive care unit, but we could not demonstrate an independent association with hospital mortality.

Modality of physical exercise and cognitive function in Hong Kong older Chinese community.

OBJECTIVE: We reported the association between modality of Physical Exercise and cognitive function in 782 older Chinese adults assessed in the second phase of a population survey for dementia in Hong Kong. METHODS: Profiles of physical exercise was measured by a questionnaire (no exercise, stretching, aerobic and mind-body exercise). Cognitive Assessments included the CMMSE, ADAS-Cog, and Category Verbal Fluency Test (CVFT). RESULTS: The aerobic and mind body exercise groups with longer exercise habits (>5 years) had higher scores in most cognitive tests (Kruskal Wallis tests, p < 0.01). Beneficial effects were more significant in the young old group from 65- 75 years. CONCLUSIONS: Possible age related specific effects of aerobic and mind body exercise on cognitive reserve are worthy of further exploration.

Ceftibuten resistance and treatment failure of Neisseria gonorrhoeae infection.

Neisseria gonorrhoeae infections have been empirically treated in Hong Kong with a single oral 400-mg dose of ceftibuten since 1997. Following anecdotal reports of the treatment failure of gonorrhea with oral extended-spectrum cephalosporins, the current study was undertaken to determine the antimicrobial susceptibility pattern and molecular characteristics of isolates of N. gonorrhoeae among patients with putative treatment failure in a sexually transmitted disease clinic setting. Between October 2006 and August 2007, 44 isolates of N. gonorrhoeae were studied from patients identified clinically to have treatment failure with empirical ceftibuten. The ceftibuten MICs for three strains were found to have been 8 mg/liter. These strains were determined by N. gonorrhoeae multiantigen sequence typing to belong to sequence type 835 (ST835) or the closely related ST2469. The testing of an additional eight archived ST835 strains revealed similarly elevated ceftibuten MICs. The penA gene sequences of these 11 isolates all had the mosaic pattern previously described as pattern X. Of note is that the ceftriaxone susceptibility results of these strains all fell within the susceptible range. It is concluded that ceftibuten resistance may contribute to the empirical treatment failure of gonorrhea caused by strains harboring the mosaic penA gene, which confers reduced susceptibility to oral extended-spectrum cephalosporins. Screening for such resistance in the routine clinical laboratory may be undertaken by the disk diffusion test. The continued monitoring of antimicrobial resistance and molecular characteristics of N. gonorrhoeae isolates is important to ensure that control and prevention strategies remain effective.

Asia Pacific consensus recommendations for colorectal cancer screening.

Colorectal cancer (CRC) is rapidly increasing in Asia, but screening guidelines are lacking. Through reviewing the literature and regional data, and using the modified Delphi process, the Asia Pacific Working Group on Colorectal Cancer and international experts launch consensus recommendations aiming to improve the awareness of healthcare providers of the changing epidemiology and screening tests available. The incidence, anatomical distribution and mortality of CRC among Asian populations are not different compared with Western countries. There is a trend of proximal migration of colonic polyps. Flat or depressed lesions are not uncommon. Screening for CRC should be started at the age of 50 years. Male gender, smoking, obesity and family history are risk factors for colorectal neoplasia. Faecal occult blood test (FOBT, guaiac-based and immunochemical tests), flexible sigmoidoscopy and colonoscopy are recommended for CRC screening. Double-contrast barium enema and CT colonography are not preferred. In resource-limited countries, FOBT is the first choice for CRC screening. Polyps 5-9 mm in diameter should be removed endoscopically and, following a negative colonoscopy, a repeat examination should be performed in 10 years. Screening for CRC should be a national health priority in most Asian countries. Studies on barriers to CRC screening, education for the public and engagement of primary care physicians should be undertaken. There is no consensus on whether nurses should be trained to perform endoscopic procedures for screening of colorectal neoplasia.

Improving rock phosphate availability through feeding, mixing and processing with composting manure.

The objective of this study was to improve the availability of phosphorus (P) from rock phosphate (RP) through feeding, mixing and composting manure. The experiment was conducted as a 3 x 2 split-plot design. Manure was collected from 12 Boran steers (200+/-4.5 kg live weight) fed a basal diet of Napier grass (Pennisetum purpureum) at 2.5% body weight on a dry matter (DM) basis. The main plot treatments were (i) manure from steers supplemented with 113 g Busumbu rock phosphate (BRP) per day (FBRP), (ii) manure from steers not supplemented with BRP, feces mixed with 113 g BRP per day (MBRP) and (iii) manure from steers not supplemented with BRP and feces not mixed with BRP (CONT). The sub-plots comprised composting the manure either (i) mixed with 440 g of wheat (Triticum aestivum L.) straw per kg fresh feces (WS) or (ii) without straw (WOS). The manure was composted in 200 L plastic bins for 90 days. After 90 days, P availability was evaluated (i) by aerobic laboratory incubation at 25 degrees C for 1, 2, 4, 8, 12, and 16 weeks and (ii) by greenhouse agronomic evaluation study using maize (Zea Mays L.) as the test crop in either a humic Nitosol or an Andosol. In the laboratory incubation study, resin P was higher (p<0.05) for the WS compost than for the WOS compost; values were higher (p<0.05) for the Andosol than for Nitosol and followed the order of FBRP-WS, Andosol>FBRP-WS, Nitosol>MBRP-WS, Andosol>MBRP-WS, Nitosol>FBRP-WOS, Andosol>FBRP-WOS, Nitosol. In the greenhouse evaluation, maize crops in the WS compost had higher (p<0.05) biomass yield than the reference fertilizer, triple super phosphate, (173% versus 196%; Andosol and Nitosol, respectively). The biomass yield and P uptake relative agronomic effectiveness (RAE) for WS compost was also higher (p<0.05) than that of WOS compost (184 versus 3+/-0.8 and 242 versus 162+/-0.2, WS and WOS, biomass yield and P uptake, respectively). Nitosol biomass yield and P uptake RAE were also higher (p<0.05) than for the Andosol (99 versus 88+/-0.8 and 332 versus 72+/-0.2, Nitosol and Andosol, biomass yield and P uptake, respectively). The results show that P-enriched composting in the presence of wheat straw significantly increased P availability and increased plant growth. However, in terms of plant growth, there was no additional benefit of first feeding the RP to steers before composting the manure because most of the RP fed seem to have been utilized by the animal.

Prospective randomized crossover trial comparing fibre with lactulose in the treatment of idiopathic chronic constipation.

BACKGROUND: Fibre is often recommended as the first-choice treatment but its effects can be uneven. The aim of the study was to compare the clinical efficacy and tolerability of fibre versus lactulose in outpatients with chronic constipation. METHODS: In a prospective randomized crossover trial, patients were randomized to receive fibre or lactulose for four weeks. Between treatments, patients had at least one week free of laxatives. RESULTS: 50 patients, of median age 50 years (range, 18-85) were recruited and 39 patients completed the trial. Compared to fibre, lactulose resulted in significantly higher mean bowel frequency (7.3, 95% CI 5.7 to 8.9 vs. 5.5, 95% CI 4.4 to 6.5; p=0.001) and stool consistency score (3.4, 95% CI 3.1 to 3.7 vs. 2.9, 95% CI 2.5 to 3.3; p=0.018). Scores for ease of evacuation were similar. The frequencies of adverse effects were not significantly different, but greater in the lactulose group. Mean patients' recorded improvement score was significantly higher after taking lactulose than fibre (6.2, 95% CI 5.5 to 7.0 vs. 4.8, 95% CI 4.0 to 5.9; p=0.017). Of the 39 patients who completed the trial, 24 (61.5%) preferred lactulose and 14 (35.9%) preferred fibre. CONCLUSIONS: Lactulose had better efficacy than fibre for chronic constipation in ambulant patients, although both treatments were equally well tolerated in terms of adverse effects.

Randomized clinical trial comparing oral nifedipine with lateral anal sphincterotomy and tailored sphincterotomy in the treatment of chronic anal fissure.

BACKGROUND: The conventional treatment of chronic anal fissure is lateral sphincterotomy (LAS). The alternative options of tailored sphincterotomy (TS) and 'chemical sphincterotomy' using medication such as nifedipine have recently become available. METHODS: A prospective randomized trial was conducted to compare LAS with TS and oral nifedipine. The main endpoints were fissure healing, symptom relief, recurrence and continence. RESULTS: One hundred and thirty-two patients were treated and followed up for 4 months. LAS was significantly more effective than TS in providing pain relief (P = 0.004) and better patient satisfaction (P = 0.020) at 4 weeks. Surgery (LAS and TS) was associated with significantly better fissure healing rates (both P < 0.001 at 16 weeks) and less recurrence (both P = 0.003) than nifedipine. There were substantial problems with compliance in the nifedipine group (17 of 41 patients), related to side-effects and slow healing. There were no differences in continence between the three treatment groups. CONCLUSION: LAS was most effective in providing pain relief and allowing rapid fissure healing, with minimal recurrence and no increased risk of incontinence, in patients with good anal sphincter function.

Dynamic graciloplasty for total anorectal reconstruction after abdominoperineal resection for rectal tumour.

AIM: To review the results of dynamic graciloplasty for total anorectal reconstruction after abdominoperineal resection (APR) for rectal cancer. PATIENTS AND METHODS: Chart reviews were done on 17 patients who had dynamic graciloplasty following abdominoperineal resection and details of post-operative complications, bowel functions and recurrences were obtained. RESULTS: Seventeen patients (12 males) had dynamic graciloplasty after APR for low rectal tumours. The median age was 58.5 years (range 33-78). Three patients from overseas were lost to follow-up, and three still have not had the defunctioning stoma closed. Only 11 patients were available for evaluation of function. The median time from graciloplasty to continence to solids and liquids is 15.7 months (range 0.4-21.9 months). Six patients had defecatory problems, requiring daily irrigation to evacuate. Nine patients were continent without need for gracilis stimulation. Only two patients needed gracilis stimulation to maintain continence. Fifty percent of rectal carcinoma patients had developed a recurrence. CONCLUSION: Dynamic graciloplasty had a high morbidity and did not always bring about normal defecatory function. Gracilis stimulation was not needed to achieve continence in all cases. Conversely, dynamic graciloplasty may lead to defecatory difficulties in a large number of patients. Graciloplasty should only be considered three years after the initial APR to avoid performing the procedure in a patient who may develop recurrence as well as to select patients who are psychologically prepared for the surgery and its complications.

Novel PCL-based honeycomb scaffolds as drug delivery systems for rhBMP-2.

This study investigated a novel drug delivery system (DDS), consisting of polycaprolactone (PCL) or polycaprolactone 20% tricalcium phosphate (PCL-TCP) biodegradable scaffolds, fibrin Tisseel sealant and recombinant bone morphogenetic protein-2 (rhBMP-2) for bone regeneration. PCL and PCL-TCP-fibrin composites displayed a loading efficiency of 70% and 43%, respectively. Fluorescence and scanning electron microscopy revealed sparse clumps of rhBMP-2 particles, non-uniformly distributed on the rods' surface of PCL-fibrin composites. In contrast, individual rhBMP-2 particles were evident and uniformly distributed on the rods' surface of the PCL-TCP-fibrin composites. PCL-fibrin composites loaded with 10 and 20 microg/ml rhBMP-2 demonstrated a triphasic release profile as quantified by an enzyme-linked immunosorbent assay (ELISA). This consisted of burst releases at 2 h, and days 7 and 16. A biphasic release profile was observed for PCL-TCP-fibrin composites loaded with 10 microg/ml rhBMP-2, consisting of burst releases at 2 h and day 14. PCL-TCP-fibrin composites loaded with 20 microg/ml rhBMP-2 showed a tri-phasic release profile, consisting of burst releases at 2 h, and days 10 and 21. We conclude that the addition of TCP caused a delay in rhBMP-2 release. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and alkaline phosphatase assay verified the stability and bioactivity of eluted rhBMP-2 at all time points.

Ultrasound-induced physiological effects and secondary metabolite (saponin) production in Panax ginseng cell cultures.

This work was aimed at the effects of ultrasound (US) on the growth and secondary metabolite biosynthesis of cultured plant cells. Suspension cultures of Panax ginseng cells were exposed to US at power density below 82 mW/cm3 for short periods of time (1-4 min) in a US bath (38.5-kHz fixed frequency and 810 W maximum peak power). Under most exposure conditions, US stimulated the biosynthesis of secondary metabolites, the ginsenoside saponins of ginseng cells, increasing the total saponin content of the cell by up to 75%. The growth and viability of ginseng cells were usually depressed immediately after the exposure to US, but recovered gradually to levels similar to those of a normal culture in a few days, with virtually no net loss of biomass yield at the end of the culture period. At some lower US doses, sonicated cultures could even reach slightly higher biomass yields than that of normal cultures. The effects of US on cell growth and secondary metabolite yield showed a significant correlation with the total US energy emitted (i.e., the product of US power and exposure time). Mechanical stress and microstreaming induced by acoustic cavitation were considered as the most possible causes of the various physiological effects of US on ginseng cells. In particular, the stimulation of secondary metabolite production by US may be a result of US-induced plant cell defense response.

Antimicrobial activity of honokiol and magnolol isolated from Magnolia officinalis.

The antimicrobial activity of honokiol and magnolol, the main constituents of Magnolia officinalis was investigated. The antimicrobial activity was assayed by the agar dilution method using brain heart infusion medium and the minimum inhibitory concentration (MIC) were determined for each compound using a twofold serial dilution assay. The results showed that honokiol and magnolol have a marked antimicrobial effect (MIC = 25 microg/mL) against Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Micrococcus luteus and Bacillus subtilis, but did not show antimicrobial activity (MIC > or = 100 microg/mL) for Shigella flexneii, Staphylococcus epidermidis, Enterobacter aerogenes, Proteus vulgaris, Escherichia coli and Pseudomonas aeruginosa. Our results indicate that honokiol and magnolol, although less potent than tetracycline, show a significant antimicrobial activity for periodontal pathogens. Hence we suggest that honokiol and magnolol might have the potential to be an adjunct in the treatment of periodontitis.