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In August 2019, public health surveillance systems in Scotland and England identified seven, geographically dispersed cases infected with the same strain (defined as isolates that fell within the same five single nucleotide polymorphism single linage cluster) of Shiga toxin-producing Escherichia coli O157:H7. Epidemiological analysis of enhanced surveillance questionnaire data identified handling raw beef and shopping from the same national retailer (retailer A) as the common exposure. Concurrently, a microbiological survey of minced beef at retail identified the same strain in a sample of minced beef sold by retailer A, providing microbiological evidence of the link. Between September and November 2019, a further four primary and two secondary cases infected with the same strain were identified; two cases developed haemolytic uraemic syndrome. None of the four primary cases reported consumption of beef from retailer A and the transmission route of these subsequent cases was not identified, although all four primary cases visited the same petting farm. Generally, outbreaks of STEC O157:H7 in the UK appear to be distinct, short-lived events; however, on-going transmission linked to contaminated food, animals or environmental exposures and person-to-person contact do occur. Although outbreaks of STEC caused by contaminated fresh produce are increasingly common, undercooked meat products remain a risk of infection.
An examination of invasive procedure cancellations found that the lack of pre-procedural oral screening was a preventable cause, for children with congenital heart disease. The purpose of this study was to implement an oral screening tool within the paediatric cardiology clinic, with referral to paediatric dental providers for positive screens. The target population were children aged ≥6 months to <18 years old, being referred for cardiac procedures.
The quality implementation framework method was used for this study design. The multi-modal intervention included education, audit and feedback, screening guidelines, environmental support, and interdisciplinary collaboration. Baseline rates for oral screenings were determined by retrospective chart audit from January 2018 to January 2019 (n = 211). Provider adherence to the oral screening tool was the outcome measure. Positive oral screens, resulting in referral to the paediatric dental clinic, were measured as a secondary outcome. Provider adherence rates were used as a process measure.
Data collected over 14 weeks showed a 29% increase in documentation of oral screenings prior to referral, as compared to the retrospective chart audit. During the study period, 13% of completed screenings were positive (n = 5). Provider compliance for the period was averaged at 70% adherence.
A substantial increase in pre-procedural oral screenings by paediatric cardiologists was achieved using the quality implementation framework and targeted interventions.
Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
The Last Glacial–Interglacial Transition (LGIT; 15,000–11,000 cal BP) was characterized by complex spatiotemporal patterns of climate change, with numerous studies requiring accurate chronological control to decipher leads from lags in global paleoclimatic, paleoenvironmental, and archaeological records. However, close scrutiny of the few available tree-ring chronologies and radiocarbon-dated sequences composing the IntCal13 14C calibration curve indicates significant weakness in 14C calibration across key periods of the LGIT. Here, we present a decadally resolved atmospheric 14C record derived from New Zealand kauri spanning the Lateglacial from ~13,100–11,365 cal BP. Two floating kauri 14C time series, curve-matched to IntCal13, serve as a 14C backbone through the Younger Dryas. The floating Northern Hemisphere (NH) 14C data sets derived from the YD-B and Central European Lateglacial Master tree-ring series are matched against the new kauri data, forming a robust NH 14C time series to ~14,200 cal BP. Our results show that IntCal13 is questionable from ~12,200–11,900 cal BP and the ~10,400 BP 14C plateau is approximately 5 decades too short. The new kauri record and repositioned NH pine 14C series offer a refinement of the international 14C calibration curves IntCal13 and SHCal13, providing increased confidence in the correlation of global paleorecords.
Monozygotic (MZ) twinning is generally considered to be rare in species other than human. We inspected sex ratios in European zoo-bred ring-tailed lemurs (Lemur catta), revealing a significant excess of same-sex twins. Of 94 pairs, 60 (64%) were either both males or both females (p = .004). Application of the Weinberg differential rule argues that 27% of all twins in this species are MZ pairs. In this protected species, where twinning is commonplace (~50% of newborns are twins), the probable existence of frequent MZ twinning has ramifications for breeding programs aimed to maximize genetic diversity, and suggests that twin studies in a species other than human could have potential as a medical research tool.
To examine the use of vitamin D supplements during infancy among the participants in an international infant feeding trial.
Information about vitamin D supplementation was collected through a validated FFQ at the age of 2 weeks and monthly between the ages of 1 month and 6 months.
Infants (n 2159) with a biological family member affected by type 1 diabetes and with increased human leucocyte antigen-conferred susceptibility to type 1 diabetes from twelve European countries, the USA, Canada and Australia.
Daily use of vitamin D supplements was common during the first 6 months of life in Northern and Central Europe (>80 % of the infants), with somewhat lower rates observed in Southern Europe (>60 %). In Canada, vitamin D supplementation was more common among exclusively breast-fed than other infants (e.g. 71 % v. 44 % at 6 months of age). Less than 2 % of infants in the USA and Australia received any vitamin D supplementation. Higher gestational age, older maternal age and longer maternal education were study-wide associated with greater use of vitamin D supplements.
Most of the infants received vitamin D supplements during the first 6 months of life in the European countries, whereas in Canada only half and in the USA and Australia very few were given supplementation.
We present first imaging results from the PALM-3000 adaptive optics system and PHARO camera on the Hale 5 m telescope. Observations using a vector vortex coronagraph have given us direct detections of the two-ring dusty debris system around the star HD 141569. Our observations reveal the inner clearing in the disk to unprecedentedly small angular separations, and are the most sensitive yet at the H and K bands. We are for the first time able to measure and compare the colors of the scattered light in the inner and outer dust rings, and find that the outer ring is significantly bluer than the inner ring.
Wc describe here the New Zealand kauri (Agathis australis) Younger Dryas (YD) research project, which aims to undertake Δ14C analysis of ∼140 decadal floating wood samples spanning the time interval ∼13.1–11.7 kyr cal BP. We report 14C intercomparison measurements being undertaken by the carbon dating laboratories at University of Waikato (Wk), University of California at Irvine (UCI), and University of Oxford (OxA). The Wk, UCI, and OxA laboratories show very good agreement with an interlaboratory comparison of 12 successive decadal kauri samples (average offsets from consensus values of –7 to +4 14C yr). A University of Waikato/University of Heidelberg (HD) intercomparison involving measurement of the YD-age Swiss larch tree Ollon505, shows a HD/Wk offset of ∼10–20 14C yr (HD younger), and strong evidence that the positioning of the Ollon505 series is incorrect, with a recommendation that the 14C analyses be removed from the IntCal calibration database.
In most practices, sonohysterography is immediately preceded by high-frequency transvaginal sonography (TVS). Exact menstrual dating and latex allergy are documented first, and a negative pregnancy test is obtained, along with a signed informed consent, when appropriate. The purpose of the baseline ultrasound is to confirm all pelvic findings prior to the fluid enhancement study. Although sonohysterography provides an indirect look inside the uterus, its ability to accurately diagnose intracavitary filling defects, such as myomas and polyps and adhesions and even malformations, matches that of the gold standard hysteroscopy. This chapter lists out specific imaging examples for submucous myoma, endometrial polyp, blood clot, endometrial malignancy, intrauterine synechia and congenital uterine anomaly. It outlines three-dimensional saline infusion sonohysterography (SIS), sonosalpingography or hysterosalpingo-contrast sonography, operative SIS, and sonovaginography. Combining TVS with vaginal saline infusion may improve the ability to image structures surrounding the vagina, such as the rectovaginal septum for endometriosis.
Muscle contractile and metabolic characteristics were studied on nine cloned and eight non-cloned (control) heifers. The animals were submitted to repeated biopsies of the semitendinosus (ST) muscle at the ages of 8, 12, 18 and 24 months. The contractile type was determined from the proportion of the different myosin heavy chain (MyHC) isoforms separated by electrophoresis. Glycolytic metabolism was assessed by lactate dehydrogenase (LDH) activity, and oxidative metabolism was assessed by isocitrate dehydrogenase (ICDH), cytochrome-c oxidase (COX) and β-hydroxyacyl-CoA dehydrogenase (HAD) activities. In cloned heifers at 8 months of age, there was a greater proportion of MyHC I (slow oxidative isoform) and MyHC IIa (fast oxido-glycolytic isoform), a lower proportion of MyHC IIx (fast glycolytic isoform), greater COX and HAD activity and a lower LDH/ICDH ratio compared with control heifers. Thus, young cloned heifers had slower muscle types associated with a more oxidative muscular metabolism than control heifers. From 12 months of age onwards, no significant differences were observed between cloned and control heifers. A delay in muscle differentiation and maturation in cloned heifers is hypothesised and discussed.
Ultrasound (US) measurement of the endometrium is now an indispensable part of ovulation induction monitoring and assisted reproductive technologies (ART). This chapter describes the use of US in the evaluation of infertility and monitoring ovulation induction for ART and for relations or artificial insemination. It discusses the critical US values for ovulation induction (OI) and in vitro fertilization (IVF). Endometrial Pattern, endometrial thickness, and endometrial waves are evaluated. On statistical analysis, biochemical pregnancies were significantly related to endometrial thickness and pattern and were unrelated to maternal age or number of previous spontaneous abortions. For optimal pregnancy and birth results, endometrial thickness should be 9 mm or thicker on, at the time of spontaneous luteinizing hormone (LH) surge, or when human chorionic gonadotropin (hCG) is administered, OI cycles for relations or intrauterine insemination (IUI) and when hCG is administered in IVF cycles.
Clomiphene revolutionized the management of infertility in 1967 when it was approved for treatment of anovulation due to polycystic ovaries (PCO). The pharmacokinetics and pharmacodynamics of clomiphene explain its characteristic actions. After ovulation induction with clomiphene, serum progesterone and estradiol serum levels are increased during the luteal phase of the cycle in a direct dose-response relationship. Ultrasound of the ovaries should always be performed before initiating clomiphene treatment for the first time to rule out preexisting ovarian neoplasm, endometriomas, and persistent corpus luteum cysts to evaluate the number and size of antral follicles. Progesterone is used to confirm ovulation to determine if the dose of clomiphene is sufficient. Pregnancy rates may be increased in clomiphene cycles by increasing the number of follicles that develop, by improving endometrial conditions and cervical mucus, and by intrauterine insemination (IUI) when numbers of sperm on a postcoital test are low or absent.
Ovulation induction (OI) that is not part of an in vitro fertilization (IVF) cycle is the cause of 40-70 percent of high-order multiple pregnancies (HOMP), pregnancies with three or more conceptus, and 11-21 percent of twins, in countries where modern infertility treatment is practiced. Clomiphene Citrate (CC) increases follicular stimulation hormone (FSH) secretion from the pituitary by temporarily blocking the negative feedback of estrogen that is necessary to regulate production and secretion of FSH. Pulsatile gonadotropin-releasing hormone (GnRH) administered subcutaneously or intravenously results in pregnancy and multiple pregnancies similar to low-dose gonadotropins. A widely used technique for reducing HOMP during controlled ovarian hyperstimulation-intauterine insemination (COH-IUI) treatment is to withhold human chorionic gonadotropin (hCG) administration when excessive numbers of follicles or estradiol (E) concentrations are present. OI should not be attempted, and IVF should be used instead for women who cannot safely carry a twin pregnancy.