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G Piaggio

Publications and source records attributed to G Piaggio.

At least 19 recordsLinked to original sources
PubMed2006

Cluster randomised trial of an active, multifaceted educational intervention based on the WHO Reproductive Health Library to improve obstetric practices.

OBJECTIVE: We conducted a trial to evaluate the effect of an active, multifaceted educational strategy to promote the use of the WHO Reproductive Health Library (RHL) on obstetric practices. DESIGN: Cluster randomised trial. The trial was assigned the International Standardised Randomised Controlled Trial Number ISRCTN14055385. SETTINGS: Twenty-two hospitals in Mexico City and 18 in the Northeast region of Thailand. METHODS: The intervention consisted primarily of three interactive workshops using RHL over a period of 6 months. The focus of the workshops was to provide access to knowledge and enable its use. A computer and support for using both the computer and RHL were provided at each hospital. The control hospitals did not receive any intervention. MAIN OUTCOME MEASURES: The main outcome measures were changes in ten selected clinical practices as recommended in RHL starting approximately four to six months after the third workshop. Clinical practice data were collected at each hospital from 1000 consecutively delivered women or for a 6-month period whichever was reached sooner. RESULTS: The active, multifaceted educational intervention we employed did not affect the ten targeted practices in a consistent and substantive way. Iron/folate supplementation, uterotonic use after birth and breastfeeding on demand were already frequently practiced, and we were unable to measure external cephalic version. Of the remaining six practices, selective, as opposed to routine episiotomy policy increased in the intervention group (difference in adjusted mean rate = 5.3%; 95% CI -0.1 to 10.7%) in Thailand, and there was a trend towards an increased use of antibiotics at caesarean section in Mexico (difference in adjusted mean rate = 19.0%; 95% CI: -8.0 to 46.0%). There were no differences in the use of labour companionship, magnesium sulphate use for eclampsia, corticosteroids for women delivering before 34 weeks and vacuum extraction. RHL awareness (24.8-65.5% in Mexico and 33.9-83.3% in Thailand) and use (4.8-34.9% in Mexico and 15.5-76.4% in Thailand) increased substantially after the intervention in both countries. CONCLUSION: The multifaceted, active strategy to provide health workers with the knowledge and skills to use RHL to improve their practice led to increased access to and use of RHL, however, no consistent or substantive changes in clinical practices were detected within 4-6 months after the third workshop.

Clinical Competence↗
PubMed2006

Progenitor cells trapped in marrow filters can reduce GvHD and transplant mortality.

A bone marrow harvest is filtered either in the operating room, in the laboratory or during infusion to the patient. Filters are usually discarded. Little is known of haemopoietic progenitor cells (HPCs) trapped in the filters. The aim of the study was to evaluate HPC content in the filters and to assess the outcome of transplants with filter-discarded or filter-recovered cells. Haemopoietic progenitors were grown from filters of 19 marrow transplants. We then compared the outcome of 39 filter-recovered transplants from HLA-identical siblings (years 2001-2004) with a matched cohort of 43 filter-discarded marrow grafts (years 1997-2000). Filters contained on average 21% long-term culture-initiating cells (LTC-IC) and 15% fibroblasts colony-forming units (CFU-F) of the total progenitor cell content. Filter-discarded transplants had significantly more grade II-IV graft-versus-host disease (GvHD) (42 vs 15%, P=0.008) as compared to filter-recovered transplants, and more transplant-related mortality (TRM) (20 vs 3%, P=0.04). The actuarial survival at 5 years is 69 vs 87%, respectively (P=0.15). This study suggests that a significant proportion of LTC-IC is lost in the filters together with CFU-F. Recovery and add back of progenitors trapped in the filters may reduce GvHD and TRM.

Adolescent↗
PubMed2004

Interventions for emergency contraception.

BACKGROUND: In emergency contraception a drug or IUD is used to prevent pregnancy shortly after unprotected intercourse. Except for some Western-European countries and China, emergency contraception is largely under-utilised worldwide. In many developing countries lack of access to emergency contraception may subject women to unsafe abortions, which contribute significantly to maternal mortality and morbidity. Currently, several interventions (IUD, the Yuzpe regimen, levonorgestrel, mifepristone, danazol and some combination regimens) are available for emergency contraception. Information on the comparative efficacy, safety and convenience of these methods is crucial for reproductive health care providers and the women they serve. OBJECTIVES: To determine which emergency contraceptive method following unprotected intercourse is the most effective, safe and convenient to prevent pregnancy. SEARCH STRATEGY: The search included the Cochrane Controlled Trials Register, Popline, MEDLINE, Chinese biomedical databases and UNDP/UNFPA/WHO/World Bank Special Programme on Human Reproduction (HRP) emergency contraception database (July 2003). Content experts and pharmaceutical companies were contacted. SELECTION CRITERIA: Randomised controlled trials and controlled clinical trials including women attending services for emergency contraception following a single act of unprotected intercourse were eligible. DATA COLLECTION AND ANALYSIS: Data on outcomes and trial characteristics were extracted in duplicate and independently by two reviewers. Quality assessment was also done by two reviewers independently. Meta-analysis results are expressed as relative risk (RR) using a fixed-effects model with 95% confidence interval (CI). In the presence of significant heterogeneity a random-effect model was applied. MAIN RESULTS: Forty-eight trials with 33110 women were included. Most trials were conducted in China (37/48). Levonorgestrel is more effective than the Yuzpe regimen in preventing pregnancy (2 trials, RR: 0.51; 95% CI: 0.31 to 0.83). Single dose (1.5 mg) administration seems to have similar effectiveness as the standard 12 hours apart split-dose (0.75 mg twice) of levonorgestrel (2 trials, RR: 0.77, 95% CI: 0.45 to 1.30). Levonorgestrel has similar effectiveness to mid-dose (8 trials, RR: 1.64; 95% CI: 0.82 to 3.25) or low-dose (7 trials, RR: 1.38; 95% CI: 0.93 to 2.05) mifepristone. Low-dose (=< 10 mg) mifepristone is similarly effective as mid doses (25-50 mg) when only high quality trials are considered. Delay in the onset of subsequent menses is the main unwanted effect of mifepristone and seems to be dose-related. The Yuzpe regimen can be used when levonorgestrel and mifepristone are not available. Half-dose Yuzpe with single administration is associated with fewer side-effects but it is not clear whether it is as effective as the standard Yuzpe regimen (RR: 1.41; 95% CI: 0.76 to 2.61). REVIEWERS' CONCLUSIONS: Levonorgestrel 1.5 mg (two split doses or a single dose) and low and mid-doses (25-50 mg) of mifepristone offer high efficacy with an acceptable side-effect profile. Single dose simplifies the use of levonorgestrel for emergency contraception without an increase in side-effects. However, mifepristone might delay the following menstruation, which could increase anxiety, particularly in higher doses. The Yuzpe regimen could be used if levonorgestrel or mifepristone are not available. The intrauterine device (IUD) is another effective emergency contraceptive, and can be kept for ongoing contraception.

Contraception, Postcoital↗
PubMed2003

Urinary diversion in infants with primary high-grade vesicoureteric reflux, urinary sepsis and renal function impairment.

INTRODUCTION: General consensus on the optimal treatment of septic infants with primary high-grade vesicoureteric reflux (VUR) and renal function impairment has not been reached. Our study aims at evaluating the role of temporary urinary diversion. MATERIALS AND METHODS: Twenty male infants, affected by sepsis and primary high-grade VUR, underwent urinary diversion in 1996-2001 because of estimated risk of renal function deterioration, due to non-compliance with the antibiotic treatment. Plasmatic creatinine clearance, ultrasonography, micturition cystography and scintigraphy were evaluated. RESULTS: Creatinine clearance was abnormal in 13 infants on admission, in 10 after urinary diversion and in 6 after second surgery. Renal damage (focal or diffuse) was evident in 16 patients, without modifications after surgery. No patient developed urinary tract infections (UTI). Vesicostomy was done in 12 cases, ureterostomy in 8. Nephrectomy was performed in 3 cases with poor renal function, and ureteroneocystostomy in 17. CONCLUSIONS: Urinary diversion in septic infants with high-grade VUR can represent an alternative approach to the conservative or surgical treatment in selected patients presenting risk of renal function impairment. This procedure allowed an easy management of UTI without worsening of renal function while waiting for a better anatomical status to perform reconstructive surgery.

Humans↗
PubMed2002

Mxi1 inhibits the proliferation of U87 glioma cells through down-regulation of cyclin B1 gene expression.

Mxi1 is a Mad family member that plays a role in cell proliferation and differentiation. To test the role of Mxi1 on tumorigenesis of glioma cells we transfected a CMV-driven MXI1 cDNA in U87 human glioblastoma cells. Two clones were isolated expressing MXI1 levels 18- and 3.5-fold higher than wild-type U87 cells (clone U87.Mxi1.14 and U87.Mxi1.22, respectively). In vivo, U87.Mxi1.14 cells were not tumorigenic in nude mice and delayed development of tumours was observed with U87.Mxi1.22 cells. In vitro, the proliferation rate was partially and strongly inhibited in U87.Mxi1.22 and U87.Mxi1.14 cells respectively. The cell cycle analysis revealed a relevant accumulation of U87.Mxi1.14 cells in the G(2)/M phase. Interestingly, the expression of cyclin B1 was inhibited to about 60% in U87.Mxi1.14 cells. This inhibition occurs at the transcriptional level and depends, at least in part, on the E-box present on the cyclin B1 promoter. Consistent with this, the endogenous Mxi1 binds this E-box in vitro. Thus, our findings indicate that Mxi1 can act as a tumour suppressor in human glioblastomas through a molecular mechanism involving the transcriptional down-regulation of cyclin B1 gene expression.

Basic Helix-Loop-Helix Proteins↗
PubMed2002

A randomized double-blind comparison of two single doses of mifepristone for emergency contraception.

BACKGROUND: Previous trials have shown the potential of 10 mg of mifepristone in emergency contraception. The aim of this trial was to investigate whether 10 mg of mifepristone has the same efficacy as 25 mg. METHODS: This double-blind, randomized trial was carried out in 10 family planning institutes and hospitals in China. Women who met recruitment criteria and requested emergency contraception within 120 h of a single act of unprotected coitus were randomized using a computer-generated list to either 10 or 25 mg of mifepristone within each centre. RESULTS: Among 3052 women enrolled, the outcome was known for 3030 women, 1516 in the 10 mg group and 1514 in the 25 mg group. Seventeen pregnancies occurred in each group, giving a pregnancy rate of 1.1%. The relative risk of pregnancy for women treated with 10 mg mifepristone compared with those treated with 25 mg was 1.0 (95% CI: 0.51-1.95) and equivalence was demonstrated within a two-fold margin. Both doses prevented 85-86% of pregnancies expected to have occurred if no treatment had been given. The pregnancy rate nearly doubled if women had further acts of intercourse. Efficacy decreased with treatment delay. Side-effects were uncommon and mild. CONCLUSIONS: A dose of 10 mg of mifepristone is sufficient for emergency contraception. Earlier treatment is preferable, although the method can be used effectively for up to 5 days after intercourse.

Adult↗
PubMed2002

The epidemiology of syphilis in pregnancy.

This study evaluated the magnitude, risk factors and outcomes of syphilis in pregnancy in a large cohort of women in four countries participating in the World Health Organization (WHO) antenatal care trial. All women attending the first prenatal care at each selected clinic were enrolled. Screening at the first antenatal visit was routinely performed with either rapid plasma reagin or Venereal Disease Research Laboratory and confirmed by fluorescent treponemal antibody absorption. All women also had the same syphilis tests after delivery. The initial prevalence, the incidence during pregnancy and the overall prevalence of syphilis at delivery were 0.9%, 0.4% and 1.3% respectively. Risk factors for syphilis during pregnancy were younger age for the incidence and older age and a history of stillbirth for the prevalence. Women with syphilis during pregnancy had significantly more adverse outcomes. We support the recommendation that in addition to the initial testing, a second routine test for syphilis ought to be established early in the third trimester even in low prevalence areas.

Adult↗
PubMed2002

Vesicoureteral reflux and ureteropelvic junction obstruction in children with horseshoe kidney: treatment and outcome.

PURPOSE: Horseshoe kidney is the most common renal fusion anomaly. We determined the treatment and outcome of vesicoureteral reflux and ureteropelvic junction obstruction in children with horseshoe kidney. MATERIALS AND METHODS: We reviewed the medical and radiological records of 52 consecutive children, including 32 boys and 20 girls, in whom horseshoe kidney was diagnosed at 2 children's hospitals during 1990 to 1999. Patient age at diagnosis was 1 day to 12 years (mean 3.9 years). In 2 children with horseshoe kidney neuropathic bladder was secondary to spina bifida and they were excluded from study. The diagnosis was made in all cases by abdominal ultrasound and confirmed by excretory urography or (99m)technetium-dimercaptosuccinic acid scan. Voiding cystourethrography was performed in 40 cases (80%). Patients were followed for 2 to 11 years (mean 4.2). RESULTS: Associated urological anomalies were identified in 26 patients (52%) with horseshoe kidney, including primary vesicoureteral reflux in 13, ureteropelvic junction obstruction in 12 and ectopic ureter in 1. Surgical intervention to correct the anomalies in 15 of the 26 children (58%) involved pyeloplasty in 8, ureteral reimplantation in 2, endoscopic treatment for vesicoureteral reflux in 2, ureterolithotomy in 1, upper pole heminephrectomy in 1 and valve fulguration in 1. No significant complications were observed in surgically treated patients. CONCLUSIONS: More than half of the patients with a clinically symptomatic horseshoe kidney have vesicoureteral reflux or ureteropelvic junction obstruction. Many patients with horseshoe kidney require surgical intervention for associated urological anomalies with good results.

Child↗
PubMed2001

Use of the equivalence approach in reproductive health clinical trials.

An equivalence trial is appropriate when it is desired to demonstrate equivalence between two treatments, regimens or interventions (methods) or non-inferiority of a new one compared to a standard one. The conduct of an equivalence trial requires different techniques during design and analysis compared to a superiority trial. The existing formulae for sample size calculation to demonstrate equivalence between two methods using the confidence interval approach are reviewed. The establishment of the margin of equivalence and the choice of the type of test are discussed. Plots of sample sizes required to demonstrate equivalence in the case of binary outcomes are presented for values of proportions and margins of equivalence common in the reproductive health field. Examples are given of method comparisons in the reproductive health field in which the relevant question is to demonstrate non-inferiority. The approach to equivalence is described in the trials included in three published systematic reviews in which these comparisons were conducted, addressing the statement of hypotheses, sample size calculation and the interpretation of results. The use of the conventional superiority approach to design equivalence trials has led to underpowered trials to show equivalence within clinical relevant margins. The analysis and interpretation of results from such trials has resulted in conclusions of equivalence based on lack of significance. We draw attention to the lack of awareness of the appropriate techniques for equivalence trials among researchers in the field of reproductive health. Finally, the issue of interim analyses and stopping rules in equivalence trials is addressed.

Confidence Intervals↗
PubMed2001

Diagnostic and clinical relevance of the number of circulating CD34(+) cells in myelofibrosis with myeloid metaplasia.

The absolute content of CD34(+) cells in the peripheral blood of 84 patients with myelofibrosis with myeloid metaplasia (MMM) and 23 patients with other Philadelphia-negative (Ph(-)) chronic myeloproliferative disorders (CMDs) was investigated. In MMM, the median absolute number of circulating CD34(+) cells was consistently high (91.6 x 10(6)/L; range, 0-2460 x 10(6)/L). Receiver operating characteristic curve analysis showed that 15 x 10(6)/L as a decision criterion for CD34(+) cells produced an almost complete discrimination between MMM patients out of therapy and other Ph(-) CMDs (positive predictive value, 98.4%; negative predictive value, 85.0%). MMM patients with higher numbers of CD34(+) cells had a significantly longer disease duration (P =.019) and higher spleen volume index (P =.014), liver volume (P =.000), percentage of circulating immature myeloid cells (P =.020), and percentage of myeloid blasts (P =.000). When CD34(+) cells were correlated with the use of Dupriez risk stratification, CD34(+) cells increased significantly from low-risk (median, 68.1 x 10(6)/L) to intermediate-risk (median, 112.8 x 10(6)/L) and high-risk patients (median 666.1 x 10(6)/L) (F = 4.95; P =.009). When CD34(+) cells were correlated with a severity score on the basis of both myeloproliferative and myelodepletive characteristics of the disease, only the myeloproliferation index was significantly associated with CD34(+) cell level (F = 5.7; P =.000). Overall survival and interval to blast transformation from the time of CD34(+) cell analysis were significantly shorter in patients with more than 300 x 10(6)/L CD34(+) cells (P =.005 and.0005, respectively). In conclusion, the absolute number of CD34(+) circulating cells allows MMM to be distinguished from other Ph(-) CMDs; it is strongly associated with the extent of myeloproliferation and predicts evolution toward blast transformation.

Adult↗
PubMed2001

The cyclin B1 gene is actively transcribed during mitosis in HeLa cells.

In mammalian cells, the expression level of the cyclin B1 gene plays a critical role in the progression through mitosis. Here we demonstrate that the transcriptional activity of the human cyclin B1 promoter, as well as the rate of gene transcription, is high during mitosis. Indeed, the cyclin B1 promoter maintains an open chromatin configuration at the mitotic stage. Consistent with this, we show that the cyclin B1 promoter is occupied and bound to NF-Y during mitosis in vivo. Our results provide the first example of RNA polymerase II-dependent transcription during mitosis in mammalian cells.

Blotting, Northern↗
PubMed2001

WHO multicentre randomised trial of misoprostol in the management of the third stage of labour.

BACKGROUND: Postpartum haemorrhage is a leading cause of maternal morbidity and mortality. Active management of the third stage of labour, including use of a uterotonic agent, has been shown to reduce blood loss. Misoprostol (a prostaglandin E1 analogue) has been suggested for this purpose because it has strong uterotonic effects, can be given orally, is inexpensive, and does not need refrigeration for storage. We did a multicentre, double-blind, randomised controlled trial to determine whether oral misoprostol is as effective as oxytocin during the third stage of labour. METHODS: In hospitals in Argentina, China, Egypt, Ireland, Nigeria, South Africa, Switzerland, Thailand, and Vietnam, we randomly assigned women about to deliver vaginally to receive 600 microg misoprostol orally or 10 IU oxytocin intravenously or intramuscularly, according to routine practice, plus corresponding identical placebos. The medications were administered immediately after delivery as part of the active management of the third stage of labour. The primary outcomes were measured postpartum blood loss of 1000 mL or more, and the use of additional uterotonics without an unacceptable level of side-effects. We chose an upper limit of a 35% increase in the risk of blood loss of 1000 mL or more as the margin of clinical equivalence, which was assessed by the confidence interval of the relative risk. Analysis was by intention to treat. FINDINGS: 9264 women were assigned misoprostol and 9266 oxytocin. 37 women in the misoprostol group and 34 in the oxytocin group had emergency caesarean sections and were excluded. 366 (4%) of women on misoprostol had a measured blood loss of 1000 mL or more, compared with 263 (3%) of those on oxytocin (relative risk 1.39 [95% CI 1.19-1.63], p<0.0001). 1398 (15%) women in the misoprostol group and 1002 (11%) in the oxytocin group required additional uterotonics (1.40 [1.29-1.51], p<0.0001). Misoprostol use was also associated with a significantly higher incidence of shivering (3.48 [3.15-3.84]) and raised body temperature (7.17 [5.67-9.07]) in the first hour after delivery. INTERPRETATION: 10 IU oxytocin (intravenous or intramuscular) is preferable to 600 microg oral misoprostol in the active management of the third stage of labour in hospital settings where active management is the norm.

Adult↗
PubMed2001

WHO antenatal care randomised trial for the evaluation of a new model of routine antenatal care.

BACKGROUND: We undertook a multicentre randomised controlled trial that compared the standard model of antenatal care with a new model that emphasises actions known to be effective in improving maternal or neonatal outcomes and has fewer clinic visits. METHODS: Clinics in Argentina, Cuba, Saudi Arabia, and Thailand were randomly allocated to provide either the new model (27 clinics) or the standard model currently in use (26 clinics). All women presenting for antenatal care at these clinics over an average of 18 months were enrolled. Women enrolled in clinics offering the new model were classified on the basis of history of obstetric and clinical conditions. Those who did not require further specific assessment or treatment were offered the basic component of the new model, and those deemed at higher risk received the usual care for their conditions; however, all were included in the new-model group for the analyses, which were by intention to treat. The primary outcomes were low birthweight (<2500 g), pre-eclampsia/eclampsia, severe postpartum anaemia (<90 g/L haemoglobin), and treated urinary-tract infection. There was an assessment of quality of care and an economic evaluation. FINDINGS: Women attending clinics assigned the new model (n=12568) had a median of five visits compared with eight within the standard model (n=11958). More women in the new model than in the standard model were referred to higher levels of care (13.4% vs 7.3%), but rates of hospital admission, diagnosis, and length of stay were similar. The groups had similar rates of low birthweight (new model 7.68% vs standard model 7.14%; stratified rate difference 0.96 [95% CI -0.01 to 1.92]), postpartum anaemia (7.59% vs 8.67%; 0.32), and urinary-tract infection (5.95% vs 7.41%; -0.42 [-1.65 to 0.80]). For pre-eclampsia/eclampsia the rate was slightly higher in the new model (1.69% vs 1.38%; 0.21 [-0.25 to 0.67]). Adjustment by several confounding variables did not modify this pattern. There were negligible differences between groups for several secondary outcomes. Women and providers in both groups were, in general, satisfied with the care received, although some women assigned the new model expressed concern about the timing of visits. There was no cost increase, and in some settings the new model decreased cost. INTERPRETATIONS: Provision of routine antenatal care by the new model seems not to affect maternal and perinatal outcomes. It could be implemented without major resistance from women and providers and may reduce cost.

Adult↗
PubMed2001

WHO systematic review of randomised controlled trials of routine antenatal care.

BACKGROUND: There is a lack of strong evidence on the effectiveness of the content, frequency, and timing of visits in standard antenatal-care programmes. We undertook a systematic review of randomised trials assessing the effectiveness of different models of antenatal care. The main hypothesis was that a model with a lower number of antenatal visits, with or without goal-oriented components, would be as effective as the standard antenatal-care model in terms of clinical outcomes, perceived satisfaction, and costs. METHODS: The interventions compared were the provision of a lower number of antenatal visits (new model) and a standard antenatal-visits programme. The selected outcomes were pre-eclampsia, urinary-tract infection, postpartum anaemia, maternal mortality, low birthweight, and perinatal mortality. We also selected measures of women's satisfaction with care and cost-effectiveness. This review drew on the search strategy developed for the Cochrane Pregnancy and Childbirth Group of the Cochrane Collaboration. FINDINGS: Seven eligible randomised controlled trials were identified. 57418 women participated in these studies: 30799 in the new-model groups (29870 with outcome data) and 26619 in the standard-model groups (25821 with outcome data). There was no clinically differential effect of the reduced number of antenatal visits when the results were pooled for pre-eclampsia (typical odds ratio 0.91 [95% CI 0.66-1.26]), urinary-tract infection (0.93 [0.79-1.10]). postpartum anaemia (1.01), maternal mortality (0.91 [0.55-1.51]), or low birthweight (1.04 [0.93-1.17]). The rates of perinatal mortality were similar, although the rarity of the outcome did not allow formal statistical equivalence to be attained. Some dissatisfaction with care, particularly among women in more developed countries, was observed with the new model. The cost of the new model was equal to or less than that of the standard model. INTERPRETATION: A model with a reduced number of antenatal visits, with or without goal-oriented components, could be introduced into clinical practice without risk to mother or baby, but some degree of dissatisfaction by the mother could be expected. Lower costs can be achieved.

Adult↗
PubMed2001

HSP-CBF is an NF-Y-dependent coactivator of the heat shock promoters CCAAT boxes.

The cellular response to toxic stimuli is elicited through the expression of heat shock proteins, a transcriptional process that relies upon conserved DNA elements in the promoters: the Heat Shock Elements, activated by the heat shock factors, and the CCAAT boxes. The identity of the CCAAT activator(s) is unclear because two distinct entities, NF-Y and HSP-CBF, have been implicated in the HSP70 system. The former is a conserved ubiquitous trimer containing histone-like subunits, the latter a 110-kDa protein with an acidic N-terminal. We analyzed two CCAAT-containing promoters, HSP70 and HSP40, with recombinant NF-Y and HSP-CBF using electrophoretic mobility shift assay, protein-protein interactions, transfections and chromatin immunoprecipitation assays (ChIP) assays. Both recognize a common DNA-binding protein in nuclear extracts, identified in vitro and in vivo as NF-Y. Both CCAAT boxes show high affinity for recombinant NF-Y but not for HSP-CBF. However, HSP-CBF does activate HSP70 and HSP40 transcription under basal and heat shocked conditions; for doing so, it requires an intact NF-Y trimer as judged by cotransfections with a diagnostic NF-YA dominant negative vector. HSP-CBF interacts in solution and on DNA with the NF-Y trimer through an evolutionary conserved region. In yeast two-hybrid assays HSP-CBF interacts with NF-YB. These data implicate HSP-CBF as a non-DNA binding coactivator of heat shock genes that act on a DNA-bound NF-Y.

Animals↗
PubMed2001

Methodological considerations on the design and analysis of an equivalence stratified cluster randomization trial.

The World Health Organization and collaborating institutions in four developing countries have conducted a multi-centre randomized controlled trial, in which clinics were allocated at random to two antenatal care (ANC) models. These were the standard 'Western' ANC model and a 'new' ANC model consisting of tests, clinical procedures and follow-up actions scientifically demonstrated to be effective in improving maternal and newborn outcomes. The two models were compared using the equivalence approach. This paper discusses the implications of the equivalence approach in the sample size calculation, analysis and interpretation of results of this cluster randomized trial. It reviews the ethical aspects regarding informed consent, concluding that the Zelen design has a place in cluster randomization trials. It describes the estimation of the intracluster correlation coefficient (ICC) in a stratified cluster randomized trial using two methods and reports estimates of the ICC obtained for many maternal, newborn and perinatal outcomes. Finally, it discusses analytical problems that arose: issues encountered using a composite index, heterogeneity of the intervention effect across sites, the choice of the method of analysis and the importance of efficacy analyses. The choice of the clustered Woolf estimator and the generalized estimating equations (GEE) as the methods of analysis applied is discussed.

Adult↗