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White adipocytes are key regulators of metabolic homeostasis, which release stored energy as free fatty acids via lipolysis. Adipocytes possess both basal and stimulated lipolytic capacity, but limited information exists regarding the molecular mechanisms that regulate basal lipolysis. Here, we describe a mechanism whereby autocrine purinergic signalling and constitutive P2Y2 receptor activation suppresses basal lipolysis in primary human in vitro-differentiated adipocytes. We found that human adipocytes possess cytoplasmic Ca2+ tone due to ATP secretion and constitutive P2Y2 receptor activation. Pharmacological antagonism or knockdown of P2Y2 receptors increases intracellular cAMP levels and enhances basal lipolysis. P2Y2 receptor antagonism works synergistically with phosphodiesterase inhibitors in elevating basal lipolysis, but is dependent upon adenylate cyclase activity. Mechanistically, we suggest that the increased Ca2+ tone exerts an anti-lipolytic effect by suppression of Ca2+-sensitive adenylate cyclase isoforms. We also observed that acute enhancement of basal lipolysis following P2Y2 receptor antagonism alters the profile of secreted adipokines leading to longer-term adaptive decreases in basal lipolysis. Our findings demonstrate that basal lipolysis and adipokine secretion are controlled by autocrine purinergic signalling in human adipocytes. [ABSTRACT FROM AUTHOR]

The regulatory landscape related to building control in Australia is complex. While there is a single performance based technical requirement in common for building work there are eight state and territory governments and the commonwealth government, each with a different legislative framework for dealing with development activities. Each has adopted some form of private participation model. In the view of AIBS, Australian government structures and policy implementation with respect to building control is not working. In September 2017, AIBS released a Policy: 'Building Regulatory Reform in Australia', a document describing a legislative framework, which has the capacity to deal with emergent issues such as non-conforming building products in a way that supports the benefits of private participation. This paper sets out why and how AIBS has developed its policy, the policy content and how the content interrelates to other elements of the legislative landscape. It describes the importance of elements in supporting the successful implementation of a performance based technical code and how this will support the competitiveness of Australia's economy. It also provides the integral components for a robust building control system that supports a sustainable building industry providing better outcomes for consumers and industry. [ABSTRACT FROM AUTHOR]

Leukocytes sense extracellular ATP, a danger-associated molecular pattern, released during cellular stress and death, via activation of cell surface P2X and P2Y receptors. Here, we investigate P2 receptor expression in primary human monocyte-derived macrophages and receptors that mediate ATP-evoked intracellular [Ca2+]i signals and cytokine production in response to ATP concentrations that exclude P2X7 receptor activation. Expression of P2X1, P2X4, P2X5, P2X7, P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, and P2Y13 was confirmed by quantitative RT-PCR and immunocytochemistry. ATP elicited intracellular Ca2+ responses in a concentration-dependent fashion (EC50 = 11.4 6 2.9 mM, n = 3). P2Y11 and P2Y13 activations mediated the amplitude of [Ca2+]i response, whereas P2X4 activation, but not P2X1 or P2X7, determined the duration of Ca2+ response during a sustained phase. ATP mediated gene induction of CXCL5, a proinflammatory chemokine. P2X4 antagonism (PSB-12062 or BX430) inhibited ATPmediated induction of CXCL5 gene expression and secretion of CXCL5 by primary macrophage. Inhibition of CXCL5 secretion by P2X4 antagonists was lost in the absence of extracellular Ca2+. Reciprocally, positive allosteric modulation of P2X4 (ivermectin) augmented ATP-mediated CXCL5 secretion. P2X7, P2Y11, or P2Y13 receptor did not contribute to CXCL5 secretion. Together, the data reveals a role for P2X4 in determining the duration of ATP-evoked Ca2+ responses and CXCL5 secretion in human primary macrophage. [ABSTRACT FROM AUTHOR]

Hypercalcaemia is a common disorder normally caused by primary hyperparathyroidism (PHPT) or malignancy. A proportion of cases present as an emergency, which carries a significant mortality. Emergency management of hypercalcaemia is based on intravenous rehydration with normal saline but when this is inadequate, bisphosphonate therapy is used; more recently the novel anti-resorbtive agent denosumab has been shown to have a useful role in treatment. It is estimated that up to 10% of all cases of PHPT presenting under the age of 45 years have an underlying genetic predisposition; nine potentially causative genes are now recognised and may be screened in routine clinical practice. Although parathyroidectomy is the only curative treatment for PHPT, this is indicated in a minority of cases. Many cases can be adequately managed conservatively and guidance from the 4th international workshop on the management of asymptomatic PHPT has recently been updated in a consensus statement. [ABSTRACT FROM AUTHOR]

Fischer Brown Norway (FBN) rats (n = 233) were unilaterally exposed to 12 different combinations of noise intensity, duration, and spectrum, while 46 rats served as sham-exposed controls. Rats were behaviorally tested for tinnitus and hyperacusis using gap-induced inhibition of the acoustic startle reflex (Gap) and prepulse inhibition (PPI) using 60-dB SPL before noise-exposure and at regular intervals for 12 mo. 12-mo after noise exposure the middle-aged rats were then tested again for tinnitus and hyperacusis before collecting Auditory Brainstem Response (ABR) thresholds. Collapsing across all noise exposure conditions a significant tinnitus-like deficit in responding to silent gaps was observed, with the most likely tinnitus pitch around 16 kHz. Rates of tinnitus 12-mo after noise exposure were greatest in groups receiving the four least intense noise doses (110-dB for 30, 60 and 120 min, and 116-dB for 30 min), while some of the greatest rates of hyperacusis occurred in groups receiving more intense or longer exposures. The results suggest that rates for developing tinnitus in animal models may not be easily predicted based upon noise exposure dose, but that low-to-moderate noise exposures may result in the greatest likelihood for producing tinnitus. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests a role for inhibitory neurotransmitter dysfunction in the pathology of tinnitus. Opposing hypotheses proposed either a pathologic decrease or increase of GABAergic inhibition in medial geniculate body (MGB). In thalamus,GABAmediates fast synaptic inhibition via synaptic GABAA receptors (GABAARs) and persistent tonic inhibition via high-affinity extrasynaptic GABAARs. Given that extrasynaptic GABAARs control the firing mode of thalamocortical neurons, we examined tonic GABAAR currents inMGBneurons in vitro, using the following three groups of adult rats: unexposed control (Ctrl); sound exposed with behavioral evidence of tinnitus (Tin); and sound exposed with no behavioral evidence of tinnitus (Non-T). Tonic GABAAR currents were evoked using the selective agonist gaboxadol. Months after a tinnitus-inducing sound exposure, gaboxadol-evoked tonic GABAAR currents showed significant tinnitus-related increases contralateral to the sound exposure. In situ hybridization studies found increased mRNA levels for GABAAR δ-subunits contralateral to the sound exposure. Tin rats showed significant increases in the number of spikes per burst evoked using suprathreshold-injected current steps. In summary, we found little evidence of tinnitus-related decreases in GABAergic neurotransmission. Tinnitus and chronic pain may reflect thalamocortical dysrhythmia, which results from abnormal theta-range resonant interactions between thalamus and cortex, due to neuronal hyperpolarization and the initiation of low-threshold calcium spike bursts (Walton and Llina's, 2010). In agreement with this hypothesis, we found tinnitus-related increases in tonic extrasynaptic GABAAR currents, in action potentials/evoked bursts, and in GABAAR δ-subunit gene expression. These tinnitus-related changes in GABAergic function may be markers for tinnitus pathology in the MGB. [ABSTRACT FROM AUTHOR]

Flavoprotein autofluorescence imaging was used to examine auditory cortical synaptic responses in aged animals with behavioral evidence of tinnitus and hearing loss. Mice were exposed to noise trauma at 1 -3 months of age and were assessed for behavioral evidence of tinnitus and hearing loss immediately after the noise trauma and again at --24-30 months of age. Within 2 months of the final behavioral assessment, auditory cortical synaptic transmission was examined in brain slices using electrical stimulation of putative thalamocortical afférents, and flavoprotein autofluorescence imaging was used to measure cortical activation. Noise-exposed animals showed a 68% increase in amplitude of cortical activation compared with controls (p = 0.008), and these animals showed a diminished sensitivity to GABAAergic blockade (p = 0.008, using bath-applied 200nΜ SR 95531 [6-Imino-3-(4-methoxyphenyl)-l(6H)-p yridazinebutanoic acid hydrobromide] ). The strength of cortical activation was significantly correlated to the degree of tinnitus behavior, assessed via a loss of gap detection in a startle paradigm. The decrease in GABAA sensitivity was greater in the regions of the cortex farther away from the stimulation site, potentially reflecting a greater sensitivity of corticocortical versus thalamocortical projections to the effects of noise trauma. Finally, there was no relationship between auditory cortical activation and activation of the somatosensory cortex in the same slices, suggesting that the increases in auditory cortical activation were not attributable to a generalized hyperexcitable state in noise-exposed animals. These data suggest that noise trauma can cause long-lasting changes in the auditory cortical physiology and may provide specific targets to ameliorate the effects of chronic tinnitus. [ABSTRACT FROM AUTHOR]

Abstract: Presbycusis can be considered a slow age-related peripheral and central deterioration of auditory function which manifests itself as deficits in speech comprehension, especially in noisy environments. The present study examined neural correlates of a simple broadband noise stimulus in primary auditory cortex (A1) of young and aged Fischer–Brown Norway (FBN) rats. Age-related changes in unit responses to broadband noise bursts and spontaneous activity were simultaneously recorded across A1 layers using a single shank, 16-channel electrode. Noise bursts were presented contralateral to the left A1 at 80dB SPL. Aged A1 units displayed increased spontaneous (29%), peak (24%), and steady state response rates (38%) than did young A1 units. This was true across all A1 layers, although age-related differences were significantly greater for layers I–III (43% vs 18%) than lower layers. There was a significant age-related difference in the depth and duration of post-onset suppression between young and aged upper layer A1 units. The present functional differences across layers were consistent with studies showing greatest losses of gamma-aminobutyric acid (GABA) markers in superficial layers of A1 and with anatomic studies showing highest levels of inhibitory neurons located in superficial cortical layers. The present findings were also consistent with aging studies suggesting loss of functional inhibition in other cortical sensory systems. [Copyright &y& Elsevier]

Abstract: Aims: The type 2 muscarinic receptor (M2R) differs from the other G-protein-coupled muscarinic receptor (type 4, or M4R) in tissue distribution and physiologic effects. We studied the impact of these receptors on sleep and arousal by using M2R and M4R knock-out (KO) mice. Main methods: M2R and M4R KO and genetically intact mice were compared in terms of normal patterns of sleep, responses to sleep loss, infectious challenge and acoustic startle, and acoustic prepulse inhibition of startle (PPI). Key findings: Under basal conditions, M2R and M4R KO mice do not differ from the background strain or each other in the amount or diurnal pattern of sleep, locomotor activity, and body temperature. After enforced sleep loss, M2R KO mice, in contrast to the other two strains, show no rebound in slow-wave sleep (SWS) time, although their SWS is consolidated, and they show a greater rebound in time spent in REMS (rapid-eye-movement sleep) and REMS consolidation. During influenza infection, M2R KO mice, as compared with the other strains, show marked hypothermia and a less robust increase in SWS. During Candida albicans infection, M2R KO mice show a greater increase in SWS and a greater inflammatory response than do the other strains. M2R KO mice also show greater acoustic startle amplitude than does the background strain, although PPI was not different across the 3 strains over a range of stimulus intensities. Significance: Taken together, these findings support different roles for M2R and M4R in the modulation of sleep and arousal during homeostatic challenge. [Copyright &y& Elsevier]

An iterative approach is developed for decoding Space Time Trellis Codes (STTCs) in frequently selective Multiple Input Multiple Output (MIMO) channels. The method uses the Partitioned Viterbi Algorithm (PVA) as an equaliser for the MIMO system. It is used iteratively with a STTC decoder that provides soft outputs using the Soft Output Viterbi Algorithm (SOVA). It is shown through simulation that the iterative procedure achieves a performance within 2.0dB of Maximum Likelihood (ML) decoding, at a FER of 10-2, but suffers a small diversity loss. It is also shown that the complexity of the iterative approach is lower than that of ML decoding. [ABSTRACT FROM AUTHOR]

Purpose: A variety of options for behavioral assessment of tinnitus in laboratory animals are available to researchers today. These options are briefly reviewed, followed by data suggesting that gap detection procedures might be used to efficiently measure acute, salicylate-induced tinnitus and possibly hyperacusis in rats. Method: Fischer Brown Norway rats (n = 10) were given intraperitoneal injections of 350 mg/kg sodium salicylate on 2 consecutive days, and the effects on gap detection were observed across 9 different frequency bands. Pretest, posttest, and washout data were collected. An additional 4 rats were each given 4 different doses of sodium salicylate (0, 150, 250, and 300 mg/kg), and gap detection and prepulse inhibition were measured. Results: Significant gap detection deficits were observed from pre- to posttest that were consistent with tinnitus. Consistent gap detection deficits were found using broadband noise backgrounds, while significant improvements in responding to frequency-specific test bands were found. Similar effects were repeated in the dose response portion of the study. Conclusions: Gap detection procedures efficiently measured salicylate-induced changes in behavior that were consistent with the presence of tinnitus. In addition, the reliable, stronger responses at many frequencies after salicylate injections suggest the possibility of measuring a hyperacusis-like phenomenon using these methods. [ABSTRACT FROM AUTHOR]

The study describes a novel method for tinnitus screening in rats by use of gap detection reflex procedures. The authors hypothesized that if a background acoustic signal was qualitatively similar to the rat's tinnitus, poorer detection of a silent gap in the background would be expected, Rats with prior evidence of tinnitus at 10 kHz (n = 14) exhibited significantly worse gap detection than controls (n = 13) when the gap was embedded in a background similar to their tinnitus. No differences between tinnitus and control rats were found with 16 kHz or broadband noise backgrounds, which helped to rule out explanations related to hearing loss or general performance deficits. The results suggest that gap detection reflex procedures might be effective for rapid tinnitus screening in rats. [ABSTRACT FROM AUTHOR]

Abstract: Layer-V pyramidal cells comprise a major output of primary auditory cortex (A1). At least two cell types displaying different morphology, projections and in vitro physiology have been previously identified in layer-V. The focus of the present study was to characterize extracellular receptive field properties of layer-V neurons to determine whether a similar breakdown of responses can be found in vivo. Recordings from 105 layer-V neurons revealed two predominant receptive field types. Thirty-two percent displayed strong excitatory V/U-shaped receptive field maps and spiking patterns with shorter stimulus-driven interspike intervals (ISIs), reminiscent of the bursting cells discussed in the in vitro literature. V/U-shaped maps remained relatively unchanged across the three sequential repetitions of the map run on each neuron. Neurons with V/U-shaped maps were also easily depolarized with extracellular current pulse stimulation. In contrast, 47% of the neurons displayed Complex receptive field maps characterized by weak and/or inconsistent excitatory regions and were difficult to depolarize with current pulses. These findings suggest that V/U-shaped receptive fields could correspond to previously described intrinsic bursting (IB) cells with corticotectal projections, and that neurons with Complex receptive fields might represent the regular spiking (RS) cells with their greater inhibitory input and corticocortical/corticostriatal projection pattern. [Copyright &y& Elsevier]

Reports that the LIM protein FHL3 binds basic Kruppel-like factor/Kruppel-like factor 3 and its co-processor C-terminal-binding protein 2. Evidence that CtBP2 interacts with FHL3; Demonstration that the proteins co-elute in gel filtration experiments; Importance of LIM proteins like FHL3 in assembling specific repression or activation complexes.

Discusses the enzymatic activity and influence of the C-terminal Binding Protein (CtBP) in gene expression. Discovery of the CtBP; Role of the CtBP on Pro-X-Asp-Leu-Ser motifs in DNA-binding proteins; Recruitment of histone deacetylase enzymes in gene expression; Evidence on the role of CtBP proteins in gene transcription and Golgi function.

Focuses on a study which showed that GC-type elements play important roles in the control of tissue-specific genes as well as ubiquitously expressed genes and that the transcription factor SP1 is a member of an extensive family of factors. Features of the SP1 family; Differences within the family; Discussion on the results of the study.

Basic Krüppel-like factor (BKLF) is a zinc finger protein that recognizes CACCC elements in DNA. It is expressed highly in erythroid tissues, the brain and other selected cell types. We have studied the activity of BKLF and found that it is capable of repressing transcription, and have mapped its repression domain to the N-terminus. We carried out a two-hybrid screen against BKLF and isolated a novel clone encoding murine C-terminal-binding protein 2 (mCtBP2). mCtBP2 is related to human CtBP, a cellular protein which binds to a Pro-X-Asp-Leu-Ser motif in the C-terminus of the adenoviral oncoprotein, E1a. We show that mCtBP2 recognizes a related motif in the minimal repression domain of BKLF, and the integrity of this motif is required for repression activity. Moreover, when tethered to a promoter by a heterologous DNA-binding domain, mCtBP2 functions as a potent repressor. Finally, we demonstrate that mCtBP2 also interacts with the mammalian transcripition factors Evi-1, AREB6, ZEB and FOG. These results establish a new member of the CtBP family, mCtBP2, as a mammalian co-repressor targeting diverse transcriptional regulators. [ABSTRACT FROM AUTHOR]

Measuring tinnitus in laboratory animals is difficult, involving weeks or months of operant training. Preliminary data suggest that rapid screening for tinnitus in rats can be accomplished using an unconditioned acoustic startle reflex. In control animals, a gap in an otherwise constant acoustic background inhibits a subsequent startle response to a sound impulse. If, however, the background signal is qualitatively similar to the animal’s tinnitus, poorer detection of the gap and less inhibition of the startle might be expected. Fourteen animals with putative tinnitus at 10 kHz and 13 control animals were tested for gap detection using three different background signals: broadband noise, and filtered bandpass noise centered either at 16 kHz (15.5–16.5 kHz) or at their suspected tinnitus locus of 10 kHz (9.5–10.5 kHz). As predicted, animals with evidence of tinnitus exhibited significantly worse gap detection at 10 kHz, and were not significantly different than control animals at 16 kHz and broadband noise. These results suggest a new methodology for rapidly detecting tinnitus in individual animals. Equipment donated by Hamilton-Kinder Inc Behavioral Testing Systems in the memory of SIU graduate Dorothy Jean Kinder (Walker). [Work supported by NIH grants AG023910-01 (JT), DC4830 (TB & CB), and DC00151 (DC).] [ABSTRACT FROM AUTHOR]

Objectives: Individuals with chronic hypoparathyroidism may experience suboptimal medical care with high frequency of unplanned hospitalisation and iatrogenic harm. In 2015 the European Society for Endocrinology published consensus guidelines on the management of chronic hypoparathyroidism. We set out to audit compliance with these guidelines. Methods: Using these recommendations as audit standards we worked with the Society for Endocrinology and Parathyroid UK to conduct a national audit of management of chronic hypoparathyroidism in the United Kingdom. Endocrine leads in 117 endocrine departments were invited to participate in the survey by completing a data collection tool on up to 5 sequential cases of chronic hypoparathyroidism seen in their outpatient clinics in the preceding 12 months. Data were collected on 4 treatment standards and 9 monitoring standards. Data on hospitalisations and Quality of Life monitoring were also collected. Results: Responses were received from 22 departments giving a response rate of 19%, concerning 80 individual cases. The mean age of subjects was 48.4 years. The main findings were that the commonest cause of hypoparathyroidism was post surgical (66.3%). Treatments taken by the group included activated vitamin D analogues (96.3%), oral calcium salts (66.3%), vitamin D supplements (17.5%), thiazide diuretics (5%) and rhPTH1–34 (1.3%). Compliance with the audit standards varied between 98.8% and 60% for the treatment standards and between 91.3% and 20% for the monitoring standards. Some of the areas of weakness revealed include low rates of 24 h urinary calcium excretion monitoring, serum magnesium monitoring and low rates of renal imaging where indicated. In addition and importantly, 16.3% of subjects had experienced at least one hospital admission in the preceding 12 months. Conclusion: We conclude that further improvements in the UK national standard of management of chronic hypoparathyroidism should be made and that this will benefit both quality of life, morbidity and potentially mortality in this group of patients. [ABSTRACT FROM AUTHOR]

Tinnitus is an auditory percept without an environmental acoustic correlate. Contemporary tinnitus models hypothesize tinnitus to be a consequence of maladaptive plasticity-induced disturbance of excitation-inhibition homeostasis, possibly convergent onmedial geniculate body (MGB, auditory thalamus) and related neuronal networks. The MGB is an obligate acoustic relay in a unique position to gate auditory signals to higher-order auditory and limbic centres. Tinnitus-related maladaptive plastic changes of MGB-related neuronal networks may affect the gating function of MGB and enhance gain in central auditory and non-auditory neuronal networks, resulting in tinnitus. The present study examined the discharge properties of MGB neurons in the sound-exposure gap inhibition animal model of tinnitus. MGB single unit responses were obtained from awake unexposed controls and sound-exposed adult rats with behavioural evidence of tinnitus. MGB units in animals with tinnitus exhibited enhanced spontaneous firing, altered burst properties and increased rate-level function slope when driven by broadband noise and tones at the unit's characteristic frequency. Elevated patterns of neuronal activity and altered bursting showed a significant positive correlation with animals' tinnitus scores. Altered activity of MGB neurons revealed additional features of auditory system plasticity associated with tinnitus, whichmay provide a testable assay for future therapeutic and diagnostic development. [ABSTRACT FROM AUTHOR]

Familial benign hypocalciuric hypercalcaemia (FBHH) is a genetically heterogeneous disorder that consists of three designated types, FBHH1, FBHH2 and FBHH3, whose chromosomal locations are 3q21.1, 19p and 19q13, respectively. FBHH1 is caused by mutations of a calcium-sensing receptor (CaSR), but the abnormalities underlying FBHH2 and FBHH3 are unknown. FBHH3, also referred to as the Oklahoma variant (FBHHOk), has been mapped to a 12cM interval, flanked by D19S908 and D19S866. To refine the location of FBHH3, we pursued linkage studies using 24 polymorphic loci. Our results establish a linkage between FBHH3 and 17 of these loci, and indicate that FBHH3 is located in a 4.1 Mb region flanked centromerically by D19S112 and telomerically by rs245111, which in the syntenic region on mouse chromosome 7 contains four Casr-related sequences (Gprc2a-rss). However, human homologues of these Gprc2a-rss were not found and a comparative analysis of the 22.0 Mb human and 39.3 Mb mouse syntenic regions showed evolutionary conservation of two segments that were inverted with loss from the human genome of 11.6 Mb that contained the four Gprc2a-rss. Thus, FBHH3 cannot be attributed to Gprc2a-rss abnormalities. DNA sequence analysis of 12 other genes from the interval that were expressed in the parathyroids and/or kidneys did not detect any abnormalities, thereby indicating that these genes are unlikely to be the cause of FBHH3. The results of this study have refined the map location of FBHH3, which will facilitate the identification of another CaSR or a mediator of calcium homeostasis. [ABSTRACT FROM AUTHOR]

Aging and acoustic trauma may result in partial peripheral deafferentation in the central auditory pathway of the mammalian brain. In accord with homeostatic plasticity, loss of sensory input results in a change in pre- and postsynaptic GABAergic and glycinergic inhibitory neurotransmission. As seen in development, age-related changes may be activity dependent. Age-related presynaptic changes in the cochlear nucleus include reduced glycine levels, while in the auditory midbrain and cortex, GABA synthesis and release are altered. Presumably, in response to age-related decreases in presynaptic release of inhibitory neurotransmitters, there are age-related postsynaptic subunit changes in the composition of the glycine (GlyR) and GABAA (GABAAR) receptors. Age-related changes in the subunit makeup of inhibitory pentameric receptor constructs result in altered pharmacological and physiological responses consistent with a net down-regulation of functional inhibition. Age-related functional changes associated with glycine neurotransmission in dorsal cochlear nucleus (DCN) include altered intensity and temporal coding by DCN projection neurons. Loss of synaptic inhibition in the superior olivary complex (SOC) and the inferior colliculus (IC) likely affect the ability of aged animals to localize sounds in their natural environment. Age-related postsynaptic GABAAR changes in IC and primary auditory cortex (Al) involve changes in the subunit makeup of GABAARs. In turn, these changes cause age-related changes in the pharmacology and response properties of neurons in IC and Al circuits, which collectively may affect temporal processing and response reliability. Findings of age-related inhibitory changes within mammalian auditory circuits are similar to age and deafferentation plasticity changes observed in other sensory systems. Although few studies have examined sensory aging in the wild, these age-related changes would likely compromise an animal's ability to avoid predation or to be a successful predator in their natural environment. [ABSTRACT FROM AUTHOR]

Small ubiquitin-like modifier (SUMO) is a protein moiety that is ligated to lysine residues on a variety of target proteins. Many known SUMO substrates are transcription factors or coregulators of transcription, and in most cases, modification with SUMO leads to the attenuation of transcriptional activation. We have examined basic Krüppel-like factor/Krüppel-like factor 3 (BKLF), a zinc finger transcription factor that is known to function as a potent transcriptional repressor. We show that BKLF recruits the E2 SUMOconjugating enzyme Ubc9 and can be modified by the addition of SUMO-1 in vitro and in vivo. The SUMO E3 ligases PIAS1, PIASγ, PIASxα, and PIASxβ but not Pc2 enhance the sumoylation of BKLF. Site-directed mutagenesis identified two lysines (K10 and K197) of BKLF as the sumoylation sites. Sumoylation does not detectably affect DNA binding by BKLF, but mutation of the sumoylation sites reduces transcriptional repression activity. Most interestingly, when mutations preventing sumoylation are combined with an additional mutation that eliminates contact with the C-terminal binding protein (CtBP) corepressor, BKLF becomes an activator of transcription. These results link SUMO modification to transcriptional repression and demonstrate that both recruitment of CtBP and sumoylation are required for full repression by BKLF. [ABSTRACT FROM AUTHOR]

Background: The purpose of this trial was to test if the Norfolk Diabetes Prevention Study (NDPS) lifestyle intervention, recently shown to reduce the incidence of type 2 diabetes in high-risk groups, also improved glycaemic control in people with newly diagnosed screen-detected type 2 diabetes.Methods: We screened 12,778 participants at high risk of type 2 diabetes using a fasting plasma glucose and glycosylated haemoglobin (HbA1c). People with screen-detected type 2 diabetes were randomised in a parallel, three-arm, controlled trial with up to 46 months of follow-up, with a control arm (CON), a group-based lifestyle intervention of 6 core and up to 15 maintenance sessions (INT), or the same intervention with additional support from volunteers with type 2 diabetes trained to co-deliver the lifestyle intervention (INT-DPM). The pre-specified primary end point was mean HbA1c compared between groups at 12 months.Results: We randomised 432 participants (CON 149; INT 142; INT-DPM 141) with a mean (SD) age of 63.5 (10.0) years, body mass index (BMI) of 32.4 (6.4) kg/m2, and HbA1c of 52.5 (10.2) mmol/mol. The primary outcome of mean HbA1c at 12 months (CON 48.5 (9.1) mmol/mol, INT 46.5 (8.1) mmol/mol, and INT-DPM 45.6 (6.0) mmol/mol) was significantly lower in the INT-DPM arm compared to CON (adjusted difference -2.57 mmol/mol; 95% CI -4.5, -0.6; p = 0.007) but not significantly different between the INT-DPM and INT arms (-0.55 mmol/mol; 95% CI -2.46, 1.35; p = 0.57), or INT vs CON arms (-2.14 mmol/mol; 95% CI -4.33, 0.05; p = 0.07). Subgroup analyses showed the intervention had greater effect in participants < 65 years old (difference in mean HbA1c compared to CON -4.76 mmol/mol; 95% CI -7.75, -1.78 mmol/mol) than in older participants (-0.46 mmol/mol; 95% CI -2.67, 1.75; interaction p = 0.02). This effect was most significant in the INT-DPM arm (-6.01 mmol/mol; 95% CI -9.56, -2.46 age < 65 years old and -0.22 mmol/mol; 95% CI -2.7, 2.25; aged > 65 years old; p = 0.007). The use of oral hypoglycaemic medication was associated with a significantly lower mean HbA1c but only within the INT-DPM arm compared to CON (-7.0 mmol/mol; 95% CI -11.5, -2.5; p = 0.003).Conclusion: The NDPS lifestyle intervention significantly improved glycaemic control after 12 months in people with screen-detected type 2 diabetes when supported by trained peer mentors with type 2 diabetes, particularly those receiving oral hypoglycaemics and those under 65 years old. The effect size was modest, however, and not sustained at 24 months.Trial Registration: ISRCTN34805606 . Retrospectively registered 14.4.16. [ABSTRACT FROM AUTHOR]

Despite currently available therapies, most patients diagnosed with acute myeloid leukemia (AML) die of their disease. Tumor-host interactions are critical for the survival and proliferation of cancer cells; accordingly, we hypothesize that specific targeting of the tumor microenvironment may constitute an alternative or additional strategy to conventional tumor-directed chemotherapy. Because adipocytes have been shown to promote breast and prostate cancer proliferation, and because the bone marrow adipose tissue accounts for up to 70% of bone marrow volume in adult humans, we examined the adipocyte-leukemia cell interactions to determine if they are essential for the growth and survival of AML. Using in vivo and in vitro models of AML, we show that bone marrow adipocytes from the tumor microenvironment support the survival and proliferation of malignant cells from patients with AML. We show that AML blasts alter metabolic processes in adipocytes to induce phosphorylation of hormone-sensitive lipase and consequently activate lipolysis, which then enables the transfer of fatty acids from adipocytes to AML blasts. In addition, we report that fatty acid binding protein-4 (FABP4) messenger RNA is upregulated in adipocytes and AML when in coculture. FABP4 inhibition using FABP4 short hairpin RNA knockdown or a small molecule inhibitor prevents AML proliferation on adipocytes. Moreover, knockdown of FABP4 increases survival in Hoxa9/Meis1-driven AML model. Finally, knockdown of carnitine palmitoyltransferase IA in an AMLpatient-derived xenograft model improves survival. Here, we report the first description ofAML programming bone marrow adipocytes to generate a protumoral microenvironment. [ABSTRACT FROM AUTHOR]

Despite currently available therapies, most patients diagnosed with acute myeloid leukemia (AML) die of their disease. Tumor-host interactions are critical for the survival and proliferation of cancer cells; accordingly, we hypothesize that specific targeting of the tumor microenvironment may constitute an alternative or additional strategy to conventional tumor-directed chemotherapy. Because adipocytes have been shown to promote breast and prostate cancer proliferation, and because the bone marrow adipose tissue accounts for up to 70% of bone marrow volume in adult humans, we examined the adipocyte-leukemia cell interactions to determine if they are essential for the growth and survival of AML. Using in vivo and in vitro models of AML, we show that bone marrow adipocytes from the tumor microenvironment support the survival and proliferation of malignant cells from patients with AML. We show that AML blasts alter metabolic processes in adipocytes to induce phosphorylation of hormone-sensitive lipase and consequently activate lipolysis, which then enables the transfer of fatty acids from adipocytes to AML blasts. In addition, we report that fatty acid binding protein-4 (FABP4) messenger RNA is upregulated in adipocytes and AML when in coculture. FABP4 inhibition using FABP4 short hairpin RNA knockdown or a small molecule inhibitor prevents AML proliferation on adipocytes. Moreover, knockdown of FABP4 increases survival in Hoxa9/Meis1-driven AML model. Finally, knockdown of carnitine palmitoyltransferase IA in an AML patient-derived xenograft model improves survival. Here, we report the first description of AML programming bone marrow adipocytes to generate a protumoral microenvironment. [ABSTRACT FROM AUTHOR]

In addition to their extended lifespans, slow-aging growth hormone receptor/binding protein gene-disrupted (knockout) ( GHR- KO) mice are hypoinsulinemic and highly sensitive to the action of insulin. It has been proposed that this insulin sensitivity is important for their longevity and increased healthspan. We tested whether this insulin sensitivity of the GHR- KO mouse is necessary for its retarded aging by abrogating that sensitivity with a transgenic alteration that improves development and secretory function of pancreatic β-cells by expressing Igf-1 under the rat insulin promoter 1 ( RIP:: IGF-1). The RIP:: IGF-1 transgene increased circulating insulin content in GHR- KO mice, and thusly fully normalized their insulin sensitivity, without affecting the proliferation of any non-β-cell cell types. Multiple (nonsurvivorship) longevity-associated physiological and endocrinological characteristics of these mice (namely beneficial blood glucose regulatory control, altered metabolism, and preservation of memory capabilities) were partially or completely normalized, thus supporting the causal role of insulin sensitivity for the decelerated senescence of GHR- KO mice. We conclude that a delayed onset and/or decreased pace of aging can be hormonally regulated. [ABSTRACT FROM AUTHOR]

Brown adipocytes dissipate energy, whereas white adipocytes are an energy storage site. We explored the plasticity of different white adipose tissue depots in acquiring a brown phenotype by cold exposure. By comparing cold-induced genes in white fat to those enriched in brown compared with white fat, at thermoneutrality we defined a "brite" transcription signature. We identified the genes, pathways, and promoter regulatory motifs associated with "browning," as these represent novel targets for understanding this process. For example, neuregulin 4 was more highly expressed in brown adipose tissue and upregulated in white fat upon cold exposure, and cell studies showed that it is a neurite outgrowth-promoting adipokine, indicative of a role in increasing adipose tissue innervation in response to cold. A cell culture system that allows us to reproduce the differential properties of the discrete adipose depots was developed to study depot-specific differences at an in vitro level. The key transcriptional events underpinning white adipose tissue to brown transition are important, as they represent an attractive proposition to overcome the detrimental effects associated with metabolic disorders, including obesity and type 2 diabetes. [ABSTRACT FROM AUTHOR]

Tinnitus has been associated with increased spontaneous and evoked activity, increased neural synchrony, and reorganization of tonotopic maps of auditory nuclei. However, the neurotransmitter systems mediating these changes are poorly understood. Here, we developed an in vitro assay that allows us to evaluate the roles of excitation and inhibition in determining the neural correlates of tinnitus. To measure the magnitude and spatial spread of evoked circuit activity, we used flavoprotein autofluorescence (FA) imaging, a metabolic indicator of neuronal activity. We measured FA responses after electrical stimulation of glutamatergic axons in slices containing the dorsal cochlear nucleus, an auditory brainstem nucleus hypothesized to be crucial in the triggering and modulation of tinnitus. FA imaging in dorsal cochlear nucleus brain slices from mice with behavioral evidence of tinnitus (tinnitus mice) revealed enhanced evoked FA response at the site of stimulation and enhanced spatial propagation of FA response to surrounding sites. Blockers of GABAergic inhibition enhanced FA response to a greater extent in control mice than in tinnitus mice. Blockers of excitation decreased FA response to a similar extent in tinnitus and control mice. These findings indicate that auditory circuits in mice with behavioral evidence of tinnitus respond to stimuli in a more robust and spatially distributed manner because of a decrease in GABAergic inhibition. [ABSTRACT FROM AUTHOR]

OBJECTIVE-- Optimizing glycemic control in diabetic patients undergoing maintenance hemodialysis requires accurate assessment. We hypothesize that 1) 48-h continuous glucose monitoring (CGM) provides additional, clinically relevant, information to that provided by the A1C measurement and 2) glycemic profiles differ significantly between day on and day off dialysis. RESEARCH DESIGN AND METHODS -- With the use of GlucoDay S, 48-h CGM was performed in 19 type 2 diabetic subjects undergoing hemodialysis to capture consecutive 24-h periods on and off dialysis. Energy intake was calculated using food diaries. A1C was assayed by a high-performance liquid chromatography method. RESULTS-- CGM data were available for 17 subjects (13 male) with a mean (range) age of 61.5 years (42-79 years) and diabetes duration of 18.8 years (4-30 years). The 24-h CGM area under the glucose curve and 24-h mean glucose values were significantly higher during the day off dialysis than on dialysis (5,932.1 ± 2,673.6 vs. 4,694 ± 1,988.0 mmol ⋅ 3 min[sup -1] ⋅ l[sup -l], P = 0.022, and 12.6 ± 5.6 vs. 9.8 ± 3.8 mmol/l, P = 0.013, respectively), independent of energy intake. Asymptomatic hypoglycemia occurred in 4 subjects, 3 within 24 b of dialysis, and the glucose nadir in 14 subjects occurred within 24 h of dialysis. CONCLUSIONS- Glucose values are significantly lower on dialysis days than on nondialysis days despite similar energy intake. The risk of asymptomatic hypoglycemia was highest within 24 h of dialysis. Physicians caring for patients undergoing hemodialysis need to be aware of this phenomenon and consider enhanced glycemic monitoring after a hemodialysis session. CGM provides glycemic information in addition to A1C, which is potentially relevant to clinical management. [ABSTRACT FROM AUTHOR]

Cisplatin, a chemotherapeutic agent of choice for the treatment of solid tumors, produces hearing loss in approximately half a millionnew cancer patients annually in the United States. The hearing loss is due, in part, to increased generation of reactive oxygen species (ROS) in the cochlea, leading to lipid peroxidation and damage or death of outer hair cells in the organ of Corti. The cochlea expresses the transient receptor potential vanilloid 1 (TRPV1), which are normally expressed on small diameter neurons in the peripheral nervous system and mediate thermal sensitivity, but whose role in the cochlea is unclear. In this study, we show that TRPV1 is coregulated along with the NADPHoxidase isoform, NOX3, by cisplatin. Induction of these proteins by cisplatin is dependent on ROS generation, since it is reversed by systemic lipoic acid administration. In organ of Corti hair cell cultures (UB/OC-1 cells), cisplatin activates and induces TRPV1 and NOX3, leading to apoptosis of these cells. Inhibition of TRPV1 by capsazepine or ruthenium red reduced the apoptosis, implicating TRPV1 in this process. Treatment of UB/OC-1 cultures with short interfering RNA (siRNA) against either TRPV1 or NOX3 reduced cisplatin-induced apoptosis, while round window application of TRPV1 siRNA to rats reduced TRPV1 expression, decreased damage to outer hair cells and reduced cisplatin-induced hearing loss. These data provide a link between NOX3 and TRPV1 in cisplatin-induced hearing loss and suggest that targeting these proteins for knockdown by siRNA could serve as a novel approach in treating cisplatin ototoxicity. [ABSTRACT FROM AUTHOR]

Abstract: Neurophysiological studies of salicylate-induced tinnitus have generally been carried out under anesthesia, a condition that abolishes the perception of tinnitus and depresses neural activity. To overcome these limitations, measurement of salicylate induced tinnitus were obtained from rats using schedule induced polydipsia avoidance conditioning (SIPAC) and gap pre-pulse inhibition of acoustic startle (GPIAS). Both behavioral measures indicated that tinnitus was present after treatment with 150 and 250mg/kg of salicylate; measurements with GPIAS indicated that the pitch of the tinnitus was near 16kHz. Chronically implanted microwire electrode arrays were used to monitor the local field potentials and spontaneous discharge rate from multiunit clusters in the auditory cortex of awake rats before and after treatment with 150mg/kg of salicylate. The amplitude of the local field potential elicited with 60dB SPL tone bursts increased significantly 2h after salicylate treatment particularly at 16–20kHz; frequencies associated with the tinnitus pitch. Field potential amplitudes had largely recovered 1–2 days post-salicylate when behavioral results showed that tinnitus was absent. The mean spontaneous spike recorded from the same multiunit cluster pre- and post-salicylate decreased from 22spikes/s before treatment to 14spikes/s 2h post-salicylate and recovered 1 day post-treatment. These preliminary physiology data suggest that salicylate induced tinnitus is associated with sound evoked hyperactivity in auditory cortex and spontaneous hypoactivity. [Copyright &y& Elsevier]

Objectives Associations between calcium-sensing receptor (CaSR) polymorphisms and serum calcium, PTH and bone mineral density (BMD) have been reported by six studies. However, three other studies have failed to detect such associations. We therefore further investigated three CaSR coding region polymorphisms (Ala986Ser, Arg990Gly and Gln1011Glu) for associations with indices of calcium homeostasis and BMD and for alterations in receptor function. Patients and design One hundred and ten adult, Caucasian, female, dizygotic twin pairs were investigated for associations between the three CaSR polymorphisms and serum calcium, albumin, PTH, 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D3[1,25(OH)2D3], urinary calcium excretion and BMD. Each polymorphic CaSR was also transfected into HEK293 cells and functionally evaluated. Results There was a lack of association between each of these three CaSR polymorphisms and serum calcium corrected for albumin, PTH, 25OHD3, 1,25(OH)2D3, urinary calcium excretion or BMD at the hip, forearm and lumbar spine. These findings were supported by a lack of functional differences in the dose–response curves of the CaSR variants, with the EC50 values (mean ± SEM) of the wild-type (Ala986/Arg990/Gln1011), Ser986, Gly990 and Glu1011 CaSR variants being 2·74 ± 0·29 mm, 3·09 ± 0·34 mm ( P > 0·4), 2·99 ± 0·23 mm ( P > 0·4) and 2·96 ± 0·30 mm ( P > 0·5), respectively. Conclusions Our study, which was sufficiently powered to detect effects that would explain up to 5%, but not less than 1%, of the variance has revealed that the three CaSR polymorphisms of the coding region have no major influence on indices of calcium homeostasis in this female population, and that they do not alter receptor function. [ABSTRACT FROM AUTHOR]

Abstract: The fusiform cell and deep layers of the dorsal cochlear nucleus (DCN) show neurotransmitter and functional age-related changes suggestive of a downregulation of inhibitory efficacy onto DCN output neurons. Inhibitory circuits implicated in these changes include vertical and D-multipolar cells. Cartwheel cells comprise a large additional population of DCN inhibitory neurons. Cartwheel cells receive excitatory inputs from granule cell parallel fibers and provide a source of glycinergic inhibitory input onto apical dendrites of DCN fusiform cells. The present study compared the response properties from young and aged units meeting cartwheel-cell criteria in anesthetized rats. Single unit recordings from aged cartwheel cells revealed significantly higher thresholds, increased spontaneous activity and significantly altered rate-level functions characterized by hyperexcitability at higher intensities. Aged cartwheel cells showed a significant reduction in off-set suppression. Collectively, these findings suggest a loss of tonic and perhaps response inhibition onto aged DCN cartwheel neurons. These changes likely reflect a compensatory downregulation of synaptic inhibition in response to a loss of excitatory drive from auditory and non-auditory excitatory inputs via granule cells. The impact of increased excitability of cartwheel cells on DCN output neurons is likely to be complex, influenced by loss of glycinergic release and/or subunit receptor changes which would only partially off-set age-related loss of inhibition onto the somata and basal dendrites of fusiform cells. [Copyright &y& Elsevier]

Kv3.1 channels are voltage-gated potassium channels that enable fast repolarization of the neuronal action potential, and are essential for the high-frequency, high-fidelity firing of neurons in the auditory brainstem and midbrain. Altered activity of these neurons has been implicated in the generation of tinnitus induced by noise exposure. Furthermore, loss of Kv3 channel function has been observed shortly after noise exposure, which may contribute to the maladaptive plasticity leading to the emergence of tinnitus. AUT00063 is a novel, selective modulator of Kv3.1 channels that has been investigated in a number of animal models of noise-induced hearing loss and tinnitus. In Long-Evans rats exposed to a unilateral 116 dB, 16 kHz octave-band noise for one hour, approximately half of the animals demonstrated deficits in auditory gap processing, consistent with the presence of tinnitus. Acute treatment with AUT00063 abolished evidence of tinnitus, without affecting the behavior of control animals or noise-exposed animals without tinnitus. In CBA/Ca mice exposed to 8-16 kHz noise at 105 dB SPL for two hours under anaesthesia, there was a significant increase in spontaneous activity of neurons in the inferior colliculus (IC) when recorded 4 weeks later. AUT00063 decreased IC excitability in noise-exposed animals, returning spontaneous rates to levels similar to those observed in control animals; no such effect was observed following injections of vehicle. These data support the evaluation of AUT00063 for the treatment of people with subjective, noise-related tinnitus. Funding and disclosure: These studies were financially supported by Autifony Therapeutics Limited. CHL, NP and GSA are full time employees of Autifony Therapeutics Limited or Autifony SRL. [ABSTRACT FROM AUTHOR]

We describe the case of a patient who presented with a right-sided glomus jugulare tumor and bilateral glomus vagale tumors. These proved to be nonmalignant paragangliomas on histopathological analysis. Genetic analysis revealed a germline heterozygous missense mutation (Pro81Leu) in the succinate dehydrogenase subunit D (SDHD) gene. We discuss the clinical presentations of the familial paraganglioma syndrome type 1, which is caused by mutations in SDHD, and the implications for the clinical diagnosis and care of such patients. [ABSTRACT FROM AUTHOR]

An abstract of the article "Targeted Disruption of the Basic Krüppel-Like Factor Gene (Klf3) Reveals a Role in Adipogenesis," by Nancy Sues and colleagues are presented.