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Omega-6 fatty acids have been shown to exert pro-adipogenic effects whereas omega-3 fatty acids work in opposition. Increasing intakes of LA (linoleic acid; omega-6) vs ALA (alpha-linolenic acid; omega-3) in Western diets has led to the hypothesis that consumption of this diet during pregnancy may be contributing to adverse offspring health. This study investigated the effects of feeding a maternal dietary LA:ALA ratio similar to that of the Western diet (9:1) compared to a proposed ‘ideal’ ratio (~1:1.5), at two total fat levels (18% vs 36% fat w/w), on growth and lipogenic gene expression in the offspring. Female Wistar rats were assigned to one of the four experimental groups throughout gestation and lactation. Offspring were culled at 1 and 2 weeks of age for sample collection. Offspring of dams consuming a -36% fat diet were ~20% lighter than those exposed to a 18% fat diet (P<0.001). Male, but not female, liver weight at 1 week was ~13% heavier, and had increased glycogen (P<0.05), in offspring exposed to high LA (P<0.01). Hepatic expression of lipogenic genes suggested an increase in lipogenesis in male offspring exposed to a 36% fat maternal diet and in female offspring exposed to a low LA diet, via increases in the expression of Fasn and Srebf1. Sexually dimorphic responses to altered maternal diet appeared to persist until two weeks-of-age. In conclusion, whilst maternal total fat content predominantly affected offspring growth, fatty acid ratio and total fat content had sexually dimorphic effects on offspring liver weight and composition.
Enterococcus causes clinically significant bloodstream infections (BSIs). In centers with a higher prevalence of vancomycin resistant enterococcus (VRE) colonization, a common clinical question is whether empiric treatment directed against VRE should be initiated in the setting of a suspected enterococcal BSI. Unfortunately, VRE treatment options are limited, and relatively expensive, and subject patients to the risk of adverse reactions. We hypothesized that the results of VRE colonization screening could predict vancomycin resistance in enterococcal BSI.
We reviewed 370 consecutive cases of enterococcal BSI over a 7-year period at 2 tertiary-care hospitals to determine whether vancomycin-resistant BSIs could be predicted based on known colonization status (ie, patients with swabs performed within 30 days, more remotely, or never tested). We calculated sensitivity and specificity, and we plotted negative predictives values (NPVs) and positive predictive values (PPVs) as a function of prevalence.
A negative screening swab within 30 days of infection yielded NPVs of 90% and 95% in settings where <27.0% and 15.0% of enterococcal BSI are resistant to vancomycin, respectively. In patients with known VRE colonization, the PPV for VRE in enterococcal BSI was >50% at any prevalence exceeding 25%.
The results of a negative VRE screening test result performed within 30 days can help eliminate unnecessary empiric therapy in patients with suspected enterococcal BSI. Conversely, patients with positive VRE screening swabs require careful consideration of empiric VRE-directed therapy when enterococcal BSI appears likely.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
The common femoral artery is a continuation of the external iliac artery and is approximately 4 cm long. It begins directly behind the inguinal ligament, midway between the anterior superior iliac spine and the symphysis pubis.
The profunda femoris artery arises from the lateral aspect of the common femoral artery, towards the femur, approximately 3–4 cm below the inguinal ligament. The common femoral artery continues obliquely down the anteromedial aspect of the thigh as the superficial femoral artery.
The superficial femoral artery exits the femoral triangle to enter the subsartorial canal and ends by passing through an opening in the adductor magnus to become the popliteal artery.
In the upper third of the thigh, the femoral vessels are contained within the femoral triangle (Scarpa’s triangle).
The femoral triangle is formed laterally by the medial border of the sartorius muscle, medially by the adductor longus, and superiorly by the inguinal ligament.
In the femoral triangle, the femoral vein lies medial to the femoral artery. The greater saphenous vein drains into the femoral vein about 3–4 cm below the inguinal ligament; further distally, the femoral vein lies posterior to the artery and maintains this relationship in the popliteal fossa. The femoral nerve and its branches are found lateral to the common femoral artery.
In the middle third of the thigh, the femoral artery lies within the adductor canal (Hunter’s canal), an aponeurotic tunnel in the middle third of the thigh that extends from the apex of the femoral triangle to the opening in the adductor magnus.
The adductor canal is bounded by the sartorius muscle anteriorly, the vastus medialis laterally, and the adductor longus and magnus posteromedially. A fascial plane between the vastus medialis and adductor longus and magnus covers the canal.
The canal contains the femoral artery and vein, the saphenous nerve which crosses from lateral to medial, and branches of the femoral nerve.
The femoral vein courses from a medial position in the groin to a posterior and then lateral position with respect to the artery as it moves distally towards the knee.
The greater saphenous vein courses medially to lie on the anterior surface of the thigh, before entering the fascia lata and joining the common femoral vein at the sapheno-femoral junction near the femoral triangle.
Financial network structure is an important determinant of systemic risk. This article examines how the U.S. interbank network evolved over a long and important period that included two key events: the founding of the Federal Reserve and the Great Depression. Banks established connections to correspondents that joined the Federal Reserve in cities with Fed offices, initially reducing overall network concentration. The network became even more focused on Fed cities during the Depression, as survival rates were higher for banks with more existing connections to Fed cities, and as survivors established new connections to those cities over time.
Ichthyosporean parasites (order Dermocystida) can cause morbidity and mortality in amphibians, but their ecology and epidemiology remain understudied. We investigated the prevalence, gross and histologic appearance, and molecular phylogeny of a novel dermocystid in the state-endangered silvery salamander (Ambystoma platineum) and the co-occurring, non-threatened small-mouthed salamander (Ambystoma texanum) from Illinois. Silvery salamanders (N = 610) were sampled at six ephemeral wetlands from 2016 to 2018. Beginning in 2017, 1–3 mm raised, white skin nodules were identified in 24 silvery salamanders and two small-mouthed salamanders from five wetlands (prevalence = 0–11.1%). Skin biopsy histology (N = 4) was consistent with dermocystid sporangia, and necropsies (N = 3) identified infrequent hepatic sporangia. Parasitic 18S rRNA sequences (N = 5) from both salamander species were identical, and phylogenetic analysis revealed a close relationship to Dermotheca viridescens. Dermocystids were not identified in museum specimens from the same wetlands (N = 125) dating back to 1973. This is the first report of Dermotheca sp. affecting caudates in the Midwestern United States. Future research is needed to determine the effects of this pathogen on individual and population health, and to assess whether this organism poses a threat to the conservation of ambystomatid salamanders.
This chapter, reviews the basics for children undergoing epilepsy surgery. The authors discuss the incidence and types of seizures as well as various modalities for seizure suppression (e.g. ketogenic diet, vagal nerve stimulation). The chapter presents the surgical approaches to epilepsy surgery, MRI mapping followed by laser ablation and electrocorticography with mapping followed by surgical excision. The anesthetic implications related to these complex patients are presented.
This essay examines the colonial relationship between the Anglican Church and the British Empire's Welsh subjects across the nineteenth century. Focusing on the small output of a group of exiled Welsh clergymen (known as The Association of Welsh Clergy in the West Riding of the County of York), I consider Welsh Anglican responses to the church's neglect of Wales (exemplified by no Welsh-speaking bishop being assigned to a Welsh diocese between 1727 and 1870, despite the majority of the population not speaking English). The association believed that preaching in a foreign language such as English constituted a perversion from proper church practice and that this both reflected hegemonic attitudes toward indigenous and non-English speaking populations and pushed the Welsh population toward dissent. In response, the association sought to combine church reform with Welsh nationalism by elevating Welsh speakers as the spiritual inheritors of the true and primitive British church. They promulgated their visions in annual reports published between 1852 and 1856 into which they channeled other contemporary voices speaking against tyrannical and “Romish” Anglican Church practices. Through an analysis of post-Reformation Welsh church histories and the reports’ usages of such terminology as “alienation,” “Catholicism,” and “patriotism,” I reveal how the Welsh national identity the association fashioned at once operated within and aspired to correct the Anglican Church.
We state Breuillard, Green and Tao’s rough classification of the finite approximate subgroups of an arbitrary group. This states that a finite approximate subgroup of an arbitrary group is contained in a union of a few cosets of a finite-by-nilpotent group, the nilpotent quotient of which has bounded step. We define coset nilprogressions, and show how to deduce a more detailed version of the Breuillard–Green–Tao theorem in which the approximate subgroup is contained in a union of a few translates of a coset nilprogression of bounded rank and step.
We prove Tointon’s theorem that a finite approximate subgroup of a residually nilpotent group is contained in a union of a few cosets of a finite-by-nilpotent group in which the nilpotent quotient is of bounded step. We first prove it in the special case in which G is nilpotent of unbounded step, and finish the chapter by showing how to extend this to the general residually nilpotent case. As part of the proof we show that if a nilpotent group G is a central extension of a finite approximate group A then the commutator subgroup of G is contained in a bounded power of A. We also show that if A is an approximate subgroup of a nilpotent group then a large piece of A can be written as a bounded series of some bounded extensions and some central extensions.
We present Green and Ruzsa’s proof of Freiman’s theorem in an arbitrary abelian group. More specifically, we show that a finite set A of small doubling inside an abelian group is contained in a relatively small coset progression of bounded rank. We introduce the basics of discrete Fourier analysis, and how it relates to sets of small doubling. We prove the Green–Ruzsa result that a set of small doubling in an arbitrary abelian group has a Freiman model in a relatively small finite abelian group. We then prove Bogolyubov’s lemma that a small iterated sum set of this model must contain a relatively large Bohr set of low rank. Combined with the material of the previous chapter, this shows that A contains a relatively large coset progression of low rank. We then deduce the main theorem of the chapter using Chang’s covering argument. In the exercises we guide the reader to a simpler version of the argument yielding the same result in the special case in which A is a set of integers.
We motivate the definitions of sets of small doubling and approximate groups, and introduce their basic properties. We show that random sets of integers (suitably defined) have large expected doubling. We prove Freiman’s theorem that a subset of a group of doubling less than 2/3 is close to a finite subgroup. We prove the Plünnecke–Ruzsa inequalities, Ruzsa’s triangle inequality and Ruzsa’s covering lemma. We motivate in detail the definition of an approximate group, and reduce the study of sets of small doubling to the study of finite approximate groups. We show that the notions of small tripling and approximate group are stable under intersections and group homomorphisms. We introduce Freiman homomorphisms and present their basic properties.
We prove Breuillard and Green’s theorem that a finite approximate subgroup of a soluble complex linear group G of bounded degree is contained in a union of a few cosets of a nilpotent group of bounded step. We first treat the special case in which G is an upper-triangular group. An important ingredient is Solymosi’s sum-product theorem over the complex numbers, which we state and prove. We introduce some basic representation theory and use it to prove that a soluble complex linear group of bounded degree has a subgroup of bounded index that is conjugate to an upper-triangular group; this is a special case of a result of Mal’cev. We then use this to extend from the upper-triangular case to the general soluble case.
We present Breuillard, Green and Tao’s theorem that a finite approximate subgroup of a complex linear group of bounded degree is contained in a union of a few cosets of a nilpotent subgroup of bounded step. We state two substantial ingredients without proof. The first is a result of Mal’cev and Platinov that a virtually soluble complex linear group of bounded degree has a soluble subgroup of bounded index. The second is Breuillard’s uniform Tits alternative, which states that if a finitely generated complex linear group of bounded degree is not virtually soluble then there exist two free generators of a free subgroup that can be expressed as products of boundedly many generators. The third main ingredient is a result, due independently to Sanders and to Croot and Sisask, that if A is an arbitrary approximate group then there is a relatively large neighbourhood of the identity S with the property that a large power of S is contained in a small power of A; we prove this in full.