5967A randomized trial of yoga therapy for reflex syncope

Background

Reflex syncope (RS), the most common cause of syncope is usually recurrent, associated with decreased quality of life, and frustrates both the clinicians and the patients with a paucity of effective treatment options.

Purpose

To assess the effectiveness of yoga therapy on the recurrence of reflex syncope.

Methods

Subjects with recurrent RS (>3 episodes) and positive head-up tilt test were enrolled prospectively, and randomized to conventional therapy with physical maneuvres (Group 1) and yoga therapy (Group 2). Group 1 patients were taught physical counter-pressure maneuvers as per guidelines. Group 2 patients were taught yoga for 7 sessions by a certified Yoga instructor/therapist, and then advised to perform yoga for 60 minutes at least five days/week for six months. The Yoga module consisted of Pranayama (breathing techniques), Asanas (Postures) and Dhyana (Meditation) for 60 minutes/session. Both groups were followed up monthly for 6 months in the syncope clinic noting down the recurrences and the quality of life using the syncope functional status questionnaire score.

Result

The study group consisted of 97 patients (group 1: 46 patients and group 2: 51 patients) enrolled prospectively between June 2015 to February 2017. The mean age was 33.1±16.6 years, with male: female ratio 1.1:1, and a mean of 6.4±6.06 syncope episodes (group 1: 6.8±8.0 vs. group 2: 6.0±4.0; p=0.551). The mean duration of symptoms was 17.1±20.71 months (group 1: 16.1±22.8 months vs. group 2: 17.8±19.1 months; p=0.694). There was a significant decrease in the recurrences of syncope in the yoga group compared to the conventional group at three months (group 1: 1.8±1.4 vs group 2: 0.8±0.9, P<0.001) as well as six months follow-up (group 1: 3.38±3.0 vs group 2: 0.98±1.23, P<0.001). The quality of life score at 6 months improved in 20 patients in group 1 and in 45 patients in group 2 (<0.001).

Conclusion

Guided yoga therapy is superior to conventional measures in reducing the number of syncopal episodes and improves the quality of life in patients with reflex syncope. Yoga therapy should be considered as treatment strategy for patients with reflex syncope.

Photobleaching of red fluorescence in oral biofilms

BACKGROUND AND OBJECTIVE

Many species of oral bacteria can be induced to fluoresce due to the presence of endogenous porphyrins, a phenomenon that can be utilized to visualize and quantify dental plaque in the laboratory or clinical setting. However, an inevitable consequence of fluorescence is photobleaching, and the effects of this on longitudinal, quantitative analysis of dental plaque have yet to be ascertained.

MATERIAL AND METHODS

Filter membrane biofilms were grown from salivary inocula or single species (Prevotella nigrescens and Prevotella intermedia). The mature biofilms were then examined in a custom-made lighting rig comprising 405 nm light-emitting diodes capable of delivering 220 W/m(2) at the sample, an appropriate filter and a digital camera; a set-up analogous to quantitative light-induced fluorescence digital. Longitudinal sets of images were captured and processed to assess the degradation in red fluorescence over time.

RESULTS

Photobleaching was observed in all instances. The highest rates of photobleaching were observed immediately after initiation of illumination, specifically during the first minute. Relative rates of photobleaching during the first minute of exposure were 19.17, 13.72 and 3.43 arbitrary units/min for P. nigrescens biofilms, microcosm biofilm and P. intermedia biofilms, respectively.

CONCLUSION

Photobleaching could be problematic when making quantitative measurements of porphyrin fluorescence in situ. Reducing both light levels and exposure time, in combination with increased camera sensitivity, should be the default approach when undertaking analyses by quantitative light-induced fluorescence digital.

Structural characterization by x-ray methods of novel antimicrobial gallium-doped phosphate-based glasses

Antimicrobial gallium-doped phosphate-based glasses of general composition (P(2)O(5))(0.45)(CaO)(0.16)(Na(2)O)(0.39-x)(Ga(2)O(3))(x) (where x=0, 0.01, 0.03, and 0.05) have been studied using the advanced synchrotron-based techniques of Ga K-edge x-ray absorption spectroscopy and high-energy x-ray diffraction to provide a structural insight into their unique properties. The results show that the Ga(3+) ions are octahedrally coordinated. Furthermore, substitution of Na(2)O by Ga(2)O(3) strengthens the phosphate network structure because the presence of GaO(6) octahedra inhibits the migration of the remaining Na(+) ions. The results are discussed in terms of the use of Na(2)O-CaO-P(2)O(5) glasses as controlled-delivery devices for antimicrobial Ga(3+) ions in biomedical applications. We are thereby able to relate the atomic-scale environment of the Ga(3+) ions beneficially to the glass dissolution, and thus to their ability to disrupt bacterial cell activity by usurping the role of iron.

Large-scale production and efficient recovery of PHB with desirable material properties, from the newly characterised Bacillus cereus SPV

A newly characterised Bacillus strain, Bacillus cereus SPV was found to produce PHB at a concentration of 38% of its dry cell weight in shaken flask cultures, using glucose as the main carbon source. Polymer production was then scaled up to 20 L batch fermentations where 29% dry cell weight of PHB was obtained within 48 h. Following this, a simple glucose feeding strategy was developed and the cells accumulated 38% dry cell weight of PHB, an increase in the overall volumetric yield by 31% compared to the batch fermentation. Sporulation is the cause of low PHB productivity from the genus Bacillus [Wu, Q., Huang, H., Hu, G.H., Chen, J., Ho, K.P., Chen, G.Q., 2001. Production of poly-3-hydroxybutyrate by Bacillus sp. JMa5 cultivated in molasses media. Antonie van Leeuwenhoek 80, 111-118]. However, in this study, acidic pH conditions (4.5-5.8) completely suppress sporulation, in accordance with Kominek and Halvorson [Kominek, L.A., Halvorson, H.O., 1965. Metabolism of poly-beta-hydroxybutyrate and acetoin in Bacillus cereus. J. Bacteriol. 90, 1251-1259], and result in an increase in the yield of PHB production. This observation emphasises the potential of the use of Bacillus in the commercial production of PHB and other PHAs. The recovery of the PHB produced was optimised and the isolated polymer characterised to identify its material properties. The polymer extracted, was found to have similar molecular weight, polydispersity index and lower crystallinity index than others reported in literature. Also, the extracted polymer was found to have desirable material properties for potential tissue engineering applications.

Effect of ternary phosphate-based glass compositions on osteoblast and osteoblast-like proliferation, differentiation and death in vitro

There is currently a need to expand the range of graft materials available to orthopaedic surgeons. This study investigated the effect of ternary phosphate-based glass (PBG) compositions on the behaviour of osteoblast and osteoblast-like cells. PBGs of the formula (in mol.%) P(2)O(5)(50)-CaO(50-X)-Na(2)O(X), where X is either 2, 4, 6, 8 or 10, were produced and their influence on the proliferation, differentiation and death in vitro of adult human bone marrow stromal cells (hBMSCs) and human fetal osteoblast 1.19 (HFOB 1.19) cells were assessed. Tissue culture plastic (TCP) and hydroxyapatite (HA) were used as controls. Exposure to PBGs in culture inhibited cell adhesion and proliferation and increased cell death in both cell types studied. There was no significant difference in percentage cell death between the PBGs, which was significantly greater than the controls. However, compared with other PBGs, a greater number of cells were found on the 48mol.% CaO which may have been due to either increased adherence or proliferation, or both. This composition was capable of supporting osteogenic proliferation and early differentiation, and supports the notion that chemical modification of the glass could lead to a more biologically compatible substrate with the potential to support osteogenic grafting. Realisation of this potential should lead to the development of novel grafting strategies for the treatment of problematic bone defects.

Poly(3- hydroxybutyrate)/Bioglass(®) composite films containing carbon nanotubes

Poly(3hydroxybutyrate) (P(3HB))/Bioglass(®) composites incorporating multiwalled carbon nanotubes (MWCNTs) have been successfully prepared by the solvent casting technique. The microstructure, electrical properties and bioactivity of the composites were characterized using scanning electron microscopy, x-ray diffraction and current-voltage measurements. Different concentrations of MWCNTs were used to determine their effect on the electrical properties of the composites. MWCNTs and Bioglass(®) particles were found to be homogeneously dispersed throughout the P(3HB) matrix. The electrical resistance of the composite samples decreased on increasing the MWCNT concentration, as expected. An in vitro degradation study in simulated body fluid (SBF) was carried out on composite samples. The formation of hydroxyapatite on the surfaces of P(3HB)/Bioglass(®)/MWCNT composite films was confirmed after two months of immersion in SBF. This hydroxyapatite layer was not formed on the neat polymeric films and on composites containing MWCNTs only (without Bioglass(®)). It was found that the presence of MWCNTs did not hinder the bioactivity of the Bioglass(®) particles, as confirmed by SEM and XRD studies on composite samples.

Polyhydroxyalkanoate (PHA) biosynthesis from structurally unrelated carbon sources by a newly characterized Bacillus spp

A newly acquired polyhydroxyalkanoate (PHA) producing Bacillus spp. was identified to be a strain of Bacillus cereus using a range of microbiological and molecular techniques. This strain, named B. cereus SPV, was found to be capable of using a wide range of carbon sources including glucose, fructose, sucrose, various fatty acids and gluconate for the production of PHAs, an advantage for the commercial production of the polymers. The media used for the polymer production was novel in the context of the genus Bacillus. The PHA, once produced, was found to remain at a constant maximal concentration, without any degradation, a great advantage for the commercial production of the PHAs. This particular strain of Bacillus spp. was able to synthesize various PHAs with 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV) and 4-hydroxybutyrate (4HB)-like monomer units from structurally unrelated carbon sources such as fructose, sucrose and gluconate. This is the first report of the incorporation of a 4HB related monomer containing PHA by the genus Bacillus and from structurally unrelated carbon sources. The PHAs isolated had molecular weights ranging between (0.4 and 0.8) x 10(6) and low polydispersity index values (M(W)/M(N)) ranging from 2.6 to 3.4.