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Cellular nuisance compounds are a burden in chemical biology and drug screening. Here the authors profile prototypical cytotoxic and nuisance compounds using the cell painting assay to systematically characterise cellular morphologies associated with compound-dependent cellular injury and nuisance activity.

ING5 is a component of KAT6A and KAT7 histone lysine acetylation protein complexes. ING5 contains a PHD domain that binds to histone H3 lysine 4 when it is trimethylated, and so functions as a ‘reader’ and adaptor protein. KAT6A and KAT7 function are critical for normal hematopoiesis. To examine the function of ING5 in hematopoiesis, we generated a null allele of Ing5. Mice lacking ING5 during development had decreased foetal liver cellularity, decreased numbers of hematopoietic stem cells and perturbed erythropoiesis compared to wild-type control mice. Ing5–/– pups had hypoplastic spleens. Competitive transplantation experiments using foetal liver hematopoietic cells showed that there was no defect in long-term repopulating capacity of stem cells lacking ING5, suggesting that the defects during the foetal stage were not cell intrinsic. Together, these results suggest that ING5 function is dispensable for normal hematopoiesis but may be required for timely foetal hematopoiesis in a cell-extrinsic manner.

Abstract Histone acetylation is essential for initiating and maintaining a permissive chromatin conformation and gene transcription. Dysregulation of histone acetylation can contribute to tumorigenesis and metastasis. Using inducible cre-recombinase and CRISPR/Cas9-mediated deletion, we investigated the roles of the histone lysine acetyltransferase TIP60 (KAT5/HTATIP) in human cells, mouse cells, and mouse embryos. We found that loss of TIP60 caused complete cell growth arrest. In the absence of TIP60, chromosomes failed to align in a metaphase plate during mitosis. In some TIP60 deleted cells, endoreplication occurred instead. In contrast, cell survival was not affected. Remarkably, the cell growth arrest caused by loss of TIP60 was independent of the tumor suppressors p53, INK4A and ARF. TIP60 was found to be essential for the acetylation of H2AZ, specifically at lysine 7. The mRNA levels of 6236 human and 8238 mouse genes, including many metabolism genes, were dependent on TIP60. Among the top 50 differentially expressed genes, over 90% were downregulated in cells lacking TIP60, supporting a role for TIP60 as a key co-activator of transcription. We propose a primary role of TIP60 in H2AZ lysine 7 acetylation and transcriptional activation, and that this fundamental role is essential for cell proliferation. Growth arrest independent of major tumor suppressors suggests TIP60 as a potential anti-cancer drug target.

Summary: In the conventional model of transcriptional activation, transcription factors bind to response elements and recruit co-factors, including histone acetyltransferases. Contrary to this model, we show that the histone acetyltransferase KAT7 (HBO1/MYST2) is required genome wide for histone H3 lysine 14 acetylation (H3K14ac). Examining neural stem cells, we find that KAT7 and H3K14ac are present not only at transcribed genes but also at inactive genes, intergenic regions, and in heterochromatin. KAT7 and H3K14ac were not required for the continued transcription of genes that were actively transcribed at the time of loss of KAT7 but indispensable for the activation of repressed genes. The absence of KAT7 abrogates neural stem cell plasticity, diverse differentiation pathways, and cerebral cortex development. Re-expression of KAT7 restored stem cell developmental potential. Overexpression of KAT7 enhanced neuron and oligodendrocyte differentiation. Our data suggest that KAT7 prepares chromatin for transcriptional activation and is a prerequisite for gene activation.

Acetylation of histone H3K23 has emerged as an essential posttranslational modification, yet this epigenetic mark remains poorly understood. Here, the authors identify the native MORF complex as a histone H3K23-specific acetyltransferase and show that interaction of the MORF subunit with acylated H3K14 promotes acetylation of H3K23 by this complex to activate transcription.

Summary: Understanding the mechanisms of activity-dependent gene transcription underlying adaptive behaviors is challenging at neuronal-subtype resolution. Using cell-type specific molecular analysis in agouti-related peptide (AgRP) neurons, we reveal that the profound hunger-induced transcriptional changes greatly depend on plant homeodomain finger protein 6 (PHF6), a transcriptional repressor enriched in AgRP neurons. Loss of PHF6 in the satiated mice results in a hunger-state-shifting transcriptional profile, while hunger fails to further induce a rapid and robust activity-dependent gene transcription in PHF6-deficient AgRP neurons. We reveal that PHF6 binds to the promoters of a subset of immediate-early genes (IEGs) and that this chromatin binding is dynamically regulated by hunger state. Depletion of PHF6 decreases hunger-driven feeding motivation and makes the mice resistant to body weight gain under repetitive fasting-refeeding conditions. Our work identifies a neuronal subtype-specific transcriptional repressor that modulates transcriptional profiles in different nutritional states and enables adaptive eating behavior. : Gan et al. show that PHF6 is a transcriptional repressor enriched in AgRP neurons and regulates immediate-early gene (IEG) expression. Depletion of PHF6 in AgRP neurons decreases hunger-driven feeding motivation and makes the mice resistant to body weight gain under repetitive fasting/refeeding conditions. Keywords: PHF6, hunger-driven feeding behavior, AgRP neuron, activity-dependent gene transcription, immediate-early genes, IEGs, Börjeson-Forssman-Lehmann syndrome, BFLS

Background and Aims: Bag mask ventilation (BMV) allows for oxygenation and ventilation of patients until a definitive airway is secured and when definitive airway is difficult/impossible. This study hypothesised that the EO (thumb and index finger form a O shape around the mask) technique of mask holding provides better mask seal with the novices compared to the classic EC clamp technique (thumb and index finger form a C shape around the mask). Methods: Sixty patients participated in this double blinded, prospective, crossover study. The patients were randomly allocated to either EC or EO group. After adequate anaesthesia and neuromuscular blockade, a novice (experience of less than five attempts at BMV) held the mask with preferred hand with the allotted technique, while the ventilator provided five breaths at set pressure control of 15 cm H2O with one second each for inspiration and expiration. After recording the exhaled tidal volume (primary objective) for each breath for five consecutive breaths, the study was repeated with the other technique. Secondary outcome variables were minute ventilation, audible mask and epigastric leak. Results: The tidal volume and minute ventilation were significantly better with EO technique compared with the EC technique (P = 0.001, a tidal volume difference of 46 mL and P = 0.001, a minute volume difference of 0.51 L). Conclusion: The EO technique provides better mask seal (superior tidal volumes) than the conventional EC technique during single-handed mask holding performed by novices in the absence of other factors contributing to difficulty in mask ventilation.

Summary: Neural tube defects (NTDs) are common birth defects in humans and show an unexplained female bias. Female mice lacking the tumor suppressor p53 display NTDs with incomplete penetrance. We found that the combined loss of pro-apoptotic BIM and p53 caused 100% penetrant, female-exclusive NTDs, which allowed us to investigate the female-specific functions of p53. We report that female p53−/− embryonic neural tube samples show fewer cells with inactive X chromosome markers Xist and H3K27me3 and a concomitant increase in biallelic expression of the X-linked genes, Huwe1 and Usp9x. Decreased Xist and increased X-linked gene expression was confirmed by RNA sequencing. Moreover, we found that p53 directly bound response elements in the X chromosome inactivation center (XIC). Together, these findings suggest p53 directly activates XIC genes, without which there is stochastic failure in X chromosome inactivation, and that X chromosome inactivation failure may underlie the female bias in neural tube closure defects. : The molecular mechanisms underlying the female bias of neural tube defects are currently unclear. Delbridge et al. present evidence that p53 is required for normal Xist expression and X chromosome inactivation and show in two models that partial failure of X chromosome inactivation is associated with female-biased neural tube defects. Keywords: female-specific neural tube defects, X-chromosome inactivation, p53, Xist, Ftx, Tsix, biallelic expression, BIM, BCL2L11, SMCHD1

How functionally diverse populations of pathogen-specific killer T cells are generated during an immune response remains unclear. Here, we propose that fine-tuning of CD8αβ co-receptor levels via histone acetylation plays a role in lineage fate. We show that lysine acetyltransferase 6A (KAT6A) is responsible for maintaining permissive Cd8 gene transcription and enabling robust effector responses during infection. KAT6A-deficient CD8+ T cells downregulated surface CD8 co-receptor expression during clonal expansion, a finding linked to reduced Cd8α transcripts and histone-H3 lysine 9 acetylation of the Cd8 locus. Loss of CD8 expression in KAT6A-deficient T cells correlated with reduced TCR signaling intensity and accelerated contraction of the effector-like memory compartment, whereas the long-lived memory compartment appeared unaffected, a result phenocopied by the removal of the Cd8 E8I enhancer element. These findings suggest a direct role of CD8αβ co-receptor expression and histone acetylation in shaping functional diversity within the cytotoxic T cell pool.

The Ts1Cje mouse model of Down syndrome (DS) has partial trisomy of mouse chromosome 16 (MMU16), which is syntenic to human chromosome 21 (HSA21). It develops various neuropathological features demonstrated by DS patients such as reduced cerebellar volume [1] and altered hippocampus-dependent learning and memory [2,3]. To understand the global gene expression effect of the partially triplicated MMU16 segment on mouse brain development, we performed the spatiotemporal transcriptome analysis of Ts1Cje and disomic control cerebral cortex, cerebellum and hippocampus harvested at four developmental time-points: postnatal day (P)1, P15, P30 and P84. Here, we provide a detailed description of the experimental and analysis procedures of the microarray dataset, which has been deposited in the Gene Expression Omnibus (GSE49050) database.

Background and Aims : Utility of gabapentin for pre-operative anxiolysis as compared to commonly administered alprazolam is not evident. The aim of the present study was to compare the effects of pre-operative oral gabapentin 600 mg, alprazolam 0.5 mg or a placebo on pre-operative anxiety along with post-operative pain and morphine consumption. Methods: Seventy five patients scheduled for abdominal hysterectomy under general anaesthesia were included. Groups gabapentin, alprazolam and placebo, received oral gabapentin 600 mg, alprazolam 0.5 mg and one capsule of oral B-complex forte with Vitamin C respectively, on the night prior to surgery and 2 h prior to surgery. Visual analogue scale (VAS) was used to measure the anxiety and post-operative pain. All patients received patient-controlled analgesia. Statistical tests used were Kruskal-Wallis test, Wilcoxon signed rank test and one-way ANOVA. Results: Alprazolam provided significant anxiolysis (median [interquartile range] baseline VAS score 35 [15.5, 52] to 20 [6.5, 34.5] after drug administration; P = 0.007). Gabapentin did not provide significant decrease in anxiety (median [interquartile range] VAS score 21 [7.5, 41] to 20 [6.5, 34.5]; P = 0.782). First analgesic request time (median [interquartile range in minutes]) was longer in group gabapentin (17.5 [10, 41.25]) compared to group placebo (10 [5, 15]) (P = 0.019) but comparable to that in group alprazolam (15 [10, 30]). Cumulative morphine consumption at different time periods and total morphine consumption (mean [standard deviation]) at the end of study period (38.65 [18.04], 39.91 [15.73], 44.29 [16.02] mg in group gabapentin, alprazolam and placebo respectively) were comparable. Conclusion: Gabapentin 600 mg does not have significant anxiolytic effect compared to alprazolam 0.5 mg. Alprazolam 0.5 mg was found to be an effective anxiolytic in the pre-operative period. Neither alprazolam nor gabapentin, when compared to placebo showed any opioid sparing effects post-operatively.

Takayasu′s arteritis (TA) is rare, chronic progressive, pan-endarteritis involving the aorta and its main branches, with a specific predilection for young Asian women. Anaesthesia for TA patients is complicated by their severe uncontrolled hypertension, extreme arterial blood pressure differentials, aortic regurgitation (AR), end-organ dysfunction, stenosis/aneurysms of major blood vessels and difficulties encountered in monitoring arterial blood pressure. We present the usefulness of ultrasound during anaesthetic management of a 35-year-old woman posted for emergency caesarean section due to intra-uterine growth retardation, foetal tachycardia in active labour, who was already diagnosed to have TA along with moderate AR and uncontrolled hypertension, using epidural technique. The use of intra-operative doppler helped resolve the initial dilemma about the diagnosis and treatment of the differential blood pressure between the affected and the normal upper limb in the absence of prior arteriogram.

Pheochromocytoma is a rare neuroendocrine tumor of childhood. We present a 14-year-old boy with bilateral pheochromocytoma, post nephrectomy in view of a non-functioning kidney presenting with severe hypertension and end organ damage. Diagnosis was confirmed with 24-hour urinary VMA, catechol amines, and CT scan. Preoperative blood pressure (BP) was controlled with prazosin, propranolol, nicardipine, and HCT-spironolactone. Anesthesia was given with general endotracheal anesthesia with epidural analgesia. Intraoperative BP rise was managed with infusion of NTG, MgSO4, esmolol, and dexmedetomidine which was especially challenging on account of bilateral tumor.

Escobar syndrome is a rare autosomal recessive disorder characterized by flexion joint and digit contractures, skin webbing, cleft palate, deformity of spine and cervical spine fusion. Associated difficult airway is mainly due to micrognathia, retrognathia, webbing of neck and limitation of the mouth opening and neck extension. We report a case of a 1 year old child with Escobar syndrome posted for bilateral hamstrings to quadriceps transfer. The child had adequate mouth opening with no evidence of cervical spine fusion, yet we faced difficulty in intubation which was ultimately overcome by securing a proseal laryngeal mask airway (PLMA) and then by intubating with an endotracheal tube railroaded over a paediatric fibreoptic bronchoscope passed through the lumen of a PLMA.

PLOS ONE Volume 8 includes an article "The First New Zealanders: Patterns of Diet and Mobility Revealed through Isotope Analysis". The paper proposes that burial groups within the settlement phase site of Wairau Bar differ in terms of dietary stable isotopes and 87Sr/86Sr. The authors argue this difference is probably due to one group being a founding population while the other burials are later. Here we review the work of Kinaston et al. and present an alternative analysis and interpretation of the isotopic data. Treating the isotope data independently from cultural and biological factors we find that sex best explains dietary variation. Our reassessment of 87Sr/86Sr confirms the authors original finding of high mobility of early New Zealanders but suggests a larger range of individuals should be considered 'non-local' on current evidence.

Posterior reversible encephalopathy syndrome (PRES) is a cliniconeuroradiological syndrome associated with various clinical conditions, presenting with headache, encephalopathy, seizures, cortical visual disturbances or blindness. Imaging predominantly shows parieto-occipital white matter changes, with vasogenic oedema being the most accepted pathophysiology. We report a 25-year-old primigravida who presented in term pregnancy with seizures and blindness, scheduled for emergency caesarean section. She was managed peroperatively under general anaesthesia and shifted to intensive care unit. Postoperative computed tomography brain revealed an intra-axial hypodensity involving predominantly white matter regions of bilateral parieto-occipital lobes, right caudate nucleus and right cerebellum, suggestive of PRES. Clinical improvement with complete resolution of visual disturbances was observed with supportive treatment. The importance of prompt suspicion and management in preventing short- and long-term neurological deficits in reversible condition like PRES is highlighted.

BackgroundDown syndrome (DS) individuals suffer mental retardation with further cognitive decline and early onset Alzheimer's disease.Methodology/principal findingsTo understand how trisomy 21 causes these neurological abnormalities we investigated changes in gene expression networks combined with a systematic cell lineage analysis of adult neurogenesis using the Ts1Cje mouse model of DS. We demonstrated down regulation of a number of key genes involved in proliferation and cell cycle progression including Mcm7, Brca2, Prim1, Cenpo and Aurka in trisomic neurospheres. We found that trisomy did not affect the number of adult neural stem cells but resulted in reduced numbers of neural progenitors and neuroblasts. Analysis of differentiating adult Ts1Cje neural progenitors showed a severe reduction in numbers of neurons produced with a tendency for less elaborate neurites, whilst the numbers of astrocytes was increased.Conclusions/significanceWe have shown that trisomy affects a number of elements of adult neurogenesis likely to result in a progressive pathogenesis and consequently providing the potential for the development of therapies to slow progression of, or even ameliorate the neuronal deficits suffered by DS individuals.