Electrocardiographic (ECG) criteria for determining left ventricular mass in young healthy men; data from the LARGE Heart study

Background: Doubts remain over the use of the ECG in identifying those with increased left ventricular (LV) mass. This is especially so in young individuals, despite their high prevalence of ECG criteria for LV hypertrophy. We performed a study using cardiovascular magnetic resonance (CMR), which provides an in vivo non-invasive gold standard method of measuring LV mass, allowing accurate assessment of electrocardiography as a tool for defining LV hypertrophy in the young.Methods and results: Standard 12-lead ECGs were obtained from 101 Caucasian male army recruits aged (mean +/- SEM) 19.7 +/- 0.2 years. LV mass was measured using CMR. LV mass indexed to body surface area demonstrated no significant correlation with the Cornell Amplitude criteria or Cornell Product for LV hypertrophy. Moderate correlations were seen with the Sokolow-Lyon Amplitude (0.28) and Sokolow-Lyon Product (0.284). Defining LV hypertrophy as a body surface area indexed left ventricular mass of 93 g/m(2), calculated sensitivities [and specificities] were as follows; 38.7% [74.3%] for the Sokolow-Lyon criteria, 43.4% [61.4%] for the Sokolow-Lyon Product, 19.4% [91.4%] for Cornell Amplitude, and 22.6% [85.7%] for Cornell Product. These values are substantially less than those reported for older age groups.Conclusion: ECG criteria for LV hypertrophy may have little value in determining LV mass or the presence of LV hypertrophy in young fit males

Cybersecurity, Technology, and Society: Developing an Interdisciplinary, Open, General Education Cybersecurity Course

This paper describes an interdisciplinary effort involving faculty from five different disciplines who came together to develop an interdisciplinary, open, general education cybersecurity course. The course, Cybersecurity, Technology, and Society, brings together ideas from interdisciplinary studies, information technology, engineering, business, computer science, criminal justice, and philosophy to provide students an interdisciplinary introduction to cybersecurity. We provide an overview of the rationale for the course, the process the authors went through developing the course, a summary of the course modules, details about the open education resources used as readings, and the types of assignments included in the class. We conclude by offering recommendations for others developing similar courses

Improved protocols for functional analysis in the pathogenic fungus Aspergillus flavus

<p>Abstract</p> <p>Background</p> <p>An available whole genome sequence for <it>Aspergillus flavus </it>provides the opportunity to characterize factors involved in pathogenicity and to elucidate the regulatory networks involved in aflatoxin biosynthesis. Functional analysis of genes within the genome is greatly facilitated by the ability to disrupt or mis-express target genes and then evaluate their result on the phenotype of the fungus. Large-scale functional analysis requires an efficient genetic transformation system and the ability to readily select transformants with altered expression, and usually requires generation of double (or multi) gene deletion strains or the use of prototrophic strains. However, dominant selectable markers, an efficient transformation system and an efficient screening system for transformants in <it>A. flavus </it>are absent.</p> <p>Results</p> <p>The efficiency of the genetic transformation system for <it>A. flavus </it>based on uracil auxotrophy was improved. In addition, <it>A. flavus </it>was shown to be sensitive to the antibiotic, phleomycin. Transformation of <it>A. flavus </it>with the <it>ble </it>gene for resistance to phleomycin resulted in stable transformants when selected on 100 μg/ml phleomycin. We also compared the phleomycin system with one based on complementation for uracil auxotrophy which was confirmed by uracil and 5-fluoroorotic acid selection and via transformation with the <it>pyr4 </it>gene from <it>Neurospora crassa </it>and <it>pyrG </it>gene from <it>A. nidulans </it>in <it>A. flavus </it>NRRL 3357. A transformation protocol using <it>pyr4 </it>as a selectable marker resulted in site specific disruption of a target gene. A rapid and convenient colony PCR method for screening genetically altered transformants was also developed in this study.</p> <p>Conclusion</p> <p>We employed phleomycin resistance as a new positive selectable marker for genetic transformation of <it>A. flavus</it>. The experiments outlined herein constitute the first report of the use of the antibiotic phleomycin for transformation of <it>A. flavus</it>. Further, we demonstrated that this transformation protocol could be used for directed gene disruption in <it>A. flavus</it>. The significance of this is twofold. First, it allows strains to be transformed without having to generate an auxotrophic mutation, which is time consuming and may result in undesirable mutations. Second, this protocol allows for double gene knockouts when used in conjunction with existing strains with auxotrophic mutations.</p> <p>To further facilitate functional analysis in this strain we developed a colony PCR-based method that is a rapid and convenient method for screening genetically altered transformants. This work will be of interest to those working on molecular biology of aflatoxin metabolism in <it>A. flavus</it>, especially for functional analysis using gene deletion and gene expression.</p

Use of stereotypical mutational motifs to define resolution limits for the ultra-deep resequencing of mitochondrial DNA.

Massively parallel resequencing of mitochondrial DNA (mtDNA) has led to significant advances in the study of heteroplasmic mtDNA variants in health and disease, but confident resolution of very low-level variants ( C, from patient with MNGIE, mitochondrial neurogastrointestinal encephalomyopathy) and comparing mutational pattern distribution with healthy mtDNA by ligation-mediated deep resequencing (Applied Biosystems SOLiD). We empirically derived mtDNA-mutant heteroplasmy detection limits, demonstrating that the presence of stereotypical mutational motif could be statistically validated for heteroplasmy thresholds ≥ 0.22% (P = 0.034). We therefore provide empirical evidence from biological samples that very low-level mtDNA mutants can be meaningfully resolved by massively parallel resequencing, confirming the utility of the approach for studying somatic mtDNA mutation in health and disease. Our approach could also usefully be employed in other settings to derive platform-specific deep resequencing resolution limits

Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies.

Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin-converting enzyme (ACE) is the central component of endocrine and local tissue renin-angiotensin systems (RAS), which also regulate diverse aspects of whole-body metabolism and mitochondrial function (partly through altering mitochondrial UCP expression). We show that ACE expression also appears to be regulated by mitochondrial UCPs. In genetic analysis of two unrelated populations (healthy young UK men and Scandinavian diabetic patients) serum ACE (sACE) activity was significantly higher amongst UCP3-55C (rather than T) and UCP2 I (rather than D) allele carriers. RNA interference against UCP2 in human umbilical vein endothelial cells reduced UCP2 mRNA sixfold (P < 0·01) whilst increasing ACE expression within a physiological range (<1·8-fold at 48 h; P < 0·01). Our findings suggest novel hypotheses. Firstly, cellular feedback regulation may occur between UCPs and ACE. Secondly, cellular UCP regulation of sACE suggests a novel means of crosstalk between (and mutual regulation of) cellular and endocrine metabolism. This might partly explain the reduced risk of developing diabetes and metabolic syndrome with RAS antagonists and offer insight into the origins of cardiovascular disease in which UCPs and ACE both play a role

Recognition and Accommodation at the Androgen Receptor Coactivator Binding Interface

Prostate cancer is a leading killer of men in the industrialized world. Underlying this disease is the aberrant action of the androgen receptor (AR). AR is distinguished from other nuclear receptors in that after hormone binding, it preferentially responds to a specialized set of coactivators bearing aromatic-rich motifs, while responding poorly to coactivators bearing the leucine-rich “NR box” motifs favored by other nuclear receptors. Under normal conditions, interactions with these AR-specific coactivators through aromatic-rich motifs underlie targeted gene transcription. However, during prostate cancer, abnormal association with such coactivators, as well as with coactivators containing canonical leucine-rich motifs, promotes disease progression. To understand the paradox of this unusual selectivity, we have derived a complete set of peptide motifs that interact with AR using phage display. Binding affinities were measured for a selected set of these peptides and their interactions with AR determined by X-ray crystallography. Structures of AR in complex with FxxLF, LxxLL, FxxLW, WxxLF, WxxVW, FxxFF, and FxxYF motifs reveal a changing surface of the AR coactivator binding interface that permits accommodation of both AR-specific aromatic-rich motifs and canonical leucine-rich motifs. Induced fit provides perfect mating of the motifs representing the known family of AR coactivators and suggests a framework for the design of AR coactivator antagonists

Spectral Theory for Perturbed Krein Laplacians in Nonsmooth Domains

We study spectral properties for $H_{K,\Omega}$, the Krein--von Neumann extension of the perturbed Laplacian $-\Delta+V$ defined on $C^\infty_0(\Omega)$, where $V$ is measurable, bounded and nonnegative, in a bounded open set $\Omega\subset\mathbb{R}^n$ belonging to a class of nonsmooth domains which contains all convex domains, along with all domains of class $C^{1,r}$, $r>1/2$. In particular, in the aforementioned context we establish the Weyl asymptotic formula #\{j\in\mathbb{N} | \lambda_{K,\Omega,j}\leq\lambda\} = (2\pi)^{-n} v_n |\Omega| \lambda^{n/2}+O\big(\lambda^{(n-(1/2))/2}\big) {as} \lambda\to\infty, where $v_n=\pi^{n/2}/ \Gamma((n/2)+1)$ denotes the volume of the unit ball in $\mathbb{R}^n$, and $\lambda_{K,\Omega,j}$, $j\in\mathbb{N}$, are the non-zero eigenvalues of $H_{K,\Omega}$, listed in increasing order according to their multiplicities. We prove this formula by showing that the perturbed Krein Laplacian (i.e., the Krein--von Neumann extension of $-\Delta+V$ defined on $C^\infty_0(\Omega)$) is spectrally equivalent to the buckling of a clamped plate problem, and using an abstract result of Kozlov from the mid 1980's. Our work builds on that of Grubb in the early 1980's, who has considered similar issues for elliptic operators in smooth domains, and shows that the question posed by Alonso and Simon in 1980 pertaining to the validity of the above Weyl asymptotic formula continues to have an affirmative answer in this nonsmooth setting.Comment: 60 page

Chronic Kidney Disease in Cats and the Risk of Total Hypercalcemia

BACKGROUND: Chronic kidney disease (CKD) is a common comorbidity in cats with hypercalcemia, but whether CKD is a risk factor for hypercalcemia is unclear. Hypercalcemia often is diagnosed based on total calcium concentration (tCa), which tends to underestimate the ionized calcium concentration (iCa) in cats. OBJECTIVES: Assessment of the performance of tCa for the diagnosis of ionized hypercalcemia, and exploration of factors influencing the relationship between iCa and tCa. Determination of risk factors for incident total hypercalcemia (ie, the development of hypercalcemia based on tCa during follow‐up). ANIMALS: Records of a cross‐section (n = 477) and observational cohort (n = 367) of client‐owned cats with and without azotemic CKD from first opinion practice. METHODS: Retrospective cross‐sectional and retrospective cohort study. The diagnostic accuracy of tCa as an index test for ionized hypercalcemia was evaluated, and risk factors for underestimation were explored by binary logistic and linear regression in a cross‐section of cats with and without azotemic CKD. Chronic kidney disease and clinicopathological variables were assessed as predictors of incident total hypercalcemia by both time‐invariant and time‐dependent Cox regression in a cohort of cats. RESULTS: Specificity of tCa for identification of ionized hypercalcemia was high (100%), but sensitivity was low. Underestimation was associated with lower venous bicarbonate concentrations. Cats with CKD had increased risk for incident total hypercalcemia (hazard ratio, 4.29; 95% confidence interval, 1.96–9.37; P < .001). Higher tCa predicted incident total hypercalcemia in both azotemic and nonazotemic cats (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Chronic kidney disease is a risk factor for incident total hypercalcemia, and most cats with increased tCa had concurrent ionized hypercalcemia. Higher baseline tCa predicts incident total hypercalcemia. Prospective studies assessing changes in iCa are warranted

Acupuncture for cancer pain in adults.

BACKGROUND: Forty percent of individuals with early or intermediate stage cancer and 90% with advanced cancer have moderate to severe pain and up to 70% of patients with cancer pain do not receive adequate pain relief. It has been claimed that acupuncture has a role in management of cancer pain and guidelines exist for treatment of cancer pain with acupuncture. OBJECTIVES: To evaluate efficacy of acupuncture for relief of cancer-related pain in adults. SEARCH STRATEGY: CENTRAL, MEDLINE, EMBASE, PsycINFO, AMED, and SPORTDiscus were searched up to November 2010 including non-English language papers. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating any type of invasive acupuncture for pain directly related to cancer in adults of 18 years or over. DATA COLLECTION AND ANALYSIS: It was planned to pool data to provide an overall measure of effect and to calculate the number needed to treat to benefit, but this was not possible due to heterogeneity. Two review authors (CP, OT) independently extracted data adding it to data extraction sheets. Quality scores were given to studies. Data sheets were compared and discussed with a third review author (MJ) who acted as arbiter. Data analysis was conducted by CP, OT and MJ. MAIN RESULTS: Three RCTs (204 participants) were included. One high quality study investigated the effect of auricular acupuncture compared with auricular acupuncture at 'placebo' points and with non-invasive vaccaria ear seeds attached at 'placebo' points. Participants in two acupuncture groups were blinded but blinding wasn't possible in the ear seeds group because seeds were attached using tape. This may have biased results in favour of acupuncture groups. Participants in the real acupuncture group had lower pain scores at two month follow-up than either the placebo or ear seeds group.There was high risk of bias in two studies because of low methodological quality. One study comparing acupuncture with medication concluded that both methods were effective in controlling pain, although acupuncture was the most effective. The second study compared acupuncture, point-injection and medication in participants with stomach cancer. Long-term pain relief was reported for both acupuncture and point-injection compared with medication during the last 10 days of treatment. Although both studies have positive results in favour of acupuncture they should be viewed with caution due to methodological limitations, small sample sizes, poor reporting and inadequate analysis. AUTHORS' CONCLUSIONS: There is insufficient evidence to judge whether acupuncture is effective in treating cancer pain in adults