Metabolic acidosis in a lactating woman induced by a deliberate ketogenic diet.

ABSTRACT: This article describes a rare case of lactation ketoacidosis in a patient who started a ketogenic diet while nursing an infant and toddler. The patient presented to the ED with a history of nausea, vomiting, and postural dizziness, and was found to have a significant metabolic acidosis and elevated lipase level. The metabolic changes induced in this patient could occur in anyone with high metabolic demands who also is on a strict ketogenic diet. The case highlights the importance of a dietary history in patients with unexplained metabolic derangements

Co-binding by YY1 identifies the transcriptionally active, highly conserved set of CTCF-bound regions in primate genomes.

BACKGROUND: The genomic binding of CTCF is highly conserved across mammals, but the mechanisms that underlie its stability are poorly understood. One transcription factor known to functionally interact with CTCF in the context of X-chromosome inactivation is the ubiquitously expressed YY1. Because combinatorial transcription factor binding can contribute to the evolutionary stabilization of regulatory regions, we tested whether YY1 and CTCF co-binding could in part account for conservation of CTCF binding. RESULTS: Combined analysis of CTCF and YY1 binding in lymphoblastoid cell lines from seven primates, as well as in mouse and human livers, reveals extensive genome-wide co-localization specifically at evolutionarily stable CTCF-bound regions. CTCF-YY1 co-bound regions resemble regions bound by YY1 alone, as they enrich for active histone marks, RNA polymerase II and transcription factor binding. Although these highly conserved, transcriptionally active CTCF-YY1 co-bound regions are often promoter-proximal, gene-distal regions show similar molecular features. CONCLUSIONS: Our results reveal that these two ubiquitously expressed, multi-functional zinc-finger proteins collaborate in functionally active regions to stabilize one another's genome-wide binding across primate evolution

Latent regulatory potential of human-specific repetitive elements

At least half of the human genome is derived from repetitive elements, which are often lineage specific and silenced by a variety of genetic and epigenetic mechanisms. Using a transchromosomic mouse strain that transmits an almost complete single copy of human chromosome 21 via the female germline, we show that a heterologous regulatory environment can transcriptionally activate transposon-derived human regulatory regions. In the mouse nucleus, hundreds of locations on human chromosome 21 newly associate with activating histone modifications in both somatic and germline tissues, and influence the gene expression of nearby transcripts. These regions are enriched with primate and human lineage-specific transposable elements, and their activation corresponds to changes in DNA methylation at CpG dinucleotides. This study reveals the latent regulatory potential of the repetitive human genome and illustrates the species specificity of mechanisms that control it

Unexpectedly high concentrations of monoterpenes in a study of UK homes

The abundance of volatile organic compounds (VOCs) found in homes depends on many factors such as emissions, ventilation and the oxidative environment and these are evolving over time, reflecting changes in chemical use, behaviour and building design/materials. The concentrations of VOCs in 25 UK homes of varying ages, design and occupancy were quantified using continuous indoor air sampling over five days. Air was collected through low flow (1 mL min-1) constant flow restrictors into evacuated 6 L internally silica-treated canisters until the canisters reached atmospheric pressure. This was followed by thermal desorption-gas chromatography and high mass accuracy time-of-flight mass spectrometry (TD-GC-TOF/MS). A fully quantitative analysis was performed on the eight most abundant hydrocarbon-based VOCs found. Despite differences in building characteristics and occupant numbers 94% of the homes had d-limonene or α-pinene as the most abundant VOCs. The variability seen across the 25 homes in concentrations of monoterpenes indoors was considerably greater than that of species such as isoprene, benzene, toluene and xylenes. The variance in VOCs indoors appeared to be strongly influenced by occupant activities such as cleaning with 5-day average concentrations of d-limonene ranging from 18 μg m-3 to over 1400 μg m-3, a peak domestic value that is possibly the highest yet reported in the literature

Simulated Microgravity Regulates Gene Transcript Profiles of 2T3 Preosteoblasts: Comparison of the Random Positioning Machine and the Rotating Wall Vessel Bioreactor

Microgravity of spaceflight induces bone loss due in part to decreased bone formation by osteoblasts. We have previously examined the microgravity-induced changes in gene expression profiles in 2T3 preosteoblasts using the Random Positioning Machine (RPM) to simulate microgravity conditions. Here, we hypothesized that exposure of preosteoblasts to an independent microgravity simulator, the Rotating Wall Vessel (RWV), induces similar changes in differentiation and gene transcript profiles, resulting in a more confined list of gravi-sensitive genes that may play a role in bone formation. In comparison to static 1g controls, exposure of 2T3 cells to RWV for 3 days inhibited alkaline phosphatase activity, a marker of differentiation, and downregulated 61 genes and upregulated 45 genes by more than two-fold as shown by microarray analysis. The microarray results were confirmed with real time PCR for downregulated genes osteomodulin, bone morphogenic protein 4 (BMP4), runx2, and parathyroid hormone receptor 1. Western blot analysis validated the expression of three downregulated genes, BMP4, peroxiredoxin IV, and osteoglycin, and one upregulated gene peroxiredoxin I. Comparison of the microarrays from the RPM and the RWV studies identified 14 gravi-sensitive genes that changed in the same direction in both systems. Further comparison of our results to a published database showing gene transcript profiles of mechanically loaded mouse tibiae revealed 16 genes upregulated by the loading that were shown to be downregulated by RWV and RPM. These mechanosensitive genes identified by the comparative studies may provide novel insights into understanding the mechanisms regulating bone formation and potential targets of countermeasure against decreased bone formation both in astronauts and in general patients with musculoskeletal disorders

Research Communication Deregulated LAP2a Expression in Cervical Cancer Associates with Aberrant E2F and p53 Activities

Summary Lamina-associated polypeptide 2 alpha (LAP2a) plays a role in maintaining nuclear structure, in nuclear assembly/disassembly, and in transcriptional regulation. Elevated LAP2a mRNA expression has been previously reported to associate with certain cancer types. The aim of this study was to investigate LAP2a expression in cervical cancer and transformed cells and to identify factors that associate with its differential expression. LAP2a expression was found to be elevated in cervical cancer tissue by microarray, qRT-PCR, and immunofluorescence analyses. LAP2a also showed elevated expression in cervical cancer cell lines and in transformed fibroblasts compared with normal cells. To determine factors associated with elevated LAP2a in cervical cancer, the effect of inhibiting HPV E7 and E6 oncoproteins was investigated. E7 inhibition resulted in a decrease in phosphorylated Rb and an associated decrease in LAP2a, suggesting a role for E2F in regulating LAP2a expression. This finding was confirmed by inhibiting DP1, a coactivator of E2F, which resulted in decreased LAP2a levels. Inhibition of E6 resulted in elevated p53 and an associated decrease in LAP2a, suggesting that p53 associates with the negative regulation of LAP2a expression. This hypothesis was tested by inhibiting p53 in normal cells, and a resultant increase in LAP2a expression was observed. In conclusion, this study provides evidence for elevated LAP2a expression in cervical cancer and suggests that E2F and p53 activities associate with the positive and negative regulation of LAP2a expression, respectively. 2011 IUBMB IUBMB Life, 00: 000-000, 201

Explaining variable effects of an adaptable implementation package to promote evidence-based practice in primary care : a longitudinal process evaluation

This study is funded by the National Institute for Health Research (NIHR) [Programme Grants for Applied Research (Grant Reference Number RP-PG-1209-10040)] (https://www.nihr.ac.uk/).Background Implementing evidence-based recommendations is challenging in UK primary care, especially given system pressures and multiple guideline recommendations competing for attention. Implementation packages that can be adapted and hence applied to target multiple guideline recommendations could offer efficiencies for recommendations with common barriers to achievement. We developed and evaluated a package of evidence-based interventions (audit and feedback, educational outreach and reminders) incorporating behaviour change techniques to target common barriers, in two pragmatic trials for four “high impact” indicators: risky prescribing; diabetes control; blood pressure control; and anticoagulation in atrial fibrillation. We observed a significant, cost-effective reduction in risky prescribing but there was insufficient evidence of effect on the other outcomes. We explored the impact of the implementation package on both social processes (Normalisation Process Theory; NPT) and hypothesised determinants of behaviour (Theoretical Domains Framework; TDF). Methods We conducted a prospective multi-method process evaluation. Observational, administrative and interview data collection and analyses in eight primary care practices were guided by NPT and TDF. Survey data from trial and process evaluation practices explored fidelity. Results We observed three main patterns of variation in how practices responded to the implementation package. First, in integration and achievement, the package “worked” when it was considered distinctive and feasible. Timely feedback directed at specific behaviours enabled continuous goal setting, action and review, which reinforced motivation and collective action. Second, impacts on team-based determinants were limited, particularly when the complexity of clinical actions impeded progress. Third, there were delivery delays and unintended consequences. Delays in scheduling outreach further reduced ownership and time for improvement. Repeated stagnant or declining feedback that did not reflect effort undermined engagement. Conclusions Variable integration within practice routines and organisation of care, variable impacts on behavioural determinants, and delays in delivery and unintended consequences help explain the partial success of an adaptable package in primary care.Publisher PDFPeer reviewe