Alendronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women

BACKGROUND

Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Alendronate belongs to the bisphosphonate class of drugs, which act to inhibit bone resorption by interfering with the activity of osteoclasts.

OBJECTIVES

To assess the efficacy of alendronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007.

SELECTION CRITERIA

Women receiving at least one year of alendronate, for postmenopausal osteoporosis, were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence.

DATA COLLECTION AND ANALYSIS

We undertook study selection and data abstraction in duplicate. We performed meta-analysis of fracture outcomes using relative risks and a > 15% relative change was considered clinically important. We assessed study quality through reporting of allocation concealment, blinding and withdrawals.

MAIN RESULTS

Eleven trials representing 12,068 women were included in the review. Relative (RRR) and absolute (ARR) risk reductions for the 10 mg dose were as follows. For vertebral fractures, a significant 45% RRR was found (RR 0.55, 95% CI 0.45 to 0.67). This was significant for both primary prevention, with 45% RRR (RR 0.55, 95% CI 0.38 to 0.80) and 2% ARR, and secondary prevention with 45% RRR (RR 0.55, 95% CI 0.43 to 0.69) and 6% ARR. For non-vertebral fractures, a significant 16% RRR was found (RR 0.84, 95% CI 0.74 to 0.94). This was significant for secondary prevention, with 23% RRR (RR 0.77, 95% CI 0.64 to 0.92) and 2% ARR, but not for primary prevention (RR 0.89, 95% CI 0.76 to 1.04). There was a significant 40% RRR in hip fractures (RR 0.60, 95% CI 0.40 to 0.92), but only secondary prevention was significant with 53% RRR (RR 0.47, 95% CI 0.26 to 0.85) and 1% ARR. The only significance found for wrist was in secondary prevention, with a 50% RRR (RR 0.50 95% CI 0.34 to 0.73) and 2% ARR. For adverse events, we found no statistically significant differences in any included study. However, observational data raise concerns regarding potential risk for upper gastrointestinal injury and, less commonly, osteonecrosis of the jaw.

AUTHORS' CONCLUSIONS

At 10 mg per day, both clinically important and statistically significant reductions in vertebral, non-vertebral, hip and wrist fractures were observed for secondary prevention ('gold' level evidence, www.cochranemsk.org). We found no statistically significant results for primary prevention, with the exception of vertebral fractures, for which the reduction was clinically important ('gold' level evidence).

Alendronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women

BACKGROUND

Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Alendronate belongs to the bisphosphonate class of drugs, which act to inhibit bone resorption by interfering with the activity of osteoclasts.

OBJECTIVES

To assess the efficacy of alendronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007.

SELECTION CRITERIA

Women receiving at least one year of alendronate, for postmenopausal osteoporosis, were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence.

DATA COLLECTION AND ANALYSIS

We undertook study selection and data abstraction in duplicate. We performed meta-analysis of fracture outcomes using relative risks and a > 15% relative change was considered clinically important. We assessed study quality through reporting of allocation concealment, blinding and withdrawals.

MAIN RESULTS

Eleven trials representing 12,068 women were included in the review. Relative (RRR) and absolute (ARR) risk reductions for the 10 mg dose were as follows. For vertebral fractures, a significant 45% RRR was found (RR 0.55, 95% CI 0.45 to 0.67). This was significant for both primary prevention, with 45% RRR (RR 0.55, 95% CI 0.38 to 0.80) and 2% ARR, and secondary prevention with 45% RRR (RR 0.55, 95% CI 0.43 to 0.69) and 6% ARR. For non-vertebral fractures, a significant 16% RRR was found (RR 0.84, 95% CI 0.74 to 0.94). This was significant for secondary prevention, with 23% RRR (RR 0.77, 95% CI 0.64 to 0.92) and 2% ARR, but not for primary prevention (RR 0.89, 95% CI 0.76 to 1.04). There was a significant 40% RRR in hip fractures (RR 0.60, 95% CI 0.40 to 0.92), but only secondary prevention was significant with 53% RRR (RR 0.47, 95% CI 0.26 to 0.85) and 1% ARR. The only significance found for wrist was in secondary prevention, with a 50% RRR (RR 0.50 95% CI 0.34 to 0.73) and 2% ARR. For adverse events, we found no statistically significant differences in any included study. However, observational data raise concerns regarding potential risk for upper gastrointestinal injury and, less commonly, osteonecrosis of the jaw.

AUTHORS' CONCLUSIONS

At 10 mg per day, both clinically important and statistically significant reductions in vertebral, non-vertebral, hip and wrist fractures were observed for secondary prevention ('gold' level evidence, www.cochranemsk.org). We found no statistically significant results for primary prevention, with the exception of vertebral fractures, for which the reduction was clinically important ('gold' level evidence).

Etidronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women

BACKGROUND

Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Etidronate belongs to the bisphosphonate class of drugs which act to inhibit bone resorption by interfering with the activity of osteoclasts.

OBJECTIVES

To assess the efficacy of etidronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007.

SELECTION CRITERIA

Women receiving at least one year of etidronate for postmenopausal osteoporosis were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence.

DATA COLLECTION AND ANALYSIS

Study selection and data abstraction was done in duplicate. Meta-analysis of fracture outcomes was performed with data presented as relative risks and a relative change greater than 15% was considered clinically important. Study quality was assessed through the reporting of allocation concealment, blinding and withdrawals.

MAIN RESULTS

Eleven studies representing a total of 1248 patients were included in the review.A significant 41% relative risk reduction (RRR) in vertebral fractures across eight studies (RR 0.59, 95% CI 0.36 to 0.96) was found. The six secondary prevention trials demonstrated a significant RRR of 47% in vertebral fractures (RR 0.53, 95% CI 0.32 to 0.87) and a 5% absolute risk reduction (ARR); compared with the pooled result for the two primary prevention trials (RR 3.03, 95% CI 0.32 to 28.44), which was not significant. There were no statistically significant risk reductions for non-vertebral (RR 0.98, 95% CI 0.68 to 1.42), hip (RR 1.20, 95% CI 0.37 to 3.88) or wrist fractures (RR 0.87, 95% CI: 0.32 to 2.36). For adverse events, no statistically significant differences were found in the included studies. However, observational data has led to concerns regarding potential risk for upper gastrointestinal injury.

AUTHORS' CONCLUSIONS

Etidronate, at 400 mg per day, demonstrated a statistically significant and clinically important benefit in the secondary prevention of vertebral fractures. No statistically significant reductions in vertebral fractures were observed when it was used for primary prevention. In addition, no statistically significant reductions in non-vertebral, hip, or wrist fractures were found, regardless of whether etidronate was used for primary or secondary prevention. The level of evidence for all outcomes is Silver (www.cochranemsk.org.).

WITHDRAWN: Calcium supplementation on bone loss in postmenopausal women

BACKGROUND

Although calcium is one the simplest and least expensive strategies for preventing osteoporotic fractures calcium supplementation is nevertheless not without controversy (Kanis 1989; Nordin 1990). The Food and Drug Administration in the US has permitted a bone health claim for calcium-rich foods, and the NIH in its Consensus Development Process approved a statement that high calcium intake reduces the risk of osteoporosis.

OBJECTIVES

To assess the effects of calcium on bone density and fractures in postmenopausal women.

SEARCH STRATEGY

We searched Cochrane Controlled Register, MEDLINE and EMBASE up to 2001, and examined citations of relevant articles and proceedings of international meetings.

SELECTION CRITERIA

Trials that randomized postmenopausal women to calcium supplementation or usual calcium intake in the diet and reported bone mineral density of the total body, vertebral spine, hip, or forearm or recorded the number of fractures, and followed patients for at least one year were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Three independent reviewers assessed the methodologic quality and extracted data for each trial. For each bone density site (lumbar spine, total body, combined hip and combined forearm), we calculated the weighted mean difference in bone density between treatment and control groups using the percentage change from baseline. We constructed regression models in which the independent variables were year and dose, and the dependent variable was the effect size. This regression was used to determine the years across which pooling was appropriate. Heterogeneity was assessed. For each fracture analysis we calculated a risk ratio.

MAIN RESULTS

Fifteen trials, representing 1806 participants, were included. Calcium was more effective than placebo in reducing rates of bone loss after two or more years of treatment. The pooled difference in percentage change from baseline was 2.05% (95% CI 0.24 to 3.86) for total body bone density, 1.66% (95% CI 0.92 to 2.39) for the lumbar spine at 2 years, 1.60% (95% CI 0.78 to 2.41) for the hip, and 1.91% (95% CI 0.33 to 3.50) for the distal radius. The relative risk of fractures of the vertebrae was 0.79 (95% CI 0.54 to 1.09); the relative risk for non-vertebral fractures was 0.86 (95% CI 0.43 to 1.72).

AUTHORS' CONCLUSIONS

Calcium supplementation alone has a small positive effect on bone density. The data show a trend toward reduction in vertebral fractures, but it is unclear if calcium reduces the incidence of non vertebral fractures.

A double-blind, randomized, placebo-controlled trial of itopride (100 and 200 mg three times daily) on gastric motor and sensory function in healthy volunteers

Itopride, a dopamine D2 antagonist and acetylcholinesterase inhibitor, significantly improved symptoms in patients with functional dyspepsia in one phase II randomized trial. However, the mechanisms by which itopride may improve symptoms are unknown. We aimed to compare the effects of two doses of itopride and placebo on gastric volumes, gastric emptying, small bowel transit and satiation in female and male healthy volunteers. Randomized, double-blind, placebo-controlled study evaluated gastric function before and after 7 days of itopride 100 mg (n = 16) or 200 mg (n = 15) or placebo (n = 15) t.i.d. Validated methods were used to study gastric accommodation (single photon emission computed tomography), gastric emptying and orocecal transit and satiation postnutrient challenge. The three arms were comparable with regard to age, gender and body mass index. There were no statistically significant effects of itopride on gastric emptying, orocecal transit, fasting gastric volume, maximum tolerated volume or aggregate symptom score with nutrient drink challenge. Postprandial (PP) change in gastric volume differed in the three groups (P = 0.019): 625[+/-28 (SEM)], 555(+/-26) and 512(+/-33) in placebo, itopride 100 and 200 mg groups, respectively. In healthy subjects, itopride reduced total PP gastric volume without accelerating gastric emptying or significantly altering gastric motor and sensory function in healthy individuals.

Double-blind, randomized, placebo-controlled study to evaluate the effects of tegaserod on gastric motor, sensory and myoelectric function in healthy volunteers

BACKGROUND

The effects of tegaserod on gastric accommodation and postprandial satiety remain unclear.

AIM

To compare the effects of tegaserod 6 mg twice daily vs. placebo on gastric volumes, postprandial symptoms, gastric emptying, small bowel transit and the surface electrogastrogram in female and male healthy volunteers.

METHODS

Randomized, double-blind, placebo-controlled study evaluated gastric function before and after 7 days of tegaserod 6 mg twice daily (n = 21) vs. placebo (n = 20) in healthy volunteers. Validated methods were used to study gastric emptying, myoelectrical activity, volumes and satiation postnutrient challenge.

RESULTS

There were no significant effects of tegaserod on the primary endpoints assessing gastric function: emptying of solids or liquids, total gastric volumes or myoelectrical activity. Maximum tolerated volume and aggregate symptom score with nutrient challenge on placebo were 1,035 mL (+/-44) and 130 (+/-15) vs. 989 mL (+/-43) and 117 (+/-15) during tegaserod, respectively (all P = N.S.). Postprandial change in proximal gastric volume by single photon emission-computed tomography was decreased in females on tegaserod (246 +/- 30) vs. placebo (358 +/- 32) (P = 0.015). Proximal fasting volumes in females were increased on tegaserod (126 +/- 12) vs. placebo (92 +/- 13) (P = 0.066).

CONCLUSIONS

While tegaserod decreased proximal gastric volume change after a meal, it does not appear to have significant effects on gastric motor and sensory function in healthy individuals. Further studies are required in patients with disturbances of gastric motor and sensory function.

Effect of H-7 and Lat-B on retinal physiology

PURPOSE

To investigate the effects of H-7 and Latrunculin B (Lat-B) on retinal vascular permeability and electrophysiology at concentrations that increase outflow facility in monkeys.

METHODS

One eye of 1 rhesus and 22 cynomolgus monkeys received an intravitreal bolus injection of H-7 or Lat-B; the opposite eye received vehicle. Multifocal electroretinograms (mfERGs), and photopic and scotopic full-field electroretinograms (ffERGs, sERGs) were recorded in subsets of monkeys at baseline and at multiple time-points post-H-7 or Lat-B. Vitreous fluorophotometry (VF) and fluorescein angiography (FA) were also performed.

RESULTS

No differences between the H-7 or Lat-B treated and control eyes were found in ffERGs, mfERGs, sERGs, or in FAs in any monkey. No significant difference was found in vitreous fluorescein levels between H-7 treated or Lat-B treated vs. control eyes.

CONCLUSIONS

No effect on retinal vascular permeability or retinal electrophysiology was apparent after intravitreal administration of H-7 or Lat-B at doses that increase outflow facility and lower IOP when given intracamerally.

Accuracy of the 7-8-9 Rule for endotracheal tube placement in the neonate

OBJECTIVE

To determine accuracy of the 7-8-9 Rule in a cohort of neonates.

STUDY DESIGN

This study was cross-sectional in design. Seventy-five consecutive neonates who required oral intubation from June 2004 to November 2004 for cardiopulmonary failure, respiratory distress, or surfactant administration were the subjects of this study. The initial endotracheal tube (ETT) depth of insertion was determined using either an estimated birth weight or actual weight in the 7-8-9 Rule calculation followed by auscultation and subsequent adjustment if necessary. Midtracheal position was identified as the point halfway between the inferior clavicle and carina on a chest radiograph. The initial depth was compared to the midtracheal depth to determine clinical accuracy of the 7-8-9 Rule. The depth predicted by the 7-8-9 Rule was also calculated using only actual weights. This predicted depth was compared to the midtracheal depth to determine true accuracy of the 7-8-9 Rule. Accuracy was determined using mean paired differences with 95% confidence intervals (CI) between initial or predicted depth and ideal, midtracheal ETT depth. Linear regression was used to adjust for confounding variables.

RESULTS

Mean (range) gestational age was 32 weeks (23 to 44 weeks) and weight was 2001 g (490 to 4400 g). Eighteen (24%) infants weighed 1000 g or less, 20 (27%) weighed between 1001 and 2000 g, 21 (28%) weighed between 2001 and 3000 g, 15 (20%) weighed between 3001 and 4000 g, and one (1%) weighed more than 4000 g. Thirteen of the 18 extremely low birth weight infants weighed <750 g. The initial depth of insertion was 0.004 cm above midtracheal position (95% CI -0.13 to 0.14, P = 0.96). After controlling for head position, the initial depth did not significantly differ from the midtracheal position among weight groups. Predicted depth using the 7-8-9 Rule placed the ETT 0.12 cm above midtracheal position (95% CI -0.30 to 0.06, P = 0.20). However, after controlling for head position, the 7-8-9 Rule positioned the ETT significantly below midtracheal position in infants weighing <750 g (mean 0.62 cm; 95% CI 0.30 to 0.93, P=0.002).

CONCLUSIONS

The 7-8-9 Rule appears to be an accurate clinical method for endotracheal tube placement in neonates weighing more than 750 g. When the 7-8-9 Rule is applied to infants weighing <750 g, caution is warranted. The current rule may lead to an overestimated depth of insertion and potentially result in clinically significant consequences.

152 SURVIVAL OF BIOPSIED DAY 15 BOVINE CONCEPTI RE-TRANSFERRED TO SYNCHRONIZED RECIPIENT HEIFERS

In cattle, a significant proportion of in vitro-produced (IVP) blastocysts do not result in viable pregnancies after transfer to recipient surrogates. Betteridge et al. (1980 J. Reprod. Fert. 59, 205–216) showed that it was possible after superovulation to recover elongated bovine embryos up to Day 17, transfer them into synchronized recipient cows, and have them develop further. We investigated the feasibility of recovering cattle embryos at Day 15, taking a sample of the trophoblast and transferring the embryos into recipients afterward for further development. The biopsied material could be used later to evaluate gene expression and correlate the profile retrospectively with developmental potential. With this approach, a larger amount of material is available for study and only embryos surviving to the elongation stage would be examined. In our experience, 30–40% of transferred blastocysts do not develop to the elongation stage. In three separate experiments, IVP embryos were generated using abattoir derived oocytes and cultured in SOF-aa supplemented with BSA (Thompson et al. 2000 J. Reprod. Fert. 118, 47–55). Six graded Day 7 (Day 0 = day of IVF) blastocysts were transferred into synchronized recipient heifers (n = 10 for each experiment). At Day 15 of gestation, concepti were flushed from the uteri after slaughter with EmCare Flush (ICPbio, Ltd., Suckland, New Zealand) containing 25 mg/mL kanamycin sulfate and then put into EmCare Hold. Conceptus lengths were measured and a proportion of those >30 mm long were cut off (5–15 mm) at one end and the trophoblast kept for future analysis. Pairs of cut or uncut (control) concepti were loaded into 0.25-mL embryo transfer straws. Each pair was transferred nonsurgically into recipients synchronized at Days 15 (Expt. 1, n = 17) or 13 (Expts. 2 and 3, n = 16 and 17, respectively) of the estrous cycle. The time between embryo flush and transfer to a recipient was noted. At Day 30, embryo survival was assessed at slaughter and compared using the Fisher's exact and chi-square. Day 15 conceptus lengths varied between 1 and 140 mm. The time between flush and transfer varied between 13 and 126 min and did not affect the ability of the concepti to subsequently establish pregnancies. Transfer to an earlier uterine environment did not significantly improve embryo survival. The proportion of embryos recovered at Day 30 was not affected by the biopsy. Up to 10 mm can be removed from 40–10 mm concepti without effect on subsequent survival. However, the overall survival post-Day 15 transfer is still too low for practical application. Table 1.

Do health care providers' attitudes towards back pain predict their treatment recommendations? Differential predictive validity of implicit and explicit attitude measures

The current study aimed to measure the differential predictive value of implicit and explicit attitude measures on treatment behaviour of health care providers. Thirty-six physiotherapy students completed a measure of explicit treatment attitude (Pain Attitudes And Beliefs Scale For Physiotherapists-PABS-PT) and a measure of implicit treatment attitude (Extrinsic Affective Simon Task-EAST). Furthermore, they gave treatment recommendations for a patient simulating back pain on three video scenes. The implicit and explicit measures of attitudes were only weakly related to each other. However, both were differentially related to treatment recommendations. The implications of the differential predictive value of implicit and explicit attitude measures for treatment behaviour are discussed.

226 GREATER DYSREGULATION OF GENE EXPRESSION IN PRE-IMPLANTATION CLONED OVINE COMPARED WITH CLONED BOVINE CONCEPTUSES

In our experience, the cloning of sheep by somatic cell nuclear transfer has been less successful than with cattle (5 v. 10% live births from embryo transfer). Here, we compare data collected over many years on the pre-implantation development of nuclear transfer (NT) ovine and bovine embryos with contemporary in vitro produced (IVP) embryos at the elongation (bovine Day 16–18 v. ovine Day 14) and allantois formation (bovine Day 26/27 v. ovine Day 21) stages. Sheep NT conceptuses were generated from three fibroblast types (skin, kidney, and lung) derived from a Day 100 female fetus. Bovine NT embryos were generated from a granulosa cell line derived from a mature dairy cow. The expression of a subset of genes (IGF2, H19, IGF2R, IGFBP-2, PEG1/Mest and trophoblast-expressed genes such as IFN-τ, TKDP-1, COX-2, and placental lactogen) was examined in both species at the two stages of development, using either Northern or slot-blot analysis. Pairwise comparisons between groups were carried out using Student's t-test. The proportion of ovine NT embryos that developed into blastocysts from the three cell types combined was 11% (117/1052) compared with 79% (86/109) for bovine NT from the one cell line. After transfer to synchronized recipients, 50–60% developed to the elongated conceptus stage for both species. Day 14 ovine NT (n = 19) and IVP (n = 26) conceptus lengths were similar whereas Day 16 bovine NT (n = 9) lengths were slightly shorter than those of IVP (n = 3) conceptuses (P > 0.05). However, only 30% (16/52) of ovine NT embryos developed to Day 21 compared with 64% (9/14) for Day 26/27 bovine NT. Bovine NT and IVP embryo and allantoic lengths were not significantly different; however, both lengths were shorter in ovine NT than in IVP controls (P < 0.05 and < 0.005, respectively). In each species, there was considerable individual variation in expression levels of most genes at each stage, probably due to variation in developmental stage of individuals even from the same day of gestation. The difference may be due to the timing of onset or termination of gene expression. In Day 16–18 bovine NT conceptuses, only the mean level of PEG1/Mest expression was significantly different (P < 0.05) from that of IVP conceptuses. In contrast, mean expression levels for TKDP-1 (P < 0.0001) and COX-2 (P < 0.05) were higher in ovine Day 14 NT, and PEG1/Mest was higher (P < 0.05) in Day 21 NT when compared with contemporary IVP controls. H19 and IGF2 expression was coordinately regulated in bovine NT and in ovine and bovine IVP conceptuses (IGF2 and H19 mRNA abundance was directly correlated). This coordinate regulation was disrupted in certain Day 21 ovine NT conceptuses, where high H19 levels occurred in the presence of low levels of IGF2, but not the converse. Thus, greater dysregulation in gene expression and loss of coordinate regulation of two key imprinted genes may explain the lower survival rate of ovine NT embryos to the early fetal stage when compared with bovine NT embryos. The effect of donor cell type on the species difference cannot be discounted. This work was supported by FRST C10X0303 programme.

Flavonoids, vitamin C and adenocarcinoma of the stomach

OBJECTIVE

To examine the role of six flavonoid classes (flavanones, flavan-3-ols, flavonols, flavones, anthocyanidins and isoflavones) and vitamin C in the aetiology of stomach cancer.

METHODS

Case-control study undertaken in Greece in the 1980s. Dietary information was obtained from 110 patients with incident stomach adenocarcinoma and 100 control patients. Flavonoid estimates were based on the recently released database of the US Department of Agriculture.

RESULTS

In models including sociodemographic variables, energy intake, vegetables, fruits and, alternatively, vitamin C the six flavonoid classes, only flavanones and vegetables remained significantly inversely associated with stomach cancer risk. The odds ratio (95% confidence intervals) per one standard deviation increase of intake of flavanones was 0.55 (0.31-0.96) whereas for vitamin C it was 1.05 (0.46-2.41). When fruits and vegetables were not adjusted for, both vitamin C and several flavonoid categories were inversely associated with stomach cancer risk, but these associations could be attributed to other compounds in these foods.

CONCLUSIONS

Among the major flavonoid classes studied, only flavanone intake is inversely associated with stomach cancer risk and could account for the apparent protective effect of fruit intake against this form of cancer. Additional factors, however, are likely to be involved in the consistent protection conveyed by vegetables.

Intake of specific flavonoid classes and coronary heart disease—a case–control study in Greece

OBJECTIVE

Dietary intake of flavonoids has been reported to protect against coronary heart disease (CHD) risk, but associations of specific classes of flavonoids with CHD have not been adequately studied.

DESIGN

Hospital-based case-control study relying on interviewer administered questionnaires.

SETTING

Cardiology Department of the University of Athens Medical School in the Hippokrateion General Hospital (1990-1991).

SUBJECTS

Cases were 329 patients with electrocardiographically confirmed first coronary infarct or a first positive coronary arteriogram, or both (participation fraction 93%). Controls were 570 patients admitted to the same hospital for minor conditions unrelated to nutrition (participation fraction 95%). All cases and controls were interviewed in the hospital wards by experienced interviewers, and a 110-item food frequency questionnaire was administered.

RESULTS

There was statistically significant evidence (P approximately 0.03) for an inverse association between intake of flavan-3-ols and CHD risk, an increase of about 21 mg per day corresponding to a 24% decrease in CHD risk. The inverse association between flavan-3-ols and CHD risk was largely accounted for by the intake of wine and to a lesser extent tea. For none of the other flavonoid classes was there statistically significant evidence of an association.

CONCLUSION

Flavan-3-ols, which are largely found in wine and tea, are inversely associated with, and may be protective against, coronary heart disease.

Potential applications of nicotinic ligands in the laboratory and clinic

The nicotinic acetylcholine receptor (nAChR) is a receptor, ion channel complex composed of five polypeptide subunits. There are many different nAChR subtypes constructed from a variety of different subunit combinations. This structural diversity contributes to the varied roles of nAChRs in the peripheral and central nervous system, and this diversity offers an excellent opportunity for chemists who are producing ligands. Subunit specific ligands could have wide and varied effects in the laboratory as experimental tools and in the clinic as therapeutic agents. Because presynaptic nAChRs have been shown to enhance the release of many neurotransmitters, new nicotinic ligands that potentiate nAChR activity would be very useful. Such ligands could enhance the release of various neurotransmitters during degenerative diseases that cause neurotransmitter systems to decrease their output. For example, boosting the release from cholinergic neurons would help patients with Alzheimer's disease, and boosting the release from dopaminergic neurons would help patients with Parkinson's disease.

52GREATER PHENOTYPIC VARIABILITY IN CLONED CATTLE FETUSES FROM ONE CELL LINE THAN CONTEMPORARY HALF-SIBS GENERATED BY ARTIFICIAL INSEMINATION OR IN VITRO EMBRYO PRODUCTION

The cloning of cattle by somatic cell nuclear transfer (NT) is associated with considerable variation in developmental abnormalities. Some of this variation may be due to the cell types/lines used and the specific production and culture methods for NT embryos. Fetal and placental development were studied in 24 pregnancies generated by NT (Wells et al., 2003 Theriogenology 59, 45–59) from a granulosa cell line. The controls consisted of 11 and 14 pregnancies resulting from in vitro-produced embryos (IVP) and artificial insemination (AI), respectively. All fetuses shared the same Friesian sire; oocytes for the derivation of NT or IVP embryos were obtained from abattoir-derived ovaries of Friesian cows. Morphometric measurements were made on the fetuses, fetal membranes, fluid volumes and placentomes at Days 50, 100 and 150 of gestation after slaughter. Pairwise comparisons of within group variances between the treatment groups were made using the F-test. The pregnancy loss from AI or embryo transfer to Day 150 was ∼40% for the AI and IVP groups. However, 60% of NT embryos transferred had been lost by Day 150. NT fetal weights at Day 100 were more variable than for the AI (P&lt;0.001) and IVP (P&lt;0.05) groups. The NT crown-rump lengths were also more variable compared with the IVP (P&lt;0.05) but not the AI group. At Day 100, NT heart (P&lt;0.01), kidney (P&lt;0.01) and liver (P&lt;0.05) weights were more variable compared with the AI group; both liver (P&lt;0.05) and kidney (P&lt;0.01) weights were similarly more variable in the Day 150 NT group. Part of this variability may be due to disproportionate organ growth in NT fetuses. Increased variability was most evident in the utero-placental tissues. At Day 50, the total fetal membrane weights were more variable in the NT compared with the AI (P&lt;0.001) but not the IVP group. The Day 50 IVP membrane weights were also more variable (P&lt;0.05) than for the AI group. The greater variability of the Day 150 NT membrane weights, when compared with AI (P&lt;0.05) or IVP (P&lt;0.01), could be due partly to greater variation in the allantoic and amniotic fluid volumes. Placentome numbers were significantly lower in the surviving Day 100 NT pregnancies but the weights of the total maternal caruncular tissue of the placentomes were significantly higher and more variable in the NT group (P&lt;0.05 for both AI and IVP). Placentome numbers in surviving NT pregnancies at Day 150 were similar to the controls. However, the total caruncle weights in both the NT and IVP groups were more variable when compared with the AI group (P&lt;0.05 for both). Thus, there is greater variability in fetal membrane and placental development in NT and, to a certain extent, IVP fetuses, when compared with the AI group. The increased variability within this NT group suggests that epigenetic effects arising from incomplete reprogramming of the donor genome and embryo culture can override genetic traits to a certain extent. Supported by FRST C10X0018.

Calcium supplementation on bone loss in postmenopausal women

BACKGROUND

Although calcium is one the simplest and least expensive strategies for preventing osteoporotic fractures calcium supplementation is nevertheless not without controversy (Kanis 1989; Nordin 1990). The Food and Drug Administration in the US has permitted a bone health claim for calcium-rich foods, and the NIH in its Consensus Development Process approved a statement that high calcium intake reduces the risk of osteoporosis.

OBJECTIVES

To assess the effects of calcium on bone density and fractures in postmenopausal women.

SEARCH STRATEGY

We searched Cochrane Controlled Register, MEDLINE and EMBASE up to 2001, and examined citations of relevant articles and proceedings of international meetings.

SELECTION CRITERIA

Trials that randomized postmenopausal women to calcium supplementation or usual calcium intake in the diet and reported bone mineral density of the total body, vertebral spine, hip, or forearm or recorded the number of fractures, and followed patients for at least one year were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Three independent reviewers assessed the methodologic quality and extracted data for each trial. For each bone density site (lumbar spine, total body, combined hip and combined forearm), we calculated the weighted mean difference in bone density between treatment and control groups using the percentage change from baseline. We constructed regression models in which the independent variables were year and dose, and the dependent variable was the effect size. This regression was used to determine the years across which pooling was appropriate. Heterogeneity was assessed. For each fracture analysis we calculated a risk ratio.

MAIN RESULTS

Fifteen trials, representing 1806 participants, were included. Calcium was more effective than placebo in reducing rates of bone loss after two or more years of treatment. The pooled difference in percentage change from baseline was 2.05% (95% CI 0.24 to 3.86) for total body bone density, 1.66% (95% CI 0.92 to 2.39) for the lumbar spine at 2 years, 1.60% (95% CI 0.78 to 2.41) for the hip, and 1.91% (95% CI 0.33 to 3.50) for the distal radius. The relative risk of fractures of the vertebrae was 0.79 (95% CI 0.54 to 1.09); the relative risk for non-vertebral fractures was 0.86 (95% CI 0.43 to 1.72).

REVIEWER'S CONCLUSIONS

Calcium supplementation alone has a small positive effect on bone density. The data show a trend toward reduction in vertebral fractures, but it is unclear if calcium reduces the incidence of non vertebral fractures.

Flavonoid intake and breast cancer risk: a case--control study in Greece

Flavonoids have been investigated for possible inverse associations with various chronic degenerative diseases, but there are no epidemiologic data concerning a possible association between several of the main flavonoid categories and breast cancer risk. We have applied recently published data on the flavonoid content of several foods and beverages on dietary information collected in the context of a large case–control study of 820 women with breast cancer and 1548 control women, conducted in Greece. We found a strong, statistically significant inverse association of flavone intake with breast cancer. The odds ratio for an increment equal to one standard deviation of daily flavone intake (i.e. 0.5 mg day⁻¹) was 0.87, with 95% confidence interval 0.77–0.97. The association persisted after controlling for fruit and vegetable consumption, or for other flavonoid intake. This inverse association is compatible with and may explain the reported inverse association of breast cancer with consumption of vegetables, particularly leafy vegetables. After controlling for dietary confounding, there was no association of breast cancer risk with flavanones, flavan-3-ols, flavonols, anthocyanidins or isoflavones.