Bone speed of sound, biochemical markers of bone turnover and IGF-1 in competetive synchronized swimmers

The purpose of this study was to compare bone speed of sound (SOS) measured by quantitative ultrasound, circulating levels of IGF- 1 and biochemical markers of bone turnover in pre- (Pr) and post-menarcheal (Po) synchronized swimmers (SS) and controls (NS). Seventy participants were recruited: 8 PrSS, 22 PoSS, 20 PrNS, and 20 PoNS. Anthropometric measures of height, weight, skeletal maturity and percent body fat were taken, and dietary intake evaluated using 24-hour recall. Bone SOS was measured at the distal radius and mid-tibia and blood samples analyzed for IGF-1, osteocalcin, NTx, and 25-OH vitamin D. Results demonstrated maturational effects on bone SOS, IGF-1 and bone turnover (p<0.05), with no differences observed between SS and NS. Main effects were observed for a reduced caloric intake in SS compared to NS (p<0.05). Therefore, SS does not offer additive affects on bone strength but imparts no adverse affects to skeletal health in these athletes.

Effects of dietary restraint and oral contraceptives on bone strength and bone turnover in young women

ABSTRACT Introduction The purpose of this study was to assess specific osteoporosis-related health behaviours and physiological outcomes including daily calcium intake, physical activity levels, bone strength, as assessed by quantitative ultrasound, and bone turnover among women between the ages of 18 and 25. Respective differences on relevant study variables, based on dietary restraint and oral contraceptive use were also examined. Methods One hundred women (20.6 ± 0.2 years of age) volunteered to participate in the study. Informed written consent was obtained by all subjects prior to participation. The study and all related procedures were approved by the Brock University Research Ethics Board. Body mass, height, relative body fat, as well as chest, waist and hip circumferences were measured using standard procedures. The 10-item restrained eating subscale of the Dutch Eating Behaviour Questionnaire (DEBQ) was used to assess dietary restraint (van Strien et al., 1986). Daily calcium intake was assessed by the Rapid Assessment Method (RAM) (Hertzler & Frary 1994). Weekly physical activity was documented by the 4-item Godin Leisure-Time Exercise Questionnaire (Godin & Shephard 1985). Bone strength was determined from the speed of sound (SOS) as measured by QUS (Sunlight 7000S). SOS measurements (m/s) were taken of the dominant and non-dominant sides of the distal one third of the radius and the mid-shaft of the tibia. Resting blood samples were collected from all subjects between 9am and 12pm, in order to evaluate the impact of lifestyle factors on biochemical markers of bone turnover. Blood was collected during the early follicular phase of the menstrual cycle (approximately days 1-5) for all subjects. Samples were centrifliged and the serum or plasma was aliquoted into separate tubes and stored at -80°C until analysis. The bone formation markers measured were Osteocalcin (OC), bone specific alkaline phosphatase (BAP) and 25-OH vitamin D. The bone resorption markers measured were the carboxy (CTx) and amino (NTx) terminal telopeptides of type-I collagen crosslinks. All markers were assessed by ELISA. Subjects were divided into high (HDR) and low dietary restrainers (LDR) based on the median DEBQ score, and also into users (BC) and non-users (nBC) of oral contraceptives. A series of multiple one way ANOVA's were then conducted to identify differences between each set of groups for all relevant variables. A two-way ANOVA analysis was used to explore significant interactions between dietary restraint and use of oral contraceptives while a univariate follow-up analysis was also performed when appropriate. Pearson Product Moment Correlations were used to determine relationships among study variables. Results HDR had significantly higher BMI, %BF and circumference measures but lower daily calcium intake than LDR. There were no significant differences in physical activity levels between HDR and LDR. No significant differences were found between BC and nBC in body composition, calcium intake and physical activity. HDR had significantly lower tibial SOS scores than LDR in both the dominant and non-dominant sites. The post-hoc analysis showed that within the non-birth control group, the HDR had significantly lower tibial SOS scores of bone strength when compared to the LDR but Aere were no significant differences found between the two dietary restraint groups for those currently on birth control. HDR had significantly lower levels of OC than LDR and the BC group had lower levels of BAP than the nBC group. Consistently, the follow-up analysis revealed that within those not on birth control, subjects who were classified as HDR had significantly (f*<0.05) lower levels of OC when compared with LDR but no significant differences were observed in bone turnover between the two dietary restraint groups for those currently on birth control. Physical activity was not correlated with SOS scores and bone turnover markers possibly due to the low physical activity variability in this group of women. Conclusion This is the first study to examine the effects of dietary restraint on bone strength and turnover among this population of women. The most important finding of this study was that bone strength and turnover are negatively influenced by dietary restraint independent of relative body fat. In general, the results of the present thesis suggest that dietary restraint, oral contraceptive use, as well as low daily calcium intake and low physical activity levels were widespread behaviours among this population of college-aged women. The young women who were using dietary restraint as a strategy to lose weight, and thus were in the HDR group, despite their higher relative body fat and weight, had lower scores of bone strength and lower levels of markers of bone turnover compared to the low dietary restrainers. Additionally, bone turnover seemed to be negatively affected by oral contraceptives, while bone strength, as assessed by QUS, seemed unaffected by their use in this population of young women. Physical activity (weekly energy expenditure), on the other hand, was not associated with either bone strength or bone tiimover possibly due to the low variability of this variable in this population of young Canadian women.

Metabolic, biochemical and molecular profiling of Catharanthus roseus flower cultivars and transformed hairy roots for monoterpenoid indole alkaloid accumulation /

Catharanthlls rosellS (L.) G Don is a commercially significant flower species and in addition is the only source of the monoterpenoid indole alkaloids (MIA) vinblastine and vincristine, which are key pharmaceutical compounds that are used to combat a number of different cancers. Therefore, procurement of the antineoplastic agents is difficult but essential procedure. Alternatively, CatharanthllS tissue cultures have been investigated as a source of these agents; however they do not produce vindoline, which is an obligate precursor to vinblastine and vincristine. The interest in developing high MIA cultivars of Catharantlws rosellS has prompted metabolic profiling studies to determine the variability of MIA accumulation of existing flowering cultivars, with particular focus on the vindoline component ofthe pathway. Metabolic profiling studies that used high performance liquid chromatography of MIAs from seedlings and young leaf extracts from 50 different flowering cultivars showed that, except for a single low vindoline cultivar (Vinca Mediterranean DP Orchid), they all accumulate similar levels of MIAs. Further enzymatic studies with extracts from young leaves and from developing seedlings showed that the low vindoline cultivar has a IO-fold lower tabersonine-16-hydroxylase activity than those of CatharanthllS rosellS cv Little Delicata. Additionally, studies aimed at metabolic engineering ofvindoline bios}l1thesis in Catharanthus rosellS hairy root cultures have been performed by expressing the last step in vindoline biosynthesis [Dcacetylvindoline-4-0- acetyltransferase (DAT)]. Enzymatic profiling studies with transformed hairy roots have confirmed that over-expressing DAT leads to lines with high levels of O-acetyltransferase activity when compared to non-expressing hairy roots. One particular DA T over111 expressing hairy root culture (line 7) contained 200 times the OAT activity than leaves of control lines. Additional MIA analyses revealed that DAT over-expressing hairy roots have an altered alkaloid profile with significant variation in the accumulation of h6rhammericine. Further analysis of transformed hairy root line 7 suggests a correlation between the expression of OAT activity and h6rhammericine accumulation with root maturation. These studies show that metabolic and selective enzymatic profiling can enhance our ability to search for relevant MIA pathway mutants and that genetic engineering with appropriate pathway genes shows promise as a tool to modify the MIA profile of Catharanthus roseus.

A biochemical predictor of performance during mesophilic anaerobic fermentation of starch wastewater

The aim of this study was to determine the potential of biochemical parameters, such as enzyme activity and adenosine triphosphate (ATP) levels, as monitors of process performance in the Upflow Anaerobic Sludge Blanket (UASB) reactor utilizing a starch wastewater. The acid and alkaline phosphatase activity and the ATP content of the UASB sludge were measured in response to changes in flow rate and nutrient loading. Conventional parameters of process performance, such as gas production, acetic acid production, COD, phosphorus, nitrogen and suspended solids loadings and % COD removal were also monitored. The response of both biochemical and conventional parameters to changing process conditions was then compared. Alkaline phosphatase activity exhibited the highest activity over the entire study perioda A high suspended solids loading was observed to upset the system in terms of gas production, acetic acid production and % COD removala The initial rate of increase in alkaline phosphatase activity following an increase in loading was four times as great during process upset than under conditions of good performance. The change in enzyme actiVity was also more sensitive to process upset than changes in acetic acid production. The change in ATP content of the sludge with time suggested that enzyme actiVity was changing independently of the actual viable biomass present. The bacterial composition of the anaerobic sludge granules was similar to that of other sludge bed systems, at the light and scanning electron microscope level. Isolated serum bottle cultures produced several acids involved in anaerobic carbohydrate metabolism. The overall performance of the UASB system indicated that higher loadings of soluble nutrients could have been tolerated by the system.

Biochemical and histological investigations of viral localisation in the hypersensitive reaction of Phaselous vulgaris L. var Pinto to tobacco mosaic virus infection

STOBBS, Lorne,W ABSTRACT Biochemical and Histological Investigations of viral localisation in the hypersensitive reaction of Phaseolus vulgaris L. var Pinto to tobacco mosaic virus infection. The infection of Phaseolus vulgaris L. var Pinto with tobacco mosaic virus (TMV) results in the production of distinct necrotic lesions confining the virus to restricted areas of the leaf surface. Biochemical and histological changes in the leaf tissue as a result of infection have been described. Trace accumulations of fluorescent metabolites, detected prior to lesion expression represent metabolites produced, by the cell in response to virus infection. These substances, are considered to undergo oxidation and in diffusing into adjacent cells, react with cellular constituents causing the death of these cells. Such cellular necrosis in advance of infection effectively limits virus spread. Chromatographic studies on extracts from TMV infected Pinto bean leaf tissue suggests that a number of extra-fluorescent metabolites produced on lesion'expression represent end products of phenolic oxidation r,eactionsoccurring earlier in these cells. Inhibition of phenolic oxidation by ascorbate infiltration or elevated temperature treatment resulted in the absence of extra-fluorescent metabolites and the continued movement of virus in the absence of necrosis. Further studies with i ascorbate infiltration indicated that irreversible necrotic events were determined as early as 12 tci 18 hrs after viral inoculation. Histochemical tests indicated that callose formation was initiated at this time, and occurred in response to necrotisation. Inhibition of necrosis by either ascorbate infiltration or elevated temp8rature treatment resulted in the absence of callose deposition. Scanning electron'micrographs of infected tissue revealed severe epidermal and palisade cell damage. Histochemical tests indicated extensive callose formation in cells bordering the lesion, and suggested the role of callose iTh the blockage of intercellular connections limiting virus movement. The significance of these cellular changes is discussed. ii

Effect of increased milk intake combined with endurance exercise training on body composition, blood-lipids and inflammatory markers in overweight young males

Consuming low-fat milk (LFM) after resistance training leads to improvements in body composition. Habitual aerobic exercise and dairy intake are relatively easy lifestyle modifications that could benefit a population at risk for becoming obese. Thus, the purpose of this study was to investigate combining increased LFM intake with endurance exercise on body composition, blood-lipid profile and metabolic markers. 40 young males were randomized into four groups: one ingesting 750mL LFM immediately post-exercise, the other 6hrs post-exercise; and two isocaloric carbohydrate groups ingesting at the two different times. Participants completed a 12 week endurance-training program (cycling 1 hour/day at ~60%VO2peak, 5 days/week). 23 participants completed the study. Increases in lean mass (p < 0.05), and decreases in anti-inflammatory marker adiponectin (p < 0.05) were seen in all groups. No other significant changes were observed. Future analyses should focus on longer duration exercise and include a larger sample.

Bone markers and cytokines in response to low-impact, high-intensity exercise

A low-impact, high-intensity interval exercise (HIE) bout was used to determine whether an association exists between cytokines and bone turnover markers following an acute bout of exercise. Twenty-three recreationally active males (21.8±2.4yr) performed a single HIE bout on a cycle ergometer at 90% relative intensity. Venous blood samples were collected prior to exercise, 5-minutes, 1-hour, and 24-hours post-exercise, and were analyzed for serum levels of pro-inflammatory (IL-6, IL-1α, IL-1β, and TNF-α) and anti- inflammatory cytokines (IL-10) and markers of bone formation (BAP, OPG) and resorption (NTX, RANKL). Significant effects were observed with all bone markers, especially 5-minutes post-exercise with BAP, OPG, and RANKL increasing from baseline (p<0.05). Significant effects were also observed for IL-1α, IL-1β, IL-6, and TNF-α (p<0.00, p=0.04, p=0.03, p<0.00). In addition, post-exercise changes in NTX, BAP, and OPG were significantly correlated pro- and anti-inflammatory cytokines, suggesting that an interaction exists between the immune and skeletal response to exercise.

THE ACUTE EFFECTS OF A SINGLE SESSION OF PLYOMETRIC EXERCISE ON MARKERS OF BONE TURNOVER IN BOYS AND MEN

The study objective was to compare the response of bone markers to an exercise session consisting of high mechanical loading (144 jumps) between boys (n=12, 10.2 ± 0.4 years) and men (n=18, 22.5 ± 0.7 years). Blood samples were collected at pre-, 5, 60 minutes post-, and 24 hours post-exercise) to measure bone-specific alkaline phosphatase (BAP), amino-terminal cross-linking telopeptide (NTx), osteoprotegrin (OPG) and receptor activator of nuclear factor kb ligand (RANKL). Boys had higher BAP levels at all time points, with an increase 24 hours post-exercise. No such increase was observed in men. Likewise, NTx levels were higher in boys, with a greater increase over time than in men. OPG and RANKL levels were similar in boys and men at all times. In summary, even one session of exercise stimulates bone turnover, as reflected in the increase in both BAP and NTx, in boys (but not men) within 24 hours.

Chemical, biochemical, and molecular characterization of a low vindoline Catharanthus roseus mutant.

The Madagascar periwinkle (Catharanthus roseus) is the sole source of the anticancer drug vinblastine, which is formed via the coupling of monoterpenoid indole alkaloids (MIAs) catharanthine and vindoline. A mutant line of C. roseus (M2-1865) with an altered MIA profile was identified in a screen of 4000 M2 lines generated by ethylmethanesulfonate (EMS) chemical mutagenesis. While this line did not accumulate vinblastine due to reduced levels of vindoline within the leaves, significant levels of 2,3-epoxide derivatives of tabersonine accumulated on the leaf surface. Detailed nucleotide, amino acid, and enzyme activity analyses of tabersonine 3-reductase in the M2-1865 line showed that a single amino acid substitution (H189Y) diminished the biochemical activity of T3R by 95%. Genetic crosses showed the phenotype to be recessive, exhibiting standard Mendelian single-gene inheritance. The usefulness of EMS mutagenesis in elucidating MIA biosynthesis is highlighted by the results of this study.