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International gestational age-specific centiles for umbilical artery Doppler indices: a longitudinal prospective cohort study of the INTERGROWTH-21st Project.
BACKGROUND: Reference values for umbilical artery Doppler indices are used clinically to assess fetal well-being. However, many studies that have produced reference charts have important methodologic limitations, and these result in significant heterogeneity of reported reference ranges. OBJECTIVES: To produce international gestational age-specific centiles for umbilical artery Doppler indices based on longitudinal data and the same rigorous methodology used in the original Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project. STUDY DESIGN: In Phase II of the INTERGROWTH-21st Project (the INTERBIO-21st Study), we prospectively continued enrolling pregnant women according to the same protocol from 3 of the original populations in Pelotas (Brazil), Nairobi (Kenya), and Oxford (United Kingdom) that had participated in the Fetal Growth Longitudinal Study. Women with a singleton pregnancy were recruited at <14 weeks' gestation, confirmed by ultrasound measurement of crown-rump length, and then underwent standardized ultrasound every 5±1 weeks until delivery. From 22 weeks of gestation umbilical artery indices (pulsatility index, resistance index, and systolic/diastolic ratio) were measured in a blinded fashion, using identical equipment and a rigorously standardized protocol. Newborn size at birth was assessed using the international INTERGROWTH-21st Standards, and infants had detailed assessment of growth, nutrition, morbidity, and motor development at 1 and 2 years of age. The appropriateness of pooling data from the 3 study sites was assessed using variance component analysis and standardized site differences. Umbilical artery indices were modeled as functions of the gestational age using an exponential, normal distribution with second-degree fractional polynomial smoothing; goodness of fit for the overall models was assessed. RESULTS: Of the women enrolled at the 3 sites, 1629 were eligible for this study; 431 (27%) met the entry criteria for the construction of normative centiles, similar to the proportion seen in the original fetal growth longitudinal study. They contributed a total of 1243 Doppler measures to the analysis; 74% had 3 measures or more. The healthy low-risk status of the population was confirmed by the low rates of preterm birth (4.9%) and preeclampsia (0.7%). There were no neonatal deaths and satisfactory growth, health, and motor development of the infants at 1 and 2 years of age were documented. Only a very small proportion (2.8%-6.5%) of the variance of Doppler indices was due to between-site differences; in addition, standardized site difference estimates were marginally outside this threshold in only 1 of 27 comparisons, and this supported the decision to pool data from the 3 study sites. All 3 Doppler indices decreased with advancing gestational age. The 3rd, 5th 10th, 50th, 90th, 95th, and 97th centiles according to gestational age for each of the 3 indices are provided, as well as equations to allow calculation of any value as a centile and z scores. The mean pulsatility index according to gestational age = 1.02944 + 77.7456*(gestational age)-2 - 0.000004455*gestational age3. CONCLUSION: We present here international gestational age-specific normative centiles for umbilical artery Doppler indices produced by studying healthy, low-risk pregnant women living in environments with minimal constraints on fetal growth. The centiles complement the existing INTERGROWTH-21st Standards for assessment of fetal well-being
What is the balance of benefits and harms for lung cancer screening with low-dose computed tomography?
After the National Lung Screening Trial (NLST)1 demonstrated improved lung cancer mortality almost a decade ago, hopes have been raised that low-dose computed tomography could be used to detect lung cancer in asymptomatic populations and improve outcomes by reducing the number of people diagnosed with advanced disease. The publication of the long-awaited Nederlands-Leuvens Longkanker Screenings Onderzoek (NELSON) trial last year2 has provided further evidence of a lung cancer mortality benefit and has provoked further calls to implement national population-based screening programmes, but the case for lung cancer screening remains controversial
Early-stage lung cancer associated with higher frequency of chest x-ray up to three years prior to diagnosis
Objectives:
Symptom awareness campaigns have contributed to improved early detection of lung cancer. Previous research suggests that this may have been achieved partly by diagnosing lung cancer in those who were not experiencing symptoms of their cancer. This study aimed to explore the relationship between frequency of chest x-ray in the three years prior to diagnosis and stage at diagnosis.
Settings:
Lung cancer service in a UK teaching hospital.
Participants:
Patients diagnosed with lung cancer between 2010 and 2013 were identified. The number of chest x-rays for each patient in the three years prior to diagnosis was recorded. Statistical analysis of chest x-ray frequency comparing patients with early- and late-stage disease was performed.
Results:
One-thousand seven-hundred fifty patients were included â 589 (33.7%) with stage I/II and 1,161 (66.3%) with stage III/IV disease. All patients had at least one chest x-ray in the six months prior to diagnosis. Those with early-stage disease had more chest x-rays in this period (1.32 vs 1.15 radiographs per patient, P = 0.009). In the period 36 months to six months prior to lung cancer diagnosis, this disparity was even greater (1.70 vs 0.92, radiographs per patient, P < 0.001).
Conclusions:
Increased rates of chest x-ray are likely to contribute to earlier detection. Given the known symptom lead time many patients diagnosed through chest x-ray may not have been experiencing symptoms caused by their cancer. The number of chest x-rays performed could reflect patient and/or clinician behaviours in response to symptoms
International standards for fetal brain structures based on serial ultrasound measurements from the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project.
OBJECTIVE: To create prescriptive growth standards for five fetal brain structures, measured by ultrasound, from healthy, well-nourished women, at low risk of impaired fetal growth and poor perinatal outcomes, taking part in the Fetal Growth Longitudinal Study (FGLS) of the INTERGROWTH-21st Project. METHODS: This was a complementary analysis of a large, population-based, multicentre, longitudinal study. We measured, in planes reconstructed from 3-dimensional (3D) ultrasound volumes of the fetal head at different time points in pregnancy, the size of the parieto-occipital fissure (POF), Sylvian fissure (SF), anterior horn of the lateral ventricle (AV), atrium of the posterior ventricle (PV) and cisterna magna (CM). The sample analysed was randomly selected from the overall FGLS population, ensuring an equal distribution amongst the eight diverse participating sites and of 3D ultrasound volumes across pregnancy (range: 15 - 36âweeks' gestation). Fractional polynomials were used to the construct standards. Growth and development of the infants were assessed at 1 and 2âyears of age to confirm their adequacy for constructing international standards. RESULTS: From the entire FGLS cohort of 4321 women, 451 (10.4%) were randomly selected. After exclusions, 3D ultrasound volumes from 442 fetuses born without congenital malformations were used to create the charts. The fetal brain structures of interest were identified in 90% of cases. All structures showed increasing size with gestation and increasing variability for the POF, SF, PV and CM. The 3rd , 5th , 50th , 95th and 97th smoothed centile are presented. The 5th centile of POF and SF were 2.8 and 4.3 at 22âweeks and 4.2 and 9.4mm at 32âweeks respectively. The 95th centile of PV and CM were 8.5 and 7.4 at 22âweeks and 8.5 and 9.4mm at 32âweeks respectively. CONCLUSIONS: We have produced prescriptive size standards for fetal brain structures based on prospectively enrolled pregnancies at low risk of abnormal outcomes. We recommend these as international standards for the assessment of measurements obtained by ultrasound from fetal brain structures
Assessing the Health of Richibucto Estuary with the Latent Health Factor Index
The ability to quantitatively assess the health of an ecosystem is often of
great interest to those tasked with monitoring and conserving ecosystems. For
decades, research in this area has relied upon multimetric indices of various
forms. Although indices may be numbers, many are constructed based on
procedures that are highly qualitative in nature, thus limiting the
quantitative rigour of the practical interpretations made from these indices.
The statistical modelling approach to construct the latent health factor index
(LHFI) was recently developed to express ecological data, collected to
construct conventional multimetric health indices, in a rigorous quantitative
model that integrates qualitative features of ecosystem health and preconceived
ecological relationships among such features. This hierarchical modelling
approach allows (a) statistical inference of health for observed sites and (b)
prediction of health for unobserved sites, all accompanied by formal
uncertainty statements. Thus far, the LHFI approach has been demonstrated and
validated on freshwater ecosystems. The goal of this paper is to adapt this
approach to modelling estuarine ecosystem health, particularly that of the
previously unassessed system in Richibucto in New Brunswick, Canada. Field data
correspond to biotic health metrics that constitute the AZTI marine biotic
index (AMBI) and abiotic predictors preconceived to influence biota. We also
briefly discuss related LHFI research involving additional metrics that form
the infaunal trophic index (ITI). Our paper is the first to construct a
scientifically sensible model to rigorously identify the collective explanatory
capacity of salinity, distance downstream, channel depth, and silt-clay content
--- all regarded a priori as qualitatively important abiotic drivers ---
towards site health in the Richibucto ecosystem.Comment: On 2013-05-01, a revised version of this article was accepted for
publication in PLoS One. See Journal reference and DOI belo
The Impact of NOD2 Variants on Fecal Microbiota in Crohn's Disease and Controls Without Gastrointestinal Disease.
BACKGROUND/AIMS: Current models of Crohn's disease (CD) describe an inappropriate immune response to gut microbiota in genetically susceptible individuals. NOD2 variants are strongly associated with development of CD, and NOD2 is part of the innate immune response to bacteria. This study aimed to identify differences in fecal microbiota in CD patients and non-IBD controls stratified by NOD2 genotype. METHODS: Patients with CD and non-IBD controls of known NOD2 genotype were identified from patients in previous UK IBD genetics studies and the Cambridge bioresource (genotyped/phenotyped volunteers). Individuals with known CD-associated NOD2 mutations were matched to those with wild-type genotype. We obtained fecal samples from patients in clinical remission with low fecal calprotectin (<250 ”g/g) and controls without gastrointestinal disease. After extracting DNA, the V1-2 region of 16S rRNA genes were polymerase chain reaction (PCR)-amplified and sequenced. Analysis was undertaken using the mothur package. Volatile organic compounds (VOC) were also measured. RESULTS: Ninety-one individuals were in the primary analysis (37 CD, 30 bioresource controls, and 24 household controls). Comparing CD with nonIBD controls, there were reductions in bacterial diversity, Ruminococcaceae, Rikenellaceae, and Christensenellaceae and an increase in Enterobacteriaceae. No significant differences could be identified in microbiota by NOD2 genotype, but fecal butanoic acid was higher in Crohn's patients carrying NOD2 mutations. CONCLUSIONS: In this well-controlled study of NOD2 genotype and fecal microbiota, we identified no significant genotype-microbiota associations. This suggests that the changes associated with NOD2 genotype might only be seen at the mucosal level, or that environmental factors and prior inflammation are the predominant determinant of the observed dysbiosis in gut microbiota.Funding was supported by CORE, the Digestive Diseases Foundation and the Wellcome Trust [grant number 097943 to NAK, 093885 to CAL and 098051 to Alan W Walker and Julian Parkhill . Dr. Walker receives core funding support from the Scottish Government Rural and Environmental Science and Analysis Service (RESAS). We also acknowledge the NIHR Biomedical Research Centre awards to Addenbrookeâs Hospital/University of Cambridge School of Clinical Medicine and acknowledge the NIHR Newcastle Biomedical Research Centre
Pathological Investigation of Congenital Bicuspid Aortic Valve Stenosis, Compared with Atherosclerotic Tricuspid Aortic Valve Stenosis and Congenital Bicuspid Aortic Valve Regurgitation
Congenital bicuspid aortic valve (CBAV) is the main cause of aortic stenosis (AS) in young adults. However, the histopathological features of AS in patients with CBAV have not been fully investigated.We examined specimens of aortic valve leaflets obtained from patients who had undergone aortic valve re/placement at our institution for severe AS with CBAV (n = 24, CBAV-AS group), severe AS with tricuspid aortic valve (n = 24, TAV-AS group), and severe aortic regurgitation (AR) with CBAV (n = 24, CBAV-AR group). We compared the histopathological features among the three groups. Pathological features were classified using semi-quantitative methods (graded on a scale 0 to 3) by experienced pathologists without knowledge of the patients' backgrounds. The severity of inflammation, neovascularization, and calcium and cholesterol deposition did not differ between the CBAV-AS and TAV-AS groups, and these four parameters were less marked in the CBAV-AR group than in the CBAV-AS (all p<0.01). Meanwhile, the grade of valvular fibrosis was greater in the CBAV-AS group, compared with the TAV-AS and CBAV-AR groups (both p<0.01). In AS patients, thickness of fibrotic lesions was greater on the aortic side than on the ventricular side (both p<0.01). Meanwhile, thickness of fibrotic lesions was comparable between the aortic and ventricular sides in CBAV-AR patients (p = 0.35).Valvular fibrosis, especially on the aortic side, was greater in patients with CBAV-AS than in those without, suggesting a difference in the pathogenesis of AS between CBAV and TAV
Poly(ADP-ribose) polymerase family member 14 (PARP14) is a novel effector of the JNK2-dependent pro-survival signal in multiple myeloma
Copyright @ 2013 Macmillan Publishers Limited. This is the author's accepted manuscript. The final published article is available from the link below.Regulation of cell survival is a key part of the pathogenesis of multiple myeloma (MM). Jun N-terminal kinase (JNK) signaling has been implicated in MM pathogenesis, but its function is unclear. To elucidate the role of JNK in MM, we evaluated the specific functions of the two major JNK proteins, JNK1 and JNK2. We show here that JNK2 is constitutively activated in a panel of MM cell lines and primary tumors. Using loss-of-function studies, we demonstrate that JNK2 is required for the survival of myeloma cells and constitutively suppresses JNK1-mediated apoptosis by affecting expression of poly(ADP-ribose) polymerase (PARP)14, a key regulator of B-cell survival. Strikingly, we found that PARP14 is highly expressed in myeloma plasma cells and associated with disease progression and poor survival. Overexpression of PARP14 completely rescued myeloma cells from apoptosis induced by JNK2 knockdown, indicating that PARP14 is critically involved in JNK2-dependent survival. Mechanistically, PARP14 was found to promote the survival of myeloma cells by binding and inhibiting JNK1. Moreover, inhibition of PARP14 enhances the sensitization of MM cells to anti-myeloma agents. Our findings reveal a novel regulatory pathway in myeloma cells through which JNK2 signals cell survival via PARP14, and identify PARP14 as a potential therapeutic target in myeloma.Kay Kendall Leukemia Fund, NIH, Cancer Research UK, Italian Association for Cancer Research and the Foundation for Liver Research
Mirroring everyday clinical practice in clinical trial design: a new concept to improve the external validity of randomized double-blind placebo-controlled trials in the pharmacological treatment of major depression
Background: Randomized, double-blind, placebo-controlled trials constitute the gold standard in clinical research when testing the efficacy of new psychopharmacological interventions in the treatment of major depression. However, the blinded use of placebo has been found to influence clinical trial outcomes and may bias patient
selection.
Discussion: To improve clinical trial design in major depression so as to reflect clinical practice more closely we propose to present patients with a balanced view of the benefits of study participation irrespective of their assignment to placebo or active treatment. In addition every participant should be given the option to finally
receive the active medication. A research agenda is outlined to evaluate the impact of the proposed changes on the efficacy of the drug to be evaluated and on the demographic and clinical characteristics of the enrollment fraction with regard to its representativeness of the eligible population.
Summary: We propose a list of measures to be taken to improve the external validity of double-blind, placebocontrolled trials in major depression. The recommended changes to clinical trial design may also be relevant for other psychiatric as well as medical disorders in which expectations regarding treatment outcome may affect the
outcome itself
A systematic review to determine use of the Endometriosis Health Profiles to measure quality of life outcomes in women with endometriosis
BACKGROUND The Endometriosis Health Profiles (EHPs), the EHP-30 and EHP-5, are patient-reported outcome measures that were developed to measure the health-related quality of life (HRQoL) of women living with endometriosis. Prior to their development, a systematic review was undertaken which identified that the HRQoL of women living with endometriosis was poorly understood, with only three medical and one surgical study identified. OBJECTIVE AND RATIONALE The 20-year anniversary of the EHP-30 provided a timely opportunity to assess how the tools have been used and explore what the findings tell us about the impact of endometriosis and its associated treatments upon womenâs QoL. Applying robust systematic review methodology, following PRISMA guidelines, we sought to answer: How many studies have used the EHP and for what purpose?; What are the demographic characteristics and international context of the studies?; What is the methodological nature and quality of the studies?; Which interventions have been assessed and what are the reported EHP outcomes?; and Can the EHP outcomes of these interventions be analysed using a meta-analysis and, if so, what do the results show? SEARCH METHODS The electronic databases MEDLINE, CINAHL, PsycINFO, PubMed, and Google Scholar were searched from the year the EHP was first published, in 2001 to 26 February 2020 using the search terms âEHP30â, âEHP5â, âEHP-30â, âEHP-5â, âendometriosis health profile 30â, and âendometriosis health profile 5â. We updated the searches on 9 April 2021. All included studies were quality assessed using the Mixed Methods Appraisal Tool (MMAT). OUTCOMES The review included 139 papers. In clinical intervention studies, the EHPs were deployed most frequently to measure the outcomes of medical (nâ=â35) and surgical (nâ=â21) treatment. The EHPs were also used in 13 other intervention studies, 29 non-interventional studies, 32 psychometric/cross cultural validation studies; six diagnostic studies, and in three other studies to measure outcomes in related conditions. They were mainly deployed in studies undertaken in Europe and North America. Overall, regardless of the nature of the intervention, most women reported improvements in HRQoL after treatment. Surgical interventions generally resulted in significant improvements for the longest amount of time. There was also evidence that when participants stopped taking medication their EHP scores worsened, perhaps reinforcing the temporary impact of medical treatment. Younger patients reported more negative impact upon their HRQoL. Further evidence using classical test theory to support the EHPsâ robust psychometric properties, including acceptability, dimensionality, reliability, validity (including cross-cultural), and responsiveness, was demonstrated, particularly for the EHP-30. Strikingly, using anchor-based methods, EHP-30 responsiveness studies demonstrate the largest mean changes in the âcontrol and powerlessnessâ domain post-intervention, followed by âpainâ. MMAT outcomes indicated the quality of the papers was good, with the exception of five studies. A meta-analysis was not undertaken owing to the heterogeneity of the interventions and papers included in this review. WIDER IMPLICATIONS Women with endometriosis face a lifetime of surgical and/or medical interventions to keep the condition under control. Less invasive treatments that can lead to improved longer term physical and psycho-social outcomes are needed. The EHPs are reliable, valid, acceptable, and responsive tools, but more assessment of EHP outcomes using modern psychometric methods and in the context of women from ethnically diverse backgrounds and in routine clinical care would be beneficial. Given the brevity of the EHP-5, it may be the most appropriate version to use in routine clinical practice, whereas the longer EHP-30, which provides more granularity, is more appropriate for research
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