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Non-tuberculous mycobacterium encephalitis is rare. Since 2013, a global outbreak of Mycobacterium chimaera infection has been attributed to point-source contamination of heater cooler units used in cardiac surgery. Disseminated M. chimaera infection has presented many unique challenges, including non-specific clinical presentations with delays in diagnosis, and a high mortality rate among predominantly immunocompetent adults. Here, we describe three patients with fatal disseminated Mycobacterium chimaera infection showing initially non-specific, progressively worsening neurocognitive decline, including confusion, delirium, depression and apathy. Autopsy revealed widespread granulomatous encephalitis of the cerebrum, brain stem and spinal cord, along with granulomatous chorioretinitis. Cerebral involvement and differentiation between mycobacterial granulomas and microangiopathic changes can be assessed best on MRI with contrast enhancement. The prognosis of M. chimaera encephalitis appears to be very poor, but might be improved by increased awareness of this new syndrome and timely antimicrobial treatment.
This presentation will enable the learner to:
1.Describe the clinical, radiological and neuropathological findings of Mycobacterium chimaera encephalitis
2.Be aware of this rare form of encephalitis, and explain its diagnosis, prognosis and management
We present a broad study of linear, clustered, noble gas puffs irradiated with the frequency doubled (527 nm) Titan laser at Lawrence Livermore National Laboratory. Pure Ar, Kr, and Xe clustered gas puffs, as well as two mixed-gas puffs consisting of KrAr and XeKrAr gases, make up the targets. Characterization experiments to determine gas-puff density show that varying the experimental parameter gas-delay timing (the delay between gas puff initialization and laser-gas-puff interaction) provides a simple control over the gas-puff density. X-ray emission (>1.4 keV) is studied as a function of gas composition, density, and delay timing. Xe gas puffs produce the strongest peak radiation in the several keV spectral region. The emitted radiation was found to be anisotropic, with smaller X-ray flux observed in the direction perpendicular to both laser beam propagation and polarization directions. The degree of anisotropy is independent of gas target type but increases with photon energy. X-ray spectroscopic measurements estimate plasma parameters and highlight their difference with previous studies. Electron beams with energy in excess of 72 keV are present in the noble gas-puff plasmas and results indicate that Ar plays a key role in their production. A drastic increase in harder X-ray emissions (X-ray flash effect) and multi-MeV electron-beam generation from Xe gas-puff plasma occurred when the laser beam was focused on the front edge of the linear gas puff.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Recently, the telecommunication market experiences an explosion in the subscribers of emergent high-debit services which require bandwidth that exceeds the one provided by actual copper based access networks . To cope with these demands and keep competitive, great efforts have been done to develop access networks based on optical technology, such as passive all-optical networks due to their intrinsic low cost . Sol-gel processing is suitable for the development of organic-inorganic hybrid (OIH) materials for the production of functional integrated optic (IO) devices in a cost effective way. Urea cross-linked OIH show acceptable transparency, mechanical flexibility and thermal stability [3-6]. The control over the refractive index is achieved by zirconium (IV) n-propoxide (ZPO) doping stabilized with methacrylic acid (MA) [3-5]. The combination in a single material of urea cross-linked OIH and ZPO allowed the preparation of UV written low losses planar waveguides  and low rugosity diffraction grating [4,5]. It has been demonstrated that MA acts not only as ZPO stabilizer but impacts directly on the photopolimerization properties as it contains a photopolymerizable group making the OIH easily UV patterned without photoinitiator . Moreover, it also impacts on the OHIs local structure as it forms a complex with ZPO, that originate ordered clusters dispersed within the OIH host [4,5]. Besides the potential of this OIH as IO components, the hybrid hosts are room-temperature efficient white light emitters lacking metal activator ions, presenting quantum yields as higher as 20 % . In this work, a series of OIH, so called di-ureasils, formed of a siliceous skeleton to which oligopolyether chains of different lengths are covalently grafted by means of urea bridges and modified by ZPO and MA will be prepared and characterized by X-ray and small angle X-ray diffractions, Raman, infrared, atomic force and photoluminescence spectroscopies. The use of the proposed OIH in the development of IO functionalities such as optical filters will be evaluated based on waveguide numerical simulation methods (beam propagation method). Waveguides will be written and characterized using the OIH aforementioned. The recording of a Bragg grating in the waveguides allow the implementation of a wavelength discrimination device with applications on optical filtering. The relevant properties of the devices, such as spectral rejection and insertion losses will be characterized.  S-J Park et al. Journal of Lightwave Tech. 22, 2004.  D.J. Shin et al., Journal of Lightwave Tech. 23, 2005.  C. Molina et al., J. Mater. Chem. 15, 3937, 2005.  R.A. Sá Ferreira et al., Proceedings of the International Conference on Telecomunications, 2006.  P.S. André et al. Proceedings ICTON, 1, We.C1.6, 223, 2006.  a) L.D. Carlos et al., Adv. Func. Mater. 11, 111, 2001; b) J. Chem. Phys. B. 108, 14924, 2004. Siemens SA and FCT (POCTI/CTM/59075/2004) is gratefully acknowledged.
Describe the epidemiological and molecular characteristics of an outbreak of Klebsiella pneumoniae carbapenemase (KPC)–producing organisms and the novel use of a cohorting unit for its control.
A 566-room academic teaching facility in Milwaukee, Wisconsin.
Solid-organ transplant recipients.
Infection control bundles were used throughout the time of observation. All KPC cases were intermittently housed in a cohorting unit with dedicated nurses and nursing aids. The rooms used in the cohorting unit had anterooms where clean supplies and linens were placed. Spread of KPC-producing organisms was determined using rectal surveillance cultures on admission and weekly thereafter among all consecutive patients admitted to the involved units. KPC-positive strains underwent pulsed-field gel electrophoresis and whole-genome sequencing.
A total of 8 KPC cases (5 identified by surveillance) were identified from April 2016 to April 2017. After the index patient, 3 patients acquired KPC-producing organisms despite implementation of an infection control bundle. This prompted the use of a cohorting unit, which immediately halted transmission, and the single remaining KPC case was transferred out of the cohorting unit. However, additional KPC cases were identified within 2 months. Once the cohorting unit was reopened, no additional KPC cases occurred. The KPC-positive species identified during this outbreak included Klebsiella pneumoniae, Enterobacter cloacae complex, and Escherichia coli. blaKPC was identified on at least 2 plasmid backbones.
A complex KPC outbreak involving both clonal and plasmid-mediated dissemination was controlled using weekly surveillances and a cohorting unit.
We assessed the impact of an embedded electronic medical record decision-support matrix (Cerner software system) for the reduction of hospital-onset Clostridioides difficile. A critical review of 3,124 patients highlighted excessive testing frequency in an academic medical center and demonstrated the impact of decision support following a testing fidelity algorithm.
Cardiac surgery-associated acute kidney injury is common. In order to improve our understanding of acute kidney injury, we formed the multi-centre Neonatal and Pediatric Heart and Renal Outcomes Network. Our main goals are to describe neonatal kidney injury epidemiology, evaluate variability in diagnosis and management, identify risk factors, investigate the impact of fluid overload, and explore associations with outcomes.
The Neonatal and Pediatric Heart and Renal Outcomes Network collaborative includes representatives from paediatric cardiac critical care, cardiology, nephrology, and cardiac surgery. The collaborative sites and infrastructure are part of the Pediatric Cardiac Critical Care Consortium. An acute kidney injury module was developed and merged into the existing infrastructure. A total of twenty-two participating centres provided data on 100–150 consecutive neonates who underwent cardiac surgery within the first 30 post-natal days. Additional acute kidney injury variables were abstracted by chart review and merged with the corresponding record in the quality improvement database. Exclusion criteria included >1 operation in the 7-day study period, pre-operative renal replacement therapy, pre-operative serum creatinine >1.5 mg/dl, and need for extracorporeal support in the operating room or within 24 hours after the index operation.
A total of 2240 neonatal patients were enrolled across 22 centres. The incidence of acute kidney injury was 54% (stage 1 = 31%, stage 2 = 13%, and stage 3 = 9%).
Neonatal and Pediatric Heart and Renal Outcomes Network represents the largest multi-centre study of neonatal kidney injury. This new network will enhance our understanding of kidney injury and its complications.
Transient (nuclear) heating experiments were conducted with uranium carbide fuel rods to study the failure characteristics of typical rod designs. Extremely unusual changes in microstructure were observed and the electron microprobe was employed to establish the disposition of materials resulting from the meltdown experiments. The probe results indicated substantial fuel-clad interactions and permitted the resolution of several uncertainties regarding the course of fuel rod failure and material redistribution. The electron microprobe represents a unique capability in the post-test analysis of such meltdown tests.
Improving quality of life (QOL) for people with dementia is a priority. In care homes, we often rely on proxy ratings from staff and family but we do not know if, or how, they differ in care homes.
We compared 1056 pairs of staff and family DEMQOL-Proxy ratings from 86 care homes across England. We explored factors associated with ratings quantitatively using multilevel modelling and, qualitatively, through thematic analysis of 12 staff and 12 relative interviews.
Staff and family ratings were weakly correlated (ρs = 0.35). Median staff scores were higher than family's (104 v. 101; p < 0.001). Family were more likely than staff to rate resident QOL as ‘Poor’ (χ2 = 55.91, p < 0.001). Staff and family rated QOL higher when residents had fewer neuropsychiatric symptoms and severe dementia. Staff rated QOL higher in homes with lower staff:resident ratios and when staff were native English speakers. Family rated QOL higher when the resident had spent longer living in the care home and was a native English. Spouses rated residents’ QOL higher than other relatives. Qualitative results suggest differences arise because staff felt good care provided high QOL but families compared the present to the past. Family judgements centre on loss and are complicated by decisions about care home placement and their understandings of dementia.
Proxy reports differ systematically between staff and family. Reports are influenced by the rater:staff and family may conceptualise QOL differently.
There are no estimates of the heritability of phenotypic udder traits in suckler sheep, which produce meat lambs, and whether these are associated with resilience to mastitis. Mastitis is a common disease which damages the mammary gland and reduces productivity. The aims of this study were to investigate the feasibility of collecting udder phenotypes, their heritability and their association with mastitis in suckler ewes. Udder and teat conformation, teat lesions, intramammary masses (IMM) and litter size were recorded from 10 Texel flocks in Great Britain between 2012 and 2014; 968 records were collected. Pedigree data were obtained from an online pedigree recording system. Univariate quantitative genetic parameters were estimated using animal and sire models. Linear mixed models were used to analyse continuous traits and generalised linear mixed models were used to analyse binary traits. Continuous traits had higher heritabilities than binary with teat placement and teat length heritability (h2) highest at 0.35 (SD 0.04) and 0.42 (SD 0.04), respectively. Udder width, drop and separation heritabilities were lower and varied with udder volume. The heritabilities of IMM and teat lesions (sire model) were 0.18 (SD 0.12) and 0.17 (SD 0.11), respectively. All heritabilities were sufficiently high to be in a selection programme to increase resilience to mastitis in the population of Texel sheep. Further studies are required to investigate genetic relationships between traits and to determine whether udder traits predict IMM, and the potential benefits from including traits in a selection programme to increase resilience to chronic mastitis.
Brandãoite, [BeAl2(PO4)2(OH)2(H2O)4](H2O), is a new Be–Al phosphate mineral from the João Firmino mine, Pomarolli farm region, Divino das Laranjeiras County, Minas Gerais State, Brazil, where it occurs in an albite pocket with other secondary phosphates, including beryllonite, atencioite and zanazziite, in a granitic pegmatite. It occurs as colourless acicular crystals <10 µm wide and <100 µm long that form compact radiating spherical aggregates up to 1.0–1.5 mm across. It is colourless and transparent in single crystals and white in aggregates, has a white streak and a vitreous lustre, is brittle and has conchoidal fracture. Mohs hardness is 6, and the calculated density is 2.353 g/cm3. Brandãoite is biaxial (+), α = 1.544, β = 1.552 and γ = 1.568, all ± 0.002; 2Vobs = 69.7(10)° and 2Vcalc = 71.2°. No pleochroism was observed. Brandãoite is triclinic, space group P
, a = 6.100(4), b = 8.616(4), c = 10.261(5) Å, α = 93.191(11), β = 95.120(11), γ = 96.863(11)°, V = 532.1(8) Å3 and Z = 2. Chemical analysis of a 4 µm wide needle-shaped crystal by electron microprobe and secondary-ion mass spectrometry gave P2O5 = 28.42, Al2O3 = 20.15, BeO = 4.85, H2O = 21.47 and sum = 74.89 wt.%. The empirical formula, normalised on the basis of 15 anions pfu with (OH) = 2 and (H2O) = 5 apfu (from the crystal structure) is Be0.98Al1.99P2.02H12O15. The crystal structure was solved by direct methods and refined to an R1 index of 7.0%. There are two P sites occupied by P5+, two Al sites occupied by octahedrally coordinated Al3+, and one Be site occupied by tetrahedrally coordinated Be2+. There are fifteen anions, two of which are (OH) groups and five of which are (H2O) groups. The simplified ideal formula is thus [BeAl2(PO4)2(OH)2(H2O)4](H2O) with Z = 2. Beryllium and P tetrahedra share corners to form a four-membered ring. Aluminium octahedra share a common vertex to form an [Al2φ11] dimer, and these dimers are cross-linked by P tetrahedra to form a complex slab of polyhedra parallel to (001). These slabs are cross-linked by BeO2(OH)(H2O) tetrahedra, with interstitial (H2O) groups in channels that extend along .
Norwood palliation for patients with single ventricle heart disease is associated with a significant risk for acute kidney injury, which portends a worse prognosis. We sought to investigate the impact of hybrid stage I palliation (Hybrid) on acute kidney injury risk.
This study is a single-centre prospective case–control study of seven consecutive neonates with single ventricle undergoing Hybrid palliation. Levels of serum creatinine and four novel urinary biomarkers, namely neutrophil gelatinase-associated lipocalin, interleukin-18, liver fatty acid-binding protein, and kidney injury molecule-1, were obtained before and after palliation. Acute kidney injury was defined as a ⩾50% increase in serum creatinine within 48 hours after the procedure. Data were compared with a contemporary cohort of 12 neonates with single ventricle who underwent Norwood palliation.
Patients who underwent Hybrid were more likely to be high-risk candidates (86 versus 25%, p=0.01) compared with those who underwent Norwood. Despite similar preoperative serum creatinine levels, there was a trend towards higher levels of postoperative peak serum creatinine (0.7 [0.63, 0.94] versus 0.56 [0.47, 0.74], p=0.06) and rate of acute kidney injury (67 versus 29%, p=0.17) in the Norwood cohort. Preoperative neutrophil gelatinase-associated lipocalin (58.4 [11, 86.3] versus 6.3 [5, 16.2], p=0.07) and interleukin-18 (30.6 [9.6, 167.2] versus 6.3 [6.3, 16.4], p=0.03) levels were higher in the Hybrid cohort. Nevertheless, longitudinal mixed-effect models demonstrated Hybrid palliation to be a protective factor against increased postoperative levels of neutrophil gelatinase-associated lipocalin (estimate −1.8 [−3.0, −9.0], p<0.001) and liver fatty acid-binding protein (−49.3 [−89.7, −8.8], p=0.018).
In this single-centre case–control study, postoperative acute kidney injury risk did not differ significantly by single ventricle stage I treatment strategy; however, postoperative elevation in novel urinary biomarkers, consistent with subclinical kidney injury, was encountered in the Norwood cohort but not in the Hybrid cohort.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
Knowledge regarding association of dietary branched-chain amino acid (BCAA) and type 2 diabetes (T2D), and the contribution of BCAA from meat to the risk of T2D are scarce. We evaluated associations between dietary BCAA intake, meat intake, interaction between BCAA and meat intake and risk of T2D. Data analyses were performed for 74 155 participants aged 50−79 years at baseline from the Women’s Health Initiative for up to 15 years of follow-up. We excluded from analysis participants with treated T2D, and factors potentially associated with T2D or missing covariate data. The BCAA and total meat intake was estimated from FFQ. Using Cox proportional hazards models, we assessed the relationship between BCAA intake, meat intake, and T2D, adjusting for confounders. A 20 % increment in total BCAA intake (g/d and %energy) was associated with a 7 % higher risk for T2D (hazard ratio (HR) 1·07; 95 % CI 1·05, 1·09). For total meat intake, a 20 % increment was associated with a 4 % higher risk of T2D (HR 1·04; 95 % CI 1·03, 1·05). The associations between BCAA intake and T2D were attenuated but remained significant after adjustment for total meat intake. These relations did not materially differ with or without adjustment for BMI. Our results suggest that dietary BCAA and meat intake are positively associated with T2D among postmenopausal women. The association of BCAA and diabetes risk was attenuated but remained positive after adjustment for meat intake suggesting that BCAA intake in part but not in full is contributing to the association of meat with T2D risk.
To describe the investigation and control of a rare cluster of Klebsiella pneumoniae carbapenemase–producing Citrobacter freundii in a hospital in southern Florida.
An epidemiologic investigation, review of infection prevention procedures, and molecular studies including whole genome sequencing were conducted.
An outbreak of K. pneumoniae carbapenemase–3-producing C. freundii was identified at a tertiary hospital in Florida in 2014. Of the 6 cases identified, 3 occurred in the same intensive care unit and were caused by the same clone. For 2 of the 3 remaining cases, the isolates had low carbapenem minimum inhibitory concentrations and were unrelated by whole genome sequencing. As a response to the outbreak, supplementary environmental cleaning was implemented, including closure and terminal cleaning of the unit where the 3 cases clustered, in addition to the infection control bundle already in place at the time. No further cases were identified after these additional interventions.
Although C. freundii is not a species that commonly demonstrates carbapenem resistance, our findings suggest that carbapenemase-producing C. freundii may be underdetected even when active surveillance is in place and has a potential to cause hospital outbreak.
This study aimed to determine whether age at introduction of solid foods was associated with feeding difficulties at 3 years of age. The present study was carried out using data from the Southampton Women’s Survey (SWS). Women enrolled in the SWS who subsequently became pregnant were followed-up during pregnancy and postpartum, and the offspring have been studied through childhood. Maternal socio-demographic and anthropometric data and child anthropometric and feeding data were collected through interviews and self-administered questionnaires. When the children were 3 years of age, mothers/carers rated six potential child feeding difficulty questions on a four-point Likert scale, including one general question and five specific feeding difficulty questions. Age at introduction of solids as a predictor of feeding difficulties was examined in 2389 mother–child pairs, adjusting for child (age last breast fed, sex, gestation) and maternal characteristics (parity, pre-pregnancy BMI, age, education, employment, parenting difficulties, diet quality). The majority of mothers/carers (61 %) reported some feeding difficulties (general feeding difficulty question) at 3 years of age, specifically with their child eating enough food (61 %), eating the right food (66 %) and being choosy with food (74 %). Children who were introduced to solids ≥6 months had a lower risk of feeding difficulties (RR 0·73; 95 % CI 0·59, 0·91, P=0·004) than children who were introduced to solids between 4 and 6 months. No other significant associations were found. There were few associations between feeding difficulties in relation to age at introduction of solid foods. However, general feeding difficulties were less common among infants introduced to solid foods ≥6 months of age.
Over the last decade, we have observed an escalating trend in the number of laryngeal biopsies performed, despite the incidence of laryngeal cancer remaining constant. This study aimed to quantify the rate of laryngeal biopsies and record the indications.
A retrospective analysis of laryngeal biopsies performed in North Glasgow, Scotland, UK, between 2001 and 2010, was conducted.
From 2001 to 2010, 3902 laryngeal biopsies were carried out in North Glasgow. Histopathological results indicated the following diagnoses: squamous cell carcinoma, in 889 cases (23 per cent); dysplasia, in 986 cases (25 per cent); ‘no tumour’, in 913 cases (23 per cent); and benign pathology, in the remaining 1084 cases (28 per cent). There has been a significant increase in the number of biopsies performed after 2004, with the incidence of squamous cell carcinoma and benign disease remaining relatively static.
It is hypothesised that organ preservation strategies, endoscopic resection in early stage laryngeal cancer and chemoradiotherapy in advanced head and neck cancer are responsible for the increase in laryngeal biopsies.
Congenital abnormalities of the coronary arteries in the absence of structural heart disease account for a small but interesting percentage of cardiac lesions in children. Their presentation may vary from incidental identification to aborted/sudden cardiac death. Patients with aborted sudden death episodes will require significant support if they develop extensive ischaemic myocardial injury. Ultimately, surgical repair should be carried out as soon as haemodynamic stability is attained and the neurological status is evaluated. The aims of this article were to provide a review of congenital abnormalities of the coronary arteries most commonly seen in children in the ICU as well as to review the current critical-care management thereof.
Anzaite-(Ce), ideally Ce43+Fe2+Ti6O18(OH)2, is a new, structurally complex mineral occurring as scarce minute crystals in hydrothermally altered silicocarbonatites in the Afrikanda alkali-ultramafic complex of the Kola Peninsula, Russia. The mineral is a late hydrothermal phase associated with titanite, hibschite, clinochlore and calcite replacing the primary magmatic paragenesis. The rare-earth elements (REE) (dominated by Ce), Ti and Fe incorporated in anzaite-(Ce) were derived from primary Ti oxides abundant in the host rock. Anzaite-(Ce) is brittle and lacks cleavage; the density calculated on the basis of structural data is 5.054(6) g cm–3. The mineral is opaque and grey with a bluish hue in reflected light; its reflectance values range from 15–16% at 440 nm to 13–14% at 700 nm. Its infrared spectrum shows a prominent absorption band at 3475 cm–1 indicative of OH– groups. The average chemical composition of anzaite-(Ce) gives the following empirical formula calculated on the basis of 18 oxygen atoms and two OH– groups: (Ce2.18Nd0.85La0.41Pr0.26Sm0.08Ca0.36Th0.01)Σ4.15Fe0.97(Ti5.68Nb0.22Si0.04)Σ5.94O18(OH)2. The mineral is monoclinic, space group C2/m, a = 5.290(2), b = 14.575(6), c = 5.234(2) Å, β = 97.233(7)°, V = 400.4(5) Å3, Z = 1. The ten strongest lines in the X-ray micro-diffraction pattern are [dobs in Å (I)hkl]: 2.596 (100) 002; 1.935 (18) 170; 1.506 (14) 133; 1.286 (13) 1.11.0; 2.046 (12) 241; 1.730 (12) 003; 1.272 (12) 0.10.2; 3.814 (11) 111; 2.206 (9) 061; 1.518 (9) 172. The structure of anzaite-(Ce), refined by single-crystal techniques to R1 = 2.1%, consists of alternating layers of type 1, populated by REE (+ minor Ca) in a square antiprismatic coordination and octahedrally coordinated Fe2+, and type 2, built of five-coordinate and octahedral Ti, stacked parallel to (001). This atomic arrangement is complicated by significant disorder affecting the Fe2+, five-coordinate Ti and two of the four anion sites. The order-disorder pattern is such that only one half of these positions in total occupy any given (010) plane, and the disordered (010) planes are separated by ordered domains comprising REE, octahedral Ti and two anion sites occupied by O2–. Structural and stoichiometric relations between anzaite-(Ce) and other REE-Ti (±Nb, Ta) oxides are discussed. The name anzaite-(Ce) is in honour of Anatoly N. Zaitsev of St Petersburg State University (Russia) and The Natural History Museum (UK), in recognition of his contribution to the study of carbonatites and REE minerals. The modifier reflects the prevalence of Ce over other REE in the composition of the new mineral.
Both maternal 25-hydroxyvitamin D (25(OH)D) concentrations during pregnancy and
placental amino acid transporter gene expression have been associated with
development of the offspring in terms of body composition and bone structure.
Several amino acid transporter genes have vitamin D response elements in their
promoters suggesting the possible linkage of these two mechanisms. We aimed to
establish whether maternal 25(OH)D and vitamin D-binding protein (VDBP) levels
relate to expression of placental amino acid transporters. RNA was extracted
from 102 placental samples collected in the Southampton Women's Survey,
and gene expression was analysed using quantitative real-time PCR. Gene
expression data were normalised to the geometric mean of three housekeeping
genes, and related to maternal factors and childhood body composition. Maternal
serum 25(OH)D and VDBP levels were measured by radioimmunoassay. Maternal
25(OH)D and VDBP levels were positively associated with placental expression of
specific genes involved in amino acid transport. Maternal 25(OH)D and VDBP
concentrations were correlated with the expression of specific placental amino
acid transporters, and thus may be involved in the regulation of amino acid
transfer to the fetus. The positive correlation of VDBP levels and placental
transporter expression suggests that delivery of vitamin D to the placenta may
be important. This exploratory study identifies placental amino acid
transporters which may be altered in response to modifiable maternal factors and
provides a basis for further studies.